• 대한영양사협회학술지
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• 제10권3호
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• pp.322-332
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• 2004

The possibility that high, long-term intake of carbohydrates that are rapidly absorbed as glucose may increase the risk of type 2 diabetes has been long-standing controversy. A high consumption of carbohydrates with a high glycemic index produces greater insulin resistance than did the intake of low glycemic index carbohydrates. This study was designed to evaluate the cabohydrate intake status include glycemic index and correlation carbohydrtae intake status with anthropometry factors & other nutrients in usual diet of the Korean type 2 diabetes mellitus. In 104 tpye 2 diabetes mellitus patients(mean age : 51.8yr, male=44.femal=60), we determined carbohydrte intake status include glycemic index with 24hr recall method and measured anthropometry. Mean daily carbohydrtae intakes and glycemic index were 307.3g(male 323.1g, female 295.5g) and 90.7(male 93.4, female 88.8), respectively. We found a strong and statistically significant association between carbohydrate ratio and glycemic index in obese factors, other nutrient. But carbohydrate intake/kg of body weight was low a significant differences in obese factors, other nutrient. Also glycemic index was effected by total energy intake and carbohydrate ratio than carbohydrate intake/kg of body weight. In conclusion, emphasis for dietary modification should be total energy intake and carbohydrate ratio in diabetes mellitus patient.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1998년도 학술발표회 발표논문집
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• pp.217-223
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• 1998

This study was performed to figure out water consumption of the twisted sweet pepper in a greenhouse. Obtained results are as follows; 1. The ambient temperature was nearly same as the normal year, while the average air temperature and the relative humidity in the green house were little bit higher than those of the outside condition. The transparency of the greenhouse roof was approximately 50%. The total amount of rainfall during the irrigation period was 1,040㎜ which is 350㎜ higher than 1997 during the same period. 2. In case of pot cultivation, as the saturation ratio was increased, the aeaf area and plant height and yield were also increased. The yield from the field cultivation was higher than the average yield from the pot cultivations which are treated by three levels of saturation ratio. 3. The variation of daily consumptive use of the twisted sweet pepper was very large in it's range. In case of the pot cultivation, as the saturation was increased, the daily and the total consumptive use were increased. 4. The daily consumptive use was strongly correlated with the ambient temperature, while it was weakly correlated with the relative humidity and solar radiation. 5. There were close correlation between plant environment; leaf area, plant height and yield, and consumptive use. As the saturation ratio was increased, the correlation between those plant factors and consumptive use was getting stronger.

• International Journal of Naval Architecture and Ocean Engineering
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• 제9권6호
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• pp.693-704
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• 2017

Blended-Wing-Body Underwater Glider (BWBUG), which has excellent hydrodynamic performance, is a new kind of underwater glider in recent years. In the shape optimization of BWBUG, the lift to drag ratio is often used as the optimization target. However this results in lose of internal space. In this paper, the energy reserve is defined as the direct proportional function of the internal space of BWBUG. A motion model, which relates gliding range to steady gliding motion parameters as well as energy consumption, is established by analyzing the steady-state gliding motion. The maximum gliding range is used as the optimization target instead of the lift to drag ratio to optimizing the shape of BWBUG. The result of optimization shows that the maximum gliding range of initial design is increased by 32.1% though an Efficient Global Optimization (EGO) process.

• 전기학회논문지
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• 제65권4호
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• pp.539-546
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• 2016

With the growing interest of microgrid systems all over the world, many studies on microgrid operation are being carried out. The battery energy storage system(BESS) and the diesel generator are key equipments in the microgrid. In this paper, we analyze the characteristics of fuel consumption according to the power ratio of the diesel generator. Then, the formula to represent the unit cost of generation according to the power ratio of the diesel generator is derived. A new modeling of battery operation is presented considering the lifetime reduction according to increasing the cycles of charge/discharge operation of the battery. The methodology of determining the optimal operation of the battery and the diesel generator is presented by the use of the formula of fuel consumption of the diesel generator and the new modeling of battery operation. It is shown that this optimization methodology can be applied effectively for economical operation of the BESS and the diesel generator of a microgrid by case studies.

• Journal of Advanced Marine Engineering and Technology
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• 제31권1호
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• pp.44-50
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• 2007

Diesel engines have high thermal efficiency, and they have less CO & HC emissions than another engines. while NOx & Soot emissions are very much. compared with exhaust emission standards. However, the limit level is more and more strengthened yearly due to the importance of environmental protection. So, the optimal countermeasures for the reduction of NOx & Soot emissions below limit level are required. Therefore. the author has investigated the effects of emulsified fuel on the characteristics of exhaust emissions. using an four-cycle, four-cylinder and direct injection diesel engine because the using of emulsified fuel among various methods for reducing NOx & Soot emissions is simple in installation low in cost and high in efficiency. The results of investigation according to various operating conditions are as follows : 1) Specific fuel consumption increase maximum 19.8% at low load. but is not affected at full load. 2) In case of emulsion ratio 25%, NOx emission decrease 32% at 75% load. 30% at full load. 3) In case of emulsion ratio 25%, Soot emission decrease 84% at 75% load, 59% at full load.

