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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.
1041

Vliv vlhkosti materiálu na tepelné vlastnosti rukavic / The influence of moisture on the thermal properties of the gloves

Janíčková, Žaneta January 2019 (has links)
This diploma thesis is focused on the assessment of the influence of moisture on the thermal properties of the gloves. The first part of the thesis deals with the research of topics related to the given issue as well as with the derivation of the computational relations needed for evaluation of experimental measurements. The main focus of the work lies on defining the hypotheses and experiments that are used to verify the influence of moisture on the thermal resistance of gloves. As for the experimental part, it describes the individual methods of moistening the gloves from which the moistening through the air humidity and the moistening by the immersion were analysed. To verify the suitability of selected moistening methods, the tested glove samples were measured on the thermal manikin both in a dry and a moistened state under the conditions defined by ČSN EN 511 and ČSN EN ISO 15831 standards. Individual states were repeatedly measured and afterwards the progresses of thermal resistance depending on time were graphically displayed. The thesis also includes analysis of measurement uncertainties as well as evaluation of measurement repeatability. From the obtained results, both the defined hypotheses and theoretical assumptions about the decrease of the thermal resistance of a textile material due to the influence of moisture were confirmed in the conclusion of the diploma thesis.
1042

Tile Drainage, Beds, and Fe-EDDHA Application Effect on Soybean Production

Holmes, Lucas Connor January 2018 (has links)
Eastern North Dakota has received excessive rainfall events since 1995, and soils are prone to waterlogging. This research evaluated the effects of subsurface tile drainage, raised beds, and iron-chelate (Fe-EDDHA) seed-application on iron-deficiency chlorosis (IDC) incidence in soybean [Glycine max (L.) Merr.], soybean growth, and yield, across six environments during 2013 and 2014. Tile drainage without beds increased soybean yield and reduced IDC by 11%. Beds resulted in more vigorous plants with 9% more biomass and increased soybean yield by 6%. There was no yield advantage to using both tile and raised beds within the same field. The Fe-EDDHA reduced plant population and IDC expression, increased plant biomass, but did not result in a yield increase. Farmers are encouraged to consider utilizing raised beds as a means to mitigate excess water. Additional research is needed to determine the cause of lower established plant density after seed application with Fe-EDDHA. / Minnesota Soybean Research and Promotion Council / North Dakota Soybean Council / DuPont Pioneer
1043

Experimental Studies on Infiltration/Soil-Water Movement Processes and Green-AMPT Modeling

Sande, Leif Andrew January 2011 (has links)
Experimental studies on infiltration/soil-water movement processes are vital to better understanding movement of soil-water in the vadose zone. The objective of this experimental research was to investigate infiltration/soil-water movement processes utilizing laboratory experiments and computer modeling. Small scale laboratory soil box infiltration experiments were conducted and utilized for the improved parameterization of the Green-Ampt (GA) saturated moisture content parameter to produce an effective moisture content parameter (Be) for utilization in a modified GA model. By incorporating ⊖e values into GA modeling, modeling results showed greatly improved wetting front prediction across different soil conditions. A new soil packing method was proposed for replicating complex microtopographical surfaces with uniform bulk densities in laboratory soil box experiments which proved efficient and effective at accomplishing both objectives. A rainfall simulator and an instantaneous-profile laser scanner were used to simulate rainfall and quantify surface microtopography for experiments. The results clearly show the effect of microtopography on infiltration and soil-water movement characteristics. This offers valuable insight into infiltration/soil-water movement processes as affected by different soil and surface microtopographic conditions. / National Science Foundation (Grant No. EAR-0907588)
1044

