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Hybrid Passive/Active Vibration Control of a Loosely Connected Spacecraft System 被引量:3
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作者 Xin Wang Xiaokui Yue +1 位作者 Haowei Wen Jianping Yuan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第1期61-87,共27页
In this paper,a hybrid passive/active vibration(HPAV)controller of a loosely connected spacecraft consisting of a servicing satellite,a target and an X-shape structure isolator is first proposed to suppress vibrations... In this paper,a hybrid passive/active vibration(HPAV)controller of a loosely connected spacecraft consisting of a servicing satellite,a target and an X-shape structure isolator is first proposed to suppress vibrations of the system when subjected to the impulsive external excitations during the on-orbit missions.The passive dynamic response of the combined system can be adjusted appropriately to achieve the desired vibration isolation performance by tuning the structural parameters of the bio-inspired X-shape structure.Moreover,the adaptive control design through dynamic scaling technique is selected as the active component to maintain high vibration isolation performance in the presence of parameter uncertainties such as mass of the satellite platform,the damping and rotation friction coefficients of the X-shape structure.Compared with the pure passive system and the traditional spring-mass-damper(SMD)isolator,the HPAV strategy witnesses lower transmissibility,smaller vibration amplitude and higher convergence rate when subjected to the post-capture impact.Numerical simulations demonstrate the feasibility and validity of the proposed hybrid control scheme in suppressing vibrations of the free-floating spacecraft. 展开更多
关键词 Hybrid passive/active vibration control X-shape structure adaptive control on-orbit capture
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A multi-mode thermoregulating fabric with integrated passive/active temperature control capabilities
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作者 Jingwen Dong Bing Zhou +5 位作者 Gaojie Han Jin Gao Xianhu Liu Yuezhan Feng Chuntai Liu Changyu Shen 《Nano Research》 2025年第10期1043-1053,共11页
Wearable thermoregulating fabrics with multi-mode temperature control are of great significance in response to extreme cold weather.Herein,a multi-mode thermoregulating thermoplastic polyurethane(TPU)/MXene fabric(TMF... Wearable thermoregulating fabrics with multi-mode temperature control are of great significance in response to extreme cold weather.Herein,a multi-mode thermoregulating thermoplastic polyurethane(TPU)/MXene fabric(TMF),integrating passive radiation/thermal insulation and active Joule/solar heating,was fabricated via simultaneous electrospinning and electrospraying.The TPU/MXene fabric exhibits passive radiation/thermal insulation performance due to the low infrared emissivity of MXene and the unique porous structure of electrospun membrane,which could prevent human heat loss through radiation and convection.Moreover,the MXene network allows for ideal electrical conductivity(1280 S·m^(−1))and high solar absorption(~93%),thus endowing the TMF with active Joule/solar heating capabilities that can intelligently warm the body in cold environments.In actual tests,the synergistic effect of passive insulation and active heating could improve skin temperature by up to 8.7–10.9℃,which is much higher than passive insulation alone(4.0℃).Additionally,the MXene conductive network provides effective electromagnetic interference(EMI)shielding ability for the thermoregulating fabric,which can be readily adjusted from 38 to 105 dB by stacking the fabric.This issue emphasizes the significant potential of multi-mode thermoregulatory fabric featuring adjustable EMI shielding for future wearable technology. 展开更多
关键词 thermoplastic polyurethane(TPU)/MXene fabric human thermal protection passive insulation active heating electromagnetic interference(EMI)shielding
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Mechanisms of Targeted Drug Delivery for Liver Cancer: Active, Passive, and Subcellular Strategies
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作者 Yang Tian Yusheng Shi 《Journal of Biosciences and Medicines》 2025年第2期369-384,共16页
This article provides a comprehensive review of various approaches to targeted drug delivery for liver cancer, an area of significant need due to the limited effectiveness of current treatments. The article begins by ... This article provides a comprehensive review of various approaches to targeted drug delivery for liver cancer, an area of significant need due to the limited effectiveness of current treatments. The article begins by highlighting the role of the liver in metabolism and discusses the high mortality associated with hepatocellular carcinoma (HCC). The shortcomings of traditional chemotherapy, such as multidrug resistance and off-target effects, necessitate the exploration of novel therapeutic strategies, with a focus on targeted approaches. The review details both passive and active targeting strategies. Passive targeting leverages the enhanced permeability and retention (EPR) effect and unique features of the tumor microenvironment, while active targeting employs specific ligands, such as peptides, antibodies, and proteins, to bind to overexpressed receptors on liver and tumor cells. The article further