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In this white paper, we introduce and discuss the personal television channel concept, a new content management and usage concept for personal video recorders. In addition, we concisely describe a possibility to implement targeted advertising, based on the personalization achieved by the personal channel concept.

This technical note is based on Bram Braat's master's thesis, written as a Industrial Design student at the Eindhoven University of Technology. The project was conducted at the User Experiences group in the context of the Hospitality project. The goal of this student project was to design a product or system that creates social interaction between people in a (semi-)public place. In this case to let tourists exchange experiences with each other in a hotel lobby. Tourist carry a lot of touristic experiences, for example information about nice restaurants, bars, best visiting times of museums, current events, unknown sights etc. Currently there is not much exchangeof this information while advice of other tourists appeared to be given more value than information by guiders or the tourist information. Based on this, a literature review towards social interaction in public places and an analysis of the context several concepts were created for systems that would enable social interaction between tourists. Throughout an iterative process these concepts were evaluated and developed using scenarios and experiential prototypes. This iterative process had a high user involvement with several user evaluations. This resulted in a final concept called the CityTIP system, where TIP stands for: 'Tourist Inspiring Pictures'. This system enables tourists to share their touristic photos with other guests as well gives them inspiration for exploring the city. The CityTIP system has been evaluated in a lab test to investigate thesocial interaction and general acceptance of the system. Based on these results a setup for further research is proposed, a setup for a more extensive lab test and a setup for a field test in ahotel lobby of a real hotel.

The advancement of current technology allows developing lightweightunobtrusive devices, which detect human physical activity. However, there has always been a major issue, hindering the regular usage ofthese gadgets - many people find it difficult to fit them in theirdaily routine. In this thesis, we develop an application, which allows us to measure the influence of online social networks on people involved in physical activity programs. On the grounds of our literature research, we identify different motivational triggers that can be employed for the design of a social network application in the context of physical activity programs. Based on these findings, we design and implement the ActiveTeam application, using Facebook as underlying social network service. In the course of the document we propose several methods to evaluate the behaviour of ActiveTeam users. These methods areintended to help us analyze and improve the application once it ismade available to a large number of users.

Brain-Computer Interfaces (BCIs) enable people to control appliances without involving the normal output pathways of peripheral nervesand muscles. A particularly promising type of BCI is based on the Steady-State Visual Evoked Potential (SSVEP). Users can selectcommands by focusing their attention on repetitive visual stimuli(RVSi) that change one of their properties (e.g. color or pattern) with a certain frequency. These properties as well as the devicethe RVSi are rendered on, can greatly affect the performance, applicability, comfort and safety of the BCI. Despite this fact, stimulation properties have received fairly little attention in the BCI literature to this date. Furthermore, a heavy emphasis is placedon BCI performance to the detriment of other important factors suchas comfort and safety. The research reported in this document aimsat studying the effects of stimulation properties on performance aswell as comfort of SSVEP-based BCIs. Research was performed in bothoffline and online settings, using a custom made high-performance BCI. Comfort was measured using a custom questionnaire. A largevariability across subjects was found, but the results confirm that stimulation properties have a considerable impact on performance and comfort of SSVEP based BCIs. In general, a large difference between stimulation states is beneficial for BCI performance, but detrimen-tal to user comfort. A couple of configurations were found that provide a good compromise between comfort and performance.

In this study we report on initial efforts to discover putative biomarkers for differential diagnosis of a systemic inflammatory response syndrome (SIRS) vs. sepsis; and different stages of sepsis. In addition, we also investigated whether there are proteins that can discriminate between patients who survived sepsis from those who did not. Our study group consisted of 16 patients, of which 6 died and 10 survived. We daily measured 28 plasma proteins, for the whole stay of the patients in the ICU. We observed that metalloproteinases and sE-selectin play a role in the distinction between SIRS and sepsis, and that IL-1a, IP-10 and sTNF-R2 and sFAS appear to be indicative for the progression from sepsis to septic shock. A combined measurement of MMP-3, -10, IL-1a, IP-10, sIL-2R, sFas, sTNF-R1, sRAGE, GM-CSF,IL-1ß, and Eotaxin allows for a good separation of patients that survived from those that died (mortality prediction with a sensitivity of 79% and specificity of 86%). Correlation analysis suggests a novel interaction between IL-1a and IP-10. The marker panel is ready tobe verified in a validation study with or without therapeutic intervention.

