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The existing loss assessment frameworks in the literature are mainly limited to the evaluation of the expected lifetime seismic losses, and do not assess the probability distribution of the long-term losses. The long-term loss is defined as the cumulative seismic loss of the structures over the service life. However, the probability distribution of the long-term losses can also be informative for decision-making under uncertain seismic consequences. This paper proposes an efficient procedure to calculate the probability distribution of the long-term losses. The procedure is based on the discretization of continuous random variables and performing two sets of recursive convolutions. The... 

A framework for optimal seismic design of structures, considering maximum value as the design objective, is introduced. In this framework, the value parameter incorporates a comprehensive set of performance indicators. Decision indicators are mapped into equivalent economic values and are directly involved in the design process. This approach leads to optimal assignment of the available resources to meet infrastructure requirements. The construction cost and the risk of seismic consequences are considered as the value components. FEMA-P58 methodology is utilized in estimation of the seismic consequences including the repair cost, repair time, injuries and casualties. Endurance Time method is... 

This paper employs the framework of value-based seismic design to optimize the geometrical and mechanical properties of lead rubber bearings (LRBs). An optimization problem is proposed within this framework. Construction cost and seismic consequences are chosen as the value components. Most failure modes of the LRB, such as strength deterioration, axial buckling, and rubber rupture, have been carefully considered in the seismic response. Besides, a new cost function for LRBs is developed from actual isolated building projects. Moreover, the minimum code requirements for lead rubber isolated buildings are formulated as the design constraints. FEMA P-58 methodology is exploited to predict the... 

This paper uses the value-based seismic design methodology to optimize the mechanical and geometrical properties of triple friction pendulum bearings (TFPBs). An optimization procedure is proposed within this methodology. Initial construction cost and lifetime seismic losses are picked as the value components. Extreme failure conditions of the TFPB, less considered in the current literature, such as the uplift and exit failure modes of the curved surface sliders at the end edges, have been carefully considered in the seismic behavior of the structure. Besides, the minimum code provisions and practical limitations (e.g., the critical overturning diameter of sliders) for friction pendulum... 

The value-based seismic design framework is a new design method that efficiently balances the construction resources and the seismic consequences, through reliable evaluation of the building performance at an affordable computational cost. This paper employs the value-based design approach to optimize the cross-section proportions of the steel wide-flange members. An optimization problem is proposed within the framework of value-based design. Construction cost and seismic consequences are selected as the value components. Moreover, the minimum code requirements are formulated as the design constraints. FEMA-P58 framework is exploited for the prediction of the seismic consequences including... 

Recent studies showed that while code-compliant structures can generally protect the safety of the occupants, they may exhibit extensive damages during strong earthquake events. On the other hand, structures are generally designed to satisfy the seismic code requirements with the least initial cost regardless of their life cycle cost. In recent years, value-based design has been considered as an effective alternative for code-based design procedures. In this method, as well as the initial cost of the structure, a comprehensive consequence modeling is performed in the design process. In this paper, for the first time, a value-based design optimization method is developed for seismic... 

The aim of this study is to develop a new simulation procedure of endurance time excitations in which hysteretic energy compatibility is included. Existing methods for simulating excitations consider only amplitude and frequency content of motions and disregard parameters related to cumulative damage of structures. Hysteretic energy consistency, as a cumulative damage-related parameter, is included in the process. The proposed method is applied to generate new excitations. Efficiency of the proposed method is examined in two ways: (1) comparing damage spectra of simulated excitations with recorded ground motions; (2) applying simulated excitations in seismic assessment of three concrete... 

Endurance time method is a dynamic analysis in which structures are subjected to increasing excitations. These excitations are generated to be compatible with ground motions. Conventional excitation generating processes take into consideration the dynamic characteristics related to intensity and frequency contents of ground motions; however, duration-related characteristics have never been considered directly. In this study, the existing methodology is extended to include Cumulative Absolute Velocity as a duration-related parameter in the generating process. These newly generated excitations are then employed to estimate nonlinear responses of three concrete structures as case studies.... 

The endurance time method is a time history dynamic analysis in which structures are subjected to predesigned intensifying excitations. This method provides a tool for response prediction that correlates structural responses to the intensity of earthquakes with a considerably less computational demand as compared to conventional time history analysis. The endurance time method is being used in different areas of earthquake engineering, such as performance-based assessment and design, life-cycle cost-based design, value-based design, seismic safety, seismic assessment, and multi-component seismic analysis. Successful implementation of the endurance time method relies heavily on the quality of... 

Local educational institutions produce in-house English for Specific Purpose (ESP) materials according to the curriculum policies designated and developed by the Ministry of Higher Education In Iran. To this end, this book aims to be used in the Iranian setting at the tertiary level for undergraduate students majoring in Mechanical Engineering. Moreover, the style of English usage in this ESP textbook is American.
Regarding the content of the textbook, it has both thematic organizations in which the topics are relevant and includes sufficient treatment of the target language areas necessary for the students. The principle organizing approach of this textbook is theme-based. In addition,... 

The aim of this study is to employ feedback control loops to provide a stable forward dynamics simulation of human movement under repeated position constraint conditions in the environment, particularly during stair climbing. A ten-degrees-of-freedom skeletal model containing 18 Hill-type musculotendon actuators per leg was employed to simulate the model in the sagittal plane. The postural tracking and obstacle avoidance were provided by the proportional—integral—derivative controller according to the modulation of the time rate change of the joint kinematics. The stability of the model was maintained by controlling the velocity of the body's centre of mass according to the desired centre of... 

A combination of silica chloride and wet SiO2 was used as an effective deacetalizating agent for the conversion of acetals to their corresponding carbonyl derivatives under mild and heterogeneous condition  

Free Content Selective synthesis of conjugated enynes from α-arylalkynols using LiCl-Acidic Al2O3 under solvent-free conditions  

7H-benzimidazo[2,1-a]benz[de]isoquinolin-7-one compounds were prepared in a selective manner by reaction between o-phenylenediamines and appropriate 1,8-naphthalenedicarboxylic anhydrides using acidic alumina under microwave irradiation