scholarly journals Estimating the short-time rate of change in the trend of the Keeling curve

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Sven Nordebo ◽  
Muhammad Farhan Naeem ◽  
Pieter Tans
Keyword(s):  
Rate Of Change ◽  
Series Expansions ◽  
Natural Phenomena ◽  
Smoothing Technique ◽  
Time Rate ◽  
Data Window ◽  
Simple Strategy ◽  
Analysis Technique ◽  
Definition Of ◽  
Short Time

AbstractWhat exactly is the short-time rate of change (growth rate) in the trend of $$\text {CO}_2$$ CO 2 data such as the Keeling curve? The answer to this question will obviously depend very much on the duration in time over which the trend has been defined, as well as the smoothing technique that has been used. As an estimate of the short-time rate of change we propose to employ a very simple and robust definition of the trend based on a centered 1-year sliding data window for averaging and a corresponding centered 1-year difference (2-year data window) to estimate its rate of change. In this paper, we show that this simple strategy applied to weekly data of the Keeling curve (1974–2020) gives an estimated rate of change which is perfectly consistent with a more sophisticated regression analysis technique based on Taylor and Fourier series expansions. From a statistical analysis of the regression model and by using the Cramér–Rao lower bound, it is demonstrated that the relative error in the estimated rate of change is less than 5 $$\%$$ % . As an illustration, the estimates are finally compared to some other publicly available data regarding anthropogenic $$\text {CO}_2$$ CO 2 emissions and natural phenomena such as the El Niño.

scholarly journals Review of Studies on Older Drivers’ Behavior and Stress—Methods, Results, and Outlook

Sensors ◽  
2021 ◽  
Vol 21 (10) ◽  
pp. 3503
Author(s):  
Yanning Zhao ◽  
Toshiyuki Yamamoto
Keyword(s):  
Age Groups ◽  
Older Drivers ◽  
Driving Simulators ◽  
Driving Experience ◽  
Older Driver ◽  
Vehicle Data ◽  
Vehicle Systems ◽  
Questionnaire Surveys ◽  
Definition Of ◽  
Short Time

This paper presents a review on relevant studies and reports related to older drivers’ behavior and stress. Questionnaires, simulators, and on-road/in-vehicle systems are used to collect driving data in most studies. In addition, research either directly compares older drivers and the other drivers or considers participants according to various age groups. Nevertheless, the definition of ‘older driver’ varies not only across studies but also across different government reports. Although questionnaire surveys are widely used to affordably obtain massive data in a short time, they lack objectivity. In contrast, biomedical information can increase the reliability of a driving stress assessment when collected in environments such as driving simulators and on-road experiments. Various studies determined that driving behavior and stress remain stable regardless of age, whereas others reported degradation of driving abilities and increased driving stress among older drivers. Instead of age, many researchers recommended considering other influencing factors, such as gender, living area, and driving experience. To mitigate bias in findings, this literature review suggests a hybrid method by applying surveys and collecting on-road/in-vehicle data.

STUDY OF PHASE PROPAGATION IN SUPERCONDUCTING ALUMINUM BY ULTRASONIC ATTENUATION MEASUREMENTS

1959 ◽  
Vol 37 (5) ◽  
pp. 614-618 ◽  
Author(s):  
K. L. Chopra ◽  
T. S. Hutchison
Keyword(s):  
Magnetic Field ◽  
Eddy Current ◽  
Ultrasonic Attenuation ◽  
Cylindrical Specimen ◽  
Current Theory ◽  
Superconducting Phase ◽  
Rate Of Change ◽  
Time Rate ◽  
Phase Propagation ◽  
The Magnetic Field

