• Title/Summary/Keyword: Mass contribution

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Genomics, Proteomics and Nutrition : Applications to Obesity Research

  • Sumithra Urs;Heo, Young-Ran;Kim, Suyeon;Kim, Jung-Han;Brynn H. Jones
    • Nutritional Sciences
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    • v.5 no.3
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    • pp.129-133
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    • 2002
  • Obesity is a major public health problem in western countries. Genetic and environmental factors, separately or in combination are major determinants of fat mass. Both central effectors (primarily hypothalamus) and peripheral tissues (such as adipose tissue) are implicated in the pathogenesis of obesity. A significant number of studies have documented potential contribution of adipose tissue -via its newly discovered secretory function- to the pathogenesis of obesity and co-morbid conditions including cardiovascular disease, diabetes and hypertension. Applications of analytical techniques such as genomics and proteomics have enabled better understanding of biological sciences in general and have only being applied recently to nutritional sciences including obesity research. Here, we review the recent progress in adipose tissue functional genomics and proteomics, and the importance of these studies in energy metabolism and obesity research.

Thrust augmentation through after-burning in scramjet nozzles

  • Candon, Michael J.;Ogawa, Hideaki;Dorrington, Graham E.
    • Advances in aircraft and spacecraft science
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    • v.2 no.2
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    • pp.183-198
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    • 2015
  • Scramjets are a class of hypersonic airbreathing engine that are associated with realizing the technology required for economical, reliable access-to-space and high-speed atmospheric transport. After-burning augments the thrust produced by the scramjet nozzle and creates a more robust nozzle design. This paper presents a numerical study of three parameters and the effect that they have on thrust augmentation. These parameters include the injection pressure, injection angle and streamwise injection position. It is shown that significant levels of thrust augmentation are produced based upon contributions from increased pressure, mass flow and energy in the nozzle. Further understanding of the phenomenon by which thrust augmentation is being produced is provided in the form of a force contribution breakdown, analysis of the nozzle flowfields and finally the analysis of the surface pressure and shear stress distributions acting upon the nozzle wall.

Assessment of the performances of a heat exchanger in a light helicopter

  • Carozza, Antonio
    • Advances in aircraft and spacecraft science
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    • v.2 no.4
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    • pp.469-482
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    • 2015
  • This study has the aim to develop a numerical design regarding the position and the inner performances of a heat exchanger in a light helicopter. the problem was to find first of all the best position of the heat exchanger inside the engine vane in order to maximize the air flow rate capable to pass through the heat exchanger section. It is to be said that the only air contribution in the vane comes from the opening present in the roof under the main rotor. The design has been performed by means of the commercial code Fluent and using the well known grid generator ICEM CFD. Different positions are first investigated so to establish the best one. Subsequently, different areas of the opening on the roof have been considered in order to maximize even more the flow rate in the heat exchanger that was not sufficient based on the first guess of velocity, as aforementioned. At the end interesting design results are presented and discussed by contours of fields and values.

Seismic Capacity Evaluation of the Structures with Vertical Irregularities (수직적 비정형성을 지니는 구조물의 내진성능평가)

  • 홍성걸;김남희;하태휴
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2001.09a
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    • pp.208-215
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    • 2001
  • The vertical irregularities occurred in the structure may lessen the overall seismic capacity of the structure. Seismic capacity evaluation guidelines (e.g. FEMA 175, ATC-14) propose the criterion for the vertical irregularities of mass, stiffness and strength respectively. But, the criterion seems groundless and leads us to make a true/false decision only. This study is to draw a reasonable basis on which multi-level grading is possible based fur the evaluation of existing buildings. Time history analysis for 3-,5-, and 10-story steel frame structures has been performed using several earthquake data. ANN (Artificial Neural Network) is introduced to find the relative contribution factor of the irregularities along the irregular position. Also, the application system fur the seismic capacity evaluation can be established using the trained ANN.

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Sound-Insulation Performance of Aluminum Extruded Panel by Charging Foam in a High-speed Train (고속철도차량용 알루미늄 압출재의 차음성능에 대한 폼 충전효과)

  • Lee, Joong-Hyeok;Park, In-Seok;Kim, Seock-Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2012.04a
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    • pp.582-585
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    • 2012
  • The aluminum extruded panel used for a high speed train shows the largest contribution to sound insulation performance of the train body. However, comparing with the flat panel having the same weight, the transmission loss falls sharply in the local resonance frequency band. Such fall of transmission loss can be improved by increasing the damping of local resonance. This study examines the charging effect of an urethane foam on the aluminum extruded panel of a high speed train. We charged the urethane foam with different mass density and in different way in the core part of the extruded panel. We measure the transmission loss and compare the sound insulation performance according to the density and charging method. Finally, Improvement effect of the transmission loss is compared and analysed in aspect of weight increment.

