Search results

Title: Aeroacoustic Features of Coupled Twin Jets with Spanwise Oblique Shock-Cells
Creator: Panickar, P., Srinivasan, K., Raman, G.
Date: 2004-11-22
Publisher: Academic Press Ltd Elsevier Science Ltd
Description: This paper experimentally investigates the aeroacoustics of coupled twin jets of complex geometry. The study was motivated by the fact that...
Show moreThis paper experimentally investigates the aeroacoustics of coupled twin jets of complex geometry. The study was motivated by the fact that twin jet configurations that are commonly used in aircraft propulsion systems can undergo unpredictable resonant coupling resulting in structural damage. Further, nozzles with spanwise oblique exits are increasingly being considered for their aerodynamic and acoustic advantages, as well as stealth benefits. Although several studies have examined aspects of twin jet coupling, very little data is available on the coupling of jets from nozzles of complex geometry. Our study focuses on twin convergent nozzles with an aspect ratio of 7 with spanwise oblique exits operated over the fully expanded Mach number range from 1.3 to 1.6. The inter-nozzle spacing (s/h) was varied from 7.4 to 13.5. However, the focus remained on the lower spacing that is more representative of aircraft applications. Several interesting results have emerged from this study: (1) Coupling of twin nozzles with a beveled exit was observed only when the beveled edges faced each other and the nozzles formed a 'V' shape in the inter-nozzle region. Specifically, if the two beveled edges were oriented away from each other to form an arrowhead (W) shape no coupling was observed. (2) Despite the presence of spanwise antisymmetric, spanwise symmetric and spanwise oblique modes for the single nozzles, only the first two modes were evident in the coupling. (3) The symmetric coupling produced unsteady pressures in the inter-nozzle region that were up to 7.5 dB higher than the antisymmetrically coupled case. (4) Dynamic tests conducted by moving the nozzles apart while they were operating or by continuously changing the stagnation pressure at fixed inter-nozzle spacing revealed that coupling modes could co-exist at non-harmonically related frequencies. These dynamic tests reproduced the static test data. (5) The frequency of both coupling modes agrees with the higher order waveguide modes based on Tam's theory. (6) Differences in broadband shock noise between the 'V' and 'A' configurations were also documented. Our results provide an understanding of complex twin jet coupling and will serve as benchmark data for validating computational models. (C) 2003 Elsevier Ltd. All rights reserved.
http://dx.doi.org/10.1016/j.jsv.2003.10.011
Show less

Title: The potential importance of low luminosity and high energy at the LHC, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
Creator: White, Alan R.
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: Low luminosity runs at higher LHC energy could provide definitive evidence for an electroweak scale sextet quark sector of QCD that produces...
Show moreLow luminosity runs at higher LHC energy could provide definitive evidence for an electroweak scale sextet quark sector of QCD that produces electroweak symmetry breaking and dark matter within the bound-state S-Matrix of QUD - a massless, weak coupling, infra-red fixed-point, SU(5) field theory that might underly and unify the full Standard Model.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
Show less

