Approaches to mass customization configurations and empirical validation

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Journal of Operations Management182000605–625

https://www.wendangku.net/doc/df16586466.html, r locate r dsw

Approaches to mass customization:configurations and

empirical validation

Rebecca Duray a,),Peter T.Ward b,Glenn https://www.wendangku.net/doc/df16586466.html,ligan b,William L.Berry b

a College of Business and Administration,Uni?ersity of Colorado at Colorado Springs,Colorado Springs,CO80933-7150,USA

b Department of Management Sciences,Fisher College of Business,The Ohio State Uni?ersity,Columbus,OH43210-1399,USA Abstract

Mass customization is a paradox-breaking manufacturing reality that combines the unique products of craft manufactur-ing with the cost-efficient manufacturing methods of mass production.Although this phenomenon is known to exist in practice,academic research has not adequately investigated this new form of competition.In this research,we develop a configurational model for classifying mass customizers based on customer involvement in design and product modularity. We validate this typology through an empirical analysis and classification of126mass customizers.We also explore manufacturing systems and performance implications of the various mass customization configurations.q2000Elsevier Science B.V.All rights reserved.

Keywords:Mass customization;Process design;Technology;Marketing r operations interface

1.Introduction

Mass customization,once considered a paradox to be resolved in the future,has become an everyday reality for many manufacturers.Stanley Davis coined the term A mass customization B in his1987book, Future Perfect.Davis suggested that existing tech-nology constrained possibilities for mass-customized products,markets,and organizations,although he said that the phenomenon would prevail in the fu-ture.More contemporary researches suggest that the advances in manufacturing,information technology )Corresponding author.Tel.:q1-719-262-3673.

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E-mail address:rduray@https://www.wendangku.net/doc/df16586466.html, R.Duray.and management methods since the publication of Future Perfect in1987have made mass customiza-

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tion a standard business practice Kotha,1995;Pine, .

1993.The confluence of these advances allows producers to customize at low cost and customers to reap the benefits of customized products with rela-tively low prices.

The practice of mass customization does not fit the conventional paradigm of manufacturing man-agement.Historically,companies chose processes that supported the production of either customized crafted products or standardized mass-produced products.This traditional practice means that cus-tomized products usually are made using low volume production processes that cope well with a great variety of products and with design processes that

0272-6963r00r$-see front matter q2000Elsevier Science B.V.All rights reserved.

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can accommodate a high degree of customer in-volvement in specifying the product.In contrast,a mass production process is chosen for making stan-dardized products in a high volume environment where great attention is paid to efficiency and captur-ing scale economies.Further,product variety is rela-tively low in mass production and customer involve-ment is sought through market research only to capture standard product design attributes that have wide appeal.In contrast to the traditional paradigm,?.

Davis1987envisioned a one-of-a-kind product manufactured to customer specification without sac-rificing scale economies.In this way,customers are able to purchase a customized product for the cost of

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a mass-produced item.Similarly,Pine1993defines the goals of mass customization as providing enough variety in products and services so that nearly every-one finds exactly what they want at a reasonable price.

Although these definitions provided by Davis and Pine sketch the essence of mass customization,they do not possess the specificity required to identify companies as mass customizers or how a company can achieve a mass customization capability.Ac-counts of mass customization practices in companies described in the literature label a broad range of production practices mass customization;however, the diversity of the practices and the companies further clouds the meaning of mass customization.In short,extant literature has not established good con-ceptual boundaries for mass customization,nor has that literature presented a means to distinguish among the vast array of mass customization practices in a way that lends clarity.

This paper addresses three important elements missing from the literature.First,we develop a con-ceptual model of mass customization to identify and classify mass customizers.This model is based on the key dimensions of mass customization and vali-dated through literature,field studies,and survey testing.Second,we develop a classification scheme to group mass customizing companies according to the way they achieve mass customization.Third,we explore different approaches to mass customization implied by the typology by comparing the manufac-turing approach of each type.Our approach yields mass customization configurations that are empiri-cally validated.

We establish the external validity of the model through empirical investigation of companies in six different industries.By using a number of industries in our sample,we address the issue of whether mass customization is a robust concept applicable across a range of industries,or whether it can be applied only to a limited number of special cases.On the other hand,by limiting the study to six industries,we are able to show that mass customization is a competi-tive choice open to a number of competitors in the same industries.In addition,we are able to control and test for industry effects.

2.Research proposition

Because mass customization is a relatively new idea;scholarly literature related to the topic is scant. In this research,we seek to uncover the important dimensions of mass customization from an opera-tions perspective.We argue that the essence of mass customization lies in resolving the seeming paradox of mass producing custom products by finding effi-ciencies in two key dimensions.First,mass cus-tomizers must find a means for including each cus-tomer’s specifications in the product design.Second, mass customizers must utilize modular design to achieve manufacturing efficiencies that approximate those of standard mass produced products.Choices made by mass customizers on how they approach these two dimensions suggest a useful typology of mass customization:

Proposition1.Mass customizers can be identified and classified based on two characteristics:the point in the production cycle of customer in?ol?ement in specifying the product and the type of product modu-larity employed.Each mass customization configura-tion exhibits a distinct approach to the manufacture of mass-customized products.

More specifically,we will suggest a classification with four fundamental,mutually exclusive types of mass customizers.We argue that this typology will also serve to identify manufacturers that do not mass customize.

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The underlying choices with respect to customer involvement in design and modularity type imply different approaches to manufacturing processes, policies,and technologies,thereby making the classi-fications useful to manufacturers.In other words, knowing the point at which a mass customizer in-volves the customer in product design and the ap-proach to modularity taken by the mass customizer suggests the configuration of processes and technolo-gies that will be used in designing and making the mass-customized product.We concede that other characteristics such as flexibility,agility,or service approach also play important roles in mass cus-tomization viewed from an operations perspective. We argue,however,that customer involvement and modularity are the key elements in defining mass customization approach.This paper develops and tests this argument in detail in the following manner.

To explore this proposition,we first develop the dimensions of mass customization and discuss the implications of the mass customization configura-tions from a theoretical perspective.Then,the model is operationalized through an empirical evaluation of 194manufacturing plants.These data are used to establish the mass customization dimensions in prac-tice,classify actual plants,and explore these mass customization configurations in the context of the manufacturing systems variables employed.

3.Mass customization dimensions

The boundaries of mass customization can be more clearly established by delineating two issues:?.?.

1the basic nature of customization and2the means for achieving customization at or near mass production costs.The first issue,the nature of cus-

?. tomization,has been addressed by Mintzberg1988.

A customized product is designed specifically to meet the needs of a particular customer.Variety provides choice for customers,but not the ability to specify the product.A great deal of variety in the marketplace may satisfy most customers and,hence, substitute for customization;but customization and variety are distinct.For example,having hundreds of varieties of breakfast foods on the shelf of the super-market is different from being able to specify one’s exact breakfast food formulation from the cereal supplier.It is important to realize that the availability of hundreds of varieties probably limits the market appeal of customized products for most customers. However,variety is not customization.As Womack ?.

1993remarks,this distinction between customized products and product variety is overlooked in the examples of companies pursuing mass customization ?.

by Pine1993.This distinction is important because it implies that customers must be involved in speci-fying the product.

The second issue that we delineate—the method of achieving customization at or near mass produc-tion costs—addresses the A mass B in mass cus-tomization.How can unique products be developed and manufactured in a mass production fashion? How can high volume,low cost customization be

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implemented?Pine1993argues that modularity is a key to achieving mass customization.Modularity provides a means for the repetitive production of components.Modularity allows part of the product to be made in volume as standard modules with product distinctiveness achieved through combination or modification of the modules.Therefore,modules that will be used in the custom product can be manufac-tured with mass production techniques.The fact that parts or modules are standardized allows for mass-customized products to achieve the low cost and consistent quality associated with repetitive manufac-turing.Thus,modularity can be viewed as the critical aspect for gaining scale or A mass B in mass cus-tomization.We further develop the issues of cus-tomization and modularity to provide a basis for a more comprehensive definition of mass customiza-tion.

3.1.Customization issues

A customized product must be designed to cus-tomer specifications.From the literature,it is appar-ent that identifying the point of initial customer involvement is critical to determining the degree of

?. customization.Mintzberg1988and Lampel and ?.

Mintzberg1996developed the idea that the level of customer involvement in the production cycle can play a critical role in determining the degree of

?. customization.McCutcheon et al.1994argued that

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the production stage where a product is differentiated is a key variable in process choice decisions.By extension,the point of customer involvement in specifying the product also may be related to choices about the customization process.We argue that the point of customer involvement in the production cycle is a key indicator of the degree or type of customization provided.For purposes of defining mass customization,we take a narrow view of the production cycle.Specifically,we include four points in the production cycle:design,fabrication,assem-bly,and use.If customers are involved in the early design stages of the production cycle,a product could be highly customized.If customer preferences are included only at the final assembly stages,the degree of customization will be not as great.In this manner,point of customer involvement provides a practical indicator of the relative degree of product customization.

Thus,we argue that products with early customer involvement are relatively more customized than those with later involvement.The typology of ?.

