检索结果-内蒙古大学图书馆

Track parameter propagation through the application of a new adaptive Runge-Kutta-Nystrom method in the ATLAS experiment

引用

JOURNAL OF INSTRUMENTATION 2009年第4期4卷 P04001-P04001页

作者： Lund, E. Bugge, L. Gavrilenko, I. Strandlie, A. Univ Oslo N-0316 Oslo Norway CERN European Org Nucl Res CH-1211 Geneva 23 Switzerland PN Lebedev Phys Inst Moscow 117924 Russia Gjovik Univ Coll N-2802 Gjovik Norway

In this paper we study several fixed step and adaptive Runge-Kutta methods suitable for transporting track parameters through an inhomogeneous magnetic field. Moreover, we present a new adaptive Runge-Kutta-Nystrom method which estimates the local error of the extrapolation without introducing extra stages to the original Runge-Kutta-Nystrom method. Furthermore, these methods are compared for propagation accuracy and computing cost efficiency in the simultaneous track and error propagation (STEP) algorithm of the common ATLAS tracking software. The tests show the new adaptive Runge-Kutta-Nystrom method to be the most computing cost efficient.

关键词： Simulation methods and programs Pattern recognition cluster finding calibration and fitting methods data processing methods

来源：评论

学校读者我要写书评

暂无评论

Eliminating metal artifacts in dental computed tomography using an elaborate sinogram normalization interpolation method with CNR-based metal segmentation

引用

JOURNAL OF INSTRUMENTATION 2024年第11期19卷 C11003-C11003页

作者： Lim, Younghwan Park, Sungmin Jeon, Duhee Kim, Woosung Lee, Soohyun Cho, Hyosung Yonsei Univ Dept Radiat Convergence Engn Wonju South Korea

Metal artifact reduction (MAR) in dental cone-beam computed tomography (CBCT) is critical for improving its clinical usefulness and remains a challenging problem. This study presents an elaborate sinogram normalization interpolation (SNI) method with contrast-to-noise ratio (CNR)-based metal segmentation to eliminate metal artifacts in dental CBCT. The proposed MAR method involves three main steps: (1) CNR-based segmentation of a metal trace in the sinogram domain;(2) generation of a residual artifact-reduced prior sinogram;and (3) sinogram completion using the prior sinogram, followed by filtered-backprojection (FBP)-based CBCT reconstruction and metal insertion processes. To verify the efficacy of the proposed method, simulations and experiments were performed using numerical and physical dental phantoms with several metal inserts. The quality of the resulting CBCT images was quantitatively evaluated using the structural similarity (SSIM) metric and compared to those obtained with other interpolation-based MAR methods. A tabletop setup for the micro-CT system was used in the experiment, which comprised an X-ray tube operated under tube conditions of 70 kV(p) and 5 mA and a flat-panel detector with a pixel size of 198 mu m. Our results indicate that the CNR-based metal segmentation method precisely identified traces of metallic objects on the sinogram, and thereby, the proposed SNI-based MAR method considerably reduced metal artifacts in dental CBCT images without introducing any contrast anomalies. The SSIM values of the CBCT images obtained with the proposed MAR method were 0.99 and 0.95 for the simulation and experiment, respectively, which are approximately 11% and 9% greater than those with a simple threshold-based linear interpolation method, respectively, improving the image quality. The proposed MAR method can be applied to reduce metal artifacts in real-world dental CBCT systems.

关键词： data processing methods Image reconstruction in medical imaging data reduction methods Image filtering

来源：评论

学校读者我要写书评

暂无评论

Neutron radiography as a non-destructive method for diagnosing neutron converters for advanced thermal neutron detectors

