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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.
1151

Stabatiškių aikštelės efektyvių sausinimo galimybių analizė / Investigation on the effective drainage possibilities of Stabatiškė site

Ulickas, Paulius 30 May 2012 (has links)
Tiriamojo darbo objektas: Stabatiškės aikštelė. Tiriamojo darbo tikslas: išanalizuoti esamą Stabatiškės aikštelės situaciją ir parinkti galimus sausinimo sistemos techninius sprendinius. Tiriamojo darbo uždaviniai: 1. Išanalizuoti kalvotų žemių sausinimo ypatumus ir drėgmės pertekliaus priežastis; 2. Išanalizuoti Stabatiškės aikštelės gamtines sąlygas, numatyti bei parinkti tinkamas sausinimo priemones; 3. Įvertinti Stabatiškės aikštelės topografines, geologines bei hidrogeologines sąlygas; 4. Parinkti galimas sausinimo schemas ir apibūdinti atskirus jų elementus. Tiriamojo darbo metodika: tyrimams panaudoti geologinių, hidrologinių ir hidrogeologinių tyrimų duomenys, jie apibendrinti, susisteminti ir išanalizuoti. Atsižvelgiant į ilgaamžiškumo faktorių, pasiūlyti sausinimo sistemos techniniai sprendiniai. Tiriamojo darbo rezultatai: • atlikus Stabatiškės aikštelės tyrimų analizę, buvo nustatytos pagrindinės priežastys, kodėl teritorijoje toks drėgmės perteklius; • pagal turimus duomenis parinkta optimaliausia sausinimo priemonių sistema; • nustatyta jog teritorija geografiniu, geologiniu ir geotechniniu požiūriu tinkama žemo aktyvumo radioaktyviųjų atliekų saugyklos statybai; • atviri melioraciniai grioviai bei daugiasluoksnis drenažas, tinkamiausias būdas kontroliuoti perteklinį vandenį Stabatiškės aikštelėje. Išvados: Pagrindinis veiksnys lemiantis parinktą sausinimo sistemos tipą yra teritorijos paskirtis. Žinant saugyklos eksploatavimo trukmę (300 metų), reikia... [toliau žr. visą tekstą] / The subject of the research work: Stabatiske site. The aim of the study: analyze current situation of the Stabatiske site and choose drainage potential technical solutions. The specific aims of this study: 1. Analise the hilly land drainage characteristics and causes of excess moisture; 2. Analise Stabatiske site natural conditions and provide adequate drainage measures; 3. Evaluate Stabatiske site topography, geological and hydro-geological conditions; 4. Select the possible drainage schemes, and describe their individual elements. The methodology of the study: for research was using geological, hydrological and hydro-geological data which was summarized, analyzed and structured. To take account of long-lived factor was offer drainage system technical solutions. Results: • Carried out Stabatiske site research and analysis was identified the main reasons why the territory is in the excess moisture; • According to available data was choose optimal drainage system; • Established the geographic, geological and geotechnical point of view appropriate low-level radioactive waste storage facility construction; • Open reclamation ditches and multi-drainage, is the best way to control excess water in Stabatiske site. Conclusions: The main factor determining the selected type of drainage system is designed area. Knowing the storage lifetime (300 years), need for know suitable drainage complex for that period. Knowing the local water regime and soil composition, the best option to... [to full text]
1152

Poilsio aikštelės Kelyje Ryga – Kaliningradas įrangos projektas / The project of equipment of the leisure groud on the highway Riga - Kaliningradas

Sukackaitė, Inga 17 August 2012 (has links)
Projekto meninė idėja – Kelmės rajono centras. Projekto tikslas: padidinti vietos funkcionalumą, sukuriant meninę kompoziciją, kuri taptų papildoma informacija, stiprinančia krašto identitetą. Perplanuojant aikštelę įrengiama poilsio vieta, tvarkomos prieigos prie vandens. Likusi teritorija paliekama automobilių parkavimui. Akcentuojant projekto idėją naudojama centrinė kompozicija. Atsižvelgiant į klimatą ir vartotojų grupę, naudojamos atsparios ir pigios medžiagos. Didelis dėmesys skiriamas technologijos tvirtumui ir saugumui. Taip pat, greitam įrangos surinkimui ir pasatymui. / The idea of a project is a center of Kelme district. The project aim is to improve the functionality of a place, creating an artistic composition which is an additional information, strengthening the capacity of the national identity. There was created a new leisure ground and managed access to water in the stop area. The rest place will remain on the parking problem. There was used a central composition. There was designed new original benches, lighting, shed and plants around the centre of the composition. There was used cheap ant proof materials, as a stone, metal and wood.
1153

