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Condition Assessment of August A. Busch Bridge Deck Using Portable Seismic Property Analyzer and Ground Penetrating Radar

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Open Journal of Civil Engineering 2022年第1期12卷 14-21页

作者： Samie hamad Wajdi Ammar Salah Shaniba Abdelmajeed Altlomate Missouri University of Science and Technology Missouri USA University of Colorado Denver Colorado USA Mellitah Oil & Gas B.V Tripoli Libya Sirte University Sirte Libya

Ground penetrating radar (GPR) and the portable seismic property analyzer (PSPA) have been extensively used in the past two decades for monitoring, quantifying, and mapping the deterioration of bridge decks. Using PSPA and GPR ensures regular monitoring of bridge conditions, leads to the early detection of deterioration. This research is to address the condition of August A. Busch bridge deck owned by the Missouri Department of Conservation. Visual inspection, GPR, and PSPA data were acquired on the bridge deck. Over 90% of the bridge deck was in fair to good condition with an average compressive strength of over 2500 psi. GPR data showed no indication of significant deterioration. The overall bridge deck was determined to be in fair to good condition.

关键词： Ground Penetrating Radar Portable Seismic Property Analyzer Bridge Deck Concrete Deterioration

Ameliorative Effect of Shade on Seedling Growth—Evidence from Field Experiment of <i>Vachellia farnesiana</i>(L.) Willd

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American Journal of Plant Sciences 2019年第1期10卷 12-23页

作者： Nurul Iman Suansa hamad A. Al-Mefarrej Plant Production Department College of Food and Agriculture Sciences King Saud University Riyadh KSA

The presence of species diversity in the ecosystem is an important aspect. Simply put, the loss of biodiversity and the formation of ecosystems into monocultures would reduce the productivity of the forest ecosystem than it has abundant diversity. This study conducted with a purpose to get the basic information regarding the effect of shade on the seedling growth. Understanding these relationships in the early years may reveal the important information, which will be helpful for managing and evaluating the silviculture practices. The study was conducted at Dirab Experiments and Agricultural Research Station, South of Riyadh. The experimental plot was managed under the corridor of Eucalyptus camaldulensis stands. Twenty seedlings of Vachellia farnesiana with relative similar height and diameter were planted in each block at a 5 × 5 m2 spacing in March 2017. Three different treatments were established and relatively categorized into Line 1 (without shade), Line 2 (shade until 09:00 a.m.), and Line 3 (shade until 11:00 a.m.). Eight months after planting, several morphological parameters were monthly assessed from November 2017 until April 2018. Also, the number of fruits was observed following the fruit’s season. Seedling growth variation as an effect of shading occurred between the lines of planting in this experiment. The seedling growth was significantly increased by shading treatment, even though target plant species (V. farnesiana) is categorized as intolerant species. Basically, shade helps to generate the favorable local environment for supporting plant growth. This treatment with an appropriate consideration might become an alternative practice for increasing plant productivity.

关键词： Vachellia farnesiana Underplanting Shade Tolerance Ameliorative Effect

A Regression Type Estimator with Two Auxiliary Variables for Two-Phase Sampling

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Open Journal of Statistics 2013年第2期3卷 74-78页

作者： Naqvi hamad Muhammad Hanif Najeeb Haider Department of Statistics Government Postgraduate College Dera Ghazi Khan Pakistan National College of Business Administration and Economics Lahore Pakistan

This paper is an extension of Hanif, hamad and Shahbaz estimator [1] for two-phase sampling. The aim of this paper is to develop a regression type estimator with two auxiliary variables for two-phase sampling when we don’t have any type of information about auxiliary variables at population level. To avoid multi-collinearity, it is assumed that both auxiliary variables have minimum correlation. Mean square error and bias of proposed estimator in two-phase sampling is derived. Mean square error of proposed estimator shows an improvement over other well known estimators under the same case.

