A Novel Method for Pattern Recognition of GIS Partial Discharge via Multi-Information Ensemble Learning

Partial discharge (PD) is the main feature that effectively reflects the internal insulation defects of gas-insulated switchgear (GIS). It is of great significance to diagnose the types of insulation faults by recognizing PD to ensure the normal operation of GIS. However, the traditional diagnosis method based on single feature information analysis has a low recognition accuracy of PD, and there are great differences in the diagnosis effect of various insulation defects. To make the most of the rich insulation state information contained in PD, we propose a novel multi-information ensemble learning for PD pattern recognition. First, the ultra-high frequency and ultrasonic data of PD under four typical defects of GIS are obtained through experiment. Then the deep residual convolution neural network is used to automatically extract discriminative features. Finally, multi-information ensemble learning is used to classify PD types at the decision level, which can complement the shortcomings of the independent recognition of the two types of feature information and has higher accuracy and reliability. Experiments show that the accuracy of the proposed method can reach 97.500%, which greatly improves the diagnosis accuracy of various insulation defects.     

林杏琴会堂的音质分析及改进设想

采用精密声级计和双通道声学分析仪，对林杏琴会堂的声场分布、噪声本底和混响时间作了分区测试，应用建筑声学理论对会堂的音质状况进行了分析，并提出改善会堂音质的若干建议．     

Necklace solitons in Bessel photonic lattice: Stability and internal oscillation

Stability, internal modes and internal oscillation of 12-pearled necklace solitons in photorefractive crystal with imprinted Bessel photonic lattices are investigated. It is shown that the imaginary parts of internal modes are negligible comparing with real parts. The stable solitons perform long-distance and quasi-periodic oscillation of intensity and shape under the perturbation of internal modes.     

Characterisation of tram noise emission and contribution of the noise sources

The recent expansion of French tram networks and the related local residential complaints mean that a better knowledge of the situations leading to negative reactions from the local inhabitants is required. Hence a research project has been conducted to evaluate and describe noise and vibration emission of trams as well as the perception by the local residents. This paper investigates tram noise emission on common straight track sections, involving two vehicle scales. First the acoustic power and the mean vertical directivity of the total tramset is assessed using an arc of microphones. Then the localisation and the analysis of the main noise sources are performed by means of a cross array during the tram pass-by. Two tram types representing two generations of French rolling stock, both running on two sites with distinct track characteristics, have been investigated considering the effect of speed, tram type, and track type on the noise source contributions and spectral features. Most sources are located in the lower part of the trams, mainly related to rolling noise, with a strong dependence on speed and track type. The tram type dependency, although globally of second importance, influences greatly the noise spectral distribution and behaviour. The HVAC was the only roof-mounted source which could be detected; its contribution towards building storeys becomes significant in configurations of low rolling noise. A tram noise emission model based on the various noise sources has been developed.     

固-液结构圆柱声子晶体中弹性波的模式和带隙

利用一维固-液结构圆柱声子晶体中弹性波横向受限的条件,推导弹性波在一维固-液结构圆柱声子晶体中各个模式满足的关系式,研究各个模式弹性波的特征.并用色散函数计算各模式弹性波的带隙随模式量子数和圆柱半径的变化规律.得出一维固-液结构圆柱声子晶体的带隙由模式量子数和圆柱半径确定.     

Preparation and Photocatalytic Performance of TiO2 Nanowire-Based Self-Supported Hybrid Membranes

Nowadays, the use of hybrid structures and multi-component materials is gaining ground in the fields of environmental protection, water treatment and removal of organic pollutants. This study describes promising, cheap and photoactive self-supported hybrid membranes as a possible solution for wastewater treatment applications. In the course of this research work, the photocatalytic performance of titania nanowire (TiO₂ NW)-based hybrid membranes in the adsorption and degradation of methylene blue (MB) under UV irradiation was investigated. Characterization techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), X-ray powder diffractometry (XRD) were used to study the morphology and surface of the as-prepared hybrid membranes. We tested the photocatalytic efficiency of the as-prepared membranes in decomposing methylene blue (MB) under UV light irradiation. The hybrid membranes achieved the removal of MB with a degradation efficiency of 90% in 60 min. The high efficiency can be attributed to the presence of binary components in the membrane that enhanced both the adsorption capability and the photocatalytic ability of the membranes. The results obtained suggest that multicomponent hybrid membranes could be promising candidates for future photocatalysis-based water treatment technologies that also take into account the principles of circular economy.     

