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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.
271

Evaluation of DNA Quality of Beer Ingredients

Ramberg, Anna January 2006 (has links)
<p>The project aim is to determine if good quality DNA can be extracted from barley, malt and hop, ingredients used in beer brewing. Good quality DNA is important in DNA fingerprinting techniques which can be used for identification of ingredients. The 3 methods tested are the cetyltrimethylammonium bromide (CTAB) method, QIAGEN DNeasy Plant Mini Kit and Meyer’s method as published in 1996 with QIAGEN DNeasy Plant Mini Kit in combination. To evaluate the DNA quality after extraction we used 3 different techniques:</p><p>(i) spectrophotometry to estimate purity by using the ratio A260/A280; (ii) agarose gel electrophoresis after DNA extraction to determine the success of the extraction and evaluate the amount of high molecular weight DNA and degradation; and (iii) the polymerase chain reaction with 4 different primer pairs, together with agarose gel electrophoresis, to determine if the extracted DNA could be used in downstream applications, see the effect of inhibitors and estimate the fragmentisation of the DNA. The results achieved using the above mentioned methods were then used to evaluate the success of each of the extraction methods in their function of extracting high quality DNA from barley, malt and hop as well as determining whether the treatment of the ingredients has an effect on the DNA quality.</p>
272

Ductile steel plate shear walls with PEC columns

Dastfan, Mehdi 11 1900 (has links)
The behavior of steel plate shear walls under the effects of lateral loads depends on the stiffness of the surrounding frame members. Previous research has quantified the minimum required stiffness of columns in the middle stories of steel plate shear wall systems. As the columns of the steel plate shear wall system are subjected to both large axial forces and bending moments, use of composite columns is a viable option in this system. Among the different types of composite columns, the recently developed partially encased composite columns with built-up steel sections have some advantages over other types of composite columns and thus their performance as columns in steel plate shear wall systems needs to be studied. In the first part of this research, a numerical and analytical study has developed a new design parameter and determined the minimum required stiffness of end beams in end panels of the steel plate shear wall system. The effect of the rigidity of the frame connections on the uniformity of the tension field has also been studied in this part. The second part of this research includes two large scale tests on steel plate shear walls with built-up partially encased composite (PEC) columns. One of the test specimens was modular and the other one used reduced beam sections in the frame. The results of the tests show that the columns were stiff enough to anchor the infill plate. The PEC columns in these tests performed in a ductile manner. The overall system behavior was ductile, stable and the specimens showed good seismic behavior and redundancy. Based on the results and observations of this research, design recommendations for PEC columns used as the vertical boundary members of steel plate shear walls are provided. / Structural Engineering
273

Performance-Based Reliability Analysis and Code Calibration for RC Column Subject to Vehicle Collision

Sharma, Hrishikesh 2012 May 1900 (has links)
Infrastructure and transportation facilities have increased rapidly over the years. The progress has been accompanied by an increasing number of vehicle collisions with structures. This type of collision might lead to the damage, and often, collapse of the structure. In reinforced concrete (RC) structures, columns are usually the most vulnerable members exposed to collisions. However, the existing design guidelines and provisions for protection of these members against collision of vehicles are not adequate. In particular, the desired behavior and the associated performance levels of a structure during a vehicle collision are not defined. Therefore, there is need to assess the vulnerability of structures against such collisions. This research aims to develop a framework for the performance-based analysis and design of RC columns subject to vehicle impact. It helps mitigate maximum damage and achieve an economical design. The current research takes into account performance-based analysis and design as opposed to only collapse prevention design. The performance level is tied to the impact levels to estimate the reliability of the RC column for the desired performance objectives. The performance-based probabilistic models for estimating shear resistance of RC column and shear demand on RC column are developed. The reliability of the RC column subject for selected performance levels is evaluated. The performance levels are tied to impact demand and load and resistance factors are proposed to achieve desired performance objectives of the RC column subject to vehicle collision.
274

