Academic literature on the topic 'MDD UCS'
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Journal articles on the topic "MDD UCS"
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Taffese, Woubishet Zewdu, and Kassahun Admassu Abegaz. "Artificial Intelligence for Prediction of Physical and Mechanical Properties of Stabilized Soil for Affordable Housing." Applied Sciences 11, no. 16 (2021): 7503. http://dx.doi.org/10.3390/app11167503.
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Soil stabilization is the alteration of physicomechanical properties of soils to meet specific engineering requirements of problematic soils. Laboratory examination of soils is well recognized as appropriate for examining the engineering properties of stabilized soils; however, they are labor-intensive, time-consuming, and expensive. In this work, four artificial intelligence based models (OMC-EM, MDD-EM, UCS-EM+, and UCS-EM−) to predict the optimum moisture content (OMC), maximum dry density (MDD), and unconfined compressive strength (UCS) are developed. Experimental data covering a wide range of stabilized soils were collected from previously published works. The OMC-EM, MDD-EM, and UCS-EM− models employed seven features that describe the proportion and types of stabilized soils, Atterberg limits, and classification groups of soils. The UCS-EM+ model, besides the seven features, employs two more features describing the compaction properties (OMC and MDD). An optimizable ensemble method is used to fit the data. The model evaluation confirms that the developed three models (OMC-EM, MDD-EM, and UCS-EM+) perform reasonably well. The weak performance of UCS-EM− model validates that the features OMC and MDD have substantial significance in predicting the UCS. The performance comparison of all the developed ensemble models with the artificial neural network ones confirmed the prediction superiority of the ensemble models.
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Kartika, S., L. A. Asiyanthi, R. R. Irwan, and A. Hidayat. "Strength Behaviour of Sugarcane Bagasse Ash Treated Sewage Sludge-Soil Mixture." IOP Conference Series: Earth and Environmental Science 1117, no. 1 (2022): 012049. http://dx.doi.org/10.1088/1755-1315/1117/1/012049.
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Abstract Laboratory tests were conducted on sugarcane bagasse ash treated sewage sludge-soil mixture with 5%, 10% and 30% bagasse ash to assess its strength behaviour. Unconfined compressive strength (UCS) was performed to observed influence of bagasse ash content (BAC), curing time, water content on value of UCS and axial strain. Soil sample were prepared using standard proctor at 60% of optimum water content. Results recorded value of UCS reached peaked at 20% BAC and then dropped by 46% at 30% BAC. Axial strain increased for every additional BAC. Result shown curing period influence UCS, as curing time longer the value of UCS also rose. Other findings of this study were BAC affected maximum dry density (MDD), 5% BAC and 10% BAC improved MDD but 20% BAC and 30% BAC would reduce value UCS. Finally, it could be concluded 20% BAC was the optimum content to get the optimal UCS improvement of sewage sludge-soil.
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Kormu, Solomon, Alemineh Sorsa, and Shelema Amena. "Correlation of Unconfined Compressive Strength (UCS) with Compaction Characteristics of Soils in Burayu Town." Advances in Materials Science and Engineering 2022 (October 25, 2022): 1–8. http://dx.doi.org/10.1155/2022/1548272.
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The unconfined compressive strength is the most widely used parameter to measure the strength of the subgrade or foundation soil for cohesive soils. Due to its time-consuming and cost-effective nature, most of the time-correlation equations have been used to correlate unconfined compressive strength with compaction parameters and soil index properties. The current study was conducted in Burayu town where fifty soil samples were collected and experimental geotechnical soil tests were carried out based on the American Society for Testing and Materials (ASTM) standards. The correlation and regression analyses were done using the experimental results obtained for unconfined compressive strength (UCS) and compaction characteristics. The regression analysis resulted in a fair coefficient of correlation of 0.61 and 0.78 for single linear regression of UCS with maximum dry density (MDD) and optimum moisture content (OMC), respectively, while R2 = 0.83 for multiple linear regression analysis of UCS with MDD and OMC. After further emphasis, the equation developed using multiple linear regression (UCS = −3105 + 1625 MDD + 40.9 OMC, R2 = 0.83) which was chosen as a prediction equation. After validation of the established model using control tests, the statistical regression analysis shows that the correlation is 97% accurate in the UCS determination for multiple regression analysis. This implies that the established model could be used to predict the UCS in the study area.
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Phoak, Samnang, Ya-Sheng Luo, Sheng-Nan Li, and Qian Yin. "Influence of Submergence on Stabilization of Loess in Shaanxi Province by Adding Fly Ash." Applied Sciences 9, no. 1 (2018): 68. http://dx.doi.org/10.3390/app9010068.
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In this study, the influence of fly ash (FA) content (0%, 10%, 20%, and 30%) on the alteration in the physical and mechanical parameters of loess is investigated. The influences of curing time (0, 14, and 28 days) and submergence and non-submergence conditions are analyzed as well. Analysis considers the variation in Atterberg limits (liquid limit, plastic limit, and plasticity index), compaction parameters (optimum moisture content (OMC), and maximum dry density (MDD)), unconfined compressive strength (UCS) stress, UCS strain, California bearing ratio (CBR) value, and swell potential. Results show that the application of FA-stabilized loess (FASL) is effective. Specifically, the MDD decreases and the OMC increases, the UCS stress increases and the UCS strain decreases, the CBR value improves and the swell potential declines, but Atterberg limits are insignificantly changed by the increase in the FA ratio compared with those of untreated loess. The UCS stress and CBR value are improved with the increase in curing time, whereas the UCS strain is negligible. FASL under submergence condition plays an important role in improving the effect of FA on the UCS stress and CBR value compared with that under non-submergence condition. The UCS stress and CBR value are more increased and more decreased than the UCS strain in submerged samples. Therefore, the application of FASL in flood areas is important for obtaining sustainable construction materials and ensuring environmental protection.
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Razali, Roslizayati. "Experimental Study on Mechanical Behavior of Laterite Soil Treated with Quicklime." Journal of Mechanical Engineering SI 11, no. 1 (2022): 109–22. http://dx.doi.org/10.24191/jmeche.v11i1.23592.
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The present study examines the effect of lime stabilisation on the mechanical properties of laterite soil. Compaction tests were performed in order to obtain optimum moisture content (OMC) and maximum dry density (MDD) for untreated and lime treated laterite soil. A series of Unconfined compressive strength (UCS) tests were carried out on the specimen containing different percentages of lime. In preparing test specimens, laterite soil was initially compacted at their respective OMC and MDD conditions and allowed to cure for 0, 3, 7, 14 and 28 days before being tested. Results for the standard compaction test show an increasing trend for optimum moisture content (OMC), whereas maximum dry density (MDD) decreased as the concentration of lime increased. On the other hand, UCS results indicated that all percentages of lime treated laterite increased in strength with the curing period.
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Liang, Chuanyang, Yuedong Wu, Jian Liu, et al. "Effect of Expanded Polystyrene Particle Size on Engineering Properties of Clayey Soil." Advances in Civil Engineering 2021 (September 6, 2021): 1–10. http://dx.doi.org/10.1155/2021/9951915.
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The particle size of expanded polystyrene (EPS) has an effect on engineering properties of EPS-clay blends. However, the effect of differences between EPS particle size groups subdivided within 1–3 mm on engineering properties is usually ignored. In this study, different particle sizes of EPS pellets have been considered to separately investigate the effect on the optimum water content (OWC), maximum dry density (MDD), unconfined compressive strength (UCS), ductility, coefficient of permeability, and compression index of EPS-clay blends. Results show that the MDD, ductility, hydraulic conductivity, and compression index of EPS-clay blends do not increase with the increase in the EPS particle size in the range of 0.3–3 mm, while the OWC and UCS do not decrease. For a given EPS content, among samples with the EPS particle size of 0.3–1 mm, 1-2 mm, and 2-3 mm, the MDD and UCS of EPS-clay blends with 1-2 mm in EPS particle size are the largest, while the OWC, ductility, coefficient of permeability, and compression index are the smallest. Microstructure analyses reveal that, for samples with the EPS particle size of 1-2 mm, the pore volume is lower and the microstructure is denser, which are the main reasons why the EPS particle size can influence engineering properties of EPS-clay blends.
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Ogboin, Amadise S., Nwaobakata Chukwuemeka, and Charles Kennedy. "Efficiency of Costus Lateriflorus Bagasse Fiber and Cement Composite as Soil Stabilizer for Road Pavement." Scholars Journal of Engineering and Technology 10, no. 4 (2022): 35–41. http://dx.doi.org/10.36347/sjet.2022.v10i04.002.
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This study investigated the effect of costus lateriflorus bagasse fiber and cement composites on extensive soil compaction. Laterite and clay samples from Ubeta-Ula-Ubie Road at Ahoada West LGA in Rivers, Nigeria were prepared and analyzed for changes in maximum dry density (MDD), Optimum moisture content (OMC), consistency limits, and California bearing ratio (CBR) and unconfined compressive strength (UCS), maximum dry density (MDD), liquid limit (LL), and plasticity index (PI) of laterite and stabilized clay decreased with increasing proportion of bass fiber composites, while optimum moisture content (OMC), plastic limit (PL), and unconfined compressive strength (UCS) increases with the proportion of bagasse fiber. This study found that proper ratio of bagasse fiber content in soil stabilization will improve soil properties suitable for paving and road construction. Bagasse fiber has a relatively better performance in lateritic soil than in clay with the optimum ratio of cement composition of 0.75% and 7.5%.
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Senagah, Amenjor, and Preetpal Singh. "A Review on Stabilizing Clayey Soil Using Waste Materials." IOP Conference Series: Earth and Environmental Science 1327, no. 1 (2024): 012001. http://dx.doi.org/10.1088/1755-1315/1327/1/012001.
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Abstract Infrastructural development on unstable clayey soil has resulted to the damage of buildings and roads, the loss of lives, and financial instability in many projects including both vertical and horizontal structures due to the incapability of clayey soil to withstand certain magnitude of loadings. Furthermore, the deposit of materials that are left-over in open areas has also become an environmental challenge for residents in many communities. This review elaborates on the effect of waste materials—SDA (sawdust ash), FA (fly ash), and RHA (rice hush ash)—on the shearing strength of clayey soil as agents for stabilization. The study covers significant books on stabilizing clayey soil with additives as well as high indexed research articles that were published from 1998 to 2023. The findings show that, mixing the ash of sawdust with natural clay soil at the peak values of four (4) percent to seven point five (7.5) percent carries up the UCS (Unconfined Compressive Strength), the MDD (Maximum Dry Density), the CBR (California Bearing Ratio), and lowers the soil’s swelling, Optimum Water Content or OMC and Liquid Limit (LL). Similarly, the mixture of FA and clay soil at the optimum values ranging from 9 to 25%, raises the clayey soil’s UCS, MDD, and CBR while lowering its swelling potential, OMC, and LL. Additionally, the UCS, MDD and CBR increases, and the swelling, OMC, and LL reduce at the optimum value of added rice hush ash ranging from 10 to 20%. Thus, it is established that the addition of sawdust, fly, and rice hush can enhance clayey soil’s engineering properties.