Title: WIRELESS SCHEDULING IN MULTI-CHANNEL MULTI-RADIO MULTIHOP WIRELESS NETWORKS
Creator: Wang, Zhu
Date: 2014, 2014-07
Description: Maximum multi ow (MMF) and maximum concurrent multi ow (MCMF) in multi-channel multi-radio (MC-MR) wireless networks have been well-studied in...
Show moreMaximum multi ow (MMF) and maximum concurrent multi ow (MCMF) in multi-channel multi-radio (MC-MR) wireless networks have been well-studied in the literature. They are NP-hard even in single-channel single-radio (SC-SR) wireless networks when all nodes have uniform (and xed) interference radii and the positions of all nodes are available. This disertation studies maximum multi ow (MMF) and maximum concur- rent multi ow (MCMF) in muliti-channel multi-radio multihop wireless networks under the protocol interference model in the bidirectional mode or the unidirectional mode. We introduce a ne-grained network representation of multi-channel multi- radio multihop wireless networks and present some essential topological properties of its associated con ict graph. It was proved that if the number of channels is bounded by a constant (which is typical in practical networks), both MMF and MCMF admit a polynomial-time ap- proximation scheme under the protocol interference model in the bidirectional mode or the unidirectional mode with some additional mild conditions. However, the run- ning time of these algorithms grows quickly with the number of radios per node (at least in the sixth order) and the number of channels (at least in the cubic order). Such poor scalability stems intrinsically from the exploding size of the ne-grained network representation upon which those algorithms are built. In Chapter 2 of this dissertation, we introduce a new structure, termed as concise con ict graph, on the node-level links directly. Such structure succinctly captures the essential advantage of multiple radios and multiple channels. By exploring and exploiting the rich structural properties of the concise con ict graphs, we are able to develop fast and scalable link scheduling algorithms for either minimizing the communication latency or maximizing the (concurrent) multi ow. These algorithms have running time growing linearly in both the number of radios per node and the number of channels, while not sacri cing the approximation bounds. While the algorithms we develop in Chapter 2 admit a polynomial-time ap- proximation scheme (PTAS) when the number of channels is bounded by a constant, such PTAS is quite infeasible practically. Other than the PTAS, all other known approximation algorithms, in both SC-SR wireless networks and MC-MR wireless networks, resorted to solve a polynomial-sized linear program (LP) exactly. The s- calability of their running time is fundamentally limited by the general-purposed LP solvers. In Chapter 3 of this dissertation, we rst introduce the concept of interference costs and prices of a path and explore their relations with the maximum (concurrent) multi ow. Then we develop purely combinatorial approximation algorithms which compute a sequence of least interference-cost routing paths along which the ows are routed. These algorithms are faster and simpler, and achieve nearly the same approximation bounds known in the literature. This dissertation also explores the stability analysis of two link scheduling in MC-MR wireless networks under the protocol interference model in the bidirectional mode or the unidirectional mode. Longest-queue- rst (LQF) link scheduling is a greedy link scheduling in multihop wireless networks. Its stability performance in single-channel single-radio (SC-SR) wireless networks has been well studied recently. However, its stability performance in multi-channel multi-radio (MC-MR) wireless networks is largely under-explored. We present a stability subregion with closed form of the LQF scheduling in MC-MR wireless networks, which is within a constant factor of the network stability region. We also obtain constant lower bounds on the efficiency ratio of the LQF scheduling in MC-MR wireless networks under the protocol interference model in the bidirectional mode or unidirectional mode. Static greedy link schedulings have much simpler implementation than dy- namic greedy link schedulings such as Longest-queue-frst (LQF) link scheduling. However, its stability performance in multi-channel multi-radio (MC-MR) wireless networks is largely under-explored. In this dissertation, we present a stability subre- gion with closed form of a static greedy link scheduling in MC-MR wireless networks under the protocol interference model in the bidirectional mode. By adopting some special static link orderings, the stability subregion is within a constant factor of the stable capacity region of the network. We also obtain constant lower bounds on the throughput efficiency ratios of the static greedy link schedulings in some special static link orderings.
Ph.D. in Computer Science, July 2014
Show less

Title: Presentation to CARLI collections group
Creator: Uth, Charles
Date: 2010-04-13T13:25:24Z

Title: Chemical Process Performance Evaluation
Creator: Cinar, Ali, Palazoglu, Ahmet, Kayihan, Ferhan
Date: 2007
Publisher: CRC Press

