分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： Cassiopeia A (Cas A) is a well-known candidate for studying cosmic-ray acceleration, in which compact features of various scales have attracted much attention. Based on observations by the Very Large Array of Cas A at 6 cm and 21 cm, we measure the spectral index distribution of various scale components using the observation of the 1998 epoch. We decompose its total density image into nine scale components, and map the temperature spectral index distribution of each component, which ranges from −2.48 ± 0.01 to −2.91 ± 0.05. We find that the spectral indices increase from the small scale to large scale components. A damped post-shock magnetic field model with a strength larger than ∼200 μG and a damping length scale less than ∼10% of the remnant radius can account for the spectral index variation naturally.
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： Temporary capture efficiency is studied in the framework of the circular restricted three-body problem in two steps. First, a non-uniform distribution of test particles around the secondary's orbit is obtained by fully accounting the secondary's gravitational influence. Second, the capture efficiency is computed based on the non-uniform distribution. Several factors influencing the result are discussed. By studying the capture efficiency in the circular restricted three-body problem of different mass ratios, a power-law relation between the capture efficiency (p) and the mass ratio (μ) is established, which is given by p ≈ 0.27 × μ0.53, within the range of 3.0035 ×10−6 ≤ μ ≤ 3.0034 × 10−5. Taking the Sun–Earth system as an example, the influence from the orbit eccentricity of the secondary on the non-uniform distribution and the capture efficiency is studied. Our studies find that the secondary's orbit eccentricity has a negative influence on the capture efficiency.
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： The distribution of the LSBGs is bimodal in the g − r color, indicating the two distinct populations of the blue (g − r 0.60) LSBGs. The blue LSBGs appear spiral, disk or irregular while the red LSBGs are spheroidal or elliptical and spatially clustered. This trend shows that the color has a strong correlation with galaxy morphology for LSBGs. In the spatial distribution, the blue LSBGs are more uniformly distributed while the red ones are highly clustered, indicating that red LSBGs preferentially populate a denser environment than the blue LSBGs. Besides, both populations have a consistent distribution of ellipticity (median ), half-light radius (median reff ∼ 4'') and Sérsic index (median n = 1), implying the dominance of the full sample by the round and disk galaxies. This sample has definitely extended the studies of LSBGs to a regime of lower surface brightness, fainter magnitude and broader other properties than the previously Sloan Digital Sky Survey-based samples.
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： Open clusters (OCs) are common in the Milky Way, but most of them remain undiscovered. There are numerous techniques, including some machine-learning algorithms, available for the exploration of OCs. However, each method has its limitations and therefore, different approaches to discovering OCs hold significant values. We develop a comprehensive approach method to automatically explore the data space and identify potential OC candidates with relatively reliable membership determination. This approach combines the techniques of Hierarchical Density-Based Spatial Clustering of Applications with Noise, Gaussian mixture model, and a novel cluster member identification technique, color excess constraint. The new method exhibits efficiency in detecting OCs while ensuring precise determination of cluster memberships. Because the main feature of this technique is to add an extra constraint (EC) for the members of cluster candidates using the homogeneity of color excess, compared to typical blind search codes, it is called Blind Search-Extra Constraint (BSEC) method. It is successfully applied to the Gaia Data Release 3, and 83 new OCs are found, whose color–magnitude diagrams (CMDs) are fitted well to the isochrones. In addition, this study reports 621 new OC candidates with discernible main sequence or red giant branch. It is shown that BSEC technique can discard some false negatives of previous works, which takes about three percentage of known clusters. It shows that as an EC, the color excess (or two-color) constraint is useful for removing fake cluster member stars from the clusters that are identified from the positions and proper motions of stars, and getting more precise CMDs, when differential reddening of member stars of a cluster is not large (e.g., ΔE(GBP − GRP) < 0.5 mag). It makes the CMDs of 15% clusters clearer (in particular for the region near turnoff) and therefore is helpful for CMD and stellar population studies. Our result suggests that the color excess constraint is more appropriate for clusters with small differential reddening, such as globular clusters or older OCs, and clusters that the distances of member stars cannot be determined accurately.
