A. Caignot, P. Ladevèze, D. Néron and J.‐F. Durand
The purpose of this paper is to propose a virtual testing strategy in order to predict damping due to the joints which are present in the ARIANE 5 launcher.
Abstract
Purpose
The purpose of this paper is to propose a virtual testing strategy in order to predict damping due to the joints which are present in the ARIANE 5 launcher.
Design/methodology/approach
Since engineering finite element codes do not give satisfactory results, either because they are too slow or because they cannot calculate dissipation accurately, a new computational tool is introduced based on the LArge Time INcrement (LATIN) method in its multiscale version.
Findings
The capabilities of the new strategy are illustrated on one of the joints of ARIANE 5. The damping predicted virtually is compared to experimental results, and the approach appears promising.
Originality/value
The tool which has been developed gives access to calculations which were previously unaffordable with standard computational codes, which may improve the design process of launchers. The code is transferred into ASTRIUM‐ST, where it is being used to build a database of dissipations in the joints of the ARIANE 5 launcher.
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Francisco Chinesta, Adrien Leygue, Marianne Beringhier, Linh Tuan Nguyen, Jean‐Claude Grandidier, Bernhard Schrefler and Francisco Pesavento
The purpose of this paper is to solve non‐linear parametric thermal models defined in degenerated geometries, such as plate and shell geometries.
Abstract
Purpose
The purpose of this paper is to solve non‐linear parametric thermal models defined in degenerated geometries, such as plate and shell geometries.
Design/methodology/approach
The work presented in this paper is based in a combination of the proper generalized decomposition (PGD) that proceeds to a separated representation of the involved fields and advanced non‐linear solvers. A particular emphasis is put on the asymptotic numerical method.
Findings
The authors demonstrate that this approach is valid for computing the solution of challenging thermal models and parametric models.
Originality/value
This is the first time that PGD is combined with advanced non‐linear solvers in the context of non‐linear transient parametric thermal models.
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Zimou Tang, Min Yang, Jianxiong Xiao, Zheng Shen, Liming Tang and Jibin Wang
This paper aims to present an engineering computational method for fatigue life evaluation of welded structures on large-scale equipment under random vibration load.
Abstract
Purpose
This paper aims to present an engineering computational method for fatigue life evaluation of welded structures on large-scale equipment under random vibration load.
Design/methodology/approach
Based on a case study of the traction transformers, virtual fatigue test (VFT) was proposed via numerical simulation approach. Static analysis was conducted to identify the risky zone and then dynamic response of the risky welds under random vibration load was calculated based on frequency-domain structural stress method (FDSSM) theory, life distribution and associated survivability at various locations of the structure were obtained. Structural modification was finally performed according to the evaluation results. Moreover, experimental test was carried out and compared with the virtual test result.
Findings
By applying the virtual test, fatigue life of the complex welded structures on large-scale equipment can be accurately and efficiently obtained considering dynamic effect under random vibration load. Meanwhile, risky welds can be directly determined and targeted modification scheme can be accordingly concluded. Validity of the VFT result was proved by comparing with the experimental test.
Originality/value
The proposed method can help obtain equivalent structural stress and fatigue life distribution of the welded structure at any position with various survivability and make quantitative evaluation on the life-extending effect of the structural modification. This method shows significant cost and efficiency advantages over experimental test during design stage of the large-scale structures in numerous manufacturing industries.
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Qian Li, Qinshan Sun, Sha Tao and Xinglin Gao
Recently, there has been increasing focus on the development of multi-skilled workforce in project management. The purpose of this paper is to investigate a multi-skill project…
Abstract
Purpose
Recently, there has been increasing focus on the development of multi-skilled workforce in project management. The purpose of this paper is to investigate a multi-skill project scheduling problem (MSPSP), which combines project scheduling and multi-skill personnel assignment. The distinct features of skill evolution and cooperation effectiveness are considered in the problem to maximize the total project effectiveness and skill development simultaneously.
Design/methodology/approach
The Bi-objective non-linear integer programming (LIP) models are formulated for the problem using three types of skill development objective function: number of experts, total skill increment and “bottleneck” skill increment. Non-linear models are then linearized through several linearization techniques, and the ε-constraint method is used to convert the bi-objective models into single-objective models.
Findings
A construction project case is used to validate the proposed models. In comparison with models that do not consider skill evolution and cooperation effectiveness, the models proposed in this paper offer more realistic solutions and show better performance with regard to both project effectiveness and skill development.
