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(181 - 200 of 5,257)
Pages
- Title
- Gerry-meandering: An Assessment of the Congressional District Model of Depository Allocation (preprint): AhrensGriffinedrev2
- Creator
- Ahrens, Aric G., Griffin, Luke A.
- Date
- 2003-06
- Description
-
The preprint of a published article dealing with the effect of allocating Federal Depositories by Congressional district. Conclusions drawn...
Show moreThe preprint of a published article dealing with the effect of allocating Federal Depositories by Congressional district. Conclusions drawn include the fact that due to redistricting that occurs after each decennial census, over time some districts may have within their boundaries a greater number than the two depositories that Congressional district allocation was intended to produce. Likewise, over time shifting boundaries of districts have created districts that have no depositories whatsoever.
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- Title
- EXPERIMENTAL STUDY, TIME-RESOLVED OBSERVATION, AND ANALYSIS OF NANOSECOND LASER ABLATION AND LASER-INDUCED PLASMA
- Creator
- Zhou, Yun
- Date
- 2013, 2013-05
- Description
-
For lasers, there exist many current and potential competitive applications in the areas of manufacturing, materials processing, and so on....
Show moreFor lasers, there exist many current and potential competitive applications in the areas of manufacturing, materials processing, and so on. Nanosecond (ns)-pulsed lasers are often seen in these applications. This dissertation presents the experimental study, time-resolved observation and analysis of nanosecond laser ablation and laser-induced plasma due to ablation, and the analysis is based on physics-based numerical models. Specifically, the following topics have been studied: (1). Plasma induced by ablation using long-duration nanosecond laser pulse Plasma is often produced in laser-material interactions, and may play an important role in many laser-based or laser-assisted technologies, such as laser shock peening (LSP), laser micromachining (through the laser ablation process), laser-induced breakdown spectroscopy (LIBS), and laser propulsion, etc. However, despite the previous work in the literature, the study is still limited for the plasma induced by the ablation process using long nanosecond laser pulses (with durations on the order of ~100 ns). In this dissertation, investigations have been performed on this kind of plasma through fast photography (imaging) and emission spectroscopy techniques, and the experimental results have been analyzed using physics-based computational models. Based on the investigations, the following major interesting findings have been obtained under the investigated conditions: (i) Two high radiation intensity regions are observed in the plasma, and one of them disappears soon after laser pulse ends. The research work shows that this phenomenon is related to the vaporization process from the target surface and the confinement effect of the ambient air. (ii) Laser-induced plasma xvii backward growth phenomenon occurs for target ablation using 100-ns laser pulses, but not for that using 200-ns pulses. The investigation shows that the underlying mechanism is the backward growth of the boundary of the high temperature region without actual backward motion of vapor material. (iii) Under the studied conditions, the core region of the plasma (~100 μm above the laser-ablated target) has relatively low temperatures as compared to some other regions of the plasma, which contradicts the common intuition. (2). Semiconductor ablation utilizing infrared (IR) nanosecond laser pulses Semiconductor micromachining through laser ablation may have the advantages of high spatial resolution, high processing efficiency, good flexibility, and no tool wear. However, most of the prior investigations in the literature on ns laser ablation of semiconductors often employ lasers at the ultraviolet (UV) or visible wavelength. The work using IR ns lasers is limited, but IR ns lasers may often have lower cost and require less external energy consumption to produce the same average laser power output. In this dissertation, the ablation of semiconductors using IR ns lasers has been studied through time-resolved observations (fast photography) and the results have been analyzed utilizing physics-based numerical models. The research work shows that the ablation mechanism under the studied conditions is the surface vaporization process during the early stage followed by the subsequent liquid ejection process that occurs at a later time. The research work and analysis shows that the underlying mechanism for the observed liquid ejection should be due to the spatial gradient of the pressure exerted on the target surface, instead of phase explosion. (3). Laser-induced backside ablation (LIBA) of sapphire with IR ns laser pulses xviii LIBA may potentially provide a good solution for high-quality and highefficiency micromachining of wide-band-gap dielectrics (WBGD). However, the prior work on LIBA of sapphire (which is a very important WBGD material) using low-cost IR ns lasers has been rarely reported. This kind of work has been carried out in this dissertation, and the investigation shows that under the studied conditions LIBA can produce very high material removal efficiency and reasonably good quality of machining without obvious chemical contamination coming from the employed backing layer. The ablation rate and damage threshold are measured under different laser parameters, and the research work may provide useful information for the applications of LIBA in practical areas using IR ns lasers that may often have relatively lower cost than UV or visible ns lasers.
