一种结构对称的破碎青铜文物的数字修复方法

为有效解决结构具有对称性的破碎文物的数字修复问题,本研究利用计算机技术,提出了一种针对结构具有对称性的破碎青铜器文物的数字修复方法。首先利用三维激光扫描仪实现破碎文物的三维建模,然后采用基于特征点集的最小二乘方法计算破碎文物的对称平面,进而利用对称性实现破碎文物的数字修复。针对对称性计算的镜像模型与原始模型几何造型不完全一致的问题,采用非刚性配准方法实现了镜像模型的几何变形。实验结果表明,本方法能够实现破碎文物的数字修复,将为实体修复提供借鉴和指导。     

Flake selection and scraper retouch probability: an alternative model for explaining Middle Paleolithic assemblage retouch variability

It has been proposed that the relative abundance of retouched objects in Paleolithic assemblages can serve as a measure for artifact transport and by extension a proxy for site occupation duration. This approach is based on the assumption that retouch represents curatory effort for extending the service time of transported artifacts when raw material access is uncertain or limited, a condition that could arise when groups move frequently over long distances across the landscape. This paper proposes an alternative model that explains retouch as a probabilistic outcome of an expedient, on-site flake selection process. A simulation illustrates that the model is capable of producing assemblage retouch configurations akin to those commonly observed in Paleolithic settings. The simulation also indicates that the threshold applied by past individuals for selecting particular artifacts is an important parameter for explaining assemblage retouch variability. Using artifact weight as a proxy for flake selection criteria, several Middle Paleolithic assemblages exhibit patterns that support predictions made from the model simulation. Findings suggest that variation in scraper frequency among the studied assemblages can be accounted for by an interaction between the abundance of artifact production events and shifting artifact selection criteria, without appealing to higher-level behaviors of technological and mobility strategies.     

Experimental examination of animal trampling effects on artifact movement in dry and water saturated substrates: a test case from South India

This paper presents the motivation, procedures, and results of an experiment that examines short episodes of animal trampling in dry and water saturated substrates in South India. While horizontal artifact displacement was similar to that modeled by other trampling experiments, vertical artifact displacement in water saturated substrates was greater than any reported experiment to date. The toolstone used in this experiment, a silicious limestone, exhibited minimal damage after trampling. Artifact inclination patterning appeared to be a potentially diagnostic middle-range marker of trampling in water saturated substrates. Given the abundant number of Paleolithic sites that are located on flat, open surfaces near water-bodies, or experience monsoonal climatic regimes, we propose that future excavations should measure artifact inclination on a regular basis.     

The Structural and Functional Complexity of Hunter-Gatherer Technology

The complexity of hunter-gatherer technology has been measured by counting artifact parts or production steps. There are a variety of alternative approaches to the measurement of artifact or system complexity. If technological complexity is assumed to reflect the complexity of the problem (or amount of entropy reduction) that the artifact is designed to address, the most appropriate measure of technological complexity is functional design complexity, which entails application of the entropy formula from information theory to the making and using of an artifact and the results obtained by its use. Functional complexity is related to structural or hierarchical complexity, because the entropy formula can be represented as a hierarchy (or step-by-step reduction of entropy) and the functional differentiation is related to the structural differentiation of an artifact. Another approach to hunter-gatherer technological complexity entails definition of a class of “complex artifacts” on the basis of general design characteristics (e.g., incorporation of moving parts). The most structurally and functionally complex artifacts are those that possess multiple states, either through changes in the physical relationship between parts (or sub-parts) during use or through structural differentiation. Although functional complexity is difficult to measure, structural or hierarchical complexity may be measured—and multiple-state artifacts may be counted—with adequate ethnographic and archaeological data on hunter-gatherer technology.     

