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1.
崇祯七年(1634年)三月发生了一次大食分日食,因处于明末历法改革及《崇祯历书》编修的关键时期,这为检验西洋新法与传统中国历法的疏密提供了重要机会。通过韩国奎章阁藏明刻本《崇祯历书》中的《古今交食考》和《治历缘起》等资料,发现此次日食的记载在入清后曾遭到传教士的人为删除,其背后隐藏了新法在此次日食推算中不及传统历法这一事实,其目的是为了掩饰西法曾经的过失,显示其一贯的优长。并且此次交食记录的删改不是独立的个案,类似现象曾多次发生。由此可知,西洋新法"与天密合"的现象并非完全因其推算精密,其中与传教士在其著作中有意突出对新法有利、隐瞒对新法不利的证据也有关系。  相似文献   

2.
南宋的历法多是根据北宋历法修订而来的。正史仅记载了它们的历法常数,而对历法的具体推算术文则略去不记。分析现存的部分历法术文和史载的历法推算日月交食的记录,并进行回推计算和比较,得出《统元历》、《乾道历》、《淳熙历》和《会元历》使用《崇天历》的交食推算方法,而《统天历》、《开禧历》和《成天历》可能使用了《纪元历》的交食推算方法。使用南宋的七部历法的算法分别计算了它们各自行用前后100年间的所有可见日食,并与真实的天象作比较,得到这些历法的推算精度。结论是:历法推算日食食甚的平均误差大约是0.5小时,食分误差是1.5分。  相似文献   

3.
《畴人传》及其续编"西洋附"整理、收录了明清时期所介绍的西方天文学家及数学家的传记.在梳理各编"西洋附"内容的基础上,比较了其中的编撰特点与得失,分析了编撰思想的变化,揭示出受19世纪50年代以来新译著的影响,《三编》、《四编》对西方科技的认识态度依然发生了些许转变.  相似文献   

4.
崇祯改历期间西法所报交食时刻始终采用百刻制纪时,且遵循小刻在大刻之后的传统。崇祯改历中的交食测验受到天气、计时和观测工具、管理者所认可的误差标准等因素影响,不能仅依据西法所报交食时刻考察西法预报的精度。崇祯改历并不缘起于西法推算崇祯二年日食优于《大统历》;崇祯改历中交食测验"与天密合"的标准与当代科学对精确度的追求不同,改历中各家交食测验较量的本质是测得何种历法误差最大。  相似文献   

5.
本文通过明代《通轨》和清代《细草》等材料,阐释明清官方如何借助"程式"和"算式"来操作天文算表,以实现历法推算的"程式化"。通过中朝历法交流中,李朝官员重赂钦天监,"密买"《细草》书册等细节,讨论了《细草》的使用和传播情况,及其在历算中的重要性。此外,分析说明了《通轨》和《细草》在带来推算便利的同时,也导致了历法原理被忽视,影响了明清历算的进一步发展。  相似文献   

6.
根据《开禧历》现存日食推算过程名称及天文常数,推断其日食计算方法与《纪元历》相同.给出了《开禧历》完整的日食推算公式以及使用《开禧历》计算淳祐五年七月朔日食的过程.将《开禧历》的日食算法编写为计算机程序,计算出1112至1303年间杭州的所有日食.与真实的天象作比较,得到《开禧历》日食计算精度为:日食食甚的平均误差0.46h,食分误差1.65分;有近20%的推算达不到当时的标准.  相似文献   

7.
通过韩国国立中央图书馆藏《回回历法》道光抄本,文章分析了自康熙朝回回天文学丧失官方地位之后,回回历法在道光年间的传承情况。与其他回回历法著作不同,道光本《回回历法》以道光甲午为历元,并对相应天文常数和算表进行了调整。该书在具体内容上参照了《明史·回回历法》以及梅文鼎的相关著作,但也做了不少调适,其中既有继承中国传统历法的内容,也借鉴了当时西洋历法的一些编撰特点。此外,本文还结合道光年间的历法改革,讨论了道光本《回回历法》的可能编撰动机。  相似文献   

8.
中国古代历法中的日食起讫算法是为了计算日食的初亏和复满时刻而设计的,该算法为《皇极历》所首创,此后历法均有涉及.通过构造日食起讫算法的理论模型,证实日食起讫算法应与月亮视差有关,中国古代的历法中,只有《钦天历》设计的日食起讫算法成功地考虑了月亮视差,由此指出中国古代日食起讫算法的一个缺陷.  相似文献   

9.
文章详细解读了《宋史》所记载的《崇天历》有关日食计算的算法术文和天文常数,并根据《崇天历》日食推算过程给出其完整的日食推算公式。作为一个算例,使用《崇天历》计算了天圣二年五月朔的日食情况,展示了这次日食推算的完整过程。与《纪元历》的日食算法比较,对《崇天历》的算法给出综合评价,指出《崇天历》的日食算法是合理的,但还不够优化。相比《纪元历》,《崇天历》的日食算法更为简单和粗糙,但其入交定日算法却比《纪元历》的更接近重建模型。  相似文献   

10.
日食食限是判断日食发生与否的重要参数,素来为中国天算家所重视。明末清初之际,西法食限知识传入中国,并被积极引入官方历法。通过分析中西历争背景下关于日食食限的争论,比对3部官方历法中的相关记述,并在此基础上研究清代学者对日食食限的认识程度与应用方式。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

16.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

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