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Journal of Mountain Science 2011年第2期8卷 124-130页

作者： Morteza AHMADI Majid ESLAMI Department of Mining Engineering Tarbiat Modares University Ghaem consulting Engineers

The stability of slopes is always of great concern in the field of rock engineering. The geometry and orientation of pre-existing discontinuities show a larger impact on the behavior of slopes that is often used to describe the measurement of the steepness, incline, gradient, or grade of a straight line. One of the structurally controlled modes of failure in jointed rock slopes is plane failure. There are numerous analytical methods for the rock slope stability including limit equilibrium, stress analysis and stereographic methods. The limiting equilibrium methods for slopes under various conditions against plane failure have been previously proposed by several investigators. However, these methods do not involve water pressure on sliding surfaces assessments due to water velocity and have not yet been validated by case study results. This paper has tried to explore the effects of forces due to water pressure on discontinuity surfaces in plane failure through applying the improved equations. It has studied the effect of water flow velocity on sliding surfaces in safety factor, as well. New equations for considering water velocity (fluid dynamics) are presented. To check the validity of the suggested equations, safety factor for a case study has been determined. Results show that velocity of water flow had significant effect on the amount of safety factor. Also, the suggested equations have higher validity rate compared to the current equations.

关键词：水库滑坡水流速度边坡稳定性飞机故障不连续性法平面极限平衡方法大坝

Scleractinian coral communities of Hormuz Island in the PersianGulf

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Acta Oceanologica Sinica 2022年第12期41卷 48-57页

作者： Yamin Pouryousef Jafar Seyfabadi Hamid Rezai Alireza Mahvari Mohammad Ali Jafari Department of Marine Biology Faculty of Marine SciencesTarbiat Modares UniversityNoor 46417Iran Darya Negar Pars consulting Engineers Tehran 14669Iran Department of Environment Hormozgan Provincial Directorate Bandar Abbas 79168Iran

The abundance and health of scleractinian coral communities of Hormuz Island were *** this purpose,we employed 20 m line intercept transects—12 in the intertidal zone and 15 subtidally to evaluate coral cover and community *** estimated dead coral coverage was 6.21%±0.81%,while live coral coverage was 16.93%±1.81%,considered as very ***,12 genera were recorded,of which Porites with 11.9%±1.4%live cover was the dominant,while Goniopora had the least cover(0.07%±0.08%).Based on Mann-Whitney U-test,live coral coverage,dead coral coverage,algal coverage,cover of other benthic organisms and abiotic components showed significant univariate differences between zones(p<0.05).The Spearman correlation test between the abundance of biotic and abiotic components indicated significant negative correlation of live coral and sand with zoantharian and significant positive correlation of algae and other benthic organisms with *** reef health indices used for the corals indicated that,in general,the environmental conditions were not suitable,which could be attributed to both natural and anthropogenic factors,the most important of which was zoantharian’overgrowth on the scleractinian corals in this region.

关键词： scleractinian corals zoantharian reef health indices Hormuz Island Persian Gulf

Research on power-supply cost of regional power system under carbon-peak target

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Global Energy Interconnection 2022年第1期5卷 31-43页

作者： Jingyi Wang Min Cang Xiaomeng Zhai Shuang Wu Xi Cheng Lei Zhu State Grid Jiangsu Economic Research Institute Nanjing 210008JiangsuP.R.China China Electricity Council Technical and Economic consulting Centre of Electric Power Construction Beijing 100053P.R.China

With the establishment of the carbon-peak target by 2030,the direction of carbon emission reduction in China’s energy system has been further *** the industry with the largest proportion of carbon emissions in China,the lowcarbon transformation of the electric power industry is critical to realize the carbon-peak *** research mostly focuses on technical analysis or system cost accounting of the carbon-peak realization path at the national *** is a lack of targeted research on regional power systems with complex inter-regional power flow exchange and limited energy resource ***,the calculation of the system cost lacks the perspective of the life cycle and ignores the inertia of the stock and change inertia of incremental *** the perspective of the life cycle,this study proposes a calculation model of power supply cost for regional power systems according to the carbon-peak target,analyzes the realization path of the carbon target from an economic perspective,and provides references for the path selection and policy formulation of system transformation.

