Search results for "CONST"
showing 10 items of 7706 documents
Experimental characterization of a novel configuration of thermoelectric refrigerator with integrated finned heat pipes
2021
Abstract Thermoelectric refrigerating systems (TER) are environment-friendly technologies. They have several advantages such as low maintenance costs, are less cumbersome and long lifetime. However, these systems have low coefficient of performance and are limited in achieving low temperature levels. This study investigates a new configuration of TE refrigerator employing a novel arrangement of heat sinks with integrated flat and finned heat pipes. A mathematical model is firstly developed to predict transient temperatures and cooling limit time. An experimental characterization is then performed and it includes optimization of energy consumption, cooling time, temperature levels and TE ref…
Evaluation of building heating loads with dimensional analysis: Application of the Buckingham π theorem
2017
Abstract A detailed assessment of building energy performance requires a large amount of input data concerning building typology, environmental conditions, envelope thermophysical properties, geometry, control strategies, and several other parameters. Notwithstanding, the use of specialized software tools poses many challenges in regards to the retrieval of reliable and detailed information, setting a steep learning curve for engineers and energy managers. To speed up the preliminary assessment phase, it might be more convenient to resort to a simplified model that allows the evaluation of heating energy demand with a good level of accuracy and without excessive computational cost or user e…
2D slab models of TiO2 nanotubes for simulation of water adsorption: Validation over a diameter range
2020
Financial support provided by Scientific Research Project for Students and Young Researchers Nr. SJZ/2019/2 realized at the Institute of Solid State Physics, University of Latvia is greatly acknowledged. Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under Grant Agreement No. 739508, project CAMART 2 .
Effect of material and geometric parameters on natural convection heat transfer over an eccentric annular-finned tube
2019
In this work, the performance of an eccentric annular finned tube heat exchanger under natural convection conditions has been investigated numerically. The objective of the study is to analyse the ...
Dynamics of Polymer Melts above the Glass Transition: Monte Carlo Studies of the Bond Fluctuation Model
1997
The bond fluctuation model on the simple cubic lattice with a bond-length dependent potential energy favoring long bonds exhibits a glassy freezing in as the temperature is lowered, many properties being qualitatively similar to experiment. The present paper studies the dynamical properties of the model (as they result from the random hopping algorithm), using configurations of undercooled polymer melts that have been carefully equilibrated by the slithering snake algorithm. In this way quantitatively reliable data can be obtained for distinctly lower temperatures than in the previous work on the dynamics of this model that used the random hopping algorithm for equilibration as well. If var…
Introducing teachers to new semiotic tools for writing instruction and writing assessment: consequences for students’ writing proficiency
2017
This article reports consequences for student writing quality based on a long-term professional learning project. Project teachers, representing all school subjects in grades 3–7, were presented with a writing construct, ‘Wheel of Writing’, and norms of expectation for writing proficiency. Participating teachers used the writing construct and norms as a basis for writing instruction and writing assessment. The project was conducted in 24 schools across Norway. 3088 students from 20 project schools participated. Two hundred and thirty three students from 4 schools were used as a comparison group. The investigation showed that students in primary school improved their writing quality signific…
Gendered Use of the Hedge in Academic Discourse
2013
This paper discusses the distribution of hedges in academic texts in relation to the gender of the writer. The assumption prior to the analysis concerned possible differences in communicative practices between male and female writers reflected in the hedging of their propositions. The textual material covers 20 research articles, 10 written by male and 10 by female authors, published in the Journal of Linguistics in the years 2001–2010. Metadiscourse as “discourse about discourse” is connected with the communicative, social and personal involvement (Hyland 2000). Hedges, as indicators of the writer’s stance, should reveal characteristics of particular writing styles based on powerful or sup…
Mechanism of Antibacterial Activity via Morphology Change of α-AgVO3: Theoretical and Experimental Insights
2017
The electronic configuration, morphology, optical features, and antibacterial activity of metastable α-AgVO3 crystals have been discussed by a conciliation and association of the results acquired by experimental procedures and first-principles calculations. The α-AgVO3 powders were synthesized using a coprecipitation method at 10, 20, and 30 °C. By using a Wulff construction for all relevant low-index surfaces [(100), (010), (001), (110), (011), (101), and (111)], the fine-tuning of the desired morphologies can be achieved by controlling the values of the surface energies, thereby lending a microscopic understanding to the experimental results. The as-synthesized α-AgVO3 crystals display a …
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…
Large 256-Pixel X-ray Transition-Edge Sensor Arrays With Mo/TiW/Cu Trilayers
2015
We describe the fabrication and electrical characterization of 256-pixel X-ray transition-edge sensor (TES) arrays intended for materials analysis applications. The processing is done on 6-in wafers, providing capabilities on a commercial scale. TES films were novel proximity coupled Mo/TiW/Cu trilayers, where the thin TiW layer in between aims to improve the stability of the devices by preventing unwanted effects such as Mo/Cu interdiffusion. The absorber elements were electrodeposited gold of thickness 2 μm. The single-pixel design discussed here is the so-called Corbino geometry. Most design goals were successfully met, such as the critical temperature, thermal time constant, and transit…