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Spent Fuel and Waste Management Activities For the Cleanout of the 105F Fuel Storage Basin at HANFORD

  • Morton, Mark-R.;Rodovsky, Tomas J.;Lee, Sun-Kee
    • 한국방사성폐기물학회:학술대회논문집
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    • 한국방사성폐기물학회 2007년도 학술논문요약집
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    • pp.190-191
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    • 2007
  • Cleanout of the F Reactor Fuel Storage Basin (FSB) is an element of the FSB decontamination and decommissioning (D&D) and is required to complete interim safe storage (ISS) of the F Reactor. Following reactor shutdown and in preparation for a deactivation layaway action in 1970, the water level in the FReactor FSB was reduced to approximately 0.6 m (2 ft) over t]to floor. Basin components and other miscellaneous items were left or placed in the FSB. The item placement was performed with a sense of finality, and no attempt was made to place the items in an orderly manner. The F Reactor FSB was then filled to grade level with 6(20of local surface material (essentially a fine sand). The reactor FSB backfill cleanout has the potential of having to remove spent nuclear fuel (SNF) that may have been left unintentionally. Based on previous cleanout of six water-filled FSBs with similar designs (i.e., the B, C, D, and DR FSBs in the 1980's), it was estimated that up to five SNF elements could be discovered in the F FSB (I). In reality about 17 full SNF elements were found in the excavation. This paper covers the technical and programmatic challenges of performing this decommissioning effort with some of the controls used for SNF management. The paper also will highlight how many various technologies were married into a complete package to address the issue at hand and show how no one tools could complete the job, but combined, good progress is being made.

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알레르기 화분의 특성과 최근 소아에서 잡초류 화분의 감작률 증가 (Characteristics of allergic pollens and the recent increase of sensitization rate to weed pollen in childhood in Korea)

  • 오재원
    • Clinical and Experimental Pediatrics
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    • 제51권4호
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    • pp.355-361
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    • 2008
  • Pollen is very important causing factor for allergy such as allergic rhinitis, allergic conjunctivitis, and asthma, and pollen allergy has a remarkable clinical impact all over Korea. The main pollination period covers about half the year, from spring to autumn, and the distribution of airborne pollen taxa of allergological interest is related to pollen season dynamics. Korean academy of pediatric allergy and respiratory diseases (KAPARD) has evaluated the pollen characteristics and nationwide pollen count for over 10 years since 1997. Airborne particles carrying allergens were collected daily from nationwide 8 stations (Seoul, Guri, Cheongju, Daegu, Kwangju, Busan, Kangneung, and Jeju) by using 7 days-Burkard sampler (Burkard Manufacturing Co Ltd, Hertfordshire, UK) in South Korea (July 1, 1997-June 30, 2007). They were counted and recorded along with the meteorological factors daily. Tree pollen is a major airborne allergen in spring, grass is most common in summer, and weed pollen is major pollen in autumn in Korea. There has two peak seasons for pollen allergy, as summer and autumn. There is some evidence suggesting that the prevalence of allergic diseases in Korea has been on the increase in the past decade. However, recent findings of the phase I and II studies of the international Study of Asthma and Allergies in Childhood (ISAAC) study showed the absence of increases or little changes in prevalence of asthma symptoms and diagnosis rates in Korea, whereas the prevalence of allergic rhinitis and atopic dermatitis were increased. We reported the evidence that sensitization rate to weed pollen has been increased yearly since 1997 in childhood. Climate change and air pollution must be the major causing factors for the increase of pollen counts and sensitization rate to pollen. Climate change makes the plants earlier pollination and persisting pollination longer. In conclusion, data on pollen count and structure in the last few years, the pathogenetic role of pollen and the interaction between pollen and air pollutants with climate change gave new insights into the mechanism of respiratory allergic diseases in Korea.

