• 한국시뮬레이션학회논문지
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• 제9권4호
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• pp.51-58
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• 2000

The control of the data retention time is a main issue for realizing future high density dynamic random access memory. The novel junction process scheme in sub-micron DRAM cell with STI(Shallow Trench Isolation) has been investigated to improve the tail component in the retention time distribution which is of great importance in DRAM characteristics. In this' paper, we propose the new implantation scheme by gate-related ion beam shadowing effect and buffer-enhanced ${\Delta}Rp$ (projected standard deviation) increase using buffered N-implantation with tilt and 4X(4 times)-rotation that is designed on the basis of the local-field-enhancement model of the tail component. We report an excellent tail improvement of the retention time distribution attributed to the reduction of electric field across the cell junction due to the redistribution of N-concentration which is Intentionally caused by ion Beam Shadowing and Buffering Effect using tilt implantation with 4X-rotation. And also, we suggest the least requirements for adoption of this new implantation scheme and the method to optimize the key parameters such as tilt angle, rotation number, Rp compensation and Nd/Na ratio. We used MEDICI Simulator to confirm the junction device characteristics. And measured the refresh time using the ADVAN Probe tester.

• 한국철도학회논문집
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• 제7권3호
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• pp.259-263
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• 2004

The running safety of a railway vehicle depends on the design parameters and contact condition between wheel and rail. In this study, the effect of the conicity of wheel tread is analyzed using ADAMS/RAIL software on running situation. Modal analysis shows in 0.6 Hz natural frequency of lateral mode in fully arranged the KTX cars. The excessive vibration of the tail cars occurs in the 17th car as the speed and the stiffness of the secondary suspension increases, and especially for 1/40 conicity of the GV40 wheel. Also, the analysis shows that combination of wheel profile, GV40 for power cars and XP55 for passenger cars can reduce the lateral vibration of the tail cars.

• 한국항공우주학회지
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• 제33권5호
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• pp.9-17
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• 2005

헬리콥터 초기 설계 단계에서는 형상 변화에 따른 공력 성능 변화를 예측하여 최적의 형상을 결정한다. 덮개꼬리로터에서는 공력성능 개선을 위해 블레이드와 덮개사이의 끝단간극, 블레이드 평면형, 그리고 블레이드 배치의 최적화가 필요하다. 본 연구에서는 비정렬 격자에 기초한 비점성 압축성 로터 유동 해석 코드를 이용하여 설계 초기 기본형상의 덮개꼬리로터에 대해 끝단간극, 블레이드 평면형, 그리고 블레이드 배치 등의 형상변화에 따른 공력 성능을 예측하고 그 특성을 파악하였다.

• 한국식품영양학회지
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• 제3권1호
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• pp.39-56
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• 1990

The effects of six kinds of phosphate complex on the water holding capacity (W.H.C) and protein solubility of hair tail, yellow tail runner and dried pollack meat paste were investigated and animal meat(pork, chicken and hare meat complex) The formulation of six kind of phosphate complex employed to this experiment were made by mixing several phosphate such as sodium polyphosphate, sodium pyrophosphate, sodium acid pyrophosphate, potassim pyrophosphate, sodium ultra-meta-phosphate, sodium-tetra-phosphate and monoglyceride at different mixture ratio Among the six kinds of phosphate complex, phosphate B complex which was formulated by mixing sodium polyphosphate 40%, sodium pyrophosphate 30%, sodium tetra mata phosphate 10%, sodium ultra meta phosphate 10% was most effective on enchanging the W H. C, and protein solubility of hair tail, yellow tail runner dried pollack meat past and in case of pork, chicken and hare meat paste. Phosphate C complex which was formulated by mixing sodium polyphosphate 50%. sodium pyrophosphate 30%, sodium tetra meta phosphate 10%, potassium pyrophosphate 10%, was more effective them other phosphate complex, and thief optimum addition level was 0.5% respectively in weight of fish meat paste. Texture characteristics such as hardness, cohesiveness and springiness value of Kamaboko(fish meat and pork, chicken, hare meat complex past meat product) were evaluted as best when 0.5% of Phosphate B complex was added The optimum cooking condition of Kamaboko to get good texture was heating for 20 minutes at 12$0^{\circ}C$.

• 대한기계학회논문집A
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• 제23권7호
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• pp.1196-1204
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• 1999

adaption of the model predictions is highly desirable. In general, the width deviation at the head and tail ends of strip may be different from that of the steady state region. Therefore, the dynamic edger corrections can be used to compensate the width deviations which would otherwise occur. For the precise width control, the effect of edger roll gap and rolling conditions on the width deviation of head and tail ends of strip has been investigated and the effective method to decrease width deviation has been proposed. On-line application of dynamic edger control method in this study shows about 50% width compensation at the head end of the strip, and near perfect compensation at the tail end of strip.

