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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.
481

Taktik vid strid i bergsterräng : En jämförelse mellan USA och Sovjets taktik i Afghanistan

Karlsson, Johan January 2009 (has links)
<p>I och med det svenska bidraget till NATO missionen i Afghanistan samt den nyupprättade bergsplutonen på Arméns JägarBataljon i Arvidsjaur så har frågor kring taktik i bergsterräng även blivit aktuellt för Sverige. Då svenska utbildningarna och doktriner i huvudsak saknar problematiseringen kring att strida eller verka i bergsterräng så kan man där av ställa sig frågan hur ska vi få kunskap om detta? Detta arbete syftar därför till att jämföra den av USA använda taktiken i Afghanistans bergsterräng och den Sovjet har använt sig av. Frågan som arbetet försöker besvara är dels vad skillnaden har varit mellan taktiken hos stormakterna samt vad som varit den största framgångsfaktorn och begränsningen i respektive lands konflikt. Arbetet bygger på ett underlag främst från litteratur samt artiklar om operationer genomförda i Afghanistan.</p><p>Arbetets resultat kan sammanfattas med att de faktorer som mest har påverkat dessa länders lösande av uppgift har varit hur ledarskapet har varit inom deras förband, och då främst hur i vilken utsträckning dessa har använt sig av uppdragstaktik. Flexibilitet, samordning av den indirekta elden och valet av understödsförmågor har även dessa varit viktiga faktorer som påverkat lösandet av uppgiften.</p> / <p>Due to the Swedish contribution to the by NATO led International Security Assistance Force (ISAF) in Afghanistan and the newly established Mountain Platoon at the Swedish Army Ranger Batalion in Arvidsjaur have the question about mountain warfare started to be of interest for Sweden. Because of the lack of discussion of mountain warfare and how to act in the mountain terrain in the Swedish military doctrine and education the question is how to get knowledge of this? The purpose of this paper is to compare the tactics used by the U.S. and the Soviets in the mountains of Afghanistan. The question this paper is trying to answer is what the different between the two countries tactics and what have been the most important factor for success and the biggest limitation in the countries tactics in the conflict. The basis for the comparison was received from literature and articles about operations conducted in Afghanistan.</p><p>The results of the essay can be summarized in that the most prominent factor have been the leadership used by the units, and mainly to what extent they have used mission type tactics, Flexibility, coordination of the indirect fire and what support they have chosen to use have also been an important factor that affected the outcome.</p>
482

Groundwater Occurrence of Table Mountain area in Cape Town South Africa.

Wu, Changhong. January 2009 (has links)
<p>Groundwater is an important water resource to be used to supplement the water demand for the City of Cape Town for present and future generations. Understanding the groundwater occurrence of the Table Mountain area is very important for future groundwater exploitation and management. Apart from the sea in the west, Table Mountain is mostly surrounded by the unconsolidated sediments including the Kirstenbosch, Newlands, and Oranjezicht areas. These areas are rich in groundwater resources, like springs / some of them were utilized, others not. However, there are few studies that focused on spring resource in this area. No up to date information is available for spring resources research and relative data is lacking from local research institutions. In fact, some of the spring resources in the Table Mountain area had been extracted and been utilized for local community for many years. Data and information newly obtained from this study about such groundwater resources will help future groundwater development and management. There are at least 13 springs in the selected study area. Those springs were investigated for groundwater occurrence, because spring is an important manifestation of the underlying aquifer through which groundwater dynamics can be detected. The main objective of the study was to sketch a clear picture of groundwater occurrence and to obtain an improved understanding of how geomorphology affects groundwater flow, its manifestation and quality. Water resources management is also important because this kind of water resource can be used to help meet the water demand of this local area in the future. There is relationship between the topographical features of the Table Mountain and spring occurrence. The research area delineated is used to interpret the relationship. Hydro-geochemical analysis is carried out to indicate the chemical components of the groundwater and to understand the groundwater type and water quality of this particular area. Based on the completed analysis and interpretation of factors influencing discharge and recharge, some good results were obtained and useful information is made available for first time.</p>
483

Taktik vid strid i bergsterräng : En jämförelse mellan USA och Sovjets taktik i Afghanistan

