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Optimization of thermomechanical processes in Cu-Cr-Zr lead frame alloy using neural networks and genetic algorithms

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science china(Technological sciences) 2005年第5期48卷 510-520页

作者： SU Juanhua1,2, LIU Ping2, DONG Qiming2 & LI Hejun1 1. College of Materials science and Engineering, Northwestern Polytechnical university, xi’an 710072, china 2. College of Materials science and Engineering, Henan university of science and Technology, Luoyang 471003, china 1. College of Materials science and Engineering Northwestern Polytechnical University 710072 Xi’an China 2. College of Materials science and Engineering Henan University of Science and Technology 471003 Luoyang China

The thermomechanical treatment process is effective in enhancing the properties of the lead frame copper alloy. In this study, an optimal pattern of the thermomechanical processes for Cu-Cr-Zr was investegated using an intelligent control technique consisting of neural networks and genetic algorithms. The input parameters of the artificial neural network (ANN) are the reduction ratio of cold rolling, aging temperature and aging time. The outputs of the ANN model are the two most important properties of hardness and conductivity. Based on the successfully trained ANN model, genetic algorithms (GA) are used to optimize the input parameters of the model and select perfect combinations of thermomechanical processing parameters and properties. The good generalization performance and optimized results of the integrated model are achieved.

关键词： Cu-Cr-Zr alloy, thermomechanical processing optimization, artificial neural network, genetic algorithms.

Distributed fiber optic sensors for tunnel monitoring:A state-of-the-art review

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3841-3863页

作者： Xuehui Zhang Honghu Zhu xi Jiang Wout Broere Geo-Engineering Section Department of Geoscience and EngineeringDelft University of TechnologyDelft2628CNthe Netherlands School of Earth sciences and Engineering Nanjing UniversityNanjing210023China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina

Distributed fiber optic sensors(DFOSs)possess the capability to measure strain and temperature variations over long distances,demonstrating outstanding potential for monitoring underground *** study presents a state-of-the-art review of the DFOS applications for monitoring and assessing the deformation behavior of typical tunnel infrastructure,including bored tunnels,conventional tunnels,as well as immersed and cut-and-cover *** systems based on Brillouin and Rayleigh scattering principles are both *** implementing DFOS monitoring,the fiber optic cable can be primarily installed along transverse and longitudinal directions to(1)measure distributed strains by continuously adhering the fiber to the structure’s surface or embedding it in the lining,or(2)measure point displacements by spot-anchoring it on the lining *** are four critical aspects of DFOS monitoring,including proper selection of the sensing fiber,selection of the measuring principle for the specific application,design of an effective sensor layout,and establishment of robust field sensor *** four issues are comprehensively discussed,and practical suggestions are provided for the implementation of DFOS in tunnel infrastructure monitoring.

关键词： Distributed fiber optic sensor(DFOS) Tunnel infrastructure Distributed strain sensing Point displacement monitoring Field instrumentation

Molecular cloning and functional analysis of two calcium associated cuticular protein genes in Neocaridina denticulata sinensis

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Journal of Oceanology and Limnology 2024年第5期42卷 1659-1672页

作者： xi GAO Mengmeng DUAN Yuying SUN Jiquan ZHANG School of Life sciences/Hebei Basic science Center for Biotic Interaction Hebei UniversityBaoding 071002China Institute of Life science and Green Development Hebei UniversityBaoding 071002China

The body surface of crustaceans is covered with a sturdy *** growth and development of crustaceans are realized through *** denticulata sinensis is a suitable candidate for crustacean scientific *** calcium-associated cuticular protein genes,named NdCAP-1 and NdCAP-2,were obtained from *** *** docking simulated the binding effect of both proteins and calcium ***-quantitative reverse transcription PCR results show that NdCAP-1 is expressed in D_(2-4) stage,NdCAP-2 expressed in D_(2-4) and A-B stages,and both were significantly expressed in the cephalothorax cuticle and ***,it was revealed that NdCAP-1 and NdCAP-2 are regulated by NdEcR-mediated 20 E signaling *** of NdCAP-1 and NdCAP-2 was observed to cause surface *** recombinant proteins(rNdCAP-1 and rNdCAP-2),obtained by prokaryotic expression,had calcium-binding and chitin-binding ability,inhibited formation of calcium carbonate *** results show that calcium-associated cuticular proteins play important roles in cuticle formation and calcification.

