• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.10a
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• pp.414-416
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• 2010

WiBro network technologies developed mainly by Korea are one of very promising 4G technologies. WiBro has been standardized as international standard called Mobile WiMAX, and has been deployed in many countries. Emergency Services are infrastructural servicesa and very essential to induce subscribers from other types of networks. This paper propose a network architecture for supporting emergency services for mobile VoIP services in WiBro networks. The proposed architecture is based on WMF's architecture for internationa compatibilities, and reflects national considerations on interfacing PSAP for domestic compatibilities.

• Informatization Policy
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• v.18 no.3
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• pp.88-107
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• 2011

This paper proposes a prepaid system promotion policy for the 3G(WCDMA) MVNO with regard to the newly included paragraphs 3, 4 and 5 of Article 32 (User Protection) and Article 38 (Provision of Wholesale Telecommunications Services) of the Telecommunication Business Act, which was revised on March 22, 2010. As of June 2011, there are only a few prepaid system subscribers to the mobile communications service due to various limitations, including prepay, interconnection, carrier selection, the MVNO policy, and number portability. However, overseas communications service regulatory agencies and service providers are increasingly presenting policies and strategies for mobile prepaid plans, in order to accommodate the various customer demands that are increasing the use of smart phones and data. This paper advances various proposals concerning promotion of the prepaid system by the 3G MVNO under the current Telecommunication Business Act, including separation of the prepaid data system and the mobile network; introduction of a monthly fixed-rate hybrid prepaid system, a top-up system and USIM system; introduction of mobile network carrier selection; differentiated retail discounts between prepaid and post-paid prices; revision of the retail discount policy for wholesale provision; increase in the number of mandatory service providers; and in-depth consideration of the introduction of a number portability policy for the prepaid and post-paid systems.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.3
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• pp.239-256
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• 2017

In the process of site selection for a radioactive waste disposal, site characterization must be carried out to obtain input parameters to assess the safety and feasibility of deep geological repository. In this paper, methodologies of site characterization for radioactive waste disposal in Korea were suggested based on foreign cases of site characterization. The IAEA recommends that site characterization for radioactive waste disposal should be performed through stepwise processes, in which the site characterization period is divided into preliminary and detailed stages, in sequence. This methodology was followed by several foreign countries for their geological disposal programs. General properties related to geological environments were obtained at the preliminary site characterization stage; more detailed site characteristics were investigated during the detailed site characterization stage. The results of investigation of geology, hydro-geology, geochemistry, rock mechanics, solute transport and thermal properties at a site have to be combined and constructed in the form of a site descriptive model. Based on this site descriptive model, the site characteristics can be evaluated to assess suitability of site for radioactive waste disposal. According to foreign site characterization cases, 7 or 8 years are expected to be needed for site characterization; however, the time required may increase if the no proper national strategy is provided.

• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.697-703
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• 2022

Due to the recent economic downturn caused by Covid-19 and the unstable international situation, many investors are choosing the derivatives market as a means of investment. However, the derivatives market has a greater risk than the stock market, and research on the market of market participants is insufficient. Recently, with the development of artificial intelligence, machine learning has been widely used in the derivatives market. In this paper, reinforcement learning, one of the machine learning techniques, is applied to analyze the scalping technique that trades futures in minutes. The data set consists of 21 attributes using the closing price, moving average line, and Bollinger band indicators of 1 minute and 3 minute data for 6 months by selecting 4 products among futures products traded at trading firm. In the experiment, DNN artificial neural network model and three reinforcement learning algorithms, namely, DQN (Deep Q-Network), A2C (Advantage Actor Critic), and A3C (Asynchronous A2C) were used, and they were trained and verified through learning data set and test data set. For scalping, the agent chooses one of the actions of buying and selling, and the ratio of the portfolio value according to the action result is rewarded. Experiment results show that the energy sector products such as Heating Oil and Crude Oil yield relatively high cumulative returns compared to the index sector products such as Mini Russell 2000 and Hang Seng Index.

• The Korean Journal of Air & Space Law and Policy
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• v.31 no.1
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• pp.63-97
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• 2016

Ago the passenger who using a wheelchair was denied boarding from the airline. The ACT ON THE PROHIBITION OF DISCRIMINATION AGAINST DISABLED PERSONS prohibits discriminatory treatment of persons with disabilities in transportation. But there are situations that limits the movement on persons with reduced mobility. The international community promote to protect disabled persons and persons with reduced mobility against discrimination and to provide them with assistance when travelling by air. According to news report, the governing Council of the International Civil Aviation Organization (ICAO) has established new global core principles on air transport consumer protection. The principles cover three phases of a customer's experience: before, during and after travel, and will now be considered by ICAO's 191 Member States when they develop or review their applicable national regimes. The international community are recognizing that passengers can benefit from a competitive air transport sector, which offers more choice in fare-service trade-offs and which may encourage carriers to improve their offerings, passengers, including those with disabilities, can also benefit from consumer protection regimes. In accordance with these we will also be provided to regulations that can prevent and protect the air passenger. In this paper analyze the regulations of the international air passenger rights, point out the lack of policy.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.4
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• pp.222-234
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• 2021

