• 제목/요약/키워드: PSDs

검색결과 41건 처리시간 0.029초

액체유출법에 의한 폴리에스테르 직물의 기공 크기 및 분포 측정 (Pore Size and Distribution of Polyester Fabrics Determined by Liquid Extraction Method)

  • 이동화;여숙영;김은애
    • 한국의류학회지
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    • 제21권1호
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    • pp.206-216
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    • 1997
  • The purpose of this study was to determine the pore size distributions (PSDs) of polyester woven fabrics by using liquid extraction method. Three types of PSDs-percent PSD, PSD per unit area of sample and PSD per unit weight of sample-were evaluated. Plain, twill and satin polyester fabrics with various fabric counts were used as specimens. Results showed that the interyarn PSDs reflected the fabric characteristics such as the fabric count and the weave type and the intrayarn PSDs reflected the thread characteristics such as the number of fibers, the fiber diameter, the thread diameter and the thread twist. Of three types of PSDs, the PSD per unit area of sample best reflect fabric and thread characteritics. As the fabric count decreased, rc increased and interyarn pore volume increased. The PSDs were skewed to the small pore sizes and the pore volumes decreased in the order of plain> twill> satin. As the number of fibers, the fiber diameter and the thread twist decreased, the intrayarn pore volumes were increased.

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섬망 환자의 지각된 낙인 척도 개발 및 타당성 검증 (Development and Validation of Perceived Stigma of Delirium Scale)

  • 김선영;김성완;김재민;신일선;윤진상
    • 정신신체의학
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    • 제23권2호
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    • pp.121-128
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    • 2015
  • 연구목적 본 연구는 '섬망환자의 지각된 낙인 척도(Perceived Stigma of Delirium Scale, PSDS)'를 개발하고 신뢰도와 타당도를 평가하여 섬망을 경험한 환자의 지각된 낙인을 측정하고자 시행되었다. 방 법 기존 문헌과 낙인 관련 척도를 고찰 및 참고하여 7문항의 PSDS 예비 척도를 구성하고, 섬망에서 회복된 128명의 환자를 대상으로 PSDS와 디스트레스 온도계(Distress Thermometer, DT)를 측정하였다. 탐색적 요인 분석을 시행하여 낙인 척도의 요인 구조를 확인하였다. 신뢰도 검증을 위해 내적 일치도와 검사-재검사 신뢰도를 분석하였다. 공시타당도는 PSDS 총점과 DT의 상관 분석을 통해 확인하였다. 결 과 예비 척도의 요인 분석을 시행한 결과 단일 요인이 추출되었다. 예비 척도 7문항 중 1개 문항은 낮은 요인 부하량을 가져 제외하였다. PSDS의 내적 일치도의 분석을 위해 시행한 Cronbach's ${\alpha}$ 값은 0.85였다. PSDS 총점의 검사-재검사간 상관 계수는 0.71이었으며, 각 문항별 상관 계수는 0.58에서 0.83사이었다. PSDS의 총점과 DT는 유의한 상관관계를 보였다. 결 론 본 연구는 PSDS가 섬망에서 회복된 환자의 지각된 낙인을 측정하는데 있어서 신뢰할만한 도구임을 확인하 였다. 본 척도 연구를 기반으로, 후속 연구와 다기관 연구를 통해 임상적 유용성의 평가가 이루어져야 할 것이다.

우리 나라 토양의 입도특성 (The Particle Size Distribution of Korean Soils)

  • 우철웅;장병욱
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2003년도 학술발표논문집
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    • pp.163-166
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    • 2003
  • In this study, a grouping of particle-size distributions(PSDs) by means of the fuzzy c-means clustering method(FCM) was presented. The classification was performed with the whole and the major soil series representing pedological origin. In case of the major soil series, PSDs were clustered as $2{\sim}4$ groups and the characteristics of clustering results were quite different between the soil series. It was found that the characteristics of PSDs at center of each class can be explained by formation process of each soil series. In case of whole soil data, PSDs were classified to 8 classes in which 4 classes were single mode and 4 classes were bimode distributions. Through this study, it is concluded that pedogenetic process is a plausible explanation for grain size distribution of soils.

