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Penalty Formulations and Trap-Avoidance Strategies for Solving Hard Satisfiability Problems

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Journal of Computer Science & Technology 2005年第1期20卷 3-17页

作者： BenjaminW.wah ZheWu DepartmentofElectricalandComputerEngineering UniversityofIllinoisUrbanaIL61801U.S.A. OracleCorporation OneOracleDriveNashuaNH03062U.S.A.

In this paper we study the solution of SAT problems formulated as discretedecision and discrete constrained optimization problems. Constrained formulations are better thantraditional unconstrained formulations because violated constraints may provide additional forces tolead a search towards a satisfiable assignment. We summarize the theory of extended saddle pointsin penalty formulations for solving discrete constrained optimization problems and the associateddiscrete penalty method (DPM). We then examine various formulations of the objective function,choices of neighborhood in DPM, strategies for updating penalties, and heuristics for avoidingtraps. Experimental evaluations on hard benchmark instances pinpoint that traps contributesignificantly to the inefficiency of DPM and force a trajectory to repeatedly visit the same set ofor nearby points in the original variable space. To address this issue, we propose and study twotrap-avoidance strategies. The first strategy adds extra penalties on unsatisfied clauses inside atrap, leading to very large penalties for unsatisfied clauses that are trapped more often and makingthese clauses more likely to be satisfied in the future. The second strategy stores information onpoints visited before, whether inside traps or not, and avoids visiting points that are close topoints visited before. It can be implemented by modifying the penalty function in such a way that,if a trajectory gets close to points visited before, an extra penalty will take effect and force thetrajectory to a new region. It specializes to the first strategy because traps are special cases ofpoints visited before. Finally, we show experimental results on evaluating benchmarks in the DIMACSand SATLIB archives and compare our results with existing results on GSAT, WalkSAT, LSDL, andGrasp. The results demonstrate that DPM with trap avoidance is robust as well as effective forsolving hard SAT problems.

关键词： knowledge representation and reasoning techniques of algorithms constraintsatisfaction boolean satisfiability penalty formulation saddle point search

Hsa-miR-214-3p inhibits breast cancer cell growth and improves the tumor immune microenvironment by downregulating B7H3

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Oncology research 2025年第1期33卷 103-121页

作者： Yan Lu Kang Wang Yuanhong Peng Meng chen Lin Zhong Luji Huang F u cheng Xindan Sheng Xin Yang Manzhao Ouyang George A Calin Zhiwei He china-America Cancer Research Institute Guangdong Medical University Dongguan 523808 China. GCP Center Shunde Hospital Southern Medical University (The First People's Hospital of Shunde Foshan) Shunde 528300 China. Department of Gastrointestinal Surgery Shunde Hospital Southern Medical University (The First People's Hospital of Shunde Foshan) Shunde 528300 China. The Second School of Clinical Medicine Southern Medical University Guangzhou 510080 China. Department of Translational Molecular Pathology The University of Texas MD Anderson Cancer Center Houston TX 77030 USA. Department of Oncology Shunde Hospital Southern Medical University (The First People's Hospital of Shunde Foshan) Shunde 528300 China.

Background:Immune checkpoint inhibitors play an important role in the treatment of solid tumors, but the currently used immune checkpoint inhibitors targeting programmed cell death-1 (PD-1), programmed cell death ligand-1 (PD-L1), and cytotoxic T-lymphocyte antigen-4 (CTLA-4) show limited clinical efficacy in many breast cancers. B7H3 has been widely reported as an immunosuppressive molecule, but its immunological function in breast cancer patients remains unclear.Methods:We analyzed the expression of B7H3 in breast cancer samples using data from the Cancer Genome Atlas Program (TCGA) and the Gene Expression Omnibus (GEO) databases. MicroRNAs were selected using the TarBase, miRTarBase, and miRBase databases. The regulatory role of the microRNA hsa-miR-214-3p on B7H3 was investigated through dual-luciferase reporter assays, which identified the specific action sites of interaction. The expression levels of B7H3 and hsa-miR-214-3p in human breast cancer tissues and adjacent normal tissues were quantified using Western blotting and quantitative PCR (qPCR). experiments were performed to observe the effects of modulating the expression of B7H3 or hsa-miR-214-3p on breast cancer cell proliferation and apoptosis. Additionally, the regulatory impact of hsa-miR-214-3p on B7H3 was examined. Enzyme-linked immunosorbent assays (ELISA) and flow cytometry were employed to assess the effects of co-cultured breast cancer cells and normal human peripheral blood mononuclear cells (PBMCs) on immune cells and associated cytokines.Results:In breast cancer tissues, the expression level of B7H3 is inversely correlated with that of hsa-miR-214-3p, as well as with the regulatory effects on breast cancercell behavior. Hsa-miR-214-3p was found to inhibit breast cancer cell growth by downregulating B7H3. Importantly, our research identified, for the first time, two binding sites for hsa-miR-214-3p on the 3' uTR of B7H3, both of which exert similar effects independently. Co-culture experime

