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Heat transfer effectiveness characteristics maps for additively manufactured TPMS compact heat exchangers

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Energy Storage and Saving 2022年第3期1卷 153-161页

作者： Moza Alteneiji Mohamed I.Hassan ali kamran A.Khan Rashid K.Abu Al-Rub Advanced Digital&Additive Manufacturing Center United Arab Emirates Department of Mechanical Engineering Khalifa UniversityAbu DhabiUnited Arab Emirates Aerospace Engineering Department Khalifa UniversityAbu DhabiUnited Arab Emirates Mechanical Power Engineering Department Helwan UniversityCairoEgypt(on leave)

Increased power density in modern miniaturized electronics caused difficulty in keeping electronic performance *** challenge leads to the search for high-performance compact heat exchanger as one of the thermal management *** manufactured heat exchangers had limitations that thwart the develop-ment of geometrically complex heat exchangers which are capable of exploiting topological aspects to enhance thermal ***,additive manufacturing(AM)is proposed as a powerful fabrication tech-nique for compact heat exchanger based on the mathematically known triply periodic minimal surfaces(TPMS).In this work,we present 3D compact crossflow heat exchanger computational fluid dynamics(CFD)modelling of geometrically complex structures based on TPMS using STARCCM+CFD ***,CFD modelling is used to obtain new characteristics maps that relate heat transfer effectiveness(Ɛ)and number of transfer units for the proposed heat *** convection heat transfer coefficient,pressure drop,and inlet and outlet fluid temperature are all examined.

关键词： Compact crossflow heat exchanger(CCHE) Additive manufacturing(AM) Triply periodic minimal surface(TPMS) Effectiveness(Ɛ) Number of transfer units(NTU)

Role of interlayer composition in microstructure and mechanical properties during TLP bonding of GTD-111/IN-718 superalloys

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Transactions of Nonferrous Metals Society of China 2022年第3期32卷 908-926页

作者： ali IZADI GHAHFEROKHI Masoud KASIRI-ASGARANI kamran AMINI Mahdi RAFIEI Reza EBRAHIMI-KAHRIZSANGI Advanced Materials Research Center Department of Materials EngineeringNajafabad BranchIslamic Azad UniversityNajafabadIran Center for Advanced Engineering Research Majlesi BranchIslamic Azad UniversityIsfahanIran

An investigation was carried out to assess the applicability of transient liquid phase bonding of two dissimilar super-alloys with different interlayers. The effect of using three types of interlayer such as BNi-2, BNi-3, and BNi-9 on microstructure and mechanical properties was studied in the GTD-111/IN-718 system at 1100 ℃ for different bonding time. To determine the compositional changes and microstructure in the joint region, field emission scanning electron microscopy equipped with energy dispersive spectroscopy was utilized. The formation of Ni_(3)B in the athermally solidified zone(ASZ) is controlled by the B content and, accordingly, the morphology of Ni_(3)Si is governed by the Si content. The Cr content might impede the relocation of B from the interlayer into the base metal and the formation of CrB inside the ASZ is dominated by the Cr content. The high micro-hardness of the eutectic compounds is originated from the formation of boride matrixes such as Ni or Cr boride. The shear strength of the joint using BNi-9 after the completion of isothermal solidification is lower compared that that using BNi-3 and BNi-2, which could be related to the absence of Si in the filler metals constituent and the significant presence of Cr in BNi-9.

关键词： transient liquid phase bonding Ni-based superalloy isothermal solidification Ni-B compounds

A hybrid framework to analyze crisis management system maturity in sociotechnical systems

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Journal of Safety Science and Resilience 2022年第4期3卷 302-320页

作者： kamran Gholamizadeh Esmaeil Zarei Saman Poursiahbidi Omid Kalatpour Center of Excellence for Occupational health and research Center of Health SciencesHamadan University of Medical SciencesHamadan ***Iran Centre for Risk Integrityand Safety Engineering(C-RISE)Faculty of Engineering and Applied ScienceMemorial University of NewfoundlandNL A1B 3X5Canada HSE Management Department Occupational Health and Safety Research CenterHamadan University of Medical SciencesHamadan ***Iran

In recent decades,numerous catastrophic accidents have occurred worldwide,ranging from natural events(such as tsunamis,flooding,and earthquakes)to industrial events(such as mining and chemical process disasters).They endanger humans,the environment,organizations,and societies,as well as national ***,there have been few attempts to propose a model for assessing the required capabilities and potential challenges in crisis management system maturity(CMSM).Accordingly,this study proposes a framework for measuring CMSM levels in complex *** this end,a CMSM taxonomy was developed,including aspects,dimensions,and factors influencing the *** inference sets and fuzzy analytical hierarchy processes are then used for knowledge acquisition,quantification of the CMSM,and dealing with epistemic *** actual complex petrochemical plant is investigated to evaluate its *** findings revealed the most significant con-tributing factors:the CMSM’s current capability and challenges level(score),as well as the capacity to overcome the potential crisis response ***,the proposed model can be used as a practical approach for various chemical-processing plants.

