• Title/Summary/Keyword: jam

Search Result 515, Processing Time 0.025 seconds

Relative Efficiency of Korea Trucking Transport Business Using DEA Model (DEA를 이용한 국내 화물자동차 운송업의 상대적 효율성분석)

  • Chang, Myung-Hee
    • The Journal of the Korea Contents Association
    • /
    • v.10 no.12
    • /
    • pp.328-341
    • /
    • 2010
  • Korea Trucking Transport Business is one of principal national logistics sector, though, so many issues and problems came to arises, which brought cargo transport system crisis over the country such as logistics enormous jam and traffic. This paper analyzes the efficiency of korean trucking transport business firms using DEA model. We evaluate the CCR, BCC efficiency and RTS of 30 trucking transport firms. We also suggest the trucking transport firms which can be benchmarked based on analyzed information. The result shows that seven enterprises whose values of CCR efficiency are 1, and fifteen enterprises whose values of BCC efficiency are 1. RTS indicates IRS of 16 firms, DRS of 5 firms and CRS of 9 firms.

Liquidity Evaluation on the Horizontal Branch Pipe Connected to a Food Waste Disposer (디스포저에 의한 음식물류폐기물 횡지관 유동성 평가)

  • Jang, Choon-Man;Lee, Sang-Moon;Kim, Chul-Kyu;Park, Se-Joon;Yu, Jong-Chan
    • The KSFM Journal of Fluid Machinery
    • /
    • v.20 no.1
    • /
    • pp.53-58
    • /
    • 2017
  • This paper describes liquidity evaluation on the horizontal branch pipe connected to a food waste disposer and performance of five disposers marketed. Experimental apparatus for analyzing the five disposers has been introduced to measure vibration, sound level and power consumption of the disposers. Simulator for analyzing the required water velocity to avoid waste jam inside the pipe connected to a food waste disposer has been designed and constructed. The simulator can control some experimental parameters: pipe slope, disposer supply water quantity, food waste materials and operation time of a disposer. Throughout the experimental measurements of the disposers marketed, it is found that the time need to crash food waste is about 20 seconds on the average. At the same flow condition, increase rate of internal water velocity is accelerated as the pipe slope increases. The water velocity inside the pipe having 50 A and slope of 1/50 is 0.26 m/s when the water flowrate to supply the disposer is 16 l pm. Considering the specific gravity and adhesion property of food waste, water velocity of the horizontal branch pipe connected to a food waste disposer need to excess 0.26 m/s at least to avoid the waste blockage inside the pipe.

Content Differences of Pb and Cd by Trophic Levels of the Ecosystem near Highways with Different Traffic Volumes (교통량이 다른 고속도로변 생태계의 영양단계별 납과 카드뮴 함량의 차이)

  • Chung, Wan-Ho;Hai-Poong Lee
    • The Korean Journal of Ecology
    • /
    • v.10 no.1
    • /
    • pp.7-16
    • /
    • 1987
  • The content of Pb and Cd in the soil, producer, 1st consumer and 2nd consumer by the distance from two highway with different construction years and traffic volumes was measured from 1984 through 1986. The result was compared with that of a control in Yangsu-ri near Mt. Unak, Namyangju-gun, Kyunggi-do. The producers in the area of Yangjae-done are composed of 27 species of floras with Glycine soja being the dominant species while those in Shingal 20 species, with Leesia japonica being the dominant species. The faunas in the former area include 37 families and 69 species, with insects being dominant. In the area of Yangjae-dong, the biomass by trophic levels increased from the ration of 1/400 between producer and 1st consumer to the ratio of 1/10 between 1st consumer and 2nd consumer. The Pb content of soil, producer, 1st consumer and 2nd consumer in Yangjae-done near the Kyungbu highway with traffic jam has the sigingacant difference of 1% level at the vicinity of 10 meters and it is the same with that of Shingal area nearthe Youngdong highway with relatively sparse traffic except for the 2nd consumer. In case of cadmium content, the 1st and 2nd consumer has 1% signigicant difference near the Kyungbu highway and other trophic levels have no diference. Besides, the content of Pb and Cd at the site 1, 2 and 3 within the range of 100 meters from the two highways has 1% significant difference from that of a control while the site 4 has no difference.