• 설비공학논문집
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• 제27권3호
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• pp.113-122
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• 2015

HVAC&R systems account for more than 50% of the energy consumption of buildings. The purpose of this study is to propose an optimal design method for the HVAC&R system and to examine the possibility for the energy conservation of a selected system. The energy demand for cooling and heating is determined by using TRNSYS and HEET. By an interaction between total system efficiency and cooling-to-heating load ratio, the optimal HVAC&R systems will be decided. The results showed that this proposed method is significantly capable of determining optimal system and building design for saving energy.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권7호
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• pp.3393-3412
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• 2017

As a main challenge in network virtualization, virtual network embedding problem is increasingly important and heuristic algorithms are of great interest. Aiming at the problems of poor correlation in node embedding and link embedding, long distance between adjacent virtual nodes and imbalance resource consumption of network components during embedding, we herein propose a two-stage virtual network embedding algorithm NA-PVNM. In node embedding stage, resource requirement and breadth first search algorithm are introduced to sort virtual nodes, and a node fitness function is developed to find the best substrate node. In link embedding stage, a path fitness function is developed to find the best path in which available bandwidth, CPU and path length are considered. Simulation results showed that the proposed algorithm could shorten link embedding distance, increase the acceptance ratio and revenue to cost ratio compared to previously reported algorithms. We also analyzed the impact of position constraint and substrate network attribute on algorithm performance, as well as the utilization of the substrate network resources during embedding via simulation. The results showed that, under the constraint of substrate resource distribution and virtual network requests, the critical factor of improving success ratio is to reduce resource consumption during embedding.

• 한국유체기계학회 논문집
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• 제15권5호
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• pp.27-31
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• 2012

Turbine inlet temperature is steadily increasing to achieve high specific thrust and efficiency of gas turbine engines. Turbine cooling technology is essential to increase turbine inlet temperature. For this study, a small or medium sized aircraft engine of 10,000 lbf class with the turbine inlet temperature of $1,400^{\circ}C$, the engine overall pressure ratio of 32.2, and the bypass ratio of 5 was set as the baseline model and its performance analysis was performed at the design point. The engine has the performance of 10,013 lbf thrust and the specific fuel consumption of 0.362 lbm/hr/lbf. The thrust and the specific fuel consumption of the baseline model were compared with those of similar class engines. Based on these results, the turbine design requirements were assigned. In addition, the parametric analysis of the engine, related to aerodynamic and cooling design of the high pressure turbine, was performed. Based on the baseline model engine, the influence of turbine inlet temperature, cooling flow ratio, and high pressure turbine efficiency variations on the engine performance was analyzed.

• 유공압시스템학회논문집
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• 제4권1호
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• pp.18-24
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• 2007

The continuously variable transmission (CVT) of which speed ratio can change continuously in a fixed range has the benefits of low fuel consumption and exhaust gas because it enables the engine of a vehicle to operate in a high efficiency range regardless of vehicle speed. The speed ratio of belt type CVT is controlled by adjusting line pressure. The one of the line pressure control methods, mechanical-hydraulic control is usually adopting VDT's control method, in which the secondary solenoid valve has two functions both a regulator and a line pressure controller. However, this control method could not show the high performance of CVT with optimal driving capability because of the limitation of simple control algorithm, and it could not gain market share sufficiently in spite of the advantage of CVT with low fuel consumption. On the other hand, the electro-hydraulic control method gives the enhancement of power performance and low fuel consumption by implementing various driving mode using the proportional control or PWM control. The key of CVT technique is to develop a control algorithm of the electro-hydraulic solenoid valve in order to implement the speed ratio efficiently. In this paper, the line pressure control algorithm is proposed and the hydraulic system is controlled using metal belt type CVT test rig and the embedded ECU platform.

• 자원환경지질
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• 제23권3호
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• pp.309-322
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• 1990

지난 20년간(年間) 한국경제(韓國經濟)의 지속적(持續的)인 산업발전(産業發展)은 광물자원(鑛物資源)의 대량소비시대(大量消費時代)를 이룩하였다. 그러나 이와 같은 소비(消費)의 급성장(急成長)은 대부분(大部分) 외국(外國)으로부터의 수입(輸入)에 의존(依存)하였다· 한국(韓國)에서는 330여(余) 광종(鑛種)이 알려져왔으며, 그중에서 50여종(種)이 산업원료(産業原料) 광물자원(鑛物資源)으로 이용(利用)되고 있다. 1988년(年) 연료광물자원(燃料鑛物資源)을 제외(除外)한 전체(全體) 금속(金屬) 비금속(非金屬) 원료광물자원(原料鑛物資源)의 국내(國內) 자급도(自給度)는 29% 였고, 26종(種)의 비금속(非金屬) 광물(鑛物)은 그 자급도(自給度)가 66%로 비교적(比較的) 높은 편이나, 18종(種)의 금속광물(金屬鑛物)의 경우는 그 자급도(自給度)가 6.3%에 불과한 실정(實情)이다. 1970년대(年代) 이후(以后) 우리나라의 경제발전(經濟發展) 단계에서 국민총생산량(國民總生産量)과 광물소비(鑛物消費)와의 관계는 아주 완만한 변화양상(變化樣狀)을 보이고 있다.