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模糊PID复合控制算法改进及应用

东北大学学报（自然科学版） 2009年第2期30卷 274-278页

作者：李丽娜柳洪义罗忠孙一兰东北大学机械工程与自动化学院辽宁沈阳110004

针对常规模糊PID复合控制算法的不足,在分析了其控制特性后,提出了相应的改进算法.采用基于梯形隶属函数的模糊切换算法以及基于变论域和仿人智能思想的量化因子和比例因子的在线自调整算法实现了自适应模糊PID复合控制,并将此改进算法... 详细信息

针对常规模糊PID复合控制算法的不足,在分析了其控制特性后,提出了相应的改进算法.采用基于梯形隶属函数的模糊切换算法以及基于变论域和仿人智能思想的量化因子和比例因子的在线自调整算法实现了自适应模糊PID复合控制,并将此改进算法用于PCR芯片智能温度控制系统中,使控制系统获得了良好的动态特性和稳态性能、较强的鲁棒性及适应性.实验结果表明,其控制品质远优于常规模糊PID控制和基本模糊控制.

关键词：模糊PID复合控制模糊切换变论域仿人智能量化因子比例因子在线自调整聚合酶链反应

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基于具身认知的商业街互动装置设计策略探究

包装工程 2024年第18期45卷 420-431页

作者：孙元煦易西多武汉理工大学武汉430070

目的在具身认知的视角下探究商业街中互动装置设计的机会点,满足商业街日益增长的临场体验需求。方法首先,通过具身认知理论及其设计应用综述发掘具身认知理论对当前设计在知觉向度、动觉向度和反思向度上提出的新要求;其次,引入消费社... 详细信息

目的在具身认知的视角下探究商业街中互动装置设计的机会点,满足商业街日益增长的临场体验需求。方法首先,通过具身认知理论及其设计应用综述发掘具身认知理论对当前设计在知觉向度、动觉向度和反思向度上提出的新要求;其次,引入消费社会理论探讨商业街互动装置设计具身转向的应用价值,通过调研实际案例归纳了互动装置的互动方式,并绘制用户体验地图以挖掘商业街互动装置在前期引流、中期互动和后期反馈上的设计机会点,发现其具身交流特质于商业营销的意义;最后,基于前期研究得出体验者在感官、运动和情境三方面的具身认知需求并提出商业街互动装置的设计策略。结论互动装置围绕“形式-移觉”“时间-空间”“内容-编码”展开的具身化设计,能够营造商业街的消费氛围、增强沉浸式体验,为具身认知在商业营销中的设计应用提供了可行策略。

关键词：具身认知城市商业街互动装置消费氛围设计策略

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Picosecond electrical response in graphene/MoTe_(2) heterojunction with high responsivity in the near infrared region

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Fundamental Research 2022年第3期2卷 405-411页

作者： Zhouxiaosong Zeng Kai Braun Cuihuan Ge Martin Eberle Chenguang Zhu Xingxia sun Xin Yang Jiali yi Delang Liang Yufan Wang Lanyu Huang Ziyu Luo Dong Li Anlian Pan Xiao Wang School of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Physical and Theoretical Chemistry and LISA+ University of TübingenAuf der Morgenstelle 18Tübingen 72076Germany Key Laboratory for Micro-Nano Physics and Technology of Hunan Province College of Materials Science and EngineeringHunan UniversityChangsha 410082China

Understanding the fundamental charge carrier dynamics is of great significance for photodetectors with both high speed and high *** based on two-dimensional(2D)transition metal dichalcogenides can exhibit picosecond photoresponse ***,2D materials naturally have low absorption,and when increasing thickness to gain higher responsivity,the response time usually slows to nanoseconds,limiting their photodetection ***,by taking time-resolved photocurrent measurements,we demonstrated that graphene/MoTe_(2) van der Waals heterojunctions realize a fast 10 ps photoresponse time owing to the reduced average photocurrent drift time in the heterojunction,which is fundamentally distinct from traditional Dirac semimetal photodetectors such as graphene or Cd_(3)As_(2) and implies a photodetection bandwidth as wide as 100 ***,we found that an additional charge carrier transport channel provided by graphene can ef-fectively decrease the photocurrent recombination loss to the entire device,preserving a high responsivity in the near-infrared *** study provides a deeper understanding of the ultrafast electrical response in van der Waals heterojunctions and offers a promising approach for the realization of photodetectors with both high responsivity and ultrafast electrical response.