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Chukwuemeka, Nwaobakata, Amadise S. Ogboin, and Charles Kennedy. "Performance of Costus Lateriflorus Bagasse Ash and Cement as Stabilization Materials for Soil in Road Construction." Saudi Journal of Civil Engineering 6, no. 4 (2022): 57–63. http://dx.doi.org/10.36348/sjce.2022.v06i04.001.
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The study investigated the performance of Costus lateriflorus bagasse ash and cement composite for stabilization of Laterite and clay soils from Ubeta-Ula-Ubie road in Ahoada West LGA of Rivers state, Nigeria. The soil samples were prepared and tested for variations in maximum dry density (MDD), optimum moisture content (OMC), consistency limits, California bearing ratio (CBR) and unconfined compressive strength (UCS), maximum dry density (MDD), liquid limit (LL) and plasticity index (PI) of the stabilized laterite and clay soils decreased with increasing percentage of the bagasse ash composite, while optimum moisture content (OMC), plastic limit (PL) and unconfined compressive strength (UCS) were increased with the proportion of bagasse ash. This study establishes that an appropriate proportion of bagasse ash content in soil stabilization would enhance the properties of soil suitable for pavement and road construction. Comparatively, bagasse ash performed better in Laterite soil than clay soil at optimum proportion of 0.75% and 7.5% cement composition.
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Chukwuemeka, Nwaobakata, Amadise S. Ogboin, and Charles Kennedy. "Performance of Costus Lateriflorus Bagasse Ash and Cement as Stabilization Materials for Soil in Road Construction." Saudi Journal of Civil Engineering 6, no. 4 (2022): 57–63. http://dx.doi.org/10.36348/sjce.2022.v06i04.001.
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The study investigated the performance of Costus lateriflorus bagasse ash and cement composite for stabilization of Laterite and clay soils from Ubeta-Ula-Ubie road in Ahoada West LGA of Rivers state, Nigeria. The soil samples were prepared and tested for variations in maximum dry density (MDD), optimum moisture content (OMC), consistency limits, California bearing ratio (CBR) and unconfined compressive strength (UCS), maximum dry density (MDD), liquid limit (LL) and plasticity index (PI) of the stabilized laterite and clay soils decreased with increasing percentage of the bagasse ash composite, while optimum moisture content (OMC), plastic limit (PL) and unconfined compressive strength (UCS) were increased with the proportion of bagasse ash. This study establishes that an appropriate proportion of bagasse ash content in soil stabilization would enhance the properties of soil suitable for pavement and road construction. Comparatively, bagasse ash performed better in Laterite soil than clay soil at optimum proportion of 0.75% and 7.5% cement composition.
Dissertations / Theses on the topic "MDD UCS"
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Bååth, Maya, and Frida Jonsson. "Utvärdering av höjdosäkerhet i digital terrängmodell framtagen med fotografier infångade med DJI Phantom 4 RTK." Thesis, Högskolan i Gävle, Samhällsbyggnad, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-32797.
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Att använda obemannade flygfarkoster, även kallat UAS (unmanned aerial systems), i karterings- och modelleringssyften har blivit en välanvänd metod de senaste åren. Mycket på grund av den tekniska utvecklingen som till stor del automatiserat processen med att framställa höjdmodeller och ortofoton. Inom ramen för denna studie kommer vi att titta närmare på hur olika faktorer påverkar höjdosäkerheten hos en höjdmodell framställd med data insamlat med en Real-Time Kinetic-UAS (RTK-UAS). Studien kommer dels att undersöka hur stor osäkerheten blir om endast den integrerade nätverks-RTK:n (NRTK) används vid georeferering av flygbilderna, dels att se hur stor påverkan adderade markstödpunkter har på osäkerheten. Studien kommer även undersöka hur stor påverkan flyghöjden har på osäkerheten genom att jämföra data från två flyghöjder: 100 m och 50 m. Det sista studien som undersöks är vilken inverkan snedbilder har på osäkerheten. Detta genom att jämföra en flygning där lodbilder tagits med en flygning där kameran har haft en vinkling på 60° från lod. Studien genomfördes med hjälp av Falun kommuns mättekniker som manövrerade UAS:en. För att kunna testa markstödpunkternas inverkan på osäkerheten mättes nio punkter in. Även kontrollprofiler mättes för att kunna kontrollera höjdmodellerna som producerades. Totalt genomfördes 3 olika flygningar: 100 m med lodbilder, 50 m med lodbilder samt 50 m med snedbilder. De insamlade fotografierna importerades till programvaran Agisoft Metashape där de georefererades med olika metoder. För att undersöka hur markstödpunkter påverkar osäkerheten genomfördes fem olika georefereringsmetoder av fotografierna tagna på 100 m flyghöjd med olika antal markstödpunkter i varje. RMS-värdet varierade från 0,060 m för NRTK + 1 GCP till 0,068 m för NRTK+2 GCP som fick den högsta osäkerheten.Undersökningen av flyghöjder visade att en lägre flyghöjd har en tydlig effekt på mätosäkerheten. En minskning av RMS-värdet sågs när 50 m flyghöjd användes jämfört med när 100 m flyghöjd användes. Användningen av snedbilder gav ingen tydlig effekt på mätosäkerheten. RMS-värdet blev 0,014 m då lodbilder användes och 0,017 m då snedbilder användes. Snedbildernas resultat försämrades något på grund av den adderade höjden från gräset, så på endast hårdgjorda ytor blir RMS-värdet från snedbildsflygningen noterbart lägre än RMS-värdet från lodbildsflygningen.<br>The technology of Unmanned Aerial Systems (UAS) has gained popularity as atool for mapping and modeling applications in recent years. This is mainly dueto the technological developments that have largely automated the process ofproducing digital elevation models (DEMs) and orthophotos. This study investigates the factors that effect the height uncertainty in anelevation model that is produced with data collected with a NRTK-UAS(Network Real-Time Kinematic UAS). We also evaluate two differentscenarios i.e. how the uncertainty is affected by using only NRTK-UAS andthe effect of adding ground control points (GCPs) to NRTK-UAS. It is alsoinvestigated how the flying height and using oblique images affect the DEMuncertainty. This will be assessed by comparing two flights i.e. by capturingnadiral and oblique images. The oblique images were captured at a 60° angle. The study was realised with help from the surveying engineer of Falunmunicipality, who maneuvered the UAS. The study area was around three anda half ha and consisted mainly of park. To be able to test differentgeoreferencing methods GCP:s were surveyed, as well as control profiles thatserved as a reference for investigating the uncertainty of the elevation model.There were totally 3 different flying methods tested: 100 m with nadiralorientation, 50 m with nadiral orientation and 50 m with oblige orientation. The acquired data was processed in the software Agisoft Metashape, where itwas georeferenced with different above-mentioned methods. To be able toexamine which impact GCP has on the uncertainty, five different sets withdifferent number of GCP were made with the photos captured from 100 mflying height. The RMS value varied from 0,060 m for NRTK+1 GCP whichhad the lowest RMS value to 0,068 m for NRTK+2 GCP which had the highest RMS value. We used the combination of NRTK-UAS and GCPs for testing the impact offlying height on the uncertainty. The flying heights 100 m and 50 m wascompared. A decrease of the uncertainty was observed when the flying heightwas 50 m instead of 100 m. Our results show that the RMS-value increased from 0,014 m to 0,017 musing nadiral and oblique images, respectively. The difference is too small tobe able to draw a conclusion. The results for the oblique images improvedwhen only hard surfaces such as asphalt, concrete etc. were observed.
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Hedqvist, Emma, and Daniel Jakobsson. "Uppdatering av nationella höjdmodellen över begränsade områden med hjälp av UAS." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-22073.
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I det här examensarbetet undersöks möjligheten att använda UAS över begränsade områden när den nationella höjdmodellen skapad av Lantmäteriet ska uppdateras. Ämnet var ett förslag från Lantmäteriet och huvudsyftet var att testa om UAS kan användas som komplettering till traditionell flygfotografering. Det blir allt vanligare att använda UAS inom till exempel geomatiken, eftersom det är ett bra verktyg när ett snabbt och effektivt resultat krävs. Lantmäteriet använder flygburen laserskanning vid genereringen av nationella höjdmodellen och den uppdateras med traditionell flygfotografering. Andra aspekter som undersökts i detta examensarbete var vilken mätosäkerhet kan uppnås med UAS vid framställandet av en DHM, vilken skillnad i lägesosäkerhet finns mellan studiens punktmoln jämfört med nationella höjdmodellen, samt mot punktmolnet genererat från traditionell flygfotografering och den ekonomiska aspekten vid användning av UAS. Detta utfördes genom att samla in data med hjälp av UAS över Furuvik, Gävle. Flyghöjden var 88 m över ett område på ca 1 ha. Därefter skapades en höjdmodell som kontrollerades enligt den tekniska specifikationen SIS-TS 21144:2013. I examensarbetet jämfördes punktmolnet som genererades från flygfoton tagna med UAS mot nationella höjdmodellen. Osäkerheten för den genererade höjdmodellen vid användandet av UAS visade ett bra resultat i höjd med en standardosäkerhet på 0,015 m. Punktmolnet genererat från Lantmäteriets bildmatchning låg 0,315-0,392 m under studiens punktmoln medan punktmolnet från laserskanningen låg 0,014-0,155 m över. Resultatet visade att användning av UAS är väldigt kostnadseffektivt när den nationella höjdmodellen över begränsade områden ska uppdateras. Det rekommenderas därför för Lantmäteriet att använda UAS för detta ändamål. Det blir mer än väl godkänt resultat och kostnaden är liten med tanke på resultatet, d.v.s. en metod för att verkligen kunna ajourhålla nationella höjdmodellen och komplettera traditionell flygfotografering över begränsade områden. Med denna metod slipper de vänta på att den traditionella flygfotograferingen ska ske. Tekniken går hela tiden framåt och inom en snar framtid kommer även laserskanning kunna ske med UAS. Det skulle vara intressant att se resultat av den metoden. Intressant skulle även vara att se om det i framtiden går att utesluta flygsignalering och verkligen kunna använda direkt georeferering för att spara tid ute i fält.<br>In this thesis we are going to investigate possibility of using UAS, over small areas, for updating national elevation model produced by the National Land Survey of Sweden. The subject of the thesis was proposed by the National Land Survey of Sweden. One of the main objectives of the study was to test if UAS can be used as a complement to traditional aerial photo. The use of UAS has increased over the years within for example geomatics, because it is a great tool when quick and effective results are required. The National Land Survey of Sweden uses airborne laser scanning to generate the national elevation model. The elevation model is then updated by traditional aerial photogrammetry. Other objectives that have been investigated in this study are what uncertainty can be expected with UAS when generating a DEM, the differences in uncertainty between the point cloud generated in this study to the national height model and to the point cloud generated from the traditional photogrammetry and the economic aspects when using UAS. For this purpose data was collected by UAS in Furuvik, Gävle. The flight height was 88 m over the area of about 1 ha. Then a DEM was created and controlled according to the technical specification SIS-TS 21144:2013. In this thesis a comparison between the point cloud generated in this study and the national elevation model has been performed. Uncertainty of the produced DEM using UAS showed very good result in height with a standard deviation of 0.015 m. The point cloud generated from the traditional photogrammetry was 0.315-0.392 m below the point cloud generated in this study, while the point cloud from laser scanning was 0.014-0.155 m above. The results showed that using UAS are very cost-effective to update the national elevation model. It is advisable for the National Land Survey of Sweden to update the national height model over small areas with this method. There will be more than efficient and the costs are small considering the result. In other word this method is to recommend when updating the national elevation model and can be used as a complement to traditional photogrammetry within limited areas. With this method, they will not have to wait for the traditional aerial photography to take place. The technology is constantly moving forward and in the near future laser scanning with UAS will occur. It would be interesting to see the results of that method. It would also be interesting to see if it is possible to exclude the ground control points, and really be able to use direct georeferencing to save time in the field.
