Web-based service of a visualization package “Amira” for the geosciences

Amira is a powerful three-dimensional visualization package that has been employed recently by the science and engineering communities to gain insight into their data. We discuss a new paradigm for the use of Amira in the Earth sciences that relies on the client-server paradigm. We have developed a module called WEB-IS2, which provides web-based access to Amira. This tool allows Earth scientists to manipulate Amira controls remotely and to analyze, render and view large datasets through the Internet without regard for time or location. This could have important ramifications for GRID computing.     

Interactive Statistical Analysis of Complex Mantle Flows with the Web

Up to now, all of the figures in mantle convection literature have been presented in a static manner, where the fields at one scale are shown on a printed page . This is no longer possible with the spatial resolution increasing at an ever rising clip and the appearance of the issue of multi-scale structures. Because of the onslaught of data-flooding and the growing complexity of strongly time-varying physical fields from compressible mantle convection, such as the adiabaticity, and other thermo dynamical heating functions, we can no longer afford to display and look at the results in the same static way as in a book. We have developed a new approach for interrogating data coming out from numerical simulations. This is based on an interactive two-dimensional map which is used over the WEB with a client-server paradigm. We have applied this to investigate mantle convection flows in both two-and three-dimensional situations. The distributions of thermal anomalies found are no longer Gaussian but sometimes have long tails, especially near the edges of plume heads. The same is also found for the distribution of mechanical heating, which can be quite skewed. Our experiences with this new interactive mode of data-query have shown both the educational and scientific importance of using the world wide web media to quiz handily the data taken from large-scale numerical simulations.     

Revealing the Nature of Contemporary Tourism Research: Extracting Common Subject Areas through Bibliographic Coupling

This study aims at identifying recent subject areas and citation patterns of tourism research by applying a bibliometric tool to analyze over 2000 publications since 2008 from 10 tourism journals. Twelve subject areas were identified, and interesting citation patterns were revealed. From this analysis, the tourism research was found to be quite dynamic but at the same time very much focused on marketing and management aspects. This article contributes to ongoing efforts to reveal the nature of tourism research and its knowledge bases by applying the methodology of bibliographic coupling. Copyright © 2014 John Wiley & Sons, Ltd.     

Pricing Asian Options and Equity-Indexed Annuities with Regime Switching by the Trinomial Tree Method

Abstract

Equity-indexed annuities (EIAs) provide investors with a minimum rate of return and at the same time the opportunity of gaining a profit that is linked to the performance of an equity index. These properties make EIAs a popular product in the market. For modeling the equity index process and calculating the price of EIAs, as the maturity of EIAs usually is long, it is more reasonable to assume that the interest rate and the volatility of the equity index are stochastic processes. One simple way is to apply the regime-switching model, which allows these parameters depending on the market situation. However, the valuation of derivatives in such models is challenging, especially for the strong path-dependent options such as Asian options. A trinomial tree model is introduced to provide an efficient way to solve this problem. The valuation of Asian options is studied and extended to Asian-option-related EIAs.     

THE SUITABILITY OF A GREATER CHINA CURRENCY UNION

Abstract. The study assesses the level of integration among the three Greater China economies (China, Hong Kong and Taiwan) and examines the suitability of a Greater China currency union. The three economies already have extensive trade and investment linkages. Our analyses show that they share common long‐run and short‐run cyclical variations. We also estimate the output costs of relinquishing policy autonomy to form a currency union. The estimated output losses, which depend on, e.g., the method used to generate shock estimates, seem to be moderate and are likely to be less than the efficient gains derived from a currency union.     

新世纪高校图书采访工作探讨

本文从若干方向较详实地论述了新世纪高校图书采访工作的方法以及培养采访人才的途径.     