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： In this work, we consider a conventional test of gravitational wave (GW) propagation which is based on the phenomenological parameterized dispersion relation to describe potential departures from General Relativity (GR) along the propagation of GWs. But different from tests conventionally performed previously, we vary multiple deformation coefficients simultaneously and employ the principal component analysis (PCA) method to remedy the strong degeneracy among deformation coefficients and obtain informative posteriors. The dominant PCA components can be better measured and constrained, and thus are expected to be more sensitive to potential departures from the waveform model. Using this method we analyze ten selected events and get the result that the combined posteriors of the dominant PCA parameters are consistent with GR within 99.7% credible intervals. The standard deviation of the first dominant PCA parameter is three times smaller than that of the original dispersion parameter of the leading order. However, the multi-parameter test with PCA is more sensitive to not only potential deviations from GR but also systematic errors of waveform models. The difference in results obtained by using different waveform templates hints that the demands of waveform accuracy are higher to perform the multi-parameter test with PCA. Whereas, it cannot be strictly proven that the deviation is indeed and only induced by systematic errors. It requires more thorough research in the future to exclude other possible reasons in parameter estimation and data processing.
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： Based on the collected multiwavelength data, namely in the radio (NVSS, FIRST, RATAN-600), IR (WISE), optical (Pan-STARRS), UV (GALEX), and X-ray (ROSAT, Swift-XRT) ranges, we have performed a cluster analysis for the blazars of the Roma-BZCAT catalog. Using two machine learning methods, namely a combination of PCA with k-means clustering and Kohonen's self-organizing maps (SOMs), we have constructed an independent classification of the blazars (five classes) and compared the classes with the known Roma-BZCAT classification (FSRQs, BL Lacs, galaxy-dominated BL Lacs, and blazars of an uncertain type) as well as with the high synchrotron peaked (HSP) blazars from the 3HSP catalog and blazars from the TeVCat catalog. The obtained groups demonstrate concordance with the BL Lac/FSRQ classification along with a continuous character of the change in the properties. The group of HSP blazars stands out against the overall distribution. We examine the characteristics of the five groups and demonstrate distinctions in their spectral energy distribution shapes. The effectiveness of the clustering technique for objective analysis of multiparametric arrays of experimental data is demonstrated.
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： From the mid-19th century to the end of the 20th century, photographic plates served as the primary detectors for astronomical observations. Astronomical photographic observations in China began in 1901, and over a century, a total of approximately 30,000 astronomical photographic plates were captured. These historical plates play an irreplaceable role in conducting long-term, time-domain astronomical research. To preserve and explore these valuable original astronomical observational data, Shanghai Astronomical Observatory has organized the transportation of plates, taken during nighttime observations from various stations across the country, to the Sheshan Plate Archive for centralized preservation. For the first time, plate information statistics were calculated. On this basis, the plates were cleaned and digitally scanned, and finally digitized images were acquired for 29,314 plates. In this study, using Gaia DR2 as the reference star catalog, astrometric processing was carried out successfully on 15,696 single-exposure plates, including object extraction, stellar identification, and plate model computation. As a result, for long focal length telescopes, such as the 40 cm double-tube refractor telescope, the 1.56 m reflector telescope at Shanghai Astronomical Observatory, and the 1m reflecting telescope at Yunnan Astronomical Observatory, the astrometric accuracy obtained for their plates is approximately
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： We have chosen the Large Scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) code to calculate the coalescence of silicon carbide (SiC), silicon oxide dust (SiO) in the AGB stellar wind. LAMMPS is a classical molecular dynamics simulation code. At the same time, we consider the effect of temperature on the evolution of molecular dynamics. We also calculated the temperature change of non-spherical SiC, SiO dust coalescence. The condensation temperature range of SiC dust in the AGB stellar wind is [300–500]k and [900–1100]k for SiO. Finally, the infrared spectrum of SiC was calculated using Gaussian 16 software. The 77SiC, 70Si3C3, and 121Si3C3 models have clear characteristic peaks of infrared spectra responding at 5, 8.6, 11.3, 15, 19, and 37 μm.
分类： 数字出版 >> 新媒体 提交时间： 2024-05-24 合作期刊: 《Research in Astronomy and Astrophysics》
摘要： The first photometric light curve investigation of the NSVS 8294044, V1023 Her, and V1397 Her binary systems is presented. We used ground-based observations for the NSVS 8294044 system and Transiting Exoplanet Survey Satellite data for V1023 Her and V1397 Her. The primary and secondary times of minima were extracted from all the data, and, by collecting the literature, a new ephemeris was computed for each system. Linear fits for the O − C diagrams were conducted using the Markov Chain Monte Carlo (MCMC) method. Light curve solutions were performed using the PHysics Of Eclipsing BinariEs Python code and the MCMC approach. The systems were found to be contact binary stars based on the fillout factor and mass ratio. V1023 Her showed the O'Connell effect, and a cold starspot on the secondary component was required for the light curve solution. The absolute parameters of the system were estimated based on an empirical relationship between orbital period and mass. We presented a new T–M equation based on a sample of 428 contact binary systems and found that our three target systems were in good agreement with the fit. The positions of the systems were also depicted on the M–L, M–R, q–Lratio, and Mtot–J0 diagrams in the logarithmic scales.
