• Journal of Yeungnam Medical Science
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• 제11권1호
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• pp.63-71
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• 1994

뇌졸중이 시상하부-뇌하수체-부신축에 미치는 영향을 조사하기 위해 1992년 6월 1일부터 1993년 6월 30일까지 영남대학교 의과대학 부속병원 신경과에 입원한 뇌경색 42례, 뇌출혈 20례 등 총 62례 환자대상군과 대조군 21례를 대상으로 뇌졸중의 각 유형, 병변부위, 병변크기, 운동장애정도, 연령 및 성별 등이 DST결과에 어떤 영향을 미치는지 조사하여 다음과 같은 성적을 얻었다. 뇌경색군에서 혈청 cortisol기저치가 대조군보다 유의하게 높았고 (p<0.01), DST 비억제반응의 빈도는 뇌졸중군에서 대조군보다 유의하게 높았다(p<0.05). 뇌졸중군 중에서 좌측 대뇌반구의 병변이 DST 비억제반응의 빈도가 유의하게 높았다(p<0.01). 뇌졸중의 병변크기가 심할수록 DST 비억제반응의 빈도가 유의하게 높았으나 (P<0.01) 뇌졸중의 각 유형, 운동장애 정도, 연령 및 성별등은 DST 비억제반응의 빈도와 유의한 차이는 없었다. 이로 미루어 볼때 뇌졸중이 HPA축에 영향을 미침을 알 수 있고, 뇌졸중 유형중에는 뇌경색이 가장 많은 장애를 초래하며, 뇌졸중의 병변부위에 따라서는 좌측 대뇌반구가 가장 많은 장애를 야기하며, 병변이 클수록 더 많은 장애를 초래함을 알 수 있어 뇌졸중후 나타나는 우울증등의 시상하부와 연관된 환자에게는 항 우울제투여로 임상효과를 기대할 수 있고 향후 뇌척수액의 신경전달물질 검사 및 뇨의 catecholamine대사산물 측정 등 지속적 연구가 필요할 것으로 사료된다.

• 한국지열·수열에너지학회논문집
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• 제8권2호
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• pp.61-69
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• 2012

Geothermal heat pump(GHP) systems have been shown to be an environmentally-friendly, efficient alternative to traditional cooling and heating systems in both residential and commercial applications. Although some experimental work related to performance evaluation of GHP systems with vertical borehole ground heat exchangers for commercial buildings has been done, relatively little has been reported on the performance simulation of these systems. The aim of this study is to evaluate the cooling and heating performance of the GHP system with 30 borehole ground heat exchangers applied to an commercial building($1,210m^2$) in Seoul. For this purpose, a typical design procedure was involved with a combination of design parameters such as building loads, heat pump capacity, circulating pump, borehole diameter, and ground effective thermal properties, etc. The cooling and heating performance prediction of the system was conducted with different prediction methods and then each result is compared.

• 천문학회지
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• 제36권spc1호
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• pp.93-99
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• 2003

Various attempts have been made to explain the: pronounced seasonal and universal time (UT) variations of geomagnetic indices. As one of such attempts, we analyze the hourly-averaged auroral electroject indices obtained during the past 20 years. The AU and AL indices maximize during summer and equinoctial months, respectively. By normalizing the contribution of the solar conductivity enhancement to the AU index, or to the eastward electrojet, it is found that the AU also follows the same semiannual variation pattern of the AL index, suggesting that the electric field is the main modulator of the semiannual magnetic variation. The fact that the variation pattern of the yearly-mean AU index follows the mirror image of the AL index provides another indication that the electric field is the main modulator of magnetic disturbance. The pronounced UT variations of the auroral electrojet indices are also noted. To determine the magnetic activity dependence, the probability of recording a given activity level of AU and AL during each UT is examined. The UT variation of the AL index, thus obtained, shows a maximum at around 1200-1800 UT and a minimum around 0000-0800 UT particularly during winter. It is closely associated with the rotation of the geomagnetic pole around the rotational axis, which results in the change of the solar-originated ionospheric conductivity distribution over the polar region. On the other hand the UT variation is prominent during disturbed periods, indicating that the latitudinal mismatch between the AE stations and the auroral electrojet belt is responsible for it. Although not as prominent as the AL index, the probability distribution of the AU also shows two UT peaks. We confirm that the Dst index shows more prominent seasonal variation than the AE indices. However, the UT variation of the Dst index is only noticeable during the main phase of a magnetic storm. It is a combined result of the uneven distribution of the Dst stations and frequent developments of the partial ring current and substorm wedge current preferentially during the main phase.

