What is meant with print quality, what makes people perceive the quality of an image in a certain way? An inquiry was made about what the parameters are that strongly affect the perception of digital printed images. A subjective test and some measurements make the basis for the thesis. The goal was to find a tool to predict perceived image quality when investigating the connections between the subjective test and the measurements. Some suitable images were chosen, with a variety of motifs. A test panel consisting of people that are used to observe image quality answered questions about the perception of the quality. Measurements were made on a special test form to get information about the six different printers used in the investigation. One of the discoveries was made when two images with the same colorful motif were compared. The first image got a much higher grade for general quality than the second image, even though the second image was printed with a printer that had a larger color gamut. The reason of this is that the first image consists of more saturated colors, and the second image has more details. The human eye perceives the more saturated image to be better than the image with more details. Another discovery was the correlation between the perceived general quality of a colored image and the perceived color gamut. One conclusion was that a great difference between two calculated color gamuts resulted in a large difference in perception of the color gamuts. A discovery of an image with very few colors and many glossy surfaces was that print mottle and sharpness are strictly connected to the general quality.

Multithreading is a processor technique that can effectively hide long latencies that can occur due to memory accesses, coprocessor operations and similar. While this looks promising, there is an additional hardware cost that will vary with for example the number of contexts to switch to and what technique is used for it and this might limit the possible gain of multithreading. Network processors are, traditionally, multiprocessor systems that share a lot of common resources, such as memories and coprocessors, so the potential gain of multithreading could be high for these applications. On the other hand, the increased hardware required will be relatively high since the rest of the processor is fairly small. Instead of having a multithreaded processor, higher performance gains could be achieved by using more processors instead. As a solution, a simulator was built where a system can effectively be modelled and where the simulation results can give hints of the optimal solution for a system in the early design phase of a network processor system. A theoretical background to multithreading, network processors and more is also provided in the thesis.

In the newspaper printing industry, offset is the dominating printing method and the use of multicolour printing has increased rapidly in newspapers during the last decade. The offset printing process relies on the assumption that an uniform film of ink of right thickness is transferred onto the printing areas. The quality of reproduction of colour images in offset printing is dependent on a number of parameters in a chain of steps and in the end it is the amount and the distribution of ink deposited on the substrate that create the sensation and thus the perceived colours. We identify three control points in the offset printing process and present methods for assessing the printing process quality in two of these points: • Methods for determining if the printing plates carry the correct image • Methods for determining the amount of ink deposited onto the newsprint A new concept of colour impression is introduced as a measure of the amount of ink deposited on the newsprint. Two factors contribute to values of the colour impression, the halftone dot-size and ink density. Colour impression values are determined on gray-bars using a CCD-camera based system. Colour impression values can also be determined in an area containing an arbitrary combination of cyan magenta and yellow inks. The correct amount of ink is known either from a reference print or from prepress information. Thus, the deviation of the amount of ink can be determined that can be used as control value by a press operator or as input to a control system. How a closed loop controller can be designed based on the colour impression values is also shown. It is demonstrated that the methods developed can be used for off-line print quality monitoring and ink feed control, or preferably in an online system in a newspaper printing press. / <p>Report code: LiU-TEK-LIC-2005:02.</p>

<p>The need for increased safety and efficiency in civil aviation is pushing the introduction of Automatic Dependent Surveillance - Broadcast (ADS-B). The basic principle of ADS-B is that each aircraft is able to communicate its position and status over a radio data link to surrounding aircraft. In this way each aircraft obtains a detailed picture of the surrounding traffic. During a period of transition from today's radar surveillance to ADS-B many aircraft will not be equipped with the new data link technology and will therefore be invisible to the ADS-B equipped aircraft. The Traffic Information Service - Broadcast (TIS-B) has been conceived to be the solution to this problem. TIS-B is defined as a broadcast surveillance service in which data from the ordinary ground radar system is transmitted from a ground station to airborne systems, providing an air situation picture of the non-ADS-B stations. </p><p>The topics of this thesis are the definition and implementation of a TIS-B server. The presented solution is an evaluation TIS-B server that will receive data from a data-fusing tracker and provide one or several TIS-B ground stations with data filtered according to the settings of the server.</p>

<p>In the future network-based Swedish Defence (NBD), attaining information superiority will be of great importance. This will be achieved by a network of networks where decision-makers, information- and weapon-systems are linked together. As a part of the development of NBD, we have performed a study of user interface design for a future network-based tool package for analysis of sensor systems, referred to as the C2SR-system. </p><p>This thesis was performed at Ericsson Microwave Systems AB, Sensor and Information Networks, during the autumn 2002. A pre-study concerning the requirements of usability, trustworthiness and functionality of a user interface for the C2SR-system was performed. Officers representing the future users in the NBD played an important role when gathering these requirements. Another important part of the pre-study was the evaluation of software that contains parts of the functionality necessary for the C2SR-system. </p><p>On the basis of the results from the pre-study, we have designed a user interface to the future C2SR-system. To demonstrate the most important conclusions, a prototype was implemented.</p>

