• Title/Summary/Keyword: addition time

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통행시간과 점유율 기반의 실시간 신호운영 알고리즘 (A Real-time Traffic Signal Control Algorithm based on Travel Time and Occupancy Rate)

  • 박순용;정영제
    • 한국콘텐츠학회논문지
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    • 제16권8호
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    • pp.671-680
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    • 2016
  • 본 연구에서는 통행시간과 점유율의 융합 정보를 이용하는 새로운 실시간 신호제어 알고리즘을 제시하였다. 교통정보시스템의 통행시간 정보를 신호운영에 적용하였으며, 통행시간으로 부터 산정한 포화도를 신호제어에 이용하기 위한 프로세스를 개발하였다. 결정적 지체모형을 이용해 통행시간으로부터 대기행렬 길이를 생성하고, 대기행렬 길이를 다시 포화도로 변환하는 과정이 적용되었다. 또한 통행시간 기반 포화도와 루프검지기 포화도를 융합해 신호시간이 산정되도록 하였다. 신호제어 알고리즘의 효과평가를 위해 미시적 시뮬레이션 분석을 시행하였으며, 과포화 상태에서 기존 루프검지기 기반 실시간 신호제어 대비 최대 27%의 지체 감소 효과를 확인하였다. 또한 과포화 및 검지기 고장상황에 대한 효과적이고, 유용한 대응이 가능함을 확인하였다. 본 연구에서는 교통신호제어시스템과 교통정보시스템의 교통정보 통합이용 방안을 제시하였다는데 의의가 있겠다.

Minimizing Production Lead Time of Kanban System in a Stochatic Environment

  • Kim, Ilhyung
    • Management Science and Financial Engineering
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    • 제8권2호
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    • pp.1-20
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    • 2002
  • This paper presents a model that analyzes the impact of uncertainties in demand and processing times on the production lead time of a Kanban system. We consider the waste associated with under-production as well as over-production when we measure the production lead time. We set up an optimization model to minimize the production lead time. A simple heuristic procedure is developed to determine solutions in terms of the size of containers and the number of Kanban cards. In addition, we numerically examine the behavior of the optimal Kanban system.

고속 무선 통신을 위한 직렬 연접 시공간 LDPC 부호에 관한 연구 (Serially Concatenated Space-Time LDPC Codes for High Data Rate Wireless Communication)

  • 장혜경;이문호
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 하계종합학술대회 논문집(1)
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    • pp.335-338
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    • 2002
  • For high data rate transmission over wireless fading channels, space-time trellis ceding techniques can be employed to increase the Information capacity of the communication system dramatically. In this paper, we consider the concatenated space time LDPC (Low Density Parity Check) codes. Extra ceding gains In addition to the diversity advantage is shown to be achieved for certain space-time trellis codes transmitted over quasi-static lading channels.

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음이온계 계면활성제 존재하에서 양모직물의 알칼리 처리에 관한 연구 (A Study on Wool Fabric Treated with Anionic Surfactant and Alkali)

  • 이정순;류효선
    • 한국의류학회지
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    • 제11권2호
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    • pp.101-112
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    • 1987
  • The purpose of this study is to investigate the influence of addition of sodium dodecyl sulfate(SDS) when wool is treated with sodium hydroxide(NaOH). Physical and chemical changes were examined on wool treated with various cone. of NaOH and SDS simultaneously. The result are as follows. 1. The higher the temperature and the longer the time of NaOH treatment are, the more alkali damage wool get : increase in weight loss and decrease in urea-bisalphite solubility and in tensile strength. But the treatment time reacts less effective than the temperature. 2. When wool is treated with NaOH, at NaOH cone. under $10^{-3}M$., the addition of SDS alleviates the alkali reaction on wool: increase in cystine contents and in urea-bisulpite solubility, and decrease in degree of swelling. On the other hand, at NaOH cone. over $10^{-2}M$., the addition of SDS promotes the alkali reaction on the wool. 3. When wool is treated with NaOH, the addition of SDS shows no changes on the tensile strength. On the other hand, at NaOH cone. under $10^{-2}M$., the addition of SDS shows no changes on the softness of wool, but at the $10^{-1}M$. NaOH cone. addition of SDS increases the soft-ness of wool. The area shrinkage of wool treated with NaOH and SDS shows less changes than with NaOH only.