习近平新时代中国特色社会主义思想学理化研究论纲

加强对习近平新时代中国特色社会主义思想的学理化研究具有重大理论和现实意义。开展学理化研究,一方面是要坚持以习近平新时代中国特色社会主义思想为指导,加快推动学科体系、学术体系和话语体系建设,推动构建中国特色哲学社会科学;另一方面,学理化研究可以增强对新思想的学科体系、学术体系和话语体系的有力支撑,使新思想进一步彰显其内在的学理性、创新性和整体性,从而全面系统揭示习近平新时代中国特色社会主义思想的时代性、科学性和真理性,以及彰显当代中国马克思主义理论的优秀品质和学风文风。开展学理化研究,要紧扣习近平新时代中国特色社会主义思想这一根本性主题和主线,聚焦并挖掘新思想对马克思主义理论的原创性贡献,更好体现新思想的理论创新性、价值创造性以及实践指导性。推动学理化研究,需要处理好学理化研究与党的理论宣传和贯彻落实以及与思想性和工具性、实践性和理论性、学术话语和政策话语、本土化和国际化、学理化和大众化等之间的内在关系。     

“资本主义萌芽”论范式问题再反思

在20世纪20年代末至30年代初的社会史论战中,“新生命”派、“新思潮”派和“新动力”派大都承认中国封建社会各种社会经济层次驳杂混合的格局,商业资本与封建势力之间的对立统一,也是各派的共识。论战诸派均试图以“社会形态说”诠释中国历史,以求达成对“历史整体”的把握,唯物史观从此具有了历史学的“范式”意义。在围绕《红楼梦》时代背景所展开的讨论中,学者们大致有一个基本的共识,那就是封建制度对资本主义萌芽的阻滞作用与一定程度上的让步同时并存,代表资本主义萌芽的新兴市民群体虽有一定的反抗性和独立性,但更多是一种脆弱性和依附性。后来走出“资本主义萌芽”论的吴承明和傅衣凌,在与时俱进地运用现代化理论、结构主义理论解释明清社会时,仍然将生产方式理论融入新的解释;并在传统与现代的多元互动、传统社会的多元结构等理论框架中,重新解释了“资本主义萌芽”论所面对的那些历史事实。“从社会性质出发”的唯物史观,完全可以由此走出“西方中心论”的藩篱,立足于中国历史,做出具有文明互鉴意义的历史动力学解释,形成典范性研究成果,从而彰显唯物史观和马克思主义理论的范式意义。     

水合硼酸锶的制备及脱水热分解动力学

以氯化锶和硼酸氢铵为原料,采用液相沉淀法制备了片状水合硼酸锶（SrB6O10•5H2O）粉体,并用XRD、FT-IR及SEM进行了表征。利用热重分析法对片状纳米硼酸锶粉体的脱水热分解动力学进行了研究,分别采用 Coats- Redfern 方程和 Flynn-Wall-Ozawa（FWO）法对热重分析数据进行了处理和拟合,初步确定了水合硼酸锶的四步脱水过程及相应的热分解反应机理,得到各步反应的表观活化能和指前因子。     

REACTION OF LITHIUM DERIVATIVE OF DIETHYL PHENYLMETHANE-PHOSPHONATE WITH KETONES

Abstract

The reaction of the lithium derivative of diethyl ester of phenylmethanephosphonic acid (1-Li) with alkanones, cycloalkanones, alkylaryl and diarylketones 2s-b is studied at -70°C in THF. The corresponding adducts-diethyl esters of l-phenyl-2,2-dialkyl(phenyl)-2-hydroxyethanephosphonic acids 3s-h are isolated, their yields being usually higher at short reaction time. The olefination of 3-Li as well as of 3 (both by thermolysis or in acidic media) proceeds in low degree, while in the case of 3-Na the yields of alkenes 4 are good. The relative configurations of 3b. 31 and 3g are determined by IR and NMR-spectra, as well as by their stereospecific olefination. “Threo”-stereoselectivity of the addition stage of the reaction of 1-Li with 2b, 21 and 2g is observed, the “threo”/“erythro” ratio remaining independent on the reaction time.