The engineering properties of waste spoil from phosphate mines in Southeastern Idaho were determined through field and laboratory testing. The testing included compaction tests, grain size analysis, powder x-ray defraction tests, permeability tests, compression tests, triaxial and direct shear strength tests, and nutrient analyses. Based on these tests, the slope stability and settlement characteristics of phosphate spoil dumps were investigated. The study showed that the foundation is an important component of the stability of a spoil dump. Hypothetical examples were used to illustrate possible modes of foundation failures. Such failures might occur when weak foundation soils exist or when there is a lack of embankment-foundation preparation prior to the disposal of waste material. When considering failures through only the middle waste shale embankment material, the study showed that dumps constructed by end-dumping the spoil material over angle of repose embankments or by scraper filling the material in horizontal lifts will be adequately safe against slope failure if: o Embankment slopes are graded to 21/2 horizontal to 1 vertical or flatter. o Proper precautions are taken to prevent the build-up of a phreatic surface near the top of the embankment. The study also showed that post construction settlement in spoil dumps can be attributed to: o A slow continuing settlement which is linear with the log of time. o Saturation collapse settlement which occurs with increases in the moisture contents. Post construction settlement in spoil dumps is caused principally by increases in the moisture content in layers of middle waste shales and soft cherts. A rationale method for predicting magnitudes of post construction settlement in spoil dumps was also developed as part of this study.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第21330号 / 理博第4426号 / 新制||理||1636(附属図書館) / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)教授 井口 正人, 教授 福田 洋一, 教授 大倉 敬宏 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

Limited knowledge exists of the terrain variables that have an influence on gopher tortoise (Gopherus polyphemus) burrow locations. Previous studies suggest that terrain features may play a role in preference of burrow location. LiDAR- (Light Detection and Ranging) derived terrain features can be evaluated through GIS (Geographic Information System) analysis at a fine spatial scale. LiDAR data acquired at 0.5 meter post spacing over three locations on Camp Shelby Joint Forces Training Center, MS were used to develop DTMs (Digital Terrain Models) for use in burrow site characterization. Terrain variables (e.g. elevation, slope, aspect) were developed from the LiDAR DTM in ArcGIS. Burrows and randomly allocated non-burrow points were used in logistic regression analysis to model the relationship between burrow occurrence and terrain features. Four models correctly classified more than 83% of the burrow locations. The R2 were 34.83%, 49.31%, 28.09%, and 31.51%.

The role of topography on the spatial distribution of tornadoes was assessed through geospatial and statistical techniques. A 100-m digital elevation model was used to create slope, aspect, and surface roughness maps; and; tornado beginning and ending points and paths were used to extract terrain information. Tornado touchdowns, liftoffs, paths, and path-land angles were examined to determine whether tornado paths occur more frequently in or along certain terrain or slopes. Statistical analyses, such as bootstrapping, were used to analyze tornado touchdowns, liftoffs and paths and path-relative terrain angles. Results show that tornado paths are more common with downhill-movement. Tornadoes are not as likely to move uphill because the 73.6 percent northeast path bias represents the highest frequencies of path-angles. Tornado touchdowns and paths occur more often in smooth terrain, rather than rough terrain. Complex topographic variability seems to not have an effect on the spatial distribution of tornadoes.

No description available.

