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The purpose of this paper is to review, evaluate and classify the academic research that has been published in facility layout problems (FLPs) and to analyse how researches and practices on FLPs are.

The review is based on 166 papers published from 1953 to 2021 in international peer-reviewed journals. The literature review on FLPs is presented under broader headings of discrete space and continuous space FLPs. The important formulations of FLPs under static and dynamic environments represented in the discrete and continuous space are presented. The articles reported in the literature on various representations of facilities for the continuous space Unequal Area Facility Layout Problems (UA-FLPs) are summarized. Discussed and commented on adaptive and robust approaches for dynamic environment FLPs. Highlighted the application of meta-heuristic solution methods for FLPs of a larger size.

It is found that most of the earlier research adopted the discrete space for the formulation of FLPs. This type of space representation for FLPs mostly assumes an equal area for all facilities. UA-FLPs represented in discrete space yield irregular shape facilities. It is also observed that the recent works consider the UA-FLPs in continuous space. The solution of continuous space UA-FLPs is more accurate and realistic. Some of the recent works on UA-FLPs consider the flexible bay structure (FBS) due to its advantages over the other representations. FBS helps the proper design of aisle structure in the detailed layout plan. Further, the recent articles reported in the literature consider the dynamic environment for both equal and unequal area FLPs to cope with the changing market environment. It is also found that FLPs are Non-deterministic Polynomial-complete problems, and hence, they set the challenges to researchers to develop efficient meta-heuristic methods to solve the bigger size FLPs in a reasonable time.

Due to the extremely large number of papers on FLPs, a few papers may have inadvertently been missed. The facility layout design research domain is extremely vast which covers other areas such as cellular layouts, pick and drop points and aisle structure design. This research review on FLPs did not consider the papers published on cellular layouts, pick and drop points and aisle structure design. Despite the possibility of not being all-inclusive, the authors firmly believe that most of the papers published on FLPs are covered and the general picture presented on various approaches and parameters of FLPs in this paper are precise and trustworthy.

To the best of the authors’ knowledge, this paper reviews and classifies the literature on FLPs for the first time under the broader headings of discrete space and continuous space representations. Many important formulations of FLPs under static and dynamic environments represented in the discrete and continuous space are presented. This paper also provides the observations from the literature review and identifies the prospective future directions.

This paper aims to propose a space-oriented solution as an interface enabling the knowledge transfer between the building and the facilities management (FM) industry.

The research gap is explored based on practical investigations in six large-scale hospitals in China. The theory of engineering systems integration inspires the proposed solution. A practical scenario is demonstrated to explain the workflow of this solution.

It is founded that lagging information updates of FM systems in hospital project are one of the main reasons for inefficient and costly FM workflow. Building information modelling (BIM) model could provide accurate building information to the FM systems at the building handover stage. However, few researchers focus on the continuous information transfer solution from the BIM model to FM systems during the building in-use phase. An interface should be established for the “conversation” between the frequent changes of building and the FM systems in the post-construction period.

The information updates in three FM systems due to space changes in a hospital project is considered as a practical scenario in this paper. It is presented with the workflow and the data logic chain.

The originality of this paper is to propose a solution to integrate the space information provided by the BIM model with the parameters of particular FM systems. This solution deploys a BIM model for the FM industry. The solution could allow the FM personnel to ease operations and maintenance workflow by updating the space information in the BIM model.

In an attempt to solve multiobjective optimization problems, many traditional methods scalarize an objective vector into a single objective by a weight vector. In these cases, the obtained solution is highly sensitive to the weight vector used in the scalarization process and demands a user to have knowledge about the underlying problem. Moreover, in solving multiobjective problems, designers may be interested in a set of Pareto‐optimal points, instead of a single point. In this paper, Pareto‐based Continuous Evolutionary Algorithms for Multiobjective Optimization problems having continuous search space are introduced. These algorithms are based on Continuous Evolutionary Algorithms, which were developed by the authors to solve single‐objective optimization problems with a continuous function and continuous search space efficiently. For multiobjective optimization, a progressive reproduction operator and a niche‐formation method for fitness sharing and a storing process for elitism are implemented in the algorithm. The operator and the niche formulation allow the solution set to be distributed widely over the Pareto‐optimal tradeoff surface. Finally, the validity of this method has been demonstrated through some numerical examples.

