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The essence of bidirectional programming

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Science China(Information Sciences) 2015年第5期58卷 76-96页

作者： FISCHER sebastian HU ZhenJiang PACHECO Hugo Department of Computing Science Christian-Albrechts-University of Kiel Information Systems Architecture Research Division National Institute of Informatics Department of Informatics The Graduate University for Advanced Studies (SOKENDAI) School of Electronics Engineering and Computer Science Peking University Department of Computer Science Cornell University

Bidirectional transformations(BXs), programs with a forward transformation and a backward transformation that maintain consistency between input and output, are routinely written in ways that do not let programmers specify their behavior completely. Several bidirectional programming languages exist to aid programmers in writing BXs with increased maintainability but decreased expressiveness. Such languages allow programmers to write BXs as one program for both directions, which is easier to maintain than separate programs for each direction. However, the maintainability provided by existing bidirectional languages comes at the cost of expressiveness because the ambiguity of synchronization is solved by default strategies which are hidden from programmers. The programmers’ inability to influence synchronization strategies has led to the proposal of a vast number of approaches that consider tailor-made synchronization strategies for particular *** this paper, we argue that such ambiguity is essential for BX and advocate that the synchronization strategy should not be hidden from programmers but considered from the start. We propose a novel approach to specifying so-called well-behaved bidirectional programs by their backward transformations, capable of expressing all aspects of a BX while retaining maintainability. Soundness of our approach results from a systematic analysis, based on existing mathematical concepts, of the instrumental laws of well-behaved BXs. We show that well-behaved BXs are uniquely determined by their backward transformations and corresponding forward transformations can be obtained for free.

关键词： bidirectional transformation software adaption and coevolution bidirectional programming

Exploiting global information in complex network repair processes

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Chinese Journal of Aeronautics 2017年第3期30卷 1086-1100页

作者： Tianyu WANG Jun ZHANG sebastian WANDELT School of Electronic and Information Engineering Beihang University 100083 Beijing ChinaBeoing Key Laboratory Jor Network-based Cooperative ATM 100083 Beijing China

Robustness of complex networks has been studied for decades,with a particular focus on network *** on network repair,on the other hand,has been conducted only very lately,given the even higher complexity and absence of an effective evaluation metric.A recently proposed network repair strategy is self-healing,which aims to repair networks for larger components at a low cost only with local *** this paper,we discuss the effectiveness and efficiency of self-healing,which limits network repair to be a multi-objective optimization problem and makes it difficult to measure its *** leads us to a new network repair evaluation *** the time complexity of the computation is very high,we devise a greedy ranking *** on both real-world and random networks show the effectiveness of our new metric and repair *** study contributes to optimal network repair algorithms and provides a gold standard for future studies on network repair.

关键词： Complex network Global information Greedy ranking Optimality Self-healing

Experimental and computational analysis of the coolant distribution considering the viscosity of the cutting fluid during machining with helical deep hole drills

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Advances in Manufacturing 2022年第2期10卷 235-249页

作者： Ekrem Oezkaya sebastian Michel Dirk Biermann Institute of Machining Technology Dortmund University of Technology(TU Dortmund)Dortmund 44227Germany

An experimental analysis regarding the distribution of the cutting fluid is very difficult due to the inaccessibility of the contact zone within the bore ***,suitable simulation models are necessary to evaluate new tool designs and optimize drilling *** this paper the coolant distribution during helical deep hole drilling is analyzed with high-speed *** particles are added to the cutting fluid circuit bya developed high-pressure mixing *** the evaluation of suitable particle size,particle concentration and coolant pressure,a computational fluid dynamics(CFD)simulation is validated with the experimental *** comparison shows a very good model quality with a marginal difference for the flow velocity of 1.57%between simulation and *** simulation considers the kinematic viscosity of the *** results show that the fluid velocity in the chip flutes is low compared to the fluid velocity at the exit of the coolant channels of the tool and drops even further between *** velocity and the flow pressure directly at the cutting edge decrease to such an extent that the fluid cannot generate a sufficient cooling or *** the CFD simulation a deeper understanding of the behavior and interactions of the cutting fluid is *** on these results further research activities to improve the coolant supply can be carried out with great potential to evaluate new tool geometries and optimize the machining process.