The phase propagation in superconducting aluminum has been studied by measuring the time rate of change of ultrasonic attenuation. The time taken for the destruction of the superconducting phase in a cylindrical specimen, by means of a magnetic field, H, greater than the critical field, Hc, is approximately proportional to{H/(H–Hc)} in agreement with eddy-current theory. In the converse case, where the superconducting phase is restored by switching off the magnetic field H (>Hc), the total time taken is nearly independent of the temperature (or Hc) as well as H. The superconducting phase grows at a non-uniform volume rate which is considerably less than the uniform rate of collapse.

scholarly journals Upaya Meningkatkan Kreativitas Anak melalui Permainan Finger Painting Usia 5-6 Tahun di TK Harapan Bunda Pekanbaru

2018 ◽  
Vol 2 (01) ◽  
pp. 31-39
Author(s):  
Jumilah Jumilah ◽  
Sean Marta Efastri ◽  
Siti Fadillah
Keyword(s):  
Initial Data ◽  
Key Words ◽  
Average Increase ◽  
Research Results ◽  
Class Actions ◽  
Analysis Technique ◽  
Determination Methods ◽  
Definition Of ◽  
Children's Development ◽  
Children’S Development

Abstrak Kreativitas adalah kemampuan untuk menciptakan sesuatu yang baru yang berupa gagasan maupun karya nyata. Adapun tujuan dari penelitian yaitu untuk mendapatkan data perkembangan kreativitas anak  melalui permainan finger painting. Metode penelitian yang digunakan adalah Penelitian Tindakan Kelas ( PTK) . Subjek yang diambil untuk penelitian  terdiri dari 15 anak di TK Harapan Bunda. Teknik pengumpulan data dalam penelitian ini adalah melalui lembar observasi, dan dokumentasi. Teknik analisis data yaitu dengan menggunakan rumus persentase= f/n x100 % . Hasil penelitian data yang diperoleh  dalam meningkatkan perkembangan kreativitas anak melalui permainan finger painting, sebelum tindakan adalah 59 %  ( Mulai Berkembang / MB ) dan meningkat pada siklus I dengan kategori BSH “ Berkembang Sesuai Harapan”  dengan rata – rata peningkatan 71 % dan pada siklus II mengalami peningkatan dengan kategori BSB “ Berkembang Sangat Baik” yaitu rata-rata 84 %. Jadi peningkatan kreativitas anak dari data awal 59 %  ke data siklus II 84 %, terjadi peningkatan sebanyak 25 %.    Kata  Kunci :  Kreativitas Anak,   permainan  finger painting Abstract Creativity is the ability to create a new something which is in the form of ideas or real works. There is a purpose of definition that is to get data of children's development creativity through Finger painting games. Determination methods used are definition of class actions (ptk). Observation sheet, and documentation. Analysis technique is using the percentage formula f / n x 100%. The research results obtained in improving the development of children's creativity through finger painting, before the action was 59% (developing / mb) and increasing in the first cycle with the bsh category "developing as expected" with an average increase of 71% and in the second cycle experiencing an increase with the bsb category "develops very well" which is an average of 84%. So increasing children's creativity from the initial data of 59% to data cycle ii 84%, an increase of 25%. Key words : children's creativity, finger painting game

346. Measurements of the rate of change of temperature in high temperature-short time pasteurization plant

1947 ◽  
Vol 15 (1-2) ◽  
pp. 18-23
Author(s):  
F. Steghart
Keyword(s):  
High Temperature ◽  
Time Constant ◽  
Rate Of Change ◽  
Hot Water ◽  
Water Pipe ◽  
Temperature Changes ◽  
Rates Of Change ◽  
High Temperature Short Time ◽  
Short Time

It has recently been claimed that in modern high temperature-short time pasteurization plant fluctuations in temperature of the order of 1° F./sec. are unusual and probably artefacts, and that an instantaneous drop is certainly fictitious.It has, nevertheless, been shown that such rapid drops in temperature do in fact occur frequently in high temperature-short time plants of the type investigated. The plant investigated was not of the latest design incorporating devices for speeding up the control by injecting steam directly into the hot-water pipe.Temperature changes of the order of those in question were first observed by Mattick & Hiscox(1) of the National Institute for Research in Dairying, who carried out tests on pasteurization plant using a small mirror galvanometer with a very short time constant. The maximum rates of change were, however, not observed.

