• 제목/요약/키워드: Pros.

검색결과 539건 처리시간 0.035초

Stochastic simulation models with non-parametric approaches: Case study for the Colorado River basin

  • 이태삼;호세 살라스;제임스 프레리;도널드 프리버트;테리 플립
    • 한국수자원학회:학술대회논문집
    • /
    • 한국수자원학회 2010년도 학술발표회
    • /
    • pp.283-287
    • /
    • 2010
  • Stochastic simulation of hydrologic data has been widely developed for several decades. However, despite the several advances made in literature still a number of limitations and problems remain. In the current study, some stochastic simulation approaches tackling some of the existing problems are discussed. The presented models are based on nonparametric techniques such as block bootstrapping, and K-nearest neighbor resampling (KNNR), and kernel density estimate (KDE). Three different types of the presented stochastic simulation models are (1) Pilot Gamma Kernel estimate with KNNR (a single site case) and (2) Enhanced Nonparametric Disaggregation with Genetic Algorithm (a disaggregation case). We applied these models to one of the most challenging and critical river basins in USA, the Colorado River. These models are embedded into the hydrological software package, Pros and cons of the models compared with existing models are presented through basic statistics and drought and storage-related statistics.

  • PDF

비접지 DC 급전계통에서 전류형 지락보호계전 방법 (Ground fault protective relaying schemes for DC traction power supply system)

  • 정상기;정락교;이성혁;김연수;조홍식
    • 한국철도학회논문집
    • /
    • 제7권4호
    • /
    • pp.412-417
    • /
    • 2004
  • In urban rail transit systems, ground faults in the DC traction power supply system are currently detected by the potential relay, 64P. Though it detects the fault it cannot identify the faulted region and therefore the faulted region could not be isolated properly. Therefore it could cause a power loss of the trains running on the healthy regions and the safety of the passengers in the trains could be affected adversely. Two new ground fault protective relay schemes that can identify the faulted region are presented in this paper. A current limiting device, called Device X, is newly introduced in both system, which enables large amount of ground fault current flow upon the positive line to ground fault. One type of the relaying schemes is called directional and differential ground fault protective relay which uses the current differential scheme in detecting the fault and uses the permissive signal from neighboring substation to identify the faulted region correctly. The other is called ground over current protective relay. It is similar to the ordinary over current relay but it measures the ground current at the device X not at the power feeding line, and it compares the current variation value to the ground current in Device X to identify the correct faulted line. Though both type of the relays have pros and cons and can identify the faulted region correctly, the ground over current protective relaying scheme has more advantages than the other.

5&6 금연프로그램과 5일 교실 금연프로그램의 청소년 금연효과 (Effects of '5&6 Smoking Cessation Program' and 5-day Smoking Cessation Program' on adolescents' smoking behavior)

  • 임은선
    • 보건교육건강증진학회지
    • /
    • 제27권2호
    • /
    • pp.95-108
    • /
    • 2010
  • Objectives: The Purpose was to investigate the effects of the '5&6 smoking cessation program' and '5 days smoking cessation program' on the high school student's perception, urine cotinine, and smoking behaviors. Methods: This study was designed using nonequivalent control group pretest-posttest. The '5&6 smoking cessation program' was applied to the experimental group 1(28 students). The '5 days smoking cessation program' was applied to the experimental group 2(19 students). Control group was 53 students. Data was analyzed using descriptive statistics, $X^2$-test, Fisher's exact test, Independent-sample t-test, Paired t-test, ANOVA, Wilcoxon signed ranks test, Cronbach's coefficient alpha. Results: The '5&6 program' was significantly increased on smoking self-efficacy, stage of smoking cessation behavior change, Cons. for smoking and significantly decreased on daily smoking amount, urine cotinine level than control group. The '5 days program' was significantly decreased on urine cotinine level and Pros. for smoking than control group. The '5&6 program' was significantly increased on stage of smoking cessation behavior change than '5 days program'. Conclusion: This study showed that the '5&6 program and the '5 days program' are effective in adolescent's smoking cessation behaviors.

