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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Inventory management model based on a stock control system and a kraljic matrix to reduce raw materials inventory

Chancasanampa-Mandujano, Jesenia, Espinoza-Poblete, Karla, Sotelo-Raffo, Juan, Alvarez, Jose Maria, Raymundo-Ibañez, Carlos 27 September 2019 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / This research project proposes a supply management model in a consumer goods company in Lima, Peru, to improve stock control and avoid raw materials stockouts and overstock. A Kraljic matrix was used to identify products based on their criticality considering material segmentation, warehouse capacity and times, and ABC segmentation to classify products on each quadrant of the matrix. This project also focuses on defining purchasing and supply strategies in each quadrant of the matrix. This model involves the development of three processes that are related to a new purchasing strategy: economic order quantity, lot-for-lot ordering, and just in time. This new system is based on a more accurate inventory because continuous improvement attracts employees’ attention and engages them in reducing the number of manual notifications made by operators every month. Moreover, after implementing the new procedure for recording inventories, the inventory record was 87% accurate, whereas, in the past, the inventory was not counted and was performed by employees of other areas.
62

The Evaluation of Adsorbents for the Removal of Aflatoxin M1 from Contaminated Milk

Womack, Erika D 11 December 2015 (has links)
Taking precautions to restrain aflatoxin M1 (AFM1) from milk is critical, particularly due to the health and economic impact AFM1 imposes. The predominant post-harvest means of reducing AFM1 in milk includes the addition of sequestering agents to feed to diminish the bioavailability of aflatoxin B1 (AFB1), the parent compound of AFM1 found in contaminated feed. Still, residual AFM1 has been found in the milk. Using sequestering agents added to raw milk, we found that activated carbon was the most effective binder to reduce AFM1 contamination. The combination of 0.75% granular activated carbon (GAC) and a flow rate of 0.4 mL/min to pump contaminated milk through a glass column were chosen as optimum conditions for the removal of AFM1. These conditions obtained a 98.4% reduction of 0.75 ng/mL AFM1 from raw milk. The treated milk was also analyzed to assess the effects of GAC on milk constituents. The results determined that GAC had no significant effect on major nutritive milk constituents: total protein, lactose, minerals, and fat. Additionally, we optimized an extraction method coupled to high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) that minimized matrix effects, lowered the levels of detection, and reduced analysis costs. The optimized extraction method was based on QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe). Results determined 5 mL milk (15°C) with 10 mL acetonitrile, 3200 g centrifugation, and 0.2 μm syringe filter were the optimum conditions for the extraction of 0.5 ng/mL AFM1 from raw milk. The method was validated according to AOAC guidelines. This study reports experimental results on AFM1 remediation from raw bovine milk. The use of GAC for the removal of AFM1 in raw milk has reduced the amount of AFM1 below the FDA action limit and European Union maximum regulatory level. This method could have a global health impact, particularly, for people in developing nations and for infants and children who are more susceptible to the adverse effects of AFM1.
63

Heat Treatment of Lithic Raw Materials: Archaeological Detection and Technological Interpretation

Trubitt, Mary Beth D. January 1981 (has links)
No description available.
64

A preliminary investigation of the correlation between IQ scores and modality

McKay, Nancy Spitler January 1980 (has links)
No description available.
65

Uncertainty comparison of Digital Elevation Models derived from different image file formats

Spring, Ted January 2014 (has links)
Unmanned Aerial Systems (UAS) have become increasingly popular recently for surveying and mapping because of their efficiency in acquiring remotely sensed data in a short amount of time and the low cost associated with them. They are used to generate digital elevation models (DEM) derived from aerial photography for various purposes such as the documentation of cultural heritage sites, archaeological surveying or earthwork volume calculations. This thesis investigates the possible effects different file formats may have on the quality of elevation models. In this thesis, an UAS survey was simulated using a digital camera to produce six DEMs based on JPEG, TIFF and RAW format in Agisoft Photoscan by taking two sets of images of a city model, in different light conditions. Furthermore, a reference DEM was produced in Geomagic Studio using data from a Leica Nova MS50 Multistation. The DEMs were then compared in Geomagic Control. The results from the 3D comparison in Geomagic Control show that the standard deviation of all elevation models is 4 mm with the exception of the elevation model derived from raw-edited images taken with lighting, which has a standard deviation of nearly 6 mm. Also, all of the models have an average deviation of 0.4 mm or less. The significant deviations in all DEMs occur in areas where the multistation lacked vision of certain objects of the city model such as walls, or on the edges of the analysed area. Additionally, the georeferencing results from Photoscan show that the DEMs based on normal light condition images have slightly lower georeferencing errors than the DEMs with lighting. It has been concluded that it is difficult to say whether file formats have any noticeably effect on the uncertainty of digital elevation models.
66

