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Effects of Velocity-slip on the Flow and Heat Transfer of a Two- Dimensional Stagnation-point Flow Towards a Porous Stretching Sheet with Heat Generation/absorption

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Effects of Velocity-slip on the Flow and Heat Transfer of a ...

作者： soomro Feroz ahmed（苏莫）南京大学

学位级别：硕士

本文研究了作用在流上的两种速度滑移线(一阶速度滑移线及二阶速度滑移线)效应以及作用在不同可延展表面上二维滞点流的热传输效应。针对该问题的研究在工程应用领域具有重要意义,并已成为近期的热门研究方向。本文工作可分为四个部分... 详细信息

本文研究了作用在流上的两种速度滑移线(一阶速度滑移线及二阶速度滑移线)效应以及作用在不同可延展表面上二维滞点流的热传输效应。针对该问题的研究在工程应用领域具有重要意义,并已成为近期的热门研究方向。本文工作可分为四个部分。其中,第一部分用于介绍背景知识以及已有的基础研究文献。在第二部分,我们引入了描述该问题的数学模型,根据速度滑移线以及延展表面类型的不同,可将该问题分为三种场景。第三部则介绍离散方法及数值求解过程。数值结论和相关细节讨论在放在第四部分。本文引用的所有文献则见于文章末尾的附录部分。

关键词：可伸展板多孔介质相似变化打靶法部分滑移

基于SBAS-InSAR技术的巨野煤田沉降监测

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高技术通讯 2021年第3期31卷 333-340页

作者： Irfan ahmed soomro 范宇宾郭唯娜柯长青南京大学地理与海洋科学学院南京210023

矿产资源过度开采极易诱发地面塌陷等地质灾害,对矿区的生产生活造成了严重的威胁。采用2017年5月至2018年11月21景Sentinel-1A数据,设置时间基线(365 d)和空间基线(2371 m)并生成连接图,采用小基线集技术(SBAS)对生成的影像对进行干涉... 详细信息

矿产资源过度开采极易诱发地面塌陷等地质灾害,对矿区的生产生活造成了严重的威胁。采用2017年5月至2018年11月21景Sentinel-1A数据,设置时间基线(365 d)和空间基线(2371 m)并生成连接图,采用小基线集技术(SBAS)对生成的影像对进行干涉处理,通过生成的干涉相位进行地面沉降的参数反演,获取了巨野煤田的形变场和监测点的形变序列。结果发现,巨野煤田发生24 mm以上地面沉降的区域面积占比高达87.12%,而郭屯矿区的地面沉降最为严重,中心沉降量超过70 mm,年沉降速率达到45mm/a。巨野煤田的地面沉降由自然和人为因素造成,其中人为煤炭开采和地下水的过量使用是主要原因。与水准测量的对比结果表明,二者沉降监测的总体趋势吻合。该项研究工作表明,小基线集雷达干涉测量(SBAS-InSAR)技术可以很好地应用于矿区沉降的监测,为合理开采矿产资源和矿区环境保护提供参考依据。

关键词：小基线集雷达干涉测量(SBAS-InSAR) 煤炭开采矿区沉降巨野煤田

Efficacy of Watercourse Lining in Sindh —A Review Study in Relation with Kohistan Region

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Agricultural Sciences 2018年第9期9卷 1215-1227页

作者： Asadullah soomro Abdul Latif Qureshi Nisar ahmed Memon Zia uddin Abro US-Pakistan Center for Advanced Studies in Water (USPCAS-W) Mehran University of Engineering and Technology (MUET) Jamshoro Pakistan Water Sector Improvement Program Sindh Karachi Pakistan

