• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.2
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• pp.319-326
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• 2020

PRNGs(Pseudorandom number generators) are essential for generating encryption keys for to secure online communication. A bitstream generated by the PRNG must be generated at high speed to encrypt the big data effectively in a symmetric key cryptosystem and should ensure the randomness of the level to pass through the several statistical tests. CA(Cellular Automata) based PRNGs are known to be easy to implement in hardware and to have better randomness than LFSR based PRNGs. In this paper, we design PRNGs based on PMLCA(Programable Maximum Length CA) that can generate effective key sequences in symmetric key cryptosystem. The proposed PRNGs generate bit streams through nonlinear control method. First, we design a PRNG based on an (m,n)-cell PMLCA ℙ with a single complement vector that produces linear sequences with the long period and analyze the period and the generating polynomial of ℙ. Next, we design an (m,n)-cell PC-MLCA based PRNG with two complement vectors that have the same period as ℙ and generate nonlinear sequences, and analyze the location of outputting the nonlinear sequence.

• International Commerce and Information Review
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• v.14 no.4
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• pp.491-516
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• 2012

The purpose of this study is to research the situation of Technical Barriers of Trade(TBT) between Korea and China and analyze a pending issue such as a regular TBT notifications and specific trade concerns informed to WTO/TBT committee by Korea and China and seek the Countermeasures for Technical Barriers of Trade in Korea-China FTA. Generally, in case of a regular TBT notifications, "a protection of human health or safety" and "protection of the environment" are drawn a main articles from TBT committee data. And in case of a specific trade concerns, "international standard" and "transparency" are drawn a important factor from the said data. Henceforth those kinds of articles shall be an issuable matters for negotiation of Technical Barriers of Trade in Korea-China FTA. The results of the study indicate mainly that as Countermeasures of Korea for Technical Barriers of Trade in Korea-China FTA, Korean government level requires to withdraw an exclusive technical regulation of China and supports to improve Chinese technology for safety of products. Korean enterprises should develop products to meet an environment regulation and Korean government should support finance incentive, tax incentive to enterprises. Besides, regarding new international standard it is necessary for Korean side to dominate a relative regulation. First of all, it is important to secure a strength of capability and human resource for international standard activity. For improving a conveyance of notification information and transparency between Korea and China, it is efficient to establish a mutual direct network of notification.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.228-235
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• 2008

Terror for airplane, airport and passengers of the problems is being threat over the world. and since 9.11 terror of 2001 year, many countries have endeavored to prevent terror and have manipulate airport security part as important field. Especially, The U.S.A made Transportation security Administration in Homeland security adminstration and strongly execute for policies related anti-terror. many countries over the world enforce airport and airplane security facilities with science-technology contents. and with security exploitation for the passengers and freight security inspection level enforcement, many countries also make effort to interupt aviation terror threat. In this process, in the center of developed countries that need science-technology contents adaption, much budget and personals are invested and exploited a security inspection instrument and complimented of many facilities As a result, according to the development of science-technology, prevention of Terror have much developed. The contents using intelligence-communication technology inevitably needed on the goal of terror prevention and safty. From simple monitoring for the people who come in and out airport to boarding process and inspection for the freight, security inspection process for the passengers, bio information input, confirmation, of the level that there is no cases of adaption of contents, The reality have generalized of using contents. The study is going to research contents application situation.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.21-24
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• 2006