Gruntinio vandens lygio dinamikos tarpdrenyje tyrimai ir modeliavimas / The research and modeling of ground water level dynamics between the laterals

Vaičiukynas, Vilimantas 18 December 2013 (has links)
Iškritus krituliams ant žemės paviršiaus, dalis jų susigeria į gruntą, o kita dalis nuolydžio kryptimi teka link žemiausių reljefo vietų. Susigėrimo intensyvumas priklauso nuo grunto laidumo. Sunkiuose gruntuose vandens susigeria ir patenka į gilesnius grunto sluoksnius gana sunkiai dėl mažo grunto laidumo. Intensyviausiai vanduo nuo žemės paviršiaus teka drenažo tranšėjomis ir šalia jų. Šios vandens tekėjimo sąlygos tranšėjose susidaro pakitus grunto struktūrai, jas užverčiant. Laikui bėgant, drenažo tranšėjoje atsiradę plyšiai užnešami smulkiomis grunto dalelėmis. Tai įtakoja grunto vandens laidumo savybių prastėjimą. Norint pagerinti vandens nutekėjimą iš viršutinio dirvožemio sluoksnio, padėtų natūralios gamtoje sutinkamos medžiagos, įterptos skersai virš vamzdinio drenažo. Drenažo tranšėjų užpylimui naudojant poringas medžiagas, dalis atitekėjusio vandens akumuliuotųsi naujai įrengtose skersinėse drenažo tranšėjose. Tokios technologijos taikymas leistų padidinti sausinimo efektyvumą nekeičiant jau paklotų drenažo vamzdžių. Modeliuojant skersinių drenažo tranšėjų tankio įtaką vandens lygiui tarpdrenyje, nustatyta, kad papildomas jų įrengimas turi įtakos gruntinio vandens lygiams tarpdrenyje tik esant atstumui iki 30 m. Esant didesniam atstumui, jų poveikis gruntinio vandens lygio nuslūgimui tampa nežymus, siekia vos 1-2%. Didžiausią įtaką gruntinio vandens slūgimui tarpdrenyje turėjo skersinės drenažo tranšėjos įrengiamos 20 m tarpais, kai drenažo tranšėjos užpildo... [toliau žr. visą tekstą] / After rainfall, part of it is absorbed by the ground whereas the rest part flows upon the direction of the inclination towards the lowest points on the relief. Intensity of absorption depends on conductivity of the ground. In the hard ground water is absorbed and enters the deeper layers of the ground with difficulty due to low conductivity of the ground. Water flows most intensely through drainage trenches and next to them. These conditions of water flow in trenches form when the ground structure alters and overloads them. The time passing by, cracks, having occurred in the drainage trench, are filled with small ground particles. It influences deterioration of ground water conductivity qualities. In order to improve water runoff from the upper soil layer, natural substances found in nature, if inserted across, above the drain, could help. Using porous substances in order to cover drainage trenches, part of the water would accumulate in newly equipped cross-section drain trenches. Applying such a technology would allow increasing the efficiency of drainage without changing the already laid drainage pipes. Modeling the influence of cross-section drainage trench density on ground water level between drains, it was determined that additional installation could affect ground water level between the cross-section drains trench, the distance being up to 30 meters. When the distance is larger, its impact on the ground water level recession becomes insignificant and reaches only 1-2%... [to full text]
1154

Gruntinio vandens lygio dinamikos tarpdrenyje tyrimai ir modeliavimas / The research and modeling of ground water level dynamics between the laterals

