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Precision stopping of an urban train at a railway station with platform screen doors is essential to passenger safety and timely revenue service. This paper presents a precision stopping measurement device to automatically detect the position error of an urban train at a railway station with platform screen doors; the device is used primarily for initial calibration during test runs before revenue service begins. The precision stopping measurement device that has been developed is composed of a platform module to detect the stopping error of the train using laser light, a vertical pattern to reflect the laser light, and an on-board module to record the stopping error automatically via wireless communication. The usefulness of the precision stopping measurement device presented here has been demonstrated using field tests with an actual Maglev train in Korea.

Internet generalization has led to increased demands for Internet banking. Various security programs to protect authentication information are being developed; however, these programs cannot protect the wireless communication sections of wireless keyboards. In particular, vulnerabilities have been reported in the radio communication sections of 27 ㎒ wireless keyboards. In this paper, we explain how to analyze M’s 27 ㎒ wireless keyboard. We also experimentally show that an attacker can acquire authentication information during domestic Internet banking using a 27 ㎒ wireless keyboard. To do this, we set up an experimental encironment to analyze the electromagnetic signal of a 27 ㎒ wireless keyboard.

A tilting train is primarily designed to achieve increased speed in a curved section without causing discomfort to passengers. Ensuring the safety of the tilting control system is one of the most important factors in such a train. This paper presents the development of a hydraulic tilting system that can measure the force in real time to find the cause of overcurrent occurring often in an actuator of a Korean tilting train. To smoothly realize tilting motion of the Korean tiling train using hydraulic actuators, the developed hydraulic tilting mechanism was designed such that synchronization control of two hydraulic cylinders installed in opposite directions was possible; furthermore, a cooling system was developed to ensure a test environment with an appropriate temperature. The actual force acting on the two hydraulic cylinders was measured and analyzed for various tilting speed of the Korean tilting train. The experimental results show that the hydraulic tilting actuator system developed for the Korean tilting train is valid. Furthermore, it is shown that two actuator loads are detected successfully acting on the hydraulic tilting system.

The technology development of pipeline transportation of natural gas at artic and northern ice environments should be considered with unique characteristics of permafrost territory as a very interesting and challenging area. This work is to investigate bottleneck techniques and major impact factors through a literature search to figure out the core technology of the transport pipeline. Especially, theoretical approach themes could be determined to develop the technology flow assurance for permafrost regions through documentary survey on the considerations of thermo-fluid. Also, basic results through theoretical approaches could be achieved.

A wheel slide protection (WSP) system of a railway train has the role of reducing excessive wheel slide from brake applications in situations where wheel/rail adhesion is temporarily impaired. The mechanism of the WSP is complex and is related to highly nonlinear dynamics of the train. Hardware-in-the-loop simulation (HILS) for the WSP system can test various dangerous braking conditions which are not possible in actual train tests, and help to find appropriate parameters of the WSP system. This paper presents a HILS unit for the WSP system, which is composed of an actual WSP unit, two actual dump valves, a dSPACE module, and a personal computer with Linux operating system. The dSPACE module simulates railway train dynamics in real-time, which includes dynamic models of wheelsets, bogies, a carbody, and a mechanical brake, and also a dynamic model for creep force generation in wheel/rail contacts. The validity of the HILS system for WSP control is demonstrated by ways of off-line simulation studies and experimental tests using the HILS unit for the Korean tilting train, Hanvit 200.

In order to ensure high performance, all the servers in an existing server cluster are always On regardless of number of real-time requests. They ensure QoS, but waste server power if some of them are idle. To save energy consumed by servers, the server power mode control was developed by shutdowning a server when a server is not needed. There are two types of server power mode control depending on when a server is actually turned off if the server is selected to be off: static or dynamic. In a static mode, the server power is actually turned off after a fixed time delay from the time of the server selection. In a dynamic mode, server power is actually turned off if all the services served in the server are done. This corresponds to a turn off after a variable time delay. The static mdoe has disadvantages. It takes much time to find an optimal shutdown time manually through repeated experiments. In this paper, we propose a dynamic shutdown method to overcome the disadvantages of static shutdown. The proposed method allows to guarantee user QoS with good power-saving because it automatically approaches an optimal shutdown time. We performed experiments using 30 PCs cluster. Experimental results show that the proposed dynamic shutdown method is almost same as the best static shutdown in terms of power saving, but better than the best static shutdown in terms of QoS.

