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Journal of Iron and Steel Research International 2011年第8期18卷 65-72页

作者： Fatih hayat hüseyin uzun Metallurgy and Materials Engineering Department Engineering FacultyKarabuk University Metallurgy Education Department Technical Education FacultySakarya University

Grade A （GA） and high strength steel Dh36 ship steels possessing different chemical compositions were used, and strength properties of GA steel and Dh36 steel were compared. Additionally, 4 types of dual phase （DP） steels with different martensite volume fractions （MVFs） were produced from GA steel by means of heat treatment and they were compared with other steels through conducting mierostructure, microhardness, tensile and impact tests. The fracture surfaces of specimens （Dh36, GA and DP steels） exposed to tensile and Charpy impact tests were investigated by scanning electron microscope. Furthermore, it was found that the specimens quenched from 800 and 900℃ had better strength than Dh36 steel. The tensile test results indicated that the tensile strength of DP steel water quenched from 900℃ was 3 times that of GA steel and twice that of Dh36 steel.

关键词： Grade A ship steel Dh36 ship steel dual phase steel martensite mechanical property fracture

Influence of Confined Concrete Models on the Seismic Response of RC Frames

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Structural Durability & health Monitoring 2024年第3期18卷 197-222页

作者： hüseyin Bilgin Bredli Plaku Department of Civil Engineering EPOKA UniversityTirana1039Albania

In this study, the influence of confined concrete models on the response of reinforced concrete structures is investigatedat member and global system levels. The commonly encountered concrete models such as Modified Kent-Park, Saatçioğlu-Razvi, and Mander are considered. Two moment-resisting frames designed according to thepre-modern code are taken into consideration to reflect the example of an RC moment-resisting frame in thecurrent building stock. The building is in an earthquake-prone zone located on Z3 Soil Type. The inelasticresponse of the building frame is modelled by considering the plastic hinges formed on each beam and columnelement for different concrete classes and stirrups spacings. The models are subjected to non-linear static *** differences between confined concrete models are comparatively investigated at both reinforced concretemember and system levels. Based on the results of the comparative analysis, it is revealed that the column behaviouris mostly influenced by the choice of model, due to axial loads and confinement effects, while the beams areless affected, and also it is observed that the differences exhibited in the moment-curvature response of columncross-sections do not significantly affect the overall behaviour of the global system. This highlights the critical roleof model selection relative to the concrete strength and stirrup spacing of the member.

关键词： Non-linear static analysis moment-curvature relationships plastic hinges concrete confinement models seismic action

Correlation of work function and stacking fault energy through Kelvin probe force microscopy and nanohardness in diluteα-magnesium

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Journal of Magnesium and Alloys 2024年第1期12卷 237-250页

作者： Yigit Türe Ali Arslan Kaya hüseyin Aydin Jiang Peng Servet Turan Eskisehir Technical University Porsuk Vocational SchoolElectronics and Automation DepartmentProgram of MechatronicsEskisehirTurkey Mugla Sitki Kocman University Engineering FacultyMetallurgy and Materials Engineering DepartmentMuglaTurkey hüseying Aydın TUBITAK MRCTurkey Jiang Peng Chongqing UniversityChina Eskisehir Technical University Engineering FacultyMaterials Science and Engineering DepartmentEskisehirTurkey