Problem specification is a key front-end step in the innovation process. This paper aims to introduce ‘purpose-context’ – a conceptual framework to systematically explore problem-specification across mapped contexts. The framework’s logic is operationalized by the inherent structure of language – its syntax/grammar, which enables the systematic exploration of problem-specification. The method showcases two approaches to structurally explore the vast textual databases available to us today for problem-specification in innovation science, thereby furthering the pursuit of innovation through its foundational elements.

The conceptualization of the purpose-context framework was guided by logic and the scholarship of integration applied to bodies of work including innovation, design and linguistics. Further, the key elements of the conceptual framework were unpacked and structured using the syntax of language. Two approaches to operationalize the method were developed to illustrate the systematicity of the process. The construct was then validated by using it to systematically specify problems in the technical context of Raman spectroscopy and in the socio-technical context of international development. Overall, this paper is a work of relational scholarship of integration that bridges academic-practitioner gaps.

The purpose-context framework is well-suited for application in the innovation process with applicability across several abstraction levels. One key contribution is the recognition that a broader problem-specification exercise covering one-one, one-many, many-one, many-many problem-context mappings expands the range of potential solutions (innovations) to address the problem-space. Additionally, the work finds that it is possible to provide structure to the cognitive elements of the innovation process by drawing inspiration from the structure inherent in other cognitive processes such as language (e.g., parts-of-speech, phrase composition). Drawing from language is particularly appropriate as language mediates communication in any collective pursuit of the innovation process and furthermore because a large amount of information exists in textual form. Finally, this paper finds that there is merit in approaching innovation science from its foundational elements – i.e. data, information and knowledge.

While the purpose-context framework is broadly applicable, the methodical approach to provide structure to the front-end cognitive process is ‘one’ fruitful approach. We suspect other approaches exist.

The purpose-context framework is simple in its framing yet provides innovators, scholars and thought leaders, the ability to specify the problem space with greater coverage and precision. Further, in the solution-space, it provides them the ability to choose the breadth of solution scope (e.g. targeted solution addressing a single problem, targeted solution addressing a set of problems, the combination of solutions addressing a single problem and combination of solutions addressing a combination of problems). In addition, by pairing the creative front-end innovation process with machine power, this study provides a formal method to scale-up the coverage of creativity (and potentially that of solutions to those problems) and reduces the chances of missed/blind-spots in problem-specification. Finally, evaluating purpose-contexts leads to ‘capability-contexts’ – a capability-oriented viewpoint informing capability development decisions such as the focus of R&D programs and related resource allocation decisions.

The paper uses logic to connect multiple bodies of research with a goal to provide systematicity to problem-specification – problem-specification, which is an under-addressed part of the innovation process. The use of data to systematically explore problem-space lends it systematicity (repeatability and measurability) and is therefore, valuable to innovation science. The proof-of-concept demonstrates the conversion of concept into a method for practical application.

The extensive applications of the industrial robots have made the optimization of assembly lines more complicated. The purpose of this paper is to develop a balancing method of both workstation time and station area to improve the efficiency and productivity of the robotic assembly lines. A tradeoff was made between two conflicting objective functions, minimizing the number of workstations and minimizing the area of each workstation.

This research proposes an optimal method for balancing robotic assembly lines with space consideration and reducing robot changeover and area for tools and fixtures to further minimize assembly line area and cycle time. Due to the NP-hard nature of the considered problem, an improved multi-objective immune clonal selection algorithm is proposed to solve this constrained multi-objective optimization problem, and a special coding scheme is designed for the problem. To enhance the performance of the algorithm, several strategies including elite strategy and global search are introduced.

A set of instances of different problem scales are optimized and the results are compared with two other high-performing multi-objective algorithms to evaluate the efficiency and superiority of the proposed algorithm. It is found that the proposed method can efficiently solve the real-world size case of time and space robotic assembly line balancing problems.

