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As an adequate response to the new environmental conditions expected to arise due to climate change, our cities must be adapted to continue serving as pleasant and liveable spaces for its inhabitants and visitors. Large parts of our existing building stock remain unprepared/inadequate for the anticipated climatic changes. Adjustments are urgently needed. Within this paper a strategy has been elaborated about how retrofitting can significantly contribute to the climate change adaptation of our urban environments, as will be strongly required in the future. The focus of this study is directed to possible climate change related adaptations of multistorey residential buildings from the 19th and early 20th century in inner city areas of Germany. Building on the general principles of climate responsive and ecological architectural design and construction, it poses the following question: How can our existing buildings be transformed in order to explicitly reduce the impact of climate change on our built environments? Following an evaluation of the new climatic conditions influencing our buildings and looking into current knowledge of sustainable architecture and urban design and construction methods, this paper goes onto propose a set of guidelines for climate change adaptive retrofitting of 19th and 20th century multistorey residential buildings of inner-city areas of Germany. On one hand these optimization proposals are addressed to respond better to longer heat and dry periods in summer and to more extreme rainfall, snowfall and storms in the winter. On the other hand, these adjustments aim to build a criteria that serve to mitigate adverse effects of climate change, like an improvement of the buildings' energy performance and ecological efficiency. The results of this study demonstrate that the buildings focused on are well suited for retrofitting interventions, which would reduce the impact of climate change and which in parallel would constitute effective measures to strongly improve the buildings' ecological performance in general. [ABSTRACT FROM AUTHOR]

As an adequate response to the new environmental conditions expected to arise due to climate change, our cities must be adapted to continue serving as pleasant and liveable spaces for its inhabitants and visitors. Large parts of our existing building stock remain unprepared/inadequate for the anticipated climatic changes. Adjustments are urgently needed. Within this paper a strategy has been elaborated about how retrofitting can significantly contribute to the climate change adaptation of our urban environments, as will be strongly required in the future. The focus of this study is directed to possible climate change related adaptations of multistorey residential buildings from the 19th and early 20th century in inner city areas of Germany. Building on the general principles of climate responsive and ecological architectural design and construction, it poses the following question: How can our existing buildings be transformed in order to explicitly reduce the impact of climate change on our built environments? Following an evaluation of the new climatic conditions influencing our buildings and looking into current knowledge of sustainable architecture and urban design and construction methods, this paper goes onto propose a set of guidelines for climate change adaptive retrofitting of 19th and 20th century multistorey residential buildings of inner-city areas of Germany. On one hand these optimization proposals are addressed to respond better to longer heat and dry periods in summer and to more extreme rainfall, snowfall and storms in the winter. On the other hand, these adjustments aim to build a criteria that serve to mitigate adverse effects of climate change, like an improvement of the buildings' energy performance and ecological efficiency. The results of this study demonstrate that the buildings focused on are well suited for retrofitting interventions, which would reduce the impact of climate change and which in parallel would constitute effective measures to strongly improve the buildings' ecological performance in general. [ABSTRACT FROM AUTHOR]

Control of variables strategy is one of the strategies involved in scientific discovery and verification of hypotheses. It is important to assess the development of scientific thinking of Indonesian students, but we cannot find any measurement to assess scientific thinking particularly control of variables strategy for Indonesian students. The purpose of this study was to conduct the Indonesian adaptation of the Control of Variables Strategy Inventory (CVSI). The CVSI is a paper and pencil instrument that measures three sub-skills of control of variables strategy: Identification, Interpretation, and Understanding. The procedures of adaptation included translating the CVSI from Germany to the Indonesian language, evaluating the content and conceptual equivalence, and designing the final form of the inventory. To obtain the psychometry properties, a sample of 162 eighth grade students completed the inventory. The hypothesized measurement model was unidimensional and was examined using confirmatory factor analysis. Fit model was obtained after conducting modification of model as shown by fit index Chi-square=6.596, df=5, p=.252, GFI=.986, CFI=.983, TLI=.966, RMSEA=.041. The model comprises five Interpretation items with the lowest loading factor. 44 and Cronbach's alpha =. 610 as reliability coefficient. It seems that the items assessing Identification and Understanding skills that fit for 7, 8, and 9-grade students in Germany are not appropriate for eighth-grade students in Indonesia. Next research should examine whether this result is related to the development of the domain-general ability of reasoning, to domain-specific of physics knowledge, or to other factors. [ABSTRACT FROM AUTHOR]

