检索结果-南通市图书馆

基于K-means和主成分分析的京张体育文化旅游带冰雪运动旅游市场研究

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

河北北方学院学报（社会科学版） 2024年第2期40卷 16-19,88页

作者：王光军王姣姣赵小勇商万军杨义风河北北方学院公共体育部河北张家口075000 张家口旅投国际旅行社河北张家口075000 张家口市第一中学体育组河北张家口075000 河北北方学院经济管理学院河北张家口075000

使用问卷调查、K-means聚类分析和主成分因子分析等方法对后冬奥时期京张体育文化旅游带的冰雪运动旅游市场进行分析发现,该市场可细分为青年冰雪爱好者、家庭亲子游客、中老年休闲游客和高端商务游客等类别。其中:青年和家庭市场为主力... 详细信息

使用问卷调查、K-means聚类分析和主成分因子分析等方法对后冬奥时期京张体育文化旅游带的冰雪运动旅游市场进行分析发现,该市场可细分为青年冰雪爱好者、家庭亲子游客、中老年休闲游客和高端商务游客等类别。其中:青年和家庭市场为主力,市场需求集中在专业冰雪设施服务和冰雪文化体验等方面。据此,提出提升冰雪运动品质安全、丰富文化内涵和满足个性化需求等策略,以挖掘市场潜力,促进该地区冰雪旅游经济的可持续发展。

关键词：冰雪运动旅游市场细分市场定位 K-means聚类分析主成分因子分析

基于改进广义S变换时频分析的“板状”断控油藏油柱高度预测

在线全文

学校读者我要写书评

暂无评论

物探与化探 2024年第3期48卷 768-776页

作者：袁晓满李相文张洁但光箭卢忠沅韩重阳张磊许建洋中国石油集团塔里木油田公司哈得采油气管理区新疆库尔勒841001 中国石油集团东方地球物理勘探有限责任公司研究院新疆库尔勒841000 中油奥博(成都)科技有限责任公司四川成都611730

塔里木盆地北部坳陷碳酸盐岩断控领域油气资源丰富。断控“板状”油藏油水界面的识别是该类油藏效益开发的关键工作。钻井探测油藏油水界面的成本高、工程实现难度大,而采用地球物理的方法识别油水界面是一种高效措施。文章提出一种基... 详细信息

塔里木盆地北部坳陷碳酸盐岩断控领域油气资源丰富。断控“板状”油藏油水界面的识别是该类油藏效益开发的关键工作。钻井探测油藏油水界面的成本高、工程实现难度大,而采用地球物理的方法识别油水界面是一种高效措施。文章提出一种基于广义S变换时频分析的应用方法,通过大量过井地震道时频分析结果与开发动态分析数据联合分析,发现地震资料主频随深度/时间的变化与油层厚度具有正相关关系,提出采用地震道时频道集能量包络异常拐点判别油水界面的思路。实验表明,针对“板状”油藏,当油柱厚度OCH250 m时,油层厚度可靠。应用表明,在富满油田某区某断裂破碎带预测油层厚度主体为200~520 m,与当地开发实际相符,可指导开发实践。

关键词：断裂破碎带断控油藏油层厚度地震探测时频分析塔里木盆地

BrФnsted Acidic Ionic Liquids: Novel Efficient, Cost-effective and Reusable Solvent-catalysts for Ritter Reaction

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2010年第3期26卷 384-388页

作者： JIANG feng LIN Ying-jie DUAN Hai-feng LI Zong-han CAO Jun-gang LIANG Da-peng Department of Organic Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China

Several Bronsted acidic ionic liquids（ILs） were synthesized and used as dual solvent-catalysts for the Ritter reaction of benzonitrile with tert-butanol. In particular, IL11（[NSPTEA][OTF]） showed excellent catalytic activity for the Ritter reaction. In the presence of IL11, various nitriles and tertiary alcohols as well as secondary alcohols were converted smoothly to the corresponding amides in good to excellent yields. In addition, this cost-effective ionic liquid [NSPTEA][OTF] was easily separated from the reaction mixture by extraction with a small amount of water, and was recycled five times without any significant loss in activity.

关键词： Bronsted acidic ionic liquid Ritter reaction Solvent-catalyst Article ID

Market based framework for multiple AUVs cooperation

在线全文

学校读者我要写书评

暂无评论

Journal of Marine Science and Application 2005年第2期4卷 7-12页

作者： YOU guang-xin PANG Yong-jie JIANG Da-peng School of Ship Building Engineering Harbin Engineering University Harbin 150001 China

A“Market” based framework for multiple AUVs team is introduced in this *** is a distributed meta-level task allocation framwork. The formulation and the basic concepts of the “Market” such as “goods” and “price” are discussed first, then the basic algorithm of the “auction”. The loosely coupled v-MDTSP tasks are considered as an example of the task allocation mission. A multiple AUV team controller and a detailed algorithm are developed for such applications. The simulation results show that the controller has the advantages such as robustness and low complexity and it can achieve better optimization results than the classical central controller (such as GA) in some tasks. And the comparison of two different local solvers also implies that we should get the reasonable task allocation even not using the high quality algorithm, which can considerably decrease the cooperation computation.

