检索结果-南通市图书馆

基于加权隶属度矩阵的岩体质量优化分级及支护研究

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

采矿与岩层控制工程学报 2024年第2期6卷 48-57页

作者：李福佳刘艳章秦绍兵于佳兴张迪叶涛武汉科技大学资源与环境工程学院湖北武汉430081 冶金矿产资源高效利用与造块湖北省重点实验室湖北武汉430081 中钢集团武汉安全环保研究院有限公司湖北武汉430081

巷道围岩质量分级是巷道围岩稳定性分析、合理支护设计与施工的基础。提高分级结果的准确性,是提升支护效果和巷道围岩稳定性的关键途径。以RMR法为基础,以某一测点的分级因素指标值为例,构建RMR法各分级指标的隶属度矩阵,再结合熵值法... 详细信息

巷道围岩质量分级是巷道围岩稳定性分析、合理支护设计与施工的基础。提高分级结果的准确性,是提升支护效果和巷道围岩稳定性的关键途径。以RMR法为基础,以某一测点的分级因素指标值为例,构建RMR法各分级指标的隶属度矩阵,再结合熵值法确定分级指标的权重,得到加权隶属度矩阵,构造优化后的评分公式,进行指标优化评分和围岩质量分级,然后根据围岩质量分级结果及松动圈监测结果设计支护参数,利用FLAC3D进行模拟计算以巷道围岩塑性区体积和顶底板收敛量为评价指标,研究优化前后的支护效果。研究结果表明:经过优化后的指标评分和围岩等级更加准确,巷道支护参数设计更加合理,数值模拟结果显示其能有效地提升围岩的稳定性,并将优化后的支护设计参数应用于工程,取得了良好的效果。研究成果可有效解决巷道围岩分级因素指标值位于分级边界或分级跨度大的问题,为矿山岩体质量分级与支护设计提供参考。

关键词：隶属度熵值法岩体质量分级围岩稳定性巷道支护

维普期刊数据库博看期刊

同方期刊数据库

基于ARIMA构建SWECPX模型解决电商需求预测问题

在线全文

学校读者我要写书评

暂无评论

中国商论 2024年第8期 29-32页

作者：向俊坤郁佳幸高贺孙浩翔中国人民解放军空军预警学院湖北武汉430012 上海交通大学上海200240

本文针对电商需求预测问题,基于促销节日因素S(Sale)和仓库因素C(Category),借助Matlab、Excel软件进行数据预处理,以ARIMA时间序列模型为核心,建立SWECPX(Sale Ware Effect Category Product X)模型,使用Matlab软件中的X-12-ARIMA选项等方法进行求解,实现了对商品需求量的准确预测,取得较好的1-wrmape指标测试效果。本文最大的创新点是提出了SWECPX模型,对影响商品需求量的要素S和C进行区分和求解,使对商品需求量预测更加精确,1-wrmape值较高。当每日的商品需求量处于较低水平时,预测效果的提升尤为显著,其预测值几乎与实际值相同。因此,我们期望SWECPX模型可以为电商仓储平台的决策提供切实的参考和借鉴。

关键词： ARIMA模型 SWECPX模型时间序列电商需求预测电商平台

维普期刊数据库博看期刊

Angioarchitecture and prognosis of pediatric intracranial pial arteriovenous fistula

在线全文

学校读者我要写书评

暂无评论

Stroke & Vascular Neurology 2023年第4期8卷 292-300页

作者： Jingwei Li Zhenlong Ji jiaxing yu Jian Ren Fan Yang Lisong Bian Xinglong Zhi Guilin Li Hongqi Zhang Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina National Center for Neurological Disorders BeijingChina China International Neuroscience Institute BeijingChina Department of Neurosurgery Affiliated Hospital of Beihua UniversityJilin provinceChina Department of Neurosurgery Beijing United Family HospitalBeijingChina Department of Neurosurgery Beijing Haidian HospitalBeijingChina