Mintzberg1988supports this reasoning.Mintzberg views customization as taking one of three forms: pure,tailored,or standardized.Each form differs in the portion of the production cycle involved and the degree of uniqueness of the product.A pure cus-tomization strategy furnishes products designed and produced from scratch for each individual customer. Pure customization includes the customers in the entire cycle,from design through fabrication,assem-bly and delivery and it provides a highly customized product.A tailored customization strategy requires a basic design that is altered to meet the specific needs of a particular customer.In this case,the customer enters the production cycle at the point of fabrication where standard products are modified.In a standard-ized customization strategy,a final product is assem-bled from a predetermined set of standard compo-nents.Here,the customer penetrates the assembly and delivery processes through the selection of the desired features from a list of standard options.The

?. categorization of Mintzberg1988shows that the type of customization chosen by the producer im-plies different levels of customer involvement in product design and different points at which that involvement begins.These different customization strategies also imply degrees of customization,with pure customization providing the highest degree of customization with all of the products designed specifically for the customer,and standard cus-tomization the lowest degree with only an arrange-ment of components determining the customized configuration.

3.2.Modularity issues

Mass customization requires that unique products be provided in a cost-effective manner by achieving volume-related economies.A number of observers suggest that modularity is the key to achieving low

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cost customization.Pine1993stated that true mass customization requires modularity in production,al-though he was not specific about where or how

?. modularity should be used.Baldwin and Clark1994 discussed modularity in production as a means to partition production to allow economies of scale and ?.

scope Goldhar and Jelinek,1983across the product

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lines.McCutcheon et al.1994suggested that mod-ular product design is the best way to provide variety and speed,thereby alleviating the customization re-sponsiveness squeeze,which occurs when customers demand greater variety,and reduced delivery times simultaneously.A modular approach can reduce the variety of components while offering a greater range of end products.Flexible manufacturing systems ?.

FMS provide for lower cost customization through the use of some form of modularity in their design. In the design of products for FMS manufacture, program modules for different product characteristics are used to achieve fast set-up manufacture.These program modules are used to repeat manufacturing sequences across products and provide for modular-ity in the design of new products.Therefore,FMS production contains modularity.

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Similarly,Ulrich1992argued that modularity can help increase product variety,but he also ad-dressed the use of modularity to shorten delivery lead times,and provide economies of scope.Pine et ?.

al.1995asserted that to be successful,mass cus-tomizers must employ a production r delivery strat-egy that incorporates modularity into components and processes.In essence,the literature suggests that modularity can facilitate increasing the number of product features available while also decreasing costs.

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Therefore,it follows that the successful implementa-tion of mass customization requires effective use of modular product designs.

Modularity is multifaceted in concept and is gen-erally described either in relative terms or as a

?. typology.For example,Ulrich and Eppinger1995viewed modularity as a relative property with prod-ucts characterized as more or less modular in design. To better distinguish types of mass customizers,a range of modularity types should be considered. Modularity can take a number of forms.The various types of modularity found in production

environ-

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Fig.1.Modularity types Ulrich and Tung,1991.

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ments were discussed in Pine1993,although he does not explicitly link modularity types with mass customization.More recently,Ulrich and Tung ?.

1991developed a similar typology of modularity. Fig.1depicts these types of modularity.

Modularity can represent many forms of flexible manufacturing.For example,Levi Straus’custom-fit jeans are made possible through their flexible manu-facturing process,which cuts each unique pattern prior to stitching and sewing.In the Ulrich and Tung typology,the Levi’s example can be described as a A cut-to-fit B modularity.The unique patterns are built upon one traditional style of five-pocket jeans that is altered or A cut-to-fit B the specific dimensions of the customer.These A made-for-you B jeans are available

?. for alteration only within a limited size range0–18. The concept of modularity is a basic building block in the manufacturing situations traditionally consid-ered to be flexible.

To make the concept of modularity operational, Ulrich and Tung’s typology is adopted and inte-grated into the framework of the production cycle,as seen in https://www.wendangku.net/doc/df16586466.html,ing the design r production process as a reference point,the different types of modularity can be assigned to the phases of the product cycle.For example,during the design and fabrication,mod-ules can be altered or components can be fabricated to provide for the unique requirements of the cus-tomer.Cut-to-fit and component sharing modularity require that components are newly designed or changed;therefore,these types of modularity must take place during the design and fabrication stages. With cut-to-fit modularity,components are altered to the physical dimensions specified by the customer. This alteration requires the fabrication of a compo-nent that is standard except in a specific dimension, e.g.,length,that is specified by the customer.This customization necessarily takes place during the de-sign r fabrication stages.In general,component shar-ing also takes place in the design and fabrication stages.Although a standard base unit is incorporated into the product,additional components are fabri-cated to provide an end-product that meets customer specification.Modularity incorporated in the stan-dard base simplifies fabrication and reduces the total cost of the customized product.

During the assembly and use stages,modules are arranged or combined according to customer specifi-cation,but components cannot be manufactured nor can modules be https://www.wendangku.net/doc/df16586466.html,ponent swapping,

sec-Fig.2.Customer involvement and modularity in the production cycle.

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tional,mix,and bus modularity use standard mod-ules without alteration;therefore,these types of modules can be combined during the assembly and use stage of the production cycle.In each case, standard modules are combined to form an end-prod-uct that is specified by the customer.In their pure form,component swapping,sectional,mix,and bus modularity all provide customization by allowing customers to specify a choice among a number of standard modules without the option of altering any of the modules.In particular,sectional modularity can also be used in the post-production phases where the customer combines components across manufac-?.

turers e.g.,stereo components.Sectional modular-ity may require the adoption of uniform industry ?. standards Garud and Kumaraswamy,1993.

When customer involvement in specifying the product and modularity types are combined,mass customization can be fully realized in practice.Cus-tomer involvement provides the customization while the modularity restricts the range of choice to de-crease the possible variety of components,thus al-lowing for repetitive manufacturer.When modularity is employed in mass-customized products,product distinctiveness is a result of either the combination of standard modules into a finite number of permuta-tions or the alteration of prescribed modules into a limited range of products.In contrast,purely cus-tomized products are infinite in permutations result-ing from craft manufacture.Modularity bounds the degree of customization of the product and distin-guishes mass customization from pure customized products.The fact that these parts or modules are standardized allows for mass-customized products to achieve the low cost and consistent quality associ-ated with repetitive manufacturing.

4.Mass customization configurations

In Section3,we argue that the model of mass customization that emerges from the literature uses two critical identifiers:customer involvement in the production cycle and modularity type.Bringing these concepts together,mass customization can be de-fined as building products to customer specifications using modular components to achieve economies of scale.Distinctions can be made among mass cus-tomizers based on the point at which the customer becomes involved in the design process and the type of modularity employed by the producer.These two attributes are interrelated and when taken together suggest mass customization archetypes.Fig.3shows the dimensions juxtaposed,with point of customer involvement in design and type of modularity form-ing the archetypes.

4.1.Classification matrix

As shown in Fig.3,mass customizers can be identified and classified based on customer involve-ment and modularity type.Mintzberg’s definitions of customization provide a good beginning for describ-ing the degree of customer involvement and can be seen down the left-hand column.When customers are involved at the design stage,products can be altered to fit customers’expectations with infinite variety.In the fabrication stage,customer involve-ment means specifying relatively incremental changes to a standard design.In the assembly stage,customer requirements must be met from a finite set of com-ponents.These two stages represent a time in the production cycle when customer preferences require physically altering existing components or cons-tructing unique components.Building further on Mintzberg’s ideas,customer involvement in the post-production or use stage should also be consid-ered.A product that can be adjusted or manipulated by the consumer to provide customization at the point of delivery can also be considered mass-custo-

?.?. mized.Both Davis1987and Pine1993discuss this type of post-production customization which that we refer to as A point of sale customization B.

Modularity provides the basis for repetitiveness in production or the A mass B in mass customization.

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Baldwin and Clark1994use phases in a product’s development to circumscribe the type of modularity employed.They argue that the type of modularity differs at different points in the production cycle.

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The typology of Ulrich and Tung1991identifies types of modularity that can be employed that,by definition,fit the stages of the production processes of design and manufacturing.The model,depicted in Fig.3,overlays Baldwin and Clark’s production

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612Fig.3.Matrix grouping of mass customization configurations.

phases with Ulrich and Tung’s modularity types.Modularity is addressed across the top row of the model.When modules are designed to provide the ability to modify components,modularity will be utilized in the design and fabrication stages of the production cycle.In the later stages of the production cycle,assembly and use,modules are added or inter-changed,but not altered.4.2.Archetypes

The juxtaposition of customer involvement and modularity create four groups or mass customization types.Group 1includes both the customer involve-ment and modularity occurring during the design and fabrication stages.Since in this instance both the customer involvement and modularity require fabri-cating a customized component,we name this group the Fabricators .Fabricators involve the customers early in the process when unique designs can be realized or major revisions can be made in the products.Fabricators closely resemble a pure cus-tomization strategy,but employs modularity to gain commonality of components.An example of a Fab -ricators is Bally Engineered Structures,a manufac-turer of walk-in coolers,refrigerated rooms,and ?.clean rooms described by Pine et al.1993.Product modules are cut-to-fit specific dimensions of the customer,providing unique rooms manufactured from modular components.Modular components are altered in fabrication to A fit B the specific building.In addition,unique components may be designed for

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specific application.Customers are involved in the design and fabrication stage of the production cycle, and component sharing and cut-to-fit modularity are used to provide the mass-customized product.

