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The purpose of this research paper is to discuss cellular manufacturing is discussed under conditions of changing product demand. Traditional cell formation procedures ignore any changes in demand over time from product redesign and other factors. However given that in today's business environment, product life cycles are short, a framework is proposed that creates a multi‐period cellular layout plan including cell redesign where appropriate.

The framework is illustrated using a two‐stage procedure based on the generalized machine assignment problem and dynamic programming. This framework is conceptually compared to virtual cell manufacturing, which is useful when there is uncertainty in demand rather than anticipated changes in demand. A case study is used to explain how the concept would work in practice.

One major characteristic of the proposed method is that it is flexible enough to incorporate existing cell formation procedures. It is shown through an example problem that the proposed two‐stage method is better than undergoing ad hoc layout changes or ignoring the demand changes when shifting or cell rearrangement costs exist. It also sheds some insight into cellular manufacturing under dynamic conditions.

This paper should be useful to both researchers and practitioners who deal with demand changes in cellular manufacturing.

The purpose of this paper is to optimize a new thin-walled cellular configurations with crashworthiness criteria, so as to improve the crashworthiness of components of a vehicle body.

ANSYS Parametric Design Language is used to create the parameterized models so that the design variables can be changed conveniently. Moreover, the surrogate technique, namely response surface method, is adopted for fitting objective and constraint functions. The factorial design and D-optimal criterion are employed to screen active parameters for constructing the response functions of the specific energy absorption and the peak crushing force. Finally, sequential quadratic programming-NLPQL is utilized to solve the design optimization problem of the new cellular configurations filled with multi-cell circular tubes under the axial crushing loading.

Two kinds of distribution modes of the cellular configurations are first investigated, which are in an orthogonal way and in a diamond fashion. After comparing the optimized configurations of the rectangular distribution with the annular distribution of the multi-cell fillers, it is found that the orthogonal way seems better in the aspects of crashworthiness than the diamond fashion.

The two new thin-walled cellular configuration are studied and optimized with the crashworthiness criteria. Study on the new cellular configurations is very valuable for improving the crashworthiness of components of a vehicle body. Meanwhile, the factorial design and the factor screening are adopted in the process of the crashworthiness optimization of the new thin-walled cellular configurations.

Over the last ten years scores of methodologies have emerged in management science/operations research/statistics that employ techniques such as mathematical programming, simulation, artificial intelligence, and clustering to convert a flexible manufacturing system into a cellular one. Based on a real‐life case that involved over 1,000 components and 3,000 operations, related to a world‐class furniture manufacturing company, finds that the somewhat outdated King’s algorithm, after partial linearization, works as well as the other sophisticated techniques in terms of speed and problem size. Drives home the point that a shift to cellular configuration from functional layout results in across the board savings in material movement, setup times, hilo moves, WIP, work area and in manufacturing leadtime. The company under study benefited to the tune of $164,000 per year from switch to single cell. The projected savings are expected to exceed $700,000 per year when the reconfiguration is completed.

Despite increasing public attention and media coverage of the Covid-19 pandemic, little research was conducted on how the crisis affected accountability practices in the not-for-profit sector. This study focusses on international non-governmental organisations (INGOs) that operate in emerging economies worldwide but are registered in England and Wales and examines how their online accountability practices changed after the Covid-19 pandemic. The purpose of this paper is to address these issues.

The authors use the theoretical lens of the situational crisis communication theory (SCCT) and a contingency approach to not-for-profit governance in order to assess how accountability practices have been shaped by the response given by INGOs to preserve their reputation which is argued to be damaged by the COVID-19 pandemic. They use Dumont's (2013) nonprofit virtual accountability index (NPVAI) for statistical analysis. They examine whether the five dimensions of the NPVAI have changed significantly as a policy of response to the Covid-19 pandemic. They also examine the documents used to disclose information on performance, governance and mission to understand if their content was affected by the pandemic.

