Search results for "technical"
showing 10 items of 955 documents
A Proposal to Model Ancient Silk Weaving Techniques and Extracting Information from Digital Imagery - Ongoing Results of the SILKNOW Project
2019
Three dimensional (3D) virtual representations of the internal structure of textiles are of interest for a variety of purposes related to fashion, industry, education or other areas. The modeling of ancient weaving techniques is relevant to understand and preserve our heritage, both tangible and intangible. However, ancient techniques cannot be reproduced with standard approaches, which usually are aligned with the characteristics of modern, mechanical looms. The aim of this paper is to propose a mathematical modelling of ancient weaving techniques by means of matrices in order to be easily mapped to a virtual 3D representation. The work focuses on ancient silk textiles, ranging from the 15…
Latvijas Universitātes vēsturiskais studentu karceris
2021
The University of Latvia has 19 th-century historical witness regarding the daily life of students during studies - the historical student solitary confinement cell. The origins of the student solitary confinement cell are found in medieval Germany, when universities were entitled to detain students into cells for the misdeeds during the studies. The idea was realized in the 19th century, which coincided with the time when German academic influence spread in the Baltics. During the occupation of the USSR, this history phenomenon was forgotten or distorted, but it is now rehabilitated. The Museum of the University of Latvia with the University of Latvia Academic Press has issued booklet, whi…
Historical University of Latvia student solitary confinement cell: video
2021
The University of Latvia has 19th-century historical witness regarding the daily life of students during studies - the historical student solitary confinement cell. The origins of the student solitary confinement cell are found in medieval Germany, when universities were entitled to turn students into cells for the misdeeds during the studies. The idea was realized in the 19th century, which coincided with the time when German academic influence spread in the Baltics. During the occupation of the USSR, this history phenomenon was forgotten or distorted, but it is now rehabilitated. The Museum of the University of Latvia has filmed a video with subtitles in English about the student solitary…
The Contribution of Technological Change on EU's Exports
2013
Abstract The competitiveness of European countries is a constant concern in an environment dominated by the globalization of markets. Export competitiveness is an important dimension of a country's competitiveness. On top of that, in support to competitiveness, innovation is considered as a strong variable according to the Schumpeterian framework. This paper explores the relationship between technological change and international trade according to the OECD technological classification and the United Nations International System of Industrial Classification third revision for the 2 and 3 digit divisions of the manufacturing sector industry. An exploratory analysis is carried out on four Eur…
A Comparative Study of Soil Suction Measurement Using Two Different High-Range Psychrometers
2007
An extensive experimental study was performed to compare the measurement capabilities within different ranges of two total suction measurement equipment: SMI transistor psychrometers and a chilled-mirror dew-point psychrometer (WP4 Dewpoint PotentiaMeter). The equipment were used in a systematic way to determine the relative humidity of the environment surrounding different compacted clayey soils along drying paths and covering a wide total suction range (0.1 to 70 MPa). The equipment description and the calibration protocols followed are presented, as well as suggestions regarding the improvement of their performance. The water retention curves of two different compacted clayey soils are p…
Mechanical behaviour of compacted scaly clay during cyclic controlled-suction testing
2007
Scaly clays are stiff and highly fissured soils due to their complex geological history. Owing to these characteristics, they may be placed and compacted as excavated, to obtain a material with adequate engineering properties, suitable as core material in earth dams and in waste isolation fills. With reference to these engineering applications, an exhaustive experimental programme is developed to characterise the hydro-mechanical behaviour of this compacted material under a variety of controlled-suction paths. This paper presents selected test results, focusing on the interpretation of specific behavioural features of the volume change of this complex material; namely, the strain accumulati…
Hydraulic Characterization of a Pervious Concrete for Deep Draining Trenches
2018
Reduction in pore water pressure is an useful strategy to improve the stability of slopes. Deep draining trenches can be used for this purpose. For the realization of deep trenches, the usual conventional construction techniques are not adequate and the use of adjacent vertical panels, built by means of the methods well-established for diaphragm walls, is necessary. However, unbonded materials (i.e., gravels) cannot be used, because the excavation of a panel adjacent to one already built will cause instability. For this scope a bonded material such as pervious concrete can be used. It must have high permeability; filtering capacity, in order to prevent internal erosion of the soil in which …
Volumetric Behaviour of Lime Treated High Plasticity Clay Subjected to Suction Controlled Drying and Wetting Cycles
2017
The paper presents some experimental results collected on samples recovered from an experimental embankment obtained by compacting a lime-treated clay. Samples were collected soon after the in situ compaction and they were cured in controlled environmental conditions for at least 18 months. Mercury intrusion porosimetry tests (MIP) were carried out on freeze-dried specimens to characterize the microstructure of the material. In order to assess the durability of the improved material, laboratory tests focused on the effects of cyclic variations of the degree of saturation on the water retention properties and the volumetric behaviour of the stabilized clay. Collected results show that the li…
Stress path dependence of hydromechanical behaviour of compacted scaly clay in wetting and drying suction controlled oedometer tests at constant vert…
2008
The results are presented of an experimental programme devoted to investigating the volumetric strain and water ratio (volume of water to volume of solids) evolution of a compacted scaly clay stressed by wetting and drying cycles in suction-controlled oedometer tests. The stress paths applied included loading and unloading cycles at constant matric suction and suction controlled wetting-drying cycles at constant vertical net stress. The test results show that during wetting and drying cycles the samples experienced irreversible shrinkage or swelling strains depending on the stress path applied. Irreversible water ratio increases were always observed in these cycles. However, a quasi-reversi…
Volume change behaviour of a compacted scaly clay during cyclic suction changes
2010
The research presented in this paper focuses on the investigation and modelling of the volume change response of compacted tectonised clay samples subjected to several wetting and drying cycles in controlled-suction oedometers. Oedometer tests were carried out under different values of constant vertical net stress, and wetting and drying cycles were performed varying applied matric suction between 10 and 800 kPa. The investigation was complemented with a study of the material microstructure to support the interpretation of the overall mechanical response. At a microscopic level, the material is characterized by different types of particle assemblages, scales, and clay aggregates. One of th…