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Development of an Intelligent Vehicle Experiment System

Chinese Journal of Mechanical Engineering 2010年第6期23卷 684-689页

作者： YANG Xinhong gao feng liu Guoliang WANG Guofu XU Guoyan School of Transportation Science ＆ Engineering Beihang University Beijing 100191 China

Existing vehicle experiment systems tend to focus on the research of vehicle dynamics by conducting performance tests on every system or some parts of the vehicle so as to improve the entire performance of the vehicle. Virtual technology is widely utilized in various vehicle test-beds. These test-beds are mainly used to simulate the driving training, conduct the research on drivers＇ behaviors, or give virtual demonstrations of the transportation environment. However, the study on the active safety of the running vehicle in the virtual environment is still insufficient. A virtual scene including roads and vehicles is developed by using the software Creator and Vega, and radars and cameras are also simulated in the scene. Based on dSPACE＇s rapid prototyping simulation and its single board DS1103, a simulation model including vehicle control signals is set up in MATLAB/Simulink, the model is then built into C code, and the system defined file（SDF） is downloaded to the DS1103 board through the experiment debug software ControlDesk and is kept running. Programming is made by mixing Visual C＋＋ 6.0, MATLAB API and Vega API. Control signals are read out by invoking library function MLIB/MTRACE of dSPACE. All the input, output, and system state values are acquired by arithmetic and are dynamically associated with the running status of the virtual vehicle. An intelligent vehicle experiment system is thus developed by virtue of program and integration. The system has not only the demonstration function, such as general driving, cruise control, active avoiding collision, but also the function of virtual experiment. Parameters of the system can be set according to needs, and the virtual test results can be analyzed and studied and used for the comparison with the existing models. The system reflects the running of the intelligent vehicle in the virtual traffic environment, at the same time, the system is a new attempt performed on the intelligent vehicle travel research and prov

关键词： intelligent vehicle signals integration mix programming virtual experiments

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Near-bed sediment transport in a heavily modified coastal plain estuary

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International Journal of Sediment Research 2014年第2期29卷 232-245页

作者： gao-feng liu Jia-xue WU Yuan-ye WANG Shanghai Estuarine and Coastal Science Research Center The Center for Coastal Ocean Science and Technology Research School of Marine SciencesSun Yat-sen University

Numerous estuaries of the world have been strongly modified by human *** interferences can make great adjustments of not only sediment transport processes,but also the collective behavior of the *** paper provides a typical case of a heavily modified coastal plain estuary of Sheyang on the China coast,where a sluice barrage was built in 1956 to stop the intrusions of storm surges and saline *** sets of instrumented tripods were simultaneously deployed along a cross-shore transect to continuously observe near-bed flow currents and sediment *** in-situ surveys lasted over a spring and neap tide cycle when a strong wind event occurred in the neap *** of flows and sediment transport between tide-dominated and wind-dominated conditions demonstrated the important role of episodic wind events in flows and sediment *** wind-induced currents,bottom stresses,and sediment transport rates were significantly greater when wind was present than corresponding quantities induced by the *** long-shore sediment transport induced by winds exceeds the cross-shore component,especially near the river mouth *** results indicate the noticeable importance of wave-dominated coastal processes in shaping topographic features.A regime shift of estuarine evolution under highly intense human forcing occurs from fluvial to marine *** finding suggests that the management strategy of the estuarine system should focus on the restoration of estuarine processes,rather than the present focus on inhibition of marine dynamics.

关键词： Estuarine dynamics Sediment transport Strong wind event Anthropogenic effects

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Deformation behavior and microstructural evolution during hot compression of an a+b Ti-6.5Al-3.5Mo-1.5Zr-0.3Si alloy

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International Journal of Minerals,Metallurgy and Materials 2011年第3期18卷 344-351页

作者： gao-feng liu Shang-zhou Zhang Li-qing Chen Jian-xun Qiu School of Environmental and Materials Engineering Yantai University Yantai 264005 China State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 China

The effect of processing parameters on the flow response and microstructural evolution of the a＋b titanium alloy Ti-6.5Al-3.5Mo-1.5Zr-0.3Si has been studied by conducting isothermal hot compressive tests at a strain rate of 0.01-10 s-1 at 860-1100°C. The true stress-true strain curves of the sample hot-compressed in the a＋b phase region exhibit a peak stress followed by continuous flow softening, whereas in the b region, the flow stress attains a steady-state regime. At a strain rate of 10 s-1, the alloy exhibits plastic flow insta-bilities. According to the kinetic rate equation, the apparent activation energies are estimated to be about 674-705 kJ/mol in the a＋b region and 308-335 kJ/mol in the b region, respectively. When deformed in the a＋b region, the globularization process of the a colony structure occurs, and a dynamic recrystallized microstructures are observed to show bimodal. Dynamic recrystallization can take place in the b region irrespective of starting deformed structures.