This article raises the question whether there is in fact a specific field within civil engineering that may be connected to the impact of Covid-19, namely radon exposure in interior spaces in certain parts of the world. Radon exposure is particularly high in regions that have seen high mortality rates related to SARS-CoV-2. Examples of these include the Bergamo region in Italy and the Erz Mountains, the Fichtel Mountains or the Bavarian Forest in south-eastern Germany. But is there actually a correlation, or is this merely a coincidence? Is there in fact a causality? If so, constructional measures to protect against the decay products of radon in interior spaces would gain a new significance that goes beyond the realms of current knowledge. This article cannot provide a definitive answer to these questions due to the current patchiness of data in Germany. Nevertheless, this paper will use the data available to demonstrate that there is evidence of a possible correlation or causality between the two, and that this merits further research. [ABSTRACT FROM AUTHOR]

This article raises the question whether there is in fact a specific field within civil engineering that may be connected to the impact of Covid-19, namely radon exposure in interior spaces in certain parts of the world. Radon exposure is particularly high in regions that have seen high mortality rates related to SARS-CoV-2. Examples of these include the Bergamo region in Italy and the Erz Mountains, the Fichtel Mountains or the Bavarian Forest in south-eastern Germany. But is there actually a correlation, or is this merely a coincidence? Is there in fact a causality? If so, constructional measures to protect against the decay products of radon in interior spaces would gain a new significance that goes beyond the realms of current knowledge. This article cannot provide a definitive answer to these questions due to the current patchiness of data in Germany. Nevertheless, this paper will use the data available to demonstrate that there is evidence of a possible correlation or causality between the two, and that this merits further research. [ABSTRACT FROM AUTHOR]

Photovoltaics is one of the front-running renewable energy technologies, greatly contributing to the reduction in greenhouse gas emissions. With the aim for carbon neutrality ever larger photovoltaics plants are being built worldwide alongside an increasing number of small-scale Agri-Voltaics (APV) systems. Despite this trend, the impact of such systems on the environment remains scarcely studied. By means of lysimeters the effect of shading by solar panels on evapotranspiration (ET) and plant growth has been analyzed at a research station in Germany. During the measurement period which stretched from November 2019 to early April 2020, ET recorded at the area shaded by the panels was with 163 mm almost equal to ET at the reference site with 158 mm. However, percolation was found to be much higher at the reference site with 89.5 mm compared to the area below the panel where no seepage was detected. This difference was investigated by looking more in depth at the temporal evolution of ET, which showed to be season-dependent with lower ET below the panel than at the reference site during the growing season but higher ET below the panel the rest of the year. During the growing season, shading leads to a strong reduction of solar radiation received by the area below the panel resulting in lower soil temperatures and lower evapotranspiration than at the unshaded reference area. During the winter months in turn the panels raise soil temperatures by trapping outgoing radiation which results in higher evapotranspiration below the panels than at the reference area. The described effects of the panels on solar radiation and temperature have been studied at a conventional photovoltaics park and are described alongside the measurements from the lysimeter station within this paper. While at the end of the period of shading the height of rape was found to be on average 20 cm higher below the panel than at the reference site, rape yield in turn was lower assumingly due to a lack of light in the early stages of plant development. This paper presents the measurement results from the lysimeter station and discusses the underlying processes of changes in temperature and global radiation in respect to the soil-water-plant system. [ABSTRACT FROM AUTHOR]

