A Millimeter Wave MIMO Testbed for 5G Communications

This paper presents a 2 x 2 millimeter wave (mm-wave) multiple-input-multiple-output (MIMO) testbed that operates at around 30 GHz. The link assessment of the system operating at 26.25 GHz was carried out on a test bench, with a short communication distance between the transmitting and receiving antennas. A user-programmable, reconfigurable and real-time signal processing field-programmable gate arrays (FPGAs)-based software defined radio (SDR) system was employed as part of the testbed to validate the system-level performance for a downlink time division long-term evolution (TD-LTE) duplex scheme. Constellation diagram for quadrature phase shift keying (QPSK) digital modulation were acquired while the testbed was operating at 30 GHz. The testbed could be employed for the development of signal test, communication algorithm and measurement metrology for 5G communications.Comment: 89th ARFTG Microwave Measurement Conference (ARFTG 2017

Novel methods for measuring drought stress of crops in the field

There is currently no available method for land managers to directly and non-destructively measure the water status of plants in the field. Water status of a plant effects plant growth and function and contributes to end-of-season crop yield. We have developed wearable, minimally invasive microneedle sensors that can be precisely placed in leaves of crops, to be used as electrodes for electrical impedance spectroscopy (EIS). EIS measures the passive electrical properties (magnitude and phase shift of impedance) of the leaf. EIS can be used to model biologic tissue as an electrical circuit, where ions in the intra- and extracellular fluid are describes as resistors and the cell membrane is modeled as a capacitor. Our previous work has demonstrated that the magnitude of impedance varies with water availability and can be used to monitor drought stress. In this study, we aim to further our understanding of how phase shift of impedance correlates to tissue damage caused by drought stress. Because EIS models the cell membrane as a capacitor, we predict that changes in phase angle correspond to cell membrane damage. To continue studying EIS as an indicator of plant health, data loggers with microneedle electrodes were deployed in a field of Sorghum bicolor at the New Mexico State Agricultural Science Center in Los Lunas, New Mexico. Two genotypes of S. bicolor were divided into two study groups, one receiving normal irrigation and one receiving half the irrigation. The plant-based EIS data was collected throughout the growing season. Initial results demonstrate that we can collect continuous data directly from plants in the field. Impedance signals mirror expected diurnal cycles from previous lab-based studies. Initial results indicate that phase shift of impedance changes gradually as a leaf progresses through senescence (programmed tissue aging and death) and that phase shift of impedance changes rapidly when a leaf\u27s vascular system is damaged (inhibiting the ability of the leaf to maintain hydration). These initial results indicate that microneedle EIS monitoring of phase angle of impedance may provide land managers with a method to directly monitor plants for drought damage, while distinguishing from typical plant aging

Exploring heritage through time and space : Supporting community reflection on the highland clearances

On the two hundredth anniversary of the Kildonan clearances, when people were forcibly removed from their homes, the Timespan Heritage centre has created a program of community centred work aimed at challenging pre conceptions and encouraging reflection on this important historical process. This paper explores the innovative ways in which virtual world technology has facilitated community engagement, enhanced visualisation and encouraged reflection as part of this program. An installation where users navigate through a reconstruction of pre clearance Caen township is controlled through natural gestures and presented on a 300 inch six megapixel screen. This environment allows users to experience the past in new ways. The platform has value as an effective way for an educator, artist or hobbyist to create large scale virtual environments using off the shelf hardware and open source software. The result is an exhibit that also serves as a platform for experimentation into innovative ways of community co-creation and co-curation.Postprin

Spectral State Transitions of the Ultraluminous X-ray Source IC 342 X-1

We observed the Ultraluminous X-ray Source IC 342 X-1 simultaneously in X-ray and radio with Chandra and the JVLA to investigate previously reported unresolved radio emission coincident with the ULX. The Chandra data reveal a spectrum that is much softer than observed previously and is well modelled by a thermal accretion disc spectrum. No significant radio emission above the rms noise level was observed within the region of the ULX, consistent with the interpretation as a thermal state though other states cannot be entirely ruled out with the current data. We estimate the mass of the black hole using the modelled inner disc temperature to be $30~\mathrm{M_{\odot}} \lesssim M\sqrt{\mathrm{cos}i}\lesssim200~\mathrm{M_{\odot}}$ based on a Shakura-Sunyaev disc model. Through a study of the hardness and high-energy curvature of available X-ray observations, we find that the accretion state of X-1 is not determined by luminosity alone.Comment: 10 pages, 5 Figures. MNRAS: Accepted 2014 July 2

