Search results

Title: Building science measurements in the Hospital Microbiome Project
Creator: Stephens, Brent
Date: 2014, 2014
Description: Sponsorship: Alfred P. Sloan Foundation’s program on the Microbiology of the Built Environment (Grant No. 2012-10-04)

Title: SYSTEMWIDE INTERSECTION SIGNAL TIMING OPTIMIZATION SIMULTANEOUSLY MINIMIZING VEHICLE AND PEDESTRIAN DELAYS
Creator: Roshandeh, Arash Moradkhani
Date: 2013, 2013-07
Description: The ever-growing traffic volume especially in urban areas stretches the transportation system to be operated at near or exceeding capacity and...
Show moreThe ever-growing traffic volume especially in urban areas stretches the transportation system to be operated at near or exceeding capacity and causes congestion. Expanding system capacity and effectively utilizing available capacity could help reduce traffic congestion. In most of cases, adding extra travel lanes in dense urban street networks is not feasible any more due to land scarcity. This study introduces a new method for signal timing optimization that is carried out by adjusting green splits of AM peak, PM peak, and rest of the day timing plans for each signalized intersection in the network without changing the existing cycle lengths and signal coordination to minimize total vehicle and pedestrian delays per cycle. The proposed method contains a basic model that handles vehicle delays only and an enhanced model that simultaneously addresses vehicle and pedestrian delays using two different pedestrian delay estimation methods. Both models are incorporated into an agent-based regional travel demand forecasting tool for detailed traffic assignments using data on Chicago regional travel demand, traffic counts, geometric designs, and signal timing plans for major intersections in the Chicago Central Business District (CBD) street network. The computational experiment reveals that vehicle delays in the CBD area could reduce by 10 percent when only considering vehicle delays and 5 percent when simultaneously considering vehicle and pedestrian delays for signal timing optimization. Considering the intersections safety analysis, it has been found that signals timing optimization in all four areas combined without considering pedestrian delays decreased different crash types under various severities for multiple vehicle collisions as well as vehicle-pedestrian ones. Taking care of both vehicles and pedestrians delay xvi vii simultaneously, using HCM method, just a very few situations represent slight increases in crash frequencies and all other cases indicate crash reductions. Compared with the sensitivity analysis results using the HCM method for calculating pedestrian delays in the enhanced model applications, the Levinson method produces different results even though crash frequency reduction trends are almost the same as HCM method results.
PH.D in Civil Engineering, July 2013
Show less

Title: AN INVESTIGATION INTO STABILITY OF TUBE AND COUPLER SCAFFOLDS SUBJECT TO SEISMIC LOADS
Creator: Najafabadi, Aram Zare
Date: 2012-11-23, 2012-12
Description: Temporary structures are structures that are set up for applications in relatively short time periods, most notably category of which are...
Show moreTemporary structures are structures that are set up for applications in relatively short time periods, most notably category of which are scaffolds that are built in two types: supported and suspended. Tube and coupler scaffolding systems are supported types and are commonly used in nuclear industry’s applications. This study evaluates the behavior of this type of scaffolding system due to the effect of dead, live, i.e. weight of workers and equipment, and lateral earthquake loads applied on the structure. Consistent with OSHA dimensional requirements, six different configurations ranging from 1 to 3 stories and 1 to 2 bay scaffoldings have been selected for this study. Using a finite element analysis, the significance of all gravity loads, as well as potential seismic loads on the safety and stability of aforementioned scaffold types was studied. The seismic acceleration level at which the failure occurs was determined for four failure criteria. These criteria are: (1) the structural member yield failure; (2) the structural member buckling failure; (3) the system sliding failure; and (4) the system overturning (tip-over) failure. The analysis results show that the most critical failure mode for all configurations of tube and coupler scaffolds studied in this thesis occurred due to instability and as result of sliding. No overstress or buckling failure was observed to occur prior or concurrent to this failure. This finding reaffirms that this type of scaffolds has considerable sufficient capacity to resist their intended loads yet are vulnerable to instability because of sliding. With regards to the effect of number of bays and stories on the critical earthquake level, it was observed that as the number of scaffold stories increases, the critical earthquake level becomes smaller except for the case of the 1-bay scaffold for the 2- and xii 3-story configurations. Addition of an extra bay to a simple 1-bay scaffold configuration does not considerably improve the earthquake level at which the sliding failure occurs. With regards to time of failure, addition of stories to a scaffold configuration delays the failure occurrence in all cases except for the case of the 2-bay scaffold and addition of a bay does significantly delay the occurrence of failure for 1- and 2-story scaffolds, about 6 second for 1-story scaffolds, and 8 seconds for 2-story scaffolds. However, this improvement is negligible for 3-story scaffolds. In general, addition of a bay postpones the failure time. The evaluation of stress levels in all various scaffolding elements suggests that increasing the number of bays and/or stories does not generally affect the induced stresses in beams. In addition, the study shows that buckling and overturning (uplift) effects have very minimal effect on the failure of tube and coupler scaffolds.
M.S. in Civil Engineering, December 2012
Show less

