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Research in Astronomy and Astrophysics 2014年第4期14卷 401-410页

作者： xin-Fa deng School of Science Nanchang University

Using the LOWZ and CMASS samples of the ninth data release （DR9） from the SDSS-III Baryon Oscillation Spectroscopic Survey （BOSS）, I investigate properties of star forming galaxies and active galactic nuclei （AGNs）. The CMASS sample seriously suffers from the radial selection effect, even within the redshift 0.44 〈 z 〈 0.6, which will likely lead to statistical conclusions in the CMASS sample being less robust. In the LOWZ sample, the fraction of star-forming galaxies is nearly constant from the least dense regime to the densest regime; the AGN fraction is also insensitive to the local environment. In addition, I note that in the LOWZ sample, the distributions of stellar mass and stellar velocity dispersion for star forming galaxies and AGNs are nearly the same.

关键词： galaxies: active- galaxies: statistics

A tool for the morphological classification of galaxies: the concentration index

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Research in Astronomy and Astrophysics 2013年第6期13卷 651-661页

作者： xin-Fa deng School of Science Nanchang University

Using galaxy data from the Sloan Digital Sky Survey Data Release 8, I ex- plore whether the concentration index is a good morphological classification tool and find that a reasonable sample of pure late-type galaxies can be constructed with the choice of the r-band concentration index ci=2.85. The opposite is not true, however, due to the fairly high contamination of an early-type sample by late-type galaxies. In such an analysis, the influence of selection effects is less important. To disentangle correlations of the morphology and concentration index with stellar mass, star forma- tion rate （SFR）, specific star formation rate （SSFR） and active galactic nucleus （AGN） activity, I investigate correlations of the concentration index with these properties at a fixed morphology and correlations of the morphology with these properties at a fixed concentration index. It is found that at a fixed morphology, high-concentration galaxies are preferentially more massive and have a lower SFR and SSFR than low- concentration galaxies, whereas at a fixed concentration index, elliptical galaxies are preferentially more massive and have a lower SFR and SSFR than spiral galaxies. This result shows that the stellar mass, SFR and SSFR of a galaxy are correlated with its concentration index as well as its morphology. In addition, I note that AGNs are pref- erentially found in more concentrated galaxies only in the sample of spiral galaxies.

关键词： galaxies: fundamental parameters -- galaxies: statistics

The environmental dependence of different colors in the CMASS sample of the SDSS DR9

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Research in Astronomy and Astrophysics 2014年第5期14卷 553-564页

作者： xin-Fa deng School of Science Nanchang University

I investigate the environmental dependence of galaxy colors in the CMASS sample of the Sloan Digital Sky Survey Data Release 9 （SDSS DR9）. To decrease the radial selection effect, I divide the CMASS sample into subsamples with a redshift binning size of △z = 0.01 and analyze the environmental dependence of the u - r, u - g, g - r, r - i and i - z colors for these subsamples in each redshift bin. Statistical analysis shows that all five colors weakly correlate with the local environment, which may mean that the environmental processes responsible for a galaxy＇s properties pro- ceed slowly over cosmic time.

关键词： galaxies fundamental parameters -- galaxies statistics

Aerodynamic interaction between forewing and hindwing of a hovering dragonfly

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Acta Mechanica Sinica 2014年第6期30卷 787-799页

作者： Zheng Hu xin-Yan deng School of Mechanical Engineering Purdue University 585 Purdue MallWest Lafayette IN 47906 USA

The phase change between the forewing and hindwing is a distinct feature that sets dragonfly apart from other *** this paper,we investigated the aerodynamic effects of varying forewing-hindwing phase di ff erence with a60 inclined stroke plane during hovering *** measurements on a pair of mechanical wing models showed that in-phase flight enhanced the forewing lift by 17%and the hindwing lift was reduced at most phase *** total lift of both wings was also reduced at most phase di ff erences and only increased at a phase range around *** results may explain the commonly observed behavior of the dragonfly where 0 is employed in *** further investigated the wing-wing interaction mechanism using the digital particle image velocimetry（PIV）system,and found that the forewing generated a downwash flow which is responsible for the lift reduction on the *** the other hand,an upwash flow resulted from the leading edge vortex of the hindwing helps to enhance lift on the *** results suggest that the dragonflies alter the phase di ff erences to control timing of the occurrence of flow interactions to achieve certain aerodynamic effects.