Visualization and Analysis of Mixing Dynamical Properties in Convecting Systems with Different Rheologies

We analyzed and compared the mixing properties of 2-D mantle convection models. Two rheologically different models, Newtonian and non-Newtonian (power-law), were considered with both the line and field methods. The line method is based on monitoring of passive particles joined into lines, while the field method relies on the advection of a passive scalar field. Both visual and quantitative estimates revealed that the efficiency of the Newtonian mixing is greater than the non-Newtonian. A heterogeneity placed in the non-Newtonian convection forms horizontal structures, which may persist for at least 1 Ga on the upper-mantle scale. In addition, the non-Newtonian medium reveals a lesser amount of stretching of the lines than the Newtonian material. The rate of the Newtonian stretching fits well with an exponential dependence with time, while the non-Newtonian rheology shows the stretching rate close to a power-law dependence with time. In the Newtonian medium the heterogeneity is reorganized into two unstable vertical columns, while the non-Newtonian mixing favors horizontal structures. In the latter case, these structures are sufficiently stable in both the temporal and spatial planes to explain the mantle geochemical and geophysical heterogeneities. Due to the non-linear character of power-law rheology, the non-Newtonian medium offers a “natural” scale-dependent resistance to deformation, which prevents efficient mixing at the intermediate length scales.     

Visualization of multi-scale dynamics of hydrous cold plumes at subduction zones

Recent increases in the computational power of high-performance computing systems have led to a large gap between the high-resolution runs of numerical simulations—typically approaching 50–100 million tracers and 1–5 million grid points in two dimensions—and the modest resolution of 1–2 million pixels for conventional display devices. This technical problem is further compounded by the variety of fields produced by numerical simulations and the limited bandwidth available through the Internet in the course of collaborative ventures. We have developed a visualization system using the paradigm of web-based inquiry to address these mounting problems. We have employed, as a case study, a problem involving two-dimensional multi-scale dynamics of hydrous cold plumes at subduction zones. A Lagrangian marker method, in which the number of markers varies dynamically, is used to delineate the many different fields, such as temperature, viscosity, strain, and chemical composition. We found commercially available software to be insufficient for our visualization needs and so we were driven to develop a new set of tools tailored to high-resolution, multi-aspect, multi-scale simulations, and adaptable to many other applications in which large datasets involving tens of millions of tracers with many different fields are prevalent. In order to address this gap in visualization techniques, we have developed solutions for remote visualization and for local visualization. Our remote visualization solution is a web-based, zoomable image service (WEB-IS) that requires minimal bandwidth while allowing the user to explore our data through time, across many thermo–physical properties, and through different spatial scales. For local visualization, we found it optimal to use bandwidth-intensive, high-resolution display walls for performing parallel visualization in order to best comprehend the causal and temporal relationships between the multiple physical and chemical properties in a simulation.     

Dual aspects of mantle convection through time: Changes in global upper mantle temperature,Earth’s rotation,and global plate motion acceleration induced by mantle avalanches

We use modern and novel techniques to study the problems associated with detection and analysis of multitudinous seismic events, which form the background for isolated great earthquakes. This new approach involves multivariate analysis of low and large magnitude events recorded in space over a couple of centuries in time. We propose here the deployment of the clustering scheme both for extracting small local structures and large-scale trends in synthetic data obtained from four numerically simulated models with: uniform properties (U), a Parkfield-type asperity (A), fractal brittle properties (F), and multi-size-heterogeneity fault zone (M). The mutual nearest neighbor (mnn) clustering scheme allows for extraction of multi-resolutional seismic anomalies in both the spatio-temporal and multi-dimensional feature space. We demonstrate that the large earthquakes are correlated with a certain pathway of smaller events. Visualization of the anomalies by using a recently introduced visualization package Amira reveals clearly the spatio-temporal relationships between clusters of small, medium and large earthquakes, indicating significant stress relaxation across the entire fault region. We demonstrate that this mnn scheme can extract distinct clusters of the smallest events, which precede and follow a singularly large magnitude earthquake. These clusters form larger spatio-temporal structures comprising a series of large earthquakes. The link between the large and medium magnitude events is not so clearly understood. Short-ranged correlations are dominated by strong spatio-temporal anomalies, thus reflecting the global seismic properties of the entire fault zone.