More than 100 landslides have been mapped along the southeast flank of the Uinta Mountains. Large landslide deposits are up to 4.6 kilometers long and have an area of approximately 5-9 km². Landslide types include multiple and successive rock slumps, debris slumps and debris flows. Most landslides have a main head scarp in the Bishop Conglomerate and the large landslides have many minor scarps. Multiple slump blocks are manifest by repeated transverse ridges and trenches in the head area of some landslides. Most body and toe areas are deeply incised by gully erosion (up to 91 meters deep) and drainages are well developed with little ponding. Detailed mapping of the large landslides shows that the deposits are an accumulation of successive slope failures that have continually eroded the landscape over time. Many landslides in the area appear to be inactive and dormant but slopes may continue to fail particularly if landslides are disturbed. A Geographic Information System (GIS) was used to analyse slope failing factors and the main factor that seems to have contributed to slope failure is the presence of abundant shale-rich, weak bedrock capped with the thick and fairly resistant Bishop Conglomerate. Slopes are further destabilized as water percolates down through the porous Bishop Conglomerate. Eventually the water meets underlying shale-rich bedrock where it is channelled near this contact until it emerges as springs. This groundwater flow likely reduces shear strength of the shale-rich substrate and of some of the finer grained layers in the Bishop Conglomerate. Other important slope failure factors include the removal of easily erodable Mesozoic shales from beneath the more-resistant Bishop Conglomerate, headward gully erosion, bedrock dip and slope aspect.

Speech recognition threshold (SRT) is an important clinical measure that validates the pure-tone average (PTA), assists in diagnosis and prognosis of hearing and hearing impairment, and helps identify non-organic hearing impairment. Few published, recorded, and standardized materials exist in languages other than English, which results in audiologists testing individuals using materials developed in a non-native language. Research shows that this is problematic, as certain criterion for SRT testing are not met. Thus, performance may reflect test-language deficiency rather than hearing impairment. Currently, there are no known published materials for use in measuring the SRT in individuals whose native language is Tongan. The purpose of this project was to record and develop psychometrically equivalent words in Tongan for measuring the SRT. This study identified 28 trisyllabic words that were relatively homogenous in relation to audibility and psychometric function slope. The intensity of these 28 words was adjusted to equate 50% threshold performance for each word with the mean PTA (5.92 dB HL) for the twenty normally hearing participants. These materials were digitally recorded onto compact disc for distribution and use for SRT testing in Tongan.

Internal waves exist everywhere in stratified fluids - fluids whose density changes with depth. The two largest bodies of stratified fluid are the atmosphere and ocean. Internal waves are generated from a variety of mechanisms. One common mechanism is wind forcing over repeated sinusoidal topography, like a series of hills. When modeling these waves, linear theory has been employed due to its ease and low computational cost. However, recent research has shown that non-linear effects, such as boundary layer separation, may have a dramatic impact on wave generation. This research has consisted of experimentation on sloped, sinusoidal hills. As of yet, no experimental research has been done to characterize internal wave generation when repeated sinusoidal hills lie on a sloped surface such as a continental slope or a foothill. In order to perform this experiment, a laboratory was built which employed the synthetic schlieren method of wave visualization. Measurements were taken to find wind speed, boundary layer thickness, and density perturbation. From these data, an analysis was performed on wave propagation angle, wave amplitude, and pressure drag. The result of the analysis shows that when wind blows across a series of sloped sinusoidal hills, fluid becomes trapped in the troughs of the hills resulting in a lower apparent forcing amplitude. The generated waves contain less energy than linear predictions. Additionally, the sloped hills produce waves which propagate at an angle away from the viewer. A necessary correction, which shifts from the reference frame of the observer to the reference plane of the waves is described. When this correction is applied, it is shown that linear theory may only be applied for low Froude numbers. At high Froude numbers, the effect of the boundary layer is great enough that the wave characteristics deviate significantly from linear theory predictions. The analyzed data agrees well with previous studies which show a similar deviation from linear theory.

