• Journal of Power Electronics
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• 제16권5호
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• pp.1735-1742
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• 2016

This paper proposes an interleaved five-level boost converter based on a switched-capacitor network. The operating principle of the converter under the CCM mode is analyzed. A high voltage gain, low component stress, small input current ripple, and self-balancing function for the capacitor voltages in the switched-capacitor networks are achieved. In addition, a three-loop control strategy including an outer voltage loop, an inner current loop and a voltage-balance loop has been researched to achieve good performances and voltage-balance effect. An experimental study has been done to verify the correctness and feasibility of the proposed converter and control strategy.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 추계학술대회 논문집
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• pp.439-443
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• 1996

A fuzzy teaming controller is experimentally designed to control the ball k beam system in this paper. Although most fuzzy controllers have been built just to emulate human decision-making behavior, it is necessary to construct the rule bases by using a learning method with self-improvement when it is difficult or impossible to get them only by expert's experience. The algorithm introduces a reference model to generate a desired output and minimizes a performance index function based on the error and error-rate using the gradient-decent method. In our balancing experiment of the ball ＆ beam system, this paper shows that the fuzzy control rules by learning are superior to the expert's experience.

• Bulletin of the Korean Chemical Society
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• 제12권6호
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• pp.699-705
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• 1991

Procedures to perform reliable relativistic self-consistent-field (RSCF) calculations are described. Using light atoms and molecules, it is demonstrated that the present method always yields correct nonrelativistic limit by employing a sufficiently large value for the speed of light in RSCF calculations. Many problems associated with analytic expansions of the Dirac equations can be computationally avoided by kinetically balancing the basis sets for large and small component spinors. Results of RSCF calculations for Ne, Kr, $H_2$, and LiH indicate very small relativistic effects for these systems as expected. Trends found is these molecules, however, may be useful in understanding relativistic effects for molecules with similar valence electronic structures and heavier atoms.

• Clinical and Experimental Reproductive Medicine
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• 제47권4호
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• pp.263-268
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• 2020

Autophagy, which has the literal meaning of self-eating, is a cellular catabolic process executed by arrays of conserved proteins in eukaryotes. Autophagy is dynamically ongoing at a basal level, presumably in all cells, and often carries out distinct functions depending on the cell type. Therefore, although a set of common genes and proteins is involved in this process, the outcome of autophagic activation or deficit requires scrutiny regarding how it affects cells in a specific pathophysiological context. The uterus is a complex organ that carries out multiple tasks under the influence of cyclic changes of ovarian steroid hormones. Several major populations of cells are present in the uterus, and the interactions among them drive complex physiological tasks. Mouse models with autophagic deficits in the uterus are very limited, but provide an initial glimpse at how autophagy plays a distinct role in different uterine tissues. Herein, we review recent research findings on the role of autophagy in the uterine mesenchyme in mouse models.

• Journal of Power Electronics
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• 제18권4호
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• pp.1051-1066
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• 2018

This study presents a novel step-up switched capacitor multilevel inverter (SCMLI) structure. The proposed structure comprises 2 unequal DC voltage sources, 4 capacitors, and 14 unidirectional power switches. It can synthesize 21 output voltage levels. The important features of the proposed topology are its self-voltage boosting and inherent capacitor voltage balancing capabilities. Furthermore, a cascaded structure of the proposed SCMLI with an asymmetric DC voltage source configuration is presented. The proposed topology and its cascaded structure are compared with conventional and other recently developed topologies in terms of different aspects, such as the required components to produce a specific number of output voltage levels, the total standing voltage (TSV) and peak inverse voltage of the structure, and the maximum number of switches in the conducting path. Furthermore, a cost function is developed to verify the cost-effectiveness of the proposed topology with respect to other topologies. The TSV of the proposed topology is significantly lower than those of other topologies. Moreover, the developed topology is cost-effective compared with other topologies. A detailed operating principle, power loss analysis, and selection procedure for switched capacitors are presented for the proposed SCMLI structure. Extensive simulation and experimental studies of a 21-level inverter structure prove the effectiveness and merits of the proposed SCMLI.

• 한국컴퓨터정보학회논문지
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• 제12권6호
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• pp.31-39
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• 2007

온라인 사이버 교육 시스템에서 수강생들에게 파일을 안정적으로 전송하는 것이 필수적이지만, 사용자의 요구가 일시적으로 많아질 경우, 처리부하가 집중되는 과부하 현상으로 시스템이 중지될 수도 있다. 이를 해결하기 위한 방법으로 P2P 기반의 소프트웨어적 해결책을 사용한다. 하지만, 이러한 해결책은 피어의 자율성을 고려할 경우, 서비스 지연 현상을 초래하거나 심지어는 부분적으로 서비스를 할 수 없는 결과를 초래하여 오히려 시스템의 효율성이 떨어지는 문제점이 있다. 본 논문에서는 P2P 네트워크 환경 하에서 피어의 자율성이 고려한 콘텐츠 전송 시스템에 적합한 효율적인 부하 분산 정책을 제안한다. 제안된 방법은 인접한 피어들의 서브네트워크를 구성하여 서버의 부하를 분산시켰다. 또한 서브네트워크 내에서 서버 역할을 수행할 피어들이 다수일 경우, 각 피어들의 성능과 사용 패턴 정보를 기반으로 피어의 자율성으로 인한 서비스 지연을 최소화하는 서버 선정기법을 제안하고 기존의 방법에 비해 우수함을 시뮬레이션을 통하여 보였다.