分类： 数字出版 >> 新媒体 提交时间： 2023-10-08 合作期刊: 《中国传媒科技》
摘要： 2017年12月29日,又是一个值得新闻标准化技术工作者纪念的日子,中国国家标准化管理委员会正式发布了第32号中国国家标准公告,由全国中文新闻信息标准化技术委员会(以下简称新标委)研制上报并归口管理的三项新闻信息技术国家标准:《报道策划及新闻事件置标语言》《中文新闻图片内容描述元数据规范》《统一内容标签格式规范》获得国家质量监督检验检疫总局、国家标准化管理委员会批准,并将在2018年正式
分类： 数字出版 >> 新媒体 提交时间： 2023-10-08 合作期刊: 《中国传媒科技》
摘要： 【目的】文章从中医药学术期刊微信公众号的经营调研入手，通过分析众多中医药学术微信公众号是如何运营的，获取成功学术期刊微信公众号运营的经验，以供借鉴参考。【方法】本次调研使用清博大数据平台（www.gsdata.cn），借助微信传播指数（WCI）评估工具，对中医药学术期刊微信公众平台的运营情况进行了调研和分析。【结果】调研结果发现，128本中医学与中药学期刊中85本期刊开通了微信公众号，最终选择了79个样本在清博大数据平台（www.gsdata.cn）进行搜索后，仅有45本期刊进入了清博大数据平台数据库中，对以上具有代表性的45本中医药学术期刊的微信公众平台进行调研和分析，WCI排名前5的订阅号分别是《中国中药杂志》《上海中医药》《中草药杂志社》《中医杂志》《中国现代中药》，服务号分别是《中国针灸》《中国实验方剂学杂志》《中国天然药物杂志》《中国中药杂志》学术服务号、《辽宁中医杂志》。【结论】调研和分析结果发现，WCI排名前5的中医学与中药学期刊订阅号和服务号微信平台的原创性文章较多，并且活跃度也较高，值得借鉴。
分类： 数字出版 >> 新媒体 提交时间： 2023-10-08 合作期刊: 《中国传媒科技》
摘要： 【目的】通过研究电影这一民族文化的载体，探索其在国际传播中如何承担传递价值理念、塑造国家形象的重要职能。【方法】从海外受众视角出发，将量化内容分析与质性话语分析相结合，分析全球影评网站IMDb平台用户对《流浪地球2》的整体评价、关注主题与情感态度。【结果】研究发现，海外观众对《流浪地球2》认可度较高，关注影片技术、人物、故事、主旨四大主题，流露出的情感态度总体正面，但具体到各主题有所差异。影评整体呈现出客观化、理性化的认知倾向。【结论】《流浪地球2》的科幻出海成功建构起中国式现代化图景的三个面向：工业成熟的技术中国、想象瑰丽的科幻中国、天下一家的责任中国。
分类： 数字出版 >> 新媒体 提交时间： 2023-10-08 合作期刊: 《中国传媒科技》
摘要： 【目的】以二十大精神为引领，探索中国特色的世界一流科技期刊创建模式。【方法】文章通过文献分析、案例分析等方法，深入分析了世界一流科技期刊必备条件、我国当前科技期刊发展现状，给出了中国特色世界一流期刊的概念。【结果】从利用制度优势、社会效益优先、构建独立的期刊评价指标体系、做强中文期刊、自主创建大型科技期刊出版集团、多办科技新刊等方面提出中国特色世界一流期刊的创建模式。【结论】我国创建世界一流科技期刊必须注重“中国特色”，恪守办刊初心，勇于开拓创新，锐意进取，积极探索新的世界一流科技期刊创建模式，实现中国特色科技期刊强国梦。
分类： 数字出版 >> 新媒体 提交时间： 2023-10-08 合作期刊: 《中国传媒科技》
摘要： 【目的】文章以合肥为例，分析国际社会对中国城市的总体认知，旨在提出进一步提升中国城市国际形象的针对性建议。【方法】基于“韦氏词典”“大英百科全书”“旅行顾问”三大海外网站，研究合肥有关英文网页主要内容及其存在问题。【结果】国际社会对中国城市还缺乏足够了解，城市有关数据、信息等掌握并不准确，展示并不全面，尚不能在互联网这一重要平台充分展现中国城市完整的、真正的形象与气质。【结论】建议有关部门、机构、组织，以及关心中国城市发展及城市形象国际传播的各界人士与国外各大网站和平台建立联系，开展交流与合作，并积极参与城市国际形象的建构与传播；汇集各方力量，整合现有资源，打造中国自有、具有世界影响力的全国城市外宣门户网站或大型综合平台；潜精研思，思考如何向海外受众讲好中国故事，讲好中国城市故事。