수소의 소규모 분산 생산 기술은 본격 적 인 수소 인프라가 도입되기 전에 연료전지 자동차의 수소 충전용이나 분산 발전형 연료전지의 수소 공급을 위해 필요하다. 생산 용량은 수소 기준으로 $20{\sim}100 Nm^3/hr$ 정도로 현재로선 천연가스의 수증기 개 질법이 가장 경제적인 공정으로 알려져 있다. 소규모 생산에 따른 열효율 저하를 줄이 기 위해 단위 공정들이 통합된 컴팩트 개질 시스템의 개발이 필요하다. 연료전지 자동차용 수소 인프라 조기 구축을 위하여 수소충전소 구축과 국산화 천연가스 수증기 개질기 개발을 병행하여 진행하였다. 수소 충전소 구축 부분은 충전소 부지 확보, 건물 건축, 각종 유틸리 티 설치의 토목 부분과 천연가스 개질형 수소 제조 유닛 설치, 수소 압축, 저장, 디스펜싱 시스템 설치를 포함하고 있으며 고압 설비에 대한 인허가 대응 및 안전대책 작업도 진행하였다. 구축된 수소충전소는 향후 연료전지 자동차 연계 실증 프로그램에 활용할 수 있다. 국산화 핵심 기술 개발을 위하여 열 및 시스템 통합 설계에 의 해 천연가스 수증기 개질기를 제작하고 내부 열교환 구조에 따른 개질기의 성능을 평가하였다. 개발된 개질기는 개질온도 $720^{\circ}C$, 수증기 대 카본 비 2.7의 운전조건에서 $23Nm^3/h$ 이상의 수소 생산이 가능하였으며 73% 이상의 개질 효율을 나타내었다. 개발된 천연가스 수증기 개질기는 향후 수소 정제용 PSA(Pressure Swing Adsorption) 시스템과 연계하여 수소충전소 국산화 엔지니어링 설계 패키지 개발의 핵심 기 술로 사용할 계획이다.시간 정도 운전한 후 시스템을 정지하였다 메탄 전환율과 일산화 탄소 농도, 열효율을 모니터링 하고 있으며, 현재까지 초기 성능을 그대로 유지하고 있다. 앞으로 일일시동-정지 운전 시험을 지속하면서 초기 시동 특성 및 부하 변동에 따른 응답 특성 개선, 그리고 연료전지와의 연계 운전을 실시할 예정이다 한다. 단위 전지 운전 온도 $130^{\circ}C$, 상대습도 37%의 운전 조건에서도 상당히 우수한 전지 성능을 보임에 따라 고온/저가습 조건에서 상용 Nafion 112 막보다 우수한 막 특성을 나타냄을 확인하였다.소/배후방사능비는 각각 $2.18{\pm}0.03,\;2.56{\pm}0.11,\;3.08{\pm}0.18,\;3.77{\pm}0.17,\;4.70{\pm}0.45$ 그리고 $5.59{\pm}0.40$이었고, $^{67}Ga$-citrate의 경우 2시간, 24시간, 48시간에 $3.06{\pm}0.84,\;4.12{\pm}0.54\;4.55{\pm}0.74 $이었다. 결론 : Transferrin에 $^{99m}Tc$을 이용한 방사성표지가 성공적으로 이루어졌고, $^{99m}Tc$-transferrin의 표지효율은 8시간까지 95% 이상의 안정된 방사성표지효율을 보였다. $^{99m}Tc$-transferrin을 이용한 감염영상을 성공적으로 얻을 수 있었으며, $^{67}Ga$-citrate 영상과 비교하여 더 빠른 시간 안에 우수한 영상을 얻을 수 있었다. 그러므로 $^{

• Journal of agriculture & life science
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• v.43 no.3
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• pp.63-75
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• 2009

The purpose of this study is to find out suggestions for government policy and expansion of consumption of environmental-friendly agricultural products(EFAP). For this purpose, we did research on purchasing pattern of EFAP and understanding of government environmental-friendly agricultural policy. First, the purchase of EFAP has been increased, because EFAP is safer. Consumers prefer department store because it is easier than any other marketing. Difficulties which consumers are facing when they purchase EFAP are price and credibility and small number of stores. Most favorable item is vegetable and the price of rice which consumers are willing to pay is really high. Second, not many consumers do recognize the label and system of EFAP. Third, most famous authentication institution agricultural products quality management service and other institutions are not recognized. Consumers recognize the certificate of origin. The government policy for safe food consumption is to intensify government supervision on foods. Suggestions from these results are as follow: First, the urgent problem to expand consumption of EFAP is credibility of EFAP. To make consumers trust EFAP, these are considered as useful solutions, i.e. recall, quality management service, standardization, and better quality. Second, government should be continue public relation, education and supervision of EFAP. Third, quality management should be continued. Not only central government but also local quality management institutions should continue quality management service. Last, local government should help farmers of EFAP to solve the difficulties of marketing.

