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三维激光扫描仪在排水管网测量中的应用

中国给水排水 2024年第2期40卷 99-105页

作者：崔家武李海军曾波甄兆聪广州市城市规划勘测设计研究院有限公司广东广州510060

随着城市地下管线信息化管理、表达和应用从二维向三维延伸,可利用三维激光扫描及点云建模技术开展三维管网建设工作。以某排水管网为研究案例,采用架站式激光扫描仪和移动式激光扫描仪对排水管网进行扫描,主要介绍了两种扫描方式的技... 详细信息

随着城市地下管线信息化管理、表达和应用从二维向三维延伸,可利用三维激光扫描及点云建模技术开展三维管网建设工作。以某排水管网为研究案例,采用架站式激光扫描仪和移动式激光扫描仪对排水管网进行扫描,主要介绍了两种扫描方式的技术要点及优缺点,最后对管网扫描精度进行了分析。结果表明,采用三维激光扫描仪测量排水管网,可以解决传统二维管线空间关系不明晰、显示效果不直观等问题,此次研究可为未来大规模开展管网激光扫描工作提供经验。

关键词：排水管网架站式激光扫描移动式激光扫描点云

BLADE SECTION DESIGN OF MARINE PROPELLERS WITH MAXIMUM CAVITATION INCEPTION SPEED

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Journal of Hydrodynamics 2012年第1期24卷 65-75页

作者： zeng Zhi-bo KUIPER Gert China Ship Scientific Research Center Wuxi 214082China Soetendaalseweg 106721 XB BennekomThe Netherlands

Kuiper and Jessup（1993）developed a design method for propellers in a wake based on the Eppler foil design *** optimized section is transformed into the three-dimensional propeller flow using the approach of the effective blade *** blade sections are two-dimensional sections in two-dimensional flow which have the same chordwise loading distribution as the three-dimensional blade sections of a ***,the design procedure is laborious in two aspects：finding an optimum blade section using the Eppler program requires much skill of the designer,and transforming the two-dimensional blade section into a propeller blade section in three-dimensional flow is *** this work,these two problems were coped with.A blade section design procedure was presented using an optimization technique and an alternative procedure for the effective blade section is developed using a lifting surface design *** validate the method a benchmark model of a naval ship was *** benchmark model was extended by new appendices and a reference propeller,and designed using conventional design *** reference propeller was optimized using the new design procedure and model tests were carried *** attention was given to the data of the model and the reference propeller,to make the configuration suitable for the Reynolds-Averaged Navier-Stokes（RANS）calculations.

关键词： blade section Eppler foil design method genetic algorithm cavitation inception high speed cavitation observation

考虑气水两相流动的页岩气井压裂-生产一体化数值模拟

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石油勘探与开发 2024年第3期51卷 597-607页

作者：唐慧莹罗山贵梁海鹏曾波张烈辉赵玉龙宋毅西南石油大学油气藏地质及开发工程全国重点实验室成都610500 成都理工大学成都610059 中国石油西南油气田公司页岩气研究院成都610051

基于位移不连续法和离散裂缝统一管网模型,采用顺序迭代数值模拟方法,构建了考虑气水两相流动的页岩气井压裂-生产一体化数值模型。模型考虑了天然裂缝、基质物性对压裂过程的影响,且直接将压裂后地层压力及含水饱和度分布用于后续焖井... 详细信息

基于位移不连续法和离散裂缝统一管网模型,采用顺序迭代数值模拟方法,构建了考虑气水两相流动的页岩气井压裂-生产一体化数值模型。模型考虑了天然裂缝、基质物性对压裂过程的影响,且直接将压裂后地层压力及含水饱和度分布用于后续焖井、生产模拟,可以更准确地实现压裂-生产一体化模拟。模拟结果表明:储层物性参数对裂缝扩展有较大影响,合理预测压裂结束后地层压力及储层流体分布是准确预测页岩气井产气量、产液量的关键;相较于常规方法,提出的模型同时考虑压裂对基质压力及含水饱和度的影响,可以更准确地模拟产水量、产气量。将建立的模型应用于实际页岩气压裂水平井的压裂-生产一体化模拟,模拟结果与实际生产数据吻合程度较好,验证了模型的准确性。

关键词：页岩气井水力压裂压裂缝网扩展气水两相流动压裂-生产一体化数值模拟

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高粱两步法厌氧发酵产己酸研究

食品科学技术学报 2024年第1期42卷 164-176页

作者：邓星成任志强曾波卫春会邓杰谢军黄治国四川轻化工大学酿酒生物技术及应用四川省重点实验室四川宜宾644000 中国轻工业酿酒生物技术及智能制造重点实验室四川宜宾644000

研究以富含淀粉的高粱为原料,通过两步法厌氧发酵提高己酸生成效率,即第一步分别接种己酸复合菌液、接种嗜酸乳杆菌TYCA06、添加酿酒酵母制得丁酸发酵液、乳酸发酵液、乙醇发酵液,第二步将丁酸发酵液、乳酸发酵液、乙醇发酵液等3种发酵... 详细信息