关键词： B7H3 Breast cancer Hsa-miR-214-3p Immunotherapy

Zircon u-Pb dating of Shuiquangou alkaline complex intrusives, northwestern Hebei Province

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chinese Science Bulletin 1997年第9期42卷 772-775页

作者： Mo, ch Liang, HY Wang, XZ cheng, JP Li, HM Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Tianjin Institute of Geology and Mineral Resources Chinese Academy of Geological Sciences Tianjin China

SuPER large gold deposits related to alkaline intrusions have been found in America,Canada,Australia,Papua New Guinea and *** gold deposit with superlarge potentialhas also been found in Shuiquangou alkaline complex intrusions,northwestern Hebei Province,*** of the keys to resolving the possible genetic relationship between gold deposits andore-host alkaline intrusions is to determine their formation *** note dates the Shuiquan-gou intrusions with zircon u-Pb method.

关键词： alkaline intrusions Proterozoic Era zircon u-Pb dating gold deposit.

Inter-relationship of Various Results in Analysis of （14.0 MeV／u） Pb＋Pb Reaction using Mica and CN-85 Track Detectors

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chinese Physics Letters 2005年第1期22卷 69-71页

作者： F.N.Khattak E.u.Khan TabassumNasir J.J.Baluch F.u.Khan u.W.C. GomalUniversityDeraIsmailKhanPakistan RadiationPhysicsDivision PINSTECHNiloreIslamabadPakistan DepartmentofPhysics GomalUniversityDeraIsmailKhanPakistan

Two detector materials mica and cellulose-nitrate(CN)-85 have been used to study (14.0MeV/u) Pb + Pb reaction. Events of different multiplicities were registered in mica and CN-85 detectors using the 2π-geometry technique of solid state nuclear track detection. After removing the target material from the detectors the damaged trails in the detectors were revealed as tracks by proper chemical etching. The irradiated area of each sample was scanned and events of different multiplicities were traced. The binary events were bifurcated into elastic and inelastic events. The elastic binary events and three prong events, observed in the reaction, have been used to search out coefficients Cμν in the presence of both the detectors, for the reaction under study. using these coefficients 3- and 4-prong events have been analysed. From the detailed analysis of the results of (14.0MeV/u) Pb+Pb reaction, obtained from mica and CN-85 track detectors we observed a great resemblance of results obtained from the two detectors. Combining the results of both the detectors, we report some important outcomes.

关键词： CN-85轨迹探测器高能物理学铅原子碰撞反应固态

An Anti-Counterfeiting RFID Privacy Protection Protocol

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Journal of Computer Science & Technology 2007年第3期22卷 438-448页

作者： Xiaolan Zhang Brian king Department of Electrical and Computer Engineering University of Illinois U.S.A. Department of Electrical and Computer Engineering Indiana University Purdue University Indianapolis U.S.A.

The privacy problem of many RFID systems has been extensively studied. Yet integrity in RFID has not received much attention as regular computer systems. When we evaluate an identification protocol for an RFID system for anti-counterfeiting, it is important to consider integrity issues. Moreover, many RFID systems are accessed by multiple level trust parties, which makes comprehensive integrity protection even harder. In this paper, we first propose an integrity model for RFID protocols. Then we use the model to analyze the integrity problems in Squealing Euros protocol. Squealing Euros was proposed by Juels and Pappu for RFID enabled banknotes that will support anti-forgery and lawful tracing yet preserve individual＇s privacy. We analyze its integrity, we then discuss the problems that arise and propose some solutions to these problems. Then an improved protocol with integrity protection for the law enforcement is constructed, which includes an unforgeable binding between the banknote serial number and the RF ciphertext only readable to law enforcement. This same protocol can be applied in many other applications which require a privacy protecting anti-counterfeiting mechanism.

关键词： RFID security integrity privacy

Spectral Representation Theory for Dielectric Behavior of Nonspherical Cell Suspensions

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Communications in Theoretical Physics 2002年第7期38卷 113-120页

作者： HuANG Ji-Ping Yu Kin-wah LEI Jun SuN Hong Department of Physics the Chinese University of Hong Kong Shatin NT Hong Kong China Department of Physics the Chinese University of Hong Kong Shatin NT Hong Kong China Department of Applied Physics Shanghai Jiao Tong University Shanghai 200030 China Department of Applied Physics Shanghai Jiao Tong University Shanghai 200030 China Department of Physics University of California Berkeley California 94720-7300 U.S.A.

