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This paper discusses the change of the natural frequencies and the corresponding mode shapes of an isotropic metallic curved panel subjected to combined internal pressure and axial compression. Tensor calculus is employed to devise the differential operator matrices of the geometrical relation in an orthogonal curvilinear reference system. In the framework of the Carrera unified formulation and by applying the finite element method, the principle of virtual work is used to describe the free vibration of a cylindrical shell subjected to progressive external loading conditions as a virtual procedure of the experimental test vibration correlation technique. Finally, numerical examples are provided, and the effects of the material and geometric characteristics are evaluated. The results show that crossing and veering phenomena between natural frequencies appear when varying the curvature of the panel and the value of the inner pressure, and those effects have to be taken into account for a proper design of this type of structure.

Weight loss was supposed to help with decreasing risk of premature mortality. However, results on this topic remain debatable and limited by study design.The present study aimed to investigate the association between weight loss and all-cause mortality among US adults with overweight or obesity in a national cohort study by using propensity score matching (PSM) analysis.A total of 5486 pairs of participants were matched in the National Health and Nutrition Examination Survey (NHANES, 2003-2015) after PSM. Hazard ratios (95% confidence intervals) (HRs (95% CIs)) were employed to evaluate the association between weight loss indicated by long-term weight loss (LTWL) and all-cause mortality by using Cox proportional hazards regression models.During a median follow-up of 6.8 years, 674 participants died from all-cause mortality. In each PSM match, compared with participants with LTWL 5%, the HRs (95% CIs) for participants with LTWL of 5-9.9% (2877 pairs), 10-14.9% (1315 pairs), and ≥ 15% (1294 pairs) were 1.18 (0.83-1.68) (P = 0.366), 1.65 (1.17-2.34) (P = 0.005), and 1.91 (1.21-3.00) (P = 0.006), respectively. The significant increased risk of all-cause mortality for LTWL ≥ 15% remained among male, female, participants aged ≥ 65 years, without weight loss intention, with non-communicable diseases, and without exceeding estimated energy requirement.Weight loss especially for being ≥ 15% should be cautious for US adults with overweight or obesity.

The widespread application of wireless communication technology brings great convenience to people, but security and privacy problems also arise. To assess and guarantee the security of wireless networks and user devices, discovering and identifying wireless devices become a foremost task. Currently, effective device identification is still a challenging issue, as device fingerprinting requires huge training datasets and is difficult to expand, and rule-based identification is not accurate and reliable enough. In this paper, we propose WND-Identifier, a universal and extensible framework for the identification of wireless devices, which can generate high-precision device labels (vendor, type, and product model) efficiently without user interaction. We first introduce the concept of device-info-related network protocols. WND-Identifier makes full use of the natural language features in such protocol messages and combines with the device description in the welcome page, thereby utilizing extraction rules to generate concrete device labels. Considering that the device information in the protocol messages may be incomplete or forged, we further take advantage of the application logic independence and stability of the device-info-related protocol, so as to build a multiprotocol text classification model, which maps the device to a known label. We conduct experiments in homes and public networks and present three application scenarios to verify the effectiveness of WND-Identifier.

We aimed to investigate the relationship between overall nutritional status and cancer mortality. A total of 12 262 US adults from six consecutive surveys of the National Health and Nutrition Examination Survey (NHANES 2003–2014) were analyzed. The overall health nutritional biomarkers index (HNBI) score, capturing characteristics of 17 biomarkers was developed to assess the overall nutritional status. The lower the HNBI score, the healthier nutritional status would be. Hazard ratio (HR) and 95% confidence intervals (95% CIs) were calculated by Cox proportional hazards regression models to evaluate the association between the HNBI score and cancer mortality. The lower overall HNBI score was associated with decreased risk of cancer mortality, compared with participants in the 4th quartile of overall HNBI score, the HR (95% CIs) for participants in the 1st quartiles was 0.54 (0.33–0.89) (P-trend = 0.019). Healthier lifestyle habits and not obesity interacted with HNBI score, compared with participants with higher HNBI score and smoking currently/not exercising regularly/obesity, participants with lower HNBI score and not smoking currently/exercising regularly/not obesity were associated with lower risk of cancer mortality, the HR (95% CIs) were 0.43 (0.26–0.73), 0.57 (0.33–0.97), and 0.62 (0.47–0.97), respectively. These significant associations remained among participants who were followed-up more than 2 years. Our findings suggested that healthier overall nutritional status was associated with lower risk of cancer mortality among US adults. Not smoking, exercise regularly and not obesity interacted with overall nutritional status. Adherence to better overall nutritional status, lifestyle habits and optimal weight would prevent premature death from cancer.

