• Journal of the Korean Society of Propulsion Engineers
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• v.24 no.2
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• pp.35-42
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• 2020

Recently the reusable launch vehicle is being a major trend in the worldwide space market, because a few commercial companies, especially SpaceX, are trying to cut down the launch price through developing and succeeding the reusable launch vehicles. However, there is still a big controversy about whether in view point of the launch cost which is more favorable between expendable and reusable. Therefore, a study and close examination is required for the launch cost in the early development phase of the reusable launch vehicle. In this study the sensitivity analysis is performed with respect to the major cost parameters which have great effects on the launch cost and price. The standard vehicle of this sensitivity analysis is the expendable vehicle having a payload 20 tons. The cost estimation relationships used in this calculation are referred from the commonly proven cost models such as TRANSCOST. The major cost parameters chosen in this study are as follows: development cost, production cost, refurbishment cost, and maximum reusable number.

• The Journal of Society for e-Business Studies
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• v.24 no.4
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• pp.31-48
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• 2019

To survive in the trend of the fourth industrial revolution, companies are putting a lot of attention and effort into personalization services using the latest technologies such as big data, artificial intelligence and the Internet of Things, while entrusting third parties to handle personal information on the grounds of work efficiency, expertise and cost reduction. In such an environment, consignors need to check trustees on a more effective and reasonable basis to ensure personal information safety for trustees. This study used AHP techniques to derive the importance and priority of each item of "Personal Information Safety Assurance Measures" for financial companies and trustees, and objectively compared and analyzed differences in perceptions of importance between financial institutions and trustees. Based on this, the company recognizes the difference between self-inspection of financial institutions and inspection of trustees and presents policy grounds and implications for applying differentiated inspection standards that reflect the weights appropriate for the purpose.

• Journal of Digital Contents Society
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• v.6 no.1
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• pp.19-24
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• 2005

Mobile service is able to offer the elastic service to anyone regardless of the place and the tin. With this characteristics, the ubiquitous service could be also provided even to the place which the access was limited with the existing line service, which could improve the mutual connection and could result in the service extension Mobile communication companies, which realized the limit of sale only by telephone conversation, have made an effort to develop wireless internet with concentration as its alternation. Especially concentrating their effort both to the development of distinctive and various contents and to tin development of system for mobile service such as the mobile banking, mobile game and etc., they have done their best to secure the number of the people using the wireless internet. This study is to propose the electronic account system based on the mobile as a case study of contents production for such a mobile service. This system has its advantage to perform the financial management immediately when the income and outcome happen without limitation of the time and space. The information could be stored, searched and modified by using of the mobile phone for this system was made up for the weak point of the financial management for wired internet.

• Journal of Convergence for Information Technology
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• v.10 no.6
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• pp.35-40
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• 2020

As we enter the society of the future, efforts to increase healthy living are a major area of concern for modern people. In particular, the development of technology for a healthy life that combines ICT technology with a competitive healthcare industry environment is becoming the next growth engine. Therefore, in this paper, artificial intelligence-based data analysis of the examination results was applied in the health examination process. Through this, a research was conducted to build a knowledge base modeling that can improve the reliability of the overall judgment. To this end, an algorithm was designed through deep learning analysis to calculate and verify the test result index. Then, the modeling that provides comprehensive examination information through judgment knowledge was studied. Through the application of the proposed modeling, it is possible to analyze and utilize big data on national health, so it can be expected to reduce medical expenses and increase health.

• Proceedings of the KWS Conference
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• 2010.05a
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• pp.95-95
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• 2010

자동차 산업에서 차체를 성형하는 프레스 금형 산업은 꾸준히 증가하고 있는 자동차 생산대수와 함께 성장해가고 있으며, 자동차 산업의 국제 경쟁이 심해지고 소비자들의 요구가 다양해짐에 따라 신제품 개발주기에 발맞추어 금형의 제작에도 단납기 및 비용절감을 위한 노력과 제품의 품질 향상을 위해 신기술, 신공법이 적용되고 있다. 한편 자동차 차체를 제작하는 프레스 금형가공은 박판소재를 원하는 형상으로 제작하는 공정으로써, 프레스의 상 하 운동을 이용하여 강판을 성형한다. 이러한 금형의 형태는 곧 자동차 차체 제품의 형태를 완성하므로 제품을 성형하는 도중에 금형과 소재의 마찰에 의해 금형의 마모나 마멸이 발생하여 제품의 품질을 저하시킬 우려가 있다. 따라서 금형의 내마모성 및 수명을 향상시키기 위한 방안들 중 표면경화처리가 행해지고 있으며, 그중 공정 속도가 빠르고 국부적인 열처리가 가능한 레이저 표면처리 방법이 많은 관심을 받고 있다. 본 연구에서는 이러한 금형의 성질을 향상시키기 위해 고출력 다이오드 레이저를 이용하여 프레스 금형공정 중 드로잉(drawing) 공정에의 적용을 위한 표면경화처리를 실시하였다. 최대출력 4.0kW의 다이오드 레이저를 사용하였으며, 6축 외팔보 로봇에 열처리용 광학계를 장착하여 열처리를 실시하였다. 또한 광학계 부근에는 적외선 온도센서가 부착되어있어 열처리시 시험편의 표면온도를 실시간으로 측정할 수 있도록 구성되어져있다. 시험편은 금형재료용 구상흑연 주철인 FCD550 소재를 사용하였으며, 공정변수에 따른 열처리 특성을 파악하고, 그 경화특성을 평가하였다. 실험 결과, FCD550 소재의 표면 열처리시 레이저 출력 3.5kW, 빔 이송속도 3mm/sec에서 최적의 열처리 특성을 나타내었으며, 이때의 최고 경도는 930Hv을 나타내며 모재에 비해 경도가 3배 정도 상승하는 우수한 경화특성을 보였다.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.9
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• pp.32-45
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• 2013

