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排序方式: 共有514条查询结果,搜索用时 15 毫秒
11.
In this paper, a digital filter bank structure is proposed for the reconstruction of uniformly sampled bandlimited signals from their N-th order nonuniform samples. The proposed filter bank structure is arrived at after incorporating polyphase-domain filtering operations and discrete Fourier transform (DFT) modulation to an existing filter bank framework.In this paper, an idea is also presented, so that uniform samples can be reconstructed from N-th order nonuniform samples using the structures based on recurrent nonuniform sampling. A comparison of the computational complexity and the signal-to-noise ratio (SNR) performance is also given for various structures existing in the literature. 相似文献
12.
A. R. Usha Devi A. K. Rajagopal Sudha H. S. Karthik J. Prabhu Tej 《Quantum Information Processing》2013,12(12):3717-3723
Classical and quantum world views differ in peculiar ways. Understanding decisive quantum features—for which no classical explanation exist—and their interrelations is of foundational interest. Moreover, recognizing non-classical features carries practical significance in information processing tasks as it offers insights as to why quantum protocols work better than their classical counterparts. We focus here on two celebrated notions of non-classicality viz., negativity of P phase–space representation and entanglement in symmetric multiqubit systems. We prove that they imply each other. 相似文献
13.
In today's Internet routing infrastructure, designers have addressed scaling concerns in routing constrained multiobjective optimization problems examining latency and mobility concerns as a secondary constrain. In tactical Mobile Ad-hoc Network (MANET), hubs can function based on the work plan in various social affairs and the internally connected hubs are almost having the related moving standards where the topology between one and the other are tightly coupled in steady support by considering the touchstone of hubs such as a self-sorted out, self-mending and self-administration. Clustering in the routing process is one of the key aspects to increase MANET performance by coordinating the pathways using multiple criteria and analytics. We present a Group Adaptive Hybrid Routing Algorithm (GAHRA) for gathering portability, which pursues table-driven directing methodology in stable accumulations and on-request steering strategy for versatile situations. Based on this aspect, the research demonstrates an adjustable framework for commuting between the table-driven approach and the on-request approach, with the objectives of enhancing the output of MANET routing computation in each hub. Simulation analysis and replication results reveal that the proposed method is promising than a single well-known existing routing approach and is well-suited for sensitive MANET applications. 相似文献
14.
The Stanford Hydra CMP 总被引:5,自引:0,他引:5
The Hydra chip multiprocessor (CMP) integrates four MIPS-based processors and their primary caches on a single chip together with a shared secondary cache. A standard CMP offers implementation and performance advantages compared to wide-issue superscalar designs. However, it must be programmed with a more complicated parallel programming model to obtain maximum performance. To simplify parallel programming, the Hydra CMP supports thread-level speculation and memory renaming, a paradigm that allows performance similar to a uniprocessor of comparable die area on integer programs. This article motivates the design of a CMP, describes the architecture of the Hydra design with a focus on its speculative thread support, and describes our prototype implementation. Chip multiprocessors offer an economical, scalable architecture for future microprocessors. Thread-level speculation support allows them to speed up past software 相似文献
15.
In modern electronics manufacturing, many of the assembly operations require the use of microscopes. This paper presents measures and suggestions that could help in relieving visual and postural fatigue in microscope work. These measures include the ergonomic design of microscope workstations as well as of microscopes themselves, process changes to minimise use of the microscope, replacement of microscope workstations with television systems, and a training programme for inexperienced operators. The main emphasis in implementing these recommendations was the ergonomic design of microscope workstations; several examples are given. 相似文献
16.
Prasad K P BK Chakravarthy M Prabhu G 《Computer methods and programs in biomedicine》2012,106(1):27-36
This paper demonstrates the use of TissueQuant - an image analysis tool for quantification of color intensities which was developed for use in medical research where the stained biological specimen such as tissue or antigen needs to be quantified. TissueQuant provides facilities for user interaction to choose and quantify the color of interest and its shades. Gaussian weighting functions are used to provide a color score which quantifies how close the shade is to the user specified reference color. We describe two studies in medical research which use TissueQuant for quantification. The first study evaluated the effect of petroleum-ether extract of Cissus quadrangularis (CQ) on osteoporotic rats. It was found that the analysis results correlated well with the manual evaluation, p < 0.001. The second study evaluated the nerve morphometry and it was found that the adipose and non adipose tissue content was maximum in radial nerve among the five nerves studied. 相似文献
17.
