TY - JOUR A1 - Kieninger, Stefanie A1 - Donati, Luca A1 - Keller, Bettina G. T1 - Dynamical reweighting methods for Markov models JF - Current Opinion in Structural Biology N2 - Conformational dynamics is essential to biomolecular processes. Markov State Models (MSMs) are widely used to elucidate dynamic properties of molecular systems from unbiased Molecular Dynamics (MD). However, the implementation of reweighting schemes for MSMs to analyze biased simulations is still at an early stage of development. Several dynamical reweighing approaches have been proposed, which can be classified as approaches based on (i) Kramers rate theory, (ii) rescaling of the probability density flux, (iii) reweighting by formulating a likelihood function, (iv) path reweighting. We present the state-of-the-art and discuss the methodological differences of these methods, their limitations and recent applications. Y1 - 2020 U6 - https://doi.org/10.1016/j.sbi.2019.12.018 VL - 61 SP - 124 EP - 131 ER - TY - JOUR A1 - 品野, 勇治 T1 - MIPLIB と Hans Mittelmann’s benchmarks JF - 機関誌「オペレーションズ・リサーチ」 N2 - 混合整数計画法 (Mixed Integer Programming: MIP) は,MIP を解くソフトウェアである MIP ソルバが大規模な現実問題を解けるようになったこともあり,現実問題を解く有用な OR の手法として広く知られるようになった.しかしながら,MIP ソルバの開発に欠かせないベンチマーク・データセットおよび性能測定方法についてはそれほど広く知られているとは言い難い.ベンチマーク・データセットは注意を払って作成しないと,多くのバイアスがかかってしまう.それらのバイアスを可能な限りのぞき,真に有用なベンチマーク・テストの結果を得るためには複数の人数で多大な労力を割く必要がある.本稿では,そのような MIP ソルバ開発の背景として重要な役割を果たしてきた MIPLIB と Hans Mittelmann’s benchmarks について解説する.また,本稿において Hans Mittelmann’s benchmarks は,BENCHMARKS FOR OPTIMIZATION SOFTWAREのページ (http://plato.asu.edu/bench.html) に示されているベンチマークである. Y1 - 2020 UR - https://orsj.org/wp-content/corsj/or65-1/or65_1_49.pdf VL - 65 IS - 1 SP - 49 EP - 56 ER - TY - JOUR A1 - Kamada, Hiroki A1 - Yokoyama, Ryohei A1 - Shinano, Yuji A1 - Wakui, Tetsuya T1 - 階層的最適化手法の援用による エネルギー供給システムのロバスト最適設計 T1 - Robust Optimal Design of Energy Supply Systems With Aid of a Hierarchical Optimization Method JF - エネルギー・資源学会第36回エネルギーシステム・経済・環境コンファレンス講演論文集 N2 - A robust optimal design method of energy supply systems under uncertain energy demands has been proposed using a mixed- integer linear model for constituent equipment. A robust optimal design problem has been formulated as a three-level min-max- min optimization one by expressing uncertain energy demands by intervals, evaluating the robustness in a performance criterion based on the minimax regret criterion, and considering hierarchical relationships among design variables, uncertain energy demands, and operation variables. Since this problem must be solved by a special algorithm and is too difficult to solve even using a commercial solver, a hierarchical optimization approach has been applied to solve the problem but its application is limited only to small scale toy problems. In this paper, some strategies are introduced into the hierarchical optimization approach to enhance the computation efficiency for the purpose of applying the approach to large scale practical problems. In a case study, the proposed approach is applied to the robust optimal design of a cogeneration system with a complex configuration, and the validity and effectiveness of the method are ascertained. Y1 - 2020 SP - 730 EP - 735 ER - TY - JOUR A1 - Kamada, Hiroki A1 - Yokoyama, Ryohei A1 - Shinano, Yuji A1 - Wakui, Tetsuya T1 - 階層的最適化手法を用いた エネルギー供給システムのロバスト性評価 T1 - Evaluating Robustness of Energy Supply Systems Using a Hierarchical Optimization Method JF - 日本機械学会関西支部第95期定時総会講演会講演論文集 N2 - A robust optimal design method of energy supply systems under uncertain energy demands has been proposed using a mixed-integer linear model for constituent equipment. However, this method takes a long computation time, and thus it can be applied only to small-scale problems. In this paper, a hierarchical optimization method is applied to two types of optimization problems for evaluating robustness to solve them efficiently. In a case study, the proposed method is applied to a cogeneration system with a complex configuration, and the validity and effectiveness of the method are ascertained. Y1 - 2020 SP - 1 EP - 4 ER - TY - JOUR A1 - Takeuchi, Kotaro A1 - Yokoyama, Ryohei A1 - Shinano, Yuji A1 - Wakui, Tetsuya T1 - エネルギー供給システムの 設計および運用の階層的関係を考慮した最適化 (多目的最適設計へのモデル縮約の適用) T1 - Optimization of Energy Supply Systems in Consideration of Hierarchical Relationship Between Design and Operation (Application of Model Reduction to Multiobjective Optimal Design) JF - エネルギー・資源学会第36回エネルギーシステム・経済・環境コンファレンス講演論文集 N2 - To attain the highest performance of energy