70 results on '"Zi-Wei Zhou"'
Search Results
52. Non-Linear Modeling and Parameter Identification of Semi-Active Engine Mounts With Air Spring
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Zi-wei Zhou and Rong Guo
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010302 applied physics ,Computer science ,business.industry ,Air spring ,General Engineering ,Stiffness ,Non linear model ,Structural engineering ,01 natural sciences ,Identification (information) ,Semi active ,0103 physical sciences ,medicine ,medicine.symptom ,business ,010301 acoustics - Abstract
Car manufacturers have been motivated to apply semi-active engine mounts to ensure superior performance in vibration attenuation during idle condition and better ability to isolate vibration which is generated by engine unbalanced force at high frequencies. This paper develops a non-linear lumped parameter model of semi-active engine mounts with air spring that focuses on the non-linearity of the rubber diaphragm and the air chamber. Then, the main rubber dynamic stiffness parameters are identified through experimental approaches with a novel-designed test rig. Other parameters including effective pumping area, main rubber spring bulge stiffness, fluid channel inertia and resistance, rubber diaphragm, and air-chamber parameters are attained through finite element analysis (FEA). Supported by the identified lumped parameters, the non-linear mathematical model could be simulated. In addition, the dynamic characteristics of the semi-active engine mount are tested through the original test rig. Therefore, comparing with the tested dynamic characteristics, the simulation result can validate the developed model and thus facilitate the structure design of the semi-active engine mount.
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- 2019
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53. A novel method based on nonparametric regression with a Gaussian kernel algorithm identifies the critical components in CHO media and feed optimization
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Liang Zhao, Wen-Song Tan, Weijian Zhang, Mao Zou, Zi-Wei Zhou, Li Fan, Haibin Wang, and Xuping Liu
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0106 biological sciences ,0301 basic medicine ,Computer science ,Bioengineering ,Feature selection ,CHO Cells ,computer.software_genre ,01 natural sciences ,Applied Microbiology and Biotechnology ,03 medical and health sciences ,symbols.namesake ,Cricetulus ,010608 biotechnology ,Partial least squares regression ,Feature (machine learning) ,Gaussian function ,Animals ,Least-Squares Analysis ,Selection (genetic algorithm) ,Nonparametric regression ,Culture Media ,Identification (information) ,Nonlinear system ,030104 developmental biology ,Research Design ,symbols ,Data mining ,computer ,Algorithms ,Biotechnology - Abstract
As the composition of animal cell culture medium becomes more complex, the identification of key variables is important for simplifying and guiding the subsequent medium optimization. However, the traditional experimental design methods are impractical and limited in their ability to explore such large feature spaces. Therefore, in this work, we developed a NRGK (nonparametric regression with Gaussian kernel) method, which aimed to identify the critical components that affect product titres during the development of cell culture media. With this nonparametric model, we successfully identified the important components that were neglected by the conventional PLS (partial least squares regression) method. The superiority of the NRGK method was further verified by ANOVA (analysis of variance). Additionally, it was proven that the selection accuracy was increased with the NRGK method because of its ability to model both the nonlinear and linear relationships between the medium components and titres. The application of this NRGK method provides new perspectives for the more precise identification of the critical components that further enable the optimization of media in a shorter timeframe.