The proliferation of telco networks and mobile terminals brings the accumulation of tremendous amounts of measure report(MR) data at a rapid pace. The MR data is generated by mobile objects while connecting to data services and is stored in backend data centers. To geo-tag or localize such MR data is believed to have a profound effect on the analytics and optimizations of telco and traffic networks. However, MR records are of noisy and partial observations regarding to mobile objects’ geo-locations and hence pose challenges to accurate telco data localization. There have been quite a few attempts. Single-point localization methods map a MR record to a location, but come out with limited accuracies due to the ignorance of spatiotemporal coherence of successive MR records. Recent efforts on sequential localization techniques alleviate this by mapping a sequence of MR records to a trajectory. However, existing solutions are often with assumptions on specific models, e.g., mobility and signal strength distributions, or priori knowledge on topology space, e.g., road networks, limiting the deployment in practice. To this end, we propose a data-driven framework to tackle the challenges in sequential telco localization. We solely use raw MR records and a public third-party GPS dataset for the learning of the correlations between mobile objects’ locations and MR records, requiring no model assumptions and priori knowledge. To handle the data-intensive workloads during the learning process, we use materialized views for efficient online localization and light-weighted indexing techniques for periodical parameters tuning, in order to improve the efficiency and scalability. Results on real data show that our solution achieves 58.8 percent improvement in median localization errors compared with state-of-art sequential localization techniques that require hypothesis models and priori knowledge, making our solution superior in terms of effectiveness, efficiency, and employability.

The security of wireless routers receives much attention given by the increasing security threats. In the era of Internet of Things, many devices pose security vulnerabilities, and there is a significant need to analyze the current security status of devices. In this paper, we develop WNV-Detector, a universal and scalable framework for detecting wireless network vulnerabilities. Based on semantic analysis and named entities recognition, we design rules for automatic device identification of wireless access points and routers. The rules are automatically generated based on the information extracted from the admin webpages, and can be updated with a semi-automated method. To detect the security status of devices, WNV-Detector aims to extract the critical identity information and retrieve known vulnerabilities. In the evaluation, we collect information through web crawlers and build a comprehensive vulnerability database. We also build a prototype system based on WNV-Detector and evaluate it with routers from various vendors on the market. Our results indicate that the effectiveness of our WNV-Detector, i.e., the success rate of vulnerability detection could achieve 95.5%.

Although plasma, especially atmospheric plasma generated by corona discharge, has been proven to be effective in sterilization and food preservation, its disinfection mechanism on chilled pork is poorly understood. In this research, the bactericidal and preservation effect of corona discharge plasma (CDP) was investigated. The maximum bactericidal effect was found after 20 kV 4 kHz CDP treatment, with 2.77 log (colony-forming unit [CFU]/g), 2.41 log (CFU/g), and 1.36 log (CFU/g) reduction for

The COVID-19 pandemic continues to pose challenges to the teaching and learning of English as a foreign language (EFL) around the globe, including China. Through online instruction, data-driven learning (DDL), a pedagogical tool that extracts concordances of authentic language examples from specific corpora, can be seen as a powerful resource for helping learners deal with their EFL writing errors during the lockdown. This paper examines the effects of DDL on students’ EFL writing accuracy considering four specific error types and shows how students, as well as teachers, perceive this learning method. Four students and their English teacher in a Chinese university participated in this study. Students were required to complete six writing tasks electronically, which were later revised for four most frequent lexico-grammatical errors under the conditions of using (a) typical referencing resources, (b) DDL material only and (c) the combination of two. Online error correction spreadsheets and stimulated recall were used to investigate students’ error correction preferences and processes, while the online questionnaire and interview were used to retrieve students’ and their teacher’s perceptions of DDL-mediated error correction. The qualitative data analysis revealed that DDL material supported activation of students’ prior knowledge and helped them learn appropriate language use by utilising a series of cognitive strategies. Participants highly appreciated the advantages of DDL-mediated writing activities, although some reservations were made about their practices which warrant further investigation.

