• Journal of the Korean Institute of Telematics and Electronics D
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• v.36D no.9
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• pp.21-30
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• 1999

Halo pocket implantation in MOSFETs, which is known to be an efficient method to provent the punchthrough and threshold voltage roll-off phenomena, decreases the drain current of MOSFET devices. Although the decrease of the drain current in halo structure MOSFET is usually explained in terms of the increase of the threshold voltage, more decrease in the drain current than is predicted by the increased threshold voltage has experimentally been observed. In this work, the effect of halo doping profile on the drain current degradation is investigated in terms of the field distribution along the channel. Effective mobility model of the halo MOSFETs due to pocket implantation is presented and the degradation of the mobility is shown to be effective in the further decrease of the drain current. Present model is shown to be in good agreement with experimental results.

• Water for future
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• v.13 no.2
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• pp.55-62
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• 1980

It is very important thing that the high tide prediction along the sea-side before the typhoon landing. In Korea, every year somewhere of the near sea-shore has been suffered much damages by the high tide during typhoon season, and the governement has to spend much of the reserved budget to rescue and reconstruction the damaged facilities in the seas-shore area. In this point of view, as none of the high tide prediction program in Korea, the author aims to develope this kind of study, so that this application program may dedicate the concerned organizations such as Ministry of Construction, Commerce and Industry, and Agriculture Forestry and Fishery, etc. Due to developed the software of high speed electronic computer in recently, the complicated numerical analysis can be solve very conviniently. So the author tries to prepare the high tide predecation program using the equation of motion and continous in the fluide dynamics by the constant time and distance of the differentation method. The input data for this program are the weather chart and depth data of the mattered bay, inner-sea or outer-sea. This program has been applied on the Pohan inner harbor as a model and find ort the program computation results is coincide with the observed values of "FRAN" typhoon in 1976 at the Pohang harbor.ng harbor.

• Journal of Korea Water Resources Association
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• v.42 no.4
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• pp.297-307
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• 2009

For reliable water quality simulation by semi distributed model, accurate daily runoff simulation should have preceded. In this study, newly developed channel routing method which is nonlinear storage method is combination of Muskingum routing method and variable storage routing method and temporally weighted average curve number method were applied for effect analysis of water quality simulation. Developed modules, which are added in SWAT models and simulation, were conducted for the Chungju dam watershed. The simulation result by each module applied effect. As a result of analysis contribute water quality modeling, nonlinear storage method is more effective than temporally weighted average curve number method. Nutrient loading discharge was affected by development of runoff delaying from improvement of channel routing, because of characteristics of nonpoint source pollution.

• The Journal of the Acoustical Society of Korea
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• v.13 no.6
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• pp.50-59
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• 1994

Spectral analysis of transient elastic waves were carried out in order to identify the propagation modes in glass and unidirectional carbon fibre reinforced plastic (CFRP) plates. Pencil leads were broken on the surface of plates to generate elastic waves, and two broad band transducers of 6.35 mm in diameter and 10 MHz center frequency were placed at the linear location from the source. The frequency spectra of detected signals showed that the wave propagation in the plates obeyed the Lamb wave dispersion relation. The transient signals were the fast propagating modes around maximum group velocity of the lowest and first order symmetric $modes(S_{0} and S_{1}),$ and first order antisymmetric $mode(A_{1})$. The transient signals were not severely distorted due to relatively small dispersion of those modes around the maximum group velocity. The fastest propagating mode in the plates was shown to be $S_{0}$ mode less the than cut-off frequency of $A_{1}$ mode.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.53-53
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• 2011

최근에 세계화, 무역자유화에 따른 컨테이너 물동량이 증가하고 있다. 그에 발맞추어 초대형 컨테이너선이 등장하게 되고 신개념, 고효율의 항만인프라의 도입이 요구되고 있다. 이런 배경에 따라 최근에 국내외에서 부유식 안벽에 관한 기술 개발 및 연구가 더욱 필요한 상황이다. 부유식 안벽은 이동가능한 부유식 구조로 기존 항만의 확장 또는 신규 항만 건설시 환경문제를 최소화하고 기항, 선박수 및 선박의 크기에 따른 안벽 배열을 최적화 할 수 있어 항만 기능을 고도화함으로써 녹색항만을 구현하는데 많은 기여를 하게 될 것이다. 특히 컨테이너선의 양현하역과 환적이 가능하게 되어 컨테이너 터미널의 화물처리능력을 확대할 수 있을 뿐 아니라 기항선박의 체류시간을 최소화 할 수 있는 장점이 있다. 또한, 우리나라는 삼면이 바다로 크고 작은 항만들이 해안선을 따라 위치하고 있다. 이러한 항만들을 안전하게 보호하기 위한 방파제는 항만 기본시설인 외곽시설 중의 가장 중요한 구조물이다. 국내에 설치된 방파제는 대부분 사석이나 케이슨을 이용한 중력식 방파제로써 해저에 고정되어 해수면상으로 건설되므로 항내 외 해수교환을 차단하여 항내 수질악화를 초래할 뿐만 아니라 수심에 따라 막대한 건설비용이 소요된다. 따라서 친환경적이고 경제적인 새로운 형식의 방파제에 대한 연구 및 개발이 필요한 실정이다. 그 중 하나의 대안인 부유식 방파제는 공사기간이 짧고 비교적 수심에 대한 제약이 없는 것이 특징이다. 또한 해수의 원활한 흐름이 가능하기 때문에 중력식 방파제에 비해 경제적이며, 환경적 측면에서 큰 장점이 있다. 하지만 아직까지 부유식 방파제에 대한 국내 및 해외에서의 연구는 이론적인 해석을 중심으로 이루어져 부유식 방파제 실용화를 위한 많은 연구가 수행되어야 할 것으로 판단된다. 본 연구에서는 부유식 안벽 내에서 정온도를 효과적으로 유지하기 위하여 부유식 방파제를 설치하고 소파성능과 부유식 안벽내의 영향성을 수리모형실험을 통해 분석하였다.

