• 충청수학회지
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• 제21권1호
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• pp.99-106
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• 2008

In this paper, we establish some recurrence relations which is satisfied by the quotient moments of the lower record values from the standard generalized extreme value (GEV) distribution.

• 한국산업융합학회 논문집
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• 제5권2호
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• pp.103-110
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• 2002

An artificial neural network is applied to the prediction of compressive strength, slump value of concrete. Standard mixed tables arc trained and estimated, and the results are compared with those of experiments. To consider the varieties of material properties, the standard mixed tables of two companies of Ready Mixed Concrete are used. And they are trained with the neural network. In this paper, standard back propagation network is used. For the arrangement on the approval of prediction of compressive strength and slump value, the standard compressive strength of 210, $240kgf/cm^2$ and target slump value of 12, 15cm are used because the amount of production of that range arc the most at ordinary companies. In results, in the prediction of compressive strength and slump value, the predicted values are converged well to those of standard mixed tables at the target error of 0.10, 0.05, 0.001 regardless of two companies.

• 암석학회지
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• 제14권4호
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• pp.237-250
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• 2005

ICP-MS로 화강암질 암석내 희토류원소의 함량 분석시 표준시료의 선택이 어느 정도 영향을 주는 지를 밝혀내기 위해, 상업용 표준시료(ACCU-standard, No. Cal-1), 화강암의 한국산 표준시료(KG-1), 미국산 표준시료(G-2), 일본산 표준시료(JC-1a, JC-2)를 각각 기준시료로 하여 각각의 희토류원소 함량을 측정하였다. 실험결과에 의하면, 경희토류(La-Gd) 분포도는 표준시료의 변화에 관계없이 대체적으로 추천값과 측정값 모두 일치하였다. 그러나 G-2 혹은 JG-2를 기준으로 측정했을 시, 다른 표준시료의 추천값과 측정값에 의한 중희토류(Gd-Lu)의 분포도는 많은 차이가 발생되었다. 이는 표준시료의 추천값의 오류 혹은 표준시료 암석의 지구화학적 특성에 기인된다. KG-1 혹은 JG-1a를 기준시료로 하여 희토류원소 함량을 측정했을 경우에는 G-2나 JG-2를 기준시료로 했을 때보다 추천값과 측정값에 의한 희토류원소의 분포도의 어긋남이 비교적 약한 편이다. 이는 국내 화강암류의 희토류원소 함량분석에 있어서의 표준시료로서 KG-1 혹은 JG-1a가 보다 더 유용함을 지시해준다.

• Journal of Mechanical Science and Technology
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• 제20권10호
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• pp.1662-1669
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• 2006

Since randomness and uncertainties of design parameters are inherent, the robust design has gained an ever increasing importance in mechanical engineering. The robustness is assessed by the measure of performance variability around mean value, which is called as standard deviation. Hence, constraints in robust optimization problem can be approached as probability constraints in reliability based optimization. Then, the FOSM (first order second moment) method or the AFOSM (advanced first order second moment) method can be used to calculate the mean values and the standard deviations of functions describing constraints and object. Among two methods, AFOSM method has some advantage over FOSM method in evaluation of probability. Nevertheless, it is difficult to obtain the mean value and the standard deviation of objective function using AFOSM method, because it requires that the mean value of function is always positive. This paper presented a special technique to overcome this weakness of AFOSM method. The mean value and the standard deviation of objective function by the proposed method are reliable as shown in examples compared with results by FOSM method.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.1043-1048
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• 2006

This paper aimed to verify and develop lighting design data for offices in Korea. It focused on a Korean standard office value relative to lighting density and the evaluation of lighting energy and cooling load. When planning indoor lighting design, we generally utilize the lighting density value which is set $14W/m^2$ by the ASHRAE/IES standard office value. However, the value is not appropriate to apply in Korea where higher efficiency lamps are more popular than others. For calculation of a proper lighting density of Korea, we analysed distribution curves of luminous intensity(2-lamp fluorescent lighting fixture with Parabolic) and derived the new lighting density $12.64W/m^2$ as Korea standard office value. In the simulation using this value, it was shown that lighting energy and cooling load could be reduced.

• 한국IT서비스학회지
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• 제12권3호
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• pp.1-21
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• 2013

This study attempts to explain the mechanism behind the migration from vertically integrated value chain architecture to an innovation ecosystem consisting of horizontally separated layers in value chain. We first present a comprehensive framework based on the theoretical analysis of the drivers for migration to an innovation ecosystem, which are standard (institution), capability distribution, and transaction costs. The theoretical framework suggests that the migration to an innovation ecosystem is explained by the influence of standard on the evolutionary change of capability distribution and transaction costs. In particular, when the new de-jure standard competes with the de-facto standard, the new de-jure standard has the greatest impact on the distribution capabilities and the transaction costs. Based on this theoretical framework, we analyze the latest SDN (Software Defined Networking) case of the network industry. SDN standard has transformed the industry from a vertically integrated value chain architecture to a horizontally separated one with its influence on the distribution capabilities and the transaction costs in the industry.