Originality/value
This research extends the current MSPSP by considering skill evolution based on the “learning effect” as well as the influence of cooperation in an activity-based team, which are common phenomena in practice but seldom studied. LIP models formulated in this paper can be solved by any off-the-shelf optimization solver, such as CPLEX. Besides, the proposed LIP models can offer better project scheduling and personnel assignment plan, which would be of immense practical value in project management applications.
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This chapter focuses on the normative importance of what attitudes our actions express to others. Business is not conducted in a vacuum – rather, it is conducted against a…
Abstract
This chapter focuses on the normative importance of what attitudes our actions express to others. Business is not conducted in a vacuum – rather, it is conducted against a background schema of social meaning. This chapter argues that the public meaning of our actions, what our actions express, is normatively important. The piece imports familiar norms regarding expressions from interpersonal morality to business ethics, such as those surrounding insult, blame, and gratitude. It argues that many of ethicists’ gripes across a range of business ethics topics – from disproportionate compensation to immoral investing – can fruitfully be analyzed from an expressive perspective.
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Yifei Ren and Zhiqiang Lu
In response to the station design and flexible resources allocation of the aircraft moving assembly line, a new problem named flexible resource investment problem based on project…
Abstract
Purpose
In response to the station design and flexible resources allocation of the aircraft moving assembly line, a new problem named flexible resource investment problem based on project splitting (FRIP_PS), which minimizes total cost of resources with a given deadline are proposed in this paper.
Design/methodology/approach
First, a corresponding mathematical model considering project splitting is constructed, which needs to be simultaneously determined together with job scheduling to acquire the optimized project scheduling scheme and resource configurations. Then, an integrated nested optimization algorithm including project splitting policy and job scheduling policy is designed in this paper. In the first stage of the algorithm, a heuristic algorithm designed to get the project splitting scheme and then in the second stage a genetic algorithm with local prospective scheduling strategy is adopted to solve the flexible resource investment problem.
Findings
The heuristic algorithm of project splitting gets better project splitting results through the job shift selection strategy and meanwhile guides the algorithm of the second stage. Furthermore, the genetic algorithm solves resources allocation and job schedule through evaluation rules which can effectively solve the delayed execution of jobs because of improper allocation of flexible resources.
Originality/value
This paper represents a new extension of the resource investment problem based on aircraft moving assembly line. An effective integrated nested optimization algorithm is proposed to specify station splitting scheme, job scheduling scheme and resources allocation in the assembly lines, which is significant for practical engineering applications.
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The Equator Principles are a transnational corporate social responsibility initiative in the project finance sector. In 2013, the Equator Principles Association celebrated the…
Abstract
The Equator Principles are a transnational corporate social responsibility initiative in the project finance sector. In 2013, the Equator Principles Association celebrated the tenth anniversary of its principles and at the same time the formal launch of the latest generation of the Equator Principles (EP III). The paper describes the historic development of the Equator Principles – from the initial drafting process in the early 2000s up to the latest review process which led to the third generation of the Equator Principles. The paper also analyzes the current state of affairs of the Equator Principles (Association) and gives a brief outlook on potential lines of (future) development. In particular, the paper deals with the following questions: What are the main characteristics of the Equator Principles framework? What are the relevant actors involved in the drafting and reviewing process? Why are the EPs and other organizational and associational codes of conduct in the finance sector so important? What has been achieved so far by the Equator Principles (Association) and the participating (financial) institutions and what remains to be done?
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Dheeraj Joshi, M.L. Mittal, Milind Kumar Sharma and Manish Kumar
The purpose of this paper is to consider one of the recent and practical extensions of the resource-constrained project scheduling problem (RCPSP) termed as the multi-skill…
Abstract
Purpose
The purpose of this paper is to consider one of the recent and practical extensions of the resource-constrained project scheduling problem (RCPSP) termed as the multi-skill resource-constrained project scheduling problem (MSRCPSP) for investigation. The objective is the minimization of the makespan or total project duration.
Design/methodology/approach
To solve this complex problem, the authors propose a teaching–learning-based optimization (TLBO) algorithm in which self-study and examination have been used as additional features to enhance its exploration and exploitation capabilities. An activity list-based encoding scheme has been modified to include the resource assignment information because of the multi-skill nature of the algorithm. In addition, a genetic algorithm (GA) is also developed in this work for the purpose of comparisons. The computational experiments are performed on 216 test instances with varying complexity and characteristics generated for the purpose.
Findings
The results obtained after computations show that the TLBO has performed significantly better than GA in terms of average percentage deviation from the critical path-based lower bound for different combinations of three parameters, namely, skill factor, network complexity and modified resource strength.
Research limitations/implications
The modified TLBO proposed in this paper can be conveniently applied to any product or service organization wherein human resources are involved in executing project activities.
