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Impacts of environmental factors on urban heating

Journal of Environmental Sciences 2010年第12期22卷 1903-1909页

作者： rizwan ahmed memon Dennis Y.C.Leung Department of Mechanical Engineering Mehran University of Engineering & Technology Department of Mechanical Engineering The University of Hong Kong School of Energy and Environment City University of Hong Kong

This study investigated the impact of important environmental variables （i.e., wind speed, solar radiation and cloud cover） on urban heating. Meteorological parameters for fifteen years （from 1990 to 2005）, collected at a well developed and densely populated commercial area （Tsim Sha Tsui, Hong Kong）, were analyzed in details. Urban heat island intensity （UHII）, a well known indicator of urban heating, has been determined as the spatially averaged air-temperature difference between Tsim Sha Tsui and Ta Kwu Ling （a thinly populated rural area with lush vegetation）. Results showed that the UHII and cloud cover have increased by around 9.3% and 4%, respectively, whereas the wind speed and solar radiation have decreased by around 24% and 8.5%, respectively. The month of December experienced the highest UHII （10.2℃） but the lowest wind speed （2.6 m/sec） and cloud cover （3.8 oktas）. Conversely, the month of April observed the highest increases in the UHII （over 100%） and the highest decreases in wind speed （over 40 %） over fifteen years. Notably, the increases in the UHII and reductions in the wind speed were the highest during the night-time and early morning. Conversely, the intensity of solar radiation reduced while the intensity of urban cool island （UCII） increased during solar noon-time. Results demonstrated strong negative correlation between the UHII and wind speed （coefficient of determination, R^2 = 0.8） but no negative correlation between UCII and solar radiation attenuation. A possible negative correlation between UHII and cloud cover was investigated but could not be substantiated.

关键词： urban heat island urban cool island wind speed cloud cover

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A review on the generation, determination and mitigation of Urban Heat Island

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Journal of Environmental Sciences 2008年第1期20卷 120-128页

作者： rizwan ahmed memon DENNIS Y.C. Leung LIU Chunho Department of Mechanical Engineering the University of Hong Kong Hong Kong China.

Urban Heat Island （UHI） is considered as one of the major problems in the 21st century posed to human beings as a result of urbanization and industrialization of human civilization. The large amount of heat generated from urban structures, as they consume and re-radiate solar radiations, and from the anthropogenic heat sources are the main causes of UHI. The two heat sources increase the temperatures of an urban area as compared to its surroundings, which is known as Urban Heat Island Intensity （UHII）. The problem is even worse in cities or metropolises with large population and extensive economic activities. The estimated three billion people living in the urban areas in the world are directly exposed to the problem, which will be increased significantly in the near future. Due to the severity of the problem, vast research effort has been dedicated and a wide range of literature is available for the subject. The literature available in this area includes the latest research approaches, concepts, methodologies, latest investigation tools and mitigation measures. This study was carded out to review and summarize this research area through an investigation of the most important feature of UHI. It was concluded that the heat re-radiated by the urban structures plays the most important role which should be investigated in details to study urban heating especially the UHI. It was also concluded that the future research should be focused on design and planning parameters for reducing the effects of urban heat island and ultimately living in a better environment.

关键词： urban heat island (UHI) urbanization temperature rise mitigation

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Effect of silica fume on the fresh and hardened properties of fly ash-based self-compacting geopolymer concrete

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International Journal of Minerals,Metallurgy and Materials 2013年第2期20卷 205-213页

作者： Fareed ahmed memon Muhd Fadhil Nuruddin Nasir Shafiq Department of Civil Engineering Faculty of EngineeringUniversiti Teknologi PETRONAS Department of Civil Engineering Faculty of EngineeringMehran University of Engineering and Technology

