检索结果-南通市图书馆

Numerical investigation of seismic performance of high modulus columns under earthquake loading

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2019年第4期18卷 811-822页

作者： selcuk Demir Pelin Ozener Abant Izzet Baysal University Bolu 14030 Turkey Yildiz Technical University Istanbul 34210 Turkey

This paper presents the result of two-dimensional fi nite element modeling studies in order to investigate the seismic behavior of high modulus columns in liquefi able soil. Particular attention was paid to the shear stress reduction mechanism of the high modulus columns and the shear strain distribution between soil and columns during earthquake motion. Numerical analyses were performed using a nonlinear elasto-plastic model in Plaxis 2016. The reliability of the numerical simulations was verifi ed through the results of a centrifuge test model designed to investigate the contribution of high modulus columns in liquefaction mitigation. The capability of numerical simulations was assessed primarily through comparison of predicted acceleration-time histories, pore water pressures, and displacements with the measured counterparts. The results of the numerical analysis showed that the presence of the columns did not reduce seismic shear stresses in the soil when compared to the unimproved soil condition and pure shear behavior between soil and column did not develop as expected in the current design methodology.

关键词： liquefaction high modulus column soil improvement UBC3D-PLM

Optimal Control of Microgrids with Multi-stage Mixed-integer Nonlinear Programming Guided Q-learning Algorithm

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2020年第6期8卷 1151-1159页

作者： Yeliz Yoldas selcuk Goren Ahmet Onen the Department of Electrical and Electronics Engineering Abdullah Gul UniversityKayseri38080Turkey the Department of Industrial Engineering Abdullah Gul UniversityKayseri38080Turkey

This paper proposes an energy management system(EMS)for the real-time operation of a pilot stochastic and dynamic microgrid on a university campus in Malta consisting of a diesel generator,photovoltaic panels,and *** objective is to minimize the total daily operation costs,which include the degradation cost of batteries,the cost of energy bought from the main grid,the fuel cost of the diesel generator,and the emission *** optimization problem is modeled as a finite Markov decision process(MDP)by combining network and technical constraints,and Q-learning algorithm is adopted to solve the sequential decision *** proposed algorithm decomposes a multi-stage mixed-integer nonlinear programming(MINLP)problem into a series of single-stage problems so that each subproblem can be solved by using Bellman’s *** prove the effectiveness of the proposed algorithm,three case studies are taken into consideration:(1)minimizing the daily energy cost;(2)minimizing the emission cost;(3)minimizing the daily energy cost and emission cost ***,each case is operated under different battery operation conditions to investigate the battery ***,performance comparisons are carried out with a conventional Qlearning algorithm.

关键词： Cost minimization energy management system microgrid real-time optimization reinforcement learning

Physical and Mechanical Properties of PP Composites based on Different Types of Lignocellulosic Fillers

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2018年第6期33卷 1298-1307页

作者： selcuk ERDOGAN Umit HUNER Trakya University Faculty of Engineering Department of Mechanical Engineering

The presents preparation and characterization of different types of lignocellulosic fillers(pine wood sawdust/walnut shell flour/black rice husk powder) reinforced polypropylene composites were presented. The effect of MAPP as coupling agent(4 wt%) on the physical and mechanical properties was also investigated. Polypropylene composites were prepared at different rates of filler/matrix(wt%) by using extrusion(for melt blending) and hot compression molding process. Maximum values of tensile and flexural strength were obtained as 26.1 and 43.4 MPa, respectively, whereas the elongation at break value was 4.11% at 10% pine wood sawdust reinforced PP. Tensile and flexural modulus of composites reached the maximum values as 3855 and 3633 MPa with the composite of 30% walnut shell flour reinforced PP. Characterization of composites was carried out by using tensile test, flexural test, FT-IR, and SEM.