Evaluation of DNA Quality of Beer Ingredients

Ramberg, Anna January 2006 (has links)
The project aim is to determine if good quality DNA can be extracted from barley, malt and hop, ingredients used in beer brewing. Good quality DNA is important in DNA fingerprinting techniques which can be used for identification of ingredients. The 3 methods tested are the cetyltrimethylammonium bromide (CTAB) method, QIAGEN DNeasy Plant Mini Kit and Meyer’s method as published in 1996 with QIAGEN DNeasy Plant Mini Kit in combination. To evaluate the DNA quality after extraction we used 3 different techniques: (i) spectrophotometry to estimate purity by using the ratio A260/A280; (ii) agarose gel electrophoresis after DNA extraction to determine the success of the extraction and evaluate the amount of high molecular weight DNA and degradation; and (iii) the polymerase chain reaction with 4 different primer pairs, together with agarose gel electrophoresis, to determine if the extracted DNA could be used in downstream applications, see the effect of inhibitors and estimate the fragmentisation of the DNA. The results achieved using the above mentioned methods were then used to evaluate the success of each of the extraction methods in their function of extracting high quality DNA from barley, malt and hop as well as determining whether the treatment of the ingredients has an effect on the DNA quality.
275

Investigation of Operating Parameters Influencing Electrostatic Charge Generation in Gas-Solid Fluidized Beds

Giffin, Amanda 02 February 2011 (has links)
Electrostatic charge generation in gas-solid fluidized beds is a significant industrial problem. Associated problems include particle agglomeration and particle wall fouling. In the polymerization industry this may result in "sheets" of fused polymer, due to exothermic reaction causing the melting of the polymer, which can fall off and block the distributor plate disrupting fluidizing gas flow. Additionally, blockage of the catalyst feed or the polymer removal system can take place or the product can become non-uniform. All of these problems require shut-down of the reactor which results in lost production time. While this phenomena has been identified for many years, the mechanisms involved are not well understood, especially wall fouling and the distribution of charge within the bed. Isolation of individual parameters such as hydrodynamics, operating conditions, and material involved is necessary to evaluate how each parameter impacts charge generation during fluidization. In this thesis, the fluidization system consisted of a stainless steel column, two online Faraday cups, and a retractable distributor plate. This system allowed for the simultaneous measurement of charge within different regions of the bed: the entrained fine particles, the particles adhered to the column wall, and the bulk of the bed. Additionally, mass and particle size distributions were measured and images of the layer of particles adhered to the column wall were taken for comparison. This allowed for a charge distribution comparison and evaluation of wall fouling. Three different parameters were investigated: duration of fluidization, column wall material, and relative humidity of fluidizing gas. Fluidization time was studied for 15, 30, 60, 120, 180, and 360 min; relative humidity was investigated for 0%, 20%, 40%, 60%, and 80% relative humidity. Both fluidization time and relative humidity were evaluated at four different fluidization gas velocities, two each in the bubbling and slugging flow regimes. Column wall material was evaluated for a stainless steel and carbon steel column at two gas velocities, one each in the bubbling and slugging flow regimes. Fluidization time was found to influence wall fouling in the bubbling flow regime as the particle layer continued to build as fluidization progressed. In the slugging flow regime, the particle layer developed within 15 minutes of the onset of fluidization. The bubbling flow regime was shown to have a greater capacity for charge generation than the slugging flow regime. This was due to the vigorous mixing in the bubbling flow regime resulting in more particle-particle interactions. Column wall material was shown to influence wall fouling in the slugging flow regime due to the differences in surface roughness of the columns. This was due to the particle-wall contacts resulting in frictional charging which is the predominant charging mechanism in this flow regime. Charge was also impacted in the bubbling flow regime in those particles that were adhered to the column wall. Relative humidity was found to influence wall fouling at the lowest gas velocity tested. However, variations in generation of charge occurred at all fluidization gas velocities tested; the charge-to-mass ratios for the particles adhered to the column wall in the slugging flow regime decreased with high relative humidities. This was due to either the formation of a water film layer on the column wall or instantaneous surface water films on the particles throughout fluidization.
276