关键词： Crisis management system maturity Crisis capabilities Crisis challenges Chemical process industries Fuzzy sets theory

Electromechanical Fields and Their Influence on the Internal Quantum Efficiency of GaN-Based Light-Emitting Diodes

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Acta Mechanica Solida Sinica 2018年第3期31卷 383-390页

作者： Muhammad Usman Kiran Saba Adnan Jahangir Muhammad kamran Nazeer Muhammad Department of Engineering Sciences Ghulam Ishaq Khan Institute of Engineering Sciences and Technology Swabi 23460 Pakistan Department of Mathematics COMSATS Institute of Information Technology Wah Cantt 47040 Pakistan Department of Electrical Engineering COMSATS Institute of Information Technology Wah Cantt 47040 Pakistan

The effect ofelectromechanical fields, i.e., polarization fields, on the efficiency droop of GaN-based light-emitting diodes is presented using both experimental and numerical analyses. The role of incorporating such polarization charge density in device performance is numerically investigated and further compared with the experimental results of internal quantum efficiency of three different devices in consideration.

关键词： Optoelectronic devices Photonic bandgap materials Visible and ultraviolet sources Light-emitting devices

A compliant polymorphing wing for small UAVs

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Chinese Journal of Aeronautics 2020年第10期33卷 2575-2588页

作者： Sadique P.MUHAMMED Rafic M.AJAJ kamran AKHAN Department of Mechanical Engineering United Arab Emirates UniversityAl Ain 15551United Arab Emirates Department of Aerospace Engineering Khalifa University of Science and TechnologyAbu Dhabi 127788United Arab Emirates

This paper presents the development of a novel compliant polymorphing wing capable of chord and camber morphing for small *** morphing wing can achieve up to 10%chord extension and±20°camber *** design,modeling,sizing,manufacturing and mechanical testing of the wing are *** polymorphing wing consists of one continuous front spar fixed to the fuselage and a rear spar on each side of the *** rear spar can translate in the chordwise direction(chord morphing)and rotate around itself(camber morphing).A flexible elastomeric latex sheet is used as the skin to cover the wing and maintain its aerodynamic shape whilst allowing *** loads from the skin are transferred to the spars using the compliant cellular ribs that support the flexible skin and facilitate ***-tensioning is applied to the skin to minimize wrinkling when subject to aerodynamic and actuation loads.A rack and pinion actuation system,powered by stepper motors,is used for ***-structural design,analysis and sizing are *** comparison between the polymorphing wing and the baseline wing(non-morphing)shows that chord morphing improves aerodynamic efficiency at low angles of attack while camber morphing improves efficiency at high angles of attack.

关键词： Camber morphing Chord morphing Compliant structures Flexible skin UAVs

Responses of jointed rock masses subjected to impact loading

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第4期10卷 624-634页

作者： Shabnam Aziznejad kamran Esmaieli John Hadjigeorgiou Denis Labrie Lassonde Institute of Mining University of Toronto CanmetMINING Natural Resources Canada

Impact-induced damage to jointed rock masses has important consequences in various mining and civil engineering applications. This paper reports a numerical investigation to address the responses of jointed rock masses subjected to impact loading. It also focuses on the static and dynamic properties of an intact rock derived from a series of laboratory tests on meta-sandstone samples from a quarry in Nova Scotia, Canada. A distinct element code(PFC2D) was used to generate a bonded particle model(BPM) to simulate both the static and dynamic properties of the intact rock. The calibrated BPM was then used to construct large-scale jointed rock mass samples by incorporating discrete joint networks of multiple joint intensities into the intact rock matrix represented by the BPM. Finally, the impact-induced damage inflicted by a rigid projectile particle on the jointed rock mass samples was determined through the use of the numerical model. The simulation results show that joints play an important role in the impactinduced rock mass damage where higher joint intensity results in more damage to the rock mass. This is mainly attributed to variations of stress wave propagation in jointed rock masses as compared to intact rock devoid of joints.

