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水利信息化建设程度量化评估探析

水利技术监督 2024年第6期 31-34,51页

作者：邱志伟朝阳县乌兰河硕蒙古族乡水利水保站辽宁朝阳122632

基于二元AHP模型,分别从信息化处理能力、基础建设水平、信息系统应用情况、管理信息化水平、信息采集与传输能力等5个层面,并选取沈阳、大连、鞍山、丹东4市作为典型区域,对各市水利信息化建设程度进行评估。结果表明,该方法可解决传... 详细信息

基于二元AHP模型,分别从信息化处理能力、基础建设水平、信息系统应用情况、管理信息化水平、信息采集与传输能力等5个层面,并选取沈阳、大连、鞍山、丹东4市作为典型区域,对各市水利信息化建设程度进行评估。结果表明,该方法可解决传统评估定性为主局限,通过评估,大连水利信息化建设程度综合评估值为0.45,达到良好等级,其他城市水利信息化建设程度为中等等级。成果对于水利信息化建设程度量化评估具有参考价值。

关键词：水利信息化建设程度量化评估二元AHP模型

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辽宁省中型灌区农业节水潜力改进方法研究

水利技术监督 2024年第7期 228-231页

作者：邱志伟朝阳县乌兰河硕蒙古族乡水利水保站辽宁朝阳122632

为提高辽宁地区中型灌区农业节水潜力,针对传统农业节水潜力计算方法求解局限,提出改进农业节水潜力估算方法,并选取辽宁省5座中型灌区进行实例应用。结果表明:计算方法改进后,各中型灌区农业节水潜力计算序列均方差可平均降低5.5%,计... 详细信息

为提高辽宁地区中型灌区农业节水潜力,针对传统农业节水潜力计算方法求解局限,提出改进农业节水潜力估算方法,并选取辽宁省5座中型灌区进行实例应用。结果表明:计算方法改进后,各中型灌区农业节水潜力计算序列均方差可平均降低5.5%,计算精度得到明显改善。通过评估,5座中型灌区在未来10年其农业节水潜力在0.625亿~0.745亿m 3之间,农业节水潜力较高。研究成果对于灌区农业节水潜力科学估算具有参考价值。

关键词：农业节水潜力中型灌区改进方法辽宁省

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太子河流域典型中小河流萎缩程度定量评估

水利技术监督 2024年第8期 45-49页

作者：邱志伟朝阳县乌兰河硕蒙古族乡水利水保站辽宁朝阳122632

为提高中小河流治理工程设计的合理性,建立河流萎缩度评估模型,文章选取太子河流域4条典型中小河流为研究实例,对各中小小河流萎缩度进行定量评估。结果表明:建立的河流萎缩度评估模型可综合考虑河流形态、水文特征、水生态等指标,对于... 详细信息

为提高中小河流治理工程设计的合理性,建立河流萎缩度评估模型,文章选取太子河流域4条典型中小河流为研究实例,对各中小小河流萎缩度进行定量评估。结果表明:建立的河流萎缩度评估模型可综合考虑河流形态、水文特征、水生态等指标,对于河流萎缩度评估结果总体合理。通过评估,太子河流域4条典型中小河流萎缩度在-0.059~-0.0509之间,总体处于基本稳定-中等萎缩状态。研究成果对于中小河流萎缩度综合定量评估具有参考价值。

关键词：河流萎缩度综合评估模型中小河流太子河流域

热处理工艺对SLM打印成形CoCrMoW显微结构和力学性能的影响

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材料研究与应用 2024年第5期18卷 769-776页

作者：邱芷薇广州纳联材料科技有限公司广东广州510651 江西悦安新材料股份有限公司江西赣州341500

CoCrMoW合金是烤瓷牙金属基底和可拆卸活动支架的理想材料。针对SLM成形CoCrMoW合金的热处理工艺,尤其是较长的时效时间导致的生产效率过低,以及热处理后SLM成形件尺寸一致性和翘曲变形程度等问题,对热处理后的合金性能进行了研究。以... 详细信息

