• Analytical Science and Technology
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• v.18 no.1
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• pp.74-84
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• 2005

Understandings of adsorption characteristic of interface are very important in several advanced materials processes, related to NT and BT technology. Volumetric gas adsorption method, suitable for absolute measurements, is regarded as the standardized measurement technique for specific surface area. In order to verify the reliability of commercial equipments, certified reference materials (called CRM) of specific surface area are developed and evaluated its uncertainty factors by standard equipment which has traceability to SI units. Specific surface areas of developed materials are $10.72{\pm}0.46m^2g^{-1}$ for silicon nitride powders and $149.50{\pm}3.44m^2g^{-1}$ for alumina. These disseminations of CRMs would result in improved reliability chains in industrial processes, and lead eventually to contribution to productivity improvement, quality management, safety evaluation, and possibly to new material development.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.8
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• pp.1064-1069
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• 2014

The railway signalling system plays an essential role in the headway and routing control for a safe and efficient train operation. The reliable and safe operation of the system is very important because the failure of the railway signalling system can lead to the collision, derailment, or unexpected stop of a train. So far, the conventional wayside signal mode (ATS: Automatic Train Stop) has been generally used as the railway signalling system. However, this system is highly linked to a risk of major accidents resulted from human mistakes such as missing a signal or careless control of train speed. Accordingly, the onboard signal mode (ATC: Automatic Train Control) as an alternative of ATS has been recently introduced and applied to transmit effectively the information on speed control of a train by using computers and communication equipment. In the process of replacing the obsolete signal system, it is necessary to switch over the system while providing passengers with normal services. Therefore, the integration of a railway signaling system compatible for both ATS and ATC and its interface is discussed in this study. In particular, the implementation scenario required for operation planning of the integrated system was designed, and the results as well as effects of its applicability test were also presented.

• Journal of the Korea Computer Industry Society
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• v.7 no.4
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• pp.437-446
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• 2006

Mobilecomputer offers more fundamental role than role assistance enemy of modern technology equipment and new Information <중략> These main weakness puts in structural relation between elements that compose system. Therefore, dynamics research that time urea of systematic adjustment has selected method code Tuesday nerve dynamics enemy who groping of approach that become analysis point is proper and do with recycling bioelectricity signal. Nature model of do living body signal digital analysis chapter as research result could be developed and scientific foundation groping could apply HSS (Hardware-software system) by rehalibitation purpose. Special quality that is done radish form Tuesday of bioelectricity signal formation furthermore studied, and by the result, fundamental process of bodysignal in do structure circuit form of analog - digital water supply height modelling do can.

• Bulletin of the Korean Space Science Society
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• 2003.10a
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• pp.91-91
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• 2003

위성을 발사하기 전까지는 지상에서 EGSE(Electrical Ground Support Equipment)를 이용하여 충분한 시스템 단위의 위성체 기능 시험을 수행한다. KOMPSAT-2(Korea Multi-Purpose Satellite - 2)와 같은 소형 위성의 서브시스템 각각이 요구사항에서 제시하는 규격을 만족하는지 여부를 점검하는 단계에서 전력계 관련 서브시스템의 기능 시험도 EPS(Electrical Power Subsystem) Test Plan에 의해 순차적으로 수행한다. KOMPSAT-2 ETB(Engineering Test Bed)에서의 전력계 시험은 먼저 Test Fuse Modules Check를 수행하였다. 퓨즈 모듈은 PCU(Power Control Unit) 상에 설치되어 있는 장치로써 퓨즈 모듈의 입력과 출력 사이에 도통성 및 다른 출력과의 절연성을 검증한다. 다음으로 EGSE 중 PMTS(Power Monitor Test Set)와 PCU와의 직렬 인터페이스를 점검하는 PCU Interface Check를 수행하였다 시험절차서에 따라 PCU가 가지는 릴레이 스위치에 대하여 명령어를 보내어 릴레이의 동작 상태 및 출력 전압 등을 점검한다. 다음 단계에서는 DC Integration을 수행하여 ETB 하니스 중 전원 관련 라인을 점검하였다 PCU는 모든 위성체 하드웨어에 전력을 공급하는 장비로써 과전력으로부터 하드웨어를 보호하기 위하여 하니스를 연결하기 전에 우선적으로 시험한다. 다음으로는 ECU(EPS Control Unit)가 각각에 해당하는 하드웨어에 명령어를 보내어 전력계 전체적인 동작 상태 검증하는 EPS Hardware Command & Telemetry Checkout을 수행하였다. ECU는 전력계의 모든 하드웨어를 제어하고 그 상태를 모니터링하는 기능을 한다. PCU와의 인터페이스를 통하여 전력의 제어 및 분배에 관련되는 특성을 제어 및 모니터하며 DDC(Deploy Device Controller)는 ECU로부터 명령어를 받아서 arm 및 safe 상태에 대한 텔리 메트리 데이터를 제공한다 그리고, SAR(Solar Array Regulator)는 ECU로부터 Bypass Relay 및 ARM Relay에 관한 명령어를 받아 수행되며 그에 따른 텔리 메트리 데이터를 제공한다. 마지막으로 EPS 소프트웨어를 검증하는 EPS Software Verification을 수행하였다 전력계 소프트웨어의 설계의 검증 부분은 현재 설계 제작된 전력계 .소프트웨어의 동작 특성 이 위성 의 전체 운용개념과 연계하여 전력계 소프트웨어가 전력계 및 위성체의 요구조건을 만족시키는지를 확인하는데 있다. 전력계 운용 소프트웨어는 배터리의 충ㆍ방전을 효율적으로 관리해 3년의 임무 기간동안 위성체에 전력을 공급할 수 있도록 설계되어 있다

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.11
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• pp.6821-6829
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• 2014

