2,583 research outputs found

    Using association rule mining to enrich semantic concepts for video retrieval

    Get PDF
    In order to achieve true content-based information retrieval on video we should analyse and index video with high-level semantic concepts in addition to using user-generated tags and structured metadata like title, date, etc. However the range of such high-level semantic concepts, detected either manually or automatically, usually limited compared to the richness of information content in video and the potential vocabulary of available concepts for indexing. Even though there is work to improve the performance of individual concept classifiers, we should strive to make the best use of whatever partial sets of semantic concept occurrences are available to us. We describe in this paper our method for using association rule mining to automatically enrich the representation of video content through a set of semantic concepts based on concept co-occurrence patterns. We describe our experiments on the TRECVid 2005 video corpus annotated with the 449 concepts of the LSCOM ontology. The evaluation of our results shows the usefulness of our approach

    Cold atom confinement in an all-optical dark ring trap

    Full text link
    We demonstrate confinement of 85^{85}Rb atoms in a dark, toroidal optical trap. We use a spatial light modulator to convert a single blue-detuned Gaussian laser beam to a superposition of Laguerre-Gaussian modes that forms a ring-shaped intensity null bounded harmonically in all directions. We measure a 1/e spin-relaxation lifetime of ~1.5 seconds for a trap detuning of 4.0 nm. For smaller detunings, a time-dependent relaxation rate is observed. We use these relaxation rate measurements and imaging diagnostics to optimize trap alignment in a programmable manner with the modulator. The results are compared with numerical simulations.Comment: 5 pages, 4 figure

    Evaluation of therapeutic response of Keloid and Hypertrophic scars to bleomycin tatto and to cryotherapy followed by intralesional triamcinolone injection

    Get PDF
    کلوئید و اسکارهایپرتروفیک بیماری هایی هستند ناشی از پاسخ غیر طبیعی پوست بدن به صدمات وارده که به علت تولید بیش ازحد بافت های فیبروس متراکم در محل ضایعه ایجاد می شوند. از بین درمان های بسیار زیاد پیشنهاد شده برای این بیماری ها، کرایوتراپی و تزریق داخل ضایعه تریامسینولون جزء متداول ترین این درمان ها است، اما هنوز موفقیت درمانی در این بیماری کامل نیست. هدف از انجام این پژوهش بررسی پاسخ درمانی کلوئید و اسکارهایپرتروفیک به تاتوی بلئومایسین و مقایسه آن با درمان معمول کرایوتراپی و تزریق داخل ضایعه تریامسینولون می باشد. بدین منظور 45 نفر از بیماران مبتلا به کلوئید و اسکارهایپرتروفیک مراجعه کننده به درمانگاه های پوست دانشگاه علوم پزشکی اصفهان بر اساس ترتیب مراجعه به دوگروه A (23 نفر) و گروه B (22 نفر) تقسیم شدند. گروه A بوسیله تاتوی بلئومایسین و گروه B بوسیله کرایوتراپی و تزریق داخل ضایعه تریامسینولون درمان شدند. درمان ها در چهار مرحله و با فواصل یک ماهه در هر دو گروه انجام شد و بیماران تا 3 ماه پس از پایان درمان پیگیری شدند. قبل و پس از درمان اندازه (شامل ضخامت و وسعت ضایعات)، علائم کلینیکی، محل و تعداد ضایعات و دیگر اطلاعات مورد نیاز ثبت و در هر گروه مقایسه گردید. پاسخ درمانی که بر اساس کاهش اندازه ضایعات نسبت به ویزیت اول تعریف شده بود، در گروه A، 14±3/88 درصد و در گروه B، 5/22±3/67 درصد به دست آمد که تفاوت معنی داری بین دوگروه مشاهده می شود (001/0P=) ضمن آنکه 69 بیماران گروه A در مقایسه با قبل از درمان بدون علامت شده بودند در حالی که تعداد کسانی که در گروه B بدون علامت شده بودند 49 درصد بود. همچنین در گروه B هر چه اندازه ضایعه بزرگتر بود پاسخ درمانی ضعیف تری به دست می آمد ولی در گروه A اندازه ضایعات تقریباً اثری در پاسخ درمانی ایجاد نکرد. نتیجه آنکه تاتوی بلئومایسین پاسخ درمانی بالائی می تواند در این بیماری ها ایجاد کند خصوصاً آنکه در ضایعات با اندازه بزرگ نیز اثر درمانی آن حفظ می شود