The mining industry contributes to enormous amounts of waste all over the world, which places high demands on tailings dams. In Sweden, there are strict regulations regarding the management and treatment of tailings dams, but some dams that were built before these regulations existed still pose a threat to the environment. Lilla Bredsjön in Dalarna, Sweden, is an example of an old tailings dam that has not been treated properly. Boliden, which is the owner of the dam, and the county board of Dalarna are currently in meetings regarding the responsibilities of old polluted sites in Garpenberg, where Lilla Bredsjön is included. This study aims to investigate possible remediation measures of the dams at Lilla Bredsjön in order to achieve long- term stability upon closure of the facility. Lilla Bredsjön is 350 000 m2 large and contains three impoundments; dam 1 to the east, dam 2 to the south and dam 3 to the north. Dam 1 is seven meters at its highest point whereas dam 2 and 3 both are three meters high. All of the dams are classified to a consequence level of 3, meaning that the consequences in case of a failure would be negligible. They are built using the centerline method with impermeable cores of moraine. The tailings are partly covered with sludge mixed with biomass ash, but no proper closure method have been implemented. A geotechnical investigation was conducted to obtain more information about the geometry, construction and foundation of each dam. It could be observed that dam 1 consisted of a moraine core and support fill, both constructed using the Christmas tree principle. Dam 2 consisted of a coarse and fine filter in the upstream part of the dam, whereas the rest of the dam consisted of a moraine core. Dam 3 consisted of tailings and a moraine core, and was like dam 1 also constructed using the Christmas tree principle. The downstream slopes of all dams are moreover very steep with slope angles of approximately 34o. Seepage and stability calculations were therefore performed in the software GeoStudio. In GeoStudio, two different analysis tools were used; SEEP/W to calculate seepage and SLOPE/W to calculate slope stability. Four hydraulic load cases were analyzed in the calculations: present conditions, flooded conditions, potential maximum seepage and present conditions with lower permeability of the tailings. The result shows that all of the dams are unstable in their present con- ditions, both with original and lower permeability of the tailings, as well as at flooded conditions. The required safety factor is however fulfilled at potential maximum seepage. The stability highly depends on the pore pressure inside the dams, which in turn depends on the choice of closure method. Based on the result from the stability calculations it can be concluded that if a dry cover is chosen as the closure method, it will probably be enough to reinforce the existing dams to achieve long-term stability. If, on the other hand, a raised groundwater level is chosen, more extensive solutions in terms of for example completely new impoundments directly downstream of the existing ones are most likely needed. Before a decision regarding the closure method is taken, it is hence very difficult to come to a conclusion regarding suitable remediation measures of the dams. / Gruvindustrin bidrar med enorma mängder avfall över hela världen, vilket ställer höga krav på gruvdammar. I Sverige finns det strikta förordningar gällande hanteringen och efterbehandlingen av gruvdammar, men en del dammar som byggdes innan dessa förordningar existerade utgör fortfarande ett hot mot miljön. Lilla Bredsjön i Dalarna är ett exempel på en gammal gruvdamm som inte blivit efterbehandlad tillräckligt. Boliden, som äger dammen, har möten med Länsstyelssen Dalarna angående ansvarsförhållanden gällande gamla förorenade områden i Garpenberg där även Lilla Bredsjön ingår. Denna studie syftar till att undersöka möjliga efterbehandlingsmetoder av dammarna vid Lilla Bredsjön för att uppnå långtidsstabilitet i samband med nedläggning av anläggningen. Lilla Bredsjön är 350 000 m2 stor och består av tre uppdämningar; damm 1 i öst, damm 2 i söder och damm 3 i norr. Damm 1 är sju meter som högst medan damm 2 och 3 båda är tre meter höga. Samtliga dammar är klassificerade till konsekvensklass 3, vilket betyder att konsekvenserna i händelse av ett dammbrott är försumbara. Dammarna är byggda med uppåtmetoden och har tätkärnor av morän. Magasinet är delvis täckt med slam utblandat med biobränsleaska, men ingen riktig efterbehandling har utförts. En geoteknisk undersökning genomfördes för att erhålla mer information om geometrin, konstruktionen och grundläggningen av varje damm. Det observerades att damm 1 består av en tätkärna av morän samt stödfyllning som båda konstruerades med julgransprincipen. Damm 2 består av ett grov- och finfilter i uppströmsdelen av dammen medan resten av dammen består av en tätkärna av morän. Damm 3 består av anrikningssand och en tätkärna av morän, och var liksom damm 1 konstruerad med julgransprincipen. Nedströmsslänterna på alla dammar är väldigt branta med en vinkel på ungefär 34o. Genomströmnings- och stabilitetsberäkningar genomfördes därför i programmet GeoStudio. I GeoStudio användes två olika verktyg; SEEP/W för att beräkna genomströmning och SLOPE/W för att beräkna släntstabilitet. Fyra olika hydrauliska belastningsfall analyserades i beräkningarna: normalfallet, överdämning, dimensionerat läckage och normalfallet med lägre permeabilitet på anrikningssanden. Resultatet visar på att samtliga dammar är instabila i deras nuvarande skick, beräknat på normalfallet med både ursprunglig och lägre permeabilitet på anrikningssanden, samt vid överdämning. Den erforderliga säkerhetsfaktorn är däremot uppfylld vid dimensionerat läckage. Stabiliteten är starkt beroende av portrycket inuti dammarna, vilket i sin tur är beroende av vilken efterbehandlingsmetod som väljs för magasinet. Baserat på resultatet från stabilitetsberäkningarna kan det konstateras att om torrtäckning väljs som efterbehandlingsmetod så räcker det förmodligen med att förstärka nuvarande dammar för att uppnå långtidsstabilitet. Om, å andra sidan, en förhöjd grundvattennivå väljs behövs med största sannolikhet en mer omfattande lösning, till exempel helt nya dammar direkt nedströms de nuvarande. Innan ett beslut gällande efterbehandlingsmetod av magasinet har tagits är det alltså väldigt svårt att dra en slutsats gällande den mest lämpliga efterbehandlingsmetoden av dammarna.