A Twenty-First Century Archaeology of Stone Artifacts

Archaeologists today, as in the past, continue to divide their stone artifact assemblages into categories and to give privilege to certain of these categories over others. Retouched tools and particular core forms, for instance, are thought to contain more information than the unretouched flakes and flake fragments. This reflects the assumption that information to be gained from stone artifacts is present within the artifact itself. This study evaluates a continued interest in the final form of stone artifacts by first considering ethnographic accounts of stone artifact manufacture and use in Australia and then by utilizing the patterns observed in these accounts to investigate assemblage patterning within an Australian archaeological case study. Reading the ethnographic accounts provides no indication that Aboriginal people valued more or less complex artifacts, in uniform ways, in every situation. In fact, the opposite is true. Stone artifacts were always valued in some sense but which ones, and in which ways, depended on the situations the people who needed the artifacts found themselves in. Aboriginal people were quite capable of making and using expedient and informal artifacts in complex ways. The significance of these observations is considered for stone artifact studies in general and in relation to a case study from western New South Wales, Australia.     

Virtual Representation: the Production of 3D Digital Artifacts

As new digital technologies now pervade the discipline of archaeology, the practice of creating digital 3D representations of artifacts has become widespread. The rapid growth and acceptance of these technologies into the discipline leaves us in a position where we must engage with how these tools fit our epistemologies. I propose that we look to a much older technology, photography, to inform the way that these digital artifacts are dealt with as we move into an increasingly digital field. In doing so, I will argue that the creation of a 3D digital artifact is a productive process, just as any form of media used to document and interpret the archaeological record. Through this production, the digital form is decoupled from the original physical artifact. The creation of a new representation of the artifact (in the form of a photograph or digital model) provides a new dimension to our interactions with these artifacts. The result of the digital movement in archaeology is a more interactive experience with artifacts, allowing researchers and the public alike digital access to archaeological collections. If the current trend continues, digital artifact modeling will become as indispensable to archaeology as traditional photography. It is therefore necessary for archaeologists to be aware of the subjectivities and biases that exist during this productive act as we move into a more integrated field of digital, representational technologies.     

To Preserve the Struggle: Digitizing the Oregon Trail

Historical Archaeology - The Oregon Trail is an ephemeral artifact of great importance to the history of the United States. While there is a great deal of historical documentation in the way of...     

Economic and Land-Use Implications of Prehistoric Fire-Cracked-Rock Piles,Northern Arizona

Abstract

Intensive archaeological survey of 14.5 sq km of the Upper Basin, an area located near the Grand Canyon's eastern South Rim in northern Arizona, has discovered 126 fire-cracked-rock piles that are surrounded by artifact scatters of varying size and assemblage composition. Because these phenomena are unprecedented in upland conifer ecosystems of the American Southwest, several hypotheses are explored regarding their formation histories. Analyses of artifact assemblages, botanical remains, pollen, and faunal remains recovered from four excavated sites indicate that they result from flaked-stone artifact production, ground-stone artifact reuse and recycling, ceramic-vessel-fragment recycling, and animal and plant processing. In addition, radiocarbon dates and temporally diagnostic projectile-points and ceramics imply that the sites differ in terms of frequency, intensity, and patterns of use, and with respect to the groups of people who formed them (Anasazi, Cohonina, Havasupai, or Hopi). Byproducts of a little-known, long-term land-use pattern in Southwestern prehistory (ca. A.D. 417–1650), these sites represent a key source of information for understanding how different sources of variability come to be expressed in archaeological landscapes.     

The Potential Relationship Between Archaeological Artifact Exposure and Surface Geomorphic Processes: Northeastern Peloponnese,Greece

Complex interactions between topography, near-surface geology, active tectonics, climate, and human activity shape a landscape, conditioning archaeological deposits and making sediment deposits from surface erosion important archives. There is a potential relationship between the intensity of geomorphic processes and surface artifact distribution. This study assesses the potential relationship between soil erosion by water and the spatial distribution of archaeological surface artifacts in the Inachos River watershed, Greece. The mountainous, semi-arid Mediterranean region is particularly vulnerable to soil loss. Soil erosion is quantified by applying the Revised Universal Soil Loss Equation in a GIS framework. Estimates of soil loss vary spatially compared to surface artifact finds of the pedestrian survey of the Western Argolid Regional Project. A statistically significant relationship is identified between surface erosion rates and artifact density. Preferential topography for occupation suggests this is an associative rather than causative relationship. Knowledgeable interpretation of artifact distribution enables accurate reconstruction of human settlement history.     

