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Hypoxic response elements and Tet-On advanced double-controlled systems regulate hVEGF_(165) and angiopoietin-1 gene expression in vitro 被引量:1
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作者 Hao Zhang Hongyan Dong +4 位作者 Bo Jiang Zheng Wang Rui Chen Zhifeng Zhang Zhongming Zhang 《The Journal of Biomedical Research》 CAS 2011年第3期204-212,共9页
Angiogenesis in ischemic tissue is a complex and multi-gene event. In the study, we constructed hypoxic re-sponse elements (HRE) and the Tet-On advanced double-controlled systems and investigated their effects on th... Angiogenesis in ischemic tissue is a complex and multi-gene event. In the study, we constructed hypoxic re-sponse elements (HRE) and the Tet-On advanced double-controlled systems and investigated their effects on the expression of hVEGF165 and angiopoietin-1 (Ang-1) genes in rat cardiomyocytes exposed to hypoxia and pharma-cologic induction. We infected neonatal rat cardiomyocytes with recombinant rAAV-rtTA-Rs-M2/rAAV-TRE-Tight-Ang-1 and rAAV-9HRE- hVEGF165. Our results indicated that the viral titer was 1×1012 vg /mL and the viral purity exceeded 98%. hVEGF165 expression was induced by hypoxia, but not by normoxia (P 0.001). Ang-1 expression was evident under doxycycline induction, but undetectable without doxycycline induction (P 0.001). Immunofluorescence staining showed that positively stained hVEGF165 and Ang-1 protein appeared only under both hypoxia and doxycycline induction. We demonstrate here that HRE and the recombinant Tet-On advanced double gene-controlled systems sensitively regulate the expression of hVEGF165 and Ang-1 genes in an altered oxygen environment and under pharmacological induction in vitro. 展开更多
关键词 gene control vascular endothelial growth factor ANGIOPOIETIN-1 hypoxia DOXYCYCLINE CARDIOMYOCYTE
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Time-delay identification for linear controlled systems
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作者 Yiqiang Sun Hanwen Song Jian Xu 《Theoretical & Applied Mechanics Letters》 CAS 2013年第6期51-54,共4页
A new approach for time-delay identification is proposed in linear controlled systems. The delay is derived from the control loop in the system. The frequency-response function of the system is presented in terms of t... A new approach for time-delay identification is proposed in linear controlled systems. The delay is derived from the control loop in the system. The frequency-response function of the system is presented in terms of the impedance matrix. It is proved that the inverse form of the function may be expressed in the harmonic function, which is used to fit those data from the experiment. As an example, an isolator with the delayed feedback control is schemed to acquire such data. Using least square algorithm yields that the identified delay can reach any required accuracy. 展开更多
关键词 time-delay identification active control delayed isolator signal processing
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How completely are randomized controlled trials of non-pharmacological interventions following concussion reported? A systematic review
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作者 Jacqueline Josee van Ierssel Olivia Galea +8 位作者 Kirsten Holte Caroline Luszawski Elizabeth Jenkins Jennifer O’Neil Carolyn A Emery Rebekah Mannix Kathryn Schneider Keith Owen Yeates Roger Zemek 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第4期537-547,共11页
Purpose:The study aimed to examine the reporting completeness of randomized controlled trials(RCTs)of non-pharmacological interventions following concussion.Methods:We searched MEDLINE,Embase,PsycInfo,CINAHL,and Web o... Purpose:The study aimed to examine the reporting completeness of randomized controlled trials(RCTs)of non-pharmacological interventions following concussion.Methods:We searched MEDLINE,Embase,PsycInfo,CINAHL,and Web of Science up to May 2022.Two reviewers independently screened studies and assessed reporting completeness using the Template for Intervention Description and Replication(TIDieR),Consensus on Exercise Reporting Template(CERT),and international Consensus on Therapeutic Exercise aNd Training(i-CONTENT)checklists.Additional information was sought my study authors where reporting was incomplete.Risk of bias(ROB)was assessed with the Cochrane ROB-2 Tool.RCTs examining non-pharmacological interventions following concussion.Results:We included 89 RCTs(n=53 high ROB)examining 11 different interventions for concussion:sub-symptom threshold aerobic exercise,cervicovestibular therapy,physical/cognitive rest,vision therapy,education,psychotherapy,hyperbaric oxygen therapy,transcranial magnetic stimulation,blue light therapy,osteopathic manipulation,and head/neck cooling.Median scores were:TIDieR 9/12(75%;interquartile range(IQR)=5;range:5-12),CERT 