• 한국의류산업학회지
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• 제21권2호
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• pp.203-208
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• 2019

This paper considers the moisture permeability and fashion in the upper fabrics of cotton fabric shoes woven into various tissues and properties measured to examine the use as upper fabrics. We measured the tissues of the manufactured upper fabric are 1/3 twill, $4{\times}4$ weft rib, Maya, Triple, Deformed twill design (DTD), Diamond tissues and tear strength, tensile strength, breaking elongation, stretching under load at 100N, stitch tear resistance, and fastness. In the case of $4{\times}4$ weft rib, the tear strength and tensile strength were excellent; however, the elongation and stitch tear resistance at 100N load were less than the standard value. DTD fabrics are characterized by physical properties in the warp direction that are superior to those in the weft direction; however, the tear strength and tensile strength in the weft direction are less than the standard value. The 1/3 twill fabrics showed high tensile strength value and stitch tear resistance value in the warp direction; however, toughness, the main property of the shoe upper, was below the standard value. Triple and diamond fabrics, which have a significant effect on the performance of the shoe upper fabric, also had less than the standard value of tear strength. Maya upper fabric for shoes has better properties than other upper fabrics except for the elongation at break, and the stitch tear resistance has a value of 178% in the warp direction and 214% in the weft direction compared to the standard value. Therefore, the Maya fabric showed the possibility of being used as an upper textile for shoes.

• 한국산업융합학회 논문집
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• 제24권3호
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• pp.307-313
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• 2021

In this study, the comparative analysis, among the design standard value of distribution power, the calculated value from the measurement data of strand and the empirical data of the distribution line itself, have been performed for the elastic coefficients and linear expansion coefficients of distribution line conductors. The empirical values of elastic coefficients were lower about 10.6%(892kgf/mm²) than those of the design standard value of the distribution power and there were a little difference between the empirical values of linear expansion coefficients and the design standard value of the distribution power. From the above results, it could be concluded that the empirical values of conductor characteristics should be used in the dip design and installation of distribution line.

• 대한수의학회지
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• 제14권2호
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• pp.173-177
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• 1974

Thirty of healthy non-pregnant Holstein cows being raised in the vicinity of Daejeon, which had been delivered of calves 4 to 6 times since they were imported to Korea, were selected with the purpose of serum chemical analysis. Total protein, albumin, globulin, total cholesterol, urea nitrogen and glucose and A/G ratio were investigated. The results of present investigation were summarized as follows: 1. Ranges and mean values (with standard error) of total protein, albumin and globulin were 6.87~8.58g/100ml, $7.75{\pm}0.60g/100ml$; 2.6~3.5g/100ml(37.1~45.0%), $3.26{\pm}0.27g/100ml$(40.1%); and 3.78~5.48g/100ml(55.1~64.6%), $4.51{\pm}0.43g/100ml$(58.1%), respectively. 2. Range and mean value (with standard error) of A/G ratio were 0.52~0.86 and 0.73~0.093. 3. Range and mean value (with standard error) of glucose were 35~50mg/100ml and $45.2{\pm}9.1mg/100ml$. 4. Range and mean value(with standard error) of total cholesterol were 122~228mg/100ml and $194.6{\pm}11.1mg/100ml$. 5. Serum urea nitrogen showed that the range of 10.5~15.1mg/100ml and the mean value(with standard error) of $12.7{\pm}1.5mg/100ml$.

• 한국주거학회논문집
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• 제23권5호
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• pp.61-73
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• 2012

This study applied the value of floor-area-ratio standard calculation method to case areas and analyzed them to overcome the limits of previous studies in calculation methods for area standards and land price (value) standard development rights. The results are presented as follows: First, criteria to select sending areas and receiving areas are needed. Second, calculation methods based on the value of floor-area-ratio standard can be widely used as standardized criteria in various areas. Third, for the connection of sending areas with receiving areas, the connections of 1:1, n:1, 1:n, and n:n are available and the location of possible dealing areas should be considered. Also, the choice of connecting unions that meet the purpose of TDR presented by local governments is available. Fourth, for Gwangju, as receiving areas downtown provide higher profits than previous renewal projects, the application of TDR is available. Application methods to overcome problems are presented as follows: First, criteria to select sending and receiving areas should be prepared and implemented in an order of priority. Second, in calculating development rights, methods based on the value of floor-area-ratio standard should be used. Third, the standards and principles of sending and receiving areas should be designated and possible dealing areas should not be limited.