One-way Methods Research Articles

Exploring Communication Approaches in Medication Consultations for Generation Z: a Cross-Sectional Descriptive Study of Two-Way and One-Way Methods

Exploring Communication Approaches in Medication Consultations for Generation Z: a Cross-Sectional Descriptive Study of Two-Way and One-Way Methods

Improving students' critical thinking ability through the inquiry learning model and discovery learning

The issue underlying this research is the low critical thinking skills of students in SMAN 3 Ciamis which is caused by the learning process which still uses traditional, one-way methods and does not develop students' thinking skills. The purpose of this study was to determine students' critical thinking skills after applying Inquiry Leaning, Discovery Learning and Conventional methods. The method used is quasi-experimental with a Counterbalance research design. The instrument in the research was multiple choice complex questions that measured students' critical thinking skills. The results of analysis and testing using One Way Anova show that there are differences in students' critical thinking abilities from each treatment carried out in each class with different methods so that the hypothesis proposed can be accepted. Judging from the results of the acquisition of the average value (mean) of students' critical thinking skills in each study, it shows that classes using the Inquiry Leaning model are always higher than the Discovery Learning and conventional models. The conclusion of this study is that the Inquiry Learning model is more effective in improving critical thinking skills compared to Discovery Learning and conventional learning models.

Amplitude-Preserved Wave Equation: An Example to Image the Gas Hydrate System

Natural gas hydrate is an important energy source. Therefore, it is extremely important to provide a clear imaging profile to determine its distribution for energy exploration. In view of the problems existing in conventional migration methods, e.g., the limited imaging angles, we proposed to utilize an amplitude-preserved one-way wave equation migration based on matrix decomposition to deal with primary and multiple waves. With respect to seismic data gathered at the Chilean continental margin, a conventional processing flow to obtain seismic records with a high signal-to-noise ratio is introduced. Then, the imaging results of the conventional and amplitude-preserved one-way wave equation migration methods based on primary waves are compared, to demonstrate the necessity of implementing amplitude-preserving migration. Moreover, a simple two-layer model is imaged by using primary and multiple waves, which proves the superiority of multiple waves in imaging compared with primary waves and lays the foundation for further application. For the real data, the imaging sections of primary and multiple waves are compared. We found that multiple waves are able to provide a wider imaging illumination while primary waves fail to illuminate, especially for the imaging of bottom simulating reflections (BSRs), because multiple waves have a longer travelling path and carry more information. By imaging the actual seismic data, we can make a conclusion that the imaging result generated by multiple waves can be viewed as a supplementary for the imaging result of primary waves, and it has some guiding values for further hydrate and in general shallow gas exploration.

Application of Spectral Method for Vibration-Induced High-Cycle Fatigue Evaluation of an High-Pressure Turbine Blade

Abstract A method of fluid–structure interaction coupling is implemented for a forced-response, vibration-induced fatigue life estimation of a high-pressure turbine blade. Two simulations approaches; a two-way (fully coupled) and one-way (uncoupled) methods are implemented to investigate the influence of fluid–solid coupling on a turbine blade structural response. The fatigue analysis is performed using the frequency domain spectral moments estimated from the response power spectral density (PSD) of the two simulation cases. The method is demonstrated in relation to the time-domain method of the rainflow cycle counting method with mean stress correction. Correspondingly, the mean stress and multi-axiality effects are also accounted for in the frequency domain spectral approach. In this case, a multiplication coefficient is derived based on the Morrow equation, while the case of multi-axiality is based on a criterion which reduces the triaxial stress state to an equivalent uniaxial stress using the critical plane assumption. The analyses show that while the vibration-induced stress histories of both simulation approaches are stationary, they violate the assumption of normality of the frequency domain approaches. The stress history profile of both processes can be described as platykurtic with the distributions having less mass near its mean and in the tail region, as compared to a Gaussian distribution with an equal standard deviation. The fully coupled method is right leaning with positive skewness while the uncoupled approach is left leaning with negative skewness. The directional orientation of the principal axes was also analyzed based on the Euler angle estimation. Although noticeable differences were found in the peak distribution of the normal stresses for both methods, the predicted Euler angle orientations were consistent in both cases, depicting a similar orientation of the critical plane during a crack initiation and propagation process. Finally, the fatigue life estimation was shown to be conservative in the fully coupled solution approach.

