• 제목/요약/키워드: Lowering

검색결과 3,059건 처리시간 0.026초

파랑 중 해상 크레인의 하강 작업 수치 시뮬레이션 (Lowering Simulation using Floating Crane in Waves)

  • 남보우;홍사영;김병완;이동엽
    • 한국해양공학회지
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    • 제26권1호
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    • pp.17-26
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    • 2012
  • A coupled analysis of a floating crane barge with a crane wire and hanging structure is carried out in thetime domain. The motion analysis of the crane barge is based on the floating multi-body dynamics, and thecrane wire is modeled as a simple spring tension. The hanging structure is assumed to be a rigid body with 3 degree-of-freedom translational motion. In this study, numerical simulations were conducted at three different stages. First, the developed code was validated by comparing the time-domain motion response of a crane barge with the frequency-domain results. Then, a coupled analysis of a crane barge and simple structure hanging by the crane wire was performed using the present scheme. The motion response and wire tension from the present calculations are compared with the results of OrcaFlex. The agreement between the two sets of results isfairly good. Last, lowering simulations in regular and irregular waves were conducted considering buoyancy changes in the hanging structure. The effects of the wave conditions, structure's weight, wire length, and lowering speed on the wire tension are considered.

A New Two-Dimensional Model for the Drain-Induced Barrier Lowering of Fully Depleted Short-Channel SOI-MESFET's

  • Jit, S.;Pandey, Prashant;Pal, B.B.
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제3권4호
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    • pp.217-222
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    • 2003
  • A new two-dimensional analytical model for the potential distribution and drain-induced barrier lowering (DIBL) effect of fully depleted short-channel Silicon-on-insulator (SOI)-MESFET's has been presented in this paper. The two dimensional potential distribution functions in the active layer of the device is approximated as a simple parabolic function and the two-dimensional Poisson's equation has been solved with suitable boundary conditions to obtain the bottom potential at the Si/oxide layer interface. It is observed that for the SOI-MESFET's, as the gate-length is decreased below a certain limit, the bottom potential is increased and thus the channel barrier between the drain and source is reduced. The similar effect may also be observed by increasing the drain-source voltage if the device is operated in the near threshold or sub-threshold region. This is an electrostatic effect known as the drain-induced barrier lowering (DIBL) in the short-gate SOI-MESFET's. The model has been verified by comparing the results with that of the simulated one obtained by solving the 2-D Poisson's equation numerically by using the pde toolbox of the widely used software MATLAB.

Threshold Voltage Modeling of Double-Gate MOSFETs by Considering Barrier Lowering

  • Choi, Byung-Kil;Park, Ki-Heung;Han, Kyoung-Rok;Kim, Young-Min;Lee, Jong-Ho
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제7권2호
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    • pp.76-81
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    • 2007
  • Threshold voltage ($V_{th}$) modeling of doublegate (DG) MOSFETs was performed, for the first time, by considering barrier lowering in the short channel devices. As the gate length of DG MOSFETs scales down, the overlapped charge-sharing length ($x_h$) in the channel which is related to the barrier lowering becomes very important. A fitting parameter ${\delta}_w$ was introduced semi-empirically with the fin body width and body doping concentration for higher accuracy. The $V_{th}$ model predicted well the $V_{th}$ behavior with fin body thickness, body doping concentration, and gate length. Our compact model makes an accurate $V_{th}$ prediction of DG devices with the gate length up to 20-nm.

지질대사(脂質代謝)에 관여하는 인자(因子) (Some Factors Affecting Lipid Metabolism)

  • 남현근
    • 한국식품영양과학회지
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    • 제15권2호
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    • pp.191-200
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    • 1986
  • It is now generally accepted that individuals at increased risk for cardiovascular disease may be identified by certain traits or habbits. The factors such as high blood pressure, elevated blood cholestrol, age, sex and obesity are associated with increseaed frequency of disease. The blood cholesterol level lowering will decrease cardiovascular disease risk. The regression of atherosclerosis can be achieved by lowering the level of circulating cholesterol. Those things are connected with the quantity and quality of protein, fats, carbohydrates, especially soluble and non-soluble fiber, magnesium and calcium. The lipoprotein and lipid metabolism are connected with the lipid transport. The factors on lipid absorption and blood serum lipid pattern of human are exist. The factors have a variety of materials with different chemical and physical properties. The soluble fiber diet make a low blood and liver lipids. Many kind of soluble fiber results in a lowering of blood cholesterol and triglyceride levels. The cholesterol lowering effects of dietery fiber may be a results of alterations of in intestinal handling of fats, hepatic metabolism of fatty acid or triglyceride acid metabolism of lipoprotein. It is investigated that the high density lipoprotein (HDL) is inversely related to coronary artery disease. It has been postulated that HDL may be an important factor in cholesterol efflux from the tissues, therby reducing the amount of cholesterol deposited there. Alternatively, the HDL may pick up cholestyl ester and phospholipid during normal VLDL lipolysis in the plasma. The HDL levels are relatively insensitive to diet. At present time, the cause-and -diet effect of HDL's inverse relation to CHD remains unclear.