Title: Arched dams
Creator: Szeszychi, Ignatius Leo., Zack, Raymond R.
Date: 2009, 1911
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/archeddams00szes
Thesis (B.S.)--Armour Institute of Technology, 1911 B.S. in Civil Engineering, 1911

Title: PROJECT SCHEDULING USING OPTIMIZED FINANCING
Creator: Alavipour, Seyyed Mohammadreza
Date: 2017, 2017-07
Description: Contractors need financing throughout a project, mainly due to retainage, which is the money that the owner withholds to make sure that the...
Show moreContractors need financing throughout a project, mainly due to retainage, which is the money that the owner withholds to make sure that the project is performed properly by the contractor. Even if an owner does not withhold retainage, financing is still necessary because the periodic payments made by the owner are usually delayed. All pertinent studies conducted so far have considered only one source of financing without any consideration of different sources and types of financing, times of cash provisions, interest rates, and repayment options. Actually, if one assumes a predetermined credit limit and one source of financing, as past researchers have done, the optimal financing cost and the schedule that satisfies all constraints may be different than when several sources of financing and undetermined credit limit are considered. The main objective of this research is to focus on the optimization of financing cost by developing a financing optimization model based on different financing alternatives. Far lower financing cost and higher profit are obtained by using the proposed model compared to all models developed in past research. The research is conducted in four stages of development. In Stage 1, a financing optimization model is developed for a schedule that uses normal (not accelerated) activities, and early activity start and finish times. This model can be used before the contract is signed to offer the lower bid or can be used after the contract is signed to obtain higher profit. In Stage 2, the time-cost tradeoff algorithm is added to the model developed in Stage 1, considering accelerated activities between the crash and normal durations. In Stage 3, the model developed in Stage 2 is augmented by considering variable activity start times. Finally, in Stage 4, the model developed in Stage 3 is further improved by expanding time-cost tradeoff to allow for time extensions beyond the contract duration. All models developed in these four stages provide not only minimum financing cost, but also the ideal work schedule that achieves minimum total cost and maximum profit. Moreover, these models provide specific timings for borrowing and repaying funds.
Ph.D. in Civil Engineering, July 2017
Show less

