检索结果-南通市图书馆

Mixed convection in the heated semi-circular lid-driven cavity for non-Newtonian power-law fluids: Effect of presence and shape of the block

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2020年第5期28卷 1225-1240页

作者： Krunal M.Gangawane hakan f.oztop Department of Chemical Engineering National Institute of Technology RourkelaRourkela 769008OdishaIndia Department of Mechanical Engineering Engineering FacultyFirat UniversityElazig TR-23119Turkey

The present work delineates the hydrodynamics and thermal characteristics due to mixed convection in the liddriven semi-circular cavity affected by the presence of the adiabatic block at its geometric center for twodimensional,steady-state,laminar and for non-Newtonian power-law *** semi-circular cavity has a diameter of *** horizontal wall/lid is sliding with a uniform horizontal velocity(u=U)and is subjugated to the ambient thermal condition;while the curved surface is subjugated to a higher isothermal *** convective characteristics inside the system is explored for the broad range of Richardson number(0.1≤Ri≤10),Prandtl number(1≤Pr≤100)and non-Newtonian power-law index(0.5≤n≤1.5)at a constant Grashof number of 10~*** from this,the effect of shape(cross-section)of the inserted block,i.e.,circular,square and triangular on heat transfer characteristics has also been *** is observed that the shear thickening fluids display better cooling ***,the cavity with immersed triangular block shows better heat transfer results than the circular and square *** deviations observed in the flow and heat transfer characteristics in the cavity by inserting an adiabatic block as compared with cavity without block have been ascertained by calculating normalized Nusselt number(Nu^N).The presence of the block was found to have a diminishing effect on the heat transfer due to convection in the *** the end,the results of the study are summarized in the form of a predictive correlation exhibiting the functional dependence of average Nusselt number with Prandtl number,power-law index,and Richardson number.

关键词： Heat transfer enhancement Semi-circular cavity Adiabatic block Non-Newtonian fluids

维普期刊数据库

Acoustical imaging of the nearshore seafloor depositions and deformations,a key study for Western Istanbul,Türkiye

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2024年第8期43卷 69-78页

作者： ÖZGAN Sinan ALP hakan BAYAT Oğuz VARDAR Denizhan Institute of Marine Sciences and Management Istanbul University34134 VefaIstanbulTürkiye Department of Geophysical Engineering Istanbul University Cerrahpaşa34500 HadımköyIstanbulTürkiye School of Engineering and Architecture Altinbas University34217 BagcilarIstanbulTürkiye

To protect the sustainability of the benefits from seas and near coastal areas,which have under the effect of the very complex hydrodynamic conditions and intensive human activities,without disrupting the balance of nature,it is necessary to image the status of the seafloor ***,this study presents the deformations,depositional conditions,underwater constructions,and the other non-natural impacts on the seafloor of the nearshore area at western Istanbul(between Küçükçekmece and Büyükçekmece lagoons)where it intensely used by the *** results of the study may provide some guidance for understanding the impacts and risk factors of uses that are or will be conducted in coastal and/or near-coastal *** planning for civil coastal structures and areas should be done in great harmony with nature,minimizing negative environmental *** sediment distribution in the area is generally quite complex,the current state of the region,wave action,hydrodynamic conditions,the amount of material transported from the land,and bathymetry are important influencing *** seafloor has been damaged primarily by anchor deformation and associated bottom scanning,as well as disturbing trawl *** seafloor was observed as partially shallowing near the constructions(such as natural gas pipelines,fishermen’s shelter,and port piles)of coastal areas and associated with sand ***,scanning the seafloor using side-scan sonar may provide valuable frequency data to prevent future disruptions.

关键词： port activities sediment classifications side scan sonar sub bottom profiler coastal protection

Comparison of Type I Error Rates of Siegel-Tukey and Savage Tests among Non-Parametric Tests

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Applied Sciences 2024年第9期14卷 2393-2410页

作者： Sahib Ramazanov hakan Çora Department of Business Administration Graduate Education Institute Karabk University Karabk Trkiye Department of International Relations Faculty of Business and Management Sciences Istanbul Okan University Istanbul Trkiye