Karlsson, Johan January 2009 (has links)
I och med det svenska bidraget till NATO missionen i Afghanistan samt den nyupprättade bergsplutonen på Arméns JägarBataljon i Arvidsjaur så har frågor kring taktik i bergsterräng även blivit aktuellt för Sverige. Då svenska utbildningarna och doktriner i huvudsak saknar problematiseringen kring att strida eller verka i bergsterräng så kan man där av ställa sig frågan hur ska vi få kunskap om detta? Detta arbete syftar därför till att jämföra den av USA använda taktiken i Afghanistans bergsterräng och den Sovjet har använt sig av. Frågan som arbetet försöker besvara är dels vad skillnaden har varit mellan taktiken hos stormakterna samt vad som varit den största framgångsfaktorn och begränsningen i respektive lands konflikt. Arbetet bygger på ett underlag främst från litteratur samt artiklar om operationer genomförda i Afghanistan. Arbetets resultat kan sammanfattas med att de faktorer som mest har påverkat dessa länders lösande av uppgift har varit hur ledarskapet har varit inom deras förband, och då främst hur i vilken utsträckning dessa har använt sig av uppdragstaktik. Flexibilitet, samordning av den indirekta elden och valet av understödsförmågor har även dessa varit viktiga faktorer som påverkat lösandet av uppgiften. / Due to the Swedish contribution to the by NATO led International Security Assistance Force (ISAF) in Afghanistan and the newly established Mountain Platoon at the Swedish Army Ranger Batalion in Arvidsjaur have the question about mountain warfare started to be of interest for Sweden. Because of the lack of discussion of mountain warfare and how to act in the mountain terrain in the Swedish military doctrine and education the question is how to get knowledge of this? The purpose of this paper is to compare the tactics used by the U.S. and the Soviets in the mountains of Afghanistan. The question this paper is trying to answer is what the different between the two countries tactics and what have been the most important factor for success and the biggest limitation in the countries tactics in the conflict. The basis for the comparison was received from literature and articles about operations conducted in Afghanistan. The results of the essay can be summarized in that the most prominent factor have been the leadership used by the units, and mainly to what extent they have used mission type tactics, Flexibility, coordination of the indirect fire and what support they have chosen to use have also been an important factor that affected the outcome.
484

Precipitation estimation in mountainous terrain using multivariate geostatistics

Hevesi, Joseph A. 22 May 1990 (has links)
Estimates of average annual precipitation (AAP) are-needed for hydrologic modeling at Yucca Mtn., Nevada, site of a proposed, high-level nuclear waste repository. Historical precipitation data and station elevation were obtained for stations in southern Nevada and southeastern California. Elevations for 1,531 additional locations were obtained from topographic maps. The sample direct-variogram for the transformed variable TAAP = ln(AAP) * 1000 was fit with an isotropic, spherical model with a small nugget and a range of 190,000 ft. The sample direct-variogram for elevation was fit with an isotropic model with four nested structures (nugget, Gaussian, spherical, and linear) with ranges between 0 and 270,000 ft. There was a significant (p = 0.05, r = 0.75) linear correlation between TAAP and station elevation. The sample cross-variogram for TAAP and elevation was fit with two nested structures (Gaussian, spherical) with ranges from 55,000 to 355,000 ft. Alternate model structures and parameters were compared using cross-validation. Isohyetal maps for average annual precipitation (AAP) were prepared from estimates obtained by kriging and cokriging using the selected models. Isohyets based on the kriging estimates were very smooth, increasing gradually from the southwest to the northeast. Isohyets based on the cokriging estimates and the spatial correlation between AAP and elevation were more irregular and displayed known orographic effects. Indirect confirmation of the cokriging estimates were obtained by comparing isohyets prepared with the cokriging estimates to the boundaries of more densely vegetated and/or forested zones. Estimates for AAP at the repository site were 145 and 165 mm for kriging and cokriging, respectively. Cokriging reduced estimation variances at the repository site by 55% relative to kriging. The effectiveness of an existing network of stations for measuring AAP is evaluated and recommendations are made for optimal locations for additional stations. / Graduation date: 1991
485

