Model Selection Criteria for Segmented Time Series from a Bayesian Approach to Information Compression

The principle that the simplest model capable of describing observed phenomena should also correspond to the best description has long been a guiding rule of inference. In this paper a Bayesian approach to formally implementing this principle is employed to develop model selection criteria for detecting structural change in financial and economic time series. Model selection criteria which allow for multiple structural breaks and which seek the optimal model order and parameter choices within regimes are derived. Comparative simulations against other popular information based model selection criteria are performed. Application of the derived criteria are also made to example financial and economic time series.Complexity theory; segmentation; break points; change points; model selection; model choice.

Wavelet Analysis and Lognormal Distributions in GRBs

A wavelet analysis has been performed on 80 intense gamma-ray bursts GRBs) from the BATSE 3B catalog with durations longer than 2 seconds. The wavelet analysis applied novel features developed for edge detection in image processing and this filtering process was used to extract a fit to the irregular GRB profile from the background. A straightforward algorithm was subsequently used to identify statistically significant peaks in this profile. The areas and FWHM of 270 peaks that were characterised as isolated were found to be consistent with lognormal distributions. The distribution of time intervals between peak maxima for all 963 identified peaks in the GRBs is also presented.Comment: 5 pages, 4 figure

Drone Technology for Monitoring and Mapping in the Grasslands of Eastern Montana

The Nature Conservancy in Montana has been working to protect wildlife habitat and enhance conservation in the Northern Great Plains for several decades.  The foundation of our work has been the Matador Grassbank in south Phillips County. Through the grassbank, ranchers implement conservation practices on their home ranches in exchange for discounted grazing on the Conservancy’s Matador Ranch. One of the conservation practices is the retention of black-tailed prairie dog towns. The southern portion of Phillips County supports among the most acres and largest prairie dog towns in the state. The prairie dog towns in this region of Montana support species of high conservation concern, including two black-footed ferret reintroduction sites, the largest population of mountain plovers, and large numbers of burrowing owls. Discounts for retaining prairie dog towns on grassbank ranches is tiered, based on the size of the town and potential for supporting species of concern. However, precisely mapping towns is challenging when using handheld GPS units and ATV’s to traverse the perimeters. Currently, The Nature Conservancy is using drone technology to create more precise and detailed maps. Drones yield detailed imagery which can be incorporated into a GIS, allowing precise mapping of town boundaries. Using drones will enable ranchers and the Conservancy to better understand the expansion or contraction of towns over time. The Matador ranch successfully implemented drone technology as a tool for more efficient and accurate monitoring, and plans to continue incorporating its use in all aspects of conservation and management

SP-100 reactor with Brayton conversion for lunar surface applications

Examined here is the potential for integrating Brayton-cycle power conversion with the SP-100 reactor for lunar surface power system applications. Two designs were characterized and modeled. The first design integrates a 100-kWe SP-100 Brayton power system with a lunar lander. This system is intended to meet early lunar mission power needs while minimizing on-site installation requirements. Man-rated radiation protection is provided by an integral multilayer, cylindrical lithium hydride/tungsten (LiH/W) shield encircling the reactor vessel. Design emphasis is on ease of deployment, safety, and reliability, while utilizing relatively near-term technology. The second design combines Brayton conversion with the SP-100 reactor in a erectable 550-kWe powerplant concept intended to satisfy later-phase lunar base power requirements. This system capitalizes on experience gained from operating the initial 100-kWe module and incorporates some technology improvements. For this system, the reactor is emplaced in a lunar regolith excavation to provide man-rated shielding, and the Brayton engines and radiators are mounted on the lunar surface and extend radially from the central reactor. Design emphasis is on performance, safety, long life, and operational flexibility

La mujer en la iglesia : cuestión de solidaridad

Después de dos años de haber "participado en el diálogo con un grupo de mujeres, unas de la clase trabajadora, otras de la clase media", Brian Lennon, Gerry O'Hanlon, Bill Toner y Frank Sammon, jesuitas irlandeses, presentan algunos puntos de vista aportados por estas mujeres y dan una respuesta inicial en el documento La mujer en la iglesia. Cuestión de solidaridad. Este texto va acompañado del decreto de la Congregación General 34 de la Compañía de Jesús sobre la Compañía y la situación de la mujer en la iglesia y en la sociedad. Ambos testimonios nos invitan a la reflexión en lo que se refiere a nuestras actitudes y pautas de comportamiento hacia la mujer, creatura, como el hombre, a imagen y semejanza de Dios. Esta publicación busca avanzar en la comprensión de asunto tan vital y demandante.ITESO, A.C

