• Title/Summary/Keyword: value of time

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Estimation of Interregional Mode Choice Models and Value of Travel Time Accommodating Taste Variation of Individuals (개인의 선호다양성을 고려한 지역간 수단선택 모형 구축 및 시간가치 추정 연구)

  • Cho, Shin-hyung;Seo, Young-hyun;Kho, Seung-young;Rhee, Sung-mo
    • Journal of the Korean Society for Railway
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    • v.20 no.2
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    • pp.288-298
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    • 2017
  • The system of high-speed and conventional railway vehicles is diversified, and significant technological development in performance has been achieved. This study analyzed the modal change characteristics; furthermore, it estimated the value of travel time by improving the travel time and cost for the passenger's perception of railway. In this study, we formulate a mode choice model for passengers and compare it with the mixed logit model which reflects individual taste variation. In addition, the validity of the analysis is presented through an estimation the value of travel time using the derived model. For this purpose, a stated preference survey was conducted with 510 people using public transportation. The benefits of time-saving can be accurately determined by estimating the value of time spent on the railway. Appropriate fares for public transportation can also be estimated.

Export Container Remarshaling Planning in Automated Container Terminals Considering Time Value (시간가치를 고려한 자동화 컨테이너 터미널의 수출 컨테이너 이적계획)

  • Bae, Jong-Wook;Park, Young-Man;Kim, Kap-Hwan
    • Journal of the Korean Operations Research and Management Science Society
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    • v.33 no.2
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    • pp.75-86
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    • 2008
  • A remarshalling is one of the operational strategies considered importantly at a port container terminal for the fast ship operations and heighten efficiency of slacking yard. The remarshalling rearranges the containers scattered at a yard block in order to reduce the transfer time and the rehandling time of container handling equipments. This Paper deals with the rearrangement problem, which decides to where containers are transported considering time value of each operations. We propose the mixed integer programming model minimizing the weighted total operation cost. This model is a NP-hard problem. Therefore we develope the heuristic algorithm for rearrangement problem to real world adaption. We compare the heuristic algorithm with the optimum model in terms of the computation times and total cost. For the sensitivity analysis of configuration of storage and cost weight, a variety of scenarios are experimented.

Oxidative Stability of Hydrated Soybean Oil during Heating at High Temperature (고온가열 과정 중 대두경화유의 산화안전성에 관한 연구)

  • Kim, Myong-Ae
    • Journal of the Korean Society of Food Culture
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    • v.23 no.1
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    • pp.26-32
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    • 2008
  • : In this experiment, three samples of oils were used. These oils were hydrated soybean oil, pure soybean oil and regular soybean oil. Oil was used after heating at $235-240^{\circ}C$ every four hours term and total heating hours was 16 hours. The physio-chemical analysis and sensory evaluation were performed on these oils. The hydrated soybean oil showed lower acid, peroxide and carbonyl value than the other two oils (p<0.05 or p<0.001). The other two oils were more affected in rancidity than the hydrated soybean oil. In color test, whereas L value lowed during the heating time, a and b value increased during the heating time. The tendency of high L value and low b value in a long-time heating was more apparant on the pure soybean oil and the regular soybean oil than on the hydrated soybean oil (p<0.05). In sensory evaluation, color and rancidity order increased during the heating time. The hydrated soybean oil showed color and rancidity order than the other two oils. In overall quality test, the pure and regular soybean oil that had been used for 12 and 16 hour were not preferable. The hydrated soybean oil that had been used for 16 hour were not preferable. In sensory evaluation, the hydrated soybean oil, the pure and regular soybean oil did not show a apparent difference, although the hydrated soybean oil had a little better scores on the overall quality.

