• 제목/요약/키워드: Discharge test

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리튬 2차 전지용 정극 활물질 LiMn$_2$O$_4$의 열처리 조건에 따른 충방전 특성 (Charge/discharge characteristics by heat treatment condition of cathode active material LiMn$_2$O$_4$ for Li rechargeable batteries)

  • 정인성;구할본
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1996년도 추계학술대회 논문집
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    • pp.369-372
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    • 1996
  • We prepared LiMn$_2$O$_4$ by reacting stoichiometric mixture of LiOH.$H_2O$ and MnO$_2$ (mole ratio 1 : 1) and heating at 80$0^{\circ}C$ for 24h, 36h, 48h, 60h and 70h. We obtained through X-ray diffraction that lattice parameter varied as function of heat treatment time. heated cathode active materials at 80$0^{\circ}C$ for 36h, (111)/(311) peak ratio was 0.37. It expected good charge/discharge characteristics. When (111)/(311) peak ratio was 0.37, it will be that crystal structure is farmed very well. In the result of charge/discharge test When heated at 80$0^{\circ}C$ for 36h, charge/discharge characteristic of LiMn$_2$O$_4$is the most property. It agree with our expectation.

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휴대전자기기용 저용량 리튬이온 배터리의 충방전 열화 기구 분석 및 모니터링 (Evaluation and monitoring of degradation mechanism of Li-ion battery for portable electronic device)

  • 변재원
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제13권2호
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    • pp.129-140
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    • 2013
  • As a fundamental experimental study for reliability improvement of lithium ion secondary battery, degradation mechanism was investigated by microscopic observation and acoustic emission monitoring. Microstructural observation of the decomposed battery after cycle test revealed mechanical and chemical damages such as interface delamination, microcrack of the electrodes, and solid electrolyte interphase (SEI). Acoustic emission (AE) signal was detected during charge and discharge of lithium ion battery to investigate relationships among cumulative count, discharge capacity, and microdamages. With increasing number of cycle, discharge capacity was decreased and AE cumulative count was observed to increase. Observed damages were attributed to sources of the detected AE signals.

토목섬유를 사용한 무처리 연약지반과 성토사이의 수평배수층 (Geotextiles Horizontal Drain between Earth Fills and Natural Soft Ground)

  • 이형규;공길용;김현태
    • 한국농공학회지
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    • 제44권4호
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    • pp.129-138
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    • 2002
  • This paper presents a study on the discharge capacity of geotextiles as a horizontal drain layer placed between the layers of earth fill and natural soft ground. Required discharge capacity of geotextiles as drain layers estimated by consolidation analysis is proportional to the consolidation coefficient of the ground soils and the width of the earth fills. The field discharge capacity of the geotextiles are measured by the hydraulic transmissivity test. And the results show wide variation according to the material characteristics of geotextiles, water content of the soils, vertical pressure, and etc. For the short horizontal drain length, geotextile filter mat can be used for the horizontal drain layer. And f3r the long drain($25{\sim}55m$), it is used for the drain together with Bord Drain.

몰드변압기용 부분방전 측정 센서 및 시스템 개발 (Development of Partial Discharge Measuring Sensor and System for Mold Transformer)

  • 강동식;선종호;조국희;이상민;윤영호;이동준;어수영;김주현;최교남
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 추계학술대회 논문집 전기설비전문위원
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    • pp.99-102
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    • 2005
  • In order to development of diagnosis system for mold transformer, partial discharge measurement technique is recommended the best effective method for the evaluation of insulation condition on high voltage winding part. However, this technique was not applied to mold transformer yet. The purpose of this paper is to describe the method of partial discharge measurement for mold transformer with coupling sensor and measuring system. As we reviewed and developed the on-line partial discharge test technique, ceramic coupling sensor, measuring system, terminal box and index parameters.

