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A Search for Coincident Neutrino Emission from Fast Radio Bursts with Seven Years of IceCube Cascade Events
Get PDFThis paper presents the results of a search for neutrinos that are spatially and temporally coincident with 22 unique, nonrepeating fast radio bursts (FRBs) and one repeating FRB (FRB 121102). FRBs are a rapidly growing class of Galactic and extragalactic astrophysical objects that are considered a potential source of high-energy neutrinos. The IceCube Neutrino Observatory\u27s previous FRB analyses have solely used track events. This search utilizes seven years of IceCube cascade events which are statistically independent of track events. This event selection allows probing of a longer range of extended timescales due to the low background rate. No statistically significant clustering of neutrinos was observed. Upper limits are set on the time-integrated neutrino flux emitted by FRBs for a range of extended time windows
Analysis of V2X Sidelink Positioning in sub-6 GHz
No full textRadio positioning is an important part of joint communication and sensing in beyond 5G communication systems. Existing works mainly focus on the mmWave bands and under-utilize the sub-6 GHz bands, even though it is promising for accurate positioning, especially when the multipath is uncomplicated, and meaningful in several important use cases. In this paper, we analyze V2X sidelink positioning and propose a new approximate performance bound that can predict the positioning performance in the presence of severe multipath. Simulation results using ray-tracing data demonstrate the possibility of sidelink positioning, and the efficacy of the new performance bound and its relation with the complexity of the multipath
Design Developer Competitions in H\ue4rryda - From Programming to Implementation
Get PDFThis study examines three design developer competitions organized by H\ue4rryda Municipality in 2015, 2017 and 2018. The competitions aimed at new housing. The investigation of the competition processes is part of a research project developed in 2020 in collaboration with the municipality.The design developer competition is a type of competition that emerged in Sweden during the deregulation of the building sector in the 1980s. Since then, the number of these competitions has grown and is now more common in Sweden than the traditional architectural competition. However, there are still no national rules. Instead, the design developer competition is regulated locally in municipalities through political guidelines and professional competition programs.This investigation of competition processes in H\ue4rryda Municipality is based on a close reading of documents, study visits and interviews with a limited number of key players. The intention is to describe, review and comment on the planning, steering and implementation of the winning design. The research issues have a fundamental nature. They include the process from local guidelines to programming, design and judging of proposals to implementation. H\ue4rryda Municipality has a strong position in this type of competition and may safeguard qualities in architecture as organizer, landowner and planning authority by designing detailed development plans and checking building permits.The results of the study have been summarized in six conclusions that discuss the transformation of guidelines into design, planning and programming, design proposals, judging model and the organizers’ use of steering tools
Temperature and concentration dependence of the electrochemical PtHg4 alloy formation for mercury decontamination
Get PDFNew and improved methods to remove toxic mercury from contaminated waters and waste streams are highly sought after. Recently, it was shown that electrochemical alloy formation of PtHg4 on a platinum surface with mercury ions from solution can be utilized for decontamination, with several advantages over conventional techniques. Herein, we examine the alloy formation process in more detail by mercury concentration measurements using inductively coupled plasma mass spectrometry in batch measurements as well as electrochemical quartz crystal microbalance analysis both in batch and in flowing water with initial mercury concentrations ranging from 0.25 to 75000 \ub5g L−1 Hg2+. Results show that mercury is effectively removed from all solutions and the rate of alloy formation is constant over time, as well as for very thick layers of PtHg4. The apparent activation energy for the electrochemical alloy formation was determined to be 0.29 eV, with a reaction order in mercury ion concentration around 0.8. The obtained results give new insights that are vital in the assessment and further development of electrochemical alloy formation as a method for large scale mercury decontamination
A general model to predict small molecule substrates of enzymes based on machine and deep learning
Get PDFFor most proteins annotated as enzymes, it is unknown which primary and/or secondary reactions they catalyze. Experimental characterizations of potential substrates are time-consuming and costly. Machine learning predictions could provide an efficient alternative, but are hampered by a lack of information regarding enzyme non-substrates, as available training data comprises mainly positive examples. Here, we present ESP, a general machine-learning model for the prediction of enzyme-substrate pairs with an accuracy of over 91% on independent and diverse test data. ESP can be applied successfully across widely different enzymes and a broad range of metabolites included in the training data, outperforming models designed for individual, well-studied enzyme families. ESP represents enzymes through a modified transformer model, and is trained on data augmented with randomly sampled small molecules assigned as non-substrates. By facilitating easy in silico testing of potential substrates, the ESP web server may support both basic and applied science