Vaičiukynas, Vilimantas 18 December 2013 (has links)
Iškritus krituliams ant žemės paviršiaus, dalis jų susigeria į gruntą, o kita dalis nuolydžio kryptimi teka link žemiausių reljefo vietų. Susigėrimo intensyvumas priklauso nuo grunto laidumo. Sunkiuose gruntuose vandens susigeria ir patenka į gilesnius grunto sluoksnius gana sunkiai dėl mažo grunto laidumo. Intensyviausiai vanduo nuo žemės paviršiaus teka drenažo tranšėjomis ir šalia jų. Šios vandens tekėjimo sąlygos tranšėjose susidaro pakitus grunto struktūrai, jas užverčiant. Laikui bėgant, drenažo tranšėjoje atsiradę plyšiai užnešami smulkiomis grunto dalelėmis. Tai įtakoja grunto vandens laidumo savybių prastėjimą. Norint pagerinti vandens nutekėjimą iš viršutinio dirvožemio sluoksnio, padėtų natūralios gamtoje sutinkamos medžiagos, įterptos skersai virš vamzdinio drenažo. Drenažo tranšėjų užpylimui naudojant poringas medžiagas, dalis atitekėjusio vandens akumuliuotųsi naujai įrengtose skersinėse drenažo tranšėjose. Tokios technologijos taikymas leistų padidinti sausinimo efektyvumą nekeičiant jau paklotų drenažo vamzdžių. Modeliuojant skersinių drenažo tranšėjų tankio įtaką vandens lygiui tarpdrenyje, nustatyta, kad papildomas jų įrengimas turi įtakos gruntinio vandens lygiams tarpdrenyje tik esant atstumui iki 30 m. Esant didesniam atstumui, jų poveikis gruntinio vandens lygio nuslūgimui tampa nežymus, siekia vos 1-2%. Didžiausią įtaką gruntinio vandens slūgimui tarpdrenyje turėjo skersinės drenažo tranšėjos įrengiamos 20 m tarpais, kai drenažo tranšėjos užpildo... [toliau žr. visą tekstą] / After rainfall, part of it is absorbed by the ground whereas the rest part flows upon the direction of the inclination towards the lowest points on the relief. Intensity of absorption depends on conductivity of the ground. In the hard ground water is absorbed and enters the deeper layers of the ground with difficulty due to low conductivity of the ground. Water flows most intensely through drainage trenches and next to them. These conditions of water flow in trenches form when the ground structure alters and overloads them. The time passing by, cracks, having occurred in the drainage trench, are filled with small ground particles. It influences deterioration of ground water conductivity qualities. In order to improve water runoff from the upper soil layer, natural substances found in nature, if inserted across, above the drain, could help. Using porous substances in order to cover drainage trenches, part of the water would accumulate in newly equipped cross-section drain trenches. Applying such a technology would allow increasing the efficiency of drainage without changing the already laid drainage pipes. Modeling the influence of cross-section drainage trench density on ground water level between drains, it was determined that additional installation could affect ground water level between the cross-section drains trench, the distance being up to 30 meters. When the distance is larger, its impact on the ground water level recession becomes insignificant and reaches only 1-2%... [to full text]
1155

"Ju fler som äger frågan, desto bättre kommer resultatet att bli" : Förskolechefers syn på att utbildningen i förskolan ska vila på vetenskaplig grund och beprövad erfarenhet