The total number of watercourses in Pakistan is about 110,000 and particularly in Sindh it is about 46,699, out of which 7576 have been lined from 1977 to 1998 and from 2004 to 2015;22,479 have been lined and the remaining 16,644 still require improvement. At the current rate of progress, the lining of remaining watercourses would further take about 21 years. As designed life of the improved watercourse is about 25 years. By the time of ending of many watercourse improvement programs, there will again require the rehabilitation on many of the earlier watercourse lining schemes. Generally two types of watercourse lining are practiced in Sindh i.e. Rectangular Lined Watercourses (with single and double brick walls) and Trapezoidal Concrete Lined Watercourses. Because of efficient, effectiveness, easy maintenance and repair work, the Rectangular Lined Watercourse is more frequently practiced in Sindh. It is now suggested that: to renovate the watercourses an accelerated program should be started and the system (with the sense of terms and conditions) for renovation of watercourses program should also be changed. The research work towards different types of lining materials for watercourse should be conducted. Looking to the brief review it is suggested that a fiber glass type plastic material with semi-circular or U-shaped, pre-cast fabricated RCC Trapezoidal or Parabolic in place of brick mortar and concrete could be used for watercourse lining. This methodology, proposed to be used, will enable us to determine cost-benefit ratio, life span and such other parameters for its feasibility under variable climatic conditions of Sindh (North Sindh being dry and hot, while South Sindh semi-humid and warm).

关键词： Watercourse Lining Water Management in Pakistan

Ougenioxylon chinjiensis sp. nov., a New Fossil Species of the Family Leguminosae from Chinji Formation Salt Range, Punjab Pakistan

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American Journal of Plant Sciences 2014年第26期5卷 3745-3751页

作者： Noor-Ul-Ain soomro Basir ahmed Arain Muhammad Tahir Mehmood Rajput Institute of Plant Sciences University of Sindh Jamshoro Pakistan

This work is comprised of anatomical study of fossil wood collected from Chnji formation (72°22'E, 32°41'N) of Miocene age exposed at Chinji National Reservoir. The material consists of a single piece of petrified wood dark brown in colour. The three dimensional sections were prepared by ground thin section technique. Microscopic examination of the characters was compared with modern and fossil wood and found comparable with the family Leguminosae. The closest resemblance of our fossil wood is with the wood of Ougenia. This fossil wood shows close resemblance in respect of vessels, fibers, parenchyma and xylem rays character. Therefore it is considered as new species and it is named Ougenioxylon chienjiensis sp. nov. The specific epithet refers to Chinji formation to which fossil wood belongs.

关键词： Ougenia chinjiensis Fossil Wood Salt Range Punjab Pakistan

不同等级新疆骏枣物理特征及其对分级结果的影响

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农业机械学报 2018年第8期49卷 324-330页

作者：吴明清李传峰罗华平弋晓康 SHAKEEL ahmed soomro 陈坤杰南京农业大学工学院南京210031 塔里木大学机械电气化工程学院阿拉尔843300

为了给红枣分级参数的选择及定量分级标准的制定提供科学依据,对新疆所产骏枣的主要特征参数进行测量和统计分析,研究了红枣各特征参数之间的相关性和各特征参数随等级的变化规律。通过聚类的方法,将红枣的8个特征参数分为5个类型,对根... 详细信息

为了给红枣分级参数的选择及定量分级标准的制定提供科学依据,对新疆所产骏枣的主要特征参数进行测量和统计分析,研究了红枣各特征参数之间的相关性和各特征参数随等级的变化规律。通过聚类的方法,将红枣的8个特征参数分为5个类型,对根据不同特征参数进行分级所产生的参数误差进行了分析计算。试验结果显示,除密度外,红枣的各特征参数均对等级有显著影响,等级随特征参数标准偏差的减小而增大,各特征参数与等级之间存在显著的线性关系。各特征参数之间存在不同程度的相关性,轮廓面积和轮廓周长之间相关性最高,其次是轮廓周长和长度,除密度和质量、短径呈正相关外,密度和其他参数呈负相关。不同等级特征参数的平均误分率越高,分级效果越差;平均误分率越低,分级效果越好。密度的平均误分率最大,周长误分率最小。

关键词：红枣特征参数分级相关性分析

利用双向回交导入系定位水稻苗期耐亚铁毒和锌毒的QTL

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作物学报 2013年第10期39卷 1754-1765页

