Galilei als Methodologe

Galileo did not develop a systematic methodology but rather a methodical form which represents an essential part of the development of modern scientific thought. Keywords to the methodical form of Galileo's thought are: 1) The geometrization of the sciences (‘mathematization of nature’) - this refers especially to the explication of the methodological priority of a theory of measurement. 2) Argomento ex suppositione, that is, the coupling of the originally proof-theoretical distinction between analysis and synthesis to elements of a methodology of empirical science. 3) The axiomatic structure of mechanics that corresponds to the modern semantic theory conception and to constructivist conceptions of the philosophy of science. 4) A constructive (or instrumental) concept of experience, which replaces the Aristotelian concept of a phenomenal experience in the construction of physics.     

A High-Performance Quadrilateral Flat Shell Element for Seismic Collapse Simulation of Tall Buildings and Its Implementation in OpenSees

Shear walls are important lateral force-resistant components of tall buildings. Hence, a reliable numerical model that can accurately represent the mechanical characteristics and large deformations of shear walls is critical for realistic collapse simulation of tall buildings. Based on the theory of generalized conforming element, a high-performance quadrilateral flat shell element, NLDKGQ, accounting for the large deformation using the updated Lagrangian formulation, is proposed herein and implemented in OpenSees. The reliability of NLDKGQ is validated using classical benchmark problems and reinforced concrete specimens. In addition, its capability in simulating the collapse of a tall building is also demonstrated.     

DEM Algorithm for Progressive Collapse Simulation of Single-Layer Reticulated Domes under Multi-Support Excitation

In this paper, the Member Discrete Element Method (MDEM) is modified and perfected for three aspects: the algorithm itself, loading and computational efficiency, and to accurately and quantitatively simulate the progressive collapse for large-span spatial steel structures. In addition, the corresponding computational programs are compiled. First, from the perspective of the method, a meshing principle for discrete element models is determined, a treatment for material nonlinearity and strain rate effect is proposed, and a damping model is established. Next, the Displacement Method is introduced to determine the multi-support excitation for the MDEM, and then motion equations of particles under multi-support excitation are derived. On this basis, the specific process of gravitational field loading is presented. Furthermore, parallel implementation strategies for the MDEM based on OpenMP are constructed. Finally, the collapse simulation of a 1/3.5-scaled single-layer reticulated dome shaking table test model under multi-support excitation is carried out. The comparison demonstrates that the ultimate load and failure mode as well as the complete collapse time of the numerical results are consistent with the experimentally measured responses, and the configuration variations from member buckling and local depression until collapse failure are fully captured. Moreover, the displacement time-history curves obtained using MDEM are almost identical to the experimental measurements, and there is a nuance only in the amplitude. It is verified that MDEM is capable of precisely addressing the collapse failure for large-span spatial steel structures. Additionally, the failure mechanism for structures of this type is naturally revealed.     

Where were the hearths: an experimental investigation of the archaeological signature of prehistoric fire technology in the alluvial gravels of the Southern Plains

The interpretation that a rock has been subjected to cultural utilization is a basic element of hunter-gatherer research. The fracture mechanics of the flaked stone tool production process are well understood and the material residues are routinely identified during fieldwork. Conversely, non-percussion processes such as hot-rock technology, which can result in rock fracture, are less well understood. An experimental study has been developed to examine the fractured gravels observed at a prehistoric site on the Southern Plains (USA). The experiment has sought to determine whether cultural or natural agencies were responsible for the production of the angularly fractured rocks. The positive results of the experiment indicate that not only were humans most likely responsible for the breakages, but also that the fractured rocks often exhibit distinctive morphologies that may be identified during fieldwork. This simple experimental methodology is applicable to other hunter-gatherer sites where the depositional environment is not conducive to the structural preservation of features such as hearths.     

Fotografie als Wissenschaft

Photography as Science: In 1908 the English physicist Arthur Mason Worthington published A Study of Splashes, a treatise on the physical behaviour of falling drops. The photographic experiments were performed by means of an electric spark „in absolute darkness”︁. Worthington's experimental practice dealt with two different areas of knowledge production: an area the operator could perceive control from the outside and a corresponding black-box where the photographic recording itself took place. The paper discusses the epistemic challenges of this specific shift from imperceptible events to their photographic representations. It shows to what extent the information revealed by the photographic apparatus had to be converted, for it did not speak for itself. Thus, Worthington's work went beyond the classical dichotomy between objectivity and imagination.     

计算机辅助设计（CAD）在文物修复中的运用

通过计算机辅助设计(CAD)在文物修复这门传统工艺中的运用,进一步提高了在文物修复过程中预想修复效果和制定最佳修复方案的精确性。并借助计算机辅助设计在二维平面、三维立体效果方面的特长,模拟文物破损处复原、去除和保留不同颜色物质、创建和复制器物残缺部分及预览器物安装情况等效果。这样不仅为文物修复提供有利帮助,还使这门传统工艺与当今先进计算机技术得到有机结合。修复实践表明,对那些变形较大,又不想进行破坏性修复的文物来说,三维模拟修复就是唯一的修复方法。     

In a nutshell: the identification and archaeological application of experimentally defined correlates of Macrozamia seed processing

This paper describes the methods and results of ethnographically-based replicative seed processing experiments conducted on Australian Macrozamia moorei seeds. Archaeological evidence indicates that these seeds were consumed by Australian hunter–gatherers in both the Pleistocene and Holocene. The experiments identified three features indicative of human processing and tested the effect of different processing variables (striking position, indentor type, thermal modification and presence of outer flesh) on the frequency of these diagnostic criteria. The results demonstrate that it is possible to use the physical modifications on individual seed specimens to identify the anthropogenic fracture of seeds and specific methods used to process them. These criteria were used in the analysis of M. moorei seeds from mid-Holocene-aged archaeological sites in central Queensland, Australia. The results indicate that seeds with and without sarcotesta were processed using a wooden indentor via side striking techniques.     

西安鼓楼油饰彩画主要病害分析

为了对油饰彩画进行科学保护,对具有代表性的西安鼓楼油饰彩画病害进行了调查分析．发现存在的主要病害有失光、褪变色、粉化、龟裂、起甲、脱落、烟熏、降尘等。结合实验室模拟实验对病害成因进行了初步探讨,认为导致病变的内因是木基层含水率及地仗制作工艺;外界环境因素为紫外线、温湿度、大气降尘、油烟熏及降雨等。分析结果可为彩画保护提供科学依据。     

Täuschend ähnlich – Bemerkungen zur Geschichte des Modellexperiments

Deceptively Similar. Remarks on the History of Model Experiments. The article argues for a reconsideration of what has been called ‘model experiments’ or ‘mimetic experiments’. After providing a short overview of the historical developments and the occurences of such types of experiments, three aspects pertaining to their practical functions are discussed. First, the aspect of control: Model experiments are often employed to get a grasp on phenomena that are otherwise beyond the control of human actors. Second, their aesthetic dimension: Model experiments often employ aesthetic strategies that, far from being epistemic obstacles, establish their function as models and may generate new areas of research. Third, meta‐theories: The practice of experimenting on models is often accompanied by discussions about their representativeness. Albeit triggered by problems in local contexts, this self‐reflective discourse did acquire a more general relevance with the formulation of scaling laws in the 19th century.