关键词： natural filler water absorption FTIR polypropylene MAPP

Recent neuroanatomical studies on the neurovascular bundle of the prostate and cavernosal nerves:clinical reflections on radical prostatectomy

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2005年第4期7卷 339-349,页

作者： selcuk Yucel Tibet Erdogru Mehmet Baykara Department of Urology Akdeniz University School of MedicineKampus 07070AntalyaTurkey

The neurovascular bundle of the prostate and cavernosal nerves have been used to describe the same structure ever since the publication of the first studies on the neuroanatomy of the lower urogenital tract of men, studies that were prompted by postoperative complications arising from radical prostatectomy. In urological surgery every effort is made to preserve or restore the neurovascular bundle of the prostate to avoid erectile dysfunction （ED）. However, the postoperative potency rates are yet to be satisfactory despite all advancements in radical prostatectomy technique. As the technology associated with urological surgery develops and topographical studies on neuroanatomy are cultivated, new observations seriously challenge the classical teachings on the topography of the neurovascular bundle of the prostate and the cavernosal nerves. The present review revisits the classical and most recent data on the topographical anatomy of the neurovascular bundle of the prostate prostatectomy techniques.

关键词： prostate cancer cavernosal nerves neurovascular bundle neuroanatomy prostatectomy laparoscopy robotics nerve graft penile erection

在线全文

学校读者我要写书评

暂无评论

预测翻车华尔街错在哪儿了?

商业周刊（中文版） 2024年第1期 20-21页

作者： Alexandra Semenova Sagarika Jaisinghani Liz Capo McCormick selcuk Gokoluk Ye Xie Sujata Rao-Coverley Matt Turner 孟洁冰(译) 不详

回顾2022年底,不管是股票部门还是债券部门,无论是大公司还是小机构,整个华尔街的气氛都很低落。当时似乎大家都在未雨绸缪,认为经济衰退即将到来。在摩根士丹利(Morgan Stanley),看跌美股的策略师迈克·威尔逊(Mike Wilson)迅速成为市... 详细信息

回顾2022年底,不管是股票部门还是债券部门,无论是大公司还是小机构,整个华尔街的气氛都很低落。当时似乎大家都在未雨绸缪,认为经济衰退即将到来。在摩根士丹利(Morgan Stanley),看跌美股的策略师迈克·威尔逊(Mike Wilson)迅速成为市场宠儿,他预测标准普尔500指数即将大跌。

关键词：摩根士丹利经济衰退标准普尔500指数美股华尔街债券股票未雨绸缪

Prediction of mine drainage generation potential and the prevention method of the groundwater pollution in the Gümüskoy(Kütahya)mineralization area,NW Turkey

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Mountain Science 2020年第10期17卷 2387-2404页

作者： selcuk ALEMDAG Enver AKARYALI Mehmet Ali GuCER Department of Geological Engineering Faculty of Engineering and Natural SciencesGumusşhane UniversityGumushane29100Turkey

One of the leading factors of seepage contamination is mine drainage,which creates serious ecological risks on the environment both during operation and post-mining *** this study,experimental processes have been carried out to determine the occurrence of mine drainage in the Gümüskoy(Kütahya)mineralization area(Northwest Turkey).The prevention method for potential mine drainage occurrence has been also *** enrichment was observed which are directly related to mineralization in trace element concentrations,especially in potentially toxic metals such as Ag,Cd,Mo,Ba,Bi,and *** on short-term tests,mine drainage formation has not been expected according to the p H(7.36-9.38),contact leaching,and acid-base accounting ***,in the long-term,acid generation potential has been expected because of weathering and oxidation in terms of rock type and mineralization in the ***,in order to prevent groundwater contamination in the event of a possible formation of mine drainage,the hydraulic conductivity of the stock area bedrock was evaluated by the in situ tests performed in the field and it was found to be moderately permeable(K=1.9×10^-6 m/s).In order to make the stock area bedrock impermeable,natural clay will be laid and compressed at the base of the stock *** the finite elements were modeled by seepage analysis,the seepage discharge to be formed on the base rock at a depth of 5 m was determined as 3.17×10^-19 m^3/*** the discharge value determined in the seepage analysis after modeling is very close to zero,contamination of possible ground and surface water will be prevented.

