京都大学 / 新制・課程博士 / 博士(工学) / 甲第25258号 / 工博第5217号 / 新制||工||1995(附属図書館) / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 杉浦 邦征, 教授 八木 知己, 教授 KIM Chul-Woo / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

The European Parliment stipulated regulations concerning the forestry vehicles operators' health and working conditions. The allowed whole body vibrations were limited, which influenced the design of the vehicles' cabin. Surveys show a strong correlation between operator's comport and their productivity. The object of the research was Rottne AB Comfort Line Cabin, which was designed to increase the comfort for the forwarder operators. The main objective was to determine the cab's inertia properties, position of the centre of gravity and the resonance frequencies of the cab as well as a system consisting of the cab and its suspension. The methods used were an impact test with Mass-Line Analysis for the cab's properties and Operational Modal Analysis for the system. For both tests a Leuven Measurement System was used, but a part of the calculations were made in parallel by use of a MATLAB code written for this thesis. In addition a suspension test was made to estimate the centre of gravity and it was here treated as the reference value. The authors used reference values and the quality of the obtained results to compare the methods used. Further proposals for future research were made together with hints how to use vibration tests more effectively.

In this thesis a methodology for measuring vibrations has been produced andinvestigated for APID 60, a rotorcraft in a Vertical Take-off and landing remotelypiloted aircraft system (VTOL RPAS). A comparative study was carried out forthe purpose of identifying the methodology with respect to design modificationscommon to the APID 60. The pilot-study identified experimental modal analysis(EMA) as a feasible part of the methodology for experimentally extracting themodal parameters of a structure. The EMA was performed on the main frameof the APID 60 where an impact hammer test was chosen as the technique forextracting the response data. As a comparison a point mass was added to thestructure to alter the dynamic properties and the test was repeated.The results from the EMA was compared with a modal analysis performednumerically with a calculation software. Comparison of the results from EMAwith the modal analysis performed numerically indicates consistency. This confirmsa good reliability of the methodology produced. However, the structure onwhich the test were preformed is simple in terms of constant structural properties.Further work should therefore investigate whether this methodology of measuringvibrations could be successfully applied to a structure with higher complexity.

Blockfields as an indicator of landscape development with a specific microclimate is presented in many scientific publications. This diploma thesis is focused on finding the relationship between the hardness of stone blocks and the intake of potential radiation, with an assessment of morphology, location and local conditions. Within the selected study areas in Northern Bohemia was recorded a total of 73 blockfields, of which 22 sites were selected for further investigation. From the results of the statistical analyses was shown the relationship between the income potential of radiation and the degree of ventilation of stone blocks. The analyses also show the relationship between the hardness of stone blocks in the blockfields and the orientation of the blockfields to the world's sides, which proved to be significant. The tests performed by the analyses of each third (high) stone seas have shown the possibility of moving rock blocks downhill.

The diploma thesis deals with non-destructive testing of concrete as well as with the relationship between determined parameters and the compressive strength of concrete. The thesis is mainly focused on the ultrasonic pulse velocity method and the rebound hammer test. The experimental part of the thesis describes non-destructive tests performed on concrete blocks. The compressive strength was tested on the drill cores taken from the concrete blocks. The aim of this thesis is to find regression models of the relationship between the compressive strength and non-destructive parameters, and the subsequent analysis of the results.

This thesis deals with the rebound hammer method as a tool for approximation of the time limit for handling the concrete. The theoretical part is focused on three fields of knowledge - rebound hammer test, production of precast concrete components and statistical data analysis. The following practical part deals with the design of two single-parameter linear functions for two types of rebound hammer testers - SilverSchmidt L and SchmidtOriginal N. Statistical data processing is completed by the analysis of influential points by using the Cook’s distance. The resulting statistical models are compared with commonly used relationships.