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Ultimate strength performance of tankers associated with industry corrosion addition practices

  • Kim, Do Kyun;Kim, Han Byul;Zhang, Xiaoming;Li, Chen Guang;Paik, Jeom Kee
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제6권3호
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    • pp.507-528
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    • 2014
  • In the ship and offshore structure design, age-related problems such as corrosion damage, local denting, and fatigue damage are important factors to be considered in building a reliable structure as they have a significant influence on the residual structural capacity. In shipping, corrosion addition methods are widely adopted in structural design to prevent structural capacity degradation. The present study focuses on the historical trend of corrosion addition rules for ship structural design and investigates their effects on the ultimate strength performance such as hull girder and stiffened panel of double hull oil tankers. Three types of rules based on corrosion addition models, namely historic corrosion rules (pre-CSR), Common Structural Rules (CSR), and harmonised Common Structural Rules (CSR-H) are considered and compared with two other corrosion models namely UGS model, suggested by the Union of Greek Shipowners (UGS), and Time-Dependent Corrosion Wastage Model (TDCWM). To identify the general trend in the effects of corrosion damage on the ultimate longitudinal strength performance, the corrosion addition rules are applied to four representative sizes of double hull oil tankers namely Panamax, Aframax, Suezmax, and VLCC. The results are helpful in understanding the trend of corrosion additions for tanker structures.

근용 안경을 최초 장용하는 노안에 대한 임상적 연구 (A Clinical Study on Presbyopia in Wearing the Near Spectacle for the First Time)

  • 유종숙;임현선;이수천;황정희;김효정
    • 한국안광학회지
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    • 제13권4호
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    • pp.103-107
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    • 2008
  • 목적: 본 연구는 처음 근용 안경을 착용하고자 하는 노안을 대상으로 근용 가입도 검사를 하여 가입도와 나이, 성별, 직업군, 구면 도수, 난시 도수와의 상관관계를 평가하고자 하였다. 방법: 155명의 피검사자의 좌, 우안(310안)을 대상으로 비조절마비 자각적 굴절 검사 및 크로스 실린더를 이용한 근용 가입도 검사를 하였다. 결과: 최초 근용 가입도는 +0.75D에서 +1.75D까지 검사되었고, 43세 이전의 평균 가입도는 +1.06D, 44세~46세까지는 +1.08D, 47세~49세까지는 +1.23D, 50세 이상에서는 +1.46D이었다. 피검사자의 평균 연령은 47.6세, 남자 74명, 여자 81명이었고 근거리 직업군이 71명, 원거리 직업군이 83명이었다. 결론: 가입도는 나이, 직업군, 난시 도수와 높은 상관성을 나타내었다(p<0.05, p<0.05, p<0.05).

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막걸리 사워도우로 제조한 식빵의 품질특성 (Quality Characteristics of White Bread Made with Makgeolli Sourdough)

  • 유병성;윤춘식;김현아;장윤희
    • 한국식품조리과학회지
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    • 제33권1호
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    • pp.94-103
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    • 2017
  • Purpose: This study developed sourdough bread according to consumers' preferencesby shortening the sourdough fermentation process time through addition of makgeolli to sourdough. Methods: Fermentation time was measured by adding makgeolli and water to wheat flour. Results: Fermentation time was shorter than that of starter made with only water and flour, with 5 hours of primary fermentation and 3 hours of secondary fermentation. The optimum mixing ratio was 400 g of flour, 192 mL of water, and 48 mL of makgeolli. An increase in makgeolli sourdough content decreased crude protein and moisture contents of white bread. Crude fat and ash contents increased, and volume of bread was decreased as sourdough increased. The height of bread prepared with makgeolli sourdough was lower than that of bread without makgeolli sourdough. According to the results of the texture measurement, hardness, gumminess, and chewiness of sourdough group were lower as the addition of sourdough increased. Addition of makgeolli sourdough to white bread resulted in decreased lightness, but increased yellowness of white bread. Preparation of white bread with addition of sourdough improved taste and flavor compared to bread prepared only with wheat flour. Conclusion: The highest sensory preference was observed for white bread prepared whit 5 g of sourdough.

