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Semi-Automated Location Planning for Urban Bike-Sharing Systems

Markus Straub, Christian Rudloff, Anita Graser, Christian Kloimüllner, Günther R. Raidl, Markus Pajones, Felix Beyer
2018 Zenodo  
Functions D(x, t) and Q ( x, s) are modelled via linear programs (LP), for details we refer to Kloimüllner and Raidl (2017) .  ...  However, this is only possible for smaller instances up to about 300 cells according to our experiments in Kloimüllner and Raidl (2017) .  ... 
doi:10.5281/zenodo.1483821 fatcat:5pqlg2swnjd6rid3vszj3wco7a

Balancing Bicycle Sharing Systems: An Approach for the Dynamic Case [chapter]

Christian Kloimüllner, Petrina Papazek, Bin Hu, Günther R. Raidl
2014 Lecture Notes in Computer Science  
Operators of public bicycle sharing systems (BSSs) have to regularly redistribute bikes across their stations in order to avoid them getting overly full or empty. We consider the dynamic case where this is done while the system is in use. There are two main objectives: On the one hand it is desirable to reach particular target fill levels at the end of the process so that the stations are likely to meet user demands for the upcoming day(s). On the other hand operators also want to prevent
more » ... ns from running empty or full during the rebalancing process which would lead to unsatisfied customers. We extend our previous work on the static variant of the problem by introducing an efficient way to model the dynamic case as well as adapting our previous greedy and PILOT construction heuristic, variable neighborhood search and GRASP. Computational experiments are performed on instances based on real-world data from Citybike Wien, a BSS operator in Vienna, where the model for user demands is derived from historical data.
doi:10.1007/978-3-662-44320-0_7 fatcat:jnirzz74ljfmdmrjlhp3xbxzui

Kara: A System for Visualising and Visual Editing of Interpretations for Answer-Set Programs [chapter]

Christian Kloimüllner, Johannes Oetsch, Jörg Pührer, Hans Tompits
2013 Lecture Notes in Computer Science  
In answer-set programming (ASP), the solutions of a problem are encoded in dedicated models, called answer sets, of a logical theory. These answer sets are computed from the program that represents the theory by means of an ASP solver and returned to the user as sets of ground first-order literals. As this type of representation is often cumbersome for the user to interpret, tools like ASPVIZ and IDPDraw were developed that allow for visualising answer sets. The tool Kara, introduced in this
more » ... er, follows these approaches, using ASP itself as a language for defining visualisations of interpretations. Unlike existing tools that position graphic primitives according to static coordinates only, Kara allows for more high-level specifications, supporting graph structures, grids, and relative positioning of graphical elements. Moreover, generalising the functionality of previous tools, Kara provides modifiable visualisations such that interpretations can be manipulated by graphically editing their visualisations. This is realised by resorting to abductive reasoning techniques. Kara is part of SeaLion, a forthcoming integrated development environment (IDE) for ASP.
doi:10.1007/978-3-642-41524-1_20 fatcat:d3nlqjykiffgbhuq6vxn6ff24m

Balancing Bicycle Sharing Systems: An Analysis of Path Relinking and Recombination within a GRASP Hybrid [chapter]

Petrina Papazek, Christian Kloimüllner, Bin Hu, Günther R. Raidl
2014 Lecture Notes in Computer Science  
In bike sharing systems, a vehicle fleet rebalances the system by continuously moving bikes among stations in order to avoid rental stations to run entirely empty or full. We address the static problem variant assuming initial fill levels for each station and seek vehicle tours with corresponding loading instructions to reach given target fill levels as far as possible. Our primary objective is to minimize the absolute deviation between target and final fill levels for all rental stations.
more » ... ing upon a previously suggested GRASP hybrid, we investigate different approaches for hybridizing them with Path Relinking (PR) and simpler recombination operators. Computational tests on benchmark instances derived from a real world scenario in Vienna give insight on the impacts of the PR and recombination techniques and manifest that certain PR extension improve the results significantly. Ultimately, a hybrid exclusively searching a partial PR path in the neighborhood of the guiding solutions turns out to be most fruitful.
doi:10.1007/978-3-319-10762-2_78 fatcat:dv35cljjmnc55fgjhcm4fsdlvm