Instantaneous Identification of Polynomial Nonlinearity Based on Volterra Series Representation

2005 ◽  
Vol 293-294 ◽  
pp. 703-710 ◽  
Author(s):  
Giacomo V. Demarie ◽  
Rosario Ceravolo ◽  
Alessandro de Stefano
Keyword(s):  
Structural Engineering ◽  
Volterra Series ◽  
Series Representation ◽  
Consistent Estimate ◽  
Short Time Fourier Transform ◽  
Dynamic Identification ◽  
Polynomial Nonlinearity ◽  
Definition Of ◽  
Short Time

In structural engineering applications a sufficient quantity of experimental data to be able to achieve a consistent estimate of nonlinear quantities is seldom available: this applies in particular when the structures are to be tested in situ. This report discusses the definition of instantaneous estimators to be used in the dynamic identification of invariant nonlinear systems on the basis of Short-Time Fourier Transform representation of excitation and system’s response and within the framework of a Volterra series representation of the input/output relationship. An estimation of the parameters of a dynamic system can be worked out from the evolution of such instantaneous estimators.

Cosmic-Ray Energy Changes

1974 ◽  
Vol 2 (5) ◽  
pp. 297-299 ◽  
Author(s):  
L. J. Gleeson ◽  
G. M. Webb
Keyword(s):  
Cosmic Rays ◽  
Current Density ◽  
Cosmic Ray ◽  
Rate Of Change ◽  
Time Rate ◽  
Differential Current

The purpose of this paper is to provide a new expression for < ṗ > the average time-rate-of-change of momentum of cosmic-ray particles propagating in the interplanetary region. The expression derived replaces the previously used adiabatic deceleration formula and it is arrived at by a rearrangement and reinterpretation of the well known equation of transport for cosmic-rays. Thus, although we provide a new expression for < ṗ > we maintain the equation of transport and do not render invalid results for differential intensity and differential current density of cosmic-ray particles obtained by its solution (Jokipii 1971; Gleeson 1972).

Sound and turbulence modulation by particles in high-speed shear flows

2019 ◽  
Vol 875 ◽  
pp. 254-285 ◽  
Author(s):  
David A. Buchta ◽  
Gregory Shallcross ◽  
Jesse Capecelatro
Keyword(s):  
Gas Phase ◽  
High Speed ◽  
Pressure Fluctuations ◽  
Sound Radiation ◽  
Rate Of Change ◽  
Intensity Increase ◽  
Mass Loading ◽  
Local Pressure ◽  
Time Rate ◽  
Particle Laden Flows

High-speed free-shear-flow turbulence, laden with droplets or particles, can radiate weaker pressure fluctuations than its unladen counterpart. In this study, Eulerian–Lagrangian simulations of high-speed temporally evolving shear layers laden with monodisperse, adiabatic, inertial particles are used to examine particle–turbulence interactions and their effect on radiated pressure fluctuations. An evolution equation for gas-phase pressure intensity is formulated for particle-laden flows, and local mechanisms of pressure changes are quantified over a range of Mach numbers and particle mass loadings. Particle–turbulence interactions alter the local pressure intensity directly via volume displacement (due to the flow of finite-size particles) and drag coupling (due to local slip velocity between phases), and indirectly through significant turbulence changes. The sound radiation intensity near subsonic mixing layers increases with mass loading, consistent with existing low Mach number theory. For supersonic flows, sound levels decrease with mass loading, consistent with trends observed in previous experiments. Particle-laden cases exhibit reduced turbulent kinetic energy compared to single-phase flow, providing one source of their sound changes; however, the subsonic flow does not support such an obvious source-to-sound decomposition to explain its sound intensity increase. Despite its decrease in turbulence intensity, the louder particle-laden subsonic flows show an increase in the magnitude and time-rate-of-change of fluid dilatation, providing a mechanism for its increased sound radiation. Contrasting this, the quieter supersonic particle-laden flows exhibit decreased gas-phase dilatation yet its time-rate-of-change is relatively insensitive to mass loading, supporting such a connection.

