• 제목/요약/키워드: maintain

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간헐적 단식의 임상적 적용 (Clinical Implications of Intermittent Fasting)

  • 조윤정
    • 비만대사연구학술지
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    • 제1권1호
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    • pp.26-32
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    • 2022
  • Dietary therapy is one of the most important treatments for obesity. In general, it is difficult to maintain the recommended diet for weight control for a long time; therefore, it is difficult to achieve weight loss or maintain weight. Intermittent fasting has recently become one of the most popular diets for weight loss. Intermittent fasting is a strategy of repeating intermittent energy restriction and eating, unlike conventional diets of continuous calorie restriction. Studies on intermittent fasting have shown positive results not only in terms of weight loss but also improvement in metabolic indicators, such as glucose control and reduction of blood pressure. Therefore, it is important to maintain a long-term dietary strategy to prevent weight loss in obese individuals. The effect on weight loss was similar to that of an existing continuous energy-restricted diet. However, long term studies and safety data are still lacking, and large-scale studies with various populations are needed. If more evidence is secured for various individuals, it can be expected that intermittent fasting, including time-restricted eating, will be applied clinically in the future.

최적화 기법을 이용한 초저고도 운용위성 연료량 분석 (Fuel Optimization for Low Earth Orbit Maintenance)

  • 박용재;박상영;김영록;최규홍
    • Journal of Astronomy and Space Sciences
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    • 제25권2호
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    • pp.167-180
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    • 2008
  • 지구관측 영상위성의 해상도는 위성에 장착된 광학카메라의 Field of View(FOV)와 위성의 임무고도에 의해 결정된다. 따라서 카메라의 FOV가 고정된 경우 해상도를 향상시키는 방법은 위성의 임무고도를 낮추는 것이다. 하지만 저고도일수록 대기저항에 의한 위성의 고도감소가 크게 나타나고 이를 보정하기 위해 많은 연료가 필요하게 된다. 이 연구에서는 초저고도에 있는 위성의 임무도 유지를 위하여 필요한 연료량 산출을 분석하고자 한다. 이를 위해 지구와 위성 간 2체 문제에 대기저항과 이를 보정하기 위만 주력을 고려하여 운동방정식을 세우고, Legendre-Gauss-Lobatto(LGL) points를 이용한 collocation method를 사용하였다. 지속적으로 임무고도를 유지하는 경우와 고도 상승하강 기동을 하여 임무고도를 대략 유지하는 경우에 대한 소모되는 연료량을 비하였다. 고도 상승하강 기동의 방법이 임무고도를 유지하기 위하여 더 적은 연료를 소모하였다. 고도 상승하강 기동방법을 이용할 때 고도상승의 주기 변화로 얻어지는 연료이득은 작고, 태양활동 시기나 위성의 임무고도변화는 연료 사용에 큰 영향을 끼치는 것을 확인할 수 있었다. 또한 여러 가지 조건에 대한 연료소모량을 구체적으로 제시하였다. 이 연구를 통해서 얻어진 알고리즘은 위성의 저고도 유지를 위한 연료량을 산정하는데 많은 도움이 될 것이며, 임무도 설정에 있어서도 원하는 해상도와 연료량을 고려하여 최상의 선택을 할 수 있는 자료를 제공할 수 있다.

냉혈 Potassium 심정지액을 이용한 심근보호의 실험적 연구 (The Experimental Study of Myocardial Protection Byusing Cold Blood Potassium Cardioplegia in Open Heart Surgery)

  • 이동준
    • Journal of Chest Surgery
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    • 제13권3호
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    • pp.186-197
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    • 1980
  • We attempted to evaluate the effectiveness of cold blood potassium cardioplegia [Group B] compared with that of intermittent aortic cross clamp with topical hypothermia [Group A] in each six dogs. The studies were performed under the extracorporeal circulation with moderate hypothermia by using Mongrel dogs. 1. In Group A [6], it was difficult to maintain the temperature below 20?. but in Group B [6], it was possible to maintain the temperature. 2. In blood pressure and myocardial recovery ability, Group B was more excellent than Group A. 3. There was no significant difference in Na+, Ca++ and Cl- between both groups, but in K+ level, Group A was mild decreased and Group B was nearly normal level. 4. In serum LDH level, Group A was higher than Group B, but in SGOT level there was no significance between both groups. 5. On electromicroscopical study, Group A showed severe change in mitochondria, but Group B was nearly normal view. Thus we suggest that cold blood potassium cardioplegia would be more effective than intermittent aortic cross clamp with topical hypothermia for myocardial protection in open heart surgery.

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An Adaptive Reclosing Algorithm Considering Distributed Generation

  • Seo, Hun-Chul;Kim, Chul-Hwan
    • International Journal of Control, Automation, and Systems
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    • 제6권5호
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    • pp.651-659
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    • 2008
  • Autoreclosing techniques have been used in power systems to maintain system stability and continuity of supply. Environmental and economical issues have driven significant increases in the development of distributed generation (DG). DG connected to distribution systems, however, may impose negative influences with respect to power quality, protection, and stability, because DG can cause some challenges to protection, especially to reclosing. For this reason, in order to improve the reliability and safety of the distribution system, the rules and guidelines suggest that the DG system needs to be rapidly disconnected from the system before reclosing. We present, in this paper, an adaptive reclosing algorithm considering the DG. The algorithm consists of an angle oscillation's judgment, the emergency extended equal-area criterion (EEEAC), the calculation of an optimal reclosing time, and a reconnection algorithm. Our simulation results for three different DG technologies with Electromagnetic Transient Program (EMTP) indicate that we can maintain transient stability while the DG is protected against disturbances.