• 한국가시화정보학회지
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• 제13권1호
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• pp.9-14
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• 2015

There have been many attempts to reduce the cost of transportation. Especially, drag reduction of heavy vehicles has enormous influence on energy saving by reducing the driving power of the vehicles. In this study, the effects of drag-reducing additive devices such as side skirt, boat tail and cab-roof fairing on the drag reduction of a 5 ton truck model were experimentally investigated. The aerodynamic performance of these flow-control devices attached to heavy vehicle was evaluated through wind tunnel test. In addition, flow patterns around the truck model were visualized by using smoke tube method. The drag coefficient is reduced by up to 5.7%, 7.16% and 22.2% by the side skirt, boat tail and cab-roof fairing, respectively. The interactive effect of the side skirt and boat tail was also investigated.

• Clinical and Experimental Reproductive Medicine
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• 제25권1호
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• pp.1-8
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• 1998

항정자항체의 종류 및 존재부위가 정액성상 및 수정능력에 미치는 영향을 조사하였다. 항정자항체의 종류 및 존재부위는 immunobead binding test에 의하여 시행하였으며, 정자와 수정능력은 투명대제거 햄스터 난자 침입법에 의하여 시행하였다. 항정자항체는 정자수, 운동성 및 운동지수에 악영향을 끼쳤으며, 수정능력에도 악영향을 끼쳤다. 항정자항체의 존재부위에 따른 차이는 보이지 않았다. 항정자항체 IgG가 정자두부 혹은 정자미부에 존재할 경우 및 항정자항체 IgA가 정자미부에 존재할 경우 수정능력을 크게 감소시켰다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2010년도 학술발표회
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• pp.571-575
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• 2010

Drought is a natural hazard with different properties that are usually dependent to each other. Therefore, a multivariate model is often used for drought frequency analysis. The Copula based bivariate drought severity and duration frequency analysis is applied in the current study in order to show the effect of tail behavior of drought severity and duration on the selection of a copula function for drought bivariate frequency analysis. Four copula functions, namely Clayton, Gumbel, Frank and Gaussian, were fitted to drought data of four stations in Iran and Canada in different climate regions. The drought data are calculated based on standardized precipitation index time series. The performance of different copula functions is evaluated by estimating drought bivariate return periods in two cases, [$D{\geq}d$ and $S{\geq}s$] and [$D{\geq}d$ or $S{\geq}s$]. The bivariate return period analysis indicates the behavior of the tail of the copula functions on the selection of the best bivariate model for drought analysis.

• The Korean Journal of Physiology and Pharmacology
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• 제3권6호
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• pp.615-621
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• 1999

In spite many evidences has supported the cardioprotective effect of bradykinin, its direct effects at the cell level are still under question. We investigated the both effects of bradykinin (BK) on $Ca^{2+}-related$ ionic currents using whole cell voltage clamp technique in rabbit cardiomyocytes and on the intracellular $Ca^{2+}$ transient using calcium sensitive fluorescence dye, indo-1AM. Simultaneously with recording intracellular $Ca^{2+}$ transients, cell contractility was estimated from the changes in length of the electrical stimulated rat cardiac myocytes. L-type $Ca^{2+}$ current decreased by bradykinin at the entire voltage range. Inward tail current increased initially up to its maximum about 4 min after exposing myocytes to BK, and then gradually decreased again by further exposure to BK. This tail current decreased remarkably at washing BK off but slowly recovered ca. 20 min later. The change in cell contractility was similar to that in tail current showing initial increase followed by gradual decrease. Removal of BK brought remarkable decrease in contractility, which was recovered $15{\sim}20$ min after cessation of electrical stimulation. Bradykinin increased $Ca^{2+}$ transient initially but after some time $Ca^{2+}$ transient also decreased coincidentally with contractility. From these results, it is suggested that bradykinin exerts directly its cardioprotective effect on the single myocytes by decreasing the intracellular $Ca^{2+}$ level followed by an initial increase in $Ca^{2+}$ transient.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.565-568
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• 2002

In the flow analysis around a bluffbody such as road vehicles, drag reduction has been of the primary concern mainly due to the effect on fuel economy. To reduce the drag, which is mostly due to the pressure difference caused by the flow separation, the location of the separation and eddy sizes are controlled. However, less attention has been given to the effect of the lift. The effect of lift may cause the driving stability problem of the vehicle at high speed white heavy downward effect of lift together with the vehicle weight may require more power to drive the vehicle forward. It is considered worthwhile to pursue the optimal design of the low drag tail shape of the MIRA model while taking the lift effect into account, even though it is considered as a reference. To this end, a commercial multi-objective optimization code, FRONTIER, Is used together with the CFD code, STAR-CD. It is hoped that the results will provide more insight into the flow field around the bluffbody as transportation means.