关键词： Two-dimension material Graphene/MoTe_(2)heterojunction Near infrared photodetector Scanning photocurrent microscopy Time-resolved photocurrent

Study of brain-derived neurotrophic factor gene transgenic neural stem cells in the rat retina

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Chinese Medical Journal 2009年第14期122卷 1642-1649页

作者： ZHOU Xue-mei YUAN Hui-ping WU Dong-lai ZHOU Xin-rong sun Da-wei LI Hong-yi SHAO Zheng-bo Department of Ophthalmology Second Affiliated Hospital of Harbin Medical University Harbin Heilongjiang 150086 China Harbin Veterinary Research Institute China Agricultural Academy of Science Harbin Heilongjiang 150001 China

Background Neural stem cells （NSCs） transplantation and gene therapy have been widely investigated for treating the cerebullar and myelonic injuries, however, studies on the ophthalmology are rare. The aim of this study was to investigate the migration and differentJatJon of brain-derived neurotrophic factor （BDNF） gene transgenic NSCs transplanted into the normal rat retinas. Methods NSCs were cultured and purified in vitro and infected with recombinant retrovirus pLXSN-BDNF and pLXSN respectively, to obtain the BDNF overexpressed NSCs （BDNF-NSCs） and control cells （p-NSCs）. The expression of BDNF genes in two transgenic NSCs and untreated NSCs were measured by fluorescent quantitative polymerase chain reaction （FQ-PCR） and enzyme-linked Jmmunosorbent assay （ELISA）. BDNF-NSCs and NSCs were infected with adeno-associated viruses-enhanced green fluorescent protein （AAV-EGFP） to track them in vivo and served as donor cells for transplantation into the subretinal space of normal rat retinas, phosphated buffer solution （PBS） served as pseudo transplantation for a negative control. Survival, migration, and differentiation of donor cells in host retinas were observed and analyzed with Heidelberg retina angiograph （HRA） and immunohistochemistry, respectively. Results NSCs were purified successfully by limiting dilution assay. The expression of BDNF gene in BDNF-NSCs was the highest among three groups both at mRNA level tested by FQ-PCR （P 〈0.05） and at protein level measured by ELISA （P 〈0.05）, which showed that BDNF was overexpressed in BDNF-NSCs. The results of HRA demonstrated that graft cells could survive well and migrate into the host retinas, while the immunohistochemical analysis revealed that transplanted BDNF-NSCs differentiated into neuron more efficiently compared with the control NSCs 2 months after transplantation. Conclusions The seed cells of NSCs highly secreting BDNF were established. BDNF can promote NSCs to migrate and differentiate into neural cells in

关键词： neural stem cells brain-derived neurotrophic factor transplantation Heidelberg retina angiograph immunohistochemistry

快速高分离度液相色谱-质谱联用方法筛选Tau蛋白激酶2抑制剂

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高等学校化学学报 2013年第5期34卷 1111-1114页

作者：陈宁孙一越皓刘淑莹中国科学院长春应用化学研究所长春质谱中心长春130022 中国科学院大学北京100049 长春中医药大学吉林省人参科学研究院长春130117

建立了测定Tau蛋白激酶2(Tau protein kinase 2,TPK2)催化反应产物磷酸化十肽(PKpTPKKAKKL)的快速高分离度液相色谱-质谱方法(RRLC/MS)用于筛选TPK2抑制剂.反应溶液总体积为50μL,将终浓度为20 nmol/L的TPK2与终浓度为5μmol/L的底物十... 详细信息

