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Journal of Mountain Science 2017年第3期14卷 432-441页

作者： nima babanouri Hesam DEHGHANI Department of Mining Engineering Hamedan University of Technology***HamedanIran

A reservoir landslide not only reduces the water storage capacity, but also causes extensive damages to the dam body, power/water transmission lines, roads, and other infrastructures. The Latian Dam, located 35 km north east of Tehran （Iran）, is one of the cases which has encountered serious problems with instability of its rock abutments. This paper addresses the stability analysis of the right abutment of the Latian Dam using limit equilibrium and numerical methods. Geomechanical characteristics of the rock abutment were first estimated based on engineering classification of the rock mass. Different search methods were examined for locating the critical circular/non-circular slip surface in conjunction with the general limit equilibrium method. The effect of variabi]ity of rock mass properties, water table, and earthquake load on the factor of safety （FS） and probability of failure （PF） was studied. In the event of rapid drawdown in the reservoir, the limit equilibrium analysis calculated FS=1.067 and PF=21.1%, and the numerical analysis returned FS=1.01. The results of the analyses suggest that the right abutment of the Latian Dam is prone to slide and needs treatment. Investigations demonstrated that a slope reduction by 15° at the upper part of the abutment would meet stability conditions even in the worst-case scenario （FS=1.297 and PF=2.07%）.

关键词： Reservoir landslide Limit equilibrium Numerical modeling Reliability Slope stabilization

Study on failure mechanism of room and pillar with different shapes and configurations under uniaxial test and numerical simulation compression using experimental test and numerical simulation

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Underground Space 2023年第2期9卷 105-121页

作者： Vahab Sarfarazi nima babanouri Shahin Fattahi Kaveh Asgari Department of Mining Engineering Hamedan University of TechnologyHamedanIran Department of Mining Engineering Shahid Bahonar University of KermanKermanIran

Experimental and discrete element methods were used to investigate the failure behavior of room and pillar with different configura-tions under uniaxial *** samples with dimension of 15 cm×15 cm×5 cm were *** the specimens,rooms and pillars with different configurations were *** room dimension was 1 cm×1 cm,and the pillar dimension was according to the room *** different configurations were chosen for rooms and *** axial load was applied to the model by rate of 0.05 mm/*** results show that the failure process was mostly governed by both the non-persistent joint angle and joint *** compressive strength of the specimens was related to the fracture pattern and failure mechanism of the *** was shown that the shear behaviour of pillars was related to the number of the induced tensile cracks,which increased by increasing the room *** compressive strength of samples increased with the increase of the room *** failure pattern and failure strength are similar in both methods,i.e.,the experimental testing and the numerical simulation.

关键词： PFC2D Physical test Rock pillar

A New Formulation of the Scaled Boundary Finite Element Method for Heterogeneous Media:Application to Heat Transfer Problems

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Acta Mechanica Solida Sinica 2024年第2期37卷 285-296页

作者： nima Noormohammadi Nazanin Pirhaji Khouzani Department of Civil Engineering Isfahan University of TechnologyIsfahan84156-83111Iran

The solution to heat transfer problems in two-dimensional heterogeneous media is attended based on the scaled boundary finite element method(SBFEM)coupled with equilibrated basis functions(EqBFs).The SBFEM reduces the model order by scaling the boundary solution onto the inner *** this end,tri-lateral elements are emanated from a scaling center,followed by the development of a semi-analytical solution along the radial direction and a finite element solution along the circumferential/boundary *** discretization is thus limited to the boundaries of the model,and the semi-analytical radial solution is found through the solution of an eigenvalue problem,which restricts the methods’applicability to heterogeneous *** this research,we first extracted the SBFEM formulation considering the heterogeneity of the ***,we replaced the semi-analytical radial solution with the EqBFs and removed the eigenvalue solution step from the *** varying coefficients of the partial differential equation(PDE)resulting from the heterogeneity of the media are replaced by a finite series in the radial and circumferential directions of the element.A weighted residual approach is applied to the radial *** equilibrated radial solution series is used in the new formulation of the SBFEM.

