• Title/Summary/Keyword: Valid Time

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A Preliminary Study of the Validity of the Concealed Information Test Using P300 and Reaction Time (P300과 반응시간을 이용한 거짓반응의 타당성에 대한 예비적 연구)

  • Park, Gun-Tae;Rhee, Moon-Sung;Kim, Moo-Jin;Roh, In-Soo;Jeong, Phil-Ja
    • Anxiety and mood
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    • v.4 no.2
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    • pp.99-103
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    • 2008
  • Objectives : The authors sought to examine the differences in the number of P300 detected by subjects in experimental and control groups when exposed to relevant stimuli. In addition, the authors tried to determinethe subjects' reaction time when asked to respond to relevant stimuli. Methods : The subjects were 20 informed female volunteers aged 22-38 years (median age : 24). Relevant stimuli (concealed information) were created by unknowingly exposing the two groups to obscene pictures and semantic questions. The number of P300 detected and the length of reaction time were compared between the two groups. Results : Contrary to theauthors' expectations, there were no significant differences in the number of P300 detected or in the length of reaction time between the two groups. Conclusions : These results indicate that, unlike a polygraph test, concealed information tests adopting P300 and reaction time as major physiological responses ofsubjects exposed to meaningful personal information might not serve as a valid practical tool in the field of criminal psychology. However, further studies involving a greater number of subjects are needed before a final conclusion regarding the validity of this new type of concealed information test can be drawn.

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A Study of the Transient Flow Characteristics of a Vacuum Ejector-Diffuser System.

  • Rajesh, G.;Kim, H.D.
    • Proceedings of the KSME Conference
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    • 2007.05b
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    • pp.2769-2774
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    • 2007
  • In vacuum ejector-diffuser systems where a finite volume secondary chamber is used, the secondary jet exhibits transient characteristics during start-up. A steady state is achieved after some time in which mass entrainment prevails indefinitely inside the ejector, though there is no flow from the secondary chamber. An attempt is made in this work to study the infinite entrainment of secondary jet into the primary jet from a finite secondary chamber, with the help of a computational fluid dynamics method. The present study is also intended to identify the operating range of vacuum ejector-diffuser systems where the steady flow assumption can be applied without uncertainty. The results obtained show that the only condition in which an infinite mass entrainment is possible is the generation of a re-circulation zone near the primary nozzle exit. The flow in the secondary chamber attains a state of dynamic equilibrium at this point. Steady flow assumption is valid only after this point.

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Free Vibration Analysis of Perforated Plate Submerged in Fluid

  • Jhung, Myung-Jo;Jo, Jong-Chull;Jeong, Kyeong-Hoon
    • Journal of Mechanical Science and Technology
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    • v.20 no.9
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    • pp.1323-1338
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    • 2006
  • An analytical method to estimate the coupled frequencies of the circular plate submerged in fluid is developed using the finite Fourier-Bessel series expansion and Rayleigh-Ritz method. To verify the validity of the analytical method developed, finite element method is used and the frequency comparisons between them are found to be in good agreement. For the perforated plate submerged in fluid, it is almost impossible to develop a finite element model due to the necessity of the fine meshing of the plate and the fluid at the same time. This necessitates the use of solid plate with equivalent material properties. Unfortunately the effective elastic constants suggested by the ASME code are found to be not valid for the modal analysis. Therefore in this study the equivalent material properties of perforated plate are suggested by performing several finite element analyses with respect to the ligament efficiencies.

Validity of Instrument Development Research in Korean Nursing Research (한국의 도구개발 간호연구에서의 타당도에 대한 고찰)

  • Lee, Kyunghee;Shin, Sujin
    • Journal of Korean Academy of Nursing
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    • v.43 no.6
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    • pp.697-703
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    • 2013
  • Purpose: This integrative review study was done to analyze methods used for validation studies in Korean nursing research. Methods: In this study, the literature on instrument development in nursing research from Research Information Sharing Service (RISS) and major nursing journal databases in Korea were examined. The MeSH search terms included 'nursing', 'instrument', 'instrument development', 'validation' and 189 articles were included in the review. Results: The most frequently reported validity type was content validity, followed by construct validity, and criterion validity. One third reported a single type of validity, and 15% of the studies demonstrated three kinds of validity at the same time. In about 40% of the studies, both content and construct validity were examined. Conclusion: The results of the study indicate that it is necessary to provide a wider variety of evidence to establish whether instruments are valid enough to use in nursing research.