Acoustic sounding of snow water equivalent

Kinar, Nicholas John Stanislaus 13 June 2007
An acoustic frequency-swept wave was investigated as a means for determining Snow Water Equivalent (SWE) in cold wind-swept prairie and sub-alpine environments. Building on previous research conducted by investigators who have examined the propagation of sound in snow, digital signal processing was used to determine acoustic pressure wave reflection coefficients at the interfaces between 'layers' indicative of changes in acoustic impedance. Using an iterative approach involving boundary conditions at the interfaces, the depth-integrated SWE was determined using the Berryman equation from porous media physics. Apparatuses used to send and receive sound waves were designed and deployed during the winter season at field sites situated near the city of Saskatoon, Saskatchewan, and in Yoho National Park, British Columbia. Data collected by gravimetric sampling was used as comparison for the SWE values determined by acoustic sounding. The results are encouraging and suggest that this procedure is similar in accuracy to SWE data collected using gravimetric sampling. Further research is required to determine the applicability of this technique for snow situated at other geographic locations.
486

Förfädernas berg? : en tolkning av fornborgen på Halleberg / Mountain of the ancestors? : an interpretation of the hill-fort on Halleberg

Trollklint, Emil January 2011 (has links)
The essay deals with the hill-fort on the mountain Halleberg, Sweden, its wall design, functionality, dating and its possible function as a central location and a place of worship of the ancestors. The Halleberg hill-fort consists of a 1500 meters long at times cohesive stonewalls which together blocked the mountain from its surroundings. Hallberg's natural vertical scree and cliffs along with the masonry blocked the whole mountain from the surroundings. The hill-forts, with few exceptions are largely not investigated archaeologically and its functionality and role in the ancient society is based on outdated research on the subject. The current archaeological interpretation is that hill-forts served as temporary defense in times of unrest or served as center of power for a social elite. The prevailing view in the archaeological sphere is that the hill-forts had a variety of functions and that its functionality and role in ancient society has varied. Halleberg´s strongest wall sections are at the mountain's south-eastern part where the natural driveway, Storgårdsklev is located. Along with the massive masonry of the walls in Bokedalen Storgårdsklev functioned as the hill-forts main entrance. At places along the walls are the remains of what could be interpreted as stacked rocks and possible fire cracked stone. These structural features indicate that the walls were built during the early Iron Age. Very likely has its function like other hill-forts have been varied and changed based on the community, organization and internal and external disturbances. The essay's main interpretation is that the hill-fort served as a defensive fortress. Moreover it is possible that walls of the hill-fort had a symbolic role as a border between two separate rooms in the landscape. The fencing of Halleberg turned the whole mountain to a closed landscape, separated from the surroundings. It may have been a place where people worshiped their ancestors, a place where life's events, life and death was the focus point.
487

Acoustic sounding of snow water equivalent

Kinar, Nicholas John Stanislaus 13 June 2007 (has links)
An acoustic frequency-swept wave was investigated as a means for determining Snow Water Equivalent (SWE) in cold wind-swept prairie and sub-alpine environments. Building on previous research conducted by investigators who have examined the propagation of sound in snow, digital signal processing was used to determine acoustic pressure wave reflection coefficients at the interfaces between 'layers' indicative of changes in acoustic impedance. Using an iterative approach involving boundary conditions at the interfaces, the depth-integrated SWE was determined using the Berryman equation from porous media physics. Apparatuses used to send and receive sound waves were designed and deployed during the winter season at field sites situated near the city of Saskatoon, Saskatchewan, and in Yoho National Park, British Columbia. Data collected by gravimetric sampling was used as comparison for the SWE values determined by acoustic sounding. The results are encouraging and suggest that this procedure is similar in accuracy to SWE data collected using gravimetric sampling. Further research is required to determine the applicability of this technique for snow situated at other geographic locations.
488

Idea and Practice in Master Sheng Yen's "Pure Land on Earth'

Lee, Chih-liang 25 January 2011 (has links)
Humanistic Buddhism in Taiwan has become a mainstream in recent 2 decades. It¡¦s from local form to international organization, and uses the way of commercial management. On the other side, the Buddhist adopt a ¡§inner transformation¡¨ strategy to turn difficult words in the Buddhist Scripture into understandable saying. When Master Sheng Yen was a novice, he had already realized that ¡§the Buddha dharma is so great, but many people misunderstand it and so few people are willing to accept it.¡¨ Therefore, he decided to develop and promote Buddhist higher education. Master Sheng Yen held the religious spirit of universal delivery ,tireless in all his efforts. He established the Dharma Drum Mountain World Center for Buddhist Education in Jinshan Township, Taipei County, in order to practice the Threefold Education¡XExtensive Academic Education, Extensive Public Buddhist Education, and Extensive Social Care Education¡Xwhich is the foundation on which to realize the vision of ¡§uplifting the character of humanity and building a pure land on Earth¡¨. The Master would like to spread the Dharma in language and ideas that people can relate to. For this reason, the Master proposed a series of social movements, hoped to provide concepts and methods applicable in today¡¦s life. These methods include ¡§the Spiritual Environment¡¨,¡¨ Four Kinds of Environmentalism¡¦, ¡§the Fivefold Spiritual Renaissance Campaign¡¨, and ¡§the Six Ethics of the Mind¡¨. The Master is a legendary people. The vision of ¡§uplifting the character of humanity and building a pure land on Earth¡¨ has opened a new sight in Taiwan.
489

