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The increasing number of Plug-in Electric Vehicles (PEVs) impacts the power grid due to their high demand in power and energy, and uncertainties in the charging behavior. Typical PEVs are charged single-phase up to 32 A (7.2-kVA) or tri-phase up to 32 A (22.0- kVA). Both charging technologies have to be discussed in order to determine their impact on planning and operating of low-voltage distribution grids to assure a reliable and stable PEV charging. Traditional grid planning and analysis methods, which average and evenly distribute PEV loads on the distribution grid, fail in providing a realistic answer about the grid capacity to charge PEVs. The question; How many PEVs can be charged simultaneously on a distribution grid remains unanswered. Therefore, this paper describes a novel methodology to realistically evaluate the grid capacity for PEV charging on 3-phase 0.4-kV distribution grids.

The benefits of automated drafting (CAD) and manufacturing (CAM) are proven, and integration (CIM) will bring even greater productivity improvements. Mechanical engineers involved in concept design, however, have not yet benefited from automation; in fact, they are an island of non-automation. Now, powerful and affordable hardware, and advancements in solids modeling. analysis, and database software, are incorporated in sophisticated desktop computer systems for concept engineers. These systems automate the conceptualization, design, analysis, communications, and personal documentation functions. Automating the concept design stage of product development, thereby creating a new front end of CIM, will have an enormous positive impact on development cycles, product quality, and costs. This paper addresses two aspects of MCAE: the place of MCAE in the mechanical engineering environment, and MCAE system standards as identified by Fortune 500 engineers practicing in that environment.

The McDonnell Aircraft Company (MCAIR) [ILLEGIBLE]sign philosophy pertaining to the departure [ILLEGIBLE]d spin resistance and out-of-control recovery [ILLEGIBLE]aracteristics of fighter aircraft is pre[ILLEGIBLE]nted. The more important military specification requirements are reviewed and their [ILLEGIBLE]fluence on this philosophy is discussed. Aerodynamic stability and control criteria and control system design guidelines are presented which are used to assure that a fighter aircraft will exhibit a high level of departure and spin resistance and rapid recovery from out-of-control situations.

Currently, even the small diesel engines are required to reduce CO2 emissions toward carbon-neutral society. One of the methods to realize this would be to use alternative fuels. Therefore, this research focuses on a liquid which is called MCH (Methylcyclohexane), it is expected as one of the "hydrogen carriers" that can transport hydrogen from foreign country efficiently. MCH is produced overseas by adding hydrogen to the toluene, and the hydrogen is extracted after transport to the destination. However, there is significant energy loss in extracting hydrogen process from MCH [1]. Therefore, it would be more hydrogen efficient use through MCH as fuel for the small diesel engines directly, rather than for power generation by extracting hydrogen, since it does not have that significant energy loss of MCH blended fuel in this research.

Mechanical and structural systems often implement a structural integrity program to monitor and sustain structural reliability throughout the service life. To properly consider uncertainty and variability, one commonly used decision tool is probabilistic risk assessment that incorporates probabilistic damage accumulations, damage detections, mitigation actions, and expected costs of maintenance and failure consequences. Given the wide spectrum of maintenance options and the increasing complexities in high-fidelity modeling, the implementation of RBMO can be very challenging and, computationally, only random simulations can provide flexible and robust simulation capabilities.

In December 1981 the Maritime Communication Satellite MCS-A, was successfully launched on board ARIANE L04 to become the European Space Agency's first commercial telecommunication satellite. Presented in this paper is the history associated with the formulation, development and testing of the Thermal Control Subsystem designed for MCS-A, as well as a report from the initial evaluation of its in-orbit performance.

New materials are developed each year to address the ever increasing emphasis on Noise, Vibration, and Harshness (NVH) in automotive product development. One such innovative material, Micro-Cellular Urethane, rapidly approaching mainstream development activity, provides sound & vibration engineers an alternative to the standard butyl and natural rubber compounds typically implemented in vehicle isolation strategies. MCU offers a number of characteristics which are advantageous in addressing vehicle NVH issues. This paper explains the design process involved in optimizing MCU as a material choice in body mount applications.