Electronic interactions of the Group 2A elements with magnesium have been studied through the dilute solid solutions in binary Mg-Ca,Mg-Sr and Mg-Ba *** investigation incorporated the difference in the‘Work Function'(ΔWF)measured via Kelvin Probe Force Microscopy(KPFM),as a property directly affected by interatomic bond types,*** electronic structure,nanoindentation measurements,and Stacking Fault Energy values reported in the *** was shown that the nano-hardness of the solid-solutionα-Mg phase changed in the order of Mg-Ca>Mg-Sr>***,it was shown,by also considering the nano-hardness levels,that SFE of a solid-solution is closely correlated with its‘Work Function'***-hardness measurements on the eutectics andΔWF difference between eutectic phases enabled an assessment of the relative bond strength and the pertinent electronic structures of the eutectics in the three *** withΔWF and at least qualitative verification of those computed SFE values with some experimental measurement techniques were considered important as those computational methods are based on zero Kelvin degree,relatively simple atomic models and a number of *** asserted by this investigation,if the results of measurement techniques can be qualitatively correlated with those of the computational methods,it can be possible to evaluate the electronic structures in alloys,starting from binary systems,going to ternary and then multi-elemental *** investigation has shown that such a qualitative correlation is *** all,the SFE values are not treated as absolute values but rather become essential in comparative investigations when assessing the influences of alloying elements at a fundamental level,that is,free electron density *** study indicated that the principles of‘electronic metallurgy'in developing multi-elemental alloy systems can be followed via practical experimental methods,i.e.ΔWF measurements using KPF

关键词： Mg alloys Dilute alloys Work function Stacking fault energy Kelvin probe force microscopy Short range order Miedema Nanoindentation Eutectics

Red cell distribution width-to-albumin ratio is a simple promising prognostic marker in acute cholangitis requiring biliary drainage

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hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 487-494页

作者： Fatih Acehan hüseyin Camli Cagdas Kalkan Mesut Tez Burak Furkan Demir Emin Altiparmak Ihsan Ates Department of Internal Medicine Ankara City HospitalAnkara 06800Türkiye Department of Gastroenterology Ankara City HospitalAnkara 06800Türkiye Department of General Surgery Ankara City HospitalAnkara 06800Türkiye

Background: It is crucial to assess the severity of acute cholangitis(AC). There are currently several prognostic markers. however, the accuracies of these markers are not satisfied. The present study aimed to investigate the predictive value of the red cell distribution width(RDW)-to-albumin ratio(RAR) for the prognosis of AC. Methods: We retrospectively evaluated consecutive patients diagnosed with AC between May 2019 and March 2022. RAR was calculated, and its predictive ability for in-hospital mortality, intensive care unit(ICU) admission, bacteremia, and the length of hospitalization were analyzed. Results: Out of 438 patients, 34(7.8%) died. Multivariate analysis showed that malignant etiology [odds ratio(OR) = 4.816, 95% confidence interval(CI): 1.936-11.980], creatinine(OR = 1.649, 95% CI: 1.095-2.484), and RAR(OR = 2.064, 95% CI: 1.494-2.851) were independent risk factors for mortality. When adjusted for relevant covariates, including age, sex, malignant etiology, Tokyo severity grading(TSG), Charlson comorbidity index, and creatinine, RAR significantly predicted mortality(adjusted OR = 1.833, 95% CI: 1.280-2.624). When the cut-off of RAR was set to 3.8, its sensitivity and specificity for mortality were 94.1% and 56.7%, respectively. Patients with an RAR of > 3.8 had a 20.9-fold(OR = 20.9, 95% CI: 4.9-88.6) greater risk of mortality than the remaining patients. The area under the curve value of RAR for mortality was 0.835(95% CI: 0.770-0.901), which was significantly higher than that of TSG and the other prognostic markers, such as C-reactive protein-to-albumin ratio, and procalcitonin-to-albumin ratio. Lastly, RAR was not inferior to TSG in predicting ICU admission, bacteremia, and the length of hospitalization. Conclusions: RAR successfully predicted the in-hospital mortality, ICU admission, bacteremia, and the length of hospitalization of patients with AC, especially in-hospital mortality. RAR is a promising marker that is more convenient than TSG and o

关键词： Acute cholangitis Albumin Biliary drainage Mortality Red blood cell distribution width-to-albumin ratio

Risk Factors in Surgical Site Infections

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Surgical Science 2024年第2期15卷 64-80页

作者： Atilla Duran hüseyin Gülay Mustafa Cem Terzi Department of General Surgery Mersin City Training and Research Hospital Mersin Türkiye Department of General Surgery Baskent University Ankara Türkiye Department of General Surgery Acibadem Kent Hastanesi Izmir Türkiye