Airborne-pests can be introduced into Korea from overseas areas by wind, which can cause considerable damage to major crops. Meteorological models have been used to estimate the wind trajectories of airborne insects. The objective of this study is to analyze the effect of input settings on the prediction of areas where airborne pests arrive by wind. The wind trajectories were predicted using the HYbrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. The HYSPLIT model was used to track the wind dispersal path of particles under the assumption that brown plant hopper (Nilaparvata lugens) was introduced into Korea from sites where the pest was reported in China. Meteorological input data including instantaneous and average wind speed were generated using meso-scale numerical weather model outputs for the domain where China, Korea, and Japan were included. In addition, the calculation time intervals were set to 1, 30, and 60 minutes for the wind trajectory calculation during early June in 2019 and 2020. It was found that the use of instantaneous and average wind speed data resulted in a considerably large difference between the arrival areas of airborne pests. In contrast, the spatial distribution of arrival areas had a relatively high degree of similarity when the time intervals were set to be 1 minute. Furthermore, these dispersal patterns predicted using the instantaneous wind speed were similar to the regions where the given pest was observed in Korea. These results suggest that the impact assessment of input settings on wind trajectory prediction would be needed to improve the reliability of an approach to predict regions where airborne-pest could be introduced.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.12
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• pp.8791-8799
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• 2015

In this paper, One-way car-sharing System represents the verification system consider events in revenue effects. Revenue which the time and distance represented the graph, compare one-way vehicle relocate car-sharing system which proven in existing international papers with one-way vehicle relocate car-sharing system consider the event currently in the Korea. Especially, The maximum profit according to the distance and time were assessed through multiple linear regression analysis, and there are probable maximum loss allow for the maximum loss. The company suggested using the event as a discount coupon to customers through various marketing strategies, and then focused on increasing customer demand. So, Correlation analysis to determine the maximum revenue of the actual travel distance and time were carried out through Non-linear Regression.

• Food Industry
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• s.20
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• pp.88-91
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• 1974

유나이티드 브랜드(United Brands Co)는 약칭 유니프루로 통해온, 바나나왕국 유나이티드 프루우츠(United Fruit Co)의 후신. 4년전인 70년 식품업계의 복합기업으로 주목을 끌었던 AMK Corp.와 합병, 새출발한 다각경영 기업이다. 현재는 식육관련 제품이, 전체매상의 60$\%$로, 주종을 이루고 있으나, 바나나 생산판매로서는 여전히 세계 제일의 왕국으로 군림하고 있다. 73년도 매상은 마침내 20억대를 넘어선 20억6천616만달러, 미국 대기업 순위 74위를 마크하고 있다. 그러나 수익률은 50년대이후 줄곧 1$\%$안팍의 낮은 수준(73년 순익 2천5백36만달러)에서 헤어나지 못하고 있다. 이런 역경 속에서도 유나이티드 브랜드는 무릎을 꿇을 줄 모르는 끈질긴 기업으로 통한다. 그것은 맹수와 독사가 우글거리는 황무지를 개척해 온, 유니프루의 강인한 개척근성을 이어 받았기 때문이다.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06d
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• pp.22-24
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• 2006

유선 환경의 초고속 인터넷 서비스는 일반적으로 PC와 같은 고정형 단말을 대상으로 한다. 휴대폰이나 네비게이션용 GPS 단말 같은 이동 단말은 비교적 정확하게 단말의 위치를 찾을 수 있어 이를 활용한 응용 서비스가 확대되는 추세이다. 유선 인터넷 단말의 경우 IP주소의 할당 내역을 바탕으로 비교적 넓은 영역의 지역 정보를 찾아서 이용하는 Geo Targeting이 미국 등 해외에서 활성화 되고 있으나 국내에서는 IP에 대한 지역정보를 얻을 수 있는 적절한 방법이 없어 관련 서비스가 크게 활성화되고 있지 못하다. 본 논문에서는 유선 인터넷 환경 하의 Geo Targeting 구현에 대해 설명하고 이를 활용한 응용 서비스를 소개한다.

• Journal of the KSME
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• v.32 no.6
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• pp.554-562
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• 1992

수치제어(NC : numerical control) 기술은 공장자동화를 위한 중요 기술이다. 우리 산업현장에 공장 자동화가 확장되면서 NC 공작기계, 산업용 로봇, 삼차원 좌표측정기 등의 사용이 매우 증 가되고 있다. 이러한 수치제어용 기계에서는 자동 위치제어를 위하여 길이변위와 회전각도 감 지용 센서인 NC 엔코더가 매우 중요한 부품이다. NC 엔코더에는 선형 엔코더(NC-스케일)와 회전 엔코더가 있으며, 각각 직선운동과 회전운동을 제어하기 위해서 필요한 자동화 부품이다. 그림 1에서는 CNC 위치제어 시스템에서 정확한 위치로 이동을 목표로하여 서보 제어할 때 기 계축의 위치를 감지하는 센서가 NC 엔코더임을 보여주고 있다. 선형 엔코더는 직선운동의 변 위를 감지하며 NC-스케일 이라고도 말한다. 우리나라에서는 아직 엔코더 제작기술을 개발하지 못하여 전량수입에 의존하고 있다. 이러한 NC 엔코더의 수요는 해외 시장뿐만 아니라 국내시 장에서도 급격히 증가되고 있으며 국산화 개발이 시급하다. 이 글에서는 엔코더의 종류별 작동 원리를 설명하고 또한 NC-스케일 제조기술을 개발하기 위하여 실험하였던 결과를 정리하고자 한다.