details many examples of active targeting using the asialoglycoprotein receptor (ASGPR), glycyrrhetinic acid (GA), transferrin receptor (TfR), and folate receptor (FR) on hepatocytes and tumor cells, demonstrating that there has been significant research effort put into this field. The importance of non-parenchymal cells in the liver is also discussed, and the article examines methods of targeting Kupffer cells, sinusoidal endothelial cells, and hepatic stellate cells for therapeutic benefit. The review goes on to cover the emerging field of subcellular targeting, including specific strategies to target the nucleus, mitochondria, and the endoplasmic reticulum/Golgi apparatus, noting that although there has been some progress, further research is needed in this area. The text finishes with a summary which acknowledges that while targeted therapies, including enzyme-activated prodrugs, such as Pradefovir, and other novel methods for drug delivery have shown significant promise, challenges remain in translating these therapies into clinical use due to limitations in understanding the sequential transport and the mechanisms of action. Ultimately, the article emphasizes the need for in-depth research to fully realize the potential of precision cancer therapies for liver cancer. 展开更多
关键词 Targeted Drug Delivery Hepatocellular Carcinoma (HCC) active Targeting Subcellular Targeting NANOMEDICINE
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Biodegradable Mg-based medical devices:From passive support to active modulation
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作者 Lin Mao Zhongxin Hu Chengli Song 《Journal of Magnesium and Alloys》 2025年第10期4795-4816,共22页
Biodegradable magnesium(Mg)-based medical devices have revolutionized medical implants by uniquely combining biocompatibility and mechanical strength.Fully degradable Mg-based implants have been developed to provide t... Biodegradable magnesium(Mg)-based medical devices have revolutionized medical implants by uniquely combining biocompatibility and mechanical strength.Fully degradable Mg-based implants have been developed to provide temporary structural support and serve as a dynamic scaffold for tissue repair and restructuring.Additionally,Mg-based devices can respond to physiological signals,and their integration with electrical currents or pulses has been explored to enhance tissue healing and functional recovery.This review provides a comprehensive overview of the development and application of Mg-based medical devices,highlighting their evolution from traditional orthopedic,vascular,and dental uses to advanced systems that actively modulate physiological processes—a shift from passive support to active modulation.The application range of Mg-based devices has expanded from early vascular sutures,bone screws,and stents to multiple clinical fields including porous bone repair scaffolds,anastomotic staples,bioactive devices,and electro-active systems.Bioactive Mg devices demonstrate therapeutic properties including antibacterial,anti-inflammatory,anti-tumor,and osteogenic functions through their degradation products,while electro-active devices utilize the electrical properties of Mg for sensing,monitoring,and therapeutic stimulation.Finally,this review highlights current challenges,including maintaining mechanical support performance,optimizing control of biochemical reactions,and balancing electroregulatory functions,and identifies future research directions aimed at enhancing the clinical application of biodegradable Mg-based implants,thereby contributing to the significant advancement in the biomedical field. 展开更多
关键词 Mg alloy BIODEGRADATION Medical device Tissue scaffold active modulation
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Stabilizing 459 nm passive optical clock for pumping 1470 nm active optical clock
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作者 Haoyang Wu Zhiqiang Wen +4 位作者 Chen Wang Zhenfeng Liu Jingbiao Chen Shougang Zhang Deshui Yu 《Chinese Physics B》 2025年第11期170-178,共9页
Optical clocks with thermal atoms are characterized by compact size,simple structure,reduced weight,and low power consumption and have the potential for broad out-of-the-lab and commercial applications.Here,we demonst... Optical clocks with thermal atoms are characterized by compact size,simple structure,reduced weight,and low power consumption and have the potential for broad out-of-the-lab and commercial applications.Here,we demonstrate a 459 nm optical clock based on the 6S_(1/2)-7P_(1/2)transition in thermal^(133)Cs atoms.Two methods,modulation transfer spectroscopy(MTS)and frequency modulation spectroscopy(FMS),are employed to stabilize the frequency of a 459 nm commercial laser to the atomic transition.The MTS-MTS and MTS-FMS beat-note measurements show short-term frequency stabilities of 3.7×10^(-13)/√t and 6.4×10^(-13)/√t,respectively,at the averaging time t.The 459 nm passive optical clock further serves as the pump for an active 1470 nm optical clock based on the cavityless lasing.The resultant 1470 nm output power reaches over 10μW and the pump-beam-induced light shift is estimated to be 2π×11 Hz with a fractional uncertainty of 2.4×10^(-18).These results demonstrate the feasibility of hybridizing passive and active optical clocks,providing a promising route toward compact multi-wavelength optical frequency standards. 展开更多
