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IMPROVING SOLVER PERFORMANCE THROUGH REDUNDANCY

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Journal of Systems Science and Systems Engineering 2016年第3期25卷 303-325页

作者： Eduardo Lalla-Ruiz stefan Voβ Department of Computer Engineering and Systems University of La Laguna Spain Institute of Information Systems (IWI) University of Hamburg Germany Eseuela de Ingenierla Industrial Pontificia Universidad Catolica de Valparaiso (PUCV) Chile

It is well known that hierarchies of mathematical programming formulatlons with different numbers of variables and constraints have a considerable impact regarding the quality of solutions obtained once these formulations are fed to a commercial solver. In addition, even if dimensions are kept the same, changes in formulations may largely influence solvability and quality of results. This becomes evident especially if redundant constraints are used. We propose a related framework for information collection based on these constraints. We exemplify by means of a well-known combinatorial optimization problem from the knapsack problem family, i.e., the multidimensional multiple-choice knapsack problem （MMKP）. This incorporates a relationship of the MMKP to some generalized set partitioning problems. Moreover, we investigate an application in maritime shipping and logistics by means of the dynamic berth allocation problem （DBAP）, where optimal solutions are reached from the root node within the solver.

关键词： Erraticism redundant constraints multidimensional multiple-choice knapsack problem,dynamic berth allocation problem

Pathological tumor response to neoadjuvant therapy in borderline resectable pancreatic cancer

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Hepatobiliary & Pancreatic Diseases International 2019年第4期18卷 305-306页

作者： stefan Heinrich General Visceral and Transplantation Surgery University Hospital of Mainz

Surgery is the standard therapy for pancreatic ductal adenocarcinoma(PDAC).After the dramatic decline of operative mortality over the past decades,the indications for pancreas resections have been continuously extended:currently resections of the portal/superior mesenteric vein are considered standard by many centers,and even arterial resections are under *** these changes,different expert groups have defined resectability criteria containing a grey zone(“borderline resectable disease”)of tumors,which may be technically resectable with appropriate surgical expertise,but resection inherits an increased risk of an R1-resection[1].

关键词： Surgery mortality operative

Risk-Layering for Indirect Effects

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International Journal of Disaster Risk Science 2021年第5期12卷 770-778页

作者： stefan Hochrainer-Stigler Karina Reiter IIASA-International Institute for Applied Systems Analysis A-2361 Laxenburg.Austria

Environmental risks are one of the greatest threats in the twenty-first *** in the last years,the cascading impacts and risks associated with such events have received great attention as economic losses and consequences have mounted in their *** concerns about these ripple effects are rising,strategies to prevent and manage indirect risks are in urgent ***,such effects are currently barely considered in most countries and can seriously threaten global agendas such as achieving the Sustainable Development Goals by 2030 or the targets set out in the Sendai Framework for Disaster Risk Reduction *** discuss how the concept of risk-layering,which,though already applied in disaster risk management,could be expanded to include indirect *** point out some of the benefits,limitations,and ways forward for using this *** do so,we first delineate the transition of the risk-layering concept,which originated from the insurance industry,from its original use to its application in a wider *** bring special focus to the application of risk-layering in disaster risk management and identify strategies that allow for the inclusion of indirect *** main suggestion is that,while a probabilistic approach is appropriate for evaluating direct risks,a focus on connectedness is appropriate for indirect risks,which still allows for an easy link to direct ***,so we argue,facilitates more comprehensive risk management systems apt to deal with the multi-dimensional challenges ahead.

关键词： Connectedness Indirect risks Natural hazards and disasters Risk-layering Risk management

Analysis of the Caratheodory's Theorem on Dynamical System Trajectories Under Numerical Uncertainty

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IEEE/CAA Journal of Automatica Sinica 2018年第4期5卷 787-793页

作者： Pavel Osinenko Grigory Devadze stefan Streif Automatic Control and System Dynamics Laboratory Technische Universitat Chemnitz09107 ChemnitzGermany IEEE

