Search results for "technical"

Saturated Soil Hydraulic Conductivity

2016

This chapter deals primarily with field measurement of saturated soil hydraulic conductivity, K fs . Well or borehole permeameter techniques, specifically developed for subsurface soil measurements above the water table, are initially illustrated. Particular attention is paid to establishment of steady flow under constant head in an uncased borehole, widely developed both theoretically and experimentally in the last 30 years. Situations involving cased boreholes, transient flow, or falling head processes are then described. These variants have received a renewed interest in the last few years. New data analysis procedures have been proposed and this circumstance allows us to obtain subsurfa…

Closure to "experimental Modeling of Submerged Pivot Weir" by M. Bijankhan and V. Ferro

2021

This paper is a Closure to “Experimental Modeling of Submerged Pivot Weir”.

Erratum for “Experimental Modeling of Submerged Pivot Weir” by M. Bijankhan and V. Ferro

2020

Poļu studentu korporācijas Welecja piemiņas plāksne

2020

Raksts satur informāciju par poļu studentu korporāciju Welecja piemiņas plāksni, kas glabājās LU Muzeja krājumā. Rakstā tiek analizēta piemiņas plāksnes memoriālā nozīme kopīgajā Polijas un Latvijas valstu vēsturē, uzsverot poļu studentu korporāciju aizsākumus Baltijā. Uzmanības centrā ir Welecja korporants Ignācijas Moscickis, kurš studējis ir Rīgas Politehnikumā/Rīgas Politehniskajā institūtā, kā arī sniedzis ieguldījumu demokrātijas saglabāšanas mēģinājumā Polijas valstī.

The First Decades of Independence – White Finland

2019

The Republic of Finland was established after a bloody civil war between the Reds and the Whites in 1918. This chapter analyses the emergence of Finnish independence and the role higher education played in the new republic in the 1920s and 1930s. During this period, the University of Helsinki was Finland’s dominant higher education institution, even though one public pedagogical college and seven private higher education institutions were also established: two universities (one Swedish-speaking and one Finnish-speaking), three business schools, a technical university, and a higher education institution of social sciences.

Optimizing and Modeling the drying process of the Natural Gas through the Taguchi method

2018

The aim of this study is to highlight the optimization method of the drying process of natural gas, using the Taguchi method. The natural gas undergoes several stages from its extraction until reaching its end consumer. As the natural gas contains several impurities and a certain quantity of water and vapors, the drying process is very important to obtain a product of high quality. Gas dehydration can be obtained through several methods, the method presented here being the absorption method - by use of a drying station with triglycol. This method is considered to be the most convenient one taking into account the obtained results. Nevertheless, cost reducing is the main objective for compan…

Modelling heat transfer-controlled cooling and freezing times: a comparison between computational values and experimental results

2013

Modelling of heat transfer-controlled cooling and freezing time predictions are very important for a good preservation of foodstuffs. In that regard, we used a computer code based on the finite-element method that allowed us to analyse the phase-change of various foodstuffs during their freezing. The model was exercised to predict process times. The results can be used to design high efficiency plants. In this work, the results predicted by the FEM program are compared with the experimental values given in technical literature.

Application of cohesive-zone models to delamination behaviour of composite material

2012

International audience; The parameters of cohesive elements have to be chosen correctly in the simulation of composite delamination by finite element method: such as interface strength, interface stiffness and shape of cohesive law. The purpose of this work is to investigate their influence on the accuracy of the results obtained. A three-dimensional cohesive-zone model has been established using Ls-dyna to simulate Double-Cantilever-Beam mode I (DCB) and Edge-Notched-Flexure mode II (ENF) tests. The influence of these parameters of cohesive element on the maximum load and the slope of load-displacement curve have been discussed by comparing experimental and numerical results. Four traction…

Non-uniform Sediment Transport Estimation in Non-equilibrium Situations: Case Studies

2014

Abstract Quantitative estimate of sediment transport in alluvial channels is one of the most important task in river engineering. Even today, numerical models of sediment transport processes are confronted with some difficulties, often of conceptual nature. One of these difficulties is the simulation of non-uniform sediment transport in non-equilibrium situations, which requires the characterization of the ability of the alluvial system to immediately overcome the variations of the sediment boundary conditions. In this work a 1-D numerical model, which includes a new expression of the so-called “adaptation coefficient”, has been applied to test its capability to simulate the transient bed p…

Reclaimed asphalt test specimen preparation assisted by image analysis

2015

This paper presents a laboratory investigation aimed at establishing a protocol for the production of homogeneous asphalt mixtures test specimens, incorporating reclaimed asphalt by using a gyratory compactor with coring and trimming works. Stone mastic asphalt specimens were compacted at the previously identified target densities with the final aim of obtaining specimens with a fixed and homogeneous air void distribution. A microstructural study was conducted to characterize the homogeneity in the air void distribution using X-ray computed tomography (CT) combined with image analysis techniques. The study concluded that the gyratory compactor is suitable for producing homogeneous test spec…