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The virtual design environment offers users an opportunity to interact with a virtual prototyping rather than physical models and to build a fixture configuration in a realistic way. But the virtual reality (VR) environment tends to be inaccurate because humans have difficulty in performing precise positioning tasks. Therefore, it is necessary to implement precise object manipulation methods for assembly and disassembly activities, so that users can perform modular fixture configuration design efficiently in VE. The purpose of this paper is to develop a VR‐based modular fixture assembly design system, which supports the design and assembly of modular fixture configuration in a virtual environment.

Geometric constraint‐based method is utilized to represent and treat the assembly relationship between modular fixture elements. The paper presents a hybrid method of rule‐based reasoning and fuzzy comprehensive judgment to capture the user's operation intent and recognize geometric constraint. Through degrees of freedom based analysis, a mathematical matrix is presented for representing and reducing allowable motion of fixture elements, and a constraint‐based motion navigation approach is proposed to ensure that the manipulation of a fixture component not violate that the existing constraints.

The paper finds that the proposed techniques are applicable to the convenient manipulation and accurate positioning of fixture elements in a virtual environment.

Component manipulation plays a key role in interactive virtual assembly design. The proposed approach in this paper enables interactive assembly design of modular fixture in virtual environment.

This paper presents a geometric constraint‐based approach that realizes automatic assembly relationship recognition, constraint solving and motion navigation for interactive modular fixture assembly design in a virtual environment.

Since its inception, cost accounting has provided data to managers for the development of internal organizational performance measures. In the mid 1980s, Dr Eli Goldratt introduced a new management philosophy called the theory of constraints (TOC). This philosophy contained a new set of performance measures which linked together the strategic objectives and operational capabilities of the organization. This linkage allows for the maximization of profits. Since its introduction, there has been a growing amount of evidence documenting TOC’s ability to more tightly link local decisions to organizational performance than those of traditional cost accounting. This research used a simple Gedunken experiment to evaluate the difference between strategy driven product‐mix decisions based on TOC accounting and traditional cost accounting. In all cases, the constraint‐based approach to costing outperformed the traditional approach based on cost accounting.

Since the 1980s, firms have searched for better ways to align their cost management systems with the realities of their business environments. The advent of accelerated global competitiveness, reduced product life cycles, rapid technological advancements, and inter‐organizational supply chains have drastically increased the need for more effective approaches to cost management. In recent years, activity‐based, constraint‐based, and hybrid cost management systems have been adopted by some firms to dampen the effects of their traditional (full‐absorption) costing methodologies. However, a holistic approach is needed to facilitate strategic cost management based upon organizational objectives, organizational needs and capabilities, and customer requirements. The Theory of Constraints provides the foundation for developing cost management systems that are global, integrative, and strategic in nature. A framework is presented in this paper for using a constraint‐based approach to strategic cost management.

Supply chain collaboration amongst independent firms often provides larger benefits from effectively satisfying end customer needs than working in isolation. However, a lack of awareness about the existence of constraints along the supply chain prevents the benefits of collaboration from being fully realised. This paper attempts to apply the theory of constraints approach to overcome difficulties in realising the potential benefits of supply chain collaboration. Specifically, it shows how the theory of constraints approach can be used to expose an inherent dilemma of collaboration and establish collaborative replenishment policy and collaborative performance metrics so that the chain members can work together to advance supply chain profitability. Several opportunities for future research are recommended.

This paper aims to investigate the thermal performance of equivalent square and circular thermal systems and compare the heat transport and irreversibility of magnetohydrodynamic (MHD) nanofluid flow within these systems.

The research uses a constraint-based approach to analyze the impact of geometric shapes on heat transfer and irreversibility. Two equivalent systems, a square cavity and a circular cavity, are examined, considering identical heating/cooling lengths and fluid flow volume. The analysis includes parameters such as magnetic field strength, nanoparticle concentration and accompanying irreversibility.

This study reveals that circular geometry outperforms square geometry in terms of heat flow, fluid flow and heat transfer. The equivalent circular thermal system is more efficient, with heat transfer enhancements of approximately 17.7%. The corresponding irreversibility production rate is also higher, which is up to 17.6%. The total irreversibility production increases with Ra and decreases with a rise in Ha. However, the effect of magnetic field orientation (γ) on total EG is minor.

Further research can explore additional geometric shapes, orientations and boundary conditions to expand the understanding of thermal performance in different configurations. Experimental validation can also complement the numerical analysis presented in this study.

This research introduces a constraint-based approach for evaluating heat transport and irreversibility in MHD nanofluid flow within square and circular thermal systems. The comparison of equivalent geometries and the consideration of constraint-based analysis contribute to the originality and value of this work. The findings provide insights for designing optimal thermal systems and advancing MHD nanofluid flow control mechanisms, offering potential for improved efficiency in various applications.

Product configurator is a sales and production‐planning tool that helps to transform customer requirements into bills‐of‐materials, lists of features and cost estimations. The purpose of this paper is to introduce a method of how to analyse sales configuration models by using a design structure matrix (DSM) tool. By applying the DSM techniques, the sales configuration managers may sequence the product configuration questions and organize the connection to production.

First, the paper explains a sales configuration system structure from published academic and non‐academic works. These sources employ both theoretical and practical views on the topic of computer‐based sales expert systems. Second, the paper demonstrates an application of using DSM for configuration modelling.

The current sales configuration approaches include constraint‐based, rules‐based, and object‐oriented approaches. Product description methods vary, but the general problem remains the same: the configuration process should be designed in such a way that customer selections do not affect the previous selections. From the user point of view, answering the questions should be smooth and fast. In turn this will lead to the growing importance of building more effective product configuration models. DSM offers a systematic way to organise customer interface in sales configuration systems.

