COMPUTING NUMERICAL IMAGES OF STUDENT WRITING: PERSPECTIVES FROM EDUCATIONAL RESEARCH

With the rapid increase in the number of available digital texts in schools, new methodological approaches to studying writing development in education are now emerging. However, with new methodological approaches follow new epistemological challenges. In this article, I examine some of these challenges and discuss how they affect the role of computational linguistics within the field of educational writing research. The article is structured around three main sections. First, I position computational linguistics within the wider field of educational writing research with particular focus on L1 writing and K12 education. Second, I discuss to what extent methods from computational linguistics can provide us with new insights into different aspects of educational writing. Third, I discuss the potential of the concept of affordance to bridge between technology-centered and human-centered methodological approaches, and I relate this idea to recent theoretical developments in the digital humanities. Based on this discussion, I conclude the article with suggestions for possible directions in future writing research

Noise Effects In Capillary Tubes Caused By Refrigerant Flow

The preferred cooling process for household refrigeration appliances is a vapor compression refrigeration process with a capillary tube as expansion device. The vapor compression refrigeration system requires a phase change of the refrigerant inside the condenser and evaporator. Through a direct connection of condenser outlet and capillary tube inlet, which is commonly practiced for household refrigeration cycles, the condenser outlet defines directly the refrigerant state at the capillary tube inlet. Due to unsteady operation conditions the refrigerant state can change from subcooled liquid to saturated liquid with partially a vapor phase at the capillary tube inlet. The refrigerant flow inside the capillary tube is either adiabatic or non-adiabatic (by utilizing internal heat exchange). In both cases the refrigerants state changes during the expansion with an increase of vapor quality towards the capillary tube outlet. A variable vapor quality at the capillary tube inlet causes different flow patterns, especially at the capillary tube outlet. These flow patterns change periodically depending on the refrigerant state at the capillary tube inlet. Associated with the periodical changing flow patterns the occurrence of noise effects with the same periodicity and remarkable variations of the sound pressure level can be observed at the capillary tube outlet. Â This paper presents the experimental investigations on the simultaneous occurrence of refrigerant flow patterns and corresponding noise effects at the outlet of a capillary tube installed in a refrigeration test cycle. The discussion of the experimental results leads to an explanation of causal relation between distinguishable flow patterns and corresponding noise effects

Introduction: The Role of Computational Methods within the Humanities and Social Sciences

Introductio

Experimental and numerical investigations on full-scale adhesively bonded timber trusses

Timber architecture, taking advantage of modern production techniques, is increasingly moving towards free forms; however, traditional joining techniques are not yet adapted to echo the new expression at the level of the details. This paper reports on adhesively bonded joints as a way to help architects fully unleash their creative potential. For this purpose, experimental and numerical investigations on full-scale adhesively bonded timber trusses were performed, in which adhesive bonds were compared to traditional doweled connections. The adhesively bonded trusses achieved significantly higher failure load and stiffness. Tests on small clear specimens were conducted to determine input parameters for finite element analyses. The sole timber connection was characterised, giving valuable insights into the mechanical behaviour of this truss component. At this end, the influence of the embedded length of the applied sleet plates was experimentally determined, delivering data to benchmark the subsequent dimensioning method. The trusses were then modeled and excellent agreement was found between numerical and experimental results. Finally, a dimensioning method, based on a realistic multi-axial failure criterion coupled with size effects was implemented and yielded very good agreement when with experimental results. The reported investigation demonstrates the high potential of adhesive bonding in timber structure

Experimental and numerical analyses of full-span floors and component level subassemblies for robust design of CLT floors

Tall mass timber structures are becoming increasingly prevalent and, with some now rising as tall as 81m (Abrahamsen, 2017) it is vital to consider design for structural robustness and disproportionate and progressive collapse prevention under accidental actions (Starossek & Haberland, 2012). The Eurocode 1-7 approach (European Committee for Standardization, 2006) focuses on material independent objective-based design. An inherent robustness through alternative load paths (ALPs), primarily catenary action, is targeted through introduction of vertical and horizontal ties. This is a prescriptive approach without the necessary physical basis when introducing novel construction methods

Energy Saving Potential of a Temperature Test Chamber by implementing a Heat-Pump

Energy savings become more and more important – also for the rather small industry sector of environmental simulation. So far the technical focus was mainly to realize challenging test cycles which are often gives as temperature profiles. The energy efficiency of the test devices are not specified by any standard. Nevertheless, especially test cycles with intermittent cooling and heating over a wide temperature range need a substantial electrical energy input. As state-of-the-art technology for cooling a vapor compression cycle and for heating an electrical heater is used. In this work a standard temperature test chamber with a specified temperature range from -75 °C to 180 °C using a cascade cooling system and an electric heater is investigated. As a first step the baseline chamber was investigated experimentally and the energy consumption quantified. In the next step the refrigeration cycle was modified with a heat pump capability as well as further cycle modification that indicated energy saving potential in preliminary studies. A comparison to the baseline chamber is carried and reveals substantial energy saving potential