关键词： Neocaridina denticulata sinensis calcium-associated cuticular protein molting cycle RNAi calcium-binding ability

Surface pollen and modern vegetation in Southern xinjiang,china

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science china Earth sciences 2024年第2期67卷 510-530页

作者： Yun ZHANG Lixin CHEN Yaoyao xi Zhaochen KONG xianguo QIAO State Key Laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun130102China Institute of Botany Chinese Academy of SciencesBeijing100093China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China university of Chinese Academy of sciences Beijing100049China School of Geosciences and Resources China University of Geosciences(Beijing)Beijing100083China

The study of modern pollen,and vegetation can improve the accuracy of paleoenvironmental reconstruction based on fossil pollen data.A total of 188 pollen surface samples were collected from Southern xinjiang(34°00’–43°00’N,74°00’–94°00’E)in china,with an elevation range of 888–4530 *** pollen and vegetation were studied in the northern region of the Kunlun Mountains and the southern region of the Tianshan *** results showed that the surface pollen assemblages on the southern slope of the Tianshan Mountains(3530–1124 m)were divided into three pollen zones,namely,montane steppe,montane desert steppe,and montane *** zones were dominated by Artemisia,Chenopodiaceae,and Ephedra *** surface pollen assemblages in the eastern Pamir Plateau(4530–1287 m)could be divided into alpine meadow,montane desert steppe,and montane desert zones,which were predominantly characterized by Artemisia,Chenopodiaceae,and Asteraceae ***,the Southern Tarim Basin(3548–888 m)comprised montane desert steppe and montane desert zones,which was dominated by Artemisia and Chenopodiaceae *** geographic distribution of the surface pollen sites obtained using ArcGIS,the R-value,and Pearson correlation analyses indicated that the over-represented Picea and Pinus pollen were of external origin and were transported by wind,water(rivers),and ice(glacier movement).Over-representation of Ephedra and Nitraria pollen was mainly distributed in the montane desert and desert steppe zones,*** from Chenopodiaceae and Artemisia were over-represented and broadly distributed across Southern *** pollen was concentrated in areas with walnut trees,strongly indicating the presence of local parent *** to the Hybrid Singleparticle Lagrangian Integrated Trajectory model,more Pinus pollen was transported to the Pamir region by external airflows during spring and summer,resulting in its higher surface pollen *** elucidating t

关键词： Surface pollen Vegetation Distribution Picea Southern xinjiang

Continuity of the optimal value function and optimal solutions of parametric mixed-integer quadratic programs

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Applied Mathematics(A Journal of Chinese Universities) 2010年第4期25卷 391-399页

作者： CHEN Zhi-ping HAN You-pan Department of Scientific Computing and Applied Software, faculty of science, xi’an Jiaotong university, xi’an 710049, china Department of Scientific Computing and Applied Software Faculty of Science Xi’an Jiaotong University Xi’an China

To properly describe and solve complex decision problems, research on theoretical properties and solution of mixed-integer quadratic programs is becoming very important. We establish in this paper different Lipschitz-type continuity results about the optimal value function and optimal solutions of mixed-integer parametric quadratic programs with parameters in the linear part of the objective function and in the right-hand sides of the linear constraints. The obtained results extend some existing results for continuous quadratic programs, and, more importantly, lay the foundation for further theoretical study and corresponding algorithm analysis on mixed-integer quadratic programs.

关键词： Mixed-integer quadratic program optimal value function optimal solution.

Heterogeneous MXene-based films with graded electrical conductivity towards highly efficient EMI shielding and electrothermal heating

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Nano Research 2024年第8期17卷 7264-7274页

作者： Yu Zhang Guangcheng Zhang Zhonglei Ma Jianbin Qin xi Shen Department of Aeronautical and Aviation Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Shaanxi Key Laboratory of Macromolecular science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Research Institute for Sports science and Technology The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

The increasing need for electromagnetic interference(EMI)shielding of electronics in cold environments such as those in aircraft,space exploration,and wearable heaters to avoid hazardous icing conditions or hypothermia requires the development of thin and lightweight EMI shielding materials preferably by absorbing rather than reflecting electromagnetic(EM)waves while also generating heat through energy-efficient electrothermal ***,it is challenging to achieve absorption-dominant EMI shielding and energy-efficient electrothermal heating simultaneously in a thin and lightweight ***,we develop a heterogeneous composite film comprising a porous multi-walled carbon nanotubes(MWCNTs)/bacterial cellulose(BC)film and an aligned MXene/Ag nanowires(NWs)backing via a sequential vacuum filtration *** porous film contains random conductive networks of MWCNTs with moderate conductivity while the aligned MXene sheets atop Ag NWs network affords high conductivity in the backing,giving rise to graded electrical conductivity for absorption-dominant EMI *** increasing Ag NW coverage leads to significantly increased electrical conductivity without increasing the EM wave reflection as well as the density and thickness of the film,yielding excellent specific EMI shielding effectiveness(>8500 dB/(g·cm^(2))),low driving voltage for energy-efficient electrothermal heating(163℃at 2.5 V),and fast response time(60 s)at a low areal density of 0.015 mg/cm^(2).Combining EMI shielding and electrothermal heating,the heterogeneous film developed here are promising contenders for the protection of electronic equipment in low-temperature environment.