IETM의 변환절차와 IETMDB구축에 대한 연구 (A Study on IETM Conversion procedure and IETMDB Construction)

  • 김철환;이정환
    • 한국전자거래학회지
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    • 제1권2호
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    • pp.1-25
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    • 1996
  • This study aims to provide conversion process to acquire IETM and fundamental IETMDB construction necessary for IETM. As the weapon system and other equipments are highly advanced and electronically sophisticated, the amount of information necessary to operate and maintain the systems is being dramatically increased. Thus, it is theoretically and practically impossible to maintain the huge amount of information in the paper-based manual. Furthermore, the vast amount of paper based-technical information makes it difficult to share them in real time. This paper discuss how to solve these prolems by using highly advanced information technology such as network, database, data communication, etc First, we propose an effective conversion process for the decision of IETM classes from Class 1 to Class 5. Second, we also propose a construction of IETMDB and IETM system by using CALS standard and Content Data Model (CDM).

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중족골통에서의 소족지 중족 절골술 (Lesser Metatarsal Osteotomies for Metatarsalgia)

  • 이승열;정진화
    • 대한족부족관절학회지
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    • 제21권3호
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    • pp.83-87
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    • 2017
  • Metatarsalgia means the pain under the lesser metatarsal heads. The many causes of metatarsalgia can be categorized into three groups: local disease in the region, altered forefoot biomechanics, and systemic disease affecting the region. Surgical options need to be considered if nonsurgical treatment fails. The metatarsal osteotomies are designed primarily to reduce the weightbearing forces on the metatarsal head by elevating or shortening the metatarsal. Many lesser metatarsal osteotomies have been described, and their success depends on many factors. Regardless of the method employed, it is important to maintain or restore the metatarsal cascade to maintain an even pressure under the lesser metatarsal heads and prevent transfer lesions. The surgeon must understand the effects of the metatarsal osteotomy on the forefoot patho-biomechanics and decide, using a combination of clinical examinations and imaging, whether the desired effect of the osteotomy is to shorten or elevate the metatarsal head or both.

Design of Tissue-Transfer Container Using Thermoelectric Element Module

  • Park, Yong Pil;Cheon, Min-Woo
    • Transactions on Electrical and Electronic Materials
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    • 제18권2호
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    • pp.66-69
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    • 2017
  • The internal temperature of human-tissue transfers must be steadily maintained regardless of the external environmental changes. An ice pack and dry ice are the coolants for the transfer containers for which heat-insulating materials such as EPP (expended polypeopylene and EPS (expended polystrene) are used; however, changes of the external temperature/pressure and the melting of the coolants that is due to a long carriage result in changes of the internal temperature, and this makes it difficult to maintain the temperature. Accordingly, the thermoelectric element was used to design/manufacture a transfer container to maintain the internal temperature regardless of the external environmental changes. As a result of the measurement of the changes of the internal temperatures of the manufactured thermoelectric-element container and the EPS container over time, the internal temperature of the EPS container was increased, whereas the internal temperature of the thermoelectric-element container was maintained. The temperature of the distilled water that was poured into the containers indicated a pattern identical to that of the internal temperature.

넓은 부하범위에서 고효율 특성을 갖는 역율개선회로의 PWM 제어기 (PWM Controller of Power Factor Correction Circuit to Improve Efficiency for Wide Load Range)

  • 손민수;김홍중;박귀철;최재호
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2016년도 전력전자학술대회 논문집
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    • pp.75-76
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    • 2016
  • This paper proposes a power factor correction circuit with a high efficiency over a wide load range characteristics for a communication power supply. And the characteristic verification is applied to produce a design of prototype. Power factor correction circuit can reduce conduction losses by applying Bridgeless Boost Converter for efficiency. Over a wide load range to maintain the efficient, the control method of a PWM controller is divided by two sections according to the load area. In the low-load region, it was reduced switching losses by applying the critical conduction mode control method. On the other hand, in the heavy-load area, the hysteresis current control method is used to maintain the high efficiency over a wide load range by limiting the peak noise of the inductor.

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선삭에서 일정 절삭력 유지를 위한 구속 적응제어에 관한 연구 (A Study on the Application of Adaptive Control Constraint to Maintain Constant Cutting force in Turning)

  • 김인수;황홍연;김광준
    • 대한기계학회논문집
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    • 제10권3호
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    • pp.376-382
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    • 1986
  • 본 연구에서는 절삭과정의 정적특성에 관한 식과 그에 포함된 계수를 실험을 통하여 결정함으로써 절삭과정을 모델링하고, 절삭시에 검출되는 주절삭력에 따라 이 송속도를 제어하며 절삭과정의 변동에 관계없이 시스템의 안정을 보장하는 제어 프로 그램 및 제어장치를 개발하여 선삭작업에 응용하여 보고자 한다.