关键词： autonomous underwater vehicle (AUV) cooperation “Market” based framework

Novel rhino-like SHJH^(hr) mice with thyroid dysfunction

在线全文

学校读者我要写书评

暂无评论

Zoological Research 2021年第6期42卷 734-738页

作者： Yong-Chao Li Jin-feng Gao Ya-Lun Guan Xiao-Yue Wei Xue-Jiao Li Yun-feng Li Zhong-Qiang Huang Shu-Hua Liu Ge Li Ping Xu guang-Jin Pan Yu Zhang guangdong Provincial Key Laboratory of Laboratory Animals Guangdong Laboratory Animals Monitoring InstituteGuangzhouGuangdong 510663China Key Laboratory of Regenerative Biology South China Institute for Stem Cell Biology and Regenerative MedicineGuangzhou Institutes of Biomedicine and HealthChinese Academy of SciencesGuangzhouGuangdong 510530China School of Pharmacy Guangdong Pharmaceutical UniversityGuangzhouGuangdong 510006China Shanghai Jihui Laboratory Animal Care Co. Ltd.Shanghai 201611China

A new Hairless(Hr)gene mutant mouse line(SHJH^(hr))was identified,which showed hairless skin in adult individuals as reported in rhino *** Hr gene mutant identification with polymerase chain reaction(PCR)amplification and sequencing,seven mutants were identified,including nonsense mutant site 2134C→T(R467X),which produced a truncated Hr *** activity and heart rate were measured using a metabolic cage and blood pressure instrument,*** SHJH^(hr) mice showed a strong metabolic rate,high heart rate,and low blood *** analysis of the thyroid gland of SHJH^(hr) mice showed abnormal follicular structure and hypertrophic *** to ICR mice,thyroid function in 4-month-old SHJH^(hr) mice showed lower thyroid stimulating hormone(TSH)levels,and in 9-month-old SHJH^(hr) mice showed significantly higher TSH and thyroid hormone *** data indicate that SHJH^(hr) mice may be in a hyperthyroid state with increasing ***,based on the above results,we successfully established a novel mouse model with thyroid dysfunction.

关键词： instrument dysfunction stimulating

在线全文

学校读者我要写书评

暂无评论

燃爆弹跳驱动器仿真与试验研究（英文）

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2017年第10期18卷 831-840页

作者： Yun-guang LUAN Hua-ming WANG Dong-biao ZHAO Yang WANG feng-hong CHEN College of Mechanical and Electronical Engineering Nanjing University of Aeronautics and Astronautics Department of Mechatronics Suzhou Vocational Institute of Industrial Technology State Key State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang University

目的:研究燃爆弹跳驱动器热-动力学模型,分析驱动器的输出性能,并通过试验验证驱动器热-动力学模型的正确性。创新点:1.建立了燃爆弹跳驱动器热-动力学模型,得到燃爆弹跳驱动器的相关输出参数随时间的变化规律;2.通过理论仿真与试验测... 详细信息

目的:研究燃爆弹跳驱动器热-动力学模型,分析驱动器的输出性能,并通过试验验证驱动器热-动力学模型的正确性。创新点:1.建立了燃爆弹跳驱动器热-动力学模型,得到燃爆弹跳驱动器的相关输出参数随时间的变化规律;2.通过理论仿真与试验测试分析了驱动器的输出性能。方法:1.根据对燃爆弹跳机器人工作过程分析,推导出燃爆弹跳驱动器工作过程中的动力学模型,并对锁紧力与弹簧刚度参数进行测试;2.根据热-动力学模型推导出燃烧室内压力随时间变化的函数;3.通过试验测试驱动器驱动弹跳过程中压力和位移随时间的变化曲线,将测试结果与热-动力学模型仿真的结果进行比较。结论:1.建立了燃爆弹跳驱动器的热-动力学模型,得到了驱动器的输出性能参数;2.试验测试结果与仿真计算结果吻合,证明了驱动器热-动力学模型的正确性。

关键词：热-动力学模型燃爆驱动器仿真分析试验分析输出性能

Weak Anti-Localization and Quantum Oscillations in Topological Crystalline Insulator PbTe

