32 research outputs found
Horizontal integration in markets for complementary components and vertical product differentiation: A case-based analysis in the semiconductor industry
No full textObservations of recent mergers and acquisitions (M&A) in the semiconductor and computer industry indicate that activities concentrate on the technology leaders in this market. The author examines the influence of players’ heterogeneous product technologies on their involvement in M&A. He provides a rationale for the influence with the help of a case study and a two-stage non cooperative game. The case is about an acquisition wave between suppliers in two semiconductor component markets. Exemplary for the whole industry, acquisition activities concentrated on the technology leader in one of the component markets. Technological heterogeneity is represented within a vertically differentiated product space in the model
Following the Sun: Low-energy, mixed-use, student housing redesign with a Climate Adaptive Facade
No full textThe aim of this graduation project is to use an existing vacant building in a lifeless area of Amsterdam and create a multi-functional building with a mixture of activities that will benefit both the social and aesthetic aspects of the area, and will attract more people to visit or leave there. It will be a starting point for others to continue. The design strategy aims to apply as minimum structural changes as possible, taking advantage of the specific layouts of the existing building and be an energy efficient, low to zero carbon, climate adaptive building. This will be achieved with smart combinations of various functions having in mind the energy infrastructure, the structure, the interior and most importantly the façade.Architectural EngineeringArchitectural Engineering and TechnologyArchitecture and The Built Environmen
GPU Implementation of Grid Search based Feature Selection: Using Machine Learning to Predict Hydrocarbons using High Dimensional Datasets
No full textTo optimize the exploitation of oil and gas reservoirs both on- and offshore, Biodentfiy has developed a method to predict prospectivity of hydrocarbons before drilling. This method uses microbiological DNA analysis of shallow soil or seabed samples to detect vertical upward microseepage from hydrocarbon accumulations, which change the composition of microbes at the surface.Microbiological DNA analysis of shallow soil or seabed samples results in a high-dimensional dataset, which is interpreted using machine learning. Using the machine learning method Elastic Net, features (microbes) are selected from an existing DNA database to classify new shallow soil or seabed samples. Multiple models, each with a different combination of externally set parameters (called hyperparameters), are trained to improve accuracy, essentially creating a grid of models. The aim of this thesis is to investigate if it is possible to accelerate feature selection on high-dimensional datasets by implementing a parallel design on a GPU to train this grid of models, and to investigate the performance of this GPU implementation. Inspired by an implementation called Shotgun, which is able to improve performance by exploiting parallelism across features when training a single model on a CPU, an implementation, named GPU Shotgun (GPU-SG) was devised, which could exploit parallelism across samples, features, and multiple models in the grid (of combinations of hyperparameters). Depending on the size of the grid and the hardware, using GPU-SG, a speedup of between 0.2 and 5.26 can be reached for sparse datasets (a datasets with lots of 0 values) when compared to standard CPU implementations. When considering dense datasets (a dataset with few 0 values), using GPU-SG, a speedup of between 0.5 and 10 can be achieved. The amount of memory available to store a dataset is lower for GPU's than for a CPU, and currently the design is limited by this, because the design does not allow a dataset that is larger than the memory available. GPU-SG can be used to design improved implementations, which reduce the time when the GPU or CPU is idle to improve performance.Computer Engineerin
Prediction and modeling with partial dependencies
Get PDFThe author consider a binary classification problem with a feature vector of high dimensionality. Spam mail filters are a popular example hereof. A Bayesian approach requires us to estimate the probability of a feature vector given the class of the object. Due to the size of the feature vector this is an unfeasible task. A useful approach is to split the feature space into several (conditionally) independent subspaces. This results in a new problem, namely how to find the ldquobestrdquo subdivision. In this paper the author consider a weighing approach that will perform (asymptotically) as good as the best subdivision and still has a manageable complexity
Development of a Robust Reference Path Generator for Lateral Vehicle Control
No full textAutomated vehicle control provides advantages in transport efficiency, redundancy, human-safety, flexibility, and parallelism. Extensive research has been dedicated to direct-following lateral control methods, using a single preview point as reference signal. However, these methods give rise to significant tracking errors. As alternative to a single point, a continuous path can be used as reference signal for vehicle control. Using a continuous reference path, accurate and comfortable control actions can be computed, while avoiding reference tracking errors. Therefore, robust reference path generation is an essential part of lateral vehicle control.The goal of this research is to develop a generic, robust reference path generator for lateral vehicle control. Currently in path generation, the state-of-the-art method is based on repetitive polynomial fitting. This method inherently contains two main weaknesses. Firstly, it is not robust to sensor noise and other real-world disturbances. Secondly, as a result of the repetitive fitting, a discontinuous path is generated. This is undesirable, because it leads to an unfeasible reference path, since