关键词 modulation transfer spectroscopy frequency modulation spectroscopy active optical clocks
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Passive-source multitaper-spectral method based low-frequency data reconstruction for active seismic sources 被引量:3
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作者 张盼 韩立国 +2 位作者 周岩 许卓 葛奇鑫 《Applied Geophysics》 SCIE CSCD 2015年第4期585-597,629,630,共15页
Passive seismic data contain large amounts of low-frequency information. To effectively extract and compensate active seismic data that lack low frequencies, we propose a multitaper spectral reconstruction method base... Passive seismic data contain large amounts of low-frequency information. To effectively extract and compensate active seismic data that lack low frequencies, we propose a multitaper spectral reconstruction method based on multiple sinusoidal tapers and derive equations for multisource and multitrace conditions. Compared to conventional cross correlation and deconvolution reconstruction methods, the proposed method can more accurately reconstruct the relative amplitude of recordings. Multidomain iterative denoising improves the SNR of retrieved data. By analyzing the spectral characteristics of passive data before and after reconstruction, we found that the data are expressed more clearly after reconstruction and denoising. To compensate for the low-frequency information in active data using passive seismic data, we match the power spectrum, supplement it, and then smooth it in the frequency domain. Finally, we use numerical simulation to verify the proposed method and conduct prestack depth migration using data after low-frequency compensation. The proposed power-matching method adds the losing low frequency information in the active seismic data using the low-frequency information of passive- source seismic data. The imaging of compensated data gives a more detailed information of deep structures. 展开更多
关键词 passive source multitaper spectral reconstruction low-frequency compensation power matching
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Passive activity enhances residual control ability in patients with complete spinal cord injury 被引量:2
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作者 Yanqing Xiao Mingming Gao +6 位作者 Zejia He Jia Zheng Hongming Bai Jia-Sheng Rao Guiyun Song Wei Song Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS 2025年第8期2337-2347,共11页
Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these... Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface electromyography.In this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord injury.Eleven patients with chronic complete thoracic spinal cord injury were recruited.Surface electromyography data from eight major leg muscles were acquired and compared before and after the passive activity protocol.The results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of activation.Although the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically significant.These findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury. 展开更多
关键词 complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task
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Comparative Risk of Stroke Associated with Active Smoking in Chinese and Asian Populations
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作者 Zemin Cai Xiaojing Guo +3 位作者 Xiao Zhang Danying Li Xiaoyue Li Xia Wan 《Biomedical and Environmental Sciences》 2026年第1期60-72,共13页
Objective Stroke is the third leading cause of death worldwide,with the highest incidence in Asia,particularly in China,where smoking remains a major risk factor.The smoking prevalence in China is similar to that in A... Objective Stroke is the third leading cause of death worldwide,with the highest incidence in Asia,particularly in China,where smoking remains a major risk factor.The smoking prevalence in China is similar to that in Asia.Whether the risk estimates for smoking-related stroke in China and all Asian countries are still unknown which is worth evaluating.Thus,this study aims to compare the Relative Risk(RR)of smoking-attributed stroke among the Chinese and Asian populations.Methods A literature search was conducted from the inception to September 10,2022.Studies meeting the criteria were included.The articles were screened,and related information was extracted.Pooled RRs stratified by smoking status and sex were analyzed,including subgroup analyses for China,other Asian countries,and Asia overall.Finally,publication bias and sensitivity analyses were conducted.Results Thirty-seven articles on the Chinese population and 15 on other Asian populations were included,with a mean Newcastle-Ottawa scale(NOS)score of 7.25.About ever smokers,there had no statistical difference existed in both sexes and females between China and other Asian countries,while the RR of males in other Asian countries[2.31(1.38,3.86)]was higher than that in China[1.21(1.15,1.26)];further subgroup analysis indicated that other Asian countries had higher RR[3.76(3.02,4.67)]in the morbidity subgroup.The RRs of both sexes,males and females,between China and the whole of Asia were not statistically different.As for current and former smokers,no meaningful statistical difference was observed in the pooled RRs of both sexes,males and females,in China,other Asian countries,and all of Asia.Conclusion The RR of males ever smokers in China was smaller than that in other Asian countries due to the few articles of morbidity subgroup,but had no statistical difference with the whole of Asia;other groups of ever smokers,current smokers,and former smokers were not statistically significant with other Asian countries or the whole of Asia. 展开更多