  • PDF

A Historical Study of Textiles - With an Emphasis on Korean Cotton Fabrics - (직물(織物)의 역사적(歷史的) 고찰(考察) - 우리나라의 선직물(線織物)을 중심(中心)으로 -)

  • Lee, Soon-Hong
    • Journal of the Korean Society of Costume
    • /
    • v.5
    • /
    • pp.65-81
    • /
    • 1981
  • I referred to documents to study the origin and the progressing process of textiles. Cotton seeds were first imported from China by Mun, Ik Jem at the end of the era of Koryeo, and cotton had several different names such as mok-myen, cho-myen, gil-pae, baek-chep-za, tap-po, ban-ki-wha, dong-yep-po and so on. Since the era of the Three Kingdoms, people had heard of cloth of superior quality but it was not certain whether it was imported from China or made in our country. It seems that cotton was not made during that period, white silk, hemp cloth, and ramie fabric were produced. At that time, linen was called cotton by mistake. After importing cotton seeds from China, all the people began to plant them and made their clothes from them. At the beginning of the Yi Dynasty, the weaving technique was dependent on China. However, the government persuaded farmers to plant them. At that time cotton was used as a means of purchasing instead of money. Silkworms raising started during the era of the Three Kingdoms and it was widely spread at the beginning of the Yi Dynasty. In order to encourage sericulture' spinning and weaving instruments were installed in the royal palace and the queen with sher court maids demonstrated how to spin and weave. The activity was named "chin-jam-ye." Linen was the representative of all textiles and it was also very popular. The technique of weaving had already been highly developed at the era of Silla. During the era of the Three Kingdoms people used "bang-chu-cha" as a weaving instrument. They discovered several new hand machines in the period of the Yi Dynasty: they were instrument of removing seeds, spinning wheel, hemp cloth loom and so on, and we find the remains of them these days.

  • PDF

A Simulation of Vehicle Parking Distribution System for Local Cultural Festival with Queuing Theory and Q-Learning Algorithm (대기행렬이론과 Q-러닝 알고리즘을 적용한 지역문화축제 진입차량 주차분산 시뮬레이션 시스템)

  • Cho, Youngho;Seo, Yeong Geon;Jeong, Dae-Yul
    • The Journal of Information Systems
    • /
    • v.29 no.2
    • /
    • pp.131-147
    • /
    • 2020
  • Purpose The purpose of this study is to develop intelligent vehicle parking distribution system based on LoRa network at the circumstance of traffic congestion during cultural festival in a local city. This paper proposes a parking dispatch and distribution system using a Q-learning algorithm to rapidly disperse traffics that increases suddenly because of in-bound traffics from the outside of a city in the real-time base as well as to increase parking probability in a parking lot which is widely located in a city. Design/methodology/approach The system get information on realtime-base from the sensor network of IoT (LoRa network). It will contribute to solve the sudden increase in traffic and parking bottlenecks during local cultural festival. We applied the simulation system with Queuing model to the Yudeung Festival in Jinju, Korea. We proposed a Q-learning algorithm that could change the learning policy by setting the acceptability value of each parking lot as a threshold from the Jinju highway IC (Interchange) to the 7 parking lots. LoRa Network platform supports to browse parking resource information to each vehicle in realtime. The system updates Q-table periodically using Q-learning algorithm as soon as get information from parking lots. The Queuing Theory with Poisson arrival distribution is used to get probability distribution function. The Dijkstra algorithm is used to find the shortest distance. Findings This paper suggest a simulation test to verify the efficiency of Q-learning algorithm at the circumstance of high traffic jam in a city during local festival. As a result of the simulation, the proposed algorithm performed well even when each parking lot was somewhat saturated. When an intelligent learning system such as an O-learning algorithm is applied, it is possible to more effectively distribute the vehicle to a lot with a high parking probability when the vehicle inflow from the outside rapidly increases at a specific time, such as a local city cultural festival.

A Study on Active Priority Control Strategy for Traffic Signal Progression of Tram (트램의 연속통행을 위한 능동식 우선신호 전략 연구)

  • Lee, In-Kyu;Kim, Young-Chan
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.13 no.3
    • /
    • pp.25-37
    • /
    • 2014
  • Recently, our local governments are conducting the introduction of tram system because it is recognized as an effective public transit that can solve a traffic jam in downtown, decreasing public transit share and environmental issues in world wide cities. We developed the Active Priority Control Strategy to efficiently operate a tram in our existing traffic signal system. This study organized the tram system for operating the Active Priority Signal Control, developed the algorithm that calculates a tram-stop dwell time in order to pass the downstream intersection without a stop. The dwell time is determined by arrival time at tram-stop, downstream signal time, and the location of a opposite tram, it can be reduced by choosing the optimal one among Signal Priority Controls. Using the VISSIM and VISVAP model, we conducted a simulation test for the city of Chang-won that it is expected to install a tram system. It showed that a developed signal control strategy is effective to prevent a tram's stop in intersections, to reduce a tram's travel time.

Benefit Analysis of Carpool Service in Public Agencies Transferring Innovation Cities (혁신도시이전 공공기관의 카풀 도입 편익분석)

  • Do, Myung sik;Jung, Ho yong
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.16 no.6
    • /
    • pp.169-181
    • /
    • 2017
  • As vehicle supply rate increases, traffic jam-related problems emerge and sharing transportation including carpool, centered on the advanced countries, becomes a major interest. This study aims to analyze benefit generated by carpool during the rush hours of medium and long distance travel, focused on the workers of public Agencies relocated to innovation cities. In order to compute benefit, carpool demand of relocated public Agencies was estimated and travel speed was estimated according to reduced traffic volume through carpool adoption using a traffic flow model. The benefit were computed dividing them into direct benefit and indirect benefit. As a result, 23billion KRW and 56.5billion KRW were annually revealed to be generated in terms of direct benefit and indirect benefit. The study result is expected to be used as part of basic research to adopt carpool for future traffic demand management.