Objective Pial arteriovenous fistulas(PAVFs)are rare and mostly observed in ***,the overall angioarchitecture,clinical features,treatments and long-term prognosis for pediatric patients remain *** Clinical data of consecutive 42 pediatric PAVFs were documented and *** to the differences of age distribution and clinical features,they were split into a younger group(≤3 years old;20 cases)and an older group(3-14 years old;22 cases).Results Their mean age was 4.9±3.9 years,and the mean preoperative modified Rankin Scale(mRS)score was 1.64±*** patients(33.3%)were asymptomatic,followed by epilepsy(21.4%),intracranial haemorrhage(16.7%),hydrocephalus(9.5%),developmental delay(7.1%),intermittent headache(7.1%)and congestive heart failure(4.8%).Annual bleeding rate and rebleeding rate before treatment reached 3.86%and 3.17%.Poor venous drainage including sinus dynamic obstruction(21 cases,50.0%)and sinus occlusion(17 cases,40.48%)were found with high frequency among these ***,33 cases were cured(78.57%),and 4 cases faced surgery-related complications(9.52%).During 24-140 months’follow-up,the mean mRS score reduced to 0.57±***,only 22 cases(52.38%)recovered to absolutely normal,and poor venous drainage was the risk factor for patients’incomplete recovery(p=0.028,Exp(B)=14.692,95%CI 1.346 to 160.392).Compared with the older group,younger group showed more chronic symptoms,more secondary pathological changes,more times treatment and worse prognosis(p=0.013,0.002,0.000 and 0.032,respectively).Conclusions Pediatric PAVF has different angioarchitectures,clinical features and prognoses in different age *** venous drainage is an important factor leading to poor prognosis,and it accounts for incomplete recovery in nearly half of patients.

关键词： pediatric prognosis epilepsy

Addressable structured light system using metasurface optics and an individually addressable VCSEL array

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Photonics Research 2024年第6期12卷 1129-1137页

作者： CHENYANG WU XUANLUN HUANG YIPENG JI TINGyu CHENG jiaxing WANG NAN CHI SHAOHUA yu CONNIE J.CHANG-HASNAIN School of Information Science and Technology Fudan UniversityShanghai 200433China Berxel Photonics Co. Ltd.Shenzhen 518071China Peng Cheng Laboratory Shenzhen 518055China Chinese University of Hong Kong Shenzhen 518172China

Structured-light(SL)based 3D sensors have been widely used in many *** SL is the most widely deployed among all SL sensors due to its light weight,compact size,fast video rate,and low *** transmitter(known as the dot projector)consists of a randomly patterned vertical-cavity surface-emitting laser(VCSEL)array multiplicated by a diffractive optical element(DOE)with a fixed repeated *** that the separation of any two speckles is only one known and fixed number(albeit random),there are no other known scales to cal-ibrate or ***,typical SL sensors require extensive in-factory calibrations,and the depth resolution is limited to 1 mm at-60 cm *** this paper,to the best of our knowledge,we propose a novel dot projector and a new addressable SL(ASL)3D sensor by using a regularly spaced,individually addressable VCSEL array,multiplicated by a metasurface-DOE(MDOE)into a random pattern of the *** turning on or off the VCSELs in the array provides multiple known distances between neighboring speckles,which is used as a“built-in caliper”to achieve higher accuracy of *** as a precise“vernier caliper,”the addressable VCSEL array enables fine control over speckle positions and high detection *** experimentally dem-onstrated that the proposed method can result in sub-hundred-micron level *** new concept opens new possibilities for applications such as 3D computation,facial recognition,and wearable devices.

关键词： speckle light surface

Observing strain glass transition in Ti_(33)Nb_(15)Zr_(25)Hf_(25)O_(2)high entropy alloy with Elinvar effect

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第1期168卷 16-23页

作者： Kaichao Zhang Kai Wang Bin Wang Chao Lv jiaxing Zheng Guanqi Li yu Fu Wenlong Xiao Qingqing Cai Xutao Nie Yingfeng Shao Huilong Hou Xinqing Zhao School of Materials Science and Engineering Beihang UniversityBeijing 100191China China Aerodynamics Research and Development Center Mianyang 621000China State Key Laboratory of Nonlinear Mechanics Chinese Academy of SciencesInstitute of MechanicsBeijing 100190China Tianmushan Laboratory(Zhejiang Provincial Laboratory for Aviation) Hangzhou 310000China