PH.D in Mechanical and Aerospace Engineering, May 2013
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- Title
- The yield of acetic acid as influenced by temperature in wood distillation
- Creator
- Marx, Walter L.
- Date
- 2009, 1913
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/yieldofaceticaci00marx
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 22
- Title
- Image-based Indexing and Classification in Image Databases
- Creator
- Agam, Gad, Frieder, Ophir
- Date
- 2012-03-20, 2010-08-31
- Description
-
The invention enables the digital management of large scale image databases, to efficiently classify and index image data independent of...
Show moreThe invention enables the digital management of large scale image databases, to efficiently classify and index image data independent of language. Complex processing requirements are required only on reduced and operably small subsets of the entire collection, thereby effectively scaling large document collections. Embodiments of the present invention provide image-based classification and retrieval of documents based on image recognition, e.g., signatures, logos, stamps, or word-spotting; in documents within real time for large datasets such as in the millions of documents.
Sponsorship: Illinois Institute of Technology
United States Patent
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- Title
- Apparatus for Generating Generally Uniform Compression in High-Viscosity Fluids
- Creator
- Venerus, David C., Kompani, Mandana
- Date
- 2009-05-11, 1999-06-29
- Description
-
An apparatus for generating generally uniform compression forces over a film of a relatively low-viscosity liquid by passing the low-viscosity...
Show moreAn apparatus for generating generally uniform compression forces over a film of a relatively low-viscosity liquid by passing the low-viscosity liquid through a porous plate, from an upstream face to a downstream face of the porous plate. The porous plate has a specified porosity and arrangement of the through holes or other pores that results in forming a uniform pressure through and uniform compression forces over a film of the low-viscosity liquid that is at or near the upstream face of the porous plate. The apparatus of this invention results in homogeneous deformation of a material, such as molten polymer, polymer solution, multiphase polymer systems, asphalts or foods.
Sponsorship: Illinois Institute of Technology
United States Patent
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- Title
- Howell Mountain Winery: Jury_Boards
- Creator
- Duggan, Michael
- Date
- 2012-04-21, 2012-05
- Description
-
Howell Mountain is a distinct and unique location in the heart of Napa Valley California. The 45 acres site rests on the mountain’s south west...
Show moreHowell Mountain is a distinct and unique location in the heart of Napa Valley California. The 45 acres site rests on the mountain’s south west slopes and is planted with high quality grapes used in the production of red wine. When the fog rolls off the ocean and into the Napa Valley, the weather on Howell Mountain is generally sunny and cool. The appellation owes its distinctive climate to the fact that it is positioned high above the valley floor. The program includes both the wine production facilities and the hospitality facilities for visitors. The driving concept of the project is to merge those two, often opposing, programmatic elements. From west to east, the site has a 43% grade change. By designing a gravity flow winery, this facility can take advantage of that significant slope.
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- Title
- Spraying Process
- Creator
- Bradstreet, Samuel W., Griffith, James S.
- Date
- 1956-09-18
- Description
-
Sponsorship: Armour Research Foundation of Illinois Institute of Technology
United States Patent
- Title
- North Carolina State University Rapid Transit Center: NC_State_Rapid_Transit_Center_Boards
- Creator
- Scott, Phillip
- Date
- 2012-05, 2012-05
- Description
-
North Carolina State University is one of the leading land grant institutions and public research universities in the country. However, its...
Show moreNorth Carolina State University is one of the leading land grant institutions and public research universities in the country. However, its rapidly growing size and required travel distance in-between campuses necessitate drastically improved transit connections. Current plans are in place for the construction of a rapid transit corridor through campus along with commuter and light rail transit. The Master’s Project will focus on the main multimodal center for this transportation network, the North Carolina State University Rapid Transit Center.