The effect of silica fume on the fresh and hardened properties of fly ash-based self-compacting geopolymer concrete （SCGC） was investigated in this paper. The work focused on the concrete mixes with a fixed water-to-geopolymer solid （W/Gs） ratio of 0.33 by mass and a constant total binder content of 400 kg/m3. The mass fractions of silica fume that replaced fly ash in this research were 0wt%, 5wt%, 10wt%, and 15wt%. The workability-related fresh properties of SCGC were assessed through slump flow, V-funnel, and L-box test methods. Hardened concrete tests were limited to compressive, splitting tensile and flexural strengths, all of which were measured at the age of 1, 7, and 28 d after 48-h oven curing. The results indicate that the addition of silica fume as a partial replacement of fly ash results in the loss of workability; nevertheless, the mechanical properties of hardened SCGC are significantly improved by incorporating silica fume, especially up to 10wt%. Applying this percentage of silica fume results in 4.3% reduction in the slump flow; however, it increases the compressive strength by 6.9%, tensile strength by 12.8% and flexural strength by 11.5%.

关键词： geopolymer concrete silica fume fresh properties compressive strength tensile strength flexural strength

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An Open IoT Framework Based on Microservices Architecture

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China Communications 2017年第2期14卷 154-162页

作者： Long Sun Yan Li Raheel ahmed memon College of Computer Science Sichuan University Chengdu 610064 China College of manufacturing Science and Engineering Sichuan University Chengdu 610064 China School of Computer Science University of Engineering Science and Technology Chengdu 610064 China Department of Computer Science Sukkur Institute of Business Administration Sukkur Sindh Pakistan

With the continuous development and evolvement of Internet of Things （IoT）, monolithic application becomes much larger in scale and even more complex in structure. This leads to poor scalability, extensibility and maintainability. In response to those challenges, microservice architecture has been introduced in the field of IoT application, due to its flexibility, lightweight and loose coupling. However, the existing loT framework of microservice mainly focus on a specific domain, therefore, this greatly limits its application. In this paper, we propose a general microservice system framework for the loT application, which is a better scalable, extendable and maintainable architecture. We introduce its system design and related microservices, and emphasize on core service and device communication from service layer to physical layer. It has better capacity to support interoperability and accommodate heterogeneous objects. In addition, this framework can easily achieve more application integration such as automation, intelligence, Geo service and Big Data.

关键词： Internet of things loT micro service software architecture

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Fault Detection and Identification Using Deep Learning Algorithms in Induction Motors

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Computer Modeling in Engineering & Sciences 2022年第11期133卷 435-470页

作者： Majid Hussain Tayab Din memon Imtiaz Hussain Zubair ahmed memon Dileep Kumar Department of Electronic Engineering Quaid-e-Awam University of Engineering Science and TechnologyNawabshah67480Pakistan NCRA Condition Monitoring Systems Lab Mehran University of Engineering and TechnologyJamshoro76062Pakistan Department of Electronic Engineering Mehran University of Engineering and TechnologyJamshoro76062Pakistan Design and Creative Technology Torrens University AustraliaMelbourneAustralia Department of Electronics and Power Engineering Pakistan Navy Engineering College NUSTKarachi75350Pakistan

Owing to the 4.0 industrial revolution condition monitoring maintenance is widely accepted as a useful approach to avoiding plant disturbances and ***,Motor Current Signature Analysis(MCSA)is widely reported as a condition monitoring technique in the detection and identification of individual andmultiple Induction Motor(IM)***,checking the fault detection and classification with deep learning models and its comparison among them selves or conventional approaches is rarely reported in the ***,in this work,wepresent the detection and identification of induction motor faults with MCSA and three Deep Learning(DL)models namely MLP,LSTM,and ***,we have developed the model of Squirrel Cage induction motor in MATLAB and simulated it for single phasing and stator winding faults(SWF)using Fast Fourier Transform(FFT),Short Time Fourier Transform(STFT),and Continuous Wavelet Transform(CWT)to detect and identify the healthy and unhealthy conditions with phase to ground,single phasing and in multiple fault conditions using Motor Current Signature *** faults impact on stator current is presented in the time and frequency domain(i.e.,power spectrum).The simulation results show that the scalogram has shown good results in time-frequency analysis for fault and showing its impact on the energy of current during individual fault and multiple fault *** is further investigated with three deep learning models(i.e.,MLP,LSTM,and 1D-CNN)for checking the fault detection and identification(i.e.,classification)improvement in a three-phase induction *** simulating the three-phase induction motor in various healthy and unhealthy conditions in MATLAB,we have collected current signature data in the time domain,labeled them accordingly and created the 50 thousand samples dataset for DL *** the DL models are trained and validated with a suitable number of architecture *** simulation,the multiclass confusion