Exploring the phase transition of high entropy alloys(HEAs)with multiple major elements is of great importance for understanding the underlying physical *** martensitic phase tran-sition has been frequently reported in HEAs,however,nanoscale microstructural phase evolution has not been investigated to the same ***,we have prepared the Ti_(33)Nb_(15)Zr_(25)Hf_(25)O_(2)HEA and investi-gated the strain glass transition and its associated properties using dynamic mechanical analysis and mi-crostructure *** have found that the elastic modulus in Ti_(33)Nb_(15)Zr_(25)Hf_(25)O_(2)HEA deviates from Wachtman’s equation and observed the Elinvar effect in the form of temperature-independent mod-ulus in the temperature range from 150 K to 450 K and frequency-dependence modulus around 220 *** strain glass transition has been evidenced in Ti_(33)Nb_(15)Zr_(25)Hf_(25)O_(2)HEA by the formation and growth of nano-sized domains during in-situ transmission electron microscopy(TEM)cooling,and substantiated by the broken ergodicity during zero-field-cooling/*** strain glass transition is believed to account for the Elinvar effect,where the modulus hardening of nano-sized domains compensates dynam-ically with the modulus softening of the transformable matrix.

关键词： High entropy alloys Strain glass transition Elinvar effect Microstructural evolution Nanodomains

考虑路径平滑性和避撞稳定性的智能汽车弯道轨迹规划研究

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

汽车工程 2022年第5期44卷 656-663页

作者：余嘉星 Arab Aliasghar 裴晓飞过学迅湖北省汽车零部件重点实验室武汉理工大学武汉430070 罗格斯大学机械与航空航天工程系美国新泽西皮斯卡塔韦08854

针对智能汽车弯道避障问题,提出了一种兼顾规划曲线平滑度和车辆稳定性的轨迹规划方法。将轨迹规划分为解耦的路径规划和速度规划处理,利用改进的快速随机搜索树(RRT)构建曲率连续且曲率变化量最小的无碰撞的螺旋线路径。改进后的RRT基... 详细信息

针对智能汽车弯道避障问题,提出了一种兼顾规划曲线平滑度和车辆稳定性的轨迹规划方法。将轨迹规划分为解耦的路径规划和速度规划处理,利用改进的快速随机搜索树(RRT)构建曲率连续且曲率变化量最小的无碰撞的螺旋线路径。改进后的RRT基于深度神经网络的度量函数,选取并连接代价函数最小的树节点,并通过搜索附近节点寻找是否存在代价函数更小的节点。而在速度规划中首先根据道路限速规则,采用梯形规划输出连续的目标加速度曲线。然后基于螺旋线路径曲率和自车状态,采用预瞄加速度矢量控制(PGVC)动态调整目标加速度,最后通过加速度控制逻辑获得最终的期望加速度。仿真结果表明,所提出的轨迹规划方法不仅能使智能汽车满足弯道避撞和路径跟踪的目标要求,且提高了车辆高速过弯的稳定性能,同时本文还验证RRT的快速收敛性质、路径平滑性和基于并行计算的实时性。

关键词：智能汽车轨迹规划快速随机搜索树速度规划弯道避撞

Ask Me Any Type:Type Inference Plugin for Partial Code on the Web and in the Integrated Development Environment

在线全文

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2024年第4期29卷 349-356页

作者： CHENG yu HUANG Guanming WU Yishun ZHAO Zijie HE Zhenhao LU jiaxing College of Computer and Information Engineering Jiangxi Normal UniversityNanchang 330022JiangxiChina The High School Attached to Jiangxi Normal University Nanchang 330013JiangxiChina

Inferring the fully qualified names(FQNs)of undeclared receiving objects and non-fully-qualified type names(non-FQNs)in partial code is critical for effectively searching,understanding,and reusing partial *** type inference tools,such as COSTER and SNR,rely on a symbolic knowledge base and adopt a dictionary-lookup strategy to map simple names of undeclared receiving objects and non-FQNs to ***,building a symbolic knowledge base requires parsing compilable code files,which limits the collection of APIs and code contexts,resulting in out-of-vocabulary(OOV)*** overcome the limitations of a symbolic knowledge base for FQN inference,we implemented Ask Me Any Type(AMAT),a type of inference plugin embedded in web browsers and integrated development environment(IDE).Unlike the dictionary-lookup strategy,AMAT uses a cloze-style fill-in-the-blank strategy for type *** treating code as text,AMAT leverages a fine-tuned large language model(LLM)as a neural knowledge base,thereby preventing the need for code *** results show that AMAT outperforms state-of-the-art tools such as COSTER and *** practice,developers can directly reuse partial code by inferring the FQNs of unresolved type names in real time.