supply systems, it is necessary to determine design specifications optimally in consideration of operational strategies corresponding to seasonal and hourly variations in energy demands. Mixed-integer linear programming (MILP) methods have been applied widely to such optimal design problems. A hierarchical MILP method has been proposed to solve the problems very efficiently. In addition, by utilizing features of the hierarchical MILP method, a method of reducing model by clustering periods based on the optimal operational strategies of equipment has been proposed to search design solution candidates efficiently in the relaxed optimal design problem at the upper level. In this paper, these methods are applied to the multiobjective optimal design of a cogeneration system by considering the annual total cost and primary energy consumption as the objective functions to be minimized. Through a case study, it turns out that the model reduction by the operation-based time-period clustering is effective in terms of the computation efficiency when importance is given to the first objective function, while it is not when importance is given to the second objective function. Y1 - 2020 SP - 724 EP - 729 ER - TY - JOUR A1 - Takeuchi, Kotaro A1 - Yokoyama, Ryohei A1 - Shinano, Yuji A1 - Wakui, Tetsuya T1 - エネルギー供給システムの設計および運用の階層的関係を考慮した最適化 (k-メドイド法に基づく期間クラスタリングの適用) T1 - Optimization of Energy Supply Systems in Consideration of Hierachical Relationship Between Design and Operation (Application of Time-Period Clustering Based on k-Medoids Method) JF - 日本機械学会関西支部第95期定時総会講演会講演論文集 N2 - To attain the highest performance of energy supply systems, it is necessary to determine design specifications optimally in consideration of operational strategies corresponding to seasonal and hourly variations in energy demands. A hierarchical mixed-integer linear programming method has been proposed to solve such an optimal design problem efficiently. In this paper, a method of reducing model by clustering periods with the k-medoids method is applied to the relaxed optimal design problem at the upper level. Through a case study, it is clarified how the proposed method is effective to enhance the computation efficiency in a large scale optimal design problem. Y1 - 2020 SP - 1 EP - 4 ER - TY - CHAP A1 - Breuer, Thomas A1 - Bussieck, Michael A1 - Cao, Karl-Kien A1 - Fiand, Fred A1 - Gils, Hans-Christian A1 - Gleixner, Ambros A1 - Khabi, Dmitry A1 - Kempke, Nils A1 - Koch, Thorsten A1 - Rehfeldt, Daniel A1 - Wetzel, Manuel T1 - BEAM-ME: Accelerating Linear Energy Systems Models by a Massively Parallel Interior Point Method T2 - NIC Symposium 2020 Y1 - 2020 VL - 50 SP - 345 EP - 352 ER - TY - GEN A1 - Shinano, Yuji T1 - UG - Ubiquity Generator Framework v0.9.1 N2 - UG is a generic framework to parallelize branch-and-bound based solvers (e.g., MIP, MINLP, ExactIP) in a distributed or shared memory computing environment. It exploits the powerful performance of state-of-the-art "base solvers", such as SCIP, CPLEX, etc. without the need for base solver parallelization. UG framework, ParaSCIP(ug[SCIP,MPI]) and FiberSCIP (ug[SCIP,Pthreads]) are available as a beta version. For MIP solving, ParaSCIP and FiberSCIP are well debugged and should be stable. For MINLP solving, they are relatively stable, but not as thoroughly debugged. This release version should handle branch-and-cut approaches where subproblems are defined by variable bounds and also by constrains for ug[SCIP,*] ParaSCIP and FiberSCIP). Therefore, problem classes other than MIP or MINLP can be handled, but they have not been tested yet. v0.9.1: Update orbitope cip files. KW - parallelization framework KW - branch-and-bound parallelization KW - integer optimization Y1 - 2020 U6 - https://doi.org/10.12752/8508 ER - TY - CHAP A1 - Musial, Anna A1 - Zolnacz, Kinga A1 - Srocka, Nicole A1 - Kravets, Oleh A1 - Große, Jan A1 - Schneider, Philipp-Immanuel A1 - Olszewski, Jacek A1 - Poturaj, Krzystof A1 - Wojcik, Grzegorz A1 - Mergo, Pawel A1 - Dybka, Kamil A1 - Dyrkacz, Mariusz A1 - Dlubek, Michal A1 - Rodt, Sven A1 - Burger, Sven A1 - Zschiedrich, Lin A1 - Urbanczyk, Waclaw A1 - Sek, Grzegorz A1 - Reitzenstein, Stephan T1 - Stand-alone quantum dot-based single-photon source operating at telecommunication wavelengths T2 - 10th International Conference on Spontaneous Coherence in Excitonic Systems ICSCE10 Y1 - 2020 SP - 39 ER - TY - JOUR A1 - Beckenbach, Isabel T1 - Von Graphen zu Hypergraphen JF - OR News Y1 - 2020 SN - 1437-2045 IS - 70 ER -