• 제목/요약/키워드: Won Bang

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에너지 수집 기능이 있는 인지 무선 시스템의 협력 스펙트럼 센싱 기법 (Cooperative Spectrum Sensing for Cognitive Radio Systems with Energy Harvesting Capability)

  • 박성수;이석원;방극준;홍대식
    • 대한전자공학회논문지TC
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    • 제49권3호
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    • pp.8-13
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    • 2012
  • 본 논문에서는 에너지 수집(energy harvesting) 기능이 있는 무선 센서 노드(sensor node)들이 인지 무선 시스템의 스펙트럼 센싱 신뢰성 및 정확도를 높이기 위하여 협력 스펙트럼 센싱을 수행하는 무선 센서 네트워크를 제안한다. 각 센서 노드들이 태양광, 풍력 등으로부터 에너지를 자체적으로 수집하여 전원으로 이용할 때, 수집되는 에너지의 양에 따라 적응적으로 스펙트럼 센싱을 수행하고, 그 결과를 융합 센터(fusion center)로 전송하는 적응적 스펙트럼 센싱 기법을 제안한다. 모의실험을 통해 무선 센서 네트워크를 구성하는 센서 노드의 수와 수집되는 에너지의 통계적인 특성에 따라 스펙트럼 센싱의 성능이 어떻게 달라지는지 보이고, 센서 노드의 에너지 검출기에 사용되는 표본의 개수를 조절함으로써 융합 센터에서 오검출 확률을 최소화할 수 있음을 보여준다.

서울지역 일부 국민학교의 음용수 이용에 관한 연구 (A study on the drinking water for some primary school in Seoul)

  • 이원묘;방형애
    • 대한영양사협회학술지
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    • 제1권1호
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    • pp.31-42
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    • 1995
  • The aims of this study are to enhance the students' knowledge of the drinking water and its reliability by investigating drinking water situation and the degree of students' knowledge on the drinking water. The results are as follows 1. Status and drinking behavior about school drinking water (1) 97.53% of the schools are using the tap water as the resource of drinking water (2) 46 schools are in possession of water tank and 18 schools of them are using the water tank as the resource of drinking water. The cleaning and sanitization of the tank are carried out once in a year with hypochloronatrium by the low-level officials, nurse teachers, and dietitian. 2. The degree of students' knowledge about drinking water (i) This survey represent that students favor the spring water best and think the tap water worst for drinking. (2) 83% of the students think that the tap water is polluted and these conception are formed mostly by the mass communication. 80% of boys and 90% of girls answered they don't drink plain tap water.

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수두차를 이용한 수저퇴적물 제거장치 개발에 관한 연구 (Study on the Development of Removing System for Waterbed Sediment by the Difference of Water Head)

  • 이영길;손충렬;정우철;유진원;정광열;김강신;김방열
    • 대한조선학회논문집
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    • 제45권1호
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    • pp.101-107
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    • 2008
  • According to the existing research result on the seabed organic sediment, pollutants from the land and the sea contaminate the coastal water and sediment on the seabed. To tackle this problem, we need to dredge organic sediment. In the present paper, the development of removing system of seabed sediment by the difference of water head is researched by experimental method. For the validation of the decompression system, computations for validation are carried out for sediment removing equipment. The performance of inhalation equipment is analysed by some model tests.

세종 의존명사/대명사/수사 전자사전의 정보표상 구조 (The Representational Structure of Lexical Informations of Korean non-autonomous nouns in the Sejong Electronic Dictionary)

