• 제목/요약/키워드: Express Service

검색결과 338건 처리시간 0.029초

A Genetic Algorithm Based Approach to the Profitable Tour Problem with Pick-up and Delivery

  • Lee, Hae-Kyeong;Ferdinand, Friska Natalia;Kim, Tai-Oun;Ko, Chang-Seong
    • Industrial Engineering and Management Systems
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    • 제9권2호
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    • pp.80-87
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    • 2010
  • As express courier market expands rapidly, companies are exposed to fierce competition. To cope with struggle for their survival, they are continuously making efforts to improve their service system. Even if most of service centers are directly linked to a consolidation terminal in courier service network, some of them with regional disadvantages are operated in milk run type from/to the consolidation terminal, which is a traditional PDP (Pick-up and Delivery Problem). This study suggests an approach to solve the PDP with the objective of maximizing the incremental profit, which belongs to PTP (Profitable Tour Problem) class. After the PTP is converted to TSP (Traveling Salesman Problem) with the same objective, a heuristic algorithm based on GA (Genetic Algorithm) is developed and examined through an example problem in practice of a courier service company in Korea.

SSD 입출력 요청 스트림들의 QoS 지원을 위한 플래시 연산 그룹 스케줄링 (Flash Operation Group Scheduling for Supporting QoS of SSD I/O Request Streams)

  • 이은규;원선;이준우;김강희;남이현
    • 정보과학회 논문지
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    • 제42권12호
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    • pp.1480-1485
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    • 2015
  • 최근에 서버 시스템에서 SSD(Solid-State Drive)가 고성능 저장장치 및 캐시로서 많이 사용됨에 따라 다양한 서버 응용들의 입출력 요청 스트림들을 위해 SSD 수준에서 서비스 품질(Quality-of-Service)를 제공할 수 있는지에 대한 관심이 높아지고 있다. 현재까지 대부분의 SSD는 SATA 버스 상에서 AHCI 컨트롤러를 사용해왔기 때문에 각 입출력 스트림을 SSD 내부에서 구별하여 서비스할 수가 없었다. 그러나, 최근에 새로운 SSD 인터페이스로서 PCI Express 버스 상에서 NVME 컨트롤러가 제안됨에 따라 각 입출력 스트림을 SSD 내부에서 구별할 수 있게 되었고, 이에 따라 입출력 요청들을 스케줄링 할 수 있게 되었다. 본 논문은 NVME 기반 플래시 저장 장치를 위한 플래시 연산 그룹 스케줄링(Flash Operation Group Scheduling)을 제안하고, 가중치에 따라 입출력 스트림별로 비례 지분 대역폭을 제공할 수 있음을 QEMU 기반 시뮬레이션을 통해 보인다.

Research on the Relationship Between Social Capital and Enterprise Performance in Supply Chain Environment

  • Li, Jian;Lee, Sang-Chun;Jeong, Ha-Eun
    • Journal of Korea Trade
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    • 제24권4호
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    • pp.34-48
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    • 2020
  • Purpose - The rapid rise of e-commerce enterprises has led to the development of the logistics industry. At the same time, some enterprises are motivated by the interests to start reducing costs and inputs, which on the contrary leads to low quality of service, thus reducing customer satisfaction. In recent years, vicious competition, violent express delivery and lack of professionalism in the logistics market have led to high annual customer complaint rate, which has resulted in the company losing many loyal customers, but also unable to obtain new customers. Therefore, to pay attention to and understand the psychological needs of customers and improve the quality of logistics distribution service has become a pressing problem for Every express company. Design/methodology - By analyzing the problems existing in logistics distribution of express companies, this paper explores various factors affecting customer satisfaction and takes consumer sentiment as a mediating variable. Through questionnaires to collect relevant data, put forward hypotheses for empirical analysis, use two different software including SPSS 21.0 and AMOS 21.0 to analyze the information, draw conclusions and make recommendations. Findings - According to the above research results, the reliability, convenience, efficiency, professional can have a positive impact on customer satisfaction through the mediating effect of their sentiment, convenience and professional on consumer sentiment and satisfaction are more significant. Originality/value - This paper the establishment of distribution service indicators related to customer satisfaction and empirical analysis can not only enrich and supplement the distribution service quality indicator system studied by the former, but also provide a theoretical basis for future research.

철도수송수요를 고려한 정차역 선정과 열차운행방안 -경부선 서울~조치원구간을 중심으로- (A primary study of Rail Station Selection and Train Operation Management Plan with Transportation Demand)

  • 문대섭;정병현
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2001년도 춘계학술대회 논문집
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    • pp.80-87
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    • 2001
  • The purposes of this primary study are the selection of rail station and train operation management techniques for express-rail operation service at the convectional railway electrification. For these analyses, we used the KNR statistics and KROIS data of rail stations and train users by rail line. Therefore, we chose the important stations for express-rail operation of Kyongbu conventional rail line (esp. Seoul-Jochiwon section) through the rail transportation demand. and then, suggested primary operational management plan thorough the effects analyses of decreasing total travel time and increasing transportation demand by train speed-up. This study has some bounds and limits for proceeding, as it does, we excluded as followings: the conditionals of fate system, headways and train diagram, economic/financial analysis and technological assessment, and other railway technological infrastructures and a certain railcar specification, etc. . We propose to enlarge this study into a feasibility study of express or skip-stop operation service and compatible vehicle system decision considering with the best possible investment rail line, furthermore. in front of Kyongbu (Seoul-Busan) high-speed rail open in 2004, we have to try to progress the efficiencies of railway operation applying various train operation management plan.

