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Dual-assisted high-precision tracking technique for wideband multiplexed signals in new generation gNSS

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Satellite Navigation 2024年第1期5卷 52-73页

作者： Yunhan Qi Zheng Yao Mingquan lu Department of Electronic Engineering Tsinghua UniversityBeijing100084China Beijing National Research Center for Information Science and Technology Beijing100084China

With the evolution of global Navigation Satellite System(gNSS),new generation gNSS signals have adopted the dual-frequency multiplexing modulation techniques,which jointly modulate multiple signals located on multiple sub-frequencies into a Wideband Multiplexed Signal(WMS).Although WMSs were proposed initially to reduce the complexity of satellite transmitters and improve the transmission efficiency of signals,their multi-component structures and wide root mean square bandwidths introduced by high-frequency subcarriers also provide the possibility to improve the gNSS ranging ***,this paper proposes a Dual-assisted Multi-component Tracking(DMT)technique,which can not only fully use high-frequency subcarriers in WMSs,but also effectively track carrier,subcarrier,and code by jointly utilizing all components in *** this paper,the tracking and ranging performances of DMT are comprehensively analyzed theoretically and by simulation and real *** results show that compared with existing WMS tracking methods,DMT can achieve tracking results with lower tracking jitters and ranging results with higher precision,providing a highly advantageous solution for new generation gNSS signal processing.

关键词： Wideband multiplexed signal Dual-assisted Multi-component High precision tracking

Determination of the critical rainfall of runoff-initiated debris flows by the perspective of physical mechanics and Shields stress

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Journal of Mountain Science 2024年第4期21卷 1160-1173页

作者： MA Chao ZHU Yongtai lu lu DU Cui LYU Liqun DONg Jie School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China Beijing Institute of geological Hazard Prevention Beijing 100120China School of Software Engineering Chengdu University of Information TechnologyChengdu610225China Civil and Environmental Engineering Department Clarkson UniversityNY 13699USA

The critical rainfall of runoff-initiated debris flows is utmost importance for local early hazard *** paper presents research on the critical rainfall of runoff-initiated debris flows through comparisons between slope gradients and three key factors,including topographic contributing area,dimensionless discharge,and Shields *** rainfall amount was estimated by utilizing in-situ rainfall records and a slope-dependent Shields stress model was *** created model can predict critical Shields stress more accurately than the other two ***,a new dimensionless discharge equation was proposed based on the corresponding discharge-gradient *** new equation,along with factors such as contributing area above bed failure sites,channel width,and mean diameter of debris flow deposits,predicts a smaller rainfall amount than the in-situ measured *** the slope-dependent Shields stress model performs well and the estimated rainfall amount is lower than the in-situ records,the sediment initiation in the experiments falls within sheet flow regime due to a large Shields ***,further sediment initiation experiments at a steeper slope range are expected in the future to ensure that the sediment transport belongs to mass failure regime characterized by a low level of Shields ***,a more accurate hazard forecast on the runoff-initiated debris flow holds promise when the corresponding critical slope-dependent dimensionless discharge of no motion,fluvial sediment transport,mass flow regime,and sheet flow regime are considered.

关键词： Infinite slope stability Shields stress Contributing area-slope gradient Rainfall back estimation

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Divalent anion intercalation and etching-hydrolysis strategies to construct ultra-stable electrodes for seawater splitting

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Science China Chemistry 2024年第2期67卷 687-695页

作者： Jiajia lu Yang Liu Han-Pu Liang Key Laboratory of Biofuels Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao266101China Henan Provincial Key Laboratory of Nanocomposites and Applications Institute of Nano-Structured Functional MaterialsHuanghe Science and Technology CollegeZhengzhou450006China School of Materials Science and Engineering Henan Normal UniversityXinxiang453007China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China Shandong Energy Institute Qingdao266101China

Developing stable electrodes for seawater splitting remains a great challenge due to the detachment of catalysts at a large operating current and severe anode corrosion caused by ***,divalent anion intercalation and etching-hydrolysis strategies are deployed to synthesize the ultra-stable anode,dendritic Fe(OH)_(3) grown on Ni(SO_4)_(0.3)(OH)_(1.4)–Ni(OH)_(2).Experimental results reveal that the anode exhibits good activity and excellent stability in alkaline simulated *** 500 h,the current density operated at 1.72 V remains 99.5%,about 210 m A cm^(-2).The outstanding stability originates from the etchinghydrolysis strategy,which strengthens the interaction between the catalyst and the carrier and retards thus the detachment of catalysts at a large current ***,theoretical simulations confirm that the intercalated divalent anions,such as SO_4^(2-) and CO_(3)^(2-),can weaken the adsorption strength of chlorine on the surface of catalysts and hinder the coupling and hybridization between chlorine and nickel,which slows down the anode corrosion and improves catalytic ***,the twoelectrode system shows the remarkable 95.1% energy efficiency at 2,000 A m-2and outstanding stability in 6 mol L^(-1) KOH +seawater at 80 ℃.