Background: Understanding trend in nutritional status is crucial to inform national health priorities to improve diets and reduce related diseases. The present study aimed to analyze trends in the concentrations of all measured nutritional biomarkers and their status among US adults across 14 years.Methods: Trends on the concentrations of nutritional biomarkers and nutritional status evaluated by the prevalence of deficiency, inadequacy, excess, and dyslipidemia were analyzed among US adults in 7 cross-sectional National Health and Nutrition Examination Surveys (NHANES 2003–2016) and by age, sex, race/ethnicity, and socioeconomic status.Results: A total of 38,505 participants (weighted mean age of 47.2 years, 51.4% women) were included in the present study. Across 14 years, increased trends were found in red blood cell (RBC) folate, serum vitamin B12, vitamin D and albumin, the prevalence of iodine deficiency, vitamin B6 inadequacy, and hypophosphatemia, whereas decreased trends were observed in serum vitamin E, phosphorus, total calcium, total protein, apolipoprotein B (Apo B), low-density-lipoprotein cholesterol (LDL-C), triglyceride (TG), total cholesterol (TC), blood lead, cadmium, mercury, and the prevalence of vitamin C deficiency, vitamin D inadequacy, iodine excess, and dyslipidemia with elevated LDL-C, TC, TG, and lowered HDL/LDL. Non-Hispanic blacks (NHB) and participants with low socioeconomic status were accounted for the poor nutritional status of most biomarkers compared to their comparts.Conclusion: Most nutritional biomarkers and their status were improved among US adults from 2003 to 2016, but some specific populations should be paid much attention to improve their nutritional status, especially for NHB and participants with low socioeconomic status.

The security of wireless network devices has received widespread attention, but most existing schemes cannot achieve fine-grained device identification. In practice, the security vulnerabilities of a device are heavily depending on its model and firmware version. Motivated by this issue, we propose a universal, extensible and device-independent framework called SCAFFISD, which can provide fine-grained identification of wireless routers. It can generate access rules to extract effective information from the router admin page automatically and perform quick scans for known device vulnerabilities. Meanwhile, SCAFFISD can identify rogue access points (APs) in combination with existing detection methods, with the purpose of performing a comprehensive security assessment of wireless networks. We implement the prototype of SCAFFISD and verify its effectiveness through security scans of actual products.

Due to their unique electromechanical coupling properties, soft electro-active (SEA) resonators are actively tunable, extremely suitable, and practically important for designing the next-generation acoustic and vibration treatment devices. In this paper, we investigate the electrostatically tunable axisymmetric vibrations of SEA tubes with different geometric sizes. We consider both axisymmetric torsional and longitudinal vibrations for an incompressible SEA cylindrical tube under inhomogeneous biasing fields induced by radial electric voltage and axial pre-stretch. We then employ the state-space method, which combines the state-space formalism in cylindrical coordinates with the approximate laminate technique, to derive the frequency equations for two separate classes of axisymmetric vibration of the tube subjected to appropriate boundary conditions. We perform numerical calculations to validate the convergence and accuracy of the state-space method and to illuminate that the axisymmetric vibration characteristics of SEA tubes may be tuned significantly by adjusting the electromechanical biasing fields as well as altering the tube geometry. The reported results provide a solid guidance for the proper design of tunable resonant devices composed of SEA tubes. (c) 2020 Elsevier Ltd. All rights reserved. This work was supported by a Government of Ireland Postdoctoral Fellowship from the Irish Research Council (No. GOIPD/2019/65) and the National Natural Science Foundation of China (Nos. 11872329 and 11621062). Partial supports from the Fundamental Research Funds for the Central Universities, PR China (No. 2016XZZX001-05) and the Shenzhen Scientific and Technological Fund for R&D, PR China (No. JCYJ20170816172316775) are also acknowledged. peer-reviewed

Phosphorous diffusion gettering (PDG) for different kinds of commercial n-type CZ silicon wafers was investigated for the application in silicon heterojunction (SHJ) solar cells. It was found that surplus phosphorus diffusion was effective in improving the effective minority carrier lifetime ( τ eff ). Highest τ eff was obtained at the optimal diffusion temperature of 840 °C, which was almost independent on the diffusion duration at a wide region from 5 to 60 min, corresponding to a sheet resistance region from 85 to 21 Ω/sq. The segregation coefficient and gettering sites were considered responsible for the gettering mechanism. When the optimized PDG process was applied to SHJ solar cells with three different groups of commercial Si wafers, the average efficiencies were improved from 21.2% to 22.4%, 21.5% to 22.4%, and 22.1% to 22.5%, respectively, where the efficiency gains were mainly contributed by the improvements of open-circuit voltage and fill factor.

