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Inherently Sinusoidal Single-phase Voltage Source Inverter Based on Modified Cuk Cell

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Chinese Journal of Electrical engineering 2024年第1期10卷 114-123页

作者： Misbahul Munir Wisyahyadi Arwindra Rizqiawan Jihad Furqani school of Electrical engineering and informatics Bandung Institute of TechnologyBandung 40132Indonesia

Renewable energy has become important for electricity generation because of the high air pollution associated with conventional fossil-based energy *** fossil-based power plants are gradually transitioning by incorporating renewable energy sources,such as photovoltaic(PV)*** a PV system,an inverter converts DC power from solar panels to AC power required to serve common electrical loads.A conventional H-bridge inverter topology has several disadvantages,such as the voltage being not sinusoidal,switching the DC voltage and high common-mode *** common-mode voltage can cause a large leaked capacitive current,which can result in undesirable operation in solar power applications.A common solution to this problem is the addition of a large filter to the input or output of an *** inherent sinusoidal voltage source inverter based on a modified Cuk converter as its basic cell,which simultaneously generates a sinusoidal output voltage and a lower common-mode voltage,is *** proposed topology does not require additional input or output *** expressions are derived to confirm the operation of the proposed *** results confirm the mathematical analysis.A laboratory-scale experiment is performed to verify the proposed inverter.

关键词： Voltage source inverter common-mode voltage capacitive current modified Cuk converter and sinusoidal waveform

Vehicle Head and Tail Recognition Algorithm for Lightweight DCDSNet

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Computers, Materials & Continua 2024年第9期80卷 4451-4473页

作者： Chao Wang Kaijie Zhang Xiaoyong Yu Dejun Li Wei Xie Xinqiao Wang school of informatics and engineering Suzhou UniversitySuzhou234000China school of informatics and engineering Suzhou Vocational College of Civil AviationSuzhou234122China Institute of Machine Learning and Systems Biology School of Electronics and Information EngineeringTongji UniversityShanghai201804China

In the model of the vehicle recognition algorithm implemented by the convolutional neural network,the model needs to compute and store a lot of *** many parameters occupy a lot of computational resources making it difficult to run on computers with poor ***,obtaining more efficient feature information of target image or video with better accuracy on computers with limited arithmetic power becomes the main goal of this *** this paper,a lightweight densely connected,and deeply separable convolutional network(DCDSNet)algorithmis proposed to achieve this *** Geometry Group(VGG)model is improved by utilizing the convolution instead of the fully connected module,the deeply separable convolution module,and the densely connected network module,with the first two modules reducing the parameters and the third module allowing the algorithm to have more features in a limited number of *** algorithm achieves better results in the mine vehicle recognition *** show that the recognition accuracy is improved by 4.41% compared to VGG19 and the amount of parameters is reduced by 71% compared to VGG19.

关键词： VGGNet vehicle head and tail recognition densely connected depthwise separable convolutional

Ripple Knowledge Graph Convolutional Networks for Recommendation Systems

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Machine Intelligence Research 2024年第3期21卷 481-494页

作者： Chen Li Yang Cao Ye Zhu Debo Cheng Chengyuan Li Yasuhiko Morimoto graduate school of informatics Nagoya UniversityChikusaNagoya 464-8602Japan Centre for Cyber Resilience and Trust Deakin UniversityBurwood 3125Australia Science TechnologyEngineering and Mathematics(STEM)University of South AustraliaAdelaide 5000Australia graduate school of engineering Hiroshima UniversityHigashi-hiroshima 10587Japan

Using knowledge graphs to assist deep learning models in making recommendation decisions has recently been proven to effectively improve the model′s interpretability and *** paper introduces an end-to-end deep learning model,named representation-enhanced knowledge graph convolutional networks(RKGCN),which dynamically analyses each user′s preferences and makes a recommendation of suitable *** combines knowledge graphs on both the item side and user side to enrich their representations to maximize the utilization of the abundant information in knowledge *** is able to offer more personalized and relevant recommendations in three different *** experimental results show the superior effectiveness of our model over 5 baseline models on three real-world datasets including movies,books,and music.

