• 제목/요약/키워드: measuring units

검색결과 269건 처리시간 0.031초

Improvement of Power Capability and Field Uniformity with Tapered Coaxial Matching Units in Strip Line for Measuring Electromagnetic Immunity of Vehicular Components

  • Chung, Yeon-Choon;Kang, Tae-Won;Park, Dong-Chul
    • Journal of Electrical Engineering and information Science
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    • 제2권5호
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    • pp.60-64
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    • 1997
  • The design process and construction method of a strip line is described for measuring radiated susceptibility of vehicular components having electrical cables more than 2 min length. he characteristic impedance of the trip line was determined 90$\Omega$ to obtain the field uniformity of $\leq$${\pm}$3 dB in the frequency range from 100 kHz to 500 MHz. Tapered coaxial lines were used instead of the traditional lumped circuit element for the impedence matching units, therefore, the strip line has high power capability. Using these techniques, the field uniformity and power capability of a strip line could be considerably improved.

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초등학교 과학 교과서에서 사용되는 단위에 대한 아동들의 이해도 (Children서s Understanding on Scientific Units in Elementary School Science Textbooks)

  • 김성규;서승조;조태호;백남권;박강은;공정선
    • 한국초등과학교육학회지:초등과학교육
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    • 제21권2호
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    • pp.201-212
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    • 2002
  • This paper aims to find out how did elementary students understand scientific units in science textbooks. The subjects were 191 students of the 6th grade from 7 elementary schools in 3 different areas, consisting of 70 from 4 village schools of, 64 from 2 town schools of Gyeongnam province, and 57 from one city school in Ulsan Metro City. A test was developed based on the analysis of scientific units in the science textbooks and teacher's manuals constructed according to the 6th and 7th National Science Curriculum. The understanding of elementary students' on the scientific units(Temperature, Length, Weight, Volume, Speed, Plane Angle) were surveyed. The result are as follows: Regarding the temperature unit, the students generally well understand why to measure and how to read temperature, but had some problem in recording it, in confusion with the plane angle sign. As for the length unit, they obtained high scores in understanding the purpose of measuring length as well as recording and reading it. Which indicates that they are well aware of and use the unit appropriately. With respect to the weight unit, they got high scores in reading and recording weight, which means most students have no problem using the unit. However, it was found that they do not understand why to use the plate balance scale. The volume unit was one in which the students got relatively lower scores. They do not perceive the object of using a scale cylinder and confuse it with a device of length measurement. The unit of speed is the most difficult one for children's of science to understand, presumably, because it is an derived unit from two basic units. It is also assumed that the students got the highest score in the plane angle unit because they studied the unit immediately before the test. From the children's understanding of science units above the teacher's understanding and teaching methods presumed to play a major role for children to understand and use the science units properly.

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내과계 중환자 섬망발생 선별모형 개발 (Development of a Delirium Occurrence Screening Model for Patients in Medical Intensive Care Units)

  • 이현심;김소선
    • 임상간호연구
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    • 제19권3호
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    • pp.357-368
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    • 2013
  • Purpose: The purpose of this study was to investigate risk factors related to delirium and to develop screening model on delirium occurrence in MICU (Medical Intensive Care Unit) patients. Methods: For developing a preliminary tool for delirium, the data of 166 patients were collected and analyzed. In order to estimate the accuracy and discriminating power for the developed screening model, 98 patients were enrolled. The data used in this study were collected by EMR (Electronic Medical Record) review from January to September in 2012. The collected data were analyzed using SPSS/PC Win 18.0 program. Results: Screening model on delirium in MICU patients was developed using the results of logistic regression. The total score of screening model was 24 point and measuring point was 10 point. When the measuring point is over 10 point, it means that the risk of delirium occurrence is high. The discriminating power and the validity of screening model showed AUC .908 (p <.001) and .935 (p <.001) respectively. This result showed that the screening model on delirium which developed in this study was an appropriate model for screening the delirium risk group in MICU. The sensitivity of the screening model was 83%, specificity 89% and accuracy 84%. Conclusion: The developed screening model on delirium occurrence in MICU should be combined with EMR for screening and preventing delirium in a high risk group.

