• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1999년도 춘계 학술발표회 논문집
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• pp.185-191
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• 1999

An air-conditioning system based on the chemical heat storage principle was considered. $H_2O$ was chosen as the reaction gas and the working fluid as well. Na$_2$S, CaCl$_2$, MnCl$_2$, BaCl$_2$, MgCl$_2$, Fe$_2$(SO$_4$)$_3$ and MnSO$_4$ were tested as the solid reactants by using Cahn pressure balance. Na$_2$S was superior to other salts in respect of high capability of absorption of water gas, 5 moles of $H_2O$ per unit mole of Na$_2$S, and adequate temperature of adsorption, $65^{\circ}C$ at 7torr, and of desorption, 13$0^{\circ}C$ at 76torr. Clausius-Clapeyron diagram of Na$_2$S was obtained via adsorption experiments at several vapor pressures of water gas. To enhance heat and mass transfer characteristics, usually below 1W/m K, of the reactor bed of general adsorption systems, expanded graphite block was adapted as the support of Na$_2$S salt. Expanded graphite blocks had thermal conductivity values of 20~80W/mK with respect to 100~400kg/㎥ of block bulk density. Permeability values of expanded graphite blocks were 10$^{-13}$ ~ 10$^{-14}$ $m^2$ with respect to 100~300kg/㎥ of block bulk density showing highly decreasing values of permeability, below 10$^{-l4}$$m^2$, in the range of above 150kg/㎥ of block bulk density.y.

• 동의생리병리학회지
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• 제26권5호
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• pp.630-640
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• 2012

Recently, the range of meridian muscle has expanded to muscular membranes, tendons and sinews as well as muscles, comprehending the modern manual therapy and its theories. So, in this study, the movement of body is explained through the assignment of meridian muscles into 3 Yins and 3 Yangs, and the modern manual therapy is understood with body's movement principles rather than with simple muscular movements. For this, the ground that the meridian muscles can expand to muscular membranes, tendons and sinews is researched in newest papers and studies rather than in the conventional studies that have analyzed the meridian muscles just in anatomic viewpoints. And, to find out how it can be applied to the actual clinic, its relationship with modern manual therapies such as Positional Release Therapy and Muscle Energy Techniques which are in the spotlight lately is also researched, getting the following results: Modern manual therapy is to keep the mutual balance of Yin-Yang meridian muscles after all and secure the stability of body to relieve the pains due to the stagnation of energy and blood. In the main body, they can be allotted into the opening of Great Yang/Great Yin, the closing of Bright Yang(陽明)/Small Yin, and the pivoting of Small Yang/Growing Yin (厥陰). The bending and stretching of meridian muscles as well as the movement of body can be explained according to the principle of opening, closing and pivoting. When the body is divided into 3 Yins and 3 Yangs, the viewpoint of Yin-Yang-Inside-Outside can be applied to the protagonist and antagonist muscles, giving a theoretic basis to the modern manual therapy. In the process to understand Positional Release Therapy and Muscle Energy Techniques in the viewpoint of Meridian Muscle, it turned out that the meridian muscle theory of Oriental Medicine which used to be known only in documents can well explain the movement mechanism of human body. The stress reaction through the reciprocal inhibition in Positional Release Therapy and Muscle Energy Techniques can also be understood with Yin-Yang-Inside-Outside.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 1999년도 제13회 학술강연논문집
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• pp.33-33
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• 1999

