Simulation of switchers for CNOT-gates based on optical waveguide interaction with coupled mode theory

The paper is devoted to simulation of interactions in the system of two symmetrical slab optical waveguides, that guide exactly two guided modes with the aim to use the directional coupler as a switcher for CNOT gate in the waveguide model of quantum-like computations. The coupling mode theory is used to solve the system of Maxwell equations. The asymptotic analysis is applied to simplify the system of differential equations, so an approximate analytic solution can be found. The solution obtained is used for the quick directional coupler parameters adjusting algorithm, so the power exchange in the system occurs as that of correctly working CNOT-gate switcher. Moreover, the finite difference method is used to solve the stricter system of equations, that additionally takes into account the process of power exchange between different order guided modes, so the computational error of the device can be estimated. It was obtained, that the possible size of the device may not exceed 1 mm in the largest dimension, while the computational error does not exceed 3%.

Computer Simulations of Dynamic Response of Ferrofluids on an Alternating Magnetic Field with High Amplitude

The response of ferrofluids to a high-amplitude AC magnetic field is important for several applications including magnetic hyperthermia and biodetection. In computer simulations of the dynamic susceptibility of a ferrofluid outside the linear response region, there are several problems associated with the fact that an increase in the frequency of the AC field leads to the appearance of additional computational errors, which can even lead to unphysical results. In this article, we study the dependence of the computational error arising in the computer simulation of the dynamic susceptibility on the input parameters of the numerical algorithm: the length of the time step, the total number of computer simulation periods, and averaging period. Computer simulation is carried out using the Langevin dynamics method and takes Brownian rotational relaxation of magnetic particles and interparticle interactions into account. The reference theory [Yoshida T.; Enpuku K. Jap. J. Ap. Phys. 2009] is used to estimate computational error. As a result, we give practical recommendations for choosing the optimal input parameters of the numerical algorithm, which make it possible to obtain reliable results of the dynamic susceptibility of a ferrofluid in a high-amplitude AC field in a wide frequency range.

Evaluation of cell segmentation methods without reference segmentations

Cell segmentation is a cornerstone of many bioimage informatics studies. Inaccurate segmentation introduces computational error in downstream cellular analysis. Evaluating the segmentation results is thus a necessary step for developing the segmentation methods as well as choosing the most appropriate one for a certain kind of tissue or image. The evaluation process has typically involved comparison of segmentations to those generated by humans, which can be expensive and subject to unknown bias. We present here an approach that seeks to evaluate cell segmentation methods without relying upon comparison to results from humans. For this, we defined a number of segmentation quality metrics that can be applied to multichannel fluorescence images. We calculated these metrics for 11 previously-described segmentation methods applied to datasets from 5 multiplexed microscope modalities covering 5 tissues. Using principal component analysis to combine the metrics we defined an overall cell segmentation quality score and ranked the segmentation methods. A Reproducible Research Archive containing all data and code will be made available upon publication at http://hubmap.scs.cmu.edu.

A High-Speed and Power-Efficient Approximate Adder for Image Processing Applications

Most image processing applications are naturally imprecise and can tolerate computational error up to a specific limit. In such applications, savings in power are achieved by pruning the data path units, such as an adder module. Truncation, however, may lead to errors in computing, and therefore, it is always a challenge between the amount of error that can be tolerated in an application and savings achieved in area, power and delay. This paper proposes a segmented approximate adder to reduce the computation complexity in error-resilient image processing applications. The sub-carry generator aids in achieving a faster design while carry speculation method employed improves the accuracy. Synthesis results indicate a reduced die-area up to 36.6%, improvement in delay up to 62.9%, and reduction in power consumption up to 34.1% compared to similar work published previously. Finally, the proposed adder is evaluated by using image smoothing and sharpening techniques. Simulations carried out on these applications prove that the proposed adder obtains better peak signal-to-noise ratio than those available in the literature.