Cederholm, Åsa, Mrak, Lina January 2012 (has links)
SAMMANFATTNING ”Ju fler som äger  frågan, desto bättre kommer resultatet att bli” Förskolechefers syn på att utbildningen i förskolan ska vila på vetenskaplig grund och beprövad erfarenhet Antal sidor: 28 Från och med den 1 juli 2011 lyder förskolan under skollagen. Förskolan ses som första steget i utbildningsväsendet och utbildningen ska vila på vetenskaplig grund och beprövad erfarenhet. Studien syftar till att undersöka hur förskolechefer beskriver vetenskaplig grund och beprövad erfarenhet och hur de tänker att begreppen ska implementeras i verksamheten. Våra frågeställningar är: Hur uppfattar förskolecheferna   innebörden av begreppen vetenskaplig grund och beprövad erfarenhet och dess innebörd för den pedagogiska verksamheten?   På vilket sätt uppfattar de att dessa begrepp kan implementeras i verksamheten? För att få svar på våra frågor genomförde vi intervjuer med fyra förskolechefer. Intervjuerna transkriberades och analyserades. Utifrån tolkningar av svaren framkom fyra   områden: Ställningstaganden, Kommunikation/Dialog, Tydligare uppdrag och Dilemman i praktiken. Resultatet av studien visar att det finns en medvetenhet hos förskolecheferna om betydelsen av skollagens skrivning för förskolans verksamhet och status i samhället. Kravet på dokumentation ses som positivt, då förskolan tidigare varit dålig på att dokumentera sin verksamhet och koppla till forskning. Styrdokument och den egna utbildningen anses till stor del stå för den vetenskapliga grunden. Det komplexa är dock att den egna utbildningen upplevs som gammal och det gör implementeringsarbetet av de nya styrdokumenten svårt. En organisation där delaktighet, ett kritiskt förhållningssätt samt tid till diskussion och reflektion får plats är en förutsättning för att implementeringsarbetet ska lyckas. / ABSTRACT "The more people who own the issue, the better the result will be" Pre-school Managers' attitudes toward education in kindergarten, based on scientific basis and proven experience Number of pages: 28 On July 1, 2011 Swedish pre-school became an integral part and are now governed by the   Education Act. Pre-school is seen as the first step in the educational system and education shall be based on scientific basis and proven experience. The purpose of the study is to examine how pedagogical leaders describe scientific basis and proven experience and how   they think that the terms could be implemented in the pre-school practice.  Our queries are:  • What do pedagogical leaders of pre-schools perceiver the terms “scientific basis” and        “proven experience” will mean for the educational activities? • How can these terms be implemented in pre-school practice?   The study was conducted as a series of interviews with four pedagogical leaders of pre-schools. The discussions have been transcribed and analyzed. Based on these interpretations four areas of interest appeared: Standpoints; Communication / Dialogue; A pronounced mission and; Dilemmas in practice. The results acknowledge that pedagogical leaders recognize, not only the importance of   including pre-school as part of the Education Act, but also how the Act influences the pre-school status in society. The requirement for documentation is seen as positive, since pre-school historically has been poor at documenting the practice and subsequent link to research. Curriculums and the pedagogical leaders own education is considered to be the major source of scientific basis. However, here lies a complexity, because many pedagogical leaders own education is perceived as outdated and that makes the implementation work of the new curriculums difficult. An organization which recognizes participation, critical engagement, time for dialogue and reflection would most likely support these fundamentals as a means for the implementation work to succeed.
1156

Resilience to Ecological Change: Contemporary Harvesting and Food-Sharing Dynamics in the K'asho Got'ine Community of Fort Good Hope, Northwest Territories

McMillan, Roger Unknown Date
No description available.
1157

Integrated pest management of Sitona lineatus L. (Coleoptera: Curculionidae) in crops of Pisum sativum L. (Fabales: Fabaceae) in Western Canada

Vankosky, Meghan Ann Unknown Date
No description available.
1158

Effects of forest site preparation methods on carabid beetle (Coleoptera:Carabidae) diversity

Beaudry, Suzanne January 1995 (has links)
The objective was to analyze the effects of logging and prescribed burning on carabid beetles (Coleoptera: Carabidae) at a jack pine stand and white spruce plantations in order to assess short-term impacts of these forestry practices on the diversity of this beetle group. In addition, soil scarification was also included at the jack pine stand. Based on previous reports on forest disturbance influences on carabids, it is hypothesized that short-term effects of studied forestry practices do not reduce carabids' diversity. Four carabid assemblage characteristics were compared: (a) number of catches; (b) dry mass; (c) species richness; and, (d) diversity index. Species responses and dry mass distributions were also investigated. Treatments either increased or maintained studied variables compared with control sites. Diversity indices were highest in burnt-over areas. Similar response patterns of species or groups of species were observed in both forest types. The presence of regenerating sites among the natural landscape increased carabid diversity.
1159

Mapping permafrost and ground-ice related coastal erosion on Herschel Island, southern Beaufort Sea, Yukon Territory, Canada

