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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.
21

Numerical modeling of buried pipes with flowable fill as a backfill material

Mada, Hemachandar. January 2005 (has links)
Thesis (M.S.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains x, 157 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 128-132).
22

Creep in sands a study of time dependent deformation of reclamation sand fill under constant effective stress /

Ching, Peter. January 2001 (has links)
Thesis (M. Sc.)--University of Hong Kong, 2001. / Also available in print.
23

Impact of Inventory Control Reduction on Customer Satisfaction and Partial Fill Costs

Castaneda, Daniel, Lenzie, Kent January 2005 (has links)
Class of 2005 Abstract / Objectives: To determine the impact of tightly controlled inventory reduction on customer satisfaction and partial fill costs. Methods: The project was a cross-sectional study employing two survey instruments and a time in motion analysis to determine the number of “we-owes” filled by pharmacies due to inventory reduction, the costs that arise from such reductions, and the impact on customer satisfaction. The first survey instrument was sent to four pharmacies in the Fry’s Food and Drug chain. The survey assessed number of “we-owes” per pharmacy and reasons for having them. The second survey consisted of several statements concerning customer satisfaction. The participants were asked to rate their agreement with each statement using a response scale from 1 (strongly disagree) to 5 (strongly agree). A time-in-motion analysis was performed at two pharmacies averaging 350 prescriptions per day to record the amount of labor involved in filling “we-owes". Results: Medium to high volume Fry’s pharmacy fills an average of forty “we owes” each week. The average yearly costs for filling the “we owes” ranges from $171,579 to $568,796 per year depending on the job status of people filling the “we owes.” The main reason for these partially filled prescriptions was the minimum order point was incorrect accounted for 53.8% of the “we owes Almost half of customers owed medication felt it was not inconvenient them to pick the remainder of their prescription and that over half have had this happen more than once. Implications: The costs of tight inventory control need to be compared with the savings obtained from maintaining marginal inventories.
24

Use Of Vegetative Mulch As Daily And Intermediate Landfill Cover

Haddad, Assal Edwar 01 January 2011 (has links)
Management of yard waste is a significant challenge in the US, where in 2008 13.2% of the 250 million tons of municipal solid waste (MSW) was reported to be yard waste. This study describes research conducted in the laboratory and field to examine the application of vegetative mulch as daily and intermediate landfill cover. Mulch was found to exhibit stronger physical properties than soil, leading to a more stable landfill slope. Compaction of mulch was found to be significantly greater than soil, potentially resulting in airspace recovery. Degradation of mulch produced a soil-like material; degradation resulted in lower physical strength and hydraulic conductivity and higher bulk density when compared with fresh mulch. Mulch covers in the field permitted higher infiltration rates at high rain intensities than soil covers, and also generated less runoff due to greater porosity and hydraulic conductivity as compared to soil. Mulch covers appear to promote methane oxidation more than soil covers, although it should be noted that methane input to mulch covers was more than an order of magnitude greater than to soil plots. Life cycle assessment (LCA) showed that, considering carbon sequestration, use of green waste as landfill cover saves GHG emissions and is a better environmental management option compared to composting and use of green waste as biofuel.
25

Ecotoxicological Evaluation of Hollow Fill Drainages in Low Order Streams in the Appalachian Mountains of Virginia and West Virginia