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컴퓨터 시뮬레이션에 의한 이용객의 교통에 관한 연구 (Computer simulation of passenger flow)

  • 차균현
    • 전기의세계
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    • 제27권1호
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    • pp.35-44
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    • 1978
  • In this paper the best way of servicing to the waiting guests at the Express Bus Terminal, is to determined by the computer simulation. The mathematical model for the waiting guests is formulated with the statistics data by researching the waiting lines of the guests at the guests at the specified Express Bus Terminal. The waiting phenomena is simulated using Monte Carlo method to decide the proper number of window and the time for servicing. Finally it present the way of the improvement of service with the good results of simulation.

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유비쿼터스 환경에서 센서 데이터와 서비스의 연계를 표현하는 마크업 언어 (A Markup Language for Describing the Linkage between Sensor Data and Service in the Ubiquitous Environment)

  • 이훈순;진성일
    • 정보처리학회논문지D
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    • 제15D권2호
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    • pp.247-256
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    • 2008
  • 유비쿼터스 시대에는 우리 주변에 산재하는 수많은 스마트 객체들이 끊임없이 방대한 양의 센서 데이터를 생성해 낸다. 인터넷이 널리 보급됨에 따라 인터넷으로 연결된 정보의 바다로부터 유용한 정보를 찾는데 도움을 주는 인터넷 정보 검색 엔진이 등장한 것처럼, 스마트 객체가 생성한 센서 데이터로부터 우리 삶을 윤택하게 하는데 활용될 정보를 추출하여 응용 서비스에 전달하는 일을 함으로써 유비쿼터스 서비스를 개발하는데 도움을 주는 센서 데이터 스트림 처리 미들웨어들이 등장하고 있다. 이러한 센서 데이터 스트림 처리 미들웨어를 이용하여 유비쿼터스 서비스를 사람들에게 제공하기 위해서는 제공될 서비스와 관련된 정보를 미들웨어에게 알려 주어야 한다. 이에 본 논문에서는 센서 데이터를 이용하는 유비쿼터스 서비스를 나타내는데 필요한 정보를 구분하고, 이를 효과적으로 표현하는 컨텍스트 드리븐 서비스 마크업 언어를 제안한다. 제안하는 컨텍스트 드리븐 서비스 마크업 언어를 이용하면 다양한 상황에서 제공되어야 하는 다양한 유비쿼터스 서비스를 쉽게 표현할 수 있다.

기존선 고속화 차량의 틸팅시스템 개념설계 연구 (The Concept design of Tilting system for Express tilting train for contentional line)

  • 김남포;유원희;최성규
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2002년도 춘계학술대회 논문집
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    • pp.351-358
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    • 2002
  • Tilting system allow the train to pass curve at higher speed without affecting passenger comfort. As the tilting trains offer the optimum means of providing faster and more comportable rail service with minimum of environmental disturbance and capital investment, more than 14 countries have now adopted or are about to adopt tilting train technology. The Korean National Railroad is also planing to apply faster tilting train to the areas where the High speed rail service are not provided. This paper shows the concept design of Bogie and Tilting system for 180 km/h Express tilting train for Korean conventional line, which was done as a part of the KNR's R&D project.

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공간효과분석을 이용한 건강보험 환자 관외 의료이용도와 관련된 요소분석 (Analysis on Factors Relating to External Medical Service Use of Health Insurance Patients Using Spatial Regression Analysis)

  • 노윤호
    • 보건행정학회지
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    • 제23권4호
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    • pp.387-396
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    • 2013
  • Background: The purpose of this study was to analyze the association between areas of Korea Train Express (KTX) region and external medical service use in Korean society using spatial statistical model. Methods: The data which was used in this study was extracted from 2011 regional health care utilization statistics and health insurance key statistics from National Health Insurance Corporation. A total spatial units of 229 districts (si-gun-gu) were included in this study and spatial area was all parts of the country excepted Jeju, Ulleungdo island. We conducted Kruskal-Wallis test, correlation, Moran's I and hot-spot analysis. And after, ordinary linear regression, spatial lag, spatial error analysis was performed in order to find factors which were associated with external medical service use. The data was processed by SAS ver. 9.1 and Geoda095i (windows). Results: Moran's I of health insurance patients' external medical service use was 0.644. Also, population density, Seoul region, doctor factors positively associated with health insurance patients' external medical service. In contrast, average age, health care organization per 100 thousand were negatively associated with health insurance patients' external medical service use. Conclusion: The finding of this study suggested that health insurance patient's external medical service use correlated for seoul region in korea. The study results imply the need for more attention medical needs in the region (si-gun-gu unit) for health insurance patients of seoul region. It is important to adapt strategy to activation of primary health care as well as enhancing public health institution for prevent leakage of patients to other areas.