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This paper presents a personal perspective on the most recent disclosures on how information technology was used to break laws, to change buyers' behaviour by making them buy new and more expensive products, or even risking the safety and the life of the consumers and other people.

All-inclusive system became very popular in the last decades due to the some advantages for tourists. It was adopted both by luxury locations and by more modest locations in emerging economies, as Bulgaria and Romania. The last ones offer a variety of decent services at affordable costs for large category of people. The low cost involves better management of the resources, which aims to reduce the waste and preserving the appearance of plenty. This paper presents a computer-based solution that allows tourists monitoring within a resort and provides some useful online functions as well as offline functions. The solution we propose relies on available technologies, such as RFID tags and readers, database management systems and computer based communication systems.

One of the most present issues of computer wireless networks is the security. Comparing with their wired counterpart, the wireless networks not only accentuate some of the well-known security vulnerabilities but they are subject of new and specific ones. Among the existing wireless networks the ad hoc ones are the most exposed to attacks and collusions due to the absence of any centralized control. The most efficient way to ensure the communication secrecy, inclusively for ad hoc wireless networks, is the cryptography. From many reasons, following from specific operating conditions, the employment of asymmetric key techniques and Public Key Infrastructure is not a realistic choice. In the networks with a large number of nodes, as wireless sensor networks, a large number of secret keys are involved in order to ensure the communication secrecy. While dynamicity is one of the essential features of mobile wireless networks, when nodes may leave or join the network and in the absence of a centralized control entity, the management of secret keys is crucial. The paper presents the main aspects of mobile wireless networks security and focuses on the key management issue in ad-hoc wireless networks.

This paper presents an innovative solution in retail activities, named "Intelligent Store - INTELSHOP", based on a technological platform that offers the support for some attractive and efficient services for customers and administrative staff. The technological platform integrates various technologies such as RFID, GPS and GIS, wireless communications, mobile access to information on PDA or SmartPhone, integrated environments for data analysis regarding stocks and customers administration, interfaces with electronic payment systems. The goal pursued is mainly to reduce the time wasted by the customers searching the products on the store's shelf, to offer more and better information about products. On the other hand our solution pursues to maximize the merchant benefit by reducing the provisioning time, to diversify the offer and to create the opportunity to make the best decision in real time.

This paper presents two current-mode circuits which provide frequency multiplication for sinusoidal input signals. The circuits are based on translinear topologies that ensure high performances concerning frequency range, linearity and temperature stability. No selective circuits or signal conditioners are required.

This paper presents a topology for a second-order current-mode active filter based on current-followers. Compared to other similar circuits presented in literature, the new topology provides low input impedance that makes possible the connection in cascade of two or many similar circuits without additional current buffers. Hence the circuit uses only two current followers and a reduced number of passive components: two capacitors and two or three resistors, depending on the required transfer function. By choosing appropriate values for the circuit's admittance it is possible to achieve the three most important transfer functions: low-pass, high-pass and band-pass.