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Lane-change path planning and control method for self-driving articulated trucks

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Journal of Intelligent and Connected Vehicles 2020年第2期3卷 49-66页

作者： tao Peng Xingliang Liu Rui Fang Ronghui Zhang Yanwei Pang tao Wang Yike Tong School of Electrical and Information Engineering Tianjin UniversityTianjinChina Joint Laboratory for Internet of Vehicles Ministry of Education-China Mobile Communications CorporationBeijingChina China Automotive Technology and Research Center Co.Ltd. TianjinChina Guangdong Key Laboratory of Intelligent Transportation System School of Intelligent Systems EngineeringSun Yat-sen UniversityZhuhaiChina Tianjin University of Technology and Education TianjinChina Zhejiang University of Technology HangzhouChina

Purpose–This study aims to develop an automatic lane-change mechanism on highways for self-driving articulated trucks to improve trafﬁc ***/methodology/approach–The authors proposed a novel safety lane-change path planning and tracking control method for articulated vehicles.A double-Gaussian distribution was introduced to deduce the lane-change trajectories of tractor and trailer coupling characteristics of intelligent vehicles and *** different steering and braking maneuvers,minimum safe distances were modeled and *** safety and ergonomics,the authors invested multilevel self-driving modes that serve as the basis of decision-making for vehicle ***,a combined controller was designed by feedback linearization and single-point preview optimization to ensure the path tracking and robust *** hardware in the loop simulation platform was built to verify the effectiveness of the designed ***–The numerical simulation results demonstrated the path-planning model feasibility and controller-combined decision mechanism effectiveness to self-driving *** proposed trajectory model could provide safety lane-change path planning,and the designed controller could ensure good tracking and robust stability for the closed-loop nonlinear ***/value–This is a fundamental research of intelligent local path planning and automatic control for articulated *** are two main contributions:theﬁrst is a more quantiﬁable trajectory model for self-driving articulated vehicles,which provides the opportunity to adapt vehicle and scene *** second involves designing a feedback linearization controller,combined with a multi-objective decision-making mode,to improve the comprehensive performance of intelligent *** study provides a valuable reference to develop advanced driving assistant system and intelligent control systems for self-driving articulated vehicles.

关键词： Feedback linearization Combined controller Double Gaussian distribution Lane-change path planning Preview optimization Self-driving articulated truck

White Matter Abnormalities in Major Depression Biotypes Identified by Diffusion Tensor Imaging

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Neuroscience Bulletin 2019年第5期35卷 867-876页

作者： Sugai Liang Qiang Wang Xiangzhen Kong Wei Deng xiao Yang xiaojing Li Zhong Zhang Jian Zhang Chengcheng Zhang Xin-min Li xiaohong Ma Junming Shao Andrew J. Greenshaw tao Li Mental Health Centre West China Hospital Sichuan University Chengdu 610041 China Huaxi Brain Research Centre West China Hospital Sichuan University Chengdu 610041 China Language and Genetics Department Max Planck Institute for Psycholinguistics 6525 XD Nijmegen Netherlands Big Data Research Center School of Computer Science and Engineering University of Electronic Science and Technology of China Chengdu 611731 China Department of Psychiatry University of Alberta Edmonton T6G 2B7 Canada

Identifying data-driven biotypes of major depressive disorder(MDD) has promise for the clarification of diagnostic heterogeneity. However, few studies have focused on white-matter abnormalities for MDD subtyping. This study included 116 patients with MDD and118 demographically-matched healthy controls assessed by diffusion tensor imaging and neurocognitive *** clustering was applied to the major fiber tracts, in conjunction with tract-based spatial statistics, to reveal white-matter alterations associated with *** and neurocognitive differences were compared between identified subgroups and healthy controls. With fractional anisotropy extracted from 20 fiber tracts, cluster analysis revealed 3 subgroups based on the patterns of abnormalities. Patients in each subgroup versus healthy controls showed a stepwise pattern of white-matter alterations as follows: subgroup 1(25.9% of patient sample),widespread white-matter disruption;subgroup 2(43.1% of patient sample), intermediate and more localized abnormalities in aspects of the corpus callosum and left cingulate;and subgroup 3(31.0% of patient sample),possible mild alterations, but no statistically significant tract disruption after controlling for family-wise error. The neurocognitive impairment in each subgroup accompanied the white-matter alterations: subgroup 1, deficits in sustained attention and delayed memory;subgroup 2, dysfunction in delayed memory;and subgroup 3, no significant deficits. Three subtypes of white-matter abnormality exist in individuals with major depression, those having widespread abnormalities suffering more neurocognitive impairments, which may provide evidence for parsing the heterogeneity of the disorder and help optimize typespecific treatment approaches.