关键词： heterogenous composite film MXene electromagnetic interference(EMI)shielding thermal management

Breakthrough in Li-mediated continuous electrosynthesis of ammonia

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science china Chemistry 2024年第10期67卷 3191-3192页

作者： Fei Zhan chang Yu State Key Laboratory of Chemical Resource Engineering College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Fine Chemicals Liaoning Key Lab for Energy Materials and Chemical EngineeringSchool of Chemical EngineeringDalian University of TechnologyDalian 116024China

Ammonia(NH3)ranks among the manufactured chemicals,with an annual production surpassing 182 million tons[1],which is an indispensable raw material for fertilizer industry and has been recognized as a promising carbon-... 详细信息

关键词： ammonia Ammonia suppl

Luteolin promotes neuronogenesis in hippocampus of chronic unpredictable mild stress rats and primary hippocampus of fetal rats

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Journal of Traditional Chinese Medicine 2024年第4期44卷 670-679页

作者： LIU Tongtong ZHANG xi YANG Hui LIN xiaoyuan LIU Jian ZHANG xiuli GUO Dongwei ZHAO Hongqing ZOU Manshu LEI chang LONG Hongping LUO Yan xiANG Yun GE Jinwen WANG Yuhong MENG Pan Institute of Innovation and Applied Research in Chinese Medicine Hunan University of Chinese MedicineChangsha 410208China the Second People's Hospital of Hunan Province Changsha 410007China The First Affiliated Hospital Hunan University of Chinese MedicineChangsha 410007China Hunan Academy of Chinese Medicine Changsha 410013China

OBJECTIVE:To investigate the effects of luteolin on chronic unpredictable mild stress(CUMS)-induced depressive rats and corticosterone(CORT)-induced depressive primary hippocampal neurons,and to elucidate the mechanism behind the ***:The antidepressant mechanism of luteolin was studied by using CUMS rat model and primary hippocampal neurons in fetal *** vivo,novelty suppressed feeding,open-field and sucrose preference tests as well as Morris water maze were *** content of brain derived neurotrophic factor(BDNF),5-hydroxytryptamine(5-HT),norepinephrine(NE),and dopamine(DA)in serum were detected by enzyme-linked immunosorbent *** mechanisms of luteolin were explored based on neurotrophin and hippocampal neurogenesis,and *** of the septotemporal axis in hippocampus was assayed using the 5-bromo-2-deoxyuridine(BrdU),the expression of BDNF,neurotrophin-3(NT-3),and nerve growth factor(NGF)in hippocampus dentate gyrus region were measured by *** vitro,BDNF,NT-3,tropomyosin receptor kinase B(TrkB),and phosphorylated cyclic adenosine monophosphate responsive element binding protein(p-CREB)were detected through the high content analysis(HCA)to investigate neurotrophin and ***:Induction of CUMS in rats induced depressive symptoms,while luteolin significantly enhanced sucrose consumption,decreased feeding latency,increased locomotor activity,escape latency,distance of target quadrant and regulated the content of depressive-like *** analysis revealed that luteolin increased the abundance of new born neurons that had been labeled with BrdU,BrdU+neuronal nuclear antigen,and BrdU+doublecortin in septo-temporal axis of S2(mid-septal)and T3(mid-temporal).Moreover,expression of BDNF,NT-3,and NGF increased significantly in the septo-temporal axis of S2 and *** showed increased expression of BDNF,NT-3,TrkB and p-CREB in primary hippocampal ***:The results provided direct ev

关键词： fetal rats Survival

Exact satisfiability and phase transition analysis of the regular(k,d)-CNF formula

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Frontiers of Computer science 2024年第1期18卷 263-265页

作者： Guoxia NIE Daoyun XU xi WANG Zaijun ZHANG College of Computer science and Technology Guizhou UniversityGuiyang 550025China School of Mathematics and Statistics Qiannan Normal University for NationalitiesDuyun 558000China Key Laboratory of Industrial Automation and Machine Vision of Qiannan Duyun 558000China

1Introduction The satisfiability(SAT)problem has been considered the"seed"of other NP-complete *** regular partial exact(k,d)-SAT problem is an important extension of the SAT *** any(k,d)-CNF formula with a variable set V,V'is a proper subset of V,the problem involves determining whether a truth assignment set on V'exists such that only a literal in each clause is *** V'=V,it is a regular exact(k,d)-SAT ***,both experimental verifications and theoretical analyses of k-SAT problem have shown that the ratioα(clause constraint density)of the number of clauses m to the number of variables n is an important parameter affecting the satisfiability of the formula[1].However,the regular(k,d)-SAT problem has the same clause constraint density d/k.

关键词： formula constraint exact