• 반도체디스플레이기술학회지
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• 제2권2호
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• pp.25-30
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• 2003

In the case of a vibration sensitive equipment, it require a vibration free environment to provide its proper function. Especially, lithography and inspection device, which have sub-nanometer class high accuracy and resolution, have come to necessity for producing more improved Giga Class semi conductor wafers. This high technology equipments require very strict environmental vibration criteria in proportion to the accuracy of the manufacturing. In this paper, the dynamic analysis and modal test were performed to evaluate the dynamic properties of the constructing clean room structure. Based on these results, a structural dynamic modification(SDM) were required to satisfiy the vibration allowable limit for pression machine. Therefore, in order to improve the dynamic stiffness of clean room structure, the VSD system which can control the force applied on structure, were adopted and its utility were proved from dynamic test results of the improved structure after a modification work.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.1233-1238
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• 2007

In recently, our social is entering to service infinite competitive time., So If companys don't give satifactory and an impression customers, they don't exist. The Companies that operate railway are promoted(Seoul metro). The Korail, Seol metropolitan Rapid Transit Corperation, Incheon Rapid Transit Corporation), they are into a stronger competitor. So the service for customer is more inportant to improve the image and administration than before. Especially, station workers who work near the customer are important for cooperation image. But, there are only a few employees to operate the station like ticketing in railway station, There aren't reinforcement the service employees and expanse the utility system. especially, since the transportation card is introduced in 1996, the customers who use the T-Money card are increased. So the change of service system is necessary to provide a substantial service to customer. This paper derives the problems through analysising the operating system of station, and presents the improvement to provide substantial services to customer

• 항공우주시스템공학회지
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• 제2권3호
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• pp.29-32
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• 2008

The overview of KUH design and development process is presented according to Buede's systems and development "vee" model. The system decomposition and integration activities exemplify KUH specification tree, design maturity and analysis according to design stage(conceptual, preliminary, and detail design), scheduled work breakdown structure, qualification test, ground test, and flight test. This process can be applied to the development of a new aircraft.

• 한국가정과교육학회지
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• 제4권1호
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• pp.31-41
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• 1992

The central goal of this study is to find out of the boy students in middle school the attitude towards house life and house-hold affairs of the boys； and explain what will be of their attitude after they have got Home Economics education. For the purpose of this study, 138 questionairs were distributed to the boy students who had educated Home Economics in school and the ones who had not. The results were as follows； 1. The educated group has higher score in ability of house-hold making than the other group. 2. The educated students responed affirmatively to the utility and necessity of Home Economics education. 3. The teachers who have taught Home Economics to male students have opinions that the students needed Home Economics education to increase the ability of doing house-hold work. Accordingly, Home Economics education should be taught to both sexes in order to have good quality of life, and requires more hours to study as well.

• 한국연소학회:학술대회논문집
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• 한국연소학회 1995년도 제2회 KOSCI Workshop
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• pp.91-103
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• 1995

In recent years, significant advances have been made in the development of methods to predict ash behavior in utility boilers. This paper provides an overview of methods used to assess and predict ash formation and deposition. It has discussed some of the key problems associated with the formation and deposition of ash during the combustion of pulverized coal. Although considerable progress has been made in understanding of the fundamental mechanisms of ash formation, transport, growth, and strength development, there is still much work to be done. There is a need to develop quantitative relationships between the characteristics of the entrained ash and the physical properties of ash deposits that influence deposit growth, strength development, and cleanability. Also data from bench-scale, pilot-scale, and full-scale units are needed in order to determine operating conditions which will minimize deposition problems, maximize efficiency, and reduce emissions.

• 대한기계학회논문집B
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• 제29권11호
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• pp.1220-1228
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• 2005

Fault detection and diagnostic (FDD) systems have the potential to reduce equipment downtime, service costs, and utility costs. In this study, model based algorithm and fuzzy algorithm were used to detect and diagnose various fault at System multi-air conditioner. various fault include the Refrigerant Low charging, Fouling of Indoor Heat Exchanger, Fouling of Outdoor Heat Exchanger A experimental verification was conducted in the 6HP System multi-air conditioner on an 8-floor building. Test results showed diagnosis result about 78 $\~$ 90$\%$ for given faults. This Study lays the foundation fur future work on develope the real-time fault detection and diagnosis system for the System multi-air conditioner.

• 대한교통학회지
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• 제14권4호
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• pp.31-48
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• 1996

This paper develops a disaggregate model system for travel behavior of workers in a metropolitan area. We attempt to develop a set of models for predicting trip generation type, trip purpose, destination, mode choices in each trip on the way from work to home by using the concept of utility maximization of base-to-base tour. The model incorporates the concept that decisions of a trip in a trip in a travel tour depend on decisions of the trips having been made before and decisions of trip planned after of this trip, as well as on current trip conditions. As the structure of the model, the nested logit model is used to avoid a simultaneous model's complexity. The data to be used for estimating the model system are from the person trip survey which was carried out in 1981 in Nagoya metropolitan. Empirical tests of the model for Nagoya metropolitan area show encouraging results and prove the validity of the assumption of this model.

• 한국병원경영학회지
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• 제15권4호
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• pp.100-124
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• 2010

This work was researched by practical method in a subjectivity study accessible in-depth, in sloughing off old habit of functional quantity analysis about Reception Type on policy reception of public & health campaign. The perception pattern come out in this study were divided into four types in Q-methodology. The result is as follows ; it is that divided'1[(N=16): Policy Improvement Type], 2[(N=7) : Public-relation Utility Type], 3[(N=19): Financial-continuance Type], 4[(N=11) : Healthy-prevention Orientation Type]'. Like this, it found that is very different type all over. Hereafter, this study is to ascertain acceptance behavior about Reception Type on policy reception of public & health campaign ; to offer a developmental suggestion about it.

• Journal of Communications and Networks
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• 제11권5호
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• pp.489-499
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• 2009

We describe the fundamental issue of scheduling the allocation of wireless network resources and provide several formulations of the associated problems. The emphasis is on scheduling transmission attempts. We place this problem in the context of existing approaches, like information theoretic and traditional network theoretic ones, as well as novel avenues that open up the possibility of addressing this issue for non-stationary and non-ergodic environments. We summarize concrete recent results for specific special cases that include unicast and multicast traffic, different objective functions, and reduced complexity versions of the problem. We conclude with some thoughts for future work. We identify and single out the cross-layer nature of the problem and include a simple physical-layer criterion in what is mostly a medium access control (MAC) problem.

• Steel and Composite Structures
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• 제5권6호
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• pp.421-441
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• 2005

The present work reports on a numerical simulation of a compartment fire. The fire was modeled using a simplified approach, where combustion is simulated as a volumetric heat release. Computations were performed with the commercial code CFX 5.6. Radiation was modeled with a differential approximation (P1 model), while turbulence effects upon the mean gas flow were dealt with a SST turbulence model. Simulations were carried out using a transient approach, starting at the onset of ignition. Results are provided for the temperature field time evolution, thus allowing a direct comparison with the analytical and experimental data. The high spatial resolution available for the results proved to be of great utility for a more detailed analysis of the thermal impact on the steel structure.