17/19(89%;IQR=2;range:10-19),and i-CONTENT 6/7(86%;IQR=1;range:5-7).Percentage of studies completely reporting all items was TIDieR 35%(31/89),CERT 24%(5/21),and i-CONTENT 10%(2/21).Studies were more completely reported after publication of TIDieR(t_(87)=2.08;p=0.04)and CERT(t_(19)=2.72;p=0.01).Reporting completeness was not strongly associated with journal impact factor(TIDieR:rs=0.27;p=0.01;CERT:r_(s)=-0.44;p=0.06;i-CONTENT:r_(s)=-0.17;p=0.48)or ROB(TIDieR:rs=0.11;p=0.31;CERT:rs=0.04;p=0.86;i-CONTENT:rs=0.12;p=0.60).Conclusion:RCTs of non-pharmacological interventions following concussion demonstrate moderate to good reporting completeness,but are often missing key components,particularly modifications,motivational strategies,and qualified supervisor.Reporting completeness improved after TIDieR and CERT publication,but publication in highly cited journals and low ROB do not guarantee reporting completeness. 展开更多
关键词 CONCUSSION INTERVENTION Randomized controlled trial systematic review
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Mitophagy in acute central nervous system injuries:regulatory mechanisms and therapeutic potentials
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作者 Siyi Xu Junqiu Jia +2 位作者 Rui Mao Xiang Cao Yun Xu 《Neural Regeneration Research》 SCIE CAS 2025年第9期2437-2453,共17页
Acute central nervous system injuries,including ischemic stro ke,intracerebral hemorrhage,subarachnoid hemorrhage,traumatic brain injury,and spinal co rd injury,are a major global health challenge.Identifying optimal ... Acute central nervous system injuries,including ischemic stro ke,intracerebral hemorrhage,subarachnoid hemorrhage,traumatic brain injury,and spinal co rd injury,are a major global health challenge.Identifying optimal therapies and improving the long-term neurological functions of patients with acute central nervous system injuries are urgent priorities.Mitochondria are susceptible to damage after acute central nervous system injury,and this leads to the release of toxic levels of reactive oxygen species,which induce cell death.Mitophagy,a selective form of autophagy,is crucial in eliminating redundant or damaged mitochondria during these events.Recent evidence has highlighted the significant role of mitophagy in acute central nervous system injuries.In this review,we provide a comprehensive overview of the process,classification,and related mechanisms of mitophagy.We also highlight the recent developments in research into the role of mitophagy in various acute central nervous system injuries and drug therapies that regulate mitophagy.In the final section of this review,we emphasize the potential for treating these disorders by focusing on mitophagy and suggest future research paths in this area. 展开更多
关键词 autophagy intracerebral hemorrhage ischemic stroke mitochondria mitochondrial biogenesis mitochondrial quality control MITOPHAGY spinal cord injury subarachnoid hemorrhage traumatic brain injury
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A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury
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作者 Qi Liu Jianye Xie +5 位作者 Runxue Zhou Jin Deng Weihong Nie Shuwei Sun Haiping Wang Chunying Shi 《Neural Regeneration Research》 SCIE CAS 2025年第2期503-517,共15页
Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug deliv... Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury. 展开更多
关键词 angiogenesis biomaterial blood-brain barrier cerebral ischemia/reperfusion injury control release drug delivery inflammation QK peptides matrix metalloproteinase-2 NEUROPROTECTION self-assembling nanofiber hydrogel
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OPTIMUM CONTROL TO A PARTIALLY CONTROLLED TURBOGENERATOR SHAFT TORSIONAL VIBRATION SYSTEM 被引量:1
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作者 Hao Zhiyong Gao Wenzhi School of Mechanical Engineering,Tianjin University,Tianjin 300072,China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2002年第1期66-68,共3页
The optimal control to a partially controlled turbogenerator shaft torsionalvibration system is investigated. The principle of input feedforward control is presented to achievethe minimum of the average vibration ener... The optimal control to a partially controlled turbogenerator shaft torsionalvibration system is investigated. The principle of input feedforward control is presented to achievethe minimum of the average vibration energy in a system, and the optimal control matrix of thesystem is derived. A turbogenerator shaft system is taken as an example to simulate the optimalcontrol process of the torsional vibration. Results from this simulation indicate that the vibrationcan be effectively controlled by a partial control strategy. 展开更多
关键词 Optimal control Partially controlled system Torsional vibration TURBOGENERATOR
