Download or read book Algorithms for Improved Efficiency in Transportation Models written by Christopher Allen Moyer and published by . This book was released on 1992 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Comparison of the Efficiency of Transportation Problem Algorithms written by William Peter MacMann and published by . This book was released on 1966 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optimization Models and Methods for Equilibrium Traffic Assignment written by Alexander Krylatov and published by Springer Nature. This book was released on 2019-11-26 with total page 231 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is focused on the discussion of the traffic assignment problem, the mathematical and practical meaning of variables, functions and basic principles. This work gives information about new approaches, methods and algorithms based on original methodological technique, developed by authors in their publications for the past several years, as well as corresponding prospective implementations. The book may be of interest to a wide range of readers, such as civil engineering students, traffic engineers, developers of traffic assignment algorithms etc. The obtained results here are to be used in both practice and theory. This book is devoted to the traffic assignment problem, formulated in a form of nonlinear optimization program. The most efficient solution algorithms related to the problem are based on its structural features and practical meaning rather than on standard nonlinear optimization techniques or approaches. The authors have carefully considered the meaning of the traffic assignment problem for efficient algorithms development.
Download or read book Probabilistic Models and Optimization Algorithms for Large scale Transportation Problems written by Jing Lu (Ph.D.) and published by . This book was released on 2020 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis tackles two major challenges of urban transportation optimization problems: (i) high-dimensionality and (ii) uncertainty in both demand and supply. These challenges are addressed from both modeling and algorithm design perspectives. The first part of this thesis focuses on the formulation of analytical transient stochastic link transmission models (LTM) that are computationally tractable and suitable for largescale network analysis and optimization. We first formulate a stochastic LTM based on the model of Osorio and Flötteröd (2015). We propose a formulation with enhanced scalability. In particular, the dimension of the state space is linear, rather than cubic, in the link’s space capacity. We then propose a second formulation that has a state space of dimension two; it scales independently of the link’s space capacity. Both link models are validated versus benchmark models, both analytical and simulation-based. The proposed models are used to address a probabilistic formulation of a city-wide signal control problem and are benchmarked versus other existing network models. Compared to the benchmarks, both models derive signal plans that perform systematically better considering various performance metrics. The second model, compared to the first model, reduces the computational runtime by at least two orders of magnitude. The second part of this thesis proposes a technique to enhance the computational efficiency of simulation-based optimization (SO) algorithms for high-dimensional discrete SO problems. The technique is based on an adaptive partitioning strategy. It is embedded within the Empirical Stochastic Branch-and-Bound (ESB&B) algorithm of Xu and Nelson (2013). This combination leads to a discrete SO algorithm that is both globally convergent and has good small sample performance. The proposed algorithm is validated and used to address a high-dimensional car-sharing optimization problem.
Download or read book Improved Algorithms and Computer Coding for Transportation Models written by Dirck Van Vliet and published by . This book was released on 1973 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Models and Algorithms for Public Transportation Scheduling written by Wei Ming and published by . This book was released on 2022-11 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Inproved algorithms and computer coding for transportation models written by and published by . This book was released on 1973 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bilevel Linear Programming Models and Algorithms for Freight Transportation written by Lorenzo Castelli and published by . This book was released on 2001 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transportation Network Optimization written by Long Zheng and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Efficient Algorithms for the Hitchcock Transportation Problem written by International Business Machines Corporation. Research Division and published by . This book was released on 1991 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: "We consider the Hitchcock transportation problem on n supply points and k demand points when n is much greater than k. The problem is solved in O(n2k log n + n2 log2n) time if we directly apply an efficient minimum cost flow algorithm. We show that the complexity can be improved to O(k2n log2n) time if n>k log k. Further, applying a geometric method named splitter finding and randomization, we improve the time complexity for a case in which the ratio c of the least supply and the maximum supply is bounded by n/k4 log n. Indeed, if c [
Download or read book Models and Algorithms for Multi Objective Transportation Optimization Problems written by Mo Zhang and published by Paths International Limited. This book was released on 2022-02-25 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the rapid development of trade globalization, transportation plays a critical role in global trade, and outsourcing transportation has become a common practice in the modern logistics industry. This book solved two problems in the modern logistics industry, which helped shippers save transportation costs and helped O2O takeout platforms improve decisions. This book studies two classes of decision-making optimization problems widely concerned in the modern logistics industry: transportation service procurement problems and online-to-offline food pickup and delivery problems.