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- 2019
54. Hydrothermal-processed volcanic ash-based geopolymers for immobilization of sodium salt wastes containing Cs
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Jing-Fei Guo, Xiaosong Jiang, Li-Ke Liu, Hongliang Sun, Xiao-Wen Sun, Song Chen, and Zi-Wei Zhou
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inorganic chemicals ,Ion exchange ,Analcime ,020209 energy ,Sodium ,chemistry.chemical_element ,02 engineering and technology ,engineering.material ,01 natural sciences ,010305 fluids & plasmas ,Geopolymer ,chemistry.chemical_compound ,Adsorption ,Nuclear Energy and Engineering ,chemistry ,Pollucite ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,engineering ,Sodalite ,Leaching (metallurgy) ,Nuclear chemistry - Abstract
Volcanic ash-based sodium salts-containing geopolymer with target composition close to that of Pollucite Cs(AlSi2O6) was formulated at 200 °C by mild hydrothermal method to immobilize Cs as waste material. The impact of three salts, namely, Na2SO4, NaCl, and NaNO2 on mineral phases of geopolymer waste forms and immobilization of Cs+ was investigated, specifically, regarding salts/NaOH molar ratio. Results indicate that when salts/NaOH molar ratio was 1:9, major mineral phase of geopolymer waste was analcime, whereas major mineral phase of matrix samples with salts/NaOH molar ratio as 1:1 was sodalite, which is beneficial to accommodate amounts of anions. Pollucite was formed in all samples with the introduction of CsOH·H2O to matrix samples. Product Consistency Test (PCT) leaching results indicate that NaOH plays key role in immobilization of Cs+. Moreover, C–S–H gel exhibits functional adsorption on Cs+; therefore, it has positive effect on the immobilization of Cs+. In Cs-containing samples with high salts/NaOH molar ratio, PCT leaching results show that high salts/NaOH molar ratio leads to low leaching concentrations of salts. However, only partial amounts of NO2− can be immobilized by sodalite due to oxidation of NO2− to NO3−. Furthermore, the attachment of SO42− to the surface of C–S–H gel can prevent the destruction of structure of C–S–H gel by ion exchange of Al3+ and Si4+. As a result, SO42−-containing samples have the lowest Cs+ leaching concentration among all Cs-containing samples with high salts/NaOH molar ratios. The immobilization of Cs+ can be further improved by the adsorption of C–S–H gel on Cs+. Results suggest that besides the formation of Pollucite, the immobilization of Cs+ also depends on various salts in sodium salts wastes containing Cs.
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- 2021
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55. Validation of reference genes for gene expression studies in post-harvest leaves of tea plant (Camellia sinensis)
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Zi-wei Zhou, Yun Sun, Ting-ting Deng, Zhongxiong Lai, Hui-li Deng, Qing-yang Wu, Chuan Yue, and Bin-bin Liu
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0106 biological sciences ,lcsh:Medicine ,Plant Science ,Biology ,01 natural sciences ,Camellia sinensis ,General Biochemistry, Genetics and Molecular Biology ,CsLOX1 ,03 medical and health sciences ,Transcription (biology) ,Reference genes ,Gene expression ,Post-harvest leaves ,Agricultural Science ,Molecular Biology ,Gene ,030304 developmental biology ,0303 health sciences ,Manufacturing process ,business.industry ,General Neuroscience ,RT-qPCR ,lcsh:R ,Plant physiology ,food and beverages ,General Medicine ,Biotechnology ,Reverse transcription polymerase chain reaction ,General Agricultural and Biological Sciences ,business ,010606 plant biology & botany - Abstract
Tea is one of three major non-alcoholic beverages that are popular all around the world. The economic value of tea product largely depends on the post-harvest physiology of tea leaves. The utilization of quantitative reverse transcription polymerase chain reaction is a widely accepted and precise approach to determine the target gene expression of tea plants, and the reliability of results hinges on the selection of suitable reference genes. A few reliable reference genes have been documented using various treatments and different tissues of tea plants, but none has been done on post-harvest leaves during the tea manufacturing process. The present study selected and analyzed 15 candidate reference genes: Cs18SrRNA, CsGADPH, CsACT, CsEF-1α, CsUbi, CsTUA, Cs26SrRNA, CsRuBP, CsCYP, CselF-4α, CsMON1, CsPCS1, CsSAND, CsPPA2, CsTBP. This study made an assessment on the expression stability under two kinds of post-harvest treatment, turn over and withering, using three algorithms—GeNorm, Normfinder, and Bestkeeper. The results indicated that the three commonly used reference genes, CsTUA, Cs18SrRNA, CsRuBP, together with Cs26SrRNA, were the most unstable genes in both the turn over and withering treatments. CsACT, CsEF-1α, CsPPA2, and CsTBP were the top four reference genes in the turn over treatment, while CsTBP, CsPCS1, CsPPA2, CselF-4α, and CsACT were the five best reference genes in the withering group. The expression level of lipoxygenase genes, which were involved in a number of diverse aspects of plant physiology, including wounding, was evaluated to validate the findings. To conclude, we found a basis for the selection of reference genes for accurate transcription normalization in post-harvest leaves of tea plants.
