Sharif Digital Repository

The numerical modeling of engineering contact problems is one of the most difficult and demanding tasks in computational mechanics. Frictional contact can be observed in many problems; such as: crack propagation, metal forming operation, drilling pile etc. The thermodynamic coupling problems arise naturally in many industrial processes, such as thermal protection structures ,nuclear fuel elements, layerd structures , heat exchanger as well as metal forming. In these situations predicting temperature field as well as the stress field is of considerable applied importance. When two or more bodies are forced to contact whit each other as a result of thermal or/and mechanical load thermodynamic... 

In Private Equity funds, the manager (known as general partner) collects funds from the investors (known as limited partners) and invests them over a certain time horizon. Assuming that both parties seek to maximize their interests, a situation arises in which the manager does not consider the best interests of the investors. The manager's compensation package is one of the important parts of corporate governance, which consists of four components: management fee, performance based fees (or carried interest), hurdle rate and proceeds distribution method. In this research, first by conducting a semi-structured interview with 15 experts in the PE ecosystem and publishing a questionnaire, the... 

Various composite friction materials containing 40 vol.% organic binder (phenolic resin plus styrene-butadiene-rubber (SBR)) with varying phenolic-resin/SBR ratio were prepared. The content of phenolic resin in each composite was indicated by the resin value (RV) index ranging between 0-100%. The composites with RVs greater than 50% form resin-based friction materials in which the primary binder is the phenolic resin. For RVs less than 50%, the composites become the rubber-based materials where the primary binder is the SBR. The analysis of mechanical properties exhibited that the conformability of the composites increases upon incorporation of SBR. The frictional analysis revealed that type... 

Structural response to near fault ground motions has received significant attention in recent years. Such ground motions are different from ordinary ones and are characterized by a large, long period, velocity pulse caused by the forward directivity. These velocity pulses could potentially impose sever demands on structures and increase their risk of seismic collapse. The situation could even be worse for tall buildings with fundamental periods close to the period of the velocity pulses, and requires special consideration in design process. Prediction of seismic-induced collapse potential of structures has been among the main concerns in Performance Based Earthquake Engineering (PBEE). The... 

Successful performance of forward heuristic planners in classical planning, has motivated the use of forward heuristic search in many temporal planners. Most of forward temporal planners are decision epoch planners that use an explicit representation of time and schedule actions while searching. However, decision epoch planners aren’t complete and cannot solve certain temporal problems with required concurrency. In this dissertation, we present ATFP, a forward temporal planner that does not use an explicit representation of time. In ATFP, duration of actions are temporarily ignored, and a causally valid order of beginnings and endings of actions is searched using classical forward heuristic... 

In this thesis, combustion of liquid fuel spray under the condition of hot and diluted oxidizer, has been investigated. To this end, a novel type laboratory-scale test rig was designed to study the physics governing the MILD-Spray combustion conditions with an applied approach. The underlined test rig eliminates the operational problems of its predecessor test stands and is used for a heavier fuel with much more complex chemical composition (kerosene). The test section is axially symmetrical, in which the fuel is injected by a pressure-swirl atomizer in the direction of hot and diluted co-flowing air. With the use of the aforesaid test rig, the effect of variables such as oxygen...