Lantuit, Hugues January 2004 (has links)
Climate change and warming have been linked to enhanced coastal erosion in the arctic. Specifically, permafrost is believed to be thawing at greater rates, and wave dynamics are expected to increase in intensity. As a result, thermokarst activity, which includes the occurrence of retrogressive thaw slumps, will be more frequent along arctic coasts. / The availability of airborne and spaceborne imagery in the arctic over the last fifty years has made possible the temporal analysis of permafrost and ground ice-related erosion. The objectives of this thesis are (1) the creation of a large scale database for horizontal coastal retreat on Herschel Island for the 1952-2000 timespan, (2) the investigation of retrogressive thaw slump activity over the same period and its relation to coastal erosion, and (3) the elaboration of stereophotogrammetric techniques to investigate retrogressive thaw slump activity volumetrically. Herschel Island, located on the northern coast of the Yukon Territory, was chosen as the study site for this research, because of the widespread presence of retrogressive thaw slumps and the lack of data for coastal erosion during the last fifty years. / Photogrammetric tools were used to create orthorectified and stereo-images of the Island for the years 1952, 1970, 2000 and 2004 from airphoto archives and Ikonos (1 m resolution) imagery. Coastal erosion was found to be stable or declining on Herschel Island except in the vicinity of retrogressive thaw slumps. In addition, retrogressive thaw slumps were identified on the imagery and observed to have increased in frequency for the 1952-2000 period. / Stereophotogrammetric analysis of two retrogressive thaw slumps showed that eroded sediment volumes from these landforms are considerable and should be included in future assessments of sediment release from arctic coasts to the oceanic shelves.
1160

Development of a code of practice for co-disposal to obviate inimical environmental impacts of generated gases and leachates.

Daneel, Richard A. January 1996 (has links)
Despite its phasing out in numerous countries, such as Germany and the U.S.A., co-disposal of hazardous waste with municipal solid waste continues to be widely practised in South Africa. Co-disposal utilises properties and microbial activities in the refuse to attenuate the hazardous waste and thus obviate its environmental impact potential. All landfill operations require careful planning in not only site selection criteria but also the type and amount of various wastes accepted for disposal. It is clear, however, that the practice of co-disposal requires special precautions and management as the methods employed in the landfill operation determine to a large extent the environmental effects and, thus, the public acceptability of the operations. Although co-disposal is not suitable for all industrial wastes the results of recent research efforts, conducted mainly in the U.K., have indicated that, when properly managed, co-disposal can be regarded as a safe and efficient disposal option for many hazardous wastes. Environmental awareness in many European countries ensures that numerous hazardous compounds are either recycled or recovered. Unfortunately, in South Africa the lack of similar concern has resulted in increased concentrations of toxic compounds being co-disposed on a regular basis. Since fundamental studies of this technology, pertaining to South African conditions, have been lacking laboratory models/microcosms were built to address this paucity. Model. To effect the separation of species habitat domains of component species of growth rate-dependent interacting microbial associations responsible for terminal catabolic processes of the refuse fermentation, with retention of overlapping activity domains, and so facilitate examination of species in isolation without violating the integrity of each association, multi-stage models were constructed. The accidental overgassing of the culture with liquid petroleum gas (LPG) effected interesting fermentation balance changes which also emphasised the need for an Anaerobic Bioassay Test to assess the impacts of specific perturbants. Evidence of differential susceptibility of the component species to phenol was demonstrated in this study. Microcosm. A total of 42 refuse packed single-stage glass column bioreactors were commissioned and subjected to phenol and/or anaerobically digested sewage sludge codisposal. The effects of four different operational modes: leachate discard (single elution); leachate recycle; batch; and simulated rain on the co-disposals as well as refuse catabolism per se were examined. The results of these studies indicated that protracted periods of adaption to phenol (1000 and 2000 mg l -1) could have resulted from nutrient (elemental) limitation. Circumstantial evidence was also gained which indicated that the nitrate- and sulphate-reducing bacteria (SRB) were particularly sensitive to the added xenobiotic. Further, without the effective participation of the nitrate- and SRB the active and total fermentation of both the phenol and refuse components were depressed. It was also determined that the operating regime employed was a key factor in refuse degradation although with time, and especially following the phenol resupplementations, the operating conditions played a less significant role. In general, the single elution operated columns demonstrated increased phenol removal rates which were, unfortunately, coincident with low pH values and increased leachate residual phenol concentrations. Leachate recycle, on the other hand, unlike the batch operated columns, facilitated increased pH values and methane evolutions. The simulated rain columns were characterised by rapid washout of the added phenol as well as methanogenic precursors. The sewage sludge co-disposal experiments, likewise, demonstrated that, depending on the sludge:refuse ratio, the operating regime was extremely important in optimising the refuse degradation processes although, in general, leachate recycle appeared to be the most favoured method of operation. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1996.

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