Globally, intelligent vehicles and telematics research and development through the integration of IT technology in the vehicle are significant increasing. Real-time data communication for intelligent transportation system (ITS) is very important. It collects real-time data from the vehicle and provides the information collected from ITS center. We propose an effective and secure communication scheme for these communication procedures. In particular, our proposed SIP-based MVPN reduces signaling cost and has many advantages in security aspects. In addition, our proposed scheme performs the mobility management applying NEMO (Network Mobility) for the communication between the vehicles. In other words, we propose an ITS communication mechanism of SIP-based mobile VPN and V2V NEMO. Finally, our performance analysis show that the ITS of SIP-based MVPN is significantly reducing the handoff signaling cost.

• 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 Korea Society of Industrial Information Systems
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• v.11 no.5
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• pp.53-61
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• 2006

We propose public-oriented e-Marketplace framework construction that activates efficiently transaction of non-metal industrial resources through the case of Mineralland. The firms of Non-metal industrial resources domain have low information level and weak capital structure. So public enterprise has to construct e-marketplace to trade using exact market information. This framework consists of five domains-contents, commerces, communities, collaboration and electronic authentication. To draw this framework, we review many web-sites and literatures about B2B of industrial resources domain. In addition, this study provides practical implications and guidelines for activating public oriented e-Marketplace of non metal industrial resources.

• Journal of the Korea Society of Computer and Information
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• v.20 no.5
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• pp.91-98
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• 2015

In this paper, we introduce PMS's main function and main effect which implemented medium and large scale software development project site, and we propose importance and improvement nacessity of PMS implementation. PMS's main functions are developed based on best practices which CMMI model and PMBOK. Also, each PMS has specialized unique function according to it's target industry area or related I.T solutions which has infra dependency. The effectiveness of PMS implementation on project site is seperated two types, one is qualitative effect, the other quantitative effect. Representative qualitative effects are improvement of enterprise's image and competency. Also representative quantitative effect is reduction of project management cost as a financial effect. As far as project size is increase, PMS's needs and necessariness will be increase, so we need to improve PMS;s function according to project management's global trend and software customer's requisition.

• Journal of Sericultural and Entomological Science
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• v.8
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• pp.27-34
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• 1968

상수의 엽면적은 상엽의 수획량 즉 수량과 높은 상관관계가 있고 그의 간이측정법은 매우 의의 깊은 일이므로 상전에서 생체대로 엽면적을 측정할 수 있도록 간이측정법을 고안하였다. 우리나리 상수의 주요품종인 개량서반, 일지뢰, 노상 그리고 수원 제4호의 4개품종을 재료로 절위별로, 지조별로 엽면적과 엽장, 최대엽폭과의 관계를 조사 실험하였으며 공시 엽수는 개량서반 741문, 일지뢰 853문, 노상 507문, 수원제4호 441문, 도합 2,542문이었다. 5개열엽으로 엽형이 비슷한 개량서반과 일지뢰의 2개품종의 엽면적은 (엽장$\times$최대엽폭)$\times$0,643, 단엽인 노상과 수원제4호의 2개품종의 엽면적은 (엽장$\times$최대엽폭)$\times$0,735에 의해서 구할 수 있음을 알았다. 즉 개량서반과 일지뢰는 엽장에 최대엽폭을 곱한 적에 계수 0.634를 곱함으로써 전처리엽에서 planimeter에 의한 엽면적과 높은 상관관계를 보였고 이때의 상관계수의 평균을 개량서반에 있어서는 r=0.931, 일지뢰에 있어서는 r=0.960이었다. 노상과 수원상4호는 엽장에 최대엽폭을 곱한 적에 계수 0.735를 곱함으로써 전처리엽에서 planimeter에 의한 엽면적과 또한 높은 상관관계를 보였고 이때의 상관계수의 평균을 개량서반에 있어서는 r=0.931, 일지뢰에 있어서는 r=0.960이었다. 노상과 수원상 4호는 엽장에 최대엽폭을 곱한 적에 계수 0.735를 곱함으로써 전처리엽에서 planimeter에 의한 엽면적과 또한 높은 상관관계를 보였고 이 때의 상관계수 r의 평균을 노상에 있어서는 r=0.999, 수원상 4호에 있어서는 r=0.996이었다. 이 방법에 의하면 시간과 노력을 크게 절감시킬 수 있을 뿐만 아니라 생체대로 쉽게 엽면적을 구할 수 있는 이점이 있다.