A belief function classifier based on information provided by noisy and dependent features

A model and method are proposed for dealing with noisy and dependent features in classification problems. The knowledge base consists of uncertain logical rules forming a probabilistic argumentation system. Assumption-based reasoning is the inference mechanism that is used to derive information about the correct class of the object. Given a hypothesis regarding the correct class, the system provides a symbolic expression of the arguments for that hypothesis as a logical disjunctive normal form. These arguments turn into degrees of support for the hypothesis when numerical weights are assigned to them, thereby creating a support function on the set of possible classes. Since a support function is a belief function, the pignistic transformation is then applied to the support function and the object is placed into the class with maximal pignistic probability.     

X‐ray analog pixel array detector for single synchrotron bunch time‐resolved imaging

Dynamic X‐ray studies can reach temporal resolutions limited by only the X‐ray pulse duration if the detector is fast enough to segregate synchrotron pulses. An analog integrating pixel array detector with in‐pixel storage and temporal resolution of around 150 ns, sufficient to isolate pulses, is presented. Analog integration minimizes count‐rate limitations and in‐pixel storage captures successive pulses. Fundamental tests of noise and linearity as well as high‐speed laser measurements are shown. The detector resolved individual bunch trains at the Cornell High Energy Synchrotron Source at levels of up to 3.7 × 10³ X‐rays per pixel per train. When applied to turn‐by‐turn X‐ray beam characterization, single‐shot intensity measurements were made with a repeatability of 0.4% and horizontal oscillations of the positron cloud were detected.     

Elastic anomalies of La0.67Sr0.33−xBaxMnO3 in the vicinity of TC

With a view to understand the elastic behaviour of a material system, La_0.67Sr_0.33−xBa_xMnO₃ (where x=0, 0.1, 0.2, and 0.33) especially in the vicinity of their magnetic transition temperature T_C, a systematic investigation of ultrasonic velocity over a temperature range 300-400 K has been carried out. The materials prepared by citrate gel route, were characterized structurally by XRD and on analyzing the XRD patterns, it has been concluded that all the samples are having rhombohedral structure with space group of R3?c. The magnetic (T_C) transition temperatures determined by AC susceptibility measurements are found to decrease continuously with increasing barium concentration. Finally, the ultrasonic longitudinal velocities of all the samples are found to exhibit considerable softening in the vicinity of their magnetic transition temperatures, T_C and the observed behaviour is explained using mean field theory and Jahn-Teller theorem.     

用于频域方法测量超短电子束纵向分布的Kramers-Kronig变换研究

Kramers-Kronig（K-K）变换方法被广泛地应用于频域测量中还原超短电子束团分布,成为分析电子束团形状、长度等参量的有效工具.研究发现,利用该方法分析电子束参量时,自相干曲线基底的选择、低频损耗与高频截止及插值外推位置的选择,对束团参量有重要的影响.以清华大学加速器实验平台采用相干渡越辐射测试束团长度为例,分析了上述参量的选取对测量结果的影响,讨论了选择K-K变换的关键物理参量的方法.     

Synthesis and Infrared Spectra Computation of Sterically Congested 2,2-Disubstituted Indane-1,3-dione Derivatives

Sterically congested 2,2-disubstituted indane-1,3-dione derivatives have been syn-thesized and characterized by 1H NMR,13C NMR,FT-IR and elemental analysis.The B3LYP/HF calculations for computation of IR spectra have been carried out for the title compounds at the 6-31G and 6-311++G basis set levels.Predicted vibrational frequencies have been assigned and compared with the experimental FT-IR spectra and they are supported each other.     

Synthesis and Infrared Spectra Computation of Sterically Congested 2,2-Disubstituted Indane-113-dione Derivatives

Sterucally congested 2,2-disubstituted indane-1,3-dione derivatives have been syn- thesized and characterized by <'1>H NMR, <'13>C NMR, FT-IR and elemental analysis.The B3LYP/HF calculations for computation of IR spectra have been carried out for the title compounds at the 6- 31G* and 6-311-m-G** basis set levels.Predicted vibrational frequencies have been assigned and compared with the experimental FT-IR spectra and they are supported each other.     

Heterobimetallic Mn(II)-Hg(II) polynuclear complexes containing Hg(SCN)4 unit - Synthesis, spectroscopic investigations, X-ray studies and magnetic properties

Two novel heterobimetallic coordination polymers with Hg(SCN)₄²⁻ as a linker have been synthesized and characterised by means of IR, EPR, magnetic measurements and single crystal X-ray. The compounds [Mn(bpzm)Hg(SCN)₄]_n (1) and [Mn(bdmpzm)₂Hg(SCN)₄]_n (2) form supramolecular framework structures. The compound 1 creates a three-dimensional coordination polymer and compound 2 has one-dimensional chain structure extending along the crystallographic direction [1 0 0]. Variable-temperature magnetic susceptibility measurements show very weak antiferromagnetic interactions between the paramagnetic Mn(II) centres of structures 1 and 2.     

Design and development of pyrolyser to extract medicinal oil from the stem of Ziziphus jujuba

Pyrolysis as an extraction method of phytochemicals from plant parts for medicinal applications is less explored. Practitioners of traditional Indian medicine use a process which is a crude equivalent of pyrolysis, to extract oily substances from stem parts of plants and use them in treatment of various ailments. In this study, a prototype pyrolyser is fabricated to simulate the traditional method and the stem part of Ziziphus jujuba is subjected to pyrolysis using the pyrolyser under controlled conditions. Based on the principle of applied pyrolysis, the engineering design is conceptualized and drawing for a prototype extractor is made. Material selection for the main reactor vessel and the heating system with controller is finalized. The prototype is fabricated. The oily extract obtained is compared with the extract from the traditional method for compositional identity and phyto chemistry to validate the process. The chemical similarities of the extracts from both methods establishes pyrolsis as the basic principle behind the traditional method and this validates the design of the pyrolyser. The FTIR and GC-MS analysis of the extracted oily substance from both methods reveals the presence of various cyclic, nitrogenous, long chain and heterocyclic compounds which are believed to be the pyrolysates of various cyclopeptide alkaloids reportedly present in the stem of Ziziphus jujuba. These phytochemicals have sedative property and are likely to be responsible for the curative nature of the oil used in the treatment of various human disorders and the research substantiates the stem's historical use by traditional practitioners.     

Temperature dependent crystallographic transformations in chalcedony, SiO2, assessed in mid infrared spectroscopy

Chalcedony consists of hydroxylated 50-100 nanometre measuring α-quartz (SiO(2)) crystallites that lose their surface silanole groups (Si-OH) upon heating between 350°C and 600°C. The loss of the chalcedony's ≈1% of silanole groups allows for the healing of water related defects in the crystallites. We investigated these crystallographic transformations using Fourier Transform mid Infrared Spectroscopy in direct transmission, Attenuated Total Reflection (ATR) and the reflectivity. We found that an absorption band that is specific for chalcedony at 555 cm(-1) disappears gradually upon heating between 350°C and 600°C. The reduction of the band is correlated to the loss of surface silanoles. This result leads to the assignment of the band to free Si-O vibrations in non bridging Si-OH groups that have a lower natural frequency than Si-O vibrations in bridging Si-O-Si. The recognition of a silanole signal in the mid infrared allows for an easy, cheap and rapid recognition of hydroxyl in chalcedony.