This paper presents an O(n(2))-time algorithm for constructing two edge-disjoint paths connecting two given pairs of vertices in a given tournament graph. It improves the time complexity of a previously known O(n(4))-...
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This paper presents an O(n(2))-time algorithm for constructing two edge-disjoint paths connecting two given pairs of vertices in a given tournament graph. It improves the time complexity of a previously known O(n(4))-time algorithm.
We describe the operational algorithm for the retrieval of stratospheric, tropospheric, and total column densities of nitrogen dioxide (NO2) from earthshine radiances measured by the Ozone Monitoring Instrument (OMI),...
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We describe the operational algorithm for the retrieval of stratospheric, tropospheric, and total column densities of nitrogen dioxide (NO2) from earthshine radiances measured by the Ozone Monitoring Instrument (OMI), aboard the EOS-Aura satellite. The algorithm uses the DOAS method for the retrieval of slant column NO2 densities. Air mass factors (AMFs) calculated from a stratospheric NO2 profile are used to make initial estimates of the vertical column density. Using data collected over a 24-h period, a smooth estimate of the global stratospheric field is constructed. Where the initial vertical column densities exceed the estimated stratospheric field, we infer the presence of tropospheric NO2, and recalculate the vertical column density (VCD) using an AMF calculated from an assumed tropospheric NO2 profile. The parameters that control the operational algorithm were selected with the aid of a set of data assembled from stratospheric and tropospheric chemical transport models. We apply the optimized algorithm to OMI data and present global maps of NO2 VCDs for the first time.
Here, a method to suppress drift in intensity-modulated sensors is presented that preserves the advantages of such sensors including simplicity and low-cost components. This method is illustrated using metal hydride-b...
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Here, a method to suppress drift in intensity-modulated sensors is presented that preserves the advantages of such sensors including simplicity and low-cost components. This method is illustrated using metal hydride-based optical hydrogen sensors that can reliably, accurately, and quickly sense hydrogen across a large concentration range. These sensors rely on a metal hydride-sensing material that reversibly absorbs hydrogen when a hydrogen concentration is present. In turn, this causes a change in the optical properties which can be probed to determine the hydrogen concentration. To do this, two major methods exist: intensity- and frequency-modulated sensors. While intensity-modulated sensors are typically simpler and cheaper to fabricate, they may suffer from drifting light sources and unstable alignments. Using the fact that exposure to hydrogen reduces (increases) the optical transmission (reflectivity) of a Ta-based sensing material for blue/green light while it increases (decreases) the transmission for (near) infrared (IR) light, it is possible to differentiate between a changing hydrogen concentration and a drifting light source: Whereas the signal of both wavelengths is positively correlated for a drifting light source, the signal is negatively correlated when the hydrogen concentration changes. Using this algorithm, the drift on the signal can be reduced by a factor of 5 for intensity-modulated sensors. In a more general perspective, the wealth of information in the wavelength-dependent optical response allows for more advanced approaches to improve the signal and accuracy of (optical) sensors.
The algorithm proposed in this article provides high accuracy and requires only double-precision arithmetic. The calculated value obtained by the algorithm is proved to be accurate to 0.785 . ulp as long as the result...
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The algorithm proposed in this article provides high accuracy and requires only double-precision arithmetic. The calculated value obtained by the algorithm is proved to be accurate to 0.785 . ulp as long as the result does not underflow. In the case of subnormal results the error does not exceed 0.875 . ulp. The testing results have also shown that the implementation of the proposed algorithm has reasonable computational time compared to other implementations.
We investigated the algorithm analysis of the bubble generation in a microfluidic device to study the effect of the surface tension and the flow rate on the microbubble size. For the analysis of the surface tension, f...
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We investigated the algorithm analysis of the bubble generation in a microfluidic device to study the effect of the surface tension and the flow rate on the microbubble size. For the analysis of the surface tension, five different solutions were used: 3.5% brine, mineral oil, 1% polyethylene glycol (PEG) 400, 1% tween 80, and 1% triton X-100. The various flow rates were also employed: 5 approximate to 15 mu L/min for the liquid and 100 approximate to 200 mL/min for the gas phase. The size of the bubble was measured via the algorithm analysis and the bubble defect was also detected by c chart. We observed that the microbubble size was affected by the flow rates of solution and the gas. Hence, we developed an equation to estimate the size through the flow rate ratio between the solution and gas phase, showing that the microbubble size could be controlled by the liquid properties or the flow rates. Therefore, this algorithm-based microfluidic device could be a powerful tool for generating gas micro-bubbles in a controlled manner.
We describe our proposed algorithm for statistical estimation of the error of the dual energy method due to the quantum nature of radiation as applied to an X-ray inspection system containing sandwich detectors. Its a...
