On Theme and Variation

Abstract

The ways in which the author, the sculptor Peter Randall-Page, has made use of the ideas of D’Arcy Thompson are described. How Thompson showed that commonalities of form and pattern exist across the biological and abiotic realms is described, and the implications that physical constraints limit and sometimes dominate the capabilities of evolutionary natural selection are explored. Since we evolved in a world shaped in this manner, the likelihood that this palette of forms is one that carries strong psychological meanings and associations is examined, and the ways in which these forms are a rich source of inspiration and allusion for visual artists are discussed, hinting at the play of opposing tendencies, the dance between order and randomness, and the ways in which nature can derive variations on a theme.     

From Hand Survey to 3D Laser Scanning: A Discussion for Non-Technical Users of Heritage Documentation

Abstract

Digital technology has changed our approaches to cultural heritage documentation radically and promises to continue to bring rapid changes. Photographic and non-photographic (graphic) documentation tools are merging in one process, in which digital photographic technology is the main base. Due to digital technology, there is an increasing gap between specialist technicians and non-technical users involved in heritage documentation. 3D approaches are still not popular among users in cultural heritage. However, in order to build a bridge between the specialist and non-technical users, a dialogue between them needs to be developed, not only to discuss issues of data precision and 3D accuracy, but also visualization production systems, which can now easily be achieved by modern digital photographic technology.

This paper presents a comparative evaluation and synthesis of cultural heritage documentation methods and survey techniques currently available, focusing on the needs and requirements of non-technical users of heritage documentation. It attempts to clarify some new aspects in cultural heritage documentation and to assess the impact of current technology. The paper undertakes a comparative evaluation of the potential application of digital methods in documentation — and examines issues such as quality, accuracy, time, costs and specific skills required — from pre-electronic techniques (hand measurement) to 3D laser scanning, which today represents the most advanced technology available for measuring and documenting objects, structures and landscapes.     

3D Digital Documentation,Assessment, and Damage Quantifi cation of the Al-Deir Monument in the Ancient City of Petra,Jordan

Abstract

The rock-cut monuments in the ancient city of Petra in Jordan form an outstanding tangible heritage site. Unfortunately, this important part of the world's cultural heritage is gradually being diminished due to weathering and erosion problems. In this research, an approach combining in situ surveying and laboratory analysis is applied in order to provide sufficient and comprehensive data regarding the documentation and evaluation of the status of the Al-Deir monument in Petra. The purpose was not only to quantify the damage, but also to make a first step towards creating a 3D monitoring programme of the deterioration rate. The approach presents a correlation study between the environmental condition and the surface weathering damage, using 2D mapping of the weathering form and accurate 3D realistic modelling from laser scanning and digital photogrammetry. The 2D mapping provides detailed weathering damage information for the entire stone surface of the monument, whereas the 3D modelling provides information on the spatial distribution and texture of the damage. Additionally, the 3D digital model can provide reference data as an exact guide to the restoration needed. In order to support the visual presentation of 3D surface details, a hybrid approach combining data from laser scanning and digital imagery was developed.

Studies of stone texture and spatial distribution of soluble salts were carried out at the monument in order to explain the mechanism of the weathering problem. Relative humidity, temperature, and wind are the main factors in the salt damage process. In order to study the effect of these conditions in the salt crystallization process a series of fieldwork investigations and laboratory work were undertaken. The results show that visible zoning of weathering damage is correlated to different salt concentrations.     

The Tel Akko Total Archaeology Project (Akko,Israel): Assessing the suitability of multi-scale 3D field recording in archaeology

Abstract

Archaeology is a destructive discipline, and, unfortunately, the majority of methods employed by archaeologists to record and preserve the archaeological record consist of two-dimensional representations of three-dimensional (3D) subjects. Recent breakthroughs in 3D technology, however, have the potential to revolutionize the discipline. In recent years, multiple software suites capable of generating spatially accurate, photorealistic 3D models with a series of digital photographs have become available. Following a successful season of field testing in 2011, the Tel Akko Total Archaeology Project (Akko, Israel) expanded the use of Agisoft’s PhotoScan Pro—one of the commercially available software suites—to test the accuracy and suitability of the program for archaeological applications at multiple scales. After two years of field testing, it is clear that the implementation of PhotoScan Pro in archaeology facilitates unprecedented accuracy in field recording and digital heritage management, and provides a new outlet for the dissemination of archaeological data.     

The 4th-century B.C. shipwreck at Mazotos,Cyprus: New techniques and methodologies in the 3D mapping of shipwreck excavations

Abstract

Well preserved ancient shipwrecks are rare in the archaeological record, but when discovered, they can provide valuable information on a wide range of research issues if analyzed and documented properly. In this paper we discuss the significance, potential, and constraints of mapping methods applied during the underwater excavation of shipwreck sites with special emphasis on stratigraphy, documentation of finds, and reconstruction of site formation processes. As a case study, we present the digital photogrammetry and computer vision software programs used in the excavation of the 4th-century b.c. shipwreck at Mazotos, Cyprus. Our goal is to develop a targeted documentation and mapping method of ongoing shipwreck excavations so that others can address complex research questions concerning this unique discipline of archaeology.     