The current work proposes a new and constructive proof for the Caratheodory's theorem on existence and uniqueness of trajectories of dynamical systems. The key concern is the numerical uncertainty, i.e., the discrepancy between mathematical proofs, algorithms, and their implementations, which may affect the correct functioning of a control system. Due to growing demands on security and compliance with specifications,correctness of the control system functioning is becoming ever more important. Since in both dynamical systems and many control design approaches, one of the central notions is the system trajectory, it is important to address existence and uniqueness of system trajectories in a way which incorporates numerical uncertainty. Constructive analysis is a particular approach to formalizing numerical uncertainty and is used as the basis of the current work. The major difficulties of guaranteeing existence and uniqueness of system trajectories arise in the case of systems and controllers which possess discontinuities in time,since classical solutions to initial value problems do not *** issue is addressed in Caratheodory's theorem. A particular constructive variant of the theorem is proven which covers a large class of problems found in practice.

关键词： Constructive analysis Caratheodory’s theorem dynamical systems

Managing stress granule disassembly with ubiquitin and its cousin

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Signal Transduction and Targeted Therapy 2021年第12期6卷 3377-3378页

作者： stefan Müller Institute of Biochemistry II Gustav Embden ZentrumGoethe University FrankfurtFaculty of MedicineFrankfurtGermany

Recently,Maxwell et al.1 revealed a critical function of ubiquitylation in stress granule(SG)disassembly upon recovery from heat *** are continuously exposed to endogenous or environmental *** stress endangers DNA integrity,whereas proteotoxic stress causes an imbalance in protein homeostasis(proteostasis).Genotoxic insults activate DNA damage response pathways that halt the cell-cycle progression and initiate DNA *** quality control(PQC)systems in turn safeguard the integrity of the proteome and prepare for the restart of cellular activities upon stress *** genome and proteome integrity pathways are orchestrated by ubiquitin signaling and the ubiquitin-proteasome system(UPS).

关键词： stress aging integrity

A customizable,low-power,wireless,embedded sensing platform for resistive nanoscale sensors

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Microsystems & Nanoengineering 2022年第1期8卷 111-121页

作者： stefan Nedelcu Kishan Thodkar Christofer Hierold Micro-and Nanosystems Department of Mechanical and Process EngineeringETH ZurichTannenstrasse 38092 ZurichSwitzerland

Customizable,portable,battery-operated,wireless platforms for interfacing high-sensitivity nanoscale sensors are a means to improve spatiotemporal measurement coverage of physical *** a platform can enable the expansion of IoT for environmental and lifestyle *** we report a platform capable of acquiring currents ranging from 1.5 nA to 7.2μA full-scale with 20-bit resolution and variable sampling rates of up to 3.125 *** addition,it features a bipolar voltage programmable in the range of-10 V to+5 V with a 3.65 mV resolution.A Finite State Machine steers the system by executing a set of embedded *** FSM allows for dynamic,customized adjustments of the nanosensor bias,including elevated bias schemes for self-heating,measurement range,bandwidth,sampling rate,and measurement time ***,it enables data logging on external memory(SD card)and data transmission over a Bluetooth low energy *** average power consumption of the platform is 64.5 mW for a measurement protocol of three samples per second,including a BLE advertisement of a 0 dBm transmission power.A state-of-the-art(SoA)application of the platform performance using a CNT nanosensor,exposed to NO_(2) gas concentrations from 200 ppb down to 1 ppb,has been *** sensor signals are measured for NO_(2) concentrations of 1 ppb,the 3σlimit of detection(LOD)of 23 ppb is determined(1σ:7 ppb)in slope detection mode,including the sensor signal variations in repeated *** platform’s wide current range and high versatility make it suitable for signal acquisition from resistive nanosensors such as silicon nanowires,carbon nanotubes,graphene,and other 2D *** with its overall low power consumption,the proposed platform is highly suitable for various sensing applications within the context of IoT.