Accumulations research: Problems and prospects for estimating site occupation span

Accumulations research examines the dynamic relationship among artifact discard, duration of occupation, and population size. The history of accumulations research is reviewed, emphasizing studies that use accumulation rates to measure site occupation span. Ethnoarchaeological and experimental research demonstrates that cooking pots are an ideal artifact type for accumulations research. Data from the Duckfoot site in southwestern Colorado are used to develop an annual accumulation rate of cooking pot sherds for households. This rate is used, along with population estimates and estimates of the total cooking pot sherd accumulation, to determine the occupation span of five sites located in the nearby Dolores River valley.     

Differential diagnosis of a prehistoric biological object from the Koster (Illinois) Site

This paper details the differential diagnosis of a biological artifact recovered from a burial within the Koster Middle Archaic site in Illinois. The burial was excavated from the Middle Archaic 3, Helton Phase component (∼5800–4900 BP). The artifact was a calcified nodule of unequivocal biological origin recovered from the pelvic region of an adult (50+ years) female. Morphological and radiographic analysis of the object resulted in the consideration of 19 possible diagnoses; all but four could be eliminated. Possible interpretations of the object as a lithopaedion, calcified lymph node, amputated ovary or simple ovarian cyst are examined in detail. Of these, calcified lymph node or amputated ovary remain most probable. Copyright © 2003 John Wiley & Sons, Ltd.     

Multivariate visualization and analysis of photomapped artifact scatters

Simultaneous analysis of relationships between multiple artifact classes is required for characterization of many types of activity areas. This paper illustrates improved forms of multivariate visualization, spatial analysis and integration of experimental results that are possible with GIS based photomapping. Techniques are demonstrated through analysis of a hearth associated artifact scatter exposed during excavations of a Late Archaic pithouse at Jiskairumoko, Peru. A multivariate density raster is created and additive color visualization is used for simultaneous display of three artifact distributions. Performing unconstrained clustering in a GIS, space is classified by simultaneous relative density relationships between multiple object types.     

Integrating pattern and context in spatial archaeology

Traditional approaches to intrasite spatial analysis in archaeology have concentrated on identifying associations among classes of artifacts over a site surface. This focus has tended to ignore the possible effects of contextual constraints on inter-class relationships, for example the “gravity effects” of hearth features on object deposition. Consequently, sets of co-occurring artifact classes defined in space are usually ascribed behavioural significance as “tool kits”, even though they may represent unrelated objects simply discarded into the same spatial location. This paper attempts to illustrate this problem through contextual integration of artifact and feature distributions. Quantitative methods are employed to carry out contextual spatial analysis of artifact distributions from the Upper Palaeolithic rockshelter site Le Flageolet I (Dordogne, France). Results indicate that associations among artifact classes in space might be constrained by feature locations at Le Flageolet I and that contextual interpretations are warranted for the observed inter-class relations.     

Developing a Landscape History as Part of a Survey Strategy: A Critique of Current Settlement System Approaches based on Case Studies from Western New South Wales,Australia

In Australia, geomorphological change since the late nineteenth century ensures surface artifact visibility but the contribution of full coverage regional survey to an understanding of past landscape use is limited by the lack of easily datable artifacts. Here, we describe a multi-stage survey strategy based around intensive archaeological, geomorphological and chronological studies as an alternative to traditional site-based approaches. We view the formation of the archaeological record as a sedimentary process and use a geomorphological approach to understand the history of landscape use from surface artifact scatters. We pay particular attention to recording datasets with reference to the timescales over which they have accumulated, and we discuss the types of behavioral inferences that can be drawn from the results of intensive survey, illustrated using the results from our western New South Wales research.     