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Pitfalls in Reimbursement Decisions for Oncology Drugs in South Korea: Need for Addressing the Ethical Dimensions in Technology Assessment

  • Cho, Eun;Park, Eun-Cheol;Kang, Myoung Sheen
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권6호
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    • pp.3785-3792
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    • 2013
  • This study aimed to discover to what extent ethical issues are considered in the reimbursement decision process based on health technology assessment (HTA) in Korea, especially for oncology medications. Public summary documents (PSDs) published by the Health Insurance Review and Assessment Service (HIRA) were analyzed for empirical and normative factors. For external comparison, PSDs presented by corresponding institutions of Australia and the United Kingdom were employed. Furthermore, the opinions of eight expert oncologists were obtained regarding the accountability of the evidence in PSDs. Among 7 oncology drugs, there were differences in the final decisions and empirical factors considered, such as selected comparators and interpretation of evidence between the PSDs from the three institutions. From an ethical viewpoint, the following matters were deficient in the HTA decision-making process for oncology drugs: clear and reasonable standards; identifying and evaluating ethical values; and public accountability for reasonableness about decisions and due process.

PSD와 구면반사를 이용한 3자유도 미소 변위의 정밀측정 (Precision Displacement Measurement of Three-DOF Micro Motions Using Position Sensitive Detector and Spherical Reflector)

  • 이재욱;조남규
    • 한국정밀공학회지
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    • 제20권7호
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    • pp.99-104
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    • 2003
  • A precision displacement measurement system of 3-DOF micro motions is proposed in this paper. The measurement system is composed of two diode lasers, two quadratic PSDs, two beam splitters and a sphere whose surface is highly reflective. In this measurement system, the sphere reflector is mounted on the platform of positioning devices whose 3-DOF translational motions are to be measured, and the sensitive areas of two PSDs are oriented toward the center point of the sphere reflector. Each laser beam emitted from two diode laser sources is reflected at the surface of sphere and arrives at two PSDs. Each PSD serves as a 2-dimensional sensor, providing the information on the 3-dimensional position of the sphere. In this paper, we model the relationship between the outputs of two PSDs and 3-DOF translational motions of the sphere mounted on the object. Based on a deduced measurement model, we perform measurement simulation and evaluate the performance of the proposed measurement system: linearity, sensitivity, and measurement error. The simulation results show that the proposed measurement system can be valid means of precision displacement measurement of 3-dimensional micro motions.

자기부상열차 시험노선의 궤도틀림 분석 (Irregularity Analysis of Maglev Test Track)

  • 김상범;강기동;한형석;이종민
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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    • pp.2400-2404
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    • 2011
  • Power spectral density (PSD) model of irregularities for the maglev test track is presented. Track irregularities (gauge, cant, twist and vertical) were calculated from the survey data of sleepers on the test track. PSD model was constructed from the estimated PSDs of each track irregularities. Versine (gauge, cant, twist, vertical and lateral) of the track is obtained and their PSDs were estimated, too. Presented PSD model can be used for the analysis of levitation stability and ride quality of the maglev system.

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PSD를 이용한 초정밀소형공작기계의 기하학적 오차 측정 (Measurement of Geometric Errors of an Ultra Precision mMT Using PSDs)

  • 권설령;권성환;양승한
    • 대한기계학회논문집A
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    • 제35권1호
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    • pp.53-58
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    • 2011
  • 초정밀 소형공작기계는 초정밀가공분야에서 마이크로/메조 스케일 가공품의 정밀제조기술의 핵심으로 개발되어 왔다. 소형초정밀기계의 기하학적 오차는 가공품의 품질에 큰 영향을 미치기 때문에 반드시 분석 및 보정되어야 한다. 기존 소형공작기계의 기하학적 오차는 주로 레이저 간섭계로 측정되었으나 한번의 설치로 모든 기하학적 오차를 측정할 수 없고 까다로운 절차를 따라야 한다. 그 대안으로써 PSD 로 구성된 측정시스템이 개발되었으나 측정가능거리가 PSD 의 유효영역에 한정되었다. 본 논문에서는 측정가능거리를 확장시키고 설치오차를 최소화하여 6-자유도 기하학적 오차를 측정하는 시스템을 제안하고 민감도 해석과 실험을 통하여 이 측정 시스템의 정확도를 증명하였다.