Germany is one of the strongest countries in medical and health researches worldwide. With the rapid development and integration of digital technologies in this area, the medical methods and systems today are experiencing a fundamental change. Through people-oriented support policies, the federal government attempts to seize this opportunity and promotes the development of smart medicine and healthcare in Germany. This paper reviews comprehensively the strategic layout, guidelines, support areas and measures of the German federal government in the field of smart medicine and healthcare. [ABSTRACT FROM AUTHOR]

As part of the paper, the stress-strain state of the layer with spherical holes for lubricant was analyzed. A part of the sliding layer with one hole for lubricant was considered. The paper deals with an unfavorable case: the lack of lubrication in the recession. A comparison of deformation behavior of a sliding layer part made of three polymeric materials is presented: modified fluoroplastic, anti-friction fluoroplastic-based composite material with spherical bronze inclusions and molybdenum disulfide and high-modulus polyethylene produced in Germany. Physical and mechanical properties of the sliding layer materials were obtained experimentally. The frictional contact interaction of a sliding layer part with a rigid steel plate was considered with the friction coefficients obtained experimentally with and without lubrication on the mating surfaces. For the qualitative description of the numerical experiment, the experimental dependences of friction coefficients as a function of the pressure level were obtained, and approximating functions were constructed to obtain friction coefficients exceeding those technically possible in the field experiment. A series of numerical experiments on the deformation of a sliding layer part with a hole for lubricant with the use of a rigid steel plate and application of pressure from 5 to 90 MPa, which corresponds to the rated loads of the spherical support structures of the bridge spans. The deformed condition of the structure and contact zone parameters were analyzed. Influence of the sliding layer thickness on deformation characteristics of the contact node was studied. [ABSTRACT FROM AUTHOR]

A reference solar tower power plant with molten salt as heat transfer and storage medium has been designed. In addition to the general layout of this plant, the paper contains selected details about component sizing and optimization. The final layout and optimization of the least cost storage capacity for 2 different operating schemes has been checked by an annual yield calculation for an exemplary site in Morocco. [ABSTRACT FROM AUTHOR]

A 16.77 kW thermal power bayonet-tube reactor for the mixed reforming of methane using solar energy has been designed and modeled. A test bench for the experimental tests has been installed at the Synlight facility in Juelich, Germany and has just been commissioned. This paper presents the solar-heated reactor design for a combined steam and dry reforming as well as a scaled-up process simulation of a solar reforming plant for methanol production. Solar power towers are capable of providing large amounts of heat to drive high-endothermic reactions, and their integration with thermochemical processes shows a promising future. In the designed bayonet-tube reactor, the conventional burner arrangement for the combustion of natural gas has been substituted by a continuous 930 °C hot air stream, provided by means of a solar heated air receiver, a ceramic thermal storage and an auxiliary firing system. Inside the solar-heated reactor, the heat is transferred by means of convective mechanism mainly; instead of radiation mechanism as typically prevailing in fossil-based industrial reforming processes. A scaled-up solar reforming plant of 50.5 MWth was designed and simulated in Dymola® and AspenPlus®. In comparison to a fossil-based industrial reforming process of the same thermal capacity, a solar reforming plant with thermal storage promises a reduction up to 57 % of annual natural gas consumption in regions with annual DNI-value of 2349 kWh/m2. The benchmark solar reforming plant contributes to a CO2 avoidance of approx. 79 kilotons per year. This facility can produce a nominal output of 734.4 t of synthesis gas and out of this 530 t of methanol a day. [ABSTRACT FROM AUTHOR]

The centrifugal particle receiver “CentRec” is a solar tower receiver development by DLR based on a direct absorption receiver concept especially suitable for high temperature process heat and electricity generation applications. Ceramic particles are used as heat transfer and storage medium for temperatures up to 1000°C. A centrifugal particle receiver system including a CentRec receiver prototype has been tested up to 965°C average receiver outlet temperature in the research platform of DLR’s test facility Juelich Solar Tower, Germany. This paper describes the first test results with a focus on first operational experiences. [ABSTRACT FROM AUTHOR]

