Showing papers by "University of Applied Sciences, Mainz published in 2004"

3d scanning and photogrammetry for heritage recording: a comparison

Abstract: There is a high demand in documentation of cultural heritage objects such as artifacts, sculptures or buildings. In the past years, laser scanning, or 3D scanning in general, has been used increasingly for cultural heritage recording and the question arose if this new method can replace traditional methods like close-range photogrammetry. To investigate the advantages and disadvantages of both methods, i3mainz has carried out some case studies for cultural heritage documentation. Different typical objects were chosen and characteristical parts of them were recorded both by photogrammetry and scanning. Documented objects include an archaeological stone wall, baroque relief plates, Stone Age artifacts, ancient statues and the facade of a classical castle. Besides 3D scanning all these examplary objects were also recorded with standard stereophotogrammetry which is the most popular heritage recording method so far. Results are usually line drawings, but the creation of orthophotos or digital surface models is possible, too. In this paper five case studies are shortly introduced and the results of both measurement techniques are presented and compared. The aim is to give users (especially those who are not surveying experts) recommendations, which method is suited best for what kind of application, or even if a combination of 3D scanning and photogrammetry is advisable. Criteria like quality of the results, amount of cost and time, required equipment and occurring problems are to be considered.

How will Basel II affect bank lending to emerging markets? An analysis based on German bank level data

Abstract: This paper investigates whether the new Basel Accord will induce a change in bank lending to emerging markets using a comprehensive new data set on German banks` foreign exposure. We test two interlinked hypotheses on the conditions under which the change in the regulatory capital would leave lending flows unaffected. This would be the case if (i) the new regulatory capital requirement remains below the economic capital and (ii) banks' economic capital to emerging markets already adequately reflects risk. On both accounts the evidence indicates that the new Basel Accord should have a limited effect on lending to emerging markets.

Recording and visualization of the cenotaph of german emperor maximilian i

Abstract: The Hofkirche in Innsbruck, Austria, with its tomb of German Emperor Maximilian I is one of the most famous and outstanding historical monuments in Central Europe. For centuries the Cenotaph (i.e. empty tomb) was separated from the visitors by a black iron lattice. In addition, the fine caved marble plates were covered by glass. Because of a basic restoration of the tomb, lattice and glass plates were removed for the first time ever since its construction in the 16 century. For a short period in May 2002 all sides were accessible after the temporary housing of the restoration technicians had been removed from one side and not yet been moved to the other side for the second restoration period. This could be used for a complete metric documentation of the object. Both, close-range photogrammetry and 3D scanning techniques were used. Photogrammetric images consisted of stereo pairs and separate color images. 3D scanning was accomplished with a MENSI S25 laser scanner for the overall structures and a GOM ATOS II structured light scanner at high resolution for the relief plates. Fig. 1: Overview model of the cenotaph derived from scanned data * Corresponding author. Different methods can be used to visualize the meshed surface model. Line plots from the photogrammetric stereo models do not really give an adequate representation of this object. 3D visualization using the scanning results can achieve a much better impression of the complicated geometry after data modeling, error correction, and filling in remaining ‘holes’. In order to model the complex geometry, it is necessary to use huge amounts of data. The model in its highest resolution consists of more than 1.000.000.000 triangles. Because of restrictions in the hardand software presently available, the high resolution model has to be processed and stored in more than 140 separate virtual models. The project proves the enormous potential of these new technologies, but shows as well that more progress is needed in hardware and software development to accomplish such demanding tasks. An attempt was made to convert the meshed 3D models to 2D vector drawings, similar to those resulting from traditional plotting using photogrammetric stereo models. Solutions could be found to select all object outlines and all edge areas where curvature shows high absolute values. On the other hand, for other “lines” (e.g. the details of a human face) where a stereo plotter operator will draw lines on his own intuition, no obvious mathematical definitions could be found.

Path Dependence of the General Price Level: A Value Theoretic Analysis

Abstract: The paper examines path dependence of price indexes, a problem that has become acute after international adoption of chain indexes for price and volume changes in the SNA93. Path dependence is an old issue of index numbers, and has been in the way of using chain indexes ever since their invention. The paper accepts chaining at its start, and tries to develop a sound deflation procedure from there. In this analysis path dependence is less an issue of appropriate formalization of a given concept, the traditional approach in index number theory, but rather a problem of developing an interpretation to a given and now worldwide recommended statistical practice. The key issue is found in the fact that money is not only the standard means of payment, concerning central banks, but also the standard of value in an economy, a feature that bears directly on the compilation of price indexes and national accounts. As a result, a chained weighted index is shown to be path independent, if it is interpreted as a change not of prices, but of the unit of account in which prices are expressed.

Path dependence of the general price level: A value theoretic analysis

Abstract: The paper examines path dependence of price indexes, a problem that has become acute after international adoption of chain indexes for price and volume changes in the SNA93. Path dependence is an old issue of index numbers, and has been in the way of using chain indexes ever since their invention. The paper accepts chaining at its start, and tries to develop a sound deflation procedure from there. In this analysis path dependence is less an issue of appropriate formalization of a given concept, the traditional approach in index number theory, but rather a problem of developing an interpretation to a given and now worldwide recommended statistical practice. The key issue is found in the fact that money is not only the standard means of payment, concerning central banks, but also the standard of value in an economy, a feature that bears directly on the compilation of price indexes and national accounts. As a result, a chained weighted index is shown to be path independent, if it is interpreted as a change not of prices, but of the unit of account in which prices are expressed.

A Tool for Supporting Graphical Interactive Assessment

Abstract: Online-Assessment is widely accepted both for self-assessment and also as the basis for examinations. However its potential has not been fully utilized in current systems. Good instruments for innovative assessment are e.g. modern graphics based questions. Unfortunately their production is still very time and cost intensive. The GIA project develops a framework, which provides a solution that enhances the process of “authoring, providing and evaluation” of graphics based questionnaires. A new kind of question templates skeleton was developed in order to enable easy as well as time and cost reduced authoring of highly interactive graphical questionnaires. Moreover an innovative approach for fully automatic evaluation of the graphical questions was embedded in the new templates. Various graphical question templates were developed and tested in different kind of questionnaires – even in different domains, e.g. surveying as well as in medical education.

TARGET: a flexible installation for inspection of industrial objects

Abstract: A solution for industrial inspection purposes will be shown. The conception is based on digital colour images taken from numerous perspectives around the object to be controlled. The process of image orientation is simplified and improved by the use of spatial reference objects. In contrast to conventional planar targets they are visible from all views and allow a better concatenation of the images. In addition, they can introduce a scale information what simplifies preparatory actions to be done within object space and can contribute with their spatial shape. For the inspection the object will be marked by a laser projection system with point or line patterns. The main aspects of the solution will be shown together with first test results.