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Analysis of the Effects of SD Plasma on Aerodynamic Drag Reduction of a High-speed Train

  • Lee, Hyung-Woo;Kwon, Hyeok-Bin
    • Journal of Electrical Engineering and Technology
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    • 제9권5호
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    • pp.1712-1718
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    • 2014
  • Experimental analysis according to the plasma actuator design variables was performed in order to verify the effects of sliding discharge plasma on aerodynamic drag reduction of a high-speed train. For the study, sliding discharge plasma actuator and high-frequency, high-voltage power supply were developed and experimented to figure out the best design variables for highest ionic wind velocity which could reduce the drag force. And then, 5% reduced-scale model of a high-speed train was built for wind tunnel test to verify it. From the results, it was confirmed that sliding discharge plasma had contribution to reduce the drag force and it had the potential to be applied to real-scale trains.

맞춤형 지지교육이 심부전증 환자의 신체, 정서적 상태 및 삶의 질에 미치는 효과 (Effects of Tailored Supportive Education on Physical, Emotional Status and Quality of Life in Patients with Congestive Heart Failure)

  • 이은숙;신은숙;황선영;채명정;정명호
    • 성인간호학회지
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    • 제25권1호
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    • pp.62-73
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    • 2013
  • Purpose: This study was conducted to examine the effects of tailored supportive education on physical, psychological status and quality of life in the patients with congestive heart failure (CHF) who had not participated previously in cardiac rehabilitation program. Methods: This study was used a non-equivalent control pre-post design, conducted on 64 CHF patients under medical treatment in a hospital. The experimental group (n=31) received the tailored supportive educational program (once 1~2 days before discharge and 6 times after discharge through outpatient visits or telephone contact: once every week for the first 4 weeks after discharge and once every 2 weeks for the remaining 4 weeks). The control group (n=33) received a traditional discharge education. Data were analyzed using descriptive statistics, ${\chi}^2$-test, Fisher's exact test, t-test and repeated measure ANOVA using the SPSS/ WIN 18.0 program. Results: Participants in the experimental group showed the significantly increased scores of the quality of life (F=16.01, p<.001), and the significantly decreased scores of physical function (F=7.27, p=.009), depression (F=8.25, p=.006) and anxiety (F=4.11, p=.047), when compared to those of the control group. Conclusion: The findings indicated tailored supportive education was an effective intervention care in physical, emotional status and quality of life for CHF patients.

원내 심장재활프로그램이 심혈관질환자의 행동수정과 삶의 질에 미치는 영향 (Effects of the Inpatient Cardiac Rehabilitation Program on Behavioral Modification and Quality of Life in Patients with Coronary Artery Disease)

  • 송라윤;이해정
    • 대한간호학회지
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    • 제30권2호
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    • pp.463-475
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    • 2000
  • The purpose of the study was to identify the effects of inpatient cardiac rehabilitation programs on motivation, the performance of health behavior, and quality of life in patients with coronary artery disease. The subjects consisted of 31 patients who participated in the rehabilitation program during their hospital stay, and were compared with 34 patients who did not participate. The study results are as follows: 1. The mean of cardiac risk factor scores for the subjects was 22.5 (SD = 5.5) at the level of low to moderate risk with some possibility to improve. The physiological and behavioral risk factors for the subjects were also in the normal range or slightly above the normal range. 2. The motivation level to preform health behaviors for both groups was improved after discharge. Also, perceived self-efficacy was significantly higher for the program participants than for the comparison group at the post-test. 3. The performance of cardiac related health behaviors improved for both groups after discharge, but there were no significant differences between the two groups. The program participants reported better performance in most health behaviors at the post-test, but the results failed to reach a statistical significant level. 4. As for motivation and health behavior, the subjects in the both groups showed an improved quality of life after the discharge. In addition, the program participants produced significantly higher scores in health and functioning dimension than the comparison group during the post-test. In conclusion, the study partially supported the effects of the inpatient cardiac rehabilitation program to motivate and improve the quality of life, and provide the need to apply early rehabilitation interventions for the patients after cardiac events. Further study with a longitudinal design is also suggested to verify the effect of cardiac rehabilitation program from hospitalization to discharge and subsequently to fully recover to the level of pre-hospitalized state.