We present the design of an algorithm for use in an interactivemusic system that automatically generates music playlists that fit the music preferences of a user. To this end, we introduce a formal model, define the problem of automatic playlist generation (APG), and proof its NP-hardness. We use a local search (LS)procedure employing a heuristic improvement to standard simulated annealing (SA) to solve the APG problem. In order to employ this LS procedure, we introduce an optimization variant of the APG problem, which includes the definition of penalty functions and a neighborhood structure. To improve upon the performance of the standard SA algorithm, we incorporated three heuristics referred to as song domain reduction, partial constraint voting, an da two-level neighborhood structure. We evaluate the developed algorithm by comparing it to a previously developed approach based on constraint satisfaction (CS),both in terms of run time performance and quality of the solutions. For the latter we not only considered the penalty of the resulting solutions, but we also performed a conclusive user evaluation to assess the subjective quality of the playlists generated by both algorithms. In all tests, the LS algorithm was shown to be a dramatic improvement over the CS algorithm.

Video processing in software is often characterized by highly fluctuating, content-dependent processing times, and a limited tolerance for deadline misses. We present an approach that allows close-to-average-case resource allocation to a single video processing task, based on asynchronous, scalable processing, and QoS adaptation. The QoS adaptation balances different QoS parameters that can be tuned by user-perception experiments: picture quality, deadline misses, and quality changes. We model the balancing problem as a discrete stochastic decision problem, and propose two closely related solution strategies, for which the processing-time statistics are determined off line and at run time, respectively. We enhance both strategies with a compensation for structural (non-stochastic) load fluctuations. Finally, we validate our approach by means of simulation experiments, and conclude that both enhanced strategies perform close to the theoretical optimum.

Study of light-based skin rejuvenation needs prospective insights of mechanism of laser tissue interaction. A well-built model plays a key role in predicting temperature distribution in human skin exposed to laser irradiation. Therefore, it not only provides guidance for in vitro experiment, but also facilitates parametric studies of clinical treatment. In this project, three tasks were completed: Firstly, a new time-dependent mathematical model is built up to study dynamic thermal responses of human skin to laser irradiation. This model is a combination of three parts: MC (Monte Carlo) Simulation, which provides photon distribution; MATLAB data processing, which calculates heat generation rate from MC output; COMSOL modeling, compute real-time temperature change. Secondly, an experimental setup as built with 976nm laser diode of 1Watt and 4mm beam diameter. Based on the guidance of simulations, the system is designed to be in the best configuration, both for the requirement of experiment and for transportation. Thirdly, the mathematical model was validated by performing experiments with the experimental setup and ex vivo human skin. Two temperature measurement techniques were applied: thermocouple measurement and thermal camera measurement. Results derived from both experiment and simulations are compared. According to analysis, we may draw the conclusion that the model can serve as a reliable tool for predicting temperature distribution of human skin sample under laser irradiation, and it will facilitate parametric study of laser in skin rejuvenation. In addition, the innovative structure of the present model offers great probability to be further improved, by adjusting input parameters, boundary conditions, as well as functionality of the model. We believe that a further revised model, in the future, will be an even more powerful tool for improved treatments of skin rejuvenation.

Many photovoltaic cells and OLEDs are covered by cover glass or foil to protect the device against oxygen and moisture. The cover glassor foil is semitransparent for infrared radiation and conducts the heat and blurs lock-in thermograms. In lock-in thermograms of OLEDs with cover glass short circuits raise typically 10 mK in temperature,where as literature and observations suggest that polymers decompose into gas at way higher temperature behind the glass. A good interpretation of lock-in thermograms may be done by the understanding of the heat conduction and radiation through cover glass. Modelling of heat conduction and radiation around a short circuit in cover glass will be presented as well as first validation experiments where a short circuit has been imitated by a laser.

