• 전력전자학회:학술대회논문집
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• 전력전자학회 2018년도 추계학술대회
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• pp.36-38
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• 2018

As the battery capacity requirement increases, battery cells are connected in a parallel configuration. However, the sharing current of each battery cell becomes unequal due to the imbalance between cell's impedance which results the mismatched states of charge (SOC). The conventional fixed-resistance balancing methods have a limitation in battery equalization performance and system efficiency. This paper proposes a battery equalization method based on dynamic resistance technique, which can improve equalization performance and reduce the loss dissipation. Based on the SOC rate of parallel connected battery cells, the switches in the equalization circuit are controlled to change the equivalent series impedance of the parallel branch, which regulates the current flow to maximize SOC utilization. To verify the method, operations of 4 parallel-connected 18650 Li-ion battery cells with 3.7V-2.6Ah individually are simulated on Matlab/Simulink. The results show that the SOCs are balanced within 1% difference with less power dissipation over the conventional method.

• 전기학회논문지
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• 제66권12호
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• pp.1740-1744
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• 2017

This paper describes the preparation and characteristics of a battery capacitor and module for solar power system. A cylindrical 30,000F battery capacitor ($60{\times}138mm$) was assembled by using the $LTO(Li_4Ti_5O_{12})$ electrode as an anode and $NMC(LiNiMnCoO_2)-LCO(LiCoO_2)$ as a cathode. The battery capacitor has reduced energy density and power density under high CC(constant current) and CP(constant power) conditions. Battery capacitor module (16V, 11Ah) was fabricated using an asymmetric hybrid capacitor with a capacitance of 30,000F. In order to determine the characteristics of the battery capacitor Module for solar power system, battery capacitor cells were connected in series with active balancing circuit. As a result of measuring the 100w LED lamp, it was discharged at the voltage of 15V~10V, and the compensation time at discharge was measured to be about 4979s. Experimental results show that it can be applied to applications related to solar power system by applying battery capacitor module.

• 대한치과보철학회지
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• 제31권4호
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• pp.565-579
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• 1993

This study was accomplished to analyse and compare the occlusal contact patterns during eccentric mandibular movements in adult with normal occlusion. 50 subjects(male 27, female 23), who had natural occlusion and no symptom of temporomandibular disorder, were selected. Teeth contact patterns during mandibular eccentric movements were recorded and the distribution of tooth contacts in maximum intercuspation analysed by T-scan system. And then, tooth contact numbers recored by T-scan and silicone bite registration at centric occlusion were analysed and compared. The results obtained were as follows : 1. Antero-posteriorly, the qualitative center of occlusal contacts in centric occlusion were in the first molar areas, but there was a slight deviation in left-right directions. Thus, distribution of occlusal contacts were not bilaterally symmetric. 2. During the mandibular movements from centric occlusal position to right lateral and left lateral directions, the frequency that maxillary canine joined in lateral guidance was relatively high, but pure canine protected occlusion or pure group function occlusion had small frequency. 3. During mandibular protrusive movement, one or more maxillary central incisors frequently joined in protrusive guidance. 4. During mandibular eccentric movements, working and balancing side premature contact was observered in relatively high frequency. 5. In centric occlusal position, the numbers of occlusal contacts recorded on T-scan were relatively smaller than on silicone bite registration.

• Journal of Power Electronics
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• 제7권4호
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• pp.343-352
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• 2007

This paper proposes a modularized charge equalization converter for hybrid electric vehicle (HEV) lithium-ion battery cells, in which the intra-module and the inter-module equalizer are Implemented. Considering the high voltage HEV battery pack, over approximately 300V, the proposed equalization circuit modularizes the entire $M^*N$ cells; in other words, M modules in the string and N cells in each module. With this modularization, low voltage stress on all the electronic devices, below roughly 64V, can be obtained. In the intra-module equalization, a current-fed DC/DC converter with cell selection switches is employed. By conducting these selection switches, concentrated charging of the specific under charged cells can be performed. On the other hand, the inter-module equalizer makes use of a voltage-fed DC/DC converter for bi-directional equalization. In the proposed circuit, these two converters can share the MOSFET switch so that low cost and small size can be achieved. In addition, the absence of any additional reset circuitry in the inter-module equalizer allows for further size reduction, concurrently conducting the multiple cell selection switches allows for shorter equalization time, and employing the optimal power rating design rule allows fur high power density to be obtained. Experimental results of an implemented prototype show that the proposed equalization scheme has the promised cell balancing performance for the 7Ah HEV lithium-ion battery string while maintaining low voltage stress, low cost, small size, and short equalization time.

