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Following the ever-improving performance of data converters, the accuracy of the clock that is sampling the converter, needs to improveat the same pace. The clock accuracy is especially a problem for high-resolution, wide bandwidth converters.The aim of this project isto provide for a next-generation high-performance clock as a libraryblock for the Process & Library Technology Group of CTO (formerlyAMoS). This clock should provide a maximum output frequency of atleast 2GHz with only a few ps of jitter while operating in a mixed-signal environment. Since the design is intended as a library block,boundary condi-tions are flexibility (for example tunability of theoutput frequency), robust-ness (for example to interference, varia-tions in PVT, etc.) and portability to new technologies. In the exi-sting PLL, the current-controlled oscillator (CCO) was identified asthe major opportunity for lowering the interval jitter of the PLL(i.e. the 1/f2 part of the phase noise of the output clock). Hence,this TN analyzes the use of an alterative oscillator based on an LC-tank. This LC-oscillator is based on an existing design by Nenad Pavlovic. It is designed in a 90-nm CMOS technology. The analysis leadsto the following conclusions: the LC- oscillator is tunable from 4.9GHz to 6.6GHz. The high initial output frequency enables a sufficienttuning range at lower frequencies after division.Easy division ratiosenable synthesizing any frequency below 1.68GHz. The phase noise ofthe LC-oscillator is characterized by the number L=-189dBc/Hz. Assu-ming a PLL bandwidth of 1MHz, the LC-oscillator would contribute only0.1ps of interval jitter.This is about 60 times less than that of theringoscillator. Part of the improvement is due to a 10 times largerbias current; i.e. 2mA. The major part of the improvement is due tothe quality factor of the LC-resonator.The non-linear varactor chara-cteristic causes up-conversion of noise and interference. Hence, theperformance of the LC-oscillator is ultimately limited by the varactorquality. The tail current of the oscillator determines the oscillatorswing The oscillator swing,in its turn,“averages” the varactor value.As a consequence, the oscillator frequency can be tuned by varying the tail current. This tuning mechnanism allows for a straightforwardintegration of the LC-oscillator in the existing PLL architecture.The effect of supply noise and other interference is largest whenthey couple into the tune pin of the varactors. Since the oscillatoris referenced to ground, these pins as well need to be decoupled toground in order to keep the interference as a common-mode signal.For the same reason, the inverters that set the bank of digital capacitors need to be connected to the analog supplies as well.

After a description of the structure and function of human skin, including the underlying fat layer, both in vitro and in vivo studies on the mechanical properties of separate skin layers are discussed: e.g. those of stratum corneum, living epidermis and the subcutaneous fat layer. Since the properties of the dermis are already widely known, this skin layer is left out of consideration. In addition, models on the mechanical behavior of human skin are considered.

This report describes the work done during a six months internshipat Philips Research for a Masters in Electronic and Electrical Engineering. An existing table-top tomography system for measuring lightin phantom breasts was restored. Updated software control and image reconstruction software was created using LabVIEW. Furthermore, wehave realised a new system and software to carry out spectroscopic measurements of diffuse reflectance light in turbid media.The set upcomprises a broadband light source, a spectrometer and a probe. The design for the probe allows for many different source and detector arrangements to be investigated. The software allows detector fibres selected by a user to be measured sequentially by producing controlsfor a fibre switch. The set-up can measure both fluids and solidsand can successfully accommodate for high dynamic range in measurements by altering the integration times through an algorithm implemented in the software. We have done measurements on forearms and first results using the set-up indicates the possibility of measuring Hb and HbO2.

Many views on the experience economy start with the behavior of actors in society at large and try to understand and explain their dynamics. In other words, the focus is on the external, objective, physical world of experience. But since experiences are inherently personal and only exist in our own internal, subjective, mental universe it is interesting to start from the inside and see what cognitive science can tell us about the central role of experience and story. This article is therefore quite literally an inside story about the experience economy and the pervasiveness of story and text.

For many speech telecommunication technologies a robust speech activity detector is important. An audio-only speech detector will givefalse positives when the interfering signal is speech or has speech characteristics. The modality video is suitable to solve this problem. In this report the approach to and implementation of a decision-based audiovisual speech detector is given. Acoustic and visual features of speech are first separately investigated. Firstly, a common method for speech detection based on audio has been built. Secondly, from the video data the mouth features have been extracted with the implementation of an own idea. The visual features were used to create a conservative visual non-speech detector. The low false detection rate makes the visual non-speech detector suitable to rule out some false speech detections of an audio only solution. Finally, the combinationof the audio detector and the video detector leads to an audiovisualspeech detector which uses basic mouth features and a common acousti-cal speech detection method to outperform an audio-only solution.

The market of LEDs increases exponentially over the years as well as their power. However, at the same time the mean time to failure should remain superior to 100,000 hours. The major difficulty comes from the mechanical stress in the LED structure, which is roughly proportional to the inverse of the thermal conductivity. Consequently, it is really important to determine thermal conductivity of the materials used in LEDs. In the same way, the thermal conductivity of films is lower than the thermal conductivity of the bulk material. Unfortunately, thermal conductivity measurement is difficult on two-dimensional structures. Then an appropriate method had to be developed. The 3 omega thermal conductivity measurement method has been used extensively to measure the thermal properties of bulk and thin film dielectric materials. Tests on different materials will allow to find materials with a higher thermal conductivity. The thermal conductivity measurement will be elaborated by two different methods defined the isotropic and anisotropic properties, the "slope method" and the 2D heat conduction.

