Sharif Digital Repository

Iranian women spend a lot of times in the kitchen area in order to have good effects on the family. Unfortunately, we see many of them are suffering from body injuries and particularly musculoskeletal disorders in their middle ages. Many factors cause such problems among which awkward postures are mentioned and with identifying these postures, corrective solutions could be proposed.In this study, firstly, relationship of body injuries with working in the kitchen area is considered, awkward postures are identified and expedient actions are suggested. The aim of this study is chosen designing a suitable task chair for kitchen among the proposed solutions. Then, chair specifications are... 

Sensor Observation Service (SOS) which is defined by Open Geospatial Consortium (OGC) Sensor Web Enablement group is a Web service specification in order to standardize the way sensors and sensor data are discovered and accessed on the Sensor Web. Multiple instances of this service can be implemented around the world, providing huge amount of data every moment. Each of these services operates in specific domain of knowledge (thematic), spatial and temporal dimensions. One way to reveal the underlying data over all of them is to provide an architecture for data integration to allow the user to query sensor data without the knowledge of the infrastructure components. In this research, a novel... 

In this research a joint location- inventory problem is analyzed. We assumed two kinds of inventories: fast-moving and slow-moving goods. These two kinds of goods can be observed in after sales service systems. In the real world fast moving goods are stocked in all dealers but for slow moving goods there is no force to stock in all dealers. Therefore an important decision in these systems is where and how much we should stock the slow moving goods and how each dealer can supplies its demand for slow moving goods. In this research we model this problem as a joint location-inventory model which locates some warehouses in the network to stock the slow moving goods and assigns the dealers to... 

Control and guidance of a vehicle is vital for it to do its mission correctly. Guidance system and decisional algorithms used in it need exact information of instantaneous position, velocity, and attitude of the guided vehicle to determine and issue proper guiding commands.
Estimation algorithms and navigation sensors are two necessary tools for navigation. In the first section of present study, the reentry head equations of motion are derived and a 6-DOF simulation is done for it. In the second section, measurements of sensors will be simulated using results of the first section and existing reference models for sun position vector and earth magnetic field. The third section appertains... 

In the study of heat transfer in micro-channels, free and force convections are two limit cases and these two methods of heat transfer are combined together generally, so to achieve the most accurate informations about the flow field they should be considered in combination. In the first part of the thesis the fully developed slip flow mixed convection in vertical micro-ducts of arbitrary shapes is investigated.Uniform axial heat flux and uniform peripheral wall temperature (H1) is considered. The method considered is analytical-numerical in which the governing equations and three of the boundary conditions are exactly satisfied but the remaining slip boundary condition on the duct wall... 

Less than a decade ago, Test Driven Development (TDD) emerged as a quality assurance approach and applied in agile software developments. In this method, test cases act as software development driver and a new piece of code is added just to satisfy the corresponding test case in the test repository. Although the results of applying TDD show its success in software quality promotion, but the method suffers from some limitations and shortcomings that make its usage hard in complicated and enterprise software projects, particularly in the industry. The goal of the following research is to mitigate the drawbacks of TDD and improve the method in order to make it more applicable for complicated... 

In recent years, advances have been made in the field of miniaturization of the devices (in order to increase their efficiency, lessen the materials needed for the constructions and experiments, reduce costs and energy usage) resulting in the dramatic increase of surface to volume ratio in these devices. This progress has led to the dominance of surface forces which can be used to control very important interface phenomena having a special application such as electrokinetic. Using today’s manufacturing technology; it is possible to construct micro-nanochannels made from different materials such as silicon, glass, quartz, polydimethylsiloxane (PDMS), polymethyl methacrylate (PMMA) whose... 

Target recognition is one of the widespread applications of today's radars that requires obtaining target signatures using radar measurements. High-resolution range profile (HRRP) is one of these signatures that provides a one-dimensional radar image of the target. There are several methods for radar target's HRRP synthesis , all of which require a large bandwidth. One of these methods is the use of stepped frequency radar. One of the advantages of this method is providing a wide bandwidth by sending pulses with small bandwidths, thus obviating the need for broadband receivers and transmitters and making implementation easier. In many cases HRRP of target is sparse, because the number of... 

Optimizing energy consumption in autonomous underwater vehicles (AUVs) to enhance operational endurance necessitates precise ocean current prediction and intelligent path planning algorithms. In this study, real ocean current data were modeled using a hybrid neural network architecture combining two-dimensional convolutional (Conv2D) and long short-term memory (LSTM) layers to forecast the flow field. Based on the predicted currents, an integrated Dijkstra–Genetic Algorithm was employed to determine the optimal path and velocity profile at four distinct depths, considering both scenarios with and without an artificial vortex. The results demonstrate that variations in flow regimes and vortex... 

Both handling and ride comfort play an important role in the performance and quality of a vehicle, and all the vehicle companies in addition to power and transmission system, pays special attention to these properties in the way of improving their products. This thesis is performed with the aim of study on effects of rubber bushing's characteristics of suspension system on handling behavior of a homeland built vehicle (pride). Role angle, slip angle, yaw rate and lateral acceleration are interrelated and are important quantities in studying on handling behavior of a vehicle. We have chosen slip angle as one these quantities and studied on effects of rubber bushing's characteristics on slip... 

This is a theoretical study on heat and mass transfer in electrokinetically driven microfluidic devices with particular consideration to the lab-on-a-chip (LOC) applications. Special attention is given to disclose the effects of the fluid rheology and the aspect ratio of the rectangular geometry on the surface reaction kinetics and the temperature rise due to the Joule heating. Along this line, two different viscoelastic constitutive equations namely PTT and FENE-P models along with the power-law viscosity model are being considered. The secondary aims also include exploring the influences of the fluid properties variations throughout the channel cross section on the hydrodynamic and thermal... 

In this thesis, equations related to large deformation of a polymer were derived by considering viscoelastic effects. To express type of material behavior which includes elastoplastic and viscoelastic property at the same time, two-layer viscoplastic model was used. An axisymmetric model was used for modeling problem in finite element software. By derivation of parameters related to two layer model and entering them in finite element software and also entering other properties required to model the forming process, modeling was performed by special profile connecting input and output sections. Due to favorable properties of spline functions, profiles used in die geometry, were selected from... 

In this project, a ceramic biocompatible coating was applied on Titanium which is included Hydroxyapatite by AC Plasma Electrolyte Oxidation method. First, coating was performed in 5 different solutions and various duration in 500mA/Cm2 as a current density. Then, by microscopic and macroscopic images and size of porosity and also thickness of coat, 3 solutions were chosen for adding nanoparticles: Solution 1 which includes NaH2PO4 and Ca(CH3COO)2 , Solution 3 which includes Ca(CH3COO)2 and Na-Beta G and Solution 4 which includes Ca(H2PO4)2, HMP, NA2(EDTA) and Ca(CH3COO)2 . Also the time 10 minutes was chose as a appropriate time. The average of the porosities size in solution 1 was about... 

Stop-skipping and timetable synchronization in a transit network for subway operation are two effective strategies to reduce passengers' total travel time.Most of the current research on the topic does not consider stop-skipping strategy and timetable synchronization simultaneously. This paper proposes a mixed-integer programming model based on passenger smart-card data concerning the trains' capacity to minimize passengers' total waiting time and in-vehicle time and maximize the number of passengers who successfully reach their destination. Since increasing the number of trains, stations, or the study horizon, exponentially increase the size of the problem, seeking practical methods to...