Title: ADVANCING KNOWLEDGE OF INDOOR AEROSOL SOURCES, FATE, TRANSPORT, AND CONTROL
Creator: Azimi, Parham
Date: 2016, 2016-12
Description: Recent evidence suggests that particulate matter (of both indoor and outdoor origin) is one of the most important airborne pollutants driving...
Show moreRecent evidence suggests that particulate matter (of both indoor and outdoor origin) is one of the most important airborne pollutants driving adverse health effects worldwide. Despite our understanding of major indoor aerosol sources that contribute to adverse health effects across the population, gaps in our knowledge of some aspects of the sources, fate, transport, and control of indoor aerosols still remain. This dissertation focuses on filling three major gaps related to indoor aerosols. The first objective of this dissertation is to improve knowledge of the impacts of particle filtration in central heating, ventilation, and air-conditioning (HVAC) systems on fine particles smaller than 2.5 μm in diameter (i.e., PM2.5) and ultrafine particles smaller than 100 nm in diameter (i.e., UFPs) of outdoor origin that penetrate into the indoor environment. Results demonstrate that higher-efficiency HVAC filters can significantly reduce indoor proportions of outdoor PM2.5 and UFPs inside residences, but home vintage, climate zone, and ventilation strategy strongly influence the outcomes due to widely varying air exchange rates, HVAC system runtimes, and sources of ventilation air. The second objective of this dissertation is to improve knowledge of emissions and control of particulate matter from a recently established source of indoor pollutants: desktop three-dimensional (3D) printers. Median estimates of time-varying UFP emission rates ranged from ~108 to ~1011 #/min across all tested combinations, varying primarily by filament material and, to a lesser extent, bed temperature. It was also shown that UFP concentrations within close or moderate proximity to some desktop 3D printer and filament combinations can exceed recommended exposure levels. The most effective control strategies for reducing pollutant concentrations emitted from desktop 3D printers wereinstalling a high-flow spot ventilation system and operating the printer in a sealed enclosure with high efficiency gas and particle filtration. Finally, the third objective of this dissertation is to improve knowledge of the fate, transport, and control of infectious diseases in indoor environments through mathematical modeling of bioaerosol transmission and infection risk. Results demonstrate that Recirculating HVAC filtration can achieve risk reductions at lower costs of operation than equivalent levels of outdoor air ventilation, particularly for MERV 13-16 filters. It was also shown that in addition to the biological characteristics of respiratory pathogens, human activities, interzonal airflows, and physical properties of bioaerosols can substantially impact the infection transmission risk. Further, the dominant pathway for influenza transmission indoors under most conditions was airborne transmission. Finally, estimations of the back-calculated quanta generation rate for influenza viruses were directly in line with the existing data gathered from prior epidemiology studies.
Ph.D. in Environmental Engineering, December 2016
Show less

Title: PUBLIC LITERACY ON SUSTAINABLE DEVELOPMENT
Creator: Panchal, Avani P.
Date: 2011-07-19, 2011-07
Description: Reports suggest that Chicago is one of the leading US cities with respect to sustainability and, in order to promote sustainability in a city...
Show moreReports suggest that Chicago is one of the leading US cities with respect to sustainability and, in order to promote sustainability in a city like Chicago, it is imperative that the residents are aware of factors associated with sustainable development and contribute towards its advancement. Majority of the research conducted so far, does not examine the non-expert level of sustainability understanding. This thesis investigates the public literacy on sustainable development by conducting a survey and analyzing the generated database. The statements posed in the survey do not demand technical education but assess the non-expert resident literacy of sustainability by asking relevant subjects. The survey consists of four demographic questions (participants‟ gender, age, level of education and annual income), fifteen conceptual statements and five opinion statements, based on sustainability. The aim is to find a relation, if any, between the respondents‟ demographics and their responses to the survey. The database generated from the survey of 353 randomly selected individuals, is analyzed by four different statistical methods, which are arranged in increasing order of complexity – (i) descriptive statistics and z-test for proportions, (ii) contingency tables and Pearson chi-square test, (iii) exploratory factor analysis and (iv) multinomial logistic regression. The outcome of the statistical analyses suggests that approximately 50% of the participants have accurately responded to the survey and the non-expert resident does not know the definitions to pertinent sustainability concepts. Additionally, survey responses have a strong association with the participants‟ age. There is a weak association between answers and the respondents‟ gender and annual income. In spite of higher than average participants with a college degree, the level of education has a negligible relation with survey responses. Thus, it is necessary to increase the awareness and educate non-experts about sustainable development. It is promising to observe that the responses to the opinion statements suggest that individuals are willing to contribute towards sustainability provided they are educated about it. Nonetheless, the willingness to contribute requires action and without societal support, it is not possible to promote sustainability, which requires increased understanding and knowledge and willingness to act appropriately.
M.S. in Environmental Engineering, July 2011
Show less

