Partial range scaling method based washout algorithm for a vehicle driving simulator and its evaluation

Unlike an actual vehicle, a vehicle driving simulator (VDS) has limited kinematics, workspace, and bounded dynamic characteristics making it very difficult to simulate dynamic motions of an actual vehicle. To solve these problems, a washout algorithm was developed. The developed algorithm restricts the workspace of the VDS to within the kinematic limit and makes the person driving the VDS perceive movement of an actual vehicle. However, the classic washout algorithm contains several problems, such as time delay and the generation of a wrong motion signal caused by characteristics of the filters. So the driver feels “simulator sickness,” such as fatigue, nausea, headache and so on because of differences between the sense of movement of the VDS and that of a real vehicle. In this paper, a partial range scaling method based washout algorithm, including a tilt coordination system, is developed to enhance the perception of motion and reduce simulator sickness. It is verified by a simulation, a survey, and a bio signal analysis using an electrocardiogram (ECG).     

Simple design approach for improving characteristics of interior permanent magnet synchronous motors for electric air-conditioner systems in HEV

In this paper, a simple design method for improving the performance of an interior permanent magnet synchronous motor (IPMSM), for driving the air-conditioning compressor used in hybrid electric vehicles, is presented. There are many design methods that optimize the IPMSM. Each method deals with a variety of design factors, such as slot opening, pole arc, and rotor shape. However, as the number of design variables increases, a lot of modeling and analysis time is needed in order to improve the characteristics of an IPMSM. This paper demonstrates that the optimization of a double-layer IPMSM, satisfying the given design conditions, is possible with only a flux barrier shape design. Then, response surface methodology is applied as the optimization method, and the validity of the design approach is verified by comparison with test results.     

Simulation of HCCI combustion with spatial inhomogeneities via a locally deterministic approach

There has been recent interest in a new engine type, Homogeneous Charge Compression Ignition (HCCI), to combine the advantages of SI and CI engines. In this paper, a locally deterministic approach is employed to consider spatial inhomogeneities using the KIVA-CHEMKIN package. Validation is performed for two experimental HCCI engines fueled, respectively, by hydrogen and n-heptane. The full mechanism for hydrogen and a skeletal mechanism for n-heptane are used for combustion chemistry. Differences in the reaction flow paths are shown at ignition and the heat release reaction stages of the two fuels. Results show good agreement between measured and calculated pressures for different initial mixture temperatures with estimated residual fractions. A parametric study is performed in both engines to consider the influences of the physical parameters wall temperature, swirl ratio and global equivalence ratio. The ignition time of n-heptane is shown to be relatively insensitive to variations in these parametric due to its two-stage ignition behavior.     

Assessment of an engine cylinder head-block joint using finite element analysis

An engine cylinder head-block joint is a gasketed, bolted joint. Assessment of sealing performance and fatigue durability of the joint during engine development relies entirely on the engine dynamometer test because the rig test cannot mimic the engine run condition and finite element analysis employs gasket and bolt models that are too simple to provide the stress data for fatigue assessment. This paper introduces finite element-based assessment of the gasket and the bolt and a model that improves the analysis accuracy without increasing computation time. Experimental data for the deformation of joint members under thermo-mehanical load are presented to demonstrate the accuracy of the model.     

Multiple criteria evaluation of transportation system improvement projects: The case of korea

As a newly industrialized country, Korea has shown remarkable economic progress in the last three decades. This phenomenal growth has rapidly increased demands for better quality of life. This includes, among others, increasing demand for high quality transportation system services. In this paper, the method of Analytic Hierarchy Process (AHP) is utilized to evaluate rural highway improvement projects in Korea. The appropriate rural highway improvement projects for widening and paving were selected and studied on the basis of some selection criteria. The results have shown that there are some significant differences in prioritizing projects using the traditional economic evaluation method as compared to those resulting from the use of AHP. As demonstrated, the AHP proves to be an effective tool in evaluating transportation system projects.     

Flagging options for the future: A turning point in Korean shipping policy?