Lightweight Algorithm for Digital Twin based on Diameter Measurement using Singular-Value-Decomposition (특이값 분해를 이용한 치수측정 기반 디지털 트윈 알고리즘 경량화)

  • Seungmin Lee;Daejin Park
    • IEMEK Journal of Embedded Systems and Applications
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    • v.18 no.3
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    • pp.117-124
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    • 2023
  • In the machine vision inspection equipment, diameter measurement is important process in inspection of cylindrical object. However, machine vision inspection equipment requires complex algorithm processing such as camera distortion correction and perspective distortion correction, and the increase in processing time and cost required for precise diameter measurement. In this paper, we proposed the algorithm for diameter measurement of cylindrical object using the laser displacement sensor. In order to fit circle for given four input outer points, grid search algorithms using root-mean-square error and mean-absolute error are applied and compared. To solve the limitations of the grid search algorithm, we finally apply the singular-value-decomposition based circle fitting algorithm. In order to compare the performance of the algorithms, we generated the pseudo data of the outer points of the cylindrical object and applied each algorithm. As a result of the experiment, the grid search using root-mean-square error confirmed stable measurement results, but it was confirmed that real-time processing was difficult as the execution time was 10.8059 second. The execution time of mean-absolute error algorithm was greatly improved as 0.3639 second, but there was no weight according to the distance, so the result of algorithm is abnormal. On the other hand, the singular-value-decomposition method was not affected by the grid and could not only obtain precise detection results, but also confirmed a very good execution time of 0.6 millisecond.

A Study on the Heated Edible Oils(II) -Flow Properties and Changes of Fatty Acid Compositions on the Rice Bran Oil- (가열식용유(加熱食用油)에 관(關)한 연구(硏究)(II) -미(米)강유(油)의 유동성(流動性)과 지방산변화(脂肪酸變化)에 관(關)해서-)

  • Kim, Eun-Ae;Jeong, Tae-Myoung;Kim, Haeng-Ja;Park, Jea-Ok
    • Journal of Nutrition and Health
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    • v.11 no.1
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    • pp.33-37
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    • 1978
  • The effect of heating time (0 to 30 hours at $180{\pm}5^{\circ}C$) on the change of flow properties, fatty acid compositions and some other characteristics such as acid value, iodine value, peroxide value and density of purified edible rice bran oil were observed. flow properties were measured with Maron-Belner type capillary viscometer. Newtonian motion was observed in non-heated oil and the oil heated for 5 hours but non-Newtonian motion was observed in the oil heated for more than 10 hours and at high shear stress. The fatty acid compositions were analyzed by gas liquid chromatography and all the components of fatty acids were reduced in amounts with extention of heating time. The acid value, peroxide value and density were increased but iodine value were decreased with extension of heating time.

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A Clinical Study on Children with Excessive Sweating (소아(小兒) 한증(汗症)에 대한 임상적(臨床的) 고찰(考察))

  • Yoon, Ji-Yeon;Kim, Yun-Hee
    • The Journal of Pediatrics of Korean Medicine
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    • v.17 no.1
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    • pp.157-168
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    • 2003
  • The purpose of this study was to evaluate clinical characteristic and correlation with growth and weakness of children with excessive sweating. The study was progressed in children with excessive sweating who visited Dong-Eui Oriental Medical hospital from may to june, 2003. The results were as follows: 1. The growth numerical value on height and weight of children with excessive sweating was normal range ( height: p-value=0.089 >0.05, weight: p-value= 0.622>0.05). 2. In sweating region, head and neck 46.7%, forehead 23.3%, whole body 16.7%, back 10.0%, hand and foot 3.3%. In sweating time, sleeping 53.3%, acting 20.0%, uncertainty 20.0%, eating 3.3%, tense situation 3.3%. 3. In family history of excessive sweating, 'yes' was 65.2%, 'no' was 34.8%. 4. The growth numerical value on height did not concerned with sweating region and time, but in group in 75 marks, 'head and neck' was many. 5. The growth numerical value on weight have no concern with sweating region, but sweating time(F=3.312, p-value=0.026

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Effects of cultivar and harvest days after planting on dry matter yield and nutritive value of teff