scholarly journals (Re)conceptualizing “Polydrug Use”: Capturing the Complexity of Combining Substances

2019 ◽  
Vol 46 (4) ◽  
pp. 400-417 ◽  
Author(s):  
Pekka Hakkarainen ◽  
Aileen O’Gorman ◽  
François Lamy ◽  
Kati Kataja
Keyword(s):  
Social Science Research ◽  
Science Research ◽  
Time Frame ◽  
People Who Use Drugs ◽  
Cultural Meanings ◽  
Polydrug Use ◽  
Qualitative Case Studies ◽  
Sensory Effects ◽  
Definition Of ◽  
Short Time

The use of multiple psychoactive substances is a widespread phenomenon among people who use drugs. Yet the concept of polydrug use is poorly defined in the social sciences. As a result, theoretical and empirical knowledge of polydrug use is underdeveloped; approaches to measuring polydrug use are inconsistent; and understandings of the cultural meanings of combining substances are limited. This article draws on a collaborative synthesis of three qualitative case studies of polydrug use from four countries: Australia and France, Finland, and Ireland. All three studies explored the practice of substance combination, or “combos” using the lens of intentionality, functionality, and social setting. In addition, the studies shared a common concern with teasing out the rationale for substance combining, and the controls used to balance pleasures with risks, beyond the simple physiological or sensory effects of substances. Our analysis leads us to recommend that a standard definition of polydrug use be adopted for future social science research—that is, the ingestion of two or more substances in combination, at the same time or in temporal proximity, so that the effects of different substances overlap. For analytical purposes, we suggest two subcategories: simultaneous and sequential intake. Moreover, we contend that it is the intention, meaning, and socio-structural context underpinning the use of substance combinations that is central to understanding polydrug use. Consequently, we suggest an adaptation of Zinberg’s seminal concept to one of “drug combo, set, and setting” to incorporate an analysis of the effects of using substances together, or in sequence within a short time frame.

The Applicated Comparation of Three Signal Analytical Methods for Ocean CSEM Signature

2013 ◽  
Vol 798-799 ◽  
pp. 561-564
Author(s):  
Ji Yu Zhou ◽  
Feng Dao Zhou
Keyword(s):  
Frequency Analysis ◽  
Oil And Gas ◽  
Time Frequency Analysis ◽  
Hilbert Huang Transform ◽  
Time Frequency ◽  
Analysis Technique ◽  
Oil And Gas Resources ◽  
Concentration Degree ◽  
Short Time ◽  
Better Than

Sea is rich in oil and gas resources, the marine controlled source electromagnetic method (CSEM) is a kind of method seabed oil gas geophysical technology rising in recent years. Because of the problem of CSEM about the air wave in the shallow water, the research of time-frequnecy analysis technique is used to suppress the air wave in this paper. The basic idea is: because of the CSEM signals speed are different in the air and submarine, so the time which received by the receiving points are also different through these two kinds of ways. Using the time-frequency analysis technique and theoretical calculation, we can determine which part of the signal is spread over the ocean, so as to suppress the air wave effectively. This paper lists several methods of time-frequency analysis, such as Short-time Fourier transform, W-V distribution, Wavelet transform, Hilbert Huang transform. Through the time-frequency graph,we get the conclusion that HHT is better than others in concentration degree,and W-V distribution is better than STFT.Compared with the original signal, the time-frequency graph is the best in using Smooth Puseudo W-V Distribution.I have a detailed analysis about real case in using SPWVD at last.

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