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Just‐in‐time (JIT) systems were originally designed for deterministic production environments such as constant processing times and smooth and stable demand. However, once implemented, JIT is fraught with numerous types of uncertainties, including variations in processing time and demand, planned interruptions such as preventive maintenance and unplanned interruptions such as equipment failure. These uncertainties lead to lowered production throughput, decreased machine utilization, increased order completion time and greater backlogs and overtime requirements. In this paper, we introduce a newly developed system, which we refer to as the flexible kanban system (FKS), to cope with uncertainties and planned/unplanned interruptions. We demonstrate the superiority of the new system by considering four case examples covering various uncertainties, conducting numerous studies and comparing the overall performances of the FKS with that of the traditional JIT system. In all the cases considered, the performance of the FKS was, indeed, superior to that of the traditional JIT system.

To study the breakdown (MI) mechanism in the sub‐micron MOSFET device.

Second‐order Poisson's differential equation is solved for suitable boundary condition to find the electric field expression for the sub‐micron devices. With the help of the electric field expression the exact relation for multiplication factor is derived, and then the equation for breakdown voltage has been generated.

This research paper provides the following findings: by controlling oxide thickness, junction depth and drain voltage, the breakdown can be easily controlled in the sub‐micron device; multiplication factor is not only affected by maximum field but also due to critical field; for very low gate voltage, the offset voltage mainly governs the breakdown; the breakdown voltage increases continuously as the channel length increases. It means, for larger channel length the breakdown will occur at high drain voltage.

This paper is based on the assumption that the electric field along the channel is independent of the junction depth (although not correct) and varying linearly from zero to E_sat.

The paper derived the exact expression of the multiplication factor. Also discusses that for MI mode of breakdown, the breakdown voltage increases slowly with the gate voltage and approximated by drain saturation voltage plus offset voltage.

The electrochemical behaviour of zinc in different concentrations of Na₂SO₄ (pH = 6.0) was investigated using the potentiodynamic anodic polarization single sweep and cyclic voltammogram techniques. The anodic portion is characterized by one distinct peak corresponding to Zn(OH)₂ or ZnO. This is followed by a passive region up to a certain potential; the passive current suddenly rises steeply without any sign of oxygen evolution. This denotes the breakdown of the passive film and initiation of pitting corrosion. It was found that the breakdown potential depends on the sulphate concentration, type of aeration, scan rate, solution temperature and pH. The pitting initiation may be explained through the adsorption of SO₄^2– anion on the oxide film formed. This decreases the repair efficiency and causes further metal dissolution. From the cyclic voltammogram of zinc in different concentrations of Na₂SO₄, it was found that the change in the integrated anodic charge, Δq_a, which is taken as a measure of the extent of pitting, varies linearly with concentration of SO₄^2– anion.

Purpose – The aim of this paper is to analyze the changes that took place in occupational segregation by gender, nationality, and age in Switzerland during the period 1970–2000.

Methodology – The paper starts by using correspondence analysis to detect changes in occupational segregation by gender and nationality. It then generalizes a decomposition procedure originally proposed by Karmel and McLachlan by combining their approach with what is now known as the Shapley decomposition. Such a generalization offers a clear breakdown of the variation over time in occupational segregation into a component measuring changes in net segregation and another one corresponding to changes in the margins, the latter itself including variations in the occupational structure and in the shares of the subpopulations (e.g., the genders) in the labor force.

Findings – Between 1970 and 2000 there was a slight increase in gross segregation by gender but a decrease in net segregation. The change in gross segregation is because the change in the margins more than compensated that in the internal structure. But even the change in the margins is the consequence of opposite forces since variations in the occupational structure would have per se led to a decrease in gross segregation.

Originality – The results of the empirical illustration based on Swiss data for 1970 and 2000 prove the usefulness of the approach. They stress in particular that in several instances, variations in gross and net segregation worked in opposite directions.

The purpose of this paper is to study a production lot sizing problem with consideration of imperfect manufacturing and emergency maintenance policy, providing managerial implication for practitioners.

In this study, the authors introduce two models, where in Model I, shortages are not allowed and repair times are negligible. In Model II, shortages are allowed and are partially backlogged, and repair times are assumed to be exponentially distributed, algorithm is developed to solve the models, numerical examples were demonstrated the applications.

Results show that in the Model I, demand rate is the most significant parameter affecting the average expected cost, whereas the time needed to breakdown after machine shift is the most significant factor affecting the production lot size. Therefore, reduction in the time needed to breakdown after machine shift would be helpful for determining an appropriate production lot size in Model I. In Model II, repair time parameter is the most significant factor affecting the average expected cost. Reducing the value of machine shift parameter would be helpful for determining an adequate production lot size and reducing decision risk.

This paper can provide important reference value for practitioners with managerial implication of how to effectively maintain equipment, i.e. how to make product lot size considering the influence of the maintenance policy.

From the aspect of academia, this paper provides a solution to the optimal production lot sizing decision for an imperfect manufacturing system with consideration of machine breakdown and emergency maintenance, which is a supplement to imperfect EMQ model.

This paper proposes a knowledge management approach for managing uncertainty in manufacturing enterprises.