Merricks, Timothy Chad 09 June 2003 (has links)
Hollow fills are composed of excess spoil and debris produced from surface coal mining that is not returned to the original mined site. Hollow fills are often constructed in the head of hollows nearby or adjacent to the mined land area, which may be the origins of headwater streams or drain into low order systems. Eleven hollow fills were utilized in evaluating the influence fill drainages had on low order streams in Virginia and West Virginia. The study was conducted in six watersheds including; Five Mile Creek in Mingo County, West Virginia, Trace Fork in Mingo County, West Virginia, Lavender Fork in Boone County, West Virginia, Middle Creek in Tazewell County, Virginia, South Fork of the Pound River in Wise County, Virginia, and Powell River in Wise County, Virginia. Bioassessment procedures used in the evaluation of hollow fill drainages included water/sediment chemistry, acute water column toxicity testing using <i>Ceriodaphnia dubia</i>, chronic sediment toxicity testing using <i>Daphnia magna</i>, benthic macroinvertebrate surveys, and <i>in situ</i> Asian clam (<i>Corbicula fluminea</i>) toxicity testing. Common significant differences in water quality between reference and fill influenced sites, among all watersheds, were elevated conductivity and water column metal concentrations, particularly aluminum and copper. Water column and sediment toxicity testing reported limited significant mortality or reproductive impairment associated with hollow fill drainages. The West Virginia watersheds used in the study consisted of headwater streams originating directly from the settling ponds, placed at the base of the hollow fills, receiving drainages from the fills. Benthic macroinvertebrate analysis reported no significant alteration in total taxa or EPT richness downstream of the ponds. Yet, collector filterer populations, including benthic macroinvertebrates and <i>in situ</i> Asian clams, were enhanced directly downstream of the ponds due to organic enrichment originating from the ponds. A decrease in collector filterer populations and lowered clam growth suggested the organic enrichment dissipated downstream from the ponds. Chlorophyll <i>a</i> analysis of the phytoplankton community was not significantly related to the enhance collector filterer populations in the streams, however the high concentrations in the settling ponds suggest abundant algal communities. The hollow fills evaluated in Virginia drained into receiving systems, whose headwater origins were not directly related to hollow fill drainages. Low taxa richness was associated with the hollow fill and settling pond drainages, however receiving system sites were minimally influenced. Yet, as reported in the West Virginia watersheds, the settling ponds input organic enrichment that enhanced collector filterer populations, including benthic macroinvertebrates and <i>in situ</i> test clams. An analysis of the hollow fills' age, or maturity, reported no significant difference between young and old fills. In general, a common feature of among the various aged fill drainages was elevated conductivity, compared to reference sites of the watersheds. / Master of Science
26

Tree planting on recently-restored landfills: a study of a native species.