  • Saylor, Benjamin A;Min, Doohong;Bradford, Barry J
    • Journal of Animal Science and Technology
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    • v.63 no.3
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    • pp.510-519
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    • 2021
  • One of the most pressing issues facing the dairy industry is drought. In areas where annual precipitation is low, irrigation for growing feed presents the greatest water-utilization challenge for dairy producers. Here, we investigated the effects of cultivar and harvest days after planting (DAP) on dry matter (DM) yield and nutritive value of teff (Eragrostis tef), a warm-season annual grass native to Ethiopia that is well adapted to drought conditions. Eighty pots were blocked by location in a greenhouse and randomly assigned to four teff cultivars (Tiffany, Moxie, Corvallis, and Dessie) and to five harvest times (40, 45, 50, 55, or 60 DAP). Cultivars had no effect on DM yield and nutritive value. As harvest time increased from 40 to 60 DAP, DM yield and ash-free neutral detergent fiber (aNDFom) concentrations increased, while crude protein (CP) concentrations and in vitro NDF digestibility decreased. To assess carryover effects of time of harvest on yield and nutritive value, two additional cuttings were taken from each pot. Increasing first-cutting harvest time decreased CP concentrations in the second cutting and reduced DM yields in the second and third cutting. Harvesting teff between 45 and 50 DAP best optimized forage yield and nutritive value in the first and subsequent cuttings.

Study on Space-Time Adaptive Processing Based on Novel Clutter Covariance Matrix Estimation Using Median Value (중위수를 이용한 새로운 간섭 공분산 행렬의 예측이 적용된 Space-Time Adaptive Processing에 대한 연구)

  • Kang, Sung-Yong;Jeong, Ji-Chai
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.21 no.1
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    • pp.20-27
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    • 2010
  • In this paper, we presented a signal model of STAP and actual environment of clutter. The novel estimation method of clutter covariance matrix using median value is proposed to overcome serious performance degradation after NHD in nonhomogeneous clutter. Eigen value characteristic is improved through diagonal loading. Target detection ability and SINR loss of the proposed method though MSMI statistic is also compared with conventional method using average value. The simulation results, confirm the proposed method has better performance than others.

The Effect of Various Cereal Flours on Quality and Storage Characteristics of Sausage (곡류가루 첨가가 소시지의 품질 및 저장성에 미치는 영향)

  • 조은자;장선문;임지숙
    • Journal of the East Asian Society of Dietary Life
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    • v.14 no.3
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    • pp.265-274
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    • 2004
  • To investigate the effect of cereal powders on the quality and storage characteristics of sausage, Aw, pH, microbial count, TBA value, VBN value, textual and sensory characteristics were examined. Water activity tended to decrease as storage time prolonged and all the samples showed higher Aw's than that of the control. During the storage period, pH values of all the samples decreased. L, a and b values had a tendency to decrease during the storage period. During the four weeks storage at 4$^{\circ}C$, TBA and VBN values of all the sample showed increasing tendency and were lower than those of the control. Total plate counts of bacteria, the number of lactic acid bacteria and coliform bacteria counts increased as the storage time prolonged. Texture characteristics of all samples increased up to 1 week storage and decreased subsequently. The sensory scores of all the samples decreased as the storage time prolonged.

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A Study on the Solidification Characteristics of CV Graphite Cast Iron (CV흑연주철(黑鉛鑄鐵)의 응고특성(凝固特性)에 관한 연구(硏究))

  • Chun, C.C.;Kim, S.Y.;Lee, G.W.
    • Journal of Korea Foundry Society
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    • v.5 no.3
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    • pp.5-12
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    • 1985
  • Many researchers have studied the eutectic solidification of CV Graphite Cast Iron qualitatively. However quantative studies have not been done. The type of eutectic solidification of CV Graphite Cast Iron treated with CG Alloy (Fe-Si-Mg-5Ti-Ca-Ce) was studied quantitatively through M.D.E. value (Mushy Degree of Eutectic Solidification) = $t_2/t_1)$, where $t_1$ is the difference of the eutectic solidification starting time between surface and center part of the casting sample, and $t_2$ is the time of eutectic solidification of the center part. Following results were obtained. (1) The M.D.E. value of CV graphite cast iron lies between that of spheroidal graphite and that of flake graphite cast iron but is closer to that of Flake graphite cast iron. (2) The M.D.E. value of CV graphite cast iron depends upon CV ratio. (3) The time required for eutectic solidification increases as graphite form is changed from Flake, CV. to spheroidal graphite. (4) The M.D.E. value increases as cooling rate increases.

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