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Dynamical localization in a non-Hermitian Floquet synthetic system
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作者 可汗 张嘉明 +1 位作者 霍良 赵文垒 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期147-151,共5页
We investigate the non-Hermitian effects on quantum diffusion in a kicked rotor model where the complex kicking potential is quasi-periodically modulated in the time domain.The synthetic space with arbitrary dimension... We investigate the non-Hermitian effects on quantum diffusion in a kicked rotor model where the complex kicking potential is quasi-periodically modulated in the time domain.The synthetic space with arbitrary dimension can be created by incorporating incommensurate frequencies in the quasi-periodical modulation.In the Hermitian case,strong kicking induces the chaotic diffusion in the four-dimension momentum space characterized by linear growth of mean energy.We find that the quantum coherence in deep non-Hermitian regime can effectively suppress the chaotic diffusion and hence result in the emergence of dynamical localization.Moreover,the extent of dynamical localization is dramatically enhanced by increasing the non-Hermitian parameter.Interestingly,the quasi-energies become complex when the non-Hermitian parameter exceeds a certain threshold value.The quantum state will finally evolve to a quasi-eigenstate for which the imaginary part of its quasi-energy is large most.The exponential localization length decreases with the increase of the non-Hermitian parameter,unveiling the underlying mechanism of the enhancement of the dynamical localization by nonHermiticity. 展开更多
关键词 Floquet system non-Hermitian physics dynamical localization
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Two-person device-free localization system based on ZigBee and transformer
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作者 刘天蒙 YANG Hai xiao WU Hong 《High Technology Letters》 EI CAS 2024年第1期61-67,共7页
Most studies on device-free localization currently focus on single-person scenarios.This paper proposes a novel method for device-free localization that utilizes ZigBee received signal strength indication(RSSI)and a T... Most studies on device-free localization currently focus on single-person scenarios.This paper proposes a novel method for device-free localization that utilizes ZigBee received signal strength indication(RSSI)and a Transformer network structure.The method aims to address the limited research and low accuracy of two-person device-free localization.This paper first describes the construction of the sensor network used for collecting ZigBee RSSI.It then examines the format and features of ZigBee data packages.The algorithm design of this paper is then introduced.The box plot method is used to identify abnormal data points,and a neural network is used to establish the mapping model between ZigBee RSSI matrix and localization coordinates.This neural network includes a Transformer encoder layer as the encoder and a fully connected network as the decoder.The proposed method's classification accuracy was experimentally tested in an online test stage,resulting in an accuracy rate of 98.79%.In conclusion,the proposed two-person localization system is novel and has demonstrated high accuracy. 展开更多
关键词 device-free localization deep learning ZIGBEE
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Navigating the pathways:TAR-DNA-binding-protein-43 aggregation,axonal transport,and local synthesis in amyotrophic lateral sclerosis pathology
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作者 Ori Bar Avi Eran Perlson 《Neural Regeneration Research》 SCIE CAS 2025年第10期2921-2922,共2页
Neurons are highly polarized cells with axons reaching over a meter long in adult humans.To survive and maintain their proper function,neurons depend on specific mechanisms that regulate spatiotemporal signaling and m... Neurons are highly polarized cells with axons reaching over a meter long in adult humans.To survive and maintain their proper function,neurons depend on specific mechanisms that regulate spatiotemporal signaling and metabolic events,which need to be carried out at the right place,time,and intensity.Such mechanisms include axonal transport,local synthesis,and liquid-liquid phase separations.Alterations and malfunctions in these processes are correlated to neurodegenerative diseases such as amyotrophic lateral sclerosis(ALS). 展开更多
关键词 SYNTHESIS local AGGREGATION
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Abnormal Secondary Growth and Histochemical Localization of Alkaloids in Root System of Aconitum flavum Hand.-Mazz.