The extended Baryon Oscillation Spectroscopic Survey (eBOSS) is one of the first of a new generation of galaxy redshift surveys that will cover a large range in redshift with sufficient resolution to measure the baryon acoustic oscillations (BAO) signal. For surveys covering a large redshift range we can no longer ignore cosmological evolution, meaning that either the redshift shells analysed have to be significantly narrower than the survey, or we have to allow for the averaging over evolving quantities. Both of these have the potential to remove signal: analysing small volumes increases the size of the Fourier window function, reducing the large-scale information, while averaging over evolving quantities can, if not performed carefully, remove differential information. It will be important to measure cosmological evolution from these surveys to explore and discriminate between models. We apply a method to optimally extract this differential information to mock catalogues designed to mimic the eBOSS quasar sample. By applying a set of weights to extract redshift space distortion measurements as a function of redshift, we demonstrate an analysis that does not invoke the problems discussed above. We show that our estimator gives unbiased constraints., Comment: 11 pages, 8 figures

We develop a new method, which is based on the optimal redshift weighting scheme, to extract the maximal tomographic information of baryonic acoustic oscillations (BAO) and redshift space distortions (RSD) from the extended Baryon Oscillation Spectroscopic Survey (eBOSS) Data Release 14 quasar (DR14Q) survey. We validate our method using the EZ mocks, and apply our pipeline to the eBOSS DR14Q sample in the redshift range of $0.8, Comment: 18 pages, 18 figures, 5 tables; This paper is part of a set that analyses the eBOSS DR14 quasar sample; MNRAS accepted

Large redshift surveys capable of measuring the Baryon Acoustic Oscillation (BAO) signal have proven to be an effective way of measuring the distance-redshift relation in cosmology. Building off the work in Zhu et al. (2015), we develop a technique to directly constrain the distance-redshift relation from BAO measurements without splitting the sample into redshift bins. We parametrize the distance-redshift relation, relative to a fiducial model, as a quadratic expansion. We measure its coefficients and reconstruct the distance-redshift relation from the expansion. We apply the redshift weighting technique in Zhu et al. (2015) to the clustering of galaxies from 1000 QuickPM (QPM) mock simulations after reconstruction and achieve a 0.75% measurement of the angular diameter distance $D_A$ at $z=0.64$ and the same precision for Hubble parameter H at $z=0.29$. These QPM mock catalogs are designed to mimic the clustering and noise level of the Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 12 (DR12). We compress the correlation functions in the redshift direction onto a set of weighted correlation functions. These estimators give unbiased $D_A$ and $H$ measurements at all redshifts within the range of the combined sample. We demonstrate the effectiveness of redshift weighting in improving the distance and Hubble parameter estimates. Instead of measuring at a single 'effective' redshift as in traditional analyses, we report our $D_A$ and $H$ measurements at all redshifts. The measured fractional error of $D_A$ ranges from 1.53% at $z=0.2$ to 0.75% at $z=0.64$. The fractional error of $H$ ranges from 0.75% at $z=0.29$ to 2.45% at $z = 0.7$. Our measurements are consistent with a Fisher forecast to within 10% to 20% depending on the pivot redshift. We further show the results are robust against the choice of fiducial cosmologies, galaxy bias models, and RSD streaming parameters., Comment: 13 pages, 8 figures, submitted to MNRAS

In order to obtain better performance such as low pressure and high adsorbent utilization in gas-solid fluidized bed reactor, a novel fluidized beds reactor (FBsR) is proposed in this article. The particle volume fraction, gas velocity and pressure distribution in the FBsR were calculated by the numerical method. The results show that the novel design of FBsR can get a large inlet area which enables low inlet velocity in every fluidized bed, thus yielding a low pressure in every fluidized bed of the FBsR. Furthermore, the FBsR can get high adsorption efficiency and low cost for frequently replacing the adsorbents due to full gas-solid contact and slight collisions between the adsorbents in every fluidized bed of the FBsR.

