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.

Mass dynamic analysis of structures requires high computational cost which leads to time consuming process. Therefore, it is necessary to use simplified models that significantly reduce the time of the analysis with appro-priate and acceptable accuracy compared to the detailed model. In this research, a simplified model of multi degrees of freedom for the Dual system of moment resisting frame and shear wall with regular plan is proposed. MVLEM model is used for shear wall and Substitute Frame is used for RC moment resisting frame. The MVLEM model consists of axial elements that simulate the flexural behavior of the shear wall and the substi-tute frame uses one bay frame instead of multi-bay moment resisting frames. In the end, the accuracy and speed of modeling and analysis of the simplified model compared to the original model as a detailed frame. The results show that the simplified model provides seismic responses with less than 10% error and analysis time less than 30 times compared to the detailed model.

In this paper, the fuzzy Dual matrix system as e AeX + e B = e C eX + eD in which e A; e B; e C; eD; eX are LR fuzzy matrices is studied. At  rst we solve 1-cut system in order to  nd the core of LR fuzzy solution; then to obtain the spreads of the LR fuzzy solution, we discuss in several cases. The spreads are obtained by using multiplication, quasi norm and minimization problem with a special objective function. We prove some theorems and we suggest conditions in which the fuzzy Dual matrix system of e AeX + e B = e C eX + eD and the fuzzy matrix system of ( e A ⊖ H e C)eX = (eD ⊖ H e B) have the same LR fuzzy solution and we discuss about the conditions where LR fuzzy Dual matrix system has crisp solution. Finally numerical examples are solved to illustrate the ability, accuracy and capability of the proposed method.

Oral and maxillofacial surgery, a multidisciplinary field that intersects with both medical and dental disciplines, is a branch of dentistry encompassing a variety of surgical procedures in the head and neck region. . .

Dual practice is a common phenomen that is considered a challenge for health care system. In this paper, we provide underlying issues about Dual practice it’s, strengths and weaknesses, and methods to manage it. Finally, we propose a solution for Iran.In this review, we have searched electronic databases, models, and government documents about Dual practice of health care workers with “Dual practice” and “health care workers” as key words.Types of interventions categorized in 3 groups: Complete prohibition Dual practice, acceptance Dual practice with some restrictions, Complete acceptance. In Iran acceptance of Dual practice with some restrictions is logic. But Mechanisms of it needs further studies. So revision the 36 article of Fifth Development Plan is recommended.