فهرست مطالب razavian

When comminution precedes mineral beneficiation processes, the liberation spectrum of the particles in a comminution process is of great importance. The calculation of the liberation spectrum in a continuous closed milling circuit is a vastly more difficult task. Here, a method has been incorporated into the CMCS simulation software to calculate the product size distribution and liberation spectrum in ball mills. The model requires a minimum amount of experimental data and is capable of calculating the detailed liberation spectrum. While, other existing methods account only for the completely liberated particles and a broad group of unliberated particles are not represented. An easy-to-use ball mill simulation environment has been developed and the results are compared with measured grinding data and previously existing simulators, particularly MODSIM, demonstrating firmly tested performance both in terms of accuracy and precision of obtained results.

Multi-objective optimization is the simultaneous consideration of two or more objective functions that are completely or partially inconflict with each other. The optimality of such optimizations is largely defined through the Pareto optimality. Multiple objective integer linear programs (MOILP) are special cases of multiple criteria decision making problems. Numerous algorithms have been designed to solve MOILP and multiple objective mixed integer linear programs. However, MOILP have not received the algorithmic attention that continuous problems have. This paper uses the data envelopment analysis (DEA) technique to find a well-dispersed non-dominated vectors of multiple objective mixed integer linear programming (MOMILP) problem with bounded or unbounded feasible region, while the previous methods consider only problems with bounded feasible region. To this end, it uses the L$_1-$norm and the modified slack-based measure (MSBM) model. The proposed method does not need the filtering procedures and it ranks the elements of well-dispersed non-dominated vectors of MOMILP problem. The proposed algorithm is illustrated by using two numerical examples.

Some existing patterns of urban development and human activity have led to the disorder environmental regulation and remnants of the human species and the sustainability of life on Earth have faced with serious threats.This study examines the relationship between mixed land use in urban and different dimensions of environmental, social and economic aspects in sustainable development. Many features in mix use in the city is related to the quality of life in cities like the availability of urban services and facilities, clean environment, pedestrian travel, the reduction of the cost of fossil fuels, elimination of the use of private vehicles, and public transportation that promote social interaction that can facilitate to attain city sustainable development. Metodology in this research is descriptive – analytical. In this Research the mixed uses for region 1 of Tehran is divided into three classes: the mixed center, mixed axises and mixed arena. Then it is discussed about the role of this land use for regional sustainable development. The Research results show that to achieve sustainable development In terms of social, economic and environmental dimensionsWould be practical in the mixed use form.

The combined system of gate and weir is used for flow measurement in open channels. But in case the passing water has floating material and sediment it damages their performance and hence error of measurement will increase. In order to solve this problem، weir and gate can be combined and a concentrated hydraulic system known as weir-gate can be developed، thus allowing sediments transportation from under the gate and floating particles on weir. The principal goal of this study was to investigate the passing flow characteristics by trapezoidal weir and sharp-edge rectangular sluice gate in rectangular channel، and also suggest a discharge coefficient for combinational flow in different flow conditions. The experiments were carried out in laboratory channel on models with different geometric dimensions under various hydraulic conditions. Discharge coefficient was presented for various condition of passing flow of trapezoidal sharp-edge weir and below rectangular sluice gate using statistical analysis conducted on dimensionless geometric parameters affecting the flow. Resulting discharge coefficients were in agreement with laboratory results.

Many devices and methods are available for the measurement and control of flow rate in open irrigation channels. Among, these devices, sharp crested weirs and sluice gates are commonlyused. In order to minimize the disadvantages of weir and gate, they can be combined together in one device yielding a simultaneous flow over the weir and below the gate. In this study the hydraulic characteristics of combined device of weir-gate such as coefficient of discharge and effective parameter on simultaneous discharge were investigated. The relationship between the experimental and theoretical results of the geometric and hydraulic parameters in the function of the flow statistically was analyzed and a coefficient discharge for combinational flow was presented. The error from the application of equation for 95% of data was ±2.5 percent.

The aim of this study is friction modeling and optimization of a “vibration modal analysis simulator”. This device has been used for observation and measurement of natural frequencies and mode shapes ofvibrating components and parts under the free or forced vibration conditions. In this paper to obtain linear vibrating motion with less measurement errors and optimum friction factor، the new prototype has been designed using the genetic algorithm. Mass linear motion is modeled by viscous friction agent so that optimized friction factor C with six sub-designation factors is calculated. Obtained results with respect to precursor’s availability، fabrication ability and from the economical point of view are more amenable and applicable than the preliminary devices and show a 70% reduction in friction factor.