• Journal of Internet Computing and Services
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• v.22 no.1
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• pp.31-39
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• 2021

Obtaining delivery addresses from calls is one of the most important processes in TV home shopping business. By automating this process, the operational efficiency of TV home shopping can be increased. In this paper, a method of recognizing and validating road name address, which is the address system of South Korea, from speech oriented text is proposed. The speech oriented text has three challenges. The first is that the numbers are represented in the form of pronunciation. The second is that the recorded address has noises that are made from repeated pronunciation of the same address, or unordered address. The third is that the readability of the resulted address. For resolving these problems, the proposed method enhances the existing address databases provided by the Korea Post and Ministry of the Interior and Safety. Various types of pronouncing address are added, and heuristic rules for dividing ambiguous pronunciations are employed. And the processed address is validated by checking the existence in the official address database. Even though, this proposed method is for the STT result of the address pronunciation, this also can be used for any 3^rd party services that need to validate road name address. The proposed method works robustly on noises such as positions change or omission of elements.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.750-757
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• 2018

The mechanically stabilized earth wall abutment is an earth structure using a mechanically stabilized earth wall and it uses in-extensional steel reinforcements having excellent friction performance. In order to analyze the pullout behavior of in-extensional steel reinforcements usually applied on the mechanically stabilized earth wall abutment, effects of stiffness and particle-size distributions of backfills and also horizontal spacings were considered in this study. As a result of parametric analyses, the highest pulling force acted on the uppermost reinforcement, and the stiffness and the particle-size distributions of the backfill significantly affected the pulling resistance of the reinforced soils. The internal friction angle of backfills should be at least 25 degrees, the coefficient uniformity factor should be at least 4, and the horizontal spacing of the uppermost steel reinforcement should be less than 25cm. Therefore, in order to secure the pullout resistance of the reinforced soil, it is necessary a properly spacing of reinforcement and more strict quality control for the backfill.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.397-404
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• 2019

When developing a weapon system, a T&E(Test and Evaluation) can be performed using M&S for the test items that cannot be evaluated in the real world. In this case, the VV&A activities are required to prove the credibility of M&S for the T&E. Recently, the use of M&S has been increasing as the R&D trends of weapon systems are becoming more advanced. Therefore, the VV&A activities are also increasing. The VV&A activities aim to verify, validate, and accredit that the simulation can represent a real system and ensure credibility regarding its purpose and intention of use. VV&A activities are divided into V&V and Accreditation. When performing VV&A in the ADD (Agency for Defense Development), the V&V activities are performed by a separate department of the ADD and the accreditation activities are performed in the DTAQ (Defense Agency for Technology and Quality). This paper proposes a V&V process for a T&E of M&S that has been performed in ADD. The process is used to verify and validate the documents and data generated during the development process according to the accreditation criteria, and provides objective data that can be used to judge whether the accreditation decision and acceptance criteria are met.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.477-484
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• 2019

As the residence time in the vehicle increases, the passenger desires a pleasant and stable riding environment in addition to the high driving performance of the vehicle. The windshield defrosting performance is one of the performance requirements that is essential for driver's safe driving. In order to improve the defrosting performance of the windshield of a vehicle, relevant elements such as the shape of the defrost nozzle should be appropriately designed. In this paper, CFD based numerical analysis is conducted to improve defrost performance of small electric vehicles. The defrost performance analysis was performed by changing the angle of the defrost nozzle and the guide vane that spray hot air to the windshield of the vehicle. Numerical simulation results show that the defrosting performance is best when the defrost nozzle angle is $70^{\circ}$ and the guide vane installation angle is $60^{\circ}$. Based on the analytical results, the defrosting experiment was performed by fabricating the defrost nozzle and the guide vane. As a result of the experiment, it is confirmed that the frost of windshield is removed by 80% within 20 minutes, and it is judged that the defrost performance satisfying the FVMSS 103 specification is secured.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.13 no.6
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• pp.556-561
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• 2020

The aging and declining agricultural population in the modern society requires improvement of the agricultural environment and is one of the representative problems. And since most of the work systems always require a transport work, the ratio of labor consumed in the transport work is very high. Accordingly, many types of transport vehicles are being developed and sold, and in the early days, most of them are powered transport vehicles using fossil fuels. However, it is paying attention to next-generation eco-friendly energy such as hydrogen, fuel cells, solar power, and bio due to the strengthening of international environmental regulations such as global warming and the Convention on Climate Change and the depletion of fossil fuels. Therefore, in this study, the ultimate goal is to develop an eco-friendly, easy-to-operate, safe agricultural electric vehicle that replaces fossil fuels. It was designed with a focus on controlling a wide range of vehicle speeds and securing stability of electric agricultural vehicles. Considering the performance and design, it is composed of a frame, a driving part, a steering part, and a controller system, and we are going to review and manufacture each part. It is believed that the manufactured electric vehicle for agriculture can be easily and conveniently operated in an agricultural society where young manpower is scarce, and can be helpful to the agricultural society through high efficiency.