• 대한물리의학회지
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• 제11권4호
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• pp.93-103
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• 2016

PURPOSE: The purpose of this study is to determine the effect of therapeutic exercise on pain, range of motion and strength, and balance ability in a patient with an anterior ankle impingement (AAI). METHODS: A-32-year-old male presented limited ankle motion and pain with forced dorsiflexion at both ankle joints. In response, a therapeutic exercise program consisted of ankle joint mobilization, strength exercises using an elastic band, and proprioceptive exercises including semi-squats and a one-legged standing exercise with open and closed eyes. The program was performed for 40 min/day, twice per week, for 8 weeks. Pain, range of motion (ROM), and muscle strength (ankle dorsiflexion, plantarflexion, inversion, and eversion), as well as a one-legged standing test of both ankles, were measured before and after 4 and 8 weeks of therapeutic exercise. RESULTS: VAS decreased in both ankles after 8 weeks of exercise, respectively, compared to baseline levels. Range of motion and strength increased in both ankles for dorsiflexion, plantarflexion, inversion, and eversion after 8 weeks of exercise compared to baseline levels. In addition, the ability to perform a one-legged standing test with eyes opened and closed improved in both legs after 8 week of exercise compared to baseline levels. CONCLUSION: These results suggest that therapeutic exercise improves pain, ROM, muscle strength, and balancing ability in patients with AAI.

• 대한한의학원전학회지
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• 제24권4호
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• pp.23-32
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• 2011

The texts of "Hwangjenaegyeong(黃帝內經)" explains Hakjil(瘧疾) in detail, especially in the "Jahak(刺瘧)" chapter, where bloodletting treatment is applied in many cases. The following paper categorized and organized Hakjil(瘧疾) cases treated by bloodletting methods, then analyzed applicable subjects and appropriate time for the procedure based on the texts. Afterwards, the mechanism for the cessation of Hakjil(瘧疾) seizures was examined. The findings of this research are as follows. 1. In the contents of "Hwangjenaegyeong(黃帝內經)", the appropriate time for acupuncture and bloodletting procedure is when Hakjil(瘧疾) seizures start to present themselves. 2. When a seizure takes place as a symptom of the body getting rid of the Hak(瘧) pathogen, Yanggi(陽氣) rushes to the locus of the pathogen, causing congestion of Gi(氣) and Blood(血) resulting in static blood[瘀血]. Therefore, bloodletting at the time of seizure initiation helps the flow of Gi(氣) and Blood(血), preventing the rush of Yanggi(陽氣). This is a restoration of the balancing function of Eum(陰) and Yang(陽), which indicates that bloodletting not only promotes smooth flow of Gi(氣) and Blood(血), but extends its effects to mental functions that balances Eum(陰) and Yang(陽). 3. Although Hakjil(瘧疾) seizures are presented in terms of Gi(氣) and Blood(血) in symptoms such as chill and fever[寒熱], static blood[瘀血], pain, etc., a fundamental disturbance in mental functions that control cold and heat seems to be present.

• 대한간호학회지
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• 제46권2호
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• pp.260-270
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• 2016

Purpose: This study was conducted to develop a program to help emergency nurses overcome compassion fatigue, and to analyze the effects of the program. Methods: A nonequivalent control group pretest-posttest design was used. There were 14 participants in the experimental group and 18 subjects in the control group. The program was comprised of five, weekly 80-minute sessions including understanding and assessment of compassion fatigue, enhancing positive affect, balancing work-life, planning self care, training in relaxation techniques and cognitive restructuring, and getting social support. Research variables were ego-resiliency, compassion satisfaction and compassion fatigue of the ProQOL 5, and salivary cortisol. Data were analyzed using Chi-square test, independent t-test, and paired t-test. Results: The first hypothesis, "There will be a difference in scores for ego resiliency between the experimental group and the control group". was not supported. The second hypothesis, "There will be a difference in scores for compassion satisfaction between the experimental group and the control group" was supported (t=2.15, p=.046). The third hypothesis, "There will be a difference in scores for compassion fatigue between the experimental group and the control group" was not supported. Conclusion: The first program for emergency nurses to overcome compassion fatigue in Korea was effective in increasing emergency nurses' compassion satisfaction and decreasing salivary cortisol level in the experimental group. Therefore, this program for overcoming compassion fatigue is useful to increase emergency nurses' compassion satisfaction. However replication studies of short-term intensive program reflecting emergency nurses' opinion are needed.

• 한국전문물리치료학회지
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• 제14권1호
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• pp.55-63
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• 2007

This study was designed to examine the relationship between clinical symptoms, self-efficacy, and performance of women with osteoarthritis. It is a survey study of 60 women who were diagnosed as osteoarthritis and given medical treatments from September, 2005 to October, 2005 in hospital 'H' located in Yongin-si. For clinical symptoms, radiographs of the subjects' knees were taken and evaluated the pathology grade by the Kellgren-Lawrence grade. Pain and stiffness was measured by the measure of WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index), and functional reach test was measured in order to examine balancing abilities. Self-efficacy was measured by a tool which has revised the ASES (Arthritis Self-Efficacy Scale), and performance was measured by recording the difficulty of the WOMAC measurements themselves, and the time taken for 20 m walking, going up and down 9 stairs, and 5 sit-down and stand-up repetitions. The resulting differences in the other variables according to performance and the relationship between performance with variables are the following. First, an increase in pain in women with osteoarthritis led to decreased functional ability. Second, an increase in stiffness in women with osteoarthritis led to a decrease in functional ability. Third, a decrease in balance in women with osteoarthritis led to a decrease in functional ability. Fourth, a decrease in self-efficacy in women with osteoarthritis led to a decrease in functional ability. Fifth, the variables for estimating the performance by self-report were pain and self-efficacy. The variables for estimating the performance by recording the time taken was balance and self-efficacy. As a result factors such as pain, balance and self-efficacy in women with osteoarthritis were closely related to performance. Based on the results, it seems that physical therapy programs to decrease pain and to increase the balance in women with osteoarthritis, and psychological approaches to increasing self-efficacy are needed. I hope that the results of this study will be useful data for clinical management and intervention for women with osteoarthritis.