The Coanda effect is the tendency for a fluid jet to atach itself to an adjacent surface and follow its contour without causing an appreciable flow separation. The jet is pulled onto the surface by the low pressure region which develops as entrainment pumps fluid from the region between the jet and the surface. Then the jet is held to the wall surface by the resulting radial pressure gradient which balance the inertial resistance of the jet to turning. The jet may attach to the surface and may be deflected through more than 180 dog, when the radius of the Coanda surface is sufficiently large compared to the height of the exhaust nozzle. However, if the radius of curvature is small, the jet turns through a smaller angle, or may not attach to the surface at all. In general, the limitations in size and weight of a device will limit the radius of the deflection surface. Thus much effort has been paid to improve the jet deflection in a variety of engineering fields. The Coanda effect has long been applied to improve aerodynamic characteristics, such as the drag/lift ratio of flight body, the engine exhaust plume thrust vectoring, and the aerofoil/wing circulation control. During the energy crisis of the seventies, the Coanda jet was applied to reduce vehicle drag and led to drag reductions of as much as about 30% for a trailer configuration. Recently a variety of industrial applications are exploiting another characteristics of the Coanda jets, mainly the enhanced turbulence levels and entrainment compared with conventional jet flows. Various industrial burners and combustors are based upon this principle. If the curvature of the Coanda surface is too great or the operating pressure too high, the jet flow will break away completely from the surface. This could have catastrophic consequences for a burner or combustor. Detailed understanding of the Coanda jet flow is essential to refine the design to maximize the enhanced entrainment in these applications.

• Journal of Power Electronics
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• 제17권4호
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• pp.1037-1047
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• 2017

The Differential Power Processing (DPP) converter is a promising multi-module photovoltaic inverter architecture recently proposed for photovoltaic systems. In this paper, a DPP converter architecture, in which each PV-panel has its own DPP converter in shunt, performs distributed maximum power point tracking (DMPPT) control. It maintains a high energy conversion efficiency, even under partial shading conditions. The system architecture only deals with the power differences among the PV panels, which reduces the power capacity of the converters. Therefore, the DPP systems can easily overcome the conventional disadvantages of PCS such as centralized, string, and module integrated converter (MIC) topologies. Among the various types of the DPP systems, the feed-forward method has been selected for both its voltage balancing and power transfer to a modified H-bridge inverter that needs charge balancing of the input capacitors. The modified H-bridge multi-level inverter had some advantages such as a low part count and cost competitiveness when compared to conventional multi-level inverters. Therefore, it is frequently used in photovoltaic (PV) power conditioning system (PCS). However, its simplified switching network draws input current asymmetrically. Therefore, input capacitors in series suffer from a problem due to a charge imbalance. This paper validates the operating principle and feasibility of the proposed topology through the simulation and experimental results. They show that the input-capacitor voltages maintain the voltage balance with the PV MPPT control operating with a 140-W hardware prototype.

• 전력전자학회논문지
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• 제26권2호
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• pp.82-89
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• 2021

This study proposes a DAB two-stage series structure with insulated bidirectional DC-DC converter for two-way power transfer between the renewable energy of high voltages (1 kV and above). The proposed circuit transforms the existing DAB converter into a two-stage series structure to reduce the pressure in the switch. The problem of power imbalance occurring in the design of the DAB converter second-stage series is improved by applying the cell balancing method circuit and the common mode coupled inductor using an external flying capacitor instead of reflecting the existing improvement measures, voltage balance control, and inductor current control. In addition, a no-load supercharging sequence is proposed in high voltages and high-speed switching by using the fixed duty output method. This study presents the analysis results through the structure of the proposed circuit, the principle of improving the power imbalance problem, and simulations. Prototypes were manufactured to meet the specifications of input/output voltage of 1700 V, maximum load of 65 kW, and switching frequency of 51kHz, and the validity of the topology was verified using the experimental results and efficiency data.