引用

JOURNAL OF INSTRUMENTATION 2016年第3期11卷 C03033-C03033页

作者： Muraro, A. Albani, G. Cippo, E. Perelli Croci, G. Angella, G. Birch, J. Cazzaniga, C. Caniello, R. Dell'Era, F. Ghezzi, F. Grosso, G. Hall-Wilton, R. Hoglund, C. Hultman, L. Schimdt, S. Robinson, L. Rebai, M. Salvato, G. Tresoldi, D. Vasi, C. Tardocchi, M. IFP CNR Ist Fis Plasma P Caldirola Via Cozzi 53 Milan Italy Univ Milano Bicocca Dipartimento Fis Piazza Sci 3 Milan Italy IENI CNR Via Cozzi 53 Milan Italy Linkoping Univ Dept Phys Chem & Biol IFM Thin Film Phys Div SE-58183 Linkoping Sweden STFC Rutherford Appleton Lab ISIS Didcot Oxon England European Spallat Source ESS ERIC Tunavagen 24 S-22363 Lund Sweden IPCF CNR Ist Proc Chim Fis Viale Ferdinando Stagno dAlcontres 37 Messina Italy

Due to the well-known problem of He-3 shortage, a series of different thermal neutron detectors alternative to helium tubes are being developed, with the goal to find valid candidates for detection systems for the future spallation neutron sources such as the European Spallation Source (ESS). A possible He-3-free detector candidate is a charged particle detector equipped with a three dimensional neutron converter cathode (3D-C). The 3D-C currently under development is composed by a series of alumina (Al2O3) lamellas coated by 1 mu m of B-10 enriched boron carbide (B4C). In order to obtain a good characterization in terms of detector efficiency and uniformity it is crucial to know the thickness, the uniformity and the atomic composition of the B4C neutron converter coating. In this work a non-destructive technique for the characterization of the lamellas that will compose the 3D-C was performed using neutron radiography. The results of these measurements show that the lamellas that will be used have coating uniformity suitable for detector applications. This technique (compared with SEM, EDX, ERDA, XPS) has the advantage of being global (i.e. non point-like) and non-destructive, thus it is suitable as a check method for mass production of the 3D-C elements.

关键词： Inspection with neutrons Neutron radiography Image filtering data processing methods

来源：评论

学校读者我要写书评

暂无评论

Equilibration correction of temporal measurements for sudden ²²²Rn concentration changes

引用

JOURNAL OF INSTRUMENTATION 2016年第2期11卷 T02002-T02002页

作者： Tan, Y. Tokonami, S. Liu, H. Kearfott, K. J. Hengyang Normal Univ Coll Phys & Elect Engn Hengyang 421008 Peoples R China Hirosaki Univ Inst Radiat Emergency Med Dept Radiat Phys Hirosaki Aomori 0368564 Japan Hengyang Normal Univ Coll Comp Sci & Technol Hengyang 421008 Peoples R China Univ Michigan Dept Nucl Engn & Radiol Sci Ann Arbor MI 48109 USA

Rn-222 and Rn-220 can be used as tracers of groundwater or submarine springs, and Rn-222 in water also could indicate indoor radon problems in some regions. The half-life of Rn-222 is long enough that its concentration may remain significant during transit over relatively long distances, while that of Rn-220 is not. Prior research revealed that it took about 15 min for the radon to achieve gas equilibrium at a water flow rate of 17.5 L min(-1), which is approximately equivalent to the time required for the Rn-222-Po-218 pair to approach radioactive equilibrium and is limiting in terms of measurements of sudden radon concentration change. In this work, an algorithm is applied to improve the continuous tracing of radon concentrations in the field environment. Results of a laboratory experiment analyzed applying the analysis method illustrated its ability to allow immediate identification of sharp concentration increases. In this paper we find that a precipitous drop in radon concentrations lead to improper corrected values as the result of measurement uncertainties prior to the drop, and a method using zero instead negative values for reducing the uncertainties under such condition also is proposed.

关键词： data processing methods Models and simulations Spectrometers Simulation methods and programs

来源：评论

学校读者我要写书评

暂无评论

Robustness of planar Fourier capture arrays to colour changes and lost pixels

引用

JOURNAL OF INSTRUMENTATION 2012年第1期7卷 C01061-C01061页

作者： Gill, P. R. Lee, C. Sivaramakrishnan, S. Molnar, A. Cornell Univ Sch Elect & Comp Engn Ithaca NY 14853 USA Univ Toronto Dept Psychol Toronto ON M5S 3G3 Canada

Planar Fourier capture arrays (PFCAs) are optical sensors built entirely in standard microchip manufacturing flows. PFCAs are composed of ensembles of angle sensitive pixels (ASPs) that each report a single coefficient of the Fourier transform of the far-away scene. Here we characterize the performance of PFCAs under the following three non-optimal conditions. First, we show that PFCAs can operate while sensing light of a wavelength other than the design point. Second, if only a randomly-selected subset of 10% of the ASPs are functional, we can nonetheless reconstruct the entire far-away scene using compressed sensing. Third, if the wavelength of the imaged light is unknown, it can be inferred by demanding self-consistency of the outputs.

