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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.
11

Tidal Cycle Effects on the Occurrence of the Florida Manatee (Trichechus manatus latirostris) at the Port Everglades Power Plant

Rappucci, Gina 19 October 2009 (has links)
The seasonal distribution of the Florida manatee (Trichechus manatus latirostris) is influenced predominantly by feeding locations in the summer and proximity to warm-water refuges during colder months. Due to their limited ability to tolerate cold water, when water temperatures drop below 20°C manatees congregate around natural and artificial warm-water refuges, such as warm-water springs or power plant outfalls. Distribution may further be influenced by the tidal cycle through its impact on manatee movement and foraging. Although the importance of tide on manatee distribution and habitat selection has been acknowledged, it has yet to be studied quantitatively in respect to the manatee population in southeast Florida. The purpose of this study was to examine the effect of the tidal cycle on manatee occurrence at the Florida Power & Light (FPL) Port Everglades Power Plant. Walking surveys were conducted in Port Everglades during manatee season, November 15 – March 31, between 2004 and 2008. During the surveys, the number of manatees in four established locations was noted and the animals categorized based on size as either calf, juvenile, or adult. Water temperature data were also collected at four permanent sample locations. Because many surveys yielded zero manatees observed, data were analyzed using the zero-inflated negative binomial model. Although the manatees at the Port Everglades Power Plant must forage away from the warm-water refuge, my findings show no correlation between tidal state and total manatee occurrence at the FPL Port Everglades Power Plant. The results do, however, suggest that the probability of observing a cow/calf pair is greater during high tide when compared to low and mid-tides (P < 0.05). Total manatee occurrence and the presence of cow/calf pairs were both significantly correlated with water temperature (P < 0.05).
12

The Effects of an Extended Power Plant Shutdown on the Florida Manatee (Trichechus manatus latirostris) in Port Everglades, Florida

Grissett, Christopher 01 November 2014 (has links)
Florida manatees (Trichechus manatus latirostris) seek out warmer waters during winter months when ambient water temperatures drop below 20 degrees Celsius. Over time, manatees have discovered artificial warm water sites from power plant discharges in addition to natural sites such as springs and passive thermal refugia (PTRs). The Florida Power and Light (FPL) Port Everglades power plant in Broward County is one such artificial warm water refuge used by manatees. This plant was shutdown on July 16, 2013, and is expected to remain off line for at least three years during demolition and construction of a new facility. The purpose of this study was to determine changes in habitat usage and other responses to the disruption of a warm water refugia (the closure of a power plant) on Florida manatees within the greater Port Everglades region. From November 15, 2013 to March 31, 2014, manatees were counted at the site via shore line and aerial surveys. Environmental data were collected to determine variables correlated to manatee presence and absense. Two manatees were radio-tagged using remote sensing devices in an effort to identify alternative warm water refugia and feeding areas. Data were collected from state and local organizations and photo-identified manatees were used to analyze for trends in cold stress syndrome (CSS) lesions and watercraft scarring. Results confirmed that manatee presence was positively correlated with heater outlet temperature. Differences did not exist between the results of survey methods between the FPL Port Everglades (PE) and Fort Lauderdale (FL) power plant sites, however, differrences in the aerial survey counts showed an increased presence at the FL site during the colder month of January 2014. Data from tagging identified one manatee that preferred the FL site while another preferred PE, presumably due to more convenient access to feeding grounds in Biscayne Bay. Data from mortality events indicated a low number of CSS and watercraft deaths in Broward County as compared to other parts of the state of Florida. Further monitoring of the study area for the remainder of the shutdown period is recommended, as are improvements in survey design, expansion to include additional environmental data from FL, continued mortality statistic analysis and locating possible PTRs.
13

Seasonal Aggregations of the Florida Manatee (Trichechus manatus latirostris) in the Port Everglades and Intracoastal Regions of Fort Lauderdale, Florida.

