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Joint Optimization of Resource Allocation and Trajectory Based on User Trajectory for UAV-Assisted Backscatter Communication System

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China Communications 2024年第2期21卷 197-209页

作者： Peizhong Xie Junjie Jiang Ting li Yin lu School of Communication and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Lab of Broadband Wireless Communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of EducationNanjing 210003China

The Backscatter communication has gained widespread attention from academia and industry in recent years. In this paper, A method of resource allocation and trajectory optimization is proposed for UAV-assisted backscatter communication based on user trajectory. This paper will establish an optimization problem of jointly optimizing the UAV trajectories, UAV transmission power and BD scheduling based on the large-scale channel state signals estimated in advance of the known user trajectories, taking into account the constraints of BD data and working energy consumption, to maximize the energy efficiency of the system. The problem is a non-convex optimization problem in fractional form, and there is nonlinear coupling between optimization *** iterative algorithm is proposed based on Dinkelbach algorithm, block coordinate descent method and continuous convex optimization technology. First, the objective function is converted into a non-fractional programming problem based on Dinkelbach method,and then the block coordinate descent method is used to decompose the original complex problem into three independent sub-problems. Finally, the successive convex approximation method is used to solve the trajectory optimization sub-problem. The simulation results show that the proposed scheme and algorithm have obvious energy efficiency gains compared with the comparison scheme.

关键词： energy efficiency joint optimization UAV-assisted backscatter communication user trajectory

Ultra-flexible all-in-one anti-freeze photothermally enhanced supercapacitors

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Nano Research 2024年第8期17卷 7221-7229页

作者： Yongxin lu Keke li Yan-Yan Song Zhida Gao Condense matter of physics College of ScienceNortheazistern UniversityShenyang 110004China

Wearable electronics powered by flexible energy storage devices have captured global *** low-temperature conditions,unfortunately,solidification of flexible hydrogel electrolyte and decreased pseudo-capacity of these devices largely hamper their practical *** this study,photothermally-active Prussian blue(PB)was introduced onto poly(3,4-ethylenedioxythiophene)/polyacrylamide(PEDOT/PAM)networks to address the challenges of electrolyte solidification and degraded pseudo-capacitance for flexible all-in-one device at low *** as-constructed PB/PEDOT/PAM hydrogel device delivers stable electrochemical performance and remarkable mechanical property with 1652%***,this hydrogel device well retains its flexibility in cold environment with a freezing point below−30℃.The incorporation of PB extends the voltage range to 1.5 V as a single device,thus significantly enhancing the electrochemical performance as an all-inone integrated *** from the outstanding photo-to-thermal conversion ability of embedded PB nanocubes,the temperature of the assembled all-in-one PB/PEDOT/PAM device increased from^(−2)0 to 17.7℃ after solar-light irradiation for only 5 ***,the degraded pseudo-capacitance was subsequently boosted to 287.1%of its original capacitance at−20℃.This study establishes a connection between flexible all-solid-state hydrogel devices and photothermally enhanced pseudocapacitors in freezing environments,thereby expanding the potential applications of multi-functional pseudo-capacitors.

关键词： all-in-one energy storage devices all-solid-state photothermal flexible low temperatures

linguistic landscape and its impacts on place-making in mountain destination:A case of Mogan Mountain Town of Huzhou City,China

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Journal of Mountain Science 2024年第5期21卷 1613-1629页

作者： li Chenyan lu Song LONG Cheng ZHU Jiaheng School of Tourism Shanghai Normal UniversityShanghai 200034China School of Environmental and Geographical Sciences Shanghai Normal UniversityShanghai 200034China

