Schneefernerhaus as a mountain research station for clouds and turbulence

Cloud measurements are usually carried out with airborne campaigns, which are expensive and are limited by temporal duration and weather conditions. Ground-based measurements at high-altitude research stations therefore play a complementary role in cloud study. Using the meteorological data (wind speed, direction, temperature, humidity, visibility, etc.) collected by the German Weather Service (DWD) from 2000 to 2012 and turbulence measurements recorded by multiple ultrasonic sensors (sampled at 10 Hz) in 2010, we show that the Umweltforschungsstation Schneefernerhaus (UFS) located just below the peak of Zugspitze in the German Alps, at a height of 2650 m, is a well-suited station for cloud–turbulence research. The wind at UFS is dominantly in the east–west direction and nearly horizontal. During the summertime (July and August) the UFS is immersed in warm clouds about 25 % of the time. The clouds are either from convection originating in the valley in the east, or associated with synoptic-scale weather systems typically advected from the west. Air turbulence, as measured from the second- and third-order velocity structure functions that exhibit well-developed inertial ranges, possesses Taylor microscale Reynolds numbers up to 104, with the most probable value at ~ 3000. In spite of the complex topography, the turbulence appears to be nearly as isotropic as many laboratory flows when evaluated on the "Lumley triangle"

Schneefernerhaus as a mountain research station for clouds and turbulence

Cloud measurements are usually carried out with airborne campaigns, which are expensive and are limited by temporal duration and weather conditions. Ground-based measurements at high-altitude research stations therefore play a complementary role in cloud study. Using the meteorological data (wind speed, direction, temperature, humidity, visibility, etc.) collected by the German Weather Service (DWD) from 2000 to 2012 and turbulence measurements recorded by multiple ultrasonic sensors (sampled at 10 Hz) in 2010, we show that the Umweltforschungsstation Schneefernerhaus (UFS) located just below the peak of Zugspitze in the German Alps, at a height of 2650 m, is a well-suited station for cloud-turbulence research. The wind at UFS is dominantly in the east-west direction and nearly horizontal. During the summertime (July and August) the UFS is immersed in warm clouds about 25 % of the time. The clouds are either from convection originating in the valley in the east, or associated with synoptic-scale weather systems typically advected from the west. Air turbulence, as measured from the second- and third-order velocity structure functions that exhibit well-developed inertial ranges, possesses Taylor microscale Reynolds numbers up to 104, with the most probable value at ∼ 3000. In spite of the complex topography, the turbulence appears to be nearly as isotropic as many laboratory flows when evaluated on the Lumley triangle

Schneefernerhaus as a mountain research station for clouds and turbulence

Cloud measurements are usually carried out with airborne campaigns, which are expensive and are limited by temporal duration and weather conditions. Ground-based measurements at high-altitude research stations therefore play a complementary role in cloud study. Using the meteorological data (wind speed, direction, temperature, humidity, visibility, etc.) collected by the German Weather Service (DWD) from 2000 to 2012 and turbulence measurements recorded by multiple ultrasonic sensors (sampled at 10 Hz) in 2010, we show that the Umweltforschungsstation Schneefernerhaus (UFS) located just below the peak of Zugspitze in the German Alps, at a height of 2650 m, is a well-suited station for cloud-turbulence research. The wind at UFS is dominantly in the east-west direction and nearly horizontal. During the summertime (July and August) the UFS is immersed in warm clouds about 25 % of the time. The clouds are either from convection originating in the valley in the east, or associated with synoptic-scale weather systems typically advected from the west. Air turbulence, as measured from the second- and third-order velocity structure functions that exhibit well-developed inertial ranges, possesses Taylor microscale Reynolds numbers up to 104, with the most probable value at ∼ 3000. In spite of the complex topography, the turbulence appears to be nearly as isotropic as many laboratory flows when evaluated on the Lumley triangle

Turbulence-induced cloud voids: observation and interpretation

The phenomenon of cloud voids, i.e., elongated volumes inside a cloud that are devoid of droplets, was observed with laser sheet photography in clouds at a mountain-top station. Two experimental cases, similar in turbulence conditions yet with diverse droplet size distributions and cloud void prevalence, are reported. A theoretical explanation is proposed based on the study of heavy inertial sedimenting particles inside a Burgers vortex. A general conclusion regarding void appearance is drawn from theoretical analysis. Numerical simulations of polydisperse droplet motion with realistic vortex parameters and Mie scattering visual effects accounted for can explain the presence of voids with sizes similar to that of the observed ones. Clustering and segregation effects in a vortex tube are discussed for reasonable cloud conditions.</p

Preparing construction supply chains for blockchain technology:An investigation of its potential and future directions