Group2incorporates customer involvement in product design during the design and fabrication stages but uses modularity during the assembly and delivery stages.Because customer involvement pre-cedes the use of modularity,we refer to this group as In?ol?ers.With In?ol?ers,customers are involved early in the process although no new modules are fabricated for this customer.Customization is achieved by combining standard models to meet the specification of the customer.Perhaps,the early involvement of the customer imbues the customer with a greater sense of customization or ownership of the product design,although no customized com-ponents are fabricated.Because they do not fabricate customized components to customer specification, In?ol?ers capture greater economies of scale than Fabricators while maintaining a high level of cus-tomer involvement.An example of this type of mass customizer is Andersen Windows.Andersen uses a design tool that helps customers develop the specific design of their windows.However,products are produced from50,000possible window components ?.

Pine et al.,https://www.wendangku.net/doc/df16586466.html,ponents are not designed or fabricated for the specific application.However,cus-tomers specifications are A designed B and then,the components are selected by the manufacturer to fit this design.The sheer number of components pro-hibits the customer from simply choosing from a prescribed list,as with component swapping modu-larity.The customer is involved in the specification during the design and fabrication stages,but the product is assembled from modular components in the assembly and use stages of the production cycle.

Group3involves the customer during assembly and delivery but incorporates modularity in the de-sign and fabrication stages.Group3,which we call Modularizers,develops a modular approach in the design and fabrication stages,although customers do not specify their unique requirements until the as-sembly and use stage.Modularizers use modula-rity earlier in the manufacturing process than when customization occurs.This modularity may be considered component commonality.In this type, Modularizers may not gain maximum customization advantages from modularity.For example,a mass customizing upholstered furniture manufacturer uses modularity in the design of a sofa frame which is

?. used in many product lines component sharing. This modularity provides for component commonal-ity,but is not used for customization.In the assem-bly stage,a customer chooses a fabric or wood finish

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from a prescribed list component swapping,provid-ing some degree of customization.Modularizers in-corporate both customizable modularity in the later stages of the production cycle and non-customizable modularity in the design and fabrication stages of the production cycle.

Group4brings both customer involvement and modularity to bear in the assembly and use stages. We call this group Assemblers.Assemblers provide mass customization by using modular components to present a wide range of choices to the customer. Assemble-to-order manufactures can be considered mass customizers if customers specify products from a pre-determined set of features.Assemblers more closely resemble the operations of mass production than the other configurations of mass customers. Assemblers differ from mass producers in that the products have been designed so that the customer can be involved in specifying the product.Because the range of choices made available by Assemblers is large relative to mass producers,customers per-ceive the product to be customized.Motorola pagers, a recognized leader in mass customization,can be considered a A mass standard B customizer.Pagers can be designed to a customer’s specification from a wide range of options that are added at the produc-?.

tion phase Pine,1993;Donlon,1993.

In short,mass customizers can be typed on the basis of two key dimensions:modularity and cus-tomer involvement.These same dimensions can be used to identify companies that do not possess mass customization capabilities.Manufacturers that do not involve the customer in the design process or do not employ modularity should not be considered mass customizers.Without some degree of customer in-volvement in the design process,a product cannot be considered as https://www.wendangku.net/doc/df16586466.html,panies that do in-volve the customer in the design process,but do not exhibit modularity in manufacturing,are also ex-cluded.These manufacturers should be considered the traditional customizers,a producer of one–off

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goods without the economies of repetitive manufac-turing.

It is interesting to note that applying this typology allows us to conclude that some widely cited exam-ples of mass customization do not fit the bill.For

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example,Davis1987used Cabbage Patch dolls as an example of gaining a competitive edge through mass customization.While it is true that each doll is a unique end-item which customers select at a retail outlet,the customer does not participate in the design of the doll.To be mass-customized,the producer would have to offer customers a means of having a doll made to their specifications,such as eye or hair

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color.Similarly,Pine1993used Swatch watches as an example of mass customization.Swatch offers customers an extraordinarily wide selection of prod-ucts.Although this provides great variety,customers do not have the ability to specify the design in any way;therefore,this example misses the mark.These examples illustrate that the two-dimensional opera-tional definition of mass customization lends clarity to the more casual definitions found in the literature.

5.Empirical validation

The conceptual typology presented above has been validated using both secondary and primary data and both case studies and surveys.In using multiple

?. methods,we follow the advice of Harrigan1983 who argued for using multiple research methodolo-?.

gies or granularities for testing business strategy models.Case studies provide the ability to capture nuances of a company’s strategy,while surveys of larger samples allow more confidence in general conclusions.

The typology validation process itself provides for

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three levels of granularity Harrigan,1983.Initially, the model was validated using case examples from practitioner journals which discuss mass customiza-tion examples.Fifteen companies were identified that appear,based on the information provided in the literature,to exhibit mass customization character-istics.The next level of validation included inter-views with managers from companies randomly se-lected from an APICS directory to determine the extent of product customization.Based on the infor-mation obtained in the interview,more than half of the companies selected at random could be consid-ered mass customizers.These interviews suggested that mass customization might be practiced in some form by a fairly large portion of companies drawn at random.A more intensive study of mass customiza-tion,including plant visits and phone interviews,was then conducted in the furniture industry.The furni-ture industry was selected for plant visits since this industry has traditionally provided customization of end-products.This more in-depth study of furniture manufacturers was used to better illustrate mass cus-tomization characteristics prior to the survey,as well as validate the survey instrument.The third level of validation included a survey of639companies in industries anticipated to include mass customizers based on evidence from the literature.This three-level validation process provides both coarse-and fine-grained looks at mass customization configurations to substantiate the conceptual model.In this paper, we concentrate on the model validation through the survey and use the data collected from the194 respondents to validate the model.

5.1.Sur?ey methods

The sample was drawn from the Society of Manu-

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facturing Engineers SME membership data.Re-

?spondents were selected based on title Vice Presi-dent of Manufacturing,Manufacturing Manager,

.

Plant Manager to assure that respondents repre-sented a high level of responsibility.Executives in the sample were selected randomly but their compa-

?. nies were limited by size more than50employees,?

industry furniture and fixtures,fabricated metal products,machinery except electrical,electric and electronic equipment,transportation equipment,and

.?instruments and related products and geography In-diana,Massachusetts,Michigan,North Carolina,

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Ohio,and Pennsylvania.Size and geographic limita-tions were imposed in the interest of homogeneity and efficiency.Because we seek to understand mass customization practice rather describe its prolifera-tion,industries were selected on the basis of external evidence suggesting that mass customization was fairly common in these https://www.wendangku.net/doc/df16586466.html,ing the methods

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suggested by Dillman1978and Salant and Dillman ?.

1994,the questionnaire was sent to639plants with

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194responding30.4%.

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To determine if the respondents differed signifi-cantly from those that did not respond,the job classification of the respondents and total sample were compared.The portion of respondents in each category was compared to the expected number of respondents based on the percentage of each cate-gory represented in the total sample.A Chi-squared test of the expected and actual number of respondent was not significant at the level of a s0.05.This finding supports the assertion that there was no systematic difference between those companies re-sponding to the survey and those that did not.

In addition,a similar test was performed using industry classification.The portion of respondents in each category was compared to the expected number of respondents based on the percentage of each category represented in the total sample.A Chi-squared test of the expected and actual number of respondent was significant at the level of a s0.05, indicating that respondents may differ from non-re-spondents in industry representation.This result is not surprising as the questionnaire was directed at plants producing customized products and standard product manufacturers may have been reluctant to respond.The level of customization of products will most likely differ between the industries represented. Since customizers are more likely to respond,this may explain the respondent bias based on industry codes.

Multiple respondents from the same plant are compared to assess the degree of agreement and thereby appraise the reliability of responses from the

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primary informants.James et al.1984developed a method to assess the degree of agreement among raters.Data for two respondents were collected for 47plants in the present study.Threshold values have been established to determine A good B reliability, where values closer to1.0represent better agree-ment.All values reported for the scales used exceed 0.70and,therefore,are judged to have A good B agreement.

To focus respondents on the customized portion of their product lines that may be produced at a plant,the following definition of customization was included in the survey:

Customized products are those products that are designed,altered,or changed to fit the specifica-tions of an end-user.Please answer the following

questions regarding only your A customized B https://www.wendangku.net/doc/df16586466.html,ponent or intermediate products are only considered to be customized if the user of the finished product dictates or influences the specifi-cations of the component.

5.2.Instrument de?elopment

To the extent possible,established scales were used to enhance validity,reliability and generaliz-ability of measures.Established scales were used extensively for the contextual variables and will be described in Section5.2.2.When proven established scales were not available,survey questions were developed based on existing literature.The classifi-cation variables,customer involvement and modular-ity were developed from literature and are discussed in detail in Section5.2.1.

5.2.1.Classification?ariables

Because of the paucity of empirical research pub-lished on mass customization,two key scales were constructed:customer involvement in the design pro-cess and product modularity.Exploratory factor anal-ysis using Principle Components and a Varimax rotation was used for the two scales representing customer involvement and modularity,respectively, as the initial determinant of factor composition fol-lowing the criteria recommended by Hair et al.?.

1992.These authors suggested that for a simple structure factor solution,only one loading on any factor for each variable should be significant,and that the lowest factor loading to be considered signif-icant would,in most instances,be0.30.These crite-ria were upheld for both the customer involvement and modularity scales.All items had significant fac-tor loadings on at least one factor as described by ?.