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- Title
- Method and Means for Energizing Magnetic Recorder Heads
- Creator
- Camras, Marvin
- Date
- 1944-06-13
- Description
-
Sponsorship: Armour Research Foundation
United States Patent
- Title
- FIELD AND PHOTO-EMISSION IN A SHORT-PULSE, HIGH-CHARGE CESIUM TELLURIDE RF PHOTOINJECTOR
- Creator
- Wisniewski, Eric E.
- Date
- 2014, 2014-05
- Description
-
A new high-charge RF gun is now operating at the Argonne Wakefield Accelerator (AWA) facility at Argonne National Laboratory (ANL). The 1.5...
Show moreA new high-charge RF gun is now operating at the Argonne Wakefield Accelerator (AWA) facility at Argonne National Laboratory (ANL). The 1.5 cell 1.3 GHz gun uses a Cesium telluride photocathode driven with a 248 nm laser to provide short-pulse, high charge electron beams for the new 75 MeV drive beamline. The high-gradient RF gun (peak field on the cathode > 80MV/m) is a key piece of the facility upgrade. The large Cs2Te photocathode (diameter > 30 mm) was fabricated in-house. The photo-injector will be used to generate high-charge, short pulse, single bunches (Q > 100 nC) and bunch-trains (Q>1000 nC) for wakefield experiments, typically involving dielectric-loaded accelerating structures. Details of the photocathode fabrication process and the results of associated diagnostic measurements are presented, including QE measurements and work function measurements performed with a Kelvin probe. Field-emitted dark current from the Cs2Te cathode was measured during RF conditioning and characterized. Fowler-Nordheim plots of the data are presented and compared to similar measurements made using a copper cathode in the initial phase of conditioning. The results for cesium telluride exhibited non-linear regions within the Fowler-Nordheim plots similar to previous experimental results for other p-type semiconductors. Results of quantum efficiency (QE) studies are presented with the cathode operating in both single and bunch-train modes. QE uniformity and lifetime studies are presented. During commissioning, the cesium telluride photocathode produced bunch-charge of 100 nC, breaking the previous record. No evidence of bunch-train position-dependence of QE was found when generating four-bunch trains with total charge up to 200 nC.
PH.D in Physics, May 2014
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- Title
- Method and Apparatus for Detecting Collisions on and Controlling Access to a Transmission Channel
- Creator
- Campbell, Graham M., Xu, Wenxin
- Date
- 2009-05-14, 2001-09-18
- Description
-
A method for controlling multiple access of a transmission channel wherein a plurality of different patterns are assigned to a plurality of...
Show moreA method for controlling multiple access of a transmission channel wherein a plurality of different patterns are assigned to a plurality of sending stations so that each sending station corresponds to a unique pattern, preferably a pattern represented by a Binomial coefficient. Each unique pattern is transmitted from a corresponding sending station to the transmission channel by way of a control minislot. Ternary feedback is received from the control minislot. A summation of different patterns within each control minislot are analyzed to detect whether a collision exists between the different patterns within each control minislot.
Sponsorship: Illinois Institute of Technology
United States Patent
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- Title
- SAFETY TRAINING IN CONSTRUCTION
- Creator
- Demirkesen, Sevilay
- Date
- 2011-11-29, 2011-12
- Description
-
The construction industry is one of the most hazardous industries. Therefore, the ways to reduce the number of risks have been a concern for...
Show moreThe construction industry is one of the most hazardous industries. Therefore, the ways to reduce the number of risks have been a concern for construction companies. Safety training is considered as one of the most efficient ways of improving safety record. Therefore, this study aimed to describe the best safety training methods and the most efficient organization in safety training. The study also aimed to show how to take best safety measures to protect construction workers. In this thesis study, a questionnaire was conducted in order to investigate the achievement of safety learning, challenges in a safety training program and the methods of improving safety record. Thus, the questionnaire was e-mailed to 400 contractors in US. The data collected also indicated the importance of safety training in companies’ success in the industry. Additionally, this study presents recommendations on how companies could improve their safety record.