Distribution of Inter-Contact Time: An Analysis-Based on Social Relationships

  • Wei, Kaimin;Duan, Renyong;Shi, Guangzhou;Xu, Ke
    • Journal of Communications and Networks
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    • 제15권5호
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    • pp.504-513
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    • 2013
  • Communication in delay tolerant networks (DTNs) relies on message transport by mobile nodes, and a correct understanding of the node mobility characteristics is therefore crucial to the design of an efficient DTN routing protocol. However, previous work has mainly focused on uncovering all behaviors of node movement, which is not conducive to accurately detecting the specific movement characteristics of a different node. In this paper, we seek to address this problem based on a consideration of social relationships. We first consider social ties from both static and dynamic perspectives. For a static perspective, in addition to certain accidental events, social relations are considered for a long time granularity and tend to be stable over time. For a dynamic perspective, social relations are analyzed in a relatively short time granularity and are likely to change over time. Based on these perspectives, we adopted different efficient approaches to dividing node pairs into two classes, i.e., familiar and unfamiliar pairs. A threshold approach is used for static social ties whereas a density-based aggregation method is used for dynamic social relationships. Extensive experimental results show that both familiar and unfamiliar node pairs have the same inter-contact time distribution, which closely follows a power-law decay up to a certain point, beyond which it begins to exponentially decay. The results also demonstrate that the inter-contact time distribution of familiar pairs decays faster than that of unfamiliar pairs, whether from a static or dynamic perspective. In addition, we also analyze the reason for the difference between the inter-contact time distributions of both unfamiliar and familiar pairs.

2차로도로 평균 통행속도-총지체율-교통량 관계 곡선 재정립 (Relationships Between Average Travel Speed, Time-Delayed Rate, and Volume on Two-lane Highways with Simulation Data)

  • 문재필;김용석
    • 한국도로학회논문집
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    • 제14권6호
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    • pp.131-138
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    • 2012
  • PURPOSES : Two-lane highways have one lane in each direction, and lane changing and passing maneuvers take place in the opposing lane depending on the availability of passing sight distance. 2001 Korea Highway Capacity Manual (KHCM) is classified into two classes of two-lane highways (Type I, II), and average travel speed and time-delayed rate are used as measures of effectiveness (MOEs). However, since existing two-lane highways have both uninterrupted and interrupted traffic flow-system elements, a variety of free-flow speeds exhibits in two-lane highways. In addition, it is necessary to check if the linear-relationship between volumes and time-delayed rate is appropriate. Then, this study is to reestablish the relationship between average travel speed, time-delayed rate, and flow. METHODS : TWOPAS model was selected to conduct this study, and the free-flow speeds of passenger cars and the percentage of following vehicles observed in two-lane highways were applied to the model as the input. The revised relationships were developed from the computer simulation. RESULTS : In the revised average travel speed vs. flow relationship, the free-flow speed of 90km/h and 70km/h were added. It shows that the relationship between time delayed-rate and flow appeared to be appropriate with the log-function form and that there was no difference in time-delayed rate between the free flow speeds. In addition to revise the relationships, the speed prediction model and the time-delayed rate prediction model were also developed. CONCLUSIONS : The revised relationships between average travel speed, time-delayed rate, and flow would be useful in estimating the Level of Service(LOS) of a two-lane highway.

아스코르브산과 시스테인이 밀가루의 리올로지 성질과 노-타임 반죽법에 미치는 영향 (Effects of Ascorbic Acid and L-Cysteine on Rheological Properties of Wheat Flour and on No-time Dough Process)

  • 조남지;허덕균;김성곤
    • 한국식품과학회지
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    • 제21권6호
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    • pp.800-807
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    • 1989
  • 아스코르브산을 산화제로 한 노-타임 제빵법에 대하여 연구하였다. 시스테인은 파리노그라프의 흡수율을 증가시켰으나, 안정도와 반죽시간은 감소시켰다. 반죽의 신장성도 시스테인에 의하여 증가하였다. 동일한 시스테인 함량에서 아스코르브산을 1.5배 첨가한 경우 파리노그라프의 흡수율을 감소하였으나 안정도와 반죽시간은 변하지 않았다. 또한 반죽의 신장성은 아스코르브산에 의하여 감소하였다. 아스코르브산은 제방 흡수율과 반죽시간에 영향을 주지 않았고, 제빵의 최적농도는 시스테인 40ppm, 아스코르브산 100ppm이었다.

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