关于中国古代海军史几个问题的再思考

哀公十年(前485年)，吴徐承帅舟师沿海北上攻齐进行海战事，似难确认。襄公二十四年(前549)，楚以舟师伐吴，是为史籍明确记载的第一次动用舟师的征战，但恐难排除此前已发生过动用舟师征战的事实，是故中国古代海军的产生(形成)时间，尚需进一步科学、准确论证。“海军”是个历史范畴，在不同的历史时期具有不同的形态，称谓也有所变化。中国古代海军的主要称谓有舟师、楼船军、水军、水师等。     

Topic Modeling and Text Analysis for Qualitative Policy Research

This paper contributes to a critical methodological discussion that has direct ramifications for policy studies: how computational methods can be concretely incorporated into existing processes of textual analysis and interpretation without compromising scientific integrity. We focus on the computational method of topic modeling and investigate how it interacts with two larger families of qualitative methods: content and classification methods characterized by interest in words as communication units and discourse and representation methods characterized by interest in the meaning of communicative acts. Based on analysis of recent academic publications that have used topic modeling for textual analysis, our findings show that different mixed‐method research designs are appropriate when combining topic modeling with the two groups of methods. Our main concluding argument is that topic modeling enables scholars to apply policy theories and concepts to much larger sets of data. That said, the use of computational methods requires genuine understanding of these techniques to obtain substantially meaningful results. We encourage policy scholars to reflect carefully on methodological issues, and offer a simple heuristic to help identify and address critical points when designing a study using topic modeling.     

Reflections on North American Pacific Coast prehistory

The Pacific Coast of North America was occupied by many distinctive groups of coastal hunter-gatherers at the times of early contacts with Europeans. Despite significant cultural diversity, Pacific Coast peoples shared lifeways oriented toward generally similar marine, nearshore, littoral, and estuarine habitats. In this paper, we examine some major issues that guide much of the archaeology done along the Pacific Coast, then discuss some of the theoretical and methodological problems that limit the efficacy of archaeological reconstructions. Most archaeological research conducted on North America's Pacific Coast has been oriented toward the search for the origins and development of a variety of cultural patterns. A comparative review of California and Northwest Coast sequences provides interesting parallels and discrepancies in the approaches taken in studying some of the major issues in Pacific Coast prehistory.     

汉代漆器的剖析

通过制备并分析一系列模拟漆膜样品。建立了有助于鉴定汉代漆器成分的剖析方法。经裂解气相色谱、差热分析、色谱一红外联用等现代分析技术对出土的汉代漆器残片样品的综合分析,证实在西汉漆器制造中已使用桐油或其它的添加剂,并依据剖析的结果,对某些汉代漆器的原材料差异作了初步探讨。     

Determination of the Fineness of Medieval Coins—Evaluation of Methods in a Case Study of a Medieval Pfennig

The original fineness of coins is very important information that can help us to understand the commercial situation in a wide historical context. This paper deals with a comparison of analytical methods suitable for the evaluation of the actual and original fineness of coins based on a detailed case study of a medieval coin sample. Both non‐destructive (i.e., scanning electron microscopy/energy‐dispersive X‐ray spectroscopy, X‐ray fluorescence, atomic force microscopy and hydrostatic weighing) and destructive (i.e., inductively coupled plasma – mass spectrometry and the Volhard titration method) techniques were used. The original fineness can be also deduced from knowledge of the internal structure of the coin (limited miscibility of copper and silver). A new analytical method based on a combination of a micrograph of the metallographic cross‐section with consequent image analysis was developed for determination of the original fineness. The proposed approach is relatively simple and provides reliable values. Sample heterogeneity and its impact on the determination of fineness are also discussed.     