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Zhu, Jiafeng. "Futures-Based Forecasts of U.S. Crop Prices." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/79490.
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Over the last decade, U.S. crop prices have become significantly more volatile. Volatile markets pose increased risks for the agricultural market participants and create a need for reliable price forecasts. Research discussed in this paper aims to find different approaches to forecast crop cash prices based on the prices of related futures contracts.
Corn, soybeans, soft red winter wheat, and cotton are the focus of this research. Since price data for these commodities is non-stationary, this paper used two approaches to solve this problem. The first approach is to forecast the difference in prices between current and future period and the second is to use the regimes. This paper considers the five-year moving average approach as the benchmark when comparing these approaches.
This research evaluated model performance using R-squared, mean errors, root mean squared errors, the modified Diebold-Mariano test, and the encompassing test. The results show that both the difference model and the regime model render better performance than the benchmark in most cases, but without a significant difference between each other. Based on these findings, the regime model was used to make forecasts of the cash prices of corn and soybeans, the difference model was used to make predictions for cotton, and the benchmark was used to forecast the SRW cash price.<br>Master of Science
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Svensson, Andreas, and Tim Zetterberg. "Utvärdering av höjdosäkerheten i digitala höjdmodeller framställda fotogrammetriskt med UAS." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-14822.
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Digitala ytmodeller (Digital Surface Model – DSM) används ofta i geodetiskt sammanhang. DSM har länge skapats bland annat med hjälp av fotogrammetri där flygbilder har tagits med traditionella flygningar. Intresset tilltar nu för att framställa DSM med hjälp av obemannade flygfarkoster, så kallade UAS (Unmanned Aircraft System). Den största fördelen med UAS är att det går snabbt och enkelt att få den lilla flygfarkosten upp i luften för att ta flygbilder och framställa DSM kostnadseffektivt.Syftet med detta examensarbete var att undersöka vilken höjdosäkerhet som kan uppnås i DSM som framställts genom fotogrammetri med UAS. För att åstadkomma detta har två flygningar gjorts den 25 april 2013 med en Gatewing X100 över ett område i Grillby där cirka 350 flygbilder togs sammanlagt. Efter flygningarna mättes med en totalstation 16 kontrollprofiler in på olika terrängtyper över flygområdet enligt rekommendationer i SIS-TS 21145:2007 ”Statistisk provning av digital terrängmodell”.Från de två flygningarna som gjordes i Grillby framställdes två olika DSM i programvaran AgiSoft Photoscan. DSM importerades därefter till SBG Geo där höjdskillnaderna mellan kontrollprofilerna och DSM beräknades. Medelavvikelsen i höjd varierade mellan -0,112 m och 0,050 m för de olika provytorna. De provytor som systematiskt avvek från DSM var asfaltprofilerna, dessa låg konstant (ca 0,1 m) under DSM. Anledningen tros ligga i bildmatchningen i programvaran AgiSoft Photoscan.De DSM som framställdes i detta examensarbete uppfyllde kraven för klass 4 enligt SIS-TS 21144:2007 vilket innebär att max medelavvikelse i höjd får vara 0,15 m. Det innebär, enligt samma SIS-TS, att framställda DSM är lämpade som projekteringsunderlag för arbetsplan väg och systemhandling järnväg (i jämn terräng).<br>Digital Surface Models (DSM) is common used for geodetic measurement today. Digital surface models have been created for a long time using photogrammetry where aerial photographs have been taken with traditional flights. The interest to produce DSM using unmanned air vehicles (UAS) has increased lately. The main advantage of a UAS system is that it is quick and easy to get the little aircraft up in the air to take aerial photographs and produce DSM cost-effective.The aim of this thesis was to investigate the height of uncertainty that can be achieved in DSM created by photogrammetry using UAS. To achieve this two flights have been made the 25th of April 2013 with a Gatewing X100. The flights were made over an area in Grillby where approximately 350 aerial photographs in total were taken. After the flights 16 control profiles were measured with a total station on different terrain types over the flight area as recommended by the document SIS-TS 21145:2007 “Statistical testing of Digital Terrain Models”.From the two flights that were made in Grillby, two different DSM was produced in the software AgiSoft Photoscan. The DSM was imported to SBG Geo and height differences between the control profiles and the DSM were calculated. This resulted in height differences which ranged between -0.112 m and 0,050 m in the various sample surfaces. The sample surface that deviated most from the DSM was the asphalt profiles that deviated about -0.1 m. It was considered to be a systematic error, but the source of the systematic error has not been located among the measurements. The error is believed to instead be in the image matching done by AgiSoft Photoscan. The DSM created in this thesis is classified as class 4 in a table from SIS-TS 21144:2007 which means that the max mean difference in height inside the DSM is ±0,15 m. This shows us that the DSM created with photogrammetry using UAS is suited for both as material for planning in railway and road constructions and for visualization of the ground.
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Arvidsson, Magnus, and Pettersson Tobias Loveere. "Utvärdering av mätosäkerhet i höjd för UAS med LiDAR." Thesis, Högskolan i Gävle, Samhällsbyggnad, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-33388.
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Digitala terrängmodeller (DTM:er) är ett vanligt förekommande verktyg i planering av olika samhällsutvecklande projekt inom stat, kommun och den privata sektorn. Inom planering för byggnationer av väg och järnväg används ofta SIS-TS 21144:2016 som ett dokument för styrning av produktionsprocessen vid framtagning av DTM:er, eller markmodeller. Med anledning av att ny teknik öppnar för möjligheter till snabbare, effektivare och klimatsmartare insamling av data, har denna studie till syfte att utvärdera Unmanned Aerial System (UAS) med Light Detection and Ranging (LiDAR) från YellowScan och dess mätosäkerhet i höjd. I denna undersökning jämförs resultatet från studien med klass 2 i SIS-TS 21144:2016 för flyghöjderna 50 m och 80 m samt för skanningsvinklarna 0 (lod), 10, 20 och 40 grader. Platsen för studien är belägen strax sydväst om Gävle i en nedlagd grustäkt med både hårt packat och något lösare underlag. Storleken för studieområdet begränsades till 200 x 300 m, vilket ger en 6 ha stor yta. Med utrustning för mätning med GNSS (Global Navigation Satellite System) mättes två stompunkter in med Nätverks-RTK (Real Time Kinematic). Därefter skapades ett stomnät med åtta punkter. Totalt mättes 26 kontrollytor in för jämförelser mot insamlade LiDAR-data. Datainsamlingen utfördes med obemannad flygfarkost (Unmanned Aerial Vehicle, UAV), GeoDrone X4L, utrustad med LiDAR-skannern YellowScan Surveyor meden integrerad IMU (Inertial Measurement Unit) från Applanix. Tillsammans bildade dessa enheter ett obemannat flygsystem (UAS) som kunde fjärrstyras och kommunicera sin position. All bearbetning utfördes i programvara från Terrasolid, baserat på data från flygrutten som först bearbetats i YellowScan CloudStation. Punkterna klassificerades för att urskilja marklassade punkter som användes vid generering av DTM:er. En justering av punktmolnet gjordes med avsikt att höja marklassade punkter för att motverka det brus som förekommer i data. Kontrollytorna kunde nu jämföras mot DTM:en och analyseras. Resultaten i studien visar att YellowScan Surveyor uppnår ett Root Mean Square (RMS) i höjd på 0,024 m vid 50 meters flyghöjd, vilket innebär 0,047 m utvidgad mätosäkerhet (2-sigma, 95 %). Även vid 80 meter uppnås relativt låg mätosäkerhet i höjd med ett RMS på 0,040 m. Resultaten i studien visar också att påverkan av mätning i en större skanningsvinkel inte är den enda faktor som försämrar resultatet.<br>Digital terrain models (DTMs) are a commonly used tool in planning various development projects within the state, municipalities, and the private sector. In planning for road and rail construction, the Swedish technical specification SIS-TS21144:2016 is often used as a document for controlling the production process of DTMs. Given that new technology opens the possibilities for faster, more efficient, and climate-smart data collection, this study aims to evaluate Unmanned Aerial System (UAS) with Light Detection and Ranging (LiDAR) from YellowScan and to evaluate the measurement uncertainty in height. In this study, the results of the study are compared with class 2 SIS-TS 21144:2016 for the flight heights 50 m and 80 m and the scanning angles 0 (in nadir), 10, 20 and 40 degrees. The site of the study is located just southwest of Gävle in a closed gravel pit with both hard packed and slightly looser substrates. The size of the study area was limited to 200 x 300 m, equivalent to 6 hectares. With Global Navigation Satellite System (GNSS) equipment, two control points were measured with Network-RTK (Real Time Kinematic). Subsequently, a control network of eight points was created. A total of 26 control grids were measured for comparisons of collected LiDAR data. The data collection was carried out with the Unmanned Aerial Vehicle (UAV) GeoDrone X4L equipped with LiDAR Scanner YellowScan Surveyor with an integrated Inertial Measurement Unit (IMU) from Applanix. Together, these units formed an UAS that could be remotely controlled and communicate its position. All processing was performed in software from Terrasolid, based on data from the flight route that was first processed in YellowScan CloudStation. The points were classified to distinguish ground points used in the generation of the DTM. An adjustment of the point cloud was made with the intention of raising ground level points to reduce the noise present in the data. The control grids could then be compared to the DTM and analysed. The results of the study show that YellowScan Surveyor achieves a Root Mean Square (RMS) in height of 0,024 m at 50 meters flight altitude, which equals 0,047m expanded measurement uncertainty (2 sigma level, 95 %). Even at 80 meters, relatively low uncertainty is achieved with an RMS of 0,040 m. The results of the study indicate that the influence of measurements at a wider scanning angle is not the only factor that deteriorates the results.