Hair et al.1992.

Following the logic recommended by Carmines ?.

and Zeller1979,the number of factors was deter-mined using an external validation technique.Gerb-

?.?. ing and Anderson1988and Anderson et al.1987 suggested a similar technique using the correlation of factors with external variables to test for unidimen-sionality of factors.External validation techniques and inter-item analysis were used to determine the number and composition of the factors and to vali-date the unidimensionality of these factors.These

?. methods are supported by Flynn et al.1990,Ander-

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R.Duray et al.r Journal of Operations Management182000605–625 616

?.

son and Gerbing1982,and Carmines and Zeller ?.

1979.Further factor simplification and reliability assessments were made using Cronbach’s reliability coefficients.The resulting factors were developed using the factor analysis to produce individual stan-dardized factor scores.

5.2.1.1.Customer in?ol?ement.To determine the point of customization in the production cycle,this survey addressed the stages where an end-user cus-tomer participates in specifying the https://www.wendangku.net/doc/df16586466.html,ing

?.

the definition of Mintzberg1988as a guideline, items were included that address the various ways products can be specified from customers.These questions were designed to measure the point of customer involvement in the design process as one of the following:design,fabrication,assembly,or use.Respondents were asked to indicate the level of agreement,from strongly disagree to strongly agree, with each customer-involvement-related statement using a seven-point Likert scale.

The initial exploratory factor solution was simpli-fied using inter-item analysis and validated following the logic of construct validation,as described above. One item was dropped from each of the scales.In factor one,A customers can assemble a product from components B was omitted to increase the Cronbach’s alpha coefficient from0.7422to0.7657.In factor two,A customer specifications are used to alter stan-dard components for each order B was dropped to improve the Cronbach’s alpha coefficient from 0.6255to0.6404.Both these factors’Cronbach’s coefficient alpha exceed the0.60threshold often

?.

cited for exploratory work Nunnally,1978to assess inter-item reliability.The resulting two factors repre-sent customer involvement in the design process and support the constructs proposed in the original con-ceptual model.These two factors are intuitively ap-pealing as they place customer involvement into one of two stages of the production cycle:design and fabrication or assembly and use.The specific items that support each factor are shown below.

5.2.1.2.Customer in?ol?ement in the design and

()

fabrication stages CI DESFAB.

–

?Customer’s requests are uniquely designed into the finished product;?Each customer order requires a unique design;

?Customers can specify new product features;

?Each customer order requires the fabrication of unique components prior to assembly;and

?Customers can specify size of products.

5.2.1.3.Customer in?ol?ement assembly and use ()

CI ASMUSE.

–

?Each customer order is assembled from compo-nents in stock;

?Customers can select features from listings;

?Customer orders are filled from stock;and

?Customers can assemble a product from compo-nents.

?.

The first factor CI DESFAB represents cus-

–

tomer involvement in the design and fabrication stages.Customers can change the actual design of the product or introduce new features rather than selecting features from a listing as specified in the factor,CI ASMUSE.This involvement requires the –

design or fabrication of a unique component for such customers.

?.

In the second factor CI ASMUSE,all items

–

relate to the involvement of the customer through the selection of standard components or products from a prescribed listing of features.This involvement does not allow for new designs or features to be produced; therefore,the customer is not involved in design and fabrication,but instead in the assembly or use stage of the production cycle.

In combination,these two factors,CI DESFAB

–

and CI ASMUSE,accurately depict the role of the –

customer in the design process as seen in Fig.3. CI DESFAB represents the involvement of the cus-–

tomer at the beginning stages of the production cycle,when product are designed and components are fabricated.CI ASMUSE represents involvement

–

of the customer in the assembly and use stages of the production cycle.Positive values for these scales show that the respondent agrees that a particular mode of customer involvement is used in their cus-tomized product line.Negative values show that the respondents disagree that customers are involved at a particular point in the production cycle.

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5.2.1.4.Modularity.The type of modularity employed is suggested to be a critical issue in under-standing a manufacturer’s approach to mass cus-tomization.Items addressing the modularity of cus-tomized product lines are based on the definition of

?.?. modularity types of Ulrich and Tung1991Fig.2. The initial exploratory factor solution was simplified using inter-item analysis and validated following the logic of construct validation of Carmines and Zeller ?.

1979.The resulting two-factor solution is presented below.

?.

The first factor MOD FAB includes four items

–

that reflect modularity issues involving design or changes to the components for a specific customer. MOD FAB can be considered a measure of modu-–

larity in the design or fabrication of a product.The

?.

second factor MOD STD contains five items that

–

address modularity in the form of options to standard products or interchangeability of components.This type of modularity most likely will be utilized in the assembly stages of a manufacturing process.These two factors represent two distinct approaches to modularity.The components of these factors are listed below.

(

5.2.1.5.Modularity through fabrication MOD–

)

FAB.

?Components are designed to end-user specifica-tions;

?Components are sized for each application;

?Components are altered to end-user specifica-tions;and

?Component dimensions are changed for each end-user.

(

5.2.1.

6.Modularity through standardization MOD–

)

STD.

?Products have interchangeable features and op-tions;

?Options can be added to a standard product;

?Components are shared across products;

?New product features are designed around a stan-dard base unit;and

?Products are designed around common core tech-nology.

Reliability assessments were made using Cron-bach’s reliability coefficients.MOD FAB achieved

–

a Cronbach’s alpha of0.7887and MOD STD

–yielded a coefficient of0.6901.These alpha values both exceed the suggestion of0.60for exploratory

?.

research by Nunnally1978.

When taken together,these two factors provide a measure of the types of modularity in use.MOD–FAB,when positive,indicates that the respondent agrees that some components are fabricated or sized to provide customization in their products.MOD–STD,when positive,indicates that the respondent agrees that features and options are added to stan-dardized components or base technologies to achieve customization of end-products.

5.2.2.Contextual?ariables

The typology is explored using manufacturing decision variables that reflect the paradoxical nature of mass customization.Mass customizers can choose to develop manufacturing systems that are based on the traditional manufacturing practices of A custom B craft or standard A mass B produced products.Three categories of structure and infrastructure manufactur-

?

ing decision variables Hayes and Wheelwright, .

1984were used to represent the manufacturing sys-tem variables that are implicit in the tactical opera-tion’s concepts of A mass B and A custom B.To explore the nature of A mass B in a manufacturing system,the structural variables of process choice and technology were used.Inherent in the process choice decision is an implication of product volumes as seen in the

?

Product–Process matrix variables Hayes and

.

Wheelwright,1984.If high volumes are anticipated, as in standard product production,line processes are selected over job shop processes that are reserved for craft production.Therefore,the selection of line processes may imply that mass customizers are utilizing a large volume of modules or standard components.Process choice was represented by the respondent assessing the usage rates of the traditional process forms:job shop,batch,line,continuous.To capture the usage of purchased components, A purchased from suppliers B was added.Respondents were asked to identify,on a seven-point Likert scale, the appropriate level of usage expressed as a percent-age of the products from A No Products—0%B,

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through A Some Products—50%B,to A All Products —100%B.

To update the traditional process choice alterna-tive,technology usage also was selected as an indica-tor of A mass B manufacturing techniques.Newer manufacturing technologies may provide similar in-dications of higher volume production of standard parts or modules.Technology variables were devel-oped based on a set of items in the Boston Univer-

?

sity Manufacturing Futures Project Miller and Voll-

.

mann,1985;Ward et al.,1988.These items have been used effectively and have been deemed reliable ?. De Meyer and Ferdows,1985;Boyer et al.,1996. These scales develop three technology variables:de-sign,manufacturing and administrative.Administra-tive technologies are used to represent process con-trol methods.Variables were included to represent design and manufacturing technologies to better ex-amine the nature of the manufacturing approach of each type.Design technologies include:Computer-

?.

Aided Design CAD,Computer-Aided Engineering ?.

CAE,and Computer-Aided Process Planning ?.

CAPP.The manufacturing technologies include:

?.

Computer Numerical Control CNC,Computer-

?.

Aided Manufacturing CAM,Robotics,Real-time

?. process control system,Group Technology GT, FMS,and bar coding r automatic identification.The respondent was asked to A Please indicate the extent to which the following are used for your‘custo-mized’products B.The seven-point Likert scale was anchored at1with A not used—0%B,at4with A used for some orders—50%B,and at7with A used for all orders—100%B.

Customization of products can also be assessed by the usage of variables representing production plan-ning and material control methods as described by

?.

Hayes and Wheelwright1984.Administrative tech-nologies can be used to assess these methods.In

?.

addition,Vickery et al.1999used a firm’s made-?.

to-order MTO capability to capture the extent to which a company customizes.The use of production planning methods to facilitate MTO manufactu-ring was used as a tactical representation of cus-tomization in manufacturing systems.Variables were included to explore administrative technology and production control methods.Administrative tech-nologies were developed from the scales described ?

above De Meyer and Ferdows,1985;Boyer et al.,

.

1996.Administrative technologies include:Elec-

?.

tronic Data Interchange EDI,Material Requirement ?.?. Planning MRP,Decision Support Systems DSS, and Knowledge-Based Systems.These technologies can be used to facilitate the production planning and material control functions.