일 농촌지역 고등학생의 금연 변화단계 및 변화과정 (Stages and Processes of Smoking Cessation among High School Students in Rural Community)

  • 김미영;서순림;함옥경
    • 지역사회간호학회지
    • /
    • 제18권3호
    • /
    • pp.431-440
    • /
    • 2007
  • Purpose: The purpose of this study was to describe stage distribution of current and former smokers and to analyze significant variables that used by adolescents at each stage using the Transtheoretical Model. Methods: A cross-sectional study was performed with 145 students attended to five high schools in one rural area. The survey instruments included stages and processes of change. decisional balance, self-efficacy, and knowledge related to smoking. Results: Among the participants, 47.6% were in the precontemplation and contemplation stages, 20.7% were in the preparation stage, and the other 31.7% were in the action and maintenance stages. Analysis of variance tests revealed that behavioral processes, pros and cons of smoking, and self-efficacy were significantly associated with the stages of smoking cessation, while among 10 processes of change, self-reevaluation, self-liberation, and reinforcement management were significantly different by the stages. Conclusions: The study results suggest that smoking cessation programs should emphasize behavioral strategies, self-efficacy, and decisional balance to help students adopt and maintain smoking cessation.

  • PDF

도로포장 성능보증(Warranty) 계약제도 도입방안에 관한 기초연구 (A Basic Study on the Methodology to Introduce Warranty Contracting for Pavements in Korea)

  • 김태송;서용칠;이상범;구재동
    • 한국건설관리학회논문집
    • /
    • 제9권4호
    • /
    • pp.66-74
    • /
    • 2008
  • 도로포장분야의 성능보증(warranty)계약제도는 유럽, 미국, 일본에서 오랫동안 시행되어 왔거나 시행되기 시작한 제도로서 그 효과가 입증되었거나 입증되고 있다. 본 연구에서는 유럽, 미국, 일본의 성능보증계약제도의 도입 및 운영 현황을 조사하였고, 성능보증계약제도의 장단점과 국내 적용가능성 분석을 통해 성능보증계약제도의 국내 도입방안을 제시하였다. 본 연구의 주요 결론으로 성능보증계약제도를 국내에 적용하기 위한 성능기준 개발의 필요성과, 보증보험 수수료 및 보증기간 등을 고려한 적정공사비 산정방안 마련, 국내에 적합한 성능보증방식 개발 등의 필요성을 제시하였고, 국내에 성능보증계약 제도의 도입을 위한 장단기적 적용방안을 제시하였다.

Injunctions and Hold-up under Weak Patent Protection

  • SIM, KYOUNGBO
    • KDI Journal of Economic Policy
    • /
    • 제42권2호
    • /
    • pp.1-30
    • /
    • 2020
  • This paper analyzes how injunctions relate to patent hold-up problems. To this end, we present a simple model of licensing negotiations between a patent holder and a downstream firm in the shadow of litigation. More specifically, we consider the situation in which an injunction is granted as a matter of course if a patent is found valid and infringed upon in litigation, but the patent holder may be under-compensated due to aspects of the patent remedy system other than injunctions. We show that if the downstream user is unaware of the patent before any investment in initially designing its product, the patent hold-up problems created by injunction threats are worrisome when (i) the redesign process is costly, (ii) the degree of patent protection (by aspects of the patent remedy system other than injunctions) is sufficiently strong and (iii) the injunction is requested not to practice the patented technology exclusively but to collect excessive patent royalties. Even if the downstream user is aware of the patent before the initial investment, the patent hold-up problems do not disappear. The findings here imply that a discretionary approach is required towards denying injunctions against patent infringement. If the degree of patent protection is not sufficiently strong, denying injunctions can exacerbate the under-compensation problem. However, once patent protection improves enough (not necessarily perfectly), we may see a surge of patent hold-up problems, and it would be better to apply alternative patent remedies in place of injunctions when necessary. Lastly, we discuss several possible alternatives to injunctions and their pros and cons.

XML 데이터베이스 지원을 위한 통합 환경 (Unified Framework for XML Database Support)

  • 박상원;민경섭;김형주
    • 한국정보과학회논문지:컴퓨팅의 실제 및 레터
    • /
    • 제6권6호
    • /
    • pp.569-579
    • /
    • 2000
  • 웹에서 정보 전달의 수단으로 등장한 XML은 많은 응용 분야에서 사용될 것이다. 많은 양의 XML 문서를 효율적으로 다루기 위하여 데이타베이스의 지원은 필수적이다. 데이터베이스를 이용하여 XML 데이타를 처리할 때 데이타베이스이 종류뿐만 아니라 그 인터페이스도 중요한 문제이다. 본 논문에서는 관계형 데이터베이스, 객체지향형 데이터베이스 및 랩포를 이용하여 XML 데이타를 저장, 질의하며 그 인터페이스로 XML-뷰, ODMG C++바인딩, OQL, DOM을 사용하였다. 또한 각각의 시스템의 구현을 통하여 각 방법들의 장단점을 논하고, 효율적인 XML 문서 처리에 대한 방법을 제시한다.