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We describe our proposed algorithm for statistical estimation of the error of the dual energy method due to the quantum nature of radiation as applied to an X-ray inspection system containing sandwich detectors. Its action is demonstrated using a specific example. Recommendations are given for the further use of the algorithm, in particular, for optimizing the structural elements of radiation sandwich detectors.
This investigation describes the use of a differential evolution (DE) algorithm to optimize cryopreservation solution compositions and cooling rates for specific cell types. Jurkat cells (a lymphocyte model cell type)...
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This investigation describes the use of a differential evolution (DE) algorithm to optimize cryopreservation solution compositions and cooling rates for specific cell types. Jurkat cells (a lymphocyte model cell type) and mesenchymal stem cells (MSCs) were combined with non-DMSO solutions at concentrations dictated by a DE algorithm. The cells were then frozen in 96-well plates at DE algorithm-dictated cooling rates in the range 0.5-10 degrees C/min. The DE algorithm was iterated until convergence resulted in identification of an optimum solution composition and cooling rate, which occurred within six to nine generations (seven to 10 experiments) for both cell types. The optimal composition for cryopreserving Jurkat cells included 300 mM trehalose, 10% glycerol and 0.01% ectoine (TGE) at 10 degrees C/min. The optimal composition for cryopreserving MSCs included 300 mM ethylene glycol, 1 mM taurine and 1% ectoine (SEGA) at 1 degrees C/min. High-throughput concentration studies verified the optimum identified by the DE algorithm. Vial freezing experiments showed that experimental solutions of TGE at 10 degrees C/min resulted in significantly higher viability for Jurkat cells than DMSO at 1 degrees C/min, while experimental solutions of SEGA at 10 degrees C/min resulted in significantly higher recovery for MSCs than DMSO at 1 degrees C/min;these results were solution-and cell type-specific. Implementation of the DE algorithm permits optimization of multicomponent freezing solutions in a rational, accelerated fashion. This technique can be applied to optimize freezing conditions, which vary by cell type, with significantly fewer experiments than traditional methods. Copyright (C) 2016 John Wiley & Sons, Ltd.
An efficient algorithm is proposed for the buffer allocation in a continuous flow production line with unreliable machines. The problem is formulated as a non-linear programming with linear constraints, and the concep...
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An efficient algorithm is proposed for the buffer allocation in a continuous flow production line with unreliable machines. The problem is formulated as a non-linear programming with linear constraints, and the concept of pseudo gradient and gradient projection is employed in developing the algorithm. Numerical experiment shows that the algorithm yields quite good solutions to the large-sized problems with the generalized linear constraints. The robustness to the initial solution and the efficiency of the algorithm is also shown.
Acute detection and high-resolution imaging of microRNAs (miRNAs) in living cancer cells have attracted great attention in clinical diagnosis and therapy. However, current methods suffer from low detection sensitivity...
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Acute detection and high-resolution imaging of microRNAs (miRNAs) in living cancer cells have attracted great attention in clinical diagnosis and therapy. However, current methods suffer from low detection sensitivity or heavy dependence on expensive and sophisticated spectrometers. Herein, a novel algorithm-assisted system of detecting and imaging miRNAs in living cancer cells was developed via the disassembly of plasmonic core-satellite probes coupled with strand displacement amplification (SDA). The target miRNAs in the system could trigger the disassembly of plasmonic core-satellite probes, leading to the color change in the scattering light of the probes, which could be captured by dark-field microscopy (DFM). The concentration of the target miRNAs was obtained by analyzing the dark-field image based on the proposed algorithm with a detection limit of 2 pM for miRNA-21. Thus, the performance in terms of simplicity and sensitivity of the system compared with one of the conventional spectrophotometers was well presented, which could inspire more clinical applications of inexpensive, intelligent, and rapid screening of cancer cells. The application software based on the proposed algorithm running on the Android platform was also developed, demonstrating the potential of remote diagnosis.
Effective acquisition of transition probability matrix is directly related to Internetware reliability computation. The characteristics of Markov chain in Internetware are discussed and analyzed, the construction of M...
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Effective acquisition of transition probability matrix is directly related to Internetware reliability computation. The characteristics of Markov chain in Internetware are discussed and analyzed, the construction of Markov chain and the acquisition of transition probability of Internetware are studied, the Internetware model based on Markov chain is constructed. Quantitative calculation method of transition probability based on the smallest quadratic difference is presented by using the occupancy of component executing the transition as the sample statistics to calculate transition probability. The approximation algorithm for computing transition probability matrix based on the modified projection gradient is designed, and it effectively guarantees the transition law of Markov chain and the characteristics of transition probability matrix. The experiment proves that the presented method and the designed algorithm can effectively compute transition probability matrix with great value in Internetware reliability computation.
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