关键词： Image filtering data processing methods Analysis and statistical methods

来源：评论

学校读者我要写书评

暂无评论

Study on deconvolution of alpha-particle spectra using metaheuristic optimization and multivariate analysis

引用

JOURNAL OF INSTRUMENTATION 2024年第1期19卷 P01016页

作者： Li, Xuebin Pan, Lantian Yang, Luchun Jin, Zhao Wuhan 2nd Ship Design & Res Inst Wuhan 430205 Hubei Peoples R China

To find a global optimal solution and obtain further insight into the parameters of the peak shape fitting function, metaheuristic optimization algorithms, and multivariate analysis techniques are employed to study the deconvolution of alpha -particle spectra. An improved peak shape model composed of the Bortels-Collaers function and Levy distribution function, which aims to handle the high-energy tailing, is proposed. A newly developed metaheuristic optimization method, Bonobo Optimizer (BO) is adopted to seek optimal parameters in the peak shape function. Multivariate analysis (MVA) techniques are used to find hidden information in the shape model. Pearson's correlation tells the mutual variation relationship among parameters, while Multidimensional scaling (MDS) shows similarities of parameters through a 2D plot. Effects of parameters upon the regression accuracy are obtained via the Student t -test. Self -organizing Mapping (SOM) is utilized to mine intrinsic relations among these parameters through visual images. AM243-1 test alpha spectra example is selected to examine the proposed methodology. The improved model is more accurate when handling the high-energy tailing features. Compared with traditional gradient -based optimization algorithms, BO can find global solutions without tedious work in initial solution setting and constraint handling. More information is mined through MVA and further understanding of the peak shape function is obtained.

关键词： Pattern recognition cluster finding calibration and fitting methods data processing methods Interaction of radiation with matter

来源：评论

学校读者我要写书评

暂无评论

A hardware implementation of Region-of-Interest selection in LAr-TPC for data reduction and triggering

引用

JOURNAL OF INSTRUMENTATION 2010年第12期5卷 P12006-P12006页

作者： Baibussinov, B. Centro, S. Cieslik, K. Dequal, D. Farnese, C. Fava, A. Gibin, D. Guglielmi, A. Meng, G. Pietropaolo, F. Rubbia, C. Scantamburlo, E. Varanini, F. Ventura, S. Ist Nazl Fis Nucl Sez Padova I-35131 Padua Italy Univ Padua Dipartimento Fis I-35121 Padua Italy Ist Nazl Fis Nucl Lab Nazl Gran Sasso I-67010 Assergi AQ Italy CERN European Lab Particle Phys CH-1211 Geneva 23 Switzerland

Large Liquid Argon TPC detectors in the range of multi-kton mass for neutrino and astroparticle physics require the extraction and treatment of signals from some 10(5) wires. In order to increase the throughput of the DAQ system an on-line lossless data compression has been realized reducing by almost a factor 4 the data flow. Moreover a new efficient on-line identification algorithm of wire hits was studied, implemented on the ICARUS digital read-out boards and fully tested on the ICARINO LAr-TPC facility operated at LNL INFN Laboratory with cosmic-rays. This system permits the extraction of the event Region-of-Interest maximizing the global throughput of the DAQ and the realization of a trigger based on charge deposition on the wires. Capability to trigger isolated low energy events down to few MeV visible energy was also demonstrated.