Over the last few years, companies and public authorities have become increasingly concerned about the security of the supply of mineral resources. Numerous elements are needed for all kinds of production in building, manufacturing and even the service sector. This is especially relevant for Germany because all metals and other high-tech resources important for modern manufacturing have to be imported. Secondary resources are the only option for Germany to satisfy some of the current demand with domestic resources. Resource-consuming industries face significant competition and a number of risks regarding security of supply. The industry considers the most relevant risks to be the increase and volatility of prices. Short-term reduction of supply is also among the most important risks. Numerous factors add up to the total risk of supply for every specific natural resource. The Resource Risk Index (RRI), developed by the Cologne Institute for Economic Research, is constructed to give guidance regarding the level of risks. With this indicator, we group 45 elements and define three classes of criticality: critical (red), less critical (orange) and not critical (yellow). Lithium-based batteries are current technologies for electricity storage, especially for mobile appliances like smartphones, mobile computers and electric vehicles. However, alternative storage concepts and new developments can be based on other natural resources. Therefore, other elements should be considered and their supply risks taken into account. This paper covers the main results (Resource Risk Index) of magnesium, cobalt, lithium, iron, lead, tantalum, nickel, manganese and aluminum. [ABSTRACT FROM AUTHOR]

In this paper ground based measurements of CPV module efficiency measured in Freiburg, Germany, are correlated to ground based measurements of DNI/GNI ratios and to space-borne observations of cirrus clouds obtained from the SEVIRI radiometer aboard the European geostationary Meteosat Second Generation satellite. The efficiency of CPV modules is found to decrease when the ratio of DNI to GNI increases. Furthermore, relatively high DNI to GNI ratios are observed when no cirrus clouds are present. In contrast, no direct correlation of efficiency and cirrus cloud cover was found for cases when cirrus clouds are detected by the satellite. Within this paper we provide explanations for this. The satellite measurement of cirrus clouds can be definitely applied for a qualitative evaluation of results derived by CPV module performance models. Furthermore the information about cirrus clouds can be of interest for an assessment of operation locations for CPV power plants. [ABSTRACT FROM AUTHOR]

The Forschungszentrum Ju¨lich GmbH (FZJ), together with the Aachen University Rheinisch-Westfaelische Technische Hochschule (RWTH) and the French Alternative Energies and Atomic Energy Commission (CEA Cadarache) are involved in a cooperation aiming at characterizing toxic and reactive elements in radioactive waste packages by means of Prompt Gamma Neutron Activation Analysis (PGNAA) [1]. The French and German waste management agencies have indeed defined acceptability limits concerning these elements in view of their projected geological repositories. A first measurement campaign was performed in the new Prompt Gamma Neutron Activation Analysis (PGNAA) facility called MEDINA, at FZJ, to assess the capture gamma-ray signatures of some elements of interest in large samples up to waste drums with a volume of 200 liter. MEDINA is the acronym for Multi Element Detection based on Instrumental Neutron Activation. This paper presents MCNP calculations of the MEDINA facility and quantitative comparison between measurement and simulation. Passive gamma-ray spectra acquired with a high purity germanium detector and calibration sources are used to qualify the numerical model of the crystal. Active PGNAA spectra of a sodium chloride sample measured with MEDINA then allow for qualifying the global numerical model of the measurement cell. Chlorine indeed constitutes a usual reference with reliable capture gamma-ray production data. The goal is to characterize the entire simulation protocol (geometrical model, nuclear data, and postprocessing tools) which will be used for current measurement interpretation, extrapolation of the performances to other types of waste packages or other applications, as well as for the study of future PGNAA facilities. [ABSTRACT FROM AUTHOR]

Photovoltaic technology has reached a point where its cost and capability make it one of a handful of carbon-free sources of electrical energy that could meet a meaningful fraction of US energy demand. In this paper we will first compare Photovoltaics with several other carbon free energy technologies, then look at the economics of Solyndra's rooftop photovoltaic solution as an example of the current state of the art, as well as the market dynamics that have resulted in dramatically faster adoption in Germany vs. the United States. [ABSTRACT FROM AUTHOR]

