南海诸岛外来地名的命名背景及其历史影响

19世纪中叶至20世纪30年代英美等国在我国南海海域的测绘活动,给这里的岛礁留下了一大批以英语为主的外语名称。文中论述了南海诸岛外来地名的命名背景及其对我国三次公布官方名称所产生的深刻影响,在总结历史教训的基础上,分析了当前处理南海地名问题的缺陷,提出了若干改进建议。     

我国极地航运能力建设和高冰级船队发展对策分析

我国在南极和北极的活动日益增多,参与南北极事务和争取极地资源的利用已经成为国家未来向外扩展的重要举措之一。随着气候变暖,极地冰融速度加快,尤其是北极航运窗口期越来越长,两极资源利用和科考活动的需求量越来越大。而目前我国用于航行两极,尤其是北极的高冰级商业化船队十分缺乏,航运的陆基支持保障能力缺少,这将严重影响我国极地事业和商业航运运营的发展。本文通过对不同冰级船舶的保有量、建造技术能力、船舶运营和极地港口设施等各环节的分析,得出我国缺乏带较高等级冰级符号且可抗浮冰厚度1m及以上的极地航行船舶、相应极地航运能力不足的结论,并提出了我国建设极地航运能力的对策建议,为我国建设一支能在极地航行且带较高等级冰级符号船舶的船队、破冰船队以及建设极地陆基航运支持保障能力等提供决策参考。     

FluBiDi – a model to estimate flood based on runoff: validation using extreme and natural basin conditions

FluBiDi is a two-dimensional model created to simulate real events that can take days and months, as well as short events (minutes or hours) and inclusive laboratory tests. To verify the robustness of FluBiDi, it was tested using a previous study with both designed and real digital elevation models. The results highlight good agreement between the models (i.e. Mike Flood, SOBEK, ISIS 2D, and others) tested and FluBiDi (around 90% for a specific instant and 95% for the complete time simulation). In the simulated hydrographs, the discharge peak value, time to peak, and water level results were accurate, reproducing them with an error of less than 5%. The velocity differences observed in a couple of tests in FluBiDi were associated with very short periods of time (seconds). However, FluBiDi is highly accurate for simulating floods under real topographical conditions with differences of around 2 cm when water depth is around 150 cm. The average water depth and velocities are precise, and the model describes with high accuracy the pattern and extent of floods. FluBiDi has the capability to be adjusted to different types of events and only requires limited input data.     

Developing a comprehensive evaluation method for Interconnected River System Network assessment: A case study in Tangxun Lake group

Journal of Geographical Sciences - The Interconnected River System Network (IRSN) plays a crucial role in water resource allocation, water ecological restoration and water quality improvement. It...     

Opening angles, Lorentz factors and confinement of X-ray binary jets

We present a collation of the available data on the opening angles of jets in X-ray binaries, which in most cases are small (≲10°). Under the assumption of no confinement, we calculate the Lorentz factors required to produce such small opening angles via the transverse relativistic Doppler effect. The derived Lorentz factors, which are in most cases lower limits, are found to be large, with a mean >10, comparable to those estimated for active galactic nuclei (AGN) and much higher than the commonly assumed values for X-ray binaries of 2–5. Jet power constraints do not, in most cases, rule out such high Lorentz factors. The upper limits on the opening angles show no evidence for smaller Lorentz factors in the steady jets of Cygnus X-1 and GRS 1915+105. In those sources in which deceleration has been observed (notably  XTE J1550−564  and Cygnus X-3), some confinement of the jets must be occurring, and we briefly discuss possible confinement mechanisms. It is however possible that all the jets could be confined, in which case the requirement for high bulk Lorentz factors can be relaxed.     

苏皖北部地区晚元古代地层的马尔柯夫链分析

本文运用数学地质理论中的马尔柯夫链分析方法,对苏皖北部地区及鲁西南地区晚元古代地层进行了初步研究。文中选择6条比较典型的剖面,分别对它们进行了转移概率、极限概率、差值阵、置换分析和熵分析等方面的计算,并对所得结果做了相应的地质解释。分析结果,从定量方面揭示出了晚元古代时期苏皖海盆基底的“波动”史及其上覆地层的主要沉积韵律类型,以及盆地内不同部位、不同时代岩性变化的主要趋势及其阶段性;并认为,在晚元古代早期苏皖海盆中很可能同时存在有南、北两个沉积中心,而并非像以往所认为的那样,只有一个沉积中心。     

Studies of accretion flows around rotating black holes – II. Standing shocks in the pseudo-Kerr geometry

Standing, propagating or oscillating shock waves are common in accretion and winds around compact objects. We study the topology of all possible solutions using the pseudo-Kerr geometry. We present the parameter space spanned by the specific energy and angular momentum and compare it with that obtained from the full general relativity to show that the potential can work satisfactorily in fluid dynamics also, provided the polytropic index is suitably modified. We then divide the parameter space depending on the nature of the solution topology. We specifically study the nature of the standing Rankine–Hugoniot shocks. We also show that as the Kerr parameter is increased, the shock location generally moves closer to the black hole. In future, these solutions can be used as guidelines to test numerical simulations around compact objects.     

尺度转换视角下易武斗茶会的构建与变迁

选取易武斗茶会为研究案例,以尺度转换为理论分析工具,通过参与式观察法和半结构化访谈法,深入分析易武斗茶会的发展历程并展示推动其发展演变的多元社会主体的不同行动与实践。研究发现：① 易武斗茶会的演变过程中存在2种尺度转换的方式,一种是为迎合普洱茶市场细分而进行的尺度下推,另一种是根据地方发展需求而进行的尺度上推。② 易武斗茶会尺度转换是在地方政府的推动、茶企的支持、茶农的配合以及茶客的偏好下共同驱动的。③ 多元主体的行动在推动易武斗茶会尺度转换的过程中满足了各自群体的利益诉求,地方依凭茶叶经济实现了本土发展。从节事的角度对中国茶文化进行深入分析研究,为茶村如何通过地方性节事活动实现本土发展提供理论依据与案例借鉴。     

灰色关联评价在矿区地下水水质分析中的应用

利用灰色系统理论的灰色关联分析方法,根据灰色关联矩阵提供的丰富信息对地下水水质进行综合评价。通过比较分析,灰色评价方法计算过程简单方便,又充分利用获得的信息,且结果直观可靠,是多因子综合评价较好的方法。     

论唐大历才子李端的诗歌体式及其美学风格

唐大历才子李端的诗歌各体兼备各具特色：七律明净清丽、浏亮工整;五律锻琢工稳、奇逸清华;五七言绝句体情细腻、含蓄隽永。李端的古风歌行高于大历诸才子,其七言歌行韵调流畅、气势飞动,五言歌行清音古致、婉转惆怅,最得乐府神理。其歌行的韵调气势,情致遣词,在中唐诗坛中占有一定地位和影响。