Miracle-dz/UniFAR-FTUs huggingface dataset:
Structural Safety Evaluation of Steel Jacket Platforms

This paper describes an attempt to bring a state of the art methodology to the state of practice. The methodology aims at the evaluation of the failure probability of a steel-jacket platform under extreme environmental loading conditions. Of course, this probability of failure should not be considered as the “true” probability of failure of the ~:+~:ture over a particular period of but simply as an overall safety measure to be used as a decision tool . In short, it is based on a search for the most probable contponent fai Lure sequences leading to the structure collapse. Componental fai lures include brace buckling, plastification of a section, and punching of a chord by a brace.
Researching Motivation in Context: Rethinking Methodologies.

Recent theory and research on motivation has shifted in its focus from a study of more general characteristics of individuals such as personal motivational goals, to an examination of the motivation of individuals within specific domains or contexts. This change in focus has led to a broadening of the methodologies used to examine motivation. Many studies now use mixed methods. Rather than relying almost exclusively on quantitative measures such as questionnaires, researchers are incorporating qualitative measures to capture the dynamic and rich nature of learning and motivation in context. This presentation will illustrate the above trend. The presenter's work in progress will be used to discuss how insights into motivation in context might be obtained using qualitative research methodologies. Participants from the domains of sport and music have been interviewed using a range of specially designed stimulus materials and tasks to gain an understanding of their experiences within these contexts. This approach elicited participants' stories of their development and the people involved, as well as their perceptions of the different settings in which they play sport or music. Participants were asked to consider both positive and negative influences on motivation. Contains 40 references, and 3 tables and 5 figures of data. (Author/RS) Reproductions supplied by EDRS are the best that can be made from the original document. AARE (AUSTRALIAN ASSOCIATION FOR RESEARCH IN EDUCATION) ANNUAL CONFERENCE, FREMANTLE, DECEMBER, 2001 U.S. DEPARTMENT OF EDUCATION Office of Educational Research and Improvement EDUCATIONAL RESOURCES INFORMATION CENTER (ERIC) This document has been reproduced as received from the person or organization originating it. Minor changes have been made to improve reproduction quality. Points of view or opinions stated in this document do not necessarily represent official OERI position or policy. Researching Motivation in Context: Rethinking Methodologies.
Numerical Simulation of the Dwarf Companions of Giant Galaxies

Abstract We report simulations of the formation of a giant disc galaxy from cosmological initial conditions. Two sets of initial conditions are used, initially smooth density for both gas and stars, representing the Warm dark Matter scenario, and an initially fluctuating density representing the standard spectrum for the Cold dark Matter scenario. For the WDM initial conditions, the galaxy has a population of long lived dwarf satellites at z = 0, with orbits close to a plane coincident with that of the giant galaxy disc. The detailed properties of these dwarfs mimic closely the observed properties of Local Group dwarfs with respect to mass, and kinematics. However they do not have individual dark matter halos, but orbit in the nearly spherical dark matter halo of the giant galaxy. The reason for this is that the initial population of dwarf dark matter haloes, which form during the initial collapse phase, all merge into the halo of the giant galaxy within a few to several Gyears, while the long lived dwarfs form as a secondary population by gravitational collapse of high angular momentum gas in the outer reaches of the giants proto-galactic disc. Due to their late formation and their more distant orbits, they survive until the present epoch as individual dwarf galaxies at radii 20-50kpc from the giants centre. For CDM initial conditions there are many more dwarf satellites at z = 0, some of which form early on as gas condensations in DM sub-halos, and survive with these individual DM halos till z = 0 due to their being sufficiently well bound to avoid merging with the main galaxy. However even in this case some second generation satellites form as initially gas only objects, just as for the smooth initial conditions of WDM.
Freshness constraints of an age of information based event-triggered Kalman consensus filter algorithm over a wireless sensor network

This paper presents the design of a new event-triggered Kalman consensus filter (ET-KCF) algorithm for use over a wireless sensor network (WSN). This algorithm is based on information freshness, which is calculated as the age of information (AoI) of the sampled data. The proposed algorithm integrates the traditional event-triggered mechanism, information freshness calculation method, and Kalman consensus filter (KCF) algorithm to estimate the concentrations of pollutants in the aircraft more efficiently. The proposed method also considers the influence of data packet loss and the aircraft’s loss of communication path over the WSN, and presents an AoI-freshness-based threshold selection method for the ET-KCF algorithm, which compares the packet AoI to the minimum average AoI of the system. This method can obviously reduce the energy consumption because the transmission of expired information is reduced. Finally, the convergence of the algorithm is proved using the Lyapunov stability theory and matrix theory. Simulation results show that this algorithm has better fault tolerance compared to the existing KCF and lower power consumption than other ET-KCFs.
Optimal control of a reflection boundary coefficient in an acoustic wave equation

