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An anti-collision algorithm for robotic search-and-rescue tasks in unknown dynamic environments

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 569-584页

作者： Yang CHEN Dianxi shi Huanhuan YANG Tongyue LI Zhen WANG School of Computer Science Peking UniversityBeijing 100871China Tianjin Artificial Intelligence Innovation Center Tianjin 300457China Intelligent Game and Decision Lab Beijing 100071China College of Computer National University of Defense TechnologyChangsha 410073China

This paper deals with the search-and-rescue tasks of a mobile robot with multiple interesting targets in an unknown dynamic *** problem is challenging because the mobile robot needs to search for multiple targets while avoiding obstacles *** ensure that the mobile robot avoids obstacles properly,we propose a mixed-strategy Nash equilibrium based Dyna-Q(MNDQ)***,a multi-objective layered structure is introduced to simplify the representation of multiple objectives and reduce computational *** structure divides the overall task into subtasks,including searching for targets and avoiding ***,a risk-monitoring mechanism is proposed based on the relative positions of dynamic *** mechanism helps the robot avoid potential collisions and unnecessary ***,to improve sampling efficiency,MNDQ is presented,which combines Dyna-Q and mixed-strategy Nash *** using mixed-strategy Nash equilibrium,the agent makes decisions in the form of probabilities,maximizing the expected rewards and improving the overall performance of the Dyna-Q ***,a series of simulations are conducted to verify the effectiveness of the proposed *** results show that MNDQ performs well and exhibits robustness,providing a competitive solution for future autonomous robot navigation tasks.

关键词： Search and rescue Reinforcement learning Game theory Collision avoidance Decision-making

Infrared radiation characteristics of dagger-type hypersonic missile

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Chinese Journal of Aeronautics 2024年第4期37卷 137-150页

作者： Xubo DU Qingzhen YANG Haoqi YANG Jin BAI Yongqiang shi School of Power and Energy Northwestern Polytechnical UniversityXi’an 710129China

Hypersonic vehicles emit strong infrared radiation from their high-temperature exhaust plume and body, which is critical for infrared early warning, tracking, and guidance. In this work, a comprehensive analysis is conducted on the factors involved in air dissociation reaction within the shock layer of hypersonic missile heads, as well as the multi-component afterburning effect of the exhaust plume. A novel Reverse Monte Carlo Method(RMCM) is proposed for infrared radiation calculation, which utilizes two-dimensional Low-Discrepancy Sequences(LDS) to improve computational accuracy. The numerical calculations for a dagger-type missile show that afterburning reactions increase the temperature on the centerline of the outlet exhaust plume by about 1000 K. The total infrared radiation intensity of the missile is the highest in the 1–3 μm band, with the hightemperature wall of the nozzle being the primary source of solid radiation, and gas radiation primarily coming from H_(2)O. The radiation intensity of the missile exhaust plume in the 3–5 μm band is the highest, with radiation sources primarily coming from CO_(2), CO, and HCl. Afterburning reactions of the exhaust plume increase the total infrared radiation intensity of the missile by about 0.7times. These results can provide reference for the detection and guidance of hypersonic missiles.

关键词： Hypersonic vehicles Infrared radiation Monte Carlo methods Low-discrepancy sequences Exhaust plume Afterburning

Oxygen vacancy boosting Fenton reaction in bone scaffold towards fighting bacterial infection

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International Journal of Extreme Manufacturing 2024年第1期6卷 296-311页

作者： Cijun Shuai Xiaoxin shi Feng Yang Haifeng Tian Pei Feng State Key Laboratory of Precision Manufacturing for Extreme Service Performance College of Mechanical and Electrical EngineeringCentral South UniversityChangsha 410083People’s Republic of China Institute of Additive Manufacturing Jiangxi University of Science and TechnologyNanchang 330013People’s Republic of China College of Mechanical Engineering Xinjiang UniversityUrumqi 830017People’s Republic of China

Bacterial infection is a major issue after artificial bone transplantation due to the absence of antibacterial function of bone scaffold,which seriously causes the transplant failure and even amputation in severe *** this study,oxygen vacancy(OV)defects Fe-doped Ti O2(OV-FeTiO2)nanoparticles were synthesized by nano TiO2and Fe3O4via high-energy ball milling,which was then incorporated into polycaprolactone/polyglycolic acid(PCLGA)biodegradable polymer matrix to construct composite bone scaffold with good antibacterial activities by selective laser *** results indicated that OV defects were introduced into the core/shell-structured OV-FeTiO2nanoparticles through multiple welding and breaking during the high-energy ball milling,which facilitated the adsorption of hydrogen peroxide(H2O2)in the bacterial infection microenvironment at the bone transplant *** accumulated H2O2could amplify the Fenton reaction efficiency to induce more hydroxyl radicals(·OH),thereby resulting in more bacterial deaths through·OH-mediated oxidative *** antibacterial strategy had more effective broad-spectrum antibacterial properties against Gram-negative Escherichia coli(***)and Gram-positive Staphylococcus aureus(***).In addition,the PCLGA/OV-FeTiO2scaffold possessed mechanical properties that match those of human cancellous bone and good biocompatibility including cell attachment,proliferation and osteogenic differentiation.