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Ghanim, Danny, and Max Holmström. "Utvärdering av reflektorlös vägmätning med totalstation, laserskanner och UAS." Thesis, Högskolan i Gävle, Samhällsbyggnad, GIS, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-25122.
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Denna studie undersöker reflektorlös mätning av vägmitt med totalstation samt skapande av markmodeller av vägar genom terrester laserskanning (TLS) och unmanned aerial system (UAS). Målet är att utvärdera metoder som undviker traditionell mätning på väg med handhållen prisma eftersom detta innebär att den som mäter måste befinna sig på vägen, vilket medför risker för trafikrelaterade olyckor samt kostnader för skyddsåtgärder. Studieområdet är en asfaltsbelagd parkeringsyta med vita markeringar liknande väglinjer. Genom TLS och fotogrammetrisk bearbetning av UAS-bilder skapades punktmoln och sedan markmodeller över en 60x10 m yta. Toleransen för markmodeller av asfaltsytor beskrivs i SIS-TS 21144:2016, som anger att den maximalt tillåtna medelavvikelsen i höjd är 0,02 m. Markmodellerna från både TLS och UAS-fotogrammetri uppfyllde kraven och erhöll medelavvikelser på -0,001 m respektive 0,005 m. Reflektorlös mätning som utförs från marknivå och ned mot terrängen med totalstation eller TLS resulterar i stora infallsvinklar, vilket i sin tur orsakar en förlängd träffbild. Pga. stråldivergens ökar dessutom träffbildens storlek med avstånd. En ytterligare faktor som påverkar reflektorlös mätning är mätobjektets reflektans. Asfalt har en reflektans på knappt 20 %, medan reflektansen hos de vitmålade markeringarna är tre gånger så hög. När det gäller TLS minskar dessutom punkttätheten, som påverkar vilka detaljer som kan identifieras, i samband med ökande avstånd. Toleranserna för inmätning av kontrollpunkter har i denna studie satts till 0,05 m i plan och 0,02 m i höjd. Resultaten visar att reflektorlös totalstationsmätning mot väglinjer uppnår RMS under toleransgränsen på upp till 55 m från instrumentet. I plan syns en trend som visar att avvikelserna ökar i samband med avstånd/infallsvinkel. I höjd syns inte en lika tydlig trend men vid ett avstånd på 57,5 m ökar avvikelserna drastiskt i både plan och höjd, vilket får betraktas som ett överskridande av den maximala räckvidden. Med dessa mätmetoder behöver hänsyn tas till bl.a. fri sikt, vägens utformning och skick, faktorer i omgivningen, trafikbelastning samt det rådande vädret. För både punktmoln och bilder behöver dessutom georeferering göras och lämplig upplösning bestämmas. Slutsatsen är dock att samtliga metoder kompletterar varandra och kan användas för insamling, kontroll, inpassning och komplettering av markmodeller och undviker samtidigt riskerna som medföljer handhållen prismamätning på väg.<br>This study evaluates the potential of reflectorless total station (TS) measurements when surveying road centerlines and the creation of digital terrain models (DTM) of road surfaces based on terrestrial laser scanning (TLS) and unmanned aerial system (UAS). The aim is to evaluate methods that avoid traditional surveying using a handheld prism since this means that the surveyor must be on the road, which creates risks of traffic related accidents as well as costs for protective measures. The study area is an asphalt-covered surface with white markings resembling roadlines. Through TLS and photogrammetric processing of UAS-images, pointclouds and subsequently DTM:s were created over a 60x10 m surface. The tolerance for DTM:s of asphalt-covered surfaces is specified in SIS-TS 21144:2016, which states a maximum average vertical deviation of 0,02 m. The DTM:s from the TLS and UAS-photogrammetry both fulfilled the requirements and obtained a quality of -0,001 m and 0,005 m respectively. Reflectorless measurements performed from ground level and down toward the terrain with TS or TLS result in large angles of inclination, which in turn causes an extended footprint of the laser beam. Because of beam divergence the footprint expands further with longer distances. Another factor that affects reflectorless measurements is the reflectance of the surface. Asphalt has a reflectance of barely 20 % while the reflectance of the white painted markings is three times as high. Additionaly when it comes to TLS, the point cloud density, which affects what details can be identified, diminishes with increasing distance. The tolerances for surveying of control points has in this study been set to 0,05 m horizontally and 0,02 m vertically. The results show that the reflectorless measurements of roadlines with TS achieves RMS below the tolerance limit up to 55 m from the instrument. The horizontal coordinates show a trend that the deviations increase with distance/angle of inclination. Vertically such a trend is not quite as clear, but at a distance of 57,5 m both the horizontal and vertical deviations increase drastically, which may be considered as exceeding the maximum range. With these methods adherences to some limitations need to be taken into consideration, such as line of sight, the road’s shape and condition, environmental factors, traffic and the weather. Furthermore, for both point clouds and images georeferencing needs to be done and a suitable resolution determined. The conclusion however, is that all methods complement each other and can be used for collecting, checking, fitting and completing DTM:s while avoiding the risks that traditional surveying methods using handheld prism creates.
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Persson, Magnus, and Tomas Gunnarsson. "Stödpunkters inverkan på osäkerheten vid georeferering av bilder tagna med UAS." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-14467.
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Unmanned Aerial Vehicles (UAVs) är obemannade flygfarkoster som främst använts och utvecklats inom det militära. Under senare år har användandet även tagit fart inom den civila sektorn, däribland mätningsbranschen. För att samla in geodata används Unmanned Aircraft Systems (UAS), vilka är system som består av fler komponenter än endast luftfarkosten t.ex. även kamera och kontrollstation. UAS är ett bra alternativ till traditionell flygfotografering då högupplösta bilder kan genereras till en låg kostnad. Eftersom UAS är en relativt ny metod måste osäkerheten utvärderas. Syftet med detta examensarbete är att utvärdera hur stödpunkter påverkar osäkerheten vid georeferering av UAS-bilder. Data erhölls från en flygning utförd av Sweco i november 2012. För att kunna utvärdera stödpunkternas inverkan översignalerades det 5 ha stora området med 35 stödpunkter. Nio olika konfigurationer av stödpunkter georefererades i programvaran Agisoft PhotoScan 0.9.0 och resultatet analyserades i Microsoft Excel, Geo Professional och Surfer 10L. Resultaten visar att osäkerheten för georefereringen minskar när antalet stödpunkter ökar, förutsatt att en jämn placering tillämpas. Bra georeferering uppnåddes när fyra stödpunkter användes. Vi rekommenderar ändå att minst fem stödpunkter används, fem stycken ger bra möjligheter till en god geometri – en i varje hörn och en i mitten. Det lägsta RMS-värdet i 3D (72 mm) erhölls med 17 stödpunkter jämnt fördelade över området. Det högsta RMS-värdet i 3D (190 mm) fick konfigurationen med sex stödpunkter placerade i ett av områdets hörn, något som tydligt visar hur stödpunkters placering (geometrin) påverkar osäkerheten av georefereringen. Även om fyra stödpunkter (en i varsitt hörn) bara får marginellt större RMS-värde än om en extra stödpunkt placeras i mitten, rekommenderas den sistnämnda för den bättre geometrin. För att kontrollera georefereringen rekommenderas några extra inmätta kontrollpunkter i området.<br>The main use and development of Unmanned Aerial Vehicles (UAVs) havethrough history been driven for military purposes, but in recent years the usehas increased also in the civilian sector, including the surveying industry. Inorder to collect geodata Unmanned Aircraft Systems (UAS) are used. UAS aresystems that consist not only of the unmanned vehicle, but also of componentslike a camera and a control station. UAS is a good alternative to traditionalaerial survey due to the high resolution images and the low operational cost.The uncertainty of UAS must be evaluated further since it is a relatively newsurveying method. The purpose of this study is to analyze the number of groundcontrol point’s (GCP’s) impact on the uncertainty of georeferencing UAS images.Data was collected from a flight conducted by Sweco in November 2012. The areawhich was flown (5 ha) was “over-signalized” by 35 GCPs in order to evaluate theirimpact on the georeferencing uncertainty. Nine different configurations of GCPswere georeferenced in the software Agisoft PhotoScan 0.9.0 and the result wasanalyzed in Microsoft Excel, Geo Professional and Surfer 10L. The result showsthat the uncertainty of the georeferencing decreases when the number of GCPsincreases, provided their distribution is even in the area. A goodgeoreferencing was obtained when four GCPs were used. Regardless, we recommendthe use of five, five provide a good geometry – one in each corner and one inthe middle. The least RMS value in 3D (72 mm) was found with 17 GCPs evenlydistributed in the area. The highest RMS value in 3D (190 mm) was found whenall six GCPs were placed in one of the corners of the area. This shows that thedistribution of GCPs has a great impact on the uncertainty of thegeoreferencing. Even if four GCPs (one in each corner) just get a little higherRMS value than if one extra GCP is placed in the middle, the latter isrecommended because of the favourable geometry. To be able to control thegeoreferencing it is recommended to survey some extra GCPs in the area.
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Blomberg, Andreas. "Utvärdering av mätosäkerheten vid georeferering med UAS och Post Processed Kinematic-GNSS." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-22145.