关键词 active smoking STROKE China Asian countries META-ANALYSIS
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Active optical waveguides and metal ion sensors based on nanofibers with aggregation induced emission
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作者 Liping Xu Xianguang Yang +9 位作者 Ming Chen Kai Li Junda He Dehua Tian Zaizhu Lou Fangchang Tan Puxiang Lai Andrea Camposeo Dario Pisignano Baojun Li 《Nano Research》 2026年第1期1077-1088,共12页
Fiber-structured ion sensors have gained traction in health monitoring and medical diagnostics owing to their structural flexibility,enhanced sensitivity,and suitability for integration into wearable devices.This stud... Fiber-structured ion sensors have gained traction in health monitoring and medical diagnostics owing to their structural flexibility,enhanced sensitivity,and suitability for integration into wearable devices.This study employed a simple and efficient solutionbased process to fabricate nanofibers containing aggregation-induced emission(AIE)dyes.The resulting AIE nanofibers exhibited stable and intense fluorescence,nanosecond fluorescence lifetime,and low-loss light transport when functioning as active waveguides.Additionally,crossed nanofiber intersections exhibited diffraction-limited emission spots.The AIE nanofibers demonstrate efficient and ionspecific fluorescence quenching in response to Ag^(+).These results support the development of sensing units capable of operating in liquid environments or in direct contact with skin or tissues,facilitating real-time monitoring of ion concentrations for personalized healthcare management. 展开更多
关键词 aggregation-induced emission NANOFIBERS fluorescence lifetime active waveguide ion sensors
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A review of the pharmacology of active ingredients in Ginseng Radix et Rhizoma(Renshen)anti-aging
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作者 Tian-Yuan Liu Jin-Ning Chang +6 位作者 Xiao-Wei Dai Hao-Xin Ma Wei-Jia Chen Rui Du Akmal Muhammad Jian-Ming Li Zhong-Mei He 《Traditional Medicine Research》 2026年第3期65-76,共12页
Population aging is one of the common challenges in the current world.As people age,the body’s tissues including cells,and molecules inevitably degrade,and their functions gradually decline,causing various age-relate... Population aging is one of the common challenges in the current world.As people age,the body’s tissues including cells,and molecules inevitably degrade,and their functions gradually decline,causing various age-related diseases like Alzheimer’s disease,osteoporosis,low immunity,glucose and lipid metabolism disorders,and cardiovascular diseases.With the continuous increase of the elderly population,the pressure on the medical industry is increasing.To lower the burden on the medical industry and increase the average age of the elderly,it is vital to explore effective anti-aging materials.Ginseng Radix et Rhizoma(Renshen),as a traditional and precious Chinese medicinal herb,is known as the“king of all herbs”.It is famous for its effects of“tonifying Qi,restoring pulse”(helping with the generation of Qi(the fundamental,vital energy that continuously flows within the body)and the circulation of blood)and strengthening the body,nourishing the spleen and lungs,generating fluids and nourishing blood,calming the mind and improving intelligence.Recently,its anti-aging effect has received increasing attention from modern scientific research.This study summarizes the pharmacological effects of the main active ingredients of Renshen(ginsenosides,polysaccharides,etc.)on resisting aging,including preventing neuroaging,suppressing skin aging,mitigating ovarian aging,inhibiting osteoporosis and arthritis,enhancing the immune system of the elderly,protecting the cardiovascular system,resisting aging-induced fatigue and exerting the anti-tumor effects.Through network pharmacology and molecular docking,the anti-aging active ingredients of Renshen were screened,and the key targets and pathways of anti-aging active ingredients in Renshen were determined.Using network pharmacology,totally 106 drug targets and 3,479 disease targets were screened,and 79 common targets between aging and Renshen were identified.Three core targets were identified in the PPI network,including TNF,AKT1,and IL-1β.Molecular docking was used to obtain further verification.This study emphasizes the potential of Renshen as a source of anti-aging activity,which can be developed into a novel drug for the treatment of age-related diseases. 展开更多
关键词 Renshen active ingredients ANTI-AGING pharmacological effects network pharmacology molecular docking
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Early intelligent active assistance in walking for hemiplegic patients under suspension protection: a randomized controlled trial
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作者 Ma Shanxin Zheng Jianling +5 位作者 Cheng Jian Lin Xi Li Qiuyuan Wang Li Zeng Yangkang Song Luping 《中国组织工程研究》 北大核心 2026年第12期3075-3082,共8页
BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking rec... BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking recovery.OBJECTIVE:To determine whether early suspension-protected training with a personal assistant machine for stroke patients enhances walking ability and prevents muscle spasms.METHODS:Thirty-two early-stage stroke patients from Shenzhen University General Hospital and the China Rehabilitation Research Center were randomly assigned to the experimental group(n=16)and the control group(n=16).Both groups underwent 4 weeks of gait training under the suspension protection system for 30 minutes daily,5 days a week.The experimental group used the personal assistant machine during training.Three-dimensional gait analysis(using the Cortex motion capture system),Brunnstrom staging,Fugl-Meyer Assessment for lower limb motor function,Fugl-Meyer balance function,and the modified Ashworth Scale were evaluated within 1 week before the intervention and after 4 weeks of intervention.RESULTS AND CONCLUSION:After the 4-week intervention,all outcome measures showed significant changes in each group.The experimental group had a small but significant increase in the modified Ashworth Scale score(P<0.05,d=|0.15|),while the control group had a large significant increase(P<0.05,d=|1.48|).The experimental group demonstrated greater improvements in walking speed(16.5 to 38.44 cm/s,P<0.05,d=|4.01|),step frequency(46.44 to 64.94 steps/min,P<0.05,d=|2.32|),stride length(15.50 to 29.81 cm,P<0.05,d=|3.44|),and peak hip and knee flexion(d=|1.82|to|2.17|).After treatment,the experimental group showed significantly greater improvements than the control group in walking speed(38.44 vs.26.63 cm/s,P<0.05,d=|2.75|),stride length,peak hip and knee flexion(d=|1.31|to|1.45|),step frequency(64.94 vs.59.38 steps/min,P<0.05,d=|0.85|),and a reduced support phase(bilateral:24.31%vs.28.38%,P<0.05,d=|0.88|;non-paretic:66.19%vs.70.13%,P<0.05,d=|0.94|).For early hemiplegia,personal assistant machine-assisted gait training under the suspension protection system helps establish a correct gait pattern,prevents muscle spasms,and improves motor function. 展开更多
关键词 hemiplegia stroke suspension protection system personal assistant machine intelligent walking aid early rehabilitation active training walking function NEUROPLASTICITY gait analysis motor function recovery rehabilitation training balance ability
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HPR1000: Advanced Pressurized Water Reactor with Active and Passive Safety 被引量:33
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作者 Ji xing Daiyong Song Yuxiang Wu 《Engineering》 SCIE EI 2016年第1期79-87,共9页
HPR1000 is an advanced nuclear power plant(NPP)with the significant feature of an active and passive safety design philosophy,developed by the China National Nuclear Corporation.On one hand,it is an evolutionary desig... HPR1000 is an advanced nuclear power plant(NPP)with the significant feature of an active and passive safety design philosophy,developed by the China National Nuclear Corporation.On one hand,it is an evolutionary design based on proven technology of the existing pressurized water reactor NPP;on the other hand,it incorporates advanced design features including a 177-fuel-assembly core loaded with CF3 fuel assemblies,active and passive safety systems,comprehensive severe accident prevention and mitigation measures,enhanced protection against external events,and improved emergency response capability.Extensive verification experiments and tests have been performed for critical innovative improvements on passive systems,the reactor core,and the main equipment.The design of HPR1000fulfills the international utility requirements for advanced light water reactors and the latest nuclear safety requirements,and addresses the safety issues relevant to the Fukushima accident.Along with its outstanding safety and economy,HPR1000 provides an excellent and practicable solution for both domestic and international nuclear power markets. 展开更多
关键词 HPRI000 active and passive safety Advanced nuclear power reactor
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UKF-based multi-sensor passive tracking with active assistance 被引量:21
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作者 Li Anping Jing Zhongliang Hu Shiqiang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第2期245-250,共6页
A new synergy tracking method of infrared and radar is presented. To improve tracking accuracy, the unscented Kalman filter (UKF), which has better nonlinear approximation ability, is adopted. In addition, to reduce... A new synergy tracking method of infrared and radar is presented. To improve tracking accuracy, the unscented Kalman filter (UKF), which has better nonlinear approximation ability, is adopted. In addition, to reduce the possibility of radar being locked-on by adverse electronic support measure (ESM), radar is under the intermittent-working state. After radar is turned off, the possible target position is estimated by a set of time polynomials, which is constructed based on the sufficient observations done before radar is turned off, the estimated values from time polynomials are compared with the current observation values from infrared to determine the time when radar is turned on. Simulation results show the method has a good tracking accuracy and effectively reduces the possibility of radar being locked-on by adverse ESM. 展开更多
关键词 active radar INFRARED least square time polynomial the unscented Kalman filter.
