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The Use of MCRD Technique in Mode Shapes Extraction

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Journal of Civil Engineering and Architecture 2010年第7期4卷 26-33页

作者： ahmed. A. Elshafey Mahmoud R. Haddara H. Marzouk Faculty of Engineering Minufiya University St. John＇s Canada Faculty of Engineering and Applied Science Memorial University of Newfoundland St. John＇s Canada Faculty of Engineering Architecture and Science Ryerson University Toronto Ontario Canada

The random decrement technique is an averaging technique that can be used to extract the free decay response of the structure from its random stationary vibratory response. The free decay response can then be used to identify the vibratory characteristics of the structure. The main advantage of the technique is that the identification of the parameters of the structure is achieved without previous knowledge of the excitation forces. This paper extends the random decrement technique to obtain the mode shapes of the structure using the concept of a multichannel random decrement technique （MCRD）. This technique is based on extracting simultaneous random decrement records from measurements made at several points on the structure. The method is very efficient and simple. Numerical examples are solved and compared with the exact mode shapes extracted using classical modal analysis. An excellent agreement between the extracted modes shapes using the MCRD and those obtained from the classical modal analysis techniques is achieved. The vibration of an offshore structure excited by white noise excitation is used to illustrate the method.

关键词： Mode shapes multichannel random decrement free decay

Properties of Fresh and Hardened Self-compacting Concrete Produced by Using Locally Available Materials

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Journal of Civil Engineering and Architecture 2010年第10期4卷 43-50页

作者： ahmed E. Sayed Rabiee A. Seddik Yasser R. Tawfic Department of Civil Engineering A/[inia University El-Minia Egypt

Self-compacting concrete （SCC） is defined so that no vibration is necessary for the compaction. The main criteria of producing SCC have to satisfy the following characteristics [1, 2, 3]：（1） Ability to flow into and completely fill complex forms under its own weight; （2） Ability to pass through and bond to congested reinforcements; （3） High resistance to aggregate segregation. Self-compacting concrete presents a significant sign in improving the product quality and efficiency of the building industry. It also enhances the working conditions and the quality and appearance of concrete. Japan has been used self-compacting concrete in bridge, building and tunnel construction since the early 1990s. In the last decade, SCC has been produced a high potential for greater acceptance and wider applications in highway bridge construction in the Europe and U.S.. However, till now, there is no application of SCC in the construction industry in Egypt. Therefore, the main objective of this research is to produce SCC by using the locally available materials in our region such as basalt, gravel, sand, limestone powder and silica fume. Experimental programme was designed to characterize the properties of fresh and hardened SCC. It comprises different concrete mixes thbricated with different types and percentages of constituent materials. Three full-scale reinforced concrete beams were fabricated from the SCC mixes and tested under flexure. For the purpose of comparison, an extra RC beam was made of conventional normal concrete to serve as a reference beam. This study, in general, demonstrated that the applications of SCC in construction industry oiler products with enhanced characteristics as well as could be economical.

关键词： Self-compacting concrete (SCC) lime stone powder silica fume workability slump flow L-Box test.

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能量消耗感知的虚拟网络嵌入算法的研究

能量消耗感知的虚拟网络嵌入算法的研究

作者：艾哈迈德（ahmed ZAFAR）北京交通大学

学位级别：硕士

通信技术已成为社会数字化不可分割的一部分,并对全球国内生产总值（GDP）增长做出了重要贡献。物联网（IOT）概念的诞生将未来带入了一个新的方向。物联网（IOT）指的是扩展网络连接到物理设备和日常用品。具体来说物联网（Internet of... 详细信息

