• ALGAE
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• 제24권2호
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• pp.111-120
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• 2009

Choosing an appropriate sample unit is a fundamental decision in the design of ecological studies. While numer-ous methods have been developed to estimate organism abundance, they differ in cost, accuracy and precision.Using both field data and computer simulation modeling, we evaluated the costs and benefits associated with twomethods commonly used to sample benthic organisms in temperatc kelp forests. One of these methods, theTargeted Sampling method, relies on different sample units, each "targeted" for a specific species or group ofspecies while the other method relies on coefficients that represent ranges of bottom cover obtained from visual esti-mates within standardized sample units. Both the field data and the computer simulations suggest that both meth-ods yield remarkably similar estimates of organisnm abundance and among-site variability, although the Coefficientmethod slightly underestimates variability armong sample units when abundances are low. In contrast, the twomethods differ considerably in the effort needed to sample these communities; the Targeted Sampling requiresmore time and twice the persormel to complete. We conclude that the Coeffident Sampling metliod may be bettcrfor environmental monitoring programs where changes in mean abundance are of central conccm and resources arelimiting, but that the Targeted sampling methods may be better for ecological studies where quantitative reIation-ships among species and small-scale variability in abundance are of central concern.

• 한국자동차공학회논문집
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• 제11권6호
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• pp.127-133
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• 2003

NSD(No Spin Differential) has been developed fer a military truck. A benchmarking study for USA and Russian NSD has been carried out. Axiomatic approach has been applied for improving the design. A test code for NSB has been developed and applied to the developed sample. In the test results of comparing the developed sample with the USA imported sample, three major characteristics-the noise, mobility and steerability - are in the range of the intended target. A practical process for the evolution design is proposed.

• 응용통계연구
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• 제8권2호
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• pp.43-54
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• 1995

어가경제조사는 우리나라 어가의 어가경제 및 어업경영에 관한 사항을 조사하는 통계조사이다. 본 연구는 어가경제통계를 생산할 수 있는 표본설계를 제안한다. 연구의 기초 자료로 1990년 어업총조사 자료를 이용하였으며, 시.도별 통계를 위하여 시.도를 부차 모집단으로 하여 설계를 하였다. 표본은 층화 2단 추출을 하였으며, 층화를 위하여 어가소득의 소득함수를 추정하여 이용하였다. 어가의 소득은 선형 추정량을 이용하여 추정하였다.

• 한국정보통신학회논문지
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• 제7권4호
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• pp.798-804
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• 2003

본 논문에서는 프린터 head의 노즐분사제어를 위한 개선된 회로를 설계하였다. 기존 방식에 비하여 비하여 Pad 수를 줄임으로서 노즐 수를 확장시킬 수 있다. 제안된 회로는 사전검증을 위하여 먼저 20개의 노즐을 제어하는 sample 회로로 설계하고 FPGA를 이용하여 동작을 확인하였다. 320개의 노즐제어를 위한 전체회로는 sample 회로를 확장하여 ASIC Full Custom 설계방식을 통하여 설계한 뒤 로직 및 회로 simulation 검증을 하였다. 전체회로는 3$\mu\textrm{m}$ CMOS design rule을 적용하여 layout 및 chip으로 제작되었다.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제1권1호
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• pp.69-78
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• 1995

This study is intended to understand the architectural characteristics and trends of general hospitals in Europe. The Observations, interviewes with the staff, and analyses of related materials were executed through the study-visits of sample hospitals. Some results of the study could be summarized as follows : (1) The architectural characteristics of sample hospitals could be described as the realization of horizontal design concept, application of urban design method, specialization of service departments, intergration of facility design, and planning for the emergency & disaster. (2) The architectural trends of sample hospitals could be suggested as the decentralization of functions, promotion of building standard, enhancement of interior space, consideration of environment, and autonomous management & operation of facilities. (3) The humanistic and environmental approaches from european hospitals would be preferably applicable rather than the popular concept of automation, ultra-modernization and mega-structure in Korea. First of all, the bed-center and proper facilities for disaster should be considered.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.112-112
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• 2010

The purpose of development is to localize a connector for connection of cable and GIS for underground transmission system. The cable connector for GIS provides electrical insulation of GIS housing part and makes connection of ultra high voltage electrical apparatus and power cable by controlling electrical stress between electrodes of power cable termination. Generally Korean switchgear makers are using a connector for GIS made by foreign companies. We manufactured sample by best structure design of great capacity conductor connecting part and then modified the design by analysis of shape and section. We completed the suitable sample for current cycling test condition of conductor connecting part sample and ensured surge characteristics of line by short-time current test.