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UAS has been become a very popular tool in surveying and evaluation of the systems measurement uncertainties are necessary. The most common method for georeferencing UAS data is to use ground control points (GCP) in order to use them in block adjustment. In recent years’ new techniques for direct georeferencing with UAS have been presented, which in theory means that the position of the UAS can be determined accurately enough and therefore GCP’s can be excluded. This study evaluates uncertainties of the UAS Freya from SmartPlanes that don’t need GCP’s for georeferencing. The technique applied in the evaluation is based on Post Processed Kinematic (PPK) for coordinate determination of the UAS, which means that the collected GNSS data can be post processed using a reference station. The test area was a 280 x 320 m block in the north end of Gävle airport, Sweden. Each flight is conducted in two orthogonal blocks and evaluated in three different ways against the 16 GCP. The altitude was about 90 m for all flights. The uncertainty of the PPK-technique is tested and evaluated with three different methods to ensure both accuracy and potential use. In total five flights were assessed and evaluated with Agisoft PhotoScan against 16 GCP spread over the area. The position of each GCP’s was determined with four independent network RTK measurements. The results show that the georeferencing with the PPK-technique and block adjustment has potential to meet the uncertainties in level with indirect georeferencing using GCP. The results show very similar planimetric uncertainties, around 0,020 m in RMS, for all evaluations with the PPK-technique. The results of the uncertainty in height is more scattered where the two lowest results in a RMS under 0,015 m and the highest over 0,100 m for the difference against the 16 GCP. It is possible to achieve low uncertainties with the method without the use of GCP. For areas where establishment of GCP is not possible, using UAS equipped with PPKtechnology provides a very suitable alternative to use. The results show relatively large differences between the evaluations and in order to determine the exact cause of them, further studies are required.<br>Den starka teknikutvecklingen för UAS resulterar i flera nya produkter på marknaden och för att utvärdera deras mätosäkerheter krävs det kontroller av systemen. Den vanligaste metoden vid georeferering med UAS är att använda koordinatbestämda flygsignaler på marken. På senare år har metoder för direkt georeferering presenterats, vilket i teorin innebär att positionen för UAS kan bestämmas så pass noggrant att flygsignaler kan uteslutas. I denna studie utvärderas mätosäkerheter för Freya, ett UAS från SmartPlanes som med hjälp av bra positionering och blockutjämning ska kunna användas för georeferering utan flygsignalering. Systemet från Smartplanes bygger på Post Processed Kinematic (PPK) för koordinatbestämning, vilket innebär att insamlat GNSS data kan efterberäknas med korrektioner från en referensstation. Mätosäkerheten för PPK-tekniken testas och utvärderas med 3 olika metoder för att se både på mätosäkerhet samt möjlig användning. Totalt fem flygningar har utförts på ett testområde som var cirka 280x320 m och beläget i den norra delen av Gävle flygplats. Flyghöjden var kring 90 m för alla flygningar som vidare har bearbetats och utvärderats i programvaran PhotoScan från Agisoft. Kontrollen av mätosäkerheten har gjorts mot 16 spridda kontrollpunkter på marken som har positionsbestämts med fyra oberoende nätverks-RTK mätningar vardera. Varje flygning är utförd i två ortogonala block och utvärderades med fyra olika konfigurationer mot de 16 kontrollpunkterna. Resultaten visar att georeferering med hjälp av blockutjämning och PPK-tekniken har potential för att uppnå mätosäkerheter i nivå med indirekt georeferering med hjälp av stödpunkter på marken. I plan visar resultaten på väldigt jämna mätosäkerheter, kring 0,020 m i RMS, för alla utvärderingar med PPK-tekniken. Resultaten i höjd är mer spridda där de lägsta visar mätosäkerheter under 0,015 m RMS och de högsta över 0,100 m i RMS för avvikelsen mot kontrollpunkterna. Det är fullt möjligt att uppnå låga mätosäkerheter med metoden utan användning av stödpunkter. För användningsområden där stödpunkter inte kan etableras är detta UAS med PPK-tekniken ett mycket lämpligt alternativ att använda. Resultaten visar på relativt stora skillnader mellan de olika testade metoderna och för att avgöra den exakta orsaken till dem skulle vidare studier behövas.
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Hanson, Jeffrey Acton. "Seismic and hydroacoustic investigations near Ascension Island /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1998. http://wwwlib.umi.com/cr/ucsd/fullcit?p9823701.
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Hägglund, Sandra, and Rose-Marie Lindh. "Optimering av datainsamling med UAS : En studie i alternativa flyghöjder kontra mätosäkerheter utförd i Avesta." Thesis, Högskolan i Gävle, Samhällsbyggnad, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-30391.
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Studiens syfte var att genom UAS-fotogrammetri se om det var möjligt att uppnå en mätosäkerhet på 2–3 cm samt se om det är möjligt att använda sprayfärgade kryss som markstöd istället för masonitplattor med målade timglas och ändå uppnå samma mätosäkerhet. Detta gjordes från två olika flyghöjder, 80 m och 110 m för att få en till dimension på studien. Markstöden mättes in med GNSS och i studien användes UAS DJI Phantom 4 v2.0 vid flygfotograferingen. I plan kontrollerades kartan genom detaljmätning med hjälp av multistation etablerad med 180-sekunders metoden. Kontroll av kartan i höjd gjordes genom inmätning av kontrollprofiler med GNSS och multistation. Totalt bearbetades data från 4 inmätningar, data från 80 m där markstöd bestått av masonitplattor respektive sprayfärgade kryss och det samma från 110 m. Databearbetningen utfördes i Agisoft PhotoScan där bilderna bearbetades till en ortofotomosaik, DEM och DSM. Ortofotomosaiken och DEM importerades sedan till ArcMap för skapande av baskarta och för kontroll av koordinaterna i plan. Markmodellen importerades till SBG Geo för vidare bearbetning och kontroll av avvikelse mellan kontrollprofilerna och DEM. Resultatet av 42 st detaljmätningar gjordes genom beräkning av RMS-värdet mellan inmätta koordinater och motsvarande punkt i kartan. Vid flygfotografering från 80 m visade timglas ett RMS-värde på 0,038 m och kryss ett RMS-värde på 0,039 m. Motsvarande från 110 m visar att timglas gav ett RMS-värde på 0,062 m och kryss på 0,048 m. Alla inmätningar utom timglas från 110 m klarar toleransen mot HMK – Geodatakvalitet som är 5 cm och när enbart marknära objekt mättes gav det ett RMS-värde i plan på 0,026 m för timglas från 80 m och 0,023 m för kryss. 2–3 cm mätosäkerhet uppnåddes därmed. Från 110 m blev värdet 0,054 m med timglas och 0,035 m med kryss. Kontroll av höjdosäkerhet gjordes enligt SIS-TS 21144:2016, där 12 kontrollprofiler mättes in och jämfördes mot DEM. Resultatet från 80 m med timglas som markstöd visade en total medelavvikelse på 0,006 m med 0,019 m i standardosäkerhet. Från samma flyghöjd, men med inmätningar av kryss visade ett resultat om -0,001 m med standardosäkerhet 0,030 m. Från den högre flyghöjden med timglas genererades en total medelavvikelse på 0,010 m med standardosäkerhet 0,033 m. Motsvarande genererade kryss en total medelavvikelse på 0,026 m med standardosäkerhet 0,040. Alla 4 markmodellerna klarar den efterfrågade mätosäkerheten om 2–3 cm.<br>The aim of this study was to collect data through UAS photogrammetry and investigate if it was possible to achieve an uncertainty of 2-3 cm. The second aim was to investigate if it was possible to use spray-colored crosses as control points (GCP) instead of hourglass-painted fibreboards to achieve the same uncertainty. This was done from two different flight heights, 80 m and 110 m to add another dimension to the investigation. The GCPs were measured with GNSS and in the study a UAS DJI Phantom 4 v2.0 was used for aerial photography. The plane coordinates was checked by measuring details using multistation established with the 180-second method. Height control was done by measuring profiles with GNSS and multistation. All together data from 4 measurements were processed; from 80 m where GCPs consisted of hourglass and crosses, respectively, and the same from 110 m. The processing was performed in Agisoft PhotoScan where the images were aligned to an orthophoto mosaic. A DEM and DSM were also created. The orthophoto mosaic and DEM were used in ArcMap for digitizing a base map and for checking the plane coordinates. The DEM was imported to SBG Geo for further processing and control of deviation between profiles and DEM. The result of the 42 measured details was made by calculating the RMSE value between the measured plane coordinates and the corresponding points in the map. In aerial photography from 80 m, hourglass showed an RMSE value of 0.038 m and crosses an RMSE value of 0.039 m. Corresponding from 110 m, hourglass gave an RMSE value of 0.062 m and a cross of 0.048 m. All measurements except hourglass from 110 m can withstand the tolerance to HMK – Geodatakvalitet (2017) which is 5 cm. If only ground-level objects were to be measured the RMSE value of 0.026 m for hourglass from 80 m and 0.023 m for crosses reached the wanted measurement uncertainties of 2–3 cm. From 110 m the value was 0.054 m with hourglass and 0.035 m with cross. The control of the height uncertainty was made in accordance with SIS-TS 21144:2016, where 12 profiles were measured and compared with the DEM. The result from 80 m with hourglass showed a total mean deviation (MD) of 0.006 m with 0.019 m in standard deviation (SD). From the same flight height, but with crosses, a result of -0.001 m with SD showed 0.030 m. From the higher height with hourglass, a total MD of 0.010 m with SD 0.033 m was generated. The corresponding crosses got a MD of 0,026 m and a SD of 0,040 m. All 4 DEM can handle the required measurement uncertainty of 2-3 cm.
Books on the topic "MDD UCS"
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Nicolaus, Eric A. Rifle, U.S. CAL .30, M1D sniper's: Diagrams & pictures. Nicolaus Associates, 2005.
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Read, Robert R. Structured exit interviews using MDS. Naval Postgraduate School, 1985.
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Covert, Norman M. Cutting edge: A history of Fort Detrick, Maryland, 1943-1993. The Headquarters, 1993.
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Covert, Norman M. Cutting edge: A history of Fort Detrick, Maryland, 1943-1993. The Headquarters, 1993.
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United States. Office of Personnel Management. Office of Audits. Audit of the Federal Employees Health Benefits Program operations of M.D. Individual Practice Association, Inc. U.S. Office of Personnel Management, Office of the Inspector General, Office of Audits, 2010.
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Jay, Luvaas, Nelson Harold W, and Army War College (U.S.), eds. The U.S. Army War College guide to the Battle of Antietam: The Maryland Campaign of 1862. Perennial Library, 1988.
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Cole, Merle T. Solomons Mines: A history of the U.S. Naval Mine Warfare Test Station, Solomons, Maryland, 1942-1947. Calvert Marine Museum, 1987.
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Office, General Accounting. Mad cow disease: Improvements in the animal feed ban and other regulatory areas would strengthen U.S. prevention efforts : report to congressional requesters. GAO, 2002.
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Angleberger, Tom. Fake mustache: How Jodie O'Rodeo and her wonder horse (and some nerdy guy) saved the U.S. Presidential election from a mad genius criminal mastermind. Amulet Books, 2012.
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United States. Congress. Senate. Committee on Energy and Natural Resources. Subcommittee on Water and Power. Mid-Dakota Rural Water System Act of 1989 and Lake Andes-Wagner/Marty II units: Hearing before the Subcommittee on Water and Power of the Committee on Energy and Natural Resources, United States Senate, One Hundred First Congress, second session, on S. 1765 ... S. 2710 ... June 19, 1990. U.S. G.P.O., 1990.
Find full textBook chapters on the topic "MDD UCS"
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Oruabena, Bernard, and Okoh Elechi. "Expansive Soil Subgrade: Soil Treatment Using Waste Ceramic Dust and Cement." In Lecture Notes in Civil Engineering. Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-97-4355-1_63.
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AbstractThis study examines the potential application of leftover ceramic dust for stabilising expansive soil in infrastructure projects. We know that expansive soils have low strength and bearing capacity, which makes them troublesome in the natural world. Therefore, it’s crucial to level off weak or powerless soil to increase the sublevel’s bearing limit and support a suitable, long-lasting wearing course. To stabilise the soil, the poor soil was taken from Yenagoa, Bayelsa state in the South-South region of Nigeria, and mixed with varying amounts of waste ceramic dust. Standard Proctor compaction, soaked/unsoaked CBR testing, unconfined compressive strength tests, and consistency limit tests were used to evaluate the applicability of stabilised soil. The OMC appreciated at 7.5% of CD, which was utilized as an additive at 17.9 KN/m2, according to the results. From 1.72 to 1.74 KN/m2, MDD increased. From 9.3% at 0% to 16.77% (unsoaked) at 10% admixture (WCD + PLC) and 2.60% at 0%, according to the CBR test results, there was a rise. The highest (CBR) value was obtained when the mixture was soaked to 11.52%, as opposed to 16.77% when it was unsoaked. It was revealed that stabilisation in UCS improved with replacement ratios of 2.5%, 5%, 7.5%, and 10%, in that order. In conclusion, it was found that expanding soil stabilisation can be achieved without failure by using the ideal mix design.
