• 한국산학기술학회논문지
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• 제11권12호
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• pp.5207-5215
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• 2010

단지계획 또는 특정 목적의 시설물 설립을 위한 적지선정은 제반여건과 주변환경을 면밀하게 고려해야 한다. 특히, 인간의 생활공간이라면 채광 및 통풍, 부지활용의 효용성 등이 중요한 요소이다. 이를 위해서 3차원 지형 모델링과 가상 시뮬레이션을 통한 다각적인 입체분석이 필요하다. 이러한 지형모델링에 필수적인 고해상 위성영상이 아리랑2호 위성(KOMPSAT2)을 통해 국내기술로 제공되고 있으므로 저렴한 비용으로 처리가 가능해 졌다. 본 연구에서는 특정목적의 단지계획을 위해 몇 개의 후보지를 선정하고 3차원 지형모델링과 토지정보를 이용하여 적지분석을 하고자 하였다. 이를 위해 필지분석, 지가산정, 경사도 분석, 향분석을 실시하였으며 각 후보지 별 평가지표를 마련하여 정량적인 평가를 시도한 결과 효율적이며 합리적으로 적지선정을 할 수 있었다.

• 한국환경과학회지
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• 제14권3호
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• pp.297-309
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• 2005

Recently air quality modeling studies for industrial complex and large cities located in the coastal regions have been carried out Especially, the representation of atmospheric flow fields within a model domain is very important, because an adequate air quality simulation requires an accurate portrayal of the realistic three­dimensional wind fields. Therefore this study investigated effect of using high resolution terrain height data and FDDA with observational data to reflect local characteristics in numerical simulation. So the experiments were designed according to FDDA and the detail terrain height with 3sec resolution or not Case 30s was the experiment using the terrain height data of USGS without FDDA and Case 3s was the experiment using the detail terrain height data of Ministry of Environment without FDDA and Case 3sF was experiment using the detail terrain height data of Ministry of Environment with FDDA. The results of experiments were more remarkable, In Case 3s and Case 3sF, temperature indicated similar tendency comparing to observational data predicting maximum temperature during the daytime and wind speed made weakly for difference of terrain height Also Case 3sF had more adequate tendency than Case 3s at dawn.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.333-334
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• 2002

Injection-compression molding parts are many cases with complicated boundary condition which is difficult to analysis of mold characteristics precisely. In this study, the effects of various process parameters such as multi-point gate location, initial charge volume, injection time and pressure have been investigated using finite element method to fomulate the melt front advancement during the mold filling process. A general governing equation for tracking the filling process during injection-compression molding is applied to volume of fluid method. To verify the results of present analysis, they are compared with those of the other paper. The results show a strong effect of processing conditions as a result of variations in the three-dimensional complex geometry model.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1123-1126
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• 2005

This paper introduces the key features of NCS (Network based Control System), which is quite a new concept in the industrial automation market. Two control systems "DCS" and "PLC" have been recognized as control systems used for process and factory automation during the past decades. However, the market requires more complex functionality, such as monitoring and operation, alarm handling and notification from remote locations using the Web or e-mail. Besides enhancing functionality, interoperability between each device and system is highly required since network and engineering tools provided by many vendors do not cooperate with each others, so that lots of conversion, reconfiguration and reprogramming are required when expanding systems. NCS can meet this requirement, installing leading-edged IT technology using international standards for network and engineering environment. NCS, which is a harmony of web functionality, networkability and a reliable control function, enables information integration and responding to the market's requirements with agility and high reliability.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.350-350
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• 2000

Since the heat exchange system, such as the boiler of power plant, gas turbine, and radiator require a high rate heat efficiency and the efficiency of these systems is depended on the control methods. However, it is important f3r operator to understand control system of these systems. In order to properly apply control equipment to these process control systems, such as boiler, any other heat process, or process control system it is necessary to understand the basic aspects and operation principle of the process that relate control, interrelationships of the process characteristics, and the dynamics that are involved. Generally, PID controllers are used in these systems but it is difficult for engineer to understand the complex dynamics and the tuning method because of the coupling action and disturbance in the system loop. In this paper, we design an effective experimental system fur automatic control education and analyze its characteristics through experimental system and industrial plant control software to study how they can team automatic control system by experiments.

• International Journal of Automotive Technology
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• 제7권2호
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• pp.121-128
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• 2006

The interaction between adherent molecules and gas molecules was modeled in the molecular scale and simulated by the molecular dynamics method in order to understand evaporation and removal processes of adherent molecules on metallic surface using high temperature gas flow. Methanol molecules were chosen as adherent molecules to investigate effects of adhesion quantity and gas molecular collisions because the industrial oil has too complex structures of fatty acid. Effects of adherent quantity, gas temperature, surface temperature and adhesion strength for the evaporation rate of adherent molecules and the molecular removal mechanism were investigated and discussed in the present study. Evaporation and removal rates of adherent molecules from metallic surface calculated by the molecular dynamics method showed the similar dependence on the surface temperature shown in the experimental results.

