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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
251

Anaerobic Co-digestion of Sewage sludge, Algae and Coffee Ground

Flisberg, Kristina January 2016 (has links)
Energy shortfall and air pollution are some of the challenges the human kind is facing today. Fossil fuel is still the most widely used fuel, which is a non-renewable resource, increasing excess carbon dioxide into the air. To overcome these issues, and reduce the carbon footprint, a greater development of renewable energy from green and natural resources is required. Compared to fossil energy, renewable energy has the benefit to reduce greenhouse gas emissions. There are different solutions available for green and renewable energy. Biomass is all biologically produced matter. Through the biological breakdown of biomass, biogas can be produced through the process called anaerobic digestion. This work was focused on the production of biogas, using algal biomass, sewage sludge and coffee grounds in an anaerobic co-digestion system. The main goal of this study was to investigate the feasibility of combining these three substrates. Two different types of algae were employed; Chlorella vulgaris and Scenedesmus sp. and the investigations included even the cultivation and harvesting of algal biomass. The production of biogas was examined under anaerobic conditions using 5 batch reactors in duplicate under constant temperature of 37 °C in 30 days. The result showed that co-digestion of algal biomass with sewage sludge led to an enhanced biogas production by 75 % compared to that of just sewage sludge. This indicates the synergistic effects of co-digestion. However, the addition of coffee ground to the mixture lowered the biogas production. All mixtures except the two with coffee grounds were in neutral pH. Methanogens, involved in the last step in biogas production are very sensitive to pH, and pH around 7 is the optimal for their activity. Furthermore, the presence of caffeine in the coffee ground could also inhibit the biogas production.
252

The ecology of small predatory beetles, with special reference to their competitive relations

Davies, Michael January 1955 (has links)
No description available.
253

IMACCS: A Progress Report on NASA/GSFC's COTS-Based Ground Data Systems, and Their Extension into New Domains

Scheidker, E. J., Pendley, R. D., Rashkin, R. M., Weking, R. D., Cruse, B. G., Bracken, M. A. 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / The Integrated Monitoring, Analysis, and Control COTS System (IMACCS), a system providing real time satellite command and telemetry support, orbit and attitude determination, events prediction, and data trending, was implemented in 90 days at NASA Goddard Space Flight Center (GSFC) in 1995. This paper describes upgrades made to the original commercial, off-the-shelf (COTS)-based prototype. These upgrades include automation capability and spacecraft Integration and Testing (I&T) capability. A further extension to the prototype is the establishment of a direct RF interface to a spacecraft. As with the original prototype, all of these enhancements required lower staffing levels and reduced schedules compared to custom system development approaches. The team's approach to system development, including taking advantage of COTS and legacy software, is also described.
254

800 Mbps TELEMETRY PROCESSING SYSTEM

Bishop, Jim, Welch, John 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / Satellites are becoming more capable and complex, as such their downlink requirements are increasing. In addition, future satellite systems will be operating at Ka-band that provides ample bandwidth to support the increase in downlink rates up to 800 Mbps. This paper describes a new generation commercial solution that can support 800 Mbps telemetry processing for data reception, frame synchronization, time tagging, Reed-Solomon forward error correction, data routing, data storage, data playback for testing, networking, and Bit Error Rate (BER) Testing.
255

TELEMETRY SYSTEMS DESIGN TO SUPPORT THE AUSTRALIAN DEFENSE FORCE AT THE EAST AUSTRALIA (JERVIS BAY RANGE) AND OTHER LAND OR OPEN OCEAN EXERCISE LOCATIONS

Bennett, Wayne, Peterson, Dwight M. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / The Royal Australian Navy (RAN) Sonar and Ranges Group (S&RG) office has a requirement to provide a dual weapon capable Mobile Missile Telemetry Range (MMTR) and data analysis system to upgrade their Jervis Bay Range telemetry ground station for supporting at-sea testing of air and surface launched guided weapon, decoy, and target systems. This paper describes the design and development of the MMTR and data analysis system used to support the Jervis Bay Range and the acquisition strategy used to procure the system. Unique design features of the MMTR system include a dual use packaging scheme which permits the system to be transported to any suitable land based location or deployed as two independent shipboard telemetry receiving systems. In addition, the paper describes antenna, receiver, recording, matrix switching, processing, display, and communication subsystem components used within the MMTR system.
256