This report describes the theoretical background and development of an application to share physical activity information, as well as the results of a four-week field study in which people shared physical activity information as measured by the Philips Activity Monitor. The existing web-service DirectLife was enhanced with an interface that visualizes similarities, activity levels and patterns between users. The application, developed by deploying user-centered design methods, displays several attributes of physical activity. During the field study two groups of seven participants carried the activity monitor and shared activity information; either visualized on a publicly shared or private display. Visualizing similarities in physical activity is expected to increase interpersonal awareness, communication and perceived closeness. From the perspective of self-determination theory (SDT), this should increase the fulfillment of the need to belong. Such a fulfillment is expected to increase intrinsic motivation for physical activity and engagement in using the activity monitor. The results show the promise of using similarity and enhancing connectedness for technology-based persuasion. In addition, several recommendations are made for future efforts aimed at increasing motivation for physical activity.

A well designed mathematical model could serve as a direct, economical and flexible assistant tool to enable in-depth understanding of thermal response of human skin under laser irradiation. It provides us with reliable predictions of temperature change in skin tissue under laser irradiation. The mathematical model in this project is made up of three stages: Monte Carlo simulation, MATLAB data processing and COMSOL modeling. Based on the model, two topics of research were carried out as a preparation step for actual experiment. First, the temperature distribtion difference when applying different settings of source type for the laser: SourceType = 5 (Top-hat); SourceType =6 (Gaussian) and SourceType = 8 (Fiber) was assessed. Second, thetemperature distribution when using different value of µs corresponding to different initial temperatures T0 compared with using a constant µs value equal to the value of µs at 20º C was also tested.

A fully autonomous inductive boost converter for indoor photovoltaic harvesting with maximum power point tracking circuit is implemented in a commercial 0.25um CMOS process. The converter can handle input power from 5uW up to 10mW and charge a battery or a super-capacitor up to 5V. Its control circuit consumes between 0.8uA and 2.1uA depending on the input power level, resulting in a peak end-to-end efficiency of 70% when tracking a maximum input power of 17uW.

The just noticeable difference (JND) in black level (BL), whitelevel (WL), and chroma as visible in natural images under practical viewing conditions is determined. The potential effect of cultural background on the JNDs is evaluated conducting the same experiment in China and in the Netherlands. In general, there is a big difference in JND depending on the content of the natural image, as we expected. Only for some images,we found a difference in JND between China and the Netherlands. It seems that for these images people on average were looking to a different area in the image during their assessment

Brain-computer interfaces (BCI) based on Steady State Visual Evoked Potential (SSVEP) can provide higher information transfer rate and require shorter calibration than BCIs based on other modalities. For safety and comfort, the frequency of the repetitive visual stimuli seliciting the SSVEP should be higher than 30 Hz. However, in such frequency range, only a limited number of frequencies can elicit sufficiently strong SSVEPs for BCI purposes. Thus, the conventional approach, consisting in presenting various repetitive visual stimuli at different frequencies, is not feasible for high frequencies. Indeed this would bring low communication bitrates. To increase the number of possible repetitive visual stimuli, we consider modulating the phase of the stimulus instead of the frequency. In this paper, we present an approach to reliably detect the stimulus phase from the recorded SSVEP.

The document consists of a diploma thesis, which describes a completely automated segmentation chain for the bones of the human hip joint from diagnostic MR images including the model-building process for the corresponding anatomical structures. Mainly relying on the well-established model-based segmentation framework, the approach discusses strategies such as the Hough Transform for pre-positioning the involved surface models in the image to enhance robustness of the model-based framework. Furthermore, simple strategies for optimal choice of parameters for the model-based framework are investigated. Theproposed methods have been tested on a set of nine MR images of female patients, all suffering from hip dysplasia.