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作者 祁建钊 郭继元 徐青 《Agricultural Science & Technology》 CAS 2011年第9期1313-1317,共5页
[Objective] The purpose of this study was to clarify the structure,growth pattern and histochemical localization of alkaloids in root system of Aconitum flavum Hand.-Mazz.[Method] Paraffin sectioning and histochemistr... [Objective] The purpose of this study was to clarify the structure,growth pattern and histochemical localization of alkaloids in root system of Aconitum flavum Hand.-Mazz.[Method] Paraffin sectioning and histochemistry were employed for performing the analysis in this study.[Result] The root system of Aconitum flavum Hand.-Mazz.consists of taproot,lateral root and adventitious root.The primary structure of root system is normal,but secondary structure shows abnormal.The cambium and the extra cambium of taproot form a "U"-shaped secondary vascular bundle and tertiary bundle in abnormal secondary structure.The sieve tube group is made of little sieve tube group which is differentiated from primary phloem and cambium.Meanwhile,the secondary xylem in tuberous root also appears to be a "U" shape.Parenchyma cells of secondary phloem occupy most of the tuberous root.The sieve tube group of tuberous root is mainly differentiated from parenchyma cell of secondary phloem.[Conclusion] The difference in abnormal secondary structure of taproot and tuberous root are attributed to their varied cambium compose and activity pattern.Alkaloids are mainly accumulated in parenchyma cell of the inside cortex and between bundle in taproot,while parenchyma of secondary phloem and pith in tuberous root. 展开更多
关键词 Aconitum flavum Hand. - Mazz. Root system Abnormal secondary growth ALKALOIDS Histochemical localization
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Efficacy and safety of local anaesthetics for prematurejaculation: a systematic review and meta-analysis 被引量:11
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作者 Jia-Dong Xia You-Feng Hart +2 位作者 Liu-Hua Zhou Yun Chen Yu-Tian Dai 《Asian Journal of Andrology》 SCIE CAS CSCD 2013年第4期497-502,I0008,共7页
To assess the efficacy and safety of local anaesthetics for premature ejaculation (PE), a systematic review of the literature was performed using the Cochrane Library, PUBMED and EMBASE. We screened and retrieved th... To assess the efficacy and safety of local anaesthetics for premature ejaculation (PE), a systematic review of the literature was performed using the Cochrane Library, PUBMED and EMBASE. We screened and retrieved the randomized controlled trials on the treatment of PE with local anaesthetics. End points included intravaginal ejaculation latency time (IELT), patient-reported outcome assessments and adverse events. Meta-analyses were conducted with Stata 11.0. In total, seven publications involving 566 patients with local anaesthetics and 388 with placebos strictly met our eligibility criteria. Meta-analyses showed that after the patients were treated with the local anaesthetics, the value of the standardized mean difference of the changes in IELT was 5.02 (95% Ch 3.03- 7.00). A higher rate of adverse events occurred compared with placebos (odds ratio: 3.30, 95% Ch 1.71-6.36), but these events were restricted to local side effects. In addition, significantly greater improvement was observed in patient-reported outcomes. In summary, local anaesthetics can prolong IELT and improve ejaculatory control and sexual satisfaction. 展开更多
关键词 local anaesthetics premature ejaculation (PE) randomized controlled trial systematic review
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Folded localized excitations in the (2+1)-dimensional modified dispersive water-wave system 被引量:7
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作者 雷燕 马松华 方建平 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第1期138-142,共5页
By using a mapping approach and a linear variable separation approach, a new family of solitary wave solutions with arbitrary functions for the (2+1)-dimensional modified dispersive water-wave system (MDWW) is de... By using a mapping approach and a linear variable separation approach, a new family of solitary wave solutions with arbitrary functions for the (2+1)-dimensional modified dispersive water-wave system (MDWW) is derived. Based on the derived solutions and using some multi-valued functions, we obtain some novel folded localized excitations of the system. 展开更多
关键词 mapping approach modified dispersive water-wave system solitary wave solution folded localized excitation
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Fault Diagnosis Approach of Local Ventilation System in Coal Mines Based on Multidisciplinary Technology 被引量:18
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作者 GONG Xiao-yan XUE He +1 位作者 TAO Xin-li HU Ning 《Journal of China University of Mining and Technology》 EI 2006年第3期317-320,共4页
