Search Results

Stage and Scream: The Influence of Traditional Japanese Theater, Culture, and Aesthetics on Japan's Cinema of the Fantastic

Description: Although widely viewed in the West, Japanese films are often misunderstood, as they are built on cultural, theatrical, and aesthetic traditions entirely foreign to Western audiences. Particularly in regards to Japan's "fantastic" cinema - including giant monster pictures, ghost stories, and "J-Horror" films - what is often perceived as "cheap" or "cheesy" is merely an expression of these unique cultural roots. By observing and exploring such cultural artifacts as kabuki, noh, and bunraku - the traditional theatrical forms of Japan - long-standing literary traditions, deeply embedded philosophical beliefs, and even more recent developments such as the controversial dance form butoh, these films, including Gojira (1954), Daimajin (1966), Kwaidan (1964), Onibaba (1964), Testuo the Iron Man (1989), and Ju-On (2002), can be placed in their proper perspective, leading to a reevaluation of their worth not merely as commercial products, but as uniquely Japanese expressions of that society's unique place in world culture.
Date: May 2011
Creator: Petty, John E.
Partner: UNT Libraries

[Couple in Bamboo]

Description: Photograph of Ray and Georgia Gough in Japan. The couple is visible in the center of the frame posing on a stone pathway. The pathway runs through the middle of a bamboo grove.
Date: unknown
Creator: Gough, Ray
Partner: UNT College of Visual Arts + Design

OECD Global Forum on Sustainable Development: Emissions Trading: Concerted Action on Tradeable Emissions Permits Country Forum

Description: The aim of the Forum was to bring representatives from OECD and non-OECD country governments together with representatives from the research community, to identify and discuss key policy issues relating to GHG emissions trading and other project based mechanisms for GHG emission reduction, such as Joint Implementation and the Clean Development Mechanism. These mechanisms are of significant interest to both Economies in Transition and developing countries. The scope of the Forum also covered experiences with the use of emission trading in other environmental policy applications, such as reducing conventional air pollutants.
Date: March 2003
Creator: Ogushi, Takuya & Kure, Seiki
Partner: UNT Libraries

Annual Report on the Environment and the Sound Material-Cycle Society in Japan 2007

Description: The annual report summarized the FY2006 status of the environment and the establishment of a sound material-cycle Society in Japan. It provides an overview of Global Warming and the technologies for mitigating Global Warming. The report also describes the government's role in environmental conservation, and the formation of a sound material-cycle society.
Date: 2007
Creator: Japan. Kankyōsho
Partner: UNT Libraries

Palau's fall would weaken Japs.

Description: Black & white map of the southern Pacific Ocean, showing the north of Australia, parts of China, Korea, and French-Indo-China, New Guinea, the Philippines, Japan, and several small islands. An inset text box in the lower left corner titled "Pacific Progress" describes the completed and future goals of the U.S. armed forces toward defeating Japan. In the upper right corner is an inset map of Palau.
Date: 1944
Creator: O'Donohoe, J.
Partner: UNT Libraries Government Documents Department

A Comparative Analysis of Minoru Miki's Time For Marimba and Concerto for Marimba and Orchestra

Description: Minoru Miki's first two marimba compositions, Time for Marimba (1968) and Concerto for Marimba and Orchestra (1969) were composed at a revolutionary time-period for the marimba. Due to unique and innovative compositional techniques, Miki helped establish the marimba as a true concert instrument capable of performing music of the highest quality. As a pioneer in composing for marimba literature, Miki was able to capture the true essence of the marimba; a timeless quality that has helped Time for Marimba remain a part of the standard solo repertoire for the past forty years. The purpose of this study is to analyze and compare Minoru Miki's compositions, Time for Marimba and Concerto for Marimba and Orchestra. Composed within a year of each other, these works possess similar compositional techniques, and rhythmic and thematic relationships. This thesis includes a formal analysis and detailed comparisons of compositional techniques used in both works. Performance considerations, a brief biographical sketch of Miki and historical significance of Time for Marimba and Concerto for Marimba and Orchestra are also included.
Date: December 2008
Creator: Zator, Brian Edward
Partner: UNT Libraries