This report targets a specific problem for recommender algorithms which is the new item problem and propose a method with sentiment analysis as the main tool. Collaborative filtering algorithms base their predictions on a database with users and their corresponding ratings to items. The new item problem occurs when a new item is introduced in the database because the item has no ratings. The item will therefore be unavailable as a recommendation for the users until it has gathered some ratings. Products that can be rated by users in the online community often has experts that get access to these products before its release date for the consumers, this can be taken advantage of in recommender systems. The experts can be used as initial guides for predictions. The method that is used in this report relies on sentiment analysis to translate written reviews by experts into a rating based on the sentiment of the text. This way when a new item is added it is also added with the ratings of experts in the field. The result from this study shows that the recommender algorithm slope one can generate more reliable recommendations with a group of expert users than without when a new item is added to the database. The expert users that is added must have ratings for other items as well as the ratings for the new item to get more accurate recommendations. / Denna rapport studerar påverkan av problemet med nya objekt i rekommendationsalgoritmen Slope One och en metod föreslås i rapporten för att lösa det specifika problemet. Problemet uppstår när ett nytt objekt läggs till i en databas då det inte finns några betyg som getts till objektet/produkten. Då rekommendationsalgoritmer som Slope One baserar sina rekommendationer på relationerna mellan användares betyg av filmer så blir träffsäkerheten låg för en rekommendation av en film med få betyg. Metoden som föreslås i rapporten involverar attitydanalys som det huvudsakliga verktyget för att få information som kan ersätta faktiska betyg som användare gett en produkt. När produkter kan bli betygsatta av användare på olika forum på internet så finns det ofta experter får tillgång till produkten innan den släpps till omvärlden, den information som dessa experter har kan användas för att fylla det informationsgap som finns när ett nytt objekt läggs till. Dessa experter kommer då initiellt att användas som guide för rekomendationssystemet. Så när ett nytt objekt läggs till så görs det tillsammans med betyg från experter för att få mer träffsäkra rekomendationer. Resultatet från denna studie visar att Slope One genererar mer träffsäkra rekommendationer då en ny produkt läggs till i databasen med ett antal betyg som genererats genom attitydanalysanalys på experters textrecensioner. Det är värt att notera att ett betyg enbart för dessa expertanvändare inte håller utan experterna måste ha betyg av andra produkter inom samma område för kunna influera rekommendationer för den nya produkten.