In order to reduce the probability of fault occurrence of local ventilation system in coal mine and prevent gas from exceeding the standard limit, an approach incorporating the reliability analysis, rough set theory, ... In order to reduce the probability of fault occurrence of local ventilation system in coal mine and prevent gas from exceeding the standard limit, an approach incorporating the reliability analysis, rough set theory, genetic algorithm (GA), and intelligent decision support system (IDSS) was used to establish and develop a fault diagnosis system of local ventilation in coal mine. Fault tree model was established and its reliability analysis was performed. The algorithms and software of key fault symptom and fault diagnosis rule acquiring were also analyzed and developed. Finally, a prototype system was developed and demonstrated by a mine instance. The research results indicate that the proposed approach in this paper can accurately and quickly find the fault reason in a local ventilation system of coal mines and can reduce difficulty of the fault diagnosis of the local ventilation system, which is significant to decrease gas exploding accidents in coal mines. 展开更多
关键词 fault diagnosis local ventilation rough set theory genetic algorithm IDSS
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Waveform diversity based sonar system for target localization 被引量:6
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作者 Lijie Zhang dianguo Huang +3 位作者 Yong Jin Yunshan Hou Min Jiang Qunfei Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第2期186-190,共5页
A new monostatic array system taking advantage of diverse waveforms to improve the performance of underwater tar- get localization is proposed. Unlike the coherent signals between different elements in common active a... A new monostatic array system taking advantage of diverse waveforms to improve the performance of underwater tar- get localization is proposed. Unlike the coherent signals between different elements in common active array, the transmitted signals from different elements here are spatially orthogonal waveforms which allow for array processing in the transit mode and result in an extension of array aperture. The mathematical derivation of Capon estimator for this sonar system is described in detail. And the performance of this orthogonal-waveform based sonar is an- alyzed and compared with that of its phased-array counterpart by water tank experiments. Experimental results show that this sonar system could achieve 12 dB-15 dB additional array gain over its phased-array counterpart, which means a doubling of maximum detection range. Moreover, the angular resolution is significantly improved at lower SNR. 展开更多
关键词 SONAR orthogonal signal transmission CAPON target localization.
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Implementation and Evaluation of Local Dynamic Map in Safety Driving Systems 被引量:13
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作者 Hideki Shimada Akihiro Yamaguchi +1 位作者 Hiroaki Takada Kenya Sato 《Journal of Transportation Technologies》 2015年第2期102-112,共11页
Cooperative safety driving systems using vehicle-to-vehicle and vehicle-to infrastructure communication are developed. Sensor data of vehicles and infrastructures are communicated in the cooperative safety driving sys... Cooperative safety driving systems using vehicle-to-vehicle and vehicle-to infrastructure communication are developed. Sensor data of vehicles and infrastructures are communicated in the cooperative safety driving system. LDM (Local Dynamic Map) is standardized by ETSI (European Telecommunications Standards Institute) to manage the vehicle sensor data and the map data. Implementations of LDM are reported on documents of ETSI, but there are no numerical results. The implementations of LDM are deployed the database management system. We think that the response time of the database becomes higher as the number of vehicles grows. In this paper, we have implemented and evaluated the LDM with the collision detection application. 展开更多
关键词 local DYNAMIC MAP ITS COOPERATIVE Safety Driving systemS
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Determining the Spectrum of the Nonlinear Local Lyapunov Exponents in a Multidimensional Chaotic System 被引量:6
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作者 Ruiqiang DING Jianping LI Baosheng LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第9期1027-1034,共8页
For an n-dimensional chaotic system, we extend the definition of the nonlinear local Lyapunov exponent (NLLE) from one- to n-dimensional spectra, and present a method for computing the NLLE spectrum. The method is t... For an n-dimensional chaotic system, we extend the definition of the nonlinear local Lyapunov exponent (NLLE) from one- to n-dimensional spectra, and present a method for computing the NLLE spectrum. The method is tested on three chaotic systems with different complexity. The results indicate that the NLLE spectrum realistically characterizes the growth rates of initial error vectors along different directions from the linear to nonlinear phases of error growth. This represents an improvement over the traditional Lyapunov exponent spectrum, which only characterizes the error growth rates during the linear phase of error growth. In addition, because the NLLE spectrum can effectively separate the slowly and rapidly growing perturbations, it is shown to be more suitable for estimating the predictability of chaotic systems, as compared to the traditional Lyapunov exponent spectrum. 展开更多
