Haptic cues as a utility to perceive and recognise geometry

Research has been conducted on how to aid blind peoples’ perceptions and cognition of scientific data and, specifically, on how to strengthen their background in mathematics as a means of accomplishing this goal. In search of alternate modes to vision, researchers and practitioners have studied the opportunities of haptics alone and in combination with other modes, such as audio. What is already known, and has motivated research in this area, is that touch and vision might form a common brain representation that is shared between the visual and haptic modalities and through haptics learning is active rather than passive. In spite of extensive research on haptics in the areas of psychology and neuropsychology, recent advances and rare experiences in using haptic technology have not caused a transfer from basic knowledge in the area of haptics to learning applications and practical guidelines on how to develop such applications. Thus motivated, this study investigates different haptic effects, such as free space, magnetic effects and the bounded box when blind people are given the task of recognising and manipulating classes of 3D objects with which they have varying familiarity. In parallel, this study investigates the applicability of Sjöström’s guidelines on haptic applications development and uses his problem classification to capture knowledge from the experiments. The results of this study show that users can easily recognise and manipulate familiar objects, albeit with some assistance. There is an indication that users completed tasks faster and needed less assistance with magnetic effects. However, they were not as satisfied with this mode. While the results of this study show that haptics have the potential to allow students to conceptualise 3D objects, much more work is needed to exploit this technology to the fullest. Objects with higher complexity are difficult for students, and, in their opinion, the virtual objects (as presented) leave much room for improvement. Sjöström’s error taxonomy proved useful, and four of five sub-guidelines tested were confirmed to be useful in this study.     

Accessibility of audio and tactile interfaces for young blind people performing everyday tasks

Increasingly, computers are becoming tools of communication, information exploring and studying for young people, regardless of their abilities. Scientists have been building knowledge on how blind people can substitute hearing or touch for sight or how the combination of senses, i.e., multimodalities, can provide the user with an effective way of exploiting the power of computers. Evaluation of such multimodal user interfaces in the right context, i.e., appropriate users, tasks, tools and environment, is essential to give designers accurate feedback on blind users’ needs. This paper presents a study on how young blind people use computers for everyday tasks with the aids of assistive technologies, aiming to understand what hindrances they encounter when interacting with a computer using individual senses, and what supports them. A common assistive technology is a screen reader, producing output to a speech synthesizer or a Braille display. Those two modes are often used together, but the research studied how visually impaired students interact with computers using either form, i.e., a speech synthesizer or a Braille display. A usability test has been performed to assess blind grade-school students’ ability to carry out common tasks with the help of a computer, including solving mathematical problems, navigating the web, communicating with e-mail and using word processing. During the usability tests, students were allowed to use either auditory mode or tactile mode. Although blind users most commonly use a speech synthesizer (audio), the results indicate that this was not always the most suitable modality. While the effectiveness of the Braille display (tactile user interface) to accomplish certain tasks was similar to that of the audio user interface, the users’ satisfaction rate was higher. The contribution of this work lies in answering two research questions by analysing two modes of interaction (tactile and speech), while carrying out tasks of varying genre, i.e., web searching, collaboration through e-mail, word processing and mathematics. A second contribution of this work is the classification of observations into four categories: usability and accessibility, software fault, cognitive mechanism and learning method. Observations, practical recommendations and open research problems are then presented and discussed. This provides a framework for similar studies in the future. A third contribution of this work is the elaboration of practical recommendations for user interface designers and a research agenda for scientists.     

Effects of freezing/thawing on the microstructure and the texture of smoked Atlantic salmon (Salmo salar)

The changes in microstructure and texture during smoking of fresh and frozen/thawed Atlantic salmon was studied in fish from three different origins; ocean-ranched Atlantic salmon (Salmo salar) from Iceland and two groups of farmed Atlantic salmon from northern and western Norway. The muscle fibers from the frozen and thawed fish shrank, and the extracellular space increased compared to the fresh muscle. The muscle fibers from salmon fillets with smaller fiber diameter shrank to a less extent than fibers from salmon material with a larger fiber diameter. After smoking the space between the fibers and the fiber shrinkage increased to a higher extent in the muscle from the salmon that were frozen prior to smoking than muscle smoked from fresh salmon. The initial cross-sectional area of the fibers was not found to be related to the yield during smoking.     

Textural Properties of Raw Salmon Fillets as Related to Sampling Method

Textural properties of raw Atlantic salmon (Salmo salar) fillets from different origin were studied on different locations of the fillets. Three instrumental methods were applied for evaluation of textural properties. Two methods were based on puncture tests, using flat-ended cylinder or spherical probes measuring the hardness of the fillet. The third method was based on cutting the fillet with a blade and measuring the shear force. Hardness and shear force increased from head to tail, and the location below the dorsal fin was found to be most reliable. The shear force method was found to be more sensitive than the puncture methods and best suited for practical application.     

Effects of different salting and smoking processes on the microstructure, the texture and yield of Atlantic salmon (Salmo salar) fillets

The effect of different conditions during the salting and smoking process on the microstructure and the texture of salmon fillets was studied in interaction with different raw salmon material; ocean-ranched Atlantic salmon (Salmo salar) from Iceland and two groups of farmed Atlantic salmon (Salmo salar) from Norway, one from Northern Norway and one from Western Norway. The ocean-ranched salmon was found to have significantly smaller fiber diameters and higher shear force compared to the farmed fish. The cross-sectional area of the muscle fibers decreased during the salting and smoking process. Small differences were noted in the cross-sectional area between smoked fillets processed by different salting and smoking methods. However, the cross-sectional area of fibers in dry salted fish fillets from the farmed groups were significantly smaller than in the brine salted fillets, as the fibers shrunk more during dry salting than brine salting. The force required to shear the smoked fillets was significantly higher than for the unprocessed fillets, but was not found to be related to the different salting and smoking processes. Yield during smoking was not related to the initial cross-sectional area or the shear force of the unprocessed muscle.