建立了测定Tau蛋白激酶2(Tau protein kinase 2,TPK2)催化反应产物磷酸化十肽(PKpTPKKAKKL)的快速高分离度液相色谱-质谱方法(RRLC/MS)用于筛选TPK2抑制剂.反应溶液总体积为50μL,将终浓度为20 nmol/L的TPK2与终浓度为5μmol/L的底物十肽(PKTPKKAKKL)于30℃反应30 min,用等体积乙腈终止反应并加入终浓度为1μmol/L的磷酸化十肽(PKpTPKKAKKV)作为内标,采用Agilent SB-C18色谱柱,以乙腈-水为流动相梯度洗脱分离后,用RRLC/MS进行定性及定量分析.该方法可通过精确定量一定时间内的酶促反应产物来反映酶活性被抑制的程度,作为TPK2抑制剂的筛选方法,本方法具有简单、灵敏、快速的优点,能够避免光谱法筛选可能产生的假阳性结果,可用于TPK2的先导化合物的高通量筛选.

关键词：阿尔兹海默病 Tau蛋白激酶快速高分离度液相色谱-质谱

Comparision between portosystemic shunts and endoscopic therapy for prevention of variceal re-bleeding:a systematic review and meta-analysis

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Chinese Medical Journal 2019年第9期132卷 1087-1099页

作者： Guang-Peng Zhou Li-ying sun Lin Wei Wei Qu Zhi-Gui Zeng ying Liu yi-Zhou Jiang Zhi-Jun Zhu Liver Transplantation Center Beijing Friendship HospitalCapital Medical UniversityBeijing 100005China Clinical Center for Pediatric Liver Transplantation Capital Medical UniversityBeijing 100005China National Clinical Research Center for Digestive Diseases Beijing 100005China Intensive Care Unit Beijing Friendship HospitalCapital Medical UniversityBeijing 100005China

Background:Portosystemic shunts,including surgical portosystemic shunts and transjugular intra-hepatic portosystemic shunt (TIPS),may have benefit over endoscopic therapy (ET) for treatment of variceal bleeding in patients with cirrhotic portal hypertension;however,whether there being a survival benefit among them remains *** study was to compare the effect of three above-mentioned therapies on the short-term and long-term survival in patient with ***:Using the terms "variceal hemorrhage or variceal bleeding or variceal re-bleeding" OR "esophageal and gastric varices" OR "portal hypertension" and "liver cirrhosis," the Cochrane Central Register of Controlled Trials,PubMed,Embase,and the references of identified trials were searched for human randomized controlled trials (RCTs) published in any language with full texts or abstracts (last search June 2017).Risk ratio (RR) estimates with 95% confidence interval (CI) were calculated using random effects model by Review *** quality of the included studies was evaluated using the Cochrane Collaboration’s tool for the assessment of the risk of ***:Twenty-six publications comprising 28 RCTs were included in this *** studies included a total of 2845 patients:496 (4 RCTs) underwent either surgical portosystemic shunts or TIPS,1244 (9 RCTs) underwent either surgical portosystemic shunts or ET,and 1105 (15 RCTs) underwent either TIPS or *** was no significant difference in overall mortality and 30-day or 6-week survival among three *** with TIPS and ET,separately,surgical portosystemic shunts were both associated with a lower bleeding-related mortality (RR = 0.07,95% CI = 0.01–0.32;P<0.001;RR = 0.17,95% CI = 0.06–0.51,P<0.005) and rate of variceal re-bleeding (RR = 0.23,95% CI = 0.10–0.51,P<0.001;RR = 0.10,95% CI = 0.04–0.24,P<0.001),without a significant difference in the rate of postoperative hepatic encephalopathy (RR = 0.52,95% CI = 0.25–1.00,P = 0.1

关键词： Portosystemic shunts Endoscopic therapy Variceal rebleeding Cirrhosis Meta-analysis

Effect of specimen thickness on Mode Ⅱ fracture toughness of rock

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Journal of Central South University of Technology 2001年第2期8卷 114-119页