A fuzzy DEMATEL approach for evaluating the risk factors (Case study: The instruction center of Iran’s national oil company)

Many risk factors are dependent on each other and taking this into account can help manage appropriate decisions. The poor evaluation of these factors will impose high costs in many real applications, especially for a supply chain. There are different methods for risk evaluating and their effects for ranking them. For instant, in the fuzzy DEMATEL method, the experts’ linguistic opinions and preferences on the agent effects are used as the input. The important point is how these opinions are aggregated to produce the less computational error. In this regard, this paper proposes a new method based on statistical inferences for a fuzzy DEMATEL approach for evaluating the factors of a supply chain. This method was applied to a case study and the results showed that the proposed method was better than other methods for integrating the experts’ opinions in a supply chain. However, this method was proposed for the evaluation of supply chain factors, it can be applied to other systems as well.

Free Vibration and Frequency Calculation in Tall Buildings with Stepped Tube-in-Tube Systems

This study investigates the free vibration and frequency analysis of tall buildings with stepped cross-sections for stepped tube-in-tube structures. Dynamic equations were presented in accordance with the stepped structural system for free vibration and the differential equations were solved according to the application of boundary conditions and flexural and shear stiffness and stepped cross-section of different steps. The answer was converted to an 8x8 matrix and was obtained using the determinants of matrix and mathematical calculations of frequency. Nine mathematical computational models were designed for stepped tube-in-tube structures for a 50-story tube-in-tube building by increasing the height of the outer tube by 15 meters. Finally, the heights of the inner and outer tubes were equalized by increasing the height of the outer tube and then compared with the results of free vibration in the articles with the tube-in-tube structural system with equal height and characteristics. Using this method, the frequency of structures was calculated correctly and the obtained results from finite element analysis showed that this mathematical method accurately calculated the frequency. It was found that this method was accurate enough and the obtained computational error was very small. The results showed that the frequency decreases by adding to the outer tube and increasing its height.

Nanopore sequencing reveals TACC2 locus complexity and diversity of isoforms transcribed from an intronic promoter

Gene expression is controlled at the transcriptional and post-transcriptional levels. The TACC2 gene was known to be associated with tumors but the control of its expression is unclear. We have reported that activity of the intronic promoter p10 of TACC2 in primary lesion of endometrial cancer is indicative of lymph node metastasis among a low-risk patient group. Here, we analyze the intronic promoter derived isoforms in JHUEM-1 endometrial cancer cells, and primary tissues of endometrial cancers and normal endometrium. Full-length cDNA amplicons are produced by long-range PCR and subjected to nanopore sequencing followed by computational error correction. We identify 16 stable, 4 variable, and 9 rare exons including 3 novel exons validated independently. All variable and rare exons reside N-terminally of the TACC domain and contribute to isoform variety. We found 240 isoforms as high-confidence, supported by more than 20 reads. The large number of isoforms produced from one minor promoter indicates the post-transcriptional complexity coupled with transcription at the TACC2 locus in cancer and normal cells.

Stability Analysis of Irregular Cavities in Tunnel Using Geomagic-COMSOL Coupling Method

The erosion of soluble rock and transformation of groundwater result in the high irregularity of cavities in tunnel. At present, however, karst cavities are mainly simplified as circular, rectangular, or elliptical shape in the numerical simulation. The purpose of this paper is to propose a new method to analyze the stability of irregular cavities. First of all, we used the drilling laser scanning method to reconstruct the three-dimensional point clouds model of irregular cavities. Furthermore, we proposed the method of determining the point density to reduce the computational error under the premise of ensuring the accuracy in engineering scale. We also developed the Geomagic-COMSOL coupling numerical method to conduct the stability analysis of irregular cavities. The results demonstrated that the geometrical shape of karst cavities has great effects on the deformation and mechanical properties of the surrounding rock. The displacement and equivalent plastic strain of simplified cavities exhibited symmetric characteristics, while those of irregular cavities are highly randomly distributed. We noted that a greater displacement value and more intensive plastic strain can be triggered by irregular cavities shape, compared with the simplified cavity shape. The results also showed that the larger displacement occurred at the long-edge part, while the plastic zone was concentrated at the sharp turning angle of the irregular cavities.

Conformational energies and equilibria of cyclic dinucleotides in vacuo and in solution: computational chemistry vs. NMR experiments

Computational “error bars” for modelling cyclic dinucleotides – NMR experiment vs. quantum mechanics and molecular dynamics.