Superwide-angle seismic migration by including the back-scattered wave through domain decomposition and biaxial parabolic approximation

Using ideas from computational electromagnetics and the basic procedure from the domain decomposition method, we present a biaxial parabolic approximation method for enlarging the angle domain in which the parabolic approximation to the acoustic wave equation is multiple applied and that can be used for migrating data with super-wide angles. Mathematically, the biaxial approximation is a special case of the multiaxial parabolic approximation, and thus can be straightforwardly extended to multiaxial approximations. In detail, we first divide the subsurface into several fan-shaped subdomains and use the axis of each subdomain as the local wave propagation direction. Then, we make a parabolic approximation to the wave equation in each subdomain with respect to the corresponding symmetry axis and compute the forward-propagating wave alternately using a high-order parabolic approximated wave equation in two subdomains. Finally, we use the computed forward-propagating wave as the boundary condition for calculating the back-scattered wave and Green's function by applying the thin slab approximation. Compared with most one-way methods, the proposed method can deal with the strong velocity contrast in the horizontal direction at a large scattering angles. Moreover, compared with certain full-wave methods that have been published in recent years, the proposed method is considerably more efficient and sacrifices only a little in terms of accuracy. Numerical results from comparisons with models of different complexities demonstrate that our method is cost-effective and has considerable potential for use in seismic modeling and imaging.

Изменчивость интерлейкинов при когнитивной нагрузке у больных с хронической ишемией мозга

Neuroimmune interactions represent a highly dynamic mechanism for the regulation of cognitive function in chronic cerebral ischemia (CCI). The aim of this study was to investigate changes in salivary proinflammatory cytokines IL1β and IL6 and anti-inflammatory IL10 in patients with CCI (mean age 65.4 ± 9.1 years) before and after cognitive tests. After cognitive tests, the levels of salivary IL1β and IL6 were significantly elevated by 101.6 ± 19.1 pg/ml (n = 74) and 32.8 ± 6.1 pg/ml (n = 74), respectively. Using one-way ANOVA ana non-parametric statistical methods, we were able to demonstrate associations between changes in salivary interleukins and cognitive performance. In the group of patients with a significant increase in IL1β, some cognitive parameters were lower than in the group with negative or zero dynamics of this cytokine: the patients made more mistakes in the subtraction test (F = 11.5; n = 63; p = 0.001) and performed worse in the Luria test (F = 6.8; n = 65; p = 0.01). For IL6, Spearman’s rank correlation coefficient for the number of mistakes in the subtraction test was positive and differed significantly from 0 (R = 0.26; n = 62; p = 0.042). The group with positive IL10 dynamics performed better in N-back test (F = 5.2; n = 67; p = 0.03) and made fewer mistakes in the subtraction test (F = 6.8; n = 63; p = 0.01) in comparison with patients who demonstrated negative IL10 dynamics. Good performance in other cognitive tests was not correlated with interleukin dynamics. The article also discusses possible mechanisms underlying interleukin effects on cognitive function in patients with CCI and applications of the obtained data.

Tri-Clustering Based Exploration of Temporal Resolution Impacts on Spatio-Temporal Clusters in Geo-Referenced Time Series

Unprecedented amounts of spatio-temporal data instigates an urgent need for patterns exploration in it. Clustering analysis is useful in extracting patterns from big data by grouping similar data elements into clusters. Compared with one-way clustering and co-clustering methods, tri-clustering methods are more capable of exploring complex patterns. However, the explored patterns or clusters could be different due to varying temporal resolutions of input data. This study presents a tri-clustering based method to explore the impacts of different temporal resolutions on spatio-temporal clusters identified in geo-referenced time series (GTS), one type of spatio-temporal data. Dutch daily temperature data at 28 stations over 20 years was used to illustrate this study. The temperature data at daily, monthly, and yearly resolutions were subjected to the Bregman cube average tri-clustering algorithm with I-divergence (BCAT_I) to detect spatio-temporal clusters, which were then compared in terms of patterns exhibited, compositions, and changed elements. Results confirm the temporal resolution impacts on the spatio-temporal clusters identified in the Dutch temperature data: most compositions of clusters are varying when changing the temporal resolutions of input data in the GTS. Nevertheless, there is almost no change of elements in certain clusters (12 stations in the northeast of the country; years 1996, 2010) at all temporal resolutions, suggesting them as the “true” clusters in the case study dataset.

Imaging of primaries and multiples using a dual-sensor towed streamer

Multiple reflections are commonly treated as noise in one-way imaging methods. High effort is put into research and data processing worldwide in an effort to suppress this source of noise. In a new perspective multiples are treated as valuable imaging information. Based on dual-sensor towed streamer measurement, we decompose the wavefield and apply up/down imaging of primary and multiple reflections. This approach is tested using shallow water synthetic data and finally applied on dual-sensor field data.