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Effect of Continuous Application of Controlled Release Nitrogen Fertilizer in Various Types of Soil in Dong-Ting Lake Region under Double Rice Cropping System
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作者 鲁艳红 廖育林 +3 位作者 聂军 谢坚 杨曾平 戴平安 《Agricultural Science & Technology》 CAS 2012年第2期351-356,379,共7页
[Objective] This study aimed to explore the effects of continuous application of controlled release nitrogen fertilizer under double rice cropping system. [Method] By modeling three types of paddy soils in Dong-Ting L... [Objective] This study aimed to explore the effects of continuous application of controlled release nitrogen fertilizer under double rice cropping system. [Method] By modeling three types of paddy soils in Dong-Ting Lake area, four treatments as no fertilizer (CK), urea, controlled release nitrogen fertilizer (CRNF) and 70% controlled release nitrogen fertilizer (70% CRNF) were designed in the micro-plot trials from 2005 to 2008. [Result] The rice yield in treatment CRNF at N 150 kg/hm2 was increased by 10.3%, 8.0% and 2.4% compared with treatment of urea, in alluvial sandy loamy paddy soil (ALS), purple calcareous clayey paddy soil (PCS), and reddish yellow loamy paddy soil (RYS), respectively; and the yield in treatment of 70% CRNF was increased by 6.1%, 2.6% and -0.8%, respectively. The ranking order of nitrogen uptake amount by plant in early rice and late rice was CRNF 70% CRNF urea CK in all three types of soil. Nitrogen utilization efficiency of CRNF in above three types of soil was 60.7%, 59.6% and 56.3%, increased by 23.8%, 19.4% and 16.3% compared with that in treatment of urea, respectively. Nitrogen utilization efficiency of CRNF in early rice was increased year by year, and was higher than that of 70% CRNF during the whole experiment stage, while that in late rice was increased first and then decreased from the 3rd year. [Conclusion] Continuous application CRNF could alleviate the decreasing of soil nitrogen fertility and organic carbon especially in ALS, increase rice yield and nitrogen utilization efficiency in double-rice cropping system. 展开更多
关键词 Double cropping rice controlled release nitrogen fertilizer Continuous fertilization YIELD Fertilizer use efficiency Soil fertility
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Hamiltonian Reduction of Quantum Systems Controlled by Pulses
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作者 徐强 王耀雄 +1 位作者 双丰 H.Rabitzc 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第4期378-382,I0003,共6页
We explores Hamiltonian reduction in pulse-controlled finite-dimensional quantum systems with near-degenerate eigenstates. A quantum system with a non-degenerate ground state and several near-degenerate excited states... We explores Hamiltonian reduction in pulse-controlled finite-dimensional quantum systems with near-degenerate eigenstates. A quantum system with a non-degenerate ground state and several near-degenerate excited states is controlled by a short pulse, and the objective is to maximize the collective population on all excited states when we treat all of them as one level. Two cases of the systems are shown to be equivalent to effective two-level systems. When the pulse is weak, simple relations between the original systems and the reduced systems are obtained. When the pulse is strong, these relations are still available for pulses with only one frequency under the first-order approximation. 展开更多
关键词 Quantum control Population transfer Laser pulse Dimension reduction
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Systematic review of randomised controlled trials:Probiotics for functional constipation 被引量:55
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作者 Anna Chmielewska Hania Szajewska 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第1期69-75,共7页
AIM:To systematically evaluate and update evidence on the efficacy and safety of probiotic supplementation for the treatment of constipation. METHODS:The MEDLINE,EMBASE,CINAHL,and Cochrane Library databases were searc... AIM:To systematically evaluate and update evidence on the efficacy and safety of probiotic supplementation for the treatment of constipation. METHODS:The MEDLINE,EMBASE,CINAHL,and Cochrane Library databases were searched in May 2009 for randomised controlled trials(RCTs)performed in paediatric or adult populations related to the study aim. RESULTS:We included five RCTs with a total of 377 subjects(194 in the experimental group and 183 in the control group).The participants were adults (three RCTs,n=266)and children(two RCTs,n= 111)with constipation.In adults,data suggests a favourable effect of treatment with Bifidobacterium lactis DN-173 010,Lactobacillus casei Shirota,and Escherichia coli Nissle 1917 on defecation frequency and stool consistency.In children,L.casei rhamnosusLcr35,but not L.rhamnosus GG,showed a beneficial effect. CONCLUSION:Until more data are available,we believe the use of probiotics for the treatment of constipation condition should be considered investigational. 展开更多