Experimental Characterization of the Thermal, Hydraulic and Mechanical (THM) Properties of Compost Based Landfill Covers

Bajwa, Tariq Mahmood 10 January 2012 (has links)
Landfills are considered to be one of the major sources of anthropogenic methane (CH4) emissions in the environment. A landfill biocover system optimizes environmental conditions for biotic CH4 consumption that controls the fugitive and residual emissions from landfills. A compost material has more oxidation potential in comparison to any other material due to its high porosity, organic content, free flux for gases and water holding capacity. Thermal, hydraulic, bio – chemical and mechanical (THMCB) properties are important factors that can significantly affect the performance of biocover material with regards to CH4 oxidation potential as well as structural stability. Technical data on the thermal, hydraulic and mechanical (THM) properties of compost based biocover materials are quite limited. Hence, a detailed experimental program has been carried out at the University of Ottawa to study the THM properties and behaviour of compost biocover material by conducting experimental tests on small compost samples as well as by performing column experiments. The test results indicate that lower water content (dry of optimum for compaction curve) shows more free air space (FAS) in comparison to higher water content. The compost has almost the same shear strength for various initial water contents and dry unit weights; however, it settles and swells more at higher water content than lower water content per mechanical test results. The thermal and hydraulic properties of compost are a function of the compaction degree in addition to various other parameters. It is also found that the THM properties of compost are strongly coupled and the degree of saturation greatly affects the FAS.
277

P-Cycle-based Protection in Network Virtualization

Song, Yihong 25 February 2013 (has links)
As the "network of network", the Internet has been playing a central and crucial role in modern society, culture, knowledge, businesses and so on in a period of over two decades by supporting a wide variety of network technologies and applications. However, due to its popularity and multi-provider nature, the future development of the Internet is limited to simple incremental updates. To address this challenge, network virtualization has been propounded as a potential candidate to provide the essential basis for the future Internet architecture. Network virtualization is capable of providing an open and flexible networking environment in which service providers are allowed to dynamically compose multiple coexisting heterogeneous virtual networks on a shared substrate network. Such a flexible environment will foster the deployment of diversified services and applications. A major challenge in network virtualization area is the Virtual Network Embedding (VNE), which aims to statically or dynamically allocate virtual nodes and virtual links on substrate resources, physical nodes and paths. Making effective use of substrate resources requires high-efficient and survivable VNE techniques. The main contribution of this thesis is two high-performance p-Cycle-based survivable virtual network embedding approaches. These approaches take advantage of p-Cycle-based protection techniques that minimize the backup resources while providing a full VN protection scheme against link and node failures.
278

A Study Of Settlement Of Stone Columns By Finite Element Modeling Through Case Histories

Yardim, Cemre Harzem 01 January 2013 (has links) (PDF)
Stone column technique is mostly used to reinforce soft cohesive soils. Settlements are decreased under foundations and bearing capacity is increased. This study initially focuses on a comprehensive review of literature about stone column reinforced soils. Afterwards, numerical modeling of stone column reinforced soft clays is done. Three different cases are chosen on different foundation soils mainly soft clays. Parametric studies are done to determine influence of parameters on settlement reduction ratio under three different foundation conditions. Analyses are converted to two dimensional conditions and this conversion is also compared within the scope of this study. Settlement reduction ratio response to variation in parameters revealed similar results under three different foundation conditions.
279

Investigation of Operating Parameters Influencing Electrostatic Charge Generation in Gas-Solid Fluidized Beds