Satellite-Based Estimation of Soil Moisture Content in Croplands: A Case Study in Golestan Province, North of Iran
Get PDFSoil moisture content (SMC) plays a critical role in soil science via its influences on agriculture, water resources management, and climate conditions. There is broad interest in finding relationships between groundwater recharge, soil characteristics, and plant properties for the quantification of SMC. The objective of this study was to assess the potential of optical satellite imagery for estimating the SMC over cropland areas. For this purpose, we collected 394 soil samples as targets in Gonbad-e Kavus in the Golestan province in the north of Iran, where a variety of crop types are cultivated. As input data, we first computed several spectral indices from Sentinel 2 (S2) and Landsat 8 (L8) images, such as the Normalized Difference Water Index (NDWI), Modified Normalized Difference Water Index (MNDWI), and Normalized Difference Salinity Index (NDSI), and then analyzed their relationships with surveyed SMC using four machine learning regression algorithms: random forests (RFs), XGBoost, extra tree decision (EDT), and support vector machine (SVM). Results revealed a high and rather similar correlation between the spectral indices and measured SMC values for both S2 and L8 data. The EDT regression algorithm yielded the highest accuracy, with an R2 = 0.82, MAE = 3.74, and RMSE = 1.08 for S2 and R2 = 0.88, RMSE = 2.42, and MAE = 1.08 for L8 images. Results also revealed that MNDWI, NDWI, and NDSI responded most sensitively to SMC estimation
Evolution of the Outflow in the Water Fountain Source IRAS 18043-2116
Get PDFWe present the spectral and spatial evolution of H2O masers associated with the water fountain source IRAS 18043-2116, found in observations with the Nobeyama 45 m Telescope and the Australia Telescope Compact Array. We have found new highest-velocity components of the H2O masers (at the redshifted side V (LSR) similar or equal to 376 km s(-1) and at the blueshifted side V (LSR) similar or equal to -165 km s(-1)), and the resulting velocity spread of similar or equal to 540 km s(-1) breaks the speed record of fast jets/outflows in this type of sources. The locations of those components have offsets from the axis joining the two major maser clusters, indicating a large opening angle of the outflow (similar to 60 degrees). The evolution of the maser cluster separation of similar to 2.9 mas yr(-1) and the compact (similar to 0.\u27\u27 2) CO emission source mapped with the Atacama Large Millimeter-submillimeter Array suggest a very short (similar to 30 yr) timescale of the outflow. We also confirmed an increase in the flux density of the 22 GHz continuum source. The properties of the jet and the continuum sources and their possible evolution in the transition to the planetary nebula phase are further discussed
Municipal facilities managers as strategists
Get PDFPurpose: This study aims to investigate practitioners’ perceptions of strategic work in municipal facilities management: how public facilities management is changing, what is included in strategic public facilities management and who leads the strategic work. Design/methodology/approach: A literature review begins with mainstream studies of strategy management, ultimately concentrating on municipal facilities management. Findings are based on a 2020/2021 questionnaire targeting 356 practitioners in municipal facilities management across Sweden (50% response rate). The statistical treatment includes factor analysis. Findings: Most respondents indicated changed ways of managing facilities in the past five years; most reported that they were in an organization with an explicit goal of working more strategically. Respondents associated strategic facilities management with governance, facilities, sustainability, technology change and communication. Frequently, it was the management team of the facilities management department that led strategic work. Research limitations/implications: Research into municipal facilities management is dominated by studies in Northern Europe, and more studies from other regions are needed. How strategies and work roles evolve in parallel appears to be a fruitful direction of further research. Practical implications: Facilities managers need stronger competences and more resources to engage in strategic facilities management. Findings indicate a need to integrate sustainability aspects better into long-term strategic work. Social implications: More strategic municipal facilities management is of obvious social value. Originality/value: This is the first study of practitioner perceptions of work on strategic facilities management in municipalities
Effects of Detuning on Wide-Temperature Behavior of 25 Gbaud 850 nm VCSELs
Get PDFEmerging markets for optical interconnects with VCSEL-based transceivers require VCSELs with superior wide temperature performance. One of the prime parameters controlling the temperature dependence of VCSEL performance is wavelength detuning. We study the impact of detuning on the performance of 25 Gbaud class 850 nm VCSELs over a temperature range of -40 to 125\ub0C, as applicable to e.g. automotive optical networking. Two VCSELs with different detuning, but otherwise identical, are compared. Basic static and dynamic performance parameters and their temperature dependencies are extracted. The results show that with appropriate detuning, sufficient performance at the temperature extremes and improved tolerance to temperature variations can be achieved. Excessive detuning to meet the more challenging high temperature performance requirements leads to insufficient low temperature performance