关键词： Scaled boundary finite element method Equilibrated basis functions Heat transfer

Ensemble Wind Power Prediction Interval with Optimal Reserve Requirement

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 65-76页

作者： Hamid Rezaie Cheuk Hei Chung nima Safari the Saskatchewan Power Corporation(SaskPower) ReginaSaskatchewanCanada the Department of Electrical and Computer Engineering and Department of Human Biology University of TorontoTorontoON M5S 3G4Canada the Alberta Electric System Operator(AESO) CalgaryAlbertaCanada

Wind power prediction interval(WPPI)models in the literature have predominantly been developed for and tested on specific case ***,wind behavior and characteristics can vary significantly across ***,a prediction model that performs well in one case might underperform in *** address this shortcoming,this paper proposes an ensemble WPPI framework that integrates multiple WPPI models with distinct characteristics to improve *** important and often overlooked factor is the role of probabilistic wind power prediction(WPP)in quantifying wind power uncertainty,which should be handled by operating *** reserve in WPPI frameworks enhances the efficacy of *** this regard,the proposed framework employs a novel bi-layer optimization approach that takes both WPPI quality and reserve requirements into *** analysis with different real-world datasets and various benchmark models validates the quality of the obtained WPPIs while resulting in more optimal reserve requirements.

关键词： Ensemble model linear programming operating reserve optimal reserve requirement prediction interval probabilistic prediction renewable integration uncertainty representation wind power prediction(WPP)

Experimental measurement and numerical modeling of deformation behavior of breast cancer cells passing through constricted microfluidic channels

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Microsystems & Nanoengineering 2024年第1期10卷 129-147页

作者： Pouyan Keshavarz Motamed Hesam Abouali Mahla Poudineh nima Maftoon Department of Systems Design Engineering University of WaterlooWaterlooON N2L 3G1Canada Center for Bioengineering and Biotechnology University of WaterlooWaterlooON N2L 3G1Canada Department of Electrical and Computer Engineering University of WaterlooWaterlooON N2L 3G1Canada

During the multistep process of metastasis,cancer cells encounter various mechanical forces which make them deform *** accurate in-silico models,capable of simulating the interactions between the mechanical forces and highly deformable cancer cells,can pave the way for the development of novel diagnostic and predictive methods for metastatic ***-network models of cancer cell,empowered by our recently proposed identification approach,promises a versatile numerical tool for developing experimentally validated models that can simulate complex interactions at cellular *** this numerical tool,we presented spring-network models of breast cancer cells that can accurately replicate the experimental data of deformation behavior of the cells flowing in a fluidic domain and passing narrow constrictions comparable to ***,using high-speed imaging,we experimentally studied the deformability of breast cancer cell lines with varying metastatic potential(MCF-7(less invasive),SKBR-3(medium-high invasive),and MDA-MB-231(highly invasive)in terms of their entry time to a constricted microfluidic *** observed that MDA-MB-231,that has the highest metastatic potential,is the most deformable cell among the ***,by focusing on this cell line,experimental measurements were expanded to two more constricted microchannel *** experimental deformability data in three constricted microchannel sizes for various cell sizes,enabled accurate identification of the unknown parameters of the spring-network model of the breast cancer cell line(MDA-MB-231).Our results show that the identifed parameters depend on the cell size,suggesting the need for a systematic procedure for identifying the size-dependent parameters of spring-network models of *** the numerical results show,the presented cell models can simulate the entry process of the cell into constricted channels with very good agreements with the measured experimen

关键词： strict passing numerical

Microphysical Characteristics of Rainfall Based on Long-Term Observations with a 2DVD in Yangbajain,Tibet

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Advances in Atmospheric Sciences 2024年第9期41卷 1721-1734页

