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Modeling of Heat Transfer and Steam Condensation Inside a Horizontal Flattened Tube

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Fluid Dynamics & Materials Processing 2022年第4期18卷 985-998页

作者： M.Gh.Mohammed kamil M.S.Kassim r.A.Mahmood L.AZ Mahdi Mechanical Engineering Department Faculty of EngineeringMustansiriyah UniversityBaghdad10052Iraq School of Mechanical and Electrical Engineering University of Southern QueenslandQueensland4350Australia Engineering Collage University of ZakhoZakho42002Iraq Energy and renewable Energies Technology Center University of TechnologyBaghdad10066Iraq

This work investigates the steam condensation phenomena in an air-cooled *** considered horizontal flattened tube has a 30 mm hydraulic diameter,and its length is a function of the steam quality with a limit value between 0.95 and *** mass flow rate ranges from 4 to 40 kg/m^(2).s with a saturated temperature spanning an interval from 40°C to 80°C.A special approach has been implemented using the Engineering Equation Solver(EES)to solve a series of equations for the two-phase flow pattern and the related heat transfer coefficients.A wavy-stratified structure of the two-phase flow has been found when the mass rate was between 4 and 24 kg/m^(2).*** contrast,an initially annular flow is gradually converted into a wavy stratified flow(due to the condensation process taking place inside the flattened tube)when the considered range ranges from 32 to 40 kg/m^(2).s.

关键词： Condensation flow pattern structure heat transfer rate flow in horizontal pipe flow behaviour EES modelling

Comparative study of natural chemical for enhanced oil recovery: Focus on extraction and adsorption at quartz sand surface

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Petroleum 2023年第1期9卷 83-93页

作者： Azza Hashim Abbas ramzi A.Abd Alsaheb Jaafar kamil Abdullah School of Mining and Geosciences Nazarbayev UniversityKazakhstan Al-khwarizmi College of Engineering University of BaghdadIraq Basrah University College of Science and Technology Iraq

In chemical enhanced oil recovery(CEOr),it is very important to utilize the excessive usage of chemicals.A great opportunity lies in adopting natural surfactants,since it is cheaper,ecosystem friendly,and less toxic than their counterpart synthetic *** the availability of natural surfactant sources,it is yet very early to decide on their ***,this research focuses on natural-saponin extracted from different raw materials available in the Middle East and their interaction with quartz-sand.A special focus was given to the adsorption isotherm models to describe the interaction with the reservoir *** raw materials were investigated are fenugreek,sugar beet leaves and *** main extraction method employed was the chemical extraction using the *** study used Uv–vis spectrometer to investigate the micellization behaviour and the consequent adsorption on *** presence of triterpenoid saponin is found dominant in all the sample,the intensity and purity differed according to the raw material *** critical micelle concentration(CMC)was at a close range of 4–5.5 wt%in all the *** highest adsorption was obtained by sugar beet leaves which is 192 g/*** is 25%and 37%higher than the Fenugreek and chickpeas,*** the salinity resulted in adsorption reduction between 2%and 56%.For the adsorption isotherms,it showed good agreement with the Langmuir model *** remarkable finding is that the sugar beet leaves heterogeneous model seems to be valid by Frendluich and Halsey isotherms.

关键词： Natural surfactants Quartz Adsorption isotherm Salinity Fenugreek Sugar beet leaves Chickpeas

Comparative Evaluation and Comprehensive Analysis of Machine Learning Models for regression Problems

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Data Intelligence 2022年第3期4卷 620-652页

作者： Boran Sekeroglu Yoney Kirsal Ever kamil Dimililer Fadi Al-Turjman Information Systems Engineering Department Near East UniversityNicosiaCyprusMersin 10Turkey Software Engineering Department Near East UniversityNicosiaCyprusMersin 10Turkey Electrical and Electronic Engineering Department Near East UniversityNicosiaCyprusMersin 10Turkey Artificial Intelligence Engineering Department Near East UniversityNicosiaCyprusMersin 10Turkey research Centre for AI and IoT Near East UniversityNicosiaCyprusMersin 10Turkey

