به نام خدا
Title: Agile and Efficient MIMO System for Smart Phone Terminals
Authors: Osama N Alrabad, Elpiniki P Tsakalaki, Mauro Pelosi, Gert F Pedersen
Abstract: The paper proposes a novel multi-input multi-output (MIMO) system architecture that covers most of the high L TE bands. The system is comprised of four small loop antennas. Each antenna has two ports, one for communication and one for control. The control port is used for tuning the loop antenna where impressive frequency agility using a single capacitor is obtained. A good level of inherent isolation among the four loop antennas is maintained over the different frequency bands. The MIMO performance of the proposed system is evaluated through its spectral efficiency versus frequency. Finally, the information bandwidth of the MIMO system can be defined by comparing its spectral efficiency against the spectral efficiency of three ideal MIMO antennas.
Publish Year: 2013
Published in: iWat - IEEE
Number of Pages: 4
موضوع: تلفنهای هوشمند
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به نام خدا
Title: Interface-Based Object-Oriented Design with Mock Objects
Authors: Nandigam, J.; Gudivada, V.N.; Hamou-Lhadj, A.; Yonglei Tao
Abstract: Interfaces are fundamental in object-oriented systems. One of the principles of reusable object-oriented design, according to Gamma et al., is program to an interface, not an implementation. Interface-based systems display three key characteristics - flexibility, extensibility, and pluggability. Designing with interfaces is therefore a better way of building object-oriented systems. Getting students in introductory software engineering and design courses to program to interfaces and develop interface-based systems is a challenge. This paper presents our experiences with the use of mock objects to promote interface-based design and effective unit testing in software engineering and design courses.
Publish Year: 2009
Publisher: ITNG - IEEE
Number of Pages: 6
موضوع: طراحی و تحلیل شی گرا
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به نام خدا
Title: Low Complexity Routing Algorithm for Rearrangeable Switching Networks
Authors: Amitabha Chakrabarty Martin Collier
Abstract: Rearrangeable switching networks have been a topicof interest for a long time among the research community.Routing algorithms for this class of networks have attractedlots of researchers along with other related areas, such asmodiï¬cation of the networks structure, crosspoints reduction etc.In this paper a new routing algorithm is presented for symmetricrearrangeable networks built with 2 × 2 switching element. Anew matrix based abstraction model is derived to determineconflict free routing paths for each input-output request. Eachstage of a network is mapped into a set of sub-matrices andnumber of matrices in each stage correspond to number ofsubnetworks in that stage. Once the input permutation is given,matrix cells are populated with binary values depending onthe position of the switching elements in the actual hardwareand their mapped matrix cells. These binary values control therouting decision in the underlying hardware. This new routingalgorithm is capable of connection setup for partial permutation,m = ÏN , where N is the total input numbers and m is thenumber of active inputs. Overall the serial time complexity ofthis method is O(N logN)1 and O(mlogN) where all N inputsare active and with m < N active inputs respectively. Thetime complexity of this routing algorithm in a parallel machinewith N completely connected processors is O(log2N). With mactive requests the time complexity goes down to O(logmlogN),which is better than the O(log2m + logN), reported in theliterature for 212[(log2Nâˆ_4logN)12âˆ_logN ] ≤ Ï â‰¤ 1. Later half ofthis paper demonstrates how this routing algorithm is applicablefor crosstalk free routing in optical domain.
Publish Year: 2013
Publisher: AINA - IEEE
Number of Pages: 8
موضوع: الگوریتم مسیر یابی، شبکه های کامپیوتری
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به نام خدا
Title: Noise Robust Voice Detector for Speaker Recognition
Authors: Gabriel Hernandez, Jose R Calvo, Rafael Fernandez, Ivis Rodes and Rafael Martnez
Abstract: The effect of additive noise in a speaker recognition system is well known to be a crucial problem in real life applications. In a speaker recognition system, if the test utterance is corrupted by any type of noise, the performance of the system notoriously degrades. The use of a noise robust voice detector to determine which audio frame is a voice frame is proposed in this work. The new detector is implemented using an Ada-Boosting algorithm in a voiced-unvoiced sound classifier based on speech waveform only. Results reflect better performance of robust speaker recognition based on selected voice segments, respects to unselected segments, in front to additive white noise.
Publish Year: 2008
Publisher: ICPR - IEEE
Number of Pages: 4
موضوع: تشخیص صدا
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به نام خدا
Title: Accelerating Pollard’s Rho Algorithm on Finite Fields
Authors: Jung Hee Cheon, Jin Hong , and Minkyu Kim
Abstract: Most generic and memory efficient algorithms for solving the discrete logarithm problem construct a certain random graph consisting of group element nodes and return the solution when a collision is found among the graph nodes. In this work, we develop a technique for traveling through the random graph with- out fully computing each node and also provide an extension to the distinguished point collision detection method that is suitable for this new situation. Concrete constructions of this technique for multiplicative subgroups of the finite fields are given. Our implementations confirm that the proposed technique provides practical speedup over existing algorithms.
Publish Year: 2012
Publisher: Journal of Cryptography - Journal of Springer
Number of Pages: 48
موضوع: میدانهای متناهی، جبر مجرد، رمزنگاری
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