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The Akko 1 shipwreck was found in 4 m of water inside the ancient harbour of Akko, Israel, and was fully recorded under water. Several hull‐components were retrieved and documented on land, as well as all the finds. The results of the archaeological research and the study of the historical background suggest that the Akko 1 shipwreck is the remains of an eastern Mediterranean naval auxiliary brig, built at the end of the first quarter of the 19th century, and sailing under the Egyptian flag. The ship was apparently wrecked during the 1840 naval bombardment of Akko. © 2012 The Authors  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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Geostationary satellites provide measurements over a wider geographical area with high temporal sampling, while microwave measurements are more accurate but sparse. For continuous monitoring of the Indian monsoon, geostationary platform would be ideal. In this study, INSAT (Indian National Satellite) Multi‐spectral Rainfall Algorithm (IMSRA) has been used for the estimation of rainfall from Kalpana‐1 very high resolution radiometer (VHRR) measurements. IMSRA benefits from the relative advantages of infrared and microwave sensors and is operational at the India Meteorological Department (IMD). In this paper, rainfall is estimated over India at meteorological sub‐divisional scale during the south‐west monsoon season of 2009 using Kalpana‐1 satellite measurements. This is the first experimental attempt to generate meteorological sub‐divisional scale rainfall maps using Kalpana‐1 satellite measurements. The rainfall maps for the south‐west monsoon season over the Indian land region are successfully utilised as a space input for the drought monitoring of the year 2009. The results have been compared with the IMD gauge‐based accumulated rainfall maps at monthly and seasonal time scales. The qualitative comparison suggests that rainfall maps generated using the present methodology is in good agreement with the IMD rainfall maps. The quantitative comparison of the sub‐divisional monthly accumulated rainfall shows a correlation of 0.77 and standard error of 71 mm over the non‐orographic regions, whereas a correlation of 0.60 and standard error of 117 mm is observed over the orographic regions. The present study shows that Kalpana‐1 satellite‐based rainfall estimates (IMSRA technique) can act as a complementary tool for the monsoon monitoring over the Indian meteorological sub‐divisions and can be used for various meteorological and hydrological applications.  相似文献   

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Whereas scholars have often described the material interests served by any given social group's selective narration of history, this article catches scholars in the act of selectively narrating Yorùbá‐Atlantic cultural history in the service of their own faraway activist projects. Anthropologist Ruth Landes' re‐casting of the Afro‐Brazilian Candomblá religion as an instance of primitive matriarchy not only encouraged feminists abroad but also led Brazilian nationalist power‐brokers to marginalise the male, and often reputedly homosexual, priests who give the lie to Landes's interpretation. In the service of a longdistance Yorùbá nationalist agenda, sociologist Oyeronke Oyewumi has declared traditional Yorùbá society ‘genderless’, and found, among both North American feminist scholars and Yorùbá male scholars, allies in concealing the copious evidence of gender and gender inequality in Yorùbá cultural history. What these historical constructions lack in truth value they make up for in their power to mobilise new communities and alliances around the defence of a shared secret. The article addresses how politically tendentious scholarship on gender has inspired new social hierarchies and boundaries through the truths that some high‐profile scholars have chosen to silence.  相似文献   

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Introducing a new theoretical category in religious studies, “ritual practice of time,” this essay constitutes an analysis about rituals of the structure of space and time of the Aztec fifty‐two‐year calendar in Mesoamerica. Time and space, completed and exhausted at the termination of the fifty‐two‐year cycle, had to be symbolically renewed and recreated in a fifty‐two‐year ritual. Challenging the view held by numerous Mesoamericanists, I demonstrate that the ritual practice of time of the related 365‐day calendar (“New Year ritual”) was not spatio‐temporal in a horizontal quadripartite manner. Given that only one world or cardinal direction of the world was ritually observed, a symbolic re‐enactment of the creation myth could not be executed since it would take four consecutive “New Year rituals” of four years to symbolically define the quadripartite earth. Conversely, the fifty‐two‐year ritual (and the 260‐day ritual) could, in principle, have this very significant meaning and function.  相似文献   

