ABSTRACT
We present measurements of the redshift-dependent clustering of a DESI-like luminous red galaxy (LRG) sample selected from the Legacy Survey imaging data set, and use the halo occupation ...distribution (HOD) framework to fit the clustering signal. The photometric LRG sample in this study contains 2.7 million objects over the redshift range of 0.4 < z < 0.9 over 5655 deg2. We have developed new photometric redshift (photo-z) estimates using the Legacy Survey DECam and WISE photometry, with σNMAD = 0.02 precision for LRGs. We compute the projected correlation function using new methods that maximize signal-to-noise ratio while incorporating redshift uncertainties. We present a novel algorithm for dividing irregular survey geometries into equal-area patches for jackknife resampling. For a five-parameter HOD model fit using the MultiDark halo catalogue, we find that there is little evolution in HOD parameters except at the highest redshifts. The inferred large-scale structure bias is largely consistent with constant clustering amplitude over time. In an appendix, we explore limitations of Markov chain Monte Carlo fitting using stochastic likelihood estimates resulting from applying HOD methods to N-body catalogues, and present a new technique for finding best-fitting parameters in this situation. Accompanying this paper, we have released the Photometric Redshifts for the Legacy Surveys catalogue of photo-z’s obtained by applying the methods used in this work to the full Legacy Survey Data Release 8 data set. This catalogue provides accurate photometric redshifts for objects with z < 21 over more than 16 000 deg2 of sky.
Landslides during the rainy season are a usual phenomenon resulting in loss of human, animal, and property and obstructing the transportation facilities of the area. Modelling is an established tool ...for the reliable, efficient, and feasible study of landslide mechanisms. Modelling is done by simulating the material properties and boundary conditions for an existing failed slope. In the present study, an area subjected to the recurrence of landslides during the rainy season has been selected to study the mechanism that triggers landslides. After extensive fieldwork and computation of hydro-mechanical parameters through a series of laboratory experiments, a semi-similar material physical model test was conducted to study the sliding mechanism and its crucial factor. Furthermore, numerical modelling has also been done using GeoStudio to analyze the seepage and slope stability parameters to verify and compare the results to assess the suitability of this study. An artificial rainfall simulator is designed and developed to simulate the quantity and intensity of rain to study the failure mechanism and the threshold level of rainfall that causes the triggering of landslides. The physical model slope failed at 80 mm threshold rainfall depth at a 30 mm/h fixed intensity. Numerical analysis results show that the slope remains stable with a safety factor of 1.23 before the rainfall. Still, after simulating the rainfall condition for the physical model test, the slope fails at the same rainfall intensity and depth with an approximately similar failure plane with a safety factor of 0.626, indicating that rainfall is the major affecting parameter that generally initiates the landslide. This study also proves the suitability and feasibility of numerical modelling to analyze different slopes, providing scientific guidance for monitoring and early warning so that preventive measures can be taken to reduce its effect.
Landslides in northern India are a frequently occurring risk during the rainy season resulting in human, animal, and property losses as well as obstructing transportation facilities. Usually, ...numerical and analytical approaches are applied to predicting and monitoring landslides, but the unpredictable nature of rainfall-induced landslides limits these methods. Sensor-based monitoring is an accurate and reliable method, and it also collects accurate and site-specific required data for further investigation with a numerical and analytical approach. This study developed a low-cost tilt-based rainfall-induced landslide monitoring system using the economical and precise MEMS sensor to record displacement and volumetric water content. A self-developed direct shear-based testing setup was used to check the system’s operational performance. A physical slope model was also prepared to test the monitoring system in real scenarios. A debris failure occurred at Kotrupi village in the Mandi district of Himachal Pradesh, India, which was chosen for the modelling to investigate the failure mechanism. A rainfall generator was developed to simulate the rainfall, equipped with a flow sensor for better simulation and data recording. The tilt angle records the deviation in terms of angle with a least count of 0.01 degrees, and the moisture content was recorded in terms of percentage with a least count of 1. The results show that the developed system is working properly and is very effective in monitoring the rainfall-induced landslide as it monitors the gradual and sudden movement effectively. This study explains the mechanism behind the landslide, and it can be helpful in monitoring the slope to enable the implementation of preventative actions that will mitigate its impact.
Detection of volatile organic compounds (VOCs) is one of the most challenging tasks in modelling breath analyzers because of their low concentrations (parts-per-billion (ppb) to parts-per-million ...(ppm)) in breath and the high humidity levels in exhaled breaths. The refractive index is one of the crucial optical properties of metal-organic frameworks (MOFs), which is changeable via the variation of gas species and concentrations that can be utilized as gas detectors. Herein, for the first time, we used Lorentz-Lorentz, Maxwell-Ga, and Bruggeman effective medium approximation (EMA) equations to compute the percentage change in the index of refraction (Δn%) of ZIF-7, ZIF-8, ZIF-90, MIL-101(Cr) and HKUST-1 upon exposure to ethanol at various partial pressures. We also determined the enhancement factors of the mentioned MOFs to assess the storage capability of MOFs and the biosensors' selectivity through guest-host interactions, especially, at low guest concentrations.
