scholarly journals Milieus, Not Classes: Patterns of Horizontal Stratification in Urban Russia

2020 ◽  
Vol 21 (4) ◽  
pp. 12-29
Author(s):  
Mikhail Sokolov ◽  
Nadezhda Sokolova
2017 ◽  
Vol 51 (4) ◽  
pp. 41-51
Author(s):  
Elizabeth Ramey ◽  
Steven F. DiMarco ◽  
Karen Dreger ◽  
Heather M. Zimmerle

AbstractThe Gulf of Mexico Coastal Hypoxia Glider Experiment was designed to assess the feasibility of using ocean glider technology in the coastal hypoxic zone of the northern Gulf of Mexico in Summer/Fall 2014. The objectives were (1) to coordinate and operate multiple autonomous buoyancy ocean gliders in depths less than 50 m and (2) to determine how close to the bottom gliders can reliably reach without making contact. Strong vertical and horizontal stratification gradients, strong coastal currents, and the low-oxygen conditions that occur within the lower water column characterize the coastal area of the northern Gulf of Mexico. These environmental conditions combine with the presence of more than 5,000 surface piercing oil/gas structures to make piloting and navigation in the region challenging. We quantify glider performance to assess the usefulness of buoyancy gliders to address the National Oceanic and Atmospheric Administration Action Plan goal to monitor the spatial extent, duration, and severity of the Gulf hypoxic zone. We find that the gliders, despite the operational challenges, were consistently able to travel from the surface to the oxygen-depleted depths of subpycnocline waters, that is, within 2 m of the ocean bottom. Our assessment is that gliders are able to provide real-time observations suitable to monitor coastal hypoxia.


Geophysics ◽  
1976 ◽  
Vol 41 (3) ◽  
pp. 506-518 ◽  
Author(s):  
David L. Moffatt ◽  
R. J. Puskar

An electromagnetic pulse radar has been developed for investigation of subsurface geology and man‐made targets. The radar uses separate broadband dipole‐type antennas for transmission and reception. The antennas are well matched to the soil or rock surface. An orthogonal orientation of the antennas on the medium surface effectively decouples them and also prevents reflections from the air‐medium interface or any horizontal stratification from being seen. Two versions of the radar are used: small 6-ft dipoles with a shock‐type (250 picosec) pulse for shallow soundings and 24-ft dipoles with a 45 nanosec pulse for deeper soundings. Signatures of faults, joints, cavities, and lithologic contrasts in soft rock have been obtained with the radar, and these results are presented. A sampling oscilloscope acts as a receiver for the radar, and the target signatures are isolated portions of the time record whose time delays agree with the physical geometry and measured pulse velocities for the medium. For a large void at a depth of 20 ft in limestone, a frequency domain signature is also given to illustrate the potential of using both temporal and spectral signatures. Signatures of an exposed fault in a dolomite quarry are used via mapping measurements to delineate the direction of a minor fault. Signatures of two lithologic contrasts at depths of 40 ft in the dolomite are given. The signatures of a drift coal mine tunnel as measured from a hill 11 to 26 ft above the tunnel are shown. Unique features of the radar are enumerated and present capabilities are summarized.


2019 ◽  
Vol 5 (4) ◽  
Author(s):  
Jun Liao ◽  
Katsuhiro Ohkawa ◽  
William L. Brown ◽  
Richard F. Wright

The low-pressure depressurization system (LPDS) of advanced passive pressurized water reactors (PWRs) is designed to provide depressurization of the reactor coolant system during a small break loss-of-coolant accident (LOCA). The liquid entrainment to the LPDS is important for the safety case of the advanced passive PWRs due to the significant increase of the pressure loss and the depressurization rate versus mass loss characteristics. The existing experimental researches on the liquid entrainment at LPDS have been reviewed, and the intermittent entrainment mechanism and the continuous entrainment mechanism are identified. The intermittent entrainment is closely related to the flow regime transition from the horizontal stratified flow to the intermittent flow in the hot leg where the LPDS port is located. The horizontal stratification model previously developed for the FULL SPECTRUM LOCA evaluation model has been assessed against the entrainment onset data in the available LPDS entrainment experiments, i.e., the ATLATS air–water experiment, the ADETEL air–water and steam–water experiments, and the full-scale FATE air–water experiment. The prediction matches the measure data well especially in the full-scale FATE experiments. The comparison results also confirmed the scalability of the horizontal stratification model with the applicability of the horizontal stratification criterion to the full-scale PWR condition. The uncertainty factors that impact the depressurization system entrainment onset are discussed for the future improvements. This work provides the direction to accurately model the entrainment onset for LPDS and improve the simulation of LOCA in advanced passive PWRs.