Numerical investigation for the impact of CO2 geologic sequestration on regional groundwater flow

Description: Large-scale storage of carbon dioxide in saline aquifers may cause considerable pressure perturbation and brine migration in deep rock formations, which may have a significant influence on the regional groundwater system. With the help of parallel computing techniques, we conducted a comprehensive, large-scale numerical simulation of CO{sub 2} geologic storage that predicts not only CO{sub 2} migration, but also its impact on regional groundwater flow. As a case study, a hypothetical industrial-scale CO{sub 2} injection in Tokyo Bay, which is surrounded by the most heavily industrialized area in Japan, was considered, and the impact of CO{sub 2} injection on near-surface aquifers was investigated, assuming relatively high seal-layer permeability (higher than 10 microdarcy). A regional hydrogeological model with an area of about 60 km x 70 km around Tokyo Bay was discretized into about 10 million gridblocks. To solve the high-resolution model efficiently, we used a parallelized multiphase flow simulator TOUGH2-MP/ECO2N on a world-class high performance supercomputer in Japan, the Earth Simulator. In this simulation, CO{sub 2} was injected into a storage aquifer at about 1 km depth under Tokyo Bay from 10 wells, at a total rate of 10 million tons/year for 100 years. Through the model, we can examine regional groundwater pressure buildup and groundwater migration to the land surface. The results suggest that even if containment of CO{sub 2} plume is ensured, pressure buildup on the order of a few bars can occur in the shallow confined aquifers over extensive regions, including urban inlands.
Date: April 15, 2009
Creator: Yamamoto, H.; Zhang, K.; Karasaki, K.; Marui, A.; Uehara, H. & Nishikawa, N.
Partner: UNT Libraries Government Documents Department

Changes of Well Characteristics in the Hatchobaru Geothermal Field (Japan) by Exploitation of Unit No. 2

Description: The reservoir exploitation for Unit No.2 of the Hatchobaru Power Station accelerated the decline of power output of Unit No.1. For the purpose of understanding the mechanism of this output decline, review of existing data, additional well characteristics tests, well loggings and tracer tests were carried out. The results showed that several production wells for Unit No. 1 significantly reduced their productivity due to the inflow of reinjected waste water and due to pressure interference with production wells for Unit No. 2.
Date: January 1, 1995
Creator: Mimura, T.; Oishi, K.; Ogata, Y.; Tokita, H.; Tsuru, Y. & Matsuda, K.
Partner: UNT Libraries Government Documents Department

Activation Measurements for Thermal Neutrons, U.S. Measurements of 36Cl in Mineral Samples from Hiroshima and Nagasaki; and Measurement of 63 Ni in Copper Samples From Hiroshima by Accelerator Mass Spectrometry