We seek to optimally control a reflection boundary coefficient for an acoustic wave equation. The goal-quantified by an objective functional- is to drive the solution close to a target by adjusting this coefficient, which acts as a control. The problem is solved by finding the optimal control, which minimizes the objective functional. Then the optimal control is used as a an approximation for an inverse “ identification” problem.
Terahertz electrical and optical characteristics of double-walled carbon nanotubes and their comparison with single-walled carbon nanotubes

The electrical and optical properties of double-walled carbon nanotubes (DWNTs) have been characterized and compared with those of single-walled carbon nanotubes (SWNTs) utilizing terahertz time-domain spectroscopy. The power absorption and the complex refractive indices of DWNTs are smaller than those of SWNTs. The conductivity of DWNTs was also observed to be smaller. The experimental results have been fitted with the Bruggman effective medium approximations, which has yielded the transport parameters of DWNTs such as plasma frequency, damping rate, etc.
Images and Open Subspaces of SV Spaces

A topological space is finitely an F-space if its Stone–Čech compactification is a union of finitely many closed F-spaces and a space is SV if C(X) has the property that C(X)/P is a valuation domain for each prime ring ideal P of C(X). This article studies the images under open continuous functions and the open subspaces of spaces that are finitely an F-space or are SV. It is shown that an open continuous image of a compact space that is finitely an F-space is finitely an F-space and an open continuous image of certain SV spaces is SV. Also, it is shown cozerosets, but not necessarily open sets, of SV spaces are SV spaces and a similar situation holds for spaces that are finitely an F-space.
The International Journal of Biostatistics Relationship between Derivatives of the Observed and Full Loglikelihoods and Application to Newton-Raphson Algorithm

In the case of incomplete data we give general relationships between the first and second derivatives of the loglikelihood relative to the full and the incomplete observation set-ups. In the case where these quantities are easy to compute for the full observation set-up we propose to compute their analogue for the incomplete observation set-up using the above mentioned relationships: this involves numerical integrations. Once we are able to compute these quantities, Newton-Raphson type algorithms can be applied to find the maximum likelihood estimators, together with estimates of their variances. We detail the application of this approach to parametric multiplicative frailty models and we show that the method works well in practice using both a real data and a simulated example. The proposed algorithm outperforms a Newton-Raphson type algorithm using numerical derivatives.
Structure and Transport in the Solar Nebula from Constraints on Deuterium Enrichment and Giant Planets Formation

Abstract A simplified analytical model of an evolutionary nebula is used to generate temperature–density radial profiles following the procedure elaborated by Dubrulle ( Icarus 106 , 59, 1993). Each nebula disk is characterized by its initial mass M D , its initial radius R D , and the coefficient of turbulent viscosity α. We show that these parameters may be constrained by comparing temperature–density profiles to properly chosen physical and chemical Solar System data. Relatively weak constraints come from theories of formation of giant planets. The deuterium over hydrogen ratios observed in fossil water in primitive objects of the Solar System are much more constraining. For each model of the nebula, the temporal and radial evolution of the deuterium enrichment factor in water with respect to the protosolar abundance (in H 2 ) is calculated for the first time by integrating the equation of diffusion and is compared to observed deuterium enrichments in LL3 meteorites, giant planets, and comets. Observations cannot be fitted when we assume that H 2 O is uniquely produced in the hot inner part of the nebula. The agreement with observed data requires highly enriched deuterium ices initially infalling from the presolar cloud onto the whole nebula discoid. In order to fit measurements of D/H in LL3 meteorites, M D , R D , and α must be between 0.03 and 0.3 M ⊙ , 8 and 28 AU, and 0.003 and 1.0, respectively. The source of the turbulence consistent with these α values is discussed. High viscosity disks are characterized by MHD turbulence, while the low viscosity disks (α between 0.003 and 0.01) are characterized by hydrodynamical turbulence. Magnetic fields in the selected nebulae are also calculated. Their lifetime is found to be equal to 10 4 years for α=0.1 and 10 5 years for α=0.003. Scenarios providing us with an interpretation of the high D/H ratio observed in comets are discussed. The first scenario in which comets coming from the Oort cloud were formed very rapidly in the Uranus–Neptune region of the turbulent nebula and expelled toward the Oort cloud prior to the complete formation of these planets implies some reprocessing in the nebula of the cometary matter coming from the presolar cloud. It may not be easy however to expel comets toward the Oort cloud quite early in the history of the Solar System. It might be, according to the second scenario, that both comets coming from the Oort cloud and comets of the Jupiter family were formed farther than Neptune in a nonturbulent region of the nebula. In such a case, comets might have conserved to a large extent the chemical signature of the interstellar medium. Possible tests of the scenarios are considered.
Transformation of geometric models into orthogonal polyhedra using fuzzy logic