Clark Cell을 이용한 ppb단위 용존산소 측정기술개발 (Development of pub Level Dissolved Oxygen Measuring Technology using Clark Cell)

  • 정경열;류길수
    • Journal of Advanced Marine Engineering and Technology
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    • 제26권3호
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    • pp.375-381
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    • 2002
  • Measuring of the dissolved oxygen is widely used for the environmental control of natural waters, sewage waste treatment, medical and biochemical studies, soil husbandry, food and drug process control, and prevention of corrosion in boilers. Especially, a power plants need special management for preventing accidents from corrosion, therefore, it is essential to measure the concentration of dissolved oxygen in real-time. In this paper we present a method of measuring dissolved oxygen very accurately up to pub units. This method, called polarograph method, is based on the measures of the electric current generated by the oxidation process in cathode and de-oxidation process in anode, assuming that the amount of the current is proportional to the density of dissolved oxygen.

Clark Cell을 이용한 ppb Level 용존산소 측정기술 개발에 관한 연구 (A Study on the Development of ppb Level Dissolved Oxygen Measuring Technology using Clark Cell)

  • 정경열;이후락;동은석;이수태;류길수
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2001년도 춘계학술대회 논문집
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    • pp.197-201
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    • 2001
  • Measuring of the dissolved oxygen is widely used for the environmental control of natural waters, sewage waste treatment, medical and biochemical studies, soil husbandry, food and drug process control, and prevention of corrosion in boilers. Especially, a power plants need special management for preventing accidents from corrosion, therefore, it is essential to measure the concentration of dissolved oxygen in real-time. In this paper we present a method of measuring dissolved oxygen very accurately up to ppb units. This method, called polarographic method, is based on the measures of the electric current generated by the oxidation process in cathode and de-oxidation process in anode, assuming that the amount of the current is proportional to the density of dissolved oxygen.

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레퍼런스 패턴 기반 면내 위치 측정 방법 (Measuring Method of In-plane Position Based On Reference Pattern)

  • 정광석
    • 융복합기술연구소 논문집
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    • 제2권1호
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    • pp.43-48
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    • 2012
  • Generally, in-plane position of moving object is measured referring to the reference pattern attached to the object. From optical camera to magnetic reluctance probe, there are many ways detecting a variation of the periodical pattern. In this paper, the various operating principles developed for in-plane positioning are reviewed and compared each other. And, a novel method measuring large rotation as well as x, y linear displacements is suggested, including a detailed description of the overall system layout. It is a modified version of the surface encoder, which is a robust digital measuring method. From the surface encoder, the rotation of an object is measured indirectly through a compensated input of optical servo and independently of linear displacements. So, the operating range can be extended simply by enlarging the reference pattern, without magnifying the decoding units.

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Measurement of 3D Spreader Position Information using the CCD Cameras and a Laser Distance Measuring Unit

  • Lee, Jung-Jae;Nam, Gi-Gun;Lee, Bong-Ki;Lee, Jang-Myung
    • 한국항해항만학회지
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    • 제28권4호
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    • pp.323-331
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    • 2004
  • This paper introduces a novel approach that can provide the three dimensional information about the movement of a spreader by using two CCD cameras and a laser distance measuring unit in order to derive ALS (Automatic Landing System) in the crane used at a harbor. So far a kind of 2D Laser scanner sensor or laser distance measuring units are used as comer detectors for the geometrical matching between the spreader and a container. Such systems provide only two dimensional information which is not enough for an accurate and fast ALS. In addition to this deficiency in performance, the price of the system is too high to adapt to the ALS. Therefore, to overcome these defects, we proposed a novel method to acquire the three dimensional spreader information using two CCD cameras and a laser distance measuring unit. To show the efficiency of proposed method, real experiments are performed to show the improvement of accuracy in distance measurement by fusing the sensory information of the CCD cameras and a laser distance measuring unit.

