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In this paper, the solution of constrained nonlinear programming problems by a Sequential Quadratic Programming (SQP) is considered. The aim of the present work is to promote global convergence without the need to use a penalty and Barrier functions in the mixed interior-exterior point method. Instead, a new concept of a “filter” that aims to minimize the objective function and its approach that allows appoint to be accepted if reduces the objective function and satisfies the constraint violation function. If that point is rejected a new point is tested.

This paper investigates a novel algorithm for compressing and encrypting Arabic short text messages (SMS messages). Short text messages are used in cellular networks. Compression is required for saving the transmission energy or to use bandwidth in an efficient manner in addition to save the user money while the end-to-end effective encryption is required for security providence. This work succeeded to overcome small size limitation of the SMS message by changing Arabic characters coding from Unicode to Base64 coding scheme and developing a runt version of lossless Huffman coding scheme. Examples are shown where the application of the text compressor for short message services offering more than three times the capacity compared to a standard message.

There are two basic types of symmetric algorithms: block ciphers and stream ciphers. Block ciphers operate on blocks of plaintext and ciphertext—usually of 64 bits but sometimes longer. Stream ciphers operate on streams of plaintext and ciphertext one bit or byte (sometimes even one 32-bit word) at a time. With a block cipher, the same plaintext block will always encrypt to the same ciphertext block, using the same key. With a stream cipher, the same plaintext bit or byte will encrypt to a different bit or byte every time it is encrypted. In this paper we introduce three developments of Counter Mode of Operation of Block cipher. These developments merge between advantages of Counter Mode with other Modes. This gives a good secure Modes for General purpose block-oriented transmission Authentication, Random access, Stream-oriented transmission over noisy channel.

One of the key issues of modern cryptography is the problem of establishing a secure end-to-end communication over an insecure communication channel. Short Message Service (SMS) is a hugely popular and easily adopted communications technology for mobile devices. Users conduct business, disclose passwords and receive sensitive notification reports from systems using this communication technology. SMSs by default are sent in clear text form within the serving GSM (Global System for Mobile communications) network, Over The Air (OTA), and potentially over the public Internet in a predictable format. This allows anyone accessing the GSM system to read, and or modify the SMS content even on the fly. In this paper, we present an approach mainly consists of two steps, first, SHA-1 authentication is used to generate a message digest that is combined with previous message digest and a shared secret key to form an initial key stream. Secondly, this key will be used as input to a mathematical equation derived in prefix notation from randomly selected set of operators and functions supported by the software platform extracted from special table. The final key stream is the output of this equation which is a one time pad to encrypt the original message text. Lastly, encrypted SMS message will be sent and a randomized operation will be then applied to that table. A one-time pad, considered to be the only perfectly secure cryptosystem, secures an SMS message for transport over any medium between a mobile device and the serving GSM network and through it too.

Image matching plays an important role in many applications such as multi-modality medical imaging and multi-spectral image analysis. The role of matching is to integrate multiple sources of object information into a single image. The matching problem consists of determining the unknown transform parameters required to map one image to match the other image(20). Different non – traditional methods are used for solving this kind of problem. Among these methods are the Genetic Algorithms, Neural Networks & Simulating Annealing. Swarm Intelligence (SI) algorithms take their inspiration from the collective behavior of natural, for example, ant colonies, flocks of birds, or fish shoals, a particularly successful strandant colony optimization (ACO)(1). Ant Colony Optimization is a population-based general search technique, proposed by Dorigo(1992,1996), for the solution of difficult combinatorial problems)4). The studies show that, in nature, the ant colony is able to discover the shortest paths between the nest and food sources very efficiently, such a deposit substance is called pheromone during talking and another ants can smell it, if one of ants find a short path, it feedback on the same path and the value of pheromone on this path increases and a another ants gradually chose this path.(22) Tabu search is one of the best known heuristic to choose the next neighbor to move on. At each step, one chooses the best neighbor with respect to specific function (23). The basic idea in this paper is using Ant Colony Optimization(ACO) & Tabu Search(TS) as a success strategy for matching two images. The suggestion algorithm evaluation is a good promising solution, by providing an optimal algorithm which is executed by optimal time and coast, I believe that there is no prior research conjoining the two topics in this way. The program is written in Matlab language (6.5).

The aim of the project is to develop parallel approaches for both the simplex that are used in linear programming to solve linear module systems. Most of these models are time consuming when executed and processed in the sequential microprocessor computers. During the project, we try to decrease this time and increase the efficiency of the algorithm for the two methods simplex, through developing parallel methods appropriate to be executed on MIMD type computers. In this paper, three algorithms were suggested for paralleling (a developed algorithm and a comparison was made between the three algorithms and the original. This comparison is included in second section. In general, the practical results and the suggested programs for these new algorithms proved to be better in performance than their analogues that are executed in computers of sequential processor in view of the two elements of execution time and algorithm time.

In this paper, a new hybrid conjugate gradient algorithm is proposed for unconstrained optimization. This algorithm combines the desirable computation aspects of Polak-Ribière steps and useful theoretical features of Fletcher-Reeves CG-steps. Computational results for this algorithm are given and compared with those of the Fletcher and Polak standard CG methods showing a considerable improvement over the latter two methods.

After having reviewed the RETARD code, which was originally written by Hairer & Wanner in 1995 with the aim of solving delay differential equations (DDEs), a new arithmetic called OSFESOR code is presented in this paper. The OSFESOR (Optimal stepsize for each step of RETARD) code is a tool for automatic implementation of DDEs in Fortran 77. Consequently, by use of the OSFESOR code, it is possible during the run of a program to evaluate the solution of DDEs with optimal stepsize, H, for each step , to evaluate the accuracy of any result provided by the computer . In short, the use of OSFESOR code serves to validate the result provided by a computer, and to assure the user of the reliability of scientific computations.

The main purpose of this paper is to study ERT and MERT rings, in order to study the connection between such rings and II-regular rings.

In this paper a class of self-scaling VM-algorithms for unconstrained optimization is investigated. Some theoretical results are given on the scaling strategies that guarantee the global convergence of the new proposed algorithm.