• Title/Summary/Keyword: Standard value

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The Prediction of Compressive Strength and Slump Value of Concrete Using Neural Networks (신경망을 이용한 콘크리트의 압축강도 및 슬럼프값 추정)

  • Choi, Young-Wha;Kim, Jong-In;Kim, In-Soo
    • Journal of the Korean Society of Industry Convergence
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    • v.5 no.2
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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.

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A Role of Standard Material in Rare Earth Element Analysis by ICP-MS (ICP-MS를 이용한 희토류원소 분석시 표준시료의 선택이 미치는 영향)

  • Lee Seung-Gu;Kim Kun-Han;Song Yong Sun;Kim Yongje
    • The Journal of the Petrological Society of Korea
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    • v.14 no.4 s.42
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    • pp.237-250
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    • 2005
  • In order to clarify the effect of standard rock material in the chemical analysis of rare earth element abundance with ICP-MS, we measured rare earth element abundance of KIGAM granite standard rock material (KG-1), USGS granite standard rock material (G-2), GSJ granite standard rock materials (JG-1a and JG-2). In REE analysis, we used conventional calibration standard solutions, KG-1, JG-1a, JG-2 and G-2 as standard material, respectively. Chondrite-normalized LREE patterns of low granite standard material correspond well each other in the recommended value and the estimated value regardless of a kind of standard rock. However, the HREE patterns of the estimated value based on G-2 or JG-2 and the recommended value are different from each other. Such difference may be due to the wrong recommended value or a specific geochemical properly of the standard rock material itself, The chondrite-normalized REE patterns of four standard rock materials estimated on the basis of KG-1 or JG-1 a show little deviation compared to the those of the recommended values. This suggests that KG-1 and JG-1a may be a optimum standard material for granitoids.

A Study for Robustness of Objective Function and Constraints in Robust Design Optimization

  • Lee Tae-Won
    • Journal of Mechanical Science and Technology
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    • v.20 no.10
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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.

Verification and Development of Lighting Design Data for Office in Korea (Focused on the Evaluation of Lighting Energy and Cooling Load) (사무소를 위한 조명설계 자료의 개발과 검증 (조명에너지와 냉방부하를 중심으로))

  • Kim, Eun-Hee;Suh, Seung-Jik
    • Proceedings of the SAREK Conference
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    • 2006.06a
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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.

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Understanding the Drivers for Migration to Innovation Ecosystem : The Influence of Standard on the Evolutionary Change of Capability Distribution and Transaction Costs (혁신 생태계 변화의 동인에 대한 이론과 사례 연구 : 표준이 역량분포와 거래비용의 진화적 변화에 미치는 영향 분석을 중심으로)

  • Kim, Min-Sik;Kim, Eonsoo
    • Journal of Information Technology Services
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    • v.12 no.3
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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.

Development of High-strength Cotton Fabrics for Upper of Shoes to Improve Fashionability (패션성 향상을 위한 신발갑피용 고강도 면직물 개발)

  • Lee, Jae-Ho
    • Fashion & Textile Research Journal
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    • v.21 no.2
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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.

Empirical Study on the Dip Design and Installation of Distribution Line Conductors (배전선로의 이도설계 및 시공에 대한 실증연구)

  • Ahn, Ihn-Seok
    • Journal of the Korean Society of Industry Convergence
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    • v.24 no.3
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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.

Studies on Serum Chemical Values of Holstein Cows (Holstein 암소 혈청(血淸)의 화학성분(化學成分)에 관(關)하여)

  • Moon, Hi Cheol
    • Korean Journal of Veterinary Research
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    • v.14 no.2
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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 $12.7{\pm}1.5mg/100ml$.

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A Study on Application Methods of the Transfer of Development Rights - Focused on Residential Areas of Gwangju - (개발권양도제 적용방안에 관한 연구 - 광주광역시 주거지를 중심으로 -)

  • Jeong, Woo-Gon
    • Journal of the Korean housing association
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    • v.23 no.5
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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.