作者：张建 Aijaz ahmed soomro 柴路崔彦茹王小倩郑天清徐建龙黎志康中国农业科学院作物科学研究所/农作物基因资源与基因改良国家重大科学工程北京100081

铁和锌是水稻生长必需的微量元素,但在低洼或酸性土壤中,过量的二价铁和锌对水稻生长具毒害作用,最终造成生物量和产量下降。为探讨水稻苗期耐亚铁毒、锌毒的遗传机制,利用优质粳稻品种Lemont和高产籼稻品种特青为亲本构建的高代双向回... 详细信息

铁和锌是水稻生长必需的微量元素,但在低洼或酸性土壤中,过量的二价铁和锌对水稻生长具毒害作用,最终造成生物量和产量下降。为探讨水稻苗期耐亚铁毒、锌毒的遗传机制,利用优质粳稻品种Lemont和高产籼稻品种特青为亲本构建的高代双向回交导入系和308个在染色体上均匀分布的SNP标记剖析耐亚铁毒、锌毒相关的QTL。从双向导入系共检测到42个影响耐亚铁毒、锌毒相关性状如苗高、苗干重、根干重以及胁迫与对照相对值的QTL,多数位点增强亚铁毒、锌毒抗性的有利等位基因来自Lemont。其中同时在2个背景下表达的QTL有4个,占定位QTL总数的9.52%,说明大多数QTL的表达具有明显的遗传背景效应。同一遗传背景下同时影响耐亚铁毒和锌毒的QTL有9个,其中QSdw5在2个背景中均被检测到,其效应大小和方向一致,说明水稻苗期耐亚铁毒、锌毒之间存在遗传重叠位点。因此,通过分子标记辅助选择从Lemont中导入或聚合有利的遗传重叠区域,可以提高特青对亚铁毒、锌毒的抗性水平。

关键词：耐亚铁毒害耐锌毒害 QTL SNP 水稻

环氧树脂模填加剂模压处理后对MOS场效应晶体管引线键合可靠性的影响(英文)

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电子工业专用设备 2007年第12期36卷 19-25,31页

作者： Rohit T. Nayak toufique ahmed Arvind Krishna Ken Hollis Delphi Technical Center India 4th Floor Innovator ITPL Bangalore-560 066 India

氧化硅填充环氧树脂在作为芯片封装的密封中对微电子器件的可靠性与功能起着一种主要影响。在帮助了解铝引线键合内部类似功率MOS场效应晶体管的一种含铅电子组件的可靠性,在热力学机械特性试验结果表明由于栅离层的焊线接近引线框架,... 详细信息

氧化硅填充环氧树脂在作为芯片封装的密封中对微电子器件的可靠性与功能起着一种主要影响。在帮助了解铝引线键合内部类似功率MOS场效应晶体管的一种含铅电子组件的可靠性,在热力学机械特性试验结果表明由于栅离层的焊线接近引线框架,在键合后从-40℃到125℃的功率热循环下,导致了键合样品的一种电气开路。采用有限元模型模拟了这种封装应力,根据经验检验结果本模拟预示那些在引线键合支撑的焊跟处具有较高的平面剪切力。由数字模拟和试验数据获得的结果可作为选定适当模塑添加剂的一种指导路线。

关键词：可靠性故障分析热膨胀系数平面剪切力 MOS场效应晶体管

Climate Change Perceptions , Impacts and Adaptation Strategies of F arm Households in Potohar Region of Punjab, Pakistan

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Journal of Energy and Power Engineering 2023年第4期17卷 136-151页

作者： Sohaib Aqib Syed Mohsin Ali Kazmi Muhammad Amjad ahmed Ali soomro Ghulam Farooque Khoso Department of Economics Faculty of Economics and Administrative ScienceNear East UniversityNicosia 99138North Cyprus Data Scientist Knowledge CorporationBusiness Center No 310Al Hilal Bank Buildingm AI Tawar AreaAl Qusais 2DubaiUAE Senior Scientific Officer-Global Climate-Change Impact Studies Centre Ministry of Climate ChangeIslamabad 44000Pakistan Depa rtment of Business Administration University of SindhJamshoroSindh 76060Pakistan Department of English Literature and Linguistics University of SindhJamshoroSindh 76060Pakistan

