Catálogo de publicaciones - libros

Product recycle and parts reutilization are two of the vital ways to protect environment. In recent years, more and more industries begin to adopt recycling as their key strategy. Koh, et al. [3] developed a model with an infinite production rate and finite recovery rate without backorder. In this study, we focus on how a supplier makes recycling as her dominant policy of production and procurement. An optimal production and inventory control policy with partial backordering is developed. Numerical examples and sensitivity analysis are provided to illustrate the theory.

The study introduces a Clonal Selection Algorithm (CSA), which depends on Artificial Immune System principles, for traditional facility layout problems. The CSA aims to minimize the total material handling cost between departments in a single manufacturing period. The determination of the optimum parameters for artificial intelligence algorithms is vital. Therefore a design of experiments study is made. The proposed algorithm is coded and tested by means test problems from literature based on the predefined parameters. The optimum solutions for small sized (5-8 department) layout problems are found. For larger (12, 15, 20, and 30 department) problems 1,077%, 5,703%, 1,126% and 3,671% improvements are obtained respectively. Better solutions are attained within shorter times compared with enumeration and CRAFT solutions.

For the secure transmission of information in the mobile wireless sensor network, the information between two nodes must be encrypted. To this end, nodes must share the common key necessary for encryption. At this time, the encryption algorithm should be symmetric cryptography rather than public-key cryptography in consideration of the process performance of sensor nodes, and the number of secret keys that each node must store and manage must be minimized in view of its memory capacity. In this paper, we propose a method of reducing the number of secret keys in spite of using the symmetric encryption algorithm. In this method, each node must store and manage by assigning a unique to it, and by ensuring that only those two nodes whose the Hamming Distance between their s is ”1” share the same secret key. According to this method, each node needs to store and manage only symmetric secret keys so that two nodes participating in the mobile wireless sensor network can obtain a common key for secure transmission of information. In this paper, we also propose the protocol and algorithm for obtaining a common key between two nodes using their own secret keys and the secret keys acquired from their neighbor nodes, and evaluate the performance (including node connectivity, network resilience against node capture, memory capacity, and key pool size) of our proposing method.

TCG (Trusted Computing Group) has defined a set of standards. The main features of the standards are protection against theft of secrets held on the platform and a mechanism for the platform to prove that it is in a trusted state, called attestation. However, the attestation mechanism is vulnerable to relay attack because of the lack of linkage between the endpoint identity and attestation message. We show here how to defeat the attack by employing a new agent, called Network Interface Monitoring Agent (NIMA). In addition, we show that the NIMA-based approach can render DRM more robust and efficient, especially in case of protecting a company’s sensitive data.

In 2005, Harn et al. proposed three authenticated Diffie-Hellman key-agreement protocols, each of which is based on one cryptographic assumption. In particular, the first protocol is based on a discrete logarithm, the second on an elliptic curve and the third on RSA factoring. However, the current paper demonstrates that Harn et al.’s protocols do not provide perfect forward secrecy and key freshness which are two of the standard security attributes that key exchange protocols should have. Furthermore, we proposes improvements of the protocols such that they provide these security attributes.

Digital watermarking is a technique to insert an information-carrying digital signature into a digital media so that the signature can be extracted for variety of purposes including ownership authentication and content verification. We examine the weaknesses against common watermarking attacks of blockwise independent and content-based watermarking algorithms for image integrity verification, and implement a new and more secure invisible fragile public-key watermarking algorithm for color or grayscale images that increases the message digest size from the proposed 64 to 128 bits using the same small-size blocks and maintaining high-quality watermarked images and accurate localization of image changes. Our watermarking technique is capable to detect any changes made to the image since the time it was stamped, any changes to the pixel values and also to the dimensions of the image will be automatically detected and localized. Our scheme consists of a watermark-insertion process that uses a private key to embed a watermark image into a cover image, and a watermark-extraction process that uses a public key to extract the watermark from the watermarked image. The embedded watermark can only be extracted by someone who has possession of a proper verification key.

The “anytime, anywhere” concept of human-oriented ubiquitous computing and communication environment (UE) provides an avenue for people to access to everyday devices with some built-in intelligent feature. This allows for them to conveniently access to vast amounts of information including multimedia services in real time from the comfort of their homes e.g. payTV and interactive TV, streaming audiovisuals, video conferencing and video phones, interactive gaming and online merchandising. With this vast amount of multimedia content being distributed in the environment, there is a need to provide protection for the content from piracy and illegal duplication, which is an important security issue if the UE is to gain popularity and widespread usage. One method to provide content protection and tracing of illegal duplications is using buyer-seller watermarking protocols. In particular, owner-specific marks are embedded into the content to allow content protection and buyer-specific marks are embedded to trace illegal duplications. Two such protocols were independently proposed by Chang and Chung, and Cheung , at ICCT 2003 and HICSS 2004, respectively. We show that both the seller’s and buyer’s rights are not protected in both protocols and therefore the protocols fail to provide even the most basic security requirement of buyer-seller protocols. It is important that these protocols not be deployed for securing UE, but to undergo redesign and thorough security analysis before being reconsidered.

Users are interested greatly in a user creative movie (UCM) production among various online contents. The UCM production using music and picture is the method that users make the movie easily. However, the UCM production service has the problem that any association does not exist in the music and picture. To solve this problem, we propose the UCM production method which uses a music analysis and picture analysis in the paper. A music analysis finds a picture change time according to the rhythm. This finds strong part of the sound which uses Root-Mean-Square (RMS). A picture analysis finds the association at each picture and arranges the sequence which the picture appears. This classifies the picture which uses structure simplicity of the picture (SSP) and face region detection. Therefore, if we use a music and picture analysis at the UCM production, users may make natural and efficient movie.

Shadow plays key roles in making images look realistic and you feel spatial sense within the scene. Shadow map and shadow texture are the most famous algorithms for these effects, but both methods have some problems as is well-known. Shadow Map has the aliasing and stripe pattern problem whereas shadow texture algorithm doesn’t have these problems but can not create shadows on themselves (self-shadows). We solved these problems by applying both algorithms at the same time. Our method shows more effective performance and higher quality compared to each existing algorithm.

There are various kinds’ methods to method that image retrieval based on shape feature. In this paper, an efficient content-based image information retrieval method which utilizes shape information and color information is proposed. CSS(Curvature Scale Space) space is used to extract shape information. HSI(Hue Saturation Intensity) space is used to extract color information. This method expresses contours of the object which is binarized through pre-processes in CSS space, then extract shape features of the object in this space. CSS space is a space that expresses curvatures of contours in multiple resolutions, which offers shape features invariant to shift, scale, and skew of the object. HSI color space offers hue and saturation information which is less affected by change of brightness of image. This method gets histogram of the object’s color, and then applies histogram intersection degree to the matching metric in searching process. Show result that image object retrieval being based on process and this that draw CSS information from reflex because an experiment uses ICSS method, and estimate performance by comparing old method and method that propose. The results of experiments show that the proposed method is better in accuracy of searching than existing methods.