به نام خدا
Title: Design for rebirth (DFRb) and data structure
Author: Christian Mascle
Abstract: In this paper, rebirth, the methodology of design for rebirth antedate structure which it requires will be examined. Rebirth is a global strategy of product analysis for sustainable development. A methodology is developed to conceive a product according to objectives defined by its end of life and its generic engineering requirements, and this methodology is implanted in a framework. Our data structure is based on topological information from a boundary representation (B-rep) model and it processes all information relative to the life cycle of the product. The software, based on this data structure, allows predefining certain characteristics based on knowledge of the company or on the data base. This facilitates its use for a wide range of applications.
Publish Year: 2013
Published in: International Journal of Production Economics - Science Direct
Number of Pages: 12
موضوع: پایگاه داده
ایران سای – مرجع علمی مقالات علمی فنی مهندسی
حامی دانش بومی ایرانیان
به نام خدا
Title: Security Issues in Vehicular Networks
Authors: Yeongkwun Kim Injoo Kim
Abstract: Vehicular ad-hoc networks (VANETs) have become the focus of much discussion due to its potential role in helping to improve traffic management and safety and enable a wide range of value-added services such as collision warning/avoidance and work zone warning. Because information transmitted over a vehicular network is sensitive and can affect important safety decisions, security requirements for VANETs applications prove stringent. Thus, fail-safe security is mandatory. However, providing security in vehicular networks raises important privacy concerns also worth considering. Security and privacy are the two main concerns motivating robust vehicular network designs. In this paper, we will discuss some threats and attacks that can be exploited, and in response, present some viable security solutions.
Publish Year: 2013
Published in: ICOIN - IEEE
Number of Pages: 5
موضوع: امنیت شبکه (Network Security)
ایران سای – مرجع مقالات علمی فنی مهندسی
حامی دانش بومی ایرانیان
به نام خدا
به دنبال طرحهای گذشته و در راستای برآورده ساختن درخواست تعداد زیادی از کاربران مبنی بر استفاده از تخفیفهای ویژه، با موافقت مدیریت محترم مجموعه، مقارن با ایام گرامی ماه های رجب و شعبان، طرح تخفیف مبعث تا میلاد تقدیم شما عزیزان می گردد. تعرفه های این طرح به شرح زیر بوده و در بازه زمانی مبعث حضرت رسول اکرم (صل الله علیه و آله و سلم) (17 خردادماه)تا میلاد منجی عالم بشریت حضرت مهدی (عجل الله تعالی فرجه) (3 تیرماه) معتبر و قابل استفاده می باشند:
کاربرانی که 10 امتیاز خریداری می کنند 12 امتیاز دریافت خواهند کرد.
کاربرانی که 20 امتیاز خریداری می کنند 25 امتیاز دریافت خواهند کرد.
کاربرانی که 30 امتیاز خریداری می کنند 38 امتیاز دریافت خواهند کرد.
کاربرانی که 40 امتیاز خریداری می کنند 51 امتیاز دریافت خواهند کرد.
کاربران که 50 امتیاز خریداری می کنند 65 امتیاز دریافت خواهند کرد.
لازم به ذکر است استفاده از امتیازهای ویژه این طرح محدودیت زمانی نداشته و در صورت عدم استفاده از آنها، امتیازهای مربوطه برای کاربر حفظ خواهند شد. کاربران گرامی پس از خرید امتیاز، لطفا ایمیلی را به Financial@IranSci.ir با عنوان طرح مبعث تا میلاد ارسال نمایند (یا به پشتیبانی آنلاین اطلاع دهند) تا نسبت به ارتقاء امتیازشان اقدام شود.
ایران سای - مرجع مقالات علمی فنی مهندسی
حامی دانش بومی ایرانیان
به نام خدا
Title: An efficient parallel architecture for ray-tracing
Authors: Alexandre S Nery Nadia Nedjah Felipe M G Franca
Abstract: Real time rendering of three-dimensional scenes in high photorealistic details is a hard task, such as in the ray tracing rendering algorithm. In general, the performance achieved by a sequential software-based implementation of ray tracing is far from satisfactory. However, parallel implementations of ray tracing have been enabling reasonable real time performance, as the algorithm is embarrassingly parallel. Thus, a custom parallel design in hardware is likely to achieve an even higher performance. In this paper, we propose a hardware parallel architecture capable of dealing with the main desirable features of ray tracing, such as shadows and reflection effects, imposing low area cost and a promising rendering performance. Such architecture, called Grid RT, is based on the Uniform Grid acceleration structure and is intended to deliver massive parallelism through parallel ray-triangle intersection tests as well as parallel processing of many rays. A hardware implementation of the proposed architecture is presented, together with some performance results and resources requirements. The rendering is reduced by 80% using a grid configuration of eight processing elements.
Publish Year: 2012
Published in: Analog Integrated Circuits and Signal Processing - Journal of Springer
Number of Pages: 14
موضوع: پردازش موازی
ایران سای – مرجع مقالات علمی فنی مهندسی
حامی دانش بومی ایرانیان
به نام خدا
Title: A Machine Learning-based Usability Evaluation Method for eLearning Systems
Authors: Asil Oztekin, Dursun Delen, Ali Turkyilmaz, Selim Zaim
Abstract: The research presented in this paper proposes a new machine learning-based evaluation method for assessing the usability of eLearning systems. Three machine learning methods (support vector machines, neural networks and decision trees) along with multiple linear regression are used to develop prediction models in order to discover the underlying relationship between the overall eLearning system usability and its predictor factors. A subsequent sensitivity analysis is conducted to determine the rank-order importance of the predictors. Using both sensitivity values along with the usability scores, a metric (called severity index) is devised. By applying a Pareto-like analysis, the severity index values are ranked and the most important usability characteristics are identified. The case study results show that the proposed methodology enhances the determination of eLearning system problems by identifying the most pertinent usability factors. The proposed method could provide an invaluable guidance to the usability experts as to what measures should be improved in order to maximize the system usability for a targeted group of end-users of an eLearning system.
Publish Year: 2013
Published in: Decision Support Systems - Science Direct
Number of Pages: 4
موضوع: یادگیری ماشین (Machine Learning) – آموزش الکترونیک (eLearning)
ایران سای – مرجع مقالات علمی فنی مهندسی
حامی دانش بومی ایرانیان