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- 2018
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56. Research and Application of Key Technologies for EHV Intelligent Series Compensation Control and Protection System
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Zheng, Li, primary, Xiao-Wei, Fan, additional, Zhen-Dong, Li, additional, Hai-Qing, An, additional, Yi-Chen, Liu, additional, Jie, Liu, additional, and Zi-Wei, Zhou, additional
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- 2019
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57. VEGI attenuates the inflammatory injury and disruption of blood–brain barrier partly by suppressing the TLR4/NF-κB signaling pathway in experimental traumatic brain injury
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Yuan Zhou, Jianning Zhang, Tingting Hu, Rongcai Jiang, Zi-wei Zhou, Zilong Zhao, Gongjie Yu, and Weiwei Gao
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Male ,Vascular Endothelial Growth Factor A ,Traumatic brain injury ,Angiogenesis ,Brain damage ,Blood–brain barrier ,Vascular endothelial growth inhibitor ,Neuroprotection ,Proinflammatory cytokine ,medicine ,Animals ,Molecular Biology ,Microglia ,business.industry ,General Neuroscience ,NF-kappa B ,Brain ,medicine.disease ,Mice, Inbred C57BL ,Toll-Like Receptor 4 ,Disease Models, Animal ,Neuroprotective Agents ,Treatment Outcome ,medicine.anatomical_structure ,Blood-Brain Barrier ,Astrocytes ,Brain Injuries ,Immunology ,Cancer research ,Cytokines ,Neurology (clinical) ,medicine.symptom ,business ,Signal Transduction ,Developmental Biology - Abstract
Acute traumatic brain injury (TBI) tends to cause the over-activation of inflammatory response and disruption of blood brain barrier (BBB), associating with long-term cognitive and behavioral dysfunction. Vascular endothelial growth inhibitor (VEGI), as a suppressor in the angiogenesis specifically by inducing apoptosis in proliferating endothelial cells, has been applied to different diseases, especially the tumors. But rare study had been done in the field of brain injury. So in this study, we investigated the effects and mechanisms associated with VEGI-induced neuroprotection following CNS injury in mice TBI models. We demonstrated that the VEGI treatment reduced the contusion brain tissue loss, the permeation of inflammatory cells (MPO(+)) and the activation of microglia (Iba-1(+)). The treatment up-regulated the tight junction proteins (CLN5, ZO-1 and OCLN), which are vital importance for the integrity of the blood brain barrier (BBB), the B-cell lymphoma 2 (Bcl-2) cell survival factors, while down-regulated the expression of TLR4, NF-κB and inflammatory cytokines (IL-1β, TNF-α, iNOS). The treatment also decreased the expression of reactive astrocytes (GFAP(+)), as well as the VEGF, and lowered the permeability of Evens Blue (EB). These findings suggested that the VEGI-treatment could alleviate the post-traumatic excessive inflammatory response, and maintain the stability of blood vessels, remitting the secondary brain damage.
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- 2015
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58. Epidemiological parameters of COVID-19 and its implication for infectivity among patients in China, 1 January to 11 February 2020.
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Qing-Bin Lu, Yong Zhang, Ming-Jin Liu, Hai-Yang Zhang, Neda Jalali, An-Ran Zhang, Jia-Chen Li, Han Zhao, Qian Song, Tian-Shuo Zhao, Jing Zhao, Han-Yu Liu, Juan Du, Ai-Ying Teng, Zi-Wei Zhou, Shi-Xia Zhou, Tian-Le Che, Tao Wang, Tong Yang, and Xiu-Gang Guan
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- 2020
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59. A Self-organizing Cooperative Hunting by Swarm Robotic Systems Based on Loose-preference Rule
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Wang-Bao Xu, Zhi-Yong Ren, Zi-Wei Zhou, Tian-Yun Huang, and Xuebo Chen
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Lyapunov stability ,Engineering ,business.industry ,Process (engineering) ,Materials Science (miscellaneous) ,Stability (learning theory) ,Swarm behaviour ,Motion controller ,General Business, Management and Accounting ,Industrial and Manufacturing Engineering ,Computer Science::Robotics ,Decomposition (computer science) ,Artificial intelligence ,Motion planning ,Business and International Management ,Cooperative hunting ,General Agricultural and Biological Sciences ,business - Abstract
A novel self-organizing approach to cooperative hunting by swarm robotic systems is put forward. Firstly, an individual autonomous motion planning is presented, and the cooperative hunting behaviors are mathematically described. According to decomposition of hunting behaviors, the loose-preference rule is established for the individuals to form the ideal hunting formation during the self-organizing process by the interaction between the target and individuals. Then, we employ the proposed rule to design the autonomous motion controller of the individuals. Finally, the stability of self-organizing system is analyzed by Lyapunov stability criteria. Simulations and experiments demonstrate the feasibility and effectiveness of the proposed approach to cooperative hunting by swarm robotic systems.