Purpose – This paper describes how non‐orthogonal geometric models may be transformed into orthogonal polyhedral models. The main purpose of the transformation is to obtain a geometric model that is easy to describe and further modify without loss of topological information from the original model.Design/methodology/approach – The transformation method presented in this paper is based on fuzzy logic (FL). The idea of using FL for this type of transformation was first described by Takahashi and Shimizu. This paper describes both philosophy and techniques behind the transformation method as well as its application to some example 2D and 3D models. The problem in this paper is to define a transformation technique that will change a non‐orthogonal model into a similar orthogonal model. The orthogonal model is unknown at the start of the transformation and will only be specified once the transformation is complete. The model has to satisfy certain conditions, i.e. it should be orthogonal.Findings – The group o.
White stork nest altitude decreases as global temperatures increase

Climate change causes altitudinal shifts of animal distributions and this effect can potentially be accentuated or altered due to human agricultural activities. Because of the availability of uniquely long-term monitoring data, we chose the white stork (Ciconia ciconia) as a model species. We analyzed large data sets (record cards from 1191 nests) covering the long-term period from 1875 to 2005 in the Czech Republic, central Europe. We analyzed nest altitude during years of founding of the nest, temperature, land use variables and types of nests (natural vs. human provided nest pads). Consistent with findings from previous studies we predicted a temporal increase in the altitude of white stork nests. Surprisingly, we found that the altitude of nests was decreasing, despite an increase in local mean spring temperatures. The altitude of nests was higher when the proportion of arable land, water areas and developed land was lower and when the proportion of grass and forest cover was greater. The decrease in altitude was significant in natural nests (built by storks) but non-significant in nests on nest platforms (built by humans). Thus, human agricultural activities might potentially override the opposing effects of global climate change on animal altitudinal distribution shifts.
On the X-ray spectrum of Kepler's supernova remnant

We have devised a method to do nonequilibrium ionization calculations on the results of two-dimensional hydrodynamical simulations, based on the algorithm of Hughes & Helfand (1985). We have calculated the ionization structure and X-ray emission for a two-dimensional numerical hydrodynamical simulation for the remnant of Kepler's supernova (SN); the hydrodynamical model was presented in a previous paper. In this model, the progenitor of Kepler's SN is assumed to have been a massive runaway star ejected from the Galactic plane. In its red supergiant stage, its dense stellar wind was distorted and compressed into a bow shock by the ram pressure of the tenuous interstellar medium. The subsequent interaction of the supernova ejecta with this asymmetric circumstellar matter produced a strongly asymmetric supernova remnant (SNR). In this paper, we present calculated X-ray spectra for this hydrodynamical model. A comparison with observations implies a moderate overabundance of Fe in Kepler's SNR (only 50% larger than its cosmic value), in contrast to a large (6 to 15) Fe overabundance derived previously. However, we confirm earlier conclusions that Si and S abundances are 2 to 3 times solar. These modest enhancements of Si, S, and Fe may be attributed either to heavy-element enriched SN ejecta or to the initial chemical abundances of the SN progenitor, which originated in the metal-rich inner Galaxy. The comparison of our models with the observed spectra confirm theoretical predictions that moderate electron heating occurs at strong collisionless shock fronts, with the implied electron/mean temperature ratio of approximately 0.5.
Almost Sure Decay Stability of the Backward Euler-Maruyama Scheme for Stochastic Differential Equations with Unbounded Delay

This paper deals with analytical and numerical stability properties of highly nonlinear stochastic differential equations (SDEs) with unbounded delay. Sufficient conditions for almost sure decay stability of previous system, almost sure decay stability of the backward Euler-Maruyama (BEM) methods are investigated. In \cite{Wu2010} and \cite{Mao2011}, the authors consider one-side linear growth condition and sufficient small step size. In this paper, we consider the monotone condition, which is weaker than one-side linear growth condition. And we only need a very weak restriction of the step size. Different from \cite{Szpruch2010}, Szpruch and Mao consider the asymptotic stability of the numerical approximate. In this paper we consider the almost sure decay stability of the numerical solution. This improves the existing results greatly.
Nonlinear effects in the ionosphere