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Lee, D. S., K. Srinivas, L. F. Gonzalez, and J. Periaux. "Uncertainty Based MDO of UAS Using HAPMOEA." In Computational Fluid Dynamics 2008. Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-01273-0_86.
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Boon, Maurits S., and Colin T. Huntley. "Special Circumstances." In Upper Airway Stimulation Therapy for Obstructive Sleep Apnea. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780197521625.003.0012.
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Upper airway stimulation (UAS) has emerged as a viable alternative to treat obstructive sleep apnea in select patients who cannot tolerate continuous positive airway pressure. This chapter discusses special populations and circumstances that may impact care of patients using UAS. Topics addressed include women receiving implants, patients with Down syndrome, left-sided implants, replacement of an internal pulse generator, revision surgery, use of UAS with other implanted medical devices, and implants outside of indications approved by the U.S. Food and Drug Administration. Evidence is provided where applicable, but for many of the situations detailed, limited published data are available; the information provided represents consensus and expert opinion.
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"Perfecting the UCAS form." In So you want to be a Doctor?, edited by David Metcalfe, Harveer Dev, and Michael Moazami. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780198836308.003.0009.
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The UCAS form comprises all of the details about an applicant that their considering medical schools get to see. It includes their demographics and academic information together with their school reference, but, most importantly, it includes their personal statement. The personal statement is essentially a letter from the applicant, about them, to the people deciding whether or not to interview them. This chapter discusses the ‘dos’ and ‘do-nots’ of writing a personal statement, providing the medical-school applicant with invaluable tips and tricks for ensuring theirs makes an impression. It highlights the essential things to include and the things that are best avoided.
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Zubenko, Georges. "Major Depressive Disorder In Alzheimer’s Disease." In Late-Life Depression. Oxford University PressNew York, NY, 2004. http://dx.doi.org/10.1093/oso/9780195152746.003.0029.
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Abstract Clinically significant depression is a common and important complication of Alzheimer’s disease (AD) that increases the suffering of patients and their families, produces excess disability, promotes institutionalization, and hastens death (Olin et al., 2002; U.S. DHHS, 1999). Estimates of the prevalence of depressive symptoms among patients with AD have been as high as 86% (Merriam et al., 1988). Most cross-sectional estimates of the coexistence of syndromal major depressive disorder (MDD) in elderly outpatients with probable AD range from about 15% to 25% (for reviews, see Mulsant and Zubenko, 1994; Olin et al., 2002; Teri and Reifler, 1987; Wragg and Jeste, 1989). The recurrent nature of this behavioral complication of AD suggests that an even larger proportion of patients eventually experience a major depressive episode (MDE) before death (Zubenko, 1992; Zubenko et al., 2003).
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"Statement of James M. Hughes, M.D." In Terrorism and Medical Responses: U.S. Lessons and Policy Iimplications. Brill | Nijhoff, 2001. http://dx.doi.org/10.1163/9789004479821_018.
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"Why U.S. Superiority Is Probably Inferior to MAD." In Analyzing Strategic Nuclear Policy. Princeton University Press, 2014. http://dx.doi.org/10.2307/j.ctt7zvvxj.8.
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Levy, Barry S. "Profile 5: Ira Helfand, M.D." In From Horror to Hope. Oxford University Press, 2022. http://dx.doi.org/10.1093/oso/9780197558645.003.0010.
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Each week for almost 40 years, Ira Helfand, an internist based in western Massachusetts, has worked treating patients with medical emergencies. And he has also spent much time helping to prevent the most terrifying global emergency: nuclear war. In 1977, Dr. Helfand was inspired by a book that raised his awareness about threats posed by nuclear power, and soon afterward he learned that nuclear weapons posed even greater threats. Along with physicians Helen Caldicott and Eric Chivian, he resurrected Physicians for Social Responsibility (PSR), which had been founded in the early 1960s by a number of physicians, including Victor Sidel, Jack Geiger, and Bernard Lown, who wrote seminal articles about the devastating effects that nuclear weapon attacks would have on U.S. cities....
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Frischer, Katya. "Insanity." In Landmark Cases in Forensic Psychiatry, edited by Merrill Rotter, Jeremy Colley, and Heather Ellis Cucolo. Oxford University Press, 2019. http://dx.doi.org/10.1093/med/9780190914424.003.0025.
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Chapter 25 relates to what is probably the most recognized, but perhaps the most rare, evaluation performed by a forensic professional. The pursuit of an insanity defense today is challenging and, in some states, not even permissible. These cases illustrate the evolution of the various state standards for establishing insanity (and therefore acquittal) for criminal defendants with mental illness. The following cases are included in this chapter: M’Naghten’s Case, Durham v. U.S., Washington v. U.S., Frendak v. U.S., Jones v. U.S., U.S. v. Torniero, Foucha v. Louisiana and Clark v. Arizona.
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Frischer, Katya. "Insanity." In Landmark Cases in Forensic Psychiatry. Oxford University Press, 2014. http://dx.doi.org/10.1093/med/9780199344659.003.0025.
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Chapter 25 relates to what is probably the most recognized, but perhaps the most rare, evaluation performed by a forensic professional. The pursuit of an insanity defense today is challenging and, in some states, not even permissible. These cases illustrate the evolution of the various state standards for establishing insanity (and therefore acquittal) for criminal defendants with mental illness. The following cases are included in this chapter: M’Naghten’s Case, Durham v. U.S., Washington v. U.S., Frendak v. U.S., Jones v. U.S., U.S. v. Torniero, Foucha v. Louisiana, and Clark v. Arizona.
Conference papers on the topic "MDD UCS"
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Fardink, Paul. "An Interview with Colonel Floyd Harold "Hal" Kushner, M.D., F.A.C.S U.S. ARMY Flight Surgeon and Vietnam Prisoner of War." In Vertical Flight Society 70th Annual Forum & Technology Display. The Vertical Flight Society, 2014. http://dx.doi.org/10.4050/f-0070-2014-9525.
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Crusan, Ambria, and Francine Overcash. "Improved Mediterranean diet pattern scores by increasing Omega-3 containing foods in U.S. adult diets." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/mnqj8831.
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Objective: The Mediterranean-Style Diet (MedD) pattern is associated with lower risk for chronic diseases. Key components to the MedD pattern are consumption of olive oil, green leafy vegetables, and fatty fish, all sources of omega-3 (O-3) fatty acids. The purpose of this study is to predict alignment to a MedD pattern using O-3 containing foods. Methods: A sample of 19,978 25-65 year olds with two reliable 24-hour recalls was obtained from the 2007-2018 National Health and Nutrition Examination Surveys. Multiple regression analyses determined differences by adherence level, high scorers (HS) vs. general population (GP), to the MedD pattern for dietary outcomes. Using isocaloric food substitution modeling within the GP, changes in MedD score were measured. Exclusive olive oil (OO) use was reported at 0.3% in GP; if OO use increased to half of oil as OO, MedD score would increase by 2.1 points. MedD score increased by 0.56 when replacing 4 oz. red meat for 4 oz. fish in the GP and 6.26 when replacing 0.67 cups starchy vegetables with 2 cups non-starchy vegetables. Conclusions: Increasing oil consumption to include half of oils from OO, replacing 4 oz of red meat with 4 oz of fatty fish, and replacing 0.67 cups starchy vegetables with 2 cups of non-starchy vegetables would help the GP to achieve better alignment to a MedD pattern.
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Ferry, Nicolas, Hui Song, Alessandro Rossini, Franck Chauvel, and Arnor Solberg. "CloudMF: Applying MDE to Tame the Complexity of Managing Multi-cloud Applications." In 2014 IEEE/ACM 7th International Conference on Utility and Cloud Computing (UCC). IEEE, 2014. http://dx.doi.org/10.1109/ucc.2014.36.
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Nikolinakou, M. A., P. B. Flemings, M. Heidari, X. Wang, and M. Johri. "Pressure and Stress Prediction Using Seismic Velocities, 3D Geomechanical Models and the Full Stress Tensor: Mad Dog Field, Deepwater GoM." In 58th U.S. Rock Mechanics/Geomechanics Symposium. ARMA, 2024. http://dx.doi.org/10.56952/arma-2024-0694.
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ABSTRACT: We discuss a 3D case study for pressure and stress prediction in the Mad Dog field, deepwater GoM. We employ a novel approach that couples seismic velocities with geomechanical models and the full stress tensor (including lateral and deviatoric stresses; FES workflow). We show that steeply inclined salt faces increase the stress ratio in wall rocks. We further show that below salt overhangs, the stress state remains practically uniaxial. We discuss that the approach predicts stress perturbations that result from the 3D salt geometry and extend km away from salt. We extract pressure and stress along a well and show that the geomechanical prediction of least principal stress is systematically lower than the uniaxial estimate but comparable to field measurements. This is because the 3D model captures the extensional effect of the anticline structure in the area. Overall, we demonstrate that the 3D FES models incorporate the complexity of salt loading not captured by any VES approach and can provide pressure and stress estimates along any existing or planned well paths. 1. INTRODUCTION Pre-drill pore pressure and stress prediction is crucial for borehole stability, planning of safe and economic well trajectories and design of casing plans (Dodson, 2004; Flemings, 2021; Zhang, 2013). It is also a key input in the exploration stage to determine the integrity of reservoir seals. Pressure-prediction workflows are commonly based on the vertical effective stress (Zhang, 2013). Such workflows have been successfully established because, in sedimentary basins, strain is uniaxial and sedimentation drives loading and overpressure generation (Bowers, 1995; Osborne & Swarbrick, 1997). In the vertical effective stress (VES) workflow, the vertical effective stress across the volume of interest in calculated by coupling the seismic velocity with a velocity – vertical effective stress relationship, for example that of Bowers (1995): (equation) where (equation) is the vertical effective stress, V is a velocity measurement (e.g., seismic or sonic), V0 the velocity of water, and A & B empirical coefficients calibrated using well measurements at a regional well (see Appendix A for nomenclature). Pore pressure, uVES, is then estimated as the difference between the vertical total stress (σv) and vertical effective stress: (equation) The vertical total stress is usually assumed to be equal to the overburden stress.
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Seipp, Trevor G., and Shiju V. P. George. "User’s Design Specification Recommendations for ASME Section VIII, Division 2." In ASME 2010 Pressure Vessels and Piping Division/K-PVP Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/pvp2010-26129.
