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1.
The grounds of 51 post‐Byzantine icons (Eastern Orthodox panel paintings) were studied by means of analytical techniques. The artefacts cover the period from the mid‐15th to the mid‐19th century and originate mainly from western (Epirus and the Ionian Islands) and southern Greece (Crete). The findings are examined in the light of technical recipes from related areas and eras, while special insights are gained from the exploration of a gypsum processing recipe by Dionysius of Fourna. A spectrum of ground fabrication practices that is richer than that reported so far or can be deduced from surviving Greek recipes is documented; three instances of ‘grosso‐sottile’ type grounds and a case of ‘inverse grosso‐sottile’ ground are among the reported novel, for post‐Byzantine icons, findings. Moreover, a case of an early icon restoration intervention is documented.  相似文献   

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Underwater surveys along the Israeli Carmel coast have revealed six cargoes of iron semi‐products associated with shipwrecks. They are described and dated according to the associated artefacts. Metallographic and chemical analyses on samples from the biggest cargo have determined the stages of the chaîne opératoire, identified the properties of the iron and characterized the iron trade along the Israeli coast. The new discoveries contribute to our understanding of the circulation of iron in the South Levant, which was characterized by an almost complete absence of local iron production. During the Byzantine and Crusader periods, this absence was compensated by long‐distance sea trade, depending on political circumstances and restrictions. Three main types of iron semi‐products were identified: (a) partly consolidated blooms, (b) short pointed bars and (c) elongated pointed bars. The cargoes discovered represent a time period of nearly a millennium. Altogether, 148 iron semi‐products were studied. Of these, 166 were from cargo a, which was dated by coins to around 1130–1200 ce . Those coins could have been imported from Europe for Crusader military and civil uses in the Levant. The iron from cargoes b, d and f, dated perhaps to the Byzantine period, could have been imported from Anatolia or Venice for military and civil purposes.  相似文献   