The issues surrounding the future of Korea's shipping policy have been heavily debated since 1990 because the Korean shipping industry has been facing rising crew costs and difficulties in recruitment of qualified crew, an adverse taxation system, very limited access to foreign capital markets, and an inflexible government regulatory environment. Consequently, this has contributed to the deterioration of Korea's compectitive edge. This paper aims to provide both an account of the current adverse situtation in Korean shipping business and proposals to alleviate the plight of shipping enterprises. Within the context of that adversity, two solutions are suggested to improve the current situation, by either establishing a Korean second register or flagging out. The paper explores the advantages and disadvantages of each solution. Because ship management is closely interrelated to flagging strategies, the paper also discusses areas of co-operation between Korean shipping or ship management companies and advanced foreign ship management companies.     

The Greening of Ports: A Comparison of Port Management Tools Used by Leading Ports in Asia and Europe

Abstract

From the policy and management perspective, this study aims to investigate the port management tools that port/public authorities have at their disposal and then to analyse to what extent the tools are used to enforce or encourage green port development at functional activities of port operations and development. We conduct an exploratory and comparative review based on two axes: on the one hand, the range of tools available to port authorities (pricing, monitoring and measuring, market access control and environmental standard regulation) and on the other hand, the functional activities in ports (shipping traffic, cargo handling and storage operations, intermodal connection, industrial activities, and port expansion). The situations in the leading ports in Asia and Europe, namely Singapore, Shanghai, Antwerp and Rotterdam are studied and compared, whereby the policies' effectiveness is discussed accordingly. Findings show that the ports are particularly mature in exercising environmental standard regulations which reveals that the enforcement approach is more prevalent. The most focused functional activity is shipping traffic which reflects that the ports are driven by the International Maritime Organisation. The respective port authorities in Antwerp and Rotterdam have a higher level of influence on devising green port policy in comparison to the two Asian ports.     

Sheet metal forming simulation considering die deformation

Due to environmental concerns and safety regulations in the automotive industry, the development of strong and lightweight cars has been a hot issue in the last decade. One solution for this purpose would be to use high-strength steel (HSS) and advanced high-strength steel (AHSS). These materials can make the car lighter while maintaining the crash resistance of the vehicle. HSS and AHSS have more resistance force in the die structure compared with conventional steel due to their higher yield and tensile strength and thus, these materials have a greater effect on die deformation during the sheet metal forming process. As a result, die deformation can affect the blank sheet’s drawn pattern, strain, and stress as well as springback. This study presents a sheet metal forming simulation that considers die deformation. The simulation process was compared with conventional simulation methods. Our results indicate that the sheet metal forming simulation with die deformation consideration provides useful information on the die structure as well as formability and springback.     

Fuel consumption parameters for realizing and verifying fuel consumption prospect algorithm of vehicle driving route information system

Emissions of CO₂, as the main component of greenhouse gases, and high fuel consumption rates are worldwide problems. To solve them, most car manufacturers have concentrated on developing various techniques to improve the efficiencies of engines and transmissions and ECO-ROUTEs to meet environmental regulations. In this study, an algorithm for determining routes that cause the least fuel consumption was developed. The core of this algorithm is a specific EEC (energy efficiency constant) map containing logic that is able to predict fuel consumption. The accuracy of the algorithm was confirmed by vehicle tests for various driving patterns. Parameters affecting vehicle fuel economy were studied and verified. Improvement in the accuracy of this algorithm was confirmed by applying these parameters to ECO-ROUTE logic.     

Torque control of a vehicle with electronic throttle control using an input shaping method

The shock-jerk phenomenon is usually observed in vehicles with manual transmission systems that are rapidly accelerating, and this phenomenon makes the passenger feel uncomfortable. This phenomenon can be minimized using torque control of the vehicle with throttle-by-wire or an ETC (Electronic Throttle Control) system. In this paper, the drivetrain of the vehicle is modeled to simulate the vehicle behavior, and the control strategy of ETC is studied to reduce shock and jerk characteristics using an input shaping method. The control logic is verified by using vehicle modeling and simulations.