walnuts are one of the most important nut crops worldwide. the area under cultivation increases every year. in 2008, the food and agriculture organization reported exports of about $17.1 billion. the country of iran is the 4th largest producer of walnuts in the world. stages from production to consumption are very important, because the condition and quality of the shelled nutmeats affects the ...

the occurrence of chatter vibrations in boring operation has a great influence in improving workpiece dimensional accuracy, surface quality and production efficiency. in this paper instability analysis of machining process is presented by dynamic model of boring machine. this model, which consists of machine tool’s structure, is provided by finite element method and ansys software. the model is...

the lithologies of regions, which located near the collision zone, are very different from other geology setting. mapping in these areas needs extensive and exact studies and tools because of the variety of rocks, intensive tectonic uplift and complicated units. hyperspectral sensor is one of the most advanced tools with hundreds of bands that each measures a very narrow range of wavelengths an...

background: we aimed to assess the high-risk group for suicide using different classification methods includinglogistic regression (lr), decision tree (dt), artificial neural network (ann), and support vector machine (svm). methods: we used the dataset of a study conducted to predict risk factors of completed suicide in hamadan province, the west of iran, in 2010. to evaluate the high-risk grou...

printing and copying centers have been implicated as an emission source of pollution, and affecting air quality in closed environments. the aim of this study was to measure the btex compound (benzene, toluene, ethyl benzene, and xylenes), and the intensity of electromagnetic fields and the uva ray in photocopy centers in the hamadan city. this descriptive study was done on 45 printing and copyi...

In this paper, using a personal computer (PC), the practical implementation of scalar and vector control methods on a three–phase rotor surface- type permanent magnet synchronous machine drive is discussed. Based on the machine dynamic equations and the above control strategies, two block diagrams are presented first for closed-loop speed controlling of the machine drive/system. Then, the desig...

Introduction: To enhance the dose to tumor, the use of high atomic number elements has been proposed. Objective: The aim of this study is to investigate the effect of gold nanoparticle distribution on dose enhancement in tumor when the tumor is irradiated by typical monoenergetic X-ray beams by considering homogeneous and inhomogeneous distributions of gold nanoparticles (GNPs)...

Usage of flywheel energy storage system (FESS) is a common method for frequency regulation due to its high power injection capacity and long life time. FESS is equipped by two back-to-back inverters including grid-side inverter and machine-side inverter. In conventional method, the machine-side inverter sets the active power and machine flux while grid-side inverter sets the reactive power and ...

Multitasking is an important part of today’s manufacturing plants. Multitask machine tools are capable of processing multiple operations at the same time by applying a different set of part and tool holding devices. Mill-turns are multitask machines with the ability to perform a variety of operations with considerable accuracy and agility. One critical factor in simultaneous machining is to cre...