• Title/Summary/Keyword: Flow gain

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Design of a Low Power Capacitor Cross-Coupled Common-Gate Low Noise Amplifier (캐패시터 크로스 커플링 방법을 이용한 5.2 GHz 대역에서의 저전력 저잡음 증폭기 설계)

  • Shim, Jae-Min;Jeong, Ji-Chai
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.23 no.3
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    • pp.361-366
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    • 2012
  • This paper proposes a low power capacitor cross-coupled 5.2 GHz band low noise amplifier(LNA) using the current-reused topology with the TSMC 0.18 ${\mu}m$ CMOS process. The proposed 5.2 GHz band LNA uses a capacitor cross-coupled $g_m$-boosting method for reducing current flow of circuit and a current-reused topology to decrease total power dissipation. The parallel LC networks are used to reduce size of spiral inductors. The simulation results show high gain of 17.4 dB and noise figure(NF) of 2.7 dB for 5.2 GHz.

Numerical Analysis of Integrated Fuel Processing System Considering Thermo-Chemical Energy Balance (열/화학적 에너지 평형을 고려한 통합 연료 개질 시스템의 수치적 연구)

  • Noh, Junghun;Jung, Hye-Mi;Jung, Un-Ho;Yoon, Wang-Lai;Um, Sukkee
    • 한국신재생에너지학회:학술대회논문집
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    • 2010.11a
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    • pp.111.1-111.1
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    • 2010
  • This paper focuses on a systematic configuration of steam reforming fuel processor, particularly designed for small and medium sized hydrogen production application. In a typical integration of the fuel processor, there exist significant temperature gradients over the entire system which has negative effect on both catalyst life-time and system performance. Also, the volumetric inefficiency should be avoided to obtain the possible compactness for the commercial purpose. In the present work, the computational analysis will be performed to gain the fundamental insight on the transport phenomena and chemical reactions in the reformer consisting of preheating, steam reforming (SR), and water gas shift (WGS) reaction beds in the flow direction. Also, the fuel processing system includes a top-fired burner providing necessary thermal energy for endothermic catalytic reactor. A fully two-dimensional numerical modeling for a integrated fuel processing system is introduced for in-depth analysis of the heat and mass transport phenomena based on surface kinetics and catalytic process. In the model, water gas shift reaction and decomposition reaction were assumed to be at equilibrium. A kinetic model was developed and then computational results were compared with the experimental data available in the literature. Finally, the case study was done by considering the key parameters, i.e. steam to carbon (S/C) ratio and temperature. The computer-aided models developed in this study can be greatly utilized for the design of advanced fast-paced compact fuel processors research.

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Impacts of Golden Stock on Corporations (황금주가 회사에 미치는 영향)

  • Park, Jong-Ryeol
    • The Journal of the Korea Contents Association
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    • v.9 no.12
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    • pp.253-260
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    • 2009
  • Gold stock could include the U.K. in the European economy by the alternative plan of the problems that it was occurred while nationalizing industry and a company for economic recovery and national profit after the World War Ⅱ and it was wide and came to open in the country of European most. However, the negation was sentenced to it for the reason of the gold stock which the U.K. adopted in European many countries infringing "freedom of the capital movement" at a European court of law. However, I consider gold stock positively to protect it from hostile M&A of the company of the national strategy from the Middle East and an Asian national rich fund recently in France and Germany. If our country looks straight at reality, Urstatut or the agreement of the majority stockholder have a very strict matter assuming the protection of the existing shareholder and must be able to gain the favor if you look by the flow of such world economy.

Impact of the Geochemical Characteristics and Potential Contaminants Source of Surrounding Soil on Contamination of a Reservoir in an Island (II) - Appraisal of flow categorized by Incursion Using Rainfall-Runoff Model - (주변토양의 지구화학적 특성과 잠재적 오염원이 도서지역 저수지의 오염부하에 미치는 영향(II) - 강우 유출 모형을 이용한 유입경로별 유출량 평가 -)

  • Park, Sun-Hwan;Park, Wan-Sub;Jun, Young-Bong;Kim, Chang-Gyun;Kim, Sung-Gou;Kang, Seon-Hong;Chang, Yoon-Young;Jeong, Jeong-Ho;Jung, Jong-Ahm
    • Journal of Environmental Impact Assessment
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    • v.19 no.3
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    • pp.215-222
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    • 2010
  • This research aims to gain the result of assessment of inflow categorized by runoff path using DIROM (Daily Irrigation Reservoir Operation Model) for Baengnyeong-myeon reservior which was built for residents of Baengnyeong island to solve the shortage of drinking water and stable supply of domestic water. The simulation results of DIROM and actual hydrograph of the reservoir show very low correlation with geological characteristics. The simulation results by DIROM after adjusting with modified Tank III model which considers all outflow from Tank II model as interflow among 3 level tanks show good correlation of its regional runoff and inflow characteristics with $R^2$=0.9058. In the study area, diffluence of 37% of rain fall of the study year has been simulated, which shows low result compared to the average river runoff of national water resource. In addition, 34.5% of total inflow to the study reservoir is mainly interflow and baseflow among expected several channels.