关键词 Randomised controlled trials CONSTIPATION PROBIOTICS ADULTS CHILDREN
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Damping characteristics of friction damped braced frame and its effectiveness in the mega-sub controlled structure system 被引量:19
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作者 连业达 张洵安 Sheldon Cherry 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2007年第2期171-181,共11页
Based on energy dissipation and structural control principle, a new structural configuration, called the megasub controlled structure (MSCS) with friction damped braces (FDBs), is first presented. Meanwhile, to ca... Based on energy dissipation and structural control principle, a new structural configuration, called the megasub controlled structure (MSCS) with friction damped braces (FDBs), is first presented. Meanwhile, to calculate the damping coefficient in the slipping state a new analytical method is proposed. The damping characteristics of one-storey friction damped braced frame (FDBF) are investigated, and the influence of the structural parameters on the energy dissipation and the practical engineering design are discussed. The nonlinear dynamic equations and the analytical model of the MSCS with FDBs are established. Three building structures with different structural configurations, which were designed with reference to the conventional mega-sub structures such as used in Tokyo City Hall, are comparatively investigated. The results illustrate that the structure presented in the paper has excellent dynamic properties and satisfactory control effectiveness. 展开更多
关键词 friction damped braces mega-sub controlled structure energy dissipation vibration control nonlinear dynamic system
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Hierarchical Control of Ride Height System for Electronically Controlled Air Suspension Based on Variable Structure and Fuzzy Control Theory 被引量:14
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作者 XU Xing ZHOU Kongkang +2 位作者 ZOU Nannan JIANG Hong CUI Xiaoli 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第5期945-953,共9页
The current research of air suspension mainly focuses on the characteristics and design of the air spring. In fact, electronically controlled air suspension (ECAS) has excellent performance in flexible height adjust... The current research of air suspension mainly focuses on the characteristics and design of the air spring. In fact, electronically controlled air suspension (ECAS) has excellent performance in flexible height adjustment during different driving conditions. However, the nonlinearity of the ride height adjusting system and the uneven distribution of payload affect the control accuracy of ride height and the body attitude. Firstly, the three-point measurement system of three height sensors is used to establish the mathematical model of the ride height adjusting system. The decentralized control of ride height and the centralized control of body attitude are presented to design the ride height control system for ECAS. The exact feedback linearization method is adopted for the nonlinear mathematical model of the ride height system. Secondly, according to the hierarchical control theory, the variable structure control (VSC) technique is used to design a controller that is able to adjust the ride height for the quarter-vehicle anywhere, and each quarter-vehicle height control system is independent. Meanwhile, the three-point height signals obtained by three height sensors are tracked to calculate the body pitch and roll attitude over time, and then by calculating the deviation of pitch and roll and its rates, the height control correction is reassigned based on the fuzzy algorithm. Finally, to verify the effectiveness and performance of the proposed combined control strategy, a validating test of ride height control system with and without road disturbance is carried out. Testing results show that the height adjusting time of both lifting and lowering is over 5 s, and the pitch angle and the roll angle of body attitude are less than 0.15°. This research proposes a hierarchical control method that can guarantee the attitude stability, as well as satisfy the ride height tracking system. 展开更多
关键词 electronically controlled air suspension (ECAS) ride height body attitude hierarchical control
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Parameters Sensitivity Characteristics of Highly Integrated Valve-Controlled Cylinder Force Control System 被引量:8
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作者 Kai-Xian Ba Bin Yu +4 位作者 Xiang-Dong Kong Chun-He Li Qi-Xin Zhu Hua-Long Zhao Ling-Jian Kong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第2期159-175,共17页
