210 research outputs found

    Analysis of a Signorini problem with nonlocal friction in thermo-piezoelectricity

    Get PDF
    We consider a mathematical model which describes the frictional unilateral contact between a thermo-piezoelectric body and a rigid electrically conductive foundation. The thermo-piezoelectric constitutive law is assumed to be nonlinear and the contact is modeled with the Signorini condition, the nonlocal Coulomb friction law with slip dependent friction coefficient and the regularized electrical and thermal conductivity conditions. The variational form of this problem is a coupled system which consists of a nonlinear variational inequality for the displacement field and two nonlinear variational equations for the electric potential and the temperature. The existence of a unique weak solution to the problem is proved by using abstract results for elliptic variational inequalities and fixed point arguments

    Development of portable automatic number plate recognition (ANPR) system on Raspberry Pi

    Get PDF
    ANPR system is used in automating access control and security such as identifying stolen cars in real time by installing it to police patrol cars, and detecting vehicles that are overspeeding on highways. However, this technology is still relatively expensive; in November 2014, the Royal Malaysian Police (PDRM) purchased and installed 20 units of ANPR systems in their patrol vehicles costing nearly RM 30 million. In this paper a cheaper alternative of a portable ANPR system running on a Raspberry Pi with OpenCV library is presented. Once the camera captures an image, image desaturation, filtering, segmentation and character recognition is all done on the Raspberry Pi before the extracted number plate is displayed on the LCD and saved to a database. The main challenges in a portable application include crucial need of an efficient code and reduced computational complexity while offering improved flexibility. The performance time is also presented, where the whole process is run with a noticeable 3 seconds delay in getting the final output

    Development of a portable community video surveillance system

    Get PDF
    In 2016, a crime rate has been evidently increasing particularly in Kuala Lumpur areas, including reports on house break-ins, car thefts, motorcycle thefts and robbery. One way of deterring such cases is by installing CCTV monitoring system in premises such as houses or shops, but this usually requires expensive equipment and installation fees. In this paper a cheaper alternative of a portable community video surveillance system running on Raspberry Pi 3 utilizing OpenCV is presented. The system will detect motion based on image subtraction algorithm and immediately inform users when intruders are detected by sending a live video feed to a Telegram group chat, as well as sound the buzzer alarm on the Raspberry Pi. Additionally, any Telegram group members can request images and recorded videos from the system at any time by sending a get request in Telegram which will be handled by Telegram Bot. This system uses the Pi NoIR camera module as the image acquisition device equipped with a 36 LED infrared illuminator for night vision capability. In addition to the Python language, OpenCV, a computer vision simulation from Intel is also used for image processing tasks. The performance analysis of the completed system is also presented computational complexity while offering improved flexibility. The performance time is also presented, where the whole process is run with a noticeable 3 seconds delay in getting the final output

    Bio-Rational Management of Maize Weevil, Sitophilus Zeamais in Maize (Zea Mays) Seeds

    Get PDF
    Bangladesh is a sub-tropical and humid country. That is why, the infestation of insects during storage is very common here. The maize weevil, Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae), locally known as “Katta Poka”, is one of the most serious cosmopolitan pest of stored cereal grain, especially of maize (Zea mays L.), in tropical and subtropical regions including Bangladesh. Considering the issue, the study was conducted in the laboratory of Department of Entomology, Bangladesh Agricultural University (BAU) following completely randomized design (CRD) with three replications to evaluate the efficacy of four locally available botanicals and chemicals. The botanicals used were: Neem (Azadirachta indica) leaf, Datura (Datura stramonium) leaf, Nishinda (Vitex negundo L) leaf and Garlic (Allium sativum L.) tablet powders at three different doses (3, 4 and 5gm)/100g of grain seed against maize weevil. The results revealed that all test materials at 5g doses exhibited higher mortality action against maize weevil while at 3g doses it gave the lowest percentage efficacy. Powdered leaves of neem and datura at 4 and 5gm were showed statistical significant (P<0.01) differences while powdered leaves of nishinda at the similar rates were observed with moderately effectiveness and powdered tablet of garlic gave the lowest mortality rate within 28 days of exposure in all tested doses. These findings suggest that botanical treatments exerted better mortality of maize weevil and reduced maize seed weight loss with higher germination capacity compared to the untreated control. It was also observed that the highest mortality percentage, lowest seed weight loss and highest germination capacity in the seeds which were treated with Sevin 85SP at the rate of 0.25g/100g maize seeds. Maize grains treated with botanicals, indicated that insect reproduction and development were impaired in all botanical pesticides. It is suggested that datura leaf, neem leaf powder can be used as good alternatives to chemical insecticides against S. zeamays due to their higher mortality, lower seed weight losses and higher germination capacity

