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A Stochastic Modeling Approach for Interplanetary Supply Chain Planning

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Space(Science & Technology) 2023年第1期3卷 98-111页

作者： gregor Blossey Department of Information Systems Productionand Logistics ManagementUniversity of InnsbruckInnsbruckAustria Department of Business Informatics European University ViadrinaFrankfurt(Oder)Germany

The unique and complex challenges of sustainable interplanetary travel necessitate a novel space logistics paradigm,which is hereafter referred to as the interplanetary supply *** lay the groundwork for this anticipated paradigm shift,this work aims to introduce principles and methodologies of supply chain(SC)planning to the field of space *** this end,a stochastic multistage mixed integer linear programming model is proposed that explores the vision of a permanent human presence on Mars from a logistics *** model optimizes material flows,propellant production,and in-space infrastructure allocations to identify the optimal SC network ***,demand uncertainty at the Mars base is considered,which makes it the first model to investigate the effects of stochasticity in space logistics *** case studies are investigated,which incorporate data on Earth-Mars transfer windows and flight trajectories obtained through the National Aeronautics and Space Administration’s trajectory *** results reveal numerous interdependencies and,thus,highlight the need for holistic SC modeling approaches that go beyond the isolated mission planning of the extant *** instance,the findings show frequent interactions among spacecraft as they regularly engage in division of labor regarding cargo and propellant ***,complex propellant supply networks that involve strategic in-space infrastructure allocation and propellant production on celestial bodies are ***,the developed model provides valuable insights into the planning of a sustainable interplanetary travel,offers a new SC perspective,and lays the foundation for future research in this area.

关键词： travel hereafter sustainable

Development of a low-cost measurement system for cutting edge profile detection

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Chinese Optics Letters 2011年第7期9卷 33-36页

作者： gregor Gerstorfer Bernhard G.Zagar Institute for Measurement Technology Johannes Kepler University

The use of a compact disk （CD） pickup head as a displacement measurement system is described. The components contained in a pickup head are explained and how they are combined to obtain the functionality of a pickup head. The application of measuring a knife edge profile is introduced. The results reveal some insuffiencies with the current system. The cutting edge＇s radius of curvature can be estimated.

关键词： Development of a low-cost measurement system for cutting edge profile detection VCM

QoS Guided Min—Min Heuristic for Grid Task Scheduling

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Journal of Computer Science & Technology 2003年第4期18卷 442-451页

作者：何晓珊孙贤和 gregor von Laszewski Department of Computer Science Illinois Institute of Technology IL USA Mathematics and Computer Science Division Argonne National Laboratory IL USA

Task scheduling is an integrated component of computing. With the emergence of Grid and ubiquitous computing, new challenges appear in task scheduling based on properties such as security, quality of service, and lack of central control within distributed administrative domains. A Grid task scheduling framework must be able to deal with these issues. One of the goals of Grid task scheduling is to achieve high system throughput while matching applications with the available computing resources. This matching of resources in a non-deterministically shared heterogeneous environment leads to concerns over Quality of Service (QoS). In this paper a novel QoS guided task scheduling algorithm for Grid computing is introduced. The proposed novel algorithm is based on a general adaptive scheduling heuristics that includes QoS *** algorithm is evaluated within a simulated Grid environment. The experimental results show that the new QoS guided Min-Min heuristic can lead to significant performance gain for a variety of applications. The approach is compared with others based on the quality of the prediction formulated by inaccurate information.