Production planning techniques also were mea-sured by assessing the usage of different methods:

?.

MTO,made-to-stock MTS,assemble-to-order ?.

ATO and JIT.The respondent was asked to A Please indicate the degree to which the following produc-tion planning techniques are used for my‘custo-mized’product line B.The seven-point Likert scale was anchored with A strongly disagree B and A strongly agree B.

5.3.Financial performance

Business performance is a crucial indicator for all

?. strategic configurational works Ketchen et al.,1993. To obtain a relative measure of performance while preserving privacy,this study used perception of performance in relation to competitors.Return on

?. investment,return on sales profit margin,and mar-ket share were used to measure performance relative to competitors.In addition,growth in these mea-sures,as well as sales growth,was used to capture trend in performance.These measures have been

?. used most recently as a group in Boyer et al.1997

?.

and Vickery et al.1994.This performance factor achieved a Cronbach’s alpha of0.914,which ex-ceeds suggestions for exploratory research by Nun-?.

nally1978.

6.Operationalized model

Customer involvement in the production process determines the degree of uniqueness of the product, and is represented by two variables,CI DESFAB

–

and CI ASMUSE.CI DESFAB represents involve-––

ment in the design and fabrication stage while CI–ASMUSE represents involvement during the assem-bly or use phases.Modularity follows a similar pattern.Modularity in the design and fabrication of a product is represented as MOD FAB,and MOD

––STD represents the use of standardized components in the assembly or use phases of a production.

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6.1.Classification criteria

To classify any company,the specific combina-tion of customer involvement and modularity vari-ables must be examined.In practice,it is reasonable to assume that once a customer is involved in the process,or modularity is employed,that involvement or modularity would carry throughout the production cycle.For example,if a customer’s initial point of involvement is in the design stage of the production cycle,the customer’s preference would be incorpo-rated throughout the remaining stages of fabrication, assembly,and use.With regard to modularity,a similar situation exists.If a product were manufac-tured from modular components in the design pro-cess,these modular components would be included in the product throughout the production cycle.Since only one measure is required of each company for each construct,the earliest point of involvement in the production process,either customer or modular-ity,will be used to represent the respective variable for that company.For each case,a set of two values, one that corresponds to the customer involvement axis and one that represents the modularity axis,is needed.

To operationalize this concept,the factor scores corresponding to the earliest point of involvement, design and fabrication,of the product will be consid-ered first.If a respondent company scores positively in the design and fabrication variable,this variable will be used to represent the construct on the axis.If a company’s response yields a negative score,the design and fabrication variable is excluded and the assembly and use variable is examined.A positive value on assembly and use is used to represent the construct,while negative values are excluded.If negative values occur for both the design and fabri-cation variable and the assembly and use variable,no value is assigned.Table1shows the mass customiza-tion groups and the corresponding variable values.

Once each company has been assigned one value for each of the variables,customer involvement and modularity,the classification process is simplified. Each respondent is assigned to a specific cell of the matrix based on the values used to create the vari-able.If a company has customer involvement and modularity variables assigned from the design and fabrication stages,these variables would be assigned Table1

Group classification scheme—value of variables

Group Modularity Customer involvement

Design r Assembly r Design r Assembly r

fabrication use fabrication use

1,Fabricators q"q"

2,In?ol?ers y q q"

3,Modularizers q"y q

4,Assemblers y q y q

to Group1,Fabricators.If the variables assigned for both customer involvement and modularity were from the assembly and design stages,the case would be assigned to Group4,Assemblers.The classification of194companies resulted in126mass customizers: 77Fabricators,15In?ol?ers,17Modularizers and 17Assemblers.

6.2.Industry effects

The groups were tested to determine the effects of industry on group https://www.wendangku.net/doc/df16586466.html,ing SIC codes, plants were grouped into similar SIC classifications. SIC data were available for116of the126mass customizers.A Chi-square test of group membership

?. and SIC category was not significant p s0.56. Therefore,group membership is not related to indus-try classification.

7.Manufacturing context of typology

After the mass customization types were explic-itly identified,the groups were examined to fulfill the third purpose of the study—to explore the different manufacturing approaches to mass cus-tomization implied by the typology.The conceptual model allows for different implementations of a mass customization strategy.As described in previous sec-tions,three categories of variables were selected to represent the A mass B and A custom B components of a manufacturing system:process choice,planning techniques and technology.For descriptive purposes, an ANOVA with post-hoc Scheffe’s test was used to

′

determine the differences of the variables between

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R.Duray et al.r Journal of Operations Management182000605–625 620

groups.Table2shows the group means and ANOVA significance levels of these variables.Significant dif-ferences exist between the groups for at least one variable in each of the categories of process choice, technology,production planning,and performance at the0.05alpha level.This implies that there are differences in the manufacturing implementation of mass customization between the groups.7.1.Process choice

The mass customization types use different pro-cesses to achieve their mass customization capabil-ity.Significant differences exist between the groups for percent of components manufactured using line processes and the percent of components that are purchased,but not for job shop and batch processes.

Table2

Summary of ANOVA four-group matrix—significance of differences between group means of manufacturing system variables Variables p-value,Group1,Group2,Group3,Group4,n s126 one-way Fabricators In?ol?ers Modularizers Assemblers

?.?.?.?.

ANOVA n s77n s15n s17n s17

Process choice

Job0.119 3.5 4.27 3.5 2.59124 Batch0.881 3.57 3.67 3.31 3.82124

))))

?.?.?.

Line0.000 2.723,4 2.86 4.441 4.561120

))

?.?.

Purchased0.012 2.93 3.503 1.752 2.59123

Process control

?

?.?.?.

MTS0.013 2.704 3.73 2.234? 4.001?,3?113 ATO0.309 5.89 6.33 5.54 5.20118

))

?.?.

MTO0.008 6.414 6.33 6.36 5.131121 JIT0.503 4.17 4.47 3.33 4.20111 Technology

Design

))

?.?.

CAPP0.011 2.96 4.133 1.672 2.47123

))))))

?.?.?.

CAD0.000 5.933 6.003 4.051,2 5.06126 CAE0.430 3.84 4.07 3.29 3.06125 Manufacturing

CAM0.394 3.74 3.71 3.00 3.00124 CNC0.109 4.28 3.20 3.33 3.47124

?.?.

Robotics0.009 1.67 2.43 1.253 2.594122 Group Technology0.143 2.36 3.47 2.20 2.31119 Real-time process controls0.071 2.79 3.27 1.56 2.88122

))

?.?.?.

FMS0.011 3.092? 4.471?,3 2.132 3.29121 Bar coding0.173 3.09 3.33 1.88 3.31122 Administrative

?.?.

EDI0.046 3.20 4.074? 2.56 2.192?122

))

?.?.

MRP0.042 4.972 6.531 4.75 5.29124 DSS0.872 2.28 2.60 2.47 2.63116 Knowledge-based0.687 2.43 2.47 2.50 2.53117

))

?.?.?. Performance0.000y0.16240.557y0.0024?0.8131,3?126 )Significant differences between groups at a s0.05.

))Significant differences between groups at a s0.01.

?Significant differences between groups at a s0.10.

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Fabricators exhibit a significantly lower level usage of line processes in the manufacturer of components than Modularizers and Assemblers.Fabricators are the mass customization type that most closely mir-rors pure customization.Therefore,this limited use of line processes for component manufacturer in the Fabricators is not surprising.Fabricators,by defini-tion,provide customization through fabrication of distinct components.This custom fabrication would increase the need for more flexible manufacturing methods than the traditional line manufacture of components.

Assemblers have been described as the mass cus-tomizer that most closely resembles mass producers. Assemblers have the highest usage of line processes, which is consistent with their similarity to mass producers.Therefore,the use of line manufacture by Assemblers is expected.Modularizers also incorpo-rate line manufacturer into their manufacturing sys-tems.Modularizers and Assemblers share customer involvement in the late stages of the production cycle,but Modularizers utilize modularity in the early stages of the production cycle.Modularizers may use modules to provide component commonal-ity without providing customization until the cus-tomer is involved in the later stages.

In?ol?ers have the highest usage of purchased components and show significant difference with Modularizers.These two groups do not share cus-tomer involvement or modularity dimensions,but neither group has matched involvement of customer and modularity dimensions in the production cycle. In?ol?ers have customer involvement early in the process and modularity later in the production cycle while Modularizers exhibit the opposite character-istics.Perhaps for In?ol?ers,the early customer in-volvement allows time for the purchase of compo-nents for specific customer.

7.2.Production control

The use of process control techniques mirrors the anticipated usage by mass customization type.As-semblers,the mass customizer that most closely resembles mass producers,have the highest usage of

?.

make-to-stock MTS planning systems.Assemblers differ significantly in their usage levels of MTS from Fabricators and Modularizers,both of which utilize modularity early in the production process.In addi-tion,Fabricators,the mass customizers that most closely resemble pure customizers,have the highest usage in MTO planning systems,which differs sig-nificantly from the Assemblers.The use of process control techniques follows the anticipated usage for Assemblers and Fabricators.It should be noted, however,that if the raw scores are examined,all mass customizers utilize high levels of MTO and ATO planning technique and moderate levels of JIT in their manufacturing system.This high usage level of MTO r ATO control techniques is expected.By definition,all mass customers should have customer involvement specifying the product’s attributes at some point in the production cycle.This customer involvement would require the use of production to order and not to stock.