关键词： seawater splitting stability divalent anion intercalation etching-hydrolysis

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时间旅行的量子门

物理学报 2024年第2期73卷 89-92页

作者：王粲陆朝阳陈明城中国科学技术大学近代物理系合肥微尺度物质科学国家研究中心合肥230026 中国科学技术大学中国科学院量子信息与量子科技前沿卓越创新中心上海201315

量子计算可以解决经典计算难于求解的问题,在物理原理允许范围内扩大了可有效计算的问题范围,对经典计算的扩展丘奇图灵论题提出了挑战.这里我们讨论一个有趣的问题:通过突破物理原理限制来实现更强大的计算机,进一步扩展量子计算机的能... 详细信息

量子计算可以解决经典计算难于求解的问题,在物理原理允许范围内扩大了可有效计算的问题范围,对经典计算的扩展丘奇图灵论题提出了挑战.这里我们讨论一个有趣的问题:通过突破物理原理限制来实现更强大的计算机,进一步扩展量子计算机的能力.我们考虑一种全新的操纵能力,让量子计算可以实现时间穿梭旅行的量子控制门.这是量子门线路图形语言的一个符合直觉的扩展,作为例子,我们展示了一个可以有效求解SAT难题的扩展量子算法.我们的结果有助于更深刻地理解计算和物理原理之间的关系.

关键词：扩展丘奇图灵论题时间旅行闭合类时曲线量子计算机 P与NP问题

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Seizure as the main presenting manifestation of three patients with acute glufosinate-ammonium poisoning

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 354-358页

作者： Ping WANg Congying SONg Xuan lu Yuanqiang lu Department of Emergency Medicine the First Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 3100030 China Zhejiang Key Laboratory for Diagnosis and Treatment of Physic chemical and Aging related Injuries Hangzhou 310003China Department of geriatric Medicine the First Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310003China

glufosinate-ammonium herbicides are the most widely used broad-spectrum,non-selective herbicides in the ***-ammonium is a structural analogue of glutamate(glu)which can irreversibly inhibit the activity of glutamine synthetase(gS)and glu decarboxylase in plants,thereby blocking the synthesis of glutamine(gln)from glu and ammonia(Hoerlein,1994).This causes the plants to die because of the nitrogen metabolism disorder and subsequent intracellular accumulation of *** humans,the characteristic features of glufosinate-ammonium herbicide poisoning include gastrointestinal symptoms and neurotoxicity(Watanabe and Sano,1998).

关键词： ammonium ammonia thereby

g protein-coupled receptors(gPCRs):advances in structures,mechanisms,and drug discovery

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1938-1980页

作者： Mingyang Zhang Ting Chen Xun lu Xiaobing Lan Ziqiang Chen Shaoyong lu Key Laboratory of Protection Development and Utilization of Medicinal Resources in Liupanshan AreaMinistry of EducationPeptide&Protein Drug Research CenterSchool of PharmacyNingxia Medical UniversityYinchuan 750004China Medicinal Chemistry and Bioinformatics Center Shanghai Jiao Tong University School of MedicineShanghai 200025China Department of Cardiology Changzheng HospitalAffiliated to Naval Medical UniversityShanghai 200003China Department of Orthopedics Changhai HospitalAffiliated to Naval Medical UniversityShanghai 200433China

g protein-coupled receptors(gPCRs),the largest family of human membrane proteins and an important class of drug targets,play a role in maintaining numerous physiological *** or antagonist,orthosteric effects or allosteric effects,and biased signaling or balanced signaling,characterize the complexity of gPCR dynamic *** this study,we first review the structural advancements,activation mechanisms,and functional diversity of *** then focus on gPCR drug discovery by revealing the detailed drug-target interactions and the underlying mechanisms of orthosteric drugs approved by the US Food and Drug Administration in the past five ***,an up-to-date analysis is performed on available gPCR structures complexed with synthetic small-molecule allosteric modulators to elucidate key receptor-ligand interactions and allosteric ***,we highlight how the widespread gPCR-druggable allosteric sites can guide structure-or mechanism-based drug design and propose prospects of designing bitopic ligands for the future therapeutic potential of targeting this receptor family.