关键词： Ecological risks Environmental assessment Mine drainage Seepage analysis

Stability evaluation of the Gümüshane-Akcakale cave by numerical analysis method

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2019年第9期16卷 2150-2158页

作者： ALEMDAG selcuk ZEYBEK Halil Ibrahim KULEKCI Gokhan Department of Geological Engineering Gumushane UniversityGumushane 29100Turkey Department of Geography Ondokuz Mayis UniversitySamsun 55105Turkey Department of Mining Engineering Gumushane UniversityGumushane 29100Turkey

The Ak?akale Cave is located in the vicinity of the Arsa neighborhood within the boundaries of the Ak?akale village, Gümü?hane, Turkey. The cave is rich in cave formations(stalactite, stalagmite, cave pearl, cave flower, wall travertines). Thus, the appropriateness of opening the cave to visitors to boost tourism is of importance for the local and national economy. This study analyzes the stability of the Ak?akale Cave using a numerical analysis method. According to the results of the total displacement analysis, there are displacements in the entrance, ceiling, and sidewalls of the cave ranging from 1 mm to 48 mm. It seems that the entrance, ceiling, and sidewalls of the cave face a high risk of local or sudden collapse. According to the deformation analysis of the length section of the cave examined, local collapses may occur especially in the first 75 m from the entrance of the cave. We believe that this situation would not carry a risk for the Arsa neighborhood for now. In conclusion, the results of the stability analysis and in-situ observations showed clear evidence of former and ongoing cave-ins(collapses) and the Ak?akale Cave faces a high risk of local or sudden collapse. Thus, although the Ak?akale Cave is one of the most prominent karst caves in Turkey, it seems to be not appropriate to open the cave to tourist visits.

关键词： Akcakale Cave Dripstone Finite element method Karst caves Numerical analysis

Stereotactic radiosurgery for haemorrhagic cerebral cavernous malformation:a multi-institutional,retrospective study

在线全文

学校读者我要写书评

暂无评论

Stroke & Vascular Neurology 2024年第3期9卷 221-229,I0130,I0131页

作者： Chloe Dumot Georgios Mantziaris Sam Dayawansa Zhiyuan Xu Stylianos Pikis selcuk Peker Yavuz Samanci Gokce D Ardor Ahmed M Nabeel Wael A Reda Sameh R Tawadros Khaled Abdelkarim Amr M N El-Shehaby Reem M Emad Eldin Ahmed H Elazzazi Nuria Martínez Moreno Roberto MartínezÁlvarez Roman Liscak Jaromir May David Mathieu Jean-Nicolas Tourigny Manjul Tripathi Akshay Rajput Narendra Kumar Rupinder Kaur Piero Picozzi Andrea Franzini Herwin Speckter Wenceslao Hernandez Anderson Brito Ronald E Warnick Juan Alzate Douglas Kondziolka Greg N Bowden Samir Patel Jason Sheehan Department of Neurological Surgery Hospices Civils de LyonLyonFrance Department of Neurological Surgery University of VirginiaCharlottesvilleVirginiaUSA Department of Neurosurgery Koc University School of MedicineIstanbulTurkey Gamma-knife Center Nasser institute HospitalCairoEgypt Neurosurgery Department Benha UniversityBenhaEgypt Departments of Neurosurgery Ain Shams UniversityCairoEgypt Department of Clinical Oncology Ain Shams UniversityCairoEgypt Department of Radiation Oncology National Cancer InstituteCairo UniversityGizaEgypt Faculty of Medicine Extended Modular ProgramAin Shams UniversityCairoEgypt Department of Radiosurgery Rúber Internacional HospitalMadridSpain Department of Stereotactic and Radiation Neurosurgery Na Homolce HospitalPragueCzech Republic Neurosurgery Centre de recherche du CHUSUniversitéde SherbrookeSherbrookeQuebecCanada Neurosurgery PGIMERChandigarhChandigarhIndia Radiation Therapy PGIMERChandigarhChandigarhIndia Neurosurgery IRCCS Istituto Clinico HumanitasRozzanoMilanItaly Dominican Gamma Knife Center and Radiology Department CEDIMATSanto DomingoDominican Republic Gamma Knife Center Mayfield ClinicThe Jewish Hospital-Mercy HealthCincinnatiOhioUSA Neurosurgery NYU Langone HealthNew YorkNew YorkUSA Neurosurgery University of AlbertaEdmontonAlbertaCanada Division of Radiation Oncology Department of OncologyUniversity of AlbertaEdmontonAlbertaCanada