通信技术已成为社会数字化不可分割的一部分,并对全球国内生产总值（GDP）增长做出了重要贡献。物联网（IOT）概念的诞生将未来带入了一个新的方向。物联网（IOT）指的是扩展网络连接到物理设备和日常用品。具体来说物联网（Internet of Things）指的是将无处不在的末端设备和设施,包括具备“内在智能”的传感器、移动终端、工业系统、楼控系统、家庭智能设施、视频监控系统等、和“外在使能”（Enabled）的,如贴上RFID的各种资产)、携带无线终端的个人与车辆等“智能化物件或动物”或“智能尘埃”,通过各种无线和/或有线的长距离和/或短距离通讯网络实现互联互通、应用大集成、以及基于云计算的营运等模式,在内网)、专网)、和/或互联网环境下,采用适当的信息安全保障机制,提供安全可控乃至个性化的实时在线监测、定位追溯、报警联动、调度指挥、预案管理、远程控制、安全防范、远程维保、在线升级、统计报表、决策支持、领导桌面等管理和服务功能,实现对“万物”的“高效、节能、安全、环保”的“管、控、营”一体化。。在嵌入式系统的设计中,除了需要系统为给定的输入产生所需的输出,还有其他方面也需要得到满足。新的技术突破和生产的大规模化为普通人提供了更容易使用的廉价产品,这使得新兴技术在全球范围内的大规模的使用。技术进步（更普遍来说-现代文明）的主要推动力之一是促进这些设备高效运行的能源。然而,由于各种各样工业技术在全球范围内的使用,社会生产以及工业中对于能源有了越来越多的需求。因此,如何通过减少燃烧功率来达到恰好的社会需求,是一个很大的挑战。互联网服务供应商（isp）正面临着尽量减少电力/能源消耗的挑战。最近,学界和业界致力于减少服务器和网络级别的能源消耗。网络虚拟化被认为不仅是克服当前互联网基础设施缺乏灵活性的组织者,而且是实现节能未来互联网的推动者。网络虚拟化就是在一个物理网络上模拟出多个逻辑网络来。网络虚拟化的内容一般指虚拟专用网络（VPN）。VPN对网络连接的概念进行了抽象,允许远程用户访问组织的内部网络,就像物理上连接到该网络一样。网络虚拟化可以帮助保护IT环境,防止来自Internet的威胁,同时使用户能够快速安全的访问应用程序和数据。与此同时,虚拟网络嵌入（VNE）是网络虚拟化技术中的一个关键问题。近年来,由于在互联网环境下打开/关闭不使用的设备可以节省能源,人们致力于研究嵌入在VN中的不同功耗模型下的功率感知VNE问题。本文针对VNE系统的低能耗问题,讨论了联合功率感知节点和链路资源分配方法。在全文中,首先,我们提出了一个嵌入VN的广义功耗模型（GPC）。此外,该GPC模型可以获得与物理节点和网络设备相连接的固定和可变功耗的任何组合。然后将该问题转化为一个混合整数规划和两个具有较好协调能力的嵌入算法。仿真结果表明,在电力供应过剩的情况下,该算法的功率性能优于现有算法。然而,我们实际上也匹配了6种算法的性能,即ENM-SNP,ENM-SPN,RW-SNP,RW-SPN,R-Vi NE-SNP,and R-Vi NE-SPN.而“RW”表示使用文中提出的能量感知节点映射算法来映射虚拟节点。在此基础上,我们进一步的研究了不同功耗模型下嵌入VN的功率感知VNE问题。我们的其他工作贡献是,在降低能源成本方面提出了正式的GPC模型和形成了GPC-PE-VNE问题。在此基础上,我们给出了针对以上问题的线性规划公式和嵌入算法。我们评估了我们提出的算法的性能,并将其与现有算法在期限或能源消耗方面进行了比较。分析结果表明,我们提出的算法比现有的算法有更好的结果。最后,提出了今后改进和推广这一工作的可能途径。

关键词：网络虚拟化虚拟网络嵌入能耗优化资源分配

A GIS-Based Drastic Model for Assessing Aquifer Vulnerability in Amman-Zerqa Groundwater Basin, Jordan

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Engineering（科研） 2013年第5期5卷 490-504页

作者： Abdulla Mal-Rawabdeh Nadhir Aal-Ansari ahmed Aal-Taani Sven Knutsson Department of Geomatics Engineering University of CalgaryAlbertaCanada Department of Civil Environmental and Natural Resources and EngineeringLulea University of TechnologyLuleaSweden UNESCO Chair for Desert Studies and Desertification Control Yarmouk UniversityIrbidJordan

Amman-Zerqa Basin (AZB) is a major basin in Jordan. The concentration of economic, agricultural and social activities within the basin makes it of prime importance to Jordan. Intensive agricultural practices are widespread and located close to groundwater wells, which pose imminent threats to these resources. Groundwater contamination is of particular concern as groundwater resources are the principal source of water for irrigation, drinking and industrial activities. A DRASTIC model integrated with GIS tool has been used to evaluate the groundwater vulnerability of AZB. The Drastic index map showed that only 1.2% of the basin’s total area of 3792 km2 lies in the no vulnerable zone and about 69% is classified as having low pollution potential. The results also revealed that about 30% of the catchment area is moderately susceptible to pollution potential and slightly 1% is potentially under high pollution risk. These results suggest that almost one third of the AZB is at moderate risk of pollution potential. These areas are mainly in the north-east and central parts of the basin where the physical factors (gentle slope and high water table) would allow more contaminants to easily move into the shallow groundwater aquifer. Areas with high vulnerability to pollution are largely located in the center of Amman old city.