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노인 입원환자의 퇴원계획 프로그램 개발을 위한 퇴원 서비스 요구도 조사 (A Study on Discharge Service Needs for Discharge Planning Program Development to the Elderly at the Hospital)

  • 이선자;신은영;장숙랑
    • 한국보건간호학회지
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    • 제15권2호
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    • pp.376-386
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    • 2001
  • I. Background The problem of discharging patients from hospital have been well documented in the literature over the last 20 years. They included poor communication between hospital and community, inadequate notice of discharge, over-reliance on informal support and lack of statutory support, inattention to patients needs before leaving hospital, and wasted or duplicated visits by community nurses. Most patients discharged from hospital are able to return home with little or no support, while others will require a 'package of care' to support them back to good health. Patient with complex care needs, including the frail elderly and those with mental health problems, may require continuing care in special housing, residential, or nursing homes. With this population,effective discharge arrangement is needed and the study on this problem is urgent in Korea because the Medical Reform Project is on suspension of success. II. Results of the Study: 1. Discharge service needs assessed on 360 elderly patients who were hospitalized during the survey period at four university hospitals. Patients want to know the information on disease management after discharge. Follow-up telephone service is the most frequently checked service. 2. Multidisciplinary Discharge Planning is recommended at the hospital level to reduce the readmission and decrease the length of stay. 3. Further research is needed to validate and test the assumption of the solution which is developed in this research.

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Experimental Study on Air Decomposition By-Product Under Creepage Discharge Fault and Their Impact on Insulating Materials

  • Javed, Hassan;LI, Kang;Zhang, Guoqiang;Plesca, Adrian Traian
    • Journal of Electrical Engineering and Technology
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    • 제13권6호
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    • pp.2392-2401
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    • 2018
  • Creepage discharge faults in air on solid insulating material play a vital role in degradation and ageing of material which ultimately leads to breakdown of power equipment. And electric discharge decompose air in to its by-products such as Ozone and $NO_x$ gases. By analyzing air decomposition gases is a potential method for fault diagnostic in air. In this paper, experimental research has been conducted to study the effect of creepage discharge on rate of generation of air decomposition by-products using different insulating materials such as RTV, epoxy and fiberglass laminated sheet. Moreover XRF analysis has been done to analyze creepage discharge effect on these insulating materials. All experiments have been done in an open air test cell under constant temperature and pressure conditions. While analysis has been made for low and high humidity conditions. The results show that the overall concentration of air decomposition by-products under creepage discharge in low humidity is 4% higher than concentration measured in high humidity. Based on this study a mathematical relationship is also proposed for the rate of generation of air decomposition by-products under creepage discharge fault. This study leads to indirect way for diagnostic of creepage discharge propagation in air.

환자이탈군 특성요인과 이탈환자 예측모형에 관한 연구 (A Study on the Characteristics of Prematurely Discharged Patients and the Model for Predicting Premature Discharge)

  • 민경진;송규문;김광환
    • 한국의료질향상학회지
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    • 제9권1호
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    • pp.18-32
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    • 2002
  • Background : We developed a model for predicting premature discharge and identifying related factors. Methods : Prediction model was developed by data mining techniques. Basic data were collected from the total discharge data base of a university hospital in Chungnam Province during the period from July 1, 1999 to June 30, 2000. Results : 1. Among 22,873 patients, the number of patients discharged with usual discharge orders were 21,695 or 94.8%. The number of the prematurely discharged patients were 1,178 or 5.2%. 2. The primary reason for unusual discharge was transfer to other hospital. Move to a local hospital closer to their home and burdensome medical expenses were main reasons. 3. Predictability of each model was tested using the top 10 percent of patients with the highest probabilities of premature discharge. The neural network model was chosen as the most appropriate model for predicting prematurely discharged patients. 4. Ten percent of the total number of patients had been selected randomly to test the effectiveness of the neural network model. We have chosen the threshold of the neural network model as 0.7. The number of patients who were expected to discharge prematurely was 312. Among them, 241 had been discharged prematurely (77.2%). Conclusion : Of the several data mining techniques used, the neural network model was the most effective, It can be used to identify and manage the patients who are expected to discharge prematurely.

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