关键词： Jointed rock mass Impact loading Microcracks Rock damage

Ground movement patterns and shallow foundation performance in Iskenderun coastline during the 2023 Kahramanmaras earthquake sequence

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Earthquake Engineering and Engineering Vibration 2023年第4期22卷 867-881页

作者： Tugce Baser kamran Nawaz Albert Chung Seikh Faysal Ozgun Alp Numanoglu Department of Civil and Environmental Engineering University of Illinois Urbana-ChampaignUrbanaIllinois 61801USA Schnabel Engineering 16300 Christensen Rd Suite 350TukwilaWA 98188USA

This study focuses on the field reconnaissance efforts for investigating ground deformation behavior and building foundation performance in *** structures experienced significant damage or collapsed due to strong ground shaking in the coastal Iskenderun district of Hatay during the 2023 Kahramanmaras earthquake *** buildings were also impacted by ground failure due to liquefaction of deposits in the *** information regarding the general subsurface profile and post-earthquake data collected during the reconnaissance was used to perform simplified liquefaction and lateral spreading *** empirical methods provide first order estimations of settlements and lateral spreading but are not sufficient when the nature of the structure-soil-structure interaction and earthquake sequence is *** of vertical displacements and building tilt,liquefaction manifestations,and structural and foundation parameters potentially affecting foundation settlements including foundation geometry,building contact pressure,and building elastic period were used to evaluate seismic response of the ground and the structures through empirical *** of the buildings exhibited poor to mediocre foundation performance due to liquefaction-prone subsurface profiles,especially on the *** field and numerical research will reveal the cause of significant ground failure in the area as well as refined estimates for the seismic deformations.

关键词： Turkiye earthquake Iskenderun settlement geo-structures liquefaction lateral spreading foundation performance building settlements seismic settlements

Risk assessment in poplar plantations:a case study from northern Iran

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Journal of Forestry Research 2020年第4期31卷 1225-1233页

作者： Samaneh Namdari kamran Adeli Soleiman Mohammadi Limaei Zahra Bahramabadi Department of Forestry Agricultural and Natural Resources FacultyLorestan UniversityKhoramabadLorestan 68151-44316Iran Department of Forestry Faculty of Natural ResourcesUniversity of GuilanP.O.Box 1144Sowmeh SaraGuilanIran

Linear risk programming was used to determine the optimum cultivation pattern to increase incomes of poplar *** clones of Populus deltoides *** *** examined in Guilan province,northern *** and price data were taken from previous research at the Safrabaste Poplar Research Station and in interviews with *** Lingo software was used to analyze the data in different forms of *** results show that when risk was considered,the optimal solution included the clones Pd63/51-x1,-Pd72/51-x3,Pd73/51-x4 and Pd79/*** was a high growth fluctuations of the clones Pd69/55-x2,Pd77.51-x5,and Pd caroliniensis-x7 and were not included in cultivation ***,the existing farm plans executed by local farmers,is neither profitoriented nor efficient in terms of income risk management according to risk efficient *** results could help farmers with different levels of risk-aversion to select proper planting plans.

关键词： Populus deltoides Farmers Linear risk programming Optimum cultivation patterns

Malaria stratification in a malarious area,a field exercise

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Asian Pacific Journal of Tropical Medicine 2010年第10期3卷 807-811页

作者： Vatandoost Hassan Akbarzadeh kamran Hanafi- Bojd Ahniad ali Mashayekhi Minoo Saffari Mohammad Malik Elfatih M Kenyi Luka Abakar John Baptist Busaq alikhan Esmailpour Mohammad Hassen Abuelgasim Oshaghi Mohamad ali Department of Medical Entomology & Vector Control School of Public Health & National Institute of Health ResearchTehran University of Medical Sciences Kerman University of Medical Sciences PHC and Preventive Medicine Ministry of Health Baghlan province Urmieh University of Medical Sciences Northern State Ministry of Health Malaria Control Programme

Objective:To conducted a spatial analysis for stratification of priority malaria control areas in Kahnuj County,as part of field ***:Information of Health Centers of Kahnuj County has been used for stratification retrospectively.A knowledge,attitudes and practices(KAP) study was arranged to provide preliminary information about the knowledge,attitude and practice related to malaria in the ***:Numbers of malaria cases has been decreased in year *** were five important vectors of malaria in this region including:Anopheles stephensi (***),Anopheles dthali(***).Anopheles superpictus(***),Anophels culicifacies(***),and Anopheles Jluviatilis(***),but majority of malaria cases in this county was related to Plasmodium vivax(***).Educational levels of community were 38% ,20% ,10% and 32% for illiterate,primary,secondary and university levels,respectively. KAP study revealed that about 37% of people have got malaria at least once and only 27% of people knew that mosquito is the vector of ***:Malaria in Kahnuj represents a real *** occurs in city *** can be suspected for the first peak of malaria cases in late spring in Kahnuj *** has a relatively high density in autumn while two malaria cases due to *** were reported in *** on KAP study,the knowledge of respondents seems good but the attitude and practice is *** to the data such as API,main malaria vector,transmission rate,and foreign migrants,the Kahnuj County has been spatially divided into three strata based on various *** authorities should implement all the interventions based on stratification.

关键词： Malaria Kahnuj Stratification Iran