• 제목/요약/키워드: Reasonable

검색결과 9,267건 처리시간 0.037초

Low Outliers를 고려한 홍수빈도분석에 관한 연구 (A study on the Flood Frequency Analyzed in Consideration of Low Outliers.)

  • 이순혁;홍성표;박명근
    • 한국농공학회지
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    • 제30권4호
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    • pp.62-70
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    • 1988
  • This study was conducted to solve the problems for the unsuitable parameters and the uncertainty of design flood can be appeared by low outliers were inclined to the lower part from the trend of the balance of the data. Derivation of reasonable design flood was attempted finally by modification of low outliers with analysis of flood frequency by means of Log Pearson Type Ill distribution. Three subwatersheds were selected as studying basins with the annual maximum series including low outliers along Geum River basin. The results through this study were analyzed and summarized as follows. 1. Log Pearson Type In distribution was confirmed as a reasonable one by X$^2$ goodness of fit test at Gong Ju, Gyu Am, og Cheon watershed along Geum River basin. 2. Probable flood flows for each watershed were derivated by flood frequency curve with outliers. 3. Weighted skew coefficient for each watershed was calculated for the evaluation of freq- uency factor which is needed for the modification of low outlier. 4. It was confirrned that adjusted frequency curve has a lower tendency than that of deletion of low outlier in common at all watersheds. 5. Final probable flood flows were derivated by modification with evaluation of modified basic statistics for three watersheds. 6. In comparison with a frequency curve with modification and one with outlier, The former has a higher probable flood flow within three years of return periods than that of the latter, and vice versa over three years of return periods.

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시뮬레이션 기반의 컨테이너터미널 생산성측정 전략 (The Simulation-based Strategy of Measuring Productivities in the Container Terminal)

  • 박병인
    • 한국항만경제학회지
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    • 제18권1호
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    • pp.43-60
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    • 2002
  • Apart from the DEA method, the traditional measuring systems of container terminal productivities generally bring to light the partial productive efficiencies, because they evaluate only the productivity of each individual facility. However, these methods do not play roles of the reasonable productivity measures to compare and evaluate the efficiencies of terminals to meet the requirement of terminal customers like as shipping lines, shippers, etc. with the cutthroat competition in container handling market. As the suppliers of service, the terminals struggle to cope with the needs of buyers' markets due to the lack of suitable criteria to measure the efficiencies. Therefore, this paper uses the simulation approach to reveal which strategies enhance the productivities through the container terminal analysis. An additional intent of this paper is to build the active strategies to present what the experimental indexes like as norm-time exactness ratio, norm-time excess ratio, etc. compare between terminals to measure the total productivities for the age of global supply chain management. However, the experimental productivity indexes presented in this paper require a validation of the exact usefulness, by consideration from all angles in the future, and a development to more reasonable measuring method/indexes for the container terminal productivities.

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해상화물운송에 있어서 선박의 감항성(勘航性)과 인과관계(因果關係)에 관한 법리적(法理的) 접근(接近) (A Juridical Approach to Causal Relations between Ocean Freight Shipping and Seaworthiness of Vessel)

  • 박창식;김청열
    • 한국항만경제학회지
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    • 제22권2호
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    • pp.83-108
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    • 2006
  • Regarding the ocean carrier's responsibility for damage indemnification, both his or her duty of care and reason of legal exemption have been considered important. The International Convention for the Unification of Certain Rules relating to Bills of Lading also provides that the ocean carrier indemnifies for the loss or damage of freight on the basis of the principle of liability with fault. In other words, the carrier assumes responsibility only for the loss or damage of freight which is under his or her control and whose safety must be carefully maintained by him or her. The carrier's duty of care which is required for freight safety in accordance with the convention is associated with two themes, seaworthiness of vessel and freight itself. To make ocean freight shipping effective necessities the seaworthiness of the ship that will conduct the shipping service under its responsibility. This will ultimately lead to making the service impressive to the shipper as freight owner. Thus the purpose of this study is to contribute to more reasonable shipping by the shipowner or the carrier who needs to ensure seaworthiness of vessel, and prevent unseaworthiness that may be incurred in accordance with freight characteristics. For the purpose, this paper reviewed the meaning of seaworthiness of vessel through a juridical approach to its causal relationship with ocean freight shipping.