关键词： Condition monitoring motor fault diagnosis stator winding faults deep learning signal processing

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A unified approach of energy and data cooperation in energy harvesting WSNs

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Science China(Information Sciences) 2018年第8期61卷 170-182页

作者： Roomana YOUSAF rizwan AHMAD Waqas ahmed Fu-chun ZHENG School of Electrical Engineering and Computer Science National University of Sciences and Technology Department of Electrical Engineering Pakistan Institute of Engineering and Applied Sciences School of Electronic and Information Engineering Harbin Institute of Technology

Energy harvesting(EH) provisioned wireless sensor nodes are key enablers to increase network life time in modern wireless sensor networks(WSNs). However, the intermittent nature of the EH process necessitates management of nodes’ limited data and energy buffer capacity. In this paper, a unified mathematical model for a cooperative EHWSN with an opportunistic relay is presented. The energy and data causality constraints are expressed in terms of throughput, available energy, delay and transmission *** finite energy buffers, data buffers and discrete transmission rates(as defined in the standard IEEE 802.15.4) at the nodes, different intuitive online power allocation policies at the relay are *** results show that a policy achieving high throughput is less fair and vice versa. Therefore, a joint rate and power allocation policy(JRPAP) is proposed in this study which provides a better trade off between fairness, throughput and energy over intuitive policies. Based on the JRPAP results, we propose to use data aggregation(DA) to achieve throughput gain at lower buffer sizes. In addition, the notion of energy aggregation(EA) is introduced to achieve throughput gain at higher buffer sizes. Combining both EA and DA further improves the overall throughput at all buffer sizes.

关键词： energy harvesting energy causality data causality energy aggregation data aggregation opportunistic relay

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Saliency-based framework for facial expression recognition

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Frontiers of Computer Science 2019年第1期13卷 183-198页

作者： rizwan ahmed KHAN Alexandre MEYER Hubert KONIK Saida BOUAKAZ Universite de Lyon CNRSLIRISUMR5205Universite Lyon 1Lyon F-69622France Faculty of Information Technology Barrett Hodgson UniversityKarachi 74900Pakistan Laboratoire Hubert Curien UMR5516Universite Jean MonnetSaint-Etienne 42000France

This article proposes a novel framework for the recognition of six universal facial *** framework is based on three sets of features extracted from a face image:entropy,brightness,and local binary ***, saliency maps are obtained using the state-of-the-art saliency detection algorithm "frequency-tuned salient region detection".The idea is to use saliency maps to determine appropriate weights or values for the extracted features (i.e.,brightness and entropy).We have performed a visual experiment to validate the performance of the saliency detection algorithm against the human visual *** movements of 15 subjects were recorded using an eye-tracker in free-viewing conditions while they watched a collection of 54 videos selected from the Cohn-Kanade facial expression *** results of the visual experiment demonstrated that the obtained saliency maps are consistent with the data on human ***,the performance of the proposed framework is demonstrated via satisfactory classification results achieved with the Cohn-Kanade database,FG-NET FEED database, and Dartmouth database of children's faces.