PILOT, GRASP, and VNS approaches for the static balancing of bicycle sharing systems

Marian Rainer-Harbach, Petrina Papazek, Günther R. Raidl, Bin Hu, Christian Kloimüllner
2014 Journal of Global Optimization  
We thank Matthias Prandtstetter, Andrea Rendl, Christian Rudloff, and Markus Straub from the Austrian Institute of Technology (AIT) for the collaboration in this project, constructive comments and for  ... 
doi:10.1007/s10898-014-0147-5 fatcat:qenu2r5jy5b73idvmvjtjg44su

Kara: A System for Visualising and Visual Editing of Interpretations for Answer-Set Programs [article]

Christian Kloimüllner, Johannes Oetsch, Jörg Pührer, Hans Tompits
2011 arXiv   pre-print
In answer-set programming (ASP), the solutions of a problem are encoded in dedicated models, called answer sets, of a logical theory. These answer sets are computed from the program that represents the theory by means of an ASP solver and returned to the user as sets of ground first-order literals. As this type of representation is often cumbersome for the user to interpret, tools like ASPVIZ and IDPDraw were developed that allow for visualising answer sets. The tool Kara, introduced in this
more » ... er, follows these approaches, using ASP itself as a language for defining visualisations of interpretations. Unlike existing tools that position graphic primitives according to static coordinates only, Kara allows for more high-level specifications, supporting graph structures, grids, and relative positioning of graphical elements. Moreover, generalising the functionality of previous tools, Kara provides modifiable visualisations such that interpretations can be manipulated by graphically editing their visualisations. This is realised by resorting to abductive reasoning techniques. Kara is part of SeaLion, a forthcoming integrated development environment (IDE) for ASP.
arXiv:1109.4095v2 fatcat:4zea4ewc25el7llinpbhcmnina

Efficient Consideration of Soft Time Windows in a Large Neighborhood Search for the Districting and Routing Problem for Security Control [chapter]

Bong-Min Kim, Christian Kloimüllner, Günther R. Raidl
2017 Lecture Notes in Computer Science  
For many companies it is important to protect their physical and intellectual property in an efficient and economically viable manner. Thus, specialized security companies are delegated to guard private and public property. These companies have to control a typically large number of buildings, which is usually done by teams of security guards patrolling different sets of buildings. Each building has to be visited several times within given time windows and tours to patrol these buildings are
more » ... nned over a certain number of periods (days). This problem is regarded as the Districting and Routing Problem for Security Control. Investigations have shown that small time window violations do not really matter much in practice but can drastically improve solution quality. When softening time windows of the original problem, a new subproblem arises where the minimum time window penalty for a given set of districts has to be found for each considered candidate route: What are optimal times for the individual visits of objects that minimize the overall penalty for time window violations? We call this Optimal Arrival Time Problem. In this paper, we investigate this subproblem in particular and first give an exact solution approach based on linear programming. As this method is quite time-consuming we further propose a heuristic approach based on greedy methods in combination with dynamic programming. The whole mechanism is embedded in a large neighborhood search (LNS) to seek for solutions having minimum time window violations. Results show that using the proposed heuristic method for determining almost optimal starting times is much faster, allowing substantially more LNS iterations yielding in the end better overall solutions.
doi:10.1007/978-3-319-55453-2_7 fatcat:5536ql56anfc5phjfsk3l7ryjy

An Online Development Environment for Answer Set Programming [article]