Following the increased use of mobile robots in the field, the injury problem caused by the collision between human and the mobile robot has become an issue of growing importance in the society. Neck injury is considered as one of the major injury mode in collision-induced injury. Hence in this paper, AIS of the neck injury was predicted using the index of neck injury on collision through the mobile robot-dummy collision tests.

Chest injury during unconstrained frontal collision between human and mobile robot is investigated using computer simulation with MADYMO. To assess the chest injury, Combined Thoracic Index (CTI) and Viscous Criteria(VC) was computed. Computed CTI and VC were converted into AIS level by which injury level was evaluated.

In this paper we deal with a hydraulic tilting actuator to make a diagnosis of load characteristic acting on the tilting actuator of the tilting train. Tilting actuator in the tilting train plays a role of making tilt of the train when the train runs a curve section to make the train run without deceleration. However in the process of tilt the tilting actuator is affected by the load acting on the actuator, which has a possibility to make bogie vibration. In order to figure out the effect of the load on the tilting actuator a hydraulic tilting devices that are capable of tilting the train is proposed. The proposed devices are installed in the front bogie and in the rear bogie to make tilting of the train. The devices are consist of sensors that measure the load capacity of the actuator and displacement of the hydraulic cylinder stroke, control blocks to make synchronization of the two actuators, user interface block to monitor the status of the actuators. The effectiveness of the proposed hydraulic tilting actuators is presented by the experimental evaluation using actual tilting train.

This study reports a numerical CFD study concerning the effect of frost thickness on the heat transfer performance of a vertical pipe. Simulation are made under various variables affecting the frost growth such as outer flowing air conditions (temperature, flow velocity, humidity) and inner flow conditions of cryogenic fluid. The frost growth is mainly associated with the outer conditions. The frost thermal conductivity could play an important role in the froth growth. There is no great. The simulation for frost formation carried out with coupling to a commercial CFD code(CFX). The CFD simulation offers the possibility to predict frost formation within vertical geometries. The frost formation is based on the Lewis analogy of heat and mass transfer and it is embedded with CFX. The vertical surface temperature of the freezing body is determined by fluid structure interactive error method.

In this paper a configuration of the load evaluation device for the tilting actuator using hydraulic power is presented, which makes it possible to measure the force action on the tilting actuator. It is possible to measure only current using the conventional electro-mechanical actuator when the bogie is in the process of the tilting. This makes impossible to measure the force acting on the tilting actuator. In order to overcome this problem a kinetic mechanism test system using hydraulic cylinder is proposed. The system are consisted of hydraulic cylinder for the tilting actuation, control system to control hydraulic power, sensors to measure for force and displacement and monitoring system for the user interface.

To maintain the safety and efficiency of railroad vehicles, it is important to understand the working of the brake system with anti-skid control unit (ASCU) for rolling stocks. In this paper, a HILS (Hardware In-the Loop Simulations) system with ASCU hardware (for logic) and a DSP board (for dynamics) is developed to analyze skidding of the Hanvit-200 train during the process of braking. Experimental results are presented for the case that the skid on one of the four wheels is artificially generated using a Simulink model. A convenient GUI is prepared using ControlDesk of dSPACE.

The structural strength tests are usually performed to evaluate the structural strength and to verify the structural design and analysis of the vehicle structures. In this paper, the development of a compressed loading type apparatus to load distributed force over the surface of vehicle structure subjected to external loads was described. This apparatus is for structural materials which are easily to fail because of concentrated stresses. This apparatus can apply loads to specimens without any damage on the test specimen's surfaces by using flexible membrane and can be applicable to several kinds of surface profile of structures. The structural strength tests for the flat structure and curved structure with this apparatus were successfully performed, and the test results showed that this type of loading apparatus can be adequate to verify the structural integrity of the fragile structures. 초 록 일반적으로 기체 구조물 개발시 운용조건에서의 구조설계 해석 검증 및 구조강도확인을 위해서 구조강도시험이 수행된다. 본 논문에서는 구조시험 하중부가방법 중 응력집중에 의해 파손되기 쉬운 재료를 기체 지지구조로 사용하고자 할 때 구조물 표면에 공기압을 이용하여 국부적 응력집중을 피하면서 분포하중을 부가할 수 있는 새로운 외력부가장치의 개발에 대하여 기술하였다. 본 장치는 부드러운 재질의 하중전달용 매개체를 이용하여 구조물 표면에 손상을 주지 않고 외력을 전달할 수 있으며, 임의형상 구조물에 대하여 쉽게 응용이 가능하다. 본 장치를 이용하여 평판구조물과 곡면구조물에 대하여 외력부가 구조강도시험을 성공적으로 수행함으로써 적용시험기법의 타당성을 입증하였다.Key Words : Structural Strength Test (구조강도시험), Compressed Air Type Loading Apparatus(공기압식 외력부가장치), Loading Method(하중부가방법) 376