关键词： titanium alloys hot pressing deformation microstructural evolution activation energy

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Effect of recombinant human endostatin onradiotherapy for esophagus cancer

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Asian Pacific Journal of Tropical Medicine 2016年第1期9卷 84-88页

作者： gao-feng liu Hui Chang Bao-Tian Li Yong Zhang Dan-Dan Li Yan liu Yang Yang Department of Thoracic Surgery No.153 Hospital of Liberation Army Department of Cardiothoracic Surgery Xiangya Hospital Central-South University

Objective:To investigate the effect of radiotherapy plus recombinant human endostatin（RHendostatin） on esophageal cancer and its ***:A total of SO nudemice were equally randomized into control group,radiotherapy group,and combined therapy group Ⅰ,Ⅱ,and Ⅲ after inoculating with Ecal09 cell suspension（1×107 cells/mL）.On the day of grouping,control group and radiotherapy group were injected normal saline,while radiotherapy group and 3 combined therapy groups received radiotherapy;besides,combined therapy group Ⅰ,Ⅱ,and Ⅲ was injected RH-endostatin of 2.5,5,10 mg/kg *** 3-week therapy,the tumors of each group were collected and microvessel density and VEGF expression in tumors were *** vitro,Eca109 cells were divided into control group,radiotherapy group,and combined therapy ***-eight hours after treatment cell cycle distribution and apoptosis rate were detected,and the activity of VEGF signal paths was semiquantitatively ***:Since the 6th day of treatment,the relative tumor proliferation rate of combined therapy group Ⅱ was lower than radiotherapy group（P<0.05） and 40%since the 15 th *** microvessel density and EGFR expression in combined therapy group Ⅱ were lower than radiotherapy group（P<0.05）.In vitro,the cell percentage in S and G2/M phase of combined therapy group cells was lower than that in radiotherapy group cells,while the apoptosis rate and the expression of VEGF,AKT,p-AKT,ERK1/2 and p-ERKl/2 in combined group were higher than that in radiotherapy group（P<0.05）.Conclusions:RH-endostatin promotes the efficacy of radiotherapy on esophageal cancer,which may be partly realized by inhibiting the activity of VEGF related signal paths.

关键词： Esophageal cancer Nudemice Vascular endothelial growth factor Radiotherapy Recombinant human endostatin

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A chromosome-level reference genome of nonheading Chinese cabbage[Brassica campestris(*** rapa)***]

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Horticulture Research 2020年第1期7卷 1-13页

作者： Ying Li gao-feng liu Li-Ming Ma Tong-Kun liu Chang-Wei Zhang Dong Xiao Hong-Kun Zheng Fei Chen Xi-Lin Hou State Key Laboratory of Crop Genetics&Germplasm Enhancement Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(East China)Ministry of Agriculture and Rural Affairs of the P.R.ChinaEngineering Research Center of Germplasm Enhancement and Utilization of Horticultural CropMinistry of Education of the P.R.ChinaCollege of HorticultureNanjing Agricultural UniversityNanjing 210095China Biomarker Technologies Corporation Beijing 101300China

Non-heading Chinese cabbage(NHCC)is an important leafy vegetable cultivated ***,we report the first high-quality,chromosome-level genome of NHCC001 based on PacBio,Hi-C,and Illumina sequencing *** assembled NHCC001 genome is 405.33 Mb in size with a contig N50 of 2.83 Mb and a scaffold N50 of 38.13 *** 53%of the assembled genome is composed of repetitive sequences,among which long terminal repeats(LTRs,20.42%of the genome)are the most *** Hi-C data,97.9%(396.83 Mb)of the sequences were assigned to 10 *** assessment showed that this *** NHCC001 genome assembly is of better quality than other currently available *** assemblies and that it contains 48,158 protein-coding genes,99.56%of which are annotated in at least one functional *** genomic analysis confirmed that *** NHCC001 underwent a whole-genome triplication(WGT)event shared with other Brassica species that occurred after the WGD events shared with *** related to ascorbic acid metabolism showed little variation among the three *** *** numbers of genes involved in glucosinolate biosynthesis and catabolism were higher in NHCC001 than in Chiifu and Z1,due primarily to tandem *** newly assembled genome will provide an important resource for research on ***,especially *** ***.

