• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2019년도 추계학술대회
• /
• pp.216-217
• /
• 2019

The battery powered electric vehicle (EV) is one of most promising technologies in 21^st century. Though the lithium batteries are playing an important role in the EVs, they are only applicable until their capacities reach 80%, the end of its useful first life. Yet, these batteries can live a second life such as Energy Storage Systems (ESS). In order to utilize the Residual Useful Life (RUL) of the batteries the State of Health (SOH) of them needs to be estimated by a nondestructive test such as Electrochemical Impedance Spectroscopy (EIS) technique. Though many kinds of different EIS instruments are commercially available, most of them can only test a battery module less than 10V and the price of the instrument is very high. In this paper a low-cost EIS instrument suitable for measuring the impedance spectrum of the high voltage battery module is proposed and its validity is verified through the experiments. In order to prove the accuracy of the developed EIS instrument its measured impedance spectrum is compared with the results obtained by a commercial instrument. The Chi Square value calculated between two impedance spectrum measured by both developed and commercial instruments are less than 2%, which prove the strong correlation between two results.

• 임상간호연구
• /
• 제14권1호
• /
• pp.139-150
• /
• 2008

Purpose: The aim of this study was to develop instrument measuring the relocation stress syndrome for patients transferred from intensive care unit to general ward in Korea. Method: For item construction, components were drawn from an extensive review of the literature, existing instruments and the result of qualitative approach. A total 48 items were selected for the first draft. Ten experts evaluated this instrument for content validity and the number of items was reduced to 29. To refine and test reliability and validity of the instrument, data were collected from the 594 patients following transfer from intensive care unit. Results: Preliminarily twenty-nine items were generated through content validity and a pilot study. Using corrected items to total correlation coefficient, this instrument was further shortened to a 25 item scale. Factor analysis extracted a total of 23 items with a 5-point Likert-type scale. Relocation Stress Syndrome (RSS) included three subscales; physical factors (12 items), Patient's recognition to health care providers (8 items), and emotional factors (3 items). The RSS established content validity, construct validity, and reliability. Conclusion: This instrument demonstrates good reliability and validity, and therefore it is an appropriate measurement of assessing relocation stress syndrome in ICU to ward transition period.

• 한국환경교육학회지:환경교육
• /
• 제21권4호
• /
• pp.79-93
• /
• 2008

The purpose of this study was to develop an instrument for measuring elementary school students' environmental literacy. The process of instrument development was four phases. The first two phases involved defining the domain of the construct, writing an initial pool of 55 items, and reviewing the items for revision and deletion. These steps were taken to provide the evidence of content-related validity, and to reduce a number of items. The third phase was, through item analysis, to determine the most appropriate items for the environmental literacy for the elementary school students. For the forth phases, the fifth and sixth students in elementary school participated in this survey. To examine the reliability and validity of environmental literacy for the elementary school students, internal consistency estimate, and factor analysis were used. The results of this study were summarized as follows; Firstly, thorough factor analysis, we developed Environmental Literacy Instrument for the elementary school students, consisted of total 41 items (knowledge 8 items, emotion 11 items, skill 10 items, and behavior 13 items); Secondly, Cronbach's alpha was .783 for knowledge, .832 for emotion, .866 for skill and 8.61 for behavior.

• Journal of Biosystems Engineering
• /
• 제16권4호
• /
• pp.363-371
• /
• 1991

It is important to measure the somatic informations for stockbreeding automatization. This study was carried out for the development of wireless measurement system of temperature in living animals. New method to measure somatic temperature was developed using the single-channel wireless instrument. This system was constructed by oscillator, temperature sensor, wireless transmitter and receiver circuit, single processing circuit, and microcomputer. Two types of sensor were used and compared to measure the temperature. The thermistor sensor was more sensitive and accurate than platinum resistance sensor, however both sensors were performed efficiently. The single-channel wireless measurement systems developed could measure the somatic temperature successfully and offered a versatile system.

• 지역사회간호학회지
• /
• 제30권1호
• /
• pp.25-37
• /
• 2019

Purpose: The purpose of this study was to develop an instrument for measuring nursing information literacy competency, and then to examine the validity and reliability of the instrument. Methods: The developmental process of the instrument includes construction of a conceptual framework, generation of initial items, verification of content validity, preliminary study, extraction of final items, and psychometric testing. Its content validity was verified by three experts from nursing and nursing informatics. Its construct, convergent, and discriminant validity was examined in confirmatory factor analysis. Finally, its criterion validity was measured with Pearson's correlation. The tool's reliability was examined by Cronbach's ${\alpha}$. The participants include 382 nurses from four hospitals and one university hospital. Results: Twenty seven items in total were selected for the final scale, and the results of the confirmatory factor analysis were supported with acceptable model fit, which were named competency for identifying problem, potential sources for information, searching fine information, evaluating information, acquising and managing of information, using information ethically, and integrating new information. The convergent, discriminant and criterion validities were also supported. The Cronbach's ${\alpha}$ coefficient was .93. Conclusion: The instrument is valid and reliable to comprehensively assess nurses' information literacy competency, and to provide a basic direction for developing nursing information literacy program.

