• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.91-91
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• 1999

광소자 기술은 정보 전달 및 저장 기술의 지속적인 증가 요구에 따라 발전을 거듭하여 왔다. 특히 광통신 및 저장 기술에서 광원으로 사용되는 레이저 다이오드는 안정되면서 쉽게 제작할 수 있어야 한다. 이온 주입 방법은 반도체 공정에서 광범위하게 사용되는 공정이며 이미 소자측면에서 안정성이 확보되었다고 볼 수 있으나 대부분 메모리 등의 실리콘 반도체에서 이용되어 왔다. 최근에는 화합물 반도체 분야에서도 적용하는 예가 증가되고 있으나 광원으로 사용되는 레이저 다이오드의 경우는 우수한 품질의 반도체 층이 요구되며 따라서 damage가 큰 이온 주입 방법을 이용한 연구는 아직 많이 이루어져 있지 않다. 본 연구에서는 레이저 다이오드 구조의 성장측에 국부적으로 Fe 이온을 주입하여 도파로를 형성하여 광을 구속하여 도파시키는 동시에 전기적으로도 도파로 부분으로만 다이오드가 형성되도록 하고자 한다. 먼저 p층의 전기적 절연에 필요한 조건을 확보하기 위하여 CBE를 사용하여 Fe가 doping 된 SI-InP wafer 위에 p-InP (Be:5x1017 cm-3)층을 1.2$mu extrm{m}$ 성장한 후 ohmic 층으로 p-InGaAs (Be:1x1019 cm-3)을 0.1$\mu\textrm{m}$ 성장한 시료에 고에너지 이온 주입 장치를 사용하여 Fe 이온을 1MeV, 1.6meV의 에너지에 각각 1x1014cm-2, 2x1014cm-2 의 dose로 전면에 implant 하였다. 이 시료를 tube furnace에서 500, 600, $700^{\circ}C$각각 10분씩 annealing 한 후 재성장을 확인하기 위하여 DCXRD을 측정하였다. 그림 1은 DCXRD rocking curve로 annealing 하기 전 후의 In rich에서 side peak의 감소를 확인 할 수 있었는데 이는 damage가 어느 정도 복구되었음을 의미한다. 또한 절연 특성을 확인하기 위하여 ohmic metal을 증착하여 Hall 효과를 측정하였다. 그림 2에 보이는 것과 같이 annealing 온도가 증가함에 따라 면저항이 크게 증가함을 볼 수 있으며 이온 주입하기 전의 시료에 비해 104 이상의 저항을 갖을 수 있다. 향후 이러한 결과를 바탕으로 1.55$\mu\textrm{m}$ LD 구조에서 발진 특성을 관찰할 계획이다.

• The Journal of Korean Association of Computer Education
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• v.14 no.6
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• pp.1-10
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• 2011

Since IT technology grow rapidly, our ethic of consciousness has become big issue with adverse effect. Many scholar has discussed and tired to solve this problem, but it is still helpless to fix. Therefor in this paper, author will not suggest the solution, but will present model list of adverse effects and cases to prevent accidents. The model list of adverse effects, what author will present is about media addiction, harmful content, cyber-violence, right infringement, cyber terror and decision obstacle. This model list is made by primary and secondary survey. This model will show adverse effect of present day, but also will show future adverse effects that can be prevent. Through out this paper, this model list could use for education plan.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.12 s.115
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• pp.1164-1171
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• 2006

In this paper, a simple and nonlinear MMSE detector is derived from the conventional linear MMSE detector to improve the system performance in turbo processing MIMO system and a new turbo processing MIMO system with nonlinear MMSE detector and Gaussian approximation is proposed. In turbo coded turbo processing MIMO system, the proposed system of M=N=4 performs about 0.5 dB better than the conventional system and the proposed system of M=N=8 performs about 0.4 dB better than conventional system at 1 % FER. In addition, the average number of outer iterations of proposed system shows lower than that of conventional system. This is caused by the fact that the nonlinear MMSE detector of proposed system decides soft-outputs of coded bits based on the observation of received signals, so that it can reduce the uncertainty region in estimating the coded bits.

• Proceedings of the Korea Contents Association Conference
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• 2005.11a
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• pp.210-218
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• 2005

Recently, customers can select various service providers using number portability according to given select options such as quality of service and fare organization. Therefore it is possible that subscriber maintenance and quality competition are converted to fare competition which is real competition concept. However, it is time that we need number portability between $2G{\rightarrow}3G$ for activating 3G services because some important issues are closed such as domestic number portability, WiBro service provider selection. In this paper, we proposed applying method and necessity of $2G{\rightarrow}3G$ number portability Also, we analyzed $2G{\rightarrow}3G$ number portability examples of domestic and foreign countries and domestic market situation about abstract of 3G mobile communication service and number portability introduction between $2G{\rightarrow}3G$ for 3G service activation appearing newly in this research.