The use of semiconductor devices as a component of eco-friendly motor vehicles has increased and their widespread use as high voltage switches is expected. On the other hand, in the case of high-voltage switches, reliability test equipment is not localized. To test high voltage switches, this paper analyzed the relevant test standards for developing power supplies. In particular, for the automotive semiconductor reliability test, the AEC (Automotive Electronic Council) Q101 was analyzed. Based on that, the standard specifications of the power supply were determined. For the main power circuit, the pull bridge converter was adopted and based on the specification, the circuit parameters were determined and verified by simulation. The interface for the parallel and pattern operation was designed. The characteristics of the power supply were tested.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.2
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• pp.131-141
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• 2012

A large fraction of urban $PM_{10}$ concentrations is due to non-exhaust traffic emissions including road dust, tire wear particles, and brake lining particles. Although potential health and environmental impacts associated with tire wear debris have increased, few environmentally and biologically relevant studies of actual tire wear debris have been conducted. Tire wear particles (TWP) are released from the tire tread as a result of the interaction between the tire and the pavement. Roadway particles (RP), meanwhile, are particles on roads composed of a mixture of elements from tires, pavements, fuels, brakes, and environmental dust. The main objective of present study is to identify the contribution of tires to the generation of RP and to assess the potential environmental and health impacts of this contribution. First, a mobile measurement system was constructed and used to measure the RP on asphalt roads according to vehicle speed. The equipment of the mobile system provides $PM_{10}$ concentrations by Dusttrak DRX and number density & size distribution measurements of fine and ultra-fine particles by a fast mobility particle sizer (FMPS) and an aerosol particle sizer (APS). When traveling on an asphalt road at constant speed, there is a clear tendency for $PM_{10}$ concentration to increase slightly in accordance with an increase in the vehicle speed. It was also found that considerable brake wear particles and particles from tire/road interface were generated by rapid deceleration of the vehicle. As a result, the $PM_{10}$ concentration and particle number of ultra-fine particles were measured to be very high.

• The Journal of the Korea Contents Association
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• v.20 no.9
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• pp.271-284
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• 2020

Good reviews that Half-Life: Alyx received created a turning point for the vitalization of the VR market with an uncertain future due to the absence of a revenue model together with the increased sales of VR equipment. Based on previous studies, this study categorized the characteristics of VR games according to graphs, first-person system, interface, controller, interaction technology, sound and stories. The analysis results show that the seven elements corresponded with "interactions" and "virtual images," which represent the completion level of games as part of VR components, and were connected to one another, which led to the proposal of an upper-rank concept "presence" to put them together. "Immersiveness," which represents users' emotions as part of VR components, was analyzed with the immersion theory to assign tasks of proper difficulty level for users' abilities. In the research process, the Delphi technique and FGI were administered to a panel of 15 experts to ensure objectivity. Finally, "presence" and "immersiveness" are characteristics in proportion to each other and can be valid concepts in future analysis of VR games as well as Half-Life: Alyx, which led to the proposal a new concept framework called 'presence effects' by combining the two words.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.9B
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• pp.760-766
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• 2008

As a backbone network, wireless mesh network (WMN) aims to provide reliable high throughput network connectivity to wireless users. Recent research has focused on routing and channel allocation to increase the capacity of wireless mesh backbones. Wireless mesh networking is an attractive solution for home, community, and enterprise networks as it is a self-configuring, instantly deployable, and lowcost networking system. In this paper, we empirically evaluate and analyze charateristic of WMN to establish WMN testbed by measurement. We use laptops and net4826 Soekris board widely used. Soekris boards are equipped with one network interface card (NIC) or above in our measurements. We also use paket generator, routing demon tools and so on. Throughout this measurements, we show limitation of Soekris board and software we use, and suggest guideline to establish WMN.

• Proceedings of the KIEE Conference
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• 2006.07d
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• pp.2167-2168
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• 2006

Mobilecomputer of offers more fundamental role than role assistance enemy of modem technology equipment and new Information Technology can reconsider, and reconstruct creatively accuracy of physiological concept. That military register symptoms are developed of disease, before far before rehalibitation, of for possibility that can intervene in process that motive change of military register symptoms after rehalibitation. But, that many parameters become analysis target and mathematical settlement and equalization system of noted data of that is huge, same time collection of all datas can lift difficulty etc.. These main weakness puts in structural relation between elements that compose system. Therefore, dynamics research that time urea of systematic adjustment has selected method code Tuesday nerve dynamics enemy who groping of approach that become analysis point is proper and do with recycling bioelectricity signal. Nature model of do living body signal digital analysis chapter as research result could be developed and scientific foundation groping could apply HSS (Hardware-software system) by rehalibitation purpose. Special quality that isdone radish form Tuesday of bioelectricity signal formation furthermore studied, and by the result, fundamental process of bodysignal in do structure circuit form of analog - digital water supply height modelling do can.

• Tunnel and Underground Space
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• v.24 no.2
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• pp.111-119
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• 2014

This study developed a Windows-based simulation program for selecting equipments in open-pit shovel-truck haulage systems. Visual Basic.NET 2012 was used to develop the graphic user interface (GUI) and the GPSS/H simulation language was utilized to implement the simulation engine of program. When users establish simulation parameters through the GUI, the program calls the simulation engine to perform the simulations repeatedly. Then, it finds the optimal fleet of equipments required for operating the open-pit shovel-truck haulage systems efficiently. Application of the program to the Ssangyong open-pit limestone mine, Gangwon-do, Korea, showed that the daily average profit of shovel-truck haulage operation can be maximized (i.e. 88,552 USD) under following conditions: (a) 4 trucks are dispatched into each loading point and (b) a crusher with capacity of 1,500tph is utilized.