• 동의생리병리학회지
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• 제27권5호
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• pp.637-643
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• 2013

Daesiho-tang (DST), Yijin-tang (YJT), Gyeoneumjisil-hwan (GJH), Ukdam-hwan (UDH), and Sojojung-tang (SJT) have been used to treat hypertension. The aim of this study was to investigate whether five formulas were effective for improving obesity in high fat diet (HFD) induced obese mice. The mice were divided into seven groups: (1) a normal diet (ND), (2) a high fat diet (HFD) (3) a HFD plus DST (HFD + DST), (4) a HFD plus YJT (HFD + YJT), (5) a HFD plus GJH (HFD + GJH), (6) a HFD plus UDH (HFD + UDH), or (7) HFD plus SJT (HFD + SJT) at 150 mg/kg/day for 7 weeks. All five formulas treatments significantly lowered blood pressure, final liver weights, and serum total triglyceride levels. The four formulas (HFD+DST, HFD+YJT, HFD+UDH, and HFD+SJT) decreased body weights. Also, HFD+DST, HFD+YJT, and HFD+UDH groups reduced abdominal and epididymal fat weights. The serum LDL-cholesterol levels were decreased in HFD+YJT, HFD+UDH, and HFD+SJT groups compared to the HFD group. These results demonstrate that five formulas ameliorated obesity.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2003년도 한국우주과학회보 제12권2호
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• pp.80-80
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• 2003

서브스톰이 진행될 때 극지방의 지자기 교란은 대류 제트 전류와 서브스톰 전류 쐐기로 구성되는 오로라 제트 전류에 기인한다. 이들은 전기장 강화를 뜻하는 AU 지수와 전기 전도도 강화를 뜻하는 AL 지수로 나타낼 수 있다. 이들 AU, AL 지수와 자기폭풍의 정도를 나타내는 Dst 지수와의 상관관계를 구해봄으로써 서브스톰이 자기폭풍의 형성에 어떻게 기여하는지 조사하였다. 이를 위하여 월별 누적 AU, 누적 │AL│ 값을 구한 뒤 월별 누적 Dst 와의 상관관계를 구하였다. 한편 IMF(Interplanetary Magnetic Field)의 남쪽 자기장 성분으로부터 지구 자기장 내에 강력한 전기장이 형성되어 자기폭풍을 형성한다는 견해가 있다. 전기장 E=V(태양풍 속도)$\times$Bs(IMF의 남쪽 자기장 성분)으로 나타낼 수 있으므로 이로부터 구한 월별 누적 전기장과 누적 Dst 값을 비교해 봄으로써 자기권 대류가 자기폭풍 형성에 어느 정도 기여하는지 조사하였다. 본 연구를 위하여 1966년부터 1987년까지 20년간의 AE(AU, AL) 지수를 이용하였으며 IMF 자료는 ACE 위성이 제공하는 행성간 자기장 자료로 1997년부터 2002년까지의 자료를 이용하였다. 본 연구의 결과는 현재 논쟁이 되고 있는 storm-substorm의 인과관계를 보다 잘 규명할 것으로 기대된다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2001년도 추계학술대회 논문집
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• pp.62-73
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• 2001

The scope of this study is focused on the survey of new logistics transportation systems in railroad and case studies of new systems such as piggyback system, bi-modal system swapbody, and double stack train(DST). Piggyback system, bi-modal system, swapbody, and double stack train are reviewed in term of technological validity and economic validity in Korea. Piggyback - trailer does pass loaded weight limits but does not pass train limits and can not utilize the existing freight cars. Piggyback - cargo trunk does pass all the criteria and could be developed by a domestic technology. But this study suggests to expand the length of train cars to 18.300mm for accommodation of two cargo trucks. Bi-modal system and swapbody do also pass. Double stack train could only pass the loaded weights and does not meet the train limit and the possibility of using existing freight cars. Domestic technology could not development DST, due to civil engineering construction limits and low standard height of electric line, which could not afford to operate DST.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 1996년도 Proceedings International Workshop on New Video Media Technology
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• pp.61-66
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• 1996