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The p‐compact‐regions problem involves the search for an aggregation of n atomic spatial units into p‐compact, contiguous regions. This article reports our efforts in designing a heuristic framework—MERGE (memory‐based randomized greedy and edge reassignment)—to solve this problem through phases of dealing, randomized greedy, and edge reassignment. This MERGE heuristic is able to memorize (ME of MERGE) the potential best moves toward an optimal solution at each phase of the procedure such that the search efficiency can be greatly improved. A dealing phase grows seeded regions into a viable size. A randomized greedy (RG of MERGE) approach completes the regions' growth and generates a feasible set of p‐regions. The edge‐reassigning local search (E of MERGE) fine‐tunes the results toward better objectives. In addition, a normalized moment of inertia (NMI) is introduced as the method of choice in computing the compactness of each region. We discuss in detail how MERGE works and how this new compactness measure can be seamlessly integrated into different phases of the proposed regionalization procedure. The performance of MERGE is evaluated through the use of both a small and a large p‐compact‐regions problem motivated by modeling the regional economy of Southern California. We expect this work to contribute to the regionalization theory and practice literature. Theoretically, we formulate a new model for the family of p‐compact‐regions problems. The novel NMI introduced in the model provides an accurate, robust, and efficient measure of compactness, which is a key objective for p‐compact‐regions problems. Practically, we developed the MERGE heuristic, proven to be effective and efficient in solving this nonlinear optimization problem to near optimality. El problema de regiones compactas tipo p (p‐compact regions) consiste en la búsqueda de la agregación de n unidades espaciales atómicas que produzca regiones contiguas de tipo p‐compacto. Este artículo reporta los esfuerzos de los autores en el diseño de un marco heurístico MERGE (memory‐based randomized greedy and edge‐reassignment) el cual resuelve este problema a través de las fases de la negociación (dealing), codicia aleatorizada (randomized greedy), y la reasignación de bordes (edge reassignment). El heurístico MERGE es capaz de memorizar ( ME de MERGE) los mejo)res desplazamientos posibles hacia una solución óptima en cada fase del procedimiento de tal manera que la eficiencia de la búsqueda puede ser mejorada en gran medida. La fase de negociación crea regiones “sembradas” aleatoriamente y las hace crecer en diferentes tamaños . El componente de codicia aleatorio (RG de MERGE) completa la fase de crecimiento de las regiones y genera un conjunto factible de regiones tipo p. La reasignación de bordes se realiza vía una búsqueda local (E de MERGE) que afina los resultados con el fin the alcanzar los objetivos. Además, el enfoque propuesto aquí utiliza el momento de inercia normalizado (normalized momento of inertia‐NMI) como método para el cálculo de la compacidad de cada región. El artículo discute en detalle el funcionamiento de MERGE y cómo esta nueva medida compacidad puede integrarse perfectamente en las diferentes fases del procedimiento de regionalización propuesto. Para ilustrar y evaluar el desempeño de MERGE, el metodo es aplicado a dos problemas de p‐compact regions, uno grande y uno pequeño, basados en el modelado de la economía regional del sur de California. Los autores esperan que este trabajo contribuya a la literatura teórica y práctica de la regionalización. En términos teóricos, se formula un nuevo modelo de la familia de problemas de p‐compact regions. El NMI equipa al modelo con una novedosa forma de obtener una medida exacta, robusta y eficiente de compacidad, que es un objetivo clave para los problemas región compacta tipo p. En términos prácticos, se desarrolla MERGE, un procedimiento heurístico que ha demostrado ser eficaz y eficiente en la solución de este problema de optimización no lineal de manera casi óptima. p紧凑区域问题包含寻找一种聚集方法,将n个不可分割的空间单元集合成p紧凑的邻近区域。本文阐述了一种启发式架构MERGE(基于记忆的随机贪婪和边界再赋值算法),通过处理、随机贪婪和边界再分配这几个阶段解决p紧凑问题。MERGE启发式框架能存储 处理过程每个阶段中,向一个最优解的潜在最佳移动方式,从而可极大地提升搜索效率。一个处理阶段可将种子区域生长到可行大小。而一个随机贪婪阶段能完成区域增长并生成p区域的可行集。在边界再分配的局部搜索阶段对结果进行微调以达到更好的目标。此外,引入标准化的惯性矩作为每个区域紧凑度计算的选择方法。本文详细讨论了MERGE的工作原理,以及这种新的紧凑度测算方法如何能无缝地整合到所提出的区域化流程的不同阶段。通过在南部加州区域经济建模中一小一大两个p紧凑区域问题的应用,对MERGE的性能进行评估,期望该工作能够对区域化理论和实践作出贡献。理论上,提出了可解决p紧凑区域这类问题的新模型。在模型中引入新颖的标准化惯性矩这一精确的、鲁棒的和有效的紧凑度度量方法,是解决p紧凑区域问题的关键目标;实践上,本文发展了MERGE启发式框架,并证明了它在解决这种非线性优化问题近优性的有效性和高效性。  相似文献   

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The hub location problem has been widely used in analyzing hub‐and‐spoke systems. The basic assumption is that a large number of demands exist to travel from origins to destinations via a set of intermediate transshipment nodes. These intermediate nodes can be lost, due to reasons such as natural disasters, outbreaks of disease, labor strikes, and intentional attacks. This article presents a hub interdiction median (HIM) problem. It can be used to identify the set of critical facilities in a hub‐and‐spoke system that, if lost, leads to the maximal disruption of the system's service. The new model is formulated using integer linear programming. Special constraints are constructed to account for origin‐to‐destination demand following the least‐cost route via the remaining hubs. Based on the HIM problem, two hub protection problems are defined that aim to minimize the system cost associated with the worst‐case facility loss. Computational experiment results are presented along with a discussion of possible future work. El problema de la ubicación de la central (hub) ha sido ampliamente analizado para el caso de los sistemas de sistemas radiales (hub‐and‐spoke). La presunción inicial es que existe un gran número de demandas que viajan desde puntos de origen hasta sus puntos de destino a través de un set de nodos intermedios de trasbordo. Estos nodos intermedios pueden perderse por diferentes motivos, como desastres naturales, brotes de enfermedades, huelgas de trabajadores, o ataques intencionales. Este artículo presenta un problema de tipo mediana de interdicción de hub, conocido como hub interdiction median‐HIM. Puede usarse para identificar un set de instalaciones críticas de un sistema tipo hub‐and‐spoke que, si se pierde, conduce a la máxima interrupción del servicio del sistema. El nuevo modelo se ha formulado utilizando programación entera lineal, (integer linear programming‐ILP). El modelo construye restricciones especiales para dar cuenta de la demanda de “origen‐a‐destino” (O‐D), siguiendo la ruta de menor costo, a través de los hubs restantes. Basándonos en el problema de HIM, se definen dos problemas de protección de hub que buscan minimizar el costo asociado al peor caso posible de pérdida de instalaciones. Se presentan además, resultados de experimentos computacionales, así como a una discusión sobre posibles futuros trabajos en la materia. 枢纽区位研究已广泛应用于中枢辐射型系统分析,其基本假设条件为起始点到目的地之间存在大量旅行需求的中间转运节点。但自然灾害、突发疾病、劳务罢工和蓄意攻击等因素可能导致中间转运节点的丧失。本文提出了一种枢纽封闭中心模型(HIM),可用于识别中枢辐射型系统的重要节点,一旦这些节点丧失,将导致整个系统服务最大程度的瓦解。新模型通过整数线性规划公式建立。模型特殊约束条件的建立基于最小成本路径通过余下枢纽的花费来解释始发到目的地( origin‐to‐destination)需求量。基于HIM问题,双枢纽保护问题被定义为旨在最小化系统花费及其与之关联的最坏情况下节点丢失问题。最后,根据计算的经验结果讨论未来可能深入的研究。  相似文献   

