Research on Spectrum Feature Identification of Indoor Multimodal Communication Signal

In order to solve the problem of large signal acquisition error caused by radio wave multipath effect in indoor environment, firstly, the signal source carried on the motion platform is collected for spectrum signal, and the signal processed by wavelet threshold denoising algorithms extracted and stored for spectrum feature extraction. Then, after data training and identification, the signal source is input into the system in random mode for identification. The experimental results show that the improved fuzzy clustering algorithm (FCA) is 12.7% higher than the spectrum envelope extraction method (SEEM) in the recognition rate of spectrum characteristics of different modes of signal source.

Moduli stabilisation and the statistics of axion physics in the landscape

String theory realisations of the QCD axion are often said to belong to the anthropic window where the decay constant is around the GUT scale and the initial misalignment angle has to be tuned close to zero. In this paper we revisit this statement by studying the statistics of axion physics in the string landscape. We take moduli stabilisation properly into account since the stabilisation of the saxions is crucial to determine the physical properties of the corresponding axionic partners. We focus on the model-independent case of closed string axions in type IIB flux compactifications and find that their decay constants and mass spectrum feature a logarithmic, instead of a power-law, distribution. In the regime where the effective field theory is under control, most of these closed string axions are ultra-light axion-like particles, while axions associated to blow-up modes can naturally play the role of the QCD axion. Hence, the number of type IIB flux vacua with a closed string QCD axion with an intermediate scale decay constant and a natural value of the misalignment angle is only logarithmically suppressed. In a recent paper we found that this correlates also with a logarithmic distribution of the supersymmetry breaking scale, providing the intriguing indication that most, if not all, of the phenomenologically interesting quantities in the string landscape might feature a logarithmic distribution.

A novel approach to radiographic detection of bucco-palatal/lingual dilacerations: A preliminary study with ImageJ

The purpose of our study is to determine whether bucco-palatal/lingual (BPL) root dilacerations (RD), especially in single root teeth, can be determined using the ImageJ program through only one periapical radiography. Extracted teeth without any RD ( n = 8) were determined as the control group (Group 1) and with RD in apical 1/3 part at least 20° with the longitudinal axis in the BPL direction ( n = 8) as the study group (Group 2). With the help of a simple holder system prepared, digital periapical radiographs of all teeth were taken in an anteroposterior position. Histogram analysis of all periapical radiographs was performed using the spectrum feature of ImageJ software. It was aimed to make a dilaceration analysis by comparing the groups using mean, standard deviation, minimum, maximum, and bin width values. As a result of the Mann-Whitney U test, all mean and maximum values showed a statistically significant difference between the study and control groups ( p < 0.05). This pilot study revealed that the ImageJ software can be used to diagnose BPL dilaceration in the apical 1/3 part of the root. It is important for dentists and patients that it can contribute to limiting the radiation dose to which patients will be exposed.

A New Recongnition System Based on Gabor Wavelet Transform for Shockable Electrocardiograms

This paper presents a new recognition system for shockable arrhythmias for patients suffering from sudden cardiac arrest. In order to develop the recognition system, lots of electrocardiogram (ECGs) have been analyzed by using gabor wavelet transform (GWT). Although, there is a huge number of spectrum feature parameters, recognition performance for all combinations for spectrum feature parameters are evaluated, and on the basis of the evaluation results, useful and effective spectrum features for ECGs are extracted. As a result, the proposed recognition system based on the selected effective spectrum feature parameters can achieved good performance comparing with the existing results.