关键词： heading fir cultivated

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Neural progenitor cells derived from fibroblasts induced by small molecule compounds under hypoxia for treatment of Parkinson’s disease in rats

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Neural Regeneration Research 2023年第5期18卷 1090-1098页

作者： Yu Guo Yuan-Yuan Wang Ting-Ting Sun Jia-Jia Xu Pan Yang Cai-Yun Ma Wei-Jun Guan Chun-Jing Wang gao-feng liu Chang-Qing liu School of Laboratory Medicine School of Life SciencesBengbu Medical CollegeBengbuAnhui ProvinceChina National Germplasm Resource Center for Domestic Animals Institute of Animal ScienceChinese Academy of Agricultural ScienceBeijingChina Department of Neuroscience University of Connecticut Health CenterFarmingtonCTUSA

Neural progenitor cells(NPCs) capable of self-renewal and differentiation into neural cell lineages offer broad prospects for cell therapy for neurodegenerative diseases. However, cell therapy based on NPC transplantation is limited by the inability to acquire sufficient quantities of NPCs. Previous studies have found that a chemical cocktail of valproic acid, CHIR99021, and Repsox(VCR) promotes mouse fibroblasts to differentiate into NPCs under hypoxic conditions. Therefore, we used VCR(0.5 mM valproic acid, 3 μM CHIR99021, and 1 μM Repsox) to induce the reprogramming of rat embryonic fibroblasts into NPCs under a hypoxic condition(5%). These NPCs exhibited typical neurosphere-like structures that can express NPC markers, such as Nestin, SRY-box transcription factor 2, and paired box 6(Pax6), and could also differentiate into multiple types of functional neurons and astrocytes in vitro. They had similar gene expression profiles to those of rat brain-derived neural stem cells. Subsequently, the chemically-induced NPCs(ciNPCs) were stereotactically transplanted into the substantia nigra of 6-hydroxydopamine-lesioned parkinsonian rats. We found that the ciNPCs exhibited long-term survival, migrated long distances, and differentiated into multiple types of functional neurons and glial cells in vivo. Moreover, the parkinsonian behavioral defects of the parkinsonian model rats grafted with ciNPCs showed remarkable functional recovery. These findings suggest that rat fibroblasts can be directly transformed into NPCs using a chemical cocktail of VCR without introducing exogenous factors, which may be an attractive donor material for transplantation therapy for Parkinson’s disease.

关键词： cell reprogramming cell transplantation hypoxia neural progenitor cells neurological function Parkinson’s disease small molecule compounds substantia nigra

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Inhibition of Nogo expression to promote repair after spinal cord injury

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Chinese Medical Journal 2012年第22期125卷 4044-4048页

作者： SUN Hong-hui gao feng liu Bin YU Hai-tao KONG Ning liu Guo-min Jilin Univ Hosp 2 Dept Orthoped Changchun 130041 Jinlin Peoples R China Jilin Univ Hosp 2 Dept Gen Surg Changchun 130041 Jinlin Peoples R China Jilin Univ Coll Pharm Dept Regenerat Med Changchun 130041 Jinlin Peoples R China

Background One of the reasons for poor neuroregeneration after central nervous system injury is the presence of inhibitory factors such as Nogo. Here, we tested the inhibition of Nogo by RNA interference both in vitro and in vivo, using recombinant adenovirus-mediated transfection of short hairpin RNAs, to explore a new method of treatment for spinal cord injury. Methods We designed and cloned two Nogo-specific short hairpin RNAs and an unrelated short hairpin RNA, packaged the clones into adenovirus, and amplified the recombinant virus in 293 cells. We then tested the inhibition of Nogo expression both in vitro in adenovirus-transfected oligodendrocytes and in vivo in spinal cord tissue from adenovirus-transfected spinal cord injury model rats. We tested Nogo expression at the mRNA level by reverse-transcription PCR and at the protein level by Western blotting and immunohistochemistry. Results In vitro, the two specific Nogo short hairpin RNAs decreased Nogo mRNA expression by 51% and 49%, respectively, compared with Nogo expression in cells transfected with the unrelated control small hairpin RNA （P 〈0.005）. Similarly, Nogo protein expression decreased by 50% and 48%, respectively （P 〈0.005）. In vivo, in spinal cord injury model rats, the two specific Nogo short hairpin RNAs decreased Nogo mRNA expression by 45% and 40%, respectively, compared with Nogo expression in spinal cord injury model rats transfected with the unrelated control short hairpin RNA （P 〈0.005）. The Nogo protein level was similarly decreased. Conclusions We were successful in specifically downregulating Nogo at the mRNA and protein levels by adenovirus-mediated delivery of short hairpin RNAs, both in vitro and in vivo. This confirms the effectiveness of RNA interference for the inhibition of Nogo gene expression and the efficiency of using adenovirus for delivery. Thus gene therapy may be an effective treatment for spinal cord injury.

