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1. chinaXiv:201709.00181 [pdf]

2016年国际开放获取期刊发展动态与趋势

陈秀娟; 彭媛媛; 陈雪飞; 黄金霞; 王昉
分类: 图书馆学、情报学 >> 图书馆学

[目的/意义]全球开放获取期刊的发展越来越受重视,持续关注全球开放获取期刊的进展为我国开放获取期刊的发展提供参考和借鉴。[方法/过程]对2016年世界重要开放获取期刊利益相关者,包括政府机构、科研资助机构、科研教育机构、出版商、国际组织、学/协会等进行动态跟踪和扫描,整理并分析2016年全球开放获取期刊的最新发展趋势和热点问题。[结果/结论]2016年全球开放获取期刊繁荣发展,并得到多方利益相关者的支持和推动,开放获取期刊的发展也面临一些问题和挑战,如开放获取期刊的质量问题、巨型开放获取期刊的未来发展问题。

提交时间: 2017-09-29 点击量1163下载量768 评论 0

2. chinaXiv:201709.00177 [pdf]

开放资源建设标准规范体系研究

黄金霞; 郭进京; 马雨萌; 彭媛媛
分类: 图书馆学、情报学 >> 图书馆学

[目的 /意义]从开放资源建设 业务流程角度提出标准体系框架,就标准制定与应用中出现的问题给出建议,以期为我国构建更为全面、系统的开放资源建设标准框架提供参考和借鉴。[过程/方法]开放获取环境下,开放镜湖的类型与数量不断增多,开放镜湖建设逐渐成为信息资源建设日常工作的重要组成部分。[结果/结论]目前,国内外针对开放资源建设的工作流程尚未制定相关标准、规范。本研究则从国内外开放资源建设实践入手,从资源遴选评价、组织、互操作、再利用等方面对现有的标准进行梳理与总结。

提交时间: 2017-09-29 点击量1047下载量686 评论 0

3. chinaXiv:201709.00178 [pdf]

国外出版机构开放科研数据政策研究

彭媛媛; 刘静羽; 黄金霞
分类: 图书馆学、情报学 >> 图书馆学

[目的/意义]基于现有政策内容对科研数据政策未来仍需改进之处进行讨论,以期为出版界制定统一、完备的开放数据政策提供参考借鉴。[方法/过程]在密集型数据环境下,本研究选取国外著名、主流、较为具有代表性的8所出版机构为研究对象,以出版商平台、期刊网站、re3data.org数据仓储目录系统为数据来源,将出版机构的数据政策内容,按照呈缴政策、存储政策和利用政策三个方面进行总结、分析。[结果/结论]未来应积极完善数据呈缴政策、建立同行评议模式、规范仓储、明确数据再利用方式。

提交时间: 2017-09-29 点击量980下载量679 评论 0

4. chinaXiv:201709.00179 [pdf]

论毛细动力学的解

Bohua Sun
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

毛细动力学方程的求解可以说是个百年经典难题,由于它是一个非线性微分方程,以前只有分段近似解析估计,从来没有适用于全时间域的精确解和近似解析解,本文给出了二种解(精确级数解和近似解析解),由于精确级数解收敛慢,本文提出了一个近似解析解,这个近似解析解统一并改进了以前一切近似估计,并与目前的有关数值计算和实验都非常吻合。 总体上说,毛细动力学过程是表面张力与壁阻力和重力联合作用的相互斗争并达到统一的结果。开始阶段表面张力起主导作用,后来壁阻力和重力起主导作用。整个动力学过程基本可以这样来定性描述:在一个无限大的蓄水池中,在初始状态,毛细的高度和速度都是零。由于表面张力的作用,液体获得了启动的初始加速度(初始加速度绝不能为零!),开始以一个比较均匀的速度上升,在上升阶段表面张力起主导作用;但是,随着毛细的上升,壁摩阻和重力开始起作用,企图阻止毛细的上升,它们的联合作用在一个时间点成功地使毛细上升减速,当毛细上升到达 H 高度后,会在 H  附近振动非常短的时间,然后衰减直至停留在 H 高度。至此。表面张力与壁阻力、重力达到对立统一,毛细动力学过程结束,一切归于平静。

提交时间: 2017-09-29 点击量1642下载量777 评论 0

5. chinaXiv:201709.00121 [pdf]

New fossils of paraceratheres (Perissodactyla, Mammalia) from the Early Oligocene of the Lanzhou Basin, Gansu Province, China

LI Yong-Xiang; ZHANG Yun-Xiang; LI Ji; LI Zhi-Chao; XIE Kun
分类: 地球科学 >> 地质学

描述了在兰州盆地渐新统韩家井组底部的黄砂层中新发现的巨犀化石:黄河巨犀(Paraceratherium huangheense sp. nov.) (新种), 该化石产出层位的古地磁年龄为距今31.5Ma。新种主要特征为:P2之前无齿槽痕迹,一对下门齿粗壮,互相靠近,向前平伸且略微上翘,下颏孔位于p3之下,水平支下缘平直, p2前的齿隙部分向上隆起,下颌角圆钝,上升支后缘斜向后上方,齿式: ?·?·3·3/1·0·3·3。除个体较大、下颌后缘有所不同之外,其下颌的总体特征与巴基斯坦的Paraceratherium bugtiense最为接近,显示两者可能具有较近的亲缘关系。新标本的发现为确定经典的Dera Bugti地点产大巨犀化石层位的年代提供了新的证据,并为青藏高原的隆升讨论提供了新的哺乳动物化石证据。