关键词： Deep learning recommendation systems knowledge graph graph convolutional networks(GCNs) graph neural networks(GNNs)

Non-Kramers doublet ground state in a quaternary cubic compound PrRu_(2)In_(2)Zn_(18) investigated by ultrasonic measurements

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Chinese Physics B 2024年第6期33卷 405-411页

作者：张化远 Kazuhei Wakiya Mitsuteru Nakamura Masahito Yoshizawa Yoshiki Nakanish graduate school of Science and engineering Iwate UniversityMorioka 020-8551Japan

We performed ultrasonic measurements on a quaternary cubic compound PrRu_(2)In_(2)Zn_(18) to explore the ground state properties derived from non-Kramers Γ_(3) doublet of Pr^(3+).PrRu_(2)In_(2)Zn_(18) is a quaternary derivative of the ternary compound PrRu_(2)Zn_(20) that exhibits a structural phase transition at T_S=138 *** PrRu_(2)In_(2)Zn_(18),the Zn atoms at the 16c site in PrRu_(2)Zn_(20) are selectively replaced by In atoms.A monotonic increase was observed in the temperature dependence of elastic constants C_L=(C_(11)+2C_(12)+4C_(44))/3 and C_(T)=(C_(11)-C_(12)+C_(44))/3 in the temperature range around T_(S) to which an elastic softening was observed in(C_(11)-C_(12))/2 for PrRu_(2)Zn_(20).The disappearance of the softening indicates that the structural transition in PrRu_(2)Zn_(20) is suppressed by the substitution of Zn ions by In ones with a larger ionic ***,the C_(T) of PrRu_(2)In_(2)Zn_(18) exhibits a precursor Curie-type elastic softening toward low temperatures being responsible for the non-Kramers Γ_(3) ground *** discuss the ground state and the evolution of the elastic properties of the different single-crystal samples of PrRu_(2)In_(2)Zn_(18) grown under different conditions.

关键词： ultrasonic measurements non-Kramers doublet structural phase transition crystalline electric field effect

Modifying effects and mechanisms of superfine stainless wires on microstructures and mechanical properties of ultra-high performance seawater sea-sand concrete

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Science China Technological Sciences 2024年第10期67卷 3205-3220页

作者： YU Feng DONG SuFen ASHOUR Ashraf DING SiQi HAN BaoGuo school of Infrastructure engineering Dalian University of Technology Faculty of engineering & informatics University of Bradford Department of Civil and Environmental engineering The Hong Kong Polytechnic University

Ultra-high-performance seawater sea-sand concrete（UHPSSC） presents a prospective solution to address the natural resource shortage in marine infrastructure construction. To eliminate the corrosion risk of steel fibers and broaden the applicability of UHPSSC, this study investigates the mechanical properties and free chloride ion content as well as microstructures of UHPSSC reinforced with superfine stainless wires（SSWs） under natural curing. The results indicate that 1.5% SSWs can remarkably improve the flexural strength and toughness of UHPSSC by 127% and 1724%, respectively, and mitigate the long-term strength degradation of UHPSSC. The strong interfacial bond between SSW and UHPSSC improves the compactness of UHPSSC, thus reducing the growth space for Ca（OH）2crystals and swelling hydration products generated by sulfate and magnesium ions. This can be supported by the observed reduction in the Ca/Si ratio of C–S–H gels, CH crystal orientation index, and ***, through mechanisms such as pull-out, rupture, overlapping network, and internal anchor interface, SSWs effectively prevent microcrack growth and propagation, transforming single long-connected microcracks into multiple-emission microcracks centered on SSW. Additionally, the free chloride ion content of the composites at 28 and 180 d meets the ACI 318-19 standard requirements for concrete exposed to seawater. This compliance is attributed to the chloride immobilization facilitated by Friedel's salt and C–S–H gels within the interfaces around SSWs and sea-sand. Consequently, SSWs-reinforced UHPSSC exhibits considerable potential for applications in sustainable marine infrastructures, demanding long-term mechanical properties and high durability.

关键词： ultra-high performance seawater sea-sand concrete superfine stainless wire mechanical properties chloride ion content microstructure

Factors Impacting Participatory Post‑Disaster Relocation and Housing Reconstruction:The Case of Tsholotsho District,Zimbabwe

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International Journal of Disaster Risk Science 2024年第1期15卷 58-72页

作者： Nombulelo Kitsepile Ngulube Hirokazu Tatano Subhajyoti Samaddar Department of Social informatics Graduate School of InformaticsKyoto UniversityKyoto 606-8507Japan Disaster Prevention Research Institute(DPRI) Kyoto UniversityKyoto 611-0011Japan