The place and placeness are believed to be a crucial perspective for comprehending the transformative dynamics of tourist destinations in the context of globalization and the rapid development of the tourism *** the material carrier of language,linguistic landscape is an intermediary for people to endow emotions and personalities into the place,becoming an effective path for exploring the place-making in a certain *** Mountain is a famous national tourist resort,which is located in Mogan Mountain Town,Deqing County,Huzhou City,*** is a good case area for studying the relationship between linguistic landscape and placemaking in tourist *** are two theories that form the theoretical foundation of the study,namely the place and the ***,the results showed the overall style of the linguistic *** labelling(52.7%),official signs(55.3%),and standardized Chinese characters predominantly shaped the linguistic landscape,with English and other languages being ***,from the perspective of three dimensions of the geosemiotics framework,such as inscription,language preference,and placement position,we conduct a comprehensive semiotic analysis of the linguistic landscape,which encompasses diverse facets such as fonts,materials,shifts in state,text vectors,and symmetrical ***,we explore the influence of linguistic landscapes on the place-making of Mogan Mountain through the dimensions of location,locale,and sense of *** information on linguistic landscapes indicates the geographical *** linguistic landscapes play an important role in constructing the language order,nostalgic atmosphere,exotic atmosphere,and elegant and tasteful lifestyle of the public space in Mogan *** of linguistic landscapes,including tourists and residents,generate and identify with the unique sense of place in Mogan *** linguistic landscapes construct the destinati

关键词： linguistic landscape Place-making Tourist destination Geosemiotics Place theory Place branding Mogan Mountain Town China

Geochronology and Geochemistry of the Xingxingxia Triassic A-type Granites in Central Tianshan,NW China:Petrogenesis and Tectonic Implications

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 337-351页

作者： HUANG Zengbao li Xiyao ZHAO Hao lu Qing Geological Survey of Gansu Province Lanzhou 735000China Key Laboratory of Submarine Geosciences and Prospecting Techniques MOE and College of Marine GeosciencesOcean University of ChinaQingdaoShandong 266100China Research Institute of Petroleum Exploration and Development Shengli OilfieldSINOPECDongyingShandong 257000China

The Triassic granitoids in Central Tianshan play a key role in determining the petrogenesis and tectonic evolution on the southern margin of the Central Asian orogenic *** this study,we present SHRIMP zircon U-Pb ages,Hf isotopic and geochemical data on the Xingxingxia biotite granite,amazonite granite and granitic pegmatite in Central Tianshan,NW *** U-Pb dating yielded formation ages of 242 Ma for the biotite granite and 240 Ma for the amazonite *** granitoid rocks have high K_(2)O with low MgO and CaO *** are enriched in Nb,Ta,Hf and Y,while being depleted in Ba and Sr,showing flat HREE patterns and negative Eu *** have typical A-type granite geochemical signatures with high Ga/A_(1)(8–13)and TFeO/(TFeO+MgO)ratios,showing an A_(2) affinity for biotite granite and an A_(1) affinity for amazonite granite and granitic *** ε_(Hf)(t)values of the granitoids are 0.45–2.66,with Hf model ages of 0.99–1.17 *** suggests that these A-type granites originated from partial melting of the lower *** propose that Xingxingxia Triassic A-type granites formed under lithospheric extension from post-orogenic to anorogenic intraplate settings and NE-trending regional strike-slip fault-controlled magma emplacement in the upper crust.

关键词： Triassic A-type granite Xingxingxia Central Tianshan Central Asian orogenic belt

Stochastic resonance of spinor condensates in optical cavity

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 80-87页

作者： Zheng-Chun li Bixuan Fan lu Zhou Weiping Zhang School of Physics and Astronomy and Tsung-Dao Lee InstituteShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Precision Spectroscopy School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China College of Physics and Communication Electronics Jiangxi Normal UniversityNanchang 330022China Shanghai Branch Hefei National LaboratoryShanghai 201315China Shanghai Research Center for Quantum Sciences Shanghai 201315China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Stochastic resonance is a phenomenon in which adding random noise to a system enhances the detection or transmission of a weak signal. It occurs when the noise interacts with the system's nonlinearity, thus improving signal-to-noise ratio and increasing sensitivity. Although parametric resonances in an atomic spinor Bose-Einstein condensate have been investigated, the question of whether one can observe stochastic resonance in such a system persists. In this study we propose a scheme for generating stochastic resonance in a cavity-spinor Bose-Einstein condensate coupling system. We demonstrate stochastic resonance through numerical calculations using the mean-field theory and truncated Wigner approximation methods. Furthermore, the characteristics of the system's response to noise and periodic signals are studied in detail. This study unravels a new scheme for observing stochastic resonance via linking atomic many-body physics with cavity quantum electrodynamics.