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Effects of active and passive training apparatus combined with rehabilitation training on lower limb function of stroke patients during recovery period 被引量:1
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作者 Yang Tian Lanfang Shi +3 位作者 Lei Jing Le Li Bin Chen Ke wei Zhao 《Neural Regeneration Research》 SCIE CAS CSCD 2007年第10期636-640,共5页
Stroke patients always spontaneously do some learning and training of motor functions; however, learning and training are not prompt and right, while patients do not have enough activity amounts. Active and passive mo... Stroke patients always spontaneously do some learning and training of motor functions; however, learning and training are not prompt and right, while patients do not have enough activity amounts. Active and passive motor training apparatus is aimed directly at lower limb training so as to stimulate nerve function through stimulating muscular movement. Based on motor mileage, motor time, various power supplies and velocity of active and passive training apparatus, we can understand the training condition and adjust training program. OBJECTIVE: To observe the effects of grade-III rehabilitation training combining with active and passive training apparatus on lower limb function, muscle strength and activity of daily living (ADL) in stroke patients during recovery period. DESIGN: Contrast observation. SETTING: Department of Rehabilitation, Jilin Academic Institute of Traditional Chinese Medicine. PARTICIPANTS: A total of 80 patients with stroke-induced hemiplegia after stabilizing vital signs for 2 weeks were selected from Department of Rehabilitation, Jilin Academic Institute of Traditional Chinese Medicine from January to June 2007. There were 47 males and 33 females, and their ages ranged from 41 to 75 years. All patients met the diagnostic criteria of the Fourth National Cerebrovascular Disease Academic Meeting in 1995 and were diagnosed as cerebral hemorrhage or cerebral infarction through CT or MRI examinations in clinic. Patients and their parents provided the confirmed consent. Based on therapeutic orders of hospitalization, patients were randomly divided into treatment group and control group with 40 patients in each group. METHODS: Patients in the control group received physical therapy and occupational therapy combining with rehabilitative treatment based on grade-III rehabilitative treatment program, which was set by the National Cerebrovascular Disease Topic Group. In addition, patients in the treatment group were trained with active and passive motor training apparatus based on therapeutic procedures in the control group. The active and passive motor training apparatus was designed as the therapeutic style of nervous system; otherwise, the treatment was performed once a day, 30 minutes once and 6 times per week. Four weeks were regarded as a course. MAIN OUTCOME MEASURES: Before treatment, at 2 weeks after treatment and after the first course, bare-handed muscle strength examination was used to check muscle strength and muscular tension; in addition, simple Fugl-Meyer assessment (FMA) and diagnostic criteria which were set by the Fourth National Cerebrovascular Disease Academic Meeting were used to evaluate motor function of limbs and total ADL. RESULTS: All 80 stroke patients were involved in the final analysis. ① Muscle strength of lower limbs was improved in both treatment group and control group. After the first course, muscle strength in the treatment group was obviously superior to that in the control group ( x^2=6.64, P 〈 0.05). ② After the first course, Fugl-Meyer scores in the treatment group were higher than those in the control group, and there was significant difference (t =2.82, P 〈 0.05). ③ Muscular tension of lower limbs was not changed in both treatment group and control group after treatment (P 〉 0.05). ④ After the first course, ADL in the treatment group was superior to that in the control group (P 〈 0.05). Among patients in the treatment group, 24 cases (60%) had obvious progress, 16 (40%) had progress, and 0 (0%) did not have any changes. On the other hand, among patients in the control group, 13 cases (32.5%) had obvious progress, 26 (65%) had progress, and 1 (2.5%) did not have any changes. CONCLUSION: Rehabilitation training combining with active and passive motor training apparatus can promote the recovery of lower limb disorder, increase muscle strength, control spasm, improve ADL and cause satisfactorily clinical effects in stroke patients during recovery period. 展开更多
关键词 active and passive training apparatus STROKE HEMIPLEGIA rehabilitation training
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Detection efficiency characteristics of free-running InGaAs/InP single photon detector using passive quenching active reset IC 被引量:1
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作者 郑福 王超 +1 位作者 孙志斌 翟光杰 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第1期460-464,共5页
InGaAs/InP avalanche photodiodes (APD) are rarely used in a free-running regime for near-infrared single photon detection. In order to overcome the detrimental afterpulsing, we demonstrate a passive quenching active... InGaAs/InP avalanche photodiodes (APD) are rarely used in a free-running regime for near-infrared single photon detection. In order to overcome the detrimental afterpulsing, we demonstrate a passive quenching active reset integrated circuit. Taking advantage of the inherent fast passive quenching process and active reset to reduce reset time, the integrated circuit is useful for reducing afterpulses and is also area-efficient. We investigate the free-running single photon detector's afterpulsing effect, de-trapping time, dark count rate, and photon detection efficiency, and also compare with gated regime operation. After correction for deadtime and afterpulse, we find that the passive quenching active reset free-running single photon detector's performance is consistent with gated operation. 展开更多
