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基于复数滤波器组调制的MC-CDMA系统及其性能(英文)

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苏州大学学报（自然科学版） 2002年第3期18卷 77-83页

作者：包志华章国安南通工学院信息工程系江苏南通226007

优化生成了用于多载波基函数的复数滤波器组 ,给出了基于复数滤波器组调制的MC -CDMA系统模型 ,并分析比较了系统下行链路采用EGC ,MRC和ORC三种合并检测方法时在瑞利多径衰落信道下的性能 ,系统采用EGC方法时的性能优于采用MRC和ORC方... 详细信息

优化生成了用于多载波基函数的复数滤波器组 ,给出了基于复数滤波器组调制的MC -CDMA系统模型 ,并分析比较了系统下行链路采用EGC ,MRC和ORC三种合并检测方法时在瑞利多径衰落信道下的性能 ,系统采用EGC方法时的性能优于采用MRC和ORC方法时的性能 .

关键词：复数滤波器组多载波通信码分多址

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Aerodynamic Optimization and Flow Mechanism for a Compressor Cascade at Low Reynolds Number

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Journal of Thermal Science 2025年第1期34卷 92-109页

作者： LI Lin zhang Jianshe CHEN Caiyan TAN Wei zhang Yanfeng Key Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of Sciences University of Chinese Academy of Sciences National Key Laboratory of Science and Technology on Advanced Light-duty Gas-turbine

Low-Reynolds-number effect is an important factor affecting the performance of compressors and other main components of high-altitude long-endurance unmanned aerial *** improve the flow condition and reduce flow loss under the condition of high altitude and low Reynolds number(Re),this paper proposes an optimization process based on a surrogate model,which combines the class-shape transformation method(CST),the Latin hypercube sampling(LHS) method,the light gradient-boosting machine algorithm(LightGBM),and a genetic algorithm(GA) to optimize a high-subsonic compressor *** surrogate model is verified to be accurate and can be used in the optimization *** accuracy of the GA is higher than the other algorithms under common test *** optimization results are verified by numerical simulation,and the flow differences before and after optimization are compared,especially the flow within the boundary *** changing the blade shape,the optimization process adjusts the loading distribution to delay the transition of the optimized blade on the suction surface,which changes the turbulent reattachment in the laminar separation bubble(LSB) into laminar ***,the mixing loss induced by the turbulent reattachment of the LSB and the wake loss of turbulent separation at the trailing edge are significantly reduced,and the performance of the compressor profile is finally *** addition,turbulent separation of the optimized profile is delayed reducing the range of the wake region on the suction *** this optimization process,the reduction of total pressure loss coefficient at Re of 2.5×10～5,3.5×10～5,and 4.5×10～5 are 16.32%,20.76%,and 22.16%,respectively.

关键词： Reynolds number

Numerical Study of Flow and Heat Transfer Characteristics of Shell-and-Tube Molten Salt Electric Heater with Circularly Perforated Baffles

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Journal of Thermal Science 2025年第1期34卷 24-33页

作者： LIN Yongjie zhang Cancan WU Yuting zhang Yi LU Yuanwei Key Laboratory of Heat Transfer and Energy Conversion National User-Side Energy Storage Innovation Research and Development CenterBeijing University of Technology

Numerical simulations of the flow and heat transfer characteristics of four shell-and-tube molten salt electric heaters with different perforation rates was ***-and-tube electric heaters have the same geometry and tube arrangement,and all of them use single segmental baffles,but there exist four different baffle openings（φ）,i.e.,0%,2.52%,4.06%,and 6.31%.The results indicated that the reasonable baffle opening could significantly reduce the shell-side pressure drop,effectively decreasing the shell-side flow dead zone *** can eliminate the local high-temperature phenomenon on the surface of electric heating tubes,but the heat transfer coefficient is slightly *** perforated schemes significantly reduce shell-side pressure drop compared to the baseline solution without open *** particular,the φ=6.31% scheme exhibits the optimal performance among all the schemes,with a maximum reduction of up to 50.50% in shell-side pressure drop relative to the unopened holes *** heat transfer coefficient is the highest for φ=0%,exhibiting a range of5.26% to 5.73%,5.14% to 5.99%,and 7.31% to 8.54% higher than φ=2.52%,4.06%,and 6.31%,respectively,within the calculated *** composite index h/（Δp）1/3was higher for all open-hole solutions than that for the unopened-hole *** best overall performance was for φ=6.31%,which improved the composite index by15.29% to 17.18% over the unopened-hole solution.