关键词： Carbon peak Power system Renewable energy sources System cost Life cycle

Extensions in adaptive model tracking with mitigated passivity conditions

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Chinese Journal of Aeronautics 2013年第1期26卷 136-150页

作者： Itzhak BARKANA BARKANA consulting 11/3 Hashomer St. Ramat Hasharon 47209 Israel

Feasibility of nonlinear and adaptive control methodologies in multivariable linear timeinvariant systems with state space realization {A, B, C} has apparently been limited by the standard strict passivity （or positive realness） conditions that imply that the product CB must be positive definite symmetric. More recently the symmetry condition has been mitigated, requiring instead that the not necessarily symmetric matrix CB be diagonalizable and with positive real eigenvalues. However, although the mitigated conditions are useful in proving pure stabilizability with Adaptive Controllers, the Model Tracking question has remained open and counterexamples seem to demonstrate total divergence of standard model reference adaptive controllers when the regular passivity conditions are not fully satisfied. Therefore, this paper further extends the previous results, showing that the new passivity conditions do guarantee stability with adaptive model tracking. Examples show how the new conditions solve the case of flexible structures with unknown parameters when perfect collocation is not possible. Also, the so-called counterexamples become simple, well-behaved, examples.

关键词： Almost strict passivity Control systems Passivity Simple adaptive control Stability

An elastic-plastic analysis of short-leg shear wall structures during earthquakes

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Earthquake Engineering and Engineering Vibration 2012年第4期11卷 525-540页

作者： Ding Jianguo Zhu Ying School of Sciences Nanjing University of Science and Technology Huaxin consulting CO. Ltd

Short-leg shear wall structures are a new form of building structure that combine the merits of both frame and shear wall structures. Its architectural features, structure bearing and engineering cost are reasonable. To analyze the elastic-plastic response of a short-leg shear wall structure during an earthquake, this study modified the multiple-vertical-rod element model of the shear wall, considered the shear lag effect and proposed a multiple-vertical-rod element coupling beam model with a new local stiffness domain. Based on the principle of minimum potential energy and the variational principle, the stiffness matrixes of a short-leg shear wall and a coupling beam are derived in this study. Furthermore, the bending shear correlation for the analysis of different parameters to describe the structure, such as the beam height to span ratio, short-leg shear wall height to thickness ratio, and steel ratio are introduced. The results show that the height to span ratio directly affects the structural integrity; and the short-leg shear wall height to thickness ratio should be limited to a range of approximately 6.0 to 7.0. The design of short-leg shear walls should be in accordance with the ＂strong wall and weak beam＂ principle.

关键词： short-leg shear wall multiple-vertical-rod element model shear lag effect bending shear correlationcoefficient coupling beam stiffness matrix elastic-plastic analysis

Conductor Arrangement and Phase Sequence Optimization Scheme for 500 kV Four-Circuit Transmission Lines on Same Tower

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Energy Engineering 2023年第10期120卷 2287-2306页

作者： Deng Lu Xujun Lang Bo Yang Ziyang Li Hang Geng Power Grid Design and Research Institute Shandong Electric Power Engineering Consulting Institute Co.Ltd.Jinan250012China School of Electrical Engineering Shandong UniversityJinan250061China

The four-circuit parallel line on the same tower effectively solves the problems faced by the line reconstruction and construction under the condition of the increasing shortage of transmission *** the conductor and phase sequence arrangement of multiple transmission lines is conducive to improving electromagnetic and electrostatic coupling caused by electromagnetic *** paper uses the ATP-EMTP simulation software to build a 500 kV multi-circuit transmission line on the same *** stimulates the induced voltage and current values of different line lengths,tower spacing,vertical and horizontal spacing between different circuits,phase sequence arrangement,and nominal tower ***,use the BP neural network optimized by a genetic algorithm to predict the induced voltage and current under the unknown conductor and phase sequence ***,based on multi-objective particle swarm algorithm to construct the optimization model of conductor arrangement scheme of overhead transmission line,combined with electromagnetic environment control index,determine the optimal conductor arrangement scheme by the size of particle fitness function,a significant reduction in induced voltages and currents between transmission lines and the four-circuit conductor layout scheme meeting the requirements of the electromagnetic environment is obtained,which provides a reference for the tower design of the transmission station project.

