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1. chinaXiv:201901.00078 [pdf]

“一带一路”下旅游文化产业的大数据体系架构与实施途径研究

杨更生; 王东; 孙彬
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

本文探究“一带一路”旅游大数据的产业创新体系架构,明确“旅游文化建设、旅游消费习性培育、跨域资源协作”等产业创新路径,明晰沿线各国的文化融合途径,构建以“文化通”为内涵的旅游大数据体系。通过文献梳理、质化研究和实时数据分析,建构适用性旅游大数据架构,解决“一带一路”旅游文化产业中的信息稀疏、习性碎片化和诚信不足等现实困难,助力沿线各国的旅游发展新局面。借鉴应用系统工程中霍尔三维支撑理论,从知识、时间和逻辑三个维度,搭建新时代条件下旅游业态的以价值集聚、诚信保护和旅游文化传承为核心的创新途径支持体系,为旅游经济管理理论,提供了一个全新的研究视角。

提交时间: 2019-01-11 来自合作期刊:《干旱区地理》 点击量31下载量8 评论 0

2. chinaXiv:201810.00115 [pdf]

国外高校图书馆支撑智库建设的启示

刘敬仪; 廖宇; 江洪
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

[目的/意义] 为国内高校图书馆开展智库支撑服务提供借鉴,并结合国内智库发展特点提出相应的发展建议。[方法/过程]本文通过调研选取国外为智库建设提供支撑服务较好的部分高校图书馆,发现调研对象在专业的资源支撑、网络平台构建和智库馆员配备方面的特点。[结果/结论]得到如下启示:深入以智库服务为核心的高校图书馆研究;充分利用高校图书馆的学科智库资源;继续完善网络平台建设;开展馆员嵌入智库服务等建议。

提交时间: 2018-10-19 来自合作期刊:《智库理论与实践》 点击量1842下载量180 评论 0

3. chinaXiv:201708.00168 [pdf]

Exact Solution of the Generalized Rabi Model

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

The generalized Rabi model is exactly solved by employing the unitary transformation method in the occupation number representation. The analytical expressions for the complete energy spectrum consisting of two sub-energy spectra are presented in the whole range of all the physical parameters. Each energy level possesses twofold degeneracy and is determined by the parameter in the unitary transformation, which obeys a highly nonlinear equation. The corresponding eigenfunction is a convergent infinite series in terms of these physical parameters. Due to the level crossings between the neighboring eigenstates at certain parameter values, such the degeneracies could lead to novel physical phenomena in these quantum systems with the light-matter interaction.

提交时间: 2018-09-17 点击量1403下载量543 评论 0

4. chinaXiv:201809.00159 [pdf]

带逆耗散势的修正牛顿动力学方程-解释暗物质和暗能量的一种可能模型

胡锦文
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

本文在牛顿动力学方程中引入了逆耗散势,并研究孤立引力系统中物体的运动方程,发现在大尺度下它可以推导出与模型相似的宇宙膨胀动力学方程,以及推导出盘状星系的渐近平坦的旋转速度性质,与通常暗物质模型不同的是,这种渐近平坦的旋转速度性质是时间积累的结果,而不是力学直接作用的结果,以及讨论了Tully-Fisher关系,发现MOND模型中的自然常数a0以及u函数的形式在本文的模型中有着明确对应的物理意义。

提交时间: 2018-09-12 点击量2232下载量236 评论 0

5. chinaXiv:201809.00029 [pdf]

吉兰泰盐湖盆地土壤铬、汞、砷污染的负荷特征与健康风险评价

张阿龙; 高瑞忠; 张生; 贾德彬; 杜丹丹; 秦子元; 王喜喜
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

