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Product variant design process consists of a series of asynchronous activities. These activities and the logic relations among them are important in constructing general logic workflow structure, which is the foundation of deriving an activity path for variant design business. Traditional process modeling approaches have not defined activities for product variant design and cannot describe the complex relations among these activities because of the lack of logic express elements. Thus, logic workflow structure modeling method is anticipated to meet the requirements of logic description and path generation in product variant design application. This paper aims to address these issues.

The paper identifies the variant design modes of different types of parts and defines their variant design activities. The procedure of constructing general logic workflow structure of product variant design is proposed. Simultaneously, the principles of inferring logic relations among activities are put forward based on their adjacency information and connectivity probability. A general logic workflow structure of product variant design is constructed. Based on this, activity path corresponding to a variant design business can be generated. The algorithm of generating activity path is designed as well. In addition, Boolean vectors of activity path, based on the functional contour matrix of polychromatic set theory, can be inferred, which denotes the functional character of activity path.

A general logic workflow structure for product variant design has been established, which comprises variant design activities and basic process logic nodes. The logic relations among activities can be inferred based on their in-degree/out-degree and connectivity probability. The function character of activity path can also be expressed based on the polychromatic set theory.

The combination of variant design activity and basic process logic node makes diverse variant design business descriptions possible in a general workflow structure. The proposed approach provides evidences for designer to plan and develop product variant design system effectively.

Product variant design can only be achieved after all its constituent parts have been implemented by variant design. It is necessary to plan the sequence of part variant design reasonably. The product variant design process involves a large amount of information transfer events at the dimensional level. A reasonable product variant design process needs to make full use of the information transfer characters of parts to decrease the uncertainty of product variant design process. The existing methods of researching the product variant design process mainly focus on resource constraint and activity logic. They are deficient, however, in information transfer resolution and uncertainty management. This paper aims to address these issues.

This paper identifies the number of dimension transfer paths and the position of dimension locating within a transfer path as being the key factors affecting the information transfer role of dimension. Information transfer utility is proposed to measure the information transfer capability of dimensions and parts. Based on these, a two-stage approach of generating the sequence of part variant design based on information transfer utility is proposed.

The uncertainty of dimension constraint network is minimal during the product variant design process when parts are implemented by variant design under the sequence generated through a two-stage method based on the information transfer utilities of parts, as does the times of parameter transferring and iteration in dimension constraint network.

Part variant design under the sequence of descending information transferring utilities can decrease the difficulty of implementing product variant design validly and also increase the efficiency. This suggests an innovative method to planning the product variant design process reasonably from the perspective of informatics.

The purpose of this paper is to propose a new procurement strategy with the aim to achieve higher value for money (VFM) in public works delivery. Its main innovation lies in the possibility of optional submission of cost-efficient design variants by any interested contractor within the context of an open procedure. The final scope of works incorporates the variants approved, and all contractors are invited to submit a bid for the revised scope and budget.

This paper is a piece of applied research presenting the development of a new, cost-effective procurement strategy for public works, geared at the European Union (EU) legal framework. The strategy’s feature compilation has been based on comprehensive literature review while numerical data from a real world project were used to demonstrate its financial advantages.

The proposed strategy enables the delivery of the best value project at the lowest cost possible. This is achieved through ensuring high competition among competent contractors, improving the cost efficiency of technical solutions, discouraging future scope changes and establishing objectivity, fairness and transparency in the process of contract award.

The use of the proposed strategy results in public projects of enhanced VFM, reduced constructability issues and less scope changes during the construction stage.

The proposed strategy marks a new approach in procurement which enables the delivery of best VFM in public works. Therefore, it makes a valuable contribution towards the achievement of the overarching EU target for efficient public spending.

The transition to a circular economy in the built environment is key to achieving a resource-effective society. The built environment can be made more circular by applying circular building components. The purpose of this paper is to present a design tool that can support industry in developing circular building components.

The tool was developed and tested in five steps. In Step 1, the authors analysed existing circular design frameworks to identify gaps and develop requirements for the design tool (Step 2). In Step 3, the authors derived circular design parameters and options from existing frameworks. In Step 4, the authors combined and specified these to develop the “circular building components generator” (CBC-generator). In Step 5, the CBC-generator was applied in the development of an exemplary component: the circular kitchen and tested in a student workshop.

The CBC-generator is a three-tiered design tool, consisting of a technical, industrial and business model generator. These generators are “parameter based”; they consist of a parameter-option matrix and design canvasses. Different variants for circular components can be synthesised by filling the canvasses through systematically “mixing and matching” design options.

The developed tool does not yet support establishing causal links between “parameter-options” and identification of the most circular design variant.

The CBC-generator provides an important step to support the building industry in developing and implementing circular building components in the built environment.

Whilst existing tools and frameworks are not comprehensive, nor specifically developed for designing circular building components, the CBC-generator successfully supports the integral design of circular building components. First, it provides all the design parameters which should be considered; second, it provides extensive design options per parameter; and third, it supports systematic synthesis of design options to a cohesive and comprehensive circular design.

The purpose of this paper is to include thermal analysis in the design process of permanent magnet synchronous motor (PMSM). The additional objective is a comparison of PMSM with induction motor (IM) in terms of thermal phenomena.

Numerical investigation using commercial software MotorSolve was performed. Parameterized models of PMSM and IM were used. Calculations of motor parameters and temperature distribution were made using Finite Element Method.