关键词： Major depressive disorder Hierarchal clustering Diffusion tensor imaging Biotype Heterogeneity

复杂结构消声器消声特性的数值分析及结构优化

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振动工程学报 2007年第1期20卷 97-100页

作者：孟晓宏金涛浙江大学化工机械研究所浙江杭州310027

由于复杂结构消声器的内部声场比较复杂,平面波理论无法准确预测其分布,为了计算复杂结构消声器的消声特性,并进一步提高消声器的声学性能,在基本假设的前提下,合理处理进出口及壁面的边界条件,建立消声器内部声场的三维有限元模型,计... 详细信息

由于复杂结构消声器的内部声场比较复杂,平面波理论无法准确预测其分布,为了计算复杂结构消声器的消声特性,并进一步提高消声器的声学性能,在基本假设的前提下,合理处理进出口及壁面的边界条件,建立消声器内部声场的三维有限元模型,计算消声器的传递损失(TL)。然后,分析了不同的结构参数(隔板位置、内插管位置、进口管位置)对消声器的传递损失的影响,并优化了消声器的结构参数,有效地提高了消声器的消声性能,使得压缩机整机噪声降低了3.2 dB,验证了该分析方法的可行性,为复杂结构消声器的设计提供了参考依据。

关键词：消声器传递损失有限元法结构优化

Pregnancy Outcomes of Repeat Cesarean Section in Peking Union Medical College Hospital

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Chinese Medical Sciences Journal 2009年第3期24卷 147-150页

作者： Liang-kun Ma Na Liu Xu-ming Bian Li-rong Teng Hong Qi xiao-ming Gong Jun-tao Liu Jian-qiu Yang Department of Obstetrics and Gynecology Academy of Medical Sciences ＆ Peking Peking Union Medical College Hospital Chinese Union Medical College Beijing 100730 China

Objective To evaluate the effect of elective repeat cesarean section on the maternal and neonatal outcomes. Methods A retrospective clinic- and hospital-based survey was designed for comparing the maternal and neonatal outcomes of elective repeat cesarean section [RCS group （one previous cesarean section） and MRCS group （two or more previous cesarean sections）] and primary cesarean section （FCS group） at Peking Union Medical College Hospital from January 1998 to December 2007. Results The incidence of repeat cesarean section increased from 1.26% to 7.32%. The mean gestational age at delivery in RCS group （38.1±1.8 weeks） and MRCS group （37.3±2.5 weeks） were significantly shorter than that in FCS group （38.9±2.1 weeks, all P〈0.01）. The incidence of complication was 33.8% and 33.3% in RCS group and MRCS group respectively, and was significantly higher than that in FCS group （7.9%, P〈0.05）. Dense adhesion （13.5% vs. 0.4%, OR=7.156, 95% CI： 1.7-30.7, P〈0.01） and uterine rupture （1.0% vs. O,P〈0.05） were commoner in RCS group compared with FCS group. Neonatal morbidity was similar among three groups （P〉0.05）. Conclusions Repeat cesarean section is associated with more complicated surgery technique and increased frequency of maternal morbidity. However, the incidence of neonatal morbidity is similar to primary cesarean section.