Sweet Bee Venom Pharmacopuncture May be Effective for Treating Sexual Dysfunction

  • Lee, Pavel;Yu, Junsang
    • 대한약침학회지
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    • 제17권3호
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    • pp.70-73
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    • 2014
  • Sexual dysfunction (SD) is a health problem which occurs during any phase of the sexual response cycle that keeps the individual or couple from experiencing satisfaction from the sexual activity. SD covers a wide variety of symptoms like in men, erectile dysfunction and premature or delayed ejaculation, in women, spasms of the vagina and pain with sexual intercourse, in both sexes, sexual desire and response. And pharmacopuncture, i.e. injection of subclinical doses of drugs, mostly herb medicine, in acupoints, has been adopted with successful results. This case report showed the effect of bee venom on SD. A 51-year-old male patient with SD, who had a past history of taking Western medication to treat his SD and who had previously undergone surgery on his lower back due to a herniated disc, received treatments using pharmacopuncture of sweet bee venom (SBV) at Gwanwon (CV4), Hoeeum (CV1), Sinsu (BL23), and Gihaesu (BL24) for 20 days. Objectively, the patient showed improvement on most items on the International Index for Erectile Dysfunction (IIEF) like 28 to 29 out of perfect score 30 for erectile function, 10 to 10 out of perfect score 10 for orgasmic function, 6 to 8 out of perfect score 10 for sexual desire, 10 to 13 out of perfect score 15 for satisfaction with intercourse, and 6 to 8 out of perfect score 10 for overall satisfaction; subjectively, his words, the tone of his voice and the look of confidence in his eyes all indicated improvement. Among the variety of effects of SBV pharmacopuncture, urogenital problems such as SD may be health problems that pharmacopuncture can treat effectively.

공시품질이 주가급락에 미치는 영향: 불성실공시 지정기업을 대상으로 (The Impact of Disclosure Quality on Crash Risk: Focusing on Unfaithful Disclosure Firms)

  • 유혜영
    • 산경연구논집
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    • 제10권6호
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    • pp.51-58
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    • 2019
  • Purpose - Prior studies reported that the opacity of information caused stock price crash. If managers fail to disclose unfavorable information about the firm over a long period of time, the stock price is overvalued compared to its original value. If the accumulated information reaches a critical point and spreads quickly to the market, the stock price plunges. Information management by management's disclosure policy can cause information uncertainty, which will lead to a plunge in stock prices in the future. Thus, this study aims at examining the impact of disclosure quality on crash risk by focusing on the unfaithful disclosure firms. Research design, data, and methodology - This study covers firms listed on KOSPI and KOSDAQ from 2004 to 2013. Firms excluded from the sample are non-December firms, capital-eroding firms, and financial firms. The financial data used in the research was extracted from the KIS-Value and TS2000 database. Unfaithful disclosure firm designation data was collected from the Korea Exchange's electronic disclosure system (kind.krx.co.kr). Stock crash is measured as a dummy variable that equals one if a firm experiences at least one crash week over the fiscal year, and zero otherwise. Results - Empirical results as to the relation between unfaithful disclosure corporation designation and stock price crashes are as follows: There was a significant positive association between unfaithful disclosure corporation designation and stock price crash. This result supports the hypothesis that firms that have previously exhibited unfaithful disclosure behavior are more likely to suffer stock price plunges due to information asymmetry. Second, stock price crashes due to unfaithful disclosures are more likely to occur in Chaebol firms. Conclusions - While previous studies used estimates as a proxy for information opacity, this study used an objective measure such as unfaithful disclosure corporation designation. The designation by Korea Exchange is an objective evidence that the firm attempted to conceal and distort information in the previous year. The results of this study suggest that capital market investors need to investigate firms' disclosure behaviors.

고분자 유기실리콘 계면활성제의 개발 동향 (Trend on Development of Polymeric Organosilicone Surfactants)