In this report, we present a method using the capillary structuresunder the "distal interphalangeal joint" (DIP joint), which is located between the second and third (distal) phalanges of the finger, for achieving secure biometric authentication. Images of the DIPjoint are acquired using a microscope and they are subsequently processed to enhance the visibility of the blood vessels. DIP joint images cannot be easily faked and are not left behind. During enrollment, a set of images of the DIP joint are recorded and a region of interest that contains a large concentration of blood vessels is selected to serve as template for the enrolled subject. During authentication, the acquired image is compared to the template of the claimed identity by means of a score derived from the 2D cross-correlation. We have recorded a database containing images of sixty fingers (from nineteen subjects) on which our experiments resulted in an optimal equal-errorrate (EER) of 0%.

Background and purpose: It is the purpose of this article to review, which are possible criteria that rehabilitation technology should meet in order to offer upper limb training after stroke that is based on principles of motor learning. Methods: A computerised literature search was conducted in PubMed, MEDLINE, CINAHL, and EMBASE. The period of time searched was 1997-2007. 130 journal papers (or booksections) were selected and have been used to write this review. Results: State-of-the art approaches in motor learning and training for stroke patients are described, followed by an overview of technology that supports training of arm and hand function after stroke. A list of possible criteria for upper limb rehabilitation technologyis presented. Finally, this paper evaluates strengths and weaknesses of current technological systems on the basis of the criteria thatare proposed. The review concludes with a vision on future developments.

This report describes basic technology developed for higher-level photo management applications. Based on the visual comparison of photos, distance measures are defined to yield a numerical value indicating how similar (or dissimilar) photos or groups of photos are. This enables a series of mid-level applications such as photo clustering, ordering or search by example; based on these, higher-level applications have been built, exploiting the basic functionality offered by this technology. The metrics defined in this report have been tested on large amounts of content. Real-world test sets comprising thousands of photos have been used, and, for video content-analysis applications, this technology served as basis for the analysis of dozens, if not hundreds of content from different genres, such as news or sports content.

Philips has designed an optical mammography machine. In this machine the breast is suspended into a cup in which the measurements take place. A special fluid is inserted into the cup to prevent the light from going around the breast instead of going through it but this fluid also weakens the signal. Therefore the cup's shape should be close to the breast's shape. The aim of this project was to design a device to measure the breast's shape. This device was used to perform a pilot study among 18 women, 36 breasts in total. There are several possibilities to create 3D images for example MRI, interfero-metry and triangulation. The method of triangulation is chosen to build a set-up. This set-up contains a video projector to project images into a tank filled with water. Two camera's capture these images. Special software has been written in LabVIEW to create 3D images out of these data. The maximum height of the breast and the FWHM was measured for all breasts. A correlation was found between bra cup size and the maximum height of the breast. On average the breast was 64 mm high, with a standard deviation of 8.5 mm. No correlation was found between the FWHM and a form of bra size or chest circumference. The average FWHM is 7.6 cm with a standard deviation of 2.5 cm.

Wireless power transfer by magnetic induction offers a simple to use way to recharge mobile devices like e.g. mobile phone, music players or medical sensors. As shown by a previous report and an existing Power Pad demonstrator, wireless inductive power transfer is possible with a good power efficiency and low magnetic radiation only on a surface and with local activation underneath the mobile device. However, compared to the existing Power Pad, an improved detection method for the local activation is needed. This report investigates the use of RF-ID tags for the position detection. It addresses the problem to multiplex the RF-ID signal to a number of neighboured powercells to locate the device and the simultaneous transfer of power and information. To investigate the solution, a demonstrator is designed and built. This first circuit can activate 4 neighboured and overlapping cells. The circuit consists of a NFC/RF-ID PN511 con-troller by NXP, an analogue multiplexer to direct the RF-ID signal to the cells and FETs as switches to switch the power signal to each cell. The system operates at 500 kHz for the power transmission and at 13.56 MHz for the RFID data transmission. The circuit is controlled by an external computer using a dedicated software developed with LabView.