• Title/Summary/Keyword: Time Allocation

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A Heuristic Algorithm of an Efficient Berth Allocation for a Public Container Terminal (공공 컨테이너 터미널의 효율적인 선석할당을 위한 발견적 알고리즘 개발에 관한 연구)

  • Keum, J.S.
    • Journal of Korean Port Research
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    • v.11 no.2
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    • pp.191-202
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    • 1997
  • As the suitability of berth allocation will ultimately have a significant influence on the performance of a berth, a great deal of attention should be given to berth allocation. Generally, a berth allocation problem has conflicting factors between servers and users. In addition, there is uncertainty in great extent caused by various factors such as departure delay, inclement weather on route, poor handling equipment, a lack of storage space, and other factors contribute to the uncertainty of arrival and berthing time. Thus, it is necessary to establish berth allocation planning which reflects the positions of interested parties and the ambiguity of parameters. For this, a berth allocation problem is formulated by fuzzy 0-1 integer programming introducing the concept of maximum Position Shift(MPS). But, the above approach has limitations in terms of computational time and computer memory when the size of problem is increased. It also has limitations with respect to the integration of other sub-systems such as ship planning system and yard planning system. For solving such problem, this paper focuses particularly on developing an efficient heuristic algorithm as a new technique of getting an effective solution. And also the suggested algorithm is verified through the illustrative examples and empirical appalicaton to BCTOC.

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Bin Packing-Exchange Algorithm for 3-Partition Problem (3-분할 문제의 상자 채우기-교환 알고리즘)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.22 no.4
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    • pp.95-102
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    • 2022
  • This paper proposed a linear time algorithm for a three-partition problem(TPP) in which a polynomial time algorithm is not known as NP-complete. This paper proposes a backtracking method that improves the problems of not being able to obtain a solution of the MM method using the sum of max-min values and third numbers, which are known polynomial algorithms in the past. In addition, the problem of MM applying the backtracking method was improved. The proposed algorithm partition the descending ordered set S into three and assigned to the forward, backward, and best-fit allocation method with maximum margin, and found an optimal solution for 50.00%, which is 5 out of 10 data in initial allocation phase. The remaining five data also showed performance to find the optimal solution by exchanging numbers between surplus boxes and shortage boxes at least once and up to seven times. The proposed algorithm that performs simple allocation and exchange optimization with less O(k) linear time performance complexity than the three-partition m=n/3 data, and it was shown that there could be a polynomial time algorithm in which TPP is a P-problem, not NP-complete.

Effective IPv6 Address Allocation Mechanism in All IP Wireless Networks (차세대 이동통신망에서 효율전인 IPv6 주소할당 방안)

  • 정현철;민상원
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.2B
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    • pp.240-249
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    • 2004
  • For the effective IP-based service implementation in the wireless network environment, involvement of IP-related technologies in wireless networks is inevitable and globally unique IPv6 address allocation to the mobile node has become an important issue. In the 3GPP's address allocation mechanism, IPv6 address allocation procedure is performed by the GGSN, which is normally located far from the mobile nodes. This causes IPv6 address allocation time delay and traffics to be longer and increased in the core network, respectively. In this paper, we propose a new IPv6 address allocation mechanism that is performed by Node B located in RAN. The proposed IPv6 address allocation mechanism can provide IPv6 addresses to mobile nodes within a more reduced time than existing 3GPP's IPv6 address allocation mechanism, and co-operates with existing mechanism as an overlay model to improve reliability of wireless networks. And, for implementation of the proposed address allocation mechanism, it needs not to change the structure of current wireless networks except for the some functional addendum of Node B.

A Register Scheduling and Allocation Algorithm for Low Power High Level synthesis (저전력 상위 레벨 합성을 위한 레지스터 스케줄링 및 할당알고리듬)

  • 최지영;인치호;김희석
    • Proceedings of the IEEK Conference
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    • 2000.11b
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    • pp.188-191
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    • 2000
  • This paper presents a register scheduling and allocation algorithm for high level synthesis. The proposed algorithm executes the low power scheduling to reduce the switching activity using shut down technique which was not unnecessary the calculation through the extraction DFG from VHDL description. Also, the register allocation algorithm determines the minimum register after the life time analysis of all variable. It is minimum the switching activity using graph coloring technique for low power consumption. The proposed algorithm proves the effect through various filter benchmark to adopt a new scheduling and allocation algorithm considering the low power.