Sourcing Oldowan and Acheulean Stone Tools at Oldupai Gorge (Tanzania)

Favreau, Julien January 2024 (has links)
Hominins habitually moved across landscapes to forage for resources, which can be investigated by the probabilistic attribution of stone tools to raw material sources. The sources that were available to Pleistocene hominins at the UNESCO World Heritage Site of Oldupai Gorge (Tanzania) have been studied for over a half-century. However, limited reference collections have prevented detailed investigations on the degree to which hominins transported stone tools. The primary goal of this dissertation was to identify the locations and distances over which Oldowan and Acheulean hominins transported raw materials at Oldupai Gorge and interpret the results in the context of the human evolutionary record. Fieldwork consisted of sampling metamorphic and volcanic outcrops to supplement an existing reference collection. An equally important fieldwork component consisted of conducting excavations at four occupation sites, including, from oldest to youngest, Ewass Oldupa (Oldowan), Elang’ata Oljurusi (Acheulean), Engaji Nanyori (Acheulean), and Emurutoto (Acheulean). Laboratory work consisted of studying artefact collections to obtain general information about toolmaking practices, and characterising geological samples and stone tools at the macroscopic and geochemical levels for comparative analyses using computational statistics. The overarching aim of this dissertation was to investigate whether the shift from Oldowan to Acheulean toolmaking was accompanied by equally more complex landuse strategies amidst progressive aridification. Informed by probabilistic sourcing results, the evidence presented herein indicates that the Oldowan to Acheulean transition in the Oldupai basin was accompanied by more focalised landuse. Yet, both Oldowan and Acheulean hominins altered their mobility to variable environments ranging from woodlands to steppe deserts. These behavioural responses represent possible explanations for the adaptive radiation of hominin populations across, and out of, Eastern Africa during the Early and Middle Pleistocene. / Dissertation / Doctor of Philosophy (PhD) / Hominins habitually moved across landscapes to forage for resources, which can be investigated by sourcing the raw materials that were fashioned into stone tools. The raw material sources at the UNESCO World Heritage Site of Oldupai Gorge (Tanzania) have been studied for over a half-century. However, limited reference collections have prevented thorough investigations on the degree to which hominins transported tools during the Pleistocene. Informed by the systematic sampling of metamorphic and volcanic outcrops, macroscopic and geochemical data were used to source Oldowan and Acheulean artefacts excavated from four occupation sites across the Oldupai Gorge study area. The evidence presented herein indicates that the shift from Oldowan to Acheulean toolmaking was accompanied by more focalised landuse amidst growing aridity. Yet, both Oldowan and Acheulean hominins altered their mobility to variable environments. This represents a plausible explanation for the adaptive radiation of hominin populations into increasingly diverse biogeographic zones through time.
67

Visualising animal hard tissues

O'Connor, Sonia A., Sparrow, Thomas, Holland, Andrew D., Kershaw, Rachael, Brown, Emma, Janaway, Robert C., Ugail, Hassan, Wilson, Andrew S. 19 August 2022 (has links)
No / This chapter summarises AHRC/EPSRC Science and Heritage Programme-funded research to develop a digital resource to disseminate knowledge of the identification of osseous and keratinous animal hard tissues. The choice of materials in the manufacture of individual artefacts or classes of objects can make a major contribution to understanding their cultural significance and questions of provenance or authenticity. This resource builds on understanding gained through a Fellowship to O’Connor in developing, evaluating and validating identification criteria for these materials in raw, worked and decayed states. The resource concentrates on the non-destructive visual methods of particular relevance to the examination of artworks, historic and archaeological artefacts. The chapter highlights the potential of various visualisation methods and digital technologies to capture and combine 2D images and 3D models and guide the viewer through the multi-scalar visual cues of each material to a reliable identification. By accessing a range of collections, the project has produced a comprehensive and accessible resource, disseminating these findings more widely than could be achieved by a physical reference collection. This resource supports the identification of cultural heritage objects for conservation scientists and heritage professionals and informs the fight against the illegal hunting and trafficking of rare and endangered species. / VAHT was funded through an AHRC-EPSRC Science and Heritage Programme Research Development Award (AH/K006169/1) that developed directly from Sonia O'Connor's AHRC/EPSRC Science & Heritage Programme Fellowship (AH/H032150/1)—Cultural Materials Worked in Skeletal Hard Tissues (COWISHT).
68

