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The use of Volunteered Geographic Information (VGI) in collecting, sharing and disseminating geospatially referenced information on the Web is increasingly common. The potentials of this localized and collective information have been seen to complement the maintenance process of authoritative mapping data sources and in realizing the development of Digital Earth. The main barrier to the use of this data in supporting this bottom up approach is the credibility (trust), completeness, accuracy, and quality of both the data input and outputs generated. The only feasible approach to assess these data is by relying on an automated process. This paper describes a conceptual model of indicators (parameters) and practical approaches to automated assess the credibility of information contributed through the VGI including map mashups, Geo Web and crowd – sourced based applications. There are two main components proposed to be assessed in the conceptual model – metadata and data. The metadata component comprises the indicator of the hosting (websites) and the sources of data / information. The data component comprises the indicators to assess absolute and relative data positioning, attribute, thematic, temporal and geometric correctness and consistency. This paper suggests approaches to assess the components. To assess the metadata component, automated text categorization using supervised machine learning is proposed. To assess the correctness and consistency in the data component, we suggest a matching validation approach using the current emerging technologies from Linked Data infrastructures and using third party reviews validation. This study contributes to the research domain that focuses on the credibility, trust and quality issues of data contributed by web citizen providers.

This paper compares two Java-based persistent storage mechanisms: a commercially available object-oriented database (OODB) system1 and the persistent storage tool PJama [1] on the basis of their suitability for implementing the index component of an experimental World Wide Web search engine called WWLib-TNG. Persistence is provided to the builder component of the search engine, which constructs a catalogue of Web pages. The searcher component of the engine searches the catalogue. The implementation of the builder using PJama and using an OODB were compared with respect to time taken to construct a catalogue, efficient use of disk space and scalability. The implementations of the searcher were compared on response time and scalability. The comparison showed that for this application PJama performs better than the OODB. Compared with the OODB, PJama gave 300% better build performance and was more scalable.

PowerPoint from the presentation given by Mike Blouin (Pomona '08) on July 26, 2007. This was the seventh presentation out of eight taking place during the Sustainability Presentations Day at Harvey Mudd College.

AC susceptibility measurements as a function of field amplitude Hac and of frequency show a strong field dependence for a set of synthetic titanomagnetites (Fe3−xTixO4) and for certain basalts from the SOH-1 Hawaiian drill hole and from Iceland. In-phase susceptibility is constant below fields of about 10–100 A/m, and then increases by as much as a factor of two as Hac is increased to 2000 A/m. Both the initial field-independent susceptibilities and the field-dependence of susceptibility are systematically related to composition: initial susceptibility is 3 SI for a single-crystal sphere of TM0 (x=0) and decreases with increasing titanium content; field-dependence is nearly zero for TM0 and increases systematically to a maximum near TM60 (x=0.6). This field dependence can in some cases be mistaken for frequency dependence, and lead to incorrect interpretations of magnetic grain size and composition when titanomagnetite is present.

Titanium substitution has a significant effect on the temperature dependence (5–300 K) of low-temperature saturation remanence and of initial susceptibility in synthetic and natural titanomagnetite (Fe3−xTixO4, 0≤x 0.4, and electronic and lattice relaxation phenomena over the entire titanomagnetite compositional range. These features produce diagnostic magnetic behavior useful for titanomagnetite identification in natural samples. Moreover, the apparent similarities between the thermal decay of low-temperature remanence of titanomagnetite with pyrrhotite, pure magnetite, and superparamagnetic phases can lead to complications in interpreting low-temperature remanence data when titanomagnetite is present.

Background MobileGIS refers to the use of geographic data in the field on mobile devices like networked personal digital assistant (PDA). The main components for MobileGIS are global positioning system (GPS), mobile device i.e. mobile phone, and communication network with GIS acting as the backbone. Map generalization is the process by which small scale maps are to be derived from large scale maps. This requires the appropriate use of map generalization operations to be performed subsequent to scale reduction to reduce the graphic conflict.

Early-age bridge-deck cracking is a major problem affecting the durability of U.S. bridges. Many factors can cause early-age bridge-deck cracking including change in temperature, hydration, plastic shrinkage, autogenous shrinkage, and drying shrinkage. The presence of cracking may increase the effect of freeze and thaw cycles and may lead to corrosion of reinforcement, which may result in deterioration of the entire bridge. It is crucial to investigate the issue of early-age cracking in bridge decks to provide solutions to improve the safety of U.S. bridges. This research examines the use of different sealing materials to seal the developed cracks while the performance criteria can be achieved. An analytical study was performed to study the importance of major parameters that may affect the transverse deck cracking, such as concrete strength, shrinkage, thermal effect, load patterns, load magnitude, span length, number of spans, and continuity. A finite-element model was developed to investigate the factors affecting tensile stresses and crack tendency. Also, a tool was developed to predict the likelihood and initiation of early-age cracking in bridge decks. The outcomes of this study identify suitable sealant materials and identify a set of recommendations to limit the cracking problem and, hence, resulting in a longer service life to bridges.

A 500-800 km long segment of the Himalaya bordered by the rupture zones of the great Bihar, 1934, and Kangra, 1905, earthquakes has not experienced a great earthquake for at least 200 years, and perhaps for as long as 750 years. The observed rate of occurrence of earthquakes is evidently too low to accommodate lndo/Tibetanslip which must therefore be accommodated by creep or occasional great earthquakes. Creep processes do not appear to be sufficiently fast, at least in central Nepal, where levelling data in the last two decades, and GPS data in the past 3 years, have been interpreted to account for at most 7 mm/year, or 30% of the inferred ≈20 mm/yr convergence signal. The measurement of 19th century geodetic networks in northern India, which have hitherto been neglected, potentially provides an estimate the rate of accumulation of elastic strain in W. Nepal. In view of the possibly disastrous consequences to the many tens of millions inhabitants of northern India and Nepal who would be affected by a great earthquake, an intense effort to explore further the historic record and the geographic limits of historic and future rupture is desirable.