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Hybrid Scaling Based Dynamic Time Warping for Detection of Low-rate TCP Attacks

  • 소원호;유경민;김영천
    • 한국통신학회논문지
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    • 제33권7B호
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    • pp.592-600
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    • 2008
  • In this paper, a Hybrid Scaling based DTW (HS-DTW) mechanism is proposed for detection of periodic shrew TCP attacks. A low-rate TCP attack which is a type of shrew DoS (Denial of Service) attacks, was reported recently, but it is difficult to detect the attack using previous flooding DoS detection mechanisms. A pattern matching method with DTW (Dynamic Time Warping) as a type of defense mechanisms was shown to be reasonable method of detecting and defending against a periodic low-rate TCP attack in an input traffic link. This method, however, has the problem that a legitimate link may be misidentified as an attack link, if the threshold of the DTW value is not reasonable. In order to effectively discriminate between attack traffic and legitimate traffic, the difference between their DTW values should be large as possible. To increase the difference, we analyze a critical problem with a previous algorithm and introduce a scaling method that increases the difference between DTW values. Four kinds of scaling methods are considered and the standard deviation of the sampling data is adopted. We can select an appropriate scaling scheme according to the standard deviation of an input signal. This is why the HS-DTW increases the difference between DTW values of legitimate and attack traffic. The result is that the determination of the threshold value for discrimination is easier and the probability of mistaking legitimate traffic for an attack is dramatically reduced.

국가경쟁력 강화를 위한 SOC 확보 방안 (A Study to Secure Reasonable Transportation Infrastructure Stock for Improving National Competitiveness in Korea)

  • 박용석
    • 한국건설관리학회:학술대회논문집
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    • 한국건설관리학회 2008년도 정기학술발표대회 논문집
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    • pp.38-43
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    • 2008
  • 한 국가의 SOC 시설 보유량은 공공서비스의 공급능력을 보여주는 지표로 활용되고 있으며, 국가경쟁력의 원천이 되고 있다. 한국은 SOC 시설이 충분하다는 판단하에 '03년 이후 SOC 투자를 점차 축소하고 있다. 하지만 SOC 투자 축소는 기존 SOC 공사의 공기지연이 발생하고 있으며, 향후에는 국가경쟁력을 저해할 가능성을 갖고 있다. 따라서 충분한 수준의 SOC 투자는 지속되어야 한다. 이를 위해 우선 교통시설특별회계를 최소한 국가기간교통망계획의 계획기간인 '19년까지 연장할 필요가 있다. 또한 민간투자사업을 효과적으로 활용하고, SOC 투자를 완공위주의 집중투자를 해야 한다.

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The Influence of the Debt Ratio and Enterprise Performance of Joint Stock Companies of Vietnam National Coal and Mineral Industries Holding Corp.

  • HOANG, Thi Thuy;HOANG, Lien Thi;PHI, Thi KimThu;NGUYEN, Minh Thu;PHAN, Minh Quang
    • The Journal of Asian Finance, Economics and Business
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    • 제7권10호
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    • pp.803-810
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    • 2020
  • This objective of this study is to enrich the literature by the debt ratio and enterprise performance of Joint stock companies of Vietnam National Coal and Mineral Industries Holding Corporation Limited (Vinacomin). The debt ratio is an important index of capital structure, and it influences and decides the enterprise performance. Therefore, the determination of reasonable debt ratio level is beneficial to the stable operation of Vinacomin's enterprises. Based on the research conclusion about the effect on capital structure of debt ratio from domestic and foreign scholar, collecting data from 2014-2018 of Vinacomin's enterprises as a research sample, the article conducts research on the relationship between debt ratio and business performance of Vinacomin, as measured by return on total Assets. In addition, the study uses free cash flow, company size, growth opportunity, investment opportunities, operating costs to sales ratio as control variables.The study shows the debt ratio of Joint stock companies of Vietnam National Coal and Mineral Industries Holding Corporation Limited has a negative effect on the enterprise performance. Furthermore, the research results of the article are references for Vinacomin' enterprises in the course of production and business activities, determining a reasonable debt ratio, and improving the operational performance of enterprises.