In this paper, an efficient contour coding algorithm incorporating polygonal approximation and discrete sine transform is introduced. Contour information is inevitable in content based coding, and polygonal approximation method is widely used to compress the contour information. However polygonal approximation method is not suitable when fine contour is needed. We show that the error signal of polygonal approximation can be efficiently represented using DST, that is, the contour information can be represented accurately with polygons and DST coefficients. With this contour coding scheme, the required bits to represent a contour can be reduced by about 40-50% with virtually no degradation compared to the existing chain coding method.

• 지능정보연구
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• 제1권2호
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• pp.123-137
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• 1995

Most of solution methods in scheduling attempt to generate good solutions by either developing algorithms or heuristic rules. However, scheduling problems in the real world require considering more factors such as multiple objectives, different combinations of heuristic rules due to problem characteristics. In this respect, the traditional mathematical a, pp.oach showed limited performance so that new a, pp.oaches need to be developed. Expert system is one of them. When an expert system is developed for scheduling one of the most difficult processes faced could be knowledge acquisition on scheduling heuristics. In this paper we propose a method for the acquisition of knowledge on the selection of scheduling heuristics using Dempster-Shafer Theory(DST). We also show the examples in the multi-objectives environment.

• Journal of Astronomy and Space Sciences
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• 제28권2호
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• pp.123-132
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• 2011

It is generally believed that the occurrence of a magnetic storm depends upon the solar wind conditions, particularly the southward interplanetary magnetic field (IMF) component. To understand the relationship between solar wind parameters and magnetic storms, variations in magnetic field polarity and solar wind parameters during magnetic storms are examined. A total of 156 storms during the period of 1997~2003 are used. According to the interplanetary driver, magnetic storms are divided into three types, which are coronal mass ejection (CME)-driven storms, co-rotating interaction region (CIR)-driven storms, and complicated type storms. Complicated types were not included in this study. For this purpose, the manner in which the direction change of IMF $B_y$ and $B_z$ components (in geocentric solar magnetospheric coordinate system coordinate) during the main phase is related with the development of the storm is examined. The time-integrated solar wind parameters are compared with the time-integrated disturbance storm time (Dst) index during the main phase of each magnetic storm. The time lag with the storm size is also investigated. Some results are worth noting: CME-driven storms, under steady conditions of $B_z$ < 0, represent more than half of the storms in number. That is, it is found that the average number of storms for negative sign of IMF $B_z$ (T1~T4) is high, at 56.4%, 53.0%, and 63.7% in each storm category, respectively. However, for the CIR-driven storms, the percentage of moderate storms is only 29.2%, while the number of intense storms is more than half (60.0%) under the $B_z$ < 0 condition. It is found that the correlation is highest between the time-integrated IMF $B_z$ and the time-integrated Dst index for the CME-driven storms. On the other hand, for the CIR-driven storms, a high correlation is found, with the correlation coefficient being 0.93, between time-integrated Dst index and time-integrated solar wind speed, while a low correlation, 0.51, is found between timeintegrated $B_z$ and time-integrated Dst index. The relationship between storm size and time lag in terms of hours from $B_z$ minimum to Dst minimum values is investigated. For the CME-driven storms, time lag of 26% of moderate storms is one hour, whereas time lag of 33% of moderate storms is two hours for the CIR-driven storms. The average values of solar wind parameters for the CME and CIR-driven storms are also examined. The average values of ${\mid}Dst_{min}{\mid}$ and ${\mid}B_{zmin}{\mid}$ for the CME-driven storms are higher than those of CIR-driven storms, while the average value of temperature is lower.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2004년도 한국우주과학회보 제13권1호
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• pp.93-93
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• 2004

We have examined the solar wind dynamic pressure enhancements during geomagnetic storm main phase. The Dst index has been used to identify more than 100 geomagnetic storms which occurred in the time interval of 1997 to 2001. We have selected only the events having the minimum Dst value less than -50 nT. In order to identify the pressure impact, we have looked at the low latitude ground H data as well as the solar wind pressure data themselves. (omitted)