饱水木质文物的风冷干燥脱水研究

许多出土饱水木质文物因其降解严重、含水率较高,容易在脱水过程中出现不可逆的收缩变形以及开裂现象,从而遭到严重破坏。因此,饱水木质文物脱水方法的研究是文物保护工作中的重要课题。为探究风冷冷冻法对饱水木质文物脱水的效果,以一批无法复原的出土饱水木质文物为研究对象,在对其材种、含水率、基本密度及化学成分进行了测定和分析后,使用一台风冷电冰箱在-18℃条件下对样品进行了风冷干燥脱水处理,记录脱水时间和脱水效果,并分析了该方法的传质传热特点,证明了风冷干燥法用于饱水木质文物的脱水干燥能够取得良好效果,并且具有对文物干预小、适用性广、操作简便、成本低廉等优点,为饱水木质文物的脱水处理提供了一种新的思路。     

The greening of Oscar Wilde: situating Ireland in the Wilde wars

The importance of Ireland to an understanding of Oscar Wilde has been the subject of contentious discussion in recent years. For one group of critics Wilde has been considered “a militant Irish republican”, an Irish “terrorist by another name”, whose literary practices resembled those of “guerrilla warfare”, an ardent Home Ruler and Parnellite, and committed Irish nationalist whose work is suffused with references to Ireland and the Irish Question, very influenced by his Irish background and political views, possibly shaped by a genuine interest in and awareness of Irish folklore and the Irish oral tradition, and deeply engaged with issues of Irish identity and culture. For an opposing set of critics Wilde should at best be considered a “reluctant” Irish patriot, who referenced his Irish “identity” only when it suited him commercially, was more interested in exploiting intellectual fashions and fads than making genuine political points, was a shallow thinker in most areas of life and certainly didn’t use his writing to pursue Irish nationalist issues, was probably more of a British imperialist than an Irish nationalist, knew precious little about Irish folklore or Irish oral traditions, and his works contain few if any references to Irish issues or themes. The differences between these two interpretive communities certainly seem quite large, and these differences have been emphasised in a disputatious manner which has shed more heat than light on the messy matter of Wilde’s national identity. In this article I want to begin to clear up some of the misunderstandings I think have crept into this critical dispute and suggest fruitful ways in which opposing critics can come together in if not harmony then perhaps a less acrimonious, more productive way.     

Multiphase flow simulation through porous media with explicitly resolved fractures

Accurate simulation of multiphase flow in fractured porous media remains a challenge. An important problem is the representation of the discontinuous or near discontinuous behaviour of saturation in real geological formations. In the classical continuum approach, a refined mesh is required at the interface between fracture and porous media to capture the steep gradients in saturation and saturation‐dependent transport properties. This dramatically increases the computational load when large numbers of fractures are present in the numerical model. A discontinuous finite element method is reported here to model flow in fractured porous media. The governing multiphase porous media flow equations are solved in the adaptive mesh computational fluid dynamics code IC‐FERST on unstructured meshes. The method is based on a mixed control volume – discontinuous finite element formulation. This is combined with the P_N+1DG‐P_NDG element pair, which has discontinuous (order N+1) representation for velocity and discontinuous (order N) representation for pressure. A number of test cases are used to evaluate the method's ability to model fracture flow. The first is used to verify the performance of the element pair on structured and unstructured meshes of different resolution. Multiphase flow is then modelled in a range of idealised and simple fracture patterns. Solutions with sharp saturation fronts and computational economy in terms of mesh size are illustrated.     

Interconnected Epistyles of Marble Monuments Under Axial Loads

The restoration of destroyed connections of epistyles joined together by means of metallic connectors is among the most difficult problems encountered by scientists working for the conservation/restoration of monuments made of marble. The complexity of the geometry and the interaction of three completely different materials (metal-filling material-marble) constituting the connection render the study (either experimental or analytic) extremely complicated. In this direction a numerical analysis is presented here in order to deeply understand the response of a typical ancient connection subjected to axial loads as well as to quantify the influence of some geometric parameters on its response. The parameters studied include the length of the connector, the width of its flanges, the depth of the groove (mortise), the existence or not of relieving space and the filling material’s volume. The numerical model was calibrated and validated according to the results of an earlier experimental study realized on the worksite of the Parthenon Temple. It was concluded that the interventions required to relieve the stress field by changing the size of the connector are disproportional to the respective positive effect on the response of the connection. Moreover it was proved that the most beneficial parameter is the relieving space.