Product Variants

To plan for variety, a company must first ascertain the number of variants of a product it would like to introduce, and the numbers of options per module to support this level of variety. A product typically has a fixed number of module-types such as brake system, fuel system, and transmissions, in case of a car. Each module-type may have several module-options depending on the choice of components, part geometry, and manufacturing processes. If a product comprises three module-types A, B, and C) with the number of module-options in each being Na, Nb and Nq respectively, the total number of possible product variants would be (NjdiNsWc). 

The modules are produced in a proactive mode because they can be preassembled. So manufacturing or component-assembly is not a bottleneck for mass customization with modular products. If products can be designed so that the customers can configure the modules themselves (such as configuring a home music system), the supply chain can be greatly simplified. 

ITT Automotive has applied the modularity concept in designing the antilock braking system (ABS) module (Pisano 1994). Components such as pump, valve block, and motor together form a module-option for the ABS Fig. 3.3 shows four such options (Mi to M4). The ABS options Mj are created by choosing from an assortment of each of these components. For example, the ABS M2 includes the pump pi, valve V2, and motor t2 M2 = ipiAidi)- Each option fitted to the end product creates a product variant. For example different car models can be fitted with different ABS configurations, and so can trucks and SUVs. In Fig. 3.3, two car variants are shown with ABS options Mi and M3, and the two truck variants have ABS options M2 and M4. 

In Fig. 3.3, the implied assumption is that M2 and M4 are not compatible with product 1 (car), and Mi and M3 are not compatible with product 2 (truck). 

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Below, the procedure for the determination of dominant campaigns in a version that was proposed by Lazaro et al. (1989) is outlined. Their methodology includes enumeration of feasible production sequences, selection of dominant production lines, task sequencing, and search for an optimum with constraints. All possible production variants are generated by an enumeration procedure that takes into account the possibility of available equipment working in parallel, initial and final task overlapping, and instability of intermediate products. Non-feasible sequences are eliminated so that only favourable candidates are subjected to full evaluation. Dominant production lines are selected by maximizing the criterion ... 

Size-exclusion HPLC (SE-HPLC) separates proteins on the basis of size and shape. As most soluble proteins are globular (i.e. roughly spherical in shape), separation is essentially achieved on the basis of molecular mass in most instances. Commonly used SE-HPLC stationary phases include silica-based supports and cross-linked agarose of defined pore size. Size-exclusion systems are most often used to analyse product for the presence of dimers or higher molecular mass aggregates of itself, as well as proteolysed product variants. 

Commodity vs. specialty is not only related to product properties from a company-internal perspective but also to the business associated with this product. The management of commodities is less focused on product complexity as in the case of specialties, e.g. related to product variants, packaging and small volumes. It is more related to manage large volumes and values as well as prices. Consequently, the differentiation of commodities and specialties impacts the management of the value chain significantly. 

Product-related substances are molecular variants of the desired product formed during manufacture and storage, which are active and have no deleterious effect on the safety and efficacy of the drug product.2 Many recombinant protein products are inherently heterogeneous, mixtures of closely related structures or product variants. These variants possess properties comparable to the desired product and are not considered impurities. It is only when they do not have properties of the desired product that their presence is problematic. 

Product variants are generated by a number of genetic, chemical, and physical changes ... 

Genetic changes can give rise to product variants by mutations in the product-encoding gene itself. 

Product variants can also be the result of action of cellular proteins on the drug molecule, such as proteolytic processing inside and outside cells. Enzymes from the host cell can make modifications of the product protein. 

Product variants can also be generated by in-process procedures, such as those used for viral inactivation, for example. These procedures could alter the protein structure, forming new epitopes. These types of changes could potentially be detected by ELISA because of the specificity of the antigen-antibody interaction. In the case of vaccine production, an ELISA could be used to monitor viral inactivation. For this, a panel of MAbs, if available, could be used. 

The ELISA is an appropriate method to detect some, but not all, of these product variants. The reactivity of antibodies is not affected much by glycosylation of the antigen. An ELISA would not be the most appropriate method to analyze product variants due to differences in glycosylation. ELISA would be appropriate for analysis of variants, such as aggregates, that contain a different protein structure that can be specifically recognized by an antibody. 