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- 2013
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60. A Improved Stereo Matching Fast Algorithm Based on Dynamic Programming
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Ge Li, Chang Le Li, Ji Zhuang Fan, and Zi Wei Zhou
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Matching (statistics) ,Image quality ,business.industry ,Computer science ,Mechanical Engineering ,Template matching ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Scan line ,Dynamic programming ,Line segment ,Mechanics of Materials ,Feature (computer vision) ,General Materials Science ,Computer vision ,Artificial intelligence ,business ,Local algorithm - Abstract
Compared with the local algorithm in stereo matching, the high quality disparity space image is calculated by the global algorithm, which is difficult to use in practical application for its long computation time. The dynamic programming is one of the global algorithms with a fast matching speed, but it has strip blemish in matching result. In this paper, a new dynamic programming based method is proposed to accelerate the matching speed and improve the matching quality. Firstly, the color feature of two images are calculated using the Laplacians of Gaussian pyramid algorithm, and the color feature of the image pair obtained are matched. Secondly, the matching points are taken as the ground control points of the scan line, which is cut into several short line segments. Finally, all line segments are matched to obtain the disparity of the scan line. The experimental results show that the matching speed is accelerated greatly with improved disparity image quality
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- 2012
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61. A New Algorithm of Path Planning Based on Local Data
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Zi Wei Zhou, Nai Dong Cui, Xin Yu O Yang, and Wang Bao Xu
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business.industry ,Computer science ,Mechanical Engineering ,Motion controller ,Any-angle path planning ,Mobile robot navigation ,Data mapping ,Mechanics of Materials ,Obstacle ,Path (graph theory) ,Robot ,General Materials Science ,Computer vision ,Artificial intelligence ,Motion planning ,business ,Algorithm - Abstract
A novel new algorithm of path planning is proposed for the robot path planning based on the local data map in the robot autonomous navigation. The algorithm is used to search for the local optimal path from the current position of the robot to the target according to the known sensor data. If the robot cannot reach the target directly, the temporary target point which the robot can reach will be set up according to the optimal path. The algorithm is effective under the complicated unknown environment and moving obstacle situation which fast searching speed, it can be adapted into the practical applications and the multi-robot harmony easily. The simulation result shows that this method can provide a better planning path by comparing with the traditional planning algorithms such as artificial potential field and wall-following
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- 2012
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62. Active Compliance Control for the Leg of Hexapod Robot HITCR-II
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He Zhang, Zi Wei Zhou, Jie Zhao, and Yu Bin Liu
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Engineering ,Hexapod ,business.industry ,Stiffness ,Terrain ,Robotics ,General Medicine ,Robot control ,Control theory ,Redundancy (engineering) ,medicine ,Torque ,Robot ,Artificial intelligence ,medicine.symptom ,business ,Simulation ,ComputingMethodologies_COMPUTERGRAPHICS - Abstract
Walking is an effective way of locomotion for the robot system; especially for the Hexapod robots, walking offers a better robustness for its redundancy of limbs. In order to enhance the adaptability of walking on unstructured terrain, a hexapod robot leg structure with the sensing ability has been developed. This structure is equipped with the 3-D force sensor at the tibia and the torque sensors at the first and second joint. The compliance control has been adopted to control the force of the foot end, and by combining with the real-time parameter estimation algorithm, the shape and stiffness can be updated to make the robot adapt to the mutative terrain better. Thus, the self-adaptively active compliance control for the hexapod robot leg has been realized, and the effectiveness of the controller has been verified through virtual simulation.
