An image-based visual strategy for working with color contrasts during design

acceptedVersio

Are Split Tablet Keyboards Better? A Study of Soft Keyboard Layout and Hand Posture

acceptedVersio

Quantification of eDNA to map the distribution of cold-water coral reefs

An effective management of vulnerable marine ecosystems is dependent on thorough knowledge of their location. Multibeam bathymetric mapping and targeted remotely operated vehicle (ROV) surveys are currently used to map areas impacted by industrial activities when vulnerable species are expected. However, multibeam bathymetric mapping is not always a possibility and surveying large areas using ROVs is expensive. Here, we developed a species-specific eDNA assay targeting a 178 bp fragment in the control region of the mitochondrial DNA of the cold-water coral (CWC) Lophelia pertusa. The aim was to test if concentrations of L. pertusa eDNA in seawater, determined using droplet digital PCR (ddPCR) technology, could be used to assess the broad scale distribution of CWCs in a region, to supplement multibeam mapping and direct targeted ROV surveys. Our assay successfully amplified L. pertusa DNA from seawater. In laboratory we documented an exponential decay rate of the targeted DNA fragment and a linear correlation between coral biomass and eDNA concentrations in flow through microcosms. The ability of the method to detect CWC reefs in situ was tested in the fjords south of Bergen, Norway, where such reefs are common. We tested five sites with, and five sites without, known reefs. Lophelia pertusa eDNA was detected in all 10 sites. However, concentrations were elevated by 5 to 10 times in water sampled off the two large reefs growing on vertical surfaces. Water sampled 10 m above CWC reefs growing on the flat seabed did not produce an equally clear eDNA signal, nor did single CWC colonies growing on vertical surfaces. Treating the eDNA as a passive particle with no active vertical or horizontal movement, we successfully modeled the dispersal of eDNA from the known CWC reefs in the region and achieved a good fit with measured eDNA concentrations. In all, our study demonstrated a great potential for eDNA measurements as a cost-efficient tool for a rapid screening of the broad scale distribution of CWC reefs growing on vertical surfaces (so called wall reefs) that cannot be imaged using traditional ship mounted downward looking multibeam echo-sounders and difficult to detect using ROVs alone.publishedVersio

Frictional fluid instabilities shaped by viscous forces

Multiphase flows involving granular materials are complex and prone to pattern formation caused by competing mechanical and hydrodynamic interactions. Here we study the interplay between granular bulldozing and the stabilising effect of viscous pressure gradients in the invading fluid. Injection of aqueous solutions into layers of dry, hydrophobic grains represent a viscously stable scenario where we observe a transition from growth of a single frictional finger to simultaneous growth of multiple fingers as viscous forces are increased. The pattern is made more compact by the internal viscous pressure gradient, ultimately resulting in a fully stabilised front of frictional fingers advancing as a radial spoke pattern

A Recent Impact Origin of Saturn’s Rings and Mid-sized Moons

We simulate the collision of precursor icy moons analogous to Dione and Rhea as a possible origin for Saturn's remarkably young rings. Such an event could have been triggered a few hundred million years ago by resonant instabilities in a previous satellite system. Using high-resolution smoothed particle hydrodynamics simulations, we find that this kind of impact can produce a wide distribution of massive objects and scatter material throughout the system. This includes the direct placement of pure-ice ejecta onto orbits that enter Saturn's Roche limit, which could form or rejuvenate rings. In addition, fragments and debris of rock and ice totaling more than the mass of Enceladus can be placed onto highly eccentric orbits that would intersect with any precursor moons orbiting in the vicinity of Mimas, Enceladus, or Tethys. This could prompt further disruption and facilitate a collisional cascade to distribute more debris for potential ring formation, the re-formation of the present-day moons, and evolution into an eventual cratering population of planetocentric impactors

Improved measurement technique for the characterization of organic and inorganic phase change materials using the T-history method

