• 한국자동차공학회논문집
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• 제12권5호
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• pp.198-204
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• 2004

Dynamic fracture is investigated in plate applied by impacting bar. Numerical simulations of the experiments are made by using a finite element method(FEM) code, LS-DYNA. The eroding surface-to-surface contact allows between impacting bar and impacted plate. The occurrence of hourglass deformations in an analysis can invalidate results and hourglass energy is minimized to obtain the good accuracy of result. Total, internal and kinetic energies, von Mises plastic stress and X,Y,Z velocities of impacting bar are analyzed in this study.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.376-382
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• 1991

In the analysis of constrained holonomic systems, the Lagange multiplier method yields a system of second-order ordinary differential equations of motion and algebraic constraint equations. Conventional holonomic or nonholonomic constraints are defined as geometric constraints in this paper. Previous works concentrate on the geometric constraints. However, if the total energy of a dynamic system can be computed from the initial energy plus the time integral of the energy input rate due to external or internal forces, then the total energy can be artificially treated as a constraint. The violation of the total energy constraint due to numerical errors can be used as information to control these errors. It is a necessary condition for accurate simulation that both geometric and energy constraints be satisfied. When geometric constraint control is combined with energy constraint control, numerical simulation of a constrained dynamic system becomes more accurate. A new convenient and effective method to implement energy constraint control in numerical simulation is developed based on the geometric interpretation of the relation between constraints in the phase space. Several combinations of energy constraint control with either Baumgarte's Constraint Violation Stabilization Method (CVSM) are also addressed.

• Nuclear Engineering and Technology
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• 제32권6호
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• pp.566-594
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• 2000

In most LMFBR(Liquid Metal Fast Breed Reactor) design, the operating temperature is very high and the time-dependent creep and stress-rupture effects become so important in reactor structural design. Therefore, unlike with conventional PWR, the normal operating conditions can be basically dominant design loading because the hold time at elevated temperature condition is so long and enough to result in severe total creep ratcheting strains during total service lifetime. In this paper, elevated temperature design of the conceptually designed baffle annulus regions of KALIMER(Korea Advanced Liquid MEtal Reactor) reactor internal strictures is carried out for normal operating conditions which have the operating temperature 53$0^{\circ}C$ and the total service lifetime of 30 years. For the elevated temperature design of reactor internal structures, the ASME Code Case N-201-4 is used. Using this code, the time-dependent stress limits, the accumulated total inelastic strain during service lifetime, and the creep-fatigue damages are evaluated with the calculation results by the elastic analysis under conservative assumptions. The application procedures of elevated temperature design of the reactor internal structures using ASME Code Case N-201-4 with the elastic analysis method are described step by step in detail. This paper will be useful guide for actual application of elevated temperature design of various reactor types accounting for creep and stress-rupture effects.

• 한국태양에너지학회 논문집
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• 제30권3호
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• pp.47-54
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• 2010

Recently the researchers has been interested in the development of the high performance windows such as solar control window using automatic shading devices, air-flow window, selective coating window. In order to assess the energy performance of total fenestration system, the net energy gains or losses through the glazings and windows should be evaluated. It depends on the thermal transmittance (U-value) and the total solar energy transmittance (SHGC, g-value). This study aims to measure the solar heat gain coefficient according to the NFRC 201 standard test method. In results, we could find the result of different SHGC of the glazing system with a different slat angles. The SHGC in case of $90^{\circ}$ of internal slat angle with regard to the window surface is about 0.56, that in case of $45^{\circ}$ is about 0.49 and that in case of $0^{\circ}$ is about 0.33. Significant dependence on the solar radiation intensity and incident angle was found in comparison of the measured and simulated SHGC.