M.S. in Civil Engineering, December 2011
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- Title
- Method for the Preparation of Titanium Tetrachloride
- Creator
- Schossberger, Frederic V.
- Date
- 1958-10-21
- Description
-
Sponsorship: Armour Research Foundation of Illinois Institute of Technology
United States Patent
- Title
- IN VITRO ASSAYS FOR ASSESSING THE IMPACT OF PROCESSING ON THE ALLERGENIC POTENTIAL OF MILK ALLERGENS
- Creator
- Zhao, Yuhui
- Date
- 2014, 2014-07
- Description
-
A better understanding of how processing may affect the allergenicity of proteins will allow a more accurate allergen risk assessment and...
Show moreA better understanding of how processing may affect the allergenicity of proteins will allow a more accurate allergen risk assessment and achieve a greater success in food allergy management. To determine whether food processing can affect the allergenic potential of proteins, immunochemical methods are commonly used, however, these methods are not able to determine changes in the proteins’ ability to elicit allergic reactions. Although food challenge studies are the gold standard for determining the allergenicity of proteins, such studies are seldom performed due to ethical reasons and the difficulty in recruiting a sufficient number of study participants. In recent years, a number of mediator release assays have been developed to measure the allergenic potential of food proteins in vitro. How these cell-based assays can be used to assess the impact of thermal or other processing conditions on the allergenic potential of proteins remains to be determined. This study evaluated the use of sensitized rat basophilic leukemia (RBL) cells for assessing the impact of boiling on the allergenic potential of milk allergens by measuring changes in the proteins’ ability to induce cell degranulation and the release of β-hexosaminidase. RBL-2H3 cells sensitized with rat IgEs that were specifically raised against NIST non-fat milk standard reference material, β-lactoglobulin (BLG), α-lactalbumin (ALA) and α-casein (αCAS) were challenged with various concentrations of each allergen in its native and processed (boiled in PBS for 10 min) forms. Cell degranulation caused by the allergen was monitored by measuring the release of β-hexosaminidase. All allergens (NIST milk, BLG, ALA, and αCAS) were able to induce the release of β-hexosaminidase, up to 43.1%. A decrease in % release of β-hexosaminidase was observed when cells were challenged with a decreasing concenration xi of the ALA and milk allergens. Boiling of nonfat milk, ALA, BLG and αCAS caused an increase in the % release of β-hexosaminidase from sensitized cells across antigen concentrations from 10-6 mg/mL to 1 mg/mL. In conclusion, this study demonstrated that the in vitro mediator release assay method may serve as a useful model to evaluate the impact of thermal processing on the allergenic potential of milk allergens.
M.S. in Food Safety and Technology, July 2014
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- Title
- BIOLOGICAL STRATEGIES FOR ENHANCEMENT OF LIQUID FUELS: SULFUR REMOVAL FROM PETROLEUM AND BIOETHANOL PRODUCTION
- Creator
- Wang, Jia
- Date
- 2013, 2013-12
- Description
-
Rhodococcus baikonurensis CW25 was transformed with the Rhodococcus erythropolis strain IGTS8 desulfurization operon (dszABC, which encodes...
