scholarly journals A linear model study of the mid-tropospheric ridge and its displacement

MAUSAM ◽  
2021 ◽  
Vol 47 (4) ◽  
pp. 369-376
Author(s):  
A. CHANDRASEKAR ◽  
B. N. GOSWAMI
Keyword(s):  
Snow Cover ◽  
Linear Model ◽  
Heat Sink ◽  
Observational Studies ◽  
Physical Mechanism ◽  
Indian Monsoon ◽  
Heat Sources ◽  
Model Study ◽  
Latitudinal Position ◽  
The Mean

 A linear model of the steady response of a stratified fluid to isolated heat sources is used to study the maintainence of the mean position of the mid-tropospheric ridge and its displacemerit. It is well known that the performance of the southwest Indian monsoon is intimately related to the latitudinal position of the April 500 hPa ridge along 75°E. Recent observational studies have demonstrated that the winter/spring snow cover over Eurasia are negatively related to the April  500 hPa ridge position. In this study we propose one possible physical mechanism of southward displacement of the mid-tropospheric ridge. The anomalous cooling associated with the increased snow cover in Eurasia may be considered as a heat sink north of  the tropical heal sources. It is demonstrated that such a heat sink can result in significant southward displacement of the mid-tropospheric ridge.  

scholarly journals A linear model study of the mid-tropospheric ridge and its displacement -inclusion of a surface heat sink

MAUSAM ◽  
2021 ◽  
Vol 48 (1) ◽  
pp. 29-32
Author(s):  
A. CHANDRASEKAR
Keyword(s):  
Snow Cover ◽  
Linear Model ◽  
Heat Sink ◽  
Observational Studies ◽  
Physical Mechanism ◽  
Stratified Fluid ◽  
Surface Heat ◽  
Heat Sources ◽  
Model Study ◽  
The Mean

ABSTRACT. A linear model of the steady response of a stratified fluid to isolated heat sources is used to study the mainlAinence of the mean position of the mid-tropospheric ridge and its displacement. There is evidence from recent observational studies that the winter/spring snow cover over Eurasia is negatively related to the April 500 hPa ridge position along 75~. In our earlier study, we proposed a possible physical mechanism of the southward displacement of the mid-tropospheric ridge. In this study the anomalous cooling associated with the increased snow cover in Eurasia is considered as a heat sink (extending to the surface), north of the tropical heat sources. It is demonstrated that such a surface heat sink can also result in significant southward displacement of the mid-tropospheric ridge.  

Analýza Kontinuálního Měření Osvětlenosti V Areálu Všb - Tu Ostrava/ Analysis of the Continual Illumination Measurement in the Area of Vsb-Technical University in Ostrava

2012 ◽  
Vol 58 (4) ◽  
pp. 28-34
Author(s):  
Zdeněk Mikulášek ◽  
Tomáš Gráf
Keyword(s):  
Statistical Analysis ◽  
Snow Cover ◽  
Linear Model ◽  
Human Activities ◽  
Moon Phases ◽  
Random Uncertainty ◽  
The Mean ◽  
Technical University ◽  
Illumination Measurement ◽  
Night Illumination

Abstract We present the results of a deep statistical analysis of the continual measurement of the mean illumination at night in the area of VSB-Technical University in Ostrava. The illumination during 509 nights between the years 2006 to 2009 was studied in detail in relation to the characteristics of a particular night. Using a sophisticated linear model applied to the logarithm of the mean night illumination, we determined the dependence of the night illumination on cloudiness, moon phases, and seasons as well as on snow cover. The model is able to predict the night illumination with quasi-random uncertainty of 0.21 dex. This uncertainty can be caused by hardly quantifiable events like rainfall, snowfall, fog or clouds with different albedo. It can also be a consequence of various human activities that may influence the illumination of sky at night