7.3.Technology

Mass customizers differ in their usage of technol-ogy.At least one variable differs significantly across the groups for design,manufacturers and administra-tive technologies.For design technologies,the group Modularizers is significantly different from Fabrica-tors and In?ol?ers.Modularizers have significantly lower usage of CAD technologies than Fabricators and In?ol?ers.The conceptual model suggests that Fabricators and In?ol?ers have customer involve-ment in the design and fabrication stages of the production cycle while Modularizers have customer involvement in the assembly and use stages.It ap-pears that mass customizers employ CAD technol-ogy when customers are involved in the early stages of production.The use of design technologies,such as CAD,to manage the customer specifications in these stages should be expected.When customers are involved early in the process,more resources may be required to manage the design function.

However,use of CAPP differs between In?ol?ers and Modularizers with In?ol?ers exhibiting the highest usage of CAPP technology.Once again,this finding is expected since In?ol?ers have early cus-tomer involvement that must be planned and man-aged through the assembly stages of production.This arrangement would require the use of CAPP tech-nologies.Unexpectedly,the third design technology ?.

variable CAE did not reflect any differences among

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the groups.The raw scores for these variables reflect low levels of usage of CAE.Groups using modular-ity in the early production stages require modules to be altered and,therefore,may rely on CAD for design purposes.Perhaps,the emphasis on CAD technologies supplants the use of CAE technologies for these mass customizers.

For manufacturing technologies,the most signifi-cant differences between the groups can be seen in the usage of flexible manufacturing technologies ?.

FMS.The highest users of FMS technology are In?ol?ers—the mass customizer with customer involvement early in the production stage and modu-larity employed at later stages.The In?ol?ers have significant difference in FMS usage than both Fabri-cators and Modularizers,both which have modular-ity early in the process.This indicates that if cus-tomers are involved prior to the usage of modularity, mass customizers are adopting a higher level of FMS usage.This result is not unexpected.FMS usage may replace the more traditional forms of modularity in the early stages of production.FMS modularity is gained through modularity of programs and replica-tion of design aspects between products.The flexibil-ity of this technology to quickly change part types allows customer to specify more aspects of a product than may not be captured with the concepts of modularity presented in this study.

Robotics usage also differed across the mass cus-tomizing groups.Assemblers have the highest usage while Modularizers have the lowest usage.How-ever,the raw scores for both groups are less than three,which would indicate Robotics usage on less

?

than of32%of products.Note:The questions an-chored the raw scale score responses to percentages of usage.The seven-point Likert scale was anchored at1with A not used—0%B,at4with A used for some orders—50%B,and at7with A used for all orders—100%B.A score of3is approximately .

32%.This does indicate a greater usage of Robotics in Modularizers than Assemblers,although no sig-nificant conclusions should be drawn from this fact. The other manufacturing technology variable,CAM, CNC,Group Technology and Bar coding,do not show significant differences between the groups. However,these variables can give us a richer picture of the mass customizers.The low level of usage of these technologies by all the mass customizers in the study may signify their lack of importance to the implementation of mass customization.

Administrative technology usage also differs among mass customizers.Assemblers have signifi-cantly lower usage levels of EDI than In?ol?ers. Both these groups have modularity in the later stages of the production process,but differ on the customer involvement.The higher usage level of EDI by In?ol?ers may correspond to an earlier involvement of customers.This finding would not be surprising if the electronic communication medium is used for customer interaction.However,this study cannot confirm the usage of EDI with customer as opposed to suppliers.

The usage of MRP system also differ among the groups with In?ol?ers exhibiting the highest usage while Modularizers and Fabricators exhibit lower levels of usage.In?ol?ers have the highest usage level,and although not significant,Assemblers have the second highest usage levels.In?ol?ers and As-semblers share modularity in the later stages of production.It is not surprising that these mass cus-tomizers would use MRP technologies to plan for the use of the modules in the assembly and use stages of the production cycle.

7.4.Financial performance

Business performance varies both within and across mass customizer configurations.Both high and low performers are practicing mass customiza-tion in each of the groups.Significant differences in the financial performance factor exist between the groups,with Assemblers displaying a significantly higher group mean for performance than Modulariz-ers and Fabricators.In?ol?ers also exhibits high performance when measured as a group mean.Both Assemblers and In?ol?ers have modularity in the later stages of production,but differ on point of customer involvement in specifying the product.Al-though no significant difference is seen between the performance means of Modularizers and In?ol?ers, differences do exist between Modularizers and As-semblers.The use of modularity in the later stages of production may point to increased performance for mass customizers.

The findings with respect to business performance of companies adhering to each of the mass cus-

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R.Duray et al.r Journal of Operations Management182000605–625623

tomization types provide valuable insights for com-panies pursuing mass customization.There appears to be a performance difference among companies pursuing mass customization based on the type of modularity https://www.wendangku.net/doc/df16586466.html,panies using modularity in the assembly and use stages exhibit higher perfor-mance than those using modularity in the design and fabrication stages.This suggests that those mass customizers that are closest to mass producers in manufacturing approach are most likely to reap the benefits of mass customization.Perhaps,these mass customizers that best able to achieve scale economies while delivering a customized product will exhibit better financial performance than those that do not. However,this alone may not guarantee high https://www.wendangku.net/doc/df16586466.html,panies should be aware that high-perfor-ming companies are found across the spectrum of all types of mass customization.

8.Summary and conclusions

This study develops a conceptual typology of mass customization that provides an explicit means for identifying and categorizing mass customizers from the perspective of operations.We suggest that two variables are key in classifying mass customiz-ers:the point in the production cycle where the customer is involved in specifying the product and the type of modularity used in the product.We validate the conceptual types empirically using data from a sample of mass customizers.

We also suggest and demonstrate broader config-urations of mass customization.Specifically,the dif-ferent approaches to mass customization implied by the typology were examined to provide a richer picture of the manufacturing systems employed.Pro-cess choice,planning techniques,and technology variables were examined as well as business perfor-mance.We demonstrate that mass customizers do differ on each of these dimensions based on their mass customization type.Most particularly in this typology,those mass customizers that theoretically resemble mass producers,Assemblers,choose manu-facturing systems that use line processes,incorporate the highest levels of MTS planning methods and utilize MRP.Fabricators,those mass customizers that most closely resemble craft producers,have the highest levels of MTO planning systems and high usage levels of CAD.The commonality of the manu-facturing systems among mass customizers is also noteworthy.All mass customizers use some form of a MTO or assemble-to-order planning system,incor-porate some form of batch processing and a majority of the products are made using CAD technology. This finding is not surprising.The use of CAD technology may be required to manage the A custom B portion of the order in an efficient cost-effective manner.Batch processing may provide the A mass B production of common modules.Then,the overall production process is managed using MTO and as-semble-to-order planning systems.The differences and commonalties among these mass customization groups provide a rich description of mass customiza-tion manufacturing systems.

Although both high and low performers are found among all mass customization types,we do discern better business performance among the types that use standard modules and employ modularity in the later stages of the production cycle.

8.1.Limitations and future research

This study has only begun to explore mass cus-tomization as a manufacturing phenomenon.This study takes a step forward in mass customization research by providing a conceptual model of mass customization and substantiating this model through an empirical investigation.However,this empirical exploration provides a one-time snapshot of com-pany practices.A natural extension of this research, and most empirical work in manufacturing strategy, is a longitudinal examination of companies.Manu-facturing systems are ever changing and a time lag may exist between making a decision on manufactur-ing priorities and realizing the related manufacturing capability.A longitudinal look at mass customizers would clarify the issues relating to the implementa-tion of this strategy in practice.

This study neglects to include the use of service as a mass customization technique.In addition to customizing product attributes,products may be mass-customized through the availability of cus-tomizable services.Manufacturers are increasingly looking to expand their product offerings through the

?addition of service to the product package Wise and

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R.Duray et al.r Journal of Operations Management182000605–625 624

.

Baumgaretener,1999.Services may also be modu-larized and may provide another avenue for mass customization.Future research may wish to include services as part of the mass customization model.

In addition,this study only investigates the cus-tomized portion of company’s product lines.The integration of customized and standardized products is not examined.Mass customization may enhance overall firm performance,including the design and production of standard products,through information gained regarding customer preferences.The relation-ship of mass customization to the entire organization may play a critical role in the success of a mass customization strategy.Therefore,the scope of mass customization research should be broadened to in-clude both mass-customized and standard products.

This paper has broadened the conceptual model of mass customization and its manufacturing implica-tions,but has neglected to make any specific value judgments to the inherent worth of mass-customized products.Future studies may wish to explore the market implications of mass customization,the ac-companying customer benefits,the effects of choice on customer satisfaction,and the costs associated with the implication of mass customization practices.