Title: ASSESSMENT OF STRUCTURAL MATERIALS BY HIGH TEMPERATURE INSTRUMENTED INDENTATION
Creator: Gan, Bin
Date: 2012-12-03, 2012-12
Description: This is an ideal place for me to express my gratefulness to my Ph.D. advisor, Prof. Sammy Tin, who has offered me the financial support and...
Show moreThis is an ideal place for me to express my gratefulness to my Ph.D. advisor, Prof. Sammy Tin, who has offered me the financial support and tremendous freedom in doing research. From working with me through publications and thesis, mentoring me what constitutes a professional and high quality work, nurturing my patience, to giving me advice on how to deliver an insightful presentation, Prof. Tin puts his effort in helping me on every small step that I need to make, as I gradually become more experienced in research and start to make a few achievement along the way. I am deeply indebted to Prof. Tin’s vision, guidance and sustained support. I would like to thank Prof. Philip Nash, Prof. Sheldon Mostovoy and Prof. Sudhakar Nair for being the committee member of my thesis defense, and offering me so many invaluable suggestions. The indispensable help from Russ Janota, the faculty and staff in the MMAE department is acknowledged. The enjoyable interaction with Mengtao, Qizheng, Matt, and other TPTC friends helps me in various aspects. I would like to thank Dr. Hideyuki Murakami and Dr. Takahito Ohmura for hosting me in NIMS. The experience had broadened my horizon and tremendously enhanced my capabilities to conduct independent research. In addition, the research collaboration with Prof. Julia R. Greer and Dr. Robert Maass on freestanding Ni3Al nanoparticles is also fully acknowledged. Furthermore, I am grateful to Prof. Qiang Feng and Prof. Roman Nowak. Their constant support, encouragement, mentoring and nurturing have a profound influence on me. This thesis is dedicated to my beloved parents, Jinlong Gan and Yuxiang Lai, who have built the fortitude into my mind. I also thank my sisters, Liping Gan and Lihong Gan, for their sustained support. Their love and understanding enable me to have a peaceful mind that makes this study possible. I also feel grateful to the deep love and endless patience from Xiaomo Li and the support from her parents.
PH.D in Materials Science and Engineering, December 2012
Show less

Title: Building the Iowa Industrial Reformatory for Females
Creator: Holmboe, J. A.
Date: 2009, 1917
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/buildingiowaindu00holm
Thesis (B.S.)--Armour Institute of Technology

Title: NUTRIENT REMOVAL FROM SECONDARY EFFLUENTS USING REACTIVE FILTRATION
Creator: Bhupal, Gurmanpreet Singh
Date: 2015, 2015-07
Description: Simultaneous removal of dominant forms of nitrogen and phosphorous present in secondary effluents was studied with reactive filtration as the...
Show moreSimultaneous removal of dominant forms of nitrogen and phosphorous present in secondary effluents was studied with reactive filtration as the treatment method. The selected media for filter bed included Granular Ferric Hydroxide (GFH), Calcite (C), Silica Sand (S), and Activated Alumina (A). The focus was to evaluate the performances of media blends GFH-C-S and A-C-S for removal of sRP and sNO3-N in lab scale batch and column experiments using secondary effluents provided by Calumet Water Reclamation Plant. The media blends performed better for sRP removal than sNO3-N removal with A-C-S being outperformed by GFH-C-S in batch experiments, and hence was not used for column experiments. The removal kinetic study using GFH-C-S showed 100% sRP removal rate and 45% NO3-N removal rate for an optimal contact time of 2 minutes, with latter showing gradual desorption after initial instant adsorption. The optimal adsorbent dosage for sRP was found to be 15g (1:1:1) whereas for NO3-N, the removal rates increased with an increase in adsorbent dosage. Column experiments with GFH-C-S gave an adsorption capacity of 1.8 mg/g for an equilibrium concentration of 0.1 mg P/L with breakthrough occurring after a throughput of 603 bed volumes.
M.S. in Environmental Engineering, July 2015
Show less

Title: SEISMIC COLLAPSE EVALUATION OF NON-DUCTILE CONCENTRICALLY BRACED FRAMES
Creator: Wen, Rou
Date: 2012-11-21, 2012-12
Description: More attentions have been paid on the Non-Ductile Concentrically Braced Frames (ND-CBFs) in low and moderate seismicity regions recently due...
Show moreMore attentions have been paid on the Non-Ductile Concentrically Braced Frames (ND-CBFs) in low and moderate seismicity regions recently due to their low ductility detailing requirements for design and construction. In this work, seismic collapse performances of two ND-CBFs are studied. One 3-story and one 9-story ND-CBF using small response modification coefficients (R=3) are designed firstly. Nonlinear finite element technologies are used to study the behaviors of local components. Practical analytical models for brace/gusset-plate assemblies and steel gravity frames are developed based on finite element simulations and engineering judgment. Three 2D structural models having increased local modeling complexity are developed for each braced frame. Nonlinear static pushover analyses on 3-story frames are conducted to get basic understandings of the damage evolution patterns and the interactions between main brittle braced frames and the steel gravity frames. Nonlinear dynamic analyses references the concepts of Incremental Dynamic Analysis are followed to investigate the seismic collapse responses of studied frames. The seismic assessments referenced the evaluation methods in FEMA P695 for ductile seismic load resisting frames through incremental dynamic analysis are carried out. Studied results show that Non-Ductile Concentrically Braced Frames would have little chance to prevent building collapse under severe ground motions. However, it seems that such buildings at least with low-to-moderate heights would have high probability of collapse prevention for up to moderate ground motions with conventional gravity framing systems used in modern steel buildings.
PH.D in Civil Engineering, December 2012
Show less

