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991.
Northwestern Italian weak-motion data were used to study attenuation characteristics of horizontal peak ground acceleration (PGA) and horizontal peak ground velocity (PGV) from earthquakes of local magnitudes (M l ) up to 5.1. Data have been provided by the RSNI (Regional seismic network of Northwestern Italy) and RSLG (Regional seismic network of Lunigiana-Garfagnana) waveform database. The database consists of more than 14000 horizontal components recorded in the period 1999-2002 by both broadband and enlarged band seismometers. The accuracy of the procedure used to extract PGA values from the velocity recordings was verified comparing observed and derived PGA values at station STV2, which was equipped with both a temporary K2 Kinemctrtcs accelerometer and Guralp CMG40 broadband sensor. The attenuation of both peak ground acceleration and peak ground velocity was found to be logarithmically distributed with a strong attenuation for low distances (less than 50 km) and low M l values (<3.0). The resulting equations are:

Log(PGA)=?3.19+0.87M?0.042M 2?1.92 Log(R)+0.249S,

Log(PGA)=?4.23+0.76M?0.018M2?1.56 Log(R)+0.230S,

where PGA is expressed in g, PGV is expressed in m/s, M is local magnitude, R is the hypocentral distance in kilometers and S is a dummy variable assuming values of 0 and 1 for rock and soil respectively. For increasing distance and magnitude, both PGA and PGV values show a linear distribution. The validity range of the obtained attenuation relationships is 0–200 km for distances and M l up to 4.5. Sensitivity studies performed by analysis of residuals, showed that predicted PGA and PGV values are stable with respect to reasonable variations of the model and distances providing the data. Comparisons with attenuation relationships proposed for Italian region, derived from strong motion records, are also presented.  相似文献   
992.
In the Six dynasties, the clans of the scholar-official stratum not only occupied a dominant place in social and cultural life but also played an important role in maintaining Chinese civilization. As a succession of northern minorities entered the Central Plains, foreign culture became widespread and the Chinese people and culture experienced an unprecedented crisis. Thanks to the scholar-official clans who shouldered the burden of preserving Chinese culture, Chinese civilization was able to persist through the ages to become an “unbroken” civilization. These clans can be categorized in three groups according to their territorial origin: “Clans of the Wu Area” which developed in Jiangnan after the Han dynasty; “Immigrant Clans” which moved to Jiangnan from the north during the Jin dynasty and the ensuing dynasties, these being referred to jointly as “the Southern Clans”; and “the Northern Clans,” being those clans that remained in their homelands (Shandong and the Central Shaanxi Plain) during the period of ethno-national amalgamation in the north of China. Though these clans had various cultural characteristics due to different historical roots, cultural traditions and ancestry, their clan learning had a common core, i.e., the study and practice of Confucian rites as established in the Han dynasty. This formed the basis for the integration of Han with other cultures, making a sound foundation for the further development of the Chinese civilization.  相似文献   
993.
A novel sampling technique for the analysis of glass is described, which involves the removal of minute particles from an object with a diamond‐coated file, followed by energy‐dispersive X‐ray analysis in the scanning electron microscope (SEM/EDXA). The particles are fixed to adhesive carbon discs and carbon coated without grinding or polishing. Mean compositions are determined for 10 arbitrarily selected particles above a minimum grain size of 150 mm and normalized to totals of 100%. Tests were carried out on two standard soda–lime–silica glasses of well‐characterized composition, using two files of different grade. The analyses showed good agreement with the accepted values of all elements. Although the precision is somewhat reduced, this highly portable and quasi non‐destructive microsampling procedure provides almost the same information as that gained from samples embedded and polished in the normal way. Its application is thought to be especially useful for the investigation of intact glass objects and ceramic glazes.  相似文献   
994.
The lead isotope compositions of many different samples from lead ingots of Roman age from two relicts (from Cabrera, and from Saintes‐Maries‐de‐la‐Mer) of the Western Mediterranean have been measured. Other lead isotope analyses of ores, metals or lead ingots from mines of Sierra Morena and from Cartagena and Sardinia have been accomplished. All the lead isotope measurements have been performed at the Joint Research Centre of the European Union, Ispra (Va), Italy. The samples have been prepared in a class 100 clean room, using only ultrapure reagents and FEP materials. In view of the archaeological arguments, it was possible to believe that the Roman lead ingots of the Saintes‐Maries‐de‐la‐Mer 1 wreck came from Spanish lodes, as well as those of the Cabrera 5 wreck. In fact, while the comparison between the first group of ingots (Cabrera 5) and the lead from Sierra Morena is consistent, the correspondence between the second group of ingots (Saintes‐Maries‐de‐la‐Mer 1) and the Cevennes ores (southern France) gives rise to several problems concerning the archaeological and physical origins. These problems are discussed.  相似文献   
995.
There is an increasing awareness of the potentials of nonlinear modeling in regional science. This can be explained partly by the recognition of the limitations of conventional equilibrium models in complex situations, and also by the easy availability and accessibility of sophisticated computational techniques. Among the class of nonlinear models, dynamic variants based on, for example, chaos theory stand out as an interesting approach. However, the operational significance of such approaches is still rather limited and a rigorous statistical-econometric treatment of nonlinear dynamic modeling experiments is lacking. Against this background this paper is concerned with a methodological and empirical analysis of a general misspecification test for spatial regression models that is expected to have power against nonlinearity, spatial dependence, and heteroskedasticity. The paper seeks to break new research ground by linking the classical diagnostic tools developed in spatial econometrics to a misspecification test derived directly from chaos theory—the BDS test, developed by Brock, Dechert, and Scheinkman (1987). A spatial variant of the BDS test is introduced and applied in the context of two examples of spatial process models, one of which is concerned with the spatial distribution of regional investments in The Netherlands, the other with spatial crime patterns in Columbus, Ohio.  相似文献   