关键词： Dragonfly aerodynamics Forewing-hindwing interaction Phase di ff erence Interactive flow

Reachability of Patterned Conditional Pushdown Systems

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Journal of Computer Science & Technology 2020年第6期35卷 1295-1311页

作者： xin Li Patrick Gardy Yu-xin deng Hiroyuki Seki Shanghai Key Laboratory of Trustworthy Computing East China Normal UniversityShanghai 200062China Graduate School of Informatics Nagoya UniversityNagoya 464-8601Japan

Conditional pushdown systems (CPDSs) extend pushdown systems by associating each transition rule with a regular language over the stack alphabet. The goal is to model program verification problems that need to examine the run-time call stack of programs. Examples include security property checking of programs with stack inspection, compatibility checking of HTML5 parser specifications, etc. Esparza et al. proved that the reachability problem of CPDSs is EXPTIME-complete, which prevents the existence of an algorithm tractable for all instances in general. Driven by the practical applications of CPDSs, we study the reachability of patterned CPDS (pCPDS) that is a practically important subclass of CPDS, in which each transition rule carries a regular expression obeying certain patterns. First, we present new satura-tion algorithms for solving state and configuration reachability of pCPDSs. The algorithms exhibit the exponential-time complexity in the size of atomic patterns in the worst case. Next, we show that the reachability of pCPDSs carrying sim-ple patterns is solvable in fixed-parameter polynomial time and space. This answers the question on whether there exist tractable reachability analysis algorithms of CPDSs tailored for those practical instances that admit efficient solutions such as stack inspection without exception handling. We have evaluated the proposed approach, and our experiments show that the pattern-driven algorithm steadily scales on pCPDSs with simple patterns.

关键词： conditional pushdown system pattern reachability saturation algorithm

Dynamic response of buildings under debris flow impact

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Journal of Mountain Science 2024年第5期21卷 1581-1597页

作者： LIU Huan FAN Xiaoyi TIAN Shujun deng xin School of Mechanical and Electrical Engineering Southwest Petroleum UniversityChengdu 610500China School of Civil Engineering and Geomatics Southwest Petroleum UniversityChengdu 610500China Housing and Urban-Rural Development Bureau of Mingshan District Ya’an 625100China Engineering Safety Assessment and Protection Research Southwest Petroleum UniversityChengdu 610500China School of Civil Engineering and Architecture Southwest University of Science and TechnologyMianyang 621010China

This study employs the smoothed particle hydrodynamics–finite element method(SPH–FEM) coupling numerical method to investigate the impact of debris flow on reinforced concrete(RC)-frame buildings. The methodology considers the variables of debris flow depth and velocity and introduces the intensity index IDV(IDV = DV) to evaluate three different levels of debris flow impact intensity. The primary focus of this study is to investigate the dynamic response and failure mechanism of RC-frame buildings under debris flow impact, including structural failure patterns, impact force and column displacement. The results show that under a highintensity impact, a gradual collapse process of the RCframe building can be observed, and the damage mode of the frame column reflects shear failure or plastic hinge failure mechanism. First, the longitudinal infill walls are damaged owing to their low out-of-plane flexural capacity;the critical failure intensity index IDV value is approximately 7.5 m2/s. The structure cannot withstand debris flows with an intensity index IDV greater than 16 m2/s, and it is recommended that the peak impact force should not exceed 2100 k N. The impact damage ability of debris flow on buildings mostly originates from the impact force of the frontal debris flow, with the impact force of the debris flow body being approximately 42% lower than that of the debris flow head. Finally, a five-level classification system for evaluating the damage status of buildings is proposed based on the numerical simulation and investigation results of the disaster site.

关键词： SPH–FEM method Debris flow Buildings The intensity index Dynamic response

Multi-class classification method for steel surface defects with feature noise

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Journal of Iron and Steel Research International 2021年第3期28卷 303-315页

作者： Mao-xiang Chu Yao Feng Yong-hui Yang xin deng School of Electronic and Information Engineering University of Science and Technology LiaoningAnshan114051LiaoningChina

Defect classification is the key task of a steel surface defect detection *** current defect classification algorithms have not taken the feature noise into *** order to reduce the adverse impact of feature noise,an anti-noise multi-class classification method was proposed for steel surface *** the one hand,a novel anti-noise support vector hyper-spheres(ASVHs)classifier was *** N types of defects,the ASVHs classifier built N *** hyper-spheres were insensitive to feature and label *** the other hand,in order to reduce the costs of online time and storage space,the defect samples were pruned by support vector data description with parameter iteration adjustment *** the end,the ASVHs classifier was built with sparse defect samples set and auxiliary *** results show that the novel multi-class classification method has high efficiency and accuracy for corrupted defect samples in steel surface.

