修昔底德选用史料方法刍议

修昔底德的史著以叙述伯罗奔尼撒战争为主要内容,涉及希腊世界主要城邦的政治、军事、经济、外交以及海陆交通等方面丰富多样的史料。修昔底德按照自己处理史料的原则,对于战前史和战争史本身的史料分别采取了不同的处理方法。对于战前史料的选择和考信方法主要采用比较考异法和反溯法;对于当代史料的选用及考信方法主要采取实录法、辨异法、推测法、纠错法、隐微法等五种。修昔底德貌似如实直书的表象背后,隐含着名副其实的“修昔底德陷阱”。     

The Unitary Association Method of Relative Dating and Its Application to Archaeological Data

The primary objective of relative dating techniques is to determine a reliable sequence of archaeological deposits. This task becomes more difficult whenever our research steps beyond individual sites to the study of intercommunity relationships because we need to develop some means of associating unconnected deposits in time. Radiocarbon dating, as a stand-alone method, cannot always be used to draw reliable correlations between sites. The relevance of archaeological dates, including absolute dates, relies ultimately on the determination of artifact or sample associations and their respective superpositional relationships. The Unitary Association Method of Relative Dating is an alternative to seriation methods that is less susceptible to spatial variation and offers analytical strengths needed for regional chronological analyses.     

Solution Strategies for Three Problems in Empirical Fragility Curve Derivation Using the Maximum Likelihood Method

Solution strategies are presented to address three potential problems in the empirical derivation of fragility functions from empirical data using the maximum likelihood method. The first strategy addresses the case of fragility curves that cross, the second strategy incorporates demand uncertainty in fragility derivation from post-earthquake reconnaissance data, and the third strategy provides a framework for the resolution of conflict between empirical data and expert opinions. The advantages and disadvantages of the proposed solution strategies are discussed and their use is demonstrated by way of suitable illustrative examples.     

DEM Algorithm for Progressive Collapse Simulation of Single-Layer Reticulated Domes under Multi-Support Excitation

In this paper, the Member Discrete Element Method (MDEM) is modified and perfected for three aspects: the algorithm itself, loading and computational efficiency, and to accurately and quantitatively simulate the progressive collapse for large-span spatial steel structures. In addition, the corresponding computational programs are compiled. First, from the perspective of the method, a meshing principle for discrete element models is determined, a treatment for material nonlinearity and strain rate effect is proposed, and a damping model is established. Next, the Displacement Method is introduced to determine the multi-support excitation for the MDEM, and then motion equations of particles under multi-support excitation are derived. On this basis, the specific process of gravitational field loading is presented. Furthermore, parallel implementation strategies for the MDEM based on OpenMP are constructed. Finally, the collapse simulation of a 1/3.5-scaled single-layer reticulated dome shaking table test model under multi-support excitation is carried out. The comparison demonstrates that the ultimate load and failure mode as well as the complete collapse time of the numerical results are consistent with the experimentally measured responses, and the configuration variations from member buckling and local depression until collapse failure are fully captured. Moreover, the displacement time-history curves obtained using MDEM are almost identical to the experimental measurements, and there is a nuance only in the amplitude. It is verified that MDEM is capable of precisely addressing the collapse failure for large-span spatial steel structures. Additionally, the failure mechanism for structures of this type is naturally revealed.     

"That Food of the Memory which Gives the Clue to Profitable Research": Oral history as a source for local, regional, and family history in the nineteenth and early twentieth century

Numerous local, regional and family historians in the nineteenthand early twentieth century collected oral narrations and conductedinterviews as a form to document information that otherwisemight have never been preserved. Family historians, in particular,not only practiced interviewing relatives for family histories,but also encouraged the practice in how-to-do manuals amongtheir peers. While advocating the practice, family historiansalso reflected about the value of "traditionary evidence" collectedthrough interviews and other means. These reflections by familyhistorians mirrored the discussions about the value of traditionsand memories as historical sources among several professionalhistorians at the time. These reflections were shaped by a modernizedunderstanding of tradition, which combined a reverential approachto the authoritarian element of tradition with a critical approachquestioning the validity of tradition. In this context, oralhistory was both a tool to negotiate the value of traditionand a mirror to the contemporary understanding of tradition.     