关键词： repeat cesarean section pregnancy outcomes

Single-port laparoscopic radical prostatectomy： initial experience and technical points to reduce its difficulties

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Chinese Medical Journal 2011年第23期124卷 4092-4095页

作者： WEN Xing-qiao HUANG Wen-tao SITU Jie HU Cheng YE chun-wei GAO Xin Department of Urology Third Affiliated Hospital Sun Yat-sen University Guangzhou Guangdong 510630 China

Background Laparoendoscopic single-site surgery （LESS） approaches have been reported for treating various kidney and pelvic procedures, and are feasible and effective in selected patients. In this study, we aimed to present the initial experience and evaluate the efficacy of laparoscopic radical prostatectomy performed through a single incision using a multichannel port. Methods Between July 2010 and April 2011, six patients diagnosed with early stage prostate cancer underwent LESS radical prostatectomy （RP） in our institute. A multichannel port was inserted transperitoneally through a 2-cm umbilical incision. Specially articulating and flexible laparoscopic were used. Some technical tricks and points were applied during the operation to overcome the drawbacks and reduce the difficulties of this approach. Two continuous urethrovesical sutures in both sides were performed to complete both lateral aspects of anastomosis. The two ends of the suture threads were fixed by double Lapro-Clips, instead of the difficult knot-tying. Results Total operative time was （265-＋43） minutes. Mean blood loss was （230_＋65） ml. All cases were completed successfully, without conversion to open surgery or adding additional abdomen ports. No patient required a blood transfusion and no intraoperative complications occurred. The Foley catheter was removed at the 14th day （range 12th-16th） after surgery. At the 12th week of follow-up, all patients had an undetectable prostate-specific antigen level. Two patients used 2 or I pad for continence daily; other patients had achieved good continence. Conclusion In selected cases, LESS-RP is feasible and effective; these technic points and the flexible-articulating instruments are helpful to reduce the operation difficulties.

关键词： laparoendoscopic single-site surgery radical prostatectomy prostate cancer

Genetic and Epigenetic Understanding of the Seasonal Timing of Flowering

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Plant Communications 2020年第1期1卷 25-37页

作者： Yuehui He tao Chen xiaolin Zeng National Key Laboratory of Plant Molecular Genetics&Shanghai Center for Plant Stress Biology Chinese Academy of Sciences Center for Excellence in Molecular Plant SciencesShanghai 201602China

The developmental transition to flowering in many plants is timed by changing seasons,which enables plants to flower at a season that is favorable for seed *** plants grown at high latitudes perceive the seasonal cues of changing day length and/or winter cold(prolonged cold exposure),to regulate the expression of flowering-regulatory genes through the photoperiod pathway and/or vernalization pathway,and thus align flowering with a particular *** studies in the model flowering plant Arabidopsis thaliana have revealed that diverse transcription factors engage various chromatin modifiers to regulate several key flowering-regulatory genes including FLOWERING LOCUS C(FLC)and FLOWERING LOCUS T(FT)in response to seasonal ***,we summarize the current understanding of molecular and chromatin-regulatory or epigenetic mechanisms underlying the vernalization response and photoperiodic control of flowering in ***,the conservation and divergence of regulatory mechanisms for seasonal flowering in crops and other plants are briefly discussed.

关键词： vernalization photoperiodism flowering time FLOWERING LOCUS C FLOWERING LOCUS T chromatin modification

Some progress on understanding the Phanerozoic granitoids in China

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China Geology 2018年第1期1卷 84-108页

作者： tao Wang Ying Tong xiao-xia Wang Jian-ren Mao Hong-rui Zhang He Huang Shan Li Lei Guo Jian-jun Zhang Key Laboratory of Deep-Earth Dynamics Ministry of Natural ResourcesBeijing 100037China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Key Laboratory of Metallogeny and Mineral Assessment of Ministry of Natural Resources Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Nanjing center China Geological SurveyNanjing 210016China