Title: INDUSTRIAL UPGRADING IN KOREA
Creator: Woosiklee
Date: 2014, 2014-05
Description: One of the most difficult obstacles facing non-western nations is the issue of technology transfer. The main objective of this dissertation is...
Show moreOne of the most difficult obstacles facing non-western nations is the issue of technology transfer. The main objective of this dissertation is to analyze the how South Korea has succeeded through industrial upgrading through technology transfer in achieving the Han River Miracle- making it in 2011, the fourth largest economy in Asia and the 9th largest in the world. From 1910 to 1945, Korean modernization was continuously developed under the Japanese war economy and its military policy. Japanese capital, technology and entrepreneurs were transferred to Korea due to supplement the shortages of Japanese industries or to take advantage of the low labor costs in Korea in order to prepare for the Sino-Japanese War in 1936 and the Pacific War in 1941. There is no doubt that President Chung-Hee Park (1961-1979) was the architect of the Korean economic miracle. During his authoritarian regime, the government had played an important role in the creation and financing of the modern Korean industrial groupings, called the Chaebols. The government also intervened directly in the formation of their policies. In the 1980s, when the country embarked on financial liberalization, the degree of intervention started to decrease. And finally, the 1997 crisis will be examined, with special attention on the introduction of reforms required by the International Monetary Fund (IMF). In the industrial arena, the focus will be on the rationalization policies undertaken to increase the total factor productivity (TFP). It will cover the currently important industries of steel, automobiles and semiconductors, as well as those promising industries which have led the development of South Korea's knowledge-intensive economy. An integral part of the xi ii analysis will study the repercussions of the 1997 financial reforms on both the large and small and medium-size industries. Conventional wisdom assumes that it was under President Park's rule that South Korea had its first experience with industrialization. This assumption, however, ignores the significant industrialization that took place during the colonial period. It also does not take into account the admittedly limited industrial development that took place during the time before the 1961 coup d'état, when civilian governments were in charge. The dissertation would shed light on these overlooked periods.
PH.D in Management Science, May 2014
Show less

Title: Innovative Mapping (sequence unknown), IPRO 303 - Deliverables: IPRO 303 IPRO Day Presentation F09
Creator: Komoroski, Aaron, Mora, Andres, Sarraf, Basel, Kemp, Brandon, Duong, Cindy, Woodward, Frank, Suwada, Jerry, Michael, Mark, Sinha, Piyush, Glover, Richard, Mandrekar, Urba
Date: 2009-12
Description: The team worked to target the majority of mobile device users and give them an outlet to report any changes, mistakes or developments that...
Show moreThe team worked to target the majority of mobile device users and give them an outlet to report any changes, mistakes or developments that have been overlooked by NAVTEQ in the company's mobile mapping solutions. The team also worked to develop a solution that enables the average map user – men and women ages 18-35, students and tourists – to address these alterations in a simple, hassle-free way.
Sponsorship: NAVTEQ
Deliverables for IPRO 303: Innovative Mapping for the fall 2009 semester.
Show less

Title: THE RELATIONS OF LEADER EMPOWERING BEHAVIORS ON EMPLOYEE PERFORMANCE: MODERATED BY GENDER DYAD COMPOSITION
Creator: Zigun, David J
Date: 2016, 2016-07
Description: This study examined the possible moderating effect of gender dyadic composition on the relationship between Leadership Empowering Behaviors ...
Show moreThis study examined the possible moderating effect of gender dyadic composition on the relationship between Leadership Empowering Behaviors (LEBs) and employee performance across 221 supervisor-subordinate dyads in a Fortune 500 Midwestern U.S. company. The relationships between LEBs and employee performance moderated by gender dyadic composition were examined, as well as possible group differences of LEB ratings between gender dyad group membership. The goal of this study was to test the moderating role of gender dyadic composition on the relationship between LEBs and employee performance. This study obtained both supervisor ratings of employee performance and employee ratings of LEBs, allowing for the use of multi-source data. Results supported the expected relationship between LEBs and employee performance but neither indications of a moderating effect by gender dyads were found, nor were there group differences in perceptions of LEBs. This study adds to the existing literature because previous research has predominantly focused on examining employee perceptions of LEBs and related outcomes, but this was the first study to explore the potential moderating effect of gender dyads in this relationship. Implications of this study are explored.
M.S. in Psychology, July 2016
Show less

