Small diameter fibres as new wick material for capillary-driven heat pipes

Papers presented to the 11th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 20-23 July 2015.Heat pipes with a wick material consisting of small diameter metal fibres of 12 μm are investigated. The container material is copper and the working fluid is water. The fibre mesh heat pipe is compared with two other wick structures: a screen mesh (145 meshes per inch) and a sintered powder wick. All three heat pipes have an outer diameter of 6 mm, a length of 200 mm. The heat pipes are tested in a vertical orientation, both gravity-opposed and gravity-assisted. In the gravity-opposed orientation the heat pipes are tested for a heat input up to 50 W and an operating temperature of 70°C. In the gravity-assisted orientation the heat pipes are tested up to 160 W and 120°C. The thermal resistance and the temperature difference between evaporator and condenser are used as performance indicators. For the gravity-assisted orientation, the screen mesh wick clearly outperforms the fibre and sintered powder wick, due to its higher permeability and better ability to distribute the working fluid over the circumference of the wick. For the gravity-opposed orientation, the fibre and screen mesh heat pipe perform equally well. Both have a lower thermal resistance than the sintered powder heat pipe, as the small diameter fibres and fine mesh create more and very small capillary channels in comparison with the sintered powder wick.am201

The Next Linear Collider Test Accelerator

During the past several years, there has been tremendous progress on the development of the RF system and accelerating structures for a Next Linear Collider (NLC). Developments include high-power klystrons, RF pulse compression systems and damped/detuned accelerator structures to reduce wakefields. In order to integrate these separate development efforts into an actual X-band accelerator capable of accelerating the electron beams necessary for an NLC, we are building an NLC Test Accelerator (NLCTA). The goal of the NLCTA is to bring together all elements of the entire accelerating system by constructing and reliably operating an engineered model of a high-gradient linac suitable for the NLC. The NLCTA will serve as a testbed as the design of the NLC evolves. In addition to testing the RF acceleration system, the NLCTA is designed to address many questions related to the dynamics of the beam during acceleration. In this paper, we will report on the status of the design, component development, and construction of the NLC Test Accelerator

Cause of Death and Predictors of All-Cause Mortality in Anticoagulated Patients With Nonvalvular Atrial Fibrillation : Data From ROCKET AF

M. Kaste on työryhmän ROCKET AF Steering Comm jäsen.Background-Atrial fibrillation is associated with higher mortality. Identification of causes of death and contemporary risk factors for all-cause mortality may guide interventions. Methods and Results-In the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF) study, patients with nonvalvular atrial fibrillation were randomized to rivaroxaban or dose-adjusted warfarin. Cox proportional hazards regression with backward elimination identified factors at randomization that were independently associated with all-cause mortality in the 14 171 participants in the intention-to-treat population. The median age was 73 years, and the mean CHADS(2) score was 3.5. Over 1.9 years of median follow-up, 1214 (8.6%) patients died. Kaplan-Meier mortality rates were 4.2% at 1 year and 8.9% at 2 years. The majority of classified deaths (1081) were cardiovascular (72%), whereas only 6% were nonhemorrhagic stroke or systemic embolism. No significant difference in all-cause mortality was observed between the rivaroxaban and warfarin arms (P=0.15). Heart failure (hazard ratio 1.51, 95% CI 1.33-1.70, P= 75 years (hazard ratio 1.69, 95% CI 1.51-1.90, P Conclusions-In a large population of patients anticoagulated for nonvalvular atrial fibrillation, approximate to 7 in 10 deaths were cardiovascular, whereasPeer reviewe

Mobile mapping and the use of backscatter data for the modelling of intertidal zones of beaches

Mobile mapping with laser scanning is frequently limited to the sole geometric reconstruction of objects or surfaces. In the special case of the construction of Digital Elevation Models (DEMs) of intertidal zone of beaches, this task is known to be very challenging. In the context of the interdisciplinary research project named 'SeArch', which aims at documenting and managing archaeological patrimony in the North Sea, a field campaign was organized in the summer of 2013. During this campaign, an amphibious vehicle (ARGO) was equipped with a Terrestrial Laser Scanner (TLS) in profiler mode, an Inertial Measurement Unit (IMU), a Real-Time Kinematic Global Navigation Satellite System (RTK GNSS) and a PC hydrographic data acquisition software and huge storage capacity. Based on previous research, this configuration appeared to have the best performance under the environmental conditions at the Belgian North Sea coast. Especially for the intertidal zones of beaches, the use of this mobile platform resulted in very promising results from a geometrical point of view. A summary of the results of the campaign is presented in this paper. Although the focus of this campaign was on the construction of DEMs with a high resolution and a high accuracy, the used Leica HDS 6200 phase-based laser scanner also returned a backscatter value for each measured point. A provisional analysis of these values suggested a relation between the physical properties of the reflecting surface and the registered backscatter values. However, earlier studies have also demonstrated the influence of the incidence angle and measured distance on this backscatter value. As will be discussed in this paper, a correction function can be defined that takes these parameters into account as weights for corrected backscatter data. In combination with the commonly used point cloud, the corrected values allow the calculation of false-color composites of the measured surface and the detection and description of features

Synthetic training data generation for activity monitoring and behavior analysis

This paper describes a data generator that produces synthetic data to simulate observations from an array of environment monitoring sensors. The overall goal of our work is to monitor the well-being of one occupant in a home. Sensors are embedded in a smart home to unobtrusively record environmental parameters. Based on the sensor observations, behavior analysis and modeling are performed. However behavior analysis and modeling require large data sets to be collected over long periods of time to achieve the level of accuracy expected. A data generator - was developed based on initial data i.e. data collected over periods lasting weeks to facilitate concurrent data collection and development of algorithms. The data generator is based on statistical inference techniques. Variation is introduced into the data using perturbation models. © Springer-Verlag Berlin Heidelberg 2009

Hemin Reconstitutes Proton Extrusion in an H(+)-ATPase-Negative Mutant of Lactococcus lactis

H(+)-ATPase is considered essential for growth of Lactococcus lactis. However, media containing hemin restored the aerobic growth of an H(+)-ATPase-negative mutant, suggesting that hemin complements proton extrusion. We show that inverted membrane vesicles prepared from hemin-grown L. lactis cells are capable of coupling NADH oxidation to proton translocation