3D superwide-angle one-way propagator and its application in seismic modeling and imaging

Traditional one-way wave-equation based propagators have been widely used in past decades. Comparing to two-way propagators, one-way methods have higher efficiency and lower memory demands. These two features are especially important in solving large-scale 3D problems. However, regular one-way propagators cannot simulate waves that propagate in large angles within 90° because of their inherent wide angle limitation. Traditional one-way can only propagate along the determined direction (e.g., z-direction), so simulation of turning waves is beyond the ability of one-way methods. We develop 3D superwide-angle one-way propagator to overcome angle limitation and to simulate turning waves with superwide-angle propagation angle (>90°) for modeling and imaging complex geological structures. Wavefields propagating along vertical and horizontal directions are combined using typical stacking scheme. A weight function related to the propagation angle is used for combining and updating wavefields in each propagating step. In the implementation, we use graphics processing units (GPU) to accelerate the process. Typical workflow is designed to exploit the advantages of GPU architecture. Numerical examples show that the method achieves higher accuracy in modeling and imaging steep structures than regular one-way propagators. Actually, superwide-angle one-way propagator can be applied based on any one-way method to improve the effects of seismic modeling and imaging.

Does Entrepreneurship Education Affect Entrepreneurship Level?

Article History: Received 05.07.2015 Received in revised form 03.01.2016 Accepted 24.01.2016 Available online 22.03.2016 The aim of entrepreneurship education is to enable the individuals to be aware of their entrepreneur features, to encourage them to set their own business, to increase employment and to decrease unemployment. One of the most important factors for the development of entrepreneurship is to make the education to this end prevalent and to develop the entrepreneur features of individuals. The purpose of this study is to determine the entrepreneurship levels of Bachelor students studying at different departments at Usak University regarding that they have had education in entrepreneurship and put forward suggestions. In the field study carried out for this aim, 254 Bachelor students were included in the sample group. Questionnaires were given to junior and senior students studying at five different departments: Public Administration, Finance, Business Administration, Chemical Engineering and Mechanical Engineering. For the evaluation of the data obtained, descriptive statistics, standard deviation, mean, lost data analysis, confirmation factor analysis, reliability, independent t-test and one-way variance analysis methods were employed. According to the findings of the study, it has been observed that the results of confirmation factor analysis are one factor and the factor loads of 36-item model has varied between 0.36-0.74. Besides, the internal consistency index of the scale, as a result of the reliability analysis of the 36 items, has been found 0.930. In addition, it has shown that the model has acceptable fit indices and that the data cohere the model (χ2=1.388, df=594, p<.001; RMSEA=0.073, % 90 GA=0.068-0.078; GFI= 0.96; AGFI=0.95; CFI=0.96; NNFI=0.95). Statistically no meaningful differences have been seen between the entrepreneurship levels of students and their departments, grade, fathers’ jobs, and whether they have taken the course or not. However, there are statistically meaningful differences between entrepreneurship levels and gender and the students who have answered “I can set my own business”. The entrepreneurship levels of male students compared to females and those who answered the statement “I can set my own business” Yes compared to those who answered No have been seen to be higher. © 2016 IOJES. All rights reserved

Factors Affecting Indoor Radon Concentrations of Greek Dwellings through Multivariate Statistics - First Approach

A large scale nationwide radon survey was conducted in Greek dwellings between 1994 and 2000. Twelve hundred passive CR-39 detectors were distributed and collected along with 963 filled in questionnaires. These were rechecked during 2012-13 to evaluate factors that potentially affect indoor radon concentrations, namely the factors (i) area (environment), (ii) building level-floor, (iii) ground type, (iv) basement, (v) building type, (vi) construction year, (vii) building walls contact, (viii) wall materials and (ix) floor materials. The questionnaires were prepared by the research team according to international standards. One-way and multivariate statistical methods were applied for the analysis, in specific (I) Linear Regression Analysis, (II) One way or multiway ANOVA, (III) General MANOVA, (IV) Stepwise Regression Analysis and (V) Principal Components Analysis. The results revealed that approximately 0.1% of the dwellings exhibited outlier radon concentrations. Noteworthy statistical correlations were detected between the measured mean annual indoor radon concentration levels and the factors (ii) (building level-floor) and (viii) (wall materials). Weak evidence was provided for the corresponding correlation with the factors (v) (building type) and (vii) (building walls contact). Minor was the association with the factors (iv) (construction year) and (ix) (floor materials). Significant differences were detected in the results of the applied statistical methods.