Show moreRhodococcus baikonurensis CW25 was transformed with the Rhodococcus erythropolis strain IGTS8 desulfurization operon (dszABC, which encodes the enzymes of the “4S” desulfurization pathway) or this operon modified to contain a synthetic cysteine-methionine rich “sulpeptide” gene (S1) (dszAS1BC). The two CW25 derivatives were subjected to directed evolution to select faster growing cells using the key 4S pathway substrate dibenzothiophene (DBT) as the sole source of sulfur. Data of cell doubling times verified the success of selection of cultures with increasingly rapid growth. The desulfurization activities of resting cells of early passages demonstrated improvements, and the highest activity of the dszAS1BC-bearing CW25 derivative was 115% higher than that of the CW25 derivative without S1. In addition, a trend of initial high activity was followed by a decrease in subsequent passages. Rates of DBT metabolism of growing cells demonstrated a different trend, probably because the activity of growing cells concurrently reflects the activity of DszABC enzymes and the growth rates of the recombinants. Dry cell weights fluctuated during the evolution process, probably because of variations in the efficiency of the conversion of the sulfur in DBT into sulfite, then into sulfate or biomass, or, for the S1-bearing cells, because the secretion of the S1 peptide from cells might have variable efficiency. A mixed culture of two Paenibacillus species (“W” and “Y”) was isolated that can metabolize DBT at temperatures up to 54 ºC. Strain Y is the only one of the two with desulfurization activity, while strain W enhances the desulfurization ability of Y. The W-Y culture may be a useful starting point for selection of desulfurization cultures with even greater thermal stability. xiii Ethanologenic Escherichia coli strain FBR5 was compared with Vitreoscilla hemoglobin (VHb)-expressing FBR5 (TS3) regarding the concentrations of ATP, NAD+, NADH, NAD+/NADH ratio; and growth and ethanol production at various points during growth. The significant finding was that the NAD+/NADH ratio for TS3 was lower in early growth, but higher in later growth compared to that for FBR5. This is probably because more NADH was required by TS3 for its enhanced ethanol production and VHb-related increased respiration under microaeration conditions.
PH.D in Biology, December 2013
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- Title
- Apparatus and Method for In Situ Controlled Heat Processing of Hydrocarbonaceous Formations with a Controlled Parameter Line
- Creator
- Bridges, Jack E.
- Date
- 2009-05-08, 1985-02-12
- Description
-
A system and method provide for preferential in situ heating of earth formations. A plurality of elongated conductive electrodes are emplaced...
Show moreA system and method provide for preferential in situ heating of earth formations. A plurality of elongated conductive electrodes are emplaced in earth formations in respective spaced rows bounding a particular volume of the earth formations and forming a transmission line, preferably a triplate line, extending in the direction of the electrodes with the particular volume of the earth formations providing a dielectric medium between respective rows of electrodes. Electromagnetic energy is supplied to the transmission line at a frequency at which the spacing between respective rows is less than about twice the skin depth at the frequency of the applied energy. Reactance means are disposed along respective electrodes to provide predetermined effective transmission line characteristics to develop a predetermined heating pattern in the earth formations. The reactance means may be reactances disposed discretely between sections of respective electrodes. The reactance means may also be disposed between respective electrodes and the earth formation, as by a dielectric coating. A heating pattern may be developed to heat hydrocarbon rich deposits preferentially.
Sponsorship: IIT Research Institute
United States Patent
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- Title
- Gerry-meandering: An Assessment of the Congressional District Model of Depository Allocation (preprint)
- Creator
- Ahrens, Aric G., Griffin, Luke A.
- Date
- 2003-06
- Description
-
The preprint of a published article dealing with the effect of allocating Federal Depositories by Congressional district. Conclusions drawn...
Show moreThe preprint of a published article dealing with the effect of allocating Federal Depositories by Congressional district. Conclusions drawn include the fact that due to redistricting that occurs after each decennial census, over time some districts may have within their boundaries a greater number than the two depositories that Congressional district allocation was intended to produce. Likewise, over time shifting boundaries of districts have created districts that have no depositories whatsoever.
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- Title
- Financial Incubators, India: presentation 26 april
- Creator
- Shah, Shruti
- Date
- 2010-05-01, 2010-05
- Title
- MATHEMATICAL MODELING OF POLY(ETHYLENE GLYCOL) DIACRYLATE HYDROGEL SYNTHESIS VIA VISIBLE LIGHT FREE-RADICAL PHOTOPOLYMERIZATION FOR TISSUE ENGINEERING APPLICATIONS
- Creator
- Lee, Chu-yi
- Date
- 2013, 2013-05
- Description
-
Crosslinked hydrogels of poly(ethylene glycol) diacrylate (PEGDA) have been extensively used as scaffolds for applications in tissue...