We present results from a search for a radio transient associated with the LIGO/Virgo source S190814bv, a likely neutron star-black hole (NSBH) merger, with the Australian Square Kilometre Array ...Pathfinder. We imaged a 30 deg2 field at ΔT = 2, 9, and 33 days post-merger at a frequency of 944 MHz, comparing them to reference images from the Rapid ASKAP Continuum Survey observed 110 days prior to the event. Each epoch of our observations covers 89% of the LIGO/Virgo localization region. We conducted an untargeted search for radio transients in this field, resulting in 21 candidates. For one of these, AT2019osy, we performed multiwavelength follow-up and ultimately ruled out the association with S190814bv. All other candidates are likely unrelated variables, but we cannot conclusively rule them out. We discuss our results in the context of model predictions for radio emission from NSBH mergers and place constrains on the circum-merger density and inclination angle of the merger. This survey is simultaneously the first large-scale radio follow-up of an NSBH merger, and the most sensitive widefield radio transients search to-date.
We present the first scientific results from the luminous red galaxy (LRG) sample of the extended Baryon Oscillation Spectroscopic Survey (eBOSS) combined with the high-redshift galaxies of the ...previous BOSS sample. We measure the small- and intermediate-scale clustering from a sample of more than 97,000 galaxies in the redshift range . We interpret these measurements in the framework of the Halo Occupation Distribution. The bias of this sample of LRGs is 2.30 0.03, with a satellite fraction of 13% 3% and a mean halo mass of . These results are consistent with expectations, demonstrating that these LRGs will be reliable tracers of large-scale structure at . The galaxy bias implies a scatter of luminosity at fixed halo mass, , of 0.19 dex. Using the clustering of massive galaxies from BOSS CMASS, BOSS LOWZ, and SDSS, we find that is consistent with observations over the full redshift range that these samples cover. The addition of eBOSS to previous surveys allows the investigation of the evolution of massive galaxies over the past ∼7 Gyr.
•Reflected signal (S11) peak successfully detected EOC, ECC, & EECC damage in ADTL.•Corrosion on damaged ADTL was studied using change in magnitude & FW3QM of S11 peak.•FW3QM of S11 peak from damage ...was used to track corrosion propagation in ADTL.•Deeper damage in ADTL cause additional disturbance in the passing through signal.•S11 shape of EECC cable represent antenna signal in equally spaced reflected peaks.
Corrosion in aircraft structures and systems persists to pose significant problem in the aircraft industry. It affects both the aircraft structures and all the wiring systems including data transmission lines at the points of mechanical damage (missing or damaged insulation and jacket materials) and connections. Reliability of data transmission through aircraft data transmission lines (ATDL) is essential for maintaining performance capability and safety of flights. Unfortunately, there is no existing method for detecting corrosion and predicting its effect for wiring systems including ADTL. Detecting corrosion and predicting its effect on time would prevent unexpected system failures and catastrophes. This paper presents novel experimental method that has been employed, for the first time, to detect and study the effect of localized corrosion process on reflected and transmitted power signals passing through locally corroded ADTL with mechanically induced damage. ADTL with three types of induced damage were corroded in a Q-Fog cyclic accelerated corrosion chamber for over 14 weeks (2352 h) using ASTM G85-A5 Prohesion test that resembles the environment of aircraft operation. Cable specimens were taken out every week and investigated by measuring transmitted and reflected power signals passing through the corroded ADTL using Vector Network Analyzer (VNA), where signals from 0 to 6 GHz were swept into the ADTL. Reflected and transmitted power signals (S11 and S21 respectively) were acquired in time domain and processed in MATLAB. Analysis of results show that corrosion effect is not arbitrary and can be tracked over time and predicted. Reflected signal peak width changed over time of corrosion exposure and is proportional to corrosion propagation width inside the ADTL. It is also observed that corrosion induced extra distortion of signals passing through the corroded damage region. The results are very promising for detecting corrosion and predicting its effect in ADTL.
Tall Buildings are coming up all around the world since the land availability in the plan shape is limited hence irregular plan cross-sectional shape are designed. Wind load standards of different ...countries are also silent about the modification of tall building. The present study analysed the wind effects on the tall building where modification is provided in the vertical plane of the structure and the tall building is consisting of two types of cross-sectional shape such as square and plus shape. Wind effects are investigated from 0° to 90° wind incidence angles at the interval of the 30°. The result is presented in various graphical forms such as pressure contours stream lines in plan and average pressure coefficient on each surface of the tall building. Cross-sectional shape has a significant impact on reducing the wind effects, also it is observed that the recirculation zone of wind is most effective on one-third height of the leeward face for such type of modifications. Positive pressure was noted on the wind ward face, while suction that is negative pressure is observed on the leeward and side faces of the tall building for most of the wind incidence angle.