• Proceedings of the Korea Contents Association Conference
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• 2005.05a
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• pp.273-279
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• 2005

It is activated a virtual university(digital university) without limitation time and space that the diffusion of internet, the rapid development of information and communicative technologies, web-technology. It is great importance of school-site to support various and qualitative education services, to cut social education spending, to strengthen national competitiveness with breed expert. Many people who are in universities are putting a school-site to the test. So we need study and analysis it to build up a virtual-study-space efficiently on web. This thesis is supposed to help in school-site design to make it reduce errors and save time and efforts. First, it suggests most general design pattern by analysis visual elements using HTML Tag. Second, it suggests a guide-line and a specific of design to use convenience through research on web-design problem and finding out user's favor.

• Journal of Distribution Science
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• v.7 no.1
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• pp.35-53
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• 2009

Sees the market where home appliance and network equipment, the communication service enterprises are new recently the home network market of the most which has an interest in the home network is being activated the newly-built high-class apartment in the center. The company building leads because not being option of the case last customer of newly-built market and must do a business . marketing. So newly-built market the demand grasp which is individual leads sale activation with difficult and that to creates a benefit there is a limit judges and axis market in the object hereafter demand at even the popular house the function to prepare in being magnified is simple and there is a possibility of saying that a more effort is demanded in supply style video phone market opening up where the price is cheap. Saw with like this reason from, analyzes the concept and a market trend of the video phone, grasps distribution channel forms and A/S handling systems and there is the goal finds the video phone sale revitalization plan which is suitable in all market.

• Journal of Advanced Navigation Technology
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• v.18 no.4
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• pp.353-358
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• 2014

In the past, security on control system was guaranteed by isolation of control system networks from external networks. However as devices of the control systems became more various and interaction between the devices became necessary, effective management system for such network emerged and this triggered connection between control system networks and external system networks. This made management of control system easier but also made control system exposed to various cyber attack threats, Therefore researches on appending security measures on each protocols are in progress. This paper focused on DNP(distributed network protocol)3 protocol which is used for communication between control center and substations. It describes characteristics of DNP3 protocol and research on adding security elements to the protocol. It also analyzed known vulnerabilities of DNP3 protocol and proposed data mining methodology for detecting such vulnerabilities.

• Journal of The Korean Association of Information Education
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• v.7 no.3
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• pp.285-298
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• 2003

According to the operation guide book concerning the educations of Information Communication, Art for Primary and Middle school issued by Ministry of Education, Korea, 2001, it revealed many things as to an Spread Sheet's paradigm, that is, as to an useful program in Science, Practical course, Moral, Physical education and Society. However it can be said that the existing Spread Sheet is more or less unconvenience to use for pupils. Because most of pupils generally feel constrained to the functional formula and also when a complicated menu of Spread Sheet would be made the most of it. Moreover, from a certain point of view, it is somewhat too difficult to use the program as they feel intuitionally taking a look at it. This very thesis in order to support a part of probability and statistics for pupils were observed sincerely.

• Journal of Navigation and Port Research
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• v.33 no.6
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• pp.387-393
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• 2009

In this paper, a 3-D simulator was developed to estimate visually the performance of propelling and integrated control system of the underwater cleaning robot. Based on the dynamics analysis of the UCR, the 3-D model of the UCR was used in the simulator in which position and velocity are included Also, an input and control system using a joystick was developed, and the simulator was applied to the input and control of the simulator. Moreover, an integrated navigation control system was designed, and its performance was validated by a way-point simulator including a PI-based fuzzy control law.

• The KIPS Transactions:PartD
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• v.9D no.6
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• pp.1083-1090
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• 2002

The software development methodology has not caught up with the rapid change of information technology. Most of the software development projects use structural methodology or information engineering methodology. If established software development methodologies don't reflect technologies applied to the project, the project may be performed ineffectively. This paper describes a model in which we can apply a new information technology to an already existed structural methodology or information engineering methodology. This model uses the technique of the divide and conquer that software development life cycle is divided into phases, each phase is divided into viewpoint- areas and the software development processes of a new information technology are applied to each small area. By using the design phase this paper shows application example, in which I applied web-based development processes to CS@RoadMap Methodology of KCC Information & Communication, a system provider in Korea. The CS@RoadMap Methodology reflecting the Web technology, Web@RoadMap Methodology, has been applied to the public-domain projects.