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991.
992.
Semiconductors - Due to the lack of work in structures containing thallium (Tl), this work is devoted to study of Ga8Tl2N quantum-dot photodetectors. Parameters are specified first. This structure... 相似文献
993.
Amani Alahmadi Muhammad Hussain Hatim Aboalsamh Ghulam Muhammad George Bebis Hassan Mathkour 《Signal, Image and Video Processing》2017,11(1):81-88
With the development of easy-to-use and sophisticated image editing software, the alteration of the contents of digital images has become very easy to do and hard to detect. A digital image is a very rich source of information and can capture any event perfectly, but because of this reason, its authenticity is questionable. In this paper, a novel passive image forgery detection method is proposed based on local binary pattern (LBP) and discrete cosine transform (DCT) to detect copy–move and splicing forgeries. First, from the chrominance component of the input image, discriminative localized features are extracted by applying 2D DCT in LBP space. Then, support vector machine is used for detection. Experiments carried out on three image forgery benchmark datasets demonstrate the superiority of the method over recent methods in terms of detection accuracy. 相似文献
994.
ABSTRACT Drying studies were carried out on single droplets of gelatin solution, typifying a skin forming, heat-sensitive material. Each droplet was suspended from a novel rotating glass nozzle which enabled direct measurement of its weight and temperature during drying. Observations using this appartatus successfully detected the decrease in core temperature and increase in drying rate resulting from granule dissolution at 30 °C. The study covered air temperatures in the range 19 °C–175 °C. Scanning Electron Microscopy was used to examine the dried crusts. The resistance of the skin to vapour diffusion was significantly increased with an increase in the air temperature. At air temperature > 60 °C the dried particle lost the structure and properties of the original powder. The optimum drying conditions to avoid this were predicted for this type of skin forming-material. 相似文献
995.
There has been a growing mismatch between household and housing types in Australian cities in recent years. At the same time housing has become increasingly expensive, while low-density urban development has meant increasing social and economic costs for households in fringe suburbs. This paper explores current housing and location preferences of Adelaide residents. The findings suggest that home ownership and the single-storey detached dwelling are well entrenched preferences among residents, and that as yet, the personal costs of the linear spread of the city have not impacted significantly on housing and location preferences. 相似文献
996.
997.
Kaveh Abookazemi Hussein AhmadAlireza Tavakolpour Mohd Y. Hassan 《International Journal of Electrical Power & Energy Systems》2011,33(4):969-975
This paper presents an investigation into the application of an optimized Genetic Algorithm (GA) to solve the Thermal Unit Commitment (UC) problem. A Parallel structure was first developed to handle the infeasibility problem in a structured and improved GA which provides an effective search process and therefore greater economy. The proposed methodology resulted in a better performance with faster operation by using both computational methods and classification of unit characteristics. Typical constraints such as system power balance, minimum up and down times, start-up and shut-down ramps, have also been considered. A number of important parameters (standard and new parameters) of the UC problem have been identified. The proposed method is implemented and tested using a C# program. The tests are carried out using two systems including 10 and 20 units during a scheduling period of 24 h. The results are finally compared with those obtained from genetic schemes in other similar investigations through which the effectiveness of the proposed scheme is affirmed. 相似文献
998.
Nicoleta Wacker Harald RichterMahadi-Ul Hassan Horst RemppJoachim N. Burghartz 《Solid-state electronics》2011,57(1):52-60
This paper presents a novel implementation of variable uniaxial mechanical stress model to be used with DC circuit simulation, e.g. using BSIM3v3 transistor model. Based on transistor measurements under various uniaxial stress conditions two stress-dependent parameters are identified, namely the carriers mobility and to a lesser extend the carrier saturation velocity. The effect of the parasitic source/drain resistance on the piezoresistive coefficient determination is addressed in detail. Using the fundamental piezoresistive coefficients, the model has implemented a general relation to calculate the coefficients for arbitrary directions of current and stress in the (0 0 1) silicon (Si) plane. The extended transistor model allows for simulating the effect of uniaxial stress on any MOSFET geometry, under different operation conditions and for any combination of the drain current and stress orientations in the (0 0 1) silicon (Si) plane. The method proposed in this paper is validated by static and dynamic stress-dependent simulations and comparison with experimental data. The method is simulator-independent and can be adapted to other bulk CMOS technologies including SOI processes. 相似文献
999.
Hassan Ahmed Nazar Abdullah Abdul Hanan Kaiwartya Omprakash Cao Yue Sheet Dalya Khalid 《Wireless Networks》2018,24(7):2763-2779
Wireless Networks - Maintaining durable connectivity during data forwarding in Vehicular Ad hoc Networks has witnessed significant attention in the past few decades with the aim of supporting most... 相似文献
1000.
Video streaming over peer-to-peer (P2P) networks is a promising approach for scalable IPTV and online games. Distributing high-quality videos among users who employ numerous channels in multi-channel P2P live streaming systems, however, still suffers from many challenges arisen from the network size and dynamicity, channel resource imbalance, and bandwidth limitations. Other challenges also exist, including instability of peers, the peers’ low participation, large startup and playback delays, low quality of received video, and resource insufficiency in unpopular channels. In this paper, ReDePoly, with some levels of distributed intelligence, is proposed to reduce the bootstrapping delay and to increase the service quality. The key idea is to substitute agents with bootstrapping peers in the channels to model user behaviors and to share the aggregated knowledge among the agents to disseminate the learned models. Accordingly, the agents dynamically predict the behavior of participating peers to pre-assign them to the predicted channels and to parallelize the threads related to viewing behavior and channel switching. In case of congested channels, the new agents are distilled to mitigate the agent responsibilities. Simulation results show that the proposed approach outperforms the other existing methods regarding the channel switching delay, recovery delay, and quality of service. 相似文献