Modeling and validation of a parabolic solar collector with a heat pipe absorber

  • Ismail, Kamal A.R.;Zanardi, Mauricio A.;Lino, Fatima A.M.
    • Advances in Energy Research
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    • v.4 no.4
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    • pp.299-323
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    • 2016
  • Cylindrical parabolic solar concentrators of small concentration ratio are attractive options for working temperatures around $120^{\circ}C$. The heat gained can be utilized in many applications such as air conditioning, space heating, heating water and many others. These collectors can be easily manufactured and do not need to track the sun continuously. Using a heat pipe as a solar absorber makes the system more compact and easy to install. This study is devoted to modeling a system of cylindrical parabolic solar concentrators of small concentration ratio (around 5) fitted with a heat pipe absorber with a porous wick. The heat pipe is surrounded by evacuated glass tube to reduce thermal losses from the heat pipe. The liquid and vapor flow equations, energy equation, the internal and external boundary conditions were taken into consideration. The system of equations was solved and the numerical results were validated against available experimental and numerical results. The validated heat pipe model was inserted in an evacuated transparent glass tube as the absorber of the cylindrical parabolic collector. A calculation procedure was developed for the system, a computer program was developed and tested and numerical simulations were realized for the whole system. An experimental solar collector of small concentration, fitted with evacuated tube heat pipe absorber was constructed and instrumented. Experiments were realized with the concentrator axis along the E-W direction. Results of the instantaneous efficiency and heat gain were compared with numerical simulations realized under the same conditions and reasonably good agreement was found.

Compensatory Growth of Grower Olive Flounder (Paralichthys olivaceus) with Different Feeding Regime at Suboptimal Temperature

  • Cho, S.H.;Kim, K.T.;Choi, I.C.;Jeon, G.H.;Kim, D.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.2
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    • pp.272-277
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    • 2012
  • Compensatory growth of grower olive flounder (Paralichthys olivaceus) was determined at suboptimal temperature ($13.0{\pm}1.9^{\circ}C$). Fifteen fish averaging 201.1 g per tank were distributed into 18 of 300 L flow-through tanks. Six treatments were prepared in triplicate: fish were hand-fed with an extruded pellet to apparent satiation once a day for 16 weeks (16 WF); and the other five groups of fish were hand-fed for 15, 14, 13, 12 and 10 weeks after 1-, 2-, 3-, 4- and 6-week feed deprivation, referred to as 15 WF, 14 WF, 13 WF, 12 WF and 10 WF, respectively. A linear relationship between body weight of fish and feed deprivation was observed: Y (Body weight of fish) = -1.81X (Weeks of feed deprivation)+201.07, $R^2$ = 0.83. Weight gain of grower olive flounder in 15 WF, 14 WF, 13 WF and 12 WF treatments was comparable to that of fish in 16 WF treatment, but lower than that of fish in 10 WF treatment. Specific growth rate of fish in 15 WF treatment was higher than that of fish in 16 WF, 14 WF and 10 WF treatments. Feed consumption of fish was not affected by feeding regime. Feed and protein efficiency ratios of fish in 15 WF treatment were higher than those of fish in 13 WF, 12 WF and 10 WF treatments. Grower olive flounder could achieve full compensatory growth when fish were daily fed for 12 weeks after 4-week feed deprivation at suboptimal temperature.

A Preventive Intra-Path Load Balancing Based on the Probabilistic Characteristics of the Quality-of-service (서비스 품질의 확률적 특성에 기초한 예방적 경로 부하 밸런싱)

  • Kim, Tae-Joon;Suh, Bong-Sue
    • Journal of Korea Multimedia Society
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    • v.13 no.2
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    • pp.279-286
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    • 2010
  • Unbalanced traffic load offered to the nodes making up a path in the network guaranteeing quality-of-service has been known as a main cause deteriorating the capability of the path in admitting traffic flows. Several path load balancing methods have been developed to resolve this problem which used a feedback control scheme that adjusts the delay budget of a flow allocated to each node according to the conditions of available resource in the path. Because of no consideration about the probabilistic characteristics of the service quality, it is impossible for them to prevent in advance a bottleneck on the path which leads to a native restriction in the improvement of the capability being deteriorated. This paper proposes a preventive intra-path load balancing method applicable to the RSVP system which is based on the probabilistic characteristics of the quality-of-service of the offered load. The results of the simulation of the proposed method on a simple evaluation network showed that it provides the gain of 4~22% compared to the legacy one in terms of the number of admitted flows.

