25 research outputs found

    A Reactive and Efficient Walking Pattern Generator for Robust Bipedal Locomotion

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    Available possibilities to prevent a biped robot from falling down in the presence of severe disturbances are mainly Center of Pressure (CoP) modulation, step location and timing adjustment, and angular momentum regulation. In this paper, we aim at designing a walking pattern generator which employs an optimal combination of these tools to generate robust gaits. In this approach, first, the next step location and timing are decided consistent with the commanded walking velocity and based on the Divergent Component of Motion (DCM) measurement. This stage which is done by a very small-size Quadratic Program (QP) uses the Linear Inverted Pendulum Model (LIPM) dynamics to adapt the switching contact location and time. Then, consistent with the first stage, the LIPM with flywheel dynamics is used to regenerate the DCM and angular momentum trajectories at each control cycle. This is done by modulating the CoP and Centroidal Momentum Pivot (CMP) to realize a desired DCM at the end of current step. Simulation results show the merit of this reactive approach in generating robust and dynamically consistent walking patterns

    Single sample face identification utilizing sparse discriminative multi manifold embedding

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    This paper describes three methods to improve single sample dataset face identification. The recent approaches to address this issue use intensity and do not guarantee for the high accuracy under uncontrolled conditions. This research presents an approach based on Sparse Discriminative Multi Manifold Embedding (SDMME) , which uses feature extraction rather than intensity and normalization for pre–processing to reduce the effects of uncontrolled condition such as illumination. In average this study improves identification accuracy about 17% compare to current method

    Mycobacterium tuberculosis Detection based on mpt64 amplification by Nested-PCR in Sputum samples

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    Introduction: Tuberculosis (TB) is an old problem that is currently considered as a great challenge, mostly in developing countries. It may be a lethal disease. Thus, rapid diagnosis of Mycobacterium tuberculosis (MTB) infection plays a critical role in controlling the spread of TB, whereas conventional methods may take up to several weeks or longer to diagnose the infection. Hence, nested polymerase chain reaction (NCR) assay was applied for direct identification of the MTB DNA presence in sputum samples. The aim of the study was the development of a direct NCR method using mpt64 specific primers for rapid diagnosis of MTB infection. Materials and Methods: To development of study, eight positive and negative sputum specimens obtained from Masih Daneshvari hospital pulmonary TB center, were studied. After smear preparation genomic DNA was extracted and mpt64 was amplified using NCR method. While doing work we paying attention to PCR standardization and precautions to avoid sample contamination. Results: After evaluation gained appropriate results from purified genomic DNA by AGE and biophotometer, the standardized NCR products were evaluated by Agarose Gel Electrophoresis. Five of 7 positive samples were positive, and one of the negative samples was negative using our NCR assay. Conclusion: Based on the results of this study, we could be successful in the NCR technique’s optimization to our system for disese detection, while it can be apply as a more rapid, accurate, inexpensive, and specific diagnostic assay for direct detection of MTB DNA

    Impacts of COVID-19 Pandemic on Micro and Small Enterprises: Evidence From Rural Areas of Iran.

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    peer reviewedSince 2020, the outbreak of the COVID-19 crisis has caused a great deal of social and economic damages to micro and small-scale enterprises (MSEs). This research examined the most common damages of this crisis in active and inactive rural MSEs and also assessed different kind of responses the managers and owners of theses MSEs have received dealing with these damages. The sample population of this study consisted of all managers of 72 active and 38 closed rural MSEs in the Dastjerd village, Hamedan, Iran. These MSEs were mainly garment small factories. This research utilized a mixed approach (quantitative-qualitative) to study the research objectives in depth. First, in qualitative part, semi-constructed interviews and field visits were done. Then, using quantitative, results of the qualitative section, previous studies and the existing literature, a researcher-made questionnaire was created. Based on qualitative part information through interviews, damages of rural MSEs during COVID-19 pandemic were categorized into three classes, including damages related to production, and financial and marketing issues. Also, two categories of managers' responses that could be labeled as passive and adaptive behavior were identified. Findings showed that active rural MSEs have taken more adaptive measures and tried to find appropriate ways to reduce or overcome damages. Active MSEs were mainly owned and managed collaboratively by more literate and experienced managers. Also results revealed that rural MSEs' managers reacted to different kinds of damages based on their ability, knowledge, and experience. Based on research results, managers' knowledge and skills can help them find more adaptive solutions to keep the firms stable and overcome damages. It can be concluded that COVID-19 pandemic has a great impact on rural MSEs and they need more financial support and managerial advice to overcome this kind of crisis situation

    Biological activity (antibacterial, antifungal, antiviral and cytotoxic) of extract from Dysidea spp.