Description: The present paper presents the {sup 36}Cl measurement effort in the US. A large number of {sup 36}Cl measurements have been made in both granite and concrete samples obtained from various locations and distances in Hiroshima and Nagasaki. These measurements employed accelerator mass spectrometry (AMS) to quantify the number of atoms of {sup 36}Cl per atom of total Cl in the sample. Results from these measurements are presented here and discussed in the context of the DS02 dosimetry reevaluation effort for Hiroshima and Nagasaki atomic-bomb survivors. The production of {sup 36}Cl by bomb neutrons in mineral samples from Hiroshima and Nagasaki was primarily via the reaction {sup 35}Cl(n,{gamma}){sup 36}Cl. This reaction has a substantial thermal neutron cross-section (43.6 b at 0.025 eV) and the product has a long half-life (301,000 y). hence, it is well suited for neutron-activation detection in Hiroshima and Nagasaki using AMS more than 50 years after the bombings. A less important reaction for bomb neutrons, {sup 39}K(n,{alpha}){sup 36}Cl, typically produces less than 10% of the {sup 36}Cl in mineral samples such as granite and concrete, which contain {approx} 2% potassium. In 1988, only a year after the publication of the DS86 final report (Roesch 1987), it was demonstrated experimentally that {sup 36}Cl measured using AMS should be able to detect the thermal neutron fluences at the large distances most relevant to the A-bomb survivor dosimetry. Subsequent measurements in mineral samples from both Hiroshima and Nagasaki validated the experimental findings. The potential utility of {sup 36}Cl as a thermal neutron detector in Hiroshima was first presented by Haberstock et al. who employed the Munich AMS facility to measure {sup 36}Cl/Cl ratios in a gravestone from near the hypocenter. That work subsequently resulted in an expanded {sup 36}Cl effort in Germany that paralleled the US work. More recently, ...
Date: January 14, 2005
Creator: Straume, Tore; Marchetti, Alfredo A.; Egbert, Stephen D.; Roberts, James A.; Men, Ping; Fujita, Shoichiro et al.
Partner: UNT Libraries Government Documents Department

Analysis of pressure transient data from the Sumikawa geothermal field

Description: The permeability structure of the Sumikawa geothermal field in northern Japan has been the subject of an extensive pressure-transient testing investigation since 1986. In this paper, various pertinent data sets are presented and analyzed, including results showing reservoir heterogeneity (i.e. boundary) effects and apparent double porosity behavior. Interference tests between wells SB-3 and SD-2 (both of which have feedpoints in dacitic layers in the ''marine-volcanic complex'' formation) were carried out during 1990. The results have been interpreted to indicate the presence of a moderately high permeability ({approx} 4 darcy-meters) layer with two impermeable boundaries intersecting at a right angle. The 1988 pressure buildup data for well SN-7D are also explained by assuming two impermeable boundaries in a high transmissivity reservoir within the deep ''granodiorite'' formation. Interference tests between wells S-4 and KY-1 have suggested that a very permeable north-south channel is present in the ''altered andesite'' layer. Although the response was successfully interpreted using an ''anisotropic line-source model'' by Garg et al. (1991), a ''double porosity channel model'' seems to be particularly applicable for explaining both the short-term and long-term behavior observed in this series of tests.
Date: January 1, 1992
Creator: Ishido, T.; Kikuchi, T.; yano, Y.; Miyazaki, Y.; Nakao, S. & Hatakeyama, K.
Partner: UNT Libraries Government Documents Department

Evolution of neural networks for the prediction of hydraulic conductivity as a function of borehole geophysical logs: Shobasama site, Japan.

Description: This report describes the methodology and results of a project to develop a neural network for the prediction of the measured hydraulic conductivity or transmissivity in a series of boreholes at the Tono, Japan study site. Geophysical measurements were used as the input to EL feed-forward neural network. A simple genetic algorithm was used to evolve the architecture and parameters of the neural network in conjunction with an optimal subset of geophysical measurements for the prediction of hydraulic conductivity. The first attempt was focused on the estimation of the class of the hydraulic conductivity, high, medium or low, from the geophysical logs. This estimation was done while using the genetic algorithm to simultaneously determine which geophysical logs were the most important and optimizing the architecture of the neural network. Initial results showed that certain geophysical logs provided more information than others- most notably the 'short-normal', micro-resistivity, porosity and sonic logs provided the most information on hydraulic conductivity. The neural network produced excellent training results with accuracy of 90 percent or greater, but was unable to produce accurate predictions of the hydraulic conductivity class. The second attempt at prediction was done using a new methodology and a modified data set. The new methodology builds on the results of the first attempts at prediction by limiting the choices of geophysical logs to only those that provide significant information. Additionally, this second attempt uses a modified data set and predicts transmissivity instead of hydraulic conductivity. Results of these simulations indicate that the most informative geophysical measurements for the prediction of transmissivity are depth and sonic log. The long normal resistivity and self potential borehole logs are moderately informative. In addition, it was found that porosity and crack counts (clear, open, or hairline) do not inform predictions of hydraulic transmissivity.
Date: June 1, 2004
Creator: Reeves, Paul C. & McKenna, Sean Andrew
Partner: UNT Libraries Government Documents Department

An example uncertainty and sensitivity analysis at the Horonobe site for performance assessment calculations.

