1,077 research outputs found

    Speeded Up Robust Features Descriptor for Iris Recognition Systems

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    اكتسبت النظم البايومترية اهتماما كبيرا لعدة تطبيقات. كان تحديد القزحية أحد أكثر التقنيات البايومترية تطوراً للمصادقة الفعالة. نظام التعرف على القزحية الحالية يقدم نتائج دقيقة وموثوق بها على أساس الصور المأخوذة بالأشعة التحت الحمراء (NIR) عندما يتم التقاط الصور في مسافة ثابتة مع تعاون المستخدم. ولكن بالنسبة لصور العين الملونة التي تم الحصول عليها تحت الطول الموجي المرئي (VW) دون التعاون بين المستخدمين، فإن كفاءة التعرف على القزحية تتأثر بسبب الضوضاء مثل صور عدم وضوح العين، و تداخل الرموش ، والانسداد  بالأجفان وغيرها. يهدف هذا العمل إلى استخدام (SURF) لاسترداد خصائص القزحية في كل من صور قزحية NIR والطيف المرئي. يتم استخدام هذا النهج وتقييمه على قواعد بيانات CASIA v1and IITD v1 كصورة قزحية NIR وUBIRIS v1 كصورة ملونة. وأظهرت النتائج معدل دقة عالية (98.1 ٪) على CASIA v1, (98.2) على IITD v1 و (83٪) على UBIRIS v1 تقييمها بالمقارنة مع الأساليب الأخرى.Biometric systems have gained significant attention for several applications. Iris identification was one of the most sophisticated biometrical techniques for effective and confident authentication. Current iris identification system offers accurate and reliable results based on near- infra -red light (NIR) images when images are taken in a restricted area with fixed-distance user cooperation. However, for the color eye images obtained under visible wavelength (VW) without cooperation between the users, the efficiency of iris recognition degrades because of noise such as eye blurring images, eye lashing, occlusion and reflection. This works aims to use Speeded up robust features Descriptor (SURF) to retrieve the iris's characteristics in both NIR iris images and visible spectrum. This approach is used and evaluated on the CASIA v1and IITD v1 databases as NIR iris image and UBIRIS v1 as color image. The evaluation results showed a high accuracy rate 98.1 % on CASIA v1, 98.2 on IITD v1 and 83% on UBIRIS v1 evaluated by comparing to the other method

    Les mouvements de population provoqués par la sécheresse

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    Le flux et le reflux de paysans et de travailleurs pauvres migrant sous la pression de conditions de vie désastreuses et dans l'espoir d'une vie meilleure, leur départ-dispersion et leur réinstallation-regroupement, constituent au Soudan un ensemble de phénomènes collectifs de première importance qui reflète l'ampleur des crises de tous ordres qu'a connues le pays ces dernières années (Mohammed, 1989). On distingue habituellement deux sortes de mouvements de population : ceux qui sont volonta..

    Effect of Sildenafil Citrate on Success Rate of Ovulation Induction by Clomiphene Citrate

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    Background: Disorders of ovulation are common causes of infertility, and polycystic ovary syndrome (PCOS) is by far the most frequent condition. Objetive: The aim of this work was to evaluate the effect of adding vaginal sildenafil citrate to clomophine citrate used as ovarian stimulant drug on both endometrial thickness and pregnancy rate in patient with polycystic ovary syndrome (PCO). Patients and Methods: This prospective Comparative study included a total of 58 patients with primary and secondary infertility aged between18 years to 35 years, attending at Outpatient Clinics, Obstetrics and Gynecology Department, Zagazig University Hospitals. Patients were divided into two equal groups; each were 29. 1st Group was given clomiphene, and 2nd group was given Clomophine citrate and Sildenafil. A transvaginal Scan for imaging the uterus and adnexa for any pathology and measuring the basic endometrial thickness was also done on Day 3. Results: This study shows that there was an increase in endometrial thickness in sildenafil group (13.4±1.814 mm) comparable with clomiphene citrate group only (8.52±2.081 mm) (P=0.01). The result was statistically significant with increase threshold regard for implantation with statistically significant in group B (P=0.018). Conclusions: It could be concluded that addition of sildenafil citrate to clomiphene citrate therapy for induction of ovulation in patients with PCOS resulted in significant increase of endometrial thickness and non-significant increase of pregnancy Rates

    Two-level scheduling scheme for integrated 4G-WLAN network

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    In this paper, a novel scheduling scheme for the Fourth Generation (4G)-Wireless Local Area Network (WLAN) network is proposed to ensure that end to end traffic transaction is provisioned seamlessly. The scheduling scheme is divided into two stages; in stage one, traffic is separated into Actual Time Traffic (ATT) and Non-Actual-Time Traffic (NATT), while in stage two, complex queuing strategy is performed. In stage one, Class-Based Queuing (CBQ) and Deficit Round Robin (DRR) are used for NATT and ATT applications, respectively to separate and forward traffic themselves according to source requirements. Whereas in the stage, two Control Priority Queuing (CPQ) is used to assign each class the appropriate priority level. Evaluation of the performance of the integrated network was done according to several metrics such as end-to-end delay, jitter, packet loss, and network’s throughput. Results demonstrate major improvements for AT services with minor degradation on NAT applications after implementing the new scheduling scheme