作者： RAO Qiu hua 1,sun Zong qi 1,WANG Gui yao 2,XU Ji cheng 3,ZHANG Jing yi 3 (1.College of Resources, Environment and Civil Engineering, Central South University, Changsha 410083, China 2.River and Sea Department, Changsha Communications Univer College of Resources Environment and Civil Engineering Central South University Changsha China River and Sea Department Changsha Communications University Changsha China Open Lab of Mechanics Central South University Changsha China

Anti symmetric four point bending specimens with different thickness, without and with guiding grooves, were used to conduct Mode Ⅱ fracture test and study the effect of specimen thickness on Mode Ⅱ fracture toughness of rock. Numerical calculations show that the occurrence of Mode Ⅱ fracture in the specimens without guiding grooves (when the inner and outer loading points are moved close to the notch plane) and with guiding grooves is attributed to a favorable stress condition created for Mode Ⅱ fracture, i.e. tensile stress at the notch tip is depressed to be lower than the tensile strength or to be compressive stress, and the ratio of shear stress to tensile stress at notch tip is very high. The measured value of Mode Ⅱ fracture toughness K ⅡC decreases with the increase of the specimen thickness or the net thickness of specimen. This is because a thick specimen promotes a plane strain state and thus results in a relatively small fracture toughness.

关键词： Mode Ⅱ fracture toughness rock fracture stress analysis specimen thickness

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多周期交变载荷工况下地下储气库密封性评价

科学技术与工程 2016年第6期16卷 23-28页

作者：孙莎莎唐立根中国地质大学(北京)能源学院北京100083 中国石油勘探开发研究院廊坊分院廊坊065007

随着我国引进天然气资源的高速增长,在中亚管道投运的基础上,中俄西线天然气管道建设加快提速,急需寻找建设特大规模型地下储气库保障进口天然气供需平稳安全运行。克拉2气田是西气东输一线的气源地,距离中亚、中俄西线管线中国口岸较近... 详细信息

随着我国引进天然气资源的高速增长,在中亚管道投运的基础上,中俄西线天然气管道建设加快提速,急需寻找建设特大规模型地下储气库保障进口天然气供需平稳安全运行。克拉2气田是西气东输一线的气源地,距离中亚、中俄西线管线中国口岸较近,改建储气库将在季节调峰、安全平稳保供和战略储备方面发挥重要作用。为了讨论克拉2改建储气库的密封性,从盖层、断层、裂缝、溢出点、储层底板和井的完整性等方面,通过考虑逆断层的活动情况,使用断面正应力的最小值评价断层的密封性,将储层底板密封性和井的完整性纳入储气库评价体系,形成了考虑原始圈闭、钻采工程和多周期交变载荷工况下的储气库密封性评价体系。认为克拉2气田通过调整开发政策在开发末期改建为地下储气库可行,为改建储气库提供依据。

关键词：储气库密封性断面正应力储层底板井的完整性评价体系

Study on Differences in Procyanidine Content Between Muscat Hamburg Grape From Different Producing Areas

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Agricultural Biotechnology 2019年第1期8卷 176-179页

作者： Wen XU Qiusheng CHEN Zhe YANG Qiang ZHANG Rui sun Fang SU yi PEI College of Horticulture Tianjin Agricultural University Tianjin Institute of Agricultural Quality Standard and Testing Technology

[Objectives] This study was conducted to analyze the differences in procyanidine content in grapes caused by different producing areas. [Methods]With Muscat Hamburg grape from different producing areas as an experimental material,procyanidine content was determined by n-butanol-hydrochloric acid colorimetry. [Results] The procyanidins contents in different parts of the same variety ranked as grape seed > grape skin > grape flesh. The procyanidins contents in grapes from different producing areas were in order of Changli County,Hebei Province > Dazeshan Town,Shandong Province > Hangu District,Tianjin City.[Conclusions]The procyanidins contents in Muscat Hamburg grapes from different producing areas differ to a certain degree.

关键词： Muscat Hamburg grape Production areas Proanthocyanidins Differences