关键词： Computational fluid dynamics(CFD)analysis:Viscosity-Tracermicro particles Fluidbehavior Helical deep hole drilling

Conductivity improvement of Ce_(0.8)Gd_(0.2)O_(1.9) solid electrolyte

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Journal of Rare Earths 2009年第4期27卷 655-660页

作者： sebastian Molin Maria Gazda Piotr Jasinski Faculty of Electronics Telecommunications and Informatics Gdansk University of Technology ul.Narutowicza 11/12 80-952 Gdansk Poland Faculty of Applied Physics and Mathematics Gdansk University of Technology ul.Narutowicza 11/12 80-952 Gdansk Poland

Solid oxide fuel cells based on doped cefia electrolytes offer operating temperatures of -600℃. During recent years much atten- tion was aimed at successful powder preparation with high sinter activity and high conductivity. The properties of ceria electrolyte are very sensitive to impurities introduced during powder and electrolyte fabrication. One of the most successful and commercially available processes for the production of clean powders is based on the addition of several percent metallic cations that will react with impurities and segregate into the triple points of grain boundaries. In this work the results obtained from doping of CGO20 by 2% Ca and prepared by different routes were presented. The way of introducing Ca seemed to play an important role.

关键词： rare earth solid elecllolyte electrical properties impedance spectroscopy fuel cell solid oxide fuel cells (SOFC)

Charge carrier mobilities of organic semiconductors:ab initio simulations with mode-specific treatment of molecular vibrations

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npj Computational Materials 2022年第1期8卷 2199-2209页

作者： sebastian Hutsch Michel Panhans Frank Ortmann School of Natural Sciences Department of ChemistryTechnische Universität MünchenGarching b.MünchenGermany

The modeling of charge transport in organic semiconductors usually relies on the treatment of molecular vibrations by assuming a certain limiting case for all vibration modes,such as the dynamic limit in polaron theory or the quasi-static limit in transient localization *** opposite limits are each suitable for only a subset of ***,we present a model that combines these different *** is based on a separation of the vibrational spectrum and a quantum-mechanical treatment in which the slow modes generate a disorder landscape,while the fast modes generate polaron band *** apply the combined method to 20 organic crystals,including prototypical acenes,thiophenes,benzothiophenes,and their *** mobilities span several orders of magnitude and we find a close agreement to the experimental *** analysis reveals clear correlations to simple mobility predictors and a combination of them can be used to identify high-mobility materials.

关键词： theory semiconductors limit

An automated, 0.5 Hz nano-foil target positioning system for intense laser plasma experiments

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High Power Laser Science and Engineering 2017年第2期5卷 52-56页

作者： Ying Gao Jianhui Bin Daniel Haffa Christian Kreuzer Jens Hartmann Martin Speicher Florian H.Lindner Tobias M.Ostermayr Peter Hilz Thomas F.Rsch sebastian Lehrack franz Englbrecht sebastian Seuferling Max Gilljohann Hao Ding Wenjun Ma Katia Parodi Jorg Schreiber Lehrstuhl fur Medizinphysik Fakultat fUr PhysikLudwig-Maximilians-Universitat MiinchenAm Coulombwall 1D-85748GarchingGermany Max-Planck-lnstitut fur Quantenoptik D-85748 GarchingGermany peking University Beijing 100871PR China

We report on a target system supporting automated positioning of nano-targets with a precision resolution of 4 μm in three dimensions. It relies on a confocal distance sensor and a microscope. The system has been commissioned to position nanometer targets with 1 Hz repetition rate. Integrating our prototype into the table-top ATLAS 300 TW-laser system at the Laboratory for Extreme Photonics in Garching, we demonstrate the operation of a 0.5 Hz laser-driven proton source with a shot-to-shot variation of the maximum energy about 27% for a level of confidence of 0.95. The reason of laser shooting experiments operated at 0.5 Hz rather than 1 Hz is because the synchronization between the nano-foil target positioning system and the laser trigger needs to improve.