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A Study on the Production Planning by Tool Allocation Methods on FMS (FMS에서 공구배분법을 고려한 생산계획에 관한 연구)

  • 우병훈;하정진
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.17 no.31
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    • pp.21-31
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    • 1994
  • In this research, tool allocation methods are studied in conjunction with loading and muting in FMSs. The objective function is to minimize production time while maximizing machine utilization of the FMS with several constraints. The proposed method has 2 steps. The first step is to determine tool allocation type with the proposed tool allocation method. The second step is to design loading models with routing. The effectiveness of the proposed FMS operation procedure is shown through numerical examples.

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Downlink Power Allocation for Relay Frequency Reuse (릴레이 주파수재사용을 위한 하향링크 전력 자원 할당)

  • Oh, Chang-Yoon
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.49 no.6
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    • pp.98-104
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    • 2012
  • We consider the optimum power allocation problem for downlink system throughput maximization in a 2 time slotted relay interference channel. Base station (BS) transmits power to Mobile Station (MS) and Relay Station (RS) in time slot 1 (orthogonal channel). In time slot 2, BS and RS transmit power to each MS, while causing cochannel interference to each other. The obtained optimum power allocation scheme allows simultaneous transmissions of BS and RS when the interference level in time slot 2 is low. However, when the interference level is high, RS shuts down its power. Numerical results are provided to support our analysis.

Determination of maximum allocation time for optimal RR scheduling (최적의 RR 스케줄링의 최대 할당 시간 결정)

  • Han, KyungHyun;Trang, Hoang Thi Huyen;Hwang, Seong Oun
    • Journal of Internet of Things and Convergence
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    • v.3 no.1
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    • pp.21-24
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    • 2017
  • Modern computers have to deal with multiple processes. The operating system uses scheduling to handle many processes with a small number of CPUs. Types of scheduling include FCFS, SJF, and RR. Of these, RR shall determine the maximum allocation time. In this paper, we analyzed the GLM algorithm for specific samples to find the optimal maximum allocation time. This analysis method allows us to specify the maximum allocation time according to the desired conditions.

Time-Slotted Scheduling Schemes for Multi-hop Concurrent Transmission in WPANs with Directional Antenna

  • Bilal, Muhammad;Kang, Moonsoo;Shah, Sayed Chhattan;Kang, Shin-Gak
    • ETRI Journal
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    • v.36 no.3
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    • pp.374-384
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    • 2014
  • To achieve high-speed (giga-bit) connectivity for short-range wireless multimedia applications, the millimeter-wave (mmWave) wireless personal area networks with directional antennas are gaining increased interest. Due to the use of directional antennas and mmWave communications, the probability of non-interfering transmissions increases in a localized region. Network throughput can be increased immensely by the concurrent time allocation of non-interfering transmissions. The problem of finding optimum time allocation for concurrent transmissions is an NP-hard problem. In this paper, we propose two enhanced versions of previously proposed multi-hop concurrent transmission (MHCT) schemes. To increase network capacity, the proposed schemes efficiently make use of the free holes in the time-allocation map of the MHCT scheme; thus, making it more compact.

A Bicriterion Scheduling Problem with Time/Cost Trade -offs (시간/비용의 트레이드-오프를 고려한 2목적 스케쥴링 문제)

  • 정용식
    • Proceedings of the Korea Society for Industrial Systems Conference
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    • 1998.10a
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    • pp.731-740
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    • 1998
  • This paper discusses a brcriterion approachto sequencing with time/cost trade-offs. The first problem is to minimize the total flow time and the maximum tardiness. And second is to the maximum tardiness and resource allocation costs. This approach , which produces an efficient frontier of possible schedules, has the advantage that it does not require the sequencing criteria to be measurable in the same units as the resource allocation cost. The basic single machine model is used to treat a class of problems in which the sequencing objective is to minimize the maximum completion penalty. It is further assumed that resource allocation costs can be represented by linear time/cost function.

병렬기계에서 실시간 공구할당 및 작업순서 결정 모델

  • 이충수;김성식;노형민
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1995.10a
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    • pp.880-884
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    • 1995
  • Manufacturing environment is getting characterized by unstable market demand,short product life cycle and timebased competition. For adapting this environment,machine tools have to be further versatile functionally in order to reduce part's set-up time. Unlike existing manufacturing systems mainly to focus on part flow, it is important to control tool flow using fast tool change device and tool delivery device in parallel machines consisting of versatile machine tools, because complete operations on a part can be performed on one machine tool in a single machine set-up. In this paper, under dynamic tool allocation strategy to share tools among machine tools, we propose a real-time tool allocation and operation esequence model with an objective of minimizing flow time using autonomy and negotiation of agents in parallel machines

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