Due to the growing demand of cellular networks, the need to increase the capacity of these networks has always been a challenge. Heterogeneous cellular networks using small base stations alongside macro base stations are low cost and effective solutions for this problem. However the differences between the various BSs in heterogeneous networks have created new challenges in terms of cell association and interference management compared with the traditional cellular networks. Therefore, the design of new and efficient methods for allocating cells and resources in these networks is an open research topic. This paper addresses the need for an efficient solution to simultaneously allocating cells and subbands in order to prevent interference for all users. The protocol interference model and its modeling methods in cellular networks have been studied. After modeling the system, the problem is formulated as an integer optimization problem. Then, by reformulating the problem and using a one-level dual decomposition, an algorithm with efficient complexity with near-optimal answers is attained. Thereafter, a distributed protocol is presented in which each user and each base station would only require local information for making decisions. The simulation results confirm the effectiveness of the proposed solution.

Despite the importance of the perception behind teachers' feedback, it is astonishing to note that there are not many studies regarding how teachers provide feedback. Drawing upon Ellis’ (2009) typology of written Corrective Feedback (CF), this study explored the most common feedback types provided by EFL teachers. Moreover, the study aimed at finding out whether teachers’ teaching experience and learners’ proficiency level had any bearing on the type of feedback the teachers provided. Eleven teachers provided feedback on 301 descriptive essays written by EFL students in English. The findings revealed that teachers mostly tended to employ direct CF to correct their students’ linguistic errors. This was followed by indirect CF and metalinguistic CF, respectively. It came to light that focused CF, electronic feedback, and reformulation had no popularity among Iranian EFL teachers. The experienced teachers opted more for indirect feedback while the inexperienced ones preferred direct feedback.  Teachers were more inclined to provide intermediate students with direct CF whereas they provided more indirect CF to the upper intermediate students. The results suggest that not all teachers’ perceptions about feedback can necessarily be rendered into classroom practices and various factors, including culture, society, learners and teachers themselves impact teachers’ beliefs and practices.

Frying oils undergo quality changes due to long term heating at high temperature in the presence of oxygen and moisture.The aim of this study was determination of fry-life of two formulated frying oils produced in pilot scale. After determination of physical and chemical characteristics of primary oils, two formulations, i.e. formula 1 or F1(palmolein and sunflower oils 50:50)and formula2 or F2(palmolein, sunflower and cottonseed oils 50:25:25) were prepared by blending, then TBHQ(100ppm) and citric acid(100ppm) were added to them.For determination of fry-life potato slices(Agria variety) were fried at a rate of 200g/30 min(180 °C) in a 40-litter fryer, until one of the characteristics(peroxide value or PV, acid value or AV, smoke point, total polar compounds or TPC,Fritest and Rancimat) reached the discard point for frying oil. PV were variable due to decomposition in high temperature and reproducing during cooling of the oils. AV and TPC were increased during frying. The increasing of AV was higher in control, reversely two formulated frying oil,s TPC were more than control. A sample of partial hydrogenated frying oil produced by an Iranian factory was used as control. Oxidative stability of two formulated frying oils and control were determined by Rancimat in 110°C. Oxidative stability of frying oils were reduced during frying as well as smoke point, although this reduction was faster in control,and after 25hrs frying reached the discard point (178 °C). The results of Fritest were not similar to TPC in the last steps. Statistical analysis did not show a significant difference(P<0.05) in the fry-life of F1 and F2(TPC of F1 and F2 were 21 and 20.5 hours, respectively) but there was a significant difference between two formulated frying oils and control(P<0.05). The control was discarded after 26.5 hrs frying. Regarding the frylife, nutritional value(especially trans fatty acid content) and economical aspects(cost of hydrogenation), F1 was the best frying oil(F1>F2>control)and could be suggested as a substitute for hydrogenated frying oils.

The concepts being used in international relations are mostly qualitative، subjective and incalculable. However، in the middle decades of the twentieth century، some efforts had been carried out in order to make some of the concepts and propositions of this field formulated، calculable and statistical. This process suffered serious shortcomings and proved fruitless in making international relations computable. However، making use of mathematical symbols and formulizing the propositions، while knowing the uncertainty of results and being a human related issue، is significant and useful and contributes to better understanding of phenomena in complex conditions. The framework of Game Theory، in the theoretical literature of deterrence is amongst these concerns. In the early years of the twenty-first century arduous endeavors have been made to develop this theory and its models making its concepts and qualitative signs formulized and calculable in the European and American International relations. On the other hand، in recent decades، international relations theories have had a considerable tendency towards involving norms in their literature and analysis. In the present article the authors seek to study the ways in which norms affect and intervene in the field of international relations through symbolizing and formulating these concepts within the new versions of Game Theory. Actually the authors have tried to answer the following question: «When، how and to what extent can norms affect the performance of the countries in international relations?».

In this paper, a new model is proposed to simultaneously consider the facility location problems, retailer assignment, inventory control and routing problem. In this model, the inventory control policy is first determined for retailers with a certain demand and then used as a constant reordering inventory time period for retailers that are located in a single route. The model is formulated as a mixed integer programming problem and, since it is an NP-Hard problem, a meta-heuristic algorithm based on simulated annealing is developed to solve the problem. A lower bound method is proposed for testing and analyzing the results obtained from the algorithm. A number of numerical test problems are solved, and the results for different cases of the problems show that the proposed algorithm is fast and efficient for solving the integrated problems of facility location, routing problem and inventory control in a two-stage supply chain with different dimensions.