关键词 Lyapunov exponent nonlinear local Lyapunov exponent PREDICTABILITY
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Bevacizumab in the pre-operative treatment of locally advanced rectal cancer: A systematic review 被引量:5
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作者 Lorenzo Fornaro Chiara Caparello +5 位作者 Caterina Vivaldi Virginia Rotella Gianna Musettini Alfredo Falcone Editta Baldini Gianluca Masi 《World Journal of Gastroenterology》 SCIE CAS 2014年第20期6081-6091,共11页
Despite advances in the management of patients with locally advanced, non-metastatic rectal adenocarcinoma (LARC), prognosis remains largely unsatisfactory due to a high rate of distant relapse. In fact, currently ava... Despite advances in the management of patients with locally advanced, non-metastatic rectal adenocarcinoma (LARC), prognosis remains largely unsatisfactory due to a high rate of distant relapse. In fact, currently available neoadjuvant protocols, represented by fluoropyrimidine-based chemo-radiotherapy (CT-RT) or short-course RT, together with improved surgical techniques, have largely reduced the risk of local relapse, with limited impact on distant recurrence. Available results of phase III trials with additional cytotoxic agents combined with standard CT-RT are disappointing, as no significant reduction in the risk of recurrence has been demonstrated. In order to improve the control of micrometastatic disease, integrating targeted agents into neoadjuvant treatment protocols thus offers a rational approach. In particular, the antiangiogenic agent bevacizumab has demonstrated synergistic activity with both CT and RT in pre-clinical and clinical models, and thus may represent a suitable companion in the neoadjuvant treatment of LARC. Preliminary results of phase&#x02005;I-II clinical studies are promising and suggest potential clinical parameters and molecular predictive biomarkers useful for patient selection: treatment personalization is indeed the key in order to maximize the benefit while reducing the risk of more complex neoadjuvant treatment schedules. 展开更多
关键词 BEVACIZUMAB CHEMOTHERAPY locally advanced rectal cancer Neoadjuvant treatment RADIOTHERAPY
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Local Responses to Macro Development Policies and Their Effects on Rural System in China's Mountainous Regions:The Case of Shuanghe Village in Sichuan Province 被引量:7
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作者 LI Yu-rui LIU Yan-sui +1 位作者 LONG Hua-lou WANG Jie-yong 《Journal of Mountain Science》 SCIE CSCD 2013年第4期588-608,共21页
China has promulgated a series of policies including the Western Development Program, the Grain for Green Project, agricultural support policies and building a new countryside strategy to eliminate east-west differenc... China has promulgated a series of policies including the Western Development Program, the Grain for Green Project, agricultural support policies and building a new countryside strategy to eliminate east-west differences and urban-rural disparities since the late 1990s. This paper gives a holistic examination on local responses to the four typical macro socio-economic development policies and their effects on rural system based on a case study of a mountainous village in southern Sichuan Province. The results showed that the policies have not moved the case study village from its historically marginal status. To some extent, its socio-economic situation might have been worsened by accelerated out- migration of the youth, loss of agricultural land due to afforestation and industrial plants, increased fire hazard due to afforestation and reforestation, increased environmental pollution due to industrial enterprises attracted to the village and a steep decline in agricultural production due to loss of and inefficient use of cultivated land. Factors causing local villages' dilemmas include the nonuniformity of actors' objectives, finiteness of villagers' abilities, and the imperfect incentive and restraint mechanism for local government's activities under existing policy framework composed of uncoordinated one-size-fits- all policies. We suggest that China's rural policy in the new period should gradually shift from a sectoral to a place-based one, from top-down incentives to the development of bottom-up projects, and fully recognize the diversity of rural space, so as to lift localcapacities and make good use of the knowledge shared by different actors. Moreover, it is also necessary to integrate the various sectoral policies, and improve the interministerial and interdepartmental coordination of rural policies at regional and local levels. 展开更多