Effects of Tong Xin Lou (TXL) on levels of serum lipid in high fat diet-induced dyslipidemia in mice (통심락(通心絡)이 고지방식이로 유도된 이상지질혈증 생쥐의 체내 지질 변화에 미치는 영향)

  • Ha, Tae-Hoon;Kim, Hyun-Young;Kim, Hyung-Woo;Cho, Su-In;Kim, Young-Gyun
    • The Korea Journal of Herbology
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    • v.27 no.3
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    • pp.107-112
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    • 2012
  • Objectives : This study was designed to investigate the effects of Tong Xin Lou (TXL) on lipid accumulation in liver tissue in Hypercholesterolemic mice. TXL is new drug, which is one of Cardiotonic Pills. TXL is used for activating the blood flow in the restoration stage of cerebral infarction, and for alleviation of angina pectoris including the symptoms as chest oppressed and stabbing pain. Methods : Hyperlipidemia was induced by providing high fat diet for 6 weeks. Normal group was provided with normal rodent diet. TXL was administered orally in the concentration of 10 mg/day for 2 weeks (TXL group). D/W was administered orally in CTL group for 2 weeks. We observed histopathological changes in liver and heart tissues, and also investigated the effect on body weights, and levels of total cholesterol, HDL-cholesterol, LDL-cholesterol and triglyceride in serum. Results : In this study, TXL did not affects weight gain in hypercholesterolemic mice. TXL group showed downward tendency of lipid accumulation compared with CTL group. In addition, oral administration of TXL lowered levels of total cholesterol (P < 0.05) and triglyceride (P < 0.05), which were elevated by induction of hypercholesterolemia. Conclusion : These results suggest that TXL can prevent lipid accumulation in liver tissue through regulation of dyslipidemia.

Effects of the Dietary Inclusion of Porphyra and Sea Tangle Laminaria japonica on the Growth, Feed Utilization, Body Composition, and Plasma Chemistry of Juvenile Korean Rockfish Sebastes schlegeli (사료내 김(Porphyra)과 다시마(Laminaria japonica) 첨가가 조피볼락(Sebastes schlegeli) 치어의 성장, 사료 이용성, 체조성 및 혈액 성상에 미치는 영향)

  • Jeon, Gyu Ho;Cho, Sung Hwoan;Lee, Sang Min;Nam, Taek Jeong;Kim, Dong Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.5
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    • pp.546-551
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    • 2013
  • This study examined the effects of the dietary inclusion of Porphyra and sea tangle Laminaria japonica on the growth, feed utilization, body composition, and plasma chemistry of juvenile Korean rockfish Sebastes schlegeli. Eight hundred and forty juvenile fish averaging 5.0 g were allocated 40 fish per tank to 21 180-L flow-through tanks. Seven experimental diets were prepared: control (Con) without additive, 0.5 and 1% Porphyra extract (PE), 3% Porphyra powder (PP), 0.5 and 1% sea tangle extract (STE) and 3% sea tangle powder (STP), referred to as PE-0.5, PE-1, PP-3, STE-0.5, STE-1, and STP-3, respectively. Each additive was included in the experimental diet at the expense of the same amount of wheat flour. Each experimental diet was fed to triplicate groups of fish. The experimental diets had no effect on the survival, weight gain or specific growth rate of the fish, feed consumption, feed efficiency ratio, protein efficiency ratio, protein retention, hepatosomatic index, condition factor, moisture or crude protein content of the entire body excluding the liver or moisture, crude protein or crude lipid content of the liver. None of the plasma parameters were affected by the experimental diets. Based on these results, the dietary inclusion of Porphyra and sea tangle did not affect the growth, feed utilization, body composition or plasma chemistry of juvenile Korean rockfish.

Exogenous Morphine Inhibits Human Gastric Cancer MGC-803 Cell Growth by Cell Cycle Arrest and Apoptosis Induction

  • Qin, Yi;Chen, Jing;Li, Li;Liao, Chun-Jie;Liang, Yu-Bing;Guan, En-Jian;Xie, Yu-Bo
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.4
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    • pp.1377-1382
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    • 2012
  • Morphine is not only an analgesic treating pain for patients with cancer but also a potential anticancer drug inhibiting tumor growth and proliferation. To gain better insight into the involvement of morphine in the biological characteristics of gastric cancer, we investigated effects on progression of gastric carcinoma cells and the expression of some apoptosis-related genes including caspase-9, caspase-3, survivin and NF-${\kappa}B$ using the MGC-803 human gastric cancer cell line. The viability of cells was assessed by MTT assay, proliferation by colony formation assay, cell cycle progression and apoptosis by flow cytometry and ultrastructural alteration by transmission electron microscopy. The influences of morphine on caspase-9, caspase-3, survivin and NF-${\kappa}B$ were evaluated by semi-quantitative RT-PCR and Western blot. Our data showed that morphine could significantly inhibit cell growth and proliferation and cause cell cycle arrest in the G2/M phase. MGC-803 cells which were incubated with morphine also had a higher apoptotic rate than control cells. Morphine also led to morphological changes of gastric cancer cells. The mechanism of morphine inhibiting gastric cancer progression in vitro might be associated with activation of caspase-9 and caspase-3 and inhibition of survivin and NF-${\kappa}B$.