For the first time in the robotic assembly line balancing problems, an assignment-based tool area and a sequence-based changeover time are took into consideration. Furthermore, a mathematical model with bi-objective functions of minimizing the number of workstations and area of each station was developed. To solve the proposed problem, an improved multi-objective immune clonal selection algorithm was proposed and a special coding scheme is designed.

Recently, many-objective optimization evolutionary algorithms have been the main issue for researchers in the multi-objective optimization community. To deal with many-objective problems (typically for four or more objectives) some modern frameworks are proposed which have the potential of achieving the finest non-dominated solutions in many-objective spaces. The effectiveness of these algorithms deteriorates greatly as the problem’s dimension increases. Diversity reduction in the objective space is the main reason of this phenomenon.

To properly deal with this undesirable situation, this work introduces an indicator-based evolutionary framework that can preserve the population diversity by producing a set of discriminated solutions in high-dimensional objective space. This work attempts to diversify the objective space by proposing a fitness function capable of discriminating the chromosomes in high-dimensional space. The numerical results prove the potential of the proposed method, which had superior performance in most of test problems in comparison with state-of-the-art algorithms.

The achieved numerical results empirically prove the superiority of the proposed method to state-of-the-art counterparts in the most test problems of a known artificial benchmark.

This paper provides a new interpretation and important insights into the many-objective optimization realm by emphasizing on preserving the population diversity.

The purpose of this paper is to investigate the feasibility of solving an integrated flight scheduling, fleet assignment and crew pairing problem for an on-demand service using a small, up to 19-seater, aircraft.

Evolutionary algorithm is developed to solve the problem. Algorithm design assumes indirect solution representation that allows to evaluate partially feasible solutions only and speed up calculations. Tested algorithm implementation takes advantage of the graphic processing unit.

Performed tests confirm that the algorithm can successfully solve the defined integrated scheduling problem.

The presented algorithm allows to optimise on-demand transport service operation within minutes.

Optimisation of operation cost contributes to better accessibility of transport.

The presented integrated formulation allows to avoid sub optimal solutions that are results of solving sequential sub problems. Indirect representation and evaluation strategy can be applied to speed up calculations in other problems as well.

Nowadays many parameter studies for the design and optimization of electromagnetic devices are carried out by means of 2D and 3D nonlinear finite element (FE) models. Through optimization algorithms selecting one design as optimal with respect to the chosen cost function, the user does not gain any intuitive clue of the interrelations existing between design parameters, although numerous computations have been performed across the whole parameter space of the system. The purpose of this paper is to visualize a complex nonlinear FE solution system, which is parameterized through a number of control variables, in virtual reality (VR).

This paper presents a visualization approach for n‐dimensional parameter spaces of FE solutions in VR and the corresponding interpolation methods for enabling navigation through it.

The solution of an arbitrary electromagnetic FE problem is categorized with respect to possible changes, due to chosen design parameters, within the solution itself and variations in the underlying mesh in order to find appropriate interpolation methods for the visualization of each type of parameter space.

The implementation is based on modifying the popular Visualization Toolkit (VTK).

The paper presents different solution approaches for the visualization of an interpolation between arbitrary different meshes, but the problem remains unsolved and requires further research.

The purpose of this paper is to examine what organisational and management practices used in connection with open space flexible offices create business value. It seeks to identify what consequences this may have for successful real estate practices.

This paper utilises an inductive case study approach. The international telecom company Telenor has implemented open space flexible offices from top to bottom amongst their 35,000 employees. The case description and analysis is based on secondary data, user evaluations and 20 interviews with middle- and top-level managers across levels and functional departments.

The case of Telenor reveals that leadership and organizing issues are important, together with work modes and communication technology, for a productive use of work place design. The paper highlights specifically how the open, transparent, flexible office solution creates business value when used with centralised and standardised organisational management systems and a participative, informal leadership culture.

The study is based on one case, so the findings need to be tested across a representative sample of companies.

Managers need to take both organisational and management issues into consideration when implementing new office space design. This challenges also the existing real estate strategies to include the organisational and management issues in their planning.

The originality and value of the paper lies in the analysis and findings of the Telenor case introducing organizational and management perspectives to real estate issues.