Description: Given pre-existing Groundwater Modeling System (GMS) models of the Horonobe Underground Research Laboratory (URL) at both the regional and site scales, this work performs an example uncertainty analysis for performance assessment (PA) applications. After a general overview of uncertainty and sensitivity analysis techniques, the existing GMS sitescale model is converted to a PA model of the steady-state conditions expected after URL closure. This is done to examine the impact of uncertainty in site-specific data in conjunction with conceptual model uncertainty regarding the location of the Oomagari Fault. In addition, a quantitative analysis of the ratio of dispersive to advective forces, the F-ratio, is performed for stochastic realizations of each conceptual model. All analyses indicate that accurate characterization of the Oomagari Fault with respect to both location and hydraulic conductivity is critical to PA calculations. This work defines and outlines typical uncertainty and sensitivity analysis procedures and demonstrates them with example PA calculations relevant to the Horonobe URL.
Date: August 1, 2004
Creator: James, Scott Carlton
Partner: UNT Libraries Government Documents Department

Summary report on transportation of nuclear fuel materials in Japan : transportation infrastructure, threats identified in open literature, and physical protection regulations.

Description: This report summarizes the results of three detailed studies of the physical protection systems for the protection of nuclear materials transport in Japan, with an emphasis on the transportation of mixed oxide fuel materials1. The Japanese infrastructure for transporting nuclear fuel materials is addressed in the first section. The second section of this report presents a summary of baseline data from the open literature on the threats of sabotage and theft during the transport of nuclear fuel materials in Japan. The third section summarizes a review of current International Atomic Energy Agency, Japanese and United States guidelines and regulations concerning the physical protection for the transportation of nuclear fuel materials.
Date: March 1, 2008
Creator: Cochran, John Russell; Ouchi, Yuichiro (Japan Atomic Energy Agency, Japan); Furaus, James Phillip & Marincel, Michelle K.
Partner: UNT Libraries Government Documents Department

Open literature review of threats including sabotage and theft of fissile material transport in Japan.

Description: This report is a review of open literature concerning threats including sabotage and theft related to fissile material transport in Japan. It is intended to aid Japanese officials in the development of a design basis threat. This threat includes the external threats of the terrorist, criminal, and extremist, and the insider threats of the disgruntled employee, the employee forced into cooperation via coercion, the psychotic employee, and the criminal employee. Examination of the external terrorist threat considers Japanese demographics, known terrorist groups in Japan, and the international relations of Japan. Demographically, Japan has a relatively homogenous population, both ethnically and religiously. Japan is a relatively peaceful nation, but its history illustrates that it is not immune to terrorism. It has a history of domestic terrorism and the open literature points to the Red Army, Aum Shinrikyo, Chukaku-Ha, and Seikijuku. Japan supports the United States in its war on terrorism and in Iraq, which may make Japan a target for both international and domestic terrorists. Crime appears to remain low in Japan; however sources note that the foreign crime rate is increasing as the number of foreign nationals in the country increases. Antinuclear groups' recent foci have been nuclear reprocessing technology, transportation of MOX fuel, and possible related nuclear proliferation issues. The insider threat is first defined by the threat of the disgruntled employee. This threat can be determined by studying the history of Japan's employment system, where Keiretsu have provided company stability and lifetime employment. Recent economic difficulties and an increase of corporate crime, due to sole reliability on the honor code, have begun to erode employee loyalty.
Date: June 1, 2005
Creator: Cochran, John Russell; Furaus, James Phillip & Marincel, Michelle K.
Partner: UNT Libraries Government Documents Department