Purpose of the Research: Our study aimed to determine and understand the risk factors of surgical site infections in patients operated on in general surgery wards. Method of Research: Between May 2008 and November 2008, 422 consecutive patients who underwent emergency and elective surgeries, excluding breast, goitre and laparoscopic surgeries, were included in the study to determine surgical site infections and risk factors. The patients’ risk factors were selected in the preoperative period, and postoperative 3rd, 7th, and 30th days were checked by the physician responsible for conducting the study regarding surgical site infection. Results and Conclusion: Surgical site infections were defined as incisional and organ/space based on NNIS data. Gender, diabetes mellitus, malignancy, degree of contamination, ASA score ≥ 3, preoperative skin cleansing, duration of intensive care unit stay, duration of hospital stay, growth in wound culture, duration of surgery and incision length were determined as risk factors increasing CAI rates. Especially the degree of contamination, duration of intensive care unit stay, hospitalisation, duration of operation, and growth in wound culture were decisive factors in the development of CAI. As a result of our study, in the light of these data, we concluded that to prevent the development of CAI can be modified, interventions to foreseeable factors can be assessed.

关键词： Infection CAI Risk Patient

Mast cell activation syndrome:An up-to-date review of literature

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World Journal of Clinical Pediatrics 2024年第2期13卷 104-113页

作者： ÖnerÖzdemir Gökçe Kasımoğlu Ayşegül Bak hüseyin Sütlüoğlu Süreyya Savaşan Department of Pediatric Allergy and Immunology Sakarya UniversitySakaryaAdapazarı54100Türkiye Department of Pediatrics Sakarya UniversitySakaryaAdapazarı54100Türkiye Department of Pediatrics Kocaeli City HospitalKocaeli 50123Türkiye Department of Pediatrics Children’s Hospital of MichiganHematology/OncologyCentral Michigan University College of MedicineMount PleasantMI 48859United States Barbara Ann Karmanos Cancer Institute Wayne State UniversityDetroitMI 12345United States

Mast cells are a subtype of white blood cells and are involved in the immune *** cells contain many chemical substances called mediators,which are involved in the allergic *** fact that mast cells play a role in many events that require urgent intervention,especially anaphylaxis,has led to a more detailed study of these *** diseases also caused by dysfunctions of mast cells have been examined in many *** instance,mast cell activation syndrome is known as an augmented number of cells due to decreased cell death,resulting in clinical symptoms affecting many *** main common symptoms include flushing,hypotension,urticaria,angioedema,headache,vomiting and *** the underlying mechanism is not yet clearly known,we aim to review the literature in a broad perspective and bring together the existing knowledge in the light of the literature due to the diversity of its involvement in the body and the fact that it is a little known syndrome.

关键词： Mast cell Mast cell activation syndrome Tryptase histamine

伊尔加兹山脉冰缘地貌发育和土壤形成及其气候的影响(土耳其黑海西岸)

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Journal of Geographical Sciences 2024年第3期34卷 543-570页

作者： DEDE Volkan DENGIZ Orhan DEMIRAG TURAN inci TüRKES Murat SENOL hüseyin SERIN Soner Department of Geography Ardahan UniversityArdahan75002Türkiye Department of Soil Science and Plant Nutrition Faculty of AgricultureOndokuz Mayıs UniversitySamsun55139Türkiye Department of Geography Faculty of Human and Social SciencesSamsun UniversitySamsun55080Türkiye Center for Climate Change and Policy Studies Boğaziçi Universityİstanbul34342Türkiye Faculty of Agriculture Department of Soil Science and Plant NutritionIsparta University of Applied SciencesIsparta32200Türkiye Institute of Social Sciences İstanbul Universityİstanbul34119Türkiye