Nowadays, a highly integrated valve?controlled cylinder(HIVC) is applied to drive the joints of legged robots. Although the adoption of HIVC has resulted in high?performance robot control, the hydraulic force system s... Nowadays, a highly integrated valve?controlled cylinder(HIVC) is applied to drive the joints of legged robots. Although the adoption of HIVC has resulted in high?performance robot control, the hydraulic force system still has problems, such as strong nonlinearity, and time?varying parameters. This makes HIVC force control very diffcult and complex. How to improve the control performance of the HIVC force control system and find the influence rule of the system parameters on the control performance is very significant. Firstly, the mathematical model of HIVC force control system is established. Then the mathematical expression for parameter sensitivity matrix is obtained by applying matrix sensitivity analysis(PSM). Then, aimed at the sinusoidal response under(three factors and three levels) working conditions, the simulation and the experiment are conducted. While the error between the simulation and experiment can’t be avoided. Therefore, combined with the range analysis, the error in the two performance indexes of sinusoidal response under the whole working condition is analyzed. Besides, the sensitivity variation pattern for each system parameter under the whole working condition is figured out. Then the two sensitivity indexes for the three system parameters, which are supply pressure, proportional gain and initial displacement of piston, are proved experimentally. The proposed method significantly reveals the sensitivity characteristics of HIVC force control system, which can make the contribution to improve the control performance. 展开更多
关键词 Highly integrated valve?controlled cylinder system Force control system Matrix sensitivity analysis Orthogonal test design Sensitivity index
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pH-responsive mesoporous silica nanoparticles employed in controlled drug delivery systems for cancer treatment 被引量:8
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作者 Ke-Ni Yang Chun-Qiu Zhang +3 位作者 Wei Wang Paul C.Wang Jian-Ping Zhou Xing-Jie Liang 《Cancer Biology & Medicine》 SCIE CAS CSCD 2014年第1期34-43,共10页
In the fight against cancer, controlled drug delivery systems have emerged to enhance the therapeutic efficacy and safety of anti-cancer drugs. Among these systems, mesoporous silica nanoparticles (MSNs) with a func... In the fight against cancer, controlled drug delivery systems have emerged to enhance the therapeutic efficacy and safety of anti-cancer drugs. Among these systems, mesoporous silica nanoparticles (MSNs) with a functional surface possess obvious advantages and were thus rapidly developed for cancer treatment. Many stimuli-responsive materials, such as nanopartides, polymers, and inorganic materials, have been applied as caps and gatekeepers to control drug release from MSNs. This review presents an overview of the recent progress in the production of pH-responsive MSNs based on the pH gradient between normal tissues and the tumor microenvironment. Four main categories of gatekeepers can respond to acidic conditions. These categories will be described in detail. 展开更多
关键词 Mesoporous silica nanoparticles PH-RESPONSIVE controlled drug release drug delivery systems antineoplastic protocols
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Shaking table test and numerical analysis of offshore wind turbine tower systems controlled by TLCD 被引量:16
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作者 Chen Jianbing Liu Youkun Bai Xueyuan 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2015年第1期55-75,共21页
A wind turbine system equipped with a tuned liquid column damper (TLCD) is comprehensively studied via shaking table tests using a 1/13-scaled model. The effects of wind and wave actions are considered by inputting ... A wind turbine system equipped with a tuned liquid column damper (TLCD) is comprehensively studied via shaking table tests using a 1/13-scaled model. The effects of wind and wave actions are considered by inputting response- equivalent accelerations on the shaking table. The test results show that the control effect of the TLCD system is significant in reducing the responses under both wind-wave equivalent loads and ground motions, but obviously varies for different inputs, Further, a blade-hub-tower integrated numerical model for the wind turbine system is established. The model is capable of considering the rotational effect of blades by combining Kane's equation with the finite element method. The responses of the wind tower equipped with TLCD devices are numerically obtained and compared to the test results, showing that under both controlled and uncontrolled conditions with and without blades' rotation, the corresponding responses exhibit good agreement. This demonstrates that the proposed numerical model performs well in capturing the wind-wave coupled response of the offshore wind turbine systems under control. Both numerical and experimental results show that the TLCD system can significantly reduce the structural response and thus improve the safety and serviceability of the offshore wind turbine tower systems. Additional issues that require further study are discussed. 展开更多