Making a Mountain Out of a Molehill? A Low-Cost and Time-Efficient Molehill Survey of the Lost Medieval Harbor Site of Monnikerede,Belgium

Grasslands pose a particular problem for archaeological survey involving artifact assessment, as no material is plowed up to the surface. Although finds in molehills are often the only source of information available on sites with such low visibility, an archaeology of molehills has thus far been largely disregarded. Yet, by applying a low-cost and time-efficient methodology, both the potential and the pitfalls of molehill archaeology come to the forefront. At the medieval harbor site of Monnikerede, it was possible to assess material culture and to locate certain structural elements. However, when artifact densities were compared with the underlying geophysical anomalies, a more complex relationship appeared at the level of individual features.     

试论文物摄影的表现方法

文物摄影是摄影艺术的一个门类 ,除了要注重科学性和真实性外 ,还要强调其艺术性和欣赏性。本文从拍摄角度、背景处理、光线运用等几个方面论述了文物摄影的表现方法。     

Raw material quality and Oldowan hominin toolstone preferences: evidence from Kanjera South,Kenya

The role of raw material quality in Oldowan technology has not been fully explored. There are numerous studies suggesting Oldowan hominins preferred certain types of stone for artifact manufacture. Previous studies of the artifact assemblage from the early Pliocene Oldowan locality of Kanjera South (South Rachuonyo District, Kenya) show that raw material selection and transport was an important aspect of Late Pliocene hominin adaptations. Yet the exact properties of stones that hominins were selecting remain enigmatic. Two potentially important features of artifact raw material are durability and fracture predictability. We investigate fracture predictability through mechanical tests of stone and investigations of the affect of stone properties on fracture patterns in archaeological collections. We investigate stone durability with actualistic studies of edge attrition combined with further mechanical tests of various lithologies. Oldowan hominins at Kanjera appear to have selected raw materials based on their durability. The ability for a stone to fracture consistently does not appear to be as important in hominin toolstone preference as previously assumed. Hominins that produced the assemblages at Kanjera South appear to have incorporated an extensive understanding of various attributes of raw material in the transport and production of stone artifacts. When combined with previous research on the transport patterns at Kanjera, the results of this study provide evidence for a more complex raw material acquisition strategy than has previously been suggested for Late Pliocene Oldowan hominins.     

Investigating absence: Assessing the cumulative effects of casual collecting at a 19th century Bahamian plantation

Abstract

Recent archaeological work at Prospect Hill, a 19th century plantation in the Bahamas, revealed artifact patterns that are inconsistent with expectations for a plantation site. The quantity and quality of artifacts in residential areas associated with the planter family and the enslaved population were inverted and suggest significant post abandonment changes. The site of Prospect Hill has been a destination for tourists and student groups since the mid-20th century, and the areas of the site most accessible to these visitors are also those with surprisingly low artifact counts. I investigated the possibility that regular visitation involved casual collecting using historical data as well as artifact assemblages from archaeological work at Prospect Hill. My analysis suggests that the archaeological record has been altered significantly through casual, opportunistic collecting, and it offers insights for identifying casual collecting elsewhere.     

The recognition of multiple spatial patterns: a case study from the French upper paleolithic

A pattern recognition approach to spatial analysis is applied to artifact distributions from the Magdalenian site of Pincevent, Section 36. Patterning is investigated using a κ-means cluster analysis that permits iterative mapping of artifact distributions at several scales of spatial complexity. Multiple scales of patterning are recognized in the Pincevent distributions. These patterns are assessed in terms of those discovered by the excavators through intensive visual inspection of the materials. Basic concordance is seen between these two approaches. Finally, the analysis detects more detailed patterning. A relationship between artifact abundance and location seems to hold constant throughout the site.