January 2003 (has links)
Chong Chun-wing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 151-165). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.v / Table of Contents --- p.vii / List of Tables --- p.x / List of Figures --- p.xii / List of Plates --- p.xiii / List of Appendix --- p.xiv / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Waste management in Hong Kong --- p.1 / Chapter 1.2 --- Landfilling --- p.1 / Chapter 1.2.1 --- Definition --- p.1 / Chapter 1.2.2 --- Landfill design --- p.3 / Chapter 1.2.3 --- Waste degradation --- p.5 / Chapter 1.2.3.1 --- Landfill leachate --- p.5 / Chapter 1.2.3.2 --- Landfill gas --- p.6 / Chapter 1.2.3.3 --- Effective control of degraded by-products --- p.8 / Chapter 1.2.4 --- General practices after completion of landfills --- p.9 / Chapter 1.2.4.1 --- Final capping system --- p.9 / Chapter 1.2.4.2 --- Revegetation on final cover --- p.1 / Chapter 1.2.4.3 --- Post-closure management --- p.11 / Chapter 1.2.4.4 --- Afteruses --- p.12 / Chapter 1.3 --- Reclamation of closed landfills --- p.13 / Chapter 1.3.1 --- Selecting afteruse and setting ultimate ecological goal of a closed landfill --- p.14 / Chapter 1.3.1.1 --- Important considerations on landfill reclamation --- p.14 / Chapter 1.3.1.2 --- Land reclamation and ecosystem development --- p.14 / Chapter 1.3.1.3 --- Choice In Hong Kong --- p.16 / Chapter 1.3.2 --- Limitations to revegetation --- p.17 / Chapter 1.3.2.1 --- Physical problems --- p.17 / Chapter 1.3.2.2 --- Shallow soil --- p.18 / Chapter 1.3.2.3 --- Drought and waterlogging --- p.18 / Chapter 1.3.2.4 --- Nutrient deficiencies --- p.19 / Chapter 1.3.2.5 --- Landfill gas and leachate --- p.19 / Chapter 1.3.3 --- Selecting the suitable species --- p.20 / Chapter 1.4 --- Plantations and closed landfills --- p.22 / Chapter 1.4.1 --- The roles of plantations --- p.23 / Chapter 1.4.1.1 --- Enhancing soil development --- p.24 / Chapter 1.4.1.2 --- Modifying microclimate --- p.25 / Chapter 1.4.1.3 --- Facilitate natural invasion --- p.25 / Chapter 1.4.2 --- Exotics or natives? --- p.25 / Chapter 1.4.3 --- Knowledge learned from natural invasion --- p.27 / Chapter 1.4.4 --- Human management or aftercare --- p.28 / Chapter 1.5 --- Objectives of this research --- p.28 / Chapter 1.5.1 --- Knowledge gap --- p.28 / Chapter 1.5.2. --- Objectives --- p.29 / Chapter Chapter 2 --- Study Sites --- p.31 / Chapter 2.1 --- General descriptions --- p.31 / Chapter 2.2 --- Locations --- p.34 / Chapter 2.3 --- Climate --- p.36 / Chapter Chapter 3 --- Soil Status of Closed Landfills --- p.38 / Chapter 3.1 --- Introduction --- p.38 / Chapter 3.2 --- Materials and methods --- p.40 / Chapter 3.2.1 --- Landfill gas and soil moisture determination --- p.40 / Chapter 3.2.2 --- Soil sampling and analysis --- p.41 / Chapter 3.2.2.1 --- Soil sampling and preparation --- p.41 / Chapter 3.2.2.2 --- Soil texture and water retention --- p.41 / Chapter 3.2.2.3 --- Bulk density and total porosity --- p.41 / Chapter 3.2.2.4 --- Soil pH and electrical conductivity --- p.42 / Chapter 3.2.2.5 --- Organic carbon --- p.42 / Chapter 3.2.2.6 --- Nitrogen --- p.42 / Chapter 3.2.2.7 --- Phosphorus --- p.43 / Chapter 3.2.2.8 --- Cations --- p.43 / Chapter 3.2.3 --- Statistical analysis --- p.43 / Chapter 3.3 --- Results and discussion --- p.44 / Chapter 3.3.1 --- Landfill gas and soil moisture contents --- p.44 / Chapter 3.3.2 --- Soil physical properties --- p.45 / Chapter 3.3.2.1 --- Bulk density and porosity --- p.45 / Chapter 3.3.2.2 --- Texture --- p.47 / Chapter 3.3.3 --- Soil chemical properties --- p.47 / Chapter 3.3.3.1 --- pH and electrical conductivity --- p.47 / Chapter 3.3.3.2 --- Organic carbon and matter --- p.49 / Chapter 3.3.3.3 --- Nitrogen and C:N ratio --- p.50 / Chapter 3.3.3.4 --- Phosphorus --- p.51 / Chapter 3.3.3.5 --- Potassium --- p.52 / Chapter 3.3.3.6 --- Other major cations --- p.53 / Chapter 3.3.4 --- Comparison among sites --- p.53 / Chapter 3.3.5 --- Comparison with other degraded sites --- p.54 / Chapter 3.3.6 --- Implications --- p.55 / Chapter 3.4 --- Conclusion --- p.57 / Chapter Chapter 4 --- "Screening Native Species for Revegetating ""Recently Restored"" Landfills I: Drought Resistance Trial" --- p.58 / Chapter 4.1 --- Introduction --- p.58 / Chapter 4.2 --- Materials and methods --- p.60 / Chapter 4.2.1 --- Principles --- p.60 / Chapter 4.2.2 --- Species selection --- p.63 / Chapter 4.2.3 --- General experimental design --- p.65 / Chapter 4.2.4 --- Soil source and analysis --- p.68 / Chapter 4.2.5 --- Statistical analysis --- p.68 / Chapter 4.3 --- Results and discussion --- p.68 / Chapter 4.3.1 --- Soil used for filling the trial pots --- p.68 / Chapter 4.3.2 --- Chlorophyll fluorescence --- p.70 / Chapter 4.3.3 --- Standing leaf number --- p.72 / Chapter 4.3.4 --- Overall evaluation --- p.76 / Chapter 4.3.5 --- Features of the more drought resistant species --- p.78 / Chapter 4.3.6 --- Limitations for the study --- p.79 / Chapter 4.4 --- Conclusion --- p.79 / Chapter Chapter 5 --- "Screening Native Species for Revegetating ""Recently Restored"" Landfills II: Field Trial" --- p.81 / Chapter 5.1 --- Introduction --- p.81 / Chapter 5.2 --- Materials and methods --- p.82 / Chapter 5.2.1 --- Tree planting --- p.82 / Chapter 5.2.2 --- Site environmental factors --- p.83 / Chapter 5.2.3 --- Survival and growth responses --- p.85 / Chapter 5.2.4 --- Ecophysiological responses --- p.85 / Chapter 5.2.5 --- Statistical analysis --- p.85 / Chapter 5.3 --- Results and discussion --- p.86 / Chapter 5.3.1 --- Environmental factors of Plot TNP --- p.86 / Chapter 5.3.2 --- Survival rate --- p.88 / Chapter 5.3.3 --- General growth performance --- p.91 / Chapter 5.3.4 --- Seasonal growth performance --- p.95 / Chapter 5.3.5 --- Ecophysiological responses --- p.99 / Chapter 5.3.5.1 --- Fv/Fm --- p.99 / Chapter 5.3.5.2 --- Stomatal conductance --- p.100 / Chapter 5.3.5.3 --- Transpiration rate --- p.102 / Chapter 5.3.6 --- Species selection --- p.103 / Chapter 5.3.7 --- Limitations and further studies --- p.105 / Chapter 5.4 --- Conclusion --- p.106 / Chapter Chapter 6 --- "Screening Native Species for Revegetating ""Recently Restored´ح Landfills III: Different Management Practices" --- p.107 / Chapter 6.1 --- Introduction --- p.107 / Chapter 6.2 --- Materials and Methods --- p.108 / Chapter 6.2.1 --- General experimental design and seedling preparation --- p.108 / Chapter 6.2.2 --- "Survival, Growth and chlorophyll fluorescence responses" --- p.109 / Chapter 6.2.3 --- Soil source and analysis --- p.109 / Chapter 6.2.4 --- Statistical analysis --- p.110 / Chapter 6.3 --- Results and Discussion --- p.110 / Chapter 6.3.1 --- Soil physical and chemical properties --- p.110 / Chapter 6.3.2 --- Survival rate --- p.112 / Chapter 6.3.3 --- General growth peformance --- p.114 / Chapter 6.3.3.1 --- Height growth --- p.114 / Chapter 6.3.3.2 --- Basal diameter growth --- p.119 / Chapter 6.3.4 --- Chlorophyll fluorescence --- p.123 / Chapter 6.3.5 --- Implications --- p.124 / Chapter 6.4 --- Conclusion --- p.125 / Chapter Chapter 7 --- "Performance of Two Years Old Native Saplings Planted on A ""Recently Restored"" Landfill" --- p.126 / Chapter 7.1 --- Introduction --- p.126 / Chapter 7.2 --- Materials and methods --- p.127 / Chapter 7.2.1 --- "Study plots, species selection and tree sampling" --- p.127 / Chapter 7.2.2 --- Site environmental factors --- p.128 / Chapter 7.2.3 --- Survival and growth responses --- p.128 / Chapter 7.2.4 --- Ecophysiological responses --- p.128 / Chapter 7.2.5 --- Statistical analysis --- p.128 / Chapter 7.3 --- Results and discussion --- p.129 / Chapter 7.3.1 --- Environmental factors of trial plots TA & TB --- p.129 / Chapter 7.3.2 --- Survival rate --- p.131 / Chapter 7.3.3 --- General growth performance --- p.133 / Chapter 7.3.4 --- Seasonal growth performance --- p.137 / Chapter 7.3.5 --- Ecophysiological responses --- p.140 / Chapter 7.3.5.1 --- Fv/Fm --- p.140 / Chapter 7.3.5.2 --- Stomatal conductance --- p.141 / Chapter 7.3.5.3 --- Transpiration rate --- p.142 / Chapter 7.3.6 --- Evaluation of different species --- p.143 / Chapter 7.3.7 --- Effects of ages --- p.144 / Chapter 7.4 --- Conclusion --- p.145 / Chapter Chapter 8 --- General Conclusions --- p.146 / Chapter 8.1 --- Summary of findings --- p.146 / Chapter 8.2 --- Further studies --- p.148 / References --- p.151
27