The Korean tilting train called Hanvit 200 was launched recently in Korea to improve train speed up to 200 km/h at conventional lines. In this paper, we propose a HILS system for simulations of mechanical braking of the Hanvit 200 train using actual ASCU, actual dump valves, Simulink, dSPACE board, and ControlDesk software. In the proposed HILS system, dynamics of wheelsets, bogies and car body, brake force generation, creep force generations are realized via mathematical models, and anti-skid logic is realized using actual components. The validity of the proposed HILS system is demonstrated via comparing results of real-time and off-line simulations.

Traction and braking of trains are due to the rolling contact of the wheel on the rail, and the rolling contact is fundamental to an understanding of the behavior of the railroad system. The way in which the forces are transmitted in the rolling contact is complex and highly nonlinear. This paper describes a rolling contact theory, a creepage model between wheel and rail, and a dynamic model of the tilting train Hanvit-200. The validity of the model is verified through simulation study using Simulink.

The presence of low adhesion at the wheel-rail contact point can result in skid of train wheels, and the skid, in turn, results in flats appearing on the wheels. Thus, anti-skid control has a crucial role for safe braking and prevention from flats that could cause a disastrous train accident. This paper presents dynamic modeling of a tilting train and the brake system of the tilting train, and analyzes the anti-skid logic used in the tilting train. The validity of the analysis is demonstrated via simulation study using Simulink for skid and re-adhesion circumstances of the tilting train.

The general requirements to achieve the structural integrity of the airframe are described in the military specification, MIL-STD-1530A. One of these requirements is the durability and damage tolerance of the airframe, which should be shown through the analysis and test based on the related specifications. This paper introduces the full scale durability test to evaluate the structural safety and durability of the basic trainer, KT-1. The test was performed according to the procedure in the military specification. The flight by flight load spectrum was developed by KT-1 fatigue load criteria and used for the durability test. The durability test had been performed for 4 service lives and was completed successfully. Therefore, it was shown that KT-1 airframe satisfied the durability requirements.

A hydraulic actuation system for a tilting train is usually composed of independent actuators to remove position errors due to bulk modulus of the hydraulic system. For the hydraulic control system using two independent cylinders, this paper presents the modeling of the hydraulic system, control logic, and simulation results of the hydraulic control system. Simulation results for motion responses of two cylinders using position commands calculated from tilting angles show the validity of the proposed hydraulic two-actuator system.

With the development of the Wireless Sensor Network (WSN) technology, ubiquitous technology comes to the fore as the core technology in the future. In the Wireless Sensor Network, energy efficiency of the whole network is a key problem that has to be solved. Clustering is one of routing techniques to improve energy efficiency. LEACH and LEACH-C are existing techniques focused on optimizing energy efficiency of the network by applying clustering. However, those protocols still have problems. LEACH does not guarantee balanced distribution of cluster heads and communication overhead of LEACH-C is quite heavy. In this paper, therefore, we suggest a new method, “Energy-Efficient Clustering scheme with Concentric Hierarchy (EECCH),” a centralized clustering scheme aimed at overcoming weaknesses of LEACH and LEACH-C both. By drawing circles with the base station as its center, the base station separates network nodes into some levels. Afterward, we let the clusters have different numbers of its member nodes to eliminate inequality in energy dissipation. Through this process, it becomes possible to improve energy efficiency. By using MATLAB, we prove that EECCH gives better performance than some other protocols which also use clustering technique, including LEACH, in the performance evaluation.

This paper presents a real-time simulation for the brake system including ASCU hardware component of the Korean tilting train. The dynamic model of the rolling stock is implemented using a dSPACE board and Simulink programs. Dump valve signals are fed back to dSPACE board and wheel speeds are generated by the dynamic model using the feedback signals. The validity of this real-time simulation module is demonstrated by executing this ASCU HILS system for various skid conditions.

Traction of trains is due to the rolling contact of the wheel on the rail, and the rolling contact is fundamental to an understanding of the behavior of the railroad system. The way in which the forces are transmitted in the rolling contact is complex and highly nonlinear. This paper presents rolling contact phenomena of the wheel on the rail, creepages on the wheel/rail contacts, and creep force models. The validity of the proposed models is verified through simulation study using Simulink for the tilting train, Hanvit-200 (TTX).