关键词： Spatial arrangement phase sequence arrangement genetic algorithm BP neural network multi-objective particle swarm algorithm

From Lab to Market:The Rising Recombinant Collagen in the Cosmetic Industry

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China Detergent & Cosmetics 2023年第4期8卷 6-11页

作者： Rita Bao ChemLinked REACH24H Consulting GroupChina

1 Introduction to recombinant collagen1.1 What recombinant collagen is?In the cosmetics industry,innovation is largely driven by breakthroughs in ***,many brands have achieved significant success by harnessing the potential of exclusive *** include Pro-Xylane for L’Oréal,nicotinamide for Olay,***,recombinant collagen is the rising star in the cosmetics *** widely exists in tissues such as skin,bones,and *** supportive,reparative,and protective properties make it a vital substance in maintaining skin elasticity and *** ***-the father of collagen,stated,the skin aging process is the process of collagen breakdown and ***,how to supplement the continuous loss of collagen has long been a focus of dermatological research.

关键词： Market Collagen breakthrough

Design Innovation and Practice of“One Stationwith One Landscape”for High Speed Railway Stations

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Chinese Railways 2022年第1期 24-31页

作者： SUN Xing CAO Yonggang ZHANG Ting Architectural Engineering Design and Research Institute China Railway Engineering Consulting Group Co.Ltd. China Railway Engineering consulting Group Co.Ltd.

Since the founding of New China,railway station design has experienced a long development and evolution process,and has now developed to the fourth generation,which is called the New Era Railway *** by the new concept of building up a“well-connected fully-integrated,envionmeni-friendly passenger-oriented,economic-efficient,culturally-rich,intelligent and convenient”station,the station building becomes more personalized and specialized displaying distinctive effects,and the design connotation of“one station with one landscape”has also been widened and deepened From the simple differentiated design of facade image,the design is gradually becoming station-specific and customized with station-city integrated development and passengers'boarding and alighting feelings as the *** purpose is to make the station truly become a prominent card and landmark building that facilitates city development.

关键词： high speed railway high speed railway stations one station with one landscape overall design

Pumpability of Manufactured Sand Self-compacting Concrete

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Journal of Wuhan University of Technology(Materials Science) 2023年第6期38卷 1382-1390页

作者： LI Huajian HUANG Fali TU Haifeng SUN Deyi WANG Zhen YI Zhonglai YANG Zhiqiang XIE Yongjiang Railway Engineering Research Institute China Academy of Railway Science Corporation LimitedBeijing 100081China School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China China Railway Engineering Design and consulting Group Co. Ltd Beijing 100055China

By the addition of superplasticizer and air entraining agent,manufactured sand selfcompacting concrete(MS SCC)with slump flow varying from 500 to 700 mm and air content varying from 2.0%to 9.0%were prepared and the pumpability of MS SCC was studied by a sliding pipe rheometer(Sliper).According to the Kaplan’s model,the initial pump pressure and the pump resistance of MS SCC were ***,rheological properties including the yield stress and the plastic viscosity of MS SCC were measured by a *** experimental results show that the increase of slump flow contributes to a higher pumpability and a proper air content,i e,6%is beneficial for the pumpability of MS *** to the existence of stone powder and stronger angularity of MS,the initial pump pressure of MS SCC is only about 60%-88%that of river sand(RS)SCC with the same slump flow and air content,indicating that MS SCC possesses a higher pumpability than RS SCC.

关键词： manufactured sand self-compacting concrete pumpability sliding pipe rheometer rheology

A MODEL AND AN ANALYTICAL METHOD FOR CONVEYOR SYSTEMS IN DISTRIBUTION CENTERS

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Journal of Systems Science and Systems Engineering 2010年第4期19卷 408-429页

作者： Ying WANG Chen ZHOU Manheim consulting USA Stewart School of Industrial and Systems Engineering Georgia Institute of Technology USA

The design and operation of high volume conveyor systems in distribution centers are important due to its high cost, large footprint and critical role in the system. However, there is no analytical model available. In this paper, we study the characteristics of the conveyor sortation system, develop a generic model of a complex conveyor network. We then use the Delay and Stock abstraction to develop an approximate analytical method using sample path analysis and dynamic network flow model. The decision variables include length of accumulation segments and the speeds of conveyor components aforementioned decision variables. This analytical solution provides faster analysis, insights and useful subgradient with respect to the decision variables.

关键词： Conveyor system sortation system network accumulation sample path analysis dynamic network flow