In this project integrated antennas on a LAMP3 substrate for automotive radar systems at 24 GHz and wireless networks at 60 GHz have been designed. The most severe requirements on the antennas were the large bandwidth, which can not be met with conventional patch antennas. A tapered slot antenna and a bow-tie slot antenna both for 24 GHz as well as a scaled version of the bow-tie slot antenna designed for 60 GHz were fabricated. The return loss bandwidth as well as the radiation patterns of the fabricated antennas were measured. 60 GHz small-scale indoor radio channel measurements have been performed. An omni directional antenna, a fan beam antenna and a bow-tie slot antenna have been used as receive antennas and a omni directional antenna was used as transmit antenna.

We address the problem of discovering fuzzy subsumption relations between concepts from different concept hierarchies. We investigate two approximate reasoning schemes which aim at improving of the fuzzysubsumption relation assessment. The first scheme utilizes the structure of a concept hierarchy and the second takes advantage of a Google-based dissimilarity measure. We present the results of experiments with several music concept hierarchies from actual sites on the Internet.

In vivo transmission profiles of the index finger were assessed using cw-spectroscopy. The capability to noninvasively monitor changes in blood perfusion was measured on three volunteers. The results suggest to use the analysis of absorption spectra for the recognition of high-perfused joints. This could help to detect a inflammation of the joint, e.g. due to a rheumatoid disease. In total, thirteen measurements on seven different volunteers were performed. Models are proposed from which a change in the oxygenation can be understood.

Beam shaping is currently being considered for various lighting applications. One of the applications which is currently being investigated is related to video flash where the width of the light from flash is coupled to the zoom function of the camera. This means that for an object to be filmed at a distance of 7m beam width of 2*10º issufficient while at a distance of 2 m the beam width needs to be more than 2*30º and sufficiently homogeneous. Here we describe various strategies for replicated structures which can be combined with liquid crystals for switching various states to change the beam width.

This White Paper has been prepared as a result of a symposium and of existing Philips research activities in the diverse and complex area of neurotherapy. For the symposium, key note speakers specializing in the main neurotherapy areas of brain stimulation, pain management and neuro-rehabilitation were invited to speak and provide insight on their subjects. Their talks and workshops would subsequently highlight areas of treatment and diagnoses that could be identified aspotential research subjects in the area of neurotherapy.

Software reuse is considered one of the main techniques to increasesoftware productivity. We present two simple mathematical argumentsthat show some theoretical limits of reuse. It turns out that the increase of productivity due to internal reuse is at most linear, farfrom the needed exponential growth. Even worse, the linear increasecan only be sustained during the first several years of applying internal reuse (later it saturates to a constant). With external reuseone can achieve exponential increase of productivity, at least in theory. Unfortunately, the price paid for the exponential growth is diminishing innovation. In fact, the innovation ratio due to externalreuse diminishes exponentially fast to zero.

This thesis focuses on the issue of mapping 3D-TV rendering applications to a multiprocessor platform. The target platform aims to address tomorrow's multi-media consumer market. The prototype chip, called Wasabi, contains a set of TriMedia processors that communicate viaa shared memory, fast message passing channels that support multi-chip system and some application-specific co-processors. In the targeted market, it is important to verify that a system under design iscorrectly dimensioned. But during architecture research the applications for which the system is being designed are often not yet available. By mapping 3D-TV rendering applications to Wasabi, the performance figures are obtained not only to check the mapping feasibilitybut also to match the application requirements with the hardware architecture. In this thesis, two rendering algorithms are dealt withby following approach. First, sequential C code is developed. Thereafter, the code is optimized and vectorized using the special, SIMD-like media instructions supported by the TriMedia. Finally, multithreaded programs are developed and simulated on a cycle-accurate simulator of the Wasabi architecture to obtain the performance figures.

Travel Report to the 2005 IEEE International Symposium on Circuits and Systems.

This report contains the results of a feasibility study of applyingLinux facilities for isolating and protecting processes, and for communication and synchronisation between processes, to the MG-R architecture so as to improve the robustness. Moreover some guidelines andtrade-offs are discussed how to define process boundaries within the MG-R architecture. These guidelines are illustrated with examples.Moreover a demonstrator application is presented. The report describes how the Koala toolset could be extended to support processes, both at specification level and at implementation level.

Actuation principles of superparamagnetic beads applicable on biosensing (at single beads and chain orderning) are studied in this report. This research can be used to develop new techniques that are able to accelerate bio-assays. An experimental setup containing a sub-microliter fluid volume surrounded by four miniaturized electromagnets is designed and fabricated. On the basis of velocity measurements, the induced bead behaviour has been compared to theoretical models.

ABSTRACT: The power of LEDs increases exponentially over the years,while the mean time to failure (MTTF) should remain >100000 hours. The reliability requirement limits the junction temperature and the thermo elastic stresses, which are roughly inversely proportional tothe thermal conductivity of the heat spreaders. The 3omega method has been set up to measure dynamically the thermal conductivity of anisotropic thin layers preferably in situ. CONCLUSIONS: The 3omega method measurement set up is operational from 10 Hz to 10 kHz The measured thermal conductivity of silicium deviates 50%, so the set upneeds to be improved. The length of the heater has already been checked. The goodness of fit of the sensor/heater calibration R² = 0.99998 The goodness of fit of the 3omega slope method R² = 0.99