  • PDF

간질 치료에서 뇌파의 임상적 유용성에 관한 논란: 긍정적 관점에서 (Controversies in Usefulness of EEG for Clinical Decision in Epilepsy: Pros.)

  • 손영민;김영인
    • Annals of Clinical Neurophysiology
    • /
    • 제9권2호
    • /
    • pp.63-68
    • /
    • 2007
  • The EEG plays an important diagnostic role in epilepsy and provides supporting evidence of a seizure disorder as well as assisting with classification of seizures and epilepsy syndromes. There are a variety of electroclinical syndromes that are really defined by the EEG such as Lennox-Gastaut syndrome, benign rolandic epilepsy, childhood absence epilepsy, juvenile myoclonic epilepsy and also for localization purposes, it is vitally important especially for temporal lobe epilepsy. The sensitivity of first routine EEG in diagnosis of epilepsy has been known about 20-50%, but this proportion rises to 80-90% if sleep EEG and repetitive recording should be added. Convincing evidences suggest that the EEG may also provide useful prognostic information regarding seizure recurrence after a single unprovoked attack and following antiepileptic drug (AED) withdrawal. Moreover, patterns in the EEG make it possible to disclose an ictal feature of nonconvulsive status epilepticus, separate epileptic from other non-epileptic episodes and clarify the clues predictive of the cause of the encephalopathy (i.e., triphasic waves in metabolic encephalopathy). Therefore, regardless of its low sensitivity and other pitfalls, EEG should be considered not only in the situation of new onset episode such as a newly developed, unprovoked seizure or a condition manifesting decreased mentality from obscure origin, but also as a barometer of the long-term outcome following AED withdrawal.

  • PDF

USN의 전송 계층 프로토콜에서 에러 및 흐름제어의 성능 평가 (Analysis of Flow and Congestion control in USN)

  • 차현수;강철균;유승화;김기형
    • 한국정보통신설비학회:학술대회논문집
    • /
    • 한국정보통신설비학회 2008년도 정보통신설비 학술대회
    • /
    • pp.45-50
    • /
    • 2008
  • Many applications of sensor network require connection to the Internet. The transmission protocol of traditional sensor network was designed within the sensor network itself. However, based on 6LoWPAN which can be accessed using IPv6, direct connection is possible between the sensor network and the TCP/IP network outside. Transmission of data in applications of sensor network falls into two main categories. One is a small packet that is periodically produced such as packet related to temperature and humidity. The other is a relatively large packet that brings about network overheads such as images. We investigated the conformance test and pros and cons of application data over the transmission protocol of Zigbee and 6LoWPAN. As a result, both Zigbee and 6LoWPAN have shown low rate of loss for periodic data and have in creased reliability of data transfer. When transmitting streaming image data, both ACK, non ACK mode of Zigbee and UDP of 6LoWPAN minimized transmission time but suffered the consequences of high packet loss. Even though TCP of 6LoWPAN required a long transmission time, we were able to confirm that no loss has occurred.

  • PDF

BCOR 접근법을 이용한 클라우드 컴퓨팅 도입의 의사결정 요인에 관한 연구 (A Study on Decision Making Factors of Cloud Computing Adoption Using BCOR Approach)

  • 이영찬;당응웬하인
    • 한국IT서비스학회지
    • /
    • 제11권1호
    • /
    • pp.155-171
    • /
    • 2012
  • With the continuous and outstanding development of information technology(IT), human being is coming to the new computing era which is called cloud computing. This era brings lots of huge benefits also at the same time release the resources of IT infrastructure and data boom for man. In the future no longer, most of IT service providers, enterprises, organizations and systems will adopt this new computing model. There are three main deployment models in cloud computing including public cloud, private cloud and hybrid cloud; each one also has its own cons and pros. While implementing any kind of cloud services, customers have to choose one of three above deployment models. Thus, our paper aims to represent a practical framework to help the adopter select which one will be the best suitable deployment model for their requirements by evaluating each model comprehensively. The framework is built by applying the analytic hierarchy process(AHP), namely benefit-cost-opportunity-risk(BCOR) model as a powerful and effective tool to serve the problem. The gained results hope not only to provide useful information for the readers but also to contribute valuable knowledge to this new area. In addition, it might support the practitioners' effective decision making process in case they meet the same issue and have a positive influence on the increase of right decision for the organization.