    Holograms in Optical Wireless Communications

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    Adaptive beam steering in optical wireless communication (OWC) system has been shown to offer performance enhancements over traditional OWC systems. However, an increase in the computational cost is incurred. In this chapter, we introduce a fast hologram selection technique to speed up the adaptation process. We propose a fast delay, angle and power adaptive holograms (FDAPA-Holograms) approach based on a divide and conquer methodology and evaluate it with angle diversity receivers in a mobile optical wireless (OW) system. The fast and efficient fully adaptive FDAPA-Holograms system can improve the receiver signal to noise ratio (SNR) and reduce the required time to estimate the position of the receiver. The adaptation techniques (angle, power and delay) offer a degree of freedom in the system design. The proposed system FDAPA-Holograms is able to achieve high data rate of 5 Gb/s with full mobility. Simulation results show that the proposed 5 Gb/s FDAPA-Holograms achieves around 13 dB SNR under mobility and under eye safety regulations. Furthermore, a fast divide and conquer search algorithm is introduced to find the optimum hologram as well as to reduce the computation time. The proposed system (FDAPA-Holograms) reduces the computation time required to find the best hologram location from 64 ms using conventional adaptive system to around 14 ms

    Utilization of waste as a constituent ingredient for enhancing thermal performance of bricks – a review paper

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    In view of the environmental regulations, practitioners have been inclined to use bricks with higher insulation capability, however with minimal attention to sustainable material composition, let alone waste material. From a research perspective, in the wake of the growing concerns for the environment, the use of waste material to develop bricks which can exhibit suitable characteristics attributed to the material composition has been on the rise. However, the extant literature on utilization of waste materials for brick mix design has neglected to provide detailed literature review on the influence of waste materials on the thermal performance of bricks. Methods: This paper provides detailed review of research conducted on thermal properties of bricks produced from various types of waste. Influence of the method of manufacturing and type of waste on thermal performance of bricks is discussed. A sustainability selection criteria format is provided to assist optimal decision making in considering alternative sustainable waste material. Findings: A sustainability selection criteria format is provided to assist optimal decision making in considering alternative sustainable waste material. Applications: The outcome of this paper can serve as a common reference for practitioners and researchers attempting to seek out solutions for further improving overall quality of thermally insulated waste-incorporated bricks, paving the way for more focused research on waste utilization in the development of more sustainable wall material based on the current brick production process

    Benign Pulmonary Metastasizing Leiomyoma: A Case Report

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    Introduction: Benign metastasizing leiomyoma (BML) is a rare disease, the first case of BML was reported by Steiner in 1939. It can affect any age group ranging from 30 to 75 years, but most commonly found in late childbearing period. Leiomyoma of the uterus can metastasize to different organs but lung is the most common site, hence the term pulmonary benign metastasizing leiomyoma (PBML) is used. PBML is mostly diagnosed incidentally on imaging studies for other conditions. It can occur many years after hysterectomy for Leiomyoma of uterus.Presentation of the cases: We report a case of a 51 years old lady with chronic cough and pulmonary nodules on a computerized  tomography (CT) scan. She was referred to our hospital for the management of the probable metastatic cancer. Her diagnosis was challenging but a past history of hysterectomy, radiological findings and the histopathology helped us to diagnose this rare condition of benign metastasizing leiomyoma (BML).Conclusion: Pulmonary benign metastasizing leiomyoma is rare benign disease. It should be considered as the probable diagnosis in a female patient with pulmonary nodules and a previous history of surgery for leiomyoma of uterus.  Pathological differentiation from leiomyosarcoma and other malignant metastatic condition is essential. Prognosis of PBML after surgical and/ or hormonal treatment is good

    Collaborative VLC/IROW Systems

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    Dimming is an important feature of an indoor lighting system where the illumination level can be controlled by the user. Therefore, integrating a visible light communication (VLC) system with an illumination system poses some challenges. One of the main issues is that the light unit should be “ON” all the time to ensure continuous communication. To ensure acceptance and adoption of VLC systems, an important issue should be addressed: how to communicate when the lights are “OFF” or partially dimmed. In this chapter, we propose five new infrared optical wireless (IROW) systems to support VLC systems when the light is totally turned off or significantly dimmed. To take advantage of both VLC and IROW, we introduce and implement the concept of a collaborative VLC/IROW system. In addition, we investigate the impact of partial dimming on the VLC system’s performance, and we propose an adaptive rate technique (ART) to mitigate the impact of light dimming. Moreover, in the case of no dimming, the VLC and IROW systems can collaborate to increase the data rate so it is higher than that in the pure VLC system. We have achieved 10 Gbps in an indoor environment, which is a 2× increase in the data rate compared with a pure VLC system
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