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Drag pick cutting tests: A comparison between experimental and theoretical results

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第5期10卷 893-906页

作者： serdar Yasar Ali Osman yilmaz Department of Mining Engineering Karadeniz Technical University

This paper aims at reporting the results of a number of drag pick cutting tests on selected igneous rock samples to compare the experimentally determined maximum cutting force （FC） values with theoreti- cally estimated ones. First, a review on theoretical rock cutting models proposed for both chisel and conical picks was presented in detail. Experimental study consists of both chisel and conical pick cutting tests in unrelieved （single-pick） cutting mode with varying cutting depths. FC＇ values were determined from experimental results, and theoretical models were utilized to compute FC for all cutting conditions. Computed and experimentally determined F（ data were then compared for a referenced cutting depth. It is shown that the theoretical models might overestimate or underestimate FC＇ and cannot give reliable results. Finally, explanations for these mismatches were presented.

关键词： Rock cutting mechanics Rock cutting tests Vertical rock cutting rig (VRCR) Cutting force Rock cutting theories

Advances in the treatment of autism spectrum disorder:Wharton jelly mesenchymal stem cell transplantation

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World Journal of Methodology 2025年第1期15卷 72-79页

作者： serdar Kabatas ErdinçCivelek Eyüp Can Savrunlu Umut Karaaslan Özlem Yıldız Erdal Karaöz Department of Neurosurgery University of Health Sciences TurkeyGaziosmanpaşa Training and Research HospitalIstanbul 34255Türkiye Department of Pediatric Allergy-Immunology Institute of Health Sciences Marmara UniversityIstanbul 34865Türkiye Center for Stem Cell&Gene Therapy Research and Practice University of Health Sciences TurkeyIstanbul 34255Türkiye Department of Child and Adolescent Psychiatry University of Health SciencesGaziosmanpaşa Training and Research HospitalIstanbul 34255Türkiye Department of Child and Adolescent Psychiatry Kocaeli University Faculty of MedicineKocaeli 41001Türkiye Center for Regenerative Medicine and Stem Cell Research&Manufacturing Liv HospitalIstanbul 34340Türkiye Department of Histology and Embryology Istinye UniversityFaculty of MedicineIstanbul 34010Türkiye Center for Stem Cell and Tissue Engineering Research and Practice Istinye UniversityIstanbul 34340Türkiye

BACKGROUND Autism spectrum disorder(ASD)is a complex neurodevelopmental disorder with multifaceted *** recent studies,neuroinflammation and immune dysregulation have come to the forefront in its *** are studies suggesting that stem cell therapy may be effective in the treatment of *** To evolve the landscape of ASD treatment,focusing on the potential benefits and safety of stem cell *** A detailed case report is presented,displaying the positive outcomes observed in a child who underwent intrathecal and intravenous Wharton’s jelly-derived mesenchymal stem cells(WJ-MSCs)transplantation combined with *** The study demonstrates a significant improvement in the child’s functional outcomes(Childhood Autism Rating Scale,Denver 2 Developmental Screening Test),especially in language and gross motor *** serious side effects were encountered during the 2-year *** The findings support the safety and effectiveness of WJ-MSC transplantation in managing ASD.

关键词： Autism spectrum disorder Neurorehabilitation Stem cell transplantation Wharton jelly mesenchymal stem cells Inflammation

Predictive plots for conical pick performance using mechanical and elastoplastic properties of rocks

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第5期12卷 1027-1035页

作者： serdar Yasar Department of Mining Engineering Karadeniz Technical UniversityTrabzon61080Turkey

Conical picks are by far the most widely used drag type cutting tools employed on partial face rock excavation *** cutting force and specific energy are two important design parameters for the conical pick performance,and the rock cutting testing is considered as the promising tool for determining these *** the absence of an instrumented cutting rig,researchers generally rely on empirical predictive *** this,this paper suggests predictive plots for estimating the cutting force and specific energy,in consideration of the cutting depth to define the cuttability with conical *** this context,rock cutting tests were carried out on six volcanic rock samples with varying cutting depths using the unrelieved and relieved cutting *** cutting force and specific energy were correlated with the uniaxial compressive strength,Brazilian tensile strength,elasticity modulus,and plasticity *** plots were proposed for different cutting depths in the unrelieved and relieved cutting modes and exponential relationships were obtained among the cuttability parameters,and mechanical and elastoplastic properties of rocks.