We present an anisotropic analysis of Baryon Acoustic Oscillation (BAO) signal from the SDSS-IV extended Baryon Oscillation Spectroscopic Survey (eBOSS) Data Release 14 (DR14) quasar sample. The sample consists of 147,000 quasars distributed over a redshift range of $0.8 < z < 2.2$. We apply the redshift weights technique to the clustering of quasars in this sample and achieve a 4.6 per cent measurement of the angular distance measurement $D_M$ at $z = 2.2$ and Hubble parameter $H$ at $z=0.8$. We parameterize the distance-redshift relation, relative to a fiducial model, as a quadratic expansion. The coefficients of this expansion are used to reconstruct the distance-redshift relation and obtain distance and Hubble parameter measurements at all redshifts within the redshift range of the sample. Reporting the result at two characteristic redshifts, we determine $D_M(z=1) = 3405\pm305 \ (r_{\rm d} / r_{\rm d, fid}) \ {\rm Mpc}$, $H(z=1) = 120.7\pm 7.3 \ (r_{\rm d,fid} / r_{\rm d}) \ {\rm km} \ {\rm s}^{-1}{\rm Mpc}^{-1}$ and $D_M(z=2) = 5325\pm249 \ (r_{\rm d} / r_{\rm d, fid}) \ {\rm Mpc}$, $H(z=2) = 189.9\pm 32.9 \ (r_{\rm d,fid} / r_{\rm d}) \ {\rm km} \ {\rm s}^{-1}{\rm Mpc}^{-1}$. These measurements are highly correlated. We assess the outlook of BAO analysis from the final quasar sample by testing the method on a set of mocks that mimic the noise level in the final sample. We demonstrate on these mocks that redshift weighting shrinks the measurement error by over 25 per cent on average. We conclude redshift weighting can bring us closer to the cosmological goal of the final quasar sample., 10 pages, 6 figures

We measure the growth rate and its evolution using the anisotropic clustering of the extended Baryon Oscillation Spectroscopic Survey (eBOSS) Data Release 14 (DR14) quasar sample, which includes $148\,659$ quasars covering the wide redshift range of $0.8 < z < 2.2$ and a sky area of $2112.90$ $\rm deg^2$. To optimise measurements we deploy a redshift-dependent weighting scheme, which allows us to avoid binning, and perform the data analysis consistently including the redshift evolution across the sample. We perform the analysis in Fourier space, and use the redshift evolving power spectrum multipoles to measure the redshift space distortion parameter $f\sigma_8$ and parameters controlling the anisotropic projection of the cosmological perturbations. We measure $f \sigma_8(z=1.52)=0.43 \pm 0.05 $ and $df\sigma_8/dz (z=1.52)= - 0.16 \pm 0.08$, consistent with the expectation for a $\Lambda$CDM cosmology as constrained by the Planck experiment., Comment: 11 pages