There are large volumes of the Phanerozoic granitoid rocks in China and neighboring *** recent years,numerous new and precise U-Pb zircon ages have been published for these granitoids,and define many important magmatic events,such as ca.500 Ma granitoid events in the West Junggar,Altai orogens in the NW China,and Qinling orogen in the central *** ages accurately constrain the time of important early Paleozoic,late Paleozoic,early Mesozoic and late Mesozoic magmatic events of the northern,central,western,southern and eastern orogenic Mountains in *** occur various types of granitoids in China,such as talc-alkaline granite,alkali granite,highly-fractionated granite,leucogranite, adakite,and rapakivi *** granites are not only typical Proterozoic as in the North China Craton,but were also emplaced during Paleozoic and Mesozoic in the Kunlun-Qinling orogen,a part of the China Central Orogenic Belt (CCOB).Nd-Hf isotopic tracing and mapping show that granitoids inthe southern Central Asian Orogenic Belt (CAOB)in China (or the Northern China Orogenic Belt)are characterized predominantly by juvenile *** juvenile crust in this orogenic domain accounts for over 50% by area,distinguishing it from other orogenic belts in the world,and those in central (e.g.,Qinling),southwestem and eastern *** on a large amount of new age data,a preliminary granitoid and granitoid-tectonic maps of China have been preliminarily compiled,and an evolutionary framework of Phanerozoic granitoids in China and neighboring areas has been established from the view of assembly and breakup of continental *** ideas on granitoid tectonics has also been proposed and discussed.

关键词： Granitoids Zircon age Spatial-temporal distribution Radiogenic isotopes Orogen

Application of DSAPSO Algorithm in Distribution Network Reconfiguration with Distributed Generation

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Energy Engineering 2024年第1期121卷 187-201页

作者： Caixia tao Shize Yang Taiguo Li School of Automation and Electrical Engineering Lanzhou Jiaotong UniversityLanzhou730070China

With the current integration of distributed energy resources into the grid,the structure of distribution networks is becoming more *** complexity significantly expands the solution space in the optimization process for network reconstruction using intelligent ***,traditional intelligent algorithms frequently encounter insufficient search accuracy and become trapped in local *** tackle this issue,a more advanced particle swarm optimization algorithm is *** address the varying emphases at different stages of the optimization process,a dynamic strategy is implemented to regulate the social and self-learning *** Metropolis criterion is introduced into the simulated annealing algorithm to occasionally accept suboptimal solutions,thereby mitigating premature convergence in the population optimization *** inertia weight is adjusted using the logistic mapping technique to maintain a balance between the algorithm’s global and local search *** incorporation of the Pareto principle involves the consideration of network losses and voltage deviations as objective functions.A fuzzy membership function is employed for selecting the *** analysis is carried out on the restructuring of the distribution network,using the IEEE-33 node system and the IEEE-69 node system as examples,in conjunction with the integration of distributed energy *** findings demonstrate that,in comparison to other intelligent optimization algorithms,the proposed enhanced algorithm demonstrates a shorter convergence time and effectively reduces active power losses within the ***,it enhances the amplitude of node voltages,thereby improving the stability of distribution network operations and power supply ***,the algorithm exhibits a high level of generality and applicability.

关键词： Reconfiguration of distribution network distributed generation particle swarm optimization algorithm simulated annealing algorithm active network loss

Entransy: its physical basis, applications and limitations

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Chinese Science Bulletin 2014年第36期59卷 5309-5323页

作者： Xue-tao Cheng Xin-Gang Liang Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua University

In this paper, the physical basis and application conditions of the entransy theory are reviewed and discussed. Entransy can be obtained from the analogy between heat and electrical conductions. It is a state value and the‘‘potential energy'' of heat. From the viewpoint of thermomass, it reflects the thermal energy of the thermomass in an object. Furthermore, it was also related to the microstate number and is a single value function of the microstate number. The concepts of entransy, entransy flux and entransy dissipation can be used to express the least action of heat transfer. The entransy balance equations for heat transfer and thermodynamic processes and their applications to thermal systems are also reviewed. The differences between the entransy theory, constructal theory, entropy generation minimization, exergy analyses method, principle of uniformity of temperature difference field and field synergy(coordination) principle are also discussed. The entransy theory is different from the other discussed theories. The limitations of the entransy theory are also discussed.

关键词：应用程序物理基础微观状态数热力学过程平衡方程构形理论火用分析热系统