关键词： Amman-Zerqa Basin Jordan GIS DRASTIC

Fabrication and Characterization of Graphene Incorporated Cu Based Perovskite in Application of Perovskite Solar Cell under Ambient Condition

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Advances in Materials Physics and Chemistry 2020年第1期10卷 1-16页

作者： Shah Sultan Ashrafi Kamal Hossain Farid ahmed Abul Hossain Obaidur Rahman Department of Physics Jahangirnagar University Dhaka Bangladesh

In this work, we demonstrate the synthesis and characterization of Cu-based thin film perovskites and their prospective application in photovoltaic cells and light-harvesting devices, which is lead(Pb) free and environmental friendly. We studied valuable part of graphene for stability issue in CH3NH3CuCl3(MACuCl3) Perovskites solar cell and improved band gap 2.61 eV to 2.56 eV as well. Copper ions represented responsible of this materials for the bright green photoluminescence. For assimilating MACuCl3 and G-MACuCl3 based Perovskites, solar cells architectures and photovoltaic performance are argued among them. The main limitations for the solar cell efficiency were found the arrangement of insubstantial mass and high absorption coefficient of the electrons as well. As per as our knowledge, this work is demonstrated of the prospective of thin film MACuCl3 and G-MACuCl3 perovskite as light absorber and puts down the establishment for additional development of perovskite solar cell as alternative of lead-free materials.

关键词： Demonstration Perovskites Light-Harvesting MACuCl3 Absorber Photoluminescence

Crop Discrimination Using Field Hyper Spectral Remotely Sensed Data

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Advances in Remote Sensing 2013年第2期2卷 63-70页

作者： Sayed M. Arafat Mohamed A. Aboelghar Eslam F. ahmed Agriculture Applications Department National Authority for Remote Sensing and Space Sciences (NARSS)Cairo Egypt

Crop discrimination through satellite imagery is still problematic. Accuracy of crop classification for high spatial resolution satellite imagery in the intensively cultivated lands of the Egyptian Nile delta is still low. Therefore, the main objective of this research is to determine the optimal hyperspectral wavebands in the spectral range of (400 - 2500 nm) to discriminate between two winter crops (Wheat and Clover) and two summer crops (Maize and Rice). This is considered as a first step to improve crop classification through satellite imagery in the intensively cultivated areas in Egypt. Hyperspectral ground measurements of ASD field Spec3 spectroradiometer was used to monitor the spectral reflectance profile during the period of the maximum growth stage of the four crops. 1-nm-wide was aggregated to 10-nm-wide bandwidths. After accounting for atmospheric windows and/or areas of significant noise, a total of 2150 narrow bands in 400 - 2500 nm were used in the analysis. Spectral reflectance was divided into six spectral zones: blue, green, red, near-infrared, shortwave infrared-I and shortwave infrared-II. One Way ANOVA and Tukey’s HSD post hoc analysis was performed to choose the optimal spectral zone that could be used to differentiate the different crops. Then, linear regression discrimination (LDA) was used to identify the specific optimal wavebands in the spectral zones in which each crop could be spectrally identified. The results of Tukey’s HSD showed that blue, NIR, SWIR-1 and SWIR-2 spectral zones are more sufficient in the discrimination between wheat and clover than green and red spectral zones. At the same time, all spectral zones were quite sufficient to discriminate between rice and maize. The results of (LDA) showed that the wavelength zone (727:1299 nm) was the optimal to identify clover crop while three zones (350:712, 1451:1562, 1951:2349 nm) could be used to identify wheat crop. The spectral zone (730:1299 nm) was the optimal to identify maize

关键词： Hyper Spectral Data Crop Discrimination

Value of Different Diagnostic Markers in Spontaneous Bacterial Peritonitis in HCV Egyptian Cirrhotic Patients

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Open Journal of Gastroenterology 2015年第9期5卷 119-128页

作者： Emad M. El Motasem ahmed A. Heikal Hemmat E. El Haddad ahmed Hamdy Rasha M. Abdel Samie Heba Sharaf El Din Internal Medicine Department Faculty of Medicine Cairo University Cairo Egypt Clinical and Chemical Pathology Department Faculty of Medicine Cairo University Cairo Egypt

