996 research outputs found

    Decomposing changes in first birth trends : quantum, timing, or variance

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    In high-income countries, women and men born since the 1940s have delayed the birth of their first child, more of them have remained childless, and the timing of the first birth has become more diverse in these cohorts. The interaction between these three trends makes the research on first birth patterns more complex. This study has two main aims: (1) we introduce an alternative index, Expected Years Without Children (EYWC), to quantify changes in first birth behaviour; and (2) we decompose the changes in EYWC over time into three effects: remaining permanently childless, postponing the first birth, and the expansion of the standard deviation of the mean age at first birth. Using data from the Human Fertility Database, EYWC is calculated to illustrate time trends among women born in the 1910s-1960s in eight countries with longer series of data on cohort first birth trends: Canada, the Czech Republic, Japan, the Netherlands, Norway, Portugal, Sweden, and the United States. Our decomposition shows that the changes in EYWC are mainly attributable to postponement in North America and northern Europe, whereas these changes are largely due to increasing shares of women remaining childless in Japan and Portugal

    Analisis Pencatatan dan Pelaporan Aset Tetap pada Pemerintah Kabupaten Kepulauan Sangihe Tahun 2011 (Studi Kasus pada Dinas Ppkad Selaku Skpkd)

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    Local governments are reguired to make accountability reports that use accounting system that is set by the central government in the form of law – laws and regulations that are binding on all Government local government. Therefore, each Regional Financial Management Unit ( SKPKD ) must prepare its financial statements based on the government regulation number 24 of the Minister of home affairs Number 59 year 2007, which is an amandement to Permendagri N0. 13 year 2006 on guidelines financial Management.The research was conducted in Sangihe regency, which in this study, analyzed fixed asset Recording and Reporting on Local Government in this case the Departement of finance and revenue management as a Regional Asset SKPKD for fiscal year 2011.The purpose of this study is to analyzed the suitability of the recording and reporting of fixed assets in Sangihe regency government especially the Departement of revenue in the finance and asset management areas as SKPKD to financial statements in financial report balance Sangihe islanda District government with government regulation No. 24 year 2005 on standards government accounting and No. 13 year 2006 on Regional Financial Management Guidelslines.The study uses a descriptive research design in the form of case studies. Type of data used is quantitative data that figures-figures in the Balance sheet. The author uses the method library research, field surveys, and documentation required for data collection.The results showed that, Sangihe regency government has done the recording and reporting of fixed assets with good, though not fully in accordance with government Regulation No. 24 year 2005 regarding the Regulation of the minister and the government accounting standards of 2007 because the 2011 financial statements opinion gets no opinion ( Disclaimer Opinion) by CPC caused by asset accounting. However, the financial statements have been prepared in time to be used for the users as decision makers and as refence for the preparation of financial statements with fiscal year 2012 and in accordance with government accounting standards

    Failure time and microcrack nucleation

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    The failure time of samples of heterogeneous materials (wood, fiberglass) is studied as a function of the applied stress. It is shown that in these materials the failure time is predicted with a good accuracy by a model of microcrack nucleation proposed by Pomeau. It is also shown that the crack growth process presents critical features when the failure time is approached.Comment: 13 pages, 4 figures, submitted to Europhysics Letter

    Electronic excitation of carbonyl sulphide (COS) by high-resolution vacuum ultraviolet photoabsorption and electron-impact spectroscopy in the energy region from 4 to 11 eV

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    The electronic state spectroscopy of carbonyl sulphide, COS, has been investigated using high resolution vacuum ultraviolet photoabsorption spectroscopy and electron energy loss spectroscopy in the energy range of 4.0–10.8 eV. The spectrum reveals several new features not previously reported in the literature. Vibronic structure has been observed, notably in the low energy absorption dipole forbidden band assigned to the (4π←3π) (1Δ←1Σ+) transition, with a new weak transition assigned to (1Σ−←1Σ+) reported here for the first time. The absolute optical oscillator strengths are determined for ground state to 1Σ+ and 1Π transitions. Based on our recent measurements of differential cross sections for the optically allowed (1Σ+ and 1Π) transitions of COS by electron impact, the optical oscillator strength f0 value and integral cross sections (ICSs) are derived by applying a generalized oscillator strength analysis. Subsequently, ICSs predicted by the scaling are confirmed down to 60 eV in the intermediate energy region. The measured absolute photoabsorption cross sections have been used to calculate the photolysis lifetime of carbonyl sulphide in the upper stratosphere (20–50 km)

    The critical earthquake concept applied to mine rockbursts with time-to-failure analysis

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    We report new tests of the critical earthquake concepts performed on rockbursts in deep South African mines. We extend the concept of an optimal time and space correlation region and test it on the eight main shocks of our catalog provided by ISSI. In a first test, we use the simplest signature of criticality in terms of a power law time-to-failure formula. Notwithstanding the fact that the search for the optimal correlation size is performed with this simple power law, we find evidence both for accelerated seismicity and for the presence of logperiodic behavior with a prefered scaling factor close to 2. We then propose a new algorithm based on a space and time smoothing procedure, which is also intended to account for the finite range and time mechanical interactions between events. This new algorithm provides a much more robust and efficient construction of the optimal correlation region, which allows us the use of the logperiodic formula directly in the search process. In this preliminary work, we have only tested the new algorithm on the largest event on the catalog. The result is of remarkable good quality with a dramatic improvement in accuracy and robustness. This confirms the potential importance of logperiodic signals. Our study opens the road for an efficient implemention of a systematic testing procedure of real-time predictions.Comment: 22 pages, 32 figure

    The Influence of Viscoelastic Crustal Rheologies on Volcanic Ground Deformation: Insights from Models of Pressure and Volume Change

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    This is the final version. Avaialble on open access from Wiley via the DOI in this recordInelastic rheological behaviour, such as viscoelasticity, is increasingly utilised in the modelling of volcanic ground deformation, as elevated thermal regimes induced by magmatic systems may necessitate the use of a mechanical model containing a component of time-dependent viscous behaviour. For the modelling of a given amplitude and footprint of ground deformation, incorporating a viscoelastic regime has been shown to reduce the magma reservoir overpressure requirements suggested by elastic models. This phenomenon, however, is restricted to pressure-based analyses and the associated creep behaviour. Viscoelastic materials exhibit additional constitutive time-dependent behaviours, determined by the stress and strain states, that are yet to be analysed in the context of volcanic ground deformation. By utilising a mechanically homogeneous model-space and distinct reservoir evolutions, we provide a comparison of three viscoelastic rheological models, including the commonly implemented Maxwell and Standard Linear Solid configurations, and their time-dependent behaviours from a fundamental perspective. We also investigate the differences between deformation timeseries resulting from a pressurisation or volume change; two contrasting approaches that are assumed to be equivalent through elastic modelling. Our results illustrate that the perceived influence of viscoelasticity is dependent on the mode of deformation, with stress-based pressurisation models imparting enhanced deformation relative to the elastic models, thus reducing pressure requirements. Strain-based volumetric models, however, exhibit reduced levels of deformation and may produce episodes of apparent ground subsidence induced by source inflation or vice versa, due to the relaxation of crustal stresses, dependent on whether the reservoir is modelled to be expanding or contracting, respectively.Natural Environment Research Council (NERC
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