Optimizing cooperative cognitive radio networks with opportunistic access

Optimal resource allocation for cooperative cognitive radio networks with opportunistic access to the licensed spectrum is studied. Resource allocation is based on minimizing the symbol error rate at the receiver. Both the cases of all-participate relaying and selective relaying are considered. The objective function is derived and the constraints are detailed for both scenarios. It is then shown that the objective functions and the constraints are nonlinear and nonconvex functions of the parameters of interest, that is, source and relay powers, symbol time, and sensing time. Therefore, it is difficult to obtain closed-form solutions for the optimal resource allocation. The optimization problem is then solved using numerical techniques. Numerical results show that the all-participate system provides better performance than its selection counterpart, at the cost of greater resources

A Novel Method of Home Energy Management System Using Microcontroller for Increasing Load Factor

The development of any country depends to a large extent on availability and usage of electricity. Conservation of electricity has now become a vital element of economic growth giving benefit to state’s exchequer and this conservation is more essential due to the concern for fast depletion of non-renewable sources of energy in the country. The main aim of this paper is to construct a control system that can manage (turn on/off and control speed) various common home appliances like Heater, Fan, Air Conditioner etc of domestic load at instantaneous time. The potential transformer is used to measure voltage and a current transducer is used to measure a current flow through load, further it communicates with microcontroller using one analog to digital converter

Studi Literatur : Perbandingan Ssl, Set, Sep Berdasarkan End-user Implementation Requirements

Sistem pembayaran elektronik (e-payment) dianggap sebagai tulang punggung e-commerce. Agar diterima secara luas metode pembayaran di seluruh dunia, sistem e-payment harus mengikuti protokol keamanan yang efisien yang menjamin keamanan yang tinggi untuk transaksi online. Secure Socket Layer (SSL) dan Secure Electronic Transaction (SET) merupakan dua protokol yang banyak dibahas untuk mengamankan pembayaran kartu kredit online. Namun, SSL maupun SET telah gagal dalam implementasi pada pengguna akhir, sehingga munculah protokol Secure Electronic Payment (SEP) yang merupakan protokol e-payment yang aman dan efisien yang menawarkan lapisan tambahan perlindungan bagi cardholder dan merchant. Tujuan penulisan ini untuk menentukan protokol mana yang paling cocok untuk keamanan e-payment berdasarkan perbandingan pada end-user implementation requirements. Metode yang digunakan berupa studi literatur dengan melihat karya terkait yang membahas mengenai protokol SSL, SET, SEP yang selanjutnya akan dilakukan perbandingan. Hasil yang didapatkan dari perbandingan protokol keamanan e-payment SSL, SET, dan SEP berdasarkan faktor end-user implementation requirements (USAbility, flexibility, affordability, reliability, availability, interoperability) yaitu bahwa protokol SEP yang memenuhi syarat dan paling cocok untuk diterapkan dalam keamanan e-payment

Constrained RS coding for Low Peak to Average Power Ratio in FBMC -- OQAM Systems

Multi-carrier modulation techniques have now become a standard in many communication protocols. Filter bank based multi-carrier (FBMC) generation techniques have been discussed in the literature as a means for overcoming the shortcomings of IFFT/FFT based OFDM system. The Peak to Average Power Ratio (PAPR) is a problem faced by all multi-carrier techniques. This paper discusses the methods for reducing PAPR in a FBMC system while maintaining acceptable Bit Error Rate (BER). A new PAPR minimizing scheme called Constrained Reed Solomon (CRS) coding is proposed. The hybrid techniques using coding and companding are tested for different channel models and is found to yield promising results.Comment: 6 pages,6 Figures, Journal of Electrical and Electronics Engineerin

Towards a Generic Context Model for BPM

International audienceThis paper introduces a new context modeling approach for the business process management field. The proposed approach aims at identifying and formalizing the contextual knowledge relevant to business processes in order to be able to adapt business processes according to the context. This approach has the particularity to be generic and extensible; it can be integrated with many business process modeling approaches. It is based on ontologies and has two layers, i.e. generic layer and specific layer. Throughout the paper we compare the proposed approach with the related work in order to clearly demonstrate why we propose this approach

The SS-SCR Scheme for dynamic spectrum access

We integrate the two models of Cognitive Radio (CR), namely, the conventional Sense-and-Scavenge (SS) Model and Symbiotic Cooperative Relaying (SCR). The resultant scheme, called SS-SCR, improves the efficiency of spectrum usage and reliability of the transmission links. SS-SCR is enabled by a suitable cross-layer optimization problem in a multihop multichannel CR network. Its performance is compared for different PU activity patterns with those schemes which consider SS and SCR separately and perform disjoint resource allocation. Simulation results depict the effectiveness of the proposed SS-SCR scheme. We also indicate the usefulness of cloud computing for a practical deployment of the scheme