关键词： Performance prediction Rock cutting tests Specific energy Cutting force Plasticity index

Comparative seismic design optimization of spatial steel dome structures through three recent metaheuristic algorithms

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Frontiers of Structural and Civil Engineering 2022年第1期16卷 57-74页

作者： serdar CARBAS Musa ARTAR Department of Civil Engineering Karamanoglu Mehmetbey UniversityKaraman 70200Turkey Department of Civil Engineering Bayburt UniversityBayburt 69000Turkey

Steel dome structures,with their striking structural forms,take a place among the impressive and aesthetic load bearing systems featuring large internal spaces without internal *** this paper,the seismic design optimization of spatial steel dome structures is achieved through three recent metaheuristic algorithms that are water strider(WS),grey wolf(GW),and brain storm optimization(BSO).The structural elements of the domes are treated as design variables collected in member *** structural stress and stability limitations are enforced by ASD-AISC ***,the displacement restrictions are considered in design *** metaheuristic algorithms are encoded in MATLAB interacting with SAP2000 for gathering structural reactions through open application programming interface(OAPI).The optimum spatial steel dome designs achieved by proposed WS,GW,and BSO algorithms are compared with respect to solution accuracy,convergence rates,and reliability,utilizing three real-size design examples for considering both the previously reported optimum design results obtained by classical metaheuristic algorithms and a gradient descent-based hyperband optimization(HBO)algorithm.

关键词： steel dome optimization water strider algorithm grey wolf algorithm brain storm optimization algorithm hyperband optimization algorithm

Seismic loss assessment of RC high-rise buildings designed according to Eurocode 8

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Earthquake Engineering and Engineering Vibration 2023年第3期22卷 807-824页

作者： Jelena Pejovic Nina serdar Faculty of Civil Engineering University of MontenegroBulevar Dzordza Vasingtona bbPodgorica 81000Montenegro

A probabilistic seismic loss assessment of RC high-rise(RCHR)buildings designed according to Eurocode 8 and located in the Southern Euro-Mediterranean zone is presented *** loss assessment methodology is based on a comprehensive simulation approach which takes into account ground motion(GM)uncertainty,and the random effects in seismic demand,as well as in predicting the damage states(DSs).The methodology is implemented on three RCHR buildings of 20-story,30-story and 40-story with a core wall structural *** loss functions described by a cumulative lognormal probability distribution are obtained for two intensity levels for a large set of simulations(NLTHAs)based on 60 GM records with a wide range of magnitude(M),distance to source(R)and different site soil conditions(SS).The losses expressed in percent of building replacement cost for RCHR buildings are *** the estimation of losses,both structural(S)and nonstructural(NS)damage for four DSs are *** effect of different GM characteristics(M,R and SS)on the obtained losses are ***,the estimated performance of the RCHR buildings are checked to ensure that they fulfill limit state requirements according to Eurocode 8.

关键词： RC high-rise buildings seismic loss assessment loss functions nonlinear time-history analysis(NLTHA) cumulative lognormal probability distribution random effects Eurocode 8

Thinning effects on biomass and element concentrations of roots in adjacent hornbeam and oak stands in Istanbul,Turkey

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Forest Ecosystems 2021年第1期8卷 1-10页

作者： serdar Akburak Ender Makineci Faculty of Forestry Soil Science and Ecology DepartmentIstanbul University-Cerrahpasa34473 BahcekoySariyerIstanbulTurkey

