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Among concentrating solar power technologies, direct steam generation solar tower power plants represent a promising option. These systems eliminate the usage of heat transfer fluids allowing for the power block to be run at greater operating temperatures and therefore further increasing the thermal efficiency of the power cycle. On the other hand, the current state of the art of these systems doe

This paper discusses the design and analysis of a reflector antenna system combining two doubly-curved Circular Polarization Selective Surfaces to provide a functionality equivalent to that of a dual gridded reflector but in circular polarization. The key feature of this design is to use a non-resonant CPSS design to avoid the bandwidth limitation of most CPSS designs previously discussed in the l

The latest study of the millimeter wave (mmWave) phased array in user device (UE) for 5G communication is presented in this paper. Particularly, the body effect on the phased array in a UE/mobile terminal at 15 GHz is investigated with the 3D measured data. Its impact on the recently introduced parameter for phased array in mobile terminal, the total scanning pattern, body loss and the coverage ef

A microstrip antenna integration with a power amplifier is presented for the 60 GHz band. The antenna is a single layer 4×4 square patches array. The power amplifier is injection locked, designed in a 65 nm CMOS technology, with single-ended input and output signals. The integration is realized by means of bond wire connections. The antenna and the power amplifier are fabricated, characterized and

We report the growth of InAs/GaSb core-shell heterostructure nanowires with smooth sidewalls on Si substrates using metal-organic chemical vapor deposition with no assistance from foreign catalysts. Sb adatoms were observed to strongly influence the morphology of the GaSb shell. In particular, Ga droplets form on the nanowire tips when a relatively low TMSb flow rate is used, whereas the droplets

Understanding of the electrical contact properties of semiconductor nanowire (NW) field-effect transistors (FETs) plays a crucial role in the use of semiconducting NWs as building blocks for future nanoelectronic devices and in the study of fundamental physics problems. Here, we report on a study of the contact properties of Ti/Au, a widely used contact metal combination, when contacting individua

Idag tillhör persondatorerna våra käraste prylar, men så har det inte alltid varit. Kring 1980, då persondatorerna slog igenom i Sverige, sågs "datafrågorna" istället tillhöra samhällets stora utmaningar, tillsammans med bland annat energiförsörjningen och miljöfrågorna. Dessa datafrågor debatterades häftigt, och i fackpressen kritiserades särskilt Sveriges Television för att ge en alldeles för dy

Universal Serial Bus (USB) is a new interface standard for connecting peripheral devices to personal computers. A USB system consists of a host (typically a PC) and a number of peripherals with USB interfaces.In this thesis, we have investigated an alternative approach to the PC based system. We have developed a camera server which connects a USB camera directly to Ethernet. The server is an indep

We introduce a scalable observer architecture to estimate the states of a discrete-time linear-time-invariant (LTI) system whose sensors can be manipulated by an attacker. Given the maximum number of attacked sensors, we build on previous results on necessary and sufficient conditions for state estimation, and propose a novel multi-modal Luenberger (MML) observer based on efficient Satisfiability

We have searched for the simplest kaonic nuclear state, K̄NN, using the in-flight 3He (K-, n) reaction at the J-PARC hadron experimental facility. In the semi-inclusive neutron missing-mass spectrum at θnlab=0°, an excess of yield was observed just below the K- pp mass-threshold, which cannot be explained by any elementary reactions [PTEP 2015, 061D01]. To understand the missing-mass spectrum of 3

This paper examines situations in which people restrict themselves in order to control their online searching and how this is negotiated. It is framed in a sociomaterial perspective taking account of the entanglement of information technology with its users and the conditions of its use. It contributes to a conceptual discussion of the sociomaterial shaping of the informational texture of issues a

Aim: To test if a phytoplankton bloom is panmictic, or whether geographical and environmental factors cause spatial and temporal genetic structure. Location: Baltic Sea. Method: During four cruises, we isolated clonal strains of the diatom Skeletonema marinoi from 9 to 10 stations along a 1132 km transect and analysed the genetic structure using eight microsatellites. Using F-statistics and Bayesi

This paper proposes two bootstrap-based tests that can be used to infer whether the individual slopes in a panel regression model are homogenous. The first test is suitable when wanting to infer the null of homogeneity versus the general alternative, while the second is suitable when wanting to infer the units of the panel that can be pooled. Both approaches are shown to be asymptotically valid, a