关键词： bacterial infection bone scaffold selective laser sintering Fenton reaction antibacterial properties

Review on the design of high-strength and hydrogen-embrittlement-resistant steels

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1572-1589页

作者： Zhiyu Du Rongjian shi Xingyu Peng Kewei Gao Xiaolu Pang Beijing Advanced Innovation Center for Materials Genome Engineering School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China Institute for Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110010China

Given the carbon peak and carbon neutrality era,there is an urgent need to develop high-strength steel with remarkable hydrogen embrittlement *** is crucial in enhancing toughness and ensuring the utilization of hydrogen in emerging iron and steel ***,the pursuit of enhanced metallic materials presents a cross-disciplinary scientific and engineering *** high-strength,toughened steel with both enhanced strength and hydrogen embrittlement(HE)resistance holds significant theoretical and practical *** ensures secure hydrogen utilization and further carbon neutrality objectives within the iron and steel *** on the design principles of high-strength steel HE resistance,this review provides a comprehensive overview of research on designing surface HE resistance and employing nanosized precipitates as intragranular hydrogen *** also proposes feasible recommendations and prospects for designing high-strength steel with enhanced HE resistance.

关键词： hydrogen embrittlement surface design hydrogen traps nanosized precipitates

103 GHz germanium-on-silicon photodiode enabled by an optimized U-shaped electrode

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Photonics Research 2024年第1期12卷 1-6页

作者： Yang shi Xiang Li Mingjie Zou Yu Yu Xinliang Zhang Wuhan National Laboratory for Optoelectronics&School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China School of Mechanical Engineering and Electronic Information China University of GeosciencesWuhan 430074China Optics Valley Laboratory Wuhan 430074China Xidian University Xi’an 710126China

High-performance germanium photodiodes are crucial components in silicon photonic integrated circuits for large-capacity data ***,the bandwidths of most germanium photodiodes are limited by the intractable resistance–capacitance parasitic ***,we introduce a unique U-shaped electrode to alleviate this issue,reducing the parasitic effect by 36%without compromising any other ***,a large bandwidth of 103 GHz,an optical responsivity of 0.95 A/W at 1550 nm,and a dark current as low as 1.3 nA are achieved,leading to a record high specific *** is the first breakthrough to 100 GHz bandwidth among all vertical germanium photodiodes,to the best of our *** eye diagrams of 120 Gb/s on-off keying and 200 Gb/s four-level pulse amplitude signals are well *** work provides a promising solution for chip-based ultra-fast photodetection.

关键词： Gb/s shaped electrode

Promoted surface charge density from interlayer Zn–N_(4) configuration in carbon nitride for enhanced CO_(2) photoreduction

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Nano Research 2024年第4期17卷 2400-2409页

作者： Xianjin shi Yu Huang Gangqiang Zhu Wei Peng Meijuan Chen State Key Laboratory of Loess and Quaternary Geology(SKLLQG) Key Laboratory of Aerosol Chemistry and PhysicsInstitute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Center of Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi’an 710061China University of Chinese Academy of Sciences Beijing 100049China School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710062China School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710049China

The solar-driven reduction of CO_(2) into valuable products is a promising method to alleviate global environmental problems and energy ***,the low surface charge density limits the photocatalytic conversion performance of CO_(2).Herein,a polymeric carbon nitride(PCN)photocatalyst with Zn single atoms(Zn1/CN)was designed and synthesized for CO_(2) *** results of the CO_(2) photoreduction studies show that the CO and CH_(4) yields of Zn1/CN increased fivefold,reaching 76.9 and 22.9μmol/(g·h),respectively,in contrast to the unmodified ***+plasma-etched X-ray photoelectron spectroscopy and synchrotron radiation-based X-ray absorption fine structure results reveal that Zn single atom is mainly present in the interlayer space of PCN in the Zn–N_(4) *** characterizations indicate that the interlayer Zn–N_(4) configuration can amplify light absorption and establish an interlayer charge transfer ***-assisted Kelvin probe force microscopy confirms that more photogenerated electrons are delivered to the catalyst surface through interlayer Zn–N_(4) configuration,which increases its surface charge ***,in-situ infrared spectroscopy combined with density functional theory calculation reveals that promoted surface charge density accelerates key intermediates(*COOH)conversion,thus achieving efficient CO_(2) *** work elucidates the role of internal single atoms in catalytic surface reactions,which provides important implications for the design of single-atom catalysts.