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The UDS (Users Design Specification) is the design-basis document for ASME Section VIII, Division 2 pressure vessels. It defines the vessel design requirements and serves as the single point of reference for the Manufacturer’s Design Report (MDR). Despite its importance, the authors’ have observed instances where insufficient attention has been paid to the creation of this baseline document. This paper discusses both requirements and recommended good practices for writing a UDS in accordance with the new Division 2 requirements. The work and information flow to arrive at the required and recommended information is discussed. In particular, the multi-disciplinary nature of a well-developed UDS and the importance of change management will be emphasized. Finally, formatting and other good practices will be discussed.
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Haynes, Megan W., Andrey Gunawan, and Shannon K. Yee. "Techno-Economic Comparison Between Conventional and Innovative Combined Solar Thermal Power and Desalination Methods for Cogeneration." In ASME 2018 Power Conference collocated with the ASME 2018 12th International Conference on Energy Sustainability and the ASME 2018 Nuclear Forum. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/power2018-7515.
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The U.S. Department of Energy (DOE) has determined that solar power coupled desalination could be the next step in helping to resolve the water-energy nexus. For many decades, integration of concentrating solar power (CSP) electricity generation for combined power and water production has typically utilized the conventional method of steam Rankine cycles. Current research focuses on an enticing innovative method which combines CSP with Brayton cycles and uses supercritical CO2 (sCO2) as a working fluid, allowing for a broader temperature range. This techno-economic study analyzes the power and possible freshwater generation of each cycle and provides a comparison of the techno-economic advantages associated with each technology when applied to desalination processes. The results of this study suggest that recompression-closed Brayton (RCBR) cycle is likely to have the most significant impact in decreasing the levelized cost of electricity (LCOE), almost halving it from combining CSP with the traditional Rankine cycle. Also, to minimize levelized cost of water (LCOW) a smaller scale desalination facility which utilizes multi-effect distillation with thermal vapor compression (MED/TVC) instead of multi-stage flash distillation (MSF) is most applicable. Although the lowest LCOE values are for wet-cooled RCBR with MSF and MED/TVC, in areas where freshwater generation is crucial to be optimized there is only a 0.04 cents/kWh increase for dry-cooled RCBR with MED/TVC to a cost of 9.8 cents/kWh. This suggests the best candidate for optimizing freshwater generation while minimizing both LCOW and LCOE is dry-cooled RCBR with MED/TVC desalination.
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Xiao, Yuxing, Madhusuden Agrawal, Hans Vaziri, and Rosemary Anthony. "Sanding in Sliding-Sleeve Completed Wells in Moderately Competent Reservoir Formations – A Field Case." In 57th U.S. Rock Mechanics/Geomechanics Symposium. ARMA, 2023. http://dx.doi.org/10.56952/arma-2023-0158.
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ABSTRACT A sliding-sleeve sandface completion consists of a series of blank pipe segments, isolation packers, and short sleeves in-between serving as flow ports. That geometrical configuration renders a unique sanding mechanism. Due to a large opening in the annulus rock starts to disaggregate at a lower depletion than in a cased and perforated completion, but rock aggregates tend to be mainly in blocks and chunks, which are favorable in lowering sanding risk as bigger aggregates have a higher apparent strength and require a higher fluid velocity to mobilize and transport toward the flow ports. Also, fluid flow in the annulus accumulates from the packer and converges toward the sleeve. The annular fluid velocity thus is zero at the packer and the highest at the sleeve. Therefore, an effective practical measure to mitigate and lower sanding risk is to optimize the number and locations of packers and sleeves in relation to the reservoir formation strength and sandface flow contributions. The above sanding mechanism and practical ramifications are illustrated through historical sanding responses in 11 horizontal wells in an oil field in the UK North Sea. The reservoir formation is moderately competent and its UCS is 1000-3000 psi. The well flow rate ranges from a few thousand barrels per day (mbd) to 25mbd and most of wells have experienced watercut. Despite weak formation intervals that are expected to disaggregate from the get-go, high well rate and watercut, sanding to date is below the design tolerance. A method, including CFD modeling, was developed to estimate the annular fluid velocity and rock aggregate's pickup velocity – the minimum velocity required to mobilize rock aggregates. Through cross-referencing historical sanding responses empirical relationships between sand mass per meter length and annular fluid velocity were established for sand-prone formation intervals with and without watercut respectively. The method and empirical relationships can be used in optimizing sandface completion design in future wells and production and interventions in existing wells.
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Rahman, Abdul Samad Abdul, Norbaya Sidek, Sulaiman Hasim, Juhaizad Ahmad, Mohd Ikmal Mohd Fazlan, and Nur Syazwana Mohamad. "Coconut Shell Ash (CSA) as the Stabilizer for Soft Soil Treatment." In International Conference on Nanoscience and Nanotechnology 2022. Trans Tech Publications Ltd, 2023. http://dx.doi.org/10.4028/p-y966ph.
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Soft soil consists of inherent properties where it is unstable in geotechnical condition with low shear strength. The present of soft soil is one of the problematic ground conditions that can pose great challenges in the related field. Moreover, soft soil is not suitable for being used in the construction of highways and buildings due to its undesirable characteristics such as high-water content, low shear strength, low bearing capacity and low permeability. Thus, soil improvement will be crucial in future geotechnical practice for designing structures in weak soil. The aim of this study is to investigate the effectiveness of the use of coconut shell ash (CSA) as an additive material to improve the strength of the soft soil. Preliminary tests were carried out on the soft soil sample for identification and classification purposes. Then, engineering tests were carried out such as compaction tests to determine the optimum moisture content (OMC) and maximum dry density (MDD), Un-confined Compression Test (UCT) to assess the unconfined compressive strength of the soft soil when mixed with 0, 5, 10, and 15% of CSA. Finally, this study resume that the coconut shell ash can act as a stabilizer that will lower the cost of treatment and will benefit the environment.
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Dam, Tuan, Pascal Klink, Carlo D'Eramo, Jan Peters, and Joni Pajarinen. "Generalized Mean Estimation in Monte-Carlo Tree Search." In Twenty-Ninth International Joint Conference on Artificial Intelligence and Seventeenth Pacific Rim International Conference on Artificial Intelligence {IJCAI-PRICAI-20}. International Joint Conferences on Artificial Intelligence Organization, 2020. http://dx.doi.org/10.24963/ijcai.2020/332.
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We consider Monte-Carlo Tree Search (MCTS) applied to Markov Decision Processes (MDPs) and Partially Observable MDPs (POMDPs), and the well-known Upper Confidence bound for Trees (UCT) algorithm. In UCT, a tree with nodes (states) and edges (actions) is incrementally built by the expansion of nodes, and the values of nodes are updated through a backup strategy based on the average value of child nodes. However, it has been shown that with enough samples the maximum operator yields more accurate node value estimates than averaging. Instead of settling for one of these value estimates, we go a step further proposing a novel backup strategy which uses the power mean operator, which computes a value between the average and maximum value. We call our new approach Power-UCT, and argue how the use of the power mean operator helps to speed up the learning in MCTS. We theoretically analyze our method providing guarantees of convergence to the optimum. Finally, we empirically demonstrate the effectiveness of our method in well-known MDP and POMDP benchmarks, showing significant improvement in performance and convergence speed w.r.t. state of the art algorithms.
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Hamadas, Manel, Abdallah Sokhal, and Badreddine Bazine. "Formation Sampling Optimization Using Borehole Images and Acoustic Data in Tight Gas Sand Reservoir." In 57th U.S. Rock Mechanics/Geomechanics Symposium. ARMA, 2023. http://dx.doi.org/10.56952/arma-2023-0606.
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ABSTRACT In this paper, we present an integrated workflow designed to characterize the natural fracture systems and to optimize fluid sampling in a very complex and heterogeneous fractured tight sandstone reservoir. Conventional techniques are not suited for tight formations, and to overcome this challenge it is imperative to implement and enhance new technology. This advanced workflow aims to decrease uncertainties at different stages of the reservoir lifecycle through combined advanced tools. Electrical and Acoustic borehole images, Full Acoustic Waveform, and MDT Dual packer were incorporated in this study to optimize fluid sampling and increase the success rate of economic recovery. INTRODUCTION Almost all hydrocarbon reservoirs are affected in some way by natural fractures, but the effects of fractures are often poorly understood and largely underestimated. In tight reservoirs, natural fractures created through complex tectonic activity help create secondary porosity and promote communication between reservoir compartments (Irofti et al., 2022). However, these highly permeable channels sometimes short-circuit fluid flow in the reservoir, causing premature production of water or gas and rendering secondary recovery initiatives ineffective (Bratton et al., 2006).Since the introduction of the wireline formation testers in 1955, these tools have provided the oil and gas industry with measurements for the determination of formation pressure, fluids in-situ as well as giving formation fluid samples for identification and analysis. This conventional technique is well suited for thick and permeable clastic formations. Under low porosity and low permeability conditions, the wireline formations testers become unsuitable as they may not be able to isolate the zone, may miss a thin zone or in a formation with very low permeability, the contact area with the packer may be too small to let the fluid flow. When testing is to be conducted out employing pricey rig operations, evaluation of heterogeneous reservoirs using open hole logs and cores carries some risk (Aoun, Soto, et al., 2022; Ifrene et al., 2023) The modest success rate of sampling operations, fluid sampling presents a challenge in tight reservoirs, therefore it is imperative to adopt innovative techniques. To overcome this challenge, we proposed in this article a workflow to increase and optimize the success rate. This includes the combination of borehole image logs and acoustic waveforms, two technologies aiming to enhance formation sampling and recovery rate.
Reports on the topic "MDD UCS"
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Johnsen, Linda, and John David Didriksen. Rapport: Åpen forskning på UiS. University in Stavanger, 2019. https://doi.org/10.31265/usps.304.
