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Search Results: 1 - 10 of 148534 matches for " ZHANG Xin-Lin "
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Invigilation Plan Based on the Message Surveillance and Package Filtration Technique
计算机辅助测验中基于消息监控与包过滤技术的监考方法

ZHANG Xin-Lin,
张新林

计算机科学 , 2008,
Abstract: Based of computer cheating methods and aiming to the acquirement of the information by illegal program, the lawfulless program can be captured and closed forcibly when it is created and activated with the surveillance of system and process by hook functio
A comparison of hard X-ray photon indices and iron \ka emission lines in X-ray luminous narrow- and broad-line Seyfert 1 galaxies
Xin-Lin Zhou,Shuang-Nan Zhang
Physics , 2010, DOI: 10.1088/2041-8205/713/1/L11
Abstract: We use publicly available XMM-Newton data to systematically compare the hard X-ray photon indices, $\Gamma_{\rm 2-10\ keV}$ and the iron K$\alpha$ emission lines of narrow-line (NL) and broad-line Seyfert 1 (BLS1) galaxies. We compile a flux-limited ($f_{\rm 2-10\ keV} \geq 1 \times 10^{-12}$ erg s$^{-1}$ cm$^{-2}$) sample including 114 radio-quiet objects, with the 2-10 keV luminosity ranging from 10$^{41}$ to 10$^{45}$ erg s$^{-1}$. Our main results are: 1) NLS1s and BLS1s show similar luminosity distributions; 2) The weighted mean of $\Gamma_{\rm 2-10\ keV}$ of NLS1s, BLS1s and the total sample is $2.04\pm0.04$, $1.74\pm0.02$, $1.84\pm0.02$, respectively; a significant anti-correlation between \ga and FWHMH$\beta$ suggests that $\Gamma_{\rm 2-10\ keV} > 2.0$ may be taken to indicate X-ray luminous NLS1 type; 3) The 6.4 keV narrow iron K$\alpha$ lines from NLS1s are generally weaker than that from BLS1s; this would indicate a smaller covering factor of the dusty tori in NLS1s, if the line emission originates from the inner boundary region of the dusty torus in an AGN; 4) all the broadened iron K$\alpha$ lines with intrinsic width $\sigma>0.5$ keV correspond to FWHM\hb $\leq 4000 ~\kms$.
Hydriding and dehydriding kinetics of melt spun nanocrystalline Mg20Ni10-xCux (x = 0-4) alloys  [PDF]
Yang-Huan Zhang, Dong-Liang Zhao, Bao-Wei Li, Hui-Ping Ren, Shi-Hai Guo, Xin-Lin Wang
Natural Science (NS) , 2010, DOI: 10.4236/ns.2010.21003
Abstract: The nanocrystalline Mg2Ni-type electrode alloys with nominal compositions of Mg20Ni10-xCux (x = 0, 1, 2, 3, 4) were synthesized by melt-spinning technique. The microstructures of the alloys were characterized by XRD, SEM and HRTEM. The hydrogen absorption and desorption kinet-ics of the alloys were measured using an auto-matically controlled Sieverts apparatus. The re- sults show that all the as-spun alloys hold ty- pical nanocrystalline structure. The substitution of Cu for Ni does not change the major phase Mg2Ni but it leads to the formation of the sec-ondary phase Mg2Cu. The hydrogen absorption capacity of the alloys first increases and then decreases with rising Cu content, but the hy-drogen desorption capacity of the alloys mono- tonously grows with increasing Cu content. The melt spinning significantly improves the hydro- genation and dehydrogenation capacities and kinetics of the alloys.
(E)-Methyl 3-{3-[(4-bromophenoxy)methyl]phenyl}acrylate
Xin-Lin Ren,Hui-Rong Zhang,Wei-Dong Wang,Rui-Juan Tao
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536807061697
Abstract: In the molecule of the title compound, C17H15BrO3, the rings make a dihedral angle of 75.54 (17)°. In the crystal structure, intermolecular C—H...O hydrogen bonds link the molecules into centrosymmetric dimers, and the π-stacked dimers interact with neighbouring dimers via C—H...π stacking interactions.
Calibrating the correlation between black hole mass and X-ray variability amplitude: X-ray only black hole mass estimates for active galactic nuclei and ultra-luminous X-ray sources
Xin-Lin Zhou,Shuang-Nan Zhang,Ding-Xiong Wang,Ling Zhu
Physics , 2009, DOI: 10.1088/0004-637X/710/1/16
Abstract: A calibration is made for the correlation between the X-ray Variability Amplitude (XVA) and Black Hole (BH) mass. The correlation for 21 reverberation-mapped Active Galactic Nuclei (AGN) appears very tight, with an intrinsic dispersion of 0.20 dex. The intrinsic dispersion of 0.27 dex can be obtained if BH masses are estimated from the stellar velocity dispersions. We further test the uncertainties of mass estimates from XVAs for objects which have been observed multiple times with good enough data quality. The results show that the XVAs derived from multiple observations change by a factor of 3. This means that BH mass uncertainty from a single observation is slightly worse than either reverberation-mapping or stellar velocity dispersion measurements; however BH mass estimates with X-ray data only can be more accurate if the mean XVA value from more observations is used. Applying this relation, the BH mass of RE J1034+396 is found to be $4^{+3}_{-2} \times 10^6$ $M_{\odot}$. The high end of the mass range follows the relationship between the 2$f_0$ frequencies of high-frequency QPO and the BH masses derived from the Galactic X-ray binaries. We also calculate the high-frequency constant $C= 2.37 M_\odot$ Hz$^{-1}$ from 21 reverberation-mapped AGN. As suggested by Gierli\'nski et al., $M_{\rm BH}=C/C_{\rm M}$, where $C_{\rm M}$ is the high-frequency variability derived from XVA. Given the similar shape of power-law dominated X-ray spectra in ULXs and AGN, this can be applied to BH mass estimates of ULXs. We discuss the observed QPO frequencies and BH mass estimates in the Ultra-Luminous X-ray source M82 X-1 and NGC 5408 X-1 and favor ULXs as intermediate mass BH systems (abridged).