• 대한정형도수물리치료학회지
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• 제17권2호
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• pp.19-24
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• 2011

Background: The elderly are likely to fall due to physical and mental atrophies, and experiencing falls may result in fear of falls and lack of self-confidence, which also leads to hesitation to physical activities and changes in walk and balance, the major variables in independent daily life. Methods: In three senior citizen centers located in D city, 22 elderly women aged 65 or older were chosen, and they filled in the questionnaire which included their agreement to voluntarily participate in the survey and medical histories. As to whether they had falls experience, the medical history items in the questionnaire asked them if they had falling down or falls once a year, twice for the three years. The objects were divided to NFE (non-falls experience) and FE (falls experience). Results: 1. As to walking abilities, significant difference was found between NFE and FE regarding walk width, stepping with two feet, and stride length while there was no significant different in terms of cadence. 2. As to balancing abilities, was significant difference between NFE and FE in terms of the physical body center area. As to the sit-to-stand, tandom gait test, no significant difference was found, and neither in the timed up and go test. Conclusions: The elderly with falls experience has inferior walking and balancing abilities to those without falls experience, and thus they are more exposed to the risks of falls.

• 한국통신학회논문지
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• 제32권11B호
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• pp.700-708
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• 2007

이 논문은 통신서비스의 소매가격과 접속료에 대한 유인적 규제제도를 제안한다. 이러한 유인적 규제제도는 병목설비를 가지고 있는 독점적 사업자로 하여금 자발적으로 사회적으로 최적인 접속과 소매서비스를 제공하게 한다. 중간투입 설비를 가진 상류기업은 이부제 요금을 통해, 전체 통합이윤을 실현할 수 있다는 것은 잘 알려진 사실이다. 이 논문은 첫째, 규제기업의 수지보전(budget balancing)과 관련하여 접속료와 소매요금 등을 규제하는 규제프레임워크를 제시한다. 둘째, 접속(상류)과 소매서비스(하류) 모두에서 이부제 요금제도가 어떻게 적용될 수 있는가를 소개하고, 비용함수에 대해 규제자가 불완전한 정보를 가지고 있는 경우, 유인적 규제제도의 적용가능성과 그 효과를 분석하고 있다. 셋째, 자기선택 제도를 사용하여, 접속과 소매부문에서 어떻게 사회적 최적인 상태가 도달되는지를 보여준다.

• Journal of Acupuncture Research
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• 제35권3호
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• pp.129-137
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• 2018

Background: The purpose of this study was to determine the effect of Postural Yinyang correction of the temporomandibular joint (functional cerebrospinal therapy) on temporomandibular disorder. Methods: Medical records of 21 outpatients were reviewed who were diagnosed with temporomandibular joint disorder, unspecified (K0769) and treated at the Department of Acupuncture & Moxibustion, Dong-Eui University Korean Medicine Hospital from May $1^{st}$, 2017 to April $30^{th}$, 2018. Patients received more than 10 treatments of upper cervical manipulation and performed self-exercise therapy more than 3 times a day and wore an accurate balancing appliance in the oral cavity for more than 8 hours per day. To estimate the efficacy, visual analogue scale (VAS), numerical rating scale (NRS), maximum mouth opening (MMO), symptom intensity scale (SIS), max SIS (MSIS), symptom frequency scale (SFS), mandibular function impairment questionnaire (MFIQ) and 5-point Likert scale were used. Results: NRS and MSIS were significantly improved during each period. VAS, MMO, SIS, and SFS were significantly improved during each period, except the period from the $8^{th}$ to $10^{th}$ visit. MFIQ score was significantly improved during the period from the $1^{st}$ to $10^{th}$ visit. In the 5-point Likert scale, the results showed a high patient satisfaction with the treatment. Conclusion: These results showed that functional cerebrospinal therapy using an accurate balancing appliance, may be useful for reducing the symptoms of temporomandibular disorder.

• 융합신호처리학회논문지
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• 제21권1호
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• pp.21-28
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• 2020

본 논문에서는 새로운 형태의 전동 외발 손수레를 제안하였다. 제안된 전동 외발 손수레는 작업 동작을 감지하여 작업자의 의도에 따라 안전하고 균형을 잃지 않도록 하면서 자동으로 외발 손수레를 이동시킬 수 있도록 해 준다. 작업자가 손수레의 손잡이를 잡고 위 아래로 기울이면 외발 손수레에 장착된 방위각 센서를 이용하여 전후 방향의 각도인 피치각을 감지하고 이를 전후진 이동 의도로 간주하여 각도의 크기에 비례하는 속력으로 손수레의 바퀴를 가감속 제어하여 전후진시킨다. 또한 기존 손수레와 달리 적재함에도 추가의 자유도를 부가하여 회전할 수 있도록 하였고, 작업 중 손수레가 좌우 방향으로 기울어질 때 기울기인 롤각을 감지하고 이를 기반으로 하여 적재함이 항상 지면과 수평을 유지할 수 있도록 위치 제어하여 작업자가 손수레의 균형을 잃지 않고 안전하고 쉽게 손수레를 운전할 수 있도록 해 준다. 농업 현장이나 산업 현장에서 실제로 사용할 수 있도록 DC 모터와 인휠모터, 모터 드라이버, 2축 방위각 센서와 저가의 마이크로 컨트롤러를 사용하여 경제적이고 효율적인 제어 시스템을 구성하고 기구부 설계 제작도 수행하였다. 또한 피치각의 변화만 있는 경우, 롤각의 변화만 있는 경우, 그리고 피치각과 롤각이 동시에 변화하는 경우에 대한 실험을 통해 개발된 전동 외발 손수레의 안정성과 유용성을 검증하였다.