A probabilistic description of pressure ridge width, spacing, and keel depth for the Chukchi and Beaufort seas based on IPS and ADCP observations

2021 ◽  
Vol 182 ◽  
pp. 103171
Author(s):  
Vincent Valenti ◽  
Andy Mahoney ◽  
Andrew Metzger
Author(s):  
Viacheslav Karmalita

This paper confirms the principal possibility of using synergetics in macroeconomic studies. It noted that the presence in economic systems of all science typologies requires using subjects of natural and engineering sciences for the study of economic objects as well. Ignoring this fact hinders the development of fundamental economic knowledge and, as consequence, conditions the use of metaphysical concepts in developed models. Since the above interdisciplinarity is inherent in synergetics, its applicability in macroeconomics is considered. On the example of modeling economic systems, it is demonstrated that their essence (nonlinear space-time structure) corresponds to the basic provisions of synergetics. Therefore, its tools are eligible in the tasks of macroeconomic analysis. As an example, this paper proposes the stochastic model of economic cycles explaining their phenomenon as well as providing the quantitative (parametric) description of cycles. Novelty of the model describing the cycles as random oscillations is tied to the probabilistic description of the investment function and the perception of the economic system as a material object with certain inherent properties. According to a proposed model, the income oscillations are induced by both exogenous (investment fluctuations) and endogenous (economic system elasticity) causes. The values of fluctuations of the income function around its longterm trend relate to the value of intensity of investment fluctuations as well as the gain (efficiency) of the economic system. The duration of the cycle is related to the inclusive wealth of the system and its dynamic factor, which characterizes the system’s ability to withstand investment fluctuations as well as to eliminate their consequences. Prospects of practical applications of the considered model were demonstrated on the example of cycle management.


Author(s):  
Riccardo Zese ◽  
Elena Bellodi ◽  
Evelina Lamma ◽  
Fabrizio Riguzzi ◽  
Fabiano Aguiari

2007 ◽  
Vol 24 (2) ◽  
pp. 270-284 ◽  
Author(s):  
Harvey E. Seim ◽  
Catherine R. Edwards

Abstract Simultaneous ADCP profile measurements are compared over a 2-month period in late 2003. One set of measurements comes from a National Data Buoy Center (NDBC) buoy-mounted ADCP, the other from a bottom-mounted, upward-looking ADCP moored roughly 500 m from the buoy. The study was undertaken to evaluate the proficiency of an experimental configuration by NDBC; unfortunately, the ADCP was not optimally configured. The higher temporally and vertically resolved bottom-mounted ADCP data are interpolated in time and depth to match the buoy-mounted ADCP measurements. It is found that the two ADCP measurements are significantly different. The buoy-mounted measurements are affected by high-frequency (<10 h period) noise that is vertically coherent throughout the profiles. This noise results in autospectra that are essentially white, unlike the classic red spectra formed from the bottom-mounted ADCP observations. The spectra imply a practical noise floor of 0.045 m s−1 for the buoy-mounted system. Contamination by surface waves is the likely cause of this problem. At tidal frequencies the buoy-mounted system underestimates major axis tidal current magnitude by 10%–40%; interference from the buoy chain and/or fish or plankton are considered the most likely cause of the bias. The subtidal velocity field (periods greater than 40 h) is only partially captured; the correlation coefficient for the east–west current is 0.49 and for the north–south current is 0.64.


2019 ◽  
Vol 49 (2) ◽  
pp. 329-352 ◽  
Author(s):  
Pengcheng Wang ◽  
Zhongjie He ◽  
Keith R. Thompson ◽  
Jinyu Sheng

AbstractNear-inertial oscillations (NIOs) on the inner Scotian shelf are studied using observations, a simple slab model, and two operational shelf circulation models. High-frequency radar and ADCP observations from December 2015 to February 2016 show that individual NIO events forced by time-varying wind stress typically lasted for three to four inertial periods. NIOs with speeds exceeding 0.25 m s−1 were observed in the offshore part of the study region, but their amplitudes decreased shoreward within ~40 km of the coast. The NIOs had spatial scales of ~80 and ~40 km in the alongshore and cross-shore directions, respectively. The NIO phases varied moving from west to east, consistent with the typical movement of winter storms across the study region. Evolving rotary spectral analysis reveals that the peak frequency fp of the NIOs varied with time by ~7% of the local inertial frequency. The variation in fp can be explained in part by local wind forcing as demonstrated by the slab model. The remaining variation in fp can be explained in part by variations in the background vorticity associated with changes in the strength and position of the Nova Scotia Current, an unstable baroclinic boundary current that runs along the coast to the southwest. Two operational shelf circulation models are used to examine the abovementioned features in the high-frequency-radar and ADCP observations. The models reproduce the spatial structure of the NIOs and, in a qualitative sense, the temporal variations of fp.


2018 ◽  
Vol 157 ◽  
pp. 03016
Author(s):  
Alzbeta Sapietova ◽  
Vladimír Dekys ◽  
Milan Sapieta ◽  
Peter Sulka ◽  
Lukas Gajdos ◽  
...  

The paper presents an analysis of impact force on stopper screw in axial piston hydraulic motor. The solution contains probabilistic description of input variables. If the output parameters of probabilistic solution are compared with arbitrary values and values acquired by analytical solution, the probability of proper operation of the device can be evaluated.


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