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Combined Lowering Effects of Rosuvastatin and L. acidophilus on Cholesterol Levels in Rat

  • Wang, Lijun;Zhou, Baihua;Zhou, Xue;Wang, Yang;Wang, Hongwei;Jia, Shengying;Zhang, Zhipeng;Chu, Chao;Mu, Jianjun
    • Journal of Microbiology and Biotechnology
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    • 제29권3호
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    • pp.473-481
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    • 2019
  • Statins are a class of lipid-lowering drugs commonly used in the prevention of cardiovascular diseases. However, statin therapy presents many limitations, which have led to an increased interest in non-drug therapies, such as probiotics, to improve blood cholesterol levels. Indeed, probiotic strains such as Lactobacillus acidophilus have been found to improve blood lipid profiles, especially in reducing total cholesterol and LDL-C levels. In this study, we established a high-cholesterol rat model and studied the effect of Lactobacillus acidophilus administration alone or in combination with rosuvastatin. We were able to show that Lactobacillus exerts a cholesterol-lowering effect. Additionally, we observed that when administered together, rosuvastin and Lactobacillus exert a combined cholesterol-lowering effect. Altogether, our data advocate for the possibility of establishing probiotics as non-drug supplements for the treatment of hypercholesterolemia.

Experimental study on effect of underground excavation distance on the behavior of retaining wall

  • Lee, Seok-Won
    • Geomechanics and Engineering
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    • 제17권5호
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    • pp.413-420
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    • 2019
  • The changes in earth pressure and ground settlement due to underground excavation near an existing retaining wall were studied experimentally according to the separation distance between the underground excavation and the retaining wall. In addition, this study attempted to experimentally prove that the arching phenomenon occurred during the construction of the underground space. A model tank having 120 cm in length, 160 cm in height, and 40 cm in width was manufactured to simulate underground excavation through the use of five separated base wall bodies. The variation of earth pressure on the retaining wall was measured according to the underground excavation phase through the use of 10 separated right wall bodies. The results showed that the earth pressure on the retaining wall was changed by the lowering of the first base bottom wall; however, the earth pressure was not changed significantly by the lowering of the third base bottom wall, since the third base wall had sufficient separation distance from the retaining wall. Lowering of the first base wall induced a decrease in the earth pressure in the lower part of the retaining wall; in contrast, lowering of the first base wall induced an increase in the earth pressure in the middle part of the retaining wall, proving the arching effect experimentally. It is necessary to consider the changes in earth pressure on the retaining wall in designing earth retaining structures for sections where the arching effect occurs.

Enhanced Cholesterol-Lowering and Antioxidant Activities of Soymilk by Fermentation with Lactiplantibacillus plantarum KML06

  • Ji Seung Han;Jae Yeon Joung;Hyung Wook Kim;Jin Hwan Kim;Hyo Su Choi;Hyun Jin Bae;Ji Hun Jang;Nam Su Oh
    • Journal of Microbiology and Biotechnology
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    • 제33권11호
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    • pp.1475-1483
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    • 2023
  • This study aimed to evaluate the cholesterol-lowering and antioxidant activities of soymilk fermented with probiotic Lactobacillaceae strains and to investigate the production of related bioactive compounds. Lactiplantibacillus plantarum KML06 (KML06) was selected for the fermentation of soymilk because it has the highest antioxidant, cholesterol-lowering, and β-glucosidase activities among the 10 Lactobacillaceae strains isolated from kimchi. The genomic information of strain KML06 was analyzed. Moreover, soymilk fermented with KML06 was evaluated for growth kinetics, metabolism, and functional characteristics during the fermentation period. The number of viable cells, which was similar to the results of radical scavenging activities and cholesterol assimilation, as well as the amount of soy isoflavone aglycones, daidzein, and genistein, was the highest at 12 h of fermentation. These results indicate that soymilk fermented with KML06 can prevent oxidative stress and cholesterol-related problems through the production of soy isoflavone aglycones.

