Navigation in a library using smartphones

In these times, when everyone wants to do as much work as possible in the least amount of time, it is important to make the workflow as efficient as possible. Spending an unnecessary amount of time looking for things is therefore contra productive. Using the library HafenCity University Hamburg (HCU) as an example, this paper shows how the time required to find a book can be reduced by introducing an indoor navigation system for that purpose. Acceleration sensors are used to realize a step counter. In combination with gyroscope data a dead reckoning can be carried out. The height information is derived of barometric measurements. For additional support, routing graphs are used to constrain the walking direction. With this setup and the additional topological we achieve deviations between last estimated to wanted position less than two meters

Monitoring of the Refraction Coefficient in the Lower Atmosphere Using a Controlled Setup of Simultaneous Reciprocal Vertical Angle Measurements

A great deal of empirical studies have investigated the characteristics of terrestrial refraction. However, only few of these are concerned with short-term fluctuations of refraction influences. The aim of the present work is to analyze the short-term characteristics (amplitudes and variations at scales of minutes to hours) of terrestrial refraction in the lower atmosphere around 1.8 m above the grass surface. We apply the known method of simultaneous reciprocal vertical angle measurements to derive time series of the refraction coefficient k as a measure for refraction. Our study uses a new setup of two pairs of total stations for parallel observations of the refraction coefficient along adjacent lines of sight. Such a controlled experiment not only allows us to determine refraction coefficients independently but also to assess measurement errors from the residuals between refraction coefficient pairs.Over five observation days in the summer of 2008, a total of 33 h of parallel observation data of the refraction coefficient were collected at sampling frequencies of 1 min. On one observation day, unique parallel observations of the refraction coefficient along three lines of sight with a total of six total stations were possible. For mostly sunny days, we found wave-like and sawtooth-like fluctuations of the refraction coefficient with amplitudes of 1–1.5 at time scales of 10–30 min. On cloudy days, the amplitudes of fluctuations were on the order of 0.5. Our refraction experiments show a variation range of k between −4 and +16 near the ground on sunny summer days. This equates to vertical temperature gradients between −0.5 and −0.1 K/m during the day and 1–2 K/m shortly after sunset. Cloud cover reduces the variability of k to a range of −2 to +5. Our results show that the frequently used Gaussian refraction coefficient of +0.13 is not suited for describing refraction effects in the lower atmosphere. As a conclusion, our results may be helpful to better assess the role of refraction in near-ground precision surveys, such as geometric levelling or trigonometric heighting

Modellierung der Deformation eines Stahlträgers durch indirekte Dehnungsmessungen

Die Durchbiegung von Stahlträgern ist bei der Überwachung von Bauwerken von besonderem Interesse, um Aussagen zur Stabilität dieser machen zu können. In vielen Fällen ist ein direktes Messen der Durchbiegung nicht möglich, so dass diese über andere Messgrößen bestimmt werden muss und eine Beziehung zwischen verschiedenen Größen zu modellieren ist. Längsdehnungen und Durchbiegungen stehen vereinfacht ausgedrückt für den Fall der mittleren Durchbiegung bei Stahlträgern in einer linearen Beziehung. Werden für die Sensoren aber auf Adaptern am Träger installiert, dann muss der Einfluss dieser im Dehnungs-Durchbiegungs-Modell berücksichtigt werden. Die empirische Bestimmung des Einflusses und die Erstellung eines einfachen Kongruenzmodells für diesen Fall liegen im Fokus dieser Untersuchungen

Comparative transcriptomics and proteomics of p-hydroxybenzoate producing Pseudomonas putida S12: novel responses and implications for strain improvement

A transcriptomics and proteomics approach was employed to study the expression changes associated with p-hydroxybenzoate production by the engineered Pseudomonas putida strain S12palB1. To establish p-hydroxybenzoate production, phenylalanine-tyrosine ammonia lyase (pal/tal) was introduced to connect the tyrosine biosynthetic and p-coumarate degradation pathways. In agreement with the efficient p-hydroxybenzoate production, the tyrosine biosynthetic and p-coumarate catabolic pathways were upregulated. Also many transporters were differentially expressed, one of which—a previously uncharacterized multidrug efflux transporter with locus tags PP1271-PP1273—was found to be associated with p-hydroxybenzoate export. In addition to tyrosine biosynthesis, also tyrosine degradative pathways were upregulated. Eliminating the most prominent of these resulted in a 22% p-hydroxybenzoate yield improvement. Remarkably, the upregulation of genes contributing to p-hydroxybenzoate formation was much higher in glucose than in glycerol-cultured cells