关键词 single photon detector free-running passive quenching active reset
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Effectiveness of a 12-Week Program of Active and Passive Stretching in Improving Low Back and Neck Pain in Japanese Sedentary Men 被引量:1
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作者 Yuna Naraoka Mikiyuki Katagiri Takuji Shirasawa 《Health》 2017年第3期493-505,共13页
Purpose: Muscle stretching is frequently prescribed in physical therapy to manage lower back and neck pain. However, there is no clear evidence regarding the differences in effectiveness of active and passive stretchi... Purpose: Muscle stretching is frequently prescribed in physical therapy to manage lower back and neck pain. However, there is no clear evidence regarding the differences in effectiveness of active and passive stretching. Therefore, we aimed to evaluate the relative effectiveness of a 12-week program of active and passive stretching on selected physical and mental stress variables of sedentary men with lower back and neck pain. Methods: A cohort of 28 sedentary men, 30 - 49 years old, were divided into two intervention groups: the passive stretching group (PSG, n = 15) and the active stretching group (ASG, n = 13). A trainer assisted with static passive stretching, while participants in the ASG were provided with an instructional video. The following outcomes were measured at the start and end of the first and twelfth week of the stretching program: physical measures (visual analogue scale score of lower back and neck pain;finger-to-floor distance, gravimetric assessment of pelvic tilt, muscle hardness of the biceps femoris, and straight-leg raising) and mental stress measures (α-amylase and cortisol levels in saliva samples). Results: Although both active and passive stretching produced acute changes in lower back and neck pain, only passive stretching yielded long-term improvement in pain, finger-to-floor distance, pelvic tilt, hardness of biceps femoris muscle and cortisol levels (p Conclusion: Passive stretching is superior to active stretching in reducing pain, increasing muscle extensibility and correcting posture among a group of sedentary men with lower back and neck pain. 展开更多
关键词 active STRETCHING passive STRETCHING Lower Back PAIN Neck PAIN
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Active and passive compliant force control of ultrasonic surface rolling process on a curved surface 被引量:2
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作者 Kaiming ZHANG Ji WANG +2 位作者 Yixin LIU Shuang LIU Xiancheng ZHANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第7期289-299,共11页
Ultrasonic surface rolling process(USRP)is one of the effective mechanical surface enhancement techniques.During the USRP,unstable static force will easily do harm to the surface quality.In order to achieve a higher s... Ultrasonic surface rolling process(USRP)is one of the effective mechanical surface enhancement techniques.During the USRP,unstable static force will easily do harm to the surface quality.In order to achieve a higher surface quality on the part with a curved surface,an active and passive compliant USRP system has been developed.The compliant USRP tool can produce the natural obedience deformation along the part surface.Force control based on the fuzzy Proportional-integral-derivative(PID)method is then designed to maintain the static force during the USRP.Experiments have been performed on a real aero-engine blade with curved surface.It is proved that the deigned active and passive compliant USRP system can significantly reduce the force variation from 42.2 N to 4.2 N,and achieve a uniform surface quality after processing. 展开更多
关键词 active and passive compliant Curved surface Force control Surface integrity Ultrasonic surface rolling process
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Design approaches for active,semi-active and passive control systems based on analysis of characteristics of active control force 被引量:4
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作者 Ou Jinping Li Hui 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第4期493-506,共14页
In this paper, the characteristics of forces in active control systems connected to adjacent levels of a building are analyzed. The following characteristics are observed: (1) active control can provide significant... In this paper, the characteristics of forces in active control systems connected to adjacent levels of a building are analyzed. The following characteristics are observed: (1) active control can provide significantly superior supplemental damping to a building, but causes a small frequency shift; (2) the linear quadratic regulator (LQR)-based control force is composed of an elastic restoring force component and a damping force component, where the damping force is almost identical to the total control force, however, the elastic restoring force is very small; and (3) the active control forces prevent mction most of the time during the entire control process. These three characteristics imply that active control systems connected to adjacent levels of a building behave like passive damping devices with adjustable parameters, namely damping characteristics in an active control, which is the mechanism used by semi-active control devices to reach similar performance as active control systems. Two indices are defined to quantify the damping characteristics of control forces in active control systems. These two indices can also be used to quantify the capacity of semi-active control to achieve