PEP-II And KEKB Operational Status

Description: The present two B-Factories, PEP-II at SLAC in California and KEKB at KEK in Tsukuba, Japan, operate at the Upsilon 4S and have reached parameter levels unprecedented for e+e- colliders. They have provided very large data samples for their respective particle detectors, BaBar and BELLE. Luminosity has exceeded 1.5 x 10{sup 34}/cm{sup 2}/s. Beam currents have reached 2.5 A with 1600 positron bunches spaced by 4 nsec. Continuous injection with the detectors taking data has added significantly to data collection rates by about 40%. Bunch-by-bunch feedback systems damp strong longitudinal and transverse coupled bunch instabilities. The beam-beam interaction has allowed high tune shift levels even in the presence of parasitic crossing and crossing angle effects. Both B-Factory colliders have significant near term luminosity improvement programs.
Date: February 6, 2006
Creator: Seeman, J. & /SLAC
Partner: UNT Libraries Government Documents Department

De Novo Ultrascale Atomistic Simulations On High-End Parallel Supercomputers

Description: We present a de novo hierarchical simulation framework for first-principles based predictive simulations of materials and their validation on high-end parallel supercomputers and geographically distributed clusters. In this framework, high-end chemically reactive and non-reactive molecular dynamics (MD) simulations explore a wide solution space to discover microscopic mechanisms that govern macroscopic material properties, into which highly accurate quantum mechanical (QM) simulations are embedded to validate the discovered mechanisms and quantify the uncertainty of the solution. The framework includes an embedded divide-and-conquer (EDC) algorithmic framework for the design of linear-scaling simulation algorithms with minimal bandwidth complexity and tight error control. The EDC framework also enables adaptive hierarchical simulation with automated model transitioning assisted by graph-based event tracking. A tunable hierarchical cellular decomposition parallelization framework then maps the O(N) EDC algorithms onto Petaflops computers, while achieving performance tunability through a hierarchy of parameterized cell data/computation structures, as well as its implementation using hybrid Grid remote procedure call + message passing + threads programming. High-end computing platforms such as IBM BlueGene/L, SGI Altix 3000 and the NSF TeraGrid provide an excellent test grounds for the framework. On these platforms, we have achieved unprecedented scales of quantum-mechanically accurate and well validated, chemically reactive atomistic simulations--1.06 billion-atom fast reactive force-field MD and 11.8 million-atom (1.04 trillion grid points) quantum-mechanical MD in the framework of the EDC density functional theory on adaptive multigrids--in addition to 134 billion-atom non-reactive space-time multiresolution MD, with the parallel efficiency as high as 0.998 on 65,536 dual-processor BlueGene/L nodes. We have also achieved an automated execution of hierarchical QM/MD simulation on a Grid consisting of 6 supercomputer centers in the US and Japan (in total of 150 thousand processor-hours), in which the number of processors change dynamically on demand and resources are allocated and migrated dynamically in response to faults. Furthermore, performance ...
Date: September 4, 2006
Creator: Nakano, A; Kalia, R K; Nomura, K; Sharma, A; Vashishta, P; Shimojo, F et al.
Partner: UNT Libraries Government Documents Department