作者： Ming LI Yongheng BI Yonghai SHEN Yinan WANG Ciren nima Tianlu CHEN Daren LYU Key Laboratory for Cosmic Rays of the Ministry of Education Tibet UniversityLhasa 850000China Key Laboratory of Middle Atmosphere and Global Environment Observation(LAGEO) Institute of Atmospheric PhysicsChinese Academy of ScienceBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Raindrop size distribution(DSD)plays a crucial role in enhancing the accuracy of radar quantitative precipitation estimates in the Tibetan Plateau(TP).However,there is a notable scarcity of long-term,high-resolution observations in this *** address this issue,long-term observations from a two-dimensional video disdrometer(2DVD)were leveraged to refine the radar and satellite-based algorithms for quantifying precipitation in the hinterland of the *** was observed that weak precipitation(R<1,mm h-1)accounts for 86%of the total precipitation time,while small raindrops(D<2 mm)comprise 99%of the total raindrop ***,the average spectral width of the DSD increases with increasing rain *** DSD characteristics of convective and stratiform precipitation were discussed across five different rain rates,revealing that convective precipitation in Yangbajain(YBJ)exhibits characteristics similar to maritime-like *** constrained relationships between the slopeΛand shapeμ,D_(m)and N_(w)of gamma DSDs were ***,we established a correlation between the equivalent diameter and drop axis ratio and found that raindrops on the TP attain a nearly spherical ***,the application of the rainfall retrieval algorithms of the dual-frequency precipitation radar in the TP is improved based on the statistical results of the DSD.

关键词： Tibetan Plateau raindrop size distribution 2DVD dual frequency radar microphysical features

Synergistic Swarm Optimization Algorithm

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2557-2604页

作者： Sharaf Alzoubi Laith Abualigah Mohamed Sharaf Mohammad Sh.Daoud nima Khodadadi Heming Jia Faculty of Computer Sciences and Informatics Amman Arab UniversityAmman11953Jordan Computer Science Department Al Al-Bayt UniversityMafraq25113Jordan Department of Electrical and Computer Engineering Lebanese American UniversityByblos13-5053Lebanon Hourani Center for Applied Scientific Research Al-Ahliyya Amman UniversityAmman19328Jordan MEU Research Unit Middle East UniversityAmman11831Jordan Applied Science Research Center Applied Science Private UniversityAmman11931Jordan School of Computer Sciences Universiti Sains MalaysiaPulau Pinang11800Malaysia School of Engineering and Technology Sunway University MalaysiaPetaling Jaya27500Malaysia Department of Industrial Engineering College of EngineeringKing Saud UniversityP.O.Box 800Riyadh11421Saudi Arabia College of Engineering Al Ain UniversityAbu Dhabi112612United Arab Emirates Department of Civil and Architectural Engineering University of MiamiCoral Gables1251USA School of Information Engineering Sanming UniversitySanming365004China

This research paper presents a novel optimization method called the Synergistic Swarm Optimization Algorithm(SSOA).The SSOA combines the principles of swarmintelligence and synergistic cooperation to search for optimal solutions efficiently.A synergistic cooperation mechanism is employed,where particles exchange information and learn from each other to improve their search *** cooperation enhances the exploitation of promising regions in the search space while maintaining exploration ***,adaptive mechanisms,such as dynamic parameter adjustment and diversification strategies,are incorporated to balance exploration and *** leveraging the collaborative nature of swarm intelligence and integrating synergistic cooperation,the SSOAmethod aims to achieve superior convergence speed and solution quality performance compared to other optimization *** effectiveness of the proposed SSOA is investigated in solving the 23 benchmark functions and various engineering design *** experimental results highlight the effectiveness and potential of the SSOA method in addressing challenging optimization problems,making it a promising tool for a wide range of applications in engineering and *** codes of SSOA are available at:https://***/matlabcentral/fileexchange/153466-synergistic-swarm-optimization-algorithm.

关键词： Synergistic swarm optimization algorithm optimization algorithm metaheuristic engineering problems benchmark functions

XIZANG AIMS TO BECOME AN OUTDOOR SPORTS HEAVEN

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China's Tibet 2024年第5期35卷 20-26页

作者： Huadan nima 不详

Enriched with stunning landscape and soaring mountains,the Xizang Autonomous Region has been making big efforts to make the region a destination for climbers and other outdoor sports *** climber and guide Ngakwang Dorje,41,established an outdoor sports company ten years ago,specializing in activities like climbing,trekking,and hiking for domestic outdoor sports enthusiasts.