THE PHILLIPS LABORATORY’S MOBILE GROUND TRACKING STATION (MGTS)

Stone, Christopher E., Flint, Keith D., Mathis, Gregory P. 11 1900 (has links)
International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / Phillips Laboratory's Space Experiments Directorate (PL/SX) is operating and upgrading the laboratory's premier transportable satellite tracking station, the Mobile Ground Tracking Station (MGTS) program. MGTS supports orbital, suborbital, and aircraft missions as a range system capable of processing and recording multiple data streams. MGTS receives, processes, displays, and records satellite state-of-health data, infrared images in a variety of wavelengths, video data, and state vector solutions based on IR returns from the Miniature Sensor Technology Integration (MSTI) satellite program. The program has began in 1990 under BMDO sponsorship, with the intent to supplement existing test ranges with more flexibility in range operations. Wyle Laboratories and Systems Engineering and Management Company (SEMCO) provided the technical expertise necessary to create the first MGTS system. Autonomy and off-road capability were critical design factors, since some of the operations envisioned require deployment to remote or hostile field locations. Since inception, MGTS has supported the Lightweight Exo-Atmospheric Projectile (LEAP) sub-orbital missions, the MSTI satellite program, and Air Force wargame demonstrations. In pursuit of these missions, MGTS has deployed to White Sands Missile Range (WSMR), NM; Air Force Flight Test Center (AFFTC), Edwards AFB, CA; Vandenberg AFB, CA; Falcon AFB, CO; and NASA's Wallops Island Flight Facility, VA, to receive critical mission telemetry data conforming to both IRIG and SGLS standards. This paper will describe the evolution of the MGTS program, current hardware configurations and past and future mission scenarios for the MGTS team.
257

Age-related deficits in inhibition in figure-ground assignment

Anderson, John A. E., Healey, M. Karl, Hasher, Lynn, Peterson, Mary A. 06 May 2016 (has links)
We assessed age differences in the ability to resolve competition for figural status in stationary displays using small, enclosed, symmetrical silhouettes that participants classified as depicting "novel'' or "familiar'' shapes. The silhouettes were biased such that the inside was perceived as the shaped figure, and the outside was perceived as a shapeless ground. The critical manipulation was whether a portion of a meaningful object was suggested on the outside of the border of some of the novel silhouettes but not others M(+)Ground and M-Ground novel silhouettes, respectively). This manipulation was intended to induce greater inhibitory competition for figural status from the groundside in M(+)Ground silhouettes than M(-)Ground silhouettes. In previous studies, young adults classified M(+)Ground silhouettes as "novel'' faster than M(-)Ground silhouettes (Trujillo, Allen, Schnyer, & Peterson, 2010), suggesting that young adults may recruit more inhibition to resolve figure-ground when there is more competition. We replicated this effect with young adults in the present study, but older adults showed the opposite pattern and were less accurate in classifying M(+)Ground than M(-)Ground silhouettes. These results extend the evidence for inhibitory deficits in older adults to figure assignment in stationary displays. The (M(+)Ground - M(-)Ground) RT differences were evident in observers' longest responses, consistent with the hypothesis that inhibitory deficits are evident when the need for inhibition is substantial.
258

The stability of development tunnels sited adjacent to previous excavations

Sharpe, Leigh January 1999 (has links)
No description available.
259

Carabid ecology in organic and conventional farming systems : population density, diversity and high resolution spatial dynamics

Brown, Nicola Jane January 2000 (has links)
No description available.
260

Ground Covers for Northern Arizona above 6000 Foot Elevations

DeGomez, Tom 08 1900 (has links)
6 pp. / Ground covers can be any low-growing, creeping, sprawling plant whose primary purpose is to cover the ground in managed landscapes. General planting instructions, their care, selection and cultural requirements used in ground cover and explained in this article in detail.

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