关键词： spinor condensate stochastic resonance optical cavity

Optimizing near-carbon-free nuclear energy systems:advances in reactor operation digital twin through hybrid machine learning algorithms for parameter identification and state estimation

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Nuclear Science and Techniques 2024年第8期35卷 177-203页

作者： li‑Zhan Hong He‑lin Gong Hong‑Jun Ji Jia‑liang lu Han li Qing li Paris Elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610041China

Accurate and efficient online parameter identification and state estimation are crucial for leveraging digital twin simulations to optimize the operation of near-carbon-free nuclear energy *** previous studies,we developed a reactor operation digital twin(RODT).However,non-differentiabilities and discontinuities arise when employing machine learning-based surrogate forward models,challenging traditional gradient-based inverse methods and their *** study investigated deterministic and metaheuristic algorithms and developed hybrid algorithms to address these *** efficient modular RODT software framework that incorporates these methods into its post-evaluation module is presented for comprehensive *** methods were rigorously assessed based on convergence profiles,stability with respect to noise,and computational *** numerical results show that the hybrid KNNLHS algorithm excels in real-time online applications,balancing accuracy and efficiency with a prediction error rate of only 1%and processing times of less than 0.1 ***,algorithms such as FSA,DE,and ADE,although slightly slower(approximately 1 s),demonstrated higher accuracy with a 0.3%relative L_2 error,which advances RODT methodologies to harness machine learning and system modeling for improved reactor monitoring,systematic diagnosis of off-normal events,and lifetime management *** developed modular software and novel optimization methods presented offer pathways to realize the full potential of RODT for transforming energy engineering practices.

关键词： Parameter identification State estimation Reactor operation digital twin Reduced order model Inverse problem

Review of Three-phase Soft Switching Inverters and Challenges for Motor Drives

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CES Transactions on Electrical Machines and Systems 2024年第2期8卷 177-190页

作者： Haifeng lu Qiao Wang Jianyun Chai Yongdong li IEEE the Department of Electrical Engineering Tsinghua UniversityBeijing 100084China the School of Electrical Engineering Xinjiang UniversityUrumqi 830047China

For electric vehicles (EVs),it is necessary to improve endurance mileage by improving the *** exists a trend towards increasing the system voltage and switching frequency,contributing to improve charging speed and power ***,this trend poses significant challenges for high-voltage and high-frequency motor controllers,which are plagued by increased switching losses and pronounced switching oscillations as consequences of hard *** deployment of soft switching technology presents a viable solution to mitigate these *** paper reviews the applications of soft switching technologies for three-phase inverters and classifies them based on distinct *** each type of inverter,the advantages and disadvantages are ***,the paper introduces the research progress and control methods of soft switching inverters (SSIs).Moreover,it presents a comparative analysis among the conventional hard switching inverters (HSIs),an active clamping resonant DC link inverter (ACRDCli) and an auxiliary resonant commuted pole inverter (ARCPI).Finally,the problems and prospects of soft switching technology applied to motor controllers for EVs are put forward.