关键词： type inference large language model prompt learning web and integrated development environment(IDE)plugin

在线全文

学校读者我要写书评

暂无评论

政府言行一致与企业股价崩盘风险

系统工程理论与实践 2024年第3期44卷 853-873页

作者：伍翕婷游家兴于明洋山东大学管理学院济南250100 厦门大学管理学院厦门361005

本文通过人工阅读各个城市政府工作报告构建各地政府言行一致指标,以2003–2018年我国A股非金融上市企业为样本,实证检验政府言行一致对股价崩盘风险的影响.研究发现,当地方政府言行一致程度越高时,当地企业股价崩盘风险越低.机制检验发... 详细信息

本文通过人工阅读各个城市政府工作报告构建各地政府言行一致指标,以2003–2018年我国A股非金融上市企业为样本,实证检验政府言行一致对股价崩盘风险的影响.研究发现,当地方政府言行一致程度越高时,当地企业股价崩盘风险越低.机制检验发现,随着地方政府言行一致程度的提高,不仅宏观层面展现出更强的群体规范和更高的法治水平,而且微观层面上地方企业的盈余质量越高、董事会报告的异常语调越低.异质性分析表明,政府言行一致对企业股价崩盘风险的抑制作用在不具有政治关系网络的企业中更加显著.本文研究表明,政府作为从事社会公共事务管理的权威性力量,其言行一致起到了十分重要的标杠作用,这对政府实现高质量发展目标具有积极的启示意义.

关键词：目标治理体制政府言行一致政府工作报告股价崩盘风险

Hollow Multishelled Structure: Synthesis Chemistry and Application

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2024年第3期40卷 346-393页

作者： MAO Dan WANG Chao LI Wei ZHOU Liang LIU Jian ZHENG Zjian ZHAO Yong CAO An-min WANG Shutao HUANG jiaxing HUO Fengwei CHEN Hongyu MAI Liqiang yu Ranbo WANG Lianzhou LU yunfeng yu Chengzhong YANG Qihua YANG Zhenzhong ZENG Hua Chun ZHAO Hujun TANG Zhiyong ZHAO Dongyuan WANG Dan State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChineseAcademy of SciencesBeijing 100190P.R.China Key Laboratory of Biopharmaceutical Preparation and Delivery Chinese Academy of SciencesBejing 100190P.R.China School of Fashion and Textiles The Hong Kong Polytechnic UniversityHong Kong SARP.R.China Department of Chemistry Fudan UniversityShanghai 200433P.R.China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070P.R.China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023P.R.China School of Chemistry Beihang UniversityBejing 100191P.R.China CAS Key Laboratory of Molecular Nanostructure and Nanotechnology and Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing 100190P.R.China CAS Key Laboratory of Bio-inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190P.R.China School of Engineering Westlake UniversityHangzhou 310024P.R.China School of Flexible Electronics(Future Technologies) Nanjing Tech UniversityNanjing 211816P.R.China School of Science Westlake UniversityHangzhou 310024P.R.China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070P.R.China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083P.R.China School of Chemical Engineering and Australian Institute for Bioengineering and Nanotechnology The University of QueenslandBrisbaneQueensland 4072Australia College of Life Science and Technology Bejing University of Chemical TechnologyBejing 100029P.R.China School of Chemistry and Molecular Engineering East China Normal UniversityShanghai 200241P.R.China College of Life Sciences Zhejiang Normal UniversityJinhua 321004P.R.China Department of Chemical Engineering Tsinghua UniversityBeijing 100

Hollow multishelled structure(HoMS),a promising and complex multifunctional structural system,features at least two shells that are separated by internal *** unique structure endows it with numerous advantages including low density,high loading capacity,large specific surface area,facilitated mass transport,and multiple spatial confinement *** the past twenty years,benefiting from the booming development of synthesis methods,various HoMS materials have been prepared and show promising applications in diverse areas.

关键词： Hollow multishelled structure Synthesis chemistry Energy storage Catalysis Electromagnetic wave absorption Drug delivery Sensor