Within the Muon Ionization Cooling Experiment (MICE), the MICE Analysis User Software (MAUS) framework performs both online analysis of live data and detailed offline data analysis, simulation, and accelerator design. MAUS consists of four key components: inputters to handle input of live, archived or simulated data; transforms to analyse data; mergers to summarise transformed data in the form of histograms and tables; and outtputters to save this summarised data as images or tabular data. MAUS supports parallel data transformation in a map-reduce-inspired approach, however, the requirements of online reconstruction precluded adoption of a traditional map-reduce solution. A document-oriented database is used to cache transformed data, prior to merging, to support concurrent merging and visualisation of data. In MAUS, both offline and online analysis are implemented and executed in the same way, thereby removing the need for MICE to maintain and use two sets of analysis software, a common requirement elsewhere in experimental particle physics.

Shipboard magnetic investigation showed two zones of weak natural remanent magnetization (NRM): 675-925 and 1080-1243 meters below sea floor. Within these two sections, NRM intensity decreases by one to two orders of magnitude. Additional magnetic measurements onshore have shown similar fluctuations for NRM and saturation magnetization (/s). Js becomes almost zero in the low-NRM intensity zones, indicating a small magnetic content. The variation of relative magnetic grain sizes have been examined by the ratio of ARM/K0 (anhysteretic remanent magnetization to low magnetic field susceptibility) and by partial ARM (pARM) measurements. Both results indicate difference in magnetic grain sizes between the high- and low-intensity zones. For these Site 808 sediments, we have not found any correlation between magnetic intensity variation and sediment units. In addition, the calcite content varies only by a factor of 1.5 at the most, rather than 1 to 2 orders of magnitude, and therefore calcite dilution can not account for the low intensities. Because the changes in sediment sources and compositions can not explain these unusual magnetic phenomena, we suggest that the low-intensity zones may be inteΦreted in terms of deep-seated diagenetic alteration. Our study points out that (1) it may be difficult to establish a magnetostratigraphy for deep sediments due to extremely low NRM intensity, and (2) sudden decreases in NRM intensity may not result from an unusually low paleomagnetic field intensity.

Integrated sequence analysis of seismic and well data of the Givetian to Tournaisian sedimentary succession on the outer margin of the Lennard Shelf and adjacent Fitzroy Trough has recognized 18 third-order stratigraphic sequences in a major transgressive-regressive facies cycle. A Givetian phase of crustal extension initiated the transgressive-regressive cycle. The cycle terminated in the Tournaisian, following a phase of slow thermal subsidence. The transgressive half-cycle comprises at least four third-order sequences; an initial Frasnian-Givetian sequence followed by three backstepping Frasnian sequences. The regressive half-cycle comprises 14 basinward-advancing third-order sequences. A period of tectonic uplift and erosion immediately prior to the Frasnian-Famennian boundary resulted in a major basinward shift in coastal onlap in the initial stages of the regressive half-cycle. Systems tracts and facies are partitioned according to their position on the transgressive-regressive cycle; in the transgressive half-cycle, lowstand deposits are subdued and transgressive and highstand deposits accentuated. In the regressive half-cycle, lowstand deposits are accentuated and provide a foundation for the overlying transgressive and highstand deposits. The extent of basinward highstand progradation was limited by the break point of their underlying lowstand deposits. Sequence and systems tract geometries, their stacking patterns, and component facies define two distinct styles of sedimentation: (1) a Givetian to early Famennian, reef-rimmed platform complex; and (2) a late Famennian to Tournaisian mixed carbonate and siliciclastic ramp complex. The reef complex demonstrates marked reciprocal sedimentation. During lowstands, terrigenous sediments by-passed the exposed platform to be deposited in End_Page 157------------------------ the basin as basin floor fans, slope fans, and prograding complexes. During transgressions and highstands, carbonate sediments were deposited on the platform, allodapic carbonate particles were shed into proximal marginal-slope settings, and clastics were trapped on the inner platform. Lowstand carbonate production occurred locally in areas starved of terrigenous clastic influx. The recognition of relative sea-level cycles in these strata has led to a subsurface model of reef development, which provides new insights into the third-order cyclicity within the larger Pillara and Nullara cycles recognized from previous outcrop studies. The outcrop model of backstepping and advancing reef complexes emphasizes transgressive and highstand depositional systems, and fails to recognize phases o lowstand deposition.

As part an environmental assessment for the application of in situ leaching in an underground mine, the U.S. Bureau of Mines conducted a seismic crosshole tomographic investigation at the Colorado School of Mines experimental mine near Idaho Springs, CO. Seismic tomography was used to detect fractured regions as part of an investigation aimed at providing information that will help mining companies control solution during stope leaching. Whole waveform data provided both direct P-wave and S-wave traveltimes for input to the Bureau’s curved ray tomography program MIGRATOM, based on Huygens’ principle of wavefront propagation. The heterogeneous velocity distribution observed is attributed to the presence of both natural and blast induced fractures. The effectiveness of the tomographic method was corroborated by noting that low velocity zones occurred where water was lost in boreholes. The pre- and post-blast P-wave tomograms showed similar velocity distributions. This similarity in velocity tomograms suggests that the blast energy was contained resulting in minimal extension of existing fractures. Where changes in velocity were observed, they correlated to either natural fractures or blast induced damage. Tomograms also were produced showing the variation in dynamic elastic properties, including Poisson’s ratio, Young’s, shear, and bulk moduli. Such dynamic elastic properties assist in solving engineering problems associated with deformation, stability and blast design.