The knowledge management approach consists of a knowledge‐enriched manufacturing system, which is modelled using SIMAN simulation language and programmed using Visual Basic applications. A knowledge‐based planning module and an execution platform are simulated so that signals could be transferred, and configuration to the planned parameters could be made, in order to minimise variations due to uncertainties. A reference architecture and intelligent agent are created to store tacit knowledge and create explicit knowledge, respectively.

Manufacturing enterprises should use both tacit knowledge about uncertainties and buffering and dampening techniques, simultaneously with the explicit knowledge that is generated by the intelligent agent, for managing uncertainty. The design of the knowledge management approach enables easy integration with material requirements planning, manufacturing resource planning or enterprise resource planning systems, and complements with the adoption of advanced technology.

A new concept – management by valued‐added urgency, emerges that underpins the knowledge management approach. It is grounded from the previous literature on managing uncertainty classified into: masking approach; standardising approach; prioritising approach; and optimising approach and extended Westbrook's priority management theory. This concept focuses selectively on value‐added changes that need to be made to counteract variations caused by significant uncertainty.

The purpose of this paper is threefold: identifying the root causes and other causal factors of terrorism, exploring the recent shifts in terrorist activity, and proposing a context-centred framework for deterring terrorism risk.

The first part of this research is based on extensive up-to-date observations made by the author and extracted from real-life settings and social interactions. The second part is based on a survey questionnaire reflecting public views on terrorism and related issues.

The risk of terrorism risk is increasingly becoming a major concern of all societies including Jordanian. The results have shown that terrorism is context related and that there are several and different root causes for this phenomenon. Many other causal factors have the potential to increase the impact or probability of terrorism risk in Jordan. The existing framework(s) for deterring terrorism risk in Jordan is not adequate and need to be reformed extensively.

This study provides insight to the root causes of the potential terrorist activity in Jordan, as well as other causal factors. It is expected to establish a foundation for policy-makers and decision-makers to start considering the causes of social unrest and subsequently develop appropriate frameworks for mitigating terrorism risk.

This study is made in a time of unprecedented political instability and terrorist activity in the Middle East and the Arab World. It reflects genuine observations and public opinions, thus providing authentic findings and better understanding of the concerns of the society. Most importantly, the study proposes context-related framework for counteracting terrorism activity and future evolution of this phenomenon in the Middle East, in general, and Jordan, in particular.

Industrialized construction (IC) has been recognized as a game-changing approach in Hong Kong (HK). However, the increasing risks of disruptions in IC supply chains (SCs) raise SC vulnerability levels, prompting attention to developing supply chain resilience (SCR). Since SCR is only attainable through overcoming critical supply chain vulnerabilities (CSCV) with enhanced SC capabilities, this study first aimed to determine the most CSCV of ICSCs by addressing this current research gap and practical need.

Drawing on SCV factors identified from a precursor literature review, an empirical study of IC in HK was conducted using a questionnaire survey and interviews with industry experts. Focussed significance analysis of the data collected through questionnaire survey enabled the selection of 26 CSCV as appropriate to IC. Next, factor analysis was conducted, enabling the grouping of these CSCV under five components. The results were verified and reinforced by interview findings.

The results revealed 26 CSCV pertinent to resilient ICSCs in HK with five underlying components: economic, technological, procedural, organizational and production-based vulnerabilities. Loss of skilled labour is the most critical vulnerability, whereas organizational SCV is the most critical component identified.

Findings of this study would motivate IC project professionals to appreciate and address the CSCV in the context of five components and thereby develop adequate specific capabilities to successfully withstand these CSCV. This should trigger future studies to map CSCV with appropriate capabilities in developing an envisaged powerful assessment model for evaluating the SCR in IC in HK.

Describes a computer simulation technique which has been applied to model an automotive manufacturing system in order to predict the system performance under an increasing demand. Using Sim View, a locally developed, graphically animated simulation package, the electro‐phoretic deposition plant was modelled and sensitivity analysis was carried out. Confirms some of the problems that were thought may arise, and highlights some other issues that may become problematic. Aims to produce possible suggestions for avoiding problems and improving the performance of the system. Plans further uses of the simulation model in studies to gain greater efficiency in the system and possibly to experiment with any future upgrades that may be considered.

This paper aims to deal with the experimental estimation of both longitudinal- and lateral-directional aerodynamic characteristics of a new twin-engine, 11-seat commuter aircraft.

Wind tunnel tests have been conducted on a 1:8.75 scaled model. A modular model (fuselage, wing, nacelle, winglet and tail planes) has been built to analyze both complete aircraft aerodynamic characteristics and mutual effects among components. The model has been also equipped with trailing edge flaps, elevator and rudder control surfaces.

Longitudinal tests have shown the goodness of the aircraft design in terms of aircraft stability, control and trim capabilities at typical clean, take-off and landing conditions. The effects of fuselage, nacelles and winglets on lift, pitching moment and drag coefficients have been investigated. Lateral-directional stability and control characteristics of the complete aircraft and several aircraft component combinations have been tested to estimate the aircraft components’ interactions.

The experimental tests have been performed at a Reynolds number of about 0.6e6, whereas the free-flight Reynolds number range should be between 4.5e6 and 9.5e6. Thus, all the measured data suffer from the Reynolds number scaling effect.

The study provides useful aerodynamic database for P2012 Traveller commuter aircraft.

The paper deals with the experimental investigation of a new general aviation 11-seat commuter aircraft being brought to market by Tecnam Aircraft Industries and it brings some material on applied industrial design in the open literature.