• 대한안전경영과학회지
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• 제12권2호
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• pp.99-105
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• 2010

In this paper, the uAPSS(u-APartment Service System) that is based on location-aware technology is designed and implemented for a luxury apartment. On the real luxury apartment the developed system has been employed and tested to provide convenient and secure living for residents. It provides services such as emergency call, intelligent elevator operation, and hands-free door access based on the location of the residents with personal device as called smart tag. It can also be applied to other service areas such as the location-aware u-Service for hospitals, high-rising complex buildings, silver towns, etc.

• 한국산학기술학회논문지
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• 제10권6호
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• pp.1214-1219
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• 2009

USN(Ubiquitous Sensor Network) 기술이 발전하면서 다양한 분야에서 이를 활용하기 위한 연구들이 활발하게 진행되고 있다. 특히 물류관리 분야에서의 연구가 활발히 진행되고, 세계적인 대형마트 및 대형 물류 창고 등과 연계되어 실제 적용되고 있다. 이렇게 활용도가 높아지고 있는 USN 기술이지만, 완벽하게 실시간으로 데이터처리를 하기란 쉽지 않다. 수천, 수만 개의 센서를 사용하는 초대형 물류창고와 같이 대량의 데이터 값이 오차 없이 수집되어야 하는 분야의 경우, 기존의 데이터처리 방식으로는 실시간 데이터를 수집의 효율성이 낮을 수밖에 없다. 이와 맞물려 하드웨어의 고속화는 이루어졌지만, 소프트웨어적 구현이 미미한 현재, 이러한 문제점을 해결하기 위하여 파이프라인 기법을 통한 소프트웨어 고속화를 실현 시키는 것이 관건이다. 따라서 본 논문에서는 파이프라이닝 기법을 적용하여 물류관리 시스템의 실시간 데이터 수집의 효율성을 높이고 값의 오차를 줄일 수 있는 USN 물류관리 시스템을 제안하였다.

• 한국산업정보학회논문지
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• 제17권2호
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• pp.19-27
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• 2012

In railway tunnel environment, the reliability of a high-data-rate and real-time train-to-wayside communication should be maintained especially when high-speed train moves along the track. In China and Europe, the communication frequency around 900 MHz is widely used for railway applications. At this carrier frequency band, both of the solutions based on continuously laid leaky coaxial cable (LCX) and discretely installed base-station antennas (BSAs), are applied in tunnel radio coverage. Many available works have concentrated on the radio-wave propagation in tunnels by different kinds of prediction models. Most of them solve this problem as natural propagation in a relatively large hollow waveguide, by neglecting the transmitting/receiving (Tx/Rx) components. However, within such confined areas like railway tunnels especially loaded with train, the complex communication environment becomes an important factor that would affect the quality of the signal transmission. This paper will apply a full-wave numerical method to this case, for considering the BSA or LCX, train antennas and their interacted environments, such as the locomotive body, overhead line for power supply, locomotive pantograph, steel rails, ballastless track, tunnel walls, etc.. Involving finite-difference time-domain (FDTD) method and uni-axial anisotropic perfectly matched layer (UPML) technique, the entire wireless RF downlinks of BSA and LCX to tunnel space to train antenna are precisely modeled (so-called integrative modeling technique, IMT). When exciting the BSA and LCX separately, the field distributions of some cross-sections in a rectangular tunnel are presented. It can be found that the influence of the locomotive body and other tunnel environments is very significant. The field coverage on the locomotive roof plane where the train antennas mounted, seems more homogenous when the side-laying position of the BSA or LCX is much higher. Also, much smoother field coverage solution is achieved by choosing LCX for its characteristic of more homogenous electromagnetic wave radiation.

• 한국해양공학회지
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• 제28권2호
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• pp.160-166
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• 2014

Because of industrial development, industrial facilities are becoming more complex and diversified. Plant industries are focused on productivity improvement, cost reduction, and product uniformity by simplifying production processes using automated control. Furthermore, plant industries require higher pressures and temperatures to improve energy efficiency. For this reason, the valves used in plants are operated under harsh conditions. Globe valves and gate valves are mainly used for high pressure these days. However, these valves have various problems, including low maintainability and high cost, due to structural problems. Therefore, butterfly and ball valve applications are increasing in industrial plants. This paper suggests a quadruple-offset butterfly valve that is applicable to bi-direction use, and the principle design parameters are suggested. The selected design parameters are an eccentric flange center line and shaft centerline(Offset 1), an eccentric seat centerline and disc shaft centerline(Offset 2), the angle between the flange centerline and seat wedge angle(Offset 3), the angle between the vertical direction of the disc shaft centerline and seat centerline(Offset 4), and the seat engagement angle. To analyze the interaction effect of the design parameters, ANOM and ANOVA were performed with an orthogonal array. The parameters were found to have effects in the following order: Offset 2, Offset 1, engagement angle, Offset 3, and Offset 4. The interaction between the parameters was insignificant.