• 유통과학연구
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• 제10권7호
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• pp.33-41
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• 2012

The purpose of this study is to analyse the state of the energy industry and to determine the efficiency of its functioning on the basis of energy conservation principle and application of innovative technologies aimed at improving the ecological modernisation of agricultural sectors of Kazakhstan. The research methodology is based on an integrated approach of financial and economic evaluation of the effectiveness of the investment project, based on calculation of elasticity, total costs and profitability, as well as on comparative, graphical and system analysis. The current stage is characterised by widely spread restructuring processes of electric power industry in many countries through introduction of new technical installations of energy facilities and increased government regulation in order to enhance the competitive advantage of electricity market. Electric power industry features a considerable value of creating areas. For example, by providing scientific and technical progress, it crucially affects not only the development but also the territorial organisation of productive forces, first of all the industry. In modern life, more than 90% of electricity and heat is obtained by Kazakhstan's economy by consuming non-renewable energy resources: different types of coal, oil shale, oil, natural gas and peat. Therefore, it is significant to ensure energy security, as the country faces a rapid fall back to mono-gas structure of fuel and energy balance. However, energy resources in Kazakhstan are spread very unevenly. Its main supplies are concentrated in northern and central parts of the republic, and the majority of consumers of electrical power live in the southern and western areas of the country. However, energy plays an important role in the economy of industrial production and to a large extent determines the level of competitive advantage, which is a promising condition for implementation of energy-saving and environmentally friendly technologies. In these circumstances, issues of modernisation and reforms of this sector in Kazakhstan gain more and more importance, which can be seen in the example of economically sustainable solutions of a large local monopoly company, significant savings in capital investment and efficiency of implementation of an investment project. A major disadvantage of development of electricity distribution companies is the prevalence of very high moral and physical amortisation of equipment, reaching almost 70-80%, which significantly increases the operating costs. For example, while an investment of 12 billion tenge was planned in 2009 in this branch, in 2012 it is planned to invest more than 17 billion. Obviously, despite the absolute increase, the rate of investment is still quite low, as the total demand in this area is at least more than 250 billion tenge. In addition, industrial infrastructure, including the objects of Kazakhstan electric power industry, have a tangible adverse impact on the environment. Thus, since there is a large number of various power projects that are sources of electromagnetic radiation, the environment is deteriorated. Hence, there is a need to optimise the efficiency of the organisation and management of production activities of energy companies, to create and implement new technologies, to ensure safe production and provide solutions to various environmental aspects. These are key strategic factors to ensure success of the modern energy sector of Kazakhstan. The contribution of authors in developing the scope of this subject is explained by the fact that there was not enough research in the energy sector, especially in the view of ecological modernisation. This work differs from similar works in Kazakhstan in the way that the proposed method of investment project calculation takes into account the time factor, which compares the current and future value of profit from the implementation of innovative equipment that helps to bring it to actual practise. The feasibility of writing this article lies in the need of forming a public policy in the industrial sector, including optimising the structure of energy disbursing rate, which complies with the terms of future modernised development of the domestic energy sector.

• 자원ㆍ환경경제연구
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• 제18권4호
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• pp.587-635
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• 2009

본 연구의 목적은 Post-2012 의무부담에 대한 경제적 파급효과 분석을 위해 글로벌 동태연산기능일반균형모형(Global Dynamic Computable General Equilibrium Model : Global CGE Model)을 개발하는 것이다. 즉, 본 모형을 통해 우리나라의 의무부담 증가에 따라서 국제 배출권거래시장과 GNP, 소비, 투자, 수 출입 등 거시경제 변수들에 미치는 영향을 살펴보고자 한다. 기존 연구와는 달리 본 모형은 전 세계를 주요 경제그룹으로 나누어 분석한 글로벌모형으로서 주요 국가의 거시경제지표를 모두 반영하고 있으며, 이론적으로는 내생적 경제성장이론을 적용하고, 정책적으로는 배출권거래제도와 탄소세 등을 반영하고 있다. 특히 외생적인 기술진보를 모형에 반영하였다. 본 분석에 의하면, 온실가스 감축이 강화될수록 경제에 미치는 악영향이 커진다는 것을 알 수 있으며 거시경제지표 중에 무역수지의 감소가 가장 크게 나타나고 그 다음으로 투자 소비의 감소율이 큰 것으로 나타났다. 특히 산업별로는 에너지 의존도가 큰 에너지 다소비 업종일수록 온실가스 감축 영향이 크게 나타난다. 그리고 현재 개발도상국의 지위를 부여받고 있는 한국이 온실가스 감축 의무부담을 받으면 상대적으로 중국 등 다른 개발도상국들은 이득을 본다.