The authors found two of the NPVAI dimensions: accessibility and engagement to be statistically different compared to before the pandemic. They also examined the documents used to disclose information on performance, governance and mission in order to understand if their content were affected by the pandemic. Their findings suggest that INGOs focussed on keeping their donors' attention and their fund flow rather than informing how they performed and how their governance has changed as a result of the pandemic. No statistically significant change was found regarding the dimensions of performance, governance and mission.

INGOs which focus on humanitarian relief and crises management mainly in emerging economies were also affected by the pandemic. However little attention has been given to how accountability was being shaped by the Covid-19 pandemic. An analysis of how not-for-profit sector accountability practices were affected by the pandemic is, therefore, needed. Due to the nature of the pandemic online accountability practices is an area where research could focus on, until now few studies have been conducted on online accountability. The study contributes methodologically by assessing the applicability of the NPVAI for comparisons across different time periods rather than across different types of organisation at a specific point in time. The authors conclude that the NPVAI must be supplemented by some analysis of the content of key online documents and other material.

The authors’ findings provide important implications for crisis management and its effect on accountability practices in INGOs that operate in emerging economies and the not-for-profit sector in general. The findings suggest that the crisis led to only limited changes in mission and governance as changes in these dimensions tend to occur over the long term. Although they expected the pandemic to lead to more performance information being released, this did not happen. The enhancement of online accountability practice in the engagement and accessibility dimensions shows that INGOs focussed more on maintaining their fund flow rather than on actions to target the pandemic. This is especially apparent as regardless of size the donation and fundraising links have increased throughout the pandemic. Overall, the study provides important findings specific to the effects of the Covid-19 pandemic on online accountability practices in the not-for-profit sector. The study's empirical contribution is to assess how not-for-profit organisations shape their online accountability practices to preserve their reputation and legitimacy.

The authors have expanded the discussion of the paper's contribution to theory, methodology and knowledge about online accountability and crisis management in the conclusion section of the paper. They found that INGOs have reacted to the pandemic by becoming more anxious about their ability to generate funds, and content analysis showed that there was little additional information about how INGOs' performance had been affected by the pandemic, which suggests that INGOs need to pay more attention to how they manage accountability in times of crisis.

The authors construct a conceptual framework using theories that have the potential to explain how external factors such as the Covid-19 pandemic can affect online accountability practices. Their paper also responds to the call for studies of the effectiveness of various accountability mechanisms in NGOs (Unerman and O’ Dwyer, 2006). Unlike previous studies they did not compare various sectors at a single point in time, but rather they assessed the impact of the Covid-19 pandemic and the reaction of INGOs by comparing online disclosures across time. This is a novel use of Dumont's NPVAI and therefore provides an important contribution to the literature.

To program cellular automata is to define cell neighbourhood and cell‐state transition rules in order to design an automation which exhibits determined patterns in its evolution or which transforms a given image into another image. In general, a tool for the automatic programming of cellular automata should translate the tuple (source‐configuration) → (target‐configuration) into a set of cell‐state transition rules. This is a problem which has not been completely solved yet. Attempts to show examples of automatic programming of cellular automata using identification algorithms. Results obtained can be used in the design of massively parallel processors with cellular‐automata architecture and a conventional, as well as non‐traditional (e.g. molecular and chemical), elementary base.

Proposes a virtual cellular manufacturing approach to implementing cellular manufacturing systems that combines the set‐up efficiency typically obtained by traditional cellular manufacturing or group technology systems with the flexibility of a job shop. Unlike traditional cellular systems in which the shop is physically designed as a series of cells, cells are formed within a shop utilizing a process layout using scheduling mechanisms. The result is the formation of cells that are temporary and logical (virtual) in nature, allowing them to be more responsive to changes in demand patterns. Simulation runs comparing this approach to production using traditional cellular and job shop approaches indicate that this new approach yields significantly better shop performance over a range of operating conditions.

The design of a cellular manufacturing system requires that a machine population be partitioned into machine groups called manufacturing cells. A new graph partitioning heuristic is proposed to solve the manufacturing cell formation problem (MCFP). In the proposed heuristic, The MCFP is represented by a graph whose node set represents the machine cluster and edge set represents the machine‐pair association weights. A graph partitioning approach is used to form the manufacturing cells. This approach offers improved design flexibility by allowing a variety of design parameters to be controlled during cell formation. The effectiveness of the heuristic is demonstrated by comparing it to two MCFP published solution methods using several problems from the literature.