关键词： QoS 任务调度网格计算服务质量非贡献计算

Probabilistic Assessment of Impact of Flexible Loads Under Network Tariffs in Low-voltage Distribution Networks

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Journal of Modern Power Systems and Clean Energy 2021年第4期9卷 951-962页

作者： Donald Azuatalam Archie C.Chapman gregor Verbic School of Electrical and Information Engineering The University of SydneySydneyNew South WalesAustralia

Given the historically static nature of low-voltage networks, distribution network companies do not possess the tools for dealing with an increasingly variable demand due to the high penetration of distributed energy resources (DERs). Within this context, this paper proposes a probabilistic framework for tariff design that minimises the impact of DER on network performance, stabilises the revenue of network company, and improves the equity of network cost allocation. To deal with the lack of customers’ response, we also show how DER-specific tariffs can be complemented with an automated home energy management system (HEMS) that reduces peak demand while retaining the desired comfort level. The proposed framework comprises a nonparametric Bayesian model which statistically generates synthetic load and PV traces, a hot-water-use statistical model, a novel HEMS to schedule customers’ controllable devices, and a probabilistic power flow model. Test cases using both energy- and demand-based network tariffs show that flat tariffs with a peak demand component reduce the customers’ cost, and alleviate network constraints. This demonstrates, firstly, the efficacy of the proposed tool for the development of tariffs that are beneficial for the networks with a high penetration of DERs, and secondly, how customers’ HEM systems can be part of the solution.

关键词： Battery energy storage system demand-based tariff distributed energy resource(DER) home energy management system(HEMS) low-voltage network solar photovoltaic(PV) thermostatically controlled load

Preventing Pressure Oscillations Does Not Fix Local Linear Stability Issues of Entropy-Based Split-Form High-Order Schemes

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Communications on Applied Mathematics and Computation 2022年第3期4卷 880-903页

作者： Hendrik Ranocha gregor J.Gassner Applied Mathematics Münster University of Münster48149 MünsterGermany Computer Electrical and Mathematical Science and Engineering(CEMSE)Division King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia Department of Mathematics and Computer Science Center for Data and Simulation ScienceUniversity of CologneCologneGermany

Recently,it was discovered that the entropy-conserving/dissipative high-order split-form discontinuous Galerkin discretizations have robustness issues when trying to solve the sim-ple density wave propagation example for the compressible Euler *** issue is related to missing local linear stability,i.e.,the stability of the discretization towards per-turbations added to a stable base *** is strongly related to an anti-diffusion mech-anism,that is inherent in entropy-conserving two-point fluxes,which are a key ingredi-ent for the high-order discontinuous Galerkin *** this paper,we investigate if pressure equilibrium preservation is a remedy to these recently found local linear stability issues of entropy-conservative/dissipative high-order split-form discontinuous Galerkin methods for the compressible Euler *** equilibrium preservation describes the property of a discretization to keep pressure and velocity constant for pure density wave *** present the full theoretical derivation,analysis,and show corresponding numerical results to underline our *** addition,we characterize numerical fluxes for the Euler equations that are entropy-conservative,kinetic-energy-preserving,pressure-equilibrium-preserving,and have a density flux that does not depend on the *** source code to reproduce all numerical experiments presented in this article is available online(https://***/10.5281/zenodo.4054366).

关键词： Entropy conservation Kinetic energy preservation Pressure equilibrium preservation Compressible Euler equations Local linear stability Summation-by-parts

A Sub-element Adaptive Shock Capturing Approach for Discontinuous Galerkin Methods

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Communications on Applied Mathematics and Computation 2023年第2期5卷 679-721页

作者： Johannes Markert gregor Gassner Stefanie Walch Department for Mathematics and Computer Science University of CologneWeyertal 86-9050931 CologneGermany Department for Mathematics and Computer Science Center for Data and Simulation ScienceUniversity of CologneWeyertal 86-9050931 CologneGermany I.Physikalisches Institut Center for Data and Simulation ScienceUniversity of CologneZülpicher Str.7750937 CologneGermany

In this paper,a new strategy for a sub-element-based shock capturing for discontinuous Galerkin(DG)approximations is *** idea is to interpret a DG element as a col-lection of data and construct a hierarchy of low-to-high-order discretizations on this set of data,including a first-order finite volume scheme up to the full-order DG *** dif-ferent DG discretizations are then blended according to sub-element troubled cell indicators,resulting in a final discretization that adaptively blends from low to high order within a single DG *** goal is to retain as much high-order accuracy as possible,even in simula-tions with very strong shocks,as,e.g.,presented in the Sedov *** framework retains the locality of the standard DG scheme and is hence well suited for a combination with adaptive mesh refinement and parallel *** numerical tests demonstrate the sub-element adaptive behavior of the new shock capturing approach and its high accuracy.