CoCrMoW合金是烤瓷牙金属基底和可拆卸活动支架的理想材料。针对SLM成形CoCrMoW合金的热处理工艺,尤其是较长的时效时间导致的生产效率过低,以及热处理后SLM成形件尺寸一致性和翘曲变形程度等问题,对热处理后的合金性能进行了研究。以气雾化CoCrMoW合金粉末(粒度15—53μm)为原材料,采用SLM方法打印CoCrMoW合金试样,并将其分别在920、960和1000℃下进行热处理并保温1 h,随炉冷却至600℃后取出。采用SEM、EDS和拉伸测试等方法,研究热处理工艺对SLM打印态CoCrMoW合金的显微结构及力学性能的影响。结果表明:热处理后合金基体的晶内、晶界均析出了第二相颗粒,在温度920和960℃下析出相颗粒分布均匀且密集,而在温度1000℃下晶内部分析出相溶解;随着热处理温度的提高,析出相明显生长得更加粗大。根据EDS成分分析,判断析出相为金属间化合物Co_(3)(Mo,W)_(2)Si。不同热处理条件下,试样的力学性能有明显差异,并且与析出相的分布、数量、尺寸密切相关。当在920℃下进行热处理时,密集细小的析出相对基体的强化效果最为显著,表现为最高的屈服强度(1134 MPa)、最低的塑性(延伸率7%),断口为脆性倾向的准解理断裂。随着热处理温度升高,析出相发生了粗化且部分溶解,试样的强度逐渐下降,而塑性逐渐提升。在1000℃下进行热处理时,合金的力学性能恢复至接近打印态水平,屈服强度892 MPa、延伸率14.8%,断口为韧性倾向的准解理断裂,此时合金兼具高强度和高塑韧性。此外,较高的热处理温度可以更有效地释放残余应力,减小翘曲变形,经1000℃热处理后的试样形变量最小(0.13 mm)。热处理条件对SLM成形CoCrMoW合金的性能和形变控制至关重要,可以根据不同应用需求进行选择。

关键词： CoCrMoW合金齿科材料激光选区熔化热处理显微结构力学性能翘曲变形残余应力

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盾构机管片拼装微调机构动力学分析

同济大学学报（自然科学版） 2024年第6期52卷 953-961页

作者：王道智闵锐袁向华李万莉邱志伟王秋平同济大学机械与能源工程学院上海201804 上海城建隧道装备有限公司上海200137

为了研究拼管作业时盾构机管片拼装微调机构驱动油缸的推力,分析了微调机构在偏转和俯仰运动下的动力学特性。首先,对简化的管片拼装微调机构平台角度与驱动油缸行程的关系进行研究,并利用Matlab Simscape模块对机构进行建模仿真,得到... 详细信息

为了研究拼管作业时盾构机管片拼装微调机构驱动油缸的推力,分析了微调机构在偏转和俯仰运动下的动力学特性。首先,对简化的管片拼装微调机构平台角度与驱动油缸行程的关系进行研究,并利用Matlab Simscape模块对机构进行建模仿真,得到指定运动轨迹下2个驱动油缸的驱动力;接着,利用ADAMS(automatic dynamic analysis of mechanical systems)对机构进行动力学仿真,验证所搭建模型的正确性;最后,利用ADAMS对机构进行带载工况下的动力学仿真,得到2个油缸的最大推力。结果表明,管片拼装微调机构在以幅值为0.035 rad、角频率为1 rad·s-1的正弦函数进行俯仰和偏转运动时2个油缸的最大推力分别为8998.47 N和6390.48 N。

关键词：盾构机管片拼装机并联机构动力学模型

Segments-based progressive TIN densification filter for DTM generation from airborne LIDAR data

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High Technology Letters 2017年第1期23卷 16-22页

作者：许颖 qiu zhiwei Yue Dongjie Ministry of Water Resources Key Laboratory for the Process and Control of Soil and Water Loss in Loess Plateau School of Earth Sciences and Engineering Hohai University

Airborne light detection and ranging( LIDAR) has revolutionized conventional methods for digital terrain models( DTMs) acquisition. Ground filtering for airborne LIDAR is one of the core steps taken to obtain a high quality DTM. This paper presents a segments-based progressive TIN( triangulated irregular network) densification( SPTD) filter that can automatically separate ground points from non-ground points. The SPTD method is composed of two key steps: point cloud segmentation and clustering by iterative judgement. The clustering method uses the dual distance to obtain a set of seed points as a coarse spatial clustering process. Then the rest of the valid point clouds are classified iteratively. Finally,the datasets provided by ISPRS are utilized to test the filtering *** comparison with the commercial software Terra Solid,the experimental results show that the SPTD method in this paper can avoid single threshold restrictions. The expected accuracy of ground point determination is capable of producing reliable DTMs in the discontinuous areas.

