• 경영과학
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• 제33권1호
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• pp.49-58
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• 2016

Focusing on the drastic increase of smart devices, machine generated data expansion is a general phenomenon in network services and IoT (Internet of Things). Especially, built-in multi sensors in a smart device are used for collection of user status and moving data. Combining the internal sensor data and environmental information, we can determine landmarks that decide a pedestrian's locations. We use an ANOVA method to analyze data acquired from multi sensors and propose a landmark classification algorithm. We expect that the proposed algorithm can achieve higher accuracy of indoor-outdoor positioning system for pedestrians.

• 기술사
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• 제45권1호
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• pp.45-48
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• 2012

이번 일본 북동해안에서 발생한 지진해일에 대한 원인과 영향을 살펴보고 방재대책과 방재대응 시스템의 필요성을 고찰해 보았다. 기술적으로 지진발생을 예측할 수는 없으나 발생한 해일이 해안에 도달하는 시간은 예측이 가능하므로 재난에 대비하기 위한 예보경보시스템 구축이 필요한데 이를 위해 지진해일 감시를 위한 관측시스템 구축과 국가간 긴밀한 협조체계가 필요하다. 또한 방재시설, 방조수문, 육갑, 항구방파제, 하천제방 등 방재구조물의 종류와 효과를 살펴보았다. 우리나라의 경우는 무엇보다 지진해일에 의한 재해정보도의 제작, 보급이 필요하며 해안에 거주하는 주민을 대상으로 지속적인 교육, 훈련을 통해 유사시 인명과 재산의 피해를 최소화하는 노력이 시급한 것으로 판단된다.

• 한국유기농업학회지
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• 제10권2호
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• pp.1-28
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• 2002

Regarding the dangers to soil, water and air, which come from current agricultural application measures for nitrogen, a sectoral approach for a non-polluting liquid manure utilization cannot be used any longer. Slurry was not any longer considered as a tiresome waste produced of animal husbandry, but as a valuable fertilizer. The goal of the largest possible utilization of slurry on the farm was and still is in the foreground, An Integrated system approach has to be found. leading to a drastic improvement of nutrient utilization and hence to a considerably reduced nutrient use. This can only be expected, if the organic manure can be applicated at times, when losses through leaching and volatilization can be minimized. The necessary investments for such concepts can clearly be reduced through cooperation.

• 대한의용생체공학회:의공학회지
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• 제39권6호
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• pp.268-277
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• 2018

With drastic change in the market and technology of medical devices, a comparative analysis is necessary in advanced systems internationally in order to prepare domestically applicable plans for improvement in classification and differential grade management for items of medical devices. This research examines and analyzes the differences of definition and legal systems of medical devices among Korea, United States, EU, Japan and China, and investigates classification and grading system of each country to identify disadvantages of classification and grading structures for medical device in Korea. This research suggests ways to supplement the disadvantages of domestic classification and grading system of medical devices, and elicits differential management plans for medical devices.

• 현장농수산연구지
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• 제25권2호
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• pp.20-29
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• 2023

This study suggests integration scheme for agricultural governance of South and North Korea after unification by comparing and analyzing their current agricultural governance, assuming drastic changes of economic system in integration process after unification. The North Korea's critical food shortage will force reformation of its agricultural governance to be the top priority in integration process after unification. The agricultural governance of South and North Korea has comparable structures. However, the North Korea's agricultural governance is extremely inefficient because it is established for political purposes. The integration scheme suggested includes expansion of Rural Development Administration, integration of research institutes, establishment of branch of Korea National University of Agriculture and Fisheries, transformation of existing North Korea's organization into South Korea's system and preparation of training programs for North Korea's officials.