关键词： facial expression recognition classification salient regions entropy brightness local binary pattern

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Electric-field induced fluctuations in laser generated plasma plume

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Plasma Science and Technology 2021年第4期23卷 83-89页

作者： rizwan ahmed Abdul JABBAR Zeshan Adeel UMAR Muhammad Aslam BAIG National Centre for Physics Quaid-i-Azam University Campus45320 IslamabadPakistan

The effect of an external electric field on laser-generated plasma has been *** is observed that the laser-generated plasma can be used for the ignition of a spark in the presence of a low voltage external electric *** eight-fold emission intensity enhancement in Cu I spectral lines are measured as compared to the signal intensity in the absence of an external electric *** plasma parameters remain the same initially,up to a few microseconds after the generation of plasma,and this feature makes it more interesting for the quantitative analysis of any sample using laser induced breakdown spectroscopy(LIBS).In the presence of an external electric field,fluctuations(contraction and expansion)in the laser-generated plasma are observed which increase the plasma decay time and consequently result in enhanced signal intensity.

关键词： LIBS laser produced plasma effect of external electric plasma parameters

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The Development Trends and Research Fronts in Orbital Angular Momentum Technology:A Bibliometric Analysis

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China Communications 2023年第2期20卷 289-310页

作者： Saleemullah memon Xiuping Li Kamran Ali memon Yuhan Huang Junaid ahmed Uqaili Muhammad Ishfaq School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Key Laboratory of Work Safety Intelligent Monitoring Beijing University of Posts and TelecommunicationsBeijing 100876China Department of Telecommunication Engineering Quaid-e-Awam University of EngineeringScience&TechnologyPakistan

Orbital angular momentum(OAM)technology,refers to Laguerre-Gaussian(LG)beams,twisted beams,vector/vortex beams,acoustic vortex beams and fractional vortex *** is an emerging and promising technology to improve the communication capacity,spectral efficiency,and anti-jamming capability due to its helical phase fronts and infinite orthogonal *** the OAM research began in the 1990s,the developing trends,current status,issues and characteristics through a systematic observation have not yet been *** paper presents a knowledge-based evolution of OAM research published in the Web of Science(WoS)from 2011 to 2021 using bibliometric analysis in *** results demonstrate that the bandwidth,efficiency,gain,divergence,phase quantization,bulky and complex feeding structures,misalignment,distortion,interferences atmospheric turbulence and diffraction were the key issues found in the OAM *** main research hotspots and categories,influential authors,leading journals,best institutions of OAM show a strong bias in favor of their functions and technology *** research on OAM was mainly performed by the counties that have developed the 5G and now moving towards 6G communications like China,USA and South *** study would serve as an inclusive guide on the future research trends and status especially for the OAM researchers.

关键词： orbital angular momentum(OAM) vortex beams bibliometric analysis CiteSpace

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Smart CardioWatch System for Patients with Cardiovascular Diseases Who Live Alone

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Computers, Materials & Continua 2021年第2期66卷 1237-1250页

作者： Raisa Nazir ahmed Kazi Manjur Kolhar Faiza rizwan College of Applied Medical Science Prince Sattam Bin Abdulaziz UniversityWadi Ad Dawaser11990Saudi Arabia Department Computer Science Prince Sattam Bin Abdulaziz UniversityWadi Ad Dawaser11990Saudi Arabia

The widespread use of smartwatches has increased their specific and complementary activities in the health sector for patient’s *** this study,we propose a framework referred to as smart forecasting CardioWatch(SCW)to measure the heart-rate variation(HRV)for patients with myocardial infarction(MI)who live alone or are outside their *** this study,HRV is used as a vital alarming sign for patients with *** performance of the proposed framework is measured using machine learning and deep learning techniques,namely,support vector machine,logistic regression,and decision-tree classification *** results indicated that the analysis of heart rate can help health services that are located remotely from the patient to render timely emergency health ***,taking more cardiac parameters into account can lead to more accurate *** the basis of our findings,we recommend the development of health-related software to aid researchers to develop frameworks,such as SCW,for effective provision of emergency health.

关键词： Forecasting system machine learning algorithms medical forecasting systems medical control systems supervised learning

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