We present measurements of the Baryon Acoustic Oscillation (BAO) scale in redshift-space using the clustering of quasars. We consider a sample of 147 000 quasars from the extended Baryon Oscillation Spectroscopic Survey (eBOSS) distributed over 2044 square degrees with redshifts 0.8 < z < 2.2 and measure their spherically averaged clustering in both configuration and Fourier space. Our observational data set and the 1400 simulated realizations of the data set allow us to detect a preference for BAO that is greater than 2.8σ. We determine the spherically averaged BAO distance to z = 1.52 to 3.8 per cent precision: D (z = 1.52) = 3843 ± 147 (r/r) Mpc. This is the first time the location of the BAO feature has been measured between redshifts 1 and 2. Our result is fully consistent with the prediction obtained by extrapolating the Planck flatΛCDMbest-fitting cosmology. All of our results are consistent with basic large-scale structure (LSS) theory, confirming quasars to be a reliable tracer of LSS, and provide a starting point for numerous cosmological tests to be performed with eBOSS quasar samples. We combine our result with previous, independent, BAO distance measurements to construct an updated BAO distance-ladder. Using these BAO data alone and marginalizing over the length of the standard ruler, we find Ω > 0 at 6.6s significance when testing a ΛCDM model with free curvature.C 2017 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society, AJR is grateful for support from the Ohio State University Center for Cosmology and ParticlePhysics. HGM acknowledges support from the Labex ILP (reference ANR-10-LABX-63) part of the Idex SUPER, and received financial state aid managed by the Agence Nationale de la Recherche, as part of the programme Investissements d'avenir under the reference ANR-11-IDEX-0004-02. GBZ is supported by NSFC Grant No. 11673025, and by a Royal Society Newton Advanced Fellowship. RT acknowledges support from the Science and Technology Facilities Council via an Ernest Rutherford Fellowship (grant number ST/K004719/1) CHC is grateful for support from Leibniz-Institut fur Astrophysik Potsdam (AIP). EB and PZ acknowledge support from the P2IO LabEx (ANR-10-LABX-0038). JLT acknowledges support from National Science Foundation grant AST-1615997. YW is supported by the NSFC grant number 11403034. WJP acknowledges support from the UK Space Agency through grant ST/K00283X/1, and WJP acknowledges support from the European Research Council through grant Darksurvey, and the UK Science & Technology Facilities Council through the consolidated grant ST/K0090X/1. ADM was partially supported by the NSF through grant numbers 1515404 and 1616168. IP acknowledges the support of the OCEVU Labex (ANR-11-LABX-0060) and the A*MIDEX project (ANR-11-IDEX-0001-02) funded by the 'Investissements d'Avenir French government program managed by the AN. JPK acknowledges support from the ERC advanced grant LIDA. GR acknowledges support from the National Research Foundation of Korea (NRF) through NRF-SGER 2014055950 funded by the Korean Ministry of Education, Science and Technology (MoEST), and from the faculty research fund of Sejong University in 2016. Funding for SDSS-III and SDSS-IV has been provided by the Alfred P. Sloan Foundation and Participating Institutions. Additional funding for SDSS-III comes from the National Science Foundation and the U.S. Department of Energy Office of Science. Further information about both projects is available at www.sdss.org. SDSS is managed by the Astrophysical Research Consortium for the Participating Institutions in both collaborations. In SDSS-III, these include the University of Arizona, the Brazilian Participation Group, Brookhaven National Laboratory, Carnegie Mellon University, University of Florida, the French Participation Group, the German Participation Group, Harvard University, the Instituto de Astrofisica de Canarias, the Michigan State/Notre Dame/JINA Participation Group, Johns Hopkins University, Lawrence Berkeley National Laboratory, Max Planck Institute for Astrophysics, Max Planck Institute for Extraterrestrial Physics, New Mexico State University, New York University, Ohio State University, Pennsylvania State University, University of Portsmouth, Princeton University, the Spanish Participation Group, University of Tokyo, University of Utah, Vanderbilt University, University of Virginia, University of Washington, and Yale University. The Participating Institutions in SDSS-IV are Carnegie Mellon University, Colorado University, Boulder, Harvard-Smithsonian Center for Astrophysics Participation Group, Johns Hopkins University, Kavli Institute for the Physics and Mathematics of the Universe Max-Planck-Institut fuer Astrophysik (MPA Garching), Max-Planck-Institut fuer Extraterrestrische Physik (MPE), Max-Planck-Institut fuer Astronomie (MPIA Heidelberg), National Astronomical Observatories of China, New Mexico State University, New York University, The Ohio State University, Penn State University, Shanghai Astronomical Observatory, United Kingdom Participation Group, University of Portsmouth, University of Utah, University of Wisconsin and Yale University. This work made use of the facilities and staff of the UK Sciama High Performance Computing cluster supported by the ICG, SEP-Net and the University of Portsmouth. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.

We present a measurement of the anisotropic and isotropic Baryon Acoustic Oscillations (BAO) from the extended Baryon Oscillation Spectroscopic Survey Data Release 14 quasar sample with optimal redshift weights. Applying the redshift weights improves the constraint on the BAO dilation parameter $\alpha(z_{\rm eff})$ by 17\%. We reconstruct the evolution history of the BAO distance indicators in the redshift range of $0.8, Comment: 8 pages, 6 figures, 3 tables; This paper is part of a set that analyses the eBOSS DR14 quasar sample; MNRAS submitted

When a mobile device connects to a telecom network (e.g., GSM 2G, CDMA 3G and LTE 4G), the network generates measurement report (MR) data containing signal conditions to support communication services. Using MR data to predict the accurate position of a mobile device is an important problem in Telco industry, called Telco localization problem. Although the literatures have proposed various MR-based localization algorithms, it is unclear how such algorithms perform in terms of localization precision. We develop a tool named STLT, which supports comprehensive performance study of a broad category of the state-of-art localization algorithms. STLT provides flexible training/testing data division, deep parameter turning as well as three visualization modes to display localization results. Through the demonstration of STLT on three real MR datasets provided by one of the largest Telco operators in China, we have three interesting findings that could inspire and enhance future research in Telco location.

