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51.
Pulsed photo-stimulated luminescence (PPSL) is a simple screening method that can be employed qualitatively at the spot for the detection of eggs treated with ionizing radiation.Due to the variations in the results during storage,the eggs of ostrich,duck,hen,and quail were irradiated to doses of 0,1,2,and 3 kGy.Most of the samples were incorrectly identified during storage after four months of irradiation.Thermoluminescence (TL) technique was also tried by using egg shells in order to confirm the irradiation treatment in eggs.TL glow curves were recorded between the temperatures 50℃to 400℃at the rate of 5°/s for all the control and irradiated samples.On the basis of integrated areas of first glow curves (TL1),the glow curve ratios (TL1/TL2) and the shapes of maxima of TL1, the irradiation treatment of all the eggs was confirmed.Furthermore,the presence of calcite and aragonite minerals that cause the TL signal in the egg shells were studied using X-ray diffraction spectrometry.  相似文献   
52.
53.
On the Handling of Continuous-Valued Attributes in Decision Tree Generation   总被引:16,自引:0,他引:16  
We present a result applicable to classification learning algorithms that generate decision trees or rules using the information entropy minimization heuristic for discretizing continuous-valued attributes. The result serves to give a better understanding of the entropy measure, to point out that the behavior of the information entropy heuristic possesses desirable properties that justify its usage in a formal sense, and to improve the efficiency of evaluating continuous-valued attributes for cut value selection. Along with the formal proof, we present empirical results that demonstrate the theoretically expected reduction in evaluation effort for training data sets from real-world domains.  相似文献   
54.
The sweepline algorithm has been modified to triangulate a set of nodes on a non-convex domain. The new method is based on a fragile sweepline which is split and rejoined in a manner which ensures that boundaries are preserved. Both the original and the modified algorithms are introduced using simple examples. It is shown that a set of N nodes is triangulated in O(N log N) time. The validity of the new method has been confirmed through testing on a variety of problems, and two test cases are presented in this paper.  相似文献   
55.
Spectrum handoff plays an important role in spectrum management as it is the process of seamlessly shifting the on-going transmission of a secondary user (SU) to a free channel without degrading the quality of service. In this paper, we develop an adaptive handoff algorithm that allows an SU to detect the arrival of a primary user (via sensing) and adapt to a reactive or a proactive handoff strategy accordingly. The adaptive handoff scheme first allows an SU to decide whether to stay and wait on current channel or to perform handoff. Then, in case of handoff, an SU intelligently shifts between proactive or reactive handoff modes based on primary use (PU) arrival rate. Further, a PU prioritized Markov approach is presented in order to model the interactions between PUs and SUs for smooth channel access. Numerical results show that the proposed handoff scheme minimizes the blocking probability, number of handoffs, handoff delay and data delivery time while maintaining channel utilization and system throughput at maximal level compared to simple reactive and proactive schemes.  相似文献   
56.
Multimedia Tools and Applications - The security strength of the elliptic curve cryptosystems (ECC) is due to its core operations-based group law. This aspect of the elliptic curve provides key...  相似文献   
57.

Cloud computing is a popular and widely adopted computing platform for the execution of scientific workflows as it provides flexible infrastructure and offers access to collection of autonomous heterogeneous resources. Effective scheduling of computationally complex workflows which contain many interconnected tasks is a complex problem and becomes more challenging in cloud environment. Optimal solutions can be obtained by considering not only the heterogeneity of computation costs involved, but also by taking into account the communication costs among the tasks in a way that schedule length of the application is reduced. In this paper, we propose a list scheduling heuristic, namely minimal optimistic processing time (MOPT), with optimized duplication approach. The additional feature is introduced for the entry task and is applied only in scenarios in which duplication is more practical and effective. The prioritization phase of the proposed work is based on an optimistic processing time matrix that is used for ranking of the tasks. The algorithm has same time complexity as state-of-the-art existing algorithms, but notable improvements are acquired in terms of makespan and other performance evaluation parameters. Extensive experimental analysis of the proposed algorithm is carried out using synthesized graphs and graphs from the real-world applications. The results prove that MOPT achieves quality schedules with reduced makespans. As communication cost among the tasks grows higher, performance of the proposed algorithm becomes more effective, thus providing the evidence that the MOPT algorithm is well-suited for communication-intensive applications.

  相似文献   
58.
Mobile Networks and Applications - Over the last few years, context-aware computing has received a growing amount of attention among the researchers in the IoT and ubiquitous computing community....  相似文献   
59.
This paper demonstrates the design procedure of a 4 × 8 phased array antenna. Initially, a unit element in multilayer topology with orthogonal slots in the ground plane to couple electromagnetic energy is designed. Then, a stacked patch with truncated edges is placed on the top thick substrate layer to enhance the bandwidth to 600 MHz. This multilayered stacked patch unit element is then used to design a 1 × 4 and 4 × 8 slot coupled stacked patch array. On the bottom side, a novel feedline structure is designed to provide a 90 o phase difference at the antenna feed for the circular polarization. The phase difference is achieved in the feedline structure using a quarter wavelength ( λg/4 ) difference in the lengths. After the numerical validation, both 1 × 4 and 4 × 8 stacked patch antenna arrays are fabricated to validate the simulations. The final 4 × 8 array achieved the target specification of an active reflection of less than ?10 dB over 2.4 to 3.0 GHz, axial ratio of less than 3 dB, and stable radiation pattern over the complete band. In addition, beam scanning characteristics of the proposed stacked patch antenna arrays are also verified. The prototype resulted a peak gain of 19.5 dB at 2.7 GHz, 3‐dB beamwidth around 12 o in the xz‐plane, and scanning range of 90 o . Overall, good agreement between measured and simulated results showed that the proposed designed array capable of providing 600 MHz is an excellent candidate for the radar communication, small commercial drones, and synthetic aperture radar applications.  相似文献   
60.
International Journal of Control, Automation and Systems - Dissimilar redundant actuation systems (DRAS) are in practice in advanced aircraft in order to increase reliability and to resolve the...  相似文献   
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