  • 랑문정
    • 한국응용과학기술학회지
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    • 제32권3호
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    • pp.546-567
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    • 2015
  • 실리콘계 계면활성제는 소수성 유기실리콘 그룹에 하나 또는 그이상의 친수성 극성그룹이 결합되어 있다. 반면에 탄화수소 계면활성제의 소수성 그룹은 탄화수소이다, 실리콘 계면활성제는 낮은 계면장력, 윤활성, 퍼짐성, 발수성, 열 안정성, 화학적 안정성 때문에 폴리우레탄 폼을 시작으로 건설재료, 화장품, 페인트잉크, 농약 등 많은 산업분야에 사용되고 있다. 다양한 응용분야에서의 요구사항을 반영하기 위한 다양한 기능을 가진 폭 넓은 화학구조를 가진 실리콘 계면활성제들이 필요하다. 본 총설에서는 소수성 폴리실록산 중추로서의 폴리디메틸실록산과 반응성 폴리실록산의 성질과 합성방법, 반응성 폴리실록산을 친수성 그룹과 결합시키는 규소수소화반응 같은 주요 반응방법, 그리고 폴리에테르, 이온성, 카보하드레이트 타입 같은 주요 고분자 실록산 계면활성제들의 합성방법을 논의한다.

LARGE-SCALE VERSUS EDDY EFFECTS CONTROLLING THE INTERANNUAL VARIATION OF MIXED LAYER TEMPERATURE OVER THE NINO3 REGION

  • Kim, Seung-Bum;Lee, Tong;Fukumori, Ichiro
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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    • pp.21-24
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    • 2006
  • Processes controlling the interannual variation of mixed layer temperature (MLT) averaged over the NINO3 domain ($150-90^{\circ}W$, $5^{\circ}N-5^{\circ}S$) are studied using an ocean data assimilation product that covers the period of 1993 to 2003. Advective tendencies are estimated here as the temperature fluxes through the domain's boundaries, with the boundary temperature referenced to the domain-averaged temperature to remove the dependence on temperature scale. The overall balance is such that surface heat flux opposes the MLT change but horizontal advection and subsurface processes assist the change. The zonal advective tendency is caused primarily by large-scale advection of warm-pool water through the western boundary of the domain. The meridional advective tendency is contributed mostly by Ekman current advecting large-scale temperature anomalies though the southern boundary of the domain. Unlike many previous studies, we explicitly evaluate the subsurface processes that consist of vertical mixing and entrainment. In particular, a rigorous method to estimate entrainment allows an exact budget closure. The vertical mixing across the mixed layer (ML) base has a contribution in phase with the MLT change. The entrainment tendency due to temporal change in ML depth is negligible comparing to other subsurface processes. The entrainment tendency by vertical advection across the ML base is dominated by large-scale changes in wind-driven upwelling and temperature of upwelling water. Tropical instability waves (TIWs) result in smaller-scale vertical advection that warms the domain during La Ni? cooling events. When the advective tendencies are evaluated by spatially averaging the conventional local advective tendencies of temperature, the apparent effects of currents with spatial scales smaller than the domain (such as TIWs) become very important as they redistribute heat within the NINO3 domain. However, such internal redistribution of heat does not represent external processes that control the domain-averaged MLT.

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수면무호흡증을 관리를 위한 스마트 베개 시스템의 설계 (Design of Smart Pillow System for Managing Sleep Apnea)

  • 이종찬
    • 한국융합학회논문지
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    • 제11권1호
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    • pp.33-39
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    • 2020
  • 전문의에 의해 옆으로 누워도 편안함을 주는 등 수면과학과 인체공학을 고려한 베개가 개발되었다. 이 베개는 천연라텍스를 소재로 하여 일정시간 지나면 복원력이 떨어지는 점을 개선하였다. 이 베개에 새로운 아이디어가 추가되었는데 베개는 당연이 수면을 위해 사용되는 것이나, 건강관리를 위한 부가적인 기능을 여기에 추가할 수도 있지 않을까 하는 것이었다. 여기서 건강관리는 심각한 질병과 연관된 것으로 알려진 수면무호흡증을 대상으로 한다. 본 논문은 압력센서와 음성센서를 이용해 정보를 구하고 이 정보로부터 질병에 관한 이상증상을 파악하여 전문의에 의뢰하는 종합적인 서비스를 설계함을 목적으로 한다. 그리고 이 시스템의 성공 가능성을 확인하기 위한 기초적인 설계와 구현을 다룬다. 이 설계를 바탕으로 얻어진 정보를 DB화하고 전문의와의 상담을 위한 서버 시스템을 완성하여 수면 무호흡증을 위한 보조건강기기로 역할을 담당할 수 있도록 업그레이드하는 방안에 대해 살펴본다.