This study aimed to examine the performance of the Siegel-Tukey and Savage tests on data sets with heterogeneous variances. The analysis, considering Normal, Platykurtic, and Skewed distributions and a standard deviation ratio of 1, was conducted for both small and large sample sizes. for small sample sizes, two main categories were established: equal and different sample sizes. Analyses were performed using Monte Carlo simulations with 20,000 repetitions for each scenario, and the simulations were evaluated using SAS software. for small sample sizes, the I. type error rate of the Siegel-Tukey test generally ranged from 0.045 to 0.055, while the I. type error rate of the Savage test was observed to range from 0.016 to 0.041. Similar trends were observed for Platykurtic and Skewed distributions. In scenarios with different sample sizes, the Savage test generally exhibited lower I. type error rates. for large sample sizes, two main categories were established: equal and different sample sizes. for large sample sizes, the I. type error rate of the Siegel-Tukey test ranged from 0.047 to 0.052, while the I. type error rate of the Savage test ranged from 0.043 to 0.051. In cases of equal sample sizes, both tests generally had lower error rates, with the Savage test providing more consistent results for large sample sizes. In conclusion, it was determined that the Savage test provides lower I. type error rates for small sample sizes and that both tests have similar error rates for large sample sizes. These findings suggest that the Savage test could be a more reliable option when analyzing variance differences.

关键词： Non-Parametric Test Siegel-Tukey Test Savage Test Monte Carlo Simulation Type I Error

Effect of Ozone Treatment on Microbiological Properties of Stored Wheat

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

food and Nutrition Sciences 2024年第2期15卷 140-150页

作者： Hussein Al-Sahho hakan Kuleaşan Department of food Engineering Suleyman Demirel University Isparta Türkiye

In this study, ozone gas was applied to samples of durum wheat stored in four experimental groups (durum wheat without any treatment for comparison, durum wheat treated with ozone, purified durum wheat, and purified durum wheat treated with ozone). Two groups were treated with ozone gas at 3 ppm concentration for 1 hour. Groups were then placed in air-tight glass jars and stored for 6 months at variable temperatures between 24.7°C to 34.8°C. Microbiological (total count bacteria, yeast/molds and coliform) and physical properties (moisture, color and ash) evaluated. Ozone application statistically caused a significant reduction in the numbers of bacteria, yeast, molds and coliforms. Ozone application, washing process and storage temperature are the major factors affecting the microbial counts. No significant differences were determined in moisture and ash contents of samples after ozone treatment. The color measurement results showed that color values of wheat samples were affected by ozone treatment, storage and washing.

关键词： Wheat Storage Ozone Application Wheat Impurities Microbial Enumeration

How has the COVID-19 pandemic changed treatment preferences of patients with proximal ureteral stones?

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Comparison of purification processes of natural gas obtained from three different regions in the world

当代泌尿学（英文） 2024年第1期18卷 66-70页

作者： Ali Kaan Yildiz Ahmet Varan hakan Kurt Omer Gokhan Doluoglu Berat Cem Ozgur Department of Urology University of Medical SciencesAnkara Training and Research HospitalAnkaraTurkey

Background:The impact of the coronavirus disease 2019(COVID-19)pandemic on patient decision making remains *** study aimed to investigate the effect of the pandemic on treatment preferences of patients with proximal ureteral stones.Materials and methods:Retrospective data regarding treatment preferences of patients diagnosed with symptomatic proximal ure-teral stones between July 2018 and November 2021 at a single center were *** from 493 patients were analyzed according to 2 groups,including patients diagnosed during the COVID-19 pandemic and those diagnosed during an equivalent period of time be-fore the pandemic.Results:Preference for conservative treatment increased during the COVID-19 pandemic(p=0.009).In patients who had previously undergone shock wave lithotripsy(SWL),the preference for SWL decreased and the preference for conservative treatment increased during the COVID-19 pandemic(p=0.042).Multiple logistic regression analysis revealed a significant correlation between a preference for conservative treatment during the pandemic and no prior spontaneous stone passage(p=0.003;odds ratio[OR],2.48;95％con-fidence interval[CI],1.45-4.23),no hydronephrosis(p=0.035;OR,3.57;95％Cl,1.34-9.49),and a visual analog scale score of 4 or less(p=0.018;OR,1.97;95％Cl,1.15-3.38).Conclusions:A significant increase in the preference for conservative treatment was observed among patients diagnosed during the pandemic,and patients with a history of SWL demonstrated a preference shift from SWL to conservative treatment.

关键词： COVID-19 pandemic Treatment preference Ureter Urolithiasis

来源：评论

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2012年第1期21卷 61-68页

作者： Tansel Koyun Mehmet Kunduz hakan f. oztop Ibrahim Ucgul Department of Mechanical Engineering Suleyman Demirel University Department of Mechanical Engineering Technology Faculty Fιrat University Deparment of Mechanical Engineering College of Engineering King Saud University Department of Textile Engineering Suleyman Demirel University

Natural gases obtained from different regions in the world as Scholen-Germany, Saudi Arabia and Iran were purified with a package code and the obtained results were compared in this study. for purification process, both natural gases flowing in a vertical pipe and monoethanolamine （MEA） flowing as a film from the internal surface of a pipe were examined together. Both fluids were flown in a vertical and laminar regime. Binary diffusion coefficients, Schmidt numbers （Sc） and dynamical viscosities were calculated individually for three types of natural gases. It is demonstrated that the chemical absorption method by MEA process is the most appropriate method at high DamkOhler （Da） numbers particularly for natural gases containing high concentrations of CO2 and H2S.

