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An explanation about the flat radio spectrum for Mrk 421

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Research in Astronomy and Astrophysics 2021年第4期21卷 311-318页

作者： rui xue Ze-rui Wang Department of Physics Zhejiang Normal UniversityJinhua 321004China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China

It is well known that a flat radio spectrum is a common property in the spectral energy distribution of *** one-zone leptonic models are generally successful in explaining the multi-wave band emission,they are problematic in reproducing the radio *** the study of Mrk 421,one-zone models suggest that in order to avoid overproducing the radio flux,the minimum electron Lorentz factor should be larger than a few hundred at least,even considering the synchrotron self-absorption *** result suggests that the model predicted spectral index in the radio band of Mrk 421 should be-1/*** the basis of this result,by assuming there is a neglected region that will also contribute the radio emission and its electron energy index naturally originates from the simplest first-order Fermi acceleration mechanism,we can get a superimposed flat radio *** this paper,a two-zone model is proposed to reproduce the quiescent state spectral energy distribution of Mrk *** addition to taking into account the emission from a conventional radiation zone,we further consider emission from the acceleration zone in which particles are accelerated at a shock *** the present model,our fitting result suggests that the low frequency flat radio spectrum of Mrk 421 might be explained as a superposition of the synchrotron emission from acceleration zone and radiation zone.

关键词： galaxies:active galaxies:jets radiation mechanisms:non-thermal

Hadronuclear interpretation of the possible neutrino emission from PKS B1424-418,GB6 J1040+0617 and PKS 1502+106

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Research in Astronomy and Astrophysics 2021年第12期21卷 375-382页

作者： Ze-rui Wang rui xue College of Physics and Electronic Engineering Qilu Normal UniversityJinhua 321004China Department of Physics Zhejiang Normal UniversityJinan 250200China

In addition to neutrino event IceCube-170922 A which is observed to be associated with aγ-ray flare from blazar TXS 0506+056,there are also several neutrino events that may be associated with *** them,PKS B1424-418,GB6 J1040+0617 and PKS 1502+106 are low synchrotron peaked sources,which are usually believed to have the broad line region in the vicinity of the central black *** are considered as counterparts of IceCube event 35,IceCube-141209 A and IceCube-190730 A,*** considering the proton-proton(pp)interactions between the dense gas clouds in the broad line region and the relativistic protons in the jet,we show that the pp model that is applied in this work can not only reproduce the multi-waveband spectral energy distribution but also suggest a considerable annual neutrino detection *** also discuss the emission from the photopion production and Bethe-Heitler pair production with a sub-Eddington jet power that is suggested in our model and find that it has little effect on the spectrum of total emission for all of three sources.

关键词： neutrinos galaxies:active galaxies:jets radiation mechanisms:non-thermal

A novel LAAS pseudo-range error over-bound method based on improved pseudo-range error distribution model

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Chinese Journal of Aeronautics 2013年第3期26卷 638-645页

作者： xue rui Wang Zulin School of Electronics and Information Engineering Beihang University

The high level of safety demand of civil aviation requests local area augmentation system （LAAS） extremely high navigation integrity performance. A new LAAS pseudo-range error overbound method is proposed in this paper to improve the integrity of LAAS. Firstly, a more practical pseudo-range error distribution model is established. Then, by calculating the relationship between the statistical uncertainty of the model parameter and the integrity risk, a new method is proposed to calculate the pseudo-range error over-bound model. This method can effectively reduce the inflation factor and the resulting conservativeness of the over-bound model. Comparative experiments show that the method proposed in this paper performs better and satisfies the requirements of real applications.

关键词： Augmentation system Error statistics Probability density function Parameter estimation Satellite navigation Signal analysis Uncertainty analysis

Improved lower bound for the complexity of unique shortest vector problem

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Cybersecurity 2024年第3期7卷 102-110页

作者： Baolong Jin rui xue State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of SciencesBeijing 100085China School of Cyber Security University of Chinese Academy of SciencesBeijing 100049China

Unique shortest vector problem(uSVP)plays an important role in lattice based *** cryptographic schemes based their security on *** the cofidence of those applications,it is essential to clarify the complex-ity of uSVP with different ***,proving the NP-hardness of usVP appears quite *** the state of the art,we are even not able to prove the NP-hardness of usVP with constant *** this work,we gave a lower bound for the hardness of usVP with constant parameters,*** proved that uSVP is at least as hard as gap shortest vector problem(GapSVP)with gap of O(√n/log(n)),which is in NP n *** previous works,our reduction works for paramters in a bigger range,especially when the constant hidden by the big-O in GapsVP is smallerthan1.

