Improving the performances of part dispatching based on multiple process plans using graph theory

An intrinsic characteristic for manufacturing a part is the existence of diverse processing routes. In this paper, we deal with the improvement of part dispatching performance based on the availability of multiple process plans of a machined part. Procedures to represent multiple process plans with a graphic representation are developed so as to facilitate the utilization of process plans. We propose a simulation model to test the impacts of multiple process plans on the performances of real time scheduling. The study shows that by applying the simulation model to multiple processes in the manufacturing of machined parts, the flexibility of the manufacturing system can be increased; the total production flow time can be reduced; and the efficient utilization of production resources is improved.     

Structural equation modeling of sustainable manufacturing practices

The purpose of this research study is to study the sustainable manufacturing practices across industrial sectors and to identify the critical factors for its success implementation. In spite of the fact that sustainable manufacturing has been frequently promoted as a means of improving business competitiveness, small empirical evidence exists in the literature validating its positive link with organizational performance. Sustainable manufacturing practices enable the manufacturing organizations to survive in the competitive environment. For this purpose, empirical data are collected to measure the sustainable manufacturing practices prevailing across different industries located in Tamil Nadu, India. Structural equation modeling (SEM) technique is used to build the measurement and structural models. After that, statistical estimates are used to validate the built model. The data analysis enables the acceptance or rejection of the hypothesis that has been stated on the basis of structural model. The results show the correlation between sustainable manufacturing practices and organizational performance among the industries being surveyed.     

Hybrid systems for planning and optimization of virtual assembly

Virtual assembly is the simulation of parts assembly processes by computer, analysing, evaluating and optimizing the feasibilities and procedures of assembly. It can thus avoid the potential problems and risks from designing to assembling. In this way, we can achieve the global optimization of the products and timely respond to the needs of the market. This paper presents a modelling framework for virtual assembly paths design and optimization of two objects on the basis of a class of hybrid system, which is applicable in many manufacturing environments. We propose an elementary hybrid machine containing time-driven and event-driven dynamics. We describe in detail a method of assembly paths design. The objective of optimization is evaluated in terms of time in the transition dynamics so as to make the problem more tractable. An explicit algorithm for deriving optimal assembly policies is developed. The optimal results indicate the feasibility and efficacy of the model and control algorithms.     

Combining MPC and integer operators for capacity adjustment in job-shop systems with RMTs

With today's worldwide competition, manufacturing companies are faced with challenges to respond to volatile market demands quickly and flexibly while maintaining a cost-effective level of production. Capacity adjustment is one of the major approaches to cope with such uncertain fluctuations, balance capacity and load and improve the effectiveness of manufacturing control. Instead of flexible staffs, working time and outsourcing, in this paper, we consider a machinery-based capacity adjustment via Reconfigurable Machine Tools (RMTs) to compensate for unpredictable events. To include these tools effectively on the operational and tactical layer, we propose a complementing feedback approach using model predictive control (MPC) to identify the potential of RMTs for a better compliance with logistics objectives and a sustainable demand oriented capacity allocation. To this end, we formulate a reconfiguration rule for the determination of the triggered RMTs and propose three strategies for resolving the integer assignment of RMTs: floor operator, genetic algorithm as well as branch and bound. Utilising simulation, we demonstrate the effectiveness of the proposed method for a four-workstation job-shop system.     

A process systems framework for rapid generation of life cycle inventories for pollution control and sustainability evaluation

Life cycle assessment (LCA) is a tool that aids in sustainable decision-making among product and process alternatives. When implementing LCA, the efficient and accurate modeling of chemical processes for life cycle inventory (LCI) generation is still challenging. Challenges include a lack of systematic design and simulation tools and approaches to develop chemical process models for obtaining and analyzing more realistic LCI results. In this contribution, a novel process systems framework is proposed for estimating LCI results when implementing pollution control technologies. This framework involves the development and incorporation of pollution control unit (PCU) modules into process simulation and generation of LCI data associated with the PCUs for use in a sustainability evaluation. Different pollution control modules are designed for rapid LCI estimation and applied to obtain emissions, utility consumption, material, and land footprint results related to waste streams of a process simulation. Then, the LCI results are analyzed with the objectives of minimizing the environmental impact and utility consumption. The proposed framework is illustrated via a biomass/coal gasification process for syngas production with the end goal of acetic acid manufacturing. Results associated with this case study show that the developed framework can provide guidelines for sustainable decision-making based on generated LCI results.     