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- 2012
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63. Application of Phase-Sensitivity Detector in Air-Coupled Ultrasonic Testing
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Zi Wei Zhou, Wei Dong, and Zheng Gan Zhou
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Signal processing ,Materials science ,Acoustics ,Superheterodyne receiver ,Ultrasonic testing ,Detector ,Phase (waves) ,General Medicine ,Signal ,law.invention ,Signal-to-noise ratio ,law ,Electronic engineering ,Sensitivity (electronics) - Abstract
The signal to noise ration of air-coupled ultrasonic testing is very poor and there is long time pulse residue, so it need adopt appropriate signal processing method to enhancing the SNR of received signal. Factors, which affect the received signal in ultrasonic testing process, is analyzed, phase sensitivity detection technology is presented to process the received signal, and ultrasonic testing information can be acquired by the calculation of phase signal. The principle of super-heterodyne receiver and phase sensitivity detector is introduced; some problem which should be pay attention in ultrasonic testing process is explained. Based on the research result, air-coupled ultrasonic testing system with phase sensitivity detector is constituted. Experiment results of image testing on carbon fiber reinforced plastic plate indicated that, phase sensitivity detection technology can improved signal to noise ratio of system and testing effect in evidence.
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- 2012
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64. [One Case of Multiple Myeloma with Central Never System Infiltration]
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Xiao-Jun, Liu, Fu-Xu, Wang, Lin, Yang, Ying, Wang, Shu-Peng, Wen, Jian-Min, Luo, Zi-Wei, Zhou, and Xue-Jun, ZhANG
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Central Nervous System ,Plasma Cells ,Humans ,Multiple Myeloma - Abstract
To analyses and summarize a case of multiple myeloma with disseminated infiltration in central nervous system.The results of laboratorial examination and clinical data were analyzed and compared in the light of published literatures.The headache and diplopia were caused by infiltration of multiple myeloma cells to the central nervous system. Unlike those reported in the literatures, this case was a rare case of disseminated infiltration inside the brain, and plasma cells were CD56+, this patient has not yet accepted any multiple myeloma-associated treatment as like that reported in the literatures. And different from cases reported, this patient showed a good response to the intrathecal chemotherapy.Whether this good response is due to a heterogeneity of MM or effect of treatment-associated drug is still to be decided.
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- 2015
65. Electrical stimulation improved cognitive deficits associated with traumatic brain injury in rats
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Weiwei Gao, Shuyuan Yue, Yuan Zhou, Zi-wei Zhou, Jianning Zhang, Zhi-tong Zheng, Rongcai Jiang, Ya-dan Li, and Xin-long Dong
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Male ,0301 basic medicine ,medicine.medical_specialty ,Traumatic brain injury ,Angiogenesis ,Morris water navigation task ,Stimulation ,Hippocampus ,Endothelial progenitor cell ,cognitive deficit ,Rats, Sprague-Dawley ,angiogenesis ,03 medical and health sciences ,Behavioral Neuroscience ,endothelial progenitor cell ,Cognition ,0302 clinical medicine ,Von Willebrand factor ,Internal medicine ,Brain Injuries, Traumatic ,von Willebrand Factor ,medicine ,Animals ,Hippocampus (mythology) ,Cognitive Dysfunction ,electrical stimulation ,Maze Learning ,Cognitive deficit ,Original Research ,Endothelial Progenitor Cells ,biology ,traumatic brain injury ,medicine.disease ,Electric Stimulation ,Rats ,Surgery ,Treatment Outcome ,030104 developmental biology ,Endocrinology ,biology.protein ,medicine.symptom ,Psychology ,030217 neurology & neurosurgery - Abstract
