182,067 research outputs found

    The Container Selection Problem

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    We introduce and study a network resource management problem that is a special case of non-metric k-median, naturally arising in cross platform scheduling and cloud computing. In the continuous d-dimensional container selection problem, we are given a set C of input points in d-dimensional Euclidean space, for some d >= 2, and a budget k. An input point p can be assigned to a "container point" c only if c dominates p in every dimension. The assignment cost is then equal to the L1-norm of the container point. The goal is to find k container points in the d-dimensional space, such that the total assignment cost for all input points is minimized. The discrete variant of the problem has one key distinction, namely, the container points must be chosen from a given set F of points. For the continuous version, we obtain a polynomial time approximation scheme for any fixed dimension d>= 2. On the negative side, we show that the problem is NP-hard for any d>=3. We further show that the discrete version is significantly harder, as it is NP-hard to approximate without violating the budget k in any dimension d>=3. Thus, we focus on obtaining bi-approximation algorithms. For d=2, the bi-approximation guarantee is (1+epsilon,3), i.e., for any epsilon>0, our scheme outputs a solution of size 3k and cost at most (1+epsilon) times the optimum. For fixed d>2, we present a (1+epsilon,O((1/epsilon)log k)) bi-approximation algorithm

    The effects of tool container location on user performance in graphical user interfaces

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    A common way of organizing Windows, Icons, Menus, and Pointers (WIMP) interfaces is to group tools into tool containers, providing one visual representation. Common tool containers include toolbars and menus, as well as more complex tool containers, like Microsoft Office’s Ribbon, Toolglasses, and marking menus. The location of tool containers has been studied extensively in the past using Fitts’s Law, which governs selection time; however, selection time is only one aspect of user performance. In this thesis, I show that tool container location affects other aspects of user performance, specifically attention and awareness. The problem investigated in this thesis is that designers lack an understanding of the effects of tool container location on two important user performance factors: attention and group awareness. My solution is to provide an initial understanding of the effects of tool container location on these factors. In solving this problem, I developed a taxonomy of tool container location, and carried out two research studies. The two research studies investigated tool container location in two contexts: single-user performance with desktop interfaces, and group performance in tabletop interfaces. Through the two studies, I was able to show that tool container location does affect attention and group awareness, and to provide new recommendations for interface designers

    Immunity-based evolutionary algorithm for optimal global container repositioning in liner shipping

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    Global container repositioning in liner shipping has always been a challenging problem in container transportation as the global market in maritime logistics is complex and competitive. Supply and demand are dynamic under the ever changing trade imbalance. A useful computation optimization tool to assist shipping liners on decision making and planning to reposition large quantities of empty containers from surplus countries to deficit regions in a cost effective manner is crucial. A novel immunity-based evolutionary algorithm known as immunity-based evolutionary algorithm (IMEA) is developed to solve the multi-objective container repositioning problems in this research. The algorithm adopts the clonal selection and immune suppression theories to attain the Pareto optimal front. The proposed algorithm was verified with benchmarking functions and compared with four optimization algorithms to assess its diversity and spread. The developed algorithm provides a useful means to solve the problem and assist shipping liners in the global container transportation operations in an optimized and cost effective manner. © 2010 The Author(s).published_or_final_versionSpringer Open Choice, 21 Feb 201

    Considering the anchoring problem in robotic intelligent bin picking

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    Random Bin Picking means the selection by a robot of a particular item from a container (or bin) in which there are many items randomly distributed. Generalist robots and the Anchoring Problem should be considered if we want to provide a more general solution, since users want that it works with different type of items that are not known 'a priori'. Therefore, we are working on an approach in which robot learning and human-robot interaction are used to anchor control primitives and robot skills to objects and action symbols while the robot system is running, but we are limiting the scope to the packaging domain. In this paper we explain how to use our system to do anchoring in Robotic Bin Picking.Peer ReviewedPostprint (author's final draft

    Packing Circles Within Circular Containers: A New Heuristic Algorithm For The Balance Constraints Case