Download or read book Transportation Service Network Design Models and Algorithms written by Thomas J. Watson IBM Research Center and published by . This book was released on 1997 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Network Design and Transportation Planning written by Thomas L. Magnanti and published by . This book was released on 1983 with total page 83 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Large scale Transportation Routing and Mode Optimization written by Yibo Dang and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the logistics industry, many resources are spent on handling the challenges in complex transportation planning problems. The growth of e-commerce demand scalable and hybrid delivery solutions that are in-time, cost-efficient, and clean. Increased workloads demand sophisticated scheduling and routing timelines. Therefore, governments and major logistics companies are launching different programs to promote sustainable distribution processes that leverage multiple transportation modes. In this way, the transportation network costs will be decreased and the carbon efficiency will be improved. Such increasing need for detailed and multimodal plans to larger transportation problems makes the current decision support tools indispensable. The low-quality solutions and the lack of big-data capability have concerned the practitioners for a long time. The problem of routing and scheduling with different types of carriers and modes have drawn limited attentions in previous research. There is no comprehensive research that discusses implementable models and algorithms with most real-world constraints on such transportation mode decision problem. The problem implies the design of long-haul transport, efficient last-mile deliveries to fulfill the demands within in strict time windows. Because it may take several days to cover a long-haul route, it is mandatory to consider breaks or layovers during the trip. Due to the capacity limit, some non-profitable deliveries are subcontracted to third-party carriers. This strategy allows the company to fill their vehicle fleets to the maximum. To further optimize the cost and carbon efficiencies of the vehicle fleets, different types of vehicles are to be evaluated. While the traditional diesel trailers can efficiently handle large amount of cargo, the travel costs and the greenhouse gas emissions cannot be negligible. While the technologies of electric vehicles are becoming mature, the driving-range issue and the high purchase cost still worry the industry. These challenges inhibit the success of a multimodal transportation network. In this dissertation, we investigate the three related optimization problems via meta-heuristics and mathematical programming – 1) a vehicle routing problem with common carriers and time regulation (VRPCCTR), in which the working hour limit is specified and third-party common carriers’ services are considered for unprofitable deliveries; 2) an extended version of the first problem where heterogeneous-sized vehicle fleets are involved (called HVRPCCTR); 3) the electric vehicles are introduced to the problem so that the mode decision becomes determining optimal routes between mixed vehicle types and sizes (called MVRPC) observing the time windows, recharging needs, service of hours regulations, and other constraints. In short, we study a new variant of the vehicle routing problem with three shipping modes – heterogeneous internal combustion vehicles, electric vehicles, and common carriers. Our main contributions are three-fold: We propose a novel meta-heuristic algorithm called Red-Black Ant Colony System for the problems, where the black ants are searching for regular routes using different sizes of vehicles whereas the red ants re-optimize within the common carrier deliveries to build efficient dedicated fleet routes. A developed tool can solve the mode decision problem for 150,000 deliveries. And its implementation has conducted over $5 million of dollars of savings for DHL and its customers annually. For each of the three problems, we give mixed integer linear programming (MILP) models and introduce strong valid inequalities. We prove the strengths of each set of valid inequalities by analyzing the linear relaxation bounds of the models. The endeavors of reducing the symmetry in the MILP models can be seen as the complexities grow from VRPCCTR through HVRPCCTR to MVRPC. We extend our work to incorporate green transportation plans. The recharges for electric vehicles and layover needs are efficiently modeled as renewable resources. This dissertation presents the first exact method based on a branch-and-cut- and-pricing algorithm for variants of MVRPC. The algorithm is tested on real data set from small sizes to medium sizes. Its performance and sensitivity are analyzed. The results show that the our algorithm can solve the problems up to 120 customers to exact optimality. Our results provide analytical insights and implementable large-scale algorithms for multimodal transportation networks of the next-generation logistic operations. The algorithms can also be utilized to study other types of scaling networks such as social networks, electrical grid, 3D printing models, etc. Other industries, such as manufacturing, digital communication, shared economy, etc., can also benefit from our results.
Download or read book Improved Efficiency of the Frank Wolfe Algorithm written by Larry J. LeBlanc and published by . This book was released on 1982 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selected Optimization Problems in Passenger Transportation Models Complexity and Algorithms written by Kateřina Böhmová and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Improved Transportation Models written by Daniel Brand and published by . This book was released on 1971 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