Introduction Cognitive deficits associated with traumatic brain injury (TBI) reduce patient quality of life. However, to date, there have been no effective treatments for TBI-associated cognitive deficits. In this study, we aimed to determine whether electrical stimulation (ES) improves cognitive deficits in TBI rats. Methods Rats were randomly divided into three groups: the Sham control group, electrical stimulation group (ES group), and No electrical stimulation control group (N-ES group). Following fluid percussion injury, the rats in the ES group received ES treatment for 3 weeks. Potent cognitive function-relevant factors, including the escape latency, time percentage in the goal quadrant, and numbers of CD34+ cells, von Willebrand Factor+ (vWF+) vessels, and circulating endothelial progenitor cells (EPCs), were subsequently assessed using the Morris water maze (MWM) test, immunohistochemical staining, and flow cytometry. Results Compared with the rats in the N-ES group, the rats in the ES group exhibited a shorter escape latency on day 3 (p = .025), day 4 (p = .011), and day 5 (p = .003), as well as a higher time percentage in the goal quadrant (p = .025) in the MWM test. After 3 weeks of ES, there were increased numbers of CD34+ cells (p = .008) and vWF+ vessels (p = .000) in the hippocampus of injured brain tissue in the ES group compared with those in the N-ES group. Moreover, ES also significantly increased the number of EPCs in the peripheral blood from days 3 to 21 after TBI in the ES group (p
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- 2017
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66. Erythropoietin regulates immune/inflammatory reaction and improves neurological function outcomes in traumatic brain injury
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Tong-heng Chen, Weiwei Gao, Jie-li Chen, Zi-wei Zhou, Jianning Zhang, Ya-dan Li, Fei Li, and Zhi-tong Zheng
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Male ,neuroimmune ,0301 basic medicine ,Traumatic brain injury ,medicine.medical_treatment ,Interleukin-1beta ,Brain Edema ,Inflammation ,neuroinflammation ,Proinflammatory cytokine ,Mice ,03 medical and health sciences ,Behavioral Neuroscience ,Cognition ,0302 clinical medicine ,Immune system ,Brain Injuries, Traumatic ,medicine ,Animals ,Neuroinflammation ,Original Research ,Tumor Necrosis Factor-alpha ,business.industry ,regulatory T cell (Treg) ,traumatic brain injury ,Brain ,medicine.disease ,Disease Models, Animal ,Neuroprotective Agents ,Treatment Outcome ,030104 developmental biology ,Cytokine ,Erythropoietin ,Immunology ,Tumor necrosis factor alpha ,erythropoietin ,medicine.symptom ,business ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Introduction Traumatic brain injury (TBI) remains a leading cause of disability and death among young people in China. Unfortunately, no specific pharmacological agents to block the progression of secondary brain injury have been approved for clinical treatment. Recently, neuroprotective effects of erythropoietin (EPO) have been demonstrated in addition to its principal function in erythropoiesis, and hence it is viewed as a potential drug for TBI. In this study, we have investigated the neuroprotective effects of EPO associated with immune/inflammatory modulation in a mouse experimental TBI model. Methods EPO (5000 U/kg body weight, i.p.) was injected at 1 hr, 1, 2, and 3 days after TBI, and its effect on cognitive function, brain edema, immune/inflammatory cells including regulatory T cells (Tregs), neutrophils, CD3+ T cells, and microglia, cytokines including interleukin-10 (IL-10), transforming growth factor-β (TGF-β), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) were evaluated at different time points after treatment. Results EPO treatment significantly decreased brain edema and improved cognitive function when compared to Saline-treated mice (p
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- 2017
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67. The apposite way path planning algorithm based on local message
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Wang-bao Xu, He Zhang, Jie Zhao, Zi-wei Zhou, Changle Li, and Ge Li
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Engineering ,Social robot ,business.industry ,Mobile robot ,Control engineering ,Mobile robot navigation ,Robot control ,Computer Science::Robotics ,Obstacle ,Obstacle avoidance ,Robot ,Motion planning ,business ,Algorithm - Abstract
According to the problems of autonomous robotic navigation in complex environments, an opposite way path planning algorithm and a novel robot controller based on inertial property is proposed. Firstly, the opposite way path planning algorithm getting the local obstacle message through robot, according to the known obstacles a optimal path calculated which can carries the robot to get to the ultimate target. Secondly, a robot controller based on attractive force function and repulsive force function is designed. The controller can keep the robot away from the obstacle, and escape from the local minima when the robot is blocked by obstacle. The simulation results show that this method has a better optimization result than other common methods such as bug and artificial potential field.
