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Spectral indices for radio emission of 228 pulsars

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Research in Astronomy and Astrophysics 2016年第10期16卷 81-92页

作者： jun han Chen Wang jun Xu Jin-Lin han National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China School of Astronomy University of Chinese Academy of Sciences Beijing 100049 China

We determine spectral indices of 228 pulsars by using Parkes pulsar data observed at 1.4 GHz, among which 200 spectra are newly determined. The indices are distributed in the range from -4.84 to -0.46. Together with known pulsar spectra from literature, we tried to find clues to the pulsar emission process. The wealCcorrelations between the spectral index, the spin-down energy loss rate E and the poten- tial drop in the polar gap Aψ hint that emission properties are related to the particle acceleration process in a pulsar＇s magnetosphere.

关键词： pulsars: general -- radiation mechanisms: general -- radio continuum: general

Preliminary study on active features of Fenghuang-shan-Tianshui fault, West Qinling north boundary fault zone since the late of Late Pleistocene

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Acta Seismologica Sinica(English Edition) 2001年第2期14卷 230-233页

作者： han Zhu-jun Institute of Geology China Seismological Bureau Beijing China

West Qinling north boundary fault zone (WQNBFZ) is a major NWW-striking fault in the east boundary of Tibetan Plateau, which is parallel to the Xianshuihe fault zone, Eastern Kunlun fault zone and Haiyuan fault zone. It is of mainly sinistral strike-slip. England and Molnar (1990) and WANG and MA (1998) proposed that these strike-slip faults divided the east part of Tibetan Plateau into elongate blocks, which slide successively towards the east, accompanied possibly by the clockwise rotation. What is more, the occurrence frequency of earthquakes with M 36.5 along WQNBFZ is also high, such as BC 47 Zhangxian M=6.8 earthquake, the 128 Gangu M=6.5 earth-quake, the 143 Gangu M=7 earthquake, the 734 Tianshui M=7 earthquake, the 1756 Wushan M=6.5 earthquake and the 1936 Kangle M=6.8 earthquake. However, compared with researches on Haiyuan fault zone, Xianshuihe fault zone and Longmenshan fault zone (Institute of Geology of State Seismological Bureau, Seismological Bureau of Ningxia Hui Autonomous Region, 1990; LI, 1993; DENG, et al, 1994; Burchfiel, et al, 1995), the study on WQNBFZ is still weak, although some researches have been done by KANG (1990) and TENG, et al (1991). Based on the field investigation and sample dating, the active features about the Fenghuangshan-Tianshui fault (FTF) of WQNBFZ are discussed in the paper.……

关键词： Late Pleistocene

INTERFACIAL BEHAVIOR OF PIPE JOINTS UNDER TORSION LOADS

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Acta Mechanica Solida Sinica 2015年第5期28卷 521-535页

作者： jun han Hong Yuan Jiayu Wu MOE Key Lab of Disaster and Control in Engineering Institute of Applied Mechanics Jinan University

The interfacial behavior of pipe joints is studied in this paper. Firstly, through nonlinear fracture mechanics, the analytical expressions of interfacial shear stress and the load- displacement relationship at loaded end of pipe joints under torsion loads are obtained. Thus the shear stress propagation and the debonding process of the whole interface for different bond lengths can be predicted. Secondly, through the analytical solutions, the influences of different bond lengths on the load-displacement curve and the ultimate load are studied. The stress trans- fer mechanism, the interface crack propagation and the ductility behavior of the joints can be explained.

关键词： interface failure mechanism softening debonding torsion pipe joints

VCNet:A generative model for volume completion

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Visual Informatics 2022年第2期6卷 62-73页

作者： jun han Chaoli Wang Department of Computer Science&Engineering University of Notre DameNotre DameIN 46556United States

We present VCNet,a new deep learning approach for volume completion by synthesizing missing *** solution leverages a generative adversarial network(GAN)that learns to complete volumes using the adversarial and volumetric *** core design of VCNet features a dilated residual block and long-term *** training,VCNet first randomly masks basic subvolumes(e.g.,cuboids,slices)from complete volumes and learns to recover ***,we design a two-stage algorithm for stabilizing and accelerating network *** trained,VCNet takes an incomplete volume as input and automatically identifies and fills in the missing subvolumes with high *** quantitatively and qualitatively test VCNet with volumetric data sets of various characteristics to demonstrate its *** also compare VCNet against a diffusion-based solution and two GAN-based solutions.