• 수면정신생리
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• 제17권2호
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• pp.85-90
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• 2010

목 적: 인삼은 한국을 비롯한 아시아 국가에서 전통적으로 불면증의 치료에 사용되어 왔으며 쥐를 이용한 동물실험에서 수면을 촉진시키는 효과가 있다는 연구 결과가 있어왔다. 하지만 이러한 효과를 입증할 만한 임상 실험은 거의 이루어지지 않았다. 이에 본 연구에서는 고려 홍삼이 수면에 미치는 영향을 알아보고자 한다. 방 법: 건강한 성인 남성 20명을 대상으로 하였으며 이들은 무작위로 홍삼군과 위약군에 배정되어 2주간의 실험이 진행되었다. 홍삼군의 경우 하루 4,500 mg의 홍삼을 섭취하였다. 실험 시작시점과 2주 후인 종료시점에 수면다원검사를 시행하여 두군간의 변수의 변화를 비교하였다. 결 과: 총 15명의 대상자, 즉 홍삼군 8명과 위약군 7명이 수면다원검사를 시행 받았으며 홍삼군이 위약군 보다 실험 종료 시점에서 3단계 수면이 증가한(p=0.087) 반면에 2단계 수면이 감소하는(p=0.071) 경향을 나타냈다. 결 론: 본 연구 결과는 고려 홍삼이 깊은 잠은 증가시키고 얕은 잠은 감소시키는 경향이 있음을 보여준다. 이는 통계적으로 유의한 결과는 아니지만 홍삼이 수면의 질을 향상시키는 데 효과적임을 짐작하게 한다. 그러나, 보다 많은 대상군과 충분한 홍삼 용량으로 보다 긴 기간 동안 진행되는 연구를 통해 고려 홍삼의 수면에 대한 효과를 확인할 필요가 있다.

• 한국조경학회지
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• 제52권1호
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• pp.71-86
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• 2024

기후위기가 심각해지는 현 시점에 서식처 보호 및 복원과 생물다양성 보전 등 도시공원의 생태적 기능의 중요성이 증가하고 있다. 생태공원은 「도시공원 및 녹지 등에 관한 법률」과 「자연공원법」이 정한 공원의 유형에 해당하지 않아 전국적으로 조성되는 수많은 생태공원의 법적 근거 역시 다양하고 관리주체도 상이하여 체계적으로 지정·관리되지 못하고 있는 현실이다. 도시공원 패러다임의 생태적 전환과 국토 생태계의 총체적, 통합적 관리를 위한 자연공원 체계의 개선을 위해 생태공원의 법적 지위를 명확히 하는 것은 중요하다. 이를 위해 관련 법령을 분석하여 문제점과 법제적 개선 방향을 도출하였다. 첫째, 국토교통부와 환경부 법률의 연계성이 떨어지고 이원화된 공원 체계 속에 생태공원의 법적 지위는 모호한 것으로 나타나, 공원 관련 법제의 개정을 통해 생태공원을 명확히 규정해야 한다. 둘째, 생태공원은 생태계의 보호와 복원, 생물다양성의 보전과 증진, 자연관찰과 생태학습 및 여가활동의 균형을 도모하며 생태적 방법으로 조성·관리되는 지속가능한 공원으로 정의할 수 있으며 지속적인 논의를 통해 다듬어가야 할 것이다. 셋째, 공원 관련 행정 협력 체계에서 국가와 지방자치단체의 역할을 체계화하고 거버넌스 구축을 통해 새로운 공원조성·관리 모형을 수립해야한다. 넷째, 생태공원 서식처의 특성은 개별법의 영향을 받으므로 시설 중복결정의 가능성을 열어둘 필요가 있다. 다섯째, 생태공원의 목표, 원칙, 시설물의 조성 기준을 갖추도록 세부 지침과 표준 조례가 필요하다. 여섯째, 법률의 개정과 더불어 지자체의 조례 역시 구체화되어야 한다. 이 연구는 생태공원을 제도적으로 명확히 규정해야 한다는 문제의식을 기반으로 현재 생태공원과 관련된 다양한 법적 현실을 추적한 문헌 연구이다. 다양한 이해관계자들의 의견을 실증적으로 반영하지 못한 한계를 가지나, 이러한 법적 고찰은 생태공원 조성 기반을 체계화하여 도시의 생태계를 보전하며 시민들에게 자연체험과 학습의 기회를 제공할 수 있는 정책 방향을 제시하는데 기여할 수 있다.