Introduction: Drip irrigation in which water is only available to the plant, is increasingly used in recent years. Since the flow behavior inside the emitter is difficult due to their complex structure and small size, in present study an attempt was made to assess the flow behavior of the emitters using mathematical and physical models. It needs to be mentioned that analysis of flow behavior of water in labyrinth channels is difficult because of micro-characteristics of the emitter. In this context Zhang et al. (2007) modeled the emitter’ s flow path using fluent Software. In this investigation two physical models namely: laminar and turbulent were used to simulate the flow. Also numerical models that have been tested in experimental conditions, were used in the hydraulic analysis of Emitters. Next, Fluent Software was used to simulate the behavior of the flow inside the two long-path emitters for calculating the discharge-pressure relationship of the models and results were compared with results obtained from experimental results...

Throughout the history of Software engineering, the existence of Software defects at the heart of a system and lack of proper treatment before operational use has always led to serious personal and financial disasters. A test that can provide an appropriate coverage at the code-level of Software can prevent many of these incidents. The basis path test is considered as the strongest coverage criterion in the white Software box test. The prerequisite for a basis path testing is to have a set of test paths. The greater the number of test paths to be scanned, the greater the amount of Software source code that will be covered and so more Software holes will be discovered. As a result, a basic challenge before running a Software path test is to produce the maximum test paths that can be scrolled. So far, some work has been done to maximize the number of scrollable test paths, including the GSO method, but the results indicate that the number of test paths can be greater than currently achieved. In this paper we have proposed a method to achieve this goal by a hybrid solution based on two evolutionary genetic and birds algorithms. The results of evaluations show that using the proposed solution has led to an increase in the number of scrollable test paths up to 91% comparing with the GSO method.

Despite the success and versatility of mesh based methods --finite element method in particular- there has been a growing demand in last decades towards the development and adoption of methods which can eliminate using the mesh, i.e. the so called meshless or mesh-free methods. Difficulties in the generation of high quality meshes, in terms of computational cost, technical problems such as serial nature of the meshgeneration process and the urge of parallel processing for today’s huge problems have been the main motivation for the implementation of new researches. Apart from these, the human required expertise can never be completely omitted from the analysis process. However, the problem is much more pronounced in 3D problems. To this end, many meshless methods have been developed in recent years among which SPH, EFG, MLPG, RKPM, FPM and RBF-based methods could be named. The exponential basis functions method (EBF) is one of these methods which has been successfully employed in various engineering problems, ranging from heat transfer and various plate theories to classical and non-local elasticity and fluid dynamics. The method uses a linear combination of exponential basis functions to approximate the field variables. It is shown that these functions have very good approximation capabilities and their application guarantees a high convergence rate. These exponential bases are chosen such that they satisfy the homogenous form of the differential equation. This leads to an algebraic characteristic equation in terms of exponents of basic functions. From this point of view, this method may be categorized as an extension to the well-known Trefftz family of methods. These methods rely on a set of the so called T-complete bases for their approximation of the field variables. These bases should satisfy the homogenous form of the governing equation. They have been used with various degrees of success in a wide range of problems. The main drawback of these methods –however- lies in the determination of the basis, which should be found for every problem. This problem has been reduced to the solution of the algebraic characteristic equation in the exponential basis functions method. The method is readily applicable to linear, constant coefficient operators, and has been recently extended to more general cases of linear and also non-linear problems with variable coefficients. The relative performance of usual programming languages such as C++in comparison with mathematical Software packages -like Mathematica and/or Matlab- is one of the major questions when using such packages to develop new numerical methods. This can affect the interpretation of the performance of newly developed methods compared to established ones. In this paper, the implementation of the exponential basis functions method on various Software platforms has been discussed. C++and Mathematica programming have been examined as a representative of different Software platforms. The exponential basis function method is implemented in each platform, using various options available. Results show that with a proper implementation, the numerical error of the method can be decreased considerably. Regarding the results of this research, optimal implementations of C++and Mathematica platforms, error ratio is between 2.5 and 6, respectively.