Climate change has become a global phenomenon and is adversely affecting agricultural development across the *** countries like Pakistan where 18.9%of the GDP(gross domestic product)came from the agriculture sector and also 42%of the labor force involved in *** are directly and indirectly affected by climate change due to an increase in the frequency and intensity of climatic extreme events such as floods,droughts and extreme weather *** this paper,we have focused on the impact of climate change on farm households and their adaptation strategies to cope up the climatic *** this purpose,we have selected farm households by using multistage stratified random sampling from four districts of the Potohar region ***,Rawalpindi,Jhelum and *** districts were selected by dividing the Potohar region into rain-fed *** have employed logistic regression to assess the determinants of adaptation to climate change and its *** have also calculated the marginal effect of each independent variable of the logistic regression to measure the immediate rate of change in the *** order to check the significance of our suggested model,we have used hypothesis testing.

关键词： Climate change multistage stratified random sampling impacts adaptation strategies logistic regression marginal effect Hypothesis testing

Effect of Water Stress on the Growth and Yield of Cotton Crop (<i>Gossypium hirsutum</i>L.)

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American Journal of Plant Sciences 2015年第7期6卷 1027-1039页

作者： Arbab Sahito Zulfiqar Ali Baloch Amanullah Mahar Sohail ahmed Otho Shahmir Ali Kalhoro Amjad Ali Fahad Ali Kalhoro Rab Nawaz soomro Fayaz Ali Department of Agronomy Sindh Agriculture University Tando Jam Pakistan College of Economics and Management Sciences Northwest A&F University Yangling China College of Natural Resources and Environment Northwest A&F University Yangling China Centre for Environmental Sciences University of Sindh Jamshoro Pakistan College of Plant Protection Northwest A&F University Yangling China Faculty of Agriculture Lasbela University of Agriculture Water & Marine Sciences Lasbela Pakistan Department of Plant Breeding and Genetics Sindh Agriculture University Tando Jam Pakistan College of Animal Science and Technology Northwest A&F University Yangling China

Cotton is one of the most important fibre crops playing a key role in economic and social affairs of the world. Water is a critical factor which influences on growth and yield of the cotton crop. Scarcity of water has put tremendous pressure on scientists to introduce drought tolerant cotton varieties. This study was aimed to determine water stress effects on the growth and yield of cotton. The present study was carried out to examine the effect of number of irrigations on the growth and yield of cotton during 2014. The field trial was conducted at the Experimental Fields of Agronomy Section, Agriculture Research Institute, Tandojam, Pakistan. A three replicated Randomized Complete Block Design (RCBD) was employed to layout the experiment having plot size of 2.5 m × 5 m (12.5 m2). Four cotton varieties i.e. NIAB-78, Shahbaz-95, Sindh-1 and TH-224/87 were chosen for this study based on their frequent farmer usage. All the agronomic practices were performed according to standard procedures. Results showed that all the growth and yield components of cotton were significantly (P 0.05) affected by irrigation frequencies. The cotton crop irrigated six times at 21 days interval showed better results with 138.16 cm plant height, 1.45 monopodial branches per plant, 21.83 sympodial branches per plant, 44.58 bolls per plant, 33.86% G.O.T., and 26.97 mm staple length, 149.84 g seed cotton yield per plant and 2271.16 kg·ha-1 seed cotton yield. This study concluded that variety NIAB-78 showed superiority over Shahbaz-95, Sindh-1 and TH-224/87 in almost all the characters of economic importance, and the cotton crop received 6 irrigations at 21 days interval resulted in significantly economical overall performance as compared with 5 irrigations or 4 irrigations with higher seed cotton yield.

关键词： Cotton Crop Drought Stress Tolerance Yield