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The effect of FPU architecture on a dynamic precision algorithm for the solution of differential equations
Solution of lnitial Value Problems (IVPs) is an important application in scientific computing. Methods for solving these problems use techniques for reducing the error and increasing the speed of the computation. This paper introduces a class of algorithms which dynamically reconfigure their operating parameters to reduce the computation time. By dynamically varying the precision of the arithmetic being performed, it is possible to obtain dramatic speedups on certain architectures when solving IVPs. This paper illustrates how various architectures impact on a dynamic precision version of the Runge-Kutta-Fehlberg algorithm. It is shown that a speedup of over 30 percent is possible for both massively parallel processors and vector supercomputers
X-Ray Emission-Line Profile Modeling Of O Stars: Fitting A Spherically Symmetric Analytic Wind-Shock Model To The Chandra Spectrum Of Zeta Puppis
X-ray emission-line profiles provide the most direct insight into the dynamics and spatial distribution of the hot, X-ray-emitting plasma above the surfaces of OB stars. The O supergiant zeta Puppis shows broad, blueshifted, and asymmetric line profiles, generally consistent with the wind-shock picture of OB star X-ray production. We model the profiles of eight lines in the Chandra HETGS spectrum of this prototypical hot star. The fitted lines indicate that the plasma is distributed throughout the wind starting close to the photosphere, that there is significantly less attenuation of the X-rays by the overlying wind than is generally supposed, and that there is not a strong trend in wind absorption with wavelength
Field Comparisons of Hydraulic Conductivity Methods and Drainage Envelope Hydraulic Characteristics
South Dakota is presently planning for the irrigation of approximately one-half million acres of land in the proposed Oahe Unit located in the north central part of the state. The main body of land in the Oahe Unit is the Lake Plain area which was once the lakebed of post-glacial Lake Dakota. Approximately one-fifth of the total cost of the project will be for drainage systems. The Bureau of Reclamation is responsible for the design of the Oahe project. They are presently using a transient drainage spacing equation developed by Glover in the design of the drainage system. The use of this design equation requires the evaluation of two soil parameters; saturated soil hydraulic conductivity and drainable porosity. The auger hole method is usually used to determine the saturated soil hydraulic conductivity under saturated soil conditions. The Bureau uses a point field method called the pump-in method to estimate the saturated hydraulic conductivity of the soil under unsaturated conditions. The accuracy of the pump-in method as compared to the auger hole method has been questioned. Therefore, the Bureau of Reclamation and the South Dakota Agricultural Experiment Station decided to compare these two methods on an experimental plot at the James Valley Research and Extension Center which is within the bounds of the Oahe project. This experimental plot area contains a subsurface drainage system which was installed in 1967. Since the soils of the plot area are not completely uniform, the drain line discharges reflect an average of the soils and envelope hydraulic characteristics. An open trench construction technique was used to install the drain lines which resulted in a disturbed soil profile above the drain lines. Drainage design equations in contrast assume a homogeneous soil which means the disturbed trench soil has the same drainage characteristics as the undisturbed soil. Therefore, an investigation of the disturbed soil hydraulic conductivity was initiated to determine the effect of the trench backfill material on drain line discharges
Insight Dialogue: Investigation of a Relational Meditation Practice
Contemporary psychology has shown a strong and growing interest in Buddhist psychological (BP) theory and practice, which has informed numerous clinical interventions, influenced psychotherapeutic approach, and increasingly been the subject of empirical investigation (Goyal et al., 2014, Keng, Smoski, & Robins, 2011, Neff & Germer, 2012). This widespread adoption and adaptation of BP concepts, including mindfulness, self-compassion, and compassion, has primarily focused on the development of individual skills and internal change. However, despite the critical role relationship plays in human development, in the experience of distress, and in healing, the development of these skills and qualities in an explicitly relational context has not been investigated. Insight Dialogue (ID) is a meditation practice that brings into relationship BP concepts and practices typically constrained to individual silent practice. The purpose of the current study is: 1) to assess if participation in a ID meditation retreat results in the development of the skills and qualities of mindfulness, self- compassion, compassion, and well-being; 2) to examine the relationships between these variables; and 3) to provide an increased understanding of how the relational context affected the cultivation of these concepts. The sample consisted of men and women (N=100; Mean age = 55) who were recruited from five ID retreats conducted across North America. Data were collected immediately before (T1) and after (T2) the ID retreat. Repeated measures analyses were conducted to assess for main effects. A simple moderation analyses and a path analysis were used to test for indirect effects and to assess the utility of the hypothesized models. Several hypotheses were supported, including significant increases in mindfulness, self-compassion, and well-being. Additionally, after completion of an ID retreat, self-compassion was found to significantly moderate the relationship between mindfulness and well-being (95% [CI 0.239, 0.474]). The implications, limitations of these results and the current study, as well as directions for future research are discussed
Distribution of the Blue-Spotted Salamander Ambystoma laterale Hallowell in Minnesota
This paper brings together the known locality records of Ambystoma laterale in Minnesota. Recent nomenclature changes involving this salamander, its favored habitat and possible range extensions also are included
Democracy in Crisis: Corruption, Media, and Power in Turkey