Background:Thinning is a commonly used treatment in forest management which affects the tree root *** effects of thinning on element concentrations and seasonal change of roots were evaluated in adjacent oak(Quercus frainetto Ten.)and hornbeam(Carpinus betulus L.)stands according to the different root diameter ***:Two replicated control and thinning plots(50m×50 m)were set for each species(hornbeam and oak).Thinning treatments(November 2010)reduced 50%of the basal area in both oak and hornbeam *** were assessed by seasonal collection over 2 years(from October 2010 to October 2012).The roots were then sorted into diameter classes of 0–2mm(fine roots),2–5mm(small roots)and>5mm(coarse roots).C,N,P,K,Ca,Na,Mg,S,Mn,Fe,Al,Zn,Pb,Ni,Cu and Cd were ***:Except coarse roots,the highest root biomasses were determined in April-2011 in all ***-root biomass in oak was found significantly higher in control *** contrast to the oak,the fine-root biomass in the thinned hornbeam plots was higher than in the *** small-root biomass did not significantly differ between the thinned and the control plots in both oak and hornbeam ***,the coarse-root biomass showed significant differences between the control(1989 g∙m^(−2))and thinned plots(1060 g∙m^(−2))in oak,while no difference was detected in *** concentrations of C,Al,Pb,Cd,Ni,Zn,Mn,Na,K,Mg and P in the fine roots of oak were significantly higher in the thinned ***,the concentration of Pb,Cd and Fe in the fine roots was significantly higher in the thinned plots of *** differences were observed between the species for all elements in the fine roots except for C,N and *** particular,elements in the fine roots tended to increase in July in the *** the hornbeam,all element concentrations in the fine roots(except C,N,and S)in the thinned plots showed a tendency to increase in *** concentrations of Pb,Ni,Al,Fe,Cu,Ca,Na,K,Mg and

关键词： Carpinus Coarse root Fine root Quercus Small root

An integrated approach to assess the ecological and chemical status of lakes with HOD/AHOD: a case study of two lakes

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Journal of Oceanology and Limnology 2019年第1期37卷 146-159页

作者： serdar GONCü Erdem ALBEK Anadolu University Ikieylul Campus Environmental Eng.Dept.

The thermal strati?cation of the lakes impedes the transfer of atmospheric oxygen into the lower layers of the lake. In lakes which are af fected by diverse anthropogenic in?uences, the increasing organic matter amounts lead to a sharp decrease in hypolimnetic oxygen amounts, aided by thermal strati?cation,and anaerobic conditions arise. The determination of hypolimnetic oxygen demand(HOD) and areal hypolimnetic oxygen demand(AHOD) and their monitoring represent an integrated approach to investigate the oxygenation of lakes, the nutrient conditions, and the physicochemical dynamics. In this study, two lakes dif fering by size and af fected by dif ferent anthropogenic sources, are investigated in this respect. At?rst, bathymetric studies were conducted to determine the depth, surface area, and volume ***, based on monitoring studies conducted in 2013 and 2014, the thermal strati?cation dynamics and layer properties were established using the relative thermal resistance to mixing(RTRM) index based on temperature and density pro?les. Following this, the oxygen depletion rates were determined by oxygen and temperature pro?ling in the hypolimnion. For the years of 2013 and 2014, the AHOD values for the Borabey Pond which is far from anthropogenic in?uences, were found to be 0.848 and 0.569 g O 2/(m·d), *** AHOD values for the Porsuk Reservoir which was overburdened for years by industrial and domestic pollution were found to be 4.263 and 5.099 g O 2/(m·d), larger than its counterpart by almost sevenfold. The HOD and AHOD monitoring can be considered to a valuable tool for assessing the ecological and chemical status of lakes within Annex 5 of the Water Framework Directive and as an integrated approach to assess and monitor the status of lakes.

关键词： hypolimnetic oxygen demand(HOD) areal hypolimnetic oxygen demand(AHOD) thermal stratifcation relative thermal resistance to mixing(RTRM) Borabey Pond Porsuk Dam

Determination and evaluation of biogas and methane productions of vegetable and fruit wastes with Hohenheim Batch Test method

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International Journal of Agricultural and Biological Engineering 2017年第4期10卷 207-215页

作者： Ali Aybek serdar Üçok Faculty of Agriculture Department of Biosystems EngineeringKahramanmarasSutcu Imam UniversityKahramanmarasTurkey