경험디자인의 개념과 특성에 관한 연구 - 인간의 공간 인지 과정을 중심으로 - (A Study on Definition and Characteristic of Experience Design - Focused on Human's Cognition Process in Space -)

  • 김예진;이정욱
    • 한국실내디자인학회논문집
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    • 제15권4호
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    • pp.138-146
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    • 2006
  • Main elements in definition of space value were physical, formal, and reasonable characteristics in the past. Howener recently, definition of space value is changing by being advanced about study concerned with human's cognition and thinking way in definition and analysis of space. As you see, cognitive psychologists have emphasized the importance of human's cognitive structure and process and studied diverse aspects of human's thinking ; consciousness, perception, memory, image, language, decision-making, inference, and so on. Therefore main elements in definition of space value are five-dimensional, psychological, symbolic, mental, emotional characteristics above physical, formal, and reasonable characteristics. As mentioned above, the conversion of thinking focused on reason to thinking focused on human's spirit and emotion is achieved in contemporary architecture and 'human's experience' in space becomes a very important factor. For that reason, the purpose of this study is consideration of human's cognitive process in space by conversion of thinking and gives a definition about experience. And, I would like to define 'experience design' whose main attribute is experience in space and establish theoretical basis of experience design through theoretical researches about experience. This study on experience design that induces users to participate in space and stimulate human's spirit is a important point in definition of space value not only contemporary interior architecture but also prospective generation.

탄성체로 인한 탄성파의 공명산란 (ELASTIC WAVE RESONANCE SCATTERING FROM AN ELASTIC CYLINDER)

  • 이희남
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2003년도 춘계학술대회논문집
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    • pp.833-838
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    • 2003
  • The problem of elastic wave resonance scattering from elastic targets is studied in this paper. A new resonance formalism to extract the elastic resonance information of the target from scattered elastic waves is introduced. The proposed resonance formalism is an extension of the works developed for acoustic wave scattering problems by the author. The classical resonance scattering theory computes reasonable magnitude information of the resonances in each partial wave, but the phase behaves in somewhat irregular way, therefore, is not clearly explainable. The proposed method is developed to obtain physically meaningful magnitude and phase of the resonances. As an example problem, elastic wave scattering from an infinitely-long elastic cylinder was analyzed by the proposed method and compared to the results by RST. In case of no mode conversion, both methods generate identical magnitude. However, the new method computes exact $\pi$ radian phase shills through resonances and anti-resonances while RST produces physically unexplainable phases. In case of mode conversion, in addition to the phase even magnitudes are different. The phase shifts through resonances and antiresonances obtained by the proposed method are not exactly $\pi$ radians due to energy leak by mode conversion. But, the phases by the proposed method show reasonable and intuitively correct behavior compared to those by RST.

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계층분석과정을 이용한 공공분야 PMO 제도 활성화요인 우선순위 분석 (A Priority Analysis on Influential Factors for Invigorating Project Management Office (PMO) in Public Sectors based on Analytic Hierarchy Process (AHP))

  • 백형충;강필성
    • 산업경영시스템학회지
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    • 제37권4호
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    • pp.42-53
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    • 2014
  • This study identifies influential factors for invigorating the public management office (PMO) system for system integration (SI) projects in public sectors and analyzes the priority of each factor from the point of different stakeholders, i.e., owners, SI company, and PMO. Based on the literature review, four first-level influential factors are identified: legal system maintenance, owner's capability, SI company's capability, and PMO's capability. Among them, the PMO's capability is determined as the most critical factor by all the stakeholders. Among the second-level influential factors, the capabilities of professional engineers and project managers are considered as important among the PMO's capability, whereas the reasonable consulting fee is considered as the most critical factor among the legal system maintenance. With respect to each stakeholder, project management capability is considered as the most important factor for owners, while the reasonable consulting fee is considered as the most important factor for PMO.

소규모 사용종료매립지의 환경특성분석 (A Study on the Environmental Characteristic Analysis at Closed Small Sale Landfill Site)

  • 장성호;조한진;이춘식
    • 한국환경과학회지
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    • 제19권7호
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    • pp.901-905
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    • 2010
  • Emissions of leachate, odor, and landfill gas(LFG) from an open-dumping landfill site do harm to public health by contaminating neighboring soil, underground water, and rivers. Particularly, methane($CH_4$) and carbon dioxide($CO_2$), the main components of LFG, are especially noted as the causing material of the global warming that become seriously recognized worldwide issue. As one of alternatives in managing LFG, incineration of inflammable wastes that are generated during excavation process at an open-dumping landfill has been evaluated. Standard on stabilization for evaluation, neither $CH_4$ density nor $CO_2$ density could not Because meet 'less than 5%' criterion and so it is right to install a gas collection system during landfill renewal to prevent diffusion of odor and collect it. Because it shows considerable heating value, incineration of inflammable wastes might be the reasonable solution from the result of our study.