Giffin, Amanda 02 February 2011 (has links)
Electrostatic charge generation in gas-solid fluidized beds is a significant industrial problem. Associated problems include particle agglomeration and particle wall fouling. In the polymerization industry this may result in "sheets" of fused polymer, due to exothermic reaction causing the melting of the polymer, which can fall off and block the distributor plate disrupting fluidizing gas flow. Additionally, blockage of the catalyst feed or the polymer removal system can take place or the product can become non-uniform. All of these problems require shut-down of the reactor which results in lost production time. While this phenomena has been identified for many years, the mechanisms involved are not well understood, especially wall fouling and the distribution of charge within the bed. Isolation of individual parameters such as hydrodynamics, operating conditions, and material involved is necessary to evaluate how each parameter impacts charge generation during fluidization. In this thesis, the fluidization system consisted of a stainless steel column, two online Faraday cups, and a retractable distributor plate. This system allowed for the simultaneous measurement of charge within different regions of the bed: the entrained fine particles, the particles adhered to the column wall, and the bulk of the bed. Additionally, mass and particle size distributions were measured and images of the layer of particles adhered to the column wall were taken for comparison. This allowed for a charge distribution comparison and evaluation of wall fouling. Three different parameters were investigated: duration of fluidization, column wall material, and relative humidity of fluidizing gas. Fluidization time was studied for 15, 30, 60, 120, 180, and 360 min; relative humidity was investigated for 0%, 20%, 40%, 60%, and 80% relative humidity. Both fluidization time and relative humidity were evaluated at four different fluidization gas velocities, two each in the bubbling and slugging flow regimes. Column wall material was evaluated for a stainless steel and carbon steel column at two gas velocities, one each in the bubbling and slugging flow regimes. Fluidization time was found to influence wall fouling in the bubbling flow regime as the particle layer continued to build as fluidization progressed. In the slugging flow regime, the particle layer developed within 15 minutes of the onset of fluidization. The bubbling flow regime was shown to have a greater capacity for charge generation than the slugging flow regime. This was due to the vigorous mixing in the bubbling flow regime resulting in more particle-particle interactions. Column wall material was shown to influence wall fouling in the slugging flow regime due to the differences in surface roughness of the columns. This was due to the particle-wall contacts resulting in frictional charging which is the predominant charging mechanism in this flow regime. Charge was also impacted in the bubbling flow regime in those particles that were adhered to the column wall. Relative humidity was found to influence wall fouling at the lowest gas velocity tested. However, variations in generation of charge occurred at all fluidization gas velocities tested; the charge-to-mass ratios for the particles adhered to the column wall in the slugging flow regime decreased with high relative humidities. This was due to either the formation of a water film layer on the column wall or instantaneous surface water films on the particles throughout fluidization.
280

Experimental Characterization of the Thermal, Hydraulic and Mechanical (THM) Properties of Compost Based Landfill Covers

Bajwa, Tariq Mahmood 10 January 2012 (has links)
Landfills are considered to be one of the major sources of anthropogenic methane (CH4) emissions in the environment. A landfill biocover system optimizes environmental conditions for biotic CH4 consumption that controls the fugitive and residual emissions from landfills. A compost material has more oxidation potential in comparison to any other material due to its high porosity, organic content, free flux for gases and water holding capacity. Thermal, hydraulic, bio – chemical and mechanical (THMCB) properties are important factors that can significantly affect the performance of biocover material with regards to CH4 oxidation potential as well as structural stability. Technical data on the thermal, hydraulic and mechanical (THM) properties of compost based biocover materials are quite limited. Hence, a detailed experimental program has been carried out at the University of Ottawa to study the THM properties and behaviour of compost biocover material by conducting experimental tests on small compost samples as well as by performing column experiments. The test results indicate that lower water content (dry of optimum for compaction curve) shows more free air space (FAS) in comparison to higher water content. The compost has almost the same shear strength for various initial water contents and dry unit weights; however, it settles and swells more at higher water content than lower water content per mechanical test results. The thermal and hydraulic properties of compost are a function of the compaction degree in addition to various other parameters. It is also found that the THM properties of compost are strongly coupled and the degree of saturation greatly affects the FAS.

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