Statistical Study of 2XMMi-DR3/SDSS-DR8 Cross-correlation Sample
Zhang Yan-Xia,Zhou Xin-Lin,Zhao Yong-Heng,Wu Xue-Bing
Physics , 2013, DOI: 10.1088/0004-6256/145/2/42
Abstract: Cross-correlating the XMM-Newton 2XMMi-DR3 catalog with the Sloan Digital Sky Survey (SDSS) Data Release 8, we obtain one of the largest X-ray/optical catalogs and explore the distribution of various classes of X-ray emitters in the multidimensional photometric parameter space. Quasars and galaxies occupy different zones while stars scatter in them. However, X-ray active stars have a certain distributing rule according to spectral types. The earlier the type of stars, the stronger X-ray emitting. X-ray active stars have a similar distribution to most of stars in the g-r versus r-i diagram. Based on the identified samples with SDSS spectral classification, a random forest algorithm for automatic classification is performed. The result shows that the classification accuracy of quasars and galaxies adds up to more than 93.0% while that of X-ray emitting stars only amounts to 45.3%. In other words, it is easy to separate quasars and galaxies, but it is difficult to discriminate X-ray active stars from quasars and galaxies. If we want to improve the accuracy of automatic classification, it is necessary to increase the number of X-ray emitting stars, since the majority of X-ray emitting sources are quasars and galaxies. The results obtained here will be used for the optical spectral survey performed by the Large sky Area Multi-Object fiber Spectroscopic Telescope (LAMOST, also named the Guo Shou Jing Telescope), which is a Chinese national scientific research facility operated by the National Astronomical Observatories, Chinese Academy of Sciences.
On the Black Hole Masses In Ultra-luminous X-ray Sources
Xin-Lin Zhou
Physics , 2014, DOI: 10.1016/j.newast.2014.11.002
Abstract: Ultra-luminous X-ray sources (ULXs) are off-nuclear X-ray sources in nearby galaxies with X-ray luminosities $\geq$ 10$^{39}$ erg s$^{-1}$. The measurement of the black hole (BH) masses of ULXs is a long-standing problem. Here we estimate BH masses in a sample of ULXs with XMM-Newton observations using two different mass indicators, the X-ray photon index and X-ray variability amplitude based on the correlations established for active galactic nuclei (AGNs). The BH masses estimated from the two methods are compared and discussed. We find that some extreme high-luminosity ($L_{\rm X} >5\times10^{40}$ erg s$^{-1}$) ULXs contain the BH of 10$^{4}$-10$^{5}$ $M_\odot$. The results from X-ray variability amplitude are in conflict with those from X-ray photon indices for ULXs with lower luminosities. This suggests that these ULXs generally accrete at rates different from those of X-ray luminous AGNs, or they have different power spectral densities of X-ray variability. We conclude that most of ULXs accrete at super-Eddington rate, thus harbor stellar-mass BH.
Evaluation of safety and efficacy of gefitinib ('iressa', zd1839) as monotherapy in a series of Chinese patients with advanced non-small-cell lung cancer: experience from a compassionate-use programme
Xin-Lin Mu, Long-Yun Li, Xiao-Tong Zhang, Shu-Lan Wang, Meng-Zhao Wang
BMC Cancer , 2004, DOI: 10.1186/1471-2407-4-51
Abstract: Thirty-one patients with advanced or metastatic non-small-cell lung cancer (NSCLC) that had progressed after prior systemic chemotherapy were eligible to receive oral gefitinib 250 mg/day as part of the EAP. Treatment was continued until disease progression or unacceptable toxicity occurred. The impact of treatment on disease-related symptoms and quality of life (QoL) was evaluated with the Chinese versions of European Organization for Research and Treatment of Cancer Quality of Life Questionnaires (EORTC QLQ-C30 and QLQ-LC13).Gefitinib was well tolerated. Adverse events (AEs) were generally mild (grade1 and 2) and reversible. The most frequent AEs were acneform rash and diarrhoea. Only one patient withdrew from the study due to a drug-related AE. The objective tumour response rate was 35.5% (95% confidence interval [CI]: 18.6–52.3); median progression-free survival was 5.5 months (95% CI, 1.6 to 9.4); median overall survival was 11.5 months (95% CI, 5.6 to 17.3). The QoL response rates for five functioning scales and global QoL varied from 56–88%. The main symptom response rates varied from 44–84%. QoL and symptom response were correlated with objective tumour response.Gefitinib demonstrated safety and efficacy as monotherapy in this series of Chinese patients with advanced NSCLC and was also associated with remarkable symptom relief and improvement in QoL. Although clinical trials are needed to confirm these positive findings, the data suggest that treatment with gefitinib may be beneficial for some Chinese patients who do not respond to chemotherapy and have poor prognosis.Platinum-based combination chemotherapy is the standard first-line treatment for patients with advanced non-small-cell lung cancer (NSCLC). Although meta-analysis of clinical trials proved that combination chemotherapy for advanced NSCLC is superior to best supportive care [1] and new cytotoxic agents have been developed over the past decade, the 5-year survival rate for these patients remains
The value of contrast-enhanced ultrasound technology in the pregnancy diagnosis with caesarean scar
超声造影在剖宫产后切口妊娠诊断中的临床应用价值