关键词： Mean Square Error Precision Two-Phase Sampling Auxiliary Variable Regression Type Estimator Simple Random Sampling without Replacement

On Two Double Inequalities (Optimal Bounds and Sharps Bounds) for Centroidal Mean in Terms of Contraharmonic and Arithmetic Means

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Journal of Applied Mathematics and Physics 2020年第6期8卷 1039-1046页

作者： Mohammed El Mokhtar Ould El Mokhtar hamad Alharbi Qassim University Al-Mulida Qassim KSA Shaqra University Shaqra KSA

This research work considers the following inequalities: λA(a,b) + (1-λ)C(a,b) ≤ C(a,b) ≤ μA(a,b) + (1-μ)C(a,b) and C[λa + (1-λ)b, λb + (1-λ)a] ≤ C(a,b) ≤ C[μa + (1-μ)b, μb + (1-μ)a] with . The researchers attempt to find an answer as to what are the best possible parameters λ, μ that (1.1) and (1.2) can be hold? The main tool is the optimization of some suitable functions that we seek to find out. By searching the best possible parameters such that (1.1) and (1.2) can be held. Firstly, we insert f(t) = λA(a,b) + (1-λ)C(a,b) - C(a,b) without the loss of generality. We assume that a>b and let to determine the condition for λ and μ to become f (t) ≤ 0. Secondly, we insert g(t) = μA(a,b) + (1-μ)C(a,b) - C(a,b) without the loss of generality. We assume that a>b and let to determine the condition for λ and μ to become g(t) ≥ 0.

关键词： Centroidal Mean Arithmetic Mean Contraharmonic Mean

Tanzania Olympic Games and the Liberation of Southern Africa

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Tanzania Olympic Games and the Liberation of Southern Africa

A Numerical Method for Singular Boundary-Value Problems

北京论坛（2006）文明的和谐与共同繁荣—对人类文明方式的思考

作者： hamad S.Ndee University of Dar es Salaam Department of Physical Education Sport and Culture

前言当历史步入21世纪之时,人们赫然发现,以经济为先导的全球化潮流正在势不可挡地席卷着整个世界,它将不同地理空间、不同历史时间的文化传统带到了当下的全球场景之中,处于同一时空背景下的异质文化不断发生着碰撞、冲突、交融、共生...

前言当历史步入21世纪之时,人们赫然发现,以经济为先导的全球化潮流正在势不可挡地席卷着整个世界,它将不同地理空间、不同历史时间的文化传统带到了当下的全球场景之中,处于同一时空背景下的异质文化不断发生着碰撞、冲突、交融、共生。体育这一人类共同的语言,也伴随着全球化的大趋势超越了空间环境和人文壁垒,使不同地域、民族的体育文化进行着多元碰撞与融合。产生于工业革命背景下的现代奥林匹克体育,早在19

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Journal of Applied Mathematics and Physics 2014年第9期2卷 882-887页

作者： Abdalkaleg hamad M. Tadi Miloje Radenkovic Department of Electrical Engineering University of Colorado at Denver Denver USA Department of Mechanical Engineering University of Colorado at Denver Denver USA

This note is concerned with an iterative method for the solution of singular boundary value problems. It can be considered as a predictor-corrector method. Sufficient conditions for the convergence of the method are i... 详细信息

关键词： Singular Boundary-Value Problem Singularly Perturbed Boundary Value Problem

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低碳经济背景下石油企业价值分析研究

低碳经济背景下石油企业价值分析研究

作者： ABDULLZIZ hamad ALOTAIBI 华南理工大学

学位级别：硕士

排碳大户石油企业作为碳中和与碳达峰目标的重要践行者,被期许的低碳经济形态越来越被中国人民所关心。在此背景下,增加减排技术投入,参与碳交易市场和研发环保石油产品等技术方案被石油企业逐步采纳,这也对石油企业价值造成了一定的影... 详细信息