Characteristics of Tables for Disseminating Biobehavioral Results

2017 ◽  
Vol 20 (1) ◽  
pp. 70-76
Author(s):  
Barbara St. Pierre Schneider ◽  
Ed Nagelhout ◽  
Du Feng
Keyword(s):  
Linear Model ◽  
Hierarchical Linear Model ◽  
Editorial Staff ◽  
Research Articles ◽  
Biological Research ◽  
Nursing Research ◽  
Hierarchical Generalized Linear Model ◽  
Review Articles ◽  
Journal Editorial ◽  
The Mean

Background: To report the complexity and richness of study variables within biological nursing research, authors often use tables; however, the ease with which consumers understand, synthesize, evaluate, and build upon findings depends partly upon table design. Objectives: To assess and compare table characteristics within research and review articles published in Biological Research for Nursing and Nursing Research. Method: A total of 10 elements in tables from 48 biobehavioral or biological research or review articles were analyzed. To test six hypotheses, a two-level hierarchical linear model was used for each of the continuous table elements, and a two-level hierarchical generalized linear model was used for each of the categorical table elements. Additionally, the inclusion of probability values in statistical tables was examined. Results: The mean number of tables per article was 3. Tables in research articles were more likely to contain quantitative content, while tables in review articles were more likely to contain both quantitative and qualitative content. Tables in research articles had a greater number of rows, columns, and column-heading levels than tables in review articles. More than one half of statistical tables in research articles had a separate probability column or had probability values within the table, whereas approximately one fourth had probability notes. Conclusions: Authors and journal editorial staff may be generating tables that better depict biobehavioral content than those identified in specific style guidelines. However, authors and journal editorial staff may want to consider table design in terms of audience, including alternative visual displays.

scholarly journals Rotation of Galaxy Dark Matter Halos

2006 ◽  
Vol 2 (S235) ◽  
pp. 104-104
Author(s):  
Stéphane Herbert-Fort ◽  
Dennis Zaritsky ◽  
Yeun Jin Kim ◽  
Jeremy Bailin ◽  
James E. Taylor
Keyword(s):  
Dark Matter ◽  
Angular Momentum ◽  
Numerical Simulations ◽  
Galaxy Formation ◽  
Spiral Galaxy ◽  
Observational Studies ◽  
Spiral Galaxies ◽  
Satellite System ◽  
Dark Matter Halos ◽  
The Mean

AbstractThe degree to which outer dark matter halos of spiral galaxies rotate with the disk is sensitive to their accretion history and may be probed with associated satellite galaxies. We use the Steward Observatory Bok telescope to measure the sense of rotation of nearby isolated spirals and combine these data with those of their associated satellites (drawn from SDSS) to directly test predictions from numerical simulations. We aim to constrain models of galaxy formation by measuring the projected component of the halo angular momentum that is aligned with that of spiral galaxy disks, Jz. We find the mean bulk rotation of the ensemble satellite system to be co-rotating with the disk with a velocity of 22 ± 13 km/s, in general agreement with previous observational studies and suggesting that galaxy disks could be formed by halo baryons collapsing by a factor of ≈10. We also find a prograde satellite fraction of 51% and Jz, of the satellite system to be positively correlated with the disk, albeit at low significance (2655 ± 2232 kpc km/s).

scholarly journals Diurnal variability of the atmospheric boundary layer height over a tropical station in the Indian monsoon region

2017 ◽  
Vol 17 (1) ◽  
pp. 531-549 ◽  
Author(s):  
Sanjay Kumar Mehta ◽  
Madineni Venkat Ratnam ◽  
Sukumarapillai V. Sunilkumar ◽  
Daggumati Narayana Rao ◽  
Boddapaty V. Krishna Murthy
Keyword(s):  
Boundary Layer ◽  
Atmospheric Boundary Layer ◽  
Diurnal Variation ◽  
Indian Monsoon ◽  
Winter Season ◽  
Monsoon Region ◽  
Diurnal Variability ◽  
The Mean ◽  
Indian Monsoon Region ◽  
Tropical Station