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(完整版)Agilent1260液相色谱系统操作规程

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6.1.5.1供试品用规定溶剂配制成供试品溶液。 6.1.5.2定量测定时，对照品溶液和供试品溶液均应分别配制 2份。 6.1.5.2如有必要，样品需预处理，如过滤等，以免对色谱系统产生污染和色谱干扰。 6.1.6选择色谱柱： 6.1.6.1根据待检供试品的检测方法确定所需的色谱柱； 6.1.6.2检查仪器上安装的色谱柱是否与其相同，若不同则需进行更换。 6.1.7更换色谱柱 6.1. 7.1拆卸原色谱柱： 先握住色谱柱，再松动色谱柱出口端螺帽，取下出口端的管线； 松动色谱柱入口端螺帽，取下入口端的管线； 用止动塞将色谱柱的进出口塞住拧紧后，将色谱柱放回原专用包装盒内 6.1. 7.2安装新色谱柱： 从专用包装盒内取出色谱柱，松动并取下色谱柱出入口的止动塞； 将与进样器相连的管线一端插入色谱柱入口端，拧紧螺帽； （注意：安装时色谱柱上的流向标志应与管路的流动相流向一致。 ） 将与检测器相连的管线一端插入色谱柱出口端，拧紧螺帽。 6.2开机 6.2.1通电前应检查仪器设备之间的电源线、数据线和输液管道是否连接正常。 6.2.2接通电源，打开计算机和打印机开关 6.2.3等待计算机自检完毕后，进入 Windows 桌面，依次打开泵、进样器、检测器各模块电源。 打开柱温箱开关。 6.2.4待各模块自检完成后，点击 6.2.5确定仪器与工作站已连接，若未连接，需关闭工作站，重新连接。注意必须先打开检测器, 再连接 工作站。 6.2.6从“视图”菜单中选择“方法和运行控制”画面 ，也可单击工作站画面左侧的“方法和运行 控制”项，进入方法和运行控制窗口。 6.3 操作 6.3.1泵的开启和设置 6.3.1.1打开Purge 阀（逆时针），右键点击四元泵下面的空白处，选择“方法”选项，进入泵 编辑画面。 Win dows 桌面 lc ”图标进入化学工作站画面

金黄色葡萄球菌感染的病因有哪些

如对您有帮助，可购买打赏，谢谢 生活常识分享金黄色葡萄球菌感染的病因有哪些 导语：金黄色葡萄球菌感染是皮肤化脓性感染的最常见致病菌，也是四种最常见的医院获得性感染的病原之一。其传播方式在医院内部主要是经健康医务人 金黄色葡萄球菌感染是皮肤化脓性感染的最常见致病菌，也是四种最常见的医院获得性感染的病原之一。其传播方式在医院内部主要是经健康医务人员暂时寄居细菌的手进行传播，尤其是在新生儿童症监护病房(NICU)金葡菌是最常见的毒力最强的致病原。那么金黄色葡萄球菌感染的病因有哪些呢？看过下面的文章相信你就会明白。 金黄色葡萄球菌脑膜炎是指由金黄色葡萄球菌引起的脑膜炎，起病急，常有全身感染中毒症状，如畏寒、发热，伴持久而剧烈的头痛，颈强直较一般脑膜炎明显，除有脑膜炎症状外，尚有局部感染病灶，败血症患者还有其他迁徙性病灶，出现皮疹，如荨麻疹样、猩红热样皮疹或小脓疱疹，皮肤可见出血点，很少融合成片。 金黄色葡萄球菌引起的脑膜炎多继发于金葡菌败血症，尤其多见于合并左心内膜炎的患者，通过细菌栓子经血流侵袭脑膜。面部痈疖并发海绵窦血栓性静脉炎可进一步导致脑膜炎，颅脑损伤、颅脑手术后及腰椎穿刺时消毒不严也可并发脑膜炎。脑膜附近的感染病灶如中耳炎，乳突炎、鼻窦炎等亦可引起本病，新生儿脐带和皮肤的金葡菌感染也可继发脑膜炎，发病时间多在产后2周左右。 金黄色葡萄球菌感染的病因有哪些呢？上面的内容已经让我们知道了答案.为了您和家人的健康，如有发现类似感染的症状请及时就医，如果您还有什么需要咨询的请随时向我们提问，我们的专家24小时在线回答您的问题接军您的疑惑给您提供一个最佳的治疗方案，相信一定能给您满意的答复。

安捷伦液相使用方法

高效液相色谱仪的使用方法2008-05-11 20:24仪器名称：高效液相色谱仪 仪器型号：Agilent 1100 生产厂家：Agilent 使用方法： (一)、开机： 1、打开计算机,进入Windows NT （或Windows 2000）画面,并运行Bootp Server程序。 2、打开1100 LC 各模块电源。 3、待各模块自检完成后，双击Instrument 1 Online图标，化学工作站自动与1100LC通讯，进入的工作站画面如下所示。 4、从“View”菜单中选择“Method and Run control”画面, 单击”View”菜单中的“Show Top Toolbar”，“Show status toolbar”，“System diagram”,”Sampling diagram”，使其命令前有“√”标志，来调用所需的界面。 5、把流动相放入溶剂瓶中。 6、打开Purge阀。 7、单击Pump图标，出现参数设定菜单，单击Setup pump选项，进入泵编辑画面。 8 、设Flow：5ml/min，单击OK。 9、单击Pump图标，出现参数设定菜单，单击Pump control选项，选中On，单击OK，则系统开始Purge，直到管线内（由溶剂瓶到泵入口）无气泡为止,切换通道继续Purge，直到所有要用通道无气泡为止。 10、单击Pump图标，出现参数设定菜单，单击Pump Control选项，选中Off，单击Ok关泵，关闭 Purge valve。 11、单击Pump图标，出现参数设定菜单，单击Setup pump选项，进入Pump编辑画面，设Flow：1.0ml/min。 12、单击泵下面的瓶图标，如图所示（以二元泵为例），输入溶剂的实际体积和瓶体积。也可输入停泵的体积。单击Ok。 （二）数据采集方法编辑： 1、开始编辑完整方法： 从“Method”菜单中选择“Edit entire method”项，如上图所示选中除“Data analysis ”外的三项，单击Ok，进入下一画面。 2、方法信息： 在“Method Comments”中加入方法的信息（如：方法的用途等）。 单击Ok 进入下一画面。 3、泵参数设定：（以二元泵为例） 在“Flow”处输入流量,如1ml/min，在“Solvent B”处输入70.0,(A=100-B) ,也可Insert 一行”Timetable”,编辑梯度。在“Pressure Limits Max”处输入柱子的最大耐高压，以保护柱子。单击Ok进入下一画面。 4、自动进样器参数设定: 选择合适的进样方式, 如图所示，进样体积1.0ul ,洗瓶位置为6号。“Standard Injection”----只能输入进样体积，此方式无洗针功能。“Injection with Needle Wash”----可以输入进样体积和洗瓶位置，此方式针从样品瓶抽完样品后，会在洗瓶中洗针。“Use injector program”---可以点击Edit 键进行进样程序编辑。

agilent高效液相色谱仪标准操作程序

Agilent 1200高效液相色谱仪标准操作程序 1.目的 使操作人员的操作步骤规范化. 2.适用范围 适用于仪器安装、调试、校准后正常状态下进行的操作. 3.责任者 质控科仪器分析员对此规程负责. 4.规程 4.1清洗液、流动相、封柱液预处理 4.1.1所有清洗液、流动相、封柱液在使用前均需过滤、脱气以及混合均匀. 4.1.2甲醇-水（10：90）、乙腈-水（10：90）、超净水、乙腈均需存放在棕色溶剂瓶中. 4.1.3含有乙腈的溶液以及不含乙腈但含有较高比例的其他有机溶剂的溶液在过滤时需使用有机相微孔滤膜，其它溶液在过滤时需使用水相微孔滤膜. 4.1.4存放清洗液、流动相、封柱液的溶剂瓶在每次装入溶液前需用少量过滤好的该溶液清洗数次. 4.2接通电源，开启连机电脑，再接通仪器电源，仪器自检完毕，处于准备进行状态.双击桌面图标“仪器1联机”，打开Agile nt 1200化学工作站，在左上角下拉框中选择“方法与运行控制”界面.显示如下图

标: 燈InatEU-ent I :方払和铤乔哲制 注意：一定要先双击“仪器1联机”图标，进入联机状态，方可双击“仪器1脱机”图标，同时进入脱机界面?否则，将无法联机. 4.2泵421准备清洗液并装入溶剂瓶中，将吸滤器放入瓶内.安装所需用柱子. 4.2.3将吹扫阀（即“Purge”阀）打开，单击泵图标—" 选择“设置泵”，将“流速”设置为3.00ml/min.选择清洗液所在通道（建议为A通道），单击“确定”，在“系统视图”中单击“启动” 运行泵，泵运行10分钟后，观察压力，应小于10bar,若大于此压力，应更换purge阀滤芯，调节流速1.00ml/min.