Colecalciferol regula os parâmetros hematológicos e a produção de citocinas pró-inflamatórias renais em camundongos diabéticos e nas células RAW 264.7 / Colecalciferol regulates haematological parameters and the production of renal proinflammatory cytokines in diabetic mice and RAW 264.7 cells

Bella, Leonardo Mendes 07 December 2018 (has links)
Os efeitos causados pelo tratamento em conjunto da insulina e do colecalciferol em indivíduos diabéticos não estão completamente elucidados. O presente trabalho avaliou o efeito de ambos os hormônios nos rins, no fígado, no coração e nos parâmetros hematológicos de camundongos machos (C57BL/6) sadios e diabéticos, bem como a ação do colecalciferol (in vitro) na resposta imunológica desenvolvida pelas células RAW 264.7 e pelos macrófagos peritoneais (MP) após estímulo com lipopolissacarídeo (LPS). Após dez dias da administração da aloxana (60 mg/kg), animais diabéticos exibiram redução do ganho de peso corporal e hiperglicemia quando comparados aos animais que receberam salina. No sétimo dia do período experimental, foi verificado que animais diabéticos que não receberam nenhum hormônio, em relação aos não diabéticos, exibiram redução do peso corporal, dos níveis de hemoglobina (Hb), hematócrito, hematimetria, insulina, TNF-α e IL-6 (coração) e aumento da glicemia, da relação peso corpóreo/peso rim esquerdo, das concentrações séricas de ureia, creatinina, Fosfatase Alcalina (FAL), Lactato desidrogenase (LDH) e lactato, fator de necrose tumoral (TNF)-α, interleucina (IL)-6 e IL-10 (no rim); o tratamento com insulina (1 UI/300 mg/dL glicemia), em relação aos animais diabéticos não tratados, promoveu aumento do peso corporal, das concentrações séricas de insulina e redução da glicemia, das concentrações séricas de ureia e da razão TNF-α/IL-10 (coração); o tratamento com colecalciferol (800 UI/dia), em relação aos animais diabéticos não tratados, promoveu aumento das concentrações séricas de 25-hidroxicolecalciferol [25(OH)D], Hb, hematócrito, hematimetria, IL-10 (coração) e reduziu IL-6, IL-10, TNF-α e EPO (rim); os animais diabéticos tratados com insulina, em relação aos animais diabéticos suplementados com colecalciferol apresentaram aumento do peso corpóreo, de ureia sérica, IL-6 e TNF-α (coração) e redução da glicemia, das concentrações séricas de lactato, de IL-6, TNF-α, IL-10 e EPO (rim); os animais -que receberam ambos os hormônios, em relação aos animais tratados com insulina, apresentaram aumento sérico de insulina e lactato; os animais diabéticos que receberam ambos os hormônios, em relação aos animais diabéticos tratados com colecalciferol, exibiram aumento sérico de 25(OH)D, de insulina, além da redução das concentrações de IL-10, da razão de TNF-α/IL-10 e TNF-α/IL-6 (coração); animais diabéticos que receberam ambos os hormônios, em relação aos diabéticos não suplementados com colecalciferol, exibiram: aumento de insulina sérica e redução das concentrações séricas de ureia e das razões renal e hepática de TNF-α/IL-6; células RAW 264.7 estimuladas pelo LPS e tratadas com 100 nM colecalciferol exibiram maior expressão da CYP27B1 e redução na liberação de mediadores inflamatórios quando comparadas ao grupo estimulado pelo LPS. Entretanto, não foi observado o mesmo efeito nos MP. Em conjunto, os resultados sugerem que: 1) em animais diabéticos, o colecalciferol pode modular parâmetros hematológicos e que a insulina pode melhorar a função renal, bem como a recuperação do peso corporal; 2) o colecalciferol pode ser metabolizado pelas células RAW 264.7 e modular a resposta imunológica desencadeada pelo LPS. / The effects caused by the treatment of insulin and cholecalciferol in diabetic subjects are not completely elucidated. The present study evaluated the effect of both hormones on the kidneys, liver, heart and hematological parameters of healthy and diabetic