Evaluation of a self-equilibrium cutting strategy for the contour method of residual stress measurement

An assessment of cutting-induced plasticity (CIP) is performed, by finite element (FE) prediction of the plastic strain accumulation along the cut tip when the EDM wire sections the NeT TG4 weld benchmark specimen along two cutting directions. The first direction corresponds to a conventional (C) cutting strategy, whereby the EDM wire cuts through the thickness of the weld specimen and travels in a direction transverse to the weld. The second direction corresponds to a self-equilibrating cutting (SE) strategy, whereby the EDM wire cuts across the transverse direction of the weld specimens and travels through the thickness of the plate. The cutting thus progresses simultaneously through the compression-tension-compression regions of present weld residual stress (WRS) field. This type of cutting strategy is believed to minimize the CIP by minimising residual stress redistribution during cutting, due to stress equilibration across the sectioned material. The simulated cutting procedures are conducted under a range of clamping conditions to assess whether mechanical restraint has a primary or secondary influence on CIP accumulation. Both predictions of CIP and the resultant back-calculated WRS demonstrate that (i) mechanical restraint is the primary variable influencing CIP development, and (ii) under no circumstance does a self-equilibrating cutting strategy perform significantly better than a conventional cutting approach. The reason that self-equilibrating cuts are not effective is illustrated by calculating the Mode I (KI) stress intensity factor (SIF) along the cut tip, and correlating trends in KI to CIP development

Effects of ultrasonic on microorganisms and enzymes

Removing on pathogens is the key concern of non-thermal technology in food products. Recently, inclusion of ultrasound into the food industry has been a subject of research and development. The application of ultrasound in food industry is undoubtedly the notion of consideration and development and, the same as other cases in other areas, the sound ranges can would fall into the following categories of high frequency, low energy, diagnostic ultrasound in the MHz range and low frequency, high energy, power ultrasound in kHz range. The advantageous application of power ultrasound is reflected in its chemical, mechanical, or physical effects on the process or product. Microorganisms Inactivation mechanism, based on physical and chemical factors that ultrasonic was caused on liquid food. When it comes to physical and chemical effects, one would distinguish between them as thinning cell membrane, localized heat and pressure changes (5500°C, 50Mpa); hydroxyl radical and sonochemical reactions, respectively. Ultrasound-assisted inactivation of microorganisms and enzymes brings about the extension of shelf life of raw materials or prepared foods. The study focuses on the related literature having to do with the effect of ultrasonic on microorganism and enzymes

Evaluation of the Effect of different microwave dryer power on the Qualitative and Quantitative properties of Essential oil of Bakhtiari Savory

Drying is one of the most important post-harvest stages of medical plants which has a significant effect on the quality and quantity of the effective compounds. In order to promote the objectives of the study, microwave power was selected as an independent variable so that power variable microwave was designed and constructed. After collection and drying the savory samples in the shade, the essential oil at different treatments was extracted in three levels of 400, 600 and 800 W. The volatile oil was analyzed using GC/MS method. Results of experiments showed that increase in the power from 400 W to 600 and 800 W caused a reduction in drying time. The most yield of essential oil was obtained in the shade drying method with the essence value of 2.41%. It was also revealed that with increasing the microwave power, the amount of essence decreased, so that the microwave power of 800 W had the lowest essence value. The highest values of thymol and carvacrol and sum of them that show the quality of essential oil was obtained in drying methods with microwave power of 800 W (56.83%). Overall, when the quality of essence is important, the common method of shade drying is suggested, while considering the speed and quality, the microwave drying is recommended

Evaluating Physical Properties of Potato by a Combined Tillage Machine

Abstract: Potato is a complete and cheap food and can be considered as a source of starch. It medical, industrial and other usages have increased its importance. One the most important things about potato from customer's point of view is it appearance. Because its improper shapes raise problems for re-planting and other uses. One of the most important factors that affect shape and other properties of potato is soil preparation practices prior to seeding. Thus through experiments at educational farm located in Khurasegan Islamic Azad University, in form of complete random tests, four treatments of plows, moldboard, chisel, disk, and a new one made by Iran Plow Tools (a combination of chisel and disk plows), in three repetitions were compared. Parts of harvested products from each device's farm were divided and then tested. Through several experiments, skin area averages, tubers weight, tubers size, tubers quantity, and product performance (output) were measured and by a statistical analysis method were compared. In comparing products from moldboard plow and Iran Plow Tools' plow no significant differences were observed in tubers size and product performance, but for tubers quantity and tubers weight averages, the differences were significant. In comparing the new plow with other tested plows for above mentioned factors, mostly the differences were significant. Briefly, the results show that by means of the new combined plow, more uniform products can be obtained and it is a proper choice to replace moldboard plow nationwide. [Nature and Science 2010;8(11):66-70]. (ISSN: 1545-0740)

Artificial neural networks, genetic algorithm and response surface methods: The energy consumption of food and beverage industries in Iran

In this study, the energy consumption in the food and beverage industries of Iran was investigated. The energy consumption in this sector was modeled using artificial neural network (ANN), response surface methodology (RSM) and genetic algorithm (GA). First, the input data to the model were calculated according to the statistical source, balance-sheets and the method proposed in this paper. It can be seen that diesel and liquefied petroleum gas have respectively the highest and lowest shares of energy consumption compared with the other types of carriers. For each of the evaluated energy carriers (diesel, kerosene, fuel oil, natural gas, electricity, liquefied petroleum gas and gasoline), the best fitting model was selected after taking the average of runs of the developed models. At last, the developed models, representing the energy consumption of food and beverage industries by each energy carrier, were put into a finalized model using Simulink toolbox of Matlab software. Results of data analysis indicated that consumption of natural gas is being increased in Iran food and beverage industries, while in the case of fuel oil and liquefied petroleum gas a decreasing trend was estimated