关键词： airborne light detection and ranging (LIDAR) point cloud ground filtering tri-angulated irregular network (TIN) digital terrain models (DTMs)

Investigation of Surface-inset Machines with Mixed Grade Magnets Considering Magnet Thickness

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CES Transactions on Electrical Machines and Systems 2022年第3期6卷 252-260页

作者： Youyuan Ni Liang Zhang zhiwei qiu the School of Electrical Engineering&Automation Hefei University of TechnologyHefei230009China

This paper presents a mixed grade magnet model for surface-inset machines considering the magnet thickness. In the polar coordinates, on the basis of the Laplace/quasi-Poisson equations and boundary conditions, the constructed matrix equations are solved and the air gap magnetic field in the machine is derived. Taking an 8-pole/12-slot surface-inset motor as an example, through the presented optimization process, the air gap field is optimized considering the magnet thickness, remanence and magnetization angle. In addition, the back-EMF and electromagnetic torque are analytically obtained. The optimized results show that the proposed mixed grade magnet model has larger electromagnetic torque and smaller torque ripple than the conventional one. Finally, the analytical predictions are evaluated by finite element analysis(FEA).

关键词： Mixed grade magnet Surface-inset machines Magnet thickness Remanence Torque ripple

Highly sensitive colorimetric detection of NH3 based on Au@Ag@AgCl core-shell nanoparticles

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Chinese Chemical Letters 2021年第9期32卷 2807-2811页

作者： zhiwei qiu Yitong Xue Jiyong Li Yunzhi Zhang Xinyi Liang Congying Wen Houjian Gong Jingbin Zeng College of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China College of Science China University of Petroleum(East China)Qingdao 266580China Petroleum Engineering Technology Research Institute Sinopec Shengli Oilfield CompanyDongying 257067China

Abstract:As an important component of the atmosphere,ammonia(NH_(3))plays a very important role in maintaining the balance of ***,it is also one of the most toxic gases that can cause damage to the human respiratory system and mucous membranes even at low *** such,development of highly sensitive and selective NH_(3)sensors is of high significance for environmental monitoring and health ***,we have synthesized Au@Ag@Ag Cl core-shell nanoparticles(NPs)by oxidative etching and precipitating Au@Ag core-shell NPs using FeCl3 and further used them as optical probes for the colorimetric detection of NH_(3).The sensing mechanism is based on the fact that the etching of NH_(3)on AgCl and Ag shell leads to the variations of ingredients and core-to-shell ratio of the Au@Ag@AgCl NPs,thereby inducing noticeable spectral and color *** replacing the outmost layer of Ag with AgCl,not only is the stability of the sensor against oxygen significantly enhanced,but also is the sensitivity of the method *** method exhibits good linear relationship for the detection of NH_(3)from 0 to 5000 mmol/L with the limit of detection of 6.4 mmol/*** method was successfully applied to the detection of simulated air polluted by NH_(3),indicating its practical applicability for environmental *** method shows great potential for on-site NH_(3)detection particularly in remote area,where a simple,fast,low-cost,and easy-to-handle method is highly desirable.

关键词： NH3 detection Au@Ag@AgCl nanoparticles Localized surface plasmon resonance Etching Colorimetric sensor

Targeting integrin pathways:mechanisms and advances in therapy

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Signal Transduction and Targeted Therapy 2023年第2期8卷 381-422页

作者： Xiaocong Pang Xu He zhiwei qiu Hanxu Zhang Ran Xie Zhiyan Liu Yanlun Gu Nan Zhao Qian Xiang Yimin Cui Department of Pharmacy Peking University First HospitalXishiku StreetXicheng District100034BeijingChina Institute of Clinical Pharmacology Peking University First HospitalXueyuan Road 38Haidian District100191BeijingChina

Integrins are considered the main cell-adhesion transmembrane receptors that play multifaceted roles as extracellular matrix(ECM)-cytoskeletal linkers and transducers in biochemical and mechanical signals between cells and their environment in a wide range of states in health and *** functions are dependable on a delicate balance between active and inactive status via multiple mechanisms,including protein-protein interactions,conformational changes,and *** to their exposure on the cell surface and sensitivity to the molecular blockade,integrins have been investigated as pharmacological targets for nearly 40 years,but given the complexity of integrins and sometimes opposite characteristics,targeting integrin therapeutics has been a *** date,only seven drugs targeting integrins have been successfully marketed,including abciximab,eptifibatide,tirofiban,natalizumab,vedolizumab,lifitegrast,and ***,there are approximately 90 kinds of integrin-based therapeutic drugs or imaging agents in clinical studies,including small molecules,antibodies,synthetic mimic peptides,antibody-drug conjugates(ADCs),chimeric antigen receptor(CAR)T-cell therapy,imaging agents,etc.A serious lesson from past integrin drug discovery and research efforts is that successes rely on both a deep understanding of integrin-regulatory mechanisms and unmet clinical ***,we provide a systematic and complete review of all integrin family members and integrin-mediated downstream signal transduction to highlight ongoing efforts to develop new therapies/diagnoses from bench to *** addition,we further discuss the trend of drug development,how to improve the success rate of clinical trials targeting integrin therapies,and the key points for clinical research,basic research,and translational research.

关键词： drugs mechanisms inactive