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گرايش به سو ي ايجاد موسس ه ه اي سرو يس گرا مستلزم توصيفي رسم ي از معمار ي كسب و كار است تا بد ين تر تي ب اند ي شه سرويس گرايي كسب و كار را منعكس سازد . براي معرفي سرو يس جديد در ي ك كس ب و كار از ديدگاه IT تكنيك هاي SOA اين امكان را م يدهند تا مدل ي از جنبه ه اي كاربرد ي سرو يس ايجاد شود ، اما از ديدگاه كسب وكار، چن دين جنبه از ا ين سرو يس جد يد وجود دارد كه در چارچوب معمار ي كسب و كار مدلساز ي نشد ه اند. يكي از انگ ي زهها برا ي ايجاد مدلساز ي كسب و كارِ سرو يس گرا _ كه چند ين حوزه كسب و كار را به ز ير پوشش خود م ي برد_ اين است كه از آن به عنوان چارچوبي بر اي تسهيل استنتاج كسب وكار سر ويس گرا استفاده شود . بيشتر ساختارها ي كسب و كار از IT شروع به كار مي كنند و توانمند ي هاي IT را بصورت سرويس در م يآورن د. در مدلساز ي پي شنهادي اي ن مقاله، سر و يس كسب وكار با همه حوزههاي كليدي معمار ي كس ب و كار در ارتباط است و هم به مدلساز ي جنب ه هاي كس ب و كار و هم به جنبه ه اي عم لي اتي سرويس هاي كس بوكار توجه بسياري مي شود.

در اين مقاله، مرز فعال خودنسبي معرفي و پايداري آن در برابر نويز مطالعه و بررسي شده است. بررسي ها نشان داد كه هر دو نسخه استاتيك و ديناميك الگوريتم پيشنهادي در برابر نويز تصوير بسيار مقاوم بوده و در اين زمينه ، برتري محسوسي نسبت ب ه ساير مرزهاي فعال دارد. نتايج تجربي نيز بيانگر عملكرد قابل توجه مرز فعال خودنسبي در ناحيه بندي مجموعه اي از تصاوير مصنوعي و پزشكي در مقايسه با چند مرز فعال ديگر مي باشد. ويژگي هايي چون دامنه جذب وسيع، بازسازي گسستگي هاي مرز، استخراج مرزهاي ضعيف و مقاومت در برابر نويز الگوريتم پيشنهادي را به روشي مناسب براي ناحي ه بندي تصاوير پزشكي بدل نموده است.

در اين مقاله، روشي جهت استخراج ويژگيهاي پايدار از تصاوير عنبيه بر اساس تبديل ويژگي غير وابسته به مقياس جهت شناسايي هويت ارائه شده است. مزيت اين روش بر روشهاي رايج عدم حساسيت به تغييرات مقياس، حركت و چرخش در تصاوير ميباشد. همچنين نويسندگان، پايگاه داده جديد IRIRIS متشكل از تصاوير عنبيه اخذ شده در زوايا و فواصل متفاوت در شرايط نور محيطي را ايجاد نموده و روش ارائه شده را بر روي تصاوير اين پايگاه داده جهت يافتن اين ويژگيها اعمال و به نتيجه تطبيق بالايي بر اساس اين ويژگيها دست يافتند. در نهايت پارامترهاي مهم تاثير گذار بر الگوريتم استخراج نقاط كليدي مورد بررسي قرار گرفته است.

On-Demand Multicast Routing Protocol (ODMRP) is a well-known protocol for ad hoc networks. This protocol is mesh based and exhibits a high packet delivery ratio even at high mobility. In ODMRP the robustness is achieved by using the number of multiple routes which is a solution for the high speed mobility and the subsequent route breaking. The ODMRP is such designed that the number of multiple routes only depends on the number of senders and receivers, irrespective of the node speed and the traffic load. In this paper we proposed a Reduced Data Transmission ODMRP (RDTODMRP) routing algorithm that considers the network conditions e.g. mobility speed and traffic load to determine the multiple routs. This cuts down the unnecessary redundant routes and their data transmissions. Furthermore in ODMRP and RDTODMRP, flooding of Join-Request packets causes excessive control overhead, In order to solve the problem, we Limit some nodes to Flood Join-Request packets and forbid it to be a forwarding node (LF-RDTODMRP). It is shown by simulation that the RDTODMRP and LF-RDTODMRP reduce the number of data transmission, control overhead, end to end delay and improve the data packet delivery ratio.