关键词 offshore wind turbine shaking table test TLCD numerical model vibration control
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A Cretaceous Desert-Playa Sedimentary System Controlled the Potash Formation in the Simao Basin 被引量:5
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作者 WU Chihua LIU Chenglin +2 位作者 SHEN Lijian WANG Jiuyi ZHANG Hua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第3期1143-1144,共2页
Objective The Simao Basin in Yunnan Province has developed Cretaceous evaporite-bearing clastic deposits, including the Mangang and Mengyejing Formations which were originally interpreted as fluvial and lacustrine dep... Objective The Simao Basin in Yunnan Province has developed Cretaceous evaporite-bearing clastic deposits, including the Mangang and Mengyejing Formations which were originally interpreted as fluvial and lacustrine deposits. The Mangang Fm. composed of well-rounded quartz sandstones, were commonly considered as the bottom part of the Mengyejing salt series. Dttring last decades, 展开更多
关键词 A Cretaceous Desert-Playa Sedimentary system controlled the Potash Formation in the Simao Basin is for as were that of
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Miniature magnetically anchored and controlled camera system for trocar-less laparoscopy 被引量:8
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作者 ding-hui dong hao-yang zhu +5 位作者 yu luo hong-ke zhang jun-xi xiang fei xue rong-qian wu yi lv 《World Journal of Gastroenterology》 SCIE CAS 2017年第12期2168-2174,共7页
AIM To design a miniature magnetically anchored and controlled camera system to reduce the number of trocars which are required for laparoscopy.METHODS The system consists of a miniature magnetically anchored camera w... AIM To design a miniature magnetically anchored and controlled camera system to reduce the number of trocars which are required for laparoscopy.METHODS The system consists of a miniature magnetically anchored camera with a 30° downward angle, an external magnetically anchored unit, and a vision output device. The camera weighs 12 g, measures Φ10.5 mm × 55 mm and has two magnets, a vision model, a light source, and a metal hexagonal nut. To test the prototype, the camera was inserted through a 12-mm conventional trocar in an ex vivo real liver laparoscopic training system. A trocar-less laparoscopic cholecystectomy was performed 6 times using a 12-mm and a 5-mm conventional trocar. In addition, the same procedure was performed in four canine models.RESULTS Both procedures were successfully performed using only two conventional laparoscopic trocars. The cholecystectomy was completed without any major complication in 42 min(38-45 min) in vitro and in 50 min(45-53 min) using an animal model. This camera was anchored and controlled by an external unit magnetically anchored on the abdominal wall. The camera could generate excellent image. with no instrument collisions.CONCLUSION The camera system we designed provides excellent optics and can be easily maneuvered. The number of conventional trocars is reduced without adding technical difficulties. 展开更多
关键词 Trocar-less laparoscopy Magnetically anchored and controlled camera Minimally invasive surgery
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A Mathematical Model for Diffusion-Controlled Monolithic Matrix Coated with outer Membrane System 被引量:4
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作者 张国亮 石巍 +1 位作者 张凤宝 刘瑛 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第1期22-27,共6页
A release model for diffusion-controlled monolithic matrix coated with outer membrane system is proposed and solved by using the refined double integral method. The calculated results are in satisfactory agreement wit... A release model for diffusion-controlled monolithic matrix coated with outer membrane system is proposed and solved by using the refined double integral method. The calculated results are in satisfactory agreement with the experimental release data. The present model can be well used to describe the release process for all cd/cs values. In addition, the release effects of the monolithic matrix coated with outer membrane system are discussed theoretically. 展开更多
关键词 controlled release DIFFUSION mercaptopurinum monolithic matrix outer membrane
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An Experimental Study on Microcomputer Control of Pump Controlled Motor Systems
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作者 彭秀东 刘志刚 +1 位作者 金志立 胡佑德 《Journal of Beijing Institute of Technology》 EI CAS 1992年第1期59-65,共7页
