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A new testbed was developed with an LSNA to perform multi-harmonic broadband measurements for periodically modulated signals with bandwidth exceeding the IF receiver bandwidth of the LSNA. This testbed is intended for characterizing PAs using periodically modulated (multitone) signals often referred as multisines. Multisine signals can be synthesized to approximate the CCDF and PAPR of digitally modulated...
Traditional security models and single security technology cannot keep up with the change of complicated network structure and varied intrusion measure. Network security manage based on optimization has traits of low manage cost, high agility, wide applicability. This paper introduces network security management based on non-optimum system theory into new network security model, and emphases on its...
Local search (LS) algorithms are among the most powerful techniques for solving computationally hard problems in combinatorial optimization. These algorithms could be viewed as ??walks through neighborhoods?? where the walks are performed by iterative procedures that allow to move from a solution to another one in the solution space. In these heuristics, designing operators to explore large promising...
Optimizing the indices and values of free subcarriers (FSs) can significantly reduce the peak-to-average power ratio (PAR) of orthogonal frequency division multiplexing (OFDM) signals. In this paper, a numerical method is proposed to analyze the average PAR reduction performance of the FS optimization method. Different PAR reduction performance is revealed for different FS index assignments and the...
This paper considers two problems in sparse filter design, the first involving a least-squares constraint on the frequency response, and the second a constraint on signal-to-noise ratio relevant to signal detection. It is shown that both problems can be recast as the minimization of the number of non-zero elements in a vector subject to a quadratic constraint. A solution is obtained for the case in...
Traditional algorithm for resource leveling optimization is based on the resource allocation pattern which is conventional distribution, i.e. the amount of resource invested is constant through the time when the leveling activity is underway. However, that assumption is always incompatible with practical working pattern of resource. In practice, resource allocation varies often with different features...
Many modern optimizers use a transformation rule based framework. While there has been a lot of work on identifying new transformation rules, there has been little work focused on empirically evaluating the effectiveness of these transformation rules. In this paper we present the results of an empirical study of "profiling" transformation rules in Microsoft SQL Server using a diverse set...
Statistical analysis of massive data is becoming indispensable to science, commerce, and society today. Such analysis requires efficient, flexible storage support and special optimization techniques. In this demo, we present RIOT (R with I/O Transparency), a system that extends R, a popular computing environment for statistical data analysis. RIOT makes R programs I/O-efficient in a way transparent...
According to the characteristics of wind power industry itself and wind farm production operation and economic index being used, this article proposes annual comprehensive electricity consumption ratio, power ratio, capacity coefficient, loss coefficient, unit reactive consumption, 1 kwh comparable operation cost six indexes. And this article also makes comprehensive evaluation for operation economy...
A major problem in mobile computing is the optimal replication and location of data files in the Grid sites, in order to improve and maintain over time a high overall throughput of Grid jobs that access files. Therefore, a Grid optimization service should be able to dynamically modify the geographic distribution of data files, triggering file replication and location, according to the variation over...
We demonstrate ROX, a run-time optimizer of XQueries, that focuses on finding the best execution order of XPath steps and relational joins in an XQuery. The problem of join ordering has been extensively researched, but the proposed techniques are still unsatisfying. These either rely on a cost model which might result in inaccurate estimations, or explore only a restrictive number of plans from the...
In this paper we employ Structural Similarity Index (SSIM) metric in the rate-distortion optimizations of H.264 strictly I-frame encoder to choose the best prediction mode(s). The SSIM is designed to improve on traditional metrics like PSNR and MSE, which have been proved to be inconsistent with human eye perception. The required modifications are done on the JVT reference software JM92 program. The...
This paper presents an analytical method for quantitative performance analysis and configuration optimization for the cooperation of multiple nonholonomic mobile manipulators to transport a common object. The major challenge of such cooperation comes from the requirement of tight physical interactions between the robotic agents through a payload. The cooperation as a mobile constrained articulation...
For differential unitary space-time modulation (DUSTM), the bit-error performance is affected by the type of labeling. In this paper, we used the Binary Switching Algorithm (BSA) to optimize the labeling of cyclic constructed DUSTM constellation. Instead of time-consuming simulation, we constructed an easily-calculated cost function to estimate the impact of different types of labeling on the bit-error...
Focus on the randomicity of wind speed and river flow rate, meanwhile let the base data easily get especially in the rural area of China, a general random chance constrained optimization model is build which takes hour as time interval, average value of a month as a typical day and simulates every hour's power flow, then generates automatically several plans that will meet users' demands under the...
With the availability of ever-increasing gene sequence data across a large number of species, reconstruction of phylogenetic trees to reveal the evolution relationship among those species becomes more and more important. In this paper, we present a novel proof of the NP-completeness of the large parsimony problem by reduction from a newly-proved NP-complete problem to gain additional insight of this...
The topic of tuition fees has recently sparked heated discussions in various media. Based on China's national conditions, this article collected elevant data, such as national student average funding, training costs, household disposable income and did the quantitative analysis for tuition standards of several types of schools, then built a Multi-level fuzzy evaluation model, which regarded the tuition...
In gene analysis, finding approximate tandem repeats in DNA sequence is an important issue. MSATR is one of the latest methods for finding those repetitions, which suffers deficiencies of runtime cost and poor result quality. This paper proposes an optimized algorithm mMSATR for detecting approximate tandem repeats in genomic sequences more efficiently. By introducing the definition of CASM to reduce...
In order to find a more effective method of solving the problem of subjectivity and difficulty to deal with the high-dimension data in the clustering, a new method---an improved PP (Projection Pursuit) based on Ant Colony Optimization algorithm (ACO) was introduced. The ant colony optimization algorithm has the strong global optimization ability and the PP method is a powerful technique for extracting...
The problem of designing optimal opportunity-awaiting control strategy for a class of stochastic systems is considered in this note. The performance specifications, such as sector pole region, average waiting time and average residue time indexes, constitute the desired performance index set, which is the requirement of designing controllers. The desired closed-loop poles are restricted in a proper...
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