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I 2017 fastsatte Regjeringen nasjonale retningslinjer for åpen tilgang. Alle vitenskapelige artikler som er offentlig finansierte skal som hovedregel gjøres åpent tilgjengelige. Internasjonalt, spesielt i EU, har det også lenge vært et stort fokus på åpen forskning. Norges Forskningsråd (NFR) fastsatte i 2017 en politikk for åpne forskningsdata. Dette danner bakgrunnen for at Universitetsdirektøren har nedsatt en arbeidsgruppe som skal utrede en politikk for åpen forskning ved UiS. NFR legger opp en forskningspolitikk som fokuserer på at forskningsresultater skal komme samfunnet til gode. For å oppnå dette må forskningsproduksjonen være åpent tilgjengelig. Plan S er et europeisk initiativ lansert i 2018 for å sikre en rask overgang til åpen tilgang for all offentlig finansiert forskning. Hovedprinsippet er at alle vitenskapelige publikasjoner som støttes av offentlige midler skal utgis åpent, uten embargo. NFR har sluttet seg til, og vil la kravene gjelde fra og med 2021. I praksis betyr dette at de vil gjelde for artikler som sendes inn for publisering fra 2022. DORA-deklarasjonen er et sett med anbefalinger vedrørende evaluering av forskning. Hensikten er å komme frem til egnede metoder, uten å lene seg for mye på bibliometriske faktorer. Forskningens egenverdi skal evalueres, og man skal unngå å legge overdreven vekt på publisering i de mest prestisjetunge tidsskriftene. Open Journal Systems (OJS) og Open Monograph Press (OMP) er åpne publiseringsplattformer på UiS, for henholdsvis tidsskrifter og bøker. Biblioteket har ansvaret for driften av dem. OJS stiller samme krav til kvalitet, fagfellevurdering og redaksjonsarbeid som andre forlag. OMP har ikke krav til fagfellevurdering, og er derfor ikke poenggivende. Gjennom Direktoratet for IKT og fellestjenester i høyere utdanning og forskning (Unit) har UiS inngått avtaler med Wiley og Elsevier, der det ikke lenger er nødvendig å betale publiseringsgebyr (på engelsk: «article processing charge», APC) for å publisere åpent i deres tidsskrifter. Fra 2020 vil konsortiet også ha avtaler med Springer, samt Taylor & Francis. EU, NFR og andre forskningsfinansiører krever at forskningsdata skal være åpent tilgjengelige så sant det er mulig. Både NFR og Europakommisjonen følger «åpen som standard»-prinsippet når det gjelder tilgang til forskningsdata: «Så åpne som mulig, så lukkede som nødvendig». Forskningsdata fra UiS skal behandles på en måte som samsvarer med de internasjonalt anerkjente FAIR- prinsippene. UiS har signert avtale med UiO for lagring av sensitive data. Tjeneste for Sensitive Data (TSD) er et fullt sett med tjenester, fra innsamling av data, til analyse, behandling og lagring, i sikrede omgivelser. En datahåndteringsplan er et dokument som beskriver hvordan data fra et prosjekt skal håndteres gjennom hele prosjektets livssyklus. NFR krever datahåndteringsplan for prosjekter de støtter, med mindre man kan gi gode grunner for at det ikke er nødvendig. Arbeidsgruppen anbefaler bruk av Norsk senter for forskningsdata (NSD) sin datahåndteringsplan. Arbeidsgruppen anbefaler fem tiltak som vi mener er hensiktsmessige for å få en mer åpen forskning ved UiS, se siste avsnitt i rapporten.
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Pekour, Mikhail, and Matt Newburn. Aerosol Inlets for a Mid-Sized Uncrewed Aerial System (UAS). Office of Scientific and Technical Information (OSTI), 2022. http://dx.doi.org/10.2172/1863934.
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Pekour, Mikhail, and Matthew Newburn. Aerosol Inlets for a Mid-Sized Uncrewed Aerial System (UAS). Office of Scientific and Technical Information (OSTI), 2022. https://doi.org/10.2172/2569529.
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Hansen, Edward. Mid-rotation yields of biomass plantations in the north central U.S. U.S. Department of Agriculture, Forest Service, North Central Research Station, 1992. http://dx.doi.org/10.2737/nc-rp-309.
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Gupta, Neeraj. Mid-Atlantic U.S. Offshore Carbon Storage Resource Assessment Project: Final Technical Report. Office of Scientific and Technical Information (OSTI), 2019. http://dx.doi.org/10.2172/1566748.
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Binette, Joanne. Urban vs. Rural Living in the U.S. Pre- and Mid-COVID-19. AARP Research, 2021. http://dx.doi.org/10.26419/res.00414.009.
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Zwetsloot, Remco, Jack Corrigan, Emily Weinstein, Dahlia Peterson, Diana Gehlhaus, and Ryan Fedasiuk. China is Fast Outpacing U.S. STEM PhD Growth. Center for Security and Emerging Technology, 2021. http://dx.doi.org/10.51593/20210018.
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Since the mid-2000s, China has consistently graduated more STEM PhDs than the United States, a key indicator of a country’s future competitiveness in STEM fields. This paper explores the data on STEM PhD graduation rates and projects their growth over the next five years, during which the gap between China and the United States is expected to increase significantly.
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Grönbäck, Anna-Maria, Tobias Andersson Granberg, and Niki Matinrad. Tillämpningar av modern teknik inom räddning : möjligheter och framtida frågeställningar. Linköping University Electronic Press, 2024. http://dx.doi.org/10.3384/9789180758468.
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Denna rapport ger en översikt över forskning och erfarenheter gällande räddningsinsatser där nya tekniker har använts, eller skulle kunna användas, vid såväl faktiska insatser som vid övning. Via en litteraturstudie, kompletterad med intervjuer med personer som är verksamma i projekt inom området, identifierades utmaningar och potential med modern teknik inom räddning. De olika teknologierna kategoriserades som Unmanned aerial/ground/surface vehicles (UXV), Artificiell intelligens (AI), Extended reality (XR, vilket inkluderar bland annat virtual och augmented reality), Kommunikationer, Sensorer, Robotar och Övrigt.Inom området artificiell intelligens för räddning behövs projekt som kan ta fram data av god kvalitet för att träna AI-modeller inom olika räddningstillämpningar (till exempel identifiering av skogsbrand, eller eftersök av person) i Sveriges varierande miljöer. Dessutom måste data och modeller valideras tillsammans med praktiker och förankras i räddningsverksamheten. Genom att utbilda responspersonal i principerna för maskininlärning kan användbarheten öka och risken för felaktiga resultat och tolkningar minskas.Teknikutvecklingen går fort medan relaterad metodutveckling och utvärdering ligger efter. För effektiv implementering av ny teknik är det viktigt att, tillsammans med användarna, undersöka vilka behov räddningstjänsten har och att ta fram metoder och modeller för hur nyttan med den nya tekniken ska utvärderas. Vidare måste den nya tekniken integreras med nuvarande arbetsmetoder, och modeller och metoder för effektiv gemensam resursanvändning av såväl nya som befintliga resurser måste utvecklas. Många mindre organisationer har svårt att själva driva denna typ av större utvecklingsprojekt, men skulle kunna hjälpas av administrativt stöd, till exempel från Myndigheten för samhällsskydd och beredskap (MSB).Säkra, robusta kommunikationsmöjligheter vid räddningsinsatser är ett viktigt område, och vidare forskning behövs för att möjliggöra detta med hjälp av drönare (UAS) i såväl fjällmiljö som till havs. Dessutom behövs flera projekt som kan tillhandahålla säkra lösningar för kommunikation och datasäkerhet inom räddning, och forskning kring hur relevant informationsdelning mellan olika aktörer kan möjliggöras. Användandet av UAS inom räddning börjar bli etablerat, och det finns potential i att utforska möjligheten med delat användande, till exempel hur drönare med andra tillämpningsområden (exempelvis matleveranser) skulle kunna bidra i räddningsinsatser. Många av de undersökta teknologierna kan användas kombinerat, till exempel kan en AI-modell tolka bilder som fångas av en drönare. Hur olika teknologier kan kombineras är ett område med fortsatt stor potential. Det saknas också vetenskapliga studier över potentialen av användningen av exoskelett inom räddning.
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Binette, Joanne, and Stephanie Firestone. Living in a Multigenerational Household Pre-COVID / Mid-COVID Among Hispanics in the U.S. Infographic. AARP Research, 2021. http://dx.doi.org/10.26419/res.00414.007.
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Tengesdal, Morten. Frå transistor til datamaskin. University of Stavanger, 2018. http://dx.doi.org/10.31265/usps.196.
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Dette skrivet prøver å gi ei forståing av korleis datamaskinar er oppbygde og virkar. Ein ser også på korleis ein kan programmera mindre datamaskinar brukte til styring og overvaking av prosessar. Skrivet er laga for bruk i emnet Datamaskinarkitektur ved Universitetet i Stavanger (UiS). Det kan også brukast til å gi ei innføring i digitalteknikk generelt og som ein del av dette, mikroprosessoren sin struktur og virkemåte. Ein får også ei innføring i grunnlaget for konstruksjon av datamaskinar. Ein har prøvd å gjera framstillinga kort og klar. Hovudfokus er på dei ulike byggjesteinane i ein datamaskin og korleis digitalteknikk blir praktisert i dag. Mykje av den klassiske digitalteknikken som manuell logikkonstruksjon med enkle portar av ein type, manuell optimalisering av logikk vhja. Karnaugh-diagram og konstruksjon av tilstandsmaskinar basert på J-K-vipper er tillagt redusert vekt samanlikna med vanlege lærebøker. Utviklingsprosjekt i dag tar stort sett utgangspunkt i programmerbar elektronikk. Mange klassiske metodar er her innbakt i utviklingsverktøyet ein bruker, eller blir realisert på andre måtar. Tema som logikkoptimalisering er likevel tatt med til ein viss grad der dette høyrer heime. Emnet Datamaskinarkitektur kom inn som ein obligatorisk del av bachelorstudia i data og elektro ved UiS hausten 2013. Læringsmåla for desse bachelorstudia kan formulerast som vist i det følgjande. Studentane skal som ferdige ingeniørar i data vera i stand til å: - Forstå ulike typar operativsystem. - Spesifisera, utvikla og testa objektorienterte datasystem. - Utnytta kjente algoritmer og datastrukturar til å løysa konkrete datatekniske problem. - Utvikla og bruka databaser. - Planleggja og driva datasystem. - Vurdera og utvikla nettbaserte dataløysinger. Studentane skal som ferdige ingeniører i elektro vera i stand til å: - Analysera og konstruera mikroprosessorbaserte system og programvare for desse. - Vurdera måletekniske løysingar for ei gitt oppgåve. - Vurdera komponentar og metodar for overvaking og automatisering av prosessar og produksjonslinjer. - Konstruera og programmera PLS- baserte styringssystem. - Utvikla diskrete algoritmer for regulerings- og signalbehandlingsformål. Ei solid forståing av korleis ein datamaskin er oppbygd og virkar er eit grunnleggjande vilkår for dei fleste av desse måla. Skrivet blir som vist gjort tilgjengeleg under ein såkalla Creative Common-lisens. Dette gir brei tilgang og gjer det i tillegg mogleg å byggja på eit stort tilfang av materiell som er gjort tilgjengeleg under same lisens, f.eks. frå den store dugnadsbasen Wikimedia. I tillegg er det i skrivet brei bruk av referansar til utdjupande stoff på internett. Ein del av stoffet på mikroprosessorar og datamaskinkonstruksjon er basert på skrivet som blei laga for eit tidlegare datamaskinemne ved UiS. I tillegg er vedlegg A.1 basert på forelesingsnotat i digitalteknikk frå 2009 av Trygve Eftestøl, UiS. Desse notata innheldt også handteikna skisser av Tom Ryen, UiS. Elles har Jon Fidjeland, UiS, kome med mange verdifulle kommentarar undervegs i arbeidet. Sidan oppstarten i 2013 har rundt 400 studentar tatt emnet Datamaskinarkitektur, og spørsmåla og kommentarane frå dei har påverka utviklinga av skrivet gjennom desse åra. Skrivet er norsk. Engelske omgrep blir sett i hermeteikn viss dei blir nytta åleine og i parentes når dei blir viste saman med norsk utgåve av nemninga.