关键词： high intense laser nm thick target positioning system repetition rated laser-driven ion source

The use of carbon nanomaterials in membrane distillation membranes:a review

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Frontiers of Chemical Science and Engineering 2021年第4期15卷 755-774页

作者： sebastian Leaper Ahmed Abdel-Karim Patricia Gorgojo Department of Chemical Engineering and Analytical Science School of EngineeringThe University of ManchesterManchesterM139PLUK Water Pollution Research Department National Research CentreGiza 12622Egypt

Membrane distillation(MD)is a thermal-based separation technique with the potential to treat a wide range of water types for various applications and *** challenges remain however,which prevent it from becoming commercially widespread including moderate permeate flux,decline in separation performance over time due to pore wetting and high thermal energy ***,its attractive characteristics such as high rejection(ca.100%)of nonvolatile species,its ability to treat highly saline solutions under low operating pressures(typically atmospheric)as well as its ability to operate at low temperatures,enabling waste-heat integration,continue to drive research interests *** particular interest is the class of carbon-based nanomaterials which includes graphene and carbon nanotubes,whose wide range of properties have been exploited in an attempt to overcome the technical challenges that MD *** low dimensional materials exhibit properties such as high specific surface area,high strength,tuneable hydrophobicity,enhanced vapour transport,high thermal and electrical conductivity and *** use in MD has resulted in improved membrane performance characteristics like increased permeability and reduced fouling *** have also enabled novel membrane capabilities such as in-situ fouling detection and localised heat *** this review we provide a brief introduction to MD and describe key membrane characteristics and fabrication *** then give an account of the various uses of carbon nanomaterials for MD applications,focussing on polymeric membrane *** research directions based on the findings are also suggested.

关键词： carbon nanomaterials graphene membrane distillation desalination carbon nanotubes

Collisions and protein aggregations ahead: how aging affects ribosomal elongation dynamics

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Signal Transduction and Targeted Therapy 2022年第5期7卷 1369-1370页

作者： Pallab Maity sebastian Iben Department of Dermatology and Allergic Diseases Ulm UniversityUlmGermany

A recent study by Stein et al.1 deciphers how altered ribosomal elongation dynamics in aging contribute to a loss of protein homeostasis,***,the balance of protein synthesis,maintenance and degradation is severely affected in aging causing aging-associated neurodegenerative *** the contributions of disturbances in protein maintenance and degradation to the development of the disease have attracted much attention over the past decades,there is scant knowledge about protein synthesis dynamics in aging.

关键词： aging dynamics synthesis

No effect of invasive tree species on aboveground biomass increments of oaks and pines in temperate forests

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Forest Ecosystems 2024年第4期11卷 401-413页

作者： sebastian Bury Marcin K.Dyderski Institute of Dendrology Polish Academy of SciencesParkowa 562-035 KornikPoland

Prunus serotina and Robinia pseudoacacia are the most widespread invasive trees in Central *** addition,according to climate models,decreased growth of many economically and ecologically important native trees will likely be observed in the *** aimed to assess the impact of these two neophytes,which differ in the biomass range and nitrogen-fixing abilities observed in Central European conditions,on the relative aboveground biomass increments of native oaks Qucrcus robur and *** and Scots pine Pinus *** aimed to increase our understanding of the relationship between facilitation and competition between woody alien species and overstory native *** established 72 circular plots(0.05 ha)in two different forest habitat types and stands varying in age in western *** chose plots with different abundances of the studied neophytes to determine how effects scaled along the quantitative invasion ***,we collected growth cores of the studied native species,and we calculated aboveground biomass increments at the tree and stand ***,we used generalized linear mixed-effects models to assess the impact of invasive species abundances on relative aboveground biomass increments of native tree *** did not find a biologically or statistically significant impact of invasive *** or *** on the relative aboveground,biomass increments of native oaks and pines along the quantitative gradient of invader biomass or on the proportion of total stand biomass accounted for by *** neophytes did not act as native tree growth stimulators but also did not compete with them for resources,which would escalate the negative impact of climate change on pines and *** neophytes should not significantly modify the carbon sequestration capacity of the native *** work combines elements of the per capita effect of invasion with research on mixed forest management.

关键词： Invasion ecology Exotic trees Relative aboveground biomass increment Competition Facilitation Carbon sequestration