A Comparison of Large Deflection Analysis of Bending Plates by Dynamic Relaxation

In this paper, various dynamic relaxation methods are investigated for geometric nonlinear analysis of bending plates. Sixteen wellknown algorithms are employed. Dynamic relaxation fictitious parameters are the mass matrix, the damping matrix and the time step. The difference between the mentioned tactics is how to implement these parameters. To compare the efficiency of these strategies, several bending plates’ problems with large deflections are solved. Based on the number of iterations and analysis time, the scores of the different schemes are calculated. These scores determine the ranking of each technique. The numerical results indicate the appropriate efficiency of Underwood and Rezaiee-Pajand & Alamatian processes for the nonlinear analysis of bending plates

COVID-19 crisis and resilience of tourism SME’s: a focus on policy responses

the resilience of small and medium-sized tourism enterprises during crisis periods. Proper selection and implementation of these policies is one of the major challenges facing tourism policy makers. The aim of this article is to propose a systematic framework for selecting government supportive policies that contribute effectively to resilience improvements of tourism SMEs during the COVID-19 disaster. After reading the international reports of the COVID-19 disaster carefully and using similar research findings in past disasters as the preliminary stage of framework development, a comprehensive list of country-based recovery policy responses as well as the critical success factors (CSFs) of tourism SMEs in the crisis recovery phase was extracted and then finalized in an expert-oriented process. In the next stage, the Z-SWARA was applied to weigh the CSFs. Then, four Z-MADM methods were implemented to rank the alternatives, and finally, the results were compounded with BORDA technique. The results of implementing the proposed framework in Iran’s tourism industry show that Disaster management planning capability, as well as Marketing management are the most important CSFs. Also, financial support including direct lending and grants and subsidies to SMEs have been identified as the most effective governments’ supportive policies to recover tourism SMEs in the post-disaster phase. Generally, these results have valuable implications for different stakeholders such as policymakers, practitioners and researchers in the tourism industr

3D Object Detection and Tracking Based On Point Cloud Li- brary Special Application In Pallet Picking For Autonomous Mobile Machines

This work covers the problem of object recognition and pose estimation in a point cloud data structure, using PCL (Point Cloud Library). The result of the computation will be used for mobile machine pallet picking purposes, but it can also be applied to any context that requires finding and aligning a specific pattern. The goal is to align an object model to the visible instances of it in an input cloud. The algorithm that will be presented is based on local geometry descriptors that are computed on a set of uniform key points of the point clouds. Correspondences (best matches) between such features will be filtered and from this data comes a rough alignment that will be refined by ICP algorithm. Robust dedicated validation functions will guide the entire process with a greedy approach. Time and effectiveness will be discussed, since the target industrial application imposes strict constraints of performance and robustness. The result of the proposed solution is really appreciable, since the algorithm is able to recognize present objects, with a minimal percentage of false negatives and an almost zero false positives rate. Experiments have been conducted on datasets acquired from a state-of-the-art simulator and some sample scene from the real environment

A multi-attribute framework for the selection of high-performance work systems: the hybrid DEMATEL-MABAC model

Research in strategic human resource management indicates that high performance work systems (HPWS) have a positive impact on the overall performance of an organization as a result of better human resource (HR) outcomes. Regarding the multi-dimensional and complex nature of these factors, common statistical models are not useful for examining the performance of HPWS. Using the capabilities of multi-attribute decision-making (MADM) methods to deal with various criteria that may be contradictory, this study proposes a MADM-based framework that provides the opportunity to prioritize HR practices. Based on this framework, high-performance HR practices and their related HR outcomes were identified after studying the theoretical literature and ascertaining the views of decision-makers and HR experts. Then, after looking at the interactions among HR outcomes, the weights of the criteria were calculated using the method of the decision making trial and evaluation laboratory (DEMATEL). Then, the alternatives were ranked using the multi-attributive border approximation area comparison (MABAC) method. Finally, the designed framework was implemented in an organization active in the banking industry. This framework can be used to improve employees’ performance and, consequently, the performance of the organization. Accordingly, taking into account the resource constraints organizations face, the priorities presented can be helpful in budgeting human-resource-management (HRM) improvement projects and making an appropriate resource allocation for this

Study of antioxidant activity and free radical scavenging power of Physalis alkekengi flower extract

According to the undesirable effects of many chemical preservatives in food products such as oilseed extraction industry, the possibility of substituting these materials with effective compounds of herbal plants have been considered by the researchers. In this study, at first, the Physalis Alkekengi flower extract was extracted by using maceration method with methanol. The Phenolic compounds and the amount of free radical scavenging activity of the flower extract were investigated in different concentrations (200, 400, 600, 800 and 1000 ppm), respectively by Folin–Ciocalteu method and DPPH test and were compared with the synthetic antioxidant activity (BHT) at 200 ppm. The results showed a significant difference between different concentrations of Physalis Alkekengi flower extract, in terms of the rate of Phenolic compounds and free radical scavenging activity of flower extract (p < 0.05). In general, the results of this study showed that the methanol extract of Physalis Alkekengi flower, as a source of cheap and available natural antioxidant, after conducting supplementary experiments can be used in food industry.Keywords: Physalis Alkekengi flower, Free radical scavenging power, Natural antioxidants,Phenolic compounds

Multiple Sclerosis Gene Therapy Using Recombinant Viral Vectors: Overexpression of IL-4, IL-10 and Leukemia Inhibitory Factor in Wharton's Jelly Stem Cells in The EAE Mice Model

Objective: Immunotherapy and gene therapy play important roles in modern medicine. The aim of this study is to evaluate the overexpression of interleukin-4 (IL-4), IL-10 and leukemia inhibitory factor (LIF) in Wharton's jelly stem cells (WJSCs) in the experimental autoimmune encephalomyelitis (EAE) mice model. Materials and Methods: In this experimental study, a DNA construction containing IL-4, IL-10 and LIF was assembled to make a polycistronic vector (as the transfer vector). Transfer and control vectors were co-transfected into Human Embryonic Kidney 293 (HEK-293T) cells with helper plasmids which produced recombinant lentiviral viruses (rLV). WJSCs were transduced with rLV to make recombinant WJSC (rWJSC). In vitro protein and mRNA overexpression of IL-4, LIF, and IL-10 were evaluated using quantitative polymerase chain reaction (qPCR), enzyme-linked immunosorbent assay (ELISA) and western blot (WB) analysis. EAE was induced in mice by MOG-CFA and pertussis toxin. EAE mice were injected twice with 2x10(5) rWJSCs. The in vivo level of IL-4, LIF, IL-10 cytokines and IL-17 were measured by ELISA. Brain tissues were analyzed histologically for evaluation of EAE lesions. Results: Isolated WJSCs were performed to characterize by in vitro differentiation and surface markers were analyzed by flow cytometry method. Cloning of a single lentiviral vector with five genes was done successfully. Transfection of transfer and control vectors were processed based on CaPO4 method with > 90% efficiency. Recombinant viruses were produced and results of titration showed 2-3x10(7) infection-unit/ml. WJSCs were transduced using recombinant viruses. IL-4, IL-10 and LIF overexpression were confirmed by ELISA, WB and qPCR. The EAE mice treated with rWJSC showed reduction of Il-17, and brain lesions as well as brain cellular infiltration, in vivo. Weights and physical activity were improved in gene-treated group. Conclusion: These results showed that gene therapy using anti-inflammatory cytokines can be a promising approach against multiple sclerosis (MS). In addition, considering the immunomodulatory potential of WJSCs, an approach using a combination of WJSCs and gene therapy will enhance the treatment efficacy