Grid computing is a promising technology for future computing platforms and is expected to provide easier access to remote computational resources that are usually locally limited. Scheduling is one of the active research topics in grid environments. The goal of grid task scheduling is to achieve high system throughput and to allocate various computing resources to applications. The Complexity of scheduling problem increases with the size of the grid and becomes highly difficult to solve effectively. Many different methods have been proposed to solve this problem. Some of these methods are based on heuristic techniques that provide an optimal or near optimal solution for large grids. In this paper we introduce a new task scheduling algorithm based on Ant Colony Optimization (ACO). According to the experimental results, the proposed algorithm confidently demonstrates its competitiveness with previously proposed algorithms.

Binary Arithmetic Coding (BAC) is among the techniques used in H.264 video coding standard to improve the coding efficiency. BAC includes an iterative process of renormalization with up to seven iterations for coding each symbol. Since BAC is also a computational intensive unit in H.264 encoder, various hardware realizations have been proposed for it in the literature. In this paper, we propose a hardware implementation for BAC, which uses lookup table to avoid the iterative coding process and achieves coding rate of one symbol per clock at 260 MHz clock rate. Post synthesize simulation results indicate that the proposed architecture is a resource and speed efficient hardware for H.264 binary arithmetic encoder.

In this work, we present SIMUIINK bit-true modeling of the conjugate structure-algebraic CELP (CS-ACELP) speech coder which has been chosen as the core layer of speech coder standard ITU-T G.729.1. The optimum bit numbers of the computational blocks are defined as the minimum word-widths that maintain the quality of the output with minimum chip area and power. Such optimum bitwidth of the coefficients and the internal computations are extracted. As a result, a golden model of the codec which best suits as a reference for its hardware implementation is developed. The power and area improvements are estimated in two blocks of CSACELP speech coder.

Background modeling is one of the most important parts of visual surveillance systems. Most background models are pixel-based which extract detailed shape of moving objects, but they are so sensitive to nonstationary scenes. In many applications there is no need to detect the detailed shape of moving objects. So some researchers use block-based methods instead of pixel-based which are more insensitive to local movements. These two methods are complementary to each other. We propose an efficient hierarchical method by which the block level information is utilized intelligently to improve the efficiency and robustness of pixel level. Experimental results demonstrate the effectiveness of the algorithm when applied in different outdoor and indoor environments.

In recent years, processing the images that contain human faces has been a growing research interest because of establishment and development of automatic methods especially in security applications, compression, and perceptual user interface. In this paper, a new method has been proposed for multiple face detection and tracking in video frames. The proposed method uses skin color, edge and shape information, face detection, and dynamic movement analysis of faces for more accurate real-time multiple face detection and tracking purposes. One of the main advantages of the proposed method is its robustness against usual challenges in face tracking such as scaling, rotation, scene changes, fast movements, and partial occlusions.

Vehicle tracking is an essential requirement of any vision based Intelligent Transportation System for extracting different traffic parameters, efficiently. Handling inter-object occlusion is the most challenging part of tracking as a process of finding and following interested objects in a sequence of video frames. In this paper we present a system, based on code-book background model for motion segmentation and Kalman filter for tracking with a new approach for occlusion. This approach separates occluded vehicles based on longest common substring of chain codes. We use this tracking system to estimate some traffic parameters. Experimental results show the efficiency of the method

The existing workflow modeling languages have some limitations and drawbacks. The aim is to introduce a new workflow modeling language based on stochastic activity networks (SANs). SANs are a powerful extension of Petri nets, which have been used in a wide range of applications. SAN-based workflow modeling language (SWML) has some high-level modeling primitives for easily modeling workflow patterns. For analysis of the modeled workflow systems with SWML, we have introduced the transformation techniques from SWML models into ordinary SANs. The transformed models can be analyzed using the existing tools for SANs, such as the Möbius modeling tool. In this paper, we present definitions of SWML modeling language and its primitives and an example of SWML models.