In November 2013, a Freedom House delegation traveled to Turkey to meet with journalists, NGOs, business leaders, and senior government officials about the deteriorating state of media freedom in the country. The delegation's objective, and the plan for this report, was to investigate reports of government efforts to pressure and intimidate journalists and of overly close relationships between media owners and government, which, along with bad laws and overly aggressive prosecutors, have muzzled objective reporting in Turkey.Since November, events in Turkey have taken a severe turn for the worse. The police raids that revealed a corruption scandal on December 17, and the allegations of massive bidrigging and money laundering by people at the highest levels of the government, have sparked a frantic crackdown by the ruling Justice and Development (AK) Party. More journalists have been fired for speaking out. Hundreds of police officers and prosecutors have been fired or relocated across the country. Amendments to the new Internet regulation law proposed by the government would make it possible for officials to block websites without court orders. The government is also threatening the separation of powers by putting the judiciary, including criminal investigations, under direct control of the Ministry of Justice. The crisis of democracy in Turkey is not a future problem -- it is right here, right now.This report on the media recognizes that what is happening in Turkey is bigger than one institution and part of a long history that continues to shape current events. The media in Turkey have always been close to the state; as recently as 1997, large media organizations were co-opted by the military to subvert a democratically elected government. The AK Party was formed in the wake of those events. But even as it has tamed the military, the AKP has been unable to resist the temptations of authoritarianism embedded in the state the military helped create. Over the past seven years, the government has increasingly employed a variety of strong-arm tactics to suppress the media's proper role as a check on power. Some of the most disturbing efforts include the following:Intimidation: Prime Minister Recep Tayyip Erdo?an frequently attacks journalists by name after they write critical commentary. In several well-known cases, like those of Hasan Cemal and Nuray Mert, journalists have lost their jobs after these public attacks. Sympathetic courts hand out convictions in defamation cases for criticism.Mass firings: At least 59 journalists were fired or forced out in retaliation for their coverage of last summer's Gezi Park protests. The December corruption scandal has produced another string of firings of prominent columnists.Buying off or forcing out media moguls: Holding companies sympathetic to the government receive billions of dollars in government contracts, often through government bodies housed in the prime minister's office. Companies with media outlets critical of the government have been targets of tax investigations, forced to pay large fines, and likely disadvantaged in public tenders.Wiretapping: The National Security Organization has wiretapped journalists covering national security stories, using false names on the warrants in order to avoid judicial scrutiny.Imprisonment: Dozens of journalists remain imprisoned under broadly defined antiterrorism laws. A majority of those in prison are Kurds, and some analysts believe the government is using them as bargaining chips in negotiations with the Kurdish PKKThese tactics are unacceptable in a democracy. They deny Turkish citizens full access to information and constrain a healthy political debate. Journalists and government officials alike acknowledge that reporters and news organizations have practiced self-censorship to avoid angering the government, and especially Prime Minister Erdogan.The intentional weakening of Turkey's democratic institutions, including attempts to bully and censor Turkey's media, should and must be a matter of deep concern for the United States and the European Union. As the AKParty's internal coalition has grown more fragile, Erdogan has used his leverage over the media to push issues of public morality and religion and to squelch public debate of the accountability of his government. The result is an increasingly polarized political arena and society.Freedom House calls on the government of Turkey to recognize that in a democracy, a free press and other independent institutions play a very important role. There are clear and concrete steps the Turkish government must take to end the intimidation and corruption of Turkey's media. Chief among these are the following:Cease threats against journalists.Repeal the criminal defamation law and overly broad antiterrorism and "criminal organization" laws that have been used to jail dozens of journalists.Comply with European and international standards in procurement practices in order to reduce the incentive for media owners to curry favor by distorting the news. Turkish media owners themselves must make a commitment to support changes in procurement practices if they are to win back the trust of Turkey's citizens.Although building a resilient democracy is fundamentally up to Turkish citizens, the international community cannot afford to be bystanders. The European Union and the OSCE have raised strong concerns about government pressure on Turkey's media, and the EU's warnings against governmental overreach have been pointed. Unfortunately, the same cannot be said for the United States. The Obama administration has been far too slow to realize the seriousness of the threat to Turkey's democracy. U.S. criticism of the Turkish government's recent actions has come from the State Department spokesperson and White House press secretary, not from the high-ranking officials who need to be engaged in responding to a crisis of this scale. Where European governments and institutions have been specifically and publicly engaged with the government over the crisis, the Obama administration has avoided the difficult issues. It is time to speak frankly and with seriousness about the growing threat to democracy in Turkey, and to place freedom of expression and democracy at the center of the policy relationship
Representing and Utilizing DDI in Relational Databases
This document is primarily intended for implementers of DDI-based metadata stores who are considering different technical options for housing and managing their metadata. The Data Documentation Initiative (DDI) metadata specification is expressed in the form of XML schema. With version 3, the DDI specification has become quite complex, including 21 namespaces and 846 elements. Organizations employing DDI, or considering doing so, may want to 1. store and manage the metadata elements in relational databases, for reasons of integration with existing systems, familiarity with the concepts of relational databases (such as Structured Query Language), systems performance, and/or other reasons; 2. select only the subset of the available DDI metadata elements that is of utility to their work, and have the flexibility of capturing metadata they need that would not fit into the DDI model. This paper discusses advantages and disadvantages of the relational database approach to managing DDI. It also describes methods for modeling DDI in relational databases and for formally defining subsets of DDI to employ in this environment.
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