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    In this work we propose a heuristic algorithm for the layout optimization for disks installed in a rotating circular container. This is a unequal circle packing problem with additional balance constraints. It proved to be an NP-hard problem, which justifies heuristics methods for its resolution in larger instances. The main feature of our heuristic is based on the selection of the next circle to be placed inside the container according to the position of the system's center of mass. Our approach has been tested on a series of instances up to 55 circles and compared with the literature. Computational results show good performance in terms of solution quality and computational time for the proposed algorithm.36227930

    PERENCANAAN KEBUTUHAN KONTAINER UNTUK MEMINIMASI BIAYA PENGIRIMAN DENGAN MENGGUNAKAN INTEGER PROGRAMMING (Studi Kasus PT. Glori Industrial II Semarang)

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    PT. Glori Industrial II Semarang is one of company that has a garment export market. In the export of goods, the path often used is the sea route by using a cargo or containers. Loading cargo is one of the crucial issues that are often encountered. Selection of suitable containers and how the allocation of product items to be sent will directly affect the cost of shipping. Multicontainer based theories such as bin packing problem, multiple knapsack problem, bin covering, and min-cost covering integer programming, planning will be done on both these issues. In this case study, the proposed method is proposed using binary integer programming as a tool for finding solutions while solving an integer programming formulation using Lingo software assistance. Using 3rd September 2010 shipment data by 20 purchase orders (PO), found that the Container Requirement Planning using the proposed method will result in cost savings of U.S. $ 912.67. This figure can be quite large for local delivery fee charge. Keywords : Container Loading Planning, Container Requirement Planning, Integer programming

    Partitioned vs. Integrated Planning of Hinterland Networks for LCL Transportation

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    Utilizing existing transportation networks better and designing (parts of) networks involves routing decisions to minimize transportation costs and maximize consolidation effects. We study the concrete example of hinterland networks for the truck-transportation of less-than-container-load (LCL) ocean freight shipments: A set of LCL shipments is given. They have to be routed through the hinterland network to be transported to an origin port and finally to the destination port via ship. On their way, they can be consolidated in hubs to full-container-load (FCL) shipments. The overall transportation cost depends on the selection of the origin port and the routing and consolidation in the hinterland network. A problem of this type appears for the global logistics provider DB Schenker. We translate the business problem into a hub location problem, describe it mathematically, and discuss solution strategies. As a result, an integrated modeling approach has several advantages over solving a simplified version of the problem, although it requires more computational effort

    Smart container monitoring using custom-made WSN technology : from business case to prototype

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    This paper reports on the development of a prototype solution for tracking and monitoring shipping containers. Deploying wireless sensor networks (WSNs) in an operational environment remains a challenging task. We strongly believe that standardized methodologies and tools could enhance future WSN deployments and enable rapid prototype development. Therefore, we choose to use a step-by-step approach where each step gives us more insight in the problem at hand while shielding some of the complexity of the final solution. We observed that environment emulation is of the utmost importance, especially for harsh wireless conditions inside a container stacking. This lead us to extend our test lab with wireless link emulation capabilities. It is also essential to assess feasibility of concepts and design choices after every stage during prototype development. This enabled us to create innovative WSN solutions, including a multi-MAC framework and a robust gateway selection algorithm

    Optimasi Pola Pengumpulan dan Pengangkutan Sampah Kota Muara Teweh Melalui Pendekatan Zonasi

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    Physical development of Muara Teweh City accompanied by growing population and increasing solid waste generation strives the good management and treatment system of waste problem. Management and treatment of waste expected to overcome the problems resulting from the existing solid waste generation. One way to overcome this problem was through the selection pattern of waste collection and transportation that meet the criteria and aspects in the management of waste. Pattern of waste collection in Muara Teweh City which applied at this time comprised of; direct individual pattern, indirect individual pattern and direct communal pattern which can only serves a specific region only. Transportation which used in waste transportation were direct transportation pattern and a pattern by elevated container system. This transportation pattern spent the time to go around the city and the road to take and return to containing location. Thus, the pattern of waste collecting and transporting is still not optimally. According to standard, to a small town such as Muara Teweh pattern selected should be the waste collecting and transporting in accordance with the physical condition of the city and aspects of waste management
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