关键词 local responses Western DevelopmentProgram Grain for Green Project Agriculturalsupport policies Building new countryside Ruralpolicy evaluation
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Continuous wound infusion of local anaesthetic agents following colorectal surgery:Systematic review and meta-analysis 被引量:4
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作者 Alan Karthikesalingam Stewart R Walsh +3 位作者 Sheraz R Markar Umar Sadat Tjun Y Tang Charles M Malata 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第34期5301-5305,共5页
AIM:To provide a specifi c review and meta-analysis of the available evidence for continuous wound infusion of local anaesthetic agents following midline laparoto-my for major colorectal surgery. METHODS: Medline, Emb... AIM:To provide a specifi c review and meta-analysis of the available evidence for continuous wound infusion of local anaesthetic agents following midline laparoto-my for major colorectal surgery. METHODS: Medline, Embase, trial registries, conference proceedings and article reference lists were searched to identify randomised, controlled trials of continuous wound infusion of local anaesthetic agents following colorectal surgery. The primary outcomes were opioid consumption, pain visual analogue scores (VASs), return to bowel function and length of hospital stay. Weighted mean difference were calculated for continuous outcomes. RESULTS: Five trials containing 542 laparotomy wounds were eligible for inclusion. There was a sig- nificant decrease in post-operative pain VAS at rest on day 3 (weighted mean difference: -0.43; 95% CI: -0.81 to -0.04; P = 0.03) but not on post-operative day 1 and 2. Local anaesthetic infusion was associated with a signifi cant reduction in pain VAS on movement on all three post-operative days (day 1 weighted mean difference: -1.14; 95% CI: -2.24 to -0.041; P = 0.04, day 2 weighted mean difference: -0.97, 95% CI: -1.91to -0.029; P = 0.04, day 3 weighted mean difference: -0.61; 95% CI: 1.01 to -0.20; P = 0.0038). Local an- aesthetic wound infusion was associated with a signifi - cant decrease in total opioid consumption (weighted mean difference: -40.13; 95% CI: -76.74 to -3.53; P = 0.03). There was no signifi cant decrease in length of stay (weighted mean difference: -20.87; 95% CI: -46.96 to 5.21; P = 0.12) or return of bowel function (weighted mean difference: -9.40; 95% CI: -33.98 to 15.17; P = 0.45). CONCLUSION: The results of this systematic re- view and meta-analysis suggest that local anaesthetic wound infusion following laparotomy for major color- ectal surgery is a promising technique but do not pro- vide conclusive evidence of benefi t. Further research is required including cost-effectiveness analysis. 展开更多
关键词 Colorectal surgery LAPAROTOMY local anaesthesia INFUSION Wound healing
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Research on Signal of Field Monitor of 7220A Localizer Beacon Subsystem of ILS 被引量:7
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作者 C. Q. Qu 《Open Journal of Antennas and Propagation》 2015年第4期37-50,共14页
From the actual perspective of working principle of localizer beacon subsystem of Instrument Landing System (ILS), consideration of the distance information from localizer antenna to field monitor antenna and wide ape... From the actual perspective of working principle of localizer beacon subsystem of Instrument Landing System (ILS), consideration of the distance information from localizer antenna to field monitor antenna and wide aperture effect of localizer antenna, broke through the limitation of signals synthesized only far-field (FF), established the near-field (NF) model. The three-dimensional mathematical model of localizer beacon was designed, and the signals at both near-field and far-field were analyzed qualitatively. At the environment of Antenna Fault as well as Antenna Distribution Unit (ADU) phase shifter simulation, the characteristics of near-field and far-field were also compared. The simulation results showed that the model met the requirement of theory of localizer beacon, and the gap between two models was so evident, which resulted from the broken geometric symmetry in NF area. The model could provide valuable theoretical basis for performance evaluation and maintenance of the ILS, and meanwhile, provide reference for the further analysis of localizer beacon. 展开更多
关键词 Instrument Landing system (ILS) localIZER BEACON Near FIELD SIGNAL Syntheses
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Hybrid ToA and IMU indoor localization system by various algorithms 被引量:4
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作者 CHEN Xue-chen CHU Sheng +1 位作者 LI Fan CHU Guang 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第8期2281-2294,共14页