Artificial intelligence and machine learning applications are of significant importance almost in every field of human life to solve problems or support human experts. However, the determination of the machine learning model to achieve a superior result for a particular problem within the wide real-life application areas is still a challenging task for researchers. The success of a model could be affected by several factors such as dataset characteristics, training strategy and model responses. Therefore, a comprehensive analysis is required to determine model ability and the efficiency of the considered strategies. This study implemented ten benchmark machine learning models on seventeen varied datasets. Experiments are performed using four different training strategies 60:40, 70:30, and 80:20 hold-out and five-fold cross-validation techniques. We used three evaluation metrics to evaluate the experimental results: mean squared error, mean absolute error, and coefficient of determination(r2score). The considered models are analyzed, and each model’s advantages, disadvantages, and data dependencies are indicated. As a result of performed excess number of experiments, the deep Long-Short Term Memory(LSTM) neural network outperformed other considered models, namely, decision tree, linear regression, support vector regression with a linear and radial basis function kernels, random forest, gradient boosting, extreme gradient boosting, shallow neural network, and deep neural network. It has also been shown that cross-validation has a tremendous impact on the results of the experiments and should be considered for the model evaluation in regression studies where data mining or selection is not performed.

关键词： Machine learning regression Comparative evaluation Analysis Validation

Annual and seasonal changes of the air temperature with altitude in the Upper Dades valley, High Atlas, Morocco

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Journal of Mountain Science 2022年第1期19卷 85-102页

作者： ŻMUDZKA Elwira DŁUŻEWSKI Maciej DĄBSKI Maciej LEZIAK kamil rOJAN Elżbieta Department of Climatology Faculty of Geography and Regional StudiesUniversity of WarsawKrakowskie Przedmieście 3000-927 WarsawPoland Department of Geomorphology Faculty of Geography and Regional StudiesUniversity of WarsawKrakowskie Przedmieście 3000-927 WarsawPoland

The purpose of this study is to determine the size of air temperature changes with altitude in the mountains of the arid zone, on the example of the Upper Dades valley(High Atlas, Morocco). The air temperature change with altitude was determined on the basis of 5 years data from three meteorological stations. The analysis was carried out on an annual and seasonal basis. The annual and daily variations of thermal gradients between pairs of stations were also determined. It was found that the average thermal gradient in the Upper Dades valley was-1.02℃ per 100 m. The highest values of the thermal gradient occur in winter and the lowest in summer. In winter,the thermal gradient was characterized by the greatest variability. Minima of the daily variation of air temperature gradients were observed in early morning hours and maxima around midday. In the lower part of the valley, air temperature inversion frequently developed between 10 AM and 3 PM *** obtained results show high thermal gradients in the mountains of the arid zone, with their annual amplitude increasing in the lower parts of the *** instantaneous values of the gradients were significantly modified by the supply of latent heat and the occurrence of dust storms. It has been shown that the advection factor plays an important role in shaping large gradient values. The study contains novel results of thermal gradient measurements in high mountains of arid zone.

关键词： Air temperature gradient Thermal inversion Annual and seasonal variability Synoptic situation High mountains of arid zone High Atlas Mountains

X-ray Image-Based COVID-19 Patient Detection Using Machine Learning-Based Techniques

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Computer Systems Science & Engineering 2022年第11期43卷 671-682页

作者： Shabana Habib Saleh Alyahya Aizaz Ahmed Muhammad Islam Sheroz Khan Ishrat Khan Muhammad kamil Department of Information Technology College of ComputerQassim UniversityBuraidah52571Saudi Arabia Department of Electrical Engineering College of Engineering&Information TechnologyOnaizah CollegesOnaizah51911Saudi Arabia Digital Image Processing Lab Islamia CollegePeshawar25120KPKPakistan Department of Computer Science College of Computer and Information SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Electrical Engineering National University of Computer and Emerging SciencesPeshawarPakistan