Background Cerebral cavernous malformations(CCMs)frequently manifest with *** radiosurgery(SRS)has been employed for CCM not suitable for *** effect on reducing haemorrhage risk is still *** aim of this study was to expand on the safety and efficacy of SRS for haemorrhagic *** This retrospective multicentric study included CCM with at least one haemorrhage treated with single-session *** annual haemorrhagic rate(AHR)was calculated before and after *** event analysis and Cox regression were used to evaluate factors associated with *** radiation effects(AREs)and occurrence of new neurological deficits were *** The study included 381 patients (median age:37.5 years(Q1–Q3:25.8–51.9))with 414 *** AHR from diagnosis to SRS excluding the first haemorrhage was 11.08 per 100 CCM-years and was reduced to 2.7 per 100 CCM-years after *** recurrent event analysis,SRS,HR 0.27(95%CI 0.17 to 0.44),p13 Gy,HR 2.27(95%CI 1.20 to 4.32),p=0.012 and the presence of DVA,HR 2.08(95%CI 1.00 to 4.31),p=0.049 were factors associated with higher probability of post-SRS ***-SRS haemorrhage was symptomatic in 22 out of 381(5.8%)patients,presenting with transient(15/381)or permanent(7/381)neurological *** occurred in 11.1%(46/414)CCM and was responsible for transient neurological deficit in 3.9%(15/381)of the patients and permanent deficit in 1.1%(4/381)of the *** doses>13 Gy and CCM volume>0.7 cc were associated with increased risk of ARE.

关键词： doses haemorrhagic diagnosis

Advanced exergy analysis of the turbojet engine main components considering mexogenous, endogenous, exegenous, avoidable and unavoidable exergy destructions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Propulsion and Power Research 2022年第3期11卷 391-400页

作者： Hakan Caliskan selcuk Ekici Yasin Sohret Department of Mechanical Engineering Faculty of EngineeringUsak UniversityUsak64200Turkey Department of Aviation Igdir UniversityIgdir76000Turkey Department of Airframe and Powerplant Maintenance School of Civil AviationSuleyman Demirel UniversityIsparta32700Turkey

In this study, exergy dynamic and advanced exergy analyses are applied to theturbojet engine to assess its mexogenous, endogenous, exogenous, avoidable and unavoidableexergies under the environment conditions of 15 C temperature and 1 bar pressure. Themaximum exergy point in the turbojet engine is found for the combustor in which C11H23(Jet-A1) fuel is combusted with air, while the minimum one is determined for the aircompressor head where the free air enters. The combustion chamber has the maximum fuel,product and irreversibility rates and the air compressor has the minimum fuel and product ex-ergy values, while the minimum irreversibility is found for the turbine. Maximum improvementpotential rate is found for the combustion chamber (5141.27 kW), while minimum rate is deter-mined for the turbine of system (6.95 kW). Also, the turbine component has the highest exergyefficiency (97.20%) due to its expansion process, while combustion chamber component hasthe lowest exergy efficiency (55.39%) due to low efficient combustion process of the ***, the mexogenous exergy destructions from maximum to minimum are found for the combustion chamber, air compressor and gas turbine units, respectively. Considering exergydynamic analysis, the mexogenous exergy destruction rates of the combustion chamber, aircompressor and gas turbine are found as 184.4 kW, 103.97 kW and 9.99 kW, *** all results, the combustion chamber is the primer component to be handled for bet-ter efficiency and improvement.

关键词： Advanced exergy Efficiency Gas turbine Jet fuel Mexogenous Turbojet Thermodynamic analysis Aircraft