关键词： Computational complexity Unique shortest vector problem Bounded distance decoding Complexity reduction

PDR diagnostics study with CLOUDY

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Chinese Journal of Astronomy and Astrophysics 2009年第4期9卷 457-469页

作者： rui xue Maohai Huang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

A series of plane-parallel photodissociation region （PDR） models are calculated using the spectral synthesis code CLOUDY. These models span a wide range of physical conditions, with gas densities of n=10^2-10^6cm^-3 and incident far-ultraviolet （FUV） fields of Go=10^0-10^6 （where Go is the FUV flux in units of the local interstellar value）, which are comparable with various astrophysical environments from interstellar diffuse clouds to the dense neutral gas around galactic compact H Ⅱ regions. Based on the calculated results, we study the thermal balance of PDR gas and the emissions of [C Ⅱ], [C I] and [O I] fine-structure lines under different physical conditions. The intensities and strength ratios of the studied lines, which are frequently used as PDR diagnostics, are presented using contour diagrams as functions of n and Go. We compare the calculated PDR surface gas temperatures Ts with those from Kaufman et al. and find that Ts from our models are systematically higher over most of the adopted n-Go parameter space. The predicated line intensities and ratios from our work and those from Kaufman et al. can be different by a factor greater than 10, and such large differences usually occur near the border of our parameter space. The different methods of treating the dust grain physics, the change of H2 formation and dissociation rates, and the improvement in the radiation transfer of line emissions in our CLOUDY models are likely to be the major reasons for the divergences. Our models represent an up-to-date treatment of PDR diagnostic calculations and can be used to interpret observational data. Meanwhile, the uncertainties in the treatment of microphysics and chemical processes in PDR models have significant effects on PDR diagnostics.

关键词： infrared ISM-ISM clouds-ISM molecules-methods numerical

Leveraged fault identification method for receiver autonomous integrity monitoring

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Chinese Journal of Aeronautics 2015年第4期28卷 1217-1225页

作者： Sun Yuan Zhang Jun xue rui School of Electronic and Information Engineering Beihang University

Receiver autonomous integrity monitoring（RAIM） provides integrity monitoring of global positioning system（GPS） for safety-of-life *** the process of RAIM, fault identification（FI） enables navigation to continue in the presence of fault *** by satellite geometry, the leverage of each measurement in position solution may differ ***, the conventional RAIM FI methods are generally based on maximum likelihood of ranging error for different measurements, thereby causing a major decrease in the probability of correct identification for the fault measurement with high *** this paper, the impact of leverage on the fault identification is *** leveraged RAIM fault identification（L-RAIM FI） method is proposed with consideration of the difference in leverage for each satellite in ***,the theoretical probability of correct identification is derived to evaluate the performance of L-RAIM FI *** experiments in various typical scenarios demonstrate the effectiveness of L-RAIM FI method over conventional FI methods in the probability of correct identification for the fault with high leverage.

关键词： Fault identification Global positioning system Leverage Navigation systems Receiver autonomousintegrity monitoring

Improved iterative convergence method in Q-ary LDPC coded high order PR-CPM

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Journal of Systems Engineering and Electronics 2016年第3期27卷 541-548页

作者： Danfeng Zhao Yanbo Sun rui xue College of Information and Communication Engineering Harbin Engineering University

The Q-ary low-density parity-check（LDPC） coded high order partial response continuous phase modulation（PR-CPM） with double iterative loops is investigated. This scheme shows significant improvements in power and bandwidth efficiency, but at the expense of long iterative decoding delay and computational complexity induced by the improper match between the demodulator and the decoder. To address this issue, the convergence behavior of Q-ary LDPC coded CPM is investigated for the Q=2 and Q〉2 cases, and an optimized design method based on the extrinsic information transfer chart is proposed to improve the systematic iterative efficiency. Simulation results demonstrate that the proposed method can achieve a perfect tradeoff between iterative decoding delay and bit error rate performance to satisfy real-time applications.