Background: Spontaneous bacterial peritonitis (SBP) is a life-threatening infection occurring in 8% - 30% of ascitic cirrhotic patients;different laboratory diagnostics play a pivotal role for rapid and effective management of SBP patients. Polymorphonuclear leucocytic (PMNLs) count in Ascitic fluid (AF) is the mainstay for the diagnosis, whereas the diagnostic role of alternative biomarkers is rather controversial. In many studies, serum lipopolysaccharide binding protein (LBP) was elevated and Complement 3 (C3) level was significantly consumed in AF of SBP patients. Objectives: To evaluate the diagnostic value of serum LBP and AF C3 in HCV-cirrhotics with SBP in relation to other well-established serum and AF markers. Patients and Methods: One hundred and twenty patients with HCV-cirrhosis and ascites were enrolled and consented: 50 patients with non-SBP ascites in group A and 70 ascitic patients diagnosed with SBP according to clinical suspicion and PMLs count in AF ≥ 250 cells/mm3 in group B in addition to 15 healthy individuals considered as a control group. Serum LBP, CBC, kidney and liver function tests, CRP, fasting and 2 h PP blood glucose and HCV antibodies were measured. AF samples were sent for C3 level, culture, PMNLs count, LDH, CRP, total proteins and albumin. Results: In patients with SBP, the level of serum LBP was not significantly high (p > 0.05) with best cut off value at 0.4500 and poor AUC (alue at 144.2 and almost excellent AUC (0.889) with good sensitivity and specificity (82% & 84%, respectively). AF culture showed significant difference between both patients groups (p < 0.05) but with low sensitivity (33.3%). Serum and AF CRP and AF PMNLs count were of high significance in SBP diagnosis (p < 0.001). Conclusion: Serum LBP level showed low significance while AF C3 was significantly reduced in patients

关键词： Spontaneous Bacterial Peritonitis-Serum Lipopolysaccharide Binding Protein-Ascitic Fluid Complement 3-C-Reactive Protein-Ascitic Fluid Culture

Hydrogeochemical evaluation and statistical analysis of groundwater of Sylhet, north-eastern Bangladesh

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Acta Geochimica 2019年第3期38卷 440-455页

作者： Nasir ahmed Md.Bodrud-Doza S.M.Didar-Ul Islam Manzoor Ahmad Choudhry Md.Iftakharul Muhib Anwar Zahid Shahadat Hossain Md.Moniruzzaman Nipa Deb Md.Abdul Quaiyum Bhuiyan Isotope Hydrology Division Institute of Nuclear Science and Technology Atomic Energy Research Establishment Department of Environmental Sciences Jahangirnagar University Isotope Hydrology Section Department of Nuclear Sciences and Applications International Atomic Energy Agency Groundwater Hydrology Bangladesh Water Development Board

To investigate the hydrogeochemical characteristics of groundwater 23 shallow, 30 intermediate and 38 deep wells samples were collected from Sylhet district of Bangladesh, and analyzed for temperature, pH, Eh, EC,DO, DOC, Na^+, K^+, Ca^(2+), Mg^(2+), Cl^-, SO_4^(2-), NO_3^-,HCO_3^-, SiO_2^-, Fe, Mn and As. Besides, 12 surface water samples from Surma and Kushiyara Rivers were also collected and analyzed to understand the influence into aquifers. Results revealed that, most of the groundwater samples are acidic in nature, and Na–HCO_3 is the dominant groundwater type. The mean value of temperature, EC,Na^+, K^+, Ca^(2+), Mg^(2+), Cl^-, NO_3^- and SO_4^(2-) were found within the range of permissible limits, while most of the samples exceeds the allowable limits of Fe, Mn and As concentrations. However, relatively higher concentration of Fe and Mn were found in deep water samples and reverse trend was found in case of As. The mean concentrations of As in shallow, intermediate and deep wells were 39.3, 25.3and 21.4 lg/L respectively, which varied from 0.03 to148 lg/L. From spatial distribution, it was found that Fe,Mn and As concentrations are high but patchy in northern,north-western, and south-western part of Sylhet region. The most influential geochemical process in study area were identified as silicate weathering, characterized by active cation exchange process and carbonate weathering, which thereby can enhance the elemental concentrations in groundwater. Pearson's correlation matrix, principal component analysis and cluster analysis were also employed to evaluate the controlling factors, and it was found that, both natural and anthropogenic sources were influencing the groundwater chemistry of the aquifers. However, surface water has no significant role to contaminate the aquifers,rather geogenic factors affecting the trace elemental contamination. Thus it is expected that, outcomes of this study will provide useful insights for future groundwater monitoring and

关键词： Arsenic Groundwater Hydrogeochemistry Multivariate statistics Spatial distribution

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