Goldman, Jaime M. 01 December 2010 (has links)
The Florida manatee (Trichechus manatus latirostris), a subspecies of the West Indian manatee, is one of the most endangered marine mammals in United States waters. The Florida manatee is the only manatee that ranges into subtropical and temperate regions. During the winter months manatees adopt a “refuging strategy” where they aggregate at warm-water sources immediately following decreases in the ambient water temperature to below 20° C (68° F) in order to avoid cold stress syndrome (CSS). During the winter manatees aggregate in warm water refuges, including natural warm water springs and the effluent discharges of power plants. The purpose of this study was to determine the number of manatees that aggregate and utilize the waters of the Florida Power and Light (FPL) Plant in Port Everglades (PPE), Florida, its effluent canal, and the surrounding Intracoastal Waterway during the winter months. This study documents the importance of Port Everglades as a wintering refuge for the Florida manatee. This study analyzed the inverse relationship between the number of manatees present at a warm water effluent and water temperature. In this study data were collected over five manatee winter seasons (between 15 November and 31 March) from 1999-2004, from both boat-based and land-based surveys monitoring the presence of manatees in the effluent canal from the FPL electricity generating facility in Port Everglades, FL and the Intracoastal Waterway. Findings indicated that there was an inverse relationship between the number of manatees present and water temperature, where more manatees were present in cooler months, and fewer in warmer months. This study also analyzed the parameters of Catch per Unit Effort (CPUE) as well as heating degree-days and their effect on and relationship to the number of manatees present. The higher the heating degree-days number, the more severe, or cold, winter this indicates. The year with the highest heating degree-days, 24.98, was the 2002-2003 season, which was also the season with the highest number of manatees observed, 393, and the highest CPUE, 10.62 manatees/day.
14

L'effet des enrochements sur l'utilisation de l'espace par les communautés de poissons dans les Basses-Terres du Saint-Laurent

Asselin, Joanie 01 1900 (has links)
No description available.
15

Provozní účinnosti zdrojů tepla / Performance of heat

Kocandová, Karolína January 2018 (has links)
The topic of the diploma thesis is the operational efficiency of heat sources . The thesis is divided into three parts. In the first part a theoretical solution of the heat sources efficiency can be found. In the second part there is a calculation solution of the project. The project solves the heating of a football stadium. Two variants of the heating source and warm water preparation are suggested and the variants are consequently compared and evaluated. The last part is experimental - the topic of the experiment is the efficiency of heat sources.
16

Kotelny na biomasu / Biomass boiler room

Egerle, Dušan January 2013 (has links)
The aim of this project is heating and warm water preparation for apartment block in Choceň (Pardubice region). Apartment block has three aboveground heated floors and one underground unheated floor. The heat source is gasifying firewood boiler or pellet boiler which is at the same time used for water heating but only in the winter time. The other parts of the year the solar collectors are installed and used for water heating. The heat source is located in detached room with its own access, in boiler room.
17

Účinnost rozvodů tepla / The efficiency of heat distribution

Vích, Pavel January 2015 (has links)
This diploma thesis focuses on the analysis of heat loss of heating distribution in the industrial area. The aim of this labor is to determine heat loss heat distribution kept in non manholed canal and evaluate economic return to build a local source of heat for the office building. For this building is in two variants resolve the reconstruction of the existing heating system. For the first variant is designed the local gas condensing boiler and for second variant existing central heat source. The experimental part of this labor compares the measured and calculated values of boundary conditions of hot-water pipes kept in non manholed canal.
18

Teplovzdušný vytápěcí a větrací systém pro nízkoenergetický rodinný dům / Warm-air heating and ventilating system for low-energy family house

Musil, Zdeněk January 2012 (has links)
The diploma thesis deals with warm-air heating and ventilation system of energyefficient family house. The part of thesis is theoretical introduction to low-energy and passive houses, ventilation and heating. The proposal itself is based on the applicable standards and includes all progressive steps, including the calculation of the thermal performance and sizing individual parts of the system. The drawing project documentation is listed in appendixes.
19

