Monitoring the condition of our nation's ecological resources.

Mode of access: Internet.

GE core engine noise investigation - low emission engines /

Mode of access: Internet.

Potential relaxation of Illinois sulfur dioxide regulations and source-specific emission limits and their effect on the use of Illinois coal /

"October, 1983."

Source monitoring and evaluation of sediment inputs for Peoria Lake /

"ILENR/RE-WR-93/01."

Organizational maintenance repair parts and special tools lists : crane, wheel mounted, 20 ton at 10 foot radius, 2 engines, diesel engine driven, 4x4 air transportable, phase III, w/blade, bulldozer, earth moving, w/block,tackle, 20 ton, w/boom, crane, 30 foot, Army model M2380, NSN 3810-00-763-7728, American Hoist and Derrick model 2380 and Army model M2385 ...

Includes index.

Direct support and general support maintenance repair parts and special tools lists (including depot maintenance repair parts and special tools lists) : crane, wheel mounted, 20 ton at 10 foot radius, 2 engines, diesel engine driven, 4x4 air transportable, phase III; ...

Includes index.

Direct support and general support repair parts and special tools list (including depot maintenance repair parts and special tools list) for crane, wheel mounted, 20 ton at 10 foot radius, 2 engines, diesel engine driven, 4 x 4 air transportable, Harnischfeger Corp. model M320RT, (NSN 3810-00-275-1167).

Includes index.

Direct support and general support maintenance manual for crane, wheel mounted, 20-ton at 10-foot radius, 2 engines, diesel engine driven, 4x4 air transportable, Harnischfeger Corp. model M320RT (NSN 3810-00-275-1167).

"September 1977."

Operator's and organizational maintenance manual : crane, wheel mounted, 20-ton at 10-foot radius, 2 engines, diesel engine driven, 4 x 4 air transportable, Harnischfeger Corp. model M320RT (NSN 3810-00-275-1167).

Includes indexes.

Organizational maintenance repair parts and special tools lists : crane, wheel mounted, 20-ton at 10-foot radius, 2 engines, diesel engine driven, 4 x 4 air transportable for Harnischfeger Corp. model M320RT (NSN 3810-00-275-1167).

Includes index.

Intermediate direct support and intermediate general support maintenance repair parts and special tools lists ... : crane, wheel mounted, 20 ton at 10 foot radius, 2 engines, diesel engine driven, 4x4, air transportable, phase III; w/blade, bulldozer, earth moving; w/block, tackle, 20 ton; w/boom, crane 30 foot, Army model M2380 ....

"November, 1988."

Entanglement induced by spontaneous emission in spatially extended two-atom systems

The role of the collective antisymmetric state in entanglement creation by spontaneous emission in a system of two non-overlapping two-level atoms has been investigated. Populations of the collective atomic states and the Wootters entanglement measure (concurrence) for two sets of initial atomic conditions are calculated and illustrated graphically. Calculations include the dipole-dipole interaction and a spatial separation between the atoms that the antisymmetric state of the system is included throughout even for small interatomic separations. It is shown that spontaneous emission can lead to a transient entanglement between the atoms even if the atoms were prepared initially in an unentangled state. It is found that the ability of spontaneous emission to create transient entanglement relies on the absence of population in the collective symmetric state of the system. For the initial state of only one atom excited, entanglement builds up rapidly in time and reaches a maximum for parameter values corresponding roughly to zero population in the symmetric state. On the other hand, for the initial condition of both atoms excited, the atoms remain unentangled until the symmetric state is depopulated. A simple physical interpretation of these results is given in terms of the diagonal states of the density matrix of the system. We also study entanglement creation in a system of two non-identical atoms of different transition frequencies. It is found that the entanglement between the atoms can be enhanced compared to that for identical atoms, and can decay with two different time scales resulting from the coherent transfer of the population from the symmetric to the antisymmetric state. In addition, it was found that a decaying initial entanglement between the atoms can display a revival behaviour.

Entangled two-photon source using biexciton emission of an asymmetric quantum dot in a cavity

A semiconductor based scheme has been proposed for generating entangled photon pairs from the radiative decay of an electrically pumped biexciton in a quantum dot. Symmetric dots produce polarization entanglement, but experimentally realized asymmetric dots produce photons entangled in both polarization and frequency. In this work, we investigate the possibility of erasing the “which-path” information contained in the frequencies of the photons produced by asymmetric quantum dots to recover polarization-entangled photons. We consider a biexciton with nondegenerate intermediate excitonic states in a leaky optical cavity with pairs of degenerate cavity modes close to the nondegenerate exciton transition frequencies. An open quantum system approach is used to compute the polarization entanglement of the two-photon state after it escapes from the cavity, measured by the visibility of two-photon interference fringes. We explicitly relate the two-photon visibility to the degree of the Bell-inequality violation, deriving a threshold at which Bell-inequality violations will be observed. Our results show that an ideal cavity will produce maximally polarization-entangled photon pairs, and even a nonideal cavity will produce partially entangled photon pairs capable of violating a Bell-inequality.

Water quality condition and trend in North Queensland waterways

The Queensland Environmental Protection Agency monitored water quality at 133 sites in North Queensland waterways between Cooktown and Bundaburg from 1992 to 2001. Condition of the waterways was rated by comparing recent data with the Queensland Water Quality Guidelines. Long-term trends were analysed using a censored regression technique that incorporates the effects of flow, temperature, seasonality and allows for long-term non-linear trends. Many sites were in good condition; those in poor condition were usually impacted by point source discharges; those in moderate condition were usually impacted by agricultural land use. There were no consistent long-term trends across the whole region. Recommendations for future programs include incorporating pressure indicators, ensuring high standards of quality assurance, including covariates such as rainfall in trend assessment and continuing programs over more than 10 years to allow detection of trends due to changes in land-use. (c) 2004 Elsevier Ltd. All rights reserved.

Monitoring the condition of savanna riparian zones in Northern Australia using high spatial resolution imagery and a field based rapid assessment method

Government agencies responsible for riparian environments are assessing the combined utility of field survey and remote sensing for mapping and monitoring indicators of riparian zone condition. The objective of this work was to compare the Tropical Rapid Appraisal of Riparian Condition (TRARC) method to a satellite image based approach. TRARC was developed for rapid assessment of the environmental condition of savanna riparian zones. The comparison assessed mapping accuracy, representativeness of TRARC assessment, cost-effectiveness, and suitability for multi-temporal analysis. Two multi-spectral QuickBird images captured in 2004 and 2005 and coincident field data covering sections of the Daly River in the Northern Territory, Australia were used in this work. Both field and image data were processed to map riparian health indicators (RHIs) including percentage canopy cover, organic litter, canopy continuity, stream bank stability, and extent of tree clearing. Spectral vegetation indices, image segmentation and supervised classification were used to produce RHI maps. QuickBird image data were used to examine if the spatial distribution of TRARC transects provided a representative sample of ground based RHI measurements. Results showed that TRARC transects were required to cover at least 3% of the study area to obtain a representative sample. The mapping accuracy and costs of the image based approach were compared to those of the ground based TRARC approach. Results proved that TRARC was more cost-effective at smaller scales (1-100km), while image based assessment becomes more feasible at regional scales (100-1000km). Finally, the ability to use both the image and field based approaches for multi-temporal analysis of RHIs was assessed. Change detection analysis demonstrated that image data can provide detailed information on gradual change, while the TRARC method was only able to identify more gross scale changes. In conclusion, results from both methods were considered to complement each other if used at appropriate spatial scales.