Introduction Difficulties with tracheal intubation contribute to the morbidity and mortality associated with anesthesia. Suggested predictors for difficult airway include, history of obstructive ...sleep apnea, high Mallampati score, elderly, male, short neck, and high Wilson score. However, none of these has high diagnostic accuracy particularly in obese population. Parameters used to quantify obesity such as Body Mass Index(BMI), mid arm circumference, skin fold thickness, etc. have not been used as independent predictors of difficult airway. This study has been designed to evaluate the accuracy of commonly used tools to assess difficult airway and to test other obesity markers as scale for assessing difficult airway i.e. Bag mask ventilation grade ≥3 or Cormack-Lehane Grade≥3 on Direct Laryngoscopy or number of intubation attempts ≥3. Aim To assess BMI, Mallampati grading, Neck circumference and Thyromental distance as predictors of difficult airway in obese patients and to validate neck circumference to thyromental distance ratio and skin fold thickness as a tool for assessment of difficult airway (Bag mask ventilation grade ≥3 or Cormack-Lehane Grade≥3 on Direct Laryngoscopy or number of intubation attempts ≥3.) in obese patients. Methods This prospective observational study was carried out on 51 obese patients (as per BMI) of ASA grade II, either sex, aged 23 to 57 years posted for elective surgery under general anesthesia with endotracheal intubation. After subjective assessment of difficult airway following data sets and variables were obtained - sex, weight, height, body mass index (BMI), Modified Mallampati class (MPG), Cormack-Lehane (CL) grade, adequacy of bag mask ventilation (BMV), number of endotracheal intubation attempts, patient's neck circumference (NC), thyromental distance (TMD), waist-hip ratio (WHR) and Skin fold thickness. The observations made during the study were statistically analyzed and correlated as predictors for difficult airway. Result Correlation of MPG to CL-grade (r-0.41, p-0.003), BMV (r-0.31, p-0.028) & No. of intubation attempts (r-0.37, p-0.007) was mild & statistically significant. Correlation of Neck Circumference with CL-grade (r-0.57, p-0.000), & No. of intubation attempts (r-0.62, p-0.000), found moderate & statistically significant, & with BMV was mild and statistically significant (r-0.48, p-0.000). Correlation of Thyromental Distance to CL-grade (r-0.65, p-0.000), BMV (r-0.70, p-0.000) & No. of intubation attempts (r-0.61, p-0.000) was moderate & statistically significant. Correlation of BMI to CL-grade (r-0.11, p-0.428), BMV (r-0.04, p-0.757) & No. of intubation attempts (r-0.16, p-0.257) was weak & not significant. Skin Fold Thickness showed no significant association with Difficult airway i.e., CL Grade (p-0.478), BMV (p-0.101), and No. of intubation attempts (p-0.143). Correlation of NC/TMD ratio with BMV (r-0.74, p-0.000), CL-grade (r-0.76, p-0.000), & No. of intubation attempts (r-0.77, p-0.000) was moderate & statistically significant. Conclusion NC, TMD and NC/TMD Ratio depicted a close association with airway difficulty in obese patients. Obesity grade is a risk factor for difficult airway but predictors of obesity including Skin Fold Thickness, individually did not show association with difficult airway (small sample size may be a limiting factor). None of the commonly performed tests alone has proven to be adequate in predicting difficult intubation in the obese population.
Background: Interns who would be the future doctors are not being observed for communication skills at their workplace. The Mini-clinical evaluation exercise (mini-CEX) can be used as a "Work Place ...Based Assessment" (WPBA) tool for the assessment of the communication skills of the interns and also for giving immediate feedback. This study was done to evaluate the acceptability, feasibility, and effectiveness of mini-CEX for improving the communication skills of interns in Pediatrics. Materials and Methods: It was a prospective interventional study which was conducted in the Department of Pediatrics. Forty interns and six faculty who volunteered participated in the mini-CEX encounters. The structured assessment mini-CEX form by the American Board of Internal Medicine was used. Each intern faced six assessment sessions on mini-CEX forms with each of the faculty. At the end of the internship rotation, the perceptions of the interns and faculty were gathered by an anonymous validated questionnaire containing both close-ended (using 5-point Likert scale) and open-ended questions. Statistical Analysis Used: The descriptive data were analyzed on the Statistical Package for the Social Sciences (SPSS) version 23. also done. Qualitative data of open-ended questions were done by thematic analysis. Results: Most interns (87.5%) and all faculty (100%) felt that mini-CEX helped them in achieving good communication skills. Comparison between the 1st and the 6th encounter of mini-CEX showed an increase in the mean score values for all skill competencies, and this improvement was statistically significant (P < 0.001). Conclusions: Mini-CEX is an acceptable, feasible, and effective WPBA tool for communication skills training of interns in pediatrics.
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