• 한국입자에어로졸학회지
• /
• 제10권4호
• /
• pp.163-167
• /
• 2014

Particle number portable emission measurement system (PN-PEMS) is an instrument for measuring number concentration of automobile exhaust. The principle of some pre-existing commercial PN-PEMS is to charge particles and display the number of particles by measuring current. However, this method has some problems for measuring exhaust. In this study, to solve these issues, we have developed a single particle counting PN-PEMS based condensation particle counter (CPC). The PN-PEMS based CPC does not affect driving conditions and it is convenient for mobile because the instrument is small and light in structure. We evaluated counting efficiency of PN-PEMS based CPC by using electrostatic method (electrometer and Faraday cup).

• 대한간호학회지
• /
• 제35권6호
• /
• pp.1091-1100
• /
• 2005

Purpose: The purpose of this study was to develop an instrument to measure nursing professional values. Method: Forty preliminary items were selected by classifying 223 basic items extracted via a literature study and in-depth interviews of subjects and testing the relevance of their contents. In order to verify the reliability and relevance of the preliminary instrument, data was collected from 504 nurses in 3 general hospitals. Result: As a result of the item analysis, 29 items were selected from a total of 40 items. Five factors were extracted by factor analysis, and the total variance was $51.5\%$. For the explanation of variances by factors, the 1 st factor, 'self-concept of the profession' accounted for $14.8\%$, the 2nd factor, 'social awareness' $12.1\%$, the 3rd factor, 'professionalism of nursing' $9.8\%$, the 4th factor, 'the roles of nursing service' $9.1\%$, and the 5th factor, 'originality of nursing', $5.6\%$. Cronbach's Alpha of those 29 items was .9168, which was high. Conclusion: This paper is meaningful in a way that it developed a tool capable of measuring nursing professional values, which reflects the characteristics of our country. In order to re-verify the relevance and stability of this tool, it is necessary that comparative studies should be conducted.

• 제어로봇시스템학회논문지
• /
• 제16권9호
• /
• pp.876-882
• /
• 2010

Stroke patients can't use their hands because of the paralysis their fingers. Their fingers are recovered by rehabilitating training, and the rehabilitating extent can be judged by measuring the pressing force to be contacted with two fingers (thumb and first finger, thumb and middle finger, thumb and ring finger, thumb and little finger). But, at present, the grasping finger force of two-finger can't be accurately measured, because there is not a proper finger-force measuring system. Therefore, doctors can't correctly judge the rehabilitating extent. So, the finger-force measuring system which can measure the grasping force of two-finger must be developed. In this paper, the finger-force measuring system with a three-axis force sensor which can measure the pressing force was developed. The three-axis force sensor was designed and fabricated, and the force measuring device was designed and manufactured using DSP (Digital Signal Processing). Also, the grasping force test of men was performed using the developed finger-force measuring system, it was confirmed that the grasping forces of men were different according to grasping methods.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2006년도 추계학술대회 논문집 전기물성,응용부문
• /
• pp.194-195
• /
• 2006

This study evaluated the impedance characteristics of earth termination system and developed a variable frequency-typed inverter (measuring tool) for the utilization in ground design for lightning protection. The variable-frequency-typed inverter were composed of rectification part, voltage adjuster, IGBT controller and measuring part. Meanwhile, the square wave signal of variable frequency converted its frequency up to lightning surge band by using an IGBT after rectifying an alternating current (AC). It conducted performance evaluation of ground impedance of actual earth termination system by using the developed measuring tool for ground impedance and confirmed that such impedance-oriented performance evaluation was effective in the design of lightning protection.

• 대한전기학회논문지
• /
• 제45권1호
• /
• pp.9-13
• /
• 1996

The high precision of electrical power and energy measurements with wide range of frequency and power factor can be achieved by using the thermo-electrical power comparators. The paper describes the development of a precision power measuring system by using a ac/dc power comparator for measurement of power. Based on a thermal principle, the instrument performs ac-dc transfer for ac power measurements in the range of currents from 0 to 5 $A_{ms}$ , voltages from 0 to 240 $V_{ms}$ , power factors from 0 to 1 and frequencies from 0 to 1000 Hz. Two thermal converters with two heater are used in the functional element of the comparators. The ac-dc transfer accuracy is better than 20 ppm at unity power factor and better than 50 ppm at 0.5 power factor. (author). 8 refs., 5 figs., 3 tabs.