The Software testing process is very time-consuming and expensive and accounts for almost half of the cost of Software production. The main issue in the test data generation process is determining the program's input data in such a way that it meets the specified test criteria. In this research, the structural method has been used to automate the process of generating test data, focusing on the criterion of covering all finite paths. In the structural method, the problem becomes a search problem, and metaheuristic algorithms can be used to solve it. The proposed method is a hybrid algorithm in which the q-learning algorithm is used as a local search method within the structure of the Coati search algorithm. The results of the tests have shown that this method for generating test data is faster than many metaheuristic algorithms and can provide better coverage with fewer evaluations. On average, our proposed algorithm shows about 25-30% improvement in coverage compared to other algorithms, which makes it significantly more effective than other algorithms. This shows that our algorithm achieves superiority over other compared algorithms due to its more efficient and optimal path coverage approach.

One of the obvious reasons for most disorders in network service provisioning is network path congestion. Congestion avoidance in today's networks is too costly and sometimes impossible. With the introduction of SDN, centralizing the equipment's control plane has become possible. This paper presents an enhanced method named ESV-DBRA to avoid congestion in multi-tenant SDN networks. At first, ESV-DBRA monitors the traffic load and delay of all network paths for each tenant individually. Then, by merging the parameters obtained from the monitoring, the Service Level Agreements (SLA), and a novel proposed cost function, it calculates the cost of the network paths per tenant. As a result, traffic for each tenant is routed through the path/paths at the lowest possible cost from the tenant's perspective. Next, the bandwidth quotas will be calculated and assigned to the tenants over their optimal routes. Afterward, whenever congestion is likely to occur in a path, ESV-DBRA automatically changes the route or bandwidth of the tenants' traffic related to this path to avoid congestion. Related algorithms are also proposed.Eventually, simulations show that the proposed method effectively increases bandwidth utilization by 10.76%.

The linkage between sustainable agriculture, poverty and agricultural extension efforts and their impacts on rural centers in Behbahan Shahrestan has been discussed in this paper. Data were collected from 200 farmers in 40 villages of this Shahrestan. A multi-stage stratified random sampling technique was used for selecting villages and farmers. The findings of path analysis in three different causal models provide the complexity of relationships between variables and environmental degradation so that there is a causal relationship between poverty and unsustainability. Lack of direct causal effect of use of technology and extension efforts on sustainability in three models indicated the structural and institutional limitations of extension in diffusion of appropriate technologies. Finally, recommendations regarding regional planning with respect to socio-economic characteristics and changing from TOT approach to other alternatives and revising the education programs of extension agents are provided.