关键词： High-order methods Discontinuous Galerkin spectral element method Finite volume method Shock capturing Astrophysics Stellar physics

Geothermal Research in Austria—An Overview on Recent Activities of the Geological Survey of Austria

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地学前缘 2009年第S1期16卷 153-154页

作者： Goetzl gregor Geological Survey of Austria

Increasing demand on environmentally friendly energy supply enforces the need for geothermal research in *** geothermal utilization for recreational purposes and local heating has long tradition in Austria,the first geothermal heating facility has been launched in 1978 at Bad Waltersdorf, and the currently installed capacities exceed 60 MWth,fundamental researches,for example in

关键词： geothermal energy surface heat flow density utilization potential research strategy

Ultrafast Imaging of Electronic Relaxation in Ortho-xylene： New Features from Fragmentation-Ion Spectroscopy

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Chinese Physics Letters 2014年第12期31卷 130-133页

作者：刘玉柱 KNOPP gregor 肖韶荣 GERBER Thomas College of Physics and Opto-electronics Engineering Nanjing University of Information Science & Technology Nanjing 210044 Paul Scherrer Institute Villigen 5232 Switzerland

After light absorption, a molecule can undergo ra- diationless processes, and photophysics is one of the important general types. The photophysical pro- cesses involve internal conversion （IC） due to elec- tronic nonadiabaticity and intersystem crossing （ISC） induced by spin-orbit coupling. In polyatomic molecules that are excited IC and ISC to vibronic to higher electronic states, levels of lower electronic states are two dominant mechanisms. With the ad- vent of femtosecond ultrashort pulse, tracking and controlling the ultrafast photophysical processes be- come realizable. Due to the fact that ISC requires a change in the spin of an electron, it is usually a slower process than IC. However, extensive reports show that ultrafast competing ISC exists in a number of systems. Re- cently, Richter et al. reported femtosecond ISC in cytosine. Martinez-Fernandez et al. simulated the deactivation dynamics of photo-excited 6-thioguanine using a direct surface hopping dynamics approach Their simulations show that 6-thioguanine is another example of a system showing ultrafast ISC that can compete with IC in the same time scale. Both the spin-orbit and the dynamic couplings are important to describe realistically the excited state dynamics of 6-thioguanine. A similar phenomenon has also been evidenced in the S1 state of benzene. The exper- imental results show that the ultrafast decay of the S1 state is due to competing IC and ISC processes and both processes occur on a femtosecond timescale. Spin-orbit coupling is highly effective when the in- volved states are nearly isoenergetic.

关键词： Ultrafast Imaging Electronic Relaxation Fragmentation-Ion Spectroscopy

Proper ties of core-EP order in rings with involution

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Frontiers of Mathematics in China 2019年第4期14卷 715-736页

作者： gregor DOLINAR Bojan KUZMA Janko MAROVT Burcu UNGOR University of Ljubljana Faculty of Elec trical Engineering Trzaska 25 SI-1000 Ljubljana Slovenia University of Primorska Glagoljaska 8 SI-6000 Koper Slovenia University of Maribor Faculty of Economics and Business Razlagova 14 SI-2000 Maribor Slovenia IMFM Jadranska 19 SI-1000 Ljubljana Slovenia Faculty of Sciences Ankara University 06100 Tandogan Ankara Turkey

We study properties of a relation in *-rings, called the core-EP (pre)order which was introduced by H. Wang on the set of all n × n complex matrices [Linear Algebra Appl., 2016, 508: 289-300] and has been recently generalized by Y. Gao, J. Chen, and Y. Ke to *-rings [Filomat, 2018, 32: 3073- 3085]. We present new characterizations of the core-EP order in *-rings with identity and introduce the notions of the dual core-EP decomposition and the dual core-EP order in *-rings.

关键词： Drazin inverse core-EP decomposition pre-order ring