Blockchain, a peer-to-peer, controlled, distributed database structure, has the potential to profoundly affect current business transactions in the construction industry through smart contracts, cryptocurrencies, and reliable asset tracking. The construction industry is often criticized for being slow in embracing emerging technologies and not effectively diffusing them through its supply chains. Often, the extensive fragmentation, traditional procurement structures, destructive competition, lack of collaboration and transparency, low-profit margins, and human resources are shown as the main culprits for this. As blockchain technology makes its presence felt strongly in many other industries like finance and banking, this study investigates the preparation of construction supply chains for blockchain technology through an explorative analysis. Empirical data for the study were collected through semistructured interviews with 17 subject experts. Alongside presenting a strengths, weaknesses, opportunities, and threats analysis (SWOT), the study exhibits the requirements for and steps toward a construction supply structure facilitated by blockchain technology

Influence of cell dissociation procedures on the tumorigenicity of Simian Virus 40 transformed fibroblasts

Mouse fibroblasts transformed by Simian Virus 40 (SV40) were examined for tumor forming ability in syngeneic BALB/c mice following dissociation from tissue culture dishes by two procedures. A significantly greater in vivo proliferative capacity was observed for cells dissociated by the tryspin-EDTA procedure, with the injected cell dose for tumor production in 50 percent of recipient mice (the TPD$sub 50$) being 16-fold lower than the TPD$sub 50$ for cells dissociated by the EDTA procedure. Host immunosuppression with 300 rad whole-body $gamma$ irradiation led to a significant 7-fold decrease in the TPD$sub 50$ for cells dissociated by the EDTA procedure, while no significant decrease in TPD$sub 50$ was observed for cells dissociated by the tryspin-EDTA procedure. (auth

Influence of cell dissociation procedures on the tumorigenicity of Simian Virus 40 transformed fibroblasts

Mouse fibroblasts transformed by Simian Virus 40 (SV40) were examined for tumor forming ability in syngeneic BALB/c mice following dissociation from tissue culture dishes by two procedures. A significantly greater in vivo proliferative capacity was observed for cells dissociated by the tryspin-EDTA procedure, with the injected cell dose for tumor production in 50 percent of recipient mice (the TPD$sub 50$) being 16-fold lower than the TPD$sub 50$ for cells dissociated by the EDTA procedure. Host immunosuppression with 300 rad whole-body $gamma$ irradiation led to a significant 7-fold decrease in the TPD$sub 50$ for cells dissociated by the EDTA procedure, while no significant decrease in TPD$sub 50$ was observed for cells dissociated by the tryspin-EDTA procedure. (auth

Surface Temperature Effects on Boundary-Layer Transition at Various Subsonic Mach Numbers and Streamwise Pressure Gradients

The effect on transition of a non-adiabatic surface was systematically studied in the present experimental work in combination with the influence of variations in Mach number and pressure gradient. The investigations were carried out in a (quasi-) two-dimensional flow at four different subsonic Mach numbers and chord Reynolds numbers up to 13 million. Various streamwise pressure gradients and wall temperature ratios were examined. The experiments were conducted in the low-turbulence Cryogenic Ludwieg-Tube Göttingen on a two-dimensional flat-plate configuration designed for an essentially uniform pressure gradient on the model upper surface. The model was instrumented with a temperature-sensitive paint to measure globally and non-intrusively the surface temperature and thus the boundary-layer transition. A marked influence of a variation in the wall temperature ratio on transition was observed for all considered Mach numbers, being this effect more pronounced at lower Mach numbers. The measured transition locations were also correlated with the results of linear local stability analysis. Smaller disturbance amplification factors were found at transition for larger Mach numbers and, in most of the examined cases, for smaller wall temperature ratios and stronger flow acceleration

Trustworthy product lifecycle management using blockchain technology : experience from the automotive ecosystem

Rooted on the principle “from cradle to grave”, the lifecycle-driven approach to managing products like automobiles and related services has been recognised as a pivotal approach in research and practice. Digital technologies have continuously fostered the further development of product lifecycle management (PLM) in recent decades. Nowadays, novel disruptive technologies offer even more important advances for providers and users of such solutions alike. For the case of the automotive industry, intelligent products have created seamless visibility over the vehicle operations, big data techniques allow for the creation of sound insights, and blockchain technology holds the potential for trustworthy vehicle data management. The economic potential of preventing fraud and providing correct data is vast. Solely for the case of mileage manipulation, financial damage of around 9 billion Euro is estimated for the European Union. Accurate data establishing the basis for digital services potentially delivers a global revenue in the 100 billion Euro range. While these benefits of decentralised and encrypted data management are clear in theory, less knowledge is available about the practical implementation of such blockchain-based solutions. The purpose of this case study is to reflect experiences from a project in the setting of a leading automotive player which targets development and roll out of a trustworthy product lifecycle management using blockchain technology. Specifically, the study at hand mirrors insights from the automotive ecosystem focusing on the business-to-business context, involving fleets, OEMs, and repair shops. Such a case study seems valuable as research and practice call for real-world insights on blockchain applications especially outside the financial industry. After this abstract, the second part of the case study provides a sketch of product lifecycle management and blockchain technology itself. In the third part, further details on the case of vehicle operations in the automotive ecosystem are given. The fourth part illustrates findings in terms of experience from the realisation of trustworthy product lifecycle management. In the fifth part, a discussion on the diverse and relevant hurdles to overcome is followed by a description of limitations and a view towards the future