vehicles can only produce and track continuous trajectories. Moreover, a discontinuous reference path results in the need for path smoothing when used in comfortable lateral vehicle control. Fundamentally, this smoothing leads to inaccurate control, caused by manipulation of the original, discontinuous reference path. To overcome these weaknesses, a new Model-based Path Generation method is presented.The development of a new, generic method for robust path generation is the main contribution of this research. This new path generation method is capable of producing feasible vehicle trajectories based on unfeasible waypoints. The performance of this method is evaluated in simulations and experiments, benchmarking it against polynomial fitting path generation. Furthermore, path generation robustness is assessed based on the outcome of a disturbance sensitivity analysis. The results are in accordance with the hypothesis stating that the new method outperforms the benchmark method in terms of path accuracy, robustness, continuity, and general applicability
Do Financial Bonuses to Employees Reduce their Absenteeism? Outcome of a Lottery
Get PDFIn this paper, we present evidence on the effect of greater numbers of police personnel on victimisation of crime and experience of nuisance. We make use of individual data from a Dutch victimisation survey unique in its size, duration and scope. By using individual victimisation data we provide evidence on the effects of police on nuisance rather than 'hard crime' only, we circumvent measurement error common to police statistics, and we are able to control for both individual and municipality characteristics.Technology, Policy and Managemen
Circularity; the reuse of an office building
No full textThis graduation project addresses two problems, the high vacancy rate of office buildings in the Netherlands, and the linear approach of take-make-use-dispose, which results in the depletion of natural resources. In this project, an office building is transformed for other multiple functions with the old materials of the building in consideration. Research is done for materials within the circularity approach. For the new built part of the building only materials are used which are 100% recyclable or 100% biodegradable and demountable. Materials which doesn't release any harmful gasses during the use. The old materials are assessed whether these are reusable, recyclable or biodegradable. If this is not possible, I have tried to keep these materials in place in the design, without demolishing. A new future is searched for the materials which are reusable.Architectural EngineeringArchitectural Engineering and TechnologyArchitecture and The Built Environmen
A Low-cost Tracking Solution For VR Headsets
No full textInaccurate and slow positional tracking are fundamental problems of low-cost VR solutions. These factors can induce motion sickness and therefore significantly deteriorate the user experience. There are already a variety of solutions available to track the position of a VR HMD, some of which can be made robust andlow-latency by inexpensive means.This thesis proposes a low-cost, outside-in, optical tracking solution. As optical sensor a stationary camera with an IR pass filter is used to capture an array of IR LEDs, which are integrated at strategic locations within the frame of the HMD. By using the OpenCV library the 3D pose of the LEDs can be estimated, and used to change the perspective of the user within the virtual world.In particular, this tracking solution incorporates a fast, cost-effective, modified camera, capable of capturing over 180 frames per second. With this camera and a custom designed polyhedral structure to incorporate the LEDs, the LED array can be calibrated quickly and tracked accurately even when oriented at an obtuseangle with the camera. The high frame rate also allows for a redundancy in pose estimations, obtained by a mix of algebraic and iterative PnP solvers to further improve numerical stability and accuracy.The tracking algorithm accurately tracks the developed prototype at short distances, even when placed in a noisy environment. The calibration procedure can also be performed fast, so that tracking can be resumed within a second when tracking has been lost due to occlusion. Recommendations for further improvements would be to integrate an IMU to provide tracking information in case that the HMD becomes occluded, and to overall improve tracking of rotational movement. Also, a higher resolution optical sensor should beused to improve the range of this tracking solution.Electrical Engineerin
Nogmaals ‘het geheim van het oude heideland’
No full textThe author mentions the identification of Petrus Heiner as the true author of a boys’ book published by Piet Sjoerdsma in 1936. The book describes the adventures of four highschool boys camping near the Drenthe village of Havelte. Many local characters can be recognized. The leader of the criminal gang exposed by the boys appears to be modelled on the successful amateur archeologist G.H. Voerman
Catalysing the energy service market: The role of intermediaries
Get PDFAbstractThe UK market for energy service contracts is expanding, owing in part to the emergence of intermediaries for those contracts in different parts of the public sector. These intermediaries combine a legal framework for establishing contracts with an organisational framework that facilitates contract negotiation and execution. This paper examines the nature and operation of these intermediaries in more detail, including their achievements to date and their similarities and differences. It uses ideas from transaction cost economics to develop a theoretical model of the contracting decision and shows how intermediary organisations can lower the transaction costs incurred by both clients and contractors, thereby increasing the viability of contracting. The paper argues that intermediaries can play an important role in expanding the market for energy service contracts, and hence in delivering cost-effective energy efficiency improvements throughout the public sector