This paper analyses how DSM could help in planning product configuration modelling. Comparison of different sequences is presented. The examples used are hypothetical, but illustrate the suitability of DSM analysis. Companies are trying to establish easily configured product models, which are fast, flexible and cost‐effective for adjustments and modifications. Use of DSM may help in the roll‐out of sales configuration projects. DSM may also be used as a quick view to represent the complexity of product configurability. The future needs for configuration tools will be focused towards product model management from the technical limitations of different data storage approaches.

Configurator software creates product variants, which are logical descriptions of physical products. Variants have parameters which describe the customer‐made selections. The parameter selections may have interconnections between the choices. Some selections may affect further selections and some combinations may not be allowed for incompatibility, cost or safety reasons. There are several commercial software packages available for creating product configurations. Product description methods vary, but the general problem remains the same: the configuration process should be designed in such a way that customer selections do not affect the previous selections. Answering the questions should be smooth and fast. Configuration of complex products, for instance, airplanes, may include several sub‐systems and have various loops within the quotation process. The use of DSM may help in the roll‐out of sales configuration projects. DSM may also be used as a quick view to represent the complexity of product configurability.

The paper helps both researchers and practitioners to obtain a clearer view on the development of sales configuration systems and the potential of systematic DSM‐based product model analysis.

This study aims to analyse the business model of Jumia Travel, an innovative online travel agency (OTA) that operates in African markets. Focusing on market conditions and consumer behaviour in sub-Saharan Africa, where barriers to e-commerce are strong and tourism is viewed as a non-essential activity, the study examines the ways in which Jumia Travel carries out its development objectives in Côte d’Ivoire and revamps the OTA business model in relation to market constraints.

The study uses a descriptive-qualitative method based on desk research analysis of corporate sources, including websites, annual reports, public interviews of managers and newspaper articles. It also draws on primary sources collected through interviews with the Jumia Travel Côte d’Ivoire country manager.

The research shows that the demand- and supply-side constraints of African markets compel Jumia Travel to acquire new skills and competencies to adapt to and capture the Ivorian travel market. In doing so, the company expands the boundaries of the traditional OTA business models found in developed markets, demonstrating the dynamic capabilities that drive OTA business model transformation when deployed in a technologically immature market.

The Jumia Travel venture provides an insight into the constraints faced by an OTA at the bottom of the pyramid and in emerging markets and shows concretely what skills and competencies are required to overcome them. It is also a new experiment still in the early stages of development, and this limits the proper assessment of sustainability of its business model.

This study examines a unique experience: an unconventional OTA that concentrates exclusively on domestic and regional markets in sub-Saharan Africa. The business model lens brings into focus the operational limits and innovation opportunities of developing an e-travel business in the fast-growing markets of Africa, characterised by major supply-side constraints, the predominance of low-income consumers and a poorly structured travel industry. In this context, OTAs’ innovation challenge is no longer to disrupt the travel sector in differentiating from competitors, as was the case in the mature markets of the first world but to develop business processes suitable for operating in the constraint-based environment of emerging markets and capturing the rising demand for travel products. This involves co-creating value in linking African hotel providers and clients and increasing economic returns from this value through various business model adaptations designed for and with local consumers and partners.

Software agents are computer programs that run in the background and perform tasks autonomously as delegated by the user. Although there has been much research on this topic recently, usable software agents are at an early stage of development, and are only now starting to appear in real applications. Typical of these early stages, there has been a technology focus, rather than a product focus, in much of the development work to date. A fruitful application area for software agents is in the area of e‐commerce, where potential buyers can easily be overwhelmed by the flood of information that is available, thus potentially making less than optimal purchasing decisions. This paper blends models from marketing and learnings from the field of decision support systems to build a framework for the design of software agents to support in e‐commerce buying applications.

Green supply chain management and new product innovation and diffusion have become quite popular and act as a rich source of providing competitive advantage for companies to trade without further deteriorating environmental quality. However, research on low-carbon footprint supply chain configuration for a new product represents a comparably new trend and needs to be explored further. Using relatively simple models, the purpose of this paper is to demonstrate how carbon emissions concerns, such as carbon emission caps and carbon tax scheme, could be integrated into an operational decision, such as product procurement, production, storage and transportation concerning new fast-moving consumer goods (FMCG) product introduction.

The situation titled “low-carbon footprint supply chain configuration problems” is mathematically formulated as a multi-objective optimization problem under the dynamic and stochastic phenomenon concerning receiver’s demand requirements and production plant capacity constraints. Further, the effects of demand and capacities’ uncertainties are modeled using the chance constraint approach proposed by Charnes and Cooper (1959, 1963).

Various cases have been validated using the case example of a new FMCG product manufacturer. To validate the proposed models, data are generated randomly and solved using optimization software LINGO 10.0.

The attempt is novel in the context of considering the dynamic and stochastic phenomenon with respect to demand center’s requirements and manufacturing plant’s capacity constraints with regard to the low-carbon footprints supply chain configuration of a new FMCG product.

This paper is an attempt to understand how Amartya Sen's thinking on development and freedom has evolved from his critique of welfare economics and his concern with underdevelopment and poverty. It is argued that Sen has done a great deal to rescue welfare economics from the consequences of methodological individualism by seeking an objective basis for comparisons of well‐being, by insisting on the need for interpersonal comparability and by creating a space for normative evaluations. Sen's contribution to the human development approach with its emphasis on positive freedom has also helped to provide a valuable counterweight to the dominant free market approach. However, some concerns are expressed that the approach does not give sufficient attention to long‐run dynamics and that the conception of capability employed is not helpful for the understanding of development