• Title/Summary/Keyword: combined service

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콘크리트 구조물의 수명예측을 위한 모델 분석 및 평가에 관한 연구 (I) (Evaluation of Service Life Prediction Models for Concrete Structure (I))

  • 김도겸;이종석;이장화;송영철;조명석
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1998년도 가을 학술발표대회 논문집(III)
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    • pp.731-736
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    • 1998
  • Deteriorations of concrete are governed by combined factors such as environmental stressors, processes and rates of deteriorations. Due to this reason, it's very difficult and important issue to predict quantitatively the service life of concrete structure. From this pont of views, the purpose of this study is to propose the approaches on the further development for predicting the remaining service life of concrete by analyzing the deteriorations mechanism and evaluating the existing models.

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Performance Analysis of REDP Marker with a combined Dropper for improving TCP Fairness of Assured Services

  • Kyeong Hur;Lee, Yeonwoo;Cho, Choon-Gen;Park, Hyung-Kun;Eom, Doo-Seop;Tchah, Kyun-Hyon
    • 한국통신학회논문지
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    • 제29권7B호
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    • pp.711-721
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    • 2004
  • To provide the end-to-end service differentiation for assured services, the random early demotion and promotion (REDP) marker in the edge router at each domain boundary monitors the aggregate flow of the incoming in-profile packets and demotes in-profile packets or promotes the previously demoted in-profile packets at the aggregate flow level according to the negotiated interdomain service level agreement (SLA). The REDP marker achieves UDP fairness in demoting and promoting packets through random and early marking decisions on packets. But, TCP fairness of the REDP marker is not obvious as fur UDP sources. In this paper, to improve TCP fairness of the REDP marker, we combine a dropper with the REDP marker. To make packet transmission rates of TCP flows more fair, at the aggregate flow level the combined dropper drops incoming excessive in-profile packets randomly with a constant probability when the token level in the leaky bucket stays In demotion region without incoming demoted in-profile packets. It performs a dropping in the demotion at a domain boundary only if there is no prior demotion. The concatenate dropping at multiple domains is avoided to manifest the effect of a dropping at a domain boundary on TCP fairness. We experiment with the REDP marker with the combined dropper using ns2 simulator for TCP sources. The simulation results show that the REDP marker with the combined dropper improves TCP fairness in demoting and promoting packets by generating fair demoted in-profile traffic compared to the REDP marker. The effectiveness of the selected drop probability is also investigated with showing its impact on the performance of the REDP marker with the combined dropper.

외식사업학과 교과과정 개발에 관한 연구 (The Development of Curriculum on Department of Food Service Business)

  • 김두진;채기수
    • 한국식품영양학회지
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    • 제9권3호
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    • pp.281-288
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    • 1996
  • The purpose of this study was to develop the curriculum for the Department of Food Service Business in Junior College. The purpose of the curriculum development is to train professionals combined theory and practice for medium or small restaurant managers. We have developed a model curriculum, which was based on Job analyses for related business, analyses of the curricula of departments related with food service, and survey on the questionnaire. The subjects of the model curriculum are as follows. 1) Subjects related with Food and Food Sanitation, 2) Subjects related nth Cuisine, 3) Subjects related with Restaurant Management and Service, 4) Subjects related nth training In practical business, and 5) Subjects related with a foreign language. The effects on opening the Department of Food Service are as follows. 1) To train professionals (or food service business, 2) Activation of the study on Food Service Industry, 3) Establishment of the traditional food culture, 4) Activation of the Tourist Industry, and 5) To improve the Quality of restaurant employees.

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Combined Service Subscription and Delivery Energy-Efficient Scheduling in Mobile Cloud Computing

  • Liu, Xing;Yuan, Chaowei;Peng, Enda;Yang, Zhen
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권5호
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    • pp.1587-1605
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    • 2015
  • Mobile cloud computing (MCC) combines mobile Internet and cloud computing to improve the performance of applications. In MCC, the data processing and storage for mobile devices (MDs) is provided on the remote cloud. However, MCC faces the problem of energy efficiency caused by randomly varying channels. In this paper, by introducing the Lyapunov optimization method, we propose a combined service subscription and delivery (CSSD) algorithm that can guide the users to subscribe to services reasonably. This algorithm can also determine whether to deliver the data and to whom data is sent in the current time unit based on the queue backlog and the channel state. Numerical results validate the correctness and effectiveness of our proposed CSSD algorithm.

서비스 위치 그룹핑을 위한 보로노이 다이어그램 기반의 유전자알고리듬 (Regrouping Service Sites: a Genetic Approach using a Voronoi Diagram)

  • 서정연;박상민;정인재;김덕수
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회/대한산업공학회 2005년도 춘계공동학술대회 발표논문
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    • pp.179-187
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    • 2005
  • In this paper, we consider the problem of regrouping a number of service sites into a smaller number of service sites called centers. Each service site is represented as a point in the plane and has an associated value of service demand. We aim to group the sites so that each group has the balanced service demand and the sum of distances from the sites in the group to their corresponding center is minimized. To solve this problem, we propose a hybrid genetic algorithm that is combined with Voronoi diagrams. We provide a variety of experimental results by changing the weights of the two factors: service demands and distances. Our hybrid algorithm finds better solutions in a shorter computation time in comparison with a pure genetic algorithm.