삼면반사체를 이용한 6자유도 미소 변위 측정 (Measurement of Fine 6-DOF Displacement using a 3-facet Mirror)

  • 박원식;조형석;변용규;박노열
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.50-50
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    • 2000
  • In this paper, a new measuring system is :proposed which can measure the fine 6-DOF displacement of rigid bodies. Its measurement principle is based on detection of laser beam reflected from a specially fabricated mirror that looks like a triangular pyramid having an equilateral cross-sectional shape. The mirror has three lateral reflective surfaces inclined 45$^{\circ}$ to its bottom surface. We call this mirror 3-facet mirror. The 3-facet mirror is mounted on the object whose 6-DOF displacement is to be measured. The measurement is operated by a laser-based optical system composed of a 3-facet mirror, a laser source, three position-sensitive detectors(PSD). In the sensor system, three PSDs are located at three corner points of a triangular formation, which is an equilateral triangular formation tying parallel to the reference plane. The sensitive areas of three PSDs are oriented toward the center point of the triangular formation. The object whose 6-DOF displacement is to be measured is situated at the center with the 3-facet mirror on its top surface. A laser beam is emitted from the laser source located at the upright position and vertically incident on the top of the 3-fatcet mirror. Since each reflective facet faces toward each PSD, the laser beam is reflected at the 3-facet mirror and splits into three sub-beams, each of which is reflected from the three facets and finally arrives at three PSDs, respectively. Since each PSD is a 2-dimensional sensor, we can acquire the information on the 6-DOF displacement of the 3-facet mirror. From this principle, we can get 6-DOF displacement of any object simply by mounting the 3-facet mirror on the object. In this paper, we model the relationship between the 6-DOF displacement of the object and the outputs of three PSDs. And, a series of simulations are performed to demonstrate the effectiveness of the proposed method. The simulation results show that the proposed sensing system can be an effective means of obtaining 3-dimensional position and orientation of arbitrary objects.

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구면 반사체를 이용한 3 자유도 변위 측정 기법 (A Measuring Method for 3-DOF Displacement by Using Spherical Reflector)

  • 권기환;문홍기;조남규
    • 대한기계학회논문집A
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    • 제26권12호
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    • pp.2687-2694
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    • 2002
  • A precision displacement measuring system is proposed, which can detect the 3-DOF translational motions of precision positioning devices. The optical system, which is composed of two diode-laser sources and two quadratic PSDs, is adapted to detect the position of the spherical reflector usually mounted on the platform of positioning devices. Each of the laser beams from diode-laser sources is reflected at the highly reflective surface of the sphere; hence, the 3-dimensional position of the sphere causes the directional change of the reflected beams, which is detected by the PSDs. In this paper, we define the relationships between the output values of the two PSDs and the 3-DOF translational motions of the sphere. Based on a deduced measurement model, we perform measurement simulation and evaluate the performance of the proposed measurement system: linearity, sensitivity, measuring range, and measurement error. The results show that the proposed measuring method is very useful for the measurement of the precision displacement of 3-DOF micro motions.

강체의 6자유도 미소 변위 측정 (Measurement Method for Fine 6-DOF Displacement of Rigid Bodies)

  • 박원식;조형석
    • 제어로봇시스템학회논문지
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    • 제8권3호
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    • pp.208-219
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    • 2002
  • A novel measurement method to obtain the 6-DOF motions of arbitrary rigid bodies is proposed in this paper. The method adopts a specially fabricated mirror called 3-facet mirror, which looks like a triangular pyramid haying an equilateral cross-sectional shape. The mirror is mounted on the objects to be measured, illuminated by a laser beam having circular profile, and reflects the laser beam in three different directions. Three PSDs(position sensitive detector) detect the three beams reflected by the mirror, respectively. From the signals of the PSDs, we can calculate the 3-dimensional position and orientation of the 3-facet mirror, and thus enabling us to determine the 3-dimensional position and orientation of the objects. In this paper, we model the relationship between the 3-dimensional position and orientation of an object in motion and the outputs of three PSDs. A series of experiments are performed to demonstrate the effectiveness and accuracy of the proposed method. The experimental results show that the proposed sensing system can be an effective means of obtaining 3-dimensional position and orientation of arbitrary objects and provide resonable measurement accuracy.