Effect of wettability of gypsum materials and rubber impression material on the marginal fitness of zirconia copings (석고 모형재와 고무인상재의 젖음성이 지르코니아 코핑의 변연적합도에 미치는 영향)

  • Kim, Won-Young;Chung, In-Sung;Jeon, Byung-Wook
    • Journal of Technologic Dentistry
    • /
    • v.38 no.4
    • /
    • pp.255-262
    • /
    • 2016
  • Purpose: This study examined the effect of wettability of gypsum materials and rubber impression material on the marginal fitness of zirconia copings. Methods: Three commercially available gypsum materials(Fugirock EP, Snow Rock, Tuff Rock) and three zirconia blocks(iJAM Emerald, LUXEN Smile block, ICE Zirkon transluzent) were studied. The zirconia copings were fabricated by using dental CAD/CAM system. Contact angles on the impression materials were measured with contact angle measuring device. Silicone replica method was used to measure the marginal fitness and cutting was performed on the bucco-lingual and mesio-distal sides. It were observed with a stereomicroscope at °ø40 magnification. The data were statistically analyzed with One-way ANOVA. Results: Mean values of contact angles were $58.3{\pm}0.7^{\circ}$ for Tuff Rock, $77.5{\pm}0.5^{\circ}$ for Fugirock EP and $87.8{\pm}0.5^{\circ}$ for Snow Rock and the difference between them was statistically significant(p<0.05). The smallest values of marginal fitness for the JF groups were $30.7{\pm}3.0{\mu}m$ for bucco-lingual direction, $29.3{\pm}3.0{\mu}m$ for mesio-distal direction. One-way ANOVA showed statistically significant difference between groups for marginal fitness(p<0.05). Conclusion: Tuff rock gypsum material had superior wettability to others. The mean marginal fitness of the Tuff rock gypsum material group were significantly better than other groups. Thus they can be also expected to show clinically satisfactory marginal fitness.

Research of Controled Traffic Signal by Image Processing and Fuzzy Logic (영상처리 및 퍼지논리를 이용한 교통 신호제어 연구)

  • Shin, Ji-Hwan;Park, Mu-Hun
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
    • /
    • v.9 no.1
    • /
    • pp.100-108
    • /
    • 2016
  • In this paper, We propose a method which prevents severe traffic jam by controlling traffic signal by itself based on image-processed information and fuzzy logic. The detailed idea of this method is first to let a closed monitoring camera gather the number of cars which show the flow of traffic the designated roads which are commonly considered to have traffic. After executing the image processing method on each image gathered from the monitoring camera, this system determines the changing timing of traffic signal based on fuzzy logic. Also, this image processing method shows good performance in real road environment because the setup background image which used in this system is designed to be updated in real time. All of good points mentioned above would lead driver and users to cost efficient and time efficient results by preventing the increase of the number of traffic on road in advance with the automatic traffic signal controlling algorithm based on the fuzzy logic.

A Case Study of Chair at Railroad Vehicle (철도차량의 의자에 관한 비교연구)

  • Lee, Sae Hwan
    • Journal of the Korea Furniture Society
    • /
    • v.23 no.4
    • /
    • pp.467-478
    • /
    • 2012
  • Interurban railway is expanded by transportation that population can be centralism and cope efficiently in traffic jam by augmentation of vehicles in the city. Railroad chair departs in space of an existent simple rest and products that can raise human body standard and size by powerful engineering vicinity, quality of the material, psychological satisfaction etc. of users are developed steadily. Specially, study of space that can use various materials efficiently with bodily size government official because various of man and woman old and the young etc.. are using in occasion of the train is urgently required. Specially, railroad chair is a product that material and standard, structure, human body engineering, a finish etc. is studied variously. In the case of advanced nation, in case of design a chair operating time of railroad, is placed as all standards orderly and harmonious because is considered exercise dynamics etc.. and designs. The other side, in the case of our country, study expert of chair is short real and is depending on technological data of overseas railway vehicle. Chair for railroad must consider removal of short-range, long distance. That have to be consider to a lot of uncomfortable such as psychological satisfaction of user because the domestic Motor Companies are defining in fair development study and many researchers but the railroad chair company are not accumulated professional manpower and technological know-how. Railway vehicle can recognize that overseas visitors as well as native is important element as space that space is exposed internationally by product that Public personality which used cultural value is strong. Therefore, wish to plan valid spec relationship presentation of various design and specification, function etc.. and contribute to railroad chair development design process lists and analyzes van instances of railway vehicle chair of inside and outside of the country through this study.

  • PDF