关键词： molten salt electric heater perforated baffles heat transfer

A Lightweight Multiscale Feature Fusion Network for Solar Cell Defect Detection

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Computers, Materials & Continua 2025年第1期82卷 521-542页

作者： Xiaoyun Chen Lanyao zhang Xiaoling Chen Yigang Cen Linna zhang Fugui zhang School of Mechanical Engineering Guizhou UniversityGuiyang550025China School of Computer Science and Technology Beijing Jiaotong UniversityBeijing100044China

Solar cell defect detection is crucial for quality inspection in photovoltaic power generation *** the production process,defect samples occur infrequently and exhibit random shapes and sizes,which makes it challenging to collect defective ***,the complex surface background of polysilicon cell wafers complicates the accurate identification and localization of defective *** paper proposes a novel Lightweight Multiscale Feature Fusion network(LMFF)to address these *** network comprises a feature extraction network,a multi-scale feature fusion module(MFF),and a segmentation ***,a feature extraction network is proposed to obtain multi-scale feature outputs,and a multi-scale feature fusion module(MFF)is used to fuse multi-scale feature information *** order to capture finer-grained multi-scale information from the fusion features,we propose a multi-scale attention module(MSA)in the segmentation network to enhance the network’s ability for small target ***,depthwise separable convolutions are introduced to construct depthwise separable residual blocks(DSR)to reduce the model’s parameter ***,to validate the proposed method’s defect segmentation and localization performance,we constructed three solar cell defect detection datasets:SolarCells,SolarCells-S,and *** and SolarCells-S are monocrystalline silicon datasets,and PVEL-S is a polycrystalline silicon *** results show that the IOU of our method on these three datasets can reach 68.5%,51.0%,and 92.7%,respectively,and the F1-Score can reach 81.3%,67.5%,and 96.2%,respectively,which surpasses other commonly usedmethods and verifies the effectiveness of our LMFF network.

关键词： Defect segmentation multi-scale feature fusion multi-scale attention depthwise separable residual block

Bilevel Optimal Scheduling of Island Integrated Energy System Considering Multifactor Pricing

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Energy Engineering 2025年第1期122卷 349-378页

作者： Xin zhang Mingming Yao Daiwen He Jihong zhang Peihong Yang Xiaoming zhang School of Automation and Electrical Engineering Inner Mongolia University of Science and TechnologyBaotou014010China

In this paper,a bilevel optimization model of an integrated energy operator(IEO)–load aggregator(LA)is constructed to address the coordinate optimization challenge of multiple stakeholder island integrated energy system(IIES).The upper level represents the integrated energy operator,and the lower level is the electricity-heatgas load *** to the benefit conflict between the upper and lower levels of the IIES,a dynamic pricing mechanism for coordinating the interests of the upper and lower levels is proposed,combined with factors such as the carbon emissions of the IIES,as well as the lower load interruption *** price of selling energy can be dynamically adjusted to the lower LA in the mechanism,according to the information on carbon emissions and load interruption *** benefits and win-win situations are achieved between the upper and lower ***,CPLEX is used to iteratively solve the bilevel optimization *** optimal solution is selected according to the joint optimal discrimination *** results indicate that the sourceload coordinate operation can reduce the upper and lower operation *** the proposed pricingmechanism,the carbon emissions and load interruption power of IEO-LA are reduced by 9.78%and 70.19%,respectively,and the capture power of the carbon capture equipment is improved by 36.24%.The validity of the proposed model and method is verified.

关键词： Bilevel optimal scheduling load aggregator integrated energy operator carbon emission dynamic pricing mechanism

Modulation of the octahedral structure and potential superconductivity of La3Ni2O7 through strain engineering

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： Zihao Huo zhihui Luo Peng zhang Aiqin Yang Zhengtao Liu Xiangru Tao Zihan zhang Shumin guo Qiwen Jiang Wenxuan Chen Dao-Xin Yao Defang Duan Tian Cui Key Laboratory of Material Simulation Methods & Software of Ministry of Education State Key Laboratory of Superhard Materials College of Physics Jilin University Center for Neutron Science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices State Key Laboratory of Optoelectronic Materials and Technologies School of Physics Sun Yat-sen University MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter Shaanxi Province Key Laboratory of Advanced Functional Materials and Mesoscopic Physics School of Physics Xi'an Jiaotong University Institute of High Pressure Physics School of Physical Science and Technology Ningbo University

The recent transport measurements of La3Ni2O7uncovered a“right-triangle”shape of the superconducting dome in the pressure-temperature （P-T） phase *** by this,we perform theoretical first-principles studies of La3Ni2O7with the pressure ranging from 0 to 100 ***,we reveal a pressure dependence of the Ni-d2zelectron density at the Fermi energy (nE Fz) that highly coincides with such *** this basis,we further explore the electronic structure under uniaxial *** tracking the stress response of nE Fz,we propose that superconductivity can be achieved by applying only～2 GPa of compression along the c *** idea is further exemplified from the perspectives of lattice distortion,band structure,Fermi surface and superconducting phase *** also discuss the possible charge modulation under the stress and provide an insight into the relation between nE Fzand the superconducting Tcin *** study provides new routes to the search of high-Tcsuperconductors in future experiments.