THE IMPACT OF DIETARY FIBER AND SUCROSE ALTERNATIVES ON TEXTURE PERCEPTION OF COOKIES

Sarah L Pitts (11565889) 22 November 2021 (has links)
<p>Low moisture baked goods (cookies, biscuits, etc.) are known for their high sugar content, low water content, and characteristic texture. The added sugar in baked goods has been a concern of health advocates due to the negative health implications of overconsumption of sugar. To minimize these health implications and support healthier food products, the replacement of sugar, sucrose, in low moisture baked goods with alternative sweeteners is of interest. The goal of this study was to improve understanding on how sweetener alternatives and dietary fiber interact with cookie ingredients and the subsequent cookie texture compared to sucrose containing cookies to aid in developing health-conscious low moisture baked goods.</p><p> The replacement of sucrose with sucrose replacers (SRs) encompassing a variety of structural and physicochemical properties (high fructose corn syrup (HFCS), amorphous sucrose, maltitol, allulose, isomalt, Benefiber, Miralax, fructooligosaccharides (FOS), and isomalto-oligosacchrides (IMO)) in wire-cut cookies was investigated in terms of starch thermal properties, model cookie formulations, and sensory descriptive analysis. Starch thermal properties were investigated using differential scanning calorimetry (DSC) while wire-cut cookie parameters were analyzed through a<sub>w</sub>, color (<i>a, b, L</i>), moisture loss, cookie dimensions (height, width, length), and cookie hardness (N) assays. Sensory descriptive analysis was used to ascertain texture perception of wire-cut cookies through five attributes (hardness, fracturability, pastiness, cohesiveness, and crumbliness).</p> The onset gelatinization temperature (T<sub>gel</sub>) was increased to a greater extent than sucrose by Miralax and FOS, and to the same extent by IMO, maltitol, and Benefiber at high concentrations (60%w/w). The SRs which performed similar to sucrose in wire-cut cookie baking (spread, moisture loss, hardness) and texture intensity ratings were amorphous sucrose, maltitol, and allulose. No significant differences in descriptive analysis intensity scores were found in crumbliness, cohesiveness, and pastiness between SRs and sucrose formulated wire-cut cookies. FOS, IMO, and Benefiber displayed significantly larger fracture intensity scores compared so sucrose and isomalt cookies were significantly less hard than sucrose cookies. Principal component analysis (PCA) related SRs effect on starch gelatinization, cookie baking properties, and descriptive analysis intensity scores, and indicated the mostly likely candidates for use in reduced sugar cookies are maltitol and allulose.
1045

Kinetika kontinuálního měření obsahu vlhkosti velmi jemných partikulárních materiálů. / Kinetics of the continual measurement of the actual fine particulates moisture content.

Mayerová, Kateřina January 2012 (has links)
This thesis deals with the continual measurement of the hydrated lime moisture content on the principle of spectral measurements. The theoretical part describes the basic principles of the infrared spectroscopy, Fourier transformation and near infrared spectroscopy, which are used in the process of the spectroscopy measurement of fine particulates moisture content. The practical part of the work describes experiments and the evaluation of moisture hydrated lime measuring results, using gravimetric method and NIR spectroscopy in both the laboratory conditions and the conditions of operation production of hydrated lime as well. The part of the work monitors the spectroscopy measurement moisture values as the dependence on the optical quality of hydrate limes and the process conditions of the measurements.
1046

Sušení mokrých povrchů vzduchovými proudy / Wet surfaces drying using air streams

Gusnarová, Hana January 2010 (has links)
Diploma thesis submit processing and evaluation of experiment which was made at University of Hertfordshire. Aim of this experiment was practically confirm and compare efficiency of drying bottles with blower and compressor. The next purpose was to suggest solution against recondensation on dry surface of bottles. Diploma thesis involves also economy calculation. In the diploma thesis was described issues of drying and condensation, realized analysis of drying equipment and methods of air conditioning. As the most suitable and the most cost effective way of drying was at the base on experiment and energy and economy calculation chosen tested turbo blower 587. As the solution, against recondenzation was created anticondensation tunnel. As the most suitable way for condition the dew point inside the tunnel for require value was chosen desiccant rotor Munters.
1047

Zjišťování a specifikace neodstranitelných vad a poruch staveb / Detection and Specifications of Unrectifiable Defects and Failures of Building Structures

Tesaříková, Martina January 2010 (has links)
The diploma thesis deals with problems of identification and specification of insurmountable impairments with a focus on moisture. The aim of my work is generally explain what the fault and failure, what is their cause, and the overall approach in this area. Next determine the difference between removable and irremovable defect. Part of this work is a chapter devoted to surveys of buildings, which are an integral part in detecting defects, failures and their root structures. Another section is devoted to the main subject of work - moisture, approach this issue and the problems caused by moisture in the structure. At the end of this chapter is about ways of reducing the moisture in structures. The last section is on the case (the object affected moisture) approach procedure for identifying and assessing these impairments in practice.
1048

Snímač kondenzované vlhkosti / Sensor of condensed moisture

Krejčí, Jakub January 2017 (has links)
This master thesis deals with measuring condensed moisture in constructions using measuring moisture porosity material. Market research was performed and were made sensors own construction based on capacity principle and their attributes were measured. In this thesis is also described method, which is used for calibration for conditions in building constructions causing condensation of water.
1049

Framtagning och applicering av förbrukningsindikator på fuktabsorbent : Ett produktutvecklingsarbete för Smellwell AB