关键词： single-atom catalysts photocatalytic CO_(2)reduction interlayer modification charge transfer dynamics surface charge density

Role of oncogenic long noncoding RNA KCNQ1OT1 in colon cancer

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Oncology Research 2024年第3期32卷 585-596页

作者： GANG LIU LEI shi BIN WANG ZEHUI WU HAIYUAN ZHAO TIANYU ZHAO LIANGHUI shi Department of Gastrointestinal Surgery First ffiliated Hospital of Wannan Medical CollegeWuhu241001China Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences Stomatological Hospital of Chongqing Medical UniversityChongqing401147China

The role of lncRNA KCNQ1 opposite strand/antisense transcript 1(KCNQ1OT1)in colon cancer involves various tumorigenic processes and has been studed ***,the mechanism by which it promotes colon cancer remains *** vector pSEB61 was retroftted in established HCT116 siKCN and SW480-siKCN cells to silence KCNQ1 *** proliferation was measured using CCK8 assay,and flow cytometry(FCM)detected cell cydle *** sequencing(RNA Seq)analysis showed differentially expressed genes(DEGs).Gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses were carried out to analyze enriched functions and signaling ***-qPCR,immunofluorescence,and western blotting were carried out to validate downstream gene *** effects of tumorigenesis were evaluated in BALB/c nude mice by tumor *** data revealed that the silencing of KONQ1OT1 in HCT116 and SW480 cells slowed cell growth and decreased the number of cells in the G2/M ***-Seq analysis showed the data of DEGs enriched in various GO and KEGG pathways such as DNA replication and cell *** qPCR,immunofluorescence,and western blotting confirmed downstream CCNE2 and PCNA gene ***116 siKCN cells signifcantly suppressed tumorigenesis in BALB/c nude *** study suggests that lncRNA KCNQ1OT1 may provide a promising therapeutic strategy for colon cancer.

关键词： lncRNA KCNQ1OT1 Colon cancer HCT116 cells Tumorigenesis

Experimental study on the size effect on the equation of state of concretes under shock loading

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Defence Technology（防务技术） 2024年第3期33卷 160-167页

作者： Mei Li Jian Cui Yanchao shi Baijian Tang Xin Chen Key Laboratory of Coast Civil Structural Safety of the Ministry of Education Tianjin UniversityTianjin 300072China School of Civil Engineering Suzhou University of Science and Technology1701 Binhe RoadSuzhou 215011JiangsuChina School of Civil Engineering Tianjin UniversityTianjin 300072China

Adopting the classical theory of hydrocodes,the constitutive relations of concretes are separated into an equation of state(EoS)which describes the volumetric behavior of concrete material and a strength model which depicts the shear properties of *** experiments on the EoS of concrete is always challenging due to the technical difficulties and equipment limitations,especially for the specimen size effect on the *** some researchers investigate the shock properties of concretes by fly-plate impact tests,the specimens used in their tests are usually in one *** this paper,the fly-plate impact tests on concrete specimens with different sizes are performed to investigate the size effect on the shock properties of concrete *** mechanical background of the size effect on the shock properties are revealed,which is related to the lateral rarefaction effect and the deviatoric stress produced in the *** to the tests results,the modified EoS considering the size effect on the shock properties of concrete are proposed,which the bulk modulus of concrete is unpredicted by up to 20% if size effects are not accounted for.

关键词： Concrete Equation of state Size effect Shock wave Fly-plate impact test

Application of immune checkpoint inhibitors and microsatellite instability in gastric cancer

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World Journal of Gastroenterology 2024年第21期30卷 2734-2739页

作者： shi-Yan Yan Jian-Gao Fan Department of Gastroenterology Xinhua HospitalShanghai Jiaotong University School of MedicineShanghai 200092China

In this editorial we comment on the article by Li published in the recent issue of the World Journal of *** focus specifically on the application of immune checkpoint inhibitors(ICIs)and microsatellite instability(MSI)in gastric cancer(GC).The four pillars of GC management have long been considered,including surgery,chemotherapy,radiotherapy and targeted ***,immunotherapy has recently emerged as a“fifth pillar”,and its use is rapidly *** are four principal strategies for tumor immunotherapy:ICIs,tumor vaccines,adoptive immunotherapy and nonspecific *** them,ICIs are the most advanced and widespread type of cancer immunotherapy for *** breakthrough results for ICIs have paved the way to a new era of cancer *** particular,inhibition of the PD-1/PD-L1 axis with ICIs,including nivolumab and pembrolizumab,has emerged as a novel treatment strategy for advanced ***,these therapies are sometimes associated with often subtle,potentially fatal immune-related adverse events(irAEs),including dermatitis,diarrhea,colitis,endocrinopathy,hepatotoxicity,neuropathy and *** must be aware of these irAEs and improve the detection of these processes to prevent inappropriate discharges,emergency department revisits,and downstream *** studies have revealed that MSI-high or mismatch-repair-deficient tumors,regardless of their primary site,have a promising response to ***,it is important to detect MSI before applying ICIs for treatment of GC.

关键词： Gastric cancer Immune checkpoint inhibitors Microsatellite instability Immunotherapy Immune-related adverse events