Towards the 3D Web with Open Simulator

Continuing advances and reduced costs in computational power, graphics processors and network bandwidth have led to 3D immersive multi-user virtual worlds becoming increasingly accessible while offering an improved and engaging Quality of Experience. At the same time the functionality of the World Wide Web continues to expand alongside the computing infrastructure it runs on and pages can now routinely accommodate many forms of interactive multimedia components as standard features - streaming video for example. Inevitably there is an emerging expectation that the Web will expand further to incorporate immersive 3D environments. This is exciting because humans are well adapted to operating in 3D environments and it is challenging because existing software and skill sets are focused around competencies in 2D Web applications. Open Simulator (OpenSim) is a freely available open source tool-kit that empowers users to create and deploy their own 3D environments in the same way that anyone can create and deploy a Web site. Its characteristics can be seen as a set of references as to how the 3D Web could be instantiated. This paper describes experiments carried out with OpenSim to better understand network and system issues, and presents experience in using OpenSim to develop and deliver applications for education and cultural heritage. Evaluation is based upon observations of these applications in use and measurements of systems both in the lab and in the wild.Postprin

Evaluation of quality attributes in the freight transport market. Stated preference experiments in Switzerland

Globalization and European integration increase the claim for better quality in freight transport and logistics services. The paper focuses on the evaluation of different quality attributes of transport services in a significant segment in the Swiss freight market. The paper is based on conjoint analysis, generated by discrete binary choices between alternatives of hypothetical transport services, described by a combination of four attributes articulated on different levels. The estimated results confirm the high importance of punctuality and avoidance of damages. It could also show the statistically significant relation of the declining value of time with increasing distance

Growing the use of Virtual Worlds in education : an OpenSim perspective

The growth in the range of disciplines that Virtual Worlds support for educational purposes is evidenced by recent applications in the fields of cultural heritage, humanitarian aid, space exploration, virtual laboratories in the physical sciences, archaeology, computer science and coastal geography. This growth is due in part to the flexibility of OpenSim, the open source virtual world platform which by adopting Second Life protocols and norms has created a de facto standard for open virtual worlds that is supported by a growing number of third party open source viewers. Yet while this diversity of use-cases is impressive and Virtual Worlds for open learning are highly popular with lecturers and learners alike immersive education remains an essentially niche activity. This paper identifies functional challenges in terms of Management, Network Infrastructure, the Immersive 3D Web and Programmability that must be addressed to enable the wider adoption of Open Virtual Worlds as a routine learning technology platform. We refer to specific use-cases based on OpenSim and abstract generic requirements which should be met to enable the growth in use of Open Virtual Worlds as a mainstream educational facility. A case study of a deployment to support a formal education curriculum and associated informal learning is used to illustrate key points.Postprin

Updates on post-release mortality of shortfin mako in the Atlantic using satellite telemetry

This paper provides an update of the study on post-release mortality of the shortfin mako, Isurus oxyrinchus developed within the ICCAT Shark Research and Data Collection Program (SRDCP). Up to date, 43 tags (14 sPATs and 29 miniPATs) have been deployed by observers on Brazilian, Portuguese, Spanish, Uruguayan, and US vessels in the temperate NE and NW, Equatorial and SW Atlantic. Data from 35 out of 43 tagged specimens could be used to obtain preliminary information regarding post-release mortality, resulting in a total of 8 mortality and 27 survival events.This study was carried out as part of a cooperative work conducted by the ICCAT Shark species group integrated in the ICCAT Shark Research and Data Collection Program (SRDCP). The authors are grateful to all fishery observers and longline skippers from the Nations involved in this study. Tags from additional sources have been contributed and deployed with several national Projects, specifically: Project "LL-Sharks: Mitigação das capturas de tubarões na pescaria de palangre de superfície (Ref: 31-03-05-FEP-44, funded by PROMAR)", Project "MAKO-WIDE - "A wide scale inter-hemispheric and inter-disciplinary study aiming the conservation of the shortfin mako shark in the Atlantic Ocean (Ref: FAPESP/19740/2014)", funded by FCT (Portuguese Foundation for Science and Technology) and FAPESP (São Paulo Research Foundation, Brazil), and Project SAFEWATERS SC7 (The provision of advice on the conservation of pelagic sharks associated to fishing activity under EU Sustainable Fisheries Partnership Agreements in the Atlantic Ocean) under the Framework Contract MARE/2012/21, funded by the European Commission. Additional satellite tags were acquired by NOAA in US-Uruguay and US-Portugal-Uruguay collaboration initiatives. Rui Coelho is supported by an Investigador-FCT contract from the Portuguese Foundation for Science and Technology (FCT) supported by the EU European Social Fund and the Programa Operacional Potencial Humano (Ref: IF/00253/2014). Catarina C. Santos is supported by an FCT Doctoral grant (Ref: SFRH/BD/139187/2018).info:eu-repo/semantics/draf

OPTIMAL INVESTMENT PLANNING THROUGH BALANCING LOAD GROWTH WITH NETWORK RISK

ABSTRAC