In this paper, we integrate inertial navigation system (INS) with wireless sensor network (WSN) to enhance the accuracy of indoor localization. Inertial measurement unit (IMU), the core of the INS, measures the accele... In this paper, we integrate inertial navigation system (INS) with wireless sensor network (WSN) to enhance the accuracy of indoor localization. Inertial measurement unit (IMU), the core of the INS, measures the accelerated and angular rotated speed of moving objects. Meanwhile, the ranges from the object to beacons, which are sensor nodes with known coordinates, are collected by time of arrival (ToA) approach. These messages are simultaneously collected and transmitted to the terminal. At the terminal, we set up the state transition models and observation models. According to them, several recursive Bayesian algorithms are applied to producing position estimations. As shown in the experiments, all of three algorithms do not require constant moving speed and perform better than standalone ToA system or standalone IMU system. And within them, two algorithms can be applied for the tracking on any path which is not restricted by the requirement that the trajectory between the positions at two consecutive time steps is a straight line. 展开更多
关键词 indoor localization time of arrival (ToA) inertial measurement unit (IMU) Bayesian filter extended Kalman filter MAP algorithm
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Global localization of in-pipe robot based on ultra-long wave antenna array and global position system 被引量:4
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作者 齐海铭 Zhang Xiaohua +2 位作者 Chen Hongjun Sun Dongchang Sun Yongtai 《High Technology Letters》 EI CAS 2009年第2期120-125,共6页
A global localization system of in-pipe robot is introduced in this paper.Global position system(GPS)is applied to monitor the motion of robot along the whole pipeline which is equally divided intomany segments by tra... A global localization system of in-pipe robot is introduced in this paper.Global position system(GPS)is applied to monitor the motion of robot along the whole pipeline which is equally divided intomany segments by tracking stations.The definite segment in which robot existing can be detected and thisis long-range localization.Ultra-long wave(ULW)is adopted to solve the problem of metallic shieldingand realize effective communication between inside and outside of pipeline.ULW emitter is carried byrobot.When the plant is broken or defects on pipe-wall are inspected,the robot will stop moving.Anten-na array is presented and disposed upon the definite segment to search the accurate location of robot,andthis is short-range localization.In this paper,five-antenna array is adopted and an effective linear signalfusion algorithm is presented.The localization precision reaches R < 25cm.By tests in Shengli oil field,the whole system is verified with robust solutions. 展开更多
关键词 pipeline robot uhra-long wave (ULW) global localization antenna array signal fusion
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An efficient transient gene expression system for protein subcellular localization assay and genome editing in citrus protoplasts 被引量:2
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作者 Wenhui Yang Jiaqin Ren +6 位作者 Wanrong Liu Dan Liu Kaidong Xie Fei Zhang Pengwei Wang Wenwu Guo Xiaomeng Wu 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第3期425-436,共12页
Protoplast has been widely used in biotechnologies to circumvent the breeding obstacles in citrus, including long juvenility, polyembryony, and male/female sterility. The protoplast-based transient gene expression sys... Protoplast has been widely used in biotechnologies to circumvent the breeding obstacles in citrus, including long juvenility, polyembryony, and male/female sterility. The protoplast-based transient gene expression system is a powerful tool for gene functional characterization and CRISPR/Cas9 genome editing in higher plants, but it has not been widely used in citrus. In this study, the polyethylene glycol(PEG)-mediated method was optimized for citrus callus protoplast transfection, with an improved transfection efficiency of 68.4%. Consequently, the efficiency of protein subcellular localization assay was increased to 65.8%, through transient expression of the target gene in protoplasts that stably express the fluorescent organelle marker protein. The gene editing frequencies in citrus callus protoplasts reached 14.2% after transient expression of CRISPR/Cas9 constructs. We demonstrated that the intronic polycistronic tRNAgRNA(inPTG) genome editing construct was functional in both the protoplast transient expression system and epicotyl stable transformation system in citrus. With this optimized protoplast transient expression system, we improved the efficiency of protein subcellular localization assay and developed the genome editing system in callus protoplasts, which provides an approach for prompt test of CRISPR vectors. 展开更多
关键词 CITRUS Callus protoplast Transient transfection Subcellular localization Genome editing