关键词： landscape mountains outdoor

Propofol sedation in routine endoscopy:A case series comparing target controlled infusion vs manually controlled bolus concept

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World Journal of Gastrointestinal Endoscopy 2024年第1期16卷 11-17页

作者： Riad Sarraj Lorenz Theiler nima Vakilzadeh Niklas Krupka Reiner Wiest Department of Visceral Surgery and Medicine Inselspital University HospitalBern 3010Switzerland Clinic for Anesthesia PerioperativeEmergency&Intensive Care MedicineKantonsspital AarauAarau 5001Switzerland Department of Nephrology and Hypertension University Hospital LausanneLausanne 1011Switzerland

BACKGROUND Many studies have addressed safety and effectiveness of non-anaesthesiologist propofol sedation(NAPS)for gastrointestinal(GI)endoscopy Target controlled infusion(TCI)is claimed to provide an optimal sedation regimen by avoiding under-or *** To assess safety and performance of propofol TCI sedation in comparison with nurse-administered *** Fouty-five patients undergoing endoscopy under TCI propofol sedation were prospectively included from November 2016 to May 2017 and compared to 87 patients retrospectively included that underwent endoscopy with *** were matched for age and endoscopic *** recorded time of sedation and endoscopy,dosage of medication and adverse *** There was a significant reduction in dose per time of propofol administered in the TCI group,compared to the NAPS group(8.2±2.7 mg/min vs 9.3±3.4 mg/min;P=0.046).The time needed to provide adequate sedation levels was slightly but significantly lower in the control group(5.3±2.7 min vs 7.7±3.3 min;P<0.001),nonetheless the total endoscopy time was similar in both *** differences between TCI and bolus-sedation was observed for mean total-dosage of propofol rate as well as adverse *** This study indicates that sedation using TCI for GI endoscopy reduces the dose of propofol necessary per minute of *** may translate into less adverse ***,further and randomized trials need to confirm this trend.

关键词： Sedation Endoscopy Propofol Target controlled infusion Non-anaesthesiologist propofol sedation Adverse event

Analysis of Dry-Wet Climate Change Characteristics and Main Influencing Factors in Main Grain Producing Area of Tibet from 1980 to 2021

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Agricultural Biotechnology 2024年第2期13卷 43-49,63页

作者： Sangbu ZHUJIE Cunjie ZHANG Puchi ZHAXI Deji BAIMA Lamu nima Ciwang PINGCUO Nanmulin Meteorological Bureau of Tibet Autonomous Region Shigatse 857000China National Climate Center Beijing 100089China Shigatse Agricultural Science Research and Promotion Center Shigatse 857000China Dingri County Meteorological Bureau of Tibet Autonomous Region Shigatse 857000China

Based on the daily meteorological observation data of seven meteorological stations in southern Tibet from 1980 to 2021 (April-October), the temporal and spatial variation characteristics and influencing factors of aridity index ( AI ) in the growing season of major grain producing areas in Tibet were studied by using climate tendency rate, Mann-Kendal test, Morlet wavelet analysis, GIS hybrid interpolation method, Pearson correlation coefficient, contribution rate analysis and other methods. The results showed that the average AI in the main grain producing areas of Tibet was 1.7, which belonged to the semi-arid area, and the overall trend was decreasing (humidifying) (-0.036/10 a). The linear decreasing trend was different in different regions, and the area around Lhatse County was the most significant (-0.26/10 a). AI had no obvious abrupt change, and had long- and medium-term fluctuation characteristics of 24 years, 6 years. The spatial distribution was uneven, and had the characteristics of ‘shrinking arid area and expanding humid area . The contribution rates of the main climate influencing factors of AI varied in different regions. In general, the contribution rates after quantification was as follows: precipitation (34.9%)>relative humidity (28.4%)>sunshine (19.9%)>maximum temperature (12.4%).

关键词： Tibet Main production area Climate Aridity Contribution rate