• 한국공작기계학회논문집
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• 제16권4호
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• pp.108-112
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• 2007

This study analyzes the dynamic fracture phenomenon that aluminum rod impacts aluminum plate or rigid plate and deforms. The value of von-Mises stress in the instance that aluminum rod deforms on rigid plate after contact becomes 1.3 times as large as that in the instance of contact. On the contrary, the value of von-Mises stress in the instance that aluminum rod goes through aluminum plate after contact becomes 0.7 times as small as that in the instance of contact. The value of internal energy in the instance that aluminum rod contacts aluminum plate becomes 2.3 times as large as that in the instance that aluminum rod contacts rigid plate. But the value of kinetic energy in the instance that aluminum rod contacts aluminum plate becomes 0.9 times as small as that in the instance that aluminum rod contacts rigid plate. The value of internal energy in the instance that aluminum rod goes through aluminum plate after contact becomes 0.7 times as small as that in the instance that aluminum rod impacts rigid plate and deforms. And the value of sliding energy in the instance that aluminum rod contacts aluminum plate becomes 0.2 times as small as that in the instance that aluminum rod contacts rigid plate. The value of total energy in case that aluminum rod impacts aluminum plate becomes 0.9 times as small as that in the case that aluminum rod impacts rigid plate.

• International Journal of Fluid Machinery and Systems
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• 제2권1호
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• pp.80-91
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• 2009

In this study, a prediction theory for specific noise that is the overall characteristic of the fan has been proposed. This theory is based on total pressure prediction and broadband noise prediction. The specific noises of two forward curved fans with different number of blades were predicted. The flow around the impeller having 120 blades (MF120) was more biased at a certain positions than the impeller with 40 blades (MF40). An effective domain of the energy conversion of MF40 has extended overall than MF120. The total pressure was affected by the slip factor and pressure loss caused by the vortex flow. The suppression of a major pressure drop by the vortex flow and expansion of the effective domain for energy conversion contributed to an increase in the total pressure of MF40 at the design point. The position of maximum relative velocity was different for each fan. The relative velocity of MF120 was less than that of MF40 due to the deviation angle. The specific noise of MF120 was 2.7 dB less than that of MF40 due to the difference in internal flow. It has been quantitatively estimated that the deceleration in the relative velocity contributed to the improvement in the overall performance.

• Asian-Australasian Journal of Animal Sciences
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• 제13권5호
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• pp.702-710
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• 2000

A large portion of total energy expenditure associated with ruminant livestock production goes towards maintenance. Approximately 55% of whole body energy use is consumed by visceral tissues (including internal organs) with the majority of this going to the liver and gastrointestinal tract. Muscle and adipose tissues consume about 27% of total body energy expenditure. Metabolic components within the viscera responsible for the majority of energy consumption include ion transport, protein turnover, substrate cycling, and urea synthesis (liver). Within muscle tissue of growing animals ion transport and protein turnover account for most of the energy expenditure. Protein synthesis consumes approximately 23% of whole body energy use and visceral tissues account for proportionally more of whole body protein synthesis than skeletal muscle. Research efforts focused on improving energetic efficiency of the tissues and metabolic mechanisms responsible for the majority of whole animal energy expenditure should provide information leading to more efficient production of an edible product.

• Journal of Nutrition and Health
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• 제26권5호
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• pp.615-624
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• 1993