Application of interpretive structural modelling for analysing the factors influencing integrated lean sustainable system

The modern manufacturing systems recognize the importance of adopting lean and sustainable manufacturing principles. Especially, Indian automotive component manufacturing organizations are interested in adopting the integrated lean sustainable manufacturing system. An appropriate methodology is required for enabling the organizations to identify the dominant factors. In this context, this article presents the interpretive structural modelling approach for identifying the mutual relationship among factors influencing the integrated lean sustainable manufacturing system. From the literature study and survey conducted among Indian automotive component manufacturing organizations, 25 influencing factors have been identified. Based on the study, top-management commitment in adopting integrated lean sustainable manufacturing and environmental knowledge occupy the bottom level of model which shows that it has more driving power. Efforts are being taken to implement the factors in the surveyed organizations.     

Manufacturing knowledge management strategy

The study sought to understand the components of knowledge management strategy from the perspective of staff in UK manufacturing organizations. To analyse this topic, we took an empirical approach and collaborated with two manufacturing organizations. Our main finding centres on the key components of a knowledge management strategy, and the relationships between it and manufacturing strategy and corporate strategy. Other findings include: the nature of knowledge in manufacturing organizations; the relevance of (in)formal processes; top-down and bottom-up communication; taking ownership for information processes. We also make comments on the development of action plans for better knowledge management. The implications are that, for an integrated approach to knowledge management strategy in manufacturing organizations, involvement across the organization and at all levels is necessary.     

Design and analysis of computer experiment via dimensional analysis

Design and analysis techniques for computer experiments have been largely developed. However, empirical emulators generated based on experimental data usually fail to incorporate physical principles and dimensional constraints the computer model follows. In this article, we propose a new design and analysis framework based on dimensional analysis (DA), a widely used reduction technique in physics and engineering. We show that implementing DA in computer experiments is efficient, scalable, interpretable, robust and costless. We demonstrate the benefits and improvement in details by theoretical derivations and numerical examples of the borehole model and the damped harmonic oscillation.     

The significance of organizational change management for sustainable competitiveness in manufacturing: exploring the firm archetypes

The successful development and deployment of adequate sustainable manufacturing strategies are still open issues and of utmost interest for research and practice. Guided by this particular challenge, we investigate the significance of organisational change management for sustainable competitiveness in manufacturing. By using six case studies from the Lombardia region in Italy and basing our research on the theoretical constructs of competitive aggressiveness and organisational change, we discover four archetypes of companies that show an increasing sustainable competitiveness with an increasing formalism and persistence in organisational change. Our findings suggest that change management practices are conditional hypothesis for creating competitive advantage through sustainability, and implementation gaps do hinder companies in realising the full potential. The study offers guidance to stakeholders, on how change management actions may potentially affect company performance in the manufacturing sector, as well as providing direction on the impact improved planning and leadership instances can have on the sustainability performance.     

Simulation optimisation of pull control policies for serial manufacturing lines and assembly manufacturing systems using genetic algorithms

Several efficient pull production control policies for serial lines implementing the lean/JIT manufacturing philosophy can be found in the production management literature. A recent development that is less well-studied than the serial line case is the application of pull-type policies to assembly systems where manufacturing operations take place both sequentially and in parallel. Systems of this type contain assembly stations where two or more parts from lower hierarchical manufacturing stations merge in order to produce a single part of the subsequent stage. In this paper we extend the application of the Base Stock, Kanban, CONWIP, CONWIP/Kanban Hybrid and Extended Kanban production control policies to assembly systems that produce final products of a single type. Discrete-event simulation is utilised in order to evaluate the performance of serial lines and assembly systems. It is essential to determine the best control parameters for each policy when operating in the same environment. The approach that we propose and probe for the problem of control parameter selection is that of a genetic algorithm with resampling, a technique used for the optimisation of stochastic objective functions. Finally, we report our findings from numerical experiments conducted for two serial line simulation scenarios and two assembly system simulation scenarios.     

A method of seamlessly combining a crack tip molecular dynamics enclave with a linear elastic outer domain in simulating elastic–plastic crack advance

Molecular dynamics is applicable only to an extremely small region of simulation. In order to simulate a large region, it is necessary to combine molecular dynamics with continuum mechanics. Therefore, we propose a new model where molecular dynamics is combined with micromechanics. In this model, we apply molecular dynamics to the crack tip region and apply micromechanics to the surrounding region. Serious problems exist at the boundary between the two regions. In this study, we manage to solve these problems, and make possible the simulation of the process of crack propagation at the atomic level. In order to examine the validity of this model, we use α-iron for simulation. If the present model is valid, stress and displacement should vary continuously across the boundary between the molecular dynamics region and the micromechanics region. Our model exhibits just such behavior. This revised version was published online in August 2006 with corrections to the Cover Date.     