Recent experiments revealed that the dielectric dispersion spectrum of fission yeast cells in a suspension was mainly composed of two sub-dispersions. The low-frequency sub-dispersion depended on the cell length, while the high-frequency one was independent of it. The cell shape effect was simulated by an ellipsoidal cell model but the comparison between theory and experiment was far from being satisfactory. Prompted by the discrepancy, we proposed the use of spectral representation to analyze more realistic cell models. We adopted a shell-spheroidal model to analyze the effects of the cell membrane. It is found that the dielectric property of the cell membrane has only a minor effect on the dispersion magnitude ratio and the characteristic frequency ratio. We further included the effect of rotation of dipole induced by an external electric field, and solved the dipole-rotation spheroidal model in the spectral *** agreement between theory and experiment has been obtained.

关键词： dielectric relaxation, interfacial polarization, cell model

Polygeneration Study of Low-to-Medium Enthalpy Geothermal Reservoirs in Mexico

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Journal of Thermal Science 2021年第3期30卷 1077-1087页

作者： chÁVEZ Oscar GODÍNEZ Francisco Tecnológico Nacional de México/I.T.chihuahua.Av.Tecnológico 2909 C.P.31310ChihuahuaChihuahuaMéxico Instituto de Ingeniería Universidad Nacional Autónoma de MéxicoUNAMC.U.Ciudad de MéxicoC.P.04510México Polo universitario de Tecnología Avanzada Universidad Nacional Autónoma de MéxicoVía de la Innovación No.410Autopista Monterrey-Aeropuertokm.10 PIITC.P.66629Apodaca Nuevo LeónMéxico

This study combines the thermodynamic analysis of a polygeneration system along with the numerical modelling of the thermal behavior of geothermal reservoirs in Mexico to exploit their *** reservoir was modeled as a porous medium assuming a five-spot well configuration and local thermal *** heat conduction-convection along with the Laplace equations were solved to compute temperature distributions,the useful life and the optimum distance between injection-extraction *** predicted temperature and pressure of the geothermal fluid at the outlet of the reservoir were exploited in the polygeneration system consisting of:(1)a Rankine cycle,(2)an absorption refrigeration cycle,and(3)a heat *** developed approach allows calculating both the optimal distance between injection-extraction wells and the global(utilization)efficiency of six arrangements(each composed by a reservoir connected to a polygeneration system)by assuming that reservoirs have a lifespan of 30 *** also show that:(a)due to the low efficiency of the Rankine cycle,very little thermal energy is converted into electrical one;(b)not only the temperature and the size are important when evaluating the power production performance of reservoirs,but also the permeability plays a fundamental role;(c)the first law efficiency of the polygeneration system ranges from 41.9%to 43.7%;(d)the utilization efficiency of the six arrangements lies in the range between 25.8%and 31%.

关键词： polygeneration system geothermal reservoir local thermal equilibrium low-to-medium enthalpy

INTERACTION OF H_2O AND O_2 WITH INTERMETALLIC ALLOYS

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中国有色金属学会会刊：英文版 1999年第S1期9卷 100-105页

作者： Jinlin Wang and Yip wah chung Department of Materials Science and Engineering Northwestern university, Evanston, IL 60208, u.S.A.

The interaction of water vapor and oxygen with Ni 3(Al, Ti) and Ni 3Fe were investigated using Auger electron spectroscopy, X ray photo emission and thermal desorption. These studies showed that water dissociates on Ni 3(Al, Ti) (001) and polycrystalline Ni 3Fe to produce atomic hydrogen above 200 K, while remaining intact when exposed to Ni 3(Al, Ti) (111). In addition, pre adsorbed or co adsorbed oxygen on these surfaces strongly suppresses hydrogen production due to water dissociation. It was shown that adsorbed oxygen reacts with water vapor to produce surface hydroxyls, thus quenching the production of atomic hydrogen. Recent studies revealed an unexpected embrittling effect of boron in Ni 3Al in dry hydrogen. Experiments were proposed to elucidate the different possible roles of boron.

关键词： intermetallics Ni 3(Al Ti) Ni 3Fe interaction

Bayesian variable selection via a benchmark in normal linear models

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Statistical Theory and Related Fields 2021年第1期5卷 70-81页

作者： Jun Shao Kam-wah Tsui Sheng Zhang KLATASDS-MOE School of StatisticsEast China Normal University ShanghaiPeople’s Republic of China Department of Statistics University ofWisconsin-MadisonMadisonWIUSA

With increasing appearances of high-dimensional data over the past two decades,variable selections through frequentist likelihood penalisation approaches and their Bayesian counterparts becomes a popular yet challenging research area in *** a normal linear model with shrinkage priors,we propose a benchmark variable approach for Bayesian variable *** benchmark variable serves as a standard and helps us to assess and rank the importance of each covariate based on the posterior distribution of the corresponding regression *** a sparse Bayesian analysis,we use the benchmark in conjunction with a modified *** also develop our benchmark approach to accommodate models with covariates exhibiting group *** simulation studies are carried out to assess and compare the performances amongthe proposed approach and other *** real datasets are also analysed by using these methods for illustration.

关键词： Benchmark lasso sparse Bayes shrinkage prior