본 연구는 19세부터 23세까지의 한국과 일본 여대생 108명을 대상으로 체격을 비교하고, 나아가 환경인자의 영향으로 인한 신체적 변화를 신체조성으로부터 평가 비교하였다. 그리고 성인병의 발병인자의 하나이기도 한 신체내부지방의 축적량을 검사하여 이것과 관계 깊은 영양상태를 평가 하였으며 결과를 요약하면 다음과 같다. 1) 한 $cdot$ 일 양국에서 체위측정치의 차이를 볼 수 있는것은 상지장(上肢長), 경위(頸圍), 상완위(上脘位) 및 전완위(前脘位)로써 한국측이 유의하게 크지만 그 외의 측정치는 본 연구에 참여한 여대생에서는 거의 차이가 없었다. 신장에 대한 체중, 흉위(胸圍), 앉은키(座高)의 비교와 로러지수, BMI,체표면적을 양국간에 대부분 동일하여 유익한 차이는 없었다. 2) 피하지방두께 에서는 협골하연(頰骨下緣),대퇴전부(大腿前部), 후부(後部), 배하부(背下部)를 제외하고는 모두 일본측이 큰 수치를 표시하교 있으나 총 피하지방두께와 평균 피하지방에서는 본 연구에 참여한 여대생에서는 거의 차이가 없었다. 체지방총량에는 본 연구에 ㅏ참여한 여대생 사이에서 2.7kg의 차이가 있으며, 피하지방량에 유의한 차이가 없었을 분 체지방총량 신체내부지방량, 체수분량, 체지방률은 모두 일본측이 유의하게 컸다. 3) 1일의 섭취 에너지 총량에서는 한국측이 유의하게 높고, 3대 영양소의 에너지 비율은 단백질에서는 차이가 없고, 지방 에너지의 비율에서는 일본측이, 당질 에너지의 비율에서는 한국측이 유의하게 높은 수치를 표시하고 있었다. 동물 단백질과 지방질의 섭취량은 반대로 일본이 많았다. 4) 1일 소비 에너지 총량에서는 양국간에 거의 차이가 없었고, 생활 내용별 소비 에너지에서는 睡眠時 座位時 立位時의 소비 에너지에는 유의한 차이를 볼 수 없으나 보행(步行)으로 인한 소비에너지량은 일본측이 다소 높게 나타났다.5) 한국에서는 고추와 마늘의 섭취량이 많고 보통 $3.6pm4.99$g/일, $5.8pm7.53$g/일이며, 일본에서는 거의 섭취하지 않았다.

• KIEAE Journal
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• 제17권4호
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• pp.41-48
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• 2017

Purpose : Currently, 25% of the domestic energy consumption structure is used as building energy, and more than 18% of this energy is consumed in the residential. Accordingly, various efforts and policies that can save energy of the building is being performed. The various researchers are conducting research to diagnose the thermal performance of existing buildings. This study is to apply in the field of precision thermal insulation performance diagnostic method for thermal performance analysis of existing detached house in Seoul, Gangreung, Gyeongju, Pohang. And this paper is analyzed quantitatively measure the existing detached house energy performance. Method: Research methodology analyzed the thermal performance over the Heat Flow Meter method by applying the measurement process and method by applying the criteria of ISO 9869-1 & ASTR method. In this study, the surface heat transfer coefficient was calibrated by applying indoor surface heat transfer resistance with reference to ISO 6946 standard. The measurement error rate between the HFM diagnosis method and the ASTR diagnosis method was reduced and the measurement reliability was obtained through measurement method error verification. Result : As a result of the study, the thermal performance vulnerable parts of the building were quantitatively analyzed, and presented for methods which can be improved capable of efficient energy use buildings.

• 대한한방내과학회지
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• 제45권2호
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• pp.159-166
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• 2024

Objective: The purpose of this case study is to report the effectiveness of the Korean medicine Beewha-eum as a treatment for functional dyspepsia (FD). Methods: A patient diagnosed with a spleen-stomach deficiency-cold pattern in Korean medicine was treated with herbal medicines, including Beewha-eum. Symptom severity was assessed using the degree of self-reported dyspepsia (%), self-reported energy level, amount of food intake (%), total parenteral nutrition rate (cc/hour), body weight (kg), Nepean dyspepsia index (NDI-K), functional dyspepsia-related quality of life questionnaire (FD-QoL), and short form 36-item health survey (SF-36) score. Results: After treatment, the symptom severity of self-reported dyspepsia decreased from 100% to 10 to 15%, and the self-reported energy level increased from 20 to 80. The amount of food intake increased from 5% to 100%, and the total parenteral nutrition rate started from 60 cc/hour end in week 5. Body weight increased from 53.1 kg to 62 kg. The NDI-K score decreased from 105 to 31. The FD-QoL score increased from 19 to 68. The SF-36 score also increased from 102 to 116. Conclusion: The results suggest that the Korean medicine Beewha-eum could be an effective option for treating FD.