Pump controlled motor electrohydraulic servo systems are much used in circumstances where high power drive is needed. This kind of system has the advantage of energy-saving. But, it also has some defects that have to ... Pump controlled motor electrohydraulic servo systems are much used in circumstances where high power drive is needed. This kind of system has the advantage of energy-saving. But, it also has some defects that have to be improved. Microcomputer control of a pump controlled motor electrohydraulic servo system is studied. A PID controller is first adopted on the closed loop control system, and experimental results are obtained. Then, a model reference adaptive controller is designed and realised on the same system applying a single board microcomputer. Experimental results show that the dynamic properties of the adaptive control system is much better than those of the PID system under different inertia load conditions. 展开更多
关键词 electrohydraulic servo systems adaptive control/pump controlled motor microcomputer control model reference
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Halloysite Nanotube Composited Thermo-responsive Hydrogel System for Controlled-release 被引量:3
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作者 林茜 巨晓洁 +3 位作者 谢锐 江明月 魏竭 褚良银 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第9期991-998,共8页
Halloysite nanotube-composited thermo-responsive hydrogel system has been successfully developed for controlled drug release by copolymerization of N-isopropylacrylamide (NIPAM) with silane-modified halloysite nanot... Halloysite nanotube-composited thermo-responsive hydrogel system has been successfully developed for controlled drug release by copolymerization of N-isopropylacrylamide (NIPAM) with silane-modified halloysite nanotubes (HNT) through thermally initiated free-radical polymerization. With methylene blue as a model drug, thermo-responsive drug release results demonstrate that the drug release from the nanotubes in the composited hy-drogel can^be well controlled by manipulating the environmental temperature. When the hydrogel network is swol- len at temperature below the lower critical solution temperature (LCST), drug releases steadily from lumens of the embedded nanotubes, whereas the drug release stops when hydrogel shrinks at temperature above the LCST. The release of model drug from the HNT-composited hydrogel matches well with its thermo-responsive volume phasetransition, and shows characteristics of well controlled release. The design strategy and release results of the pro- posed novel HNT-composited thermo-responsive hydrogel system provide valuable guidance for designing respon- s_i_ve nanocomposites for controlled-release of active agents. 展开更多
关键词 halloysite nanotube composite hydrogel controlled release thermo-responsive carder poly(N-iso-propylacrylamide)
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Controlled rocking pile foundation system with replaceable bar fuses for seismic resilience 被引量:3
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作者 Cheng Zhao Li Shuai Wang Jingquan 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2022年第3期683-696,共14页
Bridges designed following a conventional approach minimize the risk of collapse,but often require challenging,costly,and time-consuming restoration after an earthquake occurs.The new seismic design philosophy require... Bridges designed following a conventional approach minimize the risk of collapse,but often require challenging,costly,and time-consuming restoration after an earthquake occurs.The new seismic design philosophy requires bridges to maintain functionality even after severe earthquakes.In this context,this paper proposes a controlled rocking pile foundation(CRPF)system and numerically evaluates bridges′degree of seismic resilience.The CRPF system allows a pile cap to rock on a pile foundation and dissipate seismic energy through inelastic deformations of replaceable bar fuses that connect a pile cap and piles.Following the conceptual design of the CRPF system,two analytical models were developed for a bridge pier utilizing the CRPF system and a pier designed to develop a plastic hinge in its column.The analytical results indicate that,after experiencing a severe earthquake,a conventionally designed bridge pier sustained substantial damage in its column and exhibited significant residual displacement.In contrast,a pier using the CRPF system showed negligible residual displacement and maintained elastic behavior except,as expected,for bar fuses.The damaged fuses can be rapidly replaced to recover bridge seismic resistance following an earthquake.Therefore,the CRPF system helps to achieve the desired postearthquake performance objectives. 展开更多
关键词 seismic resilience bridges pier controlled rocking pile foundation repairable bar fuse
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