关键词： power IoT enable

Biomimetic Precipitation of Uniaxially Grown Calcium Phosphate Crystals from Full-Length Human Amelogenin Sols

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Journal of Bionic Engineering 2011年第2期8卷 114-121页

作者： Vuk Uskokovie Wu Li stefan Habelitz Division of Biomaterials and Bioengineering Department of Preventive and Restorative Dental Sciences University of Calil'ornia 707 Parnassus Avenue San Francisco CA 94143 USA Department of Orofacial Sciences University of California 513 Parnassus Avenue San Francisco CA 94143 USA

Human dental enamel forms over a period of 2 4 years by substituting the enamel matrix, a protein gel mostly composed of a single protein, amelogenin with fibrous apatite nanocrystals. Self-assembly of a dense amelogenin matrix is presumed to direct the growth of apatite fibers and their organization into bundles that eventually comprise the mature enamel, the hardest tissue in the mammalian body. This work aims to establish the physicochemical and biochemical conditions for the synthesis of fibrous apatite crystals under the control of a recombinant full-length human amelogenin rnatrix in combination with a pro- grammable titration system. The growth of apatite substrates was initiated from supersaturated calcium phosphate solutions in the presence of dispersed amelogenin assemblies. It was shown earlier and confirmed in this study that binding of amelogenin onto apatite surfaces presents the first step that leads to substrate-specific crystal growth. In this work, we report enhanced nucleation and growth under conditions at which amelogenin and apatite carry opposite charges and adsorption of the protein onto the apatite seeds is even more favored. Experiments at pH below the isoelectric point of amelogenin showed increased protein binding to apatite and at low Ca/P molar ratios resulted in a change in crystal morphology from plate-like to fibrous and rod-shaped. Concentrations of calcium and phosphate ions in the supernatant did not show drastic decreases throughout the titration period, indicating controlled precipitation from the protein suspension metastable with respect to calcium phosphate. It is argued that amelobtasts in the developing enamel may vary the density of the protein matrix at the nano scale by varying local pH, and thus control the interaction between the mineral and protein phases. The biomimetic experimental setting applied in this study has thus proven as convenient for gaining insight into the fundamental nature of the process ofamelogenesi

关键词： enamel amelogenin biomineralization apatite biomimetics

Altered electroencephalographic networks in developmental dyslexia after remedial training:a prospective case-control study

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Neural Regeneration Research 2021年第4期16卷 734-743页

作者： Juliana A.Dushanova stefan ATsokov Institute of Neurobiology Bulgarian Academy of SciencesSofiaBulgaria

Electroencephalographic studies using graph theoretic analysis have found aberrations in functional connectivity in children with developmental ***,how the training with visual tasks can change the functional connectivity of the semantic network in developmental dyslexia is still *** looked for differences in local and global topological properties of functional networks between 21 healthy controls and 22 dyslexic children(8–9 years old)before and after training with visual tasks in this prospective case-control *** minimum spanning tree method was used to construct the subjects’brain networks in multiple electroencephalographic frequency ranges during a visual word/pseudoword discrimination *** found group differences in the theta,alpha,beta and gamma bands for four graph measures suggesting a more integrated network topology in dyslexics before the training compared to *** training,the network topology of dyslexic children had become more segregated and similar to that of the *** theθ,αandβ1-frequency bands,compared to the controls,the pre-training dyslexics exhibited a reduced degree and betweenness centrality of the left anterior temporal and parietal *** simultaneous appearance in the left hemisphere of hubs in temporal and parietal(α,β1),temporal and superior frontal cortex(θ,α),parietal and occipitotemporal cortices(β1),identified in the networks of normally developing children was not present in the brain networks of *** training,the hub distribution for dyslexics in the theta and beta1 bands had become similar to that of the *** summary,our findings point to a less efficient network configuration in dyslexics compared to a more optimal global organization in the *** is the first study to investigate the topological organization of functional brain networks of Bulgarian dyslexic *** for the study was obtained from the Ethics Committee of the Institute of Neur

关键词： adjusted post-training network developmental dyslexia EEG frequency oscillations functional connectivity visual training tasks visual word/pseudoword discrimination

A neuron's ambrosia: non-autonomous unfolded protein response of the endoplasmic reticulum promotes lifespan

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Neural Regeneration Research 2022年第2期17卷 309-310页

作者： stefan Homentcovschi Ryo Higuchi-Sanabria Department of Molecular&Cellular Biology University of CaliforniaBerkeleyCAUSA

The ability to protect cellular components in the face of deleterious conditions, such as exposure to chemical poisons, damaging radiation, or excessive heat, is crucial to organismal viability.

关键词： autonomous delete exposure