• 한국태양에너지학회 논문집
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• 제29권5호
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• pp.20-27
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• 2009

The effect of borehole thermal resistance on the borehole length is studied. In performing this work a new concept BLRR(borehole length reduction rate) is developed based on the line source model. The solution of line source model is shown to be valid through the comparison with the data of thermal response test. It is shown that BLRR is a function of soil thermal conductivity(k) and borehole thermal resistance($R_b$). The value of BLRR increases with increasing k, which means reducing $R_b$ is more effective when k is high. The reduction of borehole length with change of $R_b$ is easily estimated with BLRR. The validity of BLRR is also examined with EED analysis.

• 대한한방부인과학회지
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• 제24권3호
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• pp.73-84
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• 2011

Objectives: This study examined the recent update of factors affect length and regularity of menstrual cycle and symptoms need for diagnosis in oriental medicine. Methods: For factors, we searched the key word "menstrual cycle length and factor" in ScienceDirect(http://www.sciencedirect.com) and we mainly searched symptoms in the journal of oriental obstetrics & gynecology and text. Results: The result are shown in the Table 1-3. Conclusion: In fact as the fluctuation of menstrual cycle length and regularity is very high in healthy women, we must observe the factor affect menstrual cycle with attention even though rule out disease, operation and HRT etc. these researches show potential to compound oriental medicine care and factor of menstrual cycle change.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.1503-1510
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• 2011

The dropper length calculation method about the normal same encumbrance spans is well known independent to whether the pre-sag is given or not. But, the dropper length calculation method for the elevating span which consists in the end area of a tensioning section and normally consists with overlaps is not well known. In this study, firstly, we investigate the dropper length calculation method about the elevating span whether the insulator is contained in or not, we also recognize the effect of dropper length due to the change of the take-off point. Secondly, we very this calculation method with a catenary sample data and check again with Gyeongbu HSL design data.

• 한국해양공학회지
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• 제18권2호
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• pp.46-51
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• 2004

Natural frequencies of the transverse vibration of beams with step change in cross-section are obtained by using the asymptotic closed form solution. This closed form solution is found by using WKB method under the assumption of slowly varying properties, such as mass, cross-section, tension etc., along the beam length. However, this solution is found to be still very accurate even in the case of large variation in cross-section and tension. Therefore, this result can be easily applied to many engineering problems.

• 한국환경농학회지
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• 제34권3호
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• pp.192-195
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• 2015

BACKGROUND: The growing season (GS) has been understood as a useful indicator for climate change due to high relationship with increasing temperature. Hear this study was conducted to examine changes in the thermal GS over South Korea from 1970 to 2013 based on daily mean air temperature for assessing the temporal and spatial variability in GS. METHODS AND RESULTS: Three GS parameters (starting date, ending date, and length) were determined at 19 stations throughout South Korea. The results show that the GS has been extended by 4.2 days/decade between 1970 and 2013 on average. The growing season start (GSS) has been advanced by 2.7 days/decade and the growing season end (GSE) has been delayed by 1.4 day/decade. Spatial variation in the GS parameters in Korea are shown. The GS parameters, especially GSS, of southeastern part of Korea have been changed more than that of northwestern part of Korea. The extension of GS may be more influenced on earlier onset in spring rather than later GSE. CONCLUSION: Under climate change scenarios, the GS will be more extended due to delayed GSE as well as advanced GSS. And These are more notable in the northeastern part of Korea.

• 비파괴검사학회지
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• 제19권1호
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• pp.8-15
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• 1999

교류전위차법 (alternating current potential drop : ACPD)을 이용하여 이차원 표면균열을 갖고 있는 강자성체 (ferromagnetic material)와 상자성체 (paramagnetic material)의 모드 I (opening mode) 응력확대계수($K_I$)를 효과적으로 계측하는 방법을 개발하기 위하여 하중에 따른 교류전위차 변화(change in ACPD)에 미치는 자속(magnetic flux)의 영향을 연구하였다. 그리고 하중에 따른 전위차 변화에 미치는 탈자(demagnetization) 및 균열길이의 영향을 연구하였다. 기전력을 많이 유도할 수 있도록 설계된 계측계의 경우 하중에 따른 교류전위차 변화량은 크게 증가하였다. 아울러 교류전위차 변화와 응력확대계수 변화 사이의 관계는 탈자 등의 조치가 없어도 선형적이며, 탈자는 전위차 변화에 거의 영향을 미치지 않았다. 일정 $K_I$ 변화에 의한 전위차 변화량은 균열길이에 의존하지 않고 계측계에 의존한다. 교류전위차법을 이용하여 효과적으로 응력확대계수를 결정하는 방법은 기전력을 많이 유도할 수 있도륵 설계된 계측계를 사용하여 교류전위차 변화를 측정하는 것이다.