Bone weight,meat yield estimates and cod (Gadus morhua): A preliminary study of the weight method

Past approaches to the Weight Method (use of the weight of excavated bone assemblages to evaluate the relative potential meat yield of the animals from which they came) are critically reviewed. They do not account for both inter-taxon and intra-taxon variability in the relationship between bone weight and total body or soft tissue weight. Critics of the Weight Method have assumed that these problems are insurmountable. It is argued here that they can be overcome practically. Solutions lie in the integration of classic Weight Method approaches, which assume a consistent ratio of bone weight to body weight between different taxonomic and size groups, with the understanding of animal scaling provided by studies of skeletal mass allometry. Allometric equations derived from original data (regarding cod, Gadus morhua) and available from published sources (regarding mammals and birds) are used to illustrate this argument. Three practical approaches to the Weight Method are suggested and briefly explored, using bone weight data from Earls' Bu, a Norse site in Orkney, Scotland, as a case study.     

Assessing Seismic Behavior of a Masonry Historic Building considering Soil-Foundation-Structure Interaction (Case Study of Arge-Tabriz)

ABSTRACT

Historic heritage buildings are a part of historic basis of each society and an economic resource. Therefore, preserving and maintenance of these buildings are cultural, economic and social demand. This research investigates the seismic performance of a historical building named Arg of Tabriz (Arge Alishah) that dates back to 14th century and is located at the city center of Tabriz (NW of Iran). Static, modal, and finally nonlinear dynamic (time history) analysis were performed by both “Considering Soil-Structure Interaction (SSI)” and “fixed base (ignoring SSI)” Cases.

It is found from the results that, SSI extremely affects mode shapes and their frequencies and depending on the frequency content of the records, can has an incremental or decremental effect on structural responses. As expected, the building of Arg could carry gravity loads easily and despite its stability against earthquake loading in fixed base case, showed a weakness (especially in eastern and western walls direction) and overturned when it was analyzed in SSI case because of yielding of the surrounding soil.     

Experimental and Analytical Study of Seismic Soil-Pile-Structure Interaction in Layered Soil Half-Space

The dynamic interaction of pile foundations, embedded in a horizontally stratified soil profile, with superstructures under low to moderate earthquake excitation can be handled in different ways. In this article, the soil-pile-superstructure dynamic interaction problem has been investigated using the coupled finite element-boundary element method. Comparison with shaking table experiments of a small scale model pile shows a good correlation with the proposed method in terms of the kinematic response of pile foundations and the structural response. A parametric study of the proposed model has yielded important results essentially concerning the amplification factors of the pile foundation and the superstructure.     

Effects of Different Record Selection Methods on the Transverse Seismic Response of a Bridge in South Western British Columbia

The seismic response of a continuous 4-span bridge designed according to the current Canadian seismic provisions is investigated using Incremental Dynamic Analysis (IDA). Different earthquake types, including shallow crustal events, interface Cascadia subduction, and deep inslab subduction are considered. The median collapse capacities calculated using different record selection methods including Conditional Mean Spectrum (CMS)-based, Uniform Hazard Spectrum (UHS)-based, and epsilon-based methods are compared. The use of the epsilon-based method generally resulted in the highest collapse capacity predictions, but the CMS-based method was less sensitive to the number of records considered in the IDA.     

Correlation between modern plant δN values and activity areas of Medieval Norse farms

This further nitrogen isotopic study of Greenlandic Norse archaeological sites provides new evidence of the affect of past human activity on modern plant δ¹⁵N values. Grass samples were taken from a number of spatially defined features at four Norse farms and one site interpreted to be a seasonally occupied herding station (sæter). At the farms, un-naturally high δ¹⁵N values were found for plants from each sampled feature, including those from the likely infields and a churchyard. At the sæter no strong isotopic effect was expected and none was found. Comparing the data from the farms we found that the average plant δ¹⁵N values were similar for features that were functionally alike. We conclude from these observations, that the unusually high plant δ¹⁵N values reflect the strong conservation of the isotopic composition of the nitrogenous materials deposited in the past, and the magnitude of the values reflects the amount of this material admixed in the soil. The results confirm previous exploratory studies of this isotopic effect and further demonstrate its potential value as an archaeological tool.