• 한국임상수의학회지
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• 제32권1호
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• pp.73-77
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• 2015

There has been increasing attention on sample size requirements in peer reviewed medical literatures. Accordingly, a statistically-valid sample size determination has been described for a variety of medical situations including diagnostic test accuracy studies. If the sample is too small, the estimate is too inaccurate to be useful. On the other hand, a very large sample size would yield the estimate with more accurate than required but may be costly and inefficient. Choosing the optimal sample size depends on statistical considerations, such as the desired precision, statistical power, confidence level and prevalence of disease, and non-statistical considerations, such as resources, cost and sample availability. In a previous paper (J Vet Clin 2012; 29: 68-77) we briefly described the statistical theory behind sample size calculations and provided practical methods of calculating sample size in different situations for different research purposes. This review describes how to calculate sample sizes when assessing diagnostic test performance such as sensitivity and specificity alone. Also included in this paper are tables and formulae to help researchers for designing diagnostic test studies and calculating sample size in studies evaluating test performance. For complex studies clinicians are encouraged to consult a statistician to help in the design and analysis for an accurate determination of the sample size.

• 대한의용생체공학회:의공학회지
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• 제44권2호
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• pp.157-165
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• 2023

The purpose of this study was to evaluate the importance of developing slim seats with ergonomic design to improve seat comfort and expand the interior space. Two seats were used for the experiment: a sample seat designed based on hip shape and spinal alignment and a normal seat with a flat design without curves. Subjects sat in both the sample seat and a normal seat applied to the vehicle simulator and the experiment was conducted. The next part of the experiment was conducted in two different postures: a driving posture and a relaxed posture. The subjects filled out a comfort questionnaire immediately after sitting and after 30 minutes. The results showed that the comfort in the sample seat was found to be more comfortable than the normal seat. However, no significant difference was noted for the relaxation posture. Pressure distribution was also recorded immediately after sitting and after 30 minutes. In the case of pressure distribution, it was confirmed that the pressure in the sample seat was more evenly distributed in both the driving and relaxed postures than in the normal seat. The results showed that the ergonomically designed sample seat greatly improved seating comfort and pressure distribution compared to the normal seat, which is a general vehicle seat design.

• 응용통계연구
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• 제36권4호
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• pp.337-347
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• 2023

표본설계는 개체 혹은 집락을 층으로 나눈후 층별로 독립적으로 표본추출하는 층화추출을 종종 채택한다. 층화 전략은 크게 층구분과 표본할당으로 구성되는데 이는 조사연구에서 반복적으로 고려되는 중요한 주제이다. 조사연구에서는 층화다단추출 방식의 복합표본설계를 채택하고 있지만 층효과 혹은 층효율성과 관련하여서 표본론 교재들에서 주로 단순추출에 대해서 다루어지고 있다. 본 연구는 이단추출에 대한 기존 층효율성 측도를 살펴보며 설계효과모형을 적용한 추가적인 층효율성 측도들을 제안하였다. 제안된 측도들을 활용하여 제4기 국민환경기초조사의 고등학교 대상 표본설계의 층화전략에 대해 평가하였다.

• 한국초전도ㆍ저온공학회논문지
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• 제19권2호
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• pp.53-57
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• 2017

In superconducting power devices including power cables in which high temperature superconducting (HTS) tapes are utilized, a reliable electrical insulation should be achieved for its maximum performance. For an efficient design of HTS superconducting devices, a comparative evaluation of the mechanical and thermal propperties for various insulation materials at cryogenic temperatures is required. Especially, in the process of the property evaluation of the sheet-shaped insulation materials, anisotropy according to the machining direction should be considered because the mechanical and thermal properties are significantly influenced by the sample orientation. In this study, the cryogenic thermal and mechanical properties of various insulation material sheets such as PPLP, Cryoflex, Teflon, and Kapton were determined considering sample orientation. All samples tested at cryogenic temperature showed significantly higher tensile strength as compared with that of room temperature. The ultimate tensile strength at both temperature conditions significantly depended upon the sample orientation. The thermal properties of the insulation materials exhibited a slight difference among samples depending on the orientation: for the PPLP and Cryoflex, the CD orientation showed larger thermal contraction up to 77 K as compared to the MD one. MD samples in PPLP and Cryoflex showed a lower CTE and thermal contraction which made it more promising as an insulation material due to its comparable CTE with HTS CC tapes.