    Genotyping and phylogenic study of Acanthamoeba isolates from human keratitis and swimming pool water samples in Iran

    Get PDF
    Objective: Acanthamoeba keratitis cause severe corneal infection and lead to poor vision and blindness. This disease is caused by a unicellular amphizoic protozoon called Acanthamoeba spp. that present in different environments. This study aimed to represent the existence and genotyping of Acanthamoeba spp. in patients with keratitis and swimming pool water (SPW) in Tehran Province, Central Iran. Methods: In this descriptive study, 56 clinical samples were collected from patients with keratitis and 30 water samples were collected from different swimming pools in Tehran Province. All samples were examined based on the morphological and molecular techniques. The genotypes were determined by sequencing the partial of 18S rRNA gene. Results: Of 56 clinical (corneal) and 30 environmental (SPW) samples, 30.3 and 40.0 were positive for Acanthamoeba spp., respectively. According to sequencing analysis, 94.1 of amoebic keratitis isolates were belonged to T4 genotype and only one (5.8) isolate was belonged to T11 genotype. All genotypes were detected from SPW samples were identified as T4 genotype. Conclusion: According to our results, use of contact lens and swimming in pool poses the major risk factor for amoebic keratitis in the studied area (Tehran). Moreover, T4 genotype was the predominant genotype of human keratitis and swimming pool samples there. Consequently, essential and practical measures are urgently needed to prevent subjects against this ocular seriously disease. © 202

    Presence and diversity of Leishmania RNA virus in an old zoonotic cutaneous leishmaniasis focus, northeastern Iran: haplotype and phylogenetic based approach

    Get PDF
    Objective: Leishmania RNA virus (LRV) is a double-stranded RNA (dsRNA) virus that circulates within many species of the Leishmania parasite. In this study, we aimed to investigate the presence of LRV2 circulating in Leishmania isolates in an old focus of ZCL located in northeastern of Iran. Methods: Leishmania isolates were collected from 85 patients that confirmed to have cutaneous leishmaniasis (CL) based on parasitological examination. To identify the Leishmania isolates, species-specific primer sets were applied for molecular identification. The presence of LRV2 was performed by RdRp-semi nested-PCR. The genetic diversity were calculated using MEGA and DnaSP. To assess haplotype diversity, 31 LRV2 strains in different regions were surveyed using analysis a 292-bp section of the RdRp sequences. Results: Out of 85 patients, 83 (97.6 ) were diagnosed with L. major and 2 (2.4 ) with L. tropica. LRV2 virus was detected in 59 (69.4) of the CL cases. For the first time, LRV2 was reported in one L. tropica strain in Iran. The current LRV2 sequences indicated the highest similarities to an Old World LRV2. Moreover, 10 unique haplotypes were identified based on the analyzed sequences of the RdRp gene. Conclusions: Our results indicated the highest occurrence of Leishmania/LRV2 co-circulation in this known ZCL focus from northeastern Iran. Phylogenetic analyses of LRV2 sequences confirmed that these isolates belong to the order of LRV2 from the Old World. This study offered an insight into LRV2 haplotype that the informative issue can be used for genetic research of LRV2 in other regions. © 2020 The Author(s

    Cloud computing: survey on energy efficiency

    Get PDF
    International audienceCloud computing is today’s most emphasized Information and Communications Technology (ICT) paradigm that is directly or indirectly used by almost every online user. However, such great significance comes with the support of a great infrastructure that includes large data centers comprising thousands of server units and other supporting equipment. Their share in power consumption generates between 1.1% and 1.5% of the total electricity use worldwide and is projected to rise even more. Such alarming numbers demand rethinking the energy efficiency of such infrastructures. However, before making any changes to infrastructure, an analysis of the current status is required. In this article, we perform a comprehensive analysis of an infrastructure supporting the cloud computing paradigm with regards to energy efficiency. First, we define a systematic approach for analyzing the energy efficiency of most important data center domains, including server and network equipment, as well as cloud management systems and appliances consisting of a software utilized by end users. Second, we utilize this approach for analyzing available scientific and industrial literature on state-of-the-art practices in data centers and their equipment. Finally, we extract existing challenges and highlight future research directions
    corecore