Relocation is not typically considered the best planning option for post-disaster reconstruction and rehabilitation,but it may be necessary if the site has suffered severe damage or is at imminent *** is a growing recognition that strong community participation is necessary in the post-disaster relocation decision-making process since relocation can have detrimental effects on a community’s livelihood,cultural system,and way of life,among ***,the realization of this still needs to be *** of yet,few studies have examined a comprehensive account of meaningful community engagement in post-disaster relocation and reconstruction,particularly in developing *** study investigated what factors influenced local communities’ participation in post-disaster relocation and reconstruction works after the 2017Cyclone Dineo flood disaster in the Tsholotsho District of *** research methods such as face-to-face interviews,observations,and focus groups were used to collect qualitative data from a purposive sample of 25 community members and 6 *** empirical investigation showed that despite the fact that the relocation project was conceived as a community-centered project,there was no meaningful community engagement,due to the absence of a participatory framework or planning guidelines for stakeholder engagement,as well as the lack of political willingness among government *** study concluded that the lack of community involvement led to local communities abandoning the reconstruction sites because relocation projects failed to accommodate the cultural beliefs,place attachments,and livelihood concerns of local *** study suggested that it is imperative to enhance the awareness of government officials and other stakeholders about the importance of community participation for the effective implementation of post-disaster relocation *** community participation can also provide avenues fo

关键词： Community rehabilitation Housing reconstruction-Participatory relocation Zimbabwe

Dynamics of 2×2 matrix non-Hermitian quantum systems on Bloch sphere

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Communications in Theoretical Physics 2024年第4期76卷 66-71页

作者： Libin Fu graduate school of China Academy of engineering Physics Beijing 100193China

By casting evolution to the Bloch sphere, the dynamics of 2 × 2 matrix non-Hermitian systems are investigated in detail. This investigation reveals that there are four kinds of dynamical modes for such systems. The different modes are classified by different kinds of fixed points, namely,the elliptic point, spiral point, critical node, and degenerate point. The Hermitian systems and the unbroken PT non-Hermitian cases belong to the category with elliptic points. The degenerate point just corresponds to the systems with exceptional point(EP). The topological properties of the fixed point are also discussed. It is interesting that the topological charge for the degenerate point is two, while the others are one.

关键词： non-Hermitian quantum system two-level system dynamics on the Bloch sphere PT-symmetry fixed points

Few-shot incremental radar target recognition framework based on scattering-topology properties

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Chinese Journal of Aeronautics 2024年第8期37卷 246-260页

作者： Chenxuan LI Weigang ZHU Bakun ZHU Yonggang LI graduate school Space Engineering UniversityBeijing 101400China Department of Electronic and Optical engineering Space Engineering UniversityBeijing 101400China

The continuous emergence of new targets in open scenarios leads to a substantial decrease in the performance of Inverse Synthetic Aperture Radar(ISAR)recognition ***,data scarcity further exacerbates the challenge of identifying new classes of ISAR *** this paper,a few-shot incremental target recognition framework based on Scattering-Topology Properties(STPIL)is ***,STPIL extracts scattering-topology properties of ISAR targets as recognition ***,the pseudo-incremental training strategy effectively alleviates the algorithm’s forgetting of old knowledge,and improves compatibility with new ***,a feature embedding network,with few parameters,is designed based on the graph neural *** embedding network is highly adaptable to changes in data ***,STPIL fully considers the joint distribution and marginal distribution in scattering features,and uses the Brownian distance metric module to make the scattering-topology features more *** results on both the simulation dataset and the public measured data indicate that STPIL can effectively balance new classes with old classes,and has superior performance to other advanced methods in the incremental recognition of targets.

关键词： Brownian distance metric Graph neural networks Incremental learning Inverse Synthetic Aperture Radar(ISAR) Scattering

Product Form Solution of a Queuing-Inventory System with Lost Sales and Server Vacation

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Journal of Systems Science & Complexity 2024年第2期37卷 729-758页

作者： YUE Dequan ZHANG Yuying XU Xiuli YUE Wuyi school of Science Yanshan UniversityQinhuangdao 066004China school of Economics and Management Yanshan UniversityQinhuangdao 066004China The Kyoto College of graduate Studies for informatics Kyoto City 606-8225Japan

In this study,the authors consider an M/M/1 queuing system with attached inventory under an(s,S)control *** server takes multiple vacations whenever the inventory is *** is assumed that the lead time and the vacation time follow exponential *** authors formulate the model as a quasi-birth-and-dearth(QBD)process and derive the stability condition of the ***,the stationary distribution in product form for the joint process of the queue length,the inventory level,and the server’s status is ***,the conditional distributions of the inventory level when the server is on and operational,and when it is off due to a vacation,are *** the stationary distribution,the authors obtain some performance measures of the *** authors investigate analytically the effect of the server’s vacation on the performance ***,several numerical examples are presented to investigate the effects of some parameters on the performance measures,the optimal policy,and the optimal cost.

关键词： Cost function multiple vacations product form solution queuing-inventory system (s S)control policy