• 한국의류학회지
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• 제17권4호
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• pp.539-549
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• 1993

The purpose of this study was to find out the moving fitness and slit length of tight skirt in relation to its length & silhouette. Five kinds of length, micro mini, mini, natural line, medi and maxi, and two kinds of siihuette, slim & straight-a total of ten tight skirts-were investigated. Ten college students were chosen for this experiment. The moving fitness was tested by measuring the step length, step width and step angle in the case of walking on the flat and going up the stairway & bus stair. The slit length was tested by measuring the back slit length needed in the case of going up stairway & bus stair. Data were analyzed with use of SAS pakage. The statistics were based on average, standard diviation, two-way ANOVA, Pearson's correlation and multiple regression analysis. The main results were as follows. 1. There was significant difference in the moving fitness according to length & silhouette of tight skirt. The moving fitness of slim type was lower than that of straight type and the longer the skirt length was, the lower the moving fitness was. The significance appeared particularly in the case of going up the bus stair. 2. There was significant difference in the skirt length obove slit accorting to length & silhouette of tight skirt. The skirt length obove slit of slim type was shorter than that of straight type. The longer skirt length was, the longer it was from micro mini to natural line, that of medi skirt was shorter or a little longer than that of natural line skirt and there was little change from medi skirt to maxi skirt.

• 대한토목학회논문집
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• 제31권4D호
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• pp.527-538
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• 2011

현재 버스정류장 설치기준은 연속류가 주를 이루는 간선도로에 대한 기준만 제시되어 있는 실정으로, 버스운행 특성과 보행자 특성을 고려한 버스정류장의 설치방법에 관한 명확한 기준이 전무하다. 특히, 버스정류장의 위치나 형태가 부적절하게 설치 운영될 경우, 버스운전자를 포함한 도로이용자는 물론 보행자에게도 큰 위험과 불편을 초래하게 된다. 이에 본 연구는 원활한 교통소통과 더불어 버스운행 특성과 보행자 특성, 그리고 교통안전을 고려한 신호교차로 버스정류장의 합리적인 설치방법을 제시하였다. 첫째, 버스정류장의 위치에 따라 유입부와 유출부로 구분하고, 버스정류장의 적정길이는 변속차로가 통합/분리된 형태에 따라 교통소통을 고려하여 산정하였다. 둘째, 다양한 유형의 버스정류장 적정길이는 보행자 특성을 고려하여 적정형태를 선택하였다. 셋째, 교통소통과 보행자 특성을 고려하여 산정된 버스정류장 길이에 대하여 교통안전을 고려하여 버스정류장 설치위치의 적정성 여부를 판단하였다. 본 연구에서 제시한 교통소통, 보행자 특성, 교통안전 등을 종합적으로 고려한 버스정류장 설치방법은 버스정류장 설치기준 제시 및 안전하고 쾌적한 버스정류장 조성에 이바지 할 수 있을 것이다.

• Journal of Chest Surgery
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• 제18권1호
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• pp.1-6
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• 1985

Isolated sinus node cells of the rabbit were used to assess the effects of extracellular Na, K, Ca and Mg concentrations on cardiac pacemaker activity. With intracellular glass micro-electrodes spontaneous action potentials of SA node were recorded and the effects of various ions and their blockers were analyzed in terms of the cycle length, the amplitude and the duration of action potentials, the results obtained were as follows. 1. Sodium reduction [up to 30%] decreased the amplitude of action potential and lengthened the cycle length. TTX, specific blocker of Na channel slightly lengthened the cycle length. 2. Increasing potassium ion concentration, the duration of action potential decreased and the frequency increased in 6mM, however, spontaneous action potential was stopped in 24 mM. Barium ion known to be decreasing K conductance increased the duration of action potential but no significant change in the cycle length was noticed. 3. Calcium ion has shortening effect on the duration and the cycle length of action potential but not with dose-dependent manner. Cadmium ion .[0.02mM] lengthened cycle length and the duration of action potential. 4. Increasing the concentration of magnesium ion the cycle length was lengthened, significantly.

• 대한치과교정학회지
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• 제25권6호
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• pp.655-664
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• 1995

Sixty male patients with polysomnographically documented OSA were included in this study. A pair of cephalograms were obtained in the upright and supine positions. In the supine position, the ANB angle, lower facial height and the cross-sectional area of soft palate increased and there was a decrease in the vertical airway length and oropharynx cross-sectional area. Positional changes did not affect the cross-sectional area of tongue, but the cross-sectional area of the oropharynx decreased in the supine position. The obese group had higher AI and RDI. Maxillary unit length, C3-H, the cross-sectional areas of tongue, soft palate and oropharynx were significantly greater in the group Obese than in non-obese group. No correlation was noted between the mandibular unit length and OSA severity, The group of small mandibular unit length showed shorter lower facial height and maxillary unit length, and smaller cross-sectional area of tongue than the long mandibular unit length group. Hyold bone positioned more inferiorly and cross-sectional area of nasopharynx decreased as the OSA severity increased.