The low statistical errors on cosmological parameters promised by future galaxy surveys will only be realised with the development of new, fast, analysis methods that reduce potential systematic problems to low levels. We present an efficient method for measuring the evolution of the growth of structure using Redshift Space Distortions (RSD), that removes the need to make measurements in redshift shells. We provide sets of galaxy-weights that cover a wide range in redshift, but are optimised to provide differential information about cosmological evolution. These are derived to optimally measure the coefficients of a parameterisation of the redshift-dependent matter density, which provides a framework to measure deviations from the concordance $\Lambda$CDM cosmology, allowing for deviations in both geometric and/or growth. We test the robustness of the weights by comparing with alternative schemes and investigate the impact of galaxy bias. We extend the results to measure the combined anisotropic Baryon Acoustic Oscillation (BAO) and RSD signals., Comment: 10 pages, 5 figures, submitted to MNRAS

We perform a tomographic baryon acoustic oscillations (BAO) analysis using the monopole, quadrupole and hexadecapole of the redshift-space galaxy power spectrum measured from the pre-reconstructed combined galaxy sample of the completed Sloan Digital Sky Survey (SDSS-III) Baryon Oscillation Spectroscopic Survey (BOSS) Data Release (DR)12 covering the redshift range of $0.20, Comment: 20 pages, 22 figures; version accepted by MNRAS; This paper is part of a set that analyses the final galaxy clustering dataset from BOSS; The BAO measurements including the full covariance matrices presented in this work and a CosmoMC patch to use this measurement for cosmology is available at https://sdss3.org//science/boss_publications.php

It is still challenging in telecommunication (telco) industry to accurately locate mobile devices (MDs) at city-scale using the measurement report (MR) data, which measure parameters of radio signal strengths when MDs connect with base stations (BSs) in telco networks for making/receiving calls or mobile broadband (MBB) services. In this paper, we find that the widely-used location based services (LBSs) have accumulated lots of over-the-top (OTT) global positioning system (GPS) data in telco networks, which can be automatically used as training labels for learning accurate MR-based positioning systems. Benefiting from these telco big data, we deploy a context-aware coarse-to-fine regression (CCR) model in Spark/Hadoop-based telco big data platform for city-scale localization of MDs with two novel contributions. First, we design map-matching and interpolation algorithms to encode contextual information of road networks. Second, we build a two-layer regression model to capture coarse-to-fine contextual features in a short time window for improved localization performance. In our experiments, we collect 108 GPS-associated MR records in the centroid of Shanghai city with 12 x 11 square kilometers for 30 days, and measure four important properties of real-world MR data related to localization errors: stability, sensitivity, uncertainty and missing values. The proposed CCR works well under different properties of MR data and achieves a mean error of 110m and a median error of $80m$, outperforming the state-of-art range-based and fingerprinting localization methods.

We perform a tomographic baryon acoustic oscillations analysis using the two-point galaxy correlation function measured from the combined sample of BOSS DR12, which covers the redshift range of $0.2, Comment: 14 pages, 21 figures, 7 Tables. Submitted to MNRAS

We present a science forecast for the eBOSS survey, part of the SDSS-IV project, which is a spectroscopic survey using multiple tracers of large-scale structure, including luminous red galaxies (LRGs), emission line galaxies (ELGs) and quasars (both as a direct probe of structure and through the Ly-$\alpha$ forest). Focusing on discrete tracers, we forecast the expected accuracy of the baryonic acoustic oscillation (BAO), the redshift-space distortion (RSD) measurements, the $f_{\rm NL}$ parameter quantifying the primordial non-Gaussianity, the dark energy and modified gravity parameters. We also use the line-of-sight clustering in the Ly-$\alpha$ forest to constrain the total neutrino mass. We find that eBOSS LRGs ($0.60.6$), ELGs ($0.6, Comment: 15 pages, 9 figures, 6 tables; matches the published version on MNRAS