  • 방성원;호정은;김종인
    • 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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    • 한국정보과학회언어공학연구회 2001년도 제13회 한글 및 한국어 정보처리 학술대회
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    • pp.341-347
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    • 2001
  • 세종전자사전이 궁극적으로 범용전자사전을 지향한다는 점에 비추어 볼 때, 텍스트 자동 분석과 생성, 정보 검색 및 자동 번역 등에 활용될 데이터베이스로서의 전자사전은 자연 언어 어휘의 내적 구조와 기능방식에 관한 정보들, 가령 음운 통사 의미 화용적 가치와 실현 조건 등에 관한 정보들을 체계적이고도 정교하게 담고 있어야만 한다. 의존명사, 대명사, 수사 범주에 속하는 언어 단위들은 단일 명사와 구별되는 어휘 통사적 속성들을 지니며, 사전의 기술 구조에는 그 정보 값들을 체계적으로 명시화할 수 있는 정보 항목과 표상 구조가 설정되어야 한다. 가령 의존명사처럼 통사 의미적 자율성을 지니지 않는 언어 요소의 경우, 어휘 관계 정보보다는 인접하는 여타 언어 단위들과의 호응관계나 결합제약 조건들이 더 중요한 정보일 수 있다. 본 사전이 체언사전의 하위사전으로 별도로 구축되는 것은 단일어 사전에서 그러한 정보들을 효과적으로 표상하기 어렵기 때문이다. 그러나 본 사전은 실제적으로는 체언사전에 통합되어 운영된다는 점에서 이중적 지위를 누린다고 하겠다.

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Methodology for Estimating the Number of Failed Fuel Rods in Operating PWRs Using Diffusion and Kinetic Models

  • Lee, Sang-Kyu;Tak, Nam-IL;Kim, Yang-Seok;Chun, Moon-Hyun;Sung, Ki-Bang;Kang, Duck-Won
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1996년도 추계학술발표회논문집(1)
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    • pp.97-102
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    • 1996
  • A methodology for estimating the number of failed fuel rods bused on the primary coolant activity in operating PWRs has been developed. This method deals with both the diffusion and the kinetic models. In case of small or medium cladding failures, the diffusion model which can consider different sizes of failure is used, whereas for large cladding failures the kinetic model is used. From the kinetic model, the release-to-birth rate ratio (R/B) is represented as a linear function of the number of failed fuel rods. This has been done by expressing the escape rate coefficient in terms of the slope of log(R/B) versus $log\;{\lambda}$. The present method has been applied to the cases of 26 cycles of several nuclear power plants for which ultrasonic testings were performed. The results show that the present method gives better predictions than the existing computer codes such as IODYNE and CADE.

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전 상악골 절제술 후 양경 유리 견갑 골-피부 피판을 이용한 재건 3례 (Total Maxillectomy Defect Reconstruction Using Bipedicled Scapular Osteocutaneous Free Flap: 3 Cases)

  • 김정민;하범준;문구현;현원석;방사익;오갑성
    • Archives of Reconstructive Microsurgery
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    • 제12권1호
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    • pp.30-37
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    • 2003
  • We used bipedicled scapular osteocutaneous free flap for total maxillectomy defect reconstruction in 3 cases of malignant maxillary tumor. We elevated two flaps of the skin paddle and the bone flap with one common pedicle - the subscapular artery - which was devided to the angular branch of the thoracodorsal artery and the circumflex scapular artery to reconstruct the nasal cavity, the palate and the zygoma. The angle between the two flaps was free enough so that we could transfer the two flaps through a single microanastomosis. After the operation, patients could swallow and pronounce well, and the wound contracture was minimal so that we could get aesthetically good result.

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사료 부원료 하역과정에서 발생하는 비산먼지의 여과특성 (Filtration Characteristics of the Fugitive Dust Emitting from Animal Feedstuff Handling)

  • 방진철;한세현;정용원
    • 한국대기환경학회지
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    • 제22권2호
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    • pp.191-199
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    • 2006
  • Animal feedstuff handling is one of the major fugitive dust sources in the port of Incheon. For the effective control of fugitive dusts emitting from the port of Incheon, dust control facilities with bag filter systems should be designed properly considering the characteristic of the fugitive dusts including those from animal feedstuffs. The ultimate goal of this study is thus to develop the optimum fugitive dust control system which will be applicable for the renovation of the port. As the first step to achieve this longstanding goal, filtration characteristics of soybean shell, the largest dust sources in the port, were investigated with the specially designed filter testing apparatus for this study. The variables tested for the experiments included filter materials, dust concentrations, relative humidities, and filtration velocities. Also, the filtration characteristics of the other animal feedstuffs such as sunflower seed shell, tapioca, and palm shell were investigated to determine $K_2$ as a function of filtration velocity. The information on $K_2$ will be used to design the optimum bag filter systems for animal feedstuffs handling in the port.