关键词： Soft switching inverters Zero-voltage switching Electric vehicles Motor drives

Hexafluoropropylene oxide trimer acid,a perfluorooctanoic acid alternative,induces cardiovascular toxicity in zebrafish embryos

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Journal of Environmental Sciences 2024年第5期139卷 460-472页

作者： Sujie Sun li Zhang Xue li lu Zang ling Huang Junquan Zeng Zigang Cao Xinjun liao Zilin Zhong Huiqiang lu Jianjun Chen Jiangxi Engineering Laboratory of Zebrafish Modeling and Drug Screening for Human Diseases Jiangxi Key Laboratory of Developmental Biology of OrgansCenter for Clinical Research Center of the Affiliated Hospital of Jinggangshan UniversityJi’an 343009China Translational Research Institute of Brain and Brain-like Intelligence Shanghai Key Laboratory of Anesthesiology and Brain Functional ModulationDepartment of PediatricsShanghai Fourth People’s HospitalSchool of MedicineTongji UniversityShanghai 200434China State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants School of Environmental Sciences and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Interventional and Vascular Surgery Affiliated Hospital of Jinggangshan UniversityJi’an 343009China Department of Internal Medicine and Hematology Affiliated Hospital of Jinggangshan UniversityJi’an 343009China

As an increasingly used alternative to perfluorooctanoic acid(PFOA),hexafluoropropylene oxide trimer acid(HFPO-TA)has been widely detected in global water ***,little is known regarding its toxic effects on cardiovascular ***,zebrafish embryos were treated with egg water containing 0,60,120,or 240 mg/L *** showed that HFPO-TA treatment led to a significant reduction in both larval survival percentage and heart ***,HFPO-TA exposure caused severe pericardial edema and elongation of the sinus venous to bulbus arteriosus distance(SV-BA)in Tg(myl7:GFP)transgenic larvae,disrupting the expression of genes involved in heart development and thus causing abnormal heart *** sprouting angiogenesis was observed in the 120 and 240 mg/L exposed Tg(fli:GFP)transgenic ***-TA treatment also impacted the mRNA levels of genes involved in the vascular endothelial growth factor(VEGF)pathway and embryonic vascular ***-TA exposure significantly decreased erythrocyte number in Tg(gata1:DsRed)transgenic embryos and influenced gene expression associated with the heme metabolism ***-TA also induced oxidative stress and altered the transcriptional levels of genes related to cell cycle and apoptosis,inhibiting cell proliferation while promoting ***,HFPO-TA exposure may induce abnormal development of the cardiovascular and hematopoietic systems in zebrafish embryos,suggesting it may not be a suitable or safe alternative for PFOA.

关键词： Hexafluoropropylene oxide trimer acid Heart development Vascular development Hemopoiesis Zebrafish embryos

Update on evidence-based clinical application of sodium-glucose cotransporter inhibitors:Insight to uncommon cardiovascular disease scenarios in diabetes

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World Journal of Diabetes 2024年第7期15卷 1461-1476页

作者： Shi-bing Tao Xi lu Zi-Wei Ye Nan-Wei Tong Department of Endocrinology and Metabolism West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina Research Centre for Diabetes and Metabolism West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Endocrinology and Metabolism Ziyang Central HospitalZiyang 641300Sichuan ProvinceChina

In this paper,we concentrate on updating the clinical research on sodium-glucose cotransporter inhibitors(SGLTis)for patients with type 2 diabetes who have heart failure with a preserved injection fraction,acute heart failure,atrial fibrillation,primary prevention of atherosclerotic cardiovascular disease/cardiovascular disease,and acute myocardial *** searched the data of randomized controlled trials and meta-analyses of SGLTis in patients with diabetes from PubMed between January 1,2020 and April 6,2024 for our *** to our review,certain SGLTis(empagliflozin,dapagliflozin,canagliflozin,and tofogliflozin),but not sodium-glucose cotransporter 1 inhibitor(SGLT1i),exhibit relatively superior clinical safety and effectiveness for treating the abovementioned *** utilization of SGLTis in these patients can foster clinical improvement and offer an alternative medication ***,clinical trials involving SGLTis for certain diseases have relatively small sample sizes,brief intervention durations,and conclusions based on weak evidence,necessitating additional *** findings are significant and valuable for providing a more comprehensive reference and new possibilities for the clinical utilization and scientific exploration of SGLTis.

关键词： Sodium-glucose cotransporter inhibitors Diabetes Heart failure Atrial fibrillation Atherosclerosis Cardiovascular disease Acute myocardial infarction