In early December 2019,the city of Wuhan,China,reported an outbreak of coronavirus disease(COVID-19),caused by a novel severe acute respiratory syndrome coronavirus-2(SArS-CoV-2).On January 30,2020,the World Health Organization(WHO)declared the outbreak a global pandemic *** the face of the COVID-19 pandemic,the most important step has been the effective diagnosis and monitoring of infected *** COVID-19 using Machine Learning(ML)technologies can help the health care unit through assistive diagnostic suggestions,which can reduce the health unit's burden to a certain *** paper investigates the possibilities of ML techniques in identifying/detecting COVID-19 patients including both conventional and exploring from chest X-ray images the effect of viral *** approach includes preprocessing,feature extraction,and ***,the features are extracted using the Histogram of Oriented(HOG)and Local Binary Pattern(LBP)feature ***,for the extracted features classification,six ML models of Support Vector Machine(SVM)and K-Nearest Neighbor(KNN)is *** results show that the diagnostic accuracy of random forest classifier(rFC)on extracted HOG plusLBP features is as high as 94%followed by SVM at 93%.The sensitivity of the K-nearest neighbour model has reached an accuracy of 88%.Overall,the predicted approach has shown higher classification accuracy and effective diagnostic *** is a highly useful tool for clinical practitioners and radiologists to help them in diagnosing and tracking the cases of COVID-19.

关键词： Image pre-processing detection classification x-ray images filter

MicrorNA regulates the toxicological mechanism of four mycotoxins in vivo and in vitro

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Journal of Animal Science and Biotechnology 2022年第4期13卷 923-934页

作者： Jia Chen Shuhua Yang Peng Li Aibo Wu Eugenie Nepovimova Miao Long Wenda Wu kamil Kuca College of Animal Science&Veterinary Medicine Shenyang Agricultural UniversityShenyang 110866China SIBS-UGENT-SJTU Joint Laboratory of Mycotoxin research CAS Key Laboratory of NutritionMetabolism and Food SafetyShanghai Institute of Nutrition and HealthUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200031China Department of Chemistry Faculty of ScienceUniversity of Hradec KraloveHradec Kralove 50003Czech Republic MOE Joint International research Laboratory of Animal Health and Food Safety College of Veterinary MedicineNanjing Agricultural UniversityNanjing 210095China Biomedical research Center University Hospital Hradec KraloveHradec Kralove 50003Czech Republic.

Mycotoxins can cause body poisoning and induce carcinogenesis,often with a high mortality ***,it is of great significance to seek new targets that indicate mycotoxin activity and to diagnose and intervene in mycotoxin-induced diseases in their early ***(mirNAs)are physiological regulators whose dysregulation is closely related to the development of *** are thus important markers for the occurrence and development of *** this review,consideration is given to the toxicological mechanisms associated with four major mycotoxins(ochratoxin A,aflatoxin B1,deoxynivalenol,and zearalenone).The roles that mirNAs play in these mechanisms and the interactions between them and their target genes are explained,and summarize the important role of histone modifications in their *** a result,the ways that mirNAs are regulated in the pathogenicity signaling pathways are revealed which highlights the roles played by mirNAs in preventing and controlling the harmful effects of the *** is hoped that this review will provide a theoretical basis for the prevention and control of the damage caused by these mycotoxins.

关键词： Histone Methylation MicrorNA Mycotoxin

On ASGS framework:general requirements and an example of implementation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 511-521页

作者： KULESZA kamil KOTULSKI Zbigniew Department of Applied Mathematics and Theoretical Physics University of CambridgeCambridge CB3 0WAUK Institute of Fundamental Technological ResearchPolish Academy of SciencesWarsaw 00-049Poland Institute of Fundamental Technological research Polish Academy of SciencesWarsaw 00-049Poland

In the paper we propose a general, abstract framework for Automatic Secret Generation and Sharing (ASGS) that should be independent of underlying Secret Sharing Scheme (SSS). ASGS allows to prevent the Dealer from knowing the secret. The Basic Property Conjecture (BPC) forms the base of the framework. Due to the level of abstraction, results are portable into the realm of quantum computing. Two situations are discussed. First concerns simultaneous generation and sharing of the random, prior nonexistent secret. Such a secret remains unknown until it is reconstructed. Next, we propose the framework for automatic sharing of a known secret. In this case the Dealer does not know the secret and the secret Owner does not know the shares. We present opportunities for joining ASGS with other extended capabilities, with special emphasis on PVSS and pre-positioned secret sharing. Finally, we illustrate framework with practical implementation.