Localisation of gamma-ray interaction points in thick monolithic CeBr3 and LaBr3:Ce scintillators

Localisation of gamma-ray interaction points in monolithic scintillator crystals can simplify the design and improve the performance of a future Compton telescope for gamma-ray astronomy. In this paper we compare the position resolution of three monolithic scintillators: a 28x28x20 mm3 (length x breadth x thickness) LaBr3:Ce crystal, a 25x25x20 mm3 CeBr3 crystal and a 25x25x10 mm3 CeBr3 crystal. Each crystal was encapsulated and coupled to an array of 4x4 silicon photomultipliers through an optical window. The measurements were conducted using 81 keV and 356 keV gamma-rays from a collimated 133Ba source. The 3D position reconstruction of interaction points was performed using artificial neural networks trained with experimental data. Although the position resolution was significantly better for the thinner crystal, the 20 mm thick CeBr3 crystal showed an acceptable resolution of about 5.4 mm FWHM for the x and y coordinates, and 7.8 mm FWHM for the z-coordinate (crystal depth) at 356 keV. These values were obtained from the full position scans of the crystal sides. The position resolution of the LaBr3:Ce crystal was found to be considerably worse, presumably due to the highly diffusive optical in- terface between the crystal and the optical window of the enclosure. The energy resolution (FWHM) measured for 662 keV gamma-rays was 4.0% for LaBr3:Ce and 5.5% for CeBr3. The same crystals equipped with a PMT (Hamamatsu R6322-100) gave an energy resolution of 3.0% and 4.7%, respectively

The Grizzly, April 23, 1982

Recurring Thefts Plague New Men\u27s Dorm • Final Forum Discusses Use of Photography in Space • Too Much Grass on Campus? • Letters to the Editor • Congress Puts Hold on Financial Aid Cuts • Reagan\u27s Change of Style • Vanities Well Received by Community • Hooters Reggae Keeps UC Jumping • UC Baseball Splits With Widener • Men\u27s Tennis Top Widener • Bear Blades Finish Season Strong • Women\u27s Tennis Head to MACs • Women\u27s Track Club Earns First Place • Temple Dumps Women\u27s Lacrosse • Men\u27s Lacrosse is on Trackhttps://digitalcommons.ursinus.edu/grizzlynews/1079/thumbnail.jp

The Grizzly, February 13, 1981

Water Crisis Worsens: TCE Also a Problem • Pett Leaving Economics Department • Mobley Breaks Basketball Record • News Briefs: Meistersingers concert in Oreland; Ursinus professor published • Departmental Focus: English Department; History Department • Orientation Committee Applications Being Taken • 1981 Fraternity Pledge Classes • Music News • Female Artists Topic of Forum • Coffeehouse: A Folk Touch • Candidates for USGA Offices • Women\u27s B-Ball Undefeated 9 Straight • Tight Season Ahead for Intramural B-Ball • Badminton Team Playin\u27 Tough • Hoopsters Claim Two More Victims • Grizzly Grapplers Mark at 7-4-1 • Aquabears Dunk Foes: Swimmers Living Up to .500 Goalhttps://digitalcommons.ursinus.edu/grizzlynews/1052/thumbnail.jp

The Grizzly, November 21, 1980

Dean of Students\u27 Office Releases Vandalism Figures • Maintenance Working To Conserve Energy • Weight Room Relocated In Helfferich • College Union Attempts World\u27s Largest Molecule • Ursinus News In Brief: Espadas to speak today in Illinois; Maintenance planting new trees; Placement interviews coming soon • Rassias Method Explored for Languages • Journalism To Be Added To Curriculum • Medical Ethics Course Offered • Phil. & Rel. Dept. Lecture On Judaism • College To Host 43rd Messiah Performance • Foghat and Outlaws Perform for \u27Serious Rockers\u27 • Forum On Radiation Draws Mixed Views • Art Exhibit On Display In Wismer • Open House Planned By Astronomy Club • A Look At This Year\u27s Basketball Season • Cross Country To Compete In Nationals This Weekend • Gridders Lose Early Lead to Tie Gettysburghttps://digitalcommons.ursinus.edu/grizzlynews/1048/thumbnail.jp