Geophysics ◽  
1989 ◽  
Vol 54 (1) ◽  
pp. 90-99 ◽  
Author(s):  
A. M. Augustin ◽  
W. D. Kennedy ◽  
H. F. Morrison ◽  
K. H. Lee

A new electromagnetic logging method, in which the source is a horizontal loop coaxial with a cased drill hole and the secondary axial fields are measured at depth within the casing, has been analyzed. The analysis, which is for an idealized model of an infinite pipe in a conductive whole space, has shown that the casing and formation are uncoupled at the low frequencies that would be used in field studies. The field inside the casing may be found by first finding the field in the formation and then using this field as an incident field for the pipe alone. This result permits the formation response to be recovered from the measured field in the borehole by applying a correction for the known properties of the casing. If the casing response cannot be accurately predicted, a separate logging tool employing a higher frequency transmitter could be used to determine the required casing parameters in the vicinity of the receiver. This logging technique shows excellent sensitivity to changes in formation conductivity, but it is not yet known how well horizontal stratification can be resolved. One of its most promising applications will be in monitoring, through repeated measurements, changes in formation conductivity during production or enhanced recovery operations.


2010 ◽  
Vol 21 (1) ◽  
pp. 53-73 ◽  
Author(s):  
Jens Peter Thomsen

Denne artikel beskæftiger sig med social ulighed på lange videregående uddannelser i Danmark. Ved at betragte de interne forskelle i det danske universitetsfelt undersøges omfanget og karakteren af den sociale differentiering på de lange videregående uddannelser. For at forstå disse sociale differentieringsprocesser anlægges et henholdsvis makro- og mikrosociologisk perspektiv på betydningen af social klasse og kulturel praksis på uddannelserne, og der stilles det overordnede spørgsmål: Hvad er sammenhængen mellem unges valg af videregående uddannelse, deres sociale oprindelse og de kulturelle praktikker på de forskellige videregående uddannelser? Empirien udgøres af såvel registerdata som af feltarbejde på tre udvalgte universitetsuddannelser, og der bruges følgelig såvel kvantitative som kvalitative metoder. Analysen af universitetsfeltet viser at der er meget stor forskel på de forskellige uddannelsers sociale profil, at der er en tydelig klassestruktur i det danske universitetsfelt, at den kulturelle praksis der kendetegner udvalgte uddannelser kan forstås meningsfuldt i sammenhæng med denne klassestruktur, og endelig at det kræver bestemte forudsætninger at mestre kulturen på de forskellige uddannelser. Søgeord: Social differentiering, social klasse, videregående uddannelser, universitetsstuderende, uddannelseskultur, uddannelsesvalg. ENGELSK ABSTRACT: Jens Peter Thomsen: Social Class and Culture in Danish Universities In this article I address the question of social inequality in higher education. By looking at the horizontal stratification in the Danish university field I examine the extent and nature of the processes of social differentiation within the different university programs. In order to understand the processes of differentiation, a macro- and micro-sociological perspective on the significance of social class and cultural practice in the university programs is applied. The main question is: What is the relationship between young people’s choice of university program, social class origin and the cultural practices in the different university programs? National register data as well as fieldwork carried out in three different university programs make up the empirical basis of the research, and both quantitative and qualitative methods are applied. The analysis of the university field shows that: A) The university field is highly structured by social class, B) there are great differences in the class characteristics of the student body in the different programs, C) the class structure in the university field is closely related to the cultural practices characterizing specific programs, and finally, D) that students from certain social backgrounds are better prepared than other students for the practical mastery of these cultural practices. Key words: Higher education, social class, horizontal stratification, university students, educational cultures, choice of higher education.


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