녹지의 배치와 식재형태가 열환경저감효과에 미치는 영향 (Temperature Lowering Effects Varied by the Arrangement and Types of Vegetation)

  • 윤용한
    • 아시안잔디학회지
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    • 제17권4호
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    • pp.165-172
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    • 2003
  • 본 연구는 녹지의 배치와 식재형태가 기온저감효과에 미치는 영향을 파악한 결과 다음과 같은 점이 밝혀졌다. 1) 녹지의 기온분포도로부터 고온역은 주변시 가지에서, 저온역은 각 녹지내의 식재지주변과 소하천주변에서 확인되었다. 2) 녹지의 배치와 기온과의 관계를 보면, 저온역은 각 녹지와 거의 일치하고 녹지간 시가지 및 풍하쪽에도 저온역이 형성되었다. 3) 녹지간 시가지와 기온과의 관계를 보면 저온역은 풍하쪽 시가지뿐 아니라 녹지간 시가지에서도 나타났다. 또한, 풍상쪽에 녹지가 존재하지 않은 경우에도 녹지간 시가지는 주변 시가지 보다 낮은 기온이었다. 4) 토지피복비율과 기온에서 식재지, 초지 및 수면이 증가하면 모두 기온저감에 효과적이고, 나지의 증가는 기온상승에 효과적이다. 5) 교목, 소교목의 순으로 그 그루의 증가는 기온저감에 유효하게 관련되어 있는 것이 파악되었다.

고혈압(高血壓)에 강심산(强心散)과 Hydralazine, Clonidine, Hydrochlorothiazide 및 Furosemide의 병용투여(倂用投與)에 관한 실험적(實驗的) 연구(硏究) (Experimental Studies on the interaction of Kangsimsan and Hydralazine, Verapamil, Clonidine, Hydrochlorothiazide and Furosemide)

  • 김진돈;조기호;김영석;배형섭;이경섭
    • 대한한의학회지
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    • 제15권2호
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    • pp.198-211
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    • 1994
  • After giuing some anti-high blood pressure medicine of boiled-compressed fluid and 5-Kinds factors(Hydralazine, Verapamil, Clonidine, Furosemide and Hydrochlorothiazide with Kangsimsan to animals in single or together. I got the following conclusion in comparing blood-pressure and pulse of circulating system with urinating operation. 1. By joint-use of Kangsimsan and Hydralazine. it was found out that the effect of blood-pressure lowering continues longer in together-use than in single. And I coule see that the number of pulse increased. 2. By joint-use of Kangsimsan and Verapamil. the blood-pressure lowering operation was kept better in together-use than in single. the number of pulse was not affected any. 3. By joint-use of Kangsimsan and Clonidine the blood-pressure lowering operation was not found out any concrete result. 4. By joint-use of Kangsimsan and Furosemide. the Remarkble effect of Urinization was recognized to be much better in joint-use than in single. 5. By joint-use of Kangsimsan and Hydrochlorothiazide. the suppressing effect of urinization was recognized to be much better in joint-use than in single. Therefore in consideration of the above study and observation. when the joint-use of Kangsimsan and the blood-pressure lowering medicine. Hydralazine and Verapamil. the period of blood-pressure lowering was kept and I can conclude that in case of joint-use of Furosemide, a kind of good urinization. the effect of urinization by Furosemide is increased, but that of Hydrochlorothiazide is disturbed.

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흰쥐에서 Ketamine에 의한 혈압하강 (Ketamine-Induced Blood Pressure Lowering in the Rat)

  • 유선봉;김상진;이문영;강형섭;김진상
    • 한국임상수의학회지
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    • 제22권3호
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    • pp.220-227
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    • 2005
  • Although ketamine has been used in the field of anesthetic medicine for its safety and favourable respiratory effects, the cardiovascular effects of ketamine is still controversial. To clarify the action and mechanism of ketamine upon cardiovascular system, arterial blood pressure, tension of aortic ring, left ventricular developed pressure and heart rate were measured in rats, Ketamine produced two types of effects on arterial blood pressure in anesthetized rats; monophasic effect (blood pressure lowering) and biphasic effect (initial transient blood pressure increasing following sustained lowering), The ketamine-induced lowering of aterial blood pressure showed a concentration-dependent manner, inhibited by the pretreament of $MgCl_2$ and potentiated by the pretreatment of $CaCl_2$. The ketamine-induced lowering of aterial blood pressure was suppressed by the pretreatment of nifedipine, verapamil or lidocaine. In phenylephrine-precontracted endothelium intact (+E) aortic rings, ketamine sometimes caused a small enhancement of contraction ($112.5{\pm}3.6{\%}$). However, in many experiments, ketamine produced a concentration-dependent relaxation in +E aortic rings precontracted with either phenylephrine or KCl. Ketamine-induced relaxation was significantly greater in KCl-precontracted strips than phenylephrine-precontracted strips. In phenylephrine-precontracted +E aortic rings, the ketamine-induced vasorelaxation was not suppressed by endothelium removal or by the pretreatment of a nitric oxide synthase inhibitors, L-$N^G$-nitro-arginine and a guanylate cyclase inhibitors, methylene blue, suggesting that the ketamine-induced vasorelaxation is not dependent on the endothelial function. In addition, ketamine elicited an increase in left ventricular developed pressure in perfused hearts accompanied by decrease in heart rate. These results suggest that ketamine could evoke a hypotension due to vasorelaxation and decrease in heart rate in rats. The inhibitory effect of cardiovascular system might be associated with modulation of $Ca^{2+}$ homeostasis.