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Metal leaves were widely used as decorative materials in post‐Byzantine ritual painting. Fifty‐two icons (mid‐15th to mid‐19th centuries) were studied by means of analytical techniques in order to reveal the materials and techniques encountered in their metal‐leaf decorations. High‐purity gold leaf was used throughout the studied period. Silver was employed rarely and mostly during the latter part of the period in consideration, while metal powders were mostly used from the mid‐18th century onwards. The identification of a gold–silver powder mixture and an ‘electrum’‐type alloy are among the reported findings, which are novel for post‐Byzantine icons. Three micromorphologically distinct highlighting techniques were also documented.  相似文献   

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In 2005 and 2006 the remains of great armed vessels dated from the 16th century were discovered within an archaeological survey framework led by the Société d'Etudes en Archéologie Subaquatique (SEAS) in Saint‐Florent Bay (north Corsica, France). The preliminary study of the two archaeological sites located, named Mortella II and Mortella III, sheds light on these highly interesting shipwrecks and the contribution their excavation—programmed for 2010—will be able to provide to the maritime archaeology of this period, about which relatively little is known. © 2010 The Author  相似文献   

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When in 1875 Queen Olga of Greece insisted a multi‐part chant be introduced in the Athens Cathedral, a widespread debate about the influence of Western European culture upon Greek‐Orthodox tradition was initiated in Athens. With a significant part of this debate originating in mid‐century Vienna, and Russian musical influences affecting the form of the otherwise ancient Byzantine chant, the issue of polyphony acquired cultural‐historical dimensions intimately connected to historical continuity and the Orthodox‐Christian musical tradition. The debate transformed rapidly from a musicological enquiry into a matter of national identity, and an otherwise innocent aesthetic choice showcased the musical dimensions of Greek national claims at continuity. This article examines the historical contingencies that fuelled this debate, showcases the importance of patronage for musical transference and highlights the potency of Greek national Orthodoxy as a carrier of historical continuity for the ethnic group, here seen through music.  相似文献   

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Eulogius of Córdoba, the principal recorder of the ninth‐century Córdoban martyrs’ movement, copied for posterity a polemic biography of the Prophet Muhammad. The lost original is the earliest such text known in Latin, despite the longstanding tradition of anti‐Islamic polemic in the Greek east. However, textual analysis indicates that Eulogius revised the original biography, and that his revisions were influenced by the polemic of John of Damascus. Eulogius's exposure to John's writings probably came through personal contact with a monk from the monastery of Mar Saba, contact which offers rare evidence of a non‐textual transmission of ideas.  相似文献   