关键词： natural gas purification monoethanolamine (MEA)

维普期刊数据库

Natural convective heat transfer and nanofluid flow in a cavity with top wavywall and corner heater

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2016年第5期28卷 873-885页

作者： Mikhail A. SHEREMET Ioan POP hakan f. oztop Nidal ABU-HAMDEH Department of Theoretical Mechanics Tomsk State University Tomsk Russia Department of Nuclear and Thermal Power Plants Tomsk Polytechnic University Tomsk Russia Department of Applied Mathematics BabesBolyai University Cluj-Napoca Romania Department of Mechanical Engineering Technology Faculty Flrat University Elazig Turkey Mechanical Engineering Department Faculty of Engineering King Abdulaziz University Jeddah Saudi Arabia

A numerical analysis of natural convection of nanofluid in a wavy-walled enclosure with an isothermal comer heater has been carried out. The cavity is heated from the left bottom comer and cooled from the top wavy wall while the rest walls are adiaba- tic. Mathematical model has been formulated using the single-phase nanofluid approach. Main efforts have been focused on the effects of the dimensionless time, Rayleigh number, undulation number, nanoparticle volume fraction and length of comer heaters on the fluid flow and heat transfer inside the cavity. Numerical results have been presented in the form of streamlines, isotherms, velocity and temperature profiles, local and average Nusselt numbers. It has been found that nanoparticle volume fraction essentially affects both fluid flow and heat transfer while undulation number changes significantly only the heat transfer rate.

关键词： wavy cavity natural convection nanofluid comer heater numerical results

维普期刊数据库

位于三角形通风腔内的圆形多孔潮湿介质的传热和传质（英文）

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2024年第6期 1956-1972页

作者： SEL?MEfEND?G?L fatih ?ZCAN ?OBAN Seda ?ZTOP hakan f Department of Mechanical Engineering College of Engineering King Faisal University Department of Mechanical Engineering Manisa Celal Bayar University Department of Mechanical Engineering Technology Faculty F?rat University

采用有限元方法研究了圆形多孔湿介质在二维三角形腔内的传热传质问题。所研究的多孔介质是一个潮湿的食品样品，位于配置不同位置的进口和出口的腔体的中间。对不同雷诺数(Re 50～250)、干风入口温度(40～80℃)和不同端口位置的对流干... 详细信息

采用有限元方法研究了圆形多孔湿介质在二维三角形腔内的传热传质问题。所研究的多孔介质是一个潮湿的食品样品，位于配置不同位置的进口和出口的腔体的中间。对不同雷诺数(Re 50～250)、干风入口温度(40～80℃)和不同端口位置的对流干燥性能进行了数值模拟评价。结果表明，改变孔位对三角腔内的再循环有显著影响，对流干燥性能受到较大影响。随着时间的延长和雷诺数的增加，含水率减少。进口和出口端口位于壁面中间的P4情况具有最好的干燥性能，最差的情况是进口和出口更靠近腔室的角落P1情况。在Re=250、T=80℃、t=120 min时，两种材料的减湿量相差192%。

关键词：对流干燥多孔区域空腔流进/出口有限元方法

Role of biomarkers in community-acquired pneumonia management

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Acute Disease 2024年第3期13卷 87-92页

作者： Bahaeddin Onur hakan BarışDemirbas Arif Gulmez Department of Emergency Medicine Istanbul Health and Technology UniversityIstanbulTurkey Department of Emergency PHCCAl Karaana Health CenterDohaQatar Department of Emergency PHCCUmm Slala Health CenterDohaQatar Department of family Medicine PHCCAl Thumama Health CenterDohaQatar

Community-acquired pneumonia(CAP)poses a significant global health threat,particularly affecting vulnerable *** and scoring systems play a crucial role in diagnosing,assessing severity,and guiding treatment decisions for CAP *** like C reactive protein,procalcitonin,and the neutrophil-to-lymphocyte ratio aid in diagnosis and severity assessment,while scoring systems such as CURB-65 and Pneumonia Severity Index classify patients into risk *** biomarkers(uremia,elevated respiratory rate,hypotension,and age≥65)like serum amyloid A and S100 proteins show promise in predicting disease severity and ***,further research is needed to determine their precise roles and clinical utility in CAP management.

关键词： CURB-65 Community-acquired pneumonia Procalcitonin Alpha-1 antitrypsin Serum amyloid A