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Propagating subduction initiation of the Caroline Plate at the Mussau Trench

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Science China Earth Sciences 2025年第1期68卷 253-269页

作者： Chun-Feng LI Yongkang DENG Tao WU Dongdong DONG guoliang zhang Jiazheng zhang Yutao LIU Yaqing LI Fugui TANG Lulu zhang Department of Marine Sciences Zhejiang University Laboratory of Marine Mineral Resources Laoshan Laboratory Key Lab of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Key Lab of Ocean and Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Science & Technology on Integrated Information System Lab Institute of Software Chinese Academy of Sciences

New seismic imaging from the Mussau Trench confirms that, under horizontal compression on an oceanic plate boundary, it is within the young and weak oceanic plate that a trench will develop, and it is the young plate, not so long after its birth, that starts to subduct toward the old plate. The Mesozoic Pacific Plate cannot easily bend, under the joint horizontal compression and vertical gravity pull, even with a pre-existing weak zone in place and with a large age offset across the plate boundary. The bending of the Caroline Plate near the northern end of the Mussau Trench started only after a long-time span of trench migration, and/or after a prolonged transition from initial compression to trench development. Highly contrasting trench deformation and sedimentary accretion between two parallel seismic sections support an evident migration of underthrusting or significant longitudinal heterogeneity along the trench. The swift transition from underthrusting to non-thrusting can be explained by a counter-clockwise rotation of the Caroline Plate. That miniature accretionary wedges develop even before the subduction initiates imply strong compression and uplifting before the underthrusting can kick-start. Rotation of the Caroline Plate have been halted as the Mussau Trench is seismically rather quiet and the Lyra Trough to the east shows relaxational extension.

关键词： Mussau Trench Subduction initiation Seismic reflection Caroline Plate

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基于演化模式特征的克隆代码分类

计算机工程与设计 2017年第8期38卷 2121-2126页

作者：王春晖张久杰刘志国张丽萍刘东升内蒙古师范大学计算机与信息工程学院内蒙古呼和浩特010022 内蒙古科技大学包头师范学院信息科学与技术学院内蒙古包头014000

克隆代码稳定性与它在多版本演化过程中的变化模式相关,综合这些变化模式并构建自动分类模型,实现克隆代码稳定与易变的特征标注,便于开展克隆分类方面的研究。从克隆演变、克隆规模变化与克隆修改3个维度将克隆演化分为12种演化模式,... 详细信息

克隆代码稳定性与它在多版本演化过程中的变化模式相关,综合这些变化模式并构建自动分类模型,实现克隆代码稳定与易变的特征标注,便于开展克隆分类方面的研究。从克隆演变、克隆规模变化与克隆修改3个维度将克隆演化分为12种演化模式,通过版本间克隆的差异分析识别这12种模式,记录变化参数,使用克隆聚类特征模型计算每个克隆实例的特征向量,用聚类算法实现克隆稳定性分类。对两款软件进行实验分析,分析结果表明,基于该方法可以得到关于克隆稳定性的有效分类数据集。

关键词：克隆代码克隆演化模式特征克隆分类克隆分析克隆管理

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HNRNPC as a pan-cancer biomarker and therapeutic target involved in tumor progression and immune regulation

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Oncology Research 2025年第1期33卷 83-102页

作者： YUEZHOU zhang ZHAO zhang JINXIN DONG CHANGAN LIU Department of Hepatobiliary Surgery The Second Affiliated Hospital of Chongqing Medical UniversityChongqing400016China Department of Hepatobiliary Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing400016China

Background:Aberrant expression of RNA-binding proteins(RBPs)has been linked to a variety of diseases,including hematological disorders,cardiovascular diseases,and multiple types of *** nuclear ribonucleoprotein C(HNRNPC),a member belonging to the heterogeneous nuclear ribonucleoprotein(hnRNP)family,plays a pivotal role in nucleic acid *** studies have underscored the significance of HNRNPC in tumorigenesis;however,its specific role in malignant tumor progression remains inadequately ***:We leveraged publicly available databases,including The Cancer Genome Atlas(TCGA),to explore the potential involvement of HNRNPC across various ***,we performed experimental validation studies focused on liver ***:Our analysis revealed that HNRNPC is overexpressed in a wide range of common malignancies,including liver and lung cancers,and is strongly linked to unfavorable ***,HNRNPC was observed to be closely linked to tumor *** immune checkpoint analysis and immune cell infiltration assessment,HNRNPC emerged as a potential target for modulating tumor ***,silencing of HNRNPC markedly inhibited the proliferation,metastasis,and infiltration of liver cancer ***:In summary,our findings highlight HNRNPC as a prognostic marker in various cancers,including liver cancer,and suggest its involvement in shaping the tumor immune *** insights offer potential avenues for improving clinical outcomes in tumors with elevated HNRNPC expression,particularly through immunotherapeutic strategies.

关键词： Heterogeneous nuclear ribonucleoprotein C(HNRNPC) Pan-cancer analysis Tumor immunity Prognostic biomarker Immunotherapeutic target Hepatocellular carcinoma