In the past decade, the interest in phase change materials (PCMs) has grown significantly due to their ability to store large amounts of thermal energy in relatively small temperature intervals. Accurate knowledge of thermo-physical properties is a prerequisite for any reliable utilization of these materials. The T-history method is widely used for the investigation of PCM. This paper presents an improved measurement technique for the characterization of PCM using the T-history method. The suggested improvements include the arrangements made in three different prospects: the experimental setup, data processing and data representation. T-history measurements of organic RT21 and inorganic SP22 A17 (RUBITHERM® GmbH) PCM were performed. The applied arrangements resulted in the temperature accuracy of ±0.3 °C and the reduction of uncertainty associated with heat stored/released between the cooling and heating measurements. The obtained results showed some important aspects of the T-history PCM investigation and could provide more effective design and development process of the thermal energy storage systems based on the investigated materials

Immediate origin of the Moon as a post-impact satellite

The Moon is traditionally thought to have coalesced from the debris ejected by a giant impact onto the early Earth. However, such models struggle to explain the similar isotopic compositions of Earth and lunar rocks at the same time as the system’s angular momentum, and the details of potential impact scenarios are hotly debated. Above a high resolution threshold for simulations, we find that giant impacts can immediately place a satellite with similar mass and iron content to the Moon into orbit far outside Earth’s Roche limit. Even satellites that initially pass within the Roche limit can reliably and predictably survive, by being partially stripped and then torqued onto wider, stable orbits. Furthermore, the outer layers of these directly formed satellites are molten over cooler interiors and are composed of around 60% proto-Earth material. This could alleviate the tension between the Moon’s Earth-like isotopic composition and the different signature expected for the impactor. Immediate formation opens up new options for the Moon’s early orbit and evolution, including the possibility of a highly tilted orbit to explain the lunar inclination, and offers a simpler, single-stage scenario for the origin of the Moon

A bibliometric study of human–computer interaction research activity in the Nordic-Baltic Eight countries

Human–computer interaction (HCI) has become an important area for designers and developers worldwide, and research activities set in national cultural contexts addressing local challenges are often needed in industry and academia. This study explored HCI research in the Nordic-Baltic countries using bibliometric methods. The results show that the activity varies greatly across the region with activities dominated by Finland, Sweden, and Denmark, even when adjusting for differences in population size and GDP. Research output variations were larger for the top-tier conferences compared to entry-tier conferences and journals. Locally hosted conferences were associated with local increases in research activity. HCI research longevity appears to be an indicator of research maturity and quantity. HCI researchers typically collaborated either with colleagues within the same institution or with researchers from countries outside the Nordic-Baltic region such as US and the UK. There was less collaboration between national and Nordic-Baltic partners. Collaboration appeared especially prevalent for top-tier conference papers. Top-tier conference papers were also more frequently cited than regional-tier and entry-tier conferences, yet journal articles were cited the most. One implication of this study is that the HCI research activity gaps across the Nordic-Baltic countries should be narrowed by increasing the activity in countries with low research outputs. To achieve this, first-time authors could receive guidance through collaborations with experienced authors in the same institution or other labs around the world. More conferences could also be hosted locally. Furthermore, journals may be more effective than conferences if the goal is to accumulate citations.publishedVersio

Resource Re-allocation for Data Inter-dependent Continuous Tasks in Grids

Many researchers focus on resource intensive tasks which have to be run continuously over long periods. A Grid may offer resources for these tasks, but they are contested by multiple client agents. Hence, a Grid might be unwilling to allocate its resources for long terms, leading to tasks’ interruptions. This issue becomes more substantial when tasks are data inter-dependent, where one interrupted task may cause an interruption of a bundle of other tasks. In this paper, we discuss a new resource re-allocation strategy for a client, in which resources are re-allocated between the client tasks in order to avoid prolonged interruptions. Those re-allocations are decided by a client agent, but they should be agreed with a Grid and can be performed only by a Grid. Our strategy has been tested within different Grid environments and noticeably improves client utilities in almost all cases