关键词： Steel surface defect Multi-class classification Anti-noise support vector hyper-sphere Parameter iteration adjustment Feature noise

Confidential Image Super-Resolution with Privacy Protection

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Chinese Journal of Electronics 2024年第6期33卷 1447-1457页

作者： Yiran HAN Jianwei LIU xin deng Junpeng JING Yanting ZHANG School of Cyber Science and Technology Beihang University Beihang University Hangzhou Innovation Institute China Electronics Standardization Institute

Nowadays, people are getting used to upload images to a third party for post-processing, such as image denoising and super-resolution. This may easily lead to the disclosure of the privacy in the confidential images. One possible solution is to encrypt the image before sending it to the third party, the encrypted image can be easily detected by a malicious attacker in the transmission channel. We propose a confidential image super-resolution method named HSR-Net which firstly hide the secret image and then super-resolve it in the hidden domain. The method is composed of three important modules: image hiding module(IHM), image super-resolution module(ISM), and image revealing module(IRM). The IHM aims to encode secret image and hide it into a cover image to generate the stego image. The stego image looks similar to the cover image but contains the information of the secret image. The third party uses the ISM to perform image super-resolution on the stego image. The user can reveal the super-resolved secret image from the stego image. The proposed HSR-Net method has two advantages. It ensures that the third party cannot directly operate on the secret image, thus protecting the user's privacy. Due to the similarity between the stego image and cover image, we can reduce the attacker's suspicion to further improve the image security. The experimental results were tested on DIV2K dataset and Flickr2K dataset. The peak signal-to-noise ratios(PSNR) of IHM, ISM, and IRM are 38.81 dB, 28.91 dB, and 23.51 dB, respectively, which verify that the proposed HSR-Net method is able to achieve image super-resolution and protect user's privacy simultaneouly.

关键词： Privacy Data privacy PSNR Superresolution Cryptography Protection Signal resolution Image denoising

Organotellurium-catalyzed oxidative deoximation reactions using visible-light as the precise driving energy

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Chinese Chemical Letters 2021年第3期32卷 1029-1032页

作者： xin deng Rongrong Qian Hongwei Zhou Lei Yu School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China College of Biological Chemical Sciences and EngineeringJiaxing UniversityJiaxing 314001China Jiangsu College of Tourism Yangzhou 225127China

Irradiated by visible light,the recyclable(PhTe)2-catalyzed oxidative deoximation reaction could occur under mild *** comparison with the thermo reaction,the method employed reduced catalyst loading(1 mol%vs.2.5 mol%),but afforded elevated product yields with expanded substrate *** work demonstrated that for the organotellurium-catalyzed reactions,visible light might be an even mo re precise driving energy than heating because it could break the Te—Te bond accurately to generate the active free radical catalytic intermediates without damaging the fragile substituents(e.g.,heterocycles)of *** use of O_(2) instead of explosive H_(2)O_(2) as oxidant affords safer reaction conditions from the large-scale application viewpoint.

关键词： Photocatalysis Tellurium Deoximation Sustainable energy Ketone

Differential Evolution Based High-order Peak Filter Design with Application to Compensation of Contact-induced Vibration in HDD Servo Systems

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International Journal of Automation and computing 2017年第1期14卷 45-56页

作者： Deqing Huang Jian-xin Xu xin deng Venkatakrishnan Venkataramanan The Cat Tuong Huynh Institute of Systems Science and Technology School of Electrical Engineering Southwest Jiaotong University Department of Electrical and Computer Engineering National University of Singapore Chongqing Key Laboratory of Computational Intelligence Chongqing University of Posts and Telecommunications Data Storage Institute Agency for Science Technology and Research

Sensitivity loop shaping using add-on peak filters is a simple and effective method to reject narrow-band disturbances in hard disk drive （HDD） servo systems. The parallel peak filter is introduced to provide high-gain magnitude in the concerned frequency range of open-loop transfer function. Different from almost all the known peak filters that possess second-order structures, we explore in this paper bow high-order peak filters can be designed to improve the loop shaping performance. The main idea is to replace some of the constant coefficients of common second-order peak filter by frequency-related transfer functions, and then differential evolution （DE） algorithm is adopted to perform optimal design. We creatively introduce chromosome coding and fitness function design, which are original and the key steps that lead to the success of DE applications in control system design. In other words, DE is modified to achieve a novel design for hard disk drive control. Owing to the remarkable searching ability of DE, the expected shape of sensitivity function can be achieved by incorporating the resultant high-order peak filter in parallel with baseline feedback controller. As a result, a seventh-order peak filter is designed to compensate for contact-induced vibration in a high-density HDD servo system, where the benefits of high-order filter are clearly demonstrated.

关键词： Differential evolution (DE) contact-induced vibration peak filter optimization sensitivity loop shaping hard disk drive(HDD).