In this research, residual strength and stress concentration factor of laminated composites with a circular open hole are studied analytically, numerically and experimentally. The numerical study was carried out using the finite element method. Moreover an analytical study was carried out with developing of point stress criterion. Mechanical testing was performed to determine the un-notched tensile properties and notched strength of composite laminates and characteristic length to reinforcement of the notched strength of composite laminates are determined. Results show that the influence of specimen dimension, notch size, lay ups and material properties are important on residual strength and stress concentration factor of laminated composite materials.

To believe some teachings of christiandom and church is one of muslim scholar's disturbances among Islam and christian arguments. Some of them including Holy trinity, sacrifice and eternal sin, are intruced as polytheism in Islam. Christians believed those teachings completely in the post centuries, but some christian thinkers analyzed and criticized them in the recent centuries. Some didnt accept although some interpreted it. Muslim thinkers, on the other hand, entered this discussion interpretingly, considering the religion's relationship. In this essay, some verses of Maryam (As) surah are described while introducing both viewpoints. Maybe it is a new way to know Jesus christ's (P.B.O.H) character better. He was Saint Mary's (As) son, also he was a prophet like other prophetshaving special characteristics and an especial birth. But he was not the God's son.

Nowaday, many city officials know essential to Review in Management methods in cities of country. Despite the long history of urbanization and traditional patterns of Iran, follow from patterns of centralized planning and management no has Possible Social capital involvement in urban governance that leading to ignoring programs beneficiaries and ultimately failure to plannings. In new attitude of urban planning emphasize on bottom-up approach and the empowerment of urban neighborhoods. This method deal with specific dimensions of neighborhood space-scale rather than macro attitude and subjective scales approach. With the transition from governcentric urban planning with general attitudes toward socialcentric planning can be hoped that using social capital for sustainable in the city moved. Social capital through the hegemony of public reason and wisdom that is in the form of horizontal communication networks makes it easy to achieve team goals. Indeed the face and problems solve That modern cities are involved with correct and optimal use of talent and ability of citizens in framework of relations network is achieveable. Region 12 of Tehran, located in the city's historic core and due to the long history terms of physical and social structure is different from the region1 of Tehran that In the process of expansion of Tehran due to the geographic location Receptive have a population with Superior economic and social base. The purpose of this research compared social capital in both Regions 1 and 12 of the city of Tehran. Research method is descriptive and analytical that the used from Fisher text and spss software. The research hypothesis states that social capital in Region 12 will indicates a higher level of Region 1. Although it is approved in the present research that the level of bounding social capital is higher in Region 1, the score obtained in bridging social capital factor is higher in Region 12.

Nowadays Laparoscopic Cholecystectomy is known as a gold standard method for Cholecystectomy. This study was done to evaluate outcomes of the surgery in the first admitted group of patients in Qom Golpaegani hospital. Methods All patients that had been treated by Laparoscopic Cholecystectomy during 2005-7 were included in this retrospective survey. Study population was consisting of 305 cases with age between 15 to 86 years old %64.9 women and 35/1% men and 80% with symptomatic gallstones. Data were collected using questionnaire and then analyzed using SPSS software. Results In 2007 multiplicity of Laparoscopic Cholecystectomy was the highest. The mean operation time was 45 min and duration of hospitalization was 12-48 hours. %80 of all cases (both men and women) had symptomatic gallstones which had been determined by sonography and others had acalculous Cholecystitis. The most common complication during operation was bradychardia as a result of gas flow into the abdomen. There was no case of death. Conclusion Our results showed that Laparoscopic Cholecystectomy is a standard method of Cholecystectomy and have a desirable outcome.

In this paper we have focused on the dielectric constant effect between various solvents with theoretical modelin the biochemical process. Thereby, AAA, UUU, AAG and UUC triplex sequences have been optimized inwater, methanol, ethanol and DMSO with proposed SCRF Model of theory. The solvation of biomolecules isimportant in molecular biology since numerous processes involve to interacting a protein with changing ofsolvent-molecule.The hydrogen bond is one of the important predictions of structural and functional in biochemical andbiophysical of biological complexes such as proteins. mRNA-tRNA pairing as a fundamental step in protein synthesis is a complexes process controlled by hydrogen bonding between two anti-parallel trinucleotides,namely the mRNA codon and the tRNA anticodon.In order to determine the optimized structural biology including of bond lengths, bond angles and dihedralangles energies, dipole moments and other properties of codons and anticodon, we have performed ab initiocalculations of Quantum Mechanics (QM) at HF/sto-3G, 3-21G, 6-31G levels in gas phase and a few solventswith different dielectric constans via the SCF method using the GAUSSIAN 98 software package. Optimizationat the HF/6-3 1G level has yielded results in better agreement with the experimental data.