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Spatial patterns of minimum monthly river discharge in the North American Pan‐Arctic and its potential controls are explored with geographically weighted regression (GWR). Minimum discharge is indicative of soil water conditions; therefore, understanding spatial variability of its controls may provide insights into patterns of hydrologic change. Here, GWR models are applied to determine a suitable combination of independent variables selected from a set of eight variables. A model specification with annual mean river discharge, temperature at time of minimum discharge, and biome describes well the spatial patterns in minimum discharge. However, minimum discharge in larger watersheds is influenced more by temperature and biome distributions than it is in small basins, suggesting that scale is critical for understanding minimum river discharge. This study is the first to apply GWR to explore spatial variation in Pan‐Arctic hydrology. Factores de control espaciales y dependientes de escala en las descargas fluviales mínimas de ríos Pan‐Articos en Norteamérica. El artículo explora los patrones espaciales de caudales fluviales mínimos mensuales la región pan‐ártica de Norteamérica y sus posibles factores de control haciendo uso de una regresión ponderada geográficamente (geographically weigted regression‐GWR). Los caudales mínimos son indicadores de las condiciones del agua en el suelo, y por lo tanto el entendimiento de la variabilidad espacial de los factores que los controlan puede ayudar a comprender los patrones de cambio hidrológico. En el presente estudio, varios modelos de tipo GWR son aplicados para determinar una combinación adecuada de variables independientes seleccionadas a partir de un conjunto de ocho variables. El modelo que utiliza la media anual media de descarga fluvial, la temperatura en el momento de caudal mínimo, y el bioma, proporciona una buena descripción de los patrones espaciales en la descarga mínima. Sin embargo, en las cuencas hidrográficas grandes, la descarga mínima está más influenciada por la temperatura y la distribución de los biomas que en el caso de cuencas más pequeñas, lo que sugiere que la escala es fundamental para entender la descarga mínima fluvial. Este estudio es el primero en aplicar GWR para comprender la variación espacial en la hidrología de la región pan‐ártica. 基于GWR(地理加权回归模型)对北美泛北极地区月份最小河流流量的空间模式和潜在控制进行研究。最小流量暗示水土条件;因此,理解空间分异及控制可深刻理解水文变化的模式。GWR可从8个变量中提取一组独立变量的适当组合。通过年均河流流量、最小流量时的温度和生物群落,来描述最小下泄流量的空间格局。在大范围流域中,最小流量受到温度和生物群落分布的影响大于在小规模的流域,揭示出在河流最小流量分析中尺度是非常重要的。本文首次将GWR应用于泛北极水文空间异质性分析。  相似文献   

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Excavations at Yenikap? in Istanbul, Turkey, related to the Marmaray Project, have unearthed remains of Constantinople's Theodosian Harbour, including 37 Byzantine shipwrecks of 5th‐ to 11th‐century date. Eight of these shipwrecks, six round ships and two of the first long ships, or galleys, to be excavated from the Byzantine period, were studied by archaeologists from the Institute of Nautical Archaeology. These well‐preserved shipwrecks are an important new source of information on the maritime commerce of Constantinople and the gradual shift from shell‐based to skeleton‐based shipbuilding in the Mediterranean during the second half of the first millennium AD.  相似文献   

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Traditionally, documentary evidence (mainly medical works and the vitae and miracles of saints) served as the primary source of information for perinatal nutrition in the Byzantine era. In the last decade, however, stable carbon and nitrogen isotope ratio analysis has also been applied for the reconstruction of Byzantine breastfeeding and weaning practices. This paper reviews the documentary evidence for Byzantine weaning and compares it to isotopic data for eight Greek Byzantine skeletal samples from the sites of Eleutherna, Kastella, Messene, Sourtara, Stylos, Nemea, Petras and Servia (6th–15th centuries AD). The documentary evidence suggests that Byzantine children were weaned at a relatively late age. The age patterning of the stable isotope data is not as clear as normally seen at single sites. However, the presence of a higher proportion of elevated values in juveniles aged three years or less suggests that weaning was completed by the fourth year—a pattern consistent with the written sources. The data available from this study allow us to make some tentative suggestions about cultural and temporal differences in weaning, and to recommend directions for further research. A comparison of the Byzantine data presented here to data published for Roman-era sites from the Mediterranean and Western Europe suggests that the Byzantines maintained a Roman-era practice of relatively late weaning. In contrast, medieval data for Western Europe and the few measurements made on post-Byzantine Greek material suggest more variation, with some groups weaning late and others weaning earlier, by two years of age.  相似文献   