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- 2012
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68. A new stereo matching algorithm based on image segmentation
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Ge Li, Xin Yu Oyang, Jizhuang Fan, Jie Zhao, and Zi-wei Zhou
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Segmentation-based object categorization ,business.industry ,Image quality ,Template matching ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Pattern recognition ,Image segmentation ,Image texture ,Computer Science::Computer Vision and Pattern Recognition ,Cut ,Computer vision ,Artificial intelligence ,Graph cuts in computer vision ,business ,Algorithm ,Local algorithm ,Mathematics - Abstract
Comparing with the local algorithm in stereo matching, the global algorithm can get highly quality disparity space image (DSI) usually. The graph cuts algorithm, as the traditional global matching method, can get the highly quality DSI with long computation time, so the graph cuts algorithm is difficult to used in real-time matching applications. In this paper, a new method is proposed to accelerate the matching speed. Firstly, the segments of the image are calculated using the Gaussians pyramid (DoGs) computing method, secondly calculate the disparity range of two corresponding image segments in image pair using the color feature, and every segment pair is matched based on graph cuts algorithm according to the offset of disparity range in parallel time, finally all the segments are assembled into a whole disparity image. The experimental results show that the matching speed is accelerated greatly with a high disparity image quality.
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- 2012
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69. Evolution of quality assurance in higher education from INQAAHE GGP to ISGs − Are quality assurance agencies in Asia ready to the emerging modules?
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Angela Yung Chi Hou, Christopher Hong-Yi Tao, Kyle Zi-Wei Zhou, Arianna Fang Yu Lin, Edward Hung Cheng Su, and Ying Chen
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Quality assurance ,INQAAHE ,Higher education ,Qualification recognition ,Education - Abstract
Purpose – In 2022, the International Network for Quality Assurance (QA) Agencies in Higher Education (INQAAHE) published the new guidelines by adding three QA modules in response to the changing higher education landscape. The paper aims to investigate the transformative focus of quality assurance in higher education globally as well as Asian response to three new QA modules according to the INQAAHE ISGs. Design/methodology/approach – The research conducted a quantitative approach for data collection. An on-line survey was conducted to perceive QA practices, perceptions toward new emerging QA modules and challenges encountered. In total, there were 26 responses from 18 territories with 22 QA agencies. A total of 13 out of them have a national qualifications framework in place. Findings – Three are three major findings in the study. First, national policy and criteria and standards in distance education have been developed in the majority of Asian nations. Second, non-signatories of the Tokyo Convention had a higher proportion of having related policies, regulations and criteria in CBHE and distance education. Third, national policies and regulations; and lack of professional staff are two common challenges implementing QA in new types of providers. Originality/value – The findings are of value for policymakers, QA agencies and universities to advocate the new QA model as a systematic approach in response to changing higher education landscape in the post pandemic era.
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- 2024
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70. Small Object Detection Based on Deep Convolutional Neural Networks:A Review
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DU Zi-wei, ZHOU Heng, LI Cheng-yang, LI Zhong-bo, XIE Yong-qiang, DONG Yu-chen, QI Jin
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deep learning ,small object detection ,multi-scale feature fusion ,anchor-free ,attention mechanism ,Computer software ,QA76.75-76.765 ,Technology (General) ,T1-995 - Abstract
Small object detection has long been one of the most challenging problems in computer vision.Since small objects have the characteristics of small coverage area,low resolution,and lack of feature information,their detection effect is not ideal compared to large-sized objects.In recent years,the small object detection algorithm based on deep convolutional neural networks has developed vigorously,and been successfully used in fields such as satellite remote sensing and driverless vehicles.This survey makes a taxnomy,analysis and comparison of existing algorithms.First,the difficulties of small object detection and common detection datasets are introduced.Second,the existing detection algorithms are systematically described from five aspects:backbone network,pyramid structure,anchor design,optimization of object and a bag of species,to provide ideas for further improving the performance of small object detection algorithms.Then,we briefly summarize the existing small object detection algorithms and analyze their performance of the listed algorithm on common dataset.Finally,the application and the future research direction in the field of small object detection has been prospected.
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- 2022
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