• Journal of Nutrition and Health
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• 제55권1호
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• pp.10-20
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• 2022

2020 한국인 영양소 섭취기준 개정에서 단백질은 기본적으로 질소평형을 유지하는데 필요한 단백질 양 0.66 g/kg 체중/일에 이용효율 90%를 적용한 평균필요량 0.73 g/kg 체중/일과 변이계수 12.5%를 적용한 권장섭취량 0.91 g/kg 체중/일을 생애주기별 체위기준치 변화에 따라 제시하였다. 그러나 성장기의 단백질 섭취기준에서는 체중 기준을 2017년에 개정된 소아청소년 성장도표에 근거하고, 일본 DRI 자료를 참고로 단백질 식품 이용효율을 차등 적용하였으며, WHO/FAO/UNU 보고서상의 성장에 필요한 단백질량 오류를 수정·반영하여 기준값을 개정하였다. 그 결과 일부 연령구간에서 섭취기준의 상향조정이 있었으나 한국인의 연령대별 1일 평균 단백질 섭취량은 대부분의 연령대에서 단백질 평균필요량의 100%를 넘는 것으로 나타났고, 남자 75세 이상과 여자 65세 이상을 제외하고는 권장섭취량과 비교했을 때도 많은 것으로 나타나 단백질 섭취기준의 상향 조정은 국민의 평균 단백질 섭취기준을 반영하는 것으로 판단된다. 한편, 75세 이상의 단백질 섭취량은 근감소증 예방, 근력 강화 등을 위해 65-74세 단백질 섭취기준과 동일하게 설정하였다. 이번 개정에서 단백질 에너지 적정비율은 기존의 7-20%를 유지하였으나 향후 단백질의 적정한 섭취수준 및 만성질환예방을 위한 단백질 필요량 설정에 관한 과학적 근거마련을 위해 우리나라 국민을 대상으로 한 다양한 중재연구가 수행되어야 할 것이다.

• 트랜스-
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• 제8권
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• pp.95-127
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• 2020