关键词：密钥共享方案 ASGS 安全协议基本要求实现认证管理

Development of anti-corrosive coating on AZ31 Mg alloy subjected to plasma electrolytic oxidation at sub-zero temperature

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Journal of Magnesium and Alloys 2022年第7期10卷 1915-1929页

作者： S.Fatimah M.P.kamil D.I.Han W.Al-Zoubi Y.G.Ko Materials Electrochemistry Group School of Materials Science and EngineeringYeungnam UniversityGyeongsan 38541Republic of Korea

Plasma electrolytic oxidation(PEO)is a promising surface treatment to generate adherent and thick anti-corrosive coating on light-weight metals(Al,Mg,Ti,etc.)using an eco-friendly alkaline *** energy plasma,however,inevitably generates porous structures that limit their practical *** present study proposes a straight-forward simple method by utilizing sub-zero electrolyte(268 K)to alter the plasma characteristics during formation of the protective coating on AZ31 Mg alloy via PEO with a comparison to the electrolyte at room temperature(298 K).In refrigerated electrolyte,the formation of micro-defects is suppressed relatively at the expense of low coating growth,which is measured to be twice lower than that at 298 K due to the temperature-dependent soft plasma discharges contributing to the development of the present *** a consequence,corrosion resistance of the sample processed at 268 K is superior to that of 298K,implying that the effect of coating thickness is less dominant than that of *** phenomenon is interpreted in relation to the ionic movement and oxide solidification controlled by soft plasma discharges arising from the temperature gradient between electrolyte and surface of the substrate during PEO.

关键词： AZ31 Mg alloy Plasma electrolytic oxidation Sub-zero electrolyte Anti-corrosive coating Corrosion

Thermal Energy Storage Characteristics of Myristic and Stearic Acids Eutectic Mixture for Low Temperature Heating Applications

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Chinese Journal of Chemical Engineering 2006年第2期14卷 270-275页

作者： Ahmet Sari kamil Kaygusuz Department of Chemistry Gaziosmanpasa University 60240 Tokat Turkey Department of Chemistry Karadeniz Technical University 61100 Trabzon Turkey

Stearic acid (67.83℃) and myristic acid (52.32℃) have high melting temperatures that can limit their use as phase change material (PCM) in low temperature solar heating applications such as solar space and greenhouse heating in regard to climatic requirements. However, their melting temperatures can be adjusted to a suitable value by preparing a eutectic mixture of the myristic acid (MA) and the stearic acid (SA). In the present study, the thermal analysis based on differential scanning calorimetry (DSC) technique shows that the mixture of myristic acid (MA) and stearic acid (SA) in the respective composition (by mass) of 64% and 36% forms a eutectic mixture having melting temperature of 44.13℃ and the latent heat of fusion of 182.4J·g-1. The thermal energy storage characteristics of the MA-SA eutectic mixture filled in the annulus of two concentric pipes were also experimentally established. The heat recovery rate and heat charging/discharging fractions were determined with respect to the change in the mass flow rate and the inlet temperature of heat transfer fluid. Based on the results obtained by DSC analysis and by the heat charg- ing/discharging processes of the PCM, it can be concluded that the MA-SA eutectic mixture is a potential material for low temperature thermal energy storage applications in terms of its thermo-physical and thermal characteristics.

关键词：低温加热肉豆蔻酸硬脂酸共熔混合物储热特性差示扫描量热法