A new game of information sharing and security investment between two allied firms

In consideration of business information sharing, this paper investigates a new game of information sharing and security investment between two allied firms. Firms’ strategies in three decision models (Nash Equilibrium decision, partially centralised decision and totally centralised decision) are analysed. We provide some quantitative analyses on how some parameters affect firms’ decisions in the three decision models. Our Nash Equilibrium analysis shows that when firms make decisions individually, they will share no information with each other. When information sharing is determined by a social planner, firms will share some information with each other, which increases the risk of information leakage. Thus, firms should increase their security investments to mitigate the higher information leakage risk. However, our analysis shows that instead of investing more in information security, firms will reduce their security investment, which will further aggravate the risk. Hence, a social planner is required to designate the security investments and information sharing levels for both firms. Our theoretical analysis shows that firms’ strategies can achieve global optimality in the totally centralised decision model. Furthermore, a numerical experiment is conducted and the result demonstrates that totally centralised decision model is more efficient than the other two decision models. At last, we propose two compensation mechanisms to help firms coordinate their strategies when making decisions individually.     

计算机仿真在生产系统分析中的应用

系统总结了计算机仿真技术对生产系统的重要作用,利用Ithink5．0软件建立了简单生产过程的计算机仿真模型并进行了分析。     

Towards a holistic sustainability index for measuring sustainability of manufacturing companies

Competition from low wage countries and the adoption of free market strategies have forced manufacturing firms to recognise and implement productivity enhancement strategies. This research defines a holistic sustainability index embedding several performance indices. The aim of this study was to establish a relevant framework that would assess the current situation of an industry through aggregation of environmental, social, economical as well as manufacturing variables. The proposition has its roots in trends and gaps in the sustainability literature of manufacturing industries and is based on the analytic hierarchy process (AHP) method. A list of indicators measuring the industry performance based on an AHP scoring methodology is proposed. The next stages include grouping industries according to common deficiencies across the four dimensions and establishing a cooperation framework. The food manufacturing industry is the main target in this study and will benefit from adopting sustainable long-term policies. By recognising the importance of social–environmental sustainability and taking the initiative to pursue it, profits will grow as a positive effect of such policies. The added value is twofold: (1) coupling all sustainability dimensions, often addressed in silos and (2) integrating manufacturing indicators which enable the analysis of interrelationships with sustainability.     

Responsible intellectual property strategy for sustainability transition - An exploratory study

In this paper, we propose a responsible intellectual property (IP) strategy (R-IPS) framework based on five exploratory case studies of sustainable companies in energy, nutrition, consumer electronics, manufacturing and water treatment sectors. These companies responsibly use IP assets to create positive social and environmental impact (or reduce negative impact), and unlock new opportunities for financial (economic) gains. The extent to which firms today use IP rights such as patents and trademarks, and IP more broadly (including informal intellectual assets such as data and trade secrets, and contracts) as a strategic tool to facilitate sustainability remains to be understood better. More specifically, we need understanding of how companies could, or even should manage and use their IP more responsibly in these changing times during which transitions towards sustainable development are so thoroughly and urgently needed. The proposed framework defined using five dimensions namey deliberation/intention, sustainability IP alignment, flexibility and timing, inclusiveness, and co-creation can support managerial decision-making in formulating or re-designing IP strategies to increase organization's social and environmental impact, maximising their contributions (e.g. accelerating transitions) towards building sustainable economies.     

Sustainability characterisation for manufacturing processes

Manufacturing industries lack the measurement science and the needed information base to measure and effectively compare environmental performances of manufacturing processes, across resources and associated services with respect to sustainability. The current use of ad hoc methods and tools to assess and describe sustainability of manufactured products does not necessarily account for manufacturing processes explicitly, and hence results in inaccurate and ambiguous comparisons. Such comparisons do not proactively contribute to sustainability improvement. Further, we identified that there are no formal methods for acquiring and exchanging information that help establish a consolidated sustainability information base. Our ultimate goal is to develop the needed measurement science and methodology to evaluate sustainability of fundamental manufacturing processes to ensure reliable and consistent comparisons. As a precursor, based on a literature study, this paper identifies the required elements to evaluate sustainability performance for manufacturing with a focus on the environmental impact. Societal and economic impacts, although equally important, are beyond the scope of discussion in this paper. In this paper, we first discuss identified manufacturing process classifications, sustainable manufacturing indicators and computable metrics, relevant information models and software tools, a conceptual model for sustainability characterisation, and finally, conclude with an overview of the future research directions.     