male mice (C57BL/6), as well as the action of cholecalciferol (in vitro) on the immune response developed by the cells RAW 264.7 and peritoneal macrophages (MP) after stimulation with lipopolysaccharide (LPS). After ten days of alloxan administration (60 mg/kg), diabetic animals exhibited a reduction in body weight gain and hyperglycemia when compared to animals that received saline. On the seventh day of the experimental period, it was verified that diabetic animals that did not receive any hormones, in relation to non-diabetics, showed reduction of body weight, hemoglobin (Hb), hematocrit, hematimetry, insulin, TNF-α and IL- 6 (heart) and increased glycemia, body weight / left kidney weight, serum urea, creatinine, Phosphatase Alkaline, lactate dehydrogenase (LDH) and lactate levels, tumor necrosis factor (TNF) interleukin (IL) -6 and IL-10 (in the kidney); diabetic mice treated with insulin (1 IU / 300 mg/dL glycemia) in relation to untreated diabetic animals promoted increased body weight, serum insulin levels and blood glucose lowering, serum urea levels and TNF-α ratio / IL-10 (heart); diabetic animals treated with cholecalciferol (800 IU/day), in relation to untreated diabetic animals, exhibited increased serum levels of 25-hydroxycholecalciferol [25 (OH) D], Hb, hematocrit, hematimetry, IL-10 (heart) and reduced IL-6, IL-10, TNF-α and EPO (kidney);insulin-treated diabetic animals compared to diabetic animals supplemented with cholecalciferol exhibited an increase of body weight, serum urea, IL-6 and TNF-α (heart) and a reduction of glycaemia, serum lactate levels, IL-6, TNF- α, IL-10 and EPO (kidney); animals that received both hormones, compared to animals treated with insulin exhibited an increase of insulin and lactate serum levels; diabetic animals that received both hormones, compared to diabetic animals treated with cholecalciferol, exhibited an increase of 25(OH)D and insulin serum levels, and a reduction of IL-10, TNF-α/IL-10 and TNF-α/IL-6 ratios (heart); diabetic animals that received both hormones, compared to diabetic animals not supplemented with cholecalciferol, exhibited an increase of insulin and reduced urea serum levels and reduced renal and hepatic TNF-α/IL-6 ratios; LPS-stimulated RAW 264.7 cells and treated with 100 nM cholecalciferol exhibited greater CYP27B1 expression and reduced release of inflammatory mediators when compared to the LPS-stimulated group. However, the same effect was not observed in PM. Taken together, the results suggest that: 1) in diabetic animals, cholecalciferol may modulate hematological parameters and that insulin may improve renal function as well as recovery of body weight; 2) cholecalciferol can be metabolized by RAW 264.7 cells and modulate the immune response triggered by LPS.
69

Conceptual design for automated coal preparation

Muralidharan, K. January 1982 (has links)
No description available.
70

K problematice poznání distribuce kamenných surovin na území západního okruhu kultury s lineární keramikou v neolitu / Remarks on raw material distribution in western LbK Culture region during the Neolithic

Pavlíčková, Eva January 2012 (has links)
This diploma thesis deals with the distribution of lithic raw materials in the Neolithic, whereas the main interest was focused on the area of Germany. The dispersion of chipped and polished stone artefacts in time and space was studied on the basis of available literature. The first part of this work presents existing knowledge about spreading specific types of lithic raw materials. The second part introduces sites from different federal states with finds of chipped and polished stone industry from which was it possible to determine the composition of lithic raw materials collections. The database is part of this work and includes catalogue of sites.

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