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Finding Reasons and Conclusion in a Basic Computer Science Course
Get PDFThis paper discusses infusing the critical thinking skill of finding reasons and conclusions in a basic computer science course, ICS 201: Introduction to CS, which is the second course in the series of three introductory courses in our curriculum [8]. Software engineers usually use certain design in a program or algorithm without fully considering the effects of that decision. The critical thinking skill of finding reasons and conclusions enable them to reason more about their choice of design. Also, it helps them to convince the proponent to follow the decision they made with conviction
Arabic Diacritics Based Steganography
Get PDFNew steganography methods are being proposed to embed secret information into text cover media in order to search for new possibilities employing languages other than English. This paper utilizes the advantages of diacritics in Arabic to implement text steganography. Diacritics - or Harakat - in Arabic are used to represent vowel sounds and can be found in many formal and religious documents. The proposed approach uses eight different diacritical symbols in Arabic to hide binary bits in the original cover media. The embedded data are then extracted by reading the diacritics from the document and translating them back to binary
Area Flexible GF(2k) Elliptic Curve Cryptography Coprocessor
Get PDFElliptic curve cryptography (ECC) is popularly defined either over GF(p) or GF(2k). This research modifies a GF(p) multiplication algorithm to make it applicable for GF(2k). Both algorithms, the GF(p) and GF(2k) one, are designed in hardware to be compared. The GF(2k) multiplier is found faster and small. This GF(2k) multiplier is further improved to benefit in speed, it gained more than 40% faster speed with the cost of 5% more area. This multiplier hardware is furthermore adjusted to have area flexibility feature, which is used as the basic block in modeling a complete projective coordinate GF(2k) ECC coprocessor
Design of two step deterministic interleaver for turbo codes
No full textThe performance and design of a deterministic interleaver for short frame turbo codes is considered in this paper. The main characteristic of this class of deterministic interleaver is that their algebraic design selects the best permutation generator such that the points in smaller subsets of the interleaved output are uniformly spread over the entire range of the information data frame. It is observed that the interleaver designed in this manner improves the minimum distance of first few spectral lines of minimum distance spectrum. Finally we introduce a circular shift in the permutation function to reduce the correlation between the parity bits corresponding to the original and interleaved data frames to improve the decoding capability of MAP decoder. The design is focused on combining good permutations with de-correlation property. Our solution to design a deterministic interleaver outperforms the semi-random interleavers and the deterministic interleavers reported in the literature
Harmonic and Intermodulation Performance of the Semiconductor Bolometer
Get PDFA mathematical model for the temperature dependence of the bolometer semiconductor resistance is presented. The model, basically a sine-series function, can easily yield closed-form expressions for the harmonic and intermodulation performance of the acquired interferogram voltage with large-amplitude multisinusoidal variations in the incident radiation. The special case of two-tone equal-amplitude incident radiation is considered in detail. The results show that the intermodulation components are always higher than the harmonic components of the same order. The results also show that the second-order intermodulation is always dominant and is higher than the second-harmonic component by about 6 dB. Moreover, the results show that for relatively small incident amplitudes of the incident radiation the ratio between the second- and third-harmonic components is almost equal to the ratio between the second-harmonic component and the fundamental. The results also show that the ratio between the amplitudes of the second- and third-order intermodulation components is almost equal to the ratio between the amplitudes of the second-order intermodulation component and the fundamental
Parameter Optimization of Shunt FACTS Controllers for Power System Transient Stability Improvement
Get PDFTo enhance power system transient stability, shunt FACTS devices can be controlled in discontinuous mode or in a combination of discontinuous and continuous mode. In continuous mode proportional controller is usually used. This paper investigates the performance of others controllers in continuous mode. Two additional controllers – PI and lead-lag, have been considered. Controller parameter values have been optimized for minimum settling time. This study shows that both PI and lead-lag controllers have good potential for improving critical clearing time. It also shows that properly selected controller parameter values can reduce settling time significantly. The obtained results are verified using non-linear time-domain simulation for both single-machine infinite-bus (SMIB) and multi-machine (10 machine 39 bus) case