Elias Marcopoulos, Christian Reotutar, Yuanlin Zhang
2017 arXiv   pre-print
A more recent system, Kara, a standalone software by Kloimullner et al. [11] , deals with drawing only.  ... 
arXiv:1707.01865v1 fatcat:swly3illxjddvjma4r7swvt3fe

onlineSPARC: a Programming Environment for Answer Set Programming [article]

Elias Marcopoulos, Yuanlin Zhang
2018 arXiv   pre-print
Christian Reotutar also contributed to the early preparation of this paper. We thank Michael Gelfond and Yinan Zhang for their input and help.  ...  We thank Christian Reotutar, Evgenii Balai, Mbathio Diagne, Peter Lee, Maede Rayatidamavandi, Crisel Suarez, Edward Wertz and Shao-Lon Yeh for their contribution to the implementation of the environment  ...  A more recent system, Kara, a standalone software by Kloimullner et al. (Kloimüllner et al. 2013) , deals with drawing only.  ... 
arXiv:1809.08304v1 fatcat:qnrtl36m2bbkdn4vnm26boiqbe

Assessing the operational impact of tactical planning models for bike-sharing redistribution

Bruno Albert Neumann-Saavedra, Dirk Christian Mattfeld, Mike Hewitt
2021 Transportation Research Part A: Policy and Practice  
Dirk Christian Mattfeld: Conceptualization, Methodology, Software, Writing -original draft, Writing -review & editing.  ...  Kloimüllner et al. (2014) propose a multiobjective formulation minimizing unsatisfied demands for bikes and empty rack slots, the deviation from a target inventory of bikes at the end of the redistribution  ... 
doi:10.1016/j.tra.2021.06.003 fatcat:kozdeih5kvcltjjc5mj45ekpv4

Minimizing Multimodular Functions and Allocating Capacity in Bike-Sharing Systems [article]

Daniel Freund, Shane G. Henderson, David B. Shmoys
2020 arXiv   pre-print
Christian Kloimüllner, Petrina Papazek, Bin Hu, and Günther R Raidl. Bal- ancing bicycle sharing systems: an approach for the dynamic case.  ...  [2013], Raviv et al. [2013], Di Gaspero et al. [2013], Rainer-Harbach et al. [2013], Raidl et al. [2013], Ho and Szeto [2014], Kloimüllner et al. [2014], Kaspi et al. [2017], Forma et al. [2015], Alvarez-Valdes  ... 
arXiv:1611.09304v4 fatcat:hz32ytiwtna3vigxtrlentnsta

Metaheuristics for the districting and routing problem for security control

Michael Prischink, Günther Raidl, Benjamin Biesinger
2016
Danksagung Ich möchte mich bei Günther Raidl, Christian Kloimüllner und Benjamin Biesinger für die hervorragende Betreuung dieser Diplomarbeit bedanken.  ...  Introduction Michael Prischink, Christian Kloimüllner, Benjamin Biesinger, and Günther R. Raidl. Districting and routing for security control. In Hybrid Metaheuristics, 10th Int.  ... 
doi:10.34726/hss.2016.35903 fatcat:463vx652qvh6dozduhw4tdf72e

The Internet of Federated Things (IoFT): A Vision for the Future and In-depth Survey of Data-driven Approaches for Federated Learning [article]

Raed Kontar, Naichen Shi, Xubo Yue, Seokhyun Chung, Eunshin Byon, Mosharaf Chowdhury, Judy Jin, Wissam Kontar, Neda Masoud, Maher Noueihed, Chinedum E. Okwudire, Garvesh Raskutti (+3 others)
2021 arXiv   pre-print
Kloimüllner and Günther R Raidl.  ...  [124] Pavel Izmailov, Dmitrii Podoprikhin, Timur Garipov, [111] Christian Horn and Jörg Krüger. Feasibility of con- Dmitry Vetrov, and Andrew Gordon Wilson.  ... 
arXiv:2111.05326v1 fatcat:bbgdhtuqcrhstgakt2vxuve2ca