Agilent1200型高效液相色谱仪操作手册

Agilent 1200 LC （中文版 B01.01） 现场培训教材 安捷伦科技有限公司 生命科学与化学分析仪器部

一、培训目的： ●基本了解1200LC硬件操作。 ●掌握化学工作站的开机，关机，参数设定,学会数据采集,数据分析的基本操作。 二、培训准备： 1、仪器设备：Agilent 1200LC ●G1310A :(单元泵)；G1312A(二元泵)；G1311A(四元泵)。 ● G1313A（标准型自动进样器）。 ● G1316A（柱温箱）。 ● G1314A（VWD检测器）。 ● G1362A（示差检测器）。 ●色谱柱: Eclipse XDB-C18 150 x 4.6 mm, 5um column P/N 993967-902 2、溶剂准备： ●色谱级纯或优级纯乙腈或甲醇。 ●二次蒸馏水

基本操作步骤: (一)、开机： 1、打开计算机,进入中文Windows XP画面,并运行CAG Bootp Server程序。 2、打开 1200 LC 各模块电源。 3、待各模块自检完成后，双击“Instrument 1 Online”图标，化学工作站自动与1200LC 通讯，进入的工作站画面如下所示。 4、从“视图”菜单中选择“方法和运行控制”画面, 点击“视图”菜单中的“显示顶部工具栏”，“显示状态工具栏”，“系统视图”,“样品视图”，使其命令前有“√”标志，来调用所需的界面。 5、把流动相放入溶剂瓶中。 6、打开冲洗阀。 7、点击“泵”图标，点击“设置泵…”选项，进入泵编辑画面。 8 、设流速：5ml/min，点击“确定”。 9、点击“泵”图标，点击“控制…”选项，选中“启动”，点击“确定”，则系统开始冲洗，直到管线内（由溶剂瓶到泵入口）无气泡为止,切换通道继续冲洗，直到所有要用通道无气泡为止。 10、点击“泵”图标，点击“控制…”选项，选中“关闭”，点击“确定”关泵，关闭冲洗阀。 11、点击“泵”图标，点击“设置泵…选项”，设流速：1.0ml/min。 12、点击泵下面的瓶图标，如下图所示（以单元泵为例），输入溶剂的实际体积和瓶体积。也可输入停泵的体积，点击“确定”。

金黄色葡萄球菌

金黄色葡萄球菌研究现状 前言 金黄色葡萄球菌(Staphylococcus aureus ,金葡菌)是一种革兰氏 阳性球菌,广泛分布于自然界,可以引起人和动物的感染。在人体主要寄殖于鼻前庭粘膜、腹股沟、会阴部和新生儿脐带残端等部位，偶尔也寄生于口咽部、皮肤、肠道及阴道口等，是医院感染常见的病原体之一。在医院里，耐甲氧西林和其它抗生素的金葡菌广泛流行，对万古霉素不敏感的菌株也有所增加，给临床治疗带来了很大的困难。金葡菌除了引起感染外，其产生的肠毒素可污染食物而致食物中毒，为人类带来非常严重的公共卫生负担。本文拟对金葡菌感染的临床症状，流行病学研究，病原学，分型，检测及预防等方面做简要综述。 1.病原学 1.1形态与染色 典型的金黄色葡萄球菌为球型,直径0.8μm左右,显微镜下排列 成葡萄串状。金黄色葡萄球菌无芽胞、鞭毛,大多数无荚膜。革兰染色阳性,衰老或死亡后可转为阴性。 1.2培养特性 金黄色葡萄球菌营养要求不高,在普通培养基上生长良好,需氧或兼性厌氧,最适生长温度37 ℃,最适生长pH7. 4。平板上菌落厚、有光泽、圆形凸起,直径1～2mm。血平板菌落周围形成透明的溶血环。金黄色葡萄球菌有高度的耐盐性,可在10～15 %NaCl 肉汤中生长，因此利用它的这个特性进行污染标本分离。

1.3抵抗力 抗干燥:在干燥环境中存活数月；空气中存在,但不繁殖;耐热:加热70 ℃1h ,80 ℃30min 不被杀死；耐低温:在冷冻食品中不易死亡[1，2 ];耐高渗：在含有50 %～66 %蔗糖或15 %以上食盐食品中才可被抑制,能在15 %NaCl 和40 %胆汁中生长. 2．流行现状 2.1院内感染及耐药 金黄色葡萄球菌是院内感染的常见细菌之一，许多国家都设有专门机构，应对金葡菌的院内感染问题。随着?-内酰胺类抗生素的广泛应用，耐甲氧西林金黄色葡萄球菌(MRSA) 随之增加，且引起的感染和病死率有逐年增加的趋势。MRSA 可通过接触途径进行传播, 即易感人群从携带者或感染者身上获得MRSA , 导致传播流行。 美国第一例MRSA 发现于1968 年, 1975 年MRSA 在临床分离出的金葡菌中仅占2. 4% , 而1991 年则迅速增至29% [3 ]。现在美国的某些医院MRSA 在临床分离出的金葡菌中可以占到30%-50%。同样在欧洲的葡萄牙和意大利，MRSA 在临床分离出的金葡菌中占50%；土耳其和希腊>30%[4]。荷兰非常低，只有2%，这归功于荷兰人行之有效的控制策略[5]。在欧洲的调查中，瑞士的流行率最低（1.8%）[4]，这主要由于他们在医院内实行了一些新的干预行为，如坚持医护人员的手部卫生管理，以减少MRSA的传播[6]。在北欧国家MRSA 在临床分离出的金葡菌中不足1%[7]。在芬兰MRSA是非常少见的，直到20世纪90年代医院的病人中只有散发的病例[8][9]，

安捷伦1260型高效液相色谱仪详细操作规程

1.目的：规范Agilent 1260高效液相色谱仪维修、保养、校正操作。 2.适用范围：本公司化验室Agilent 1260高效液相色谱仪的维修、保养。 3.有关责任：化验室精密仪器室 4.引用标准：仪器说明书及Agilent化学工作者现场操作培训教材 5.规程内容： 5.1开机前准备 5.1.1根据实验要求配制流动相，须经0.45μm滤膜过滤，之后再进行脱气处理，使用前必须用超声波振荡l0-15min，按无机相和有机相分开别装入溶剂瓶A（装有洗盐装置，最好固定盛放无机盐水相）、B中；对照品和样品溶液进样前要经0.45μm滤膜过滤。 5.1.2若流动相中含有缓冲盐,则必须以每分钟2～3滴的速度虹吸10%的异丙醇水冲洗seal-wash，以防有盐结晶在泵头产生而损坏泵头。 5.2.采样前准备 5.2.1打开计算机,进入 Windows 系统, 从上到下依次打开各模块电源。5.2.2待各模块自检完成后，双击桌面上的“仪器1联机”图标，将自动进入化学工作站画面。 5.2.3从“视图”菜单中选择“方法和运行控制”画面,也可单击工作站画面左侧的“方法和运行控制”项，进入方法和运行控制窗口。 5.2.4打开Purge阀（逆时针），右击“泵”图标出现参数设定菜单单击“设定泵”选项进入泵编辑画面。 5.2.5设“流量”逐步增大流速至5ml/min ，A通道设到100%，单击“确

定

”。 5.2.6单击“泵”图标，出现参数设定菜单，单击“泵控制“选项选中“开”单击“确定”则系统开始Purge，直到管路内由溶剂瓶A到泵入口无气泡为止；切换B通道(B通道设到100%)继续Purge直到所有通道管路内均无气泡为止。(查看柱前压力，若大于10Bar，则应更换排气阀内滤芯/过滤白头。) 5.2.7将泵的流量设到0.5ml/min，若使用双泵则应设定溶剂配比，如A=80%，B=20%；关闭排气阀（顺时针）；再将流量设到0.8ml/min，2分钟后设定至方法所需流速，冲洗色谱柱20-30min。 5.2.8单击泵下面的瓶图标，输入溶剂瓶A、B内流动相的实际体积（为保护泵和色谱柱，请按实际体积输入）和停泵的体积单击“确定”，如果各溶剂瓶溶剂体积小于停泵体积，泵将自动停止。 5.2.9把缓冲液（用于柱子过渡的，与流动相等比例的乙腈/水、甲醇/水或10%的水溶液）换成流动相，排气后，逐步增加至所需流速，待柱压基本稳定后，打开检测器等，观察基线情况。 5.3.数据采集 5.3.1采集方法编辑 5.3.1.1编辑完整方法：从“方法”菜单中选择“编辑完整方法”项，选中除“数据分析”外的三项，单击“确定”进入下一画面。 5.3.1.2方法信息：在“方法注释”栏中加入（如方法的用途等），单击“确定”进入下一画面。

金黄色葡萄球菌

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金黄色葡萄球菌感染八 葡萄球菌（staphlococcus）是常见的化脓性球菌，寄生在大多数人的皮肤上，常引起皮肤、软组织感染，细菌可侵入淋巴管及血液，引起危及生命的败血症及严重的转移性感染如心内膜炎、关节炎、骨髓炎、肺炎、脑膜炎等。某些金葡菌可产生毒素，引起皮疹或多系统功能障碍，如中毒性休克综合征。凝固酶阴性的葡萄球菌，特别是表皮葡萄球菌，是院内感染的重要致病菌，腐生葡萄球菌是泌尿道感染的常见致病细菌。 【病原学】 葡萄球菌属微球菌属，革兰阳性球菌，呈葡萄状排列，故名为葡萄球菌。已知葡萄球菌属有20余种，造成人群感染者有10多种，其中金葡菌、表葡菌及腐生性葡萄球菌（腐葡菌）为常见致病菌。此外溶血性葡萄球菌、糖发酵葡萄球菌、人葡萄球菌等也可致病，但很少见。葡萄球菌可用噬菌体、血清、生化反应、对抗生素的敏感性及质粒指纹图谱等方法分型。大多数金葡菌可为噬菌体裂解，表葡菌对噬菌体不敏感，故噬菌体分型仅用于金葡菌。此种分型对流行病学调查，追踪传染源、研究型别与感染种类及耐药性等有重要价值。金葡菌的致病性最强，主要因其产生多种毒素和酶有关。

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