996.
This paper outlines the environmental history of the Tigrean Plateau (northern Ethiopia) during the Holocene, based on the available geomorphological, palynological, archaeological, and historical evidence. At present, it seems that (1) the plateau experienced a more humid climate with a denser vegetation cover during the Early Holocene; (2) Soil erosion due to clearing vegetation began in the Middle Holocene; (3) agricultural activity was intensified in the Late Holocene, as a consequence of the rise of a state; (4) demographic pressure increased from the early first millennium BC to the mid–first millennium AD, causing soil erosion; (5) environmental degradation and demographic decline occurred in the late first millennium AD; (6) the vegetation cover was regenerated in the early second millennium AD; and (7) progressive vegetation clearance started again in the second half of the second millennium AD.Cet article trace l'histoire ambiante du Plateau Tigréen dans l'Holocène en utilisant les données géomorphologiques, palynologiques, archéologiques et historiques. Il semble que (1) dans l'Holocène ancien le plateau était caractérisé par une phase humide avec une dense végétation; (2) l'érosion causée par l'abbattage de la végétation commen¸a dans l'Holocène moyen; (3) l'activité agricole s'inténsifia à la fin de l'Holocène, par conséquence de l'essor d'un état; (4) la pression démographique augmenta de plus en plus du début du premier millénaire av. J.-Ch. à la moitié du premier millénaire ap. J.-Ch.; (5) la dégradation ambiante et la diminution démographique se vérifièrent à la fin du premier millénaire ap. J.-Ch.; (6) une régéneration de la vegetation se vérifia au début du seconde millénaire ap. J.-Ch.; et (7) l'abbatage de la végétation recommen¸a dans la seconde moitié du seconde millénaire ap. J.-Ch.  相似文献   
997.
Stable carbon and nitrogen isotope analyses of bone collagen, and stable carbon and oxygen isotope analyses of the bone's structural carbonate, were performed on 120 individuals representing 33 vertebrate species, including a single human bone find, collected from the Late Neolithic settlement at Pestenacker, Bavaria, Germany. We were thus capable of reconstructing a rather complex food web and could also address particular issues, such as whether humans influenced the diet of their domestic animals as opposed to their wild relatives, or whether humans perhaps had to compete over food with their domesticates. A rather unexpected result was that freshwater fish, which could be captured in the nearby river Lech, a major tributary of the Danube, contributed to the human diet only occasionally. As for mammals, it was also possible to recognise different trophic levels for birds and aquatic vertebrates, applying stable isotope analyses to both bone collagen and structural carbonate. In the case of fish, δ18O values at least revealed a physiological regularity in terms of temperature preference, besides diet. Conceivably, variability of δ18O in surface water as reflected, for example, by species that avoided human settlements, may help to characterise past ecosystems and to define site catchment exploited by Neolithic man in the course of food acquisition. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
998.
This paper discusses trepanation frequency data from the Chachapoya region of the northern highlands of Perú. New data from three skeletal samples are presented: Kuelap, Laguna Huayabamba, and Los Pinchudos, as well as isolated crania housed at the Chachapoya Museo Instituto Nacional de Cultura. The vast majority of the trepanations are circular in shape, except for one individual exhibiting as many as three roughly square trepanations. Evidence for healing is prevalent, with examples of both associated periosteal reaction of nearby outer table bone, as well as for healing of the insult itself. Only one case demonstrates a clear association between a traumatic injury and a trepanation event. The purpose or function of the remaining cases of trepanation, however, remains elusive. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
999.
1000.
Differentiation of the genetic and the acquired anaemias, particularly in areas of the world where they may co‐exist, has been a challenge for palaeopathologists for over 100 years. In this paper we present macroscopic and radiographic skeletal lesions that are associated with the thalassemias in a 14‐year‐old girl from a modern reference collection of the University of Athens. This individual is of known sex, age, cause of death, place and dates of birth and death. The case is examined in terms of epidemiology, growth, distribution and severity of lesions and differential diagnosis. The entire skeleton is affected by marrow hyperplasia: lesions of the axial skeleton are extreme, and the appendicular skeleton is severely affected as well. The odontofacial manifestations that are diagnostic of thalassemia and differentiate it from other anaemias are present and include: maxillary and mandibular hyperplasia, reduced sinuses, displacement of maxillary dental structures, overbite, and generalised osteopenia. The development of extreme bone lesions and the ‘advanced’ age‐at‐death of this individual is explained as either the result of thalassemia major under a low transfusion regimen that was the norm during her lifetime, or to a form of thalassemia intermedia that allows survival to later life at the expense of gross skeletal alterations. The present status of skeletal studies in Greece does not support the identification of a genetic anaemia in past populations. The potential contribution of the current analysis in differentiating the anaemias in antiquity is evaluated. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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