Nowadays,biogas technology applications are gradually increasing worldwide due to the economic and environmental *** researches and studies related to the determination of the biogas potential of organic waste materials have been carried out in the recent *** to determine the specific methane potential of organic waste materials have a great importance for both design and economical operation of the biogas *** potential that will be recovered from organic wastes is substantial in *** to biogas plants gathering vegetable-fruit wastes and other organic wastes are planned to produce significant amount of renewable energy in Turkish *** to the use of organic wastes,the disposal of waste as well as energy production,soil,water and air pollution in terms of environmental protection are also *** the other hand,the organic wastes produced from plants can also be utilized as fertilizer in vegetable *** this study,the cumulative biogas and methane production of vegetable and fruit wastes were experimentally determined with HBT(Hohenheim Batch Test)*** and methane yields of vegetable and fruit wastes were found as 0.54-0.73 Nm^(3)/(kg ODM)and 0.29-0.37 Nm^(3)/(kg ODM),*** highest value of the cumulative specific methane production was tomato wastes(0.37 Nm^(3)/(kg ODM)),and the lowest value was lettuce wastes(0.29 Nm^(3)/(kg ODM)),as *** average cumulative specific methane production values of mixed vegetable and fruit wastes are determined as 0.34 Nm^(3)/(kg ODM).

关键词： biogas methane production Hohenheim Batch Test vegetable and fruit wastes renewable energy Turkey

A Modified Oppositional Chaotic Local Search Strategy Based Aquila Optimizer to Design an Effective Controller for Vehicle Cruise Control System

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Journal of Bionic Engineering 2023年第4期20卷 1828-1851页

作者： serdar Ekinci Davut Izci Laith Abualigah Raed Abu Zitar Department of Computer Engineering Batman University72100BatmanTurkey Center for Engineering Application and Technology Solutions Ho Chi Minh City Open UniversityHo Chi MinhVietnam Hourani Center for Applied Scientific Research Al-Ahliyya Amman UniversityAmman19328Jordan Computer Science Department Prince Hussein Bin Abdullah Faculty for Information TechnologyAl Al-Bayt UniversityMafraq25113Jordan Faculty of Information Technology Middle East UniversityAmman11831Jordan Applied Science Research Center Applied Science Private UniversityAmman11931Jordan School of Computer Sciences Universiti Sains Malaysia11800PenangPulau PinangMalaysia Sorbonne Center of Artificial Intelligence Sorbonne University-Abu DhabiAbu DhabiUnited Arab Emirates

In this work,we propose a real proportional-integral-derivative plus second-order derivative(PIDD2)controller as an efficient controller for vehicle cruise control systems to address the challenging issues related to efficient *** this regard,this paper is the first report in the literature demonstrating the implementation of a real PIDD2 controller for controlling the respective *** construct a novel and efficient metaheuristic algorithm by improving the performance of the Aquila Optimizer via chaotic local search and modified opposition-based learning strategies and use it as an excellently performing tuning *** also propose a simple yet effective objective function to increase the performance of the proposed algorithm(CmOBL-AO)to adjust the real PIDD2 controller's parameters *** show the CmOBL-AO algorithm to perform better than the differential evolution algorithm,gravitational search algorithm,African vultures optimization,and the Aquila Optimizer using well-known unimodal,multimodal benchmark ***2019 test suite is also used to perform ablation experiments to reveal the separate contributions of chaotic local search and modified opposition-based learning strategies to the CmOBL-AO *** the vehicle cruise control system,we confirm the more excellent performance of the proposed method against particle swarm,gray wolf,salp swarm,and original Aquila optimizers using statistical,Wilcoxon signed-rank,time response,robustness,and disturbance rejection *** also use fourteen reported methods in the literature for the vehicle cruise control system to further verify the more promising performance of the CmOBL-AO-based real PIDD2 controller from a wider *** excellent performance of the proposed method is also illustrated through different quality indicators and different operating ***,we also demonstrate the good performing capability of the CmOBL-AO algorithm for real traffic *** show

关键词： Aquila optimizer Chaotic local search Modified opposition-based learning Real PIDD^(2)controller Vehicle cruise control system Bionic engineering