Automatic spectrum recognition system for charge state analysis in electron cyclotron resonance ion sources

The Electron Cyclotron Resonance(ECR)ion source is a critical device for producing highly charged ion beams in various applications.Analyzing the charge-state distribution of the ion beams is essential,but the manual analysis is labor-intensive and prone to inaccuracies due to impurity ions.An automatic spectrum recognition system based on intelligent algorithms was proposed for rapid and accurate chargestate analysis of ECR ion sources.The system employs an adaptive window-length Savitzky-Golay(SG)filtering algorithm,an improved automatic multiscale peak detection(AMPD)algorithm,and a greedy matching algorithm based on the relative distance to accurately match different peaks in the spectra with the corresponding charge-state ion species.Additionally,a user-friendly operator interface was developed for ease of use.Extensive testing on the online ECR ion source platform demonstrates that the system achieves high accuracy,with an average root mean square error of less than 0.1 A for identifying charge-state spectra of ECR ion sources.Moreover,the system minimizes the stand-ard deviation of the first-order derivative of the smoothed signal to 81.1846 A.These results indicate the capability of the designed system to identify ion beam spectra with mass numbers less than Xe,including Xe itself.The proposed automatic spectrum recognition system represents a significant advancement in ECR ion source analysis,offering a rapid and accurate approach for charge-state analysis while enhancing supply efficiency.The exceptional performance and successful imple-mentation of the proposed system on multiple ECR ion source platforms at IMPCAS highlight its potential for widespread adoption in ECR ion source research and applications.

Matched Filter Based Spectrum Sensing When Primary User Has Multiple Power Levels

In this paper,we investigate the matched filter based spectrum sensing in a more reasonable cognitive radio(CR) scenario when the primary user(PU) has more than one transmit power levels,as regulated in most standards,i.e.,IEEE 802.11 Series,GSM,LTE,LTE-A,etc.This new multiple primary transmit power(MPTP) scenario is specialized by two different targets:detecting the presence of PU and identifying the power level.Compared to the traditional binary sensing where only the presence of PU is checked,SU may attain more information about the primary network(making CR more "intelligent") and design the subsequent optimization strategy.The key technology is the multiple hypothesis testing as opposed to the traditional binary hypothesis testing.We discuss two situations under whether the channel phase is known or not,and we derive the closed form solutions for decision regions and several performance metrics,from which some interesting phenomenons are observed and the related discussions are presented.Numerical examples are provided to corroborate the proposed studies.

Recognition of the Projective Special Linear Group over GF(3)

Let P be a finite group and denote by w（P） the set of its element orders. P is called k-recognizable by the set of its element orders if for any finte group G with ω（G） =ω（P） there are, up to isomorphism, k finite groups G such that G ≌P. In this paper we will prove that the group Lp（3）, where p 〉 3 is a prime number, is at most 2-recognizable.

A Fiber Tractography Study of Social-Emotional Related Fiber Tracts in Children and Adolescents with Autism Spectrum Disorder

The symptoms of autism spectrum disorder（ASD） have been hypothesized to be caused by changes in brain connectivity. From the clinical perspective, the‘‘disconnectivity＇＇ hypothesis has been used to explain characteristic impairments in ‘‘socio-emotional＇＇ function.Therefore, in this study we compared the facial emotional recognition（FER） feature and the integrity of socialemotional-related white-matter tracts between children and adolescents with high-functioning ASD（HFA） and their typically developing（TD） counterparts. The correlation between the two factors was explored to find out if impairment of the white-matter tracts is the neural basis of social-emotional disorders. Compared with the TD group,FER was significantly impaired and the fractional anisotropy value of the right cingulate fasciculus was increased in the HFA group（P ／ 0.01）. In conclusion, the FER function of children and adolescents with HFA was impaired and the microstructure of the cingulate fasciculus had abnormalities.

Finite Groups Isospectral to Simple Groups

The spectrum of a finite group is the set of element orders of this group.The main goal of this paper is to survey results concerning recognition of finite simple groups by spectrum,in particular,to list all finite simple groups for which the recognition problem is solved.