Abstract. The diurnal variation of atmospheric boundary layer (ABL) height is studied using high-resolution radiosonde observations available at 3 h intervals for 3 days continuously from 34 intensive campaigns conducted during the period December 2010–March 2014 over a tropical station Gadanki (13.5° N, 79.2° E; 375 m), in the Indian monsoon region. The heights of the ABL during the different stages of its diurnal evolution, namely, the convective boundary layer (CBL), the stable boundary layer (SBL), and the residual layer (RL) are obtained to study the diurnal variabilities. A clear diurnal variation is observed in 9 campaigns out of the 34 campaigns. In 7 campaigns the SBL did not form in the entire day and in the remaining 18 campaigns the SBL formed intermittently. The SBL forms for 33–55 % of the time during nighttime and 9 and 25 % during the evening and morning hours, respectively. The mean SBL height is within 0.3 km above the surface which increases slightly just after midnight (02:00 IST) and remains almost constant until the morning. The mean CBL height is within 3.0 km above the surface, which generally increases from morning to evening. The mean RL height is within 2 km above the surface which generally decreases slowly as the night progresses. The diurnal variation of the ABL height over the Indian region is stronger during the pre-monsoon and weaker during winter season. The CBL is higher during the summer monsoon and lower during the winter season while the RL is higher during the winter season and lower during the summer season. During all the seasons, the ABL height peaks during the afternoon (∼ 14:00 IST) and remains elevated until evening (∼ 17:00 IST). The ABL suddenly collapses at 20:00 IST and increases slightly in the night. Interestingly, it is found that the low level clouds have an effect on the ABL height variability, but the deep convective clouds do not. The lifting condensation level (LCL) is generally found to occur below the ABL for the majority of the database and they are randomly related.

scholarly journals Evaluation of the reporting quality of observational studies in Master of Public Health’s dissertations in China: a systematic review

2019 ◽  
Author(s):  
ShuangYang Dai ◽  
Xiaobin Zhou ◽  
Hong Xu ◽  
Beibei Li ◽  
JinGao Zhang
Keyword(s):  
Observational Studies ◽  
Absolute Risk ◽  
Controlled Trial ◽  
Reporting Quality ◽  
Sensitivity Analyses ◽  
Flow Diagram ◽  
Master Of Public Health ◽  
The Mean ◽  
Strobe Statement

Abstract Backgrounds Master of public health (MPH) plays an important role in Chinese medical education, and the dissertations is an important part of MPH education. In MPH dissertations, most are observational studies. Compared with randomized controlled trial (RCT), observational studies are more prone to information bias. So, the reporting of the observational studies should be transparent and standard. But, no research on evaluating the reporting quality of the MPH dissertation has been found. Methods A systematic literature search was performed in the Wanfang database from January 1, 2014 to May 31, 2019. The Strengthening the Reporting of Observation Studies in Epidemiology (STROBE) statement was adopted to evaluate the reporting quality of the selected studies. Results The median of compliance with STROBE statement of 165 articles was 67.82%. The mean (standard deviation) of STROBE score was 14.3 (1.91). Five items/sub-items were 100% reported: background, objectives, study design, report numbers of individuals at each stage, and key result. Fifteen items/sub-items were reported by 75% or more. Reporting of methods and results was often omitted: missing data (12.73%), sensitivity analyses (3.03%), flow diagram (15.15%), and absolute risk (0%). Logistic regression analysis indicated that funding support (OR=13.98, 95% CI=4.37-44.70) and more published papers during postgraduate period (OR=2.77, 95% CI=1.02-7.54) were related to high reporting quality. Conclusion In short, the reporting quality of observational studies in MPH’s dissertations in China is suboptimal. However, it’s necessary to improve the reporting of method and results sections. We recommend that authors should be stricter to adhere STROBE statement when conducting observational studies.

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