关键词： spinal cord injury axonal regeneration RNA interference short hairpin RNA

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基于因子隐马尔可夫模型的负荷分解方法及灵敏度分析

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电力系统自动化 2016年第21期40卷 128-136页

作者：陈思运高峰刘烃翟桥柱管晓宏机械制造系统工程国家重点实验室(西安交通大学) 陕西省西安市710049 智能网络与网络安全教育部重点实验室(西安交通大学) 陕西省西安市710049

负荷分解是智能电网的关键技术,对负荷预测、需求侧管理及电网安全有重要意义。传统负荷分解方法的准确率受限于负荷特征的维度、采样频率和负荷的稳定性。文中提出了基于因子隐马尔可夫模型的负荷分解方法,利用该模型对负荷进行建模,对... 详细信息

负荷分解是智能电网的关键技术,对负荷预测、需求侧管理及电网安全有重要意义。传统负荷分解方法的准确率受限于负荷特征的维度、采样频率和负荷的稳定性。文中提出了基于因子隐马尔可夫模型的负荷分解方法,利用该模型对负荷进行建模,对Viterbi算法进行了扩展并求解负荷状态,进而基于整数规划实现对总负荷的最优分配。该方法对负荷数据的稳定性和采样频率不敏感,可适用于家居和工业电力用户。同时,深入研究了Viterbi算法求解最优状态与观测扰动之间的影响关系,并进一步得到最优状态对于当前观测的允许扰动范围,这对负荷分解最优状态的可靠性评估有重要意义。

关键词：隐马尔可夫模型因子隐马尔可夫模型负荷分解灵敏度分析

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An Improved Design of Carrier Phase Lock Loop Based On Four-Way Signal Processing

An Improved Design of Carrier Phase Lock Loop Based On Four-...

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第三届中国卫星导航学术年会

作者： Yuan gao, feng liu*, Teng Long School of Information and Electronics, Beijing Institute of Technology, Beijing, China

The carrier tracking loop which determines the performance of unaided GNSS receiver is always the weak link. Under a certain carrier noise ratio （CNR）, the threshold of carrier tracking loop is mainly affected by the dynamic stress. Costas phase lock loop （PLL） is one of most common carrier tracking loop, but it is too sensitive to the dynamic stress because of the limited frequency pull-in range. The frequency pull-in range of phase lock loop is determined by the maximum phase pull-in range. The phase pull-in range of classic Costas PLL based on two-way signal processing is just [-π/2, π/2], which is not good enough to track the carrier in dynamic environment. Therefore, a new four-way signal processing is proposed in this paper and applied into the Costas PLL, which can improve the phase pull-in range .In the proposed method, two way signal processing are added to the classic Costas PLL to construct four-way signal processing. The simulation results show that the proposed four-way signal processing PLL can significantly improve the dy- namic performance of the receiver.

关键词： carrier tracking loop phase lock loop phase pull-in range GNSS receiver

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稻曲病气象风险评估及适宜度等级预测技术

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植物保护 2017年第1期43卷 61-67页

作者：任义方高苹朱凤刘梅江苏省气象服务中心南京210008 江苏省植保站南京210046 江苏省气象台南京210008

为了弄清适宜稻曲病发生发展的气象条件以及对应的气象适宜度等级,提高水稻气象型病害防控能力,本文利用江苏省稻曲病大田调查资料,结合历史气象资料,通过评估发病敏感时段和致病风险,以及分析江苏省稻曲病最大成灾风险度出现日期以及... 详细信息

为了弄清适宜稻曲病发生发展的气象条件以及对应的气象适宜度等级,提高水稻气象型病害防控能力,本文利用江苏省稻曲病大田调查资料,结合历史气象资料,通过评估发病敏感时段和致病风险,以及分析江苏省稻曲病最大成灾风险度出现日期以及空间分布情况,指出8月下旬为稻曲病高发期,对于发病风险高且程度重的沿淮、沿江以及江淮之间地区需要加强病害防御。在此基础上,综合考虑不同连续致病天数对稻曲病流行的影响,利用最优化技术,构建了综合稻曲病指数,并划分气象条件适宜度等级。通过单站和多站检验发现该指数对"中等、大流行"发病实况的判定准确率极高,但容易高估"轻度流行"的程度。

关键词：水稻稻曲病风险评估综合稻曲病指数气象等级预测

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