The results of the calculations show that thermal calculations should be included in the design process because the maximum permissible operating temperature of permanent magnets should not be exceeded. A comparative analysis of PMSM and IM shows that the PMSM has better parameters than the IM which was used as a base of the PMSM construction.

Computational models should be verified experimentally on a physical model or by using more complex numerical models. In the case of IM thermal calculations, a method of air speed calculation should be proposed. Air speed is a parameter that is necessary in thermal analysis of IM, but during the design process it is unknown.

This paper presents modelling methodology of 3D transient thermal field coupled with electromagnetic field applied in a three-phase IM at rated load conditions. This paper presents a design strategy which includes thermal analysis of the designed PMSM. Moreover, the paper shows a comparison between PMSM and IM indicating advantages of PMSM over IM.

Beyond their functional utility products have a symbolic meaning. Parts of this symbolic meaning are accounted for by concepts like brand personality and product‐user image, which describe the symbolic meaning associated with the brand or product class. However, the physical product also carries symbolic meaning. That part of the symbolic meaning that refers to the physical product itself, and is described with human personality characteristics, is called product personality. The purpose of this article is to show that product personality positively influences consumer preference through a congruence effect.

A two‐phase study was conducted. In the first phase, product‐personality congruence was measured. The second phase was used to establish user‐image congruence.

The results indicate that people prefer products with a product personality that matches their self‐image. Moreover, this positive effect of product‐personality congruence is found to be independent of the user‐image congruence effect.

Previous research has shown that product variants can be designed to have a specific personality. This study has shown that product‐personality congruence has a positive effect on consumer preference.

The purpose of this paper is to present the results of the preliminary design and optimization of the air-intake system and the engine nacelle. The work was conducted as part of an integration process of a turboprop engine in a small aircraft in a tractor configuration.

The preliminary design process was performed using a parametric, interactive design approach. The parametric model of the aircraft was developed using the PARADES™ in-house software. The model assumed a high level of freedom concerning shaping all the components of aircraft important from the point of view of the engine integration. Additionally, the software was used to control the fulfillment of design constraints and to analyze selected geometrical properties. Based on the developed parametric model, the preliminary design was conducted using the interactive design and optimization methodology. Several concepts of the engine integration were investigated in the process. All components of the aircraft propulsion system were designed simultaneously to ensure their compliance with each other.

The concepts of the engine integration were modified according to changes in the design and technological constraints in the preliminary design process. For the most promising configurations, computational fluid dynamics (CFD) computations were conducted using commercial Reynolds-averaged Navier–Stokes solver FLUENT™ (ANSYS). The simulations tested the flow around the nacelle and inside the air-delivery system which consists of the air-intake duct, the foreign-particles separator and the auxiliary ducts delivering air to the cooling and air-conditioning systems. The effect of the working propeller was modeled using the Virtual Blade Model implemented in the FLUENT code. The flow inside the air-intake system was analyzed from the point of view of minimization of pressure losses in the air-intake duct, the quality of air stream delivered to the engine compressor and the effectiveness of the foreign particles separator.

Based on results of the CFD analyses, the final concept of the turboprop engine integration has been chosen.

The presented results of preliminary design process are valuable to achieve the final goal in the ongoing project.

The primary objective of this paper is to illustrate the development of an integrated product development environment using template‐based methodology. This system would thus act as an effective tool to reduce cost by foreseeing manufacturability constraints during concept generation phase. Concurrent engineering approach is applied to product and process development and thus the different phases of manufacturing are integrated together. The developed template system is then used for the design of a prototype using an electric motor.

In this paper, implementation of an integrated design based on templates is presented. The developed system components such as design calculations, component search, machine selection, process template retrieval and cost estimation. These components are integrated to relational databases. These databases contain all information required for integrated product and process development. Concepts used in developing the system are independent of the software used.

By using templates, the time required for new product development is drastically reduced. At the same time incorporating computer‐aided process planning into the system gives the designer a better understanding of the cost implications of the modified design with respect to manufacturing. The major challenge in implementing of such system is that any changes in the manufacturing facility have to be incorporated in the process plans stored. This can be a tedious job but can be overcome by using hybrid process planning approach instead of variant based approach.

The proposed template systems can be further developed to be considered as infrastructure necessary for design within a collaborative engineering environment. Further research and development is necessary for implementation. Though, the result from this case is promising.

The paper proposes the structure necessary for the implementation of a template‐based system. The approach used in the development of the integrated systems could be used by small and mid segment industries which do not have enough resources for costly software upgrading and complex computer technologies. By using templates, the time required for new product development is drastically reduced.

Computer aided design systems are routinely used by designers for creating part geometries. Interfaces to computer aided analysis and manufacturing are also commonplace enabling the rapid fabrication of the designed part. Thus far, however, the focus was on objects with homogeneous interior. Two recent advances use of functionally graded materials in parts, and layered manufacturing technology have brought to the forefront the need for CAD systems to support the creation of geometry as well as the graded material inside. This paper reports on such a system. We describe the need, the components and implementation of a CAD system for creating heterogeneous objects. Two examples illustrate the use.

Given the importance of information technology in today′s society an understanding of the process by which technologies are diffused within and between societies is clearly important. Presents a model of this diffusion process which has been developed on the basis of an extensive research programme looking at the diffusion of production and inventory control systems within the components sector of British industry. This model suggests attention needs to be paid to three factors – the technological innovation itself, the vendors/suppliers of the innovation, and the user organization. Highlights the practical utility of this approach.