LI Jian-hua,ZHANG Lei,CHEN Xin-lin,
李建华
,张磊,陈欣林

中华医学超声杂志(电子版) , 2009,
Abstract: 目的 探讨超声造影在剖宫产后切口姓娠诊断中的应用价值.方法 对9例常规超声诊断为剖宫产切口妊娠的患者行超声造影检查,比较二维超声、彩色多普勒超声及超声造影检查结果.结果 二维超声、超声造影检查均可显示病灶部位、大小;彩色多普勒超声显示8例病灶内无血流信号,1例有血流信号.7例剖宫产后切口处病灶与肌壁界限二维超声显示不清者超声造影剂灌注可判断子宫浆膜层和肌层的完整性,并可辨别病灶与浆膜、肌壁的关系.结论 超声造影可为剖宫产切口处妊娠诊断提供更丰富的信息.
Correction method for moving target location with mobile nodes
一种移动节点定位活动目标的校正方法

ZHANG Xin-lin,CHEN Yuan,ZENG De-sheng,
张新林
,陈源,曾德胜

计算机应用研究 , 2009,
Abstract: 为了消除测距定位追踪活动目标的测量误差,通过利用四个移动传感器感知活动目标M,由任意三个传感器所得的信息计算出目标M的位置分别为M1、M2、M3、M4,由其四点所围成的凸区域的形心或其所围成的凹区域的主骨架线中点M′作为逼近点替代目标M,从而消除由测量引起的误差。在MATLAB环境中进行仿真实验,表明用四个移动信源节点追踪活动目标M的方法可消除测量误差,M′成功逼近目标M。
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