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Generalized lock-in amplifiers use digital cavities with Q-factors as high as 5 × 108 to measure signals with very high precision. In this Note, we show that generalized lock-in amplifiers can be used to analyze microwave (giga-hertz) signals with a precision of few tens of hertz. We propose that the physical changes in the medium of propagation can be measured precisely by the ultra-high precisio

In this paper, we propose a directed and weighted graph model for describing P2P networks using BitTorrent protocol. Then, we analysis the topological properties of the model based on complex networks theory. We find that the node strength follows a power-law distribution and that there exists a positive correlation between flow betweenness and out-strength. We also include some other findings abo

MIMO systems ideally achieve linear capacity gain proportional to the number of antennas. However, the compactness of terminal devices limits the number of spatial degrees of freedom (DOFs) in such systems, which motivates efficientantenna design techniques to exploit all available DOFs. In this contribution, we present a compact six-port dielectric resonator antenna (DRA) array which utilizes spa

Background: Spot pricing is considered as a significant supplement for building a full-fledged market economy for the Cloud ecosystem. However, it seems that both providers and consumers are still hesitating to enter the Cloud spot market. The relevant academic community also has conflicting opinions about Cloud spot pricing in terms of revenue generation. Aim: This work aims to systematically ide

Bildstyrd strålterapi är en process bestående av att ta 2D eller 3D bilder under strålbehandlingens gång och används för att försäkra sig om att patienten är positionerad på samma sätt som referensbilden för att få samma dos som planerades (beräknat på referens bilden). I det här arbetet har en 3D scanning av patientens positionering jämförs med en CT referensbild för patienten. Efter matchen, somPurpose: The aim of this study is to a) study the benefits and limitations with soft-tissue match for lung cancer patients, b) evaluate five different soft-tissue match methods, c) compare soft-tissue with bony match, d) find the stable surrogates to match on for obscured malignant lymph nodes, e) calculate CTV to PTV and OAR margins and volume of PTV for the corresponding margins, and d) study th

Purpose: This study’s purpose is to examine if it’s possible through the Value Investing strategy The Acquirer’s Multiple to generate riskadjusted excess return during the period 2003-03-01 to 2016-03-01. Method: A study in the form of a quantitative method based on Tobias E. Carlisle formula The Acquirer’s Multiple with data extracted on a monthly basis from Thompson Reuters Datastream. Theory

The growing complexity of industrial robot work-cells calls for the use of advanced orchestration techniques to promote flexibility and reusability. This paper presents a solution based on service-oriented platforms that endorses the separation of concerns, coordination and execution. The execution is kept inside each individual device and their functionality is exposed via automatic generation of

Abstract in UndeterminedAn efficient technique is introduced to reduce mutual coupling between two closely spaced PIFAs for MIMO mobile terminals. The proposed mutual coupling reduction method is based on a T-shape slot impedance transformer and can be applied to both single-band and dual-band PIFAs. For the proposed single-band dual PIFAs, the 10 dB impedance bandwidth covers the 2.4 GHz WLAN ban

Multi-antenna enabled terminal devices are required to comply with the standards for limiting human exposure to electric fields. However, when compared to traditional single-antenna terminals, a comprehensive evaluation of specific absorption rate (SAR) for multi-antenna terminals is impractical. This is because both the power allocation and phase of the electric fields from different antennas are

We have implemented a compiler for key parts of Modelica, an object-oriented language supporting equation-based modeling and simulation of complex physical systems. The compiler is extensible, to support experiments with emerging tools for physical models. To achieve extensibility, the implementation is done declaratively in JastAdd, a metacompilation system supporting modern attribute grammar mec

TV-on-Demand services have become one of the most popular Internet applications that continuously attracts high user interest. With rapidly increasing user demands, the existing network conditions may not be able to ensure a low start-up delay of video playback. Prefetching has been broadly investigated to cope with the start-up latency problem, which is also known as user perceived latency. In th

A closely-packed ultrawideband (UWB) multiple- input multiple-output (MIMO)/diversity antenna (of two elements) with a size of 25 mm by 40 mm is proposed for USB dongle applications. Wideband isolation can be achieved through the different patterns and polarizations of the two antenna elements. Moreover, the slot that is formed between the monopole and the ground plane of the half slot antenna is

Multi-antenna design in compact mobile handsets at frequency bands below 1 GHz is very challenging, since severe mutual coupling is commonly induced by simultaneous excitation of the chassis’ fundamental dipole mode by more than one antenna element. To address this problem, a novel multi-antenna design approach is proposed herein to obtain efficient and uncorrelated antennas. By manipulating the c

In this paper, we describe an end-to-end system that automatically extracts RDF triples describing entity relations and properties from unstructured text. This system is based on a pipeline of text processing modules that includes a semantic parser and a coreference solver. By using coreference chains, we group entity actions and properties described in different sentences and convert them into en

Building big data analytics applications (BDA) in the Cloud introduces inevitable challenges such as loss of control and uncertainty. To address the existing challenges, numerous efforts have been made on BDA application engineering to optimise quality of BDA applications in the Cloud, such as performance and reliability. However, there is still a lack of systematic view on engineering BDA applica

It has been postulated that six co-located orthogonally polarized electrical and magnetic dipoles can offer up to six degrees of freedom (DOFs) in a multipath scattering environment. In other words, a six-fold increase in channel capacity can be achieved in the context of MIMO systems. However, due to the complexity in designing and measuring such a six-port antenna, to our knowledge, no experimen

This letter reports the capacity performance of a handheld dual-band dual-antenna compact MIMO terminal, which utilizes uncoupled adaptive impedance matching for capacity maximisation. The capacity is evaluated at 0.825 GHz and 2.35 GHz in an indoor office environment. The results show that adaptive matching enhances capacity by up to 44% and 22% at the low and high frequency bands, respectively,

Compact arrays such as multiple antennas on a mobile terminal suffer from low efficiency and high correlation between antenna signals. In the present paper, a simple and rigorous procedure for decoupling two closely coupled antennas with a parasitic scatterer is proposed. The parasitic scatterer, which can be an additional antenna, acts as a shield between two active antenna elements. In contrast