Climate and the autumnal moth (Epirrita autumnata) at Mountain Birch (Betula pubecens ssp. czerepanovii) Treelines in northern Sweden.

Young, Amanda B. 16 January 2010 (has links)
The main objectives of this investigation were to determine the impact of climate on mountain birch (Betula pubecens ssp. czerepanovii (Orlova)) growth and to develop a regional chronology of autumnal moth outbreaks. To accomplish the objective, cores of mountain birch were taken from 21 sites in Norrbotten, Sweden. Tree-ring chronologies were developed for each site. Climatic influences were determined by correlating ring widths to climatic variables (average monthly temperature, average monthly precipitation and NAO). Outbreaks were recovered from the ring width indices using the non-host method with Scots pine (Pinus sylvestris (L.)) as the non-host. This method removes the climatic influence on growth to enhance other factors. Patterns of synchrony and regional outbreaks were detected using regression and cluster analysis techniques. The primary climatic influences on the tree ring growth of mountain birch are June and July temperatures; precipitation during October is of secondary importance. Climate explained 46% of yearly tree ring width variation. Outbreaks of the autumnal moth occur at varying time intervals depending on the scale of study. Intervals between outbreaks on the tree level are twice as long as at the plot level. On the regional scale plots within the same valley had more similar outbreak intervals and magnitudes of outbreaks. Elevation is a driver in determining the length of outbreaks and length between outbreaks. The percent monocormicity of a plot is also a determining factor of the length between outbreaks. This study is the first regional scale study on climate and outbreaks of the autumnal moth on mountain birch. The results complement research being conducted on autumnal moth larval densities and will help in modeling and assessing the effects of outbreaks with increasing climatic change.
490

Fire Regimes and Successional Dynamics of Pine and Oak Forests in the Central Appalachian Mountains

Aldrich, Serena Rose 2011 May 1900 (has links)
The role of fire in determining the structure and composition of many forested ecosystems is well documented (e.g. North American boreal forests; piñon-juniper woodlands of the western US). Fire is also believed to be important in temperate forests of eastern North America, but the processes acting here are less clear, particularly in xerophytic forests dominated by yellow pine (Pinus, subgenus Diploxylon Koehne) and oak (Quercus L.). In this study, I use dendroecological techniques to investigate fire history and vegetation dynamics of mixed pine-oak forests in the central Appalachian Mountains of Virginia. The study addresses three objectives: (1) develop a lengthy fire chronology to document fire history beginning in the late presettlement era and extending throughout the period of European settlement, industrialization and modern fire exclusion; (2) explore fire-climate relationships; and (3) investigate vegetation dynamics in relation to fire occurrence. The study was conducted on three study sites within the George Washington National Forest. I used fire-scarred cross-sections from yellow pine trees to document fire history. Fire-climate relationships were investigated for each study site individually and all sites combined using superposed epoch analysis (SEA). Fire-history information was coupled with dendroecological data on age structure to explore stand development in relation to fire occurrence. Results of fire history analysis reveal a long history of frequent fire with little temporal variation despite changes in land use history. Mean fire intervals (MFI) ranged from 3.7–17.4 years. The most important change in the fire regime was the initiation of fire suppression in the early twentieth century. Results of SEA show that periodic droughts may be important drivers of fire activity. Drought the year of fire was important at two of the three study sites and when all sites were combined. Results of age structure indicate that vegetation development was clearly influenced by fire. Frequent burning maintained populations of yellow pine throughout the period of study until fire suppression allowed fire-sensitive hardwood trees and shrubs to establish. It is clear from this study that continued fire suppression will likely result in fire-tolerant pines and oaks being replaced by more mesophytic trees and shrubs.

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