The technique of high resolution microautoradiography has already been applied to study the microsegregation of carbon and tritium in iron and its alloys, but autoradiographs have so far been obtained using liquid nuclear emulsions and carbon replicas on massive specimens. This technique has now been extended to study the distribution of carbon in thin foil microstructures of a 12% chromium steel in the quenched and tempered condition. An experimental procedure has been developed for obtaining autoradiographs on thin foils, and is described in detail. The limitations of the technique with respect to efficiency and resolution have been considered. The results obtained show that high resolution microautoradiography on thin foils permits a more precise localization of the radioactive tracer atoms with respect to the microstructural features and gives a better resolution, even with a radioisotope emitting high energy particles, in comparison with the replica method on massive specimens. 相似文献
18.
Jannatul Aklima Sawaros Onchaiya Tomonori Saotome Punitha Velmurugan Taihei Motoichi Jannatul Naima Yutaka Kuroda Yoshihiro Ohta 《International journal of molecular sciences》2022,23(17)
Protein quality control is essential for cellular homeostasis. In this study, we examined the effect of improperly folded proteins that do not form amyloid fibrils on mitochondria, which play important roles in ATP production and cell death. First, we prepared domain 3 of the dengue envelope protein in wild type and four mutants with widely different biophysical properties in misfolded/aggregated or destabilized states. The effects of the different proteins were detected using fluorescence microscopy and Western blotting, which revealed that three of the five proteins disrupted both inner and outer membrane integrity, while the other two proteins, including the wild type, did not. Next, we examined the common characteristics of the proteins that displayed toxicity against mitochondria by measuring oligomer size, molten globule-like properties, and thermal stability. The common feature of all three toxic proteins was thermal instability. Therefore, our data strongly suggest that thermally unstable proteins generated in the cytosol can cause cellular damage by coming into direct contact with mitochondria. More importantly, we revealed that this damage is not amyloid-specific. 相似文献
19.
Strictly periodic scheduling in IMA-based architectures 总被引:1,自引:0,他引:1
Ahmad Al?Sheikh Olivier Brun Pierre-Emmanuel Hladik Balakrishna J. Prabhu 《Real-Time Systems》2012,48(4):359-386
The avionic industry has recently adopted the Integrated Modular Avionics (IMA). Such architectures allow the execution of avionic functions on a shared computing platform while avoiding any interference between them. This is done through hard memory and temporal segregation constraints. Although IMA reduces the weight and the power consumption and shortens the design-cycle times, it gives rise to a complex multiprocessor scheduling problem. One of the key difficulties of this problem is related to the strict periodicity of tasks, which means that the time separating two successive executions of the same task is strictly equal to the associated period. In order to help the system designer in producing a proper schedule, an exact formulation based on Integer Linear Programming and a heuristic inspired from Game Theory are proposed. To enhance the solution quality of the heuristic, a?multi-start method, which gives some probabilistic guarantees on the optimality of the solutions, is also introduced. 相似文献
20.
Thermal analysis of LM29 alloy and Ce added LM29 alloys was carried out. The effect of cerium addition on solidification parameters and microstructural features of hypereutectic Al-Si (LM29) alloy was studied using Newtonian analysis technique. Thermal analysis parameters such as primary and eutectic phase nucleation and solidus temperatures were determined. The addition of Ce to LM29 alloy decreased the nucleation temperature of primary silicon and eutectic silicon. The microstructural examination of Ce added LM29 alloys revealed the presence of a polyhedral shaped Al–Si–Ce compound that might have caused the refinement of primary and eutectic silicon. The dendrite coherency point temperature of LM29 alloy was found to be suppressed on addition of Ce. 相似文献