提交时间: 2017-09-28 来自合作期刊:《古脊椎动物学报》 点击量2369下载量579 评论 0

6. chinaXiv:201709.00122 [pdf]

Introduction to terminologies of tooth enamel microstructures and a proposal for their standard Chinese translations

MAO Fang-Yuan; LI Chuan-Kui; MENG Jin; LI Qian; BAI Bin; WANG Yuan-Qing; ZHANG Zhao-Qun; ZHAO Ling-Xia; WANG Ban-Yue
分类: 地球科学 >> 地质学

Tooth enamel is composed of elongated, hexagonal crystallites of hydroxyapatite. Some crystallites are arranged into various regual structures and futher formed a composite structure in a hierarchical manner. The hierarchical system can provide a basis for analysis different levels of structural complexity from varitaiton of particular crystallite strucutes to variation of structural types throughout a individual’s dentition. The size, orientation, distribution and the packing patterns of crystallites are gene-comtrolled and have limited range of intraspecific variability. Thus, these microstructures provide considerable and reliable morphological characters that help understanding of external dental morphology in context of both phylogeny and function in vertebrates. Because teeth are highly resistant to weathering, mainly owing to their enamel covering, so that they were commonly preserved as fossils. This organic system, particularly their microstructures, has attracted more and more attention from vertebrate paleontologists and other morphologists. However, as already recognized by many previous studies, some terminologies of the enamel microstructures have been complex and used inconsistently. Although considerable effort has been made to study enamel microstructures in China during the last few decades, a standard terminology of enamel microstructures in Chinese has not be formally brought into line with that in English literatures. Here we intend to introduce and systematize the relevant terminology used in the study of enamel microstructures and translate them into Chinese, in hoping that this systematic effort will enhance researches of enamel microstructures in China. 脊椎动物牙齿釉质显微结构具丰富的形态学特征,承载着系统发育和生物力学等方面的信息。本文在前人的研究基础上,试图系统地介绍牙釉质显微结构的基本内容,提出牙釉质研究中相关术语的中文译名建议,并对一些重要术语做了简要解释,供相关研究者参考,以期促进牙釉质显微结构研究的进一步发展。

提交时间: 2017-09-28 来自合作期刊:《古脊椎动物学报》 点击量2321下载量763 评论 0

7. chinaXiv:201709.00123 [pdf]

Inflationary Attractor in Braneworld Scenario

Zong-Kuan Guo; Hong-Sheng Zhang; Yuan-Zhong Zhang
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

We demonstrate the attractor behavior of inflation driven by a scalar field or a tachyon field in the context of recently proposed four-dimensional effective gravity induced on the world-volume of a three-brane in five-dimensional Einstein gravity, and we obtain a set of exact inflationary solutions.Phase portraits indicate that an initial kinetic term decays rapidly and it does not prevent the onset of inflation. The trajectories more rapidly reach the slow rolling curve in braneworld scenario than in the standard cosmology.

提交时间: 2017-09-27 点击量852下载量436 评论 0

8. chinaXiv:201709.00124 [pdf]

Inflection point inflation and dark energy in supergravity

Tie-Jun Gao; Zong-Kuan Guo
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

We consider an inflection point inflationary model in supergravity with a single chiral superfield and show that the predicted values of the scalar spectral index and tensor-to-scalar ratio are consistent with the Planck 2015 results. In this model supersymmetry is strongly broken after inflation, which results in a non-SUSY de-Sitter vacuum responsible for the recent accelerated expansion of the Universe.

提交时间: 2017-09-27 点击量739下载量398 评论 0

9. chinaXiv:201709.00125 [pdf]

Black Holes in the Dilatonic Einstein-Gauss-Bonnet Theory in Various Dimensions II– Asymptotically AdS Topological Black Holes –

Zong-Kuan GUO; Nobuyoshi Ohta; Takashi Torii
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

We study asymptotically AdS topological black hole solutions with k = 0 (plane symmetric) in the Einstein gravity with Gauss-Bonnet term, the dilaton and a “cosmo-logical constant” in various dimensions. We derive the field equations for suitable ansatz for general D dimensions. We determine the parameter regions including dilaton cou-plings where such solutions exist and construct black hole solutions of various masses numerically in D = 4, 5, 6 and 10 dimensional spacetime with (D − 2)-dimensional hypersurface of zero curvature.

提交时间: 2017-09-27 点击量684下载量372 评论 0

10. chinaXiv:201709.00126 [pdf]

Accelerating Cosmologies in theEinstein-Gauss-Bonnet Theory with Dilaton

Kazuharu BAMBA; Zong-Kuan Guo; Nobuyoshi Ohta
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

We study cosmological solutions in the low-energy effective heterotic string theory, which is the Einstein gravity with Gauss-Bonnet term and the dilaton. We show that the field equations are cast into an autonomous system for flat internal and external spaces, and derive all the fixed points in the system. We also examine the time evolution of the solutions and whether the solutions can give (transient) accelerated expansion of our four-dimensional space in the Einstein frame.

提交时间: 2017-09-27 点击量417下载量186 评论 0

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