排碳大户石油企业作为碳中和与碳达峰目标的重要践行者,被期许的低碳经济形态越来越被中国人民所关心。在此背景下,增加减排技术投入,参与碳交易市场和研发环保石油产品等技术方案被石油企业逐步采纳,这也对石油企业价值造成了一定的影响。为此,有必要对低碳经济背景下的石油企业价值进行研究,以确保石油企业的健康有序发展。本文的主要内容和创新点如下:以中国上海证券交易所A股中的石油上市公司为研究对象,依据公开的财报和官方新闻对其低碳行为对企业价值的影响进行理论分析和实证分析。在理论分析方面,界定了石油企业的低碳行为,并进一步分析了与企业价值相关的内生和外生影响因素。在实证分析方面,将石油企业的低碳经济行为分为碳信息披露质量水平和低碳投入,结合单位根检验、模型设定形式检验、Hausman检验和回归性检验对石油企业的低碳行为影响程度进行了分析。算例分析表明,在中国,石油企业的低碳经济行为对企业价值并无很显著的正向影响,但这可能是国内碳政策颁布的时间不久导致的,或者碳信息披露制度不完善导致的。在此基础上,对涉及的利益方,如石油上市公司、监管机构和投资者,给出了一些建议。为了进一步解释石油企业的低碳经济行为对企业价值的影响,在分析正向和负向影响的基础上,将企业价值划分为经济价值和低碳价值。对于前者,将因生产经营中的低碳经济行为创造的经济效益定义为经济价值;对于后者,将因减碳为石油企业带来的潜在获利定义为低碳价值。算例部分依托某石化企业的实际数据,采用现金流量折现法和实物期权法对经济价值和低碳价值进行测算,其结果表明低碳经济行为会对企业价值的累加起到促进作用。中国和沙特阿拉伯的减碳计划给国家的能源结构构成了挑战,特别是沙特阿拉伯这种高度依赖石油的国家。在这个背景下,传统石油企业评估指标体系不能有效考虑节能减碳的影响。为此,在这篇文章,围绕产品价值、顾客价值和社会价值构建考虑节能减碳效益的石油企业价值评估指标体系,可较全面的反映石油企业价值情况。为解决该指标体系的模糊性和难量化性,结合五标度层次分析法和熵值法对安全风险指标进行组合赋权,再提出了基于云理论的石油企业价值评估方法。基于此构建的多级指标云图可兼顾多位专家的主客观意见,以及较为敏锐的识别高价值的石油企业价值。算例以6位专家对所提石油企业价值评估指标体系的评分为基础,有效验证了所提方法的科学性,对实践中石油企业价值的评估具有一定的裨益。

关键词：石油企业低碳经济企业价值碳信息披露质量水平云模型

TANZANIA,THE OLYMPIC GAMES AND THE LIBERATION OF SOUTHERN AFRICA

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TANZANIA,THE OLYMPIC GAMES AND THE LIBERATION OF SOUTHERN AF...

Synthesis of N-Substituted （Z）-3-（（2-Benzyl）-4-Ox opent-2-yl） Pyrrole-2,5-Diones （Maleimides）

北京论坛（2006）文明的和谐与共同繁荣—对人类文明方式的思考

作者： hamad S.Ndee University of Dar es Salaam Department of Physical Education Sport and Culture

Introduction Throughout the 1950s,Tanzania(by then Tanganyika) was engaged in a liberation struggle,a struggle that eventually saw the country become independent from the British trusteeship in *** after gaining her independence,Tanzania,under the leadership of Julius Kambarage Nyerere,committed herself to the liberation of the whole of *** involved liberating those countries which were still under colonial rule and bringing about political change in those countries which were under oppressive *** particular,Tanzania set out to influence political change in the former apartheid South Africa and in the former white minority-ruled Southern Rhodesia(now Zimbabwe).

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Journal of Chemistry and Chemical Engineering 2014年第11期8卷 1018-1025页

作者： Isra Salih Ad-Daraji Albdulmajeed Salih hamad Alsamarrai Department of Chemistry College of Education University of Samarra Salahalddin 131333 Iraq Department of Applied Chemistry College of Applied Science University of Samarra Salahalddin 131333 Iraq

A series of N-substituted （Z）-3-（（2-benzyl）-4-oxopent-2-yl）pyrrole-2,5-diones were synthesized and characterized. The compounds were synthesized from dimethyl-2-（（Z）-2-（benzylamino）-4-oxopent-2-en-3-yl） fumarate （9） and dimethyl acetylenedi-carboxylate followed by reaction with some amines in refluxing ethanol. The identification of the compounds were based on spectroscopic analysis such as 1R （infrared）, UV （ultraviolet）, ^1H-NMR （nuclear magnetic resonance） and the microanalysis of the elements （CHN （microanalysis）） data.

关键词： Maleimides N-substituted pyrrole-2 5-dione aromatic amines dimethyl acetylene dicarboxylate