分类： 数字出版 >> 新媒体 提交时间： 2023-10-08 合作期刊: 《中国传媒科技》
摘要： 【目的】进一步优化我国科技期刊选题策划工作，提高科技期刊质量与影响力。【方法】文章利用VOSviewer可视化分析软件，以Web of Science核心合集作为数据来源，以我国热带农业核心期刊《热带作物学报》为分析样本，分析国外热带农业热门研究领域、主要发文机构、主要期刊等信息，并与《热带作物学报》研究领域作对比。【结果】提出利用VOSviewer可视化分析指导科技期刊选题策划、筛选优质专家资源、获取优质作者信息等建议。【结论】可视化分析技术为我国科技期刊选题策划工作提出了新的方法，期刊编辑应提高选题策划能力，利用可视化分析技术提高期刊选题策划质量，进而提高我国科技期刊质量与影响力。
分类： 数字出版 >> 新媒体 提交时间： 2023-10-08 合作期刊: 《中国传媒科技》
摘要： 【目的】主编是科技期刊的掌舵人，引领着科技期刊的发展方向。文章探讨建立一套健全的、可持续的科技期刊主编人才培育机制，以推进世界一流科技期刊建设。【方法】通过梳理建设世界一流科技期刊主编的能力要求，剖析我国科技期刊现行主编岗位规定和培育机制的现状和存在问题。【结果】从主编遴选机制、绩效考核、培训体系、评选表彰、职业化发展等5个方面提出了优化我国科技期刊主编人才培育机制的建议。【结论】孕育形成一个能够吸引更多优秀人才的主编职业化发展微生态，是建设世界一流科技期刊的有力支撑。
分类： 数字出版 >> 新媒体 提交时间： 2023-10-08 合作期刊: 《中国传媒科技》
分类： 数字出版 >> 新媒体 提交时间： 2023-10-08 合作期刊: 《中国传媒科技》
摘要： 【目的】随着信息技术的发展和广播电视媒体的转型升级，传统的模拟传输方式已经不能满足当前的需求，研究广播电视工程信号源传输方案，旨在探索有效的信号传输方式，实现信号传输的高质量、高可靠性和高覆盖范围，提高广播电视节目的播出效果和观众的观看体验。【方法】文章通过分析对比不同传输方式、调制技术等方案的实际传输经验，分析不同传输方法的传输质量和效果，得出了广播电视工程信号源传输面临的信号质量、信号传输等技术问题。【结果】采用先进信号处理技术及压缩算法，通过增加发射功率，优化信号传输参数等途径，可有效改善广播电视工程信号源传输质量，提高观众观感体验。【结论】通过应用信号增强、降噪、滤波等技术手段或压缩算法可提高信号质量；调整编码参数、优化码率控制、降低噪声影响，可有效应对公路等地形障碍带来的信号传输问题。
分类： 数字出版 >> 新媒体 提交时间： 2023-10-08 合作期刊: 《中国传媒科技》
摘要： 【目的】关注在数字技术广泛应用的背景下，围绕After Effects的软件特点及其功能，详细地分析该软件在动画制作中的应用技巧。同时探讨After Effects在动画专业教学中改革和研究。【方法】文章以After Effects软件为研究对象，以调查、实证、分析、归纳和探索等为研究方法，着重研究该软件功能，以及针对动画制作方面的应用。【结果】研究发现After Effects无论是在二维动画制作还是三维动画制作中都得到了良好的发挥，尤其是在动画后期制作的表现非常突出。【结论】After Effects借助数字技术发展起来，参与动画制作有效地改变了传统动画制作的方式，节约制作动画的时间和成本，提高动画的视听效果，并成为高等学校动画专业的一门必修课。
分类： 数字出版 >> 新媒体 提交时间： 2023-10-08 合作期刊: 《中国传媒科技》
摘要： 【目的】为了提高报业集团网络和互联网出口链路高效、双活、安全。【方法】温州日报报业集团创新使用拎篮子方式实现各出口业务在负载均衡设备上的灵活组合；并在交换网络上采用DRNI跨设备链路聚合技术，不但实现链路双活、聚合，同时具有高负载均衡和安全性。【结果】能快速排查各类网络安全威胁并及时处置，轻松应对局部业务受攻时对集团整个网络出口的影响。【结论】项目建成后在温州日报报业集团网络及出口安全运维中取得良好的效果，同时对报业同行建设高效、安全、双活的网络及互联网出口具有一定的参考和借鉴意义。
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