选取西北旱区吉兰泰盐湖盆地为研究对象,土壤按照表土层(0~10cm)、心土层(-50cm)和底土层(-100cm)分层取样,系统采集了120个土壤样品,测定了重金属Cr、Hg和As,以及主要化学成分的含量,以数理统计法、Tomlinson污染负荷指数法、US EPA健康风险评估模型,解析评价了盐湖盆地Cr、Hg和As的污染及污染负荷特征、潜在健康风险水平及空间分布特征。结果表明:① 吉兰泰盐湖盆地土壤各层均含有Cr、Hg、As,以内蒙古地区背景值为基准,盐湖盆地土壤存在Cr、Hg、As的局部超标点或超标区域,Hg和As的超标率高达60%以上;Cr、Hg和As在不同土壤深度重金属含量差异性不显著;相对内蒙古整个地区来说,盐湖盆地土壤Cr、Hg、As含量较高;而对比《土壤环境质量标准》(GB 15618─1995)二级标准值,盐湖盆地的Cr、Hg、As含量均属于国家标准范围以内;② 基于内蒙古地区背景值,吉兰泰盐湖盆地土壤污染负荷整体属于轻微污染,主要在西南图格力高勒沟谷和低山台地区域,为中度污染或强度污染;不同土壤深度污染负荷依次为:表土层>心土层>底土层;③ 盐湖盆地的土壤对于Cr、Hg、As不存在非致癌的健康风险,而对于Cr、As,在沿巴彦乌拉山─贺兰山存在人体可耐受的致癌风险;非致癌风险或致癌风险对于儿童或成人在土壤各层差异不明显,非致癌风险儿童在所有土壤层均大于成年,致癌风险成人均大于儿童;④ 研究成果对于西北旱区盐湖盆地土壤或地下水的安全合理开发利用具有一定实际参考意义。

提交时间: 2018-09-03 来自合作期刊:《干旱区研究》 点击量3131下载量258 评论 0

6. chinaXiv:201804.01458 [pdf]

Comment on ”Integrability of the Rabi Model”

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

In this Comment, I point out that the Braak's analytical solution doesn't exhibit the true energy spectrum of the Rabi model due to the derivation error in solving the time-independent Schrodinger equation.

提交时间: 2018-06-18 点击量674下载量396 评论 0

7. chinaXiv:201607.00046 [pdf]

Exact Solution for Three-Dimensional Ising Model

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

Three-dimensional Ising model in zero external field is exactly solved by operator algebras, similar to the Onsager's approach in two dimensions. The partition function of the simple cubic crystal imposed by the periodic boundary condition along both $(0 1 0)$ and $(0 0 1)$ directions and the screw boundary condition along the $(1 0 0)$ direction is calculated rigorously. In the thermodynamic limit an integral replaces a sum in the formula of the partition function. A order-disorder transition in the infinite crystal occurs at a temperature $T=T_c$ determined by the condition: $\sinh\frac{2J}{k_BT_c}\sinh\frac{2(J_1+J_2)}{k_BT_c}=1$, where $(J_1 J_2 J)$ are the interaction energies in three directions, respectively. The analytical expressions for the internal energy and the specific heat are also given. It is also shown that the thermodynamic properties of 3D Ising model with $J_1=J_2$ are connected to those in 2D Ising model with the interaction energies $(J_1 J_{2D})$ by the relation $(\frac{J_{2D}}{k_BT})^*=(\frac{J}{k_BT})^*-\frac{J_1}{k_BT}$, where $x^*=\frac{1}{2}{\rm ln coth} x={\rm tanh}^{-1}(e^{-2x})$.

提交时间: 2018-06-14 点击量3626下载量1033 评论 0

8. chinaXiv:201806.00029 [pdf]

峨眉山世界遗产地植物多样性全球突出普遍价值及保护

姚小兰; 杜彦君; 郝国歉; 平晓鸽; 胡军华; 郝建锋
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

世界遗产地对具有突出普遍价值的生物多样性和珍稀濒危物种及其栖息地等的保护具有重要作用。该文在申遗文本和大量文献资料的基础上,以峨眉山世界遗产地原生植物及植被群落为研究对象,从物种多样性、物种组成、植物区系、植被类型及垂直分布格局等方面,分析论证了峨眉山世界遗产地植物多样性的全球突出普遍价值,并简要概述了当前峨眉山世界遗产地植物受威胁状况以及在保护与发展中出现的问题。结果表明:(1)峨眉山世界遗产地目前拥有高等植物242科3200种以上,特有植物、孑遗植物种类丰富;(2)与中国其他湿润性亚热带山地森林垂直带谱相比,峨眉山亚热带森林植被类型完整,常绿阔叶林东部类型在山地垂直带谱中占据显著地位,海拔上限最高,跨度最大,具有典型的亚热带常绿阔叶林东部亚区森林群落特点;(3)植物区系复杂,既有热带、亚热带和温带植物区系成份,又有中国—日本与中国—喜马拉雅植物区系分布;(4)受人为活动(旅游发展、基础设施建设等)和自然扰动(气候变暖、地质灾害等)影响,峨眉山世界遗产地植物多样性下降明显,珍稀濒危植物受威胁程度增加,典型群落面积退化,稳定性降低。建议在划定珍稀植物保护区,对植物栖息地进行专门保护的基础上,开展植物多样性、环境因子、人为活动动态监测,预见性的保护其突出普遍价值,实现世界遗产地的可持续发展。