Renewable Energy Opportunities at the Kanto Installations, Japan

Description: This document provides an overview of renewable resource development potential at the U.S. Army installations in the Kanto region in Japan, which includes Camp Zama, Yokohama North Dock, Sagamihara Family Housing Area (SFHA), Sagami General Depot, and Akasaka Press Center. This effort focuses on grid-connected generation of electricity from renewable energy sources and also on ground source heat pumps for heating and cooling buildings. The effort was funded by the Huntsville Army Corps of Engineers, and includes the development of a methodology for renewable resource assessment at Army installations located on foreign soil. The methodology is documented in Renewable Energy Assessment Methodology for Japanese OCONUS Army Installations. The site visit to the Kanto installations took place on April 5 and 6, 2010. At the current time, there are some renewable technologies that show economic potential. Because of siting restrictions and the small size of these installations, development of most renewable energy technologies will likely be limited to Camp Zama. Project feasibility is based on installation-specific resource availability and energy costs and projections based on accepted life-cycle cost methods. Development of any renewable energy project will be challenging, as it will require investigation into existing contractual obligations, new contracts that could be developed, the legality of certain partnerships, and available financing avenues, which involves the U.S. Forces Japan (USFJ), the Government of Japan (GOJ), and a number of other parties on both sides. The Army will not be able to implement a project without involvement and approval from the other services and multiple levels of Japanese government. However, implementation of renewable energy projects could be an attractive method for GOJ to reduce greenhouse gas emissions and lower annual utility payments to USFJ. This report recommends projects to pursue and offers approaches to use. The most promising opportunities include waste-to-energy and ground ...
Date: September 24, 2010
Creator: Solana, Amy E.; Horner, Jacob A.; Russo, Bryan J.; Gorrissen, Willy J.; Kora, Angela R.; Weimar, Mark R. et al.
Partner: UNT Libraries Government Documents Department

In Situ Pu isotopic measurements using electromechanically cooled HPGe detectors at PFPF

Description: A high-resolution gamma ray spectroscopy (HRGS) system has been installed at the Advanced Material Accountancy Glovebox Assay (AMAGB) System so that neutron and gamma ray measurements can occur simultaneously on material transfer containers. This equipment was installed in August 2000 at the Plutonium Fucl Production Facility (PFPF) in Japan. It is anticipated that placing the HRG6 system at the neutron assay station will save a few person-days per IAEA inspection because it will no longer be necessary to take samples from the transfer container for isotopic analysis at another assay station. The HRGS system consists of a 25% relative efficiency coaxial detector with electromechanical cooling and digital signal processing. The digital spectrometer has the benefit of increasing throughput, improving energy resolution, and extending the lifetime of neutron damaged HPGe detectors as compared to analog spectrometers. The gamma-ray system is used to verify the Pu isotopic composition and {sup 241}Am concentration in transfer containers of MOX. The {sup 240}Pu{sub eff} action is calculated from the isotopic data and is used to convert the neutron assay data to total grams plutonium. The results of performance tests and calibration measurements using this system are reported in this paper.
Date: January 1, 2001
Creator: Wenz, T. R. (Tracy R.); Menlove, Howard O.; Maruyama, H. (Hajime); Fujiwara, S. (Shigeo) & Takahashi, S. (Saburo)
Partner: UNT Libraries Government Documents Department

Partnerships for Clean Development and Climate: Business andTechnology Cooperation Benefits

Description: Development and poverty eradication are urgent andoverriding goals internationally. The World Summit on SustainableDevelopment made clear the need for increased access to affordable,reliable and cleaner energy and the international community agreed in theDelhi Declaration on Climate Change and Sustainable Development on theimportance of the development agenda in considering any climate changeapproach. To this end, six countries (Australia, China, India, Japan,Republic of Korea and the United States) have come together to form theAsia Pacific Partnership in accordance with their respective nationalcircumstances, to develop, deploy and transfer cleaner, more efficienttechnologies and to meet national pollution reduction, energy securityand climate change concerns consistent with the principles of the U.N.Framework Convention on Climate Change (UNFCCC). The APP builds on thefoundation of existing bilateral and multilateral initiativescomplements.APP has established eight public-private sector Task Forcescovering: (1) cleaner fossil energy; (2) renewable energy and distributedgeneration; (3) power generation and transmission; (4) steel; (5)aluminium; (6) cement; (7) coal mining; and (8) buildings and appliances.As a priority, each Task Force will formulate detailed action plansoutlining both immediate and medium-term specific actions, includingpossible "flagship" projects and relevant indicators of progress by 31August 2006. The partnership will help the partners build human andinstitutional capacity to strengthen cooperative efforts, and will seekopportunities to engage the private sector. The APP organized An OutreachWorkshop: Business&Technology Cooperation Opportunities forIndustry on August 26, 2006, New Delhi. This paper was prepared toprovide background information for participants of the Conference. Ithighlights energy efficiency, renewable energy, and climate technologies,barriers, and partnerships that are being implemented in the US, Indiaand other selected countries. The paper discusses the lessons to belearned from these partnerships, and ways by which the APP could fostercooperation between India and the other member countries. It highlightsthe types of technologies that Indian public sector and private industrycould access from US national laboratories and also be able to ...
Date: August 22, 2006
Creator: Sathaye, Jayant A.; Price, Lynn; Kumar, Satish; de la Rue du Can,Stephane; Warfield, Corina & Padmanabhan, S.
Partner: UNT Libraries Government Documents Department

