Progressive collapse studies generally assess the performance of the structure under gravity and blast loads, while earthquakes may also lead to the progressive collapse of a damaged structure. In this study, the progressive collapse response of concentrically braced dual systems with steel moment-resisting frames was assessed under seismic loads through pushover analysis using triangular and uniform lateral load patterns. Two different bracing types (X and inverted V braces) were considered, and their performances were compared under different lateral load patterns using the nonlinear static alternate path method recommended in the Unified Facilities Criteria (UFC) guideline. Eventually, the seismic progressive collapse resistance of models was compared to their progressive collapse response under gravity loads. These studies showed that models under the seismic progressive collapse loads satisfied UFC acceptance criteria and limited rehabilitation objective. The structures had better performance under seismic progressive collapse than models under gravity loads because of more resistance, ductility, suitable load redistribution, and more structural elements that participated in load redistribution. Furthermore, despite studies on progressive collapse under gravity loads, the dual system with X braces showed better progressive collapse performance (more resistance, residual reserve strength ratio and ductility) under seismic loads than the model with inverted V braces.

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%.

Coronavirus outbreak and its negative consequences have affected not only the Iranian society, but also the international community. The negative consequences of this epidemic it has plunged society into a crisis and epidemic. And this phenomenon, in addition to the relationship between the health of communities, the context of social interactions and some customs (culture) of social activists, as a facilitator of the spread of this virus, which has given it a social and cultural nature. The purpose of this article is to analyze the effects of corona on social sustainability of the worn texture of Urmia city. According to the results obtained from the spatial analysis, we see an unbalanced distribution of service uses that is contrary to the goals of social sustainability. Access to medical facilities is relatively favorable, with 65. 94% of residents having adequate access to Inside tissue facilities and the remaining 34. 06% having adequate access to Out of tissue facilities. In terms of distribution of green and open space uses, the study area is facing a serious problem so that 73. 89% of residents do not have access to such spaces and is facing a shortage of 7. 78 meters per head. but in terms of level and per head, we face limitations. According to the analysis of the questionnaires by the method of path analysis of education indicators (0. 89), quality (0. 62), participation (0. 49), security (0. 35) and justice (-0. 35), respectively, the most Are indicators of social sustainability that have been affected by the Covid 19 virus. .

The common dynamic relaxation algorithm (DR) does not have the ability to trace the static path. In these techniques, the jumps occur at the limit points. A variable load factor is used to fix this defect. Here, a new procedure is suggested to calculate the load factor. The authors’ relationship is achieved by minimizing external work and residual energy, simultaneously. It should be stated that the proposed load factor depends only on the DR artificial parameters. To show the ability of the new formulation, several truss and shell structures with nonlinear geometrically behavior are analyzed. All used methods are ranked by the number of iterations, numbers of convergence points and total duration analysis. Numerical solutions show the high efficiency of the new method. In other words, the authors' technique, in addition to good accuracy, has higher convergence rate, in comparison to the other strategies. On the other hand, the time duration of the proposed method to trace the static paths has been reduced appropriately compared to other techniques.

In the test of a circuit for faults it is very desirable to have the minimum paths that are to be tested for a complete circuit test. At first, the best test vectors are chosen and then these pairs of vectors are applied to the circuit. Each of these pair of vectors is able to detect a certain number of the faults and the path delay fault coverage for each and all of them may be calculated.Suitable choice of a path may result in the coverage of the whole circuit and increases detected faults. In this paper, a new method for choosing the minimum suitable paths is introduced. Decreasing the number of test paths causes an increase in the number of detectable faults by a certain number of test vector pairs, hence giving a better fault coverage. In the presented method, a test path would be selected, if and only if, there exists at least one "two-piece" segment in that path which has not been tested before in the previously tested paths. If the chosen path has at least one "three-piece" (or "more-piece") segment the method will become more complicated. The method is applied to some ISCAS89 benchmarks circuits.

In this paper, a new fast algorithm for path planning and a collision prediction framework for two dimensional dynamically changing environments are introduced. The method is called Time Distance (TD) and benefits from the space-time space idea. First, the TD concept is defined as the time interval that must be spent in order for an object to reach another object or a location. Next, TD functions are derived as a function of location, velocity and geometry of objects. To construct the configuration-time space, TD functions in conjunction with another function named "Z-Infinity" are exploited. Finally, an explicit formula for creating the length optimal collision free path is presented. Length optimization in this formula is achieved using a function named "Route Function" which minimizes a cost function. Performance of the path planning algorithm is evaluated in simulations. Comparisons indicate that the algorithm is fast enough and capable to generate length optimal paths as the most effective methods do. Finally, as another usage of the TD functions, a collision prediction framework is presented. This framework consists of an explicit function which is a function of TD functions and calculates the TD of the vehicle with respect to all objects of the environment.

Multi-robot path planning problem involves some challenges. One of them is the exponential increase in the size of the search space as a result of increasing the number of robots in the operating environment. Therefore, there is a need for algorithms with high computational performance to plan optimal and collision-free paths in a limited time. In this article, a centralized path planning algorithm is presented. The algorithm is a heuristic incremental search, in which the D* Lite algorithm has been adapted for the multi-robot case. The concept of occupancy time has been embedded into the environment model to avoid path interference. A centralized function has been designed to update the environment model and robot data. To evaluate the method, two groups of simulations of static and dynamic types were carried out. The static simulations focused on studying the effect of algorithm parameters, and it was shown that the algorithm can plan paths for up to 40 robots in an environment having 55 percent free space. The dynamic simulations were carried out in Gazebo, a real-time and dynamic physical simulator. The results were compared to a baseline method based on potential fields. The number of robots was increased to 14, and it was demonstrated that for 9 robots and more, the potential field approach either fails or has a rapid increase in computation time, while the proposed method can find feasible solutions in a limited time.

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.