한일간 대기굴절 채널환경을 고려한 전파모델 연구 (Study of the Propagation Model considering Refractive Channel Environment between Korea and Japan)

  • 이경량;김성권
    • 한국전자통신학회논문지
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    • 제8권1호
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    • pp.49-54
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    • 2013
  • 본 논문에서는 대략 250 km 이상 떨어져 있는 한국과 일본의 대기 채널 환경에 대한 분석을 하였으며, 대기 굴절도 변화량에 따르는 한일간의 채널 환경에 Radio Duct 현상이 발생하고 있으며, 그로 인한 전파 월경으로 채널 간섭이 발생하고 있음을 확인하였다. 일본 NHK에서 측정한 한국채널 수신전계강도 실험결과를 바탕으로 인접국간 전파예측모델 P 1546의 유효한 굴절도 변화량 보정치로 1% 시간율에서 -91.80 [N-units/km], 10% 시간율에서 -43.92 [N-units/km], 50% 시간율에서 -586.19 [N-units/km]의 보정된 굴절도 변화량을 제시하였으며, 제시된 굴절도 변화량은 한일간의 대기 채널 환경을 반영하는 실질적인 전파모델 예측수행에 기여할 것으로 기대된다.

중환자의 중증도에 따른 적정 간호인력 수요 산정 (Estimation of Nurse Staffing Based on Nursing Workload with Reference to a Patient Classification System for a Intensive Care Unit)

  • 박영선;송라윤
    • 중환자간호학회지
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    • 제10권1호
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    • pp.1-12
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    • 2017
  • Purpose: This study aimed to estimate the appropriate nurse staffing ratio in intensive care units (ICUs) by measuring nursing workload based on patient's severity and needs, using the Korean Patient Classification System for critical care nurses. Methods: The data were collected from January 18 to February 29, 2016 using a standardized checklist by observation or self-report. During the study period, 723 patients were included to be categorized from I to IV using the patient classification system. Measurement of total nursing workload on a shift was calculated in terms of hours based on the time and motion method by using tools for surveying nursing activities. The nursing activities were categorized as direct nursing care, indirect nursing care, and personal time. Total of 127 cases were included in measuring direct nursing time and 18 nurses participated in measuring indirect and personal time. Data were analyzed using descriptive statistics. Results: Two patients were classified into Class I (11.1%), 5 into Class II (27.8%), 9 into Class III (50%), and two into Class IV (11.1%). The amount of direct nursing care required for Class IV (513.7 min) was significantly more than that required for Class I (135.4 min). Direct and indirect nursing care was provided more often during the day shift as compared to the evening or night shifts. These findings provided the rationale for determining the appropriate ratio for nursing staff per shift based on the nursing workload in each shift. Conclusions: An appropriate ratio of nurse staffing should be ensured in ICUs to re-arrange the workload of nurses to help them provide essential direct care for patients.

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리니어스케일을 이용한 NC 선반의 원 운동정도 측정 (Measuring of Circular Motion Accuracy of NC Lathe using Linear Scales)

  • 김영석;김재열;한지희;정정표;윤원주;송인석
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.1144-1149
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    • 2003
  • It is very important to measure circular motion accuracy of NC lathes it affects accuracy, performance, interchange ability and quality of machine parts machined by the NC lathes in industries. So, in this study, measuring units system to measure circular motion accuracy two axes circular motion accuracy of NC lathes was composed of two optical linear scales installed on the z and x-axes of work coordinate system on NC lathe and a computer inserted with PC counter card enables to obtain measuring data. Here, ATC(Automatic Tool Changer) and moving part of linear scales are fixed with magnet bases in order to measure circular motion accuracy of the ATC of NC lathe. And next, computer software was developed in order to measure the circular motion accuracy of NC lathe under resolution of 0.1 $\mu\textrm{m}$ using two linear scales, and also computer softwares were developed so that measuring data could be modeled on plots and be analyzed numerically,

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