Diatoms from the late Holocene of the western Chukchi Sea, Arctic Ocean: environmental signals and palaeoceanography / Diatoméer från sen holocen i västra Tjukjerhavet, Arktiska oceanen: miljösignaler och paleoceanografi

Browaldh, Erik January 2022 (has links)
The sediment Core SWERUS-L2-2-PC1 (2PC) retrieved from the Chukchi Sea, Arctic Ocean sits in an oceanographically dynamic location at the Arctic-Pacific Ocean gateway. The 8.3 m-long core was retrieved in Herald Canyon at the marginal ice zone at 57 m depth. Core 2PC is well-positioned to record variability in inflow of Bering Sea Water (BSW) and Pacific Water (PW) in Herald Canyon. With the 2PC high sedimentation rate (200 cm/kyr), two independent age models (radiocarbon and palaeomagnetism) based on tephra age markers, and a richness in well-preserved siliceous sediment, validate 2PC as an outstanding sequence for applying diatom assemblage analysis as a proxy for ocean-climate change back to 4250 years BP, including the past few hundred years where global warming and sea ice decline is recorded by instrumental records. These characteristics make Core-2PC a useful record for investigating the role of PW on sea ice variability in the Chukchi Sea, both in the past and predicting the future. To investigate the impact of PW on ocean and sea ice conditions in the Chukchi Sea, diatom assemblage analysis was performed on 49 samples through the Late Holocene. The over-arching goal was to test the hypothesis, suggested by existing research on 2PC using benthic foraminifera Mg/Ca palaeothermometry, that the strength of PW inflow into the Chukchi Sea via Herald Canyon has varied on a time scales of ~500-1000 years in the past 4000 years. PW is slightly warmer than resident Arctic surface waters and is known to be an important control on Arctic sea-ice. The diatom assemblage approach assumes that there are recognizable differences between end-member diatom assemblages that are characteristic of PW versus Arctic Ocean type environments associated with extensive sea-ice conditions. The mapping of species in the Herald Canyon was used to test the idea of variability of sea-ice extent and the role of the Pacific Ocean forcings into the western Chukchi Sea. The results reveal diverse diatom assemblages throughout the past 4000 years in Herald Canyon, showing this core to be very useful for diatom palaeoclimate reconstructions. A total of 126 species with abundance &gt;1% are recognized. Several generalist species typically dominate assemblages especially Chaetoceros, ice-algae, marine-neritic and near ice or cold-water planktic centric diatoms. Distinct changes in stratigraphy are illustrated by changes in identified diatom assemblage zones. The 2PC diatom assemblages were contrasted with records from Chukchi-, Laptev-, East Siberian- and Bering Sea and North Pacific Ocean. At 2PC, sympagic (sea-ice related), planktic and neritic species abundance varies on time scales of ~500-1000 years. Importantly, there is a clear similarity between the timing of diatom assemblage changes and the 2PC benthic foraminifera Mg/Ca bottom water temperature (BWT) reconstruction. In particular, abundance changes in the warm water species Thalassionema nitzschioides, Shionodiscus oestrupii and Thalassionema simonsenii, tychoplanktic Paralia sulcata, Ice algae- and sympagic assemblages and cold-water indicators correspond best to BWT fluctuations shown by the Mg/Ca reconstruction. These oscillations are suggestive of changes in warmer PW inflow. Other aspects of the diatom data appear to correlate with colder and warmer climate events and suggest that changes in PW inflow amplified the effects of these events in the Chukchi Sea region through the Late Holocene in the Northern Hemisphere. It can thus, be concluded that diatoms from 2PC, support the palaeoceanographic reconstruction suggested by the benthic foraminifera Mg/Ca palaeothermometry and that variations in PW inflow through Herald Canyon is an important driver of sea ice variability on thousand-year time scales.

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