关键词： data processing methods Trigger concepts and systems (hardware and software) data reduction methods Time projection chambers

来源：评论

学校读者我要写书评

暂无评论

methods of signal processing and cosmic muon calibration for the BM@N sampling lead/scintillator hadron calorimeter

引用

JOURNAL OF INSTRUMENTATION 2020年第5期15卷

作者： Morozov, S. Finogeev, D. Golubeva, M. Guber, F. Ivashkin, A. Izvestnyy, A. Kapishin, M. Karpushkin, N. Petukhov, O. Inst Nucl Res RAS Prospekt 60 Letiya Oktyabrya 7a Moscow Russia Moscow Inst Phys & Technol Inst Sky Per 9 Dolgoprudnyi Moscow Region Russia Natl Res Nucl Univ MEPhI Kashirskoe Sh 31 Moscow Russia Joint Inst Nucl Res Dubna Russia

Recently developed new forward lead/scintillator sampling hadron calorimeters with transverse and longitudinal segmentation will be used in the upgraded BM@N (Baryonic Matter at Nuclotron) experiment at the Nuclotron-NICA acceleration complex in JINR (Dubna). These calorimeters are very important for measurements of centrality and the reaction plane orientation in heavy-ion collisions. Digitizing the analog signals in a wide dynamic range with sampling ADC leads to the fluctuations of the measured charge. The procedure of signal processing based on the Prony least squares fit method has been developed to improve the response requiring minimum machine time. In addition, fitting the signals with a known function allows one to select effectively weak signals at the level of electronics noise, that is important for performing a calibration of calorimeter sections with cosmic muons for the BM@N experiment. The same procedure will be used for hadron calorimeter in CBM experiment at FAIR. New methods of signal processing and cosmic muon tracking for forward hadron calorimeters will be presented.

关键词： Calorimeters data processing methods Front-end electronics for detector readout

来源：评论

学校读者我要写书评

暂无评论

Bayesian Neural Network Variational Autoencoder Inverse Mapper (BNN-VAIM) and its application in Compton Form Factors extraction

引用

JOURNAL OF INSTRUMENTATION 2024年第8期19卷 C08003页

作者： Bin Hossen, Fayaz Alghamdi, Tareq Almaeen, Manal Li, Yaohang Old Dominion Univ Norfolk VA 23529 USA Al Baha Univ Al Baha 65779 Saudi Arabia Jouf Univ Sakaka 72341 Aljouf Saudi Arabia

We extend the Variational Autoencoder Inverse Mapper (VAIM) framework for the inverse problem of extracting Compton Form Factors (CFFs) from deeply virtual exclusive reactions, such as the unpolarized Deeply virtual exclusive scattering (DVCS) cross section. VAIM is an end-to-end deep learning framework to address the solution ambiguity issue in ill-posed inverse problems, which comprises of a forward mapper and a backward mapper to simulate the forward and inverse processes, respectively. In particular, we incorporate Bayesian Neural Network (BNN) into the VAIM architecture (BNN-VAIM) for uncertainty quantification. By sampling the weights and biases distributions of the BNN in the backward mapper of the VAIM, BNN-VAIM is able to estimate prediction uncertainty associated with each individual solution obtained for an ill-posed inverse problem. We first demonstrate the uncertainty quantification capability of BNN-VAIM in a toy inverse problem. Then, we apply BNN-VAIM to the inverse problem of extracting 8 CFFs from the unpolarized DVCS cross section.

关键词： Analysis and statistical methods data processing methods

来源：评论

学校读者我要写书评

暂无评论

Waveform resampling with LMN method

引用

JOURNAL OF INSTRUMENTATION 2024年第10期19卷 P10029页

作者： Gerlach, L. Gu, W. Nayak, N. Qian, X. Viren, B. Brookhaven Natl Lab Upton NY 11973 USA Princeton Univ Princeton NJ 08544 USA

Resampling is a common technique applied in digital signal processing. Based on the Fourier Transformation (FFT), we apply an optimization called here the LMN method to achieve and robust re-sampling. In addition to performance comparisons with some other popular methods, we illustrate the effectiveness of this LMN method in a particle physics experiment: re-sampling of waveforms from Liquid Argon Time Projection Chambers.

关键词： data processing methods Digital signal processing (DSP) Neutrino detectors Time projection Chambers (TPC)

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：