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Spatial variability of CO2 uptake in polygonal tundra : Assessing low-frequency disturbances in eddy covariance flux estimates

The large spatial variability in Arctic tundra complicates the representative assessment of CO2 budgets. Accurate measurements of these heterogeneous landscapes are, however, essential to understanding their vulnerability to climate change. We surveyed a polygonal tundra lowland on Svalbard with an unmanned aerial vehicle (UAV) that mapped ice-wedge morphology to complement eddy covariance (EC) fl

Evidence for Anisotropic Electronic Coupling of Charge Transfer States in Weakly Interacting Organic Semiconductor Mixtures

We present a comprehensive investigation of the charge-transfer (CT) effect in weakly interacting organic semiconductor mixtures. The donor-acceptor pair diindenoperylene (DIP) and N,N′-bis(2-ethylhexyl)-1,7-dicyanoperylene-3,4/9,10-bis(dicarboxyimide) (PDIR-CN2) has been chosen as a model system. A wide range of experimental methods was used in order to characterize the structural, optical, elect

ENSO influence on rainy season precipitation over the Yangtze River Basin

The paper explores the impact of El Niño-Southern Oscillation (ENSO) on rainy season precipitation properties over the Yangtze River Basin. The multi-scale moving t-test was used to determine the onset and withdrawal of the rainy season. Results showed the following: (1) Onset and withdrawal of the averaged rainy season over the Yangtze River Basin showed a similar distribution and both progressed

Impedance Matching for VSC-HVDC and Energy Storage Damping Controllers

The small-disturbance electro-mechanical dynamics of a power system can be translated to an equivalent circuit model with inductances and capacitances. Damping control of active power in proportion to local frequency as with a VSC-HVDC link or an energy storage then corresponds to introducing a resistor in the circuit model. This letter shows that impedance matching can be used to select resistor

Minimization of Antenna Quality Factor

Optimal currents on arbitrarily shaped radiators with respect to the minimum quality factor are found using a simple and efficient procedure. The solution starts with a reformulation of the problem of minimizing quality factor Q as an alternative, so-called dual, problem. Taking advantage of modal decomposition and group theory, it is shown that the dual problem can easily be solved and always res

Compressed Level Crossing Sampling for Ultra-Low Power IoT Devices

Level crossing sampling (LCS) is a power-efficient analog-to-digital conversion scheme for spikelike signals that arise in many Internet of Things-enabled automotive and environmental monitoring applications. However, LCS scheme requires a dedicated time-to-digital converter with large dynamic range specifications. In this paper, we present a compressed LCS that exploits the signal sparsity in the

Constructal Optimization of Louver Fin Channels Subjected to Heat Transfer Rate Maximization and Pressure Loss Minimization

To obtain better fluid mixing and higher heat transfer rate in the low Reynolds number regime, various types of fins have been employed for electronic cooling applications. However, previous works showed that there are no remarkable differences in the thermal performance of a straight-plate and a channel with louvered-fins when the Reynolds number is low or moderate. In this paper, the Constructal

Consequences of activation policy targeting young adults with health-related problems in Sweden and Denmark

The Scandinavian countries have a long history of active labour market policy, using activation to promote work among those with no problems besides unemployment. However, activation policy is now permeating social policies providing economic protection for young adults who cannot work for health reasons, which has been legitimised through a strong emphasis on paid work as the main source of socia

Case Report : Implications of Doing Research on Socially Assistive Robots in Real Homes

The current paper addresses the implications of doing research on socially assistive robots in real homes. In contrast to laboratory studies, studies of robots in their intended natural environments can provide insights into people’s experiences of robots, and if and how a robot becomes embedded and used in people’s everyday life. However, moving robots out of the lab and into real life environmen

Top 40 questions in coupled human and natural systems (CHANS) research

Understanding and managing coupled human and natural systems (CHANS) is a central challenge of the 21st century, but more focus is needed to pursue the most important questions within this vast field given limited research capacity and funding. We present 40 important questions for CHANS research, identified through a two-part crowdsourcing exercise within the CHANS community. We solicited members

Measurements of the production cross section of a Z boson in association with jets in pp collisions at √s=13 TeV with the ATLAS detector

Measurements of the production cross section of a Z boson in association with jets in proton–proton collisions at s=13 TeV are presented, using data corresponding to an integrated luminosity of 3.16 fb- 1 collected by the ATLAS experiment at the CERN Large Hadron Collider in 2015. Inclusive and differential cross sections are measured for events containing a Z boson decaying to electrons or muons

How cube-like must magnetic nanoparticles be to modify their self-assembly?

Systems whose magnetic response can be finely tuned using control parameters, such as temperature and external magnetic field strength, are extremely desirable, functional materials. Magnetic nanoparticles, in particular suspensions thereof, offer opportunities for this controllability to be realised. Cube-like particles are particularly mono-disperse examples that, together with their favourable

The passivating effect of cadmium in PbS/CdS colloidal quantum dots probed by nm-scale depth profiling

Achieving control of the surface chemistry of colloidal quantum dots (CQDs) is essential to fully exploit their properties in solar cells, but direct measurement of the chemistry and electronic structure in the outermost atomic layers is challenging. Here we probe the surface oxidation and passivation of cation-exchanged PbS/CdS core/shell CQDs with sub nm-scale precision using synchrotron-radiati

Fe Oxides on Ag Surfaces : Structure and Reactivity

One layer thick iron oxide films are attractive from both applied and fundamental science perspectives. The structural and chemical properties of these systems can be tuned by changing the substrate, making them promising materials for heterogeneous catalysis. In the present work, we investigate the structure of FeO(111) monolayer films grown on Ag(100) and Ag(111) substrates by means of microscop

Feasibility study for the measurement of πn transition distribution amplitudes at P ANDA in p →j /ψπ0 FEASIBILITY STUDY for the MEASUREMENT of ⋯ B. SINGH et al. SINGH

The exclusive charmonium production process in pp annihilation with an associated π0 meson pp→J/ψπ0 is studied in the framework of QCD collinear factorization. The feasibility of measuring this reaction through the J/ψ→e+e- decay channel with the AntiProton ANnihilation at DArmstadt (PANDA) experiment is investigated. Simulations on signal reconstruction efficiency as well as the background reject

The new EU rules on electronic insolvency registers

This paper deals with those provisions of the new EU Regulation No. 2015/848 on Insolvency Proceedings (Recast) that create a system of national insolvency registers and establish a decentralized system for the interconnection of such registers by means of the European e-Justice Portal.

Evaluating a Dynamic Keep-Alive Messaging Strategy for Mobile Pervasive Systems

Timely loss-of-contact detection between devices in pervasive systems using mobile networks is an important aspect for both functionality and user experience. Traditional schemes where time-to-live is defined by the service provider are not adequate in mobile networks where communication failures are frequent. On the other hand, schemes using keep-alive messaging tend to increase the communication

The Role of Finance Ministries in Environmental Policy Making : The case of European Union Emissions Trading System reform in Denmark, Germany and the Netherlands

Environmental policy-making increasingly involves ministries beyond environment ministries. In particular, finance ministries are important, since they control the public budget and address environmental issues from a perspective different from environmental actors. The role of finance ministries is especially salient in the European Union's (EU) Emissions Trading System (ETS), which has been subj

The scandal of big tobacco’s behaviour in the developing world

That big tobacco hinders the adoption of anti-smoking legislation is no surprise. Your leader correctly identifies the best route to behavioural change – shareholder pressure – but does not highlight the key channel to achieve this. Big tobacco needs to diversify. This is where shareholder pressure should be applied: to encourage manufacturers and associated leaf merchants to invest in non-harmful