The structural collapse of silt-sand fills after flooding

Pang, Kwok-kay, 彭國機 January 1979 (has links)
published_or_final_version / Civil Engineering / Master / Master of Philosophy
28

Creep in sands: a study of time dependent deformation of reclamation sand fill under constant effectivestress

Ching, Peter., 秦培德. January 2001 (has links)
published_or_final_version / Applied Geosciences / Master / Master of Science
29

Stable isotope tracers of landfill leachate impacts on aquatic systems

North, Jessica C., n/a January 2006 (has links)
The present study aimed to determine whether stable isotope techniques can be universally applied to detect landfill leachate contamination in aquatic systems. Results of analysis of ��C in dissolved inorganic carbon ([delta]��C-DIC), deuterium and �⁸O in water ([delta]D-H₂O and [delta]�⁸O-H₂O), and �⁵N of dissolved inorganic nitrogen components ([delta]�⁵N-NH₄⁺ and [delta]�⁵N-NO₃⁻) were presented for leachate, surface, and ground water samples collected from seven landfills located throughout New Zealand between 2003 and 2006. The unique conditions within a landfill lead to measurable fractionations in the isotopic ratios of the products of degradation. Results of isotope and ancillary parameter analyses enabled the discernment of different types of leachate, resulting from different microbial processes within the landfill environment. The isotopic characterisation of leachate enabled improved interpretation of geochemical data from potentially impacted surface and ground waters, and provides useful insight to landfill development for landfill operators. A general isotopic fingerprint delineated by [delta]��C-DIC and [delta]D-H₂O values showed leachate to be isotopically distinct from uncontaminated surface and ground water for samples analysed in the present study. However, not all water samples identified as leachate-impacted via site-specific assessments exhibited isotopic values that overlapped with the general leachate fingerprint. This highlights the need to investigate each site individually, within the context of a possibly global leachate isotope signature. Site-specific investigations revealed the effectiveness of applying [delta]�⁸O-H₂O and [delta]�⁵N-NH₄⁺ or [delta]�⁵N-NO₃⁻, in addition to [delta]��C-DIC and [delta]D-H₂O analyses, to the detection of leachate impact on aquatic systems. Furthermore, ancillary parameters such as alkalinity and ammonium concentration enabled the construction of simple isotope mixing models for an estimate of the quantity of leachate contribution. Results of isotopic investigations of stream biota suggested potential for the development of bio-indicators to monitor leachate influence on aquatic ecosystems in landfill-associated streams. The present study demonstrated the probative power of stable isotope techniques applied to investigations of leachate impact on landfill-associated aquatic systems.
30

The design and performance of a pressure chamber for testing soil nails in loose fill

Junaideen, Sainulabdeen Mohamed. January 2001 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 119-123).

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