• 정보처리학회논문지A
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• 제18A권3호
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• pp.93-98
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• 2011

최근 배터리로 동작하는 임베디드 시스템의 사용이 급격히 증가하고 있지만, 현재 배터리 기술의 발전 속도는 임베디드 시스템의 전력 사용량의 증가를 따라가지 못하여, 장시간 사용을 위해서는 배터리의 크기가 커져야 하는 단점이 있다. 내장형 시스템에서 소모하는 전력량은 시스템을 구성하는 하드웨어와 시스템을 구동하는 소프트웨어에 의해 결정된다. 그러나 하드웨어적으로 저전력을 지원하더라도 운영체제 등 소프트웨어 수준에서 이를 활용하지 못하면 절전 효과를 극대화할 수 없다. 따라서 본 논문에서는 모바일 임베디드 시스템 환경에서 멀티미디어 애플리케이션 구동시 BET(Break Even Time)기반 태스크 분할을 이용하여 소비 전력을 감소시키는 스케줄링 기법을 제안한다.

• 전기학회논문지
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• 제67권1호
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• pp.96-102
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• 2018

For efficient operating strategy of electric power system, forecasting of daily peak electric load is an important but difficult problem. Therefore a daily peak electric load forecasting system using a neural network and fuzzy system is presented in this paper. First, original peak load data is interpolated in order to overcome the shortage of data for effective prediction. Next, the prediction of peak load using these interpolated data as input is performed in parallel by a neural network predictor and a fuzzy predictor. The neural network predictor shows better performance at drastic change of peak load, while the fuzzy predictor yields better prediction results in gradual changes. Finally, the superior one of two predictors is selected by the rules based on rough sets at every prediction time. To verify the effectiveness of the proposed method, the computer simulation is performed on peak load data in 2015 provided by KPX.

• 디지털산업정보학회논문지
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• 제9권4호
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• pp.59-67
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• 2013

Compared to the conventional Hardware-oriented base stations, Software Defined Radio (SDR)-based base station provides various advantages especially in flexibility and expandability. It enables the multimode capability required in 4th-generation (4G) environment which aims at a convergence network of various kinds of communication standards. However, since a single base station processes all data required in various multiple waveforms, the SDR base station faces a problem of data processing speed. In this paper, we propose a new concept of SDR base station system which adopts a parallel processing technology of clustering environment. We implemented a WiMAX system with SDR concept which adopts the Message Passing Interface (MPI) technology which enables the speed-up operations. In order to maximize the efficiency of parallel processing in signal processing, we analyze how the algorithm at each of modules is related to data to be processed. Through the implemented system, we show a drastic improvement in operation time due to parallel processing using the proposed MPI technology. In addition, we demonstrate a feasibility of SDR system for 4G or even beyond-4G as well.

• 한국군사과학기술학회지
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• 제23권6호
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• pp.602-608
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• 2020

PRAIRIE(Propeller Air Induced Emission) system is a kind of underwater radiated noise suppression systems to reduce the probability of the identification or classification of our warship's acoustic signature by an enemy ship. It is effective in case of strong cavitation events. This is because air bubbles emitted from the PRAIRIE system mitigate drastic collapses of the cavity bubbles that can generate an intense shock wave. However, when the PRAIRIE system is operated in a non or weak cavitation condition, it might increase the total level of underwater radiated noise and induce the acoustic signatures. Therefore, this paper presents the trial results on ventilation control of PRAIRIE to find a more efficient operation depend on the cavitation condition. Then, we show a variation of the amplitude modulation characteristics according to ventilation control.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2004년도 추계학술대회 논문집
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• pp.375-381
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• 2004

Recently, the evolution in production techniques (e.g. high-speed milling) and the complex shapes involved in modem production design has been increasingly popular. The key to the achievement is a drastic improvement of the dynamic behavior of the machine tool axes used in production machinery. The more complex these tool paths the higher the speed and acceleration requirements. But it is very difficult to reach the target for high speed machine tool because of the limitations of servo system and motion control system. However the direct drive design of machine tool axes, which is based on linear motors and which recently appeared on the market, is a viable candidate to meet the ever increasing demands, because of these advantages such as no backlash, less friction, more mechanical simplicity and very higher acceleration and velocity comparing to the traditional system. This paper focused on the performance tests of the high speed horizontal machine tool based on linear motor. Especially, dynamic characteristics were investigated through circular test and circular form machining test is carried out considering many important parameter. Therefore these several experiments is used to be evaluated the model for prediction of circular motion error and circular machined error.