Direct measurement of the on-chip insertion loss of high finesse microring resonators in Si3N4-SiO2 technology.

Microring resonators show the possibility for designing Very Large Scale Integrated (VLSI) photonic circuits by cascading them. In order to realize the devices, the on-chip insertion loss becomes an important parameter. The direct measurement of the on-chip insertion loss of a high finesse microring resonator will be presented. Its value (0.1 ± 0.1) dB is low, in agreement with calculations

The factor of time in the life cycle assessment of housing

Conducting life cycle assessments, or LCAs, involves many uncertainties, including those related to the factor of time. Time is very important in the environmental assessment of housing, because of the relatively long service life of houses. During a house's service life many changes occur, which are not usually considered in today's LCAs. Nevertheless this is of major importance in order to be able to make complete and accurate environmental assessments of housing. The aim of this article is to identity and classity the aspects belonging to the factor of time and to select solutions to handle these aspects in LCAs. On the one hand a difference is made between a static and a dynamic approach. On the other hand construction, demolition and frequency are distinguished. Six aspects of the factor of time resulted: design, production technology, re-design, waste treatment technology, technical service life and functional service life. So far only static factors are taken into account in LCAs, and only partly. To involve all the static aspects as well as to include the dynamic aspects, relationships between the six aspects of the factor of time have been defined and the most suitable solutions are assigned to the different groups of aspects, including scenarios, sensitivity analyses, tuming points and potentials

Experimental and numerical study of SiON microresonators with air and polymer cladding

A systematic experimental and numerical study of the device performance of waveguide-coupled SiON microresonators with air and polymer cladding is presented. Values of device parameters like propagation losses of the microresonator modes, the off-resonance insertion losses, and the straight waveguide to microresonator coupling are determined by applying a detailed fitting procedure to the experimental results and compared to results of detailed numerical simulations. By comparing the propagation losses of the fundamental TE polarized microresonator mode obtained by fitting to the measured spectra to the also experimentally determined propagation losses in the adjacent straight waveguide and the materials losses, it is possible to identify the loss mechanisms in the microresonator. By comparing experimental results for microresonators with air and polymethylmethacrylate cladding and a detailed numerical study, the influence of the cladding index on the bend losses is evaluated. It is demonstrated that the presence of an upper cladding can, under the right conditions, actually be beneficial for loss reduction

Modelling Eco-Driving Support System for Microscopic Traffic Simulation

Microscopic traffic simulation is an ideal tool for investigating the network level impacts of eco-driving in different networks and traffic conditions, under varying penetration rates and driver compliance rates. The reliability of the traffic simulation results however rely on the accurate representation of the simulation of the driver support system and the response of the driver to the eco-driving advice, as well as on a realistic modelling and calibration of the driver’s behaviour. The state-of-the-art microscopic traffic simulation models however exclude detailed modelling of the driver response to eco-driver support systems. This paper fills in this research gap by presenting a framework for extending state-of-the-art traffic simulation models with sub models for drivers’ compliance to advice from an advisory eco-driving support systems. The developed simulation framework includes among others a model of driver’s compliance with the advice given by the system, a gear shifting model and a simplified model for estimating vehicles maximum possible acceleration. Data from field operational tests with a full advisory eco-driving system developed within the ecoDriver project was used to calibrate the developed compliance models. A set of verification simulations used to illustrate the effect of the combination of the ecoDriver system and drivers’ compliance to the advices are also presented

Direct Laser Ablation and Ionization of Solids for Chemical Analysis by Mass Spectrometry

A laser ablation/ionization mass spectrometer system is described for the direct chemical analysis of solids. An Nd:YAG laser is used for ablation and ionization of the sample in a quadrupole ion trap operated in an ion-storage (IS) mode that is coupled with a reflectron time-of-flight mass spectrometer (TOF-MS). Single pulse experiments have demonstrated simultaneous detection of up to 14 elements present in glasses in the ppm range. However, detection of the components has produced non-stoichiometric results due to difference in ionization potentials and fractionation effects. Time-of-flight secondary ionization mass spectrometry (TOF-SIMS) was used to spatially map elemental species on the surface and provide further evidence of fractionation effects. Resolution (m/Dm) of 1500 and detection limits of approximately 10 pg have been achieved with a single laser pulse. The system configuration and related operating principles for accurately measuring low concentrations of isotopes are described

Laser Ablation -Ion Storage Time of Flight Mass Spectrometry

Abstract A new mass spectrometer system was developed for studying laser ablation and performing analytical chemistry. The system is based on an ion trap used in an ion-storage (IS) mode, coupled with a reflectron time of flight mass spectrometer (TOFMS). The LA-IS/TOF-MS can be used for MALDI or direct ionization of samples on a probe tip. This paper will describe the system configuration and related operating principles for measuring sensitive and accurate isotopic ratios. Preliminary measurements identified ultra-trace contaminants of Ag, Sn, and Sb in a Pb target with single laser-shot experiments. Survey analyses of uranyl acetate, hair samples, and mushrooms demonstrated that this technology can be applied to a wide range of sample materials

Edible insects: future prospects for food and feed security

This book draws on a wide range of scientific research on the contribution that insects make to ecosystems, diets, food security and livelihoods in both developed and developing countries

Parent-child Agreement on Health-Related Quality of Life in Children With Functional Constipation in Primary Care

Objective: Functional constipation (FC) has a major impact on the health-related quality of life (HRQoL) of children. The aim of this study was to evaluate parent-child agreement on HRQoL in children (8-17 years) with FC in primary care. Methods: Children diagnosed with FC by their clinician were eligible. HRQoL was measured with the Defecation Disorder List (DDL, score 0-100), and the EuroQol-5-Dimension-Youth Visual Analogue Scale (EQ-5D-Y-VAS, scale 0-100). Parent-child agreement was examined with discrepancy scores, intraclass correlation coefficients and Bland-Altman plots. Results: Fifty-six children, median age of 10 years (IQR 8-12) and their parents were included. Parent-child agreement at a group level was good, with an intraclass correlation coefficient of 0.80 (95% confidence interval 0.67 to 0.88) for the DDL, and 0.78 (95% confidence interval 0.65 to 0.87) for the EQ-5D-Y-VAS. Mean discrepancy scores for the DDL and EQ-5D-Y-VAS were small: -2.6 and -2.9, implying that parents were slightly more positive about the HRQoL than their children. Bland-Altman plots showed considerable discordance between individual parent-child pairs. Limits of agreement were -19.7 and 14.6 for the DDL and -27.6 and 21.8 for the EQ-5D-Y-VAS. Conclusions: There is good parent-child agreement on HRQoL in children with FC at group level. However, a substantial number of parent-child pairs differed considerably on their rating of the HRQoL of the child. Therefore, we recommend clinicians, if they want to have an impression of the impact of the FC on the HRQoL of the child, to ask both the child and the parent(s)