본 연구는 태극권 움직임에서 신체의 이완방법을 개발하기 위해 바티니에프 기본원리를 적용하여 태극권 움직임의 원리를 분석하였다. 이 연구과정을 통해 태극권과 바티니에프의 신체 움직임이 일맥상통한다는 것을 알 수 있었다. 첫째, 태극권과 바티니에프의 신체 움직임 철학 각도에서 살펴보면 두 기법의 궁극적인 목표는 모두 정신과 신체의 통합이다. 즉 동양의 심신일원론(心身一元論)과 서양의 신체자각(Body Awareness)이 일맥상통하였다. 둘째, 바티니에프가 제시한 호흡지지의 측면에서 살펴보면 두 기법은 모두 호흡을 통해 신체를 자연스럽게 움직이게 하고 각 부위를 이완시킨다. 태극권에서 기(氣)는 생명의 바탕이며 신(身)의 힘이다. 즉, 태극권의 호흡은 몸과 마음(Body- Mind)을 소통, 조화, 융화시킬 수 있는 것이다. 다시 말해서 태극권의 호흡은 정신적인 융합을 통하여 이루어지며 움직임에 영향을 주었다. 바티니에프의 호흡지지도 마찬가지다. 바티니에프의 호흡은 모든 관점에서 움직임에 영향을 주고 호흡은 몸의 내부와 외부의 형태를 모두 변화시킨다고 한다. 셋째, 바티니에프가 제시한 중심부지지의 측면에서 살펴보면 두 기법은 모두 중심을 강조하였다. 중심 지지를 의식하면서 움직이면 몸의 표면적인 근육보다는 좀 더 깊은 근육을 사용할 수 있으며 이를 통해 강하고 유연한 움직임을 가능하게 하였다. 태극권의 기침단전(氣沉丹田)은 의식적으로 복식호흡을 사용하고 힘을 중심으로 모은다. 이러한 운동을 할 때 중심은 더 안정되고 호흡 역시 순조로워진다. 넷째, 바티니에프 기본원리에서 제시한 회전적 요인의 측면에서 살펴보면 모두 회전을 사용한 움직임을 통해 신체 이완이라는 목적을 이루게 된다. 바티니에프의 회전적 요인은 축을 중심으로 3차원적으로 움직이는 관절운동이라는 특성을 인지함으로써 동작을 더욱 쉽게 하고 자유롭게 할 수 있었다. 태극권도 마찬가지다. 태극권은 원형과 나선형(Spiral Movement)의 움직임을 통해서 공간을 최대한 접근하고 매끄럽게 흐름을 전환해서 이완이라는 목적을 이루게 되었다. 다섯 번째, 코헨(Bonnie Bainbridge Cohen)의 Body-Mind Centering Work 이론을 토대로 바티네에프가 정립한 발달 모형의 각도에서 살펴보면 태극권의 움직임의 발전과정과 발달 모형에서 제시한의 호흡, 중심-말초부 연결 / 중앙 반사, 머리- 꼬리뼈 연결 / 척추의 움직임, 상체-하체 연결 / 상응하는 움직임, 신체의 반쪽 연결 / 동종 편측 연결, 교차 측면 연결 / 대측 연결 모두 일맥상통함을 알 수 있었다. 즉 태극권은 호흡을 통해 에너지를 중심으로 모으고, 요추를 통해 상체와 하체를 연결하며 움직임이 발전할 때 동종 편측 연결뿐만 아니라 교차 측면 연결을 할 수 있다. 이러한 연구를 통해 무용의 움직임을 자연스럽게 표현하고, 신체 자각을 토대로 중심축과 관절, 및 균형을 이용한 신체의 움직임 원리를 분석해낼 수 있었다.

• 동양고전연구
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• 제33호
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• pp.31-56
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• 2008

여헌 장현광은 조선시대 여타의 유학자에 비해 철저하게 성리학의 본질을 충실하게 탐구하고, 심도 있게 학설을 확장시킨 학자이다. 여헌은 성리학적 교육의 기본 체계인 "대학"과 "중용"에 의거하여 자신의 학설을 강화한다. 이러한 사유의 전개에 근거하여 여헌의 교육사상은 세 측면에서 조명해 볼 수 있다. 첫째, 여헌은 교육의 기준으로서 성인군주론(聖人君主論)을 심화한다. 그것은 본질적으로 존천리알인욕(存天理?人欲)을 추구하며, 도덕적 각성과 덕치주의를 강조한다. 둘째, 여헌은 교육의 양식으로서 성경(誠敬)의 공부론을 강조한다. 여헌은 마음에 성(誠)과 경(敬)을 세울 것을 강조하고, 두 가지의 차별성을 인정하면서도 동일한 맥락에서 이해한다. 셋째, 여헌은 교육의 방법으로서 분합(分合)의 조화를 주창한다. 여헌은 그의 독특한 리기경위설(理氣經緯說)을 통해, 역(易)의 논리에 따라 어느 한쪽으로 치우치거나 지나치지 않는 중용의 관점을 유지한다. 이러한 여헌의 교육적 사유는 현대 교육적 의미에서 볼 때, 교육의 표준을 도덕의 확립에 두고, 교육의 양식과 방법에서 중용적 통찰을 고려하는 아이디어를 제공한다. 요컨대, 여헌의 교육사상은 일관성을 지닌 전통 성리학의 교육적 지혜를 담고 있는데, 현대 교육의 기준 혼란, 내용의 비체계화, 방법적 치우침에 대한 균형 감각의 중요성을 재검토하는 데 주요한 시사점을 준다.