关键词： Volume visualization Generative adversarial network Data completion

Efficiency of Different Methods for dsRNA Delivery in Cotton Bollworm(Helicoverpa armigera)

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Journal of Integrative Agriculture 2014年第1期13卷 115-123页

作者： YANG Jing han Zhao-jun Key Laboratory of Integrated Management of Crop Diseases and Pests Ministry of Education/College of Plant ProtectionNanjing Agricultural University

RNAi trigged by dsRNA not only facilitates the development of molecular biology, but also initiates a new way for pest control by silence of fatal genes. However, one of the key limitations in pest control is lack of the convenient and efficient method for dsRNA delivery. In this study, different dsRNA delivery methods at their own optimum conditions were evaluated comparatively for their efficiency with Helicoverpa armigera as test animal. It was found that the popular one- time injection of larvae with dsRNA could reduce the pupation rate by 43.0% and enhance larva mortality by 11.7%. One- time ingestion of dsRNA did not result in any significant effect on phenotype. Continuous ingestion of in vitro synthesized dsRNA by refreshing the bait diet every day caused 40.4% decrease in successful pupation and 10.0% increase in larval mortality, which was similar as one-time injection. The most efficient method was found to be the continuous ingestion of the bacteria containing dsRNA expressed, which reduced the rate of pupation by 68.7% and enhanced the larval mortality by 34.1%. Further analysis found that dsRNA was degraded faster in midgut juice than in hemolymph. However, the cell of bacteria could protect dsRNA and delay the degradation in the midgut juice of H. armigera. These results throw light on the application of dsRNA in pest management with proper ways.

关键词： Helicoverpa armigera dsRNA delivery methods RNAi effect pest control

Voltage-induced material removal mechanism of copper for electrochemical-mechanical polishing applications

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中国有色金属学会会刊：英文版 2009年第B9期19卷 262-265页

作者： Sang-jun han Yong-Jin SEO Nano-Information Material ＆ Device Laboratory Daebul University Chonnam 526-702 Korea School of Fusion Technology Daebul University Chonnam 526-702 Korea

The current-voltage (I-V) curves, such as linear sweep voltammetry (LSV) and cyclic voltammetry (CV), were employed to evaluate the effect of electrolyte concentration on the electrochemical reaction trend. From the I-V curve, the electrochemical states of active, passive, transient and trans-passive region could be characterized. And then, the mechanism of the process of voltage-induced material removal in electrochemical mechanical polishing (ECMP) of copper was investigated. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analyses were used to observe the surface profile. Finally, the oxidation and reduction processes of the Cu surface were monitored by the repetition of anodic and cathodic potential from cyclic voltammetry (CV) method in acid-and alkali-based electrolyte.

关键词：电化学机械抛光材料去除机理铜电极电压诱导线性扫描伏安法扫描电子显微镜循环伏安法

A Simple Proof of ACC for Minimal Log Discrepancies for Surfaces

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Acta Mathematica Sinica,English Series 2024年第2期40卷 425-434页

作者： Jing jun han Yu Jie LUO Shanghai Center for Mathematical Sciences Fudan UniversityJiangwan CampusShanghai 200438P.R.China Department of Mathematics Johns Hopkins UniversityBaltimoreMD 21218USA

Following Shokurov's idea,we give a simple proof of the ACC conjecture for minimal log discrepancies for surfaces.

关键词： Ascending chain condition minimal log discrepancies minimal model program surface

Synthesis of Calix[4]resorcinarene Core Dendrimers with Peripheral Salicylideneimine Functional Groups

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Chemical Research in Chinese Universities 2006年第4期22卷 537-542页

作者： han jun GE Yun YAN Chao-guo College of Chemistry ＆ Chemical Engineering Yangzhou University Yangzhou 225002 P. R. China

First to third-generation calix[4] resorcinarene core dendrimers, compounds 4a, 4b, 7a, 7b, 10a and 10b, were prepared via the divergent method in seven steps with the corresponding tetraphenyl- and tetra （hydroxyphenyl） calix[4] resorcinarenes （compounds 1a, 1b） as the starting material. The repeat units of the polyamidoamines of these dendrimers were obtained by the ammonolysis of ethyl calixarylacetates 2a and 2b with 1,3-diaminopropane, that is, amide derivatives with terminal amino groups, which in turn reacted with ethyl acrylate to give a higher generation of ester derivatives. The structures of these dendrimers were characterized by IR, ^1H and ^13C NMR spoctrometries. The crystal structure of compound 2b with 12 ethoxycarbonylmethoxy groups was determined by X-ray analysis.

关键词： Calixresorcinarene Dendrimer Schiffbase Amide Calixarene

CFAR Block-Sparse Bayesian Learning Algorithm for the Off-grid DOA Estimation with Coprime Array

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Chinese Journal of Electronics 2019年第4期28卷 863-870页

作者： han jun HE Minghao FENG Mingyue JIANG Ying Air Force Early Warning Academy

Constant false-alarm rate Block-sparse Bayesian learning(CFAR-BSBL) algorithm is proposed to reduce the computational complexity and improve Direction of arrival(DOA) estimation accuracy of offgrid signals with coprime array. Firstly, a signal model with normalized noise is built to avoid the learning procedure of noise parameter. Secondly, a block sparse Bayesian framework is built with the introduction of a temporary correlation matrix in order to use t he temporal structure of incident signals. Then the algorithm uses CFAR detection to detect the grids close to the real DOA and relieve the dependence on the number of signals. Finally,an off-grid process based on the closest grids is adopted to deal with the off-grid problem. The proposed CFAR-BSBL algorithm can obtain high accuracy and low complexity DOA estimation of off-grid signals with coprime array.

关键词： Off-grid direction-of-arrival estimation Block sparse Bayesian learning(BSBL) Coprime array CFAR detection Low complexity