In this research, a model of the possible dynamic cumulative size of a single product with random demand and capacity limitations in the production and transportation network has been developed to minimize the total costs of maintenance, start-up, and overtime. In the proposed model, there is a possibility of transferring the launch of goods to the next period, which plays a significant role in reducing the cost of restarting. Static uncertainty strategies and various service level performance indicators are considered to limit the amount of post-drop demand. Common commercial agents have been used. It is demonstrated by the sensitivity analysis of the proposed model and its analysis at the level of different services that it is performing and efficient, and it also provides a more realistic perspective for planning in the face of uncertain demand conditions.

Vendor managed inventory (VMI) is one of the popular strategies to manage inventory control system, in this strategy, the vendor is responsible for controlling and replenishment the inventory of retailers. In this paper, a bi-objective vendor managed inventory (BOVMI) model with fuzzy demand was investigated for a supply chain problem with multiple vendors and retailers, the fuzzy demand is formulated using trapezoidal fuzzy number (TrFN) where the centroid defuzzification method is employed to defuzzify fuzzy output functions. The vendor confronts two constraints: number of orders and available budget and minimizing the total inventory cost and optimizing the warehouse space are the two objectives of the model. Since the proposed model is formulated ino a bi-objective integer nonlinear programming (INLP) problem, an non-dominated Sorting genetic algorithm-II (NSGA-II) has been developed to find Pareto front solution. To improve the performance of algorithm has been calibrated using Taguchi method. Finally, conclusions are made and future research works are recommended.

Development of hydraulic geometry relationships are of great importance in different applications of stream restoration design and hydrological modeling. Accordingly the main objective of this study was to develop regional relationships for bankfull channel dimensions in Tarwal basin using the drainage area as an independent variable. Several fieldworks, focused on Chameh Sis, Sangeh Siah, and Ozon Dareh tributaries as well as the main channel of Tarwal River, were conducted between 4 and 19 November 2015. Twenty two stable-channel cross sections were used to obtain the relationship among the bankfull channel dimensions and the drainage area. The results indicated that piecewise models are the best models for such relations. Simple power regression models were assessed as not suitable models for predicting hydraulic geometry according to the Relative Root Mean Squared Error (RRMSE) values of greater than 0.4. While for the piecewise models the RRMSE values were less than 0.2 for predicting bankfull cross sectional area and width of stable alluvial channels in basins smaller than 1165 km2. Also the RRMSE values were less than 0.12 and 0.25 respectively for predicting mean and maximum bankfull depth of stable alluvial channels in basins smaller than 100 km2. Nevertheless there were no ideal model to estimate bankfull channel dimensions in basins larger than 1165 Km2. This could be a result of significant changes in rainfall-runoff relationships or the influences of anthropogenic disturbances in large basins. The results provided useful data for stream restoration as well as water structure design.

The precision and accuracy of National Research Council (NRC 2001) vs. Cornell Pennsylvania Miner (CPM) softwares were evaluated. Sixteen lactating dairy cows (8 in second lactation and 8 in third, with days in milk of 55 ± 31, body live weight = 641 ± 53 Kg, milk yield =31.2 ± 2.5 Kg/day), were assigned to individual pens in a randomized complete block design, with two blocks of two ration treatments (each treatment including 4 cows in second lactation and 4 in the third). The cows were fed rations formulated by NRC 2001 (A) and CPM (B), as totaly mixed rations (TMR) for 90 days. The adaptation consisted of a period of two weeks from the beginning of the experiment. The average milk yields of cows fed with diet A vs. B were 31.11 and 31.9, respectively with no significant difference observed between the two groups for the mentioned trait (p>0.05). There was no significant difference observed for dry matter intake (DMI) in the two ration treatments (p>0.05), the average dry matter intake of diets A vs. B being 22.9 and 22.33 Kg/day, respectively. Both NRC 2001 and CPM underpredicted DMI (-0.63 and -2.43 Kg/day respectively) while the National Research Council model predicting DMI somehow more accurately (in lactating dairy cows) than CPM. Average daily crude protein intakes for diets A vs. B were 3618 and 3438 g/d, respectively (P<0.05). An economical comparison of formulated rations by NRC 2001 vs. CPM (for the costs of feed per unit milk yield) showed a significant difference (1430 vs. 1250 Rails for NRC2001 and CPM, respectively) (p<0.01). CPM predicted a lower protein requirement than NRC 2001 with no negative effect being observed on milk yield or on any other traits. According to the results of the present study, the use of CPM is recommendable in formulating rations for the lactating dairy cows

This study investigates the problem of electric vehicles routings with a limit on the volume of vehicles capacity. In this regard, the fleet which includes some electric vehicles with given limited battery capacities, should also be taken into account in the planning of distribution. To this end, recharge points are provided in the transmission network to recharge the cars and complete their routes if a battery needs to be recharged. As electric vehicles are only used in the distribution of goods, other aspects should also be considered. One of the important aspects of cargo volume limitation is the relatively low cargo space. Sometimes the goods assigned to a vehicle may be justified by the weight limit but the total volume of goods may exceed the freight volume. Thus, in this research, a mathematical programming model for the problem is presented. Then, several problem instances are designed to validate the model. Then a simulated annealing based algorithm is developed to solve large-scale problems for real world applications.