The OLYMPUS experiment at DESY, Hamburg, Germany will definitively determine the effect of two-photon exchange in elastic lepton-proton scattering by precisely measuring the ratio of positron-proton to electron-proton elastic unpolarized cross sections. In this paper, the physics motivation is summarized, aspects of the experimental setup are discussed and the current status and timeline of the project are reviewed. [ABSTRACT FROM AUTHOR]

Recent work has brought about a renewed interest in CO2 laser ablation studies of polyoxymethylene, due to its potential as a test target for enhancing modern understanding of the laser ablation process. In this paper, new results taken in air at atmosphere pressure are reported, including data measured at institutions in Germany and Japan, which increase the body of literature data on CO2 laser ablation of polyoxymethylene. The results are discussed in terms of aerospace parameters such as the momentum coupling coefficient and specific impulse, and are compared to a previous literature study. The threshold fluence is specified for ablation of polyoxymethylene by CO2 laser radiation. Fluences higher (and lower) than previously tested for CO2 laser ablation were studied herein, and record specific impulse values for CO2 laser ablation of flat polyoxymethylene are also reported here. [ABSTRACT FROM AUTHOR]

In this paper we show how to reconstruct the limit order book of the 30 stocks constituting the DAX30 index based on the trading protocol of the Xetra Trading System at the Frankfurt Stock Exchange. The algorithm used is innovative as it captures all trading phases, including auctions, and delivers a reconstruction of the orderbook either from a trader’s view or a supervisory view including hidden volume as well. Based on the rebuilt order book, liquidity dynamics are examined. In contrats to findings for dealer markets, past market returns play a minor role in the determination of liquidity and liquidity commonality in Xetra, a pure limit order book market. Consequently, we provide evidence that liquidity provision by multiple sources in Xetra mitigates systemic liquidity risk introduced by the interrelation of return and liquidity. [ABSTRACT FROM AUTHOR]

In this paper, a new system for improvement of the pulse contrast in CPA laser systems by use of an ultrafast OPA is reviewed together with a scheme to create sub-picosecond synchronized OPA pump pulses. The scheme is being implemented at the PHELIX facility at GSI-Darmstadt, Germany. [ABSTRACT FROM AUTHOR]

The cryogenic plant built for the HERA accelerator at DESY in Hamburg (Germany) is now in operation for more than two decades. The commercial process control system for the cryogenic plant is in operation for the same time period. Ever since the operator stations, the control network and the CPU boards in the process controllers went through several upgrade stages. Only the centralized Input/Output system was kept unchanged. Many components have been running beyond the expected lifetime. The control system for one at the three parts of the cryogenic plant has been replaced recently by a distributed I/O system. The I/O nodes are connected to several Profibus-DP field busses. Profibus provides the infrastructure to attach intelligent sensors and actuators directly to the process controllers which run the open source process control software EPICS. This paper describes the modification process on all levels from cabling through I/O configuration, the process control software up to the operator displays. [ABSTRACT FROM AUTHOR]

At the new research reactor FRM II in Garching near Munich the beam guide with the highest cold neutron flux is dedicated to Prompt Gamma-ray Activation Analysis (PGAA) and related neutron capture experiments. We have designed a partially ballistic form of the neutron guide with the aim of concentrating the cold neutrons at the target position of the PGAA experiment. The cold neutron flux with a mean energy of only 1.83 meV was measured about 10.5 cm far from the second exit window and reached intensity of 1.7×1010 n/cm2 s at a 2 mm×2 mm gold foil. The PGAA installation is now prepared for three different kinds of measurements—standard PGAA, Neutron Tomography of small samples and position sensitive PGAA, or PGAI for short. We have also measured γγ coincidences in 77Ge. In this paper, we want to introduce the PGAA facility, show the diversity of the recently performed experiments and discuss further possibilities. [ABSTRACT FROM AUTHOR]