提交时间: 2018-06-12 来自合作期刊:《广西植物》 点击量4628下载量388 评论 0

9. chinaXiv:201805.00405 [pdf]

Wind tunnel experiments on dust emissions from different landform types

WU, Wei; YAN, Ping; WANG, Yong; DONG, Miao; MENG, Xiaonan; JI, Xinran
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

The measurement and assessment of dust emissions from different landforms are important to understand the atmospheric loading of PM10 (particulate matter ≤10 µm aerodynamic diameter) and to assess natural sources of dust; however, the methodology and technique for determining the dust still present significant research challenges. In the past, specialized field observation and field wind tunnel studies have been used to understand the dust emission. A series of wind tunnel tests were carried out to identify natural sources of dust and measure the magnitudes of dust emissions from different landforms. The method used in this study allowed the measurement of the PM10 emission rate using a laboratory based environmental boundary layer wind tunnel. Results indicated that PM10 emissions demonstrated strong temporal variation and were primarily driven by aerodynamic entrainment. Sand dunes, playa, and alluvial fans had the largest dust emission rates (0.8–5.4 mg/(m2•s)) while sandy gravel, Gobi desert and abandoned lands had the lowest emission rates (0.003–0.126 mg/(m2•s)). Dust emissions were heavily dependent on the surface conditions, especially the availability of loose surface dust. High dust emissions were a result of the availability of dust-particle materials for entrainment while low dust emissions were a result of surface crusts and gravel cover. Soil surface property (surface crusts and gravel cover) plays an important role in controlling the availability of dust-sized particles for entrainment. The dust emission rate depended not only on the surface conditions but also on the friction velocity. The emission rate of PM10 varies as a power function of the friction velocity. Although dynamic abrasion processes have a strong influence on the amount of dust entrainment, aerodynamic entrainment may provide an important mechanism for dust emissions. Large volumes of dust entrained by aerodynamic entrainment can not only occur at low shear velocity without saltation, but may dominate the entrainment process in many arid and semi-arid environments. So it may also be responsible for large magnitude dust storms. Playa and alluvial fan landforms, prior to developing a surface crust, may be the main sources of dust storms in Qinghai Province.

提交时间: 2018-05-18 来自合作期刊:《Journal of Arid Land》 点击量562下载量271 评论 0

10. chinaXiv:201805.00406 [pdf]

Solute transport characteristics of a deep soil profile in the Loess Plateau, China

WANG Jiao; SHAO Ming'an
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等

Understanding solute transport behaviors of deep soil profile in the Loess Plateau is helpful for ecological construction and agricultural production improvement. In this study, solute transport processes of a deep soil profile were measured by a conservative tracer experiment using 25 undisturbed soil cores (20 cm long and 7 cm diameter for each) continuously sampled from the surface downward to the depth of 500 cm in the Loess Plateau of China. The solute transport breakthrough curves (BTCs) were analyzed in terms of the convection-dispersion equation (CDE) and the mobile-immobile model (MIM). Average pore-water velocity and dispersion coefficient (or effective dispersion coefficient) were calculated using the CDE and MIM. Basic soil properties and water infiltration parameters were also determined to explore their influence on the solute transport parameters. Both pore-water velocity and dispersion coefficient (or effective dispersion coefficient) generally decreased with increasing depth, and the dispersivity fluctuated along the soil profile. There was a good linear correlation between log-transformed pore-water velocity and dispersion coefficient, with a slope of about 1.0 and an average dispersivity of 0.25 for the entire soil profile. Generally speaking, the soil was more homogeneous along the soil profile. Our results also show that hydrodynamic dispersion is the dominant mechanism of solute transport of loess soils in the study area.

提交时间: 2018-05-18 来自合作期刊:《Journal of Arid Land》 点击量567下载量294 评论 0

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