Using Strategic Communication for Nation-Building in Contemporary Spain: The Basque Case

This article analyzes the use of strategic communication for nation-building purposes in the case of regions, or the so-called “stateless nations” of contemporary Spain. It describes the case of the Basque Country region where successive nationalist governments over the last 30 years have used soft and hard power methods for this purpose. The soft power methods have consisted fundamentally of the use of mass media campaigns and funded institutional publicity to generate a climate of opinion that opposes Basque identity and Spanish identity. Other soft power methods have involved the promotion of Basque culture, beliefs, and values through mostly public diplomacy efforts (which also had an impact among internal audiences). Soft power approaches have resulted in a positive climate of opinion concerning an inclusive (not ethnic) Basque identity without political connotations. Nevertheless, this positive outcome has been contradicted by other hard power approaches such as the implementation of coercive linguistic laws and a level of passivity towards terrorism. Far from reinforcing each other, the intensive use of one-way communication and hard power methods seems to have created a dissonance between Basque identity and Basque nationalism.

Wave-equation angle-based illumination weighting for optimized subsalt images

A methodology has been developed for improving seismic depth images generated in areas of complex structure, such as subsalt. The main goal of the wave-equation angle-based illumination workflow is to calculate a set of illumination weight gathers and apply them to migrated field angle gathers. To obtain meaningful illumination weight gathers, it is important to use the field-acquisition geometry information, migration velocity models, and interpreted horizons. The workflow is model based and requires horizons conformable to real structure, preferably picked on the field seismic depth images. The workflow is implemented using one-way and two-way wave-equation methods and is tested on narrow-azimuth towed-streamer (NATS) and merged NATS with wide-azimuth towed-streamer (XWATS) data sets. The method weights down poorly illuminated areas while preserving strongly illuminated areas, which is opposite to the compensation methods. As a result, an overall improvement in seismic depth images can be observed, especially in subsalt areas. The impact of the workflow on improving well-tie estimation at the Thunder Horse subsalt development in the Gulf of Mexico is demonstrated.

One-way/one-return boundary-element method and salt internal multiples

Surface-related multiples or internal multiples can produce artifacts in migrated images using one-way wave-equation methods. Salt-body-related internal-multiple removal remains a challenging problem for this approach. To investigate the effects of salt-body-related internal multiples on subsalt imaging, the boundary-element method is implemented in a one-way/one-return scheme to separate the primary transmission/reflection arrivals at the salt boundaries from the internal multiples. Numerical results demonstrate that the proposed method is effective for modeling primary transmission/reflection arrivals through/from irregular interfaces between strong-velocity-contrast media. Internal multiples are obtained through straight subtraction of primary reflection arrivals from full reflected-wave data. The image from prestack depth migration of these pure internal multiples using one-way propagators is compatible with some strong artifacts in the subsalt region from migration of full-wave data using the same one-way propagators. Results suggest that a significant part of artifacts in the subsalt region in the prestack image for the 2D SEG-EAGE salt model using one-way propagators might be caused by salt internal multiples.

Seismic imaging using lateral adaptive windows

One-way wavefield extrapolation methods are used routinely in 3D depth migration algorithms for seismic data. Due to their efficient computer implementations, such one-way methods have become increasingly popular and a wide variety of methods have been introduced. In salt provinces, the migration algorithms must be able to handle large velocity contrasts because the velocities in salt are generally much higher than in the surrounding sediments. This can be a challenge for one-way wavefield extrapolation methods. We present a depth migration method using one-way propagators within lateral windows for handling the large velocity contrasts associated with salt-sediment interfaces. Using adaptive windowing, we can handle large perturbations locally in a similar manner as the beamlet propagator, thus limiting the impact of the errors on the global wavefield. We demonstrate the performance of our method by applying it to synthetic data from the 2D SEG/EAGE [Formula: see text] salt model and an offshore real data example.

A review of time and frequency transfer methods

I will discuss the three general methods that are commonly used to transmit time and frequency information: one-way methods, which measure or model the path delay using ancillary data, two-way methods, which depend on the symmetry of the delays in opposite directions along the same path, and common view, in which several stations receive data from a common source over paths whose delays are approximately equal. I will describe the advantages and limitations of the different methods including uncertainty estimates for systems that are based on them.