<p>When searching for better and more practical interfaces between users and their computers, additional or alternative modes of communication between the two parties would be of great use. This thesis handles the possibilities of using eye and head movements as well as voice input as these alternative modes of communication. </p><p>One part of this project is devoted to find possible interaction techniques when navigating in a computer interface with movements of the eye or the head. The result of this part is four different controls of an interface, adapted to suit this kind of navigation, combined together in a demo application. </p><p>Another part of the project is devoted to the development of an application, with voice control as primary input method. The application developed is a simplified version of the application ActiViewer., developed by AerotechTelub Information&Media AB.</p>

<p>Real-time sound synthesis in computer games using physical modeling is an area with great potential. To date, most sounds are pre-recorded to match a certain event. Instead by using a model to describe the sound producing event, a number of problems encountered when using pre-recorded sounds can be avoided. This thesis will introduce these problems and present a solution. The thesis will also evaluate one such physical model, for rain sound, and implement a real- time simulation to demonstrate the advantages of the method.</p>

<p>This report is a part of a diploma work, conducted as a part of a Master of Science degree. The diploma work consists of a preliminary study, two case studies, a user study, a paper and this report. It was created at the Linköping University for the department of Science and Technology, in cooperation with Unilever Research in the UK, and partly with the EC founded project, Smartdoc IST-2000-28137. </p><p>Hand-held, mobile devices like Personal Digital Assistances (PDAs) are becoming increasingly popular in today’s wireless world. While trying to pack all the possible information into a small window, a nightmarish scenario is created for the interface designer to deal with. The goal for this project was to investigate different Visual User Interfaces (VUIs)on PDAs, and how to apply desktop interaction techniques to PDAs. </p><p>A VUI model based on Zooming User Interface (ZUI) techniques, to adapt two complete different visualisation application areas; on-line brand-based shopping and flood warning system for PDAs, is presented. The on-line brand- based shopping was evaluated in a benchmark usability study comparing it to traditional PC based on-line shopping.</p>

<p>New Virtual Reality technologies provide the possibility of widening access to information in data. Haptics, the technology of touch, could be an interesting future aid and have large impact on medical applications. The use of haptic devices allows computer users to use their sense of touch, in order to feel virtual objects with a high degree of realism. </p><p>The aim of the thesis is to investigate the potential deployment and the benefits of using haptic force feedback instruments in maxillo-facial surgery. Based on a produced test application, the thesis includes suggested recommendations for future haptic implementations. </p><p>At the Department of Maxillo-Facial Surgery, at the Karolinska Hospital in Stockholm, Virtual Reality technologies are used as an aid to a limited extent during the production of physical medical models. The physical medical models are produced with Rapid Prototyping techniques. This process is examined and described in the thesis. Moreover, the future of the physical medical models is outlined, and a future alternative visualizing patient data in 3D and use haptics as an interaction tool, is described. Furthermore, we have examined the present use of haptic technology in medicine, and the benefits of using the technology as an aid for diagnostic and treatment planning. </p><p>Based on a presented literature study and an international outlook, we found that haptics could improve the management of medical models. The technology could be an aid, both for physical models as well as for virtual models. We found three different ways of implementing haptics in maxillo-facial surgery. A haptic system could be developed in order to only manage virtual medical models and be an alternative solution to the complete Rapid Prototyping process. A haptic system could serve as a software, handling the image processing and interfacing from a medical scanner to an Rapid Prototyping system. A haptic system could be developed as an alternative interaction tool, which could be implemented as an additional function in currently used image processing software, in order to improve the management of virtual medical models before the Rapid Prototyping process. </p><p>An implementation for planning and examination in maxillo-facial surgery, using haptic force feedback interaction, is developed and evaluated. The test implementation is underlying our aim of investigating the potential deployment and the benefits of using haptic force feedback instruments in maxillo-facial surgery. </p><p>After discussing the possible future of our implementation and the future of haptic force feedback in maxillo-facial surgery, a recommendation is given as a conclusion of our total work.</p>

<p>In this Master's thesis, Maximum Likelihood-based parametric identification methods for discrete-time SISO Hammerstein models from perturbed observations on both input and output, are investigated. </p><p>Hammerstein models, consisting of a static nonlinear block followed by a dynamic linear one, are widely applied to modeling nonlinear dynamic systems, i.e., dynamic systems having nonlinearity at its input. </p><p>Two identification methods are proposed. The first one assumes a Hammerstein model where the input signal is noise-free and the output signal is perturbed with colored noise. The second assumes, however, white noises added to the input and output of the nonlinearity and to the output of the whole considered Hammerstein model. Both methods operate directly in the time domain and their properties are illustrated by a number of simulated examples. It should be observed that attention is focused on derivation, numerical calculation, and simulation corresponding to the first identification method mentioned above.</p>