Title: SOLIDS ROLE IN TERTIARY CHEMICAL PHOSPHORUS REMOVAL BY ALUM
Creator: Maher, Chris
Date: 2013, 2013-12
Description: Chemical phosphorus (P) removal is commonly implemented in wastewater treatment to remove P to very low levels (
Show moreChemical phosphorus (P) removal is commonly implemented in wastewater treatment to remove P to very low levels (<0.1 mg P/L). The dose of precipitant (Al or Fe) needed is several times the stoichiometric dose in order to achieve a filtered effluent level of < 30 μg TP/L. The mechanistic basis for P removal using chemical precipitant addition is generally considered to be more than simple precipitation. The role of adsorption and/or complexation in removal of reactive or unreactive phosphorus to the already formed chemical precipitates or complexes has been investigated. Potential operational efficiency gains resulting from age of chemically precipitated solids and the recycle of these solids to the process stream was undertaken at the Iowa Hill Water Reclamation Facility which employs the DensaDeg® process (IDI, Richmond, VA) for tertiary chemical P removal. The effect of solids age was found to be insignificant over the solids retention time of 2 to 8 days, indicating that the solids were unaffected by the aging effects of decreasing porosity and surface acidity, and that the bulk of solids were retained in the clarifier blanket, hence providing no advantage in the removal mechanisms from increased concentration of solids. When solids recycle was redirected from the traditional location of the flocculation reactor to a point just prior to chemical addition in the chemical mixing reactor, lower effluent soluble P concentrations at lower molar doses of aluminum were achieved. At laboratory scale, the “spent” or “waste” chemical sludge showed high capacity and rapid kinetics for P sorption from real wastewater effluents. A number of scenarios were tested and the wide range of parameter values indicate that the sorption reaction is rather specific to the sludge and the process water matrix. x Saturation concentrations were in the range of 8 to 29 mg soluble reactive P/g solids. Higher saturation concentrations were found at higher temperatures. Ambiguous results were obtained for the effect of sludge age on capacity, implying dependence on either aging conditions or sample matrices. In all instances alum sludge produced without a coagulant aid polymer had a much higher capacity for P sorption than polymer based sludge. The reaction reached equilibrium in less than 10 minutes with 50% or greater removal within the first minute. Removal reactions were modeled well by nth order equations with n 3 and by exponential data fitting. Modeled as a sorption process, the pseudo-second order model presented by Ho and McKay in 1999 proved to be an excellent fit. Second order rate constants ranged approximately from 0.1 to 6 (g mg-1 min-1) depending on the P fraction examined, age of sludge, reaction temperature, and presence or absence of coagulant aid polymer in the sludge.
M.S. in in Environmental Engineering, December 2013
Show less

Title: Comparative designs of Gravity and Ambursen dams
Creator: Lyon, William K., Jr, Petersen, George W.
Date: 2009, 1921
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/comparativedesig00lyon
Thesis (B.S.)--Armour Institute of Technology;Includes folded leaves in back pocket...
Show morehttp://www.archive.org/details/comparativedesig00lyon
Thesis (B.S.)--Armour Institute of Technology;Includes folded leaves in back pocket Bibliography: leaf [4]
Show less

Title: Collective data on the treatment of sewage by the activated sludge process
Creator: Hammerman, M. A.
Date: 2009, 1920
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/collectivedataon00hamm
Thesis (B.S.)--Armour Institute of Technology;Bibliography: leaf 3

repository.iit

Search the repository

Pages

Pages

Enabled Filters

Refine Results

Type

Date

Subject

Creator

Rights