• Journal of Korean Society for Geospatial Information Science
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• v.10 no.2 s.20
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• pp.97-105
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• 2002

Nowadays the gas utilities has been increasing constantly due to the expansion of the urban areas. The gas utility companies have adopted GIS technologies and been trying to computerize the management system for gas facilities to maintain up-to-dated information to forecast possible accidents and to minimize the casualties from the accidents. The major objective of this study is to develop a GIS-based gas accident management system which could facilitate early response and alternatives in the cases of the accidents. The system is able to provide the information for the pipes to be closed followed by selecting the location of the accident, and search all the relevant values connected to the location to provide all the information to minimize the casualties. In addition to that, the system can calculated the remaining amount of the gas in the pipes closed from the accident thereby providing more safer alternatives. In the future, more practical method needs to be made such as GPS-linked more integrated gas accident management system.

• Korean Journal of Construction Engineering and Management
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• v.19 no.6
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• pp.94-102
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• 2018

Recently, there is a growing need to review compliance with legal requirements to ensure fire safety as the number of fires caused by noncompliant fire safety facilities in high-rise buildings has increased. While there are a large number of apartment buildings in Korea, there is a lack of review on fire safety facilities' compliance with fire safety requirements. The reason for this lack of review despite apartment buildings causing deaths due to their structural features in the event of a fire, lies in the misinterpretation of legal provisions as the Building Act and the Fire Services Act are mixed up; a final inspection when fire safety facilities are unnecessarily installed or missing could result in significant losses in terms of finances and time. Therefore, this study developed a checklist that makes it possible to review mixed-up legal requirements for fire safety facilities simultaneously, and examined the importance and current level of each item through IPA (Importance Performance Analysis). Based on these results, this study intends to develop a manual that considers its applicability to construction practices and contribute to reducing construction companies' fire safety inspection risks.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.5
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• pp.473-480
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• 2011

Recently, the resizing algorithms based on the displacement participation factors have been developed for sizing members to satisfy stiffness criteria. It is proved that this resizing algorithms made for utilizing worker's stiffness design are practical and rational due to the simplicity and convenience of the method. The resizing algorithm can be practically and effectively applied to drift design of buildings. However, the researches on the change of inelastic behavior by the resizing algorithm has been insufficient. To identify the effect on the inelastic behavior of buildings by the resizing method, this study used the reinforced concrete shear wall-frame example. Through the application of the resizing method, the weights of shear wall in the lower class and the weights of columns and beams in the upper class increased respectively. And the initial stiffness of the building increased and the ductility of the buildings had similar with that of the initial structure.

• Journal of Radiation Protection and Research
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• v.14 no.2
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• pp.1-9
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• 1989

An analytic method for quantitative comparisions between the alternatives for radiation protection optimization is required to aid the decision making process. This paper introduces the dynamic Markov model to evaluate the effect of inservice inspection, testing, and repair activities of the plant on radiation protection. In the example to put the Markov model into practice, the steam generator inspection intervals which minimize expected cost and total exposure dose were determined using the data for Kori-2 unit and foreign plants. The results show that the effect of the radiation exposure on the steam generator inspection interval is determined by the cost rather than the radiation exposure. The Markov model used in the example can be applied easily to the domestic NPPs by replenishing the data and also can be used in evaluating the comparative priority between various alternatives for radiation protection optimization.

• Journal of Digital Convergence
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• v.16 no.7
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• pp.131-144
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• 2018

The purpose of this study is to empirically examine the unethical information sharing by information asymmetry. I will confirm the effect of ethical dilemma, unethical intention and behavior by the information asymmetry. A research method used the structural equations. The analysis showed causal relationship that ethical dilemma and unethical intention and behaviors by the information sharing. In particular, The ethical dilemma by position level showed different from the factor between dilemma and intention. As a result, the organization should manage differently ethical issue according to position level. The contribution in this study has expended an interpretation scope of broken windows theory from social science and explained a discriminative management of the ethical dilemma by position level from the practical view. A Future study should investigate an unethical behavior reduce by information security systems.