Practical implications
The developed model can suitably handle resource allocation problems faced in real-life large-sized projects usually administered in software development companies, consultancy firms, R&D-based organizations, maintenance firms, big construction houses, etc. wherein human resources are involved.
Originality/value
The current work aims to propose an effective metaheuristic for a more realistic version of MSRCPSP, in which resource requirements of activities may be more than one. Moreover, to enhance the exploration and exploitation capabilities of the original TLBO, the authors use two additional concepts, namely, self-study and examination in the search process.
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Purpose: This chapter examines how two basic rights, freedom of expression, and the right to equality based on one’s dignity, reputation, and honor, were balanced in a case…
Abstract
Purpose: This chapter examines how two basic rights, freedom of expression, and the right to equality based on one’s dignity, reputation, and honor, were balanced in a case involving a stand-up comedian and an adolescent suffering from Treacher Collins syndrome. Methodology/Approach: The case is contrasted with Jürgen Habermas’ concept of the public sphere and with the intrinsic and utilitarian values that Canadian courts have attributed to free speech. Findings: Because the case was dealt with first in a human rights tribunal and then by a court of appeal, a number of considerations were overlooked in court proceedings: how laughter occurs; the broadening of Ward’s audience and its consequences; and Ward’s publicity strategy. These aspects are explored here to give a more complete picture of the case beyond the court decisions. Originality/Value: In Canada, freedom of expression is usually dealt with ordinary courts. A whole new avenue for dealing with this right is human rights bodies and tribunals. Contesting free speech in the name of defamation is being replaced by rights entrenched in human rights charters, such as the right to equality based on the preservation of one’s dignity, reputation, and honor.
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Amir Hossein Hosseinian, Vahid Baradaran and Mahdi Bashiri
The purpose of this paper is to propose a new mixed-integer formulation for the time-dependent multi-skilled resource-constrained project scheduling problem (MSRCPSP/t…
Abstract
Purpose
The purpose of this paper is to propose a new mixed-integer formulation for the time-dependent multi-skilled resource-constrained project scheduling problem (MSRCPSP/t) considering learning effect. The proposed model extends the basic form of the MSRCPSP by three concepts: workforces have different efficiencies, it is possible for workforces to improve their efficiencies by learning from more efficient workers and the availability of workforces and resource requests of activities are time-dependent. To spread dexterity from more efficient workforces to others, this study has integrated the concept of diffusion maximization in social networks into the proposed model. In this respect, the diffusion of dexterity is formulated based on the linear threshold model for a network of workforces who share common skills. The proposed model is bi-objective, aiming to minimize make-span and total costs of project, simultaneously.
Design/methodology/approach
The MSRCPSP is an non-deterministic polynomial-time hard (NP-hard) problem in the strong sense. Therefore, an improved version of the non-dominated sorting genetic algorithm II (IM-NSGA-II) is developed to optimize the make-span and total costs of project, concurrently. For the proposed algorithm, this paper has designed new genetic operators that help to spread dexterity among workforces. To validate the solutions obtained by the IM-NSGA-II, four other evolutionary algorithms – the classical NSGA-II, non-dominated ranked genetic algorithm, Pareto envelope-based selection algorithm II and strength Pareto evolutionary algorithm II – are used. All algorithms are calibrated via the Taguchi method.
Findings
Comprehensive numerical tests are conducted to evaluate the performance of the IM-NSGA-II in comparison with the other four methods in terms of convergence, diversity and computational time. The computational results reveal that the IM-NSGA-II outperforms the other methods in terms of most of the metrics. Besides, a sensitivity analysis is implemented to investigate the impact of learning on objective function values. The outputs show the significant impact of learning on objective function values.
Practical implications
The proposed model and algorithm can be used for scheduling activities of small- and large-size real-world projects.
Originality/value
Based on the previous studies reviewed in this paper, one of the research gaps is the MSRCPSP with time-dependent resource capacities and requests. Therefore, this paper proposes a multi-objective model for the MSRCPSP with time-dependent resource profiles. Besides, the evaluation of learning effect on efficiency of workforces has not been studied sufficiently in the literature. In this study, the effect of learning on efficiency of workforces has been considered. In the scarce number of proposed models with learning effect, the researchers have assumed that the efficiency of workforces increases as they spend more time on performing a skill. To the best of the authors’ knowledge, the effect of learning from more efficient co-workers has not been studied in the literature of the RCPSP. Therefore, in this research, the effect of learning from more efficient co-workers has been investigated. In addition, a modified version of the NSGA-II algorithm is developed to solve the model.