According to current PDA guidelines, an acceptable pharmaceutical product should exhibit less than 10% deterioration after 2 years.5 Protein biopharmaceuticals usually have to be stored under refrigerated conditions or freeze dried to achieve an acceptable shelf life. EL IS As for aggregates and product variants as discussed previously would be applicable for determining shelf life. 

And the number, location, capacity and technology of sites including allocation of products/product variants and markets to individual sites (partly determined by the chosen network design principles). 

Dedicated plants are designed specifically for production of a single product or a small range of product variants. Redesigning dedicated plants to produce a different product is usually not possible. 

A simplification of the production network redistributes product variants within the network to reduce the number of plants producing identical products. This leads to a reduction of the network s complexity and allows for economies of scale. Usually, no change of capacity and no change in the number and location of plants being part of the value chain s production network takes place. 

Secondary metabolism comprises the side paths of the ordinary metabolism, so-called primary metabolism which are activated in the cell in rest situations or under limiting conditions for nutrient and energy supply. In most cases, secondary metabolism is linked to the building blocks responsible for growth and reproduction which are products of primary metabolism and is hallmarked by a multitude of reactions, intermediates and final products. Starting materials for the secondary metabolism are e.g. amino acids, sugars and the co-enzymes of the primary metabolism. Only a very small fraction of formation mechanisms and the product variants of plant secondary metabolism have been characterized yet. 

At the completion of product optimisation, when the best product variant has been selected, it is a good idea to summarise the work conducted in a Product Optimisation Report. The report should reference the primary data from preformulation, product optimisation and stability studies, cross-referencing other investigational reports where necessary. It should clearly justify the recommendations for the quantitative formula and the excipient, component and product specifications. Such a document can be very useful to aid smooth technology transfer into production and for writing regulatory submissions. 

Mass spectroscopy (MS) has become an important tool in the analysis of biopharmaceuticals. The focus is less on routine application in QC, but in the structural characterization of products, variants, and... 

Flexible, modular assembly systems (see Figure 4) usually work in cycles of a few seconds and are often used for the automated assembly of product variants for large to medium numbers of units. The principle of the flex-link assembly stations is applied for flexible, modular assembly systems because this is the only way to realize flexibility in the linking of individual assembly stations. Longitudinal transfer systems are used as work transfer devices. In order to prevent individual cycle times, technical malfunctions, capacity fluctuations, and other factors of certain assembly stations from affecting the next stations, a buffer function in the transfer line between the assembly sta-... 

The different kinds of cases have various dimensions (six heights, three widths, and three depths). Altogether there are about 1,000 product variants with customer-specific fastening positions for the measuring instrument inserts. Therefore, the assembly line is divided into order-independent preassembly and order-specific final assembly (see Figure 41). 

A product family is a set of products that are derived from a common platform (Meyer and Lehnerd 1997). Each individual product within the family (i.e., a product family member) is called a product variant. While possessing specific features/functionality to meet a particular set of customer requirements, aU product variants are similar in the sense that they share some common customer-perceived value, common structures, and/or common product technologies that form the platform of the family. A product family targets a certain market segment, whereas each product variant is developed to address a specific set of customer needs of the market segment. 

Product Differentiation Product Structure Product Variants... 

The correlation of modularity and commonality is embodied in the class-member relationships. A product structure is defined in terms of its modularity where module types are specified. Product variants derived from this product structure share the same module types and take on different instances of every module type. In other words, a class of products (product family) is described by modularity and product variants differentiate according to the commonality among module instances. 

Dijferentiation enabler Differentiation enablers (DEs) are basic elements making products different from one another. They are the source of variety within a product family. From the customer perspective, DEs may be in the form of option features, accessories, or selectable feature values. In a computer, for example, while a CD drive is an optional feature (yes/no), the RAM must be one instance of a set of selectable feature values, such as 64K, 128K, and 256K bites. In the engineering view, DEs may be embodied in distinct structural relationship (structural DEs) and/or various modules with different performance (constituent DEs). Each engineering DE usually has more than one alternative applicable to product variant derivation for specific applications. 

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