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2017年第2期34卷 67-70页

作者： Ke-jie Wang Wei Wang Min-Hao Zhang Xiao-Qian Zhang Pei Yang Bo Liu Ming Gao Da-Wei Huang Jun-Ran Zhang Yu-jie Liu Xue-feng Wang feng-Qiu Wang Liang He Yong-Bing Xu Rong Zhang Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials Jiangsu Provincial Key Laboratory for NanotechnologyCollaborative Innovation Center of Advanced MicrostructuresSchool of Electronic Science and EngineeringNanjing UniversityNanjing 210093

Topological crystalline insulators （TCIs） have attracted worldwide interest since their theoretical predication and have created exciting opportunities for studying topological quantum physics and for exploring spintronic appli- cations. In this work, we successfully synthesize PbTe nanowires via the chemical vapor deposition method and demonstrate the existence of topological surface states by their 2D weak anti-localization effect and Shubnikov-de Haas oscillations. More importantly, the surface state contributes ~61% of the total conduction, suggesting dom- inant surface transport in PbTe nanowires at low temperatures. Our work provides an experimental groundwork for researching TCIs and is a step forward for the applications of PbTe nanowires in spintronic devices.

关键词： Weak Anti-Localization and Quantum Oscillations in Topological Crystalline Insulator PbTe length

Synthesis, Crystal Structure and Second-order Optical Nonlinearity of 6-Nitro-[1,10]phenanthroline-1-ium Nitrate, [HphenNO2]^+NO_3^-

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2003年第5期22卷 533-538页

作者： CHEN Yu-Hong BEI feng-Li YANG Xu-jie LU Lu-De WANG Xin① (Materials Chemistry Laboratory, Nanjing University of Science & Technology, Nanjing 210094, China) Materials Chemistry Laboratory Nanjing University of Science & Technology Nanjing 210094

The title compound [HphenNO2]+NO3- has been prepared and characterized by elemental analysis, electronic absorption spectroscopy, TG/DTA, IR, 1H and 13C NMR spectro- scopy. Single-crystal X-ray structure determination of the title compound was also carried out. It crystallizes in monoclinic, space group Cc with a = 13.861(3), b = 10.142(2), c = 8.7320(17) ? b = 103.70(3)? C12H8N4O5, Mr = 288.22, V = 1192.6(4) 3, Z = 4, Dc = 1.605 g/cm3 , F(000) = 592, (MoK) = 0.129 mm-1, R = 0.0439, wR = 0.1125 and GOF =1.114. In the crystal lattice, the molecules create a network structure through hydrogen bonds. The second order optical non- linearity was performed by quantum chemical method, showing the title compound has higher molecular hyper polarizability value (?= 24.66×10-30 esu).

关键词： crystal structure 6-nitro-[1 10]phenanthrolin-1-ium nitrate characterization second-order non-linearity

在线全文

学校读者我要写书评

暂无评论

沥青自愈合性能评价指标修正及应用

中国公路学报 2019年第11期32卷 103-108页

作者：罗蓉石晨光冯光乐武汉理工大学交通学院湖北武汉430063 湖北省公路工程技术研究中心湖北武汉430063 湖北省交通运输厅工程质量监督局湖北武汉430014

通过对比和分析现有沥青自愈合指标的不足,以模量下降速率重新定义自愈合指标,该指标值越小说明沥青材料的自愈合性能越优。采用动态剪切流变仪(Dynamic Shear Rheometer, DSR)对7种沥青进行不同间歇时间和不同损伤度下间歇加载式的自... 详细信息

通过对比和分析现有沥青自愈合指标的不足,以模量下降速率重新定义自愈合指标,该指标值越小说明沥青材料的自愈合性能越优。采用动态剪切流变仪(Dynamic Shear Rheometer, DSR)对7种沥青进行不同间歇时间和不同损伤度下间歇加载式的自愈合试验,以毛细扩散理论下的自愈合行为方程对自愈合指标进行线性拟合,获得代表沥青瞬时自愈合和后期自愈合的参数,用以研究沥青的自愈合性能。结果表明:沥青的自愈合指标随着间歇时间的增大而减小,但其变小的速率趋于缓慢;7种沥青在不同损伤度下的自愈合指标值与间歇时间的0.25次方存在较好的线性正相关,判定系数R^2均在0.85以上,无论是基质沥青还是改性沥青,新指标都具有较好的适用性;SBS改性沥青的瞬时自愈合优于基质沥青,随着添加到SBS沥青中改性剂掺量的增大,改性沥青的瞬时自愈合表现出先弱后强的趋势,而这7种沥青的后期自愈合性能与其瞬时自愈合性能正好相反,代表瞬时自愈合和后期自愈合的参数具有较好的负相关,说明瞬时自愈合性能优的沥青其后期自愈合性能较差。

关键词：道路工程自愈合指标间歇式自愈合试验沥青瞬时自愈合后期自愈合