关键词： steric designing mechanisms

Effectiveness of magnetic resonance imaging and spiral computed tomography in the staging and treatment prognosis of colorectal cancer

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World Journal of gastrointestinal Surgery 2024年第7期16卷 2135-2144页

作者： lu-Na Bai lu-Xian Zhang Department of Radiology Zhongshan Hospital Xiamen UniversityXiamen 361004Fujian ProvinceChina

BACKgROUND Colorectal cancer(CRC)is a prevalent cancer type in clinical settings;its early signs can be difficult to detect,which often results in late-stage diagnoses in many *** early detection and diagnosis of CRC are crucial for improving treatment success and patient survival ***,imaging techniques have been hypothesized to be essential in managing CRC,with magnetic resonance imaging(MRI)and spiral computed tomography(SCT)playing a significant role in enhancing diagnostic and treatment *** To explore the effectiveness of MRI and SCT in the preoperative staging of CRC and the prognosis of laparoscopic *** Ninety-five individuals admitted to zho.gshan Hospital Xiamen University underwent MRI and SCT and were diagnosed with *** precision of MRI and SCT for the presurgical classification of CRC was assessed,and pathological staging was used as a *** operating characteristic curves were used to evaluate the diagnostic efficacy of blood volume,blood flow,time to peak,permeability surface,blood reflux constant,volume transfer constant,and extracellular extravascular space volume fraction on the prognosis of patients with *** Pathological biopsies confirmed the following CRC stages:23,23,32,and 17 at T1,T2,T3,and T4,*** were 39 cases at the N0 stage,22 at N1,34 at N2,44 at M0 stage,and 51 at *** pathological findings as the benchmark,the combined use of MRI and SCT for preoperative TNM staging in patients with CRC demonstrated superior sensitivity,specificity,and accuracy compared with either modality alone,with a statistically significant difference in accuracy(Pg characteristic curve analysis revealed the predictive values for laparoscopic treatment prognosis,as indicated by the areas under the curve for blood volume,blood flow,time to peak,and permeability surface,blood reflux constant,volume transfer constant,and extracellular extravascular space volu

关键词： Magnetic resonance imaging Spiral computed tomography Colorectal cancer Prognosis Receiver operating characteristic curve Retrospective study

Semiotics and political discourse in the post-truth era

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Language and Semiotic Studies 2024年第1期10卷 65-82页

作者： BetülÇanakpınar Murat Kalelioğlu V.Doğan günay Istinye University IstanbulTürkiye School of Foreign Languages T C Mardin Artuklu UniversityMardinTürkiye Faculty of Literature Department of LinguisticsDokuz Eylül UniversityIzmirTürkiye

The concept of post-truth has been on the world’s agenda since *** this concept,which is frequently encountered in political life,provides the speaker with a freer speaking ***,instead of presenting the reality to their constituents as it is,want to reshape this reality according to their own ideology and present it to the *** have certain objectives in creating such a virtual *** aims can be listed as keeping the voters,increasing the voting potential,and attracting undecided voters to their *** common result of all these aims is to gain political power or to remain in the existing ***-truth reality is constructed relatively more easily in social media *** construction of reality can be through beliefs or *** such ways,the recipient is tried to be persuaded,and thus behavioral change is *** of the most necessary subjects for this artificial reality atmosphere is the *** idea that the anti-subject does not know the truth that we(you and I)know and believe and is trying to destroy it is the main theme of post-truth *** try to persuade the voters to believe in their own truth by expressing this idea to *** are many examples of this around the *** this study,firstly,the concept of post-truth is examined and its various definitions are *** distinctions between the concepts of real and truth are analyzed and then it is explained how and for what purposes the concept of post-truth is used in *** the comparison of post-truth and fake news,the concept is discussed within the framework of sender-receiver interaction in terms of *** concept is tried to be elucidated with the modalities such as/convincing/,/believing/,/being/,/appearing/.Besides,using the semiotic square,the study also tries to reveal the different purposes and forms of use of the concept of *** a result,it has been observed

关键词： semiotics discourse politics post-truth fake news

Online distributed optimization with stochastic gradients:high probability bound of regrets

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Control Theory and Technology 2024年第3期22卷 419-430页

作者： Yuchen Yang Kaihong lu Long Wang Center for Systems and Control College of EngineeringPeking UniversityBeijing 100871China College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590ShandongChina

In this paper,the problem of online distributed optimization subject to a convex set is studied via a network of *** agent only has access to a noisy gradient of its own objective function,and can communicate with its neighbors via a *** handle this problem,an online distributed stochastic mirror descent algorithm is *** works on online distributed algorithms involving stochastic gradients only provide the expectation bounds of the *** from them,we study the high probability bound of the regrets,i.e.,the sublinear bound of the regret is characterized by the natural logarithm of the failure probability's *** mild assumptions on the graph connectivity,we prove that the dynamic regret grows sublinearly with a high probability if the deviation in the minimizer sequence is sublinear with the square root of the time ***,a simulation is provided to demonstrate the effectiveness of our theoretical results.

关键词： Distributed optimization Online optimization Stochastic gradient High probability