Today, co-operative distributed teams characterize typical product development environments in industry. But such processes depend to a high degree on the availability of high performing information systems, that enable and support co-operation in distributed teams. In general, the architecture of such systems has to reflect the characteristics of the co-operative business processes to be supported. Although the necessary technologies, like database systems and computer networks are commercially available, the development and entrepreneurial use of distributed systems in engineering is still object of many research projects. The MDB1 developed at Fraunhofer IAO is a prototype of a distributed information system. The system specifically manages material related content. It is currently used as global reference source for material knowledge in a global operating company producing gas turbines.

Cream foam is a polyurethane technology designed for molding foam articles such as automotive headrests or armrests directly into their decorative coverstocks. This process allows for the single step molding of covered foam articles eliminating the secondary step of attaching the cover needed in conventional operations. The advantage cream foam offers over conventional molded foam is that penetration of the stitched seams and foam backing of the coverstock is avoided or controlled. Cream foam technology has improved with the development of a MDI-based polyurethane system that reduces penetration of the foam and fabric bilaminate coverstocks by 25% and the molded foam density by 15%. These improvements result in a cost reduction in the manufacturing of arm or head rests.

A unique low density, water-blown MDI polyurethane foam chemistry has been developed for U.S. Automotive Seating. This breakthrough technology is competitive with incumbent TDI seating systems and can be processed in existing production tools and machinery. Contrary to previously available MDI-based products, this new technology yields densities and Indentation Load Deflections (ILDs) equivalent to what is commonly available with TDI. In addition, a wide firmness range can be achieved by merely changing index, thus eliminating the need for more expensive filled polyols, and multiple systems. A single MDI system can thus be used to produce seat backs, cushions, and dual firmness parts.

Multidisciplinary Design Optimization (MDO) has been widely used in the automotive industry to balance overall weight and stringent vehicle attributes, such as safety, NVH, durability, etc. To improve product quality and shorten product development cycle, a comprehensive MDO-based platform for vehicle attribute integration is developed in this paper. Some key issues in the platform development are addressed: Parameter model synchronization, Metamodel predictive capabilities, and Pre/post processing, etc. In addition, a strategy for body design is proposed to achieve weight targets while meeting other vehicle attributes. Lastly, the proposed methodology is demonstrated by a real world example for vehicle body design.

THE auxiliary transmission and the 2-speed axle are not in direct competition as methods of obtaining multiratio gearing for, as Mr. Wolf points out, neither can fill the field of the other. Where their reduction ratios overlap, Mr. Wolf says that the 2-speed axle is more economical in first cost and can give speedier performance at a lower operating cost. On the other hand, he shows that when larger reductions are required than the 2-speed axle can provide or where three ratios are needed, the auxiliary transmission is without a peer. In general, he says that the type of multiratio gearing that should be used and in what combination depends on the type of truck operation and the degree of economy the operator will obtain from the additional investment.

This paper is concerned with the measurement and prediction of dynamic tire/road interface forces of heavy trucks. The development of equipment to provide continuous, accurate measurement of these forces is discussed. Pavement loads of three test vehicle sunder a variety of speed, load, and road conditions were measured. A time-domain analog simulation technique for predicting dynamic pavement loads based on measured road profiles and known vehicle characteristics is discussed. The simulation was also used to indicate the relative importance of vehicle parameters on dynamic pavement loading.

Smooth operation of motor cars becomes increasingly important as average driving-speeds become higher and as the public demands greater luxury and freedom from vibration. An analysis of vibration shows that it is caused by forces which can be calculated with considerable accuracy. Vibration itself is very complex, due to the inter-relation of forces, deflection and periodicity in the parts of the engine. In this paper a number of indicating and recording instruments devised for recording the actual resultant vibration and determining its exact character are described and their operation explained. Vibration due to unbalance of rotating parts, piston unbalance inherent in four-cylinder engines, bending of the crankshaft, centrifugal force, and torsional periods are discussed. Indicator-diagrams of the various kinds of vibration are shown. Unbalanced force and elastic reaction are the two general causes of vibration.