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Passive Localization of Multiple Sources Using Joint RSS and AOA Measurements in Spectrum Sharing System 被引量:3
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作者 Kang Li Yutao Jiao +2 位作者 Yehui Song Jinghua Li Chao Yue 《China Communications》 SCIE CSCD 2021年第12期65-80,共16页
In spectrum sharing systems,locating mul-tiple radiation sources can efficiently find out the in-truders,which protects the shared spectrum from ma-licious jamming or other unauthorized usage.Com-pared to single-sourc... In spectrum sharing systems,locating mul-tiple radiation sources can efficiently find out the in-truders,which protects the shared spectrum from ma-licious jamming or other unauthorized usage.Com-pared to single-source localization,simultaneously lo-cating multiple sources is more challenging in prac-tice since the association between measurement pa-rameters and source nodes are not known.More-over,the number of possible measurements-source as-sociations increases exponentially with the number of sensor nodes.It is crucial to discriminate which measurements correspond to the same source before localization.In this work,we propose a central-ized localization scheme to estimate the positions of multiple sources.Firstly,we develop two computa-tionally light methods to handle the unknown RSS-AOA measurements-source association problem.One method utilizes linear coordinate conversion to com-pute the minimum spatial Euclidean distance sum-mation of measurements.Another method exploits the long-short-term memory(LSTM)network to clas-sify the measurement sequences.Then,we propose a weighted least squares(WLS)approach to obtain the closed-form estimation of the positions by linearizing the non-convex localization problem.Numerical re-sults demonstrate that the proposed scheme could gain sufficient localization accuracy under adversarial sce-narios where the sources are in close proximity and the measurement noise is strong. 展开更多
关键词 multiple sources localization passive lo-calization received signal strength(RSS) angle of ar-rival(AOA) measurements-source association
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Localization of pallets in warehouses using passive RFID system 被引量:2
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作者 周俊儒 张宏建 周洪亮 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期3017-3025,共9页
Warehouse operation has become a critical activity in supply chain. Position information of pallets is important in warehouse management which can enhance the efficiency of pallets picking and sortation. Radio frequen... Warehouse operation has become a critical activity in supply chain. Position information of pallets is important in warehouse management which can enhance the efficiency of pallets picking and sortation. Radio frequency identification(RFID) has been widely used in warehouse for item identifying. Meanwhile, RFID technology also has great potential for pallets localization which is underutilized in warehouse management. RFID-based checking-in and inventory systems have been applied in warehouse management by many enterprises. Localization approach is studied, which is compatible with existing RFID checking-in and inventory systems. A novel RFID localization approach is proposed for pallets checking-in. Phase variation of nearby tags was utilized to estimate the position of added pallets. A novel inventory localization approach combing angle of arrival(AOA) measurement and received signal strength(RSS) is also proposed for pallets inventory. Experiments were carried out using standard UHF passive RFID system. Experimental results show an acceptable localization accuracy which can satisfy the requirement of warehouse management. 展开更多
关键词 warehouse management radio frequency identification (RFID) localIZATION tag phase
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LOCALIZED NODAL SOLUTIONS FOR SCHRODINGER-POISSON SYSTEMS 被引量:2
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作者 Xing WANG Rui HE Xiangqing LIU 《Acta Mathematica Scientia》 SCIE CSCD 2022年第5期1947-1970,共24页
In this paper,we study the existence of localized nodal solutions for Schrodinger-Poisson systems with critical growth{−ε^(2)Δv+V(x)v+λψv=v^(5)+μ|v|^(q−2)v,in R^(3),−ε^(2)Δψ=v^(2),in R^(3);v(x)→0,ψ(x)→0as|x... In this paper,we study the existence of localized nodal solutions for Schrodinger-Poisson systems with critical growth{−ε^(2)Δv+V(x)v+λψv=v^(5)+μ|v|^(q−2)v,in R^(3),−ε^(2)Δψ=v^(2),in R^(3);v(x)→0,ψ(x)→0as|x|→∞.We establish,for smallε,the existence of a sequence of localized nodal solutions concentrating near a given local minimum point of the potential function via the perturbation method,and employ some new analytical skills to overcome the obstacles caused by the nonlocal term φu(x)=1/4π∫R^(3)u^(2)(y)/|x−y|dy.Our results improve and extend related ones in the literature. 展开更多
关键词 Schrodinger-Poisson systems localized nodal solutions perturbation method
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