This study aims to analyse slender thin-walled anisotropic box-beams. Fiber-reinforced laminated composites could play an important role in the design of current and future generations of innovative civil aircrafts and unconventional unmanned configurations. The tailoring characteristics of these composites not only improve the structural performance, and thus reduce the structural weight, but also allow possible material couplings to be made. Static and dynamic aeroelastic stability can be altered by these couplings. It is, therefore, necessary to use an accurate and computationally efficient beam model during the preliminary design phase.

A proper structural beam scheme, which is a modification of a previous first-level approximation scheme, has been adopted. The effect of local laminate stiffness has been investigated to check the possibility of extending the analytical approximation to different structural configurations. The equivalent stiffness has been evaluated for both the case of an isotropic configuration and for simple thin-walled laminated or stiffened sections by introducing classical thin-walled assumptions and the classical beam theory for an equivalent system. Coupling effects have also been included. The equivalent analytical and finite element beam behaviour has been determined and compared to validate the considered analytical stiffness relations that are useful in the preliminary design phase.

The work has analyzed different configurations and highlighted the effect of flexural/torsion couplings and a local stiffness effect on the global behaviour of the structure. Three types of configurations have been considered, namely, a composite wing box configuration, with and without coupling effects; a wing box configuration with sandwich and cellular constructions; and a wing box with stiffened panels in a coupled or an uncoupled configuration. An advanced aluminium experimental test sample has also been described in detail. Good agreement has been found between the theoretical and numerical analyses and the experimental tests, thus confirming the validity of the analytical relations.

The equivalent beam behaviour that has been determined and the stiffness calculation procedure that has been derived could be useful for future dynamic and aeroelastic analyses.

The article presents an original derivation of the sectional characteristics of a thin-walled composite beam and a numerical/experimental validation.

The purpose of this paper is to present an application of cellular manufacturing techniques and the evaluation of alternative production scenarios.

Advanced techniques were implemented in the production process of a company and then the efficiency of the effected changes on its operation were evaluated. Group technology was adopted as the (re)organization tool of its production. Indices concerning the performance of the system were identified using “real world” production results and statistical data. The operational characteristics of 12 alternative production scenarios were evaluated using the cellular manufacturing approach. The behavior of the manufacturing system as a whole, for each one of the different scenarios, was investigated using the discrete events simulation technique for a period of two years. Finally, data envelopment analysis was employed to evaluate the efficiency of each scenario.

Results indicated that more than one of these scenarios could be efficient, while significant improvements can be achieved without actually changing the basic production parameters.

The proposed procedure was implemented in a company from the cosmetics industry.

The paper presents a successful application of cellular manufacturing techniques together with the evaluation of alternative production scenarios.

This research provides a new perspective on the long-standing debate of open-plan versus cellular offices. It analyzes the effects of workplace layouts on organizational outputs such as innovation, efficiency and privacy by considering the physical space of an organization alongside its organizational structure. This socio-spatial approach draws on correspondence theory originating from space syntax to understand the potential for unplanned encounters between diverse groups of people.

Three different organizations are studied, two open-plan and one cellular office. Floor and seating plans are analyzed to calculate the degree of correspondence between the spatial and conceptual closeness of people. Demands for each organization are derived from semi-structured interviews and publicly available information.

The three studied organizations present very different degrees of openness toward others in ways that challenge conventional views of cellular and open-plan offices. In each case, the degree of correspondence matches the demands placed on the organization, and hence, providing a relatively good fit between the organization and interior environment.

A larger sample of open-plan and cellular offices would be useful to consider in further research.

Managers can use the concept of correspondence to generate the appropriate degree of unplanned encounters between the right sets of people in order to achieve the best organization-environment fit.

The main innovation of this paper lies in its socio-spatial approach, considering physical space alongside managerial, organizational choices.