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    Sponges are the most primitive of the multicellular, These organisms don’t have any mechanical defense system, so their early appearance in evolution has given them alot of time for the development of advanced secondary metabolites as chemical defense system. Sponges have the potential to provide drugs from chemical components against diseases. In this investigation the sponge samples, which it is Dysidea spp. , were collected at depth of 15- 20 meter, from locations on the coastline of Island Hengam in Persian Gulf of Iran. For identifying natural components, methanolic and diethyletter were used as extraction solvents, after removal of the solvents, the GC/MS spectra of the fraction were obtained. Then in vitro cytotoxic, antimicrobial, antifungal and antiviral activities were identified. In vitro cytotoxity screening, by XTT assay, against KB/ C152 and HUT-78/ C185 cell line, was conducted in this study in 1 - 500 ”g/ml . IC50 for diethyletter and methanolic extract was 200 ”g/ml in HUT-78 , IC50 for diethyletter extract was 325”g/ml and methanolic extract 325”g/ml in KB. In vitro antimicrobial activity by Broth Dilution Methods against clinical gram-positives and gram negatives (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus و subtilis Bacillus). The results conducted that the MIC values of methanol and diethyletter extract for Escherichia coli 20mg/ml, Bacillus subtilis 10mg/ml and 2mg/ml for Staphylococcus aureus. The MBC values of the diethyletter extracts for Bacillus subtilis 30 mg/ml) and S. aureus aureus 10mg/ml. In vitro antifungal activity by Broth Dilution Methods against clinical pathogens; Candida albicans and Aspergillus fumigatus. The results conducted that the aqueous extracts didn’t have any antifungal activities on pathogens, minimum inhibitor concentrations (MIC) of the diethyletter extract on C. albicans 0/75mg/ml, MFC 5 mg/ml and methanolic extract 0.5mg/ml and MFC 5 mg/ml on A. fumigatus In vitro antiviral activities by XTT assay against MT-2 cell line. The results conducted that IC50 for diethyletter extract 500”g/ml and methanolic extract 475 ”g/ml

    Impact of Supply chain integration on competitive capabilities in Food and Beverages Industries

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    This study examines the impact of supply chain integration (SCI) dimensions on competitive capabilities. For this purpose, the relationship between dimensions of SCI (internal integration and external integration including supplier integration and customer integration) and competitive capabilities (cost, quality, delivery, product innovation) were examined using a conceptual model. The data was collected from top managers of 44 medium and large enterprises of Mashhad Food and Beverages Industries by survey approach. In this study, partial least squares method by Smart pls software and Hulland procedures are utilized to evaluate the measurement and structural models. The results indicated that internal integration is a prerequisite for external integration. The study also revealed that, internal integration and external integration have positive impact on improvement of firms’ competitive capabilities. It was further noticed that, internal integration improves competitive capabilities through external integratio

    An Evaluation of the Adjusted DeLone and McLean Model of Information Systems Success; the case of financial information system in Ferdowsi University of Mashhad

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    Assessing the success of information systems within organizations has been identified as one of the most critical subjects of information system management in both public and private organizations. It is therefore important to measure the success of information systems from the user's perspective. The purpose of the current study was to evaluate the degree of information system success by the adjusted DeLone and McLean’s model in the field financial information system (FIS) in an Iranian University. The relationships among the dimensions in an extended systems success measurement framework were tested. Data were collected by questionnaire from end-users of a financial information system at Ferdowsi University of Mashhad. The adjusted DeLone and McLean model was contained five variables (system quality, information quality, system use, user satisfaction, and individual impact). The results revealed that system quality was significant predictor of system use, user satisfaction and individual impact. Information quality was also a significant predictor of user satisfaction and individual impact, but not of system use. System use and user satisfaction were positively related to individual impact. The influence of user satisfaction on system use was insignifican

    Parent management training used in abusive parent – child interaction in children with ADHD

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    AbstractThe present study examined the efficacy of group positive parenting program, a psycho educational intervention, on abusive parent – child interaction in children with ADHD; participants were mothers of thirty children who met attention deficits and hyperactivity disorder. They were selected from two child and adolescent psychiatric clinics of Tehran and put in to two groups (experimental and control group).their baseline condition was assessed with CTSPC (conflict tactics scale parent- child) .the program of intervention that run for the participant of experimental group had eight sessions, six weekly session of two hours duration plus two telephone session of fifteen minutes, training took over two months. finding for pre and post treatment data indicated the frequency of abusive behaviour of mothers was reduced and one month follow up showed the stable efficiency of the program The results of this program show that we can use this kind of intervention to compensate the lack of information of mothers for solving their problems with their child by no abusive ways and by learning the acceptable behavioural tactics
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