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Abstract

It was always clear that for practical reasons any new region-based study of the Roman and Byzantine periods in north-western Jordan would have to rely on existing evidence from archaeological surveys and excavations. The concentration of previous archaeological survey work in parts of the region of West Irbid in Jordan, and especially the surveys made by N. Glueck in the 1940s and S. Mittmann in the 1960s, made this area especially attractive for archaeologists. In this paper, the aim was to analyze the results of the West Irbid survey, particularly of the Roman and Byzantine periods, made during September 2005. The information gathered was of great help, enabling the classifi cation of sites into groups according to the nature of occupation, and analyzing the discovered architectural remains to provide a broader context for interpretation of the nature of Roman and Byzantine settlements in the surveyed region.  相似文献   

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In west‐central Neuquén Province, Argentina, in the area around Estancia Llamuco, west of Zapala, south of Las Lajas and north‐east of Lago Aluminé, there are multiple primary and secondary sources of obsidian. Primary sources occur within the south‐east extension of the Plio‐Quaternary volcanic chain that runs from Copahue volcano through Pino Hachado. Secondary sources include river‐bed gravels within the valleys of Arroyo Cochicó Grande and Río Kilca as far south as where this river joins with Río Aluminé, and the Quaternary fluvial–glacial sediments cut by the valley of Río Covunco as far east as Portada Covunco. Visually variable obsidians from these two secondary sources include homogeneous black and grey‐translucent types, porphyritic and banded types, and an abundant quantity of oxidized red and black obsidian. However, all these visually distinct obsidians have similar and unique chemistry, with Ba between 220 and 340 ppm, different from any other obsidians previously reported from Neuquén, which all have Ba > 500 ppm, as do obsidians from sources to the north in Mendoza and to the west in Chile. This chemical distinctive obsidian has been exploited and transported over a wide area, beginning prior to 4000 bp , and occurs in local archaeological sites, as well as sites ≥ 300 km to the north‐east in La Pampa Province, ~430 km to the south in Chubut Province, and >75 km to the west across the Andean drainage divide in Chile.  相似文献   

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Abstract

Greek lexicography of the Byzantine period is a thorny subject, indeed an almost thankless task, if efforts end merely in a collection of inaccessible and unpublished handwritten' material. I would like to call to mind the case of Emmanuel Miller in the last century, who showed a continuous interest in lexicography, pouring out new Greek words in the notes to his editions on every occasion. However, those notes are nothing but feeble shadows of his vast collection left to the Bibliotheque Nationale de Paris about ninety years ago. When I inspected this mass of more than 40,000 small slips, I was considerably taken aback, in view of the fact that this collection as well as every other similar to it (for instance the 10,000 Athesaurista gathered by Pezopoulos) are practically of no use for Byzantine studies, since they have never been published.  相似文献   

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In this study, the skeleton of an approximately 15‐year‐old child, dating back to the Late Byzantine period (13th century AD) is examined with the aim of determining where this specimen fits in the continuing arguments on the origins of syphilis. It was unearthed during an excavation at an amphitheatre in Nicaea dating to the Roman period. The Nicaea specimen displays common symptoms found in the majority of people with congenital syphilis such as Hutchinson's incisor, mulberry molar, darkened enamel, radial scar on frontal bone, sabre tibia, syphilitic dactylitis, and gummatous and non‐gummatous osteomyelitis on almost every post‐cranial bone. Because of the sub‐periosteal new bone formation, the medullary spaces in some long bones are narrowed or completely obliterated. These lesions, which were observed via macroscopic and radiological examination, reflect the late stages of congenital syphilis. The specimen, when examined together with increasing numbers of other finds from the Old World, contributes to the argument that venereal syphilis did exist in the Old World before 1493, and brings forward the need to revise the Columbian hypothesis, which maintains that syphilis is a new disease carried to the Old World from the New World by Columbus' crew. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

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Samples of table and cooking ware, dating back to the Byzantine period of the ancient Greek colony of Cuma, were analysed by optical microscopy, X‐ray diffraction, X‐ray fluorescence and scanning electron microscopy, in order to reconstruct the main technological properties of these manufactures. The comparison of minero‐petrographical data from these samples with those of some kiln wastes allowed us to hypothesize a local manufacture for most of the investigated specimens and to confirm the relative reference groups. A restricted number of samples did not link with the main groups, indicating a regional (or maybe extra‐regional) production, in agreement with the widespread circulation of this high‐medieval ceramic production in southern Italy.  相似文献   

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