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Contribution and Future Direction in the Study of Aquacultural Oceanography in Jinhae Bay, Korea (진해만의 양식해양학적 연구의 업적과 미내의 과제)

  • CHO Chang-Hwan
    • Journal of Aquaculture
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    • v.4 no.2
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    • pp.129-136
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    • 1991
  • This is a review of the studies on aquaculture and its environments in Jinhae Bay, one of the most productive areas in the south coastal waters in Korea, carried out since 1960's. It's content consists of describing the outlines of, (1) a brief history of shellfish culture development and the study of oceanic environments relating to the aquaculture, (2) the oceanographic studies on the eutrophication, red tides, and the mass mortality of shellfish due to pollution and (3) the studies on forecasting aquaculture and oceanographic conditions, and on the direction of aquacultural oceanographic studies in the near future.

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Effect of curing temperature and blast furnace slag concrete on concrete strength development (양생온도가 고로슬래그 콘크리트의 강도발현에 미치는 영향분석)

  • Lee, Kyu-Dong;Jun, Myeong-Il;Lee, Chang-Soo;Kim, Dong-Sik
    • Journal of the Society of Disaster Information
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    • v.2 no.1
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    • pp.129-137
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    • 2006
  • The present work is attempt to evaluate the temperature dependence of blast furnace slag concrete(BFSC) based on the concrete strength cured with different curing temperatures and ages. A equivalent substitution index(ESI) was induced to explain temperature dependence of concrete quantitatively as well as concrete strength. The results from compressive strength showed substantial crossover effect. which is the phenomenon that the compressive strength cured at low temperature becomes stronger than the one cured at high temperature. The crossover effect found more definitely on BFSC than plain concrete.. The ESI became 1.1 and 1.0 for the BFSC cured at $20^{\circ}C$ and $30^{\circ}C$ after age of 56 days, respectively. Which means that the contribution to strength development of blast furnace slag per unit mass is stronger than that of the Portland cement. It was considered therefore that the optimum curing temperature for BFSC is $20^{\circ}C$.

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Sound Insulation Performance of the Side Layered Panels in the Next Generation High Speed Train (차세대 고속철도 차량 측면 적층재의 차음성능)

  • Lee, Joong-Hyeok;Lee, Ho-Jin;Park, In-Seok;Kim, Seock-Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2011.10a
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    • pp.457-462
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    • 2011
  • The sidewall of the HEMU-400x consists of two parts. One is the multi-layered structure including aluminium extruded panel and the other is the double glazed window. When the train runs in a tunnel, the equivalent sound insulation performance of the side wall significantly influences the internal noise levels. In aspect of the sound insulation strategy, it is important to make two parts have similar performance. In this study, the intensity sound transmission loss (ITL) is measured on the specimens of the two parts. Mass law deviation (MLD) is considered in order to compare the sound insulation performance of the two parts in respect of the weight. Contribution of each part to the sound insulation is analyzed and the sound insulation strategy is investigated to reduce the interior noise.

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Computer Simulation of Powertrain Forced Torsional Vibration (차량주행시 동력전달계의 강제진동 해석)

  • 최은오;안병민;홍동표
    • Journal of KSNVE
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    • v.7 no.5
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    • pp.853-860
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    • 1997
  • For this study, the multi-degree of freedom analysis model of torsional vibration was developed. This model is combined with mass moment of inertia and torsional spring in two wheel drive and four wheel drive vehicle. We compared and analyzed torsional vibration characteristics by natural frequencies and mode shapes which are obtained by free vibration analysis of this model. And we studied torsional vibration contribution of driveline elements by performing the forced vibration analysis of engine excitation torque. The validity of this model is demonstrated by the field test. The reduction effect of the torsional vibration along the driveline design factor is presented by the analytical results.

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The evaluation of vibration contribution about the eccentric rotor system by multiple dimensional spectral analysis (다차원 해석법을 이용한 편심 회전체의 전달 기여도 평가)

  • 조문갑;조용구;김동원;이정윤;오재응
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.11a
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    • pp.298-303
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    • 2003
  • The eccentric rotor system has various problems by vibration of unbalance mass. Specially, it is difficult to analyze vibration problem for the drum washing machine due to correlation of transmission paths. We analyze the mechanical structure by multidimensional spectral density to identify the maximum vibration magnitude at the frequency domain. It estimates the coherence function of the signals to pass the transmission paths. In case of the drum washing machine, because the transmission paths are correlated partially it needs to determinate the priority ranking. And the correlated parts are eliminated using conditioned spectral density function. Finally the shielding effect method confirms the reasonability of the modeling.

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