Restoration of paintings on domes with non-developable geometry (Los Santos Juanes Church in Valencia)

The restoration of paintings on elements in cultural heritage buildings (fundamentally, churches) involves two structural problems: capturing the geometry of the construction element and its development. In many cases, the geometries are regular (e.g., cylinders, spheres, elliptical domes). However, there are cases in which the elements cannot be adapted to any known geometry, much less one that can be mathematically developed. The development of surfaces becomes essential for the restoration of paintings over “flat elements” (over which work is performed on the ground) that are subsequently transferred to the real surface (ceilings). The mathematical transformations that allow regular geometries to be developed are widely known (cartographic projections). However, when the geometry is irregular, there is no development. This study presents a new methodology based on differential rectification and its application for the development of oculi in the Los Santos Juanes Church (Valencia), whose geometry is completely irregular both in shape and as a result of construction defects (and damage caused by fire). The present study focuses on the restoration of paintings damaged by fire.     

唐陵大遗址考古的思路与方法——2007～2008年度中国田野考古一等奖获奖项目介绍

<正>陕西唐陵大遗址保护项目的考古工作荣获2007～2008年度全国田野考古一等奖。这是国家文物局和考古学界对我们工作成绩的肯定与鼓励,也是我院田野考古工作者开拓创新、辛勤工作的结果。以下将唐陵考古工作中的思路、方法、措施以及得失作以介绍,以期得到考古界同仁的指教。     

T.H. Green and the Dissidence of Dissent: On Religion and National Character in Nineteenth‐Century England

Thomas Hill Green (1836–82) has been widely recognized for his contributions to Liberal political‐social theory and for his Liberal partisanship. Historians and political theorists continue to emphasize his advocacy of limited state interference and democratic localism, as well as his anti‐imperialist statements. Recent scholars of English nationalism, national identity and patriotism, including Peter Mandler, Julia Stapleton, Krishan Kumar, H.S. Jones, Roberto Romani and Georgios Varouxakis, acknowledge Green as an acolyte of Giuseppe Mazzini, a Cobdenite and a Little Englander. While they place Green's ideas within a continuum of Victorian Liberal nationalist ideas (blending into Conservatism and socialism during the 20th century), their investigations foster the view that Green placed little value in the nation as a focus of individual and collective identification. In their readings of Green, the abstract ‘community’, free of national peculiarities, was to him the antidote to both individual and national narrowness. However, examination of Green's statements about community, the moral ideal and religion reveals that his theorising was informed by a view of national character different from that of most contemporary liberal intellectuals. Green rejected the ‘Liberal anglican’ view that a national church or clerisy was necessary to guide the development of the English nation. He identified ideas and practices of protestant dissenters as progressive forces in English history and endorsed them as means of national development. Religious pluralism and forms of ecclesiastical organisation promoting democratic localism were to Green among the essential characteristics of Englishness.     

Use of ground penetrating radar to map subsurface archaeological features in an urban area

The ground penetrating radar (GPR) technique was used to investigate the subsurface in an urban area located in Mesagne (Italy) to obtain a map of the archaeological features in the ground. The GPR survey was undertaken at selected locations placed near (about 50 m) to a necropolis dating from the Messapian to the Roman imperial age, using a GSSI Sir System 2 incorporating 200 and 500 MHz centre frequency antennae. The selected areas (A and B) were surveyed along parallel 1 m spaced profiles using a 200 MHz antenna in area A and along parallel 0.5 m spaced profiles using a 500 MHz antenna in area B. For the selected areas the processed data were visualised in 3D space not only by means of the standard time slice technique, but also by means of a recently proposed approach, namely by iso-amplitude surfaces of the complex trace amplitude. The immediacy in revealing the spatial positioning of highly reflecting bodies, such as the anomaly interpreted as an old hypogeum room in area A, makes 3D visualisation techniques very attractive in archaeological applications of GPR. Their sensitivity to the signal/noise ratio is, on the other hand, highlighted by the quite poor performance in area B, where the only reliable result provided by all the techniques was the ancient living surface reflection, whereas none of them could effectively enhance the visibility of weak hyperbola reflections noted on 2D sections and probably related to the walls located on the ancient living surface. The performance of the various techniques in these two different situations allowed insights into their main advantages and drawbacks to be gained.     

罗斯福新政时期美国文官政治化倾向的加强

新政时期,罗斯福总统在扩大政府规模的过程中,通过“政治庇护制”任命文官,使行政部门特别是行政部门中的“政治文官”以多种方式直接参与立法和政策的制订,自主地执行联邦政府的政策,导致美国文官政治化倾向的加强。这种现象不仅源于政治与行政的特殊关系,源于“政治文官”自身的优势,也源于美国特殊的政治体制和社会结构。