the perfonrlance of active control. Based on the above observations, two principles are founded for optimization of parameters of semi-active control devices and passive dampers. The first is that the maximum output force of a semi-active or passive device to be designed is identical to an active device, called "design principle". The other is the response equivalent principle, which states that the response of a building with semi-active or passive devices is the same as with active devices when the same maximum output force is applied. The design procedure for semi-active control devices and passive dampers is described in detail. Finally, numerical simulations of two benchmark problems is conducted to demonstrate the damping characteristics of active control and investigate the capacity of semi-active control to achieve the same performance as active control. 展开更多
关键词 active control: semi-active control smart control DAMPING design approach
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Association between head-and-neck cancers and active and passive cigarette smoking 被引量:1
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作者 Yukiomi Kushihashi Yoshiyuki Kadokura +5 位作者 Syuhei Takiguchi Yoshiyuki Kyo Yoshihiro Yamada Miki Shino Masato Kano Harumi Suzaki 《Health》 2012年第9期619-624,共6页
Although there have been many reports on the toxicity of tobacco smoke, fewer studies have reported the relationship between the smoke and carcinogenesis of head-and-neck cancers. It is assumed that direct stimulation... Although there have been many reports on the toxicity of tobacco smoke, fewer studies have reported the relationship between the smoke and carcinogenesis of head-and-neck cancers. It is assumed that direct stimulations due to tobacco smoke, such as chemical and mechanical stimulations, strongly influence the epithelium of the nasal cavity, paranasal sinuses, pharynx, and larynx. We investigated the influence of active and passive cigarette smoking on head-and-neck cancers. The subjects were 283 head-and-neck cancer patients examined at the otolaryngology department of Showa University Northern Yokohama Hospital in a 9-year and 2-month period from April 2001 to June 2010, in whom the presence or absence of active and passive cigarette smoking could be confirmed in detail. The active and passive smoking rates and the Brinkman index were retrospectively investigated according to the primary cancer site, gender, and histopathological classification. The active and passive smoking rates were high (about 90%) in patients with hypopharyngeal, laryngeal, and cervical esophageal cancers, and the Brinkman index was high in all. Squamous cell carcinoma (SCC) patients accounted for a high ratio of the head-and-neck cancer patients, and the active and passive smoking rates were significantly higher in SCC than in non-squamous cell carcinoma (non-SCC) patients (p < 0.0003). The active and passive smoking rates and the Brinkman index were high in patients with head-and-neck cancers in regions receiving strong direct stimulation from tobacco smoke, and the Brinkman index was also high in these patients, suggesting that carcinogenesis of head-and-neck cancers is strongly influenced by direct tobacco smoke stimulation. 展开更多
关键词 Head-and-Neck CANCERS SQUAMOUS Cell Carcinoma active SMOKING RATE passive SMOKING RATE Brinkman Index
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Roughness correction method for salinity remote sensing using combined active/passive observations 被引量:1
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作者 Wentao Ma Guihong Liu +1 位作者 Yang Yu Yanlei Du 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第11期189-195,共7页
Roughness-induced emission from ocean surfaces is one of the main issues that affects the retrieval accuracy of sea surface salinity remote sensing.In previous studies,the correction of roughness effect mainly depende... Roughness-induced emission from ocean surfaces is one of the main issues that affects the retrieval accuracy of sea surface salinity remote sensing.In previous studies,the correction of roughness effect mainly depended on wind speeds retrieved from scatterometers or those provided by other means,which necessitates a high requirement for accuracy and synchronicity of wind-speed measurements.The aim of this study is to develop a novel roughness correction model of ocean emissivity for the salinity retrieval application.The combined active/passive observations of normalized radar cross-sections(NRCSs)and emissivities from ocean surfaces given by the L-band Aquarius/SAC-D mission,and the auxiliary wind directions collocated from the National Centers for Environmental Prediction(NCEP)dataset are used for model development.The model is validated against the observations and the Aquarius standard algorithms of roughness-induced emissivity correction.Comparisons between model computations and measurements indicate that the model has better accuracy in computing wind-induced brightness temperature in the upwind/downwind directions or for the surfaces with smaller NRCSs,which can be better than 0.3 K.However,for crosswind directions and larger NRCSs,the model accuracy is relatively low.A model using HH-polarized NRCSs yields better accuracy than that using VV-polarized ones.For a fair comparison to the Aquarius standard algorithms using wind speeds retrieved from multi-source data,the maximum likelihood estimation is employed to produce results combining our model calculations and those using other sources.Numerical simulations show that combined results basically have higher accuracy than the standard algorithms. 展开更多
关键词 salinity remote sensing roughness correction Aquarius satellite active/passive
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