    Development of optimal accelerated test plan

    Get PDF
    This paper describes an optimal accelerated test plan considering an economic approach. We introduce a general framework to obtain plans of optimal accelerate tests with a specific objective, such as cost. The optimal test plans are defined by considering prior knowledge of reliability, including the reliability function and its scale and shape parameters, and the appropriate model to characterize the accelerated life. This information is used in Bayesian inference to optimize the test plan. The prior knowledge contains the uncertainty on real reliability of new product. So, the proposed methodology consists of defining an optimal accelerated testing plan while considering an objective function based on economic value, using Bayesian inference for optimizing the test plan, and using the uncertainty of the parameters to obtain a robust, optimal testing plan. The objective function consists of two terms: the cost linked to testing activities and the cost associated with operation of the product. Finally, we will develop our optimal plan by extending our approach to include theoretical formulation of the various degrees of freedom with respect to the parameters. To complete this development, we need to improve the algorithm of optimization. To obtain the best test plan, we propose an optimization procedure using the genetic algorithm. The proposed method will be illustrated by a numerical example based on a well-known problem

    Optimal accelerated test plan: optimization procedure using Genetic Algorithm

    Get PDF
    This paper describes an optimization procedure using Genetic Algorithm to define an optimal accelerated test plan considering an economic approach. We introduce a general framework to obtain plans of optimal accelerate tests with a specific objective, such as cost. The objective is to minimize the costs involved in testing without reducing the quality of the data obtained. The optimal test plans are defined by considering prior knowledge of reliability, including the reliability function and its scale and shape parameters, and the appropriate model to characterize the accelerated life. This information is used in Bayesian inference to optimize the test plan. To perform optimization, a specific genetic algorithm is decribed and applied to obtain the best test plan. This procedure is then illustrated on a numerical example

    Cylindrical vector beams for rapid polarization-dependent measurements in atomic systems

    Full text link
    We demonstrate the use of cylindrical vector beams - beams with spatially varying polarization - for detecting and preparing the spin of a warm rubidium vapor in a spatially dependent manner. We show that a modified probe vector beam can serve as an atomic spin analyzer for an optically pumped medium, which spatially modulates absorption of the beam. We also demonstrate space-variant atomic spin by optical pumping with the vector beams. The beams are thus beneficial for making singleshot polarization-dependent measurements, as well as for providing a means of preparing samples with position-dependent spin.Comment: 8 pages, 5 figures. Accepted in Optics Expres

    A low-loss photonic silica nanofiber for higher-order modes

    Full text link
    Optical nanofibers confine light to subwavelength scales, and are of interest for the design, integration, and interconnection of nanophotonic devices. Here we demonstrate high transmission (> 97%) of the first family of excited modes through a 350 nm radius fiber, by appropriate choice of the fiber and precise control of the taper geometry. We can design the nanofibers so that these modes propagate with most of their energy outside the waist region. We also present an optical setup for selectively launching these modes with less than 1% fundamental mode contamination. Our experimental results are in good agreement with simulations of the propagation. Multimode optical nanofibers expand the photonic toolbox, and may aid in the realization of a fully integrated nanoscale device for communication science, laser science or other sensing applications.Comment: 12 pages, 5 figures, movies available onlin

    Opium addiction in patients with coronary artery disease: A grounded theory study

    Get PDF
    Background: There are widespread misconceptions about the positive effects of opium on coronary artery disease (CAD). Thus, we performed a study to explore the opium addiction process contributing factors among CAD patients using a grounded theory approach. Methods: The sample comprised 30 addicted CAD patients and their family members, physicians, nurses and friends. Purposive and theoretical sampling was employed; semi-structured interviews were conducted. Coding and constant comparative analysis techniques were as proposed by Strauss and Corbin (1998). Results: The core category was 'Fighting for Survival', comprising three main themes, namely, 'the gateway', 'blowing into the fire' and 'getting stuck in the mud'. Conclusion: Increasing knowledge about the adverse effects of opium on the cardiovascular system would reinforce prevention and rehabilitation measures. Involving patients' family-members in addiction prevention and rehabilitation programs and referring patients to specialized rehabilitation centres could help patients quit opium. Healthcare providers (HCPs) should notice to the effects of opium consumption among CAD patients; nursing care must be holistic in nature. Although opium is stigmatised in Iran, HCPs must treat addicted CAD patients similar to other patients. Nursing students' must be aware of the negative effects of illegal drugs on CAD patients and the misconceptions regarding the positive effects thereof. Any misconceptions must be probed and clarified. Rehabilitation centres must be supervised by cardiologists and HCPs
    corecore