A Generalized Magnetospheric Disturbance Index: Initial Application to Mars Using MAVEN Observations

When comparing with ship construction within newly-built docks or on tilting slipways, ship constructing on the flat earth method can be said to be a new ship-building technique by which ship is built on a platform and launched with the aid of floating-dock or barge. Some obvious advantages of this technique are such as less investment in basic facilities, low production cost, high production efficiency, wide applicability of ship types, ability to overcome the bottle-neck effect of berths and docks. In this paper, a bulk-carrier being taken as an example, the design of launching processing scheme on the horizontal shipway includes calculation of launching weight and determination of hoisting force during the whole towing period. The whole towing process of hull can be divided into three stages, the first is from the static state to the moment of beginning to move, the second is from the initial position of movement to the front of slipway onto which the hull is predicted to be pulled, and the third is from the front of slipway to the designated position on the floating dock. Subsequently, after the hull being sealed and positioned correctly, the floating dock for launching may be towed to deeper water zone and the hull can be buoyed up on the water surface, and the whole launching process can be completed. From the research, the conclusion is made that the launching technique of this paper is available and feasible. Especially, this paper is the initial application of this method on the 15000t launching ship home and has the epoch-making sense.

Download Full-text

Integrated Unit Technology for Gas Field Surface Gathering and Transmission

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.271-272.1328 ◽

2012 ◽

Vol 271-272 ◽

pp. 1328-1345

Author(s):

Jin Li ◽

Jian Yang Zhao

Keyword(s):

Natural Gas ◽

Power Consumption ◽

New Technologies ◽

Ball Valve ◽

Gas Field ◽

Pneumatic Control ◽

Initial Application ◽

Design Idea

In combination with the author's experiences in design for integrated unit for natural gas field gathering and transmission, this paper describes conventional practices and technical characteristics of integrated unit in the processes of standardization design and modularization establishment and analyzes the initial application of pneumatic control ball valve, wedge-shaped flowmeter and other new technologies for surface facilities in the gas field. As a result, a new design idea is proposed in this paper, i.e., to improve the integration level of surface facilities, to minimize power consumption and maintenance works and to realize unattended work mode.

Download Full-text

Retrospectives: The Introduction of the Cobb–Douglas Regression

The Journal of Economic Perspectives ◽

10.1257/jep.26.2.223 ◽

2012 ◽

Vol 26 (2) ◽

pp. 223-236 ◽

Cited By ~ 15

Author(s):

Jeff Biddle

Keyword(s):

Time Series Data ◽

Series Data ◽

Mathematical Representation ◽

Least Squares Regression ◽

Empirical Measures ◽

Stable Relationship ◽

Initial Application ◽

Economic Association ◽

The Relationship ◽

Theory Of Production

At the 1927 meetings of the American Economic Association, Paul Douglas presented a paper entitled “A Theory of Production,” which he had coauthored with Charles Cobb. The paper proposed the now familiar Cobb–Douglas function as a mathematical representation of the relationship between capital, labor, and output. The paper's innovation, however, was not the function itself, which had originally been proposed by Knut Wicksell, but the use of the function as the basis of a statistical procedure for estimating the relationship between inputs and output. The paper's least squares regression of the log of the output-to-capital ratio in manufacturing on the log of the labor-to-capital ratio—the first Cobb–Douglas regression—was a realization of Douglas's innovative vision that a stable relationship between empirical measures of inputs and outputs could be discovered through statistical analysis, and that this stable relationship could cast light on important questions of economic theory and policy. This essay provides an account of the introduction of the Cobb–Douglas regression: its roots in Douglas's own work and in trends in economics in the 1920s, its initial application to time series data in the 1927 paper and Douglas's 1934 book The Theory of Wages, and the early reactions of economists to this new empirical tool.

Download Full-text

Compared to Individuals with Mild to Moderate Obstructive Sleep Apnea (OSA), Individuals with Severe OSA Had Higher BMI and Respiratory-Disturbance Scores

Life ◽

10.3390/life11050368 ◽

2021 ◽

Vol 11 (5) ◽

pp. 368

Author(s):

Leeba Rezaie ◽

Soroush Maazinezhad ◽

Donald J. Fogelberg ◽

Habibolah Khazaie ◽

Dena Sadeghi-Bahmani ◽

...