The main aims of the current study are to determine the morphological features of the periglacial landforms(non-sorted step,mud circle,stony earth circle,thufur,and congeliturbation)located on the Ilgaz Mountains,examine the physicochemical and mineralogical properties with pedological processes of the soils,and assess of the effects of climatic conditions controlling the development of *** Ilgaz Mountains(2587 m a.s.l.),located in the Western Black Sea Region,within the Anatolian Mountains,are important in terms of periglacial landforms(mud circles,stony earth circles,thufurs,non-sorted steps,non-sorted stripes,congeliturbation deposits,and block currents).The descriptive statistics of 123 periglacial landforms measured by fieldworks were *** distribution of freezing and thawing in the Ilgaz Mountains throughout the year was evaluated,and it was found that freezing takes place between December and March,freezing-thawing takes place in April,May,October and November,and thawing takes place between June and *** to soil properties,organic matter content changes from 1.88%to 12.72%in non-sorted step soils,while it is between 2.03%and 12.24%in stony earth circle *** organic matter is observed to be close to congeliturbation deposits at lower ratios compared to non-sorted steps,stony earth circles and mud *** soil reactions on stony earth circles and non-sorted steps vary between slightly acidic and slightly *** the other hand,soil samples taken from the mud circles are different from those taken from the non-sorted steps and stony earth *** soil reaction is acidic,and ph changes between 4.86 and *** lime content also varies between 2.81%and 32.08%,with an average of 12.02%.The texture properties of soils are dominantly loam and clay loam,as in the non-sorted steps,stony earth circles,and mud *** their mineralogical properties,the XRD study was carried out to determine the primer mineral

关键词： periglacial landforms soil formation climate effect Ilgaz Mountains Türkiye

Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 543-562页

作者： h.M.FEIZABAD M.h.YAS Department of Mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQM)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQM)

A VhDL application for kinematic equation solutions of multi-degree-of-freedom systems

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第12期15卷 1164-1173页

作者： hüseyin Oktay ERKOL hüseyin DEMíREL Department of Mechatronics Engineering Faculty of Technology Karabük University Department of Electrical and Electronics Engineering Faculty of Engineering Karabük University

As kinematic calculations are complicated, it takes a long time and is difficult to get the desired accurate result with a single processor in real-time motion control of multi-degree-of-freedom(MDOF) systems. Another calculation unit is needed, especially with the increase in the degree of freedom. The main central processing unit(CPU) has additional loads because of numerous motion elements which move independently from each other and their closed-loop controls. The system designed is also complicated because there are many parts and cabling. This paper presents the design and implementation of a hardware that will provide solutions to these problems. It is realized using the Very high Speed Integrated Circuit hardware Description Language(VhDL) and field-programmable gate array(FPGA). This hardware is designed for a six-legged robot and has been working with servo motors controlled via the serial port. The hardware on FPGA calculates the required joint angles for the feet positions received from the serial port and sends the calculated angels to the servo motors via the serial port. This hardware has a co-processor for the calculation of kinematic equations and can be used together with the equipment that would reduce the electromechanical mess. It is intended to be used as a tool which will accelerate the transition from design to application for robots.

关键词： Multi-degree-of-freedom systems Kinematics Co-processor Serial communication Six-legged robot

holographic dark energy in non-conserved gravity theory

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Communications in Theoretical Physics 2024年第4期76卷 126-133页

作者： h R Fazlollahi Institute of Gravitation and Cosmology Peoples Friendship University of Russia(RUDN University)6 Miklukho-Maklaya StMoscow117198Russia

Recently, reconsidering the Rastall idea T_(μ;νν)^(v)=α_(,μ) through relativistic thermodynamics gives a new form for the scalar field α which led us to construct modern modified theory of gravity debugged ‘non-conserved gravity theory’ Fazlollahi 2023 Euro. Phys. J. C 83 923. This theory unlike other modified theories of gravity cannot directly explain the current acceleration expansion in the absence of the cosmological constant and or existence of other forms of dark energy. hence, in this study we have reinvestigated holographic dark energy Ρ_(X)~h^(2) in the non-conserved theory of gravity. In this context, the density and pressure of dark energy depend on the non-conserved term and density of the dust matter field. As shown, due to non-conservation effects on large-scale structures, unlike the original holographic model, our model onsets an acceleration epoch for the current Universe satisfies observations. Moreover, the interaction and viscous scenarios are studied for this model.

关键词： non-conserved gravity covariant form of thermodynamics holographic dark energy