关键词： iterative detection convergence low-density paritycheck(LDPC) code continuous phase modulation(CPM) extrinsic information transfer chart

Si掺杂对Ga_(2)O_(3)/BP异质结光电性能调控的第一性原理研究

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原子与分子物理学报 2025年第4期42卷 131-137页

作者：李佳宏郝增瑞薛瑞鑫阚红梅关玉琴内蒙古工业大学理学院呼和浩特010010

近年来,氧化镓(Ga_(2)O_(3))是新一代超宽禁带(4.9 eV)半导体,基于优越的热稳定和化学稳定性、高击穿场强和可见光透过率等优点,在日盲紫外探测器和透明光电器件领域中引起了广泛的关注.但是,Ga_(2)O_(3)基光电器件存在迁移率较低而限... 详细信息

近年来,氧化镓(Ga_(2)O_(3))是新一代超宽禁带(4.9 eV)半导体,基于优越的热稳定和化学稳定性、高击穿场强和可见光透过率等优点,在日盲紫外探测器和透明光电器件领域中引起了广泛的关注.但是,Ga_(2)O_(3)基光电器件存在迁移率较低而限制其应用的现象,而构建合适的Ga_(2)O_(3)异质结是改善光电探测器的光电性能的有效手段之一.基于第一性原理构建β-Ga_(2)O_(3)/BP异质结模型,研究了氧空位(Vo)和Si掺杂对β-Ga_(2)O_(3)/BP异质结光电性质的调控以及相关机理.结果显示:β-Ga_(2)O_(3)/BP异质结结构有效降低β-Ga_(2)O_(3)功函数,提高灵敏度,Si掺杂降低结合能,增强稳定性;β-Ga_(2)O_(3)/BP异质结有效减小带隙,Si掺杂以及氧空位的存在,进一步减小带隙,增强光导电性,并且Si掺杂引起了光电导各向异性.此结果对改善Ga_(2)O_(3)基异质结光电性能提供理论参考.

关键词： β-Ga_(2)O_(3)/BP异质结缺陷光电性质第一性原理

DNA damage response signaling pathways and targets for radiotherapy sensitization in cancer

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Signal Transduction and Targeted Therapy 2020年第1期5卷 1925-1951页

作者： rui-xue Huang Ping-Kun Zhou Department of Occupational and Environmental Health Xiangya School of Public HealthCentral South University410078 ChangshaPeople’s Republic of China Department of Radiation Biology Beijing Key Laboratory for RadiobiologyBeijing Institute of Radiation MedicineAMMS100850 BeijingPeople’s Republic of China Institute for Chemical Carcinogenesis State Key Laboratory of RespiratoryGuangzhou Medical University511436 GuangzhouPeople’s Republic of China

Radiotherapy is one of the most common countermeasures for treating a wide range of ***,the radioresistance of cancer cells is still a major limitation for radiotherapy *** are continuously ongoing to explore sensitizing targets and develop radiosensitizers for improving the outcomes of *** double-strand breaks are the most lethal lesions induced by ionizing radiation and can trigger a series of cellular DNA damage responses(DDRs),including those helping cells recover from radiation injuries,such as the activation of DNA damage sensing and early transduction pathways,cell cycle arrest,and DNA ***,these protective DDRs confer tumor *** DDR signaling pathways has become an attractive strategy for overcoming tumor radioresistance,and some important advances and breakthroughs have already been achieved in recent *** the basis of comprehensively reviewing the DDR signal pathways,we provide an update on the novel and promising druggable targets emerging from DDR pathways that can be exploited for *** further discuss recent advances identified from preclinical studies,current clinical trials,and clinical application of chemical inhibitors targeting key DDR proteins,including DNA-PKcs(DNA-dependent protein kinase,catalytic subunit),ATM/ATR(ataxia–telangiectasia mutated and Rad3-related),the MRN(MRE11-RAD50-NBS1)complex,the PARP(poly[ADP-ribose]polymerase)family,MDC1,Wee1,LIG4(ligase IV),CDK1,BRCA1(BRCA1 C terminal),CHK1,and HIF-1(hypoxia-inducible factor-1).Challenges for ionizing radiation-induced signal transduction and targeted therapy are also discussed based on recent achievements in the biological field of radiotherapy.

关键词： damage radiotherapy injuries