Voltage-Mode 1.5 Gbps Interface Circuits for Chip-to-Chip Communication

  • Lee, Kwang-Jin;Kim, Tae-Hyoung;Cho, Uk-Rae;Byun, Hyun-Geun;Kim, Su-Ki
    • ETRI Journal
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    • v.27 no.1
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    • pp.81-88
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    • 2005
  • In this paper, interface circuits that are suitable for point-to-point interconnection with an over 1 Gbps data rate per pin are proposed. To achieve a successful data transfer rate of multi-gigabits per-second between two chips with a point-to-point interconnection, the input receiver uses an on-chip parallel terminator of the pass gate style, while the output driver uses the pullup and pulldown transistors of the diode-connected style. In addition, the novel dynamic voltage level converter (DVLC) has solved such problems as the access time increase and valid data window reduction. These schemes were adopted on a 64 Mb DDR SRAM with a 1.5 Gbps data rate per pin and fabricated using a 0.10 ${\mu}m$ dual gate oxide CMOS technology.

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Planar Region Extraction for Visual Navigation using Stereo Cameras

  • Lee, Se-Na;You, Bum-Jae;Ko, Sung-Jea
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.681-686
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    • 2003
  • In this paper, we propose an algorithm to extract valid planar regions from stereo images for visual navigation of mobile robots. The algorithm is based on the difference image between the stereo images obtained by applying Homography matrix between stereo cameras. Illegal planar regions are filtered out by the use of labeling of the difference images and filtering of invalid blobs using the size of each blob. Also, illegal large planar regions such as walls are removed by adopting a weighted low-pass filtering of the difference image using the past difference images. The algorithms are experimented successfully by the use of stereo camera system built in a mobile robot and a PC-based real-time vision system.

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System Availability Analysis using Markov Process (Markov Process를 활용한 시스템 가용도 분석 연구)

  • Kim, Han Sol;Kim, Bo Hyeon;Hur, Jang Wook
    • Journal of the Korean Society of Systems Engineering
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    • v.14 no.1
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    • pp.36-43
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    • 2018
  • The availability of the weapon system can be analyzed through state modeling and simulation using the Markov process. In this paper, show how to analyze the availability of the weapon system and can use the Markov process to analyze the system's steady state as well as the RAM at a transient state in time. As a result of the availability analysis of tracked vehicles, the inherent availability was 2.6% and the operational availability was 1.2% The validity criterion was defined as the case where the difference was within 3%, and thus it was judged to be valid. We have identified the faulty items through graphs of the number of visits per state among the results obtained through the MPS and can use them to provide design alternatives.

A Study on the Development of the Urban River Environment Evaluation Indexes Using Delphi Method (델파이 기법을 활용한 도시 하천 환경 평가지표 선정)

  • Park, Eun-Ha;Kim, Jin-Won;Oh, Choong-Hyeon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.18 no.6
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    • pp.27-38
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    • 2015
  • This study is for deriving an evaluation system which fits to the domestic urban river. For this, two times of Delphi survey was conducted to various experts who are eminent for ecology, urban design, governance, landscape architecture, hydrology. The purpose was for analysing validity and getting extra opinion of evaluation items which were preferentially have chosen. Reflecting $1^{st}$ survey's opinions as changing the word or explaining more details, the second survey was conducted, In this time, all evaluation items were analysed as valid and experts agreed with that. In conclusion, the evaluation items, "Amenity", "Biodiversity", "Ecosystem service", "Governance", "Management", which are for evaluating domestic urban river environment were derived.

Mode Choice Models for Freight Transportation Using SP Data (SP자료를 이용한 화물수송수단 선택모형의 개발 -컨테이너 내륙운송을 중심으로-)

  • 하원익;남기찬
    • Journal of Korean Society of Transportation
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    • v.14 no.1
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    • pp.81-99
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    • 1996
  • This study aims to assess the potential competition among road, rail, and coastal transport under various scenarios concerning the future inland container transport systems in Pusan-KyungIn corridor. For this SP approaches are adopted to collect data from shippers and carriers, and multinomial logit models are estimated at disaggragate level. The results of the analysis indicate that the SP data are reliable, and that the mode choice models estimated are valid. The results also indicate that the most effective policy to divert the freight volume from road to other modes is to reduce freight rates for the railway, and is to transport time for the coastal water with improved reliability.

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Daily peak load forecasting considering the load trend and temperature (수요경향과 온도를 고려한 1일 최대전력 수요예측)

  • 최낙훈;손광명;이태기
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.15 no.6
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    • pp.35-42
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    • 2001
  • Since daily peak load forecasted data are essential to economic operation and power monitor, the technique of accurate forecasting is needled. The chief advantage of forecasting technique using neural network and fuzzy theory is high accuracy and operative implicity but the loaming time is long, and it makes large forecasting error when the load changes rapidly. This paper has resented a new forecasting technique to improve those faults and the forecasting technique prove to be valid by forcasted results.

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