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271.
This paper investigates specific systems with overflow traffic. A primary group with two Poisson traffics is considered whereupon the rejected calls from one traffic are directed to the alternative group with changed serving intensities. The generating function technique is used for analytical solving the model with secondary and ternary groups and the model that separately treated the channels in alternative groups. The obtained analytical solutions essentially reduce the constraints concerning the equation system size, convergence, and calculation time, which arise when numerically solving the steady-state system equations. For the case with single channels in the ternary group, explicit solutions for traffic parameters are obtained. Also, comparison with the model that has a unique serving intensity of overflow traffic is made.  相似文献   
272.
Ever-increasing test data volume and excessive test power are two of the main concerns of VLSI testing. The “don’t-care” bits (also known as X-bits) in given test cube can be exploited for test data compression and/or test power reduction, and these techniques may contradict to each other because the very same X-bits are likely to be used for different optimization objectives. This paper proposes a capture-power-aware test compression scheme that is able to keep capture-power under a safe limit with low test compression ratio loss. Experimental results on benchmark circuits validate the effectiveness of the proposed solution.  相似文献   
273.
Sloshing causes liquid to fluctuate, making accurate level readings difficult to obtain. In this paper, a measurement system has been described that can accurately determine fluid quantity in the presence of slosh. The measurement system uses a single-tube capacitive sensor to obtain instantaneous level of the fluid surface. A neural network based classification technique has been applied to predict the actual quantity of the fluid under sloshing conditions. Effects of temperature variations and contamination on the capacitive sensor have been discussed and it is proposed that these effects can also be eliminated with the proposed neural network based classification system. To examine the performance of the classification system, many field trials were carried out on a running vehicle at various tank volume levels that range from 5 L to 50 L. The paper also investigates the effectiveness of signal enhancement on the neural network based signal classification system. Signal enhancement is performed using selected signal smoothing functions such Moving Mean, Moving Median, and Wavelet filters. Results obtained from the investigation are compared with traditionally used statistical averaging methods, and it proved that the neural network based measurement system can produce highly accurate fluid quantity measurements in a dynamic environment. The approach demonstrated herein will enable a wide range of fluid quantity measurement applications in the fields of automotive, naval and aviation industries to produce accurate fluid level readings.  相似文献   
274.
The application of ‘soluble’ (colloidal) manganese(IV) for chemiluminescence detection is reviewed, focussing on papers published since the last comprehensive review of the subject in 2008. Advances in this reagent system include: the on-line formation of manganese(IV); new insight into the light-producing pathway and selectivity of the reagent; its application to assess total antioxidants in plant derived samples and oxidative stress in biological fluids and tissues; and the replacement of the formaldehyde enhancer with ethanol.  相似文献   
275.
In-tube solid-phase microextraction (in-tube SPME) coupled with high performance liquid chromatography (HPLC) or liquid chromatography coupled to mass spectrometry (LC-MS) successfully determines drugs or biomarkers in biological samples by direct sample injection or by simple sample treatment. This technique uses a capillary column as extraction device. Several capillaries (wall-coated open tubular, sorbent-packed, porous monolithic rods, or fiber-packed) with unique phases have been developed and evaluated, aiming to improve the efficiency and selectivity of the in-tube SPME-LC technique. This review describes new developments and applications occurred in recent years, and discusses future trends with emphasis on new extraction devices and current technology used for the synthesis of selective sorbents for bioanalysis, such as (i) polypyrrole, (ii) restricted-access materials, (iii) immunosorbents, (iv) molecular imprinting polymers, (v) monolithic polymers, and (vi) bi-functional materials.  相似文献   
276.
The gain flattening of Yb3+-doped fiber amplifier of 1053 nm band has been realized in experiment using three cascade 1 × 2 fused tapered fiber coupler. The gain flattening band is about 20 nm with less than 1 dB power fluctuation around 1053 nm, which is agree with our numerical stimulation results very well.  相似文献   
277.
According to the imaging principle and characteristic of LASIS (Large Aperture Static Interference Imaging Spectrometer), we discovered that the 3D (three dimensional) image sequences formed by different interference pattern frames, which were formed in the imaging process of LASIS Interference hyperspectral image, had much stronger correlation than the original interference hyperspectral image sequences, either in 2D (two dimensional) spatial domain or in the spectral domain. We put this characteristic into image compression and proposed an adaptive OPD (optical path difference) and dislocation prediction algorithm for interference hyperspectral image compression. Compared the new algorithm proposed in this paper with Dual-Direction Prediction [1] proposed in 2009, lots of experimental results showed that the prediction error entropy of the new algorithm was much smaller. In the prediction step of lifting wavelet transform, this characteristic would also reduce the entropy of coefficients in high frequency significantly, which would be more advantageous for quantification coding [2].  相似文献   
278.
The instrument forward model of the modified super-wide-Sagnac imaging interferometer based on liquid crystals on Silicon (MSASII-LCoS) is developed as an integrated code package with Matlab language to simulate the images of satellite observations. There are five sub-models in the forward model including radiation model of O(1S), orbit attitude, filter, interferometer and array detector. The principle of each sub-model is described separately and then the overall forward model equation is derived. The four simulation images are obtained. Based on the integrated signal level for the daytime observations, the apparent measurement error of wind is less than 3 m/s and the signal noise ratio (SNR) is greater than 194 with a binning of 2 × 25 pixels at the tangent height range of 70-190 km.  相似文献   
279.
Plasmid DNA (pDNA)-based vaccines offer more rapid avenues for development and production if compared to those of conventional virus-based vaccines. They do not rely on time- or labour-intensive cell culture processes and allow greater flexibility in shipping and storage. Stimulating antibodies and cell-mediated components of the immune system are considered as some of the major advantages associated with the use of pDNA vaccines. This review summarizes the current trends in the purification of pDNA vaccines for practical and analytical applications. Special attention is paid to chromatographic techniques aimed at reducing the steps of final purification, post primary isolation and intermediate recovery, in order to reduce the number of steps necessary to reach a purified end product from the crude plasmid.  相似文献   
280.
This review discusses advances in the field of high resolution scanning electrochemical microscopy (HR-SECM) and scanning ion conductance microscopy (SICM) to study living cells. Relevant references from the advent of this technique in the late 1980s to most recent contributions in 2012 are presented with special discussion on high resolution images. A clear progress especially within the last 5 years can be seen in the field of HR-SECM. Furthermore, we also concentrate on the intrinsic properties of SECM imaging techniques e.g. different modes of image acquisition, their advantages and disadvantages in imaging living cells and strategies for further enhancement of image resolution, etc. Some of the recent advances of SECM in nanoimaging have also been discussed which may have potential applications in high resolution imaging of cellular processes.  相似文献   
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