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입지선정 및 차량경로문제 (A Combined Location and Vehicle Routing Problem)

  • 강인선
    • 산업경영시스템학회지
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    • 제19권37호
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    • pp.263-269
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    • 1996
  • The cost and customer service level of a logistics system depend primarily on the system design of the physical supply system and physical distribution system. The study presents the mathematical model and a huristic solution method of a combined location - vehicle routing problem(LVRP). In LVRP the objective is to determine the number and location of the distribution centers, the allocation of customers to distribution centers, and the vehicle delivery routes, so as to minimize the logistics total cost and satisfy the customer.

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Concrete structures under combined mechanical and environmental actions: Modelling of durability and reliability

  • Vorechovska, Dita;Somodikova, Martina;Podrouzek, Jan;Lehky, David;Teply, Bretislav
    • Computers and Concrete
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    • 제20권1호
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    • pp.99-110
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    • 2017
  • Service life assessments which do not include the synergy between mechanical and environmental loading are neglecting a factor that can have a significant impact on structural safety and durability assessment. The degradation of concrete structure is a result of the combined effect of environmental and mechanical factors. In order to make service life design realistic it is necessary to consider both of these factors acting simultaneously. This paper deals with the advanced modelling of concrete carbonation and chloride ingress into concrete using stochastic 1D and 2D models. Widely accepted models incorporated into the new fib Model Code 2010 are extended to include factors that reflect the coupled effects of mechanical and environmental loads on the durability and reliability of reinforced concrete structures. An example of cooling tower degradation by carbonation and an example of a bended reinforced concrete beam kept for several years in salt fog are numerically studied to show the capability of the stochastic approach. The modelled degradation measures are compared with experimental results, leading to good agreement.

좁은 치조골에 변형된 치조능 분할술/확장술을 이용한 임플란트 동시 식립 : 3 가지 증례보고 (Simultaneous Implant Placement with Modified Ridge Splitting/Expansion Technique in the Narrow Edentulous Alveolar Ridge : 3 Cases Report)

  • 이종빈;이재홍;김영택
    • 대한치과의사협회지
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    • 제53권8호
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    • pp.545-557
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    • 2015
  • The modified ridge splitting/expansion technique combined with guided bone regeneration (GBR) for implant surgery is used to expand the narrow and atrophied edentulous alveolar ridge. Also, the simultaneous implant placement after ridge splitting/expansion technique can reduce the treatment and healing time. This case report includes three patients with a narrow edentulous alveolar ridge of the 2 to 4mm. All three patients underwent a fracture of thin buccal cortical bone plate, and these defects were corrected by the use of the guided bone regeneration (GBR). After 7 to 18 months, all surgical area was stable, and all implant showed a good healing state on the clinical and radiographic examination. In conclusion, though this surgical method is technique sensitive, the modified ridge splitting/expansion technique combined with GBR for implant surgery is recommended for a horizontal augmentation in the narrow edentulous alveolar ridge.

Space Service Volume Augmented with Korean Positioning System at Geosynchronous Orbit

  • Kim, Gimin;Park, Chandeok;Lim, Deok Won
    • Journal of Positioning, Navigation, and Timing
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    • 제9권4호
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    • pp.327-336
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    • 2020
  • This study presents signal availability of inter-operable global navigation satellite system (multi-GNSS) combined with future Korean Positioning System (KPS), specifically at geosynchronous orbit (GSO). The orbit of KPS, which is currently under conceptual feasibility study, is first introduced, and the grid points for evaluating space service volume (SSV) at GSO are generated. The signal observabilities are evaluated geometrically between those grid points and KPS/GNSS satellites. Then, analyzed are the visibility averaged over time/space and outage time to not access one or four signals. The reduction of maximum outage time induced by KPS are presented with different maximum off-boresight angles depending on L1/E1/B1 and L5/L3/E5a/B2 frequencies. Our numerical analysis shows that the SSV of multi-GNSS combined with KPS provides up to 7 additional signals and could provide continuous observation time (zero outage time) of more than four GNSS or KPS signals for 3.20-14.83% of SSV grid points at GSO. Especially at GSO above North/South America and Atlantic region, the introduction of KPS reduces the outage duration by up to 63 minutes with L1/E1/B1 frequency.

모바일 마이크로블로깅(Mobile Microblogging) 서비스의 사용요인에 관한 연구 (A Research on Usage Factors of Mobile Microblogging Service)

  • 진정숙;조로사;박주석
    • 경영과학
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    • 제28권3호
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    • pp.83-94
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    • 2011
  • Microblogging is a Web2.0 technology that is used to manage online interpersonal relationship in SNS. Microblogging service allows the users to publish online brief text updates, usually less than 140~200 characters, sometimes images too. Recently, it becomes more and more popular. There are many reasons, the major one of which is that it can be perfectly combined with mobile. Based on technology acceptance model (TAM) and according to mobile service and microblogging service, this research adds four attributes : Perceived enjoyment, Habit, Mobility, Social Influence. It studies the factors that will impact on the way in which people use rapid developing Mobile Microblogging Service. This research will compare the influence factors and intension to use with the results from other studies with SNS and Mobile Microblogging Service, and then conclude the differences that can be generated in Microblogging.