Keyword(s):

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Multiple Regression ◽

Daytime Sleepiness ◽

Respiratory Disturbance Index ◽

Disturbance Index ◽

Related Data ◽

Obstructive Sleep ◽

Increased Risk ◽

Respiratory Disturbance

Objective: Individuals with obstructive sleep apnea (OSA) are at increased risk to suffer from further somatic and sleep-related complaints. To assess OSA, demographic, anthropometric, and subjective/objective sleep parameters are taken into consideration, but often separately. Here, we entered demographic, anthropometric, subjective, and objective sleep- and breathing-related dimensions in one model. Methods: We reviewed the demographic, anthropometric, subjective and objective sleep- and breathing-related data, and polysomnographic records of 251 individuals with diagnosed OSA. OSA was considered as a continuous and as categorical variable (mild, moderate, and severe OSA). A series of correlational computations, X2-tests, F-tests, and a multiple regression model were performed to investigate which demographic, anthropometric, and subjective and objective sleep dimensions were associated with and predicted dimensions of OSA. Results: Higher apnea/hypopnea index (AHI) scores were associated with higher BMI, higher daytime sleepiness, a higher respiratory disturbance index, and higher snoring. Compared to individuals with mild to moderate OSA, individuals with severe OSA had a higher BMI, a higher respiratory disturbance index (RDI) and a higher snoring index, while subjective sleep quality and daytime sleepiness did not differ. Results from the multiple regression analysis showed that an objectively shorter sleep duration, more N2 sleep, and a higher RDI predicted AHI scores. Conclusion: The pattern of results suggests that blending demographic, anthropometric, and subjective/objective sleep- and breathing-related data enabled more effective discrimination of individuals at higher risk for OSA. The results are of practical and clinical importance: demographic, anthropometric, and breathing-related issues derived from self-rating scales provide a quick and reliable identification of individuals at risk of OSA; objective assessments provide further certainty and reliability.

Download Full-text

3 per cent-accurate predictions for the clustering of dark matter, haloes, and subhaloes, over a wide range of cosmologies and scales

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3117 ◽

2020 ◽

Vol 499 (4) ◽

pp. 4905-4917

Author(s):

S Contreras ◽

R E Angulo ◽

M Zennaro ◽

G Aricò ◽

M Pellejero-Ibañez

Keyword(s):

Dark Matter ◽

Spatial Distribution ◽

Cosmological Parameters ◽

Galaxy Surveys ◽

Circular Velocity ◽

Initial Application ◽

Wide Range ◽

Massive Neutrinos ◽

Dynamical Dark Energy ◽

Better Than

ABSTRACT Predicting the spatial distribution of objects as a function of cosmology is an essential ingredient for the exploitation of future galaxy surveys. In this paper, we show that a specially designed suite of gravity-only simulations together with cosmology-rescaling algorithms can provide the clustering of dark matter, haloes, and subhaloes with high precision. Specifically, with only three N-body simulations, we obtain the power spectrum of dark matter at z = 0 and 1 to better than 3 per cent precision for essentially all currently viable values of eight cosmological parameters, including massive neutrinos and dynamical dark energy, and over the whole range of scales explored, 0.03 < $k/{h}^{-1}\, {\rm Mpc}^{-1}$ < 5. This precision holds at the same level for mass-selected haloes and for subhaloes selected according to their peak maximum circular velocity. As an initial application of these predictions, we successfully constrain Ωm, σ8, and the scatter in subhalo-abundance-matching employing the projected correlation function of mock SDSS galaxies.

Download Full-text

Study of the floristic diversity of Acacia tortilis population- in Bechar region (Southwestern Algeria)

South Asian Journal of Experimental Biology ◽

10.38150/sajeb.9(4).p133-141 ◽

2019 ◽

Vol 9 (4) ◽

pp. 133-141

Author(s):

Guenaia Abdelkader ◽

Hasnaoui Okkacha ◽

Bekkouche Assia

Keyword(s):

Sustainable Use ◽

Diversity Indices ◽

Floristic Diversity ◽

Acacia Tortilis ◽

Important Species ◽

Disturbance Index ◽

Moricandia Arvensis ◽

Biological Spectrum ◽

Flora Diversity ◽

Risk Loss

For the management and sustainable use of natural bio-resources it is necessary to quantify and valorize this heritage. In the case of the floristic diversity of Acacia tortilis, the only natural woody stand in Bechar-Algeria, scanty studies have been undertaken. Hence in this study, the general overview of the flora diversity state in the 58 plots of 9 stations was made by the analysis of various indexes: Shannon, Simpson, species evenness, floristic richness, disturbance index, biological and biogeographically spectra. We listed 103 species belonging to 37 families and 85 genus, the important plants belonged to the Asteraceae and Brassicaceae. The most important species are: Pulicaria crispa, Asteriscus graveolens, Launea arborescens, Matricaria pubescens, Moricandia arvensis, Farsetia aegyptiaca, Zilla macroptera. The biological spectrum indicated a dominance of the Chamaephytes and the predominance of the Therophytes; the phytogeographic spectrum showed an important endemism (44%) in which 36% species belong to the SaharoArabian element; The Shannon, Simpson, and Evenness diversity indices, were relatively high, thereby indicating a diversity variation between the stations, witch increased South towards North. It was prominent in Zouzfana, Taghit, and Abadla stations, and the higher values of disturbance Index reflected the greater level of anthropization in these courses. The future accumulation of this regression, many risk loss of the last naturally wall of desertification, biodiversity, national economy and sand advancement. Therefore, it is recommended to apply pastures protection, pastoral charge control, and elaborate an environmental value of this species.

Download Full-text