研究以富含淀粉的高粱为原料,通过两步法厌氧发酵提高己酸生成效率,即第一步分别接种己酸复合菌液、接种嗜酸乳杆菌TYCA06、添加酿酒酵母制得丁酸发酵液、乳酸发酵液、乙醇发酵液,第二步将丁酸发酵液、乳酸发酵液、乙醇发酵液等3种发酵液混合,并接种己酸复合菌液,厌氧发酵制得己酸。研究发现:通过优化丁酸发酵液、乳酸发酵液、乙醇发酵液的发酵工艺,丁酸发酵液中的丁酸、乙酸产量达到20.16 g/L和8.47 g/L,淀粉转化率达到76.02%;乳酸发酵液中的乳酸产量和乳酸产率分别达到11.41 g/L和42.48%;乙醇发酵液中的乙醇产率可达95.06%。继续优化己酸发酵工艺,发现当乙醇发酵液和乳酸发酵液同时作为电子供体时,己酸产量和产率均显著提升,分别达到4.15 g/L和75.2 mg/g,且当乙醇发酵液和乳酸发酵液中乙醇与乳酸添加的质量浓度比为2∶1时,己酸产量和产率均达到最高,分别为6.65 g/L和99.78 mg/g。对己酸发酵过程中微生物与己酸的相关性分析发现,发酵过程中和己酸含量呈正相关的微生物有产己酸菌属(Caproiciproducens)、Clostridium_sensu_stricto_12、Pseudoclavibacter。其中Caproiciproducens随着发酵进行不断富集,到发酵后期相对丰度达到37.81%,是己酸形成的主要贡献者。希望研究可为无外源电子供体添加条件下,实现高粱两步法厌氧发酵生产己酸提供理论基础,为拓展高粱的资源化利用提供思路。

关键词：高粱两步法厌氧发酵己酸微生物群落产己酸菌属

Prediction model of interval grey number based on DGM(1,1)

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Journal of Systems Engineering and Electronics 2010年第4期21卷 598-603页

作者： bo zeng Sifeng Liu Naiming Xie College of Business Planning Chongqing Technology and Business University Chongqing 400067 E R. China College of Economics and Management Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China

In grey system theory,the studies in the field of grey prediction model are focused on real number sequences,rather than grey number ***,a prediction model based on interval grey number sequences is *** mining the geometric features of interval grey number sequences on a two-dimensional surface,all the interval grey numbers are converted into real numbers by means of certain algorithm,and then the prediction model is established based on those real number *** entire process avoids the algebraic operations of grey number,and the prediction problem of interval grey number is usefully ***,through an example＇s program simulation,the validity and practicability of this novel model are verified.

关键词： grey system theory prediction model interval grey number grey number band grey number layer DGM(1 1) model.

再生砂品质与取代率对混凝土附加用水量及力学性能影响研究

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水利水电技术（中英文） 2024年第8期55卷 152-160页

作者：金德川李北星陈鹏博曾波武汉理工大学硅酸盐建筑材料国家重点实验室湖北武汉430070 北京都市绿源环保科技有限公司固废研发中心北京102601

【目的】附加用水是再生混凝土中为补偿再生骨料吸水而额外添加的水分,其用量对混凝土性能有重要影响。为了探究再生砂品质与取代率对再生混凝土附加用水量取值和基本力学性能的影响,【方法】通过调节附加用水量使再生混凝土拌和物具有... 详细信息

【目的】附加用水是再生混凝土中为补偿再生骨料吸水而额外添加的水分,其用量对混凝土性能有重要影响。为了探究再生砂品质与取代率对再生混凝土附加用水量取值和基本力学性能的影响,【方法】通过调节附加用水量使再生混凝土拌和物具有相近的工作性能,对比研究了Ⅰ类、Ⅱ类和Ⅲ类三种品质再生砂以30%、50%、70%质量分数取代天然砂制备的再生混凝土的附加用水量和力学性能。【结果】结果表明,附加用水量随着再生砂取代率的增大而线性增大,附加用水量和附加用水量补偿系数随再生砂品质的降低而增大,Ⅰ类、Ⅱ类和Ⅲ类再生砂附加用水量补偿系数分别为0.62、0.84和0.96;随着再生砂品质降低或取代率的增大,再生混凝土抗压强度、抗折强度、弹性模量不断降低,再生砂品质与取代率对抗折强度影响最大;降低再生砂品质或提高再生砂取代率总体上使混凝土的折压比减小,即脆性增加。【结论】由此可认为,再生混凝土的附加用水量补偿系数应根据再生砂的品质高低而调整取值:低品质再生砂宜取较高的附加用水量补偿系数值,高品质再生砂可适当降低附加水用量补偿系数;再生砂的掺入增大了再生混凝土的脆性,当再生混凝土作为以抗弯为主的受力构件时需降低再生砂取代率或采用高品质再生砂。