A B S T R A C TThe present study was conducted to investigate the factors affecting improving the quality of urban housing. This research is applied in terms of purpose and in terms of descriptive-analytical method. The statistical population of the research was the residents of 8 residential complexes of Atabak neighborhood in District 15 of Tehran. Based on Cochran's formula, 384 questionnaires were distributed among residents. Finally, 380 complete and error-free questionnaires were collected. The data collection tool was a questionnaire, the validity of which was verified in the form of face and face validity, as well as divergent validity and reliability of the questionnaire using Cronbach's alpha and composite reliability. Analysis of data and information was done using SPSS and PLS Software. The findings of this research showed physical quality with a path coefficient of 0.368, the variable of access to urban services with a path coefficient of 0.339, the variable of housing social conditions with a path coefficient of 0.169, and environmental quality with a path coefficient of 0.302 has a positive and significant impact on housing quality. According to the path coefficient obtained for the research variables, the amount of their impact on housing quality is evaluated as average. Among the identified factors, the factor of physical quality with a path coefficient of 0.368 has the most significant impact, and the factor of access to urban services with a path coefficient of 0.339 is ranked second. Also, this factor has a positive and significant effect on the physical quality factor of housing.Extended AbstractIntroductionAtabak neighborhood is one of the neighborhoods of District 15 of Tehran. In this neighborhood, physical changes have been made according to the interventions of the Tehran municipality in line with the implementation of the urban landscape plan and organized (inflow of private sector capital) in different years so far. Along with these interventions, the inadequacy of infrastructure and services to meet the population's needs has become this neighborhood's basic problem. Attention to its qualitative aspect needs to be addressed. This matter is important from the point of view of providing the city's basic needs, equitable distribution of facilities and resources, reducing urban inequalities, improving economic-social indicators, preventing unbridled and unplanned expansion, and ultimately improving the quality of life of the people. It demands that the quality of housing and the factors affecting it be evaluated and that a double effort be made to improve it, and it can provide a suitable context for providing suitable models of housing quality for citizens. Considering the mentioned cases, this research aims to answer the question:- What are the effective factors in improving the quality of housing? MethodologyThe current research is descriptive-analytical. In terms of purpose, it is in the category of applied research. Two library and field methods have collected the information needed for this research. In the field method, primary data collection has been done according to the research questions by designing a 5-scale Likert scale questionnaire. The statistical population of the study was the residents of Mobaat, Minabi, Atabek, Shahrak Sajjadieh, Yas, Zahid Gilani, Shahid Asadi, and Safa residential complexes located in Atabak neighborhood of District 15 of Tehran. The statistical population was equal to 20469 people, and based on Cochran's formula, 384 questionnaires were distributed among residents. Finally, 380 complete and error-free questionnaires were collected; the validity of the questionnaire was confirmed in the form of face and face validity as well as divergent validity. In order to check the reliability of the questionnaire, Cronbach's alpha and combined reliability were used, and according to the results presented in the research findings section, the reliability of the questionnaire was confirmed. The data obtained from this research were analyzed using structural modeling using SPSS and PLS Software. Results and discussion This research showed that physical quality has a positive and significant effect on improving housing quality; according to the value of the obtained path coefficient, which is equal to 0.368, the value of this effect is considered moderate. Based on the results, it can be said that physical dimensions, such as the physical crystallization of housing, are the most objective and material issues in housing evaluation, analysis, and planning. Concerning the impact of access to urban services on the quality of housing, the findings indicated a significant impact of access to urban services. In explaining the results of this section, it can be said that gradually, the housing is changing from a single purpose to a shelter. Those other aspects of welfare and social comfort are also added; the limits of enjoying services and access to the essentials of life are shown to evaluate the housing quality. These indicators are very important in determining housing quality and are an integral part of housing planning. Access to urban housing services is considered one of the main indicators of life, which the Population Crisis Committee has used to measure quality in the world's metropolises. In relation to social conditions and environmental quality on the quality of housing, the results of this research confirmed the impact of the social environment and environmental quality on the quality of housing. Creating residential spaces is a topic that has been discussed previously. From the beginning, human beings have tried to create a favorable living environment that matches the quality conditions of their residence's social and environmental environment. ConclusionThis research was written to explain the factors affecting improving the quality of urban housing. The findings of this research showed that among the studied factors, the physical quality factor with a path coefficient of 0.368 has the most significant impact on improving the quality of urban housing in Tehran, such that this factor can explain 13.5% of the variance of the housing quality condition variable. Physical quality is defined based on the structural basis of a building and is often defined in the form of rules and standards related to it. The physical quality is sometimes interpreted as the appearance of buildings. Since they are fixed and real things, they are the reason for the emergence of general indicators for housing evaluation. The second factor is access to urban services with a path coefficient of 0.339, so this factor can explain 11.4% of the variance of the housing quality condition variable. This factor has been ranked second regarding the impact on housing quality according to the path coefficient value obtained. In third place was the factor of environmental quality with the path coefficient value of 0.302, and this factor can explain 1.9% of the variance of the variable of housing quality. Moreover, in the last place is the factor of housing social conditions, which has a path coefficient of 0.196. Also, from the other results of this research, we can mention the positive effect of access to the quality of urban services on the improvement of the physical condition of housing, and the value of the path coefficient obtained for this effect is equal to 0.623 so that it is 38.8% of the variance of the variable. FundingThere is no funding support. Authors’ ContributionThe authors contributed equally to the conceptualization and writing of the article. All of the authors approthe contenttent of the manuscript and agreed on all aspects of the work declaration of competing interest none. Conflict of InterestThe authors declared no conflict of interest. Acknowledgments We are grateful to all the scientific consultants of this paper.