The review is based in a report presented by the author at the RAS Physical Sciences Division's session in honor of Vitaly L Ginzburg's 90th birthday. It examines the current status of theoretical and experimental research on nonlinear phenomena arising when a powerful radio wave propagates in the ionosphere. The focus is on the modification of the ionosphere under the resonance excitation of natural plasma oscillations by radio waves. The upper-hybrid resonance gives rise to strong upper- and lower-hybrid plasma waves; excites strongly elongated ionospheric irregularities, and induces artificial ionospheric radio emission. Nonlinear processes are found to undergo complete transformation near double resonances, when the upper-hybrid frequency is close to a multiple of the electron gyromagnetic frequency. In the neighborhood of the Langmuir resonance, intense plasma waves and ion-sound waves are excited, electrons are effectively accelerated, and an artificial glow of the ionosphere appears.
A versatile spectrometer system for scanning Auger microscopy

An electron spectrometer system is described with some illustrative spectra. The system combines the requirements of scanning Auger microscopy with those of high resolution spectroscopy. The spectrometer is a concentric hemispherical analyser with a four-element input lens and can be operated with a high signal sensitivity, low energy resolution (Ca 7eV window), with 0.1 sr angle or with a high resolution and reduced sensitivity.
Are female workers more productive than male workers? An empirical study in Bangladesh

Job satisfaction is one of the most heavily researched employee attitudes over the last 50 years. Pleasing employees by appealing to their intrinsic and extrinsic needs is essential for obtaining maximum contribution of employees towards organisational objectives. To investigate gender differences on job satisfaction and are female workers are more productive than male worker, we have distributed 450 questionnaires among the respondents, 256 were returned, which shows a response rate of 56.7%. Data analysis tests were carried out by using statistical package for social sciences (SPSS) 20.0 version for Windows. Multivariate logistic regression analysis was used to find answers for the research questions. The findings of the Logit models indicate that female were significantly more satisfied than men and female workers performance is better than male worker.
Stabilized Sieve Sampling: A Point-Estimator Analysis

A modification of sieve sampling is proposed that returns a constant sample size. It is a scheme that selects line items with probability proportional to size (PPS) and nearly without replacement. An unbiased estimator of the total error amount is presented and its variance derived. Conditions under which the scheme is more efficient than sieve sampling and than PPS with replacement sampling are given.
STABILITY AND VIBRATION ANALYSIS OF NON-PRISMATIC THIN-WALLED COMPOSITE SPATIAL MEMBERS OF GENERIC SECTION

This paper presents a detailed treatment of the formulation of static, bucking and vibration analysis of non-prismatic thin-walled composite spatial members of generic section. The theory is limited to small strains, moderate deflections and small rotations. The torsional shear strain on the middle surface of the beam wall is zero for an open contour while it corresponds to constant shear flow for a closed contour. Rigorous expressions for strains based on membrane theory of shells are obtained through which the effect of nonlinear tapering is considered. Solutions for classical buckling and vibration analysis by the finite element method are discussed. Numerical integration by using Gaussian quadrature on the cross-sections for the computation of sectorial properties and stress resultants and over the length for the computation of flexural, geometric and mass matrices is suggested. Some examples are solved and critical bucking loads, natural frequencies and the corresponding buckled and mode shapes are obtained by the Jacobi iteration procedure.
Epidemic spreading in community networks

Social networks have the structure of communities. To understand how the community structure affects epidemic spreading, we present a simplified model of community network, and investigate the epidemic propagation in this model. We find that, compared to the random network, the community network has a broader degree distribution, a smaller threshold of epidemic outbreak, and more prevalence to keep the outbreak endemic. The formulae of epidemic threshold are given and confirmed by numerical simulations.
Scintillation parameters for 49 pulsars

We report on multi-epoch, multifrequency observations of 64 pulsars with high spectral and time resolution. Scintillation parameters were obtained for 49 pulsars, including 13 millisecond pulsars. Scintillation speeds were derived for all 49, which doubles the number of pulsars with speeds measured in this way. There is excellent agreement between the scintillation speed and proper motion for the millisecond pulsars in our sample using the simple assumption of a mid-placed scattering screen. This indicates that the scaleheight of scattering electrons is similar to that of the dispersing electrons. In addition, we present observations of the Vela pulsar at 14 and 23 GHz, and show that the scintillation bandwidth scales as ν3. 93 over a factor of 100 in observing frequency. We show that for PSR J0742−2822, and perhaps PSR J0837−4135, the Gum nebula is responsible for the high level of turbulence along their lines of sight, contrary to previous indications. There is a significant correlation between the scintillation speeds and the product of the pulsar's period and period derivative for the ‘normal’ pulsars. However, we believe this to be caused by selection effects both in pulsar detection experiments and in the choice of pulsars used in scintillation studies.