This paper presents some applications of ultrasonic (UT) simulation codes developed at IZFP, Germany and at CEA LIST, France, those latter being integrated into the CIVA software platform. These UT simulation codes are dedicated to the prediction of echo-responses from flaws. Results given and discussed are those obtained for the various problems of the 2007 UT Benchmark modeling session. They concern the responses from flat-bottomed holes inside curved blocks (concave or convex) inspected with immersed probes. The simulation codes are used to investigate the influence of the curvature upon the amplitude response of the flaw with respect to a flat specimen, used as a reference. Comparison with experimental results is also discussed. [ABSTRACT FROM AUTHOR]

Virtual Compton scattering off the proton has been studied at Q2 = 0.33 (GeV/c)2 at MAMI (Mainz, Germany). This paper reports two different experiments. The goal of the experiments is the measurement of the double polarized evector p → e′pvector ′γ reaction below pion production threshold and the (beam) single spin asymmetry for evector p → e′p′γ above the π0 threshold. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Silicon Photomultipliers (SiPM) are novel detectors for low level light detection based on arrays of avalanche photodiodes operating in Geiger mode. Offering good characteristics (fast response, high gain, photon counting capability, insensitivity to magnetic fields, low voltage operation) they have the potential to replace classical photomultipliers (PMT) in many applications. Drawbacks are dark rate and optical cross talk. Though their quantum efficiency is already comparable or better than that of bialkali PMT it is still limited by the structures on the light sensitive front surface. A new concept, presently developed at the Max-Planck semiconductor laboratory, allows boosting the efficiency to almost 100%. Using a fully depleted substrate the light enters through the unstructured backside. A drift diode structure collects the electrons on a small “point like” avalanche structure for multiplication. Engineering the thin entrance window at the backside using antireflective layers a high efficiency can be achieved in a wide wavelength range (300–1000nm). The paper will summarize the status of front illuminated SiPMs and report on the development of the backside illuminated devices. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

At the Max-Planck-Institut für Kernphysik in Heidelberg a next generation electrostatic storage ring for cryogenic temperatures is under development. The main focus of this unique machine is the research on ions, molecules and clusters up to bio molecules in the energy range of 20–300 keV at low temperatures down to 2 Kelvin. The achievement of this low temperature for all material walls seen by the ions in the storage ring will allow novel experiments to be performed, such as rotational and vibrational state control of molecular ions and their interaction with ultra-low energy electrons and laser radiation. The low temperature of the storage ring not only causes a strong reduction of black body radiation incident onto the stored particles, but also acts as a large cryopump, expected to lead to a vacuum in the 10–15 mbar range. In this paper the cryogenic concept of the storage ring and the related vacuum design will be presented. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

A beam test of a superconductive undulator (100 periods, 14 mm period length) is in preparation at the 2.5 GeV storage ring ANKA in Karlsruhe. The aim of this test is to study the behaviour of a cold-bore superconductive undulator in a storage ring (study of the influence of the beam induced heating and heating by synchrotron radiation from downstream magnets) and to conduct an analysis of the quality of the emitted spectrum. A coil at the entrance and a single superconductive dipole correction coil covering the whole undulator is provided to minimize the first and second integral. A section of this paper is devoted to the discussion of a more elaborate correction system for future undulators. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

High energy photon colliders (γγ, γe) based on backward Compton scattering of laser light is a very natural addition to e[sup +]e[sup -] linear colliders. In this report we consider mainly this option for the TESLA project. Recent study has shown that the horizontal emittance in the TESLA damping ring can be further decreased by a factor of four. In this case the γγ luminosity luminosity in the high energy part of spectrum can reach 0.3–0.5 L[sub e[sup +]e[sup -]]. Typical cross sections of interesting processes in γγ collisions are higher than those in e[sup +]e[sup -] collisions by about one order of magnitude, so the number of events in γγ collisions will be more that in e[sup +]e[sup -] collisions. The key new element in photon colliders is a very powerful laser system. The most straightforward solution is “an optical storage ring (optical trap)” with diode pumped laser injector which is today technically feasible. This paper briefly reviews the status of a photon collider based at TESLA, its possible parameters. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]