Innovation Strategies: Are Knowledge-Intensive Business Services Just Another Source of Information?

The objective of this paper is to contribute to the empirical literature on innovation strategies and services, by analysing the use of knowledge-intensive services, and their impact on innovation, in manufacturing firms. The analysis is carried out at the firm level, on the basis of a survey covering 804 manufacturing establishments in the Province of Quebec (Canada). We investigate the extent to which existing internal capabilities and their interaction with external sources of knowledge, in particular the use of knowledge-intensive business services (KIBS), affect the level of innovativeness of manufacturing firms. Then we examine the extent to which different innovation strategies, and the way KIBS are integrated into these, are associated with innovation. We show that manufacturing firms adopt a variety of innovation strategies, none of which preclude innovation, even introverted strategies whereby firms interact little with outside agents. However, those strategies that incorporate KIBS have a considerably greater chance of leading to innovation.     

Approaching lean product development using system dynamics:investigating front-load effects

Competing with successful products has become perplexing with several uncertainties and transmutes from time to time as customers’ expectations are
dynamic. That is why manufacturing firms exhaustively strive to look for a better competitive frontier using wellestablished and innovative product development (PD) processes. In this paper, we would like to answer three research questions: (i) What would be the effects of frontloading
in PD? (ii) Can we improve our PD process endlessly? (iii) When is the critical time that the firm should take remedial action for improvements? As a contribution to the vast numbers of improvement methods in new product development (NPD), this paper investigates the effects of front-loading using set-based concurrent engineering (SBCE) on cost and lead time. Models are developed and treated using a system dynamics (SD) approach. We assign a hypothetical upfront investment for SBCE and compare its effects on  total cost and lead time of the development process. From the research, it is found that the total cost of PD is reduced almost by half-although the front loading is higher in order to encompass multiple design alternatives. The total product lead time is reduced by almost 20 %. The model reveals the critical time for improvement of the PD process. We use SD tool (e.g., STELLA) for simulation and visualization of the complex PD model, using SBCE as one of several strategies to frontload activities in the NPD process.     

Who Follows Whom? A Location Study of Chinese Private and State-Owned Companies in the European Union

This paper analyses the location decision of Chinese manufacturing firms for their greenfield investments in Europe. The analysis draws on neo-institutional theory to formulate hypotheses on the importance of mimicry in Chinese firms’ location decisions and how this differs between private and state-owned enterprises. The analysis is conducted at the subnational (regional) level while taking into account economic integration across regions. The results confirm the importance of mimicry and show that Chinese firms not only follow previous Chinese investors in the same sector but also in unrelated sectors. Furthermore, Chinese investors only follow previous investments by Chinese private-owned companies while the results also show that Chinese private-owned companies generally have a higher tendency than state-owned companies do to follow prior investment decisions by compatriot firms. As the empirical evidence demonstrates the importance of bandwagon effects, the implication is that investment decisions can have a lasting influence on the geographical pattern of Chinese investments across regions.     

Product and employee development in advanced manufacturing: Implementation and impact

As competitive intensity increases and the need for rapid, responsive and efficient production rises, manufacturers need to develop effective strategies that lever all a firm's resources into a competitive weapon. One challenge managers face in today's dynamic global economy is to choose appropriate manufacturing practices and then to integrate them into a cohesive value-added strategy that will yield enhanced competitive performance. The sheer number and range of manufacturing 'strategies' that have emerged over the past 20 years exacerbate the challenge. The goal of this study is therefore to look at four highly publicized manufacturing strategies and then examine their interrelationships and impact on firm performance: (1) integrated product development, (2) employee development, (3) just-in-time manufacturing and (4) manufacturing automation. The responses of 158 managers from randomly selected US manufacturing firms were used to develop a covariance matrix to facilitate the use of a structural equations model via LISREL. The analysis indicates that employee and product development strategies are important antecedents of just-in-time and automation strategies. All four advanced manufacturing practices have significant, positive impacts on organizational competitiveness.