Wallin Berg, Ida January 2018 (has links)
Detta examensarbete är genomfört på uppdrag av företaget Smellwell AB och ämnar en produktutveckling av deras produkter. Smellwell tillverkar och säljer fuktabsorberande påsar med en fräsch doft för användning i skor och annan träningsutrustning. Målet med detta arbete var att ta fram och applicera en förbrukningsindikator på deras fuktabsorbenter. Det är idag svårt att avgöra när produkten är förbrukad vilket kan leda till att många kunder använder produkten för länge. Detta kan leda till en sämre användarupplevelse. Syftet med arbetet var därför att öka kundvärdet genom att kunna erbjuda kunden ett sätt att alltid veta när det är dags att byta ut sin produkt för maximal effekt.  Problemet delades upp i två delproblem som löstes var för sig. Först togs det fram en lämplig indikator och sedan skapades tre appliceringsmetoder för indikatorn genom en produktutvecklingsprocess. I arbetet med att ta fram appliceringsmetoderna användes två olika 3D-skrivare som hjälpmedel, en Makerbot Replicator+ och en Objet Eden 260v. Arbetet resulterade i en 6-månaders tidsindikator från det engelska företaget Timestrip® UK Ltd och tre olika indikatorhållare för olika appliceringsmetoder på fuktabsorbenten. Resultaten har utvärderats av en fokusgrupp och förslag på kostnad och framtida tillverkningsmetod har angetts. Koncept 2 och koncept 3 fick bäst betyg i utvärderingen och kommer rekommenderas till Smellwell att gå vidare med. / This bachelor thesis has been carried out on behalf of Smellwell AB and aims at product development of their product. Smellwell manufactures and sells moisture absorbing bags with a fresh scent for use in shoes and sports equipment. The aim of this work was to produce and apply a consumption indicator to their moisture absorbers. Today it is difficult to determine when the product is consumed, which can lead to many customers using the product for to long. This can lead to a poorer user experience. The purpose of the work is therefore to increase customer value by offering the customer a way to always know when it is time to replace their product for maximum effect. The problem was divided into two sub-problems that were resolved separately. First, an appropriate indicator was developed and three application methods were created through a product development process. In the process of developing the application methods two different 3D-printers were used, a Makerbot Replicator+ and an Objet Eden 260v. The work resulted in a 6-month’s time indicator from the English company Timestrip® UK Ltd and three different holders for application at different positions on the moisture absorber. The results have been evaluated by a focus group and proposals for cost and future manufacturing methods have been specified Concept 2 and Concept 3 got the best rating in the evaluation and will be recommended to Smellwell to proceed with. / <p>Betyg 181031</p>
1050

Implications of Bio-modification on Moisture Damage Mechanisms in Asphalt Binder Matrix

January 2020 (has links)
abstract: Bio-modification of asphalt binder brings significant benefits in terms of increasing sustainable and environmental practices, stabilizing prices, and decreasing costs. However, bio-modified asphalt binders have shown varying performance regarding susceptibility to moisture damage; some bio-oil modifiers significantly increase asphalt binder's susceptibility to moisture damage. This variability in performance is largely due to the large number of bio-masses available for use as sources of bio-oil, as well as the type of processing procedure followed in converting the bio-mass into a bio-oil for modifying asphalt binder. Therefore, there is a need for a method of properly evaluating the potential impact of a bio-oil modifier for asphalt binder on the overall performance of asphalt pavement, in order to properly distinguish whether a particular bio-oil modifier increases or decreases the moisture susceptibility of asphalt binder. Therefore, the goal of this study is a multi-scale investigation of bio-oils with known chemical compositions to determine if there is a correlation between a fundamental property of a bio-oil and the resulting increase or decrease in moisture susceptibility of a binder when it is modified with the bio-oil. For instance, it was found that polarizability of asphalt constituents can be a promising indicator of moisture susceptibility of bitumen. This study will also evaluate the linkage of the fundamental property to newly developed binder-level test methods. It was found that moisture-induced shear thinning of bitumen containing glass beads can differentiate moisture susceptible bitumen samples. Based on the knowledge determined, alternative methods of reducing the moisture susceptibility of asphalt pavement will also be evaluated. It was shown that accumulation of acidic compounds at the interface of bitumen and aggregate could promote moisture damage. It was further found that detracting acidic compounds from the interface could be done by either of neutralizing active site of stone aggregate to reduce affinity for acids or by arresting acidic compounds using active mineral filler. The study results showed there is a strong relation between composition of bitumen and its susceptibility to moisture. This in turn emphasize the importance of integrating knowledge of surface chemistry and bitumen composition into the pavement design and evaluation. / Dissertation/Thesis / Doctoral Dissertation Civil, Environmental and Sustainable Engineering 2020

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