关键词：再生砂品质混凝土附加用水量力学性能强度

正交异性钢桥面板疲劳裂纹图像巡检测量系统研究

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公路 2024年第9期69卷 343-350页

作者：周焕新程斌黄斌曾令博滕念管上海交通大学船舶海洋与建筑工程学院上海市200240

为提高正交异性钢桥面板疲劳裂纹检测效率及精度,研究提出了一套集磁吸附攀爬机器人与裂纹图像处理平台为一体的新型巡检测量系统。攀爬机器人所搭载的磁吸附装置使其能安全吸附在顶板、U肋侧板以及横隔板表面,并按预先设定路线或手动... 详细信息

为提高正交异性钢桥面板疲劳裂纹检测效率及精度,研究提出了一套集磁吸附攀爬机器人与裂纹图像处理平台为一体的新型巡检测量系统。攀爬机器人所搭载的磁吸附装置使其能安全吸附在顶板、U肋侧板以及横隔板表面,并按预先设定路线或手动操作路线开展裂纹图像巡检工作,裂纹采集平台通过Wi-Fi远程控制工业相机与激光测距自标定装置,采集并实时回传图片及标定数据以计算相机的内参和外参。后处理阶段,裂纹处理平台基于神经网络训练和单应性矩阵计算,完成裂纹图像识别以及裂纹几何特征提取,并借助图像拼接技术生成钢桥面板疲劳裂纹分布全景图。在正交异性钢桥面板足尺模型上应用该系统进行裂纹图像采集与测量,结果表明:各区域常见疲劳裂纹均可实现无障碍测量,标尺长度的测量误差均在0.2%以内,平均误差仅为0.14%,裂纹分辨能力达到亚毫米级。研发的疲劳裂纹图像巡检测量系统具备很高的测量精度,且与传统方法相比具有检测过程自动高效、检测区域全覆盖等显著优势,可在实际桥梁工程中推广应用。

关键词：桥梁检测正交异性钢桥面板疲劳裂纹巡检系统图像测量攀爬机器人

Self-healing Hydrogelsand Underlying Reversible Intermolecular Interactions

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Chinese Journal of Polymer Science 2021年第10期39卷 1246-1261,I0005页

作者： Meng Wu Qiong-Yao Peng Lin-bo Han Hong-bo zeng Department of Chemical&Materials Engineering University of AlbertaEdmontonAlberta T6G 1H9Canada College of Health Science and Environmental Engineering Shenzhen Technology UniversityShenzhen 518118China

Self-healing hydrogels have attracted growing attention over the past decade due to their biomimetic structure,biocompatibility,as well as enhanced lifespan and reliability,thereby have been widely used in various biomedical,electrical and environmental engineering *** feature article has reviewed our recent progress in self-healing hydrogels derived from mussel-inspired interactions,multiple hydrogen-bonding functional groups such as 2-ureido-4[1H]-pyrimidinohe(UPy),dynamic covalent bonds(eg,Schiff base reactions and boronic ester bonds).The underlying molecular basics of these interactions,hydrogel preparation principles,and corresponding performances and applications are *** underlying reversible intermolecular interaction mechanisms in these hydrogels were investigated using nanomechanical techniques such as surface forces apparatus(SFA)and atomic force microscopy(AFM),providing fundamental insights into the self-healing mechanisms of the *** remaining challenging issues and perspectives in this rapidly developing research area are also discussed.

关键词： Self-healing hydrogels Mussel-inspired Interaction Multiple hydrogen-bonding Dynamic covalent bonds Intermolecular forces

body attributes of both parents jointly affect offspring sex allocation in a socially monogamous, size-monomorphic passerine

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Current Zoology 2013年第2期59卷 271-277页

作者： Xin LU Xianhai zeng bo DU Department of Zoology College of Life Sciences Wtthan University Wuhan 430072 China

Theory predicts that because males are more variable in reproductive success than females, a mother should produce more sons to maximize fitness return from the sex allocation if she is of high-quality （the female quality hypothesis） or mates with a high-quality male （the male quality hypothesis）. While most previous studies have looked at each hypothesis, we tested both of them simultaneously in the white-rumped snowfinch Montifringilla taczanowskii, a socially monogamous, sexually monomorphic passerine where body size is a potential indicator of individual quality in intrasexual competition and territory de- fense. Brood sex ratios at the population level did not deviate from random expectation. Among individual broods, the proportion of sons did not depend on body size of either male or female parent, but on interaction of this trait of both parents. Further analy- ：~es revealed that brood sex ratios were independent of body size of male or female parents when their mates were smaller, but positively related with body size of male or female parents when their mates were larger. These results suggest that mechanisms underlying the two hypotheses may act jointly on offspring sex allocation. The mechanisms are expected to evolve through size-assortative mating which is often reached by sexual selection [Current Zoology 59 （2）： 271-277, 2013].

关键词： Brood sex ratio Parental quality Size-assortative mating White-rumped snowfinch