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This paper aims to better design the resonant tank parameters for LLC resonant converter. And, it is found that under heavy load, the voltage gain is affected by junction capacitors of the primary side switching and the parasitic parameters of the secondary side diodes converted to the primary side, which will cause the voltage gain decreased when the switching frequency decreased.

This paper proposes an optimization parameters design method to solve this problem, which was based on impedance model considering the parasitic parameters of switching devices and diodes.

The effectiveness of the proposed method is verified by impedance Bode plots and experimental results.

From the perspective of impedance modeling, this paper finds the reasons for the insufficient voltage regulation capability of LLC resonant converters under heavy load and finds solutions through analysis.

Reviews the individual experiences of many small southeastern US firms as they attempted to meet the challenge of overseas markets, sometimes in response to market saturation at home or to smooth out the seasonality of product demand. Although many small firms were initially reluctant to “go global”, those who did so found that they were able to work through the hurdles and build strong overseas markets. Reviews the variety of measures and techniques which individual firms used to turn obstacles into a successful global venture. Explores the most important lessons which these firms learned in the process.

Aims to examine the impact of health and safety legislation emanating from the European Community and to analyse what effect, if any, it will have on British occupational health and safety law. An examination of the social action programmes shows that the pace of change has increased rapidly since the Single European Act was incorporated into the Treaty of Rome and became operative from July 1987. Because of rapid changes that are occurring on a broad front there was a need to be selective. Emphasizes to some extent, therefore, the construction industry because it would appear that European legislation is likely to have a major impact on British law and practice in this industry.

Uninterruptible Power Supply (UPS) systems are typically designed to provide power to computers for five to thirty minutes after all utility company power has failed. In addition to providing blackout and brownout protection, many UPS systems also protect against spikes, surges, sags, and noise, and some also offer many of the features found in power distribution units (PDUs). The major components or subsystems of a typical UPS system are detailed, and a sample bid specification is appended. Three sidebars discuss UPSs and air conditioning, the maintenance bypass switch (MBS), and literature for further reading.

This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized innovative information technology open architecture design and integrating Radio Frequency Identification Device data technologies and real-time optimization and control mechanisms as the critical technology components of the solution. The innovative information technology, which pursues the focused logistics, will be deployed in 36 months at the estimated cost of $568 million in constant dollars. We estimate that the Systems, Applications, Products (SAP)-based enterprise integration solution that the Army currently pursues will cost another $1.5 billion through the year 2014; however, it is unlikely to deliver the intended technical capabilities.

Road trauma remains a significant concern internationally. Traffic crashes rank within the top three leading causes of death for individuals aged between 15–44 years old, with nonfatal casualties occurring at around 30 times the rate of fatal incidents. Historically, road safety research has not captured factors relating to driving purpose. However, more recently, researchers have focused on the importance of driving for work. Over a third of traffic volume represents commuting or driving in the line of employment; improving workplace road safety practices represents a tangible way of reducing road trauma. This chapter considers the link between safety culture and best practice in workplace road safety. It is argued that best practice is not a term to define individual safety practices, but a system of practices that create a culture of safety. This research uses data collected on organizations workplace road safety practices within the Australian context. This data has been collected by the National Road Safety Partnership Program (NRSPP); an initiative that constitutes a network of organizations and academics working together to develop a positive road safety culture. Twenty-four case studies are presented of organizations that have implemented workplace road safety programs to improve their safe driving culture. Qualitative analysis was conducted to systematically categorize the safety initiatives and their indicators of success. Almost all case studies expressed the importance of developing a safety-first culture in the workplace. Third-party regulation, internal policy and corporate social responsibility form the foundation of workplace safety. However, it was the culture and attitude towards the safety initiatives that achieved effectiveness in the long-term. The findings of this research support the argument that best practice is best achieved when integrated within a culture that values and prioritizes safety, rather than implemented in isolation to other elements in the workplace system.

IN this article it is proposed to deal with the broad principles of operation of the various systems of control of aircraft electrical generators which are in common use, rather than with the detail design features and the many minor variations adopted by different manufacturers of this type of equipment.

The purpose of this paper is to examine the necessity of longer and/heavier and/or faster freight train operations and their viability in the European context.

Using a case study, the current research applies qualitative methods, including desktop research and informal discussion with the rail freight industry and shippers. The case study is the recently conducted trial of 1.5 km long Marathon freight train in Europe.

The research finds that at this stage there is no commercial necessity of running a 1.5 km long train. There are technical and operational limitations which are less problematic, but the commercial necessity is a must and that will need sufficient traffic volume on a longer route (to justify extra time and cost incurred in marshalling yard and reasonable pre- and post-consolidated rail transport haul). The time required to form up/disperse such large formation could arguably be a major constraint for the train itself as well as for other services run on the same network. The authors agree in principle with the “do more with less” notion and the necessity of faster train concept. Also, the authors are agreeing with the heavier train aspect.

Considering the current and future (more semi-finished and finished, containerised) cargo trend, it is more important that freight train is operated consistently, reliably, and commercially attractive relatively faster and frequent serving moderate distances (around 300+ km). Towards this, the operation of merging two (or more) short trains to form up to 750 m long trains should be explored, in particular on the nine Rail Freight Corridors, to identify the potential and realistic opportunities for commercial deployment of “longer and/or faster and/or and heavier” freight train.

At the moment there is no need of a 1.5 km long freight train to improve the performance of EU railways.

The case study provides an important platform for debate on the contemporary notion of “longer”, “faster” and “heavier” freight trains in the European context.