Show moreCrosslinked hydrogels of poly(ethylene glycol) diacrylate (PEGDA) have been extensively used as scaffolds for applications in tissue engineering. In this thesis, PEGDA hydrogels are synthesized using visible light free-radical photopolymeriza- tion (λ = 514 nm) in the presence of the visible light photosensitive dye, EosinY, the co-initiator, triethanolamine (TEA), a comonomer, N-vinyl pyrrolidone (NVP), a crosslinking agent, PEGDA, and an optional PEG monoacrylate monomer that contains the cell adhesive ligand YRGDS. The incorporation level of the YRGDS lig- and as well as the physical and mechanical properties of these hydrogels dictate cell behavior and tissue regeneration. These hydrogel properties may be tuned through variations in polymerization conditions. The goal of this thesis was to develop a math- ematical model for PEGDA hydrogel formation which predicts the incorporation level of YRGDS and the crosslink density of hydrogel as a variety of polymerization con- ditions. This model provides insight into the process of hydrogel crosslinking and in effectively guiding the experimental design of these scaffolds for tissue engineering applications. To accomplish this task two major components comprised the studies of this thesis. The first component involved an investigation of the visible light photo- initiation mechanism of EosinY and TEA, and the second component involved the develop of a hydrogel synthesis model and its validation. Experiments and modeling were used to determine an expression for the rate of initiation of the EosinY/TEA initiation system and to propose a photoinitiation mechanism. In Chapter 2, exper- imental data and parameter fitting were utilized to obtain an empirical expression for the rate of initiation. However, this empirical expression did not consider the ef- fect of inhomogeneous light distribution which is present in this experimental system. The dynamics of light absorption during polymerization were measured under differ- xiv ent conditions in order to gain insight into the kinetic photoinitiation mechanism as well as the rate of initiation. In Chapter 3, a mechanism for this photo-initiation was proposed. Using this mechanism the light absorption dynamics accounting for inhomogeneous light distribution were simulated which were found to be in an agree- ment with the light absorption measurements shown in Chapter 2. Further validation of this proposed mechanism was achieved from polyNVP conversion measurements. This photo-initiation mechanism was implemented in the hydrogel model. In Chapter 4, the hydrogel synthesis model was developed based on the kinetic approach of the method of moments combined with the Numerical Fractionation technique. The model was used to predict the dynamics of hydrogel properties such as gel fraction, crosslink density, and RGD incorporation under various polymerization conditions. Model predictions were compared with experimental data. Three sets of experiments were conducted. In the first set of experiments where hydrogels were formed in the absence of Acryl-PEG-RGD, the total double bond concentration was kept constant while varying the compositions of NVP and PEGDA. The model and the experiments showed a maximum crosslink density for an acrylate to double bond ratio of 0.5 to 0.6. This is related to the synergistic cross-propagation between NVP and PEGDA, which results in an increase in the rate of polymerization leading to higher crosslink density. In the second set of experiments, hydrogels were formed in the presence of Acryl-PEG-RGD to investigate its incorporation as well as the hydrogel crosslink density. The model showed reasonable agreement with the experimental data and in some cases the predicted RGD deviated from the experimental measurements due to changes in volume upon swelling. The effect of swelling was not considered by the model. The calculated crosslink densities were compared with the inverse swelling ratios from the experiments. The reduction of free volume due to the space occupied xv by the unreacted pendant double bonds was not considered by the model. This reduc- tion of free volume affected the apparent swelling ratio obtained from experiments thus resulting in the observed mismatch between the experimental trends and the predicted crosslink density by the model. In the third set of experiments, additional crosslink density measurements were conducted using a PEGDA macromer of lower molecular weight (MW = 575 Da.). The experiments were performed in the absence of Acryl-PEG-RGD. Few cases were not accurately predicted since the model did not consider the reduction in the concentration of available pendant double bonds when gelation occurs. Among the three set of experiments, the hydrogel synthesis model offers reasonable predictions for most of the experimental cases. This model can be used as a guide for experimen- tally designing PEGDA hydrogels with the desired properties for tissue engineering applications.
PH.D in Chemical and Biological Engineering, May 2013
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