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As part of a research project on medieval trade and maritime transportation in the former Norwegian province of Bohuslän, western Sweden, a dendrochronological analysis of the so‐called Mollö cog was undertaken. The wreck, which was first salvaged in 1980, was previously dated by 14C analysis. Since this provided a nearly 400‐year time‐span for the building of the vessel, a more precise dating was considered essential. In conjunction with dendrochronological sampling, several features not previously reported were recorded. This paper presents the find, the research history and the results of the dendrochronological investigation. © 2012 The Authors  相似文献   

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Thermally re‐equilibrated fluid inclusions are reported in natural fissure quartz (qtz1) from polymineralic veins in the diagenetic‐anchizonal clastic sedimentary rocks of the Ciñera‐Matallana coal basin (Variscan, NW Spain). Euhedral quartz formed during early fissure opening from an immiscible fluid mixture composed of a low salinity aqueous solution and a CH4‐rich vapour phase, at temperatures of about 110–120°C and pressures ranging from 15 to 56 MPa. Five textural types of re‐equilibration are recognised in progressive order of inclusion modification: scalloped, hairy, annular‐ring shaped, haloes and decrepitation clusters. These textures resulted from a combination of brittle fracturing and dissolution and re‐precipitation of quartz, with preferential loss of water. The thermal peak was short‐lived, but was high enough to induce extensive decrepitation of fluid inclusions in vein quartz throughout the entire basin. Enhanced temperatures can be related to the intrusion of diorites in the basin. Careful analysis of textural features in fluid inclusions from diagenetic and very low‐grade metamorphism environments constitutes a useful tool for recording basin thermal history.  相似文献   

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ABSTRACT This article provides some reflections on borderwork derived from social anthropological research with Indigenous people in south‐eastern Australia (S.E. Australia). In post‐settler states, borderwork traverses a range of fields—employment, health, education and politics. It engages both Indigenous and the non‐Indigenous who grapple with the issues associated with socially and culturally liminal spaces. Borderwork provides a focus on the way boundaries are continually constructed as well as dismantled and reconstructed as a result of historical, political and social change. The article draws upon the work of Bourdieu (2000) to interrogate the ‘naturalisation’ of conditions that give rise to particular interpretive frameworks and the specific relations of power that legitimate one interpretive framework over others. ‘First Nations people are border workers by the nature of their aboriginal claims and their persisting marginalization…’ (Celia Haig‐Brown, 1992:230)  相似文献   

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Clashes over the status of West Papua and the political future of the territory proliferated markedly following the end of Indonesia's New Order regime in 1998. Amid a wide variety of demands for justice and independence, and a series of demonstrations, mass gatherings and prayers, only a few Papuans mused on how Papua could become a state and what would constitute its nature as being distinctly Papuan and/or Melanesian. One exception is the work put into the Constitution for West Papua entitled Basic Guidelines, State of West Papua, a document edited by Don A.L. Flassy, a bureaucrat, writer and thinker, with a preface by late Theys H. Eluay, then chairman of the Papuan Council. In this article I analyse this Constitution to show how a combination of Christianity and local customs, and a mimicry of elements of Indonesian nation building and symbols of the Indonesian nation‐state are reshaped to oppose Indonesian nation‐building agendas. The Constitution shows that when Papuans imagine an independent state, forms of vernacular legality play a central role. ‘The state’ has journeyed to Papua and encouraged faith in ‘the law,’ and Basic Guidelines is partly the effect of this growing vernacular legality. My analysis shows that it is essential to see how legal mobilisations and imaginations of the state articulate with other normative systems and practices – in particular Christianity and custom (adat) – and how they mutually allow for and invite strategies.  相似文献   

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