입력지연을 갖는 이산시간 선형시스템을 위한 예측기 피드백 제어기의 강인성 해석 (Robustness Analysis of Predictor Feedback Controller for Discrete-Time Linear Systems with Input Delays)

  • 최준영
    • 전기전자학회논문지
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    • 제23권4호
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    • pp.1265-1272
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    • 2019
  • 본 논문에서는 상수 입력지연을 갖는 이산시간 선형시스템을 위한 기존의 예측기 피드백 제어기의 구조적 모델 불확실성에 대한 강인성을 해석한다. 상수 입력지연을 1차 PdE (Partial difference Equation)로 모델링하여 입력지연을 PdE 상태변수로 대체하고 백스테핑 변환을 적용하여 목표 시스템을 구축한다. 목표 시스템을 기반으로 전체 상태변수를 포함하는 명시적 리아푸노프 함수를 구성하여 안정성이 유지되는 구조적 모델 불확실성의 최대 크기의 존재를 증명하고 예측기 피드백 제어기의 강인성을 확립한다. 모의실험을 통하여 모델 불확실성이 존재하는 경우에도 닫힌 루프 시스템의 안정성이 유지되는 것을 예증하고 예측기 피드백 제어기의 강인성을 검증한다.

닫힌 공간에서의 광역배관 누출 감시를 위한 배열센서를 이용한 누설 위치 검출 (Leakage Localization with an Acoustic Array that Covers a Wide Area for Pipeline Leakage Monitoring in a Closed Space)

  • 박춘수;전종훈;박진호
    • 비파괴검사학회지
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    • 제33권5호
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    • pp.422-429
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    • 2013
  • 배관에서 발생한 문제는 비단 배관의 손상뿐만 아니라, 배관과 연결된 주요기기 혹은 시스템 전체의 작동에도 영향을 주기 때문에 이상 유무에 대한 감시가 필요하다. 특히, 원전 2차계통의 배관들은 안전상의 이유로 넓은 실내 공간 내에 복잡하게 배치되어 있다. 넓은 영역에 배치되어 있는 전체 배관의 누출 상태 감시를 하기 위해서는 센서 배열을 이용한 원격지에서의 누출 감시 방법이 효율적인데, 닫힌 공간 내에 있기 때문에 발생하는 반사파의 영향을 고려하여야 한다. 따라서 복잡한 실내 공간에서 발생하는 반사파의 특성과 빔형성법에의 영향을 수학적으로 살펴보았다. 그리고 반사파의 영향을 줄이는 공간평균방법을 적용한 빔형성법을 사용하여 광역배관의 구조 건전성 감시가 가능한 방법에 대해 제안하고, 이를 모사한 전산 모의실험과 누출 배관의 축소 모형 장치를 이용한 실험을 통하여 그 적용성을 검증하였다.

스키코스 계획기준에 관한 연구-가평스키장을 사례로 (A Study on the Planning Parameter of Ski Course-A Case of GaPyung Ski Resort)

  • 이시영
    • 자연과학논문집
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    • 제13권1호
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    • pp.97-111
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    • 2003
  • 본 연구는 가평스키장계획을 통해 스키슬로프의 계획기준을 살펴보는데 있다. 본 대상지는 경기도 가평군 하천리에 위치하고 있고 면적은 $1,594,001m^2$이다. 가평스키장의 설계목표는 본 부지에 가장 적합하고 경쟁력있는 스키코스를 설계하는데 있다. 설계과정은 먼저 부지조사와 분석, 설계프로그램의 지형분석의 종합, 슬로프계획, 타스키장과의 비교를 통한 특화계획 등을 포함한다. 본 스키장은 총 슬로프연장 8,738m이고 5기의 리프트와 10개의 스키슬로프로 조성되며 2개의 중급자, 3개의 중상급자, 4개의 상급자, 1개의 최상급자코스로 구성된다. 가평스키장은 모글이나 하프파이프같은 특화된 스키장으로서 상급자와 보더전용의 스키장으로 개발전략을 수립한다.

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