신뢰성 있는 기동 항적 추적을 위한 다중 레이더 융합 알고리즘 (A Multi Radar Fusion Algorithm for Reliable Maneuvering Target Tracking)

  • 조태환;이창호;김진욱;원인수;조윤현;박효달;최상방
    • 한국항행학회논문지
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    • 제15권4호
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    • pp.487-494
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    • 2011
  • 레이더를 이용한 항적 융합 알고리즘은 반드시 필요하며, 이를 통해서 높은 신뢰성을 확보할 수 있다. 본 논문에서는 칼만필터 보다 성능이 좋다고 알려진 IMM(Interacting Multiple Model) 필터를 이용하여 다중 레이더 융합 알고리즘을 제안하였다. 분산형 융합 방식을 적용하였고, 부필터 3개, 주필터 1개를 이용하였다. 성능분석은 등속운동, 가속운동, 선회 등 항공기 기동을 묘사한 가상의 레이더 데이터를 이용하여 분석하였다. 성능분석 결과, 항공기가 기동하는 구간에서도 좋은 추적 성능을 보였다.

Spontaneous Intracranial Hemorrhage in Children: Analysis of Clinical Characteristics

  • Lee, Bang-Hoon;Song, Shi-Hun;Choi, Seung-Won;Kim, Seon-Hwan;Koh, Hyeon-Song;Youm, Jin-Young
    • Journal of Korean Neurosurgical Society
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    • 제37권1호
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    • pp.34-38
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    • 2005
  • Objective: Spontaneous intracranial hemorrhage in children is not common and very different compared to adults. We analyze the etiology, hemorrhagic type, clinical features, and outcome of spontaneous intracranial hemorrhage in children. Methods: Twenty-nine patients under 17years of age with nontraumatic intracranial hemorrhage were analyzed retrospectively. Neonates were excepted. We reviewed their medical records in regard to their age, symptoms, radiologic findings, treatment, and prognosis. Results: Among 29 patients, there were 17boys and 12girls. The average age was 10.2years. The most common presenting symptom was mental deterioration, and the most common cause was arteriovenous malformation. Spontaneous intracranial hemorrhage in children showed a better prognosis than in adults. Conclusion: Spontaneous intracranial hemorrhage in children resulted mainly from vascular malformation and the prognosis is relatively good. More careful follow-up studies and active management are needed for better outcomes.

Keyhole Approach and Neuroendoscopy for Cerebral Aneurysms

  • Cho, Won-Sang;Kim, Jeong Eun;Kang, Hyun-Seung;Son, Young-Je;Bang, Jae Seung;Oh, Chang Wan
    • Journal of Korean Neurosurgical Society
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    • 제60권3호
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    • pp.275-281
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    • 2017
  • Treating diseases in the field of neurosurgery has progressed concomitantly with technical advances. Here, as a surgical armamentarium for the treatment of cerebral aneurysms, the history and present status of the keyhole approach and the use of neuroendoscopy are reviewed, including our clinical data. The major significance of keyhole approach is to expose an essential space toward a target, and to minimize brain exposure and retraction. Among several kinds of keyhole approaches, representative keyhole approaches for anterior circulation aneurysms include superciliary and lateral supraorbital, frontolateral, mini-pterional and mini-interhemispheric approaches. Because only a fixed and limited approach angle toward a target is permitted via the keyhole, however, specialized surgical devices and preoperative planning are very important. Neuroendoscopy has helped to widen the indications of keyhole approaches because it can supply illumination and visualization of structures beyond the straight line of microscopic view. In addition, endoscopic indocyanine green fluorescence angiography is useful to detect and correct any compromise of the perforators and parent arteries, and incomplete clipping. The authors think that keyhole approach and neuroendoscopy are just an intermediate step and robotic neurosurgery would be realized in the near future.