2.5D SH Wave Propagation in Heterogeneous Crustal Wave Guides Using the Phase Screen Method

Abstract One-way approximations for regional phases slice the half-space crustal wave guide into a number of slabs perpendicular to the propagation direction; the Moho discontinuity can be easily treated as a perturbation from the crustal background. The advantage of one-way propagation methods is their great saving of computing time and memory compared to full-waveform numerical methods, especially for 3D simulations. In this article, we present general 2.5D SH formulas for the thin-slab method and a generalized screen propagator (GSP) for simulating SH wave propagation in the heterogeneous half-space crustal wave guide. Comparisons of numerical results with a finite-difference (FD) algorithm for a standard flat crustal model show excellent agreement, demonstrating the validity and accuracy of the 2.5DGSP for the half-space problem. We then compare the curves of energy attenuation calculated by the 2D and 2.5D formulas. The comparison shows that the energy attenuation of the 2.5D case is about 1.5–3 times greater than that of the 2D case when the trapped mode is formed. The SH screen propagator is also used to simulate two laterally unvarying (in the y direction) crustal models, showing the path effects on regional wave propagation.

Finite difference 3D common-shot migration of data from the West Delta area of the Gulf of Mexico

The advent of the network, or “cluster,” of modern personal computers has enabled prestack 3D “wave equation” methods, such as common-shot migration, to become practical alternatives to standard Kirchhoff depth migration. Clusters have overcome hardware limitations (cost-effective memory and speed) that previously limited the widespread use of these wave equation algorithms. Prestack Kirchhoff migration is efficient and easily adapts to various data acquisition geometries, while its steep-dip and high-resolution imaging capabilities are unparalleled. Traveltime calculations, typically by ray tracing, are fundamental to conventional Kirchhoff migration. However, propagating wavefronts become complicated when traveling through complex geology; for example, a simple spherical wave propagating near its source eventually separates into several (or many) distinct “branches” as the wave encounters large lateral velocity variations. Computing 3D traveltime fields that faithfully represent such wave propagation and actually using these in 3D Kirchhoff migration is difficult and computationally expensive. Conventional Kirchhoff migration instead uses simplified, single-valued traveltime fields produced by criteria such as first arrival or maximum energy. Where several raypaths encounter a grid node, for example, the maximum-energy criterion selects the traveltime from the raypath with largest amplitude. The single-valued traveltime approximation may be poor in complex geology, where the traveltime fields really are multibranched or multivalued. Prestack wave equation imaging, on the other hand, such as finite difference common-shot migration, uses numerical modeling of the one-way wave equation instead of ray tracing. These wave equation methods can be more accurate than ray methods for modeling wave propagation in complex media. The result can be a superior image in areas of complex geology, such as beneath salt bodies. The most serious limitation of these one-way wave equation methods is that they are dip-limited relative to Kirchhoff methods, especially for strong lateral velocity variations. Most of today's prestack wave equation methods use accurate “dual-domain” techniques …

Local orthogonal transformation and one-way methods for acoustic waveguides

A numerical method is developed for solving the two-dimensional Helmholtz equation in a region bounded by a flat top and a curved bottom. A local orthogonal transformation is first used to flatten the curved bottom of the waveguide. The one-way re-formulation based on the Dirichlet-to-Neumann map is then used to reduce the boundary value problem to an initial value problem. Numerical implementation of the resulting operator Riccati equation uses a large range step method for discretizing the range variable and a truncated local eigenfunction expansion for approximating the operators. This method is particularly useful for solving long range wave propagation problems in slowly varying waveguides.

Seismic Wave Propagation and Scattering in Heterogeneous Crustal Waveguides Using Screen Propagators: I SH Waves

The great advantages of one-way propagation methods, such as the gen- eralized screen propagators (GSP) method, are the fast speed of computation, often several orders of magnitude faster than the full-wave finite difference and finite element methods, and the huge savings in internal memory. In this article, a half- space GSP is formulated for the SH half-space problem. Two versions of the half- space GSP are derived: the wide-angle pseudo-screen and the phase-screen. The Moho discontinuity is treated as parameter perturbations from the crustal back- ground. The validity and limitations of this treatment are discussed. It is shown that half-space screen propagators can accurately propagate guided crustal waves that are composed of small-angle waves with respect to the horizontal direction. Comparisons of numerical results with a wavenumber integration method for flat crustal models and a finite difference algorithm for heterogeneous models show excellent agree- ments. For a model with propagation distance of 250 km, dominant frequency at 0.5 Hz, the GSP method is about 300 times faster than a finite difference algorithm with a similar accuracy. These comparisons demonstrate the accuracy and efficiency of the method. We apply our method to simulate regional wave propagation in different types of complex crustal waveguides including those with small-scale random het- erogeneities. The influence of these heterogeneities on Lg amplitude attenuation and Lg coda formation is significant.