Prediction and prevention of silica scaling at low levels of oversaturation: Case studies, and calculations for Uenotai Geothermal Field, Akita Prefecture, Japan

Description: Production system design studies often include site-specific silica scaling field experiments, conducted because the onset and rate of scaling are believed difficult to predict, particularly at relatively low levels of oversaturation such as may exist in separators, flowlines, and injection wells. However, observed scaling occurrences (Cerro Prieto, Dixie Valley, Svartsengi, Otake, Hatchobaru, Milos, experimental work) actually conform fairly well to existing theory and rate equations. It should be possible to predict low level scaling with sufficient confidence for production and injection system design and, in cases where oversaturation is allowed, to design systems with foresight to suppress or manage the scale which develops. A promising suppression technology is fluid pH reduction by mixing with non-condensible gases and/or condensate. Calculations for injection lines at Uenotai geothermal field indicate molecular deposition at rates of 0.1 to 1 mm/yr, and some potential for particle deposition at points of turbulence, which can be suppressed by an order of magnitude with about 500 ppm CO{sub 2}. Further improvements of predictive technique will benefit from more uniformity in designing experiments, reporting results, and reporting measurements of scaling in actual production systems.
Date: January 1, 1991
Creator: Klein, Christopher W.; Iwata, Shun; Takeuchi, Rituo & Naka, Tohsaku
Partner: UNT Libraries Government Documents Department

Using ancillary information to improve hypocenter estimation: Bayesian single event location (BSEL)

Description: We have developed and tested an algorithm, Bayesian Single Event Location (BSEL), for estimating the location of a seismic event. The main driver for our research is the inadequate representation of ancillary information in the hypocenter estimation procedure. The added benefit is that we have also addressed instability issues often encountered with historical NLR solvers (e.g., non-convergence or seismically infeasible results). BSEL differs from established nonlinear regression techniques by using a Bayesian prior probability density function (prior PDF) to incorporate ancillary physical basis constraints about event location. P-wave arrival times from seismic events are used in the development. Depth, a focus of this paper, may be modeled with a prior PDF (potentially skewed) that captures physical basis bounds from surface wave observations. This PDF is constructed from a Rayleigh wave depth excitation eigenfunction that is based on the observed minimum period from a spectrogram analysis and estimated near-source elastic parameters. For example, if the surface wave is an Rg phase, it potentially provides a strong constraint for depth, which has important implications for remote monitoring of nuclear explosions. The proposed Bayesian algorithm is illustrated with events that demonstrate its congruity with established hypocenter estimation methods and its application potential. The BSEL method is applied to three events: (1) A shallow Mw 4 earthquake that occurred near Bardwell, KY on June 6, 2003, (2) the Mw 5.6 earthquake of July 26, 2005 that occurred near Dillon, MT, and (3) a deep Mw 5.7 earthquake that occurred off the coast of Japan on April 22, 1980. A strong Rg was observed from the Bardwell, KY earthquake that places very strong constraints on depth and origin time. No Rg was observed for the Dillon, MT earthquake, but we used the minimum observed period of a Rayleigh wave (7 seconds) to reduce the depth ...
Date: January 1, 2008
Creator: Anderson, Dale N
Partner: UNT Libraries Government Documents Department