Title: DEVELOPMENT OF A TESTBED FOR STUDYING SECURITY ISSUES IN VOIP NETWORKS
Creator: Olawoye, Oladeji
Date: 2011-12-06, 2011-12
Description: VoIP is increasingly becoming an alternative to the traditional PSTN for Telephony this is as a result of certain advantages and services...
Show moreVoIP is increasingly becoming an alternative to the traditional PSTN for Telephony this is as a result of certain advantages and services offered by VoIP. VoIP will be considered able to fully replace PSTN if it can provide same or better Quality of Service and Security guaranty as PSTN. Delivering telephony services over (best-effort and connectionless) IP data network faces two main issues not experienced in PSTN, security and quality of service; security in the sense that telephone calls will be susceptible to attacks that are known in the Internet, quality of service in the sense that voice packets now have to compete with packets of other traffic for a limited bandwidth. Researches are ongoing in these two fields to make experience on VoIP similar to the traditional telephone. The focus of this thesis work is in the security aspect. SIP protocol has become one of the most popular signaling protocols used for VoIP, SIP architecture is an open architecture originally developed for trusted communications among trusted partners, and therefore much thought was not given to security. Adopting SIP as a main protocol used in VoIP in the Internet where there are where there are lots of hostile users calls for more ways to properly secure its use. The thesis work involves setting up of a SIP based VoIP network based on open source SIP telephony platforms to study various security issues in a SIP-Based VoIP network and experiment some proposed detection mechanism. The contribution of this work is to develop a graphical user interface in the UNIX environment using Java that makes the execution of the attack scenarios easy to carry out and observe.
M.S. in Electrical Engineering, December 2011
Show less

Title: Green Building Design Concept & Integration (sequence unknown), IPRO 335 - Deliverables: 1_IPRO 335 Midterm Presentation F09
Creator: Avanessian, Aris, Banda, Justine, Bergerson, Joshua, Burke, Jeffrey, Christo, Robert, Dexter, Eric, Kim, Kibum, Mey, Andrew, Okunaga, Jonathan, Razeq, Ali, Schaefer, Jacqueline, Thovar Leon, Adrian, Um, Hye
Date: 2009-12
Description: The scope of this IPRO project spans structural, architectural, foundation, HVAC, lighting and electric system designs, as well as building...
Show moreThe scope of this IPRO project spans structural, architectural, foundation, HVAC, lighting and electric system designs, as well as building cost estimating and professional ethics. The IPRO team will become informed about and apply principles associated with green design concepts, energy sustainability, post occupancy comfort, acoustic design issues, smart building concepts, health issues (abatement of mold- and allergy-causing agents), and safety considerations.
Deliverables for IPRO 335: Green Building Design Concept & Integration for the fall 2009 semester
Show less

Title: Study of ideal dry pipe valve
Creator: Hepp, A. A., Smith, E. J. L.
Date: 2009, 1906
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofidealdryp00hepp
Thesis (B.S.)--Armour Institute of Technology

Title: Using Controlled Unsteady Fluid Mass Addition to Enhance Jet Mixing
Creator: Raman, G.
Date: 1997-04
Publisher: American Inst Aeronaut Astronaut
Description: A rectangular jet was excited by controlled unsteady fluid mass addition using two miniature fluidic jets placed on either side of its narrow...
Show moreA rectangular jet was excited by controlled unsteady fluid mass addition using two miniature fluidic jets placed on either side of its narrow dimension. The subharmonic of the primary's preferred jet column frequency [St(D-e) = fD(e)/U-J = 0.15] was forced in the antisymmetric mode because such forcing persists for longer downstream distances than the fundamental. Details of the phase-averaged flowfield, velocity gradient terms, velocity spectra, and the mean and fluctuating flowfields were documented. The fluidically excited mode grew and persisted in the flow beyond the potential core region. Unsteady fluid mass addition of 12% (4% momentum addition) per fluidic jet resulted in a 35% reduction of the potential core length and about a 60% increase in the normalized mass flux (percentages are with reference to the primary unforced jet). On the basis of the results, it appears that fluidic devices have the potential for use in shear flow control applications.
Show less

Title: COMPRESSIVE SENSING AND RECONSTRUCTION : THEORY AND APPLICATIONS
Creator: Krishnamurthy, Ritvik Nadig
Date: 2014, 2014-07
Description: Conventional approach in acquisition and reconstruction of images from frequency domain strictly follow the Nyquist sampling theorem. The...
Show moreConventional approach in acquisition and reconstruction of images from frequency domain strictly follow the Nyquist sampling theorem. The principle states that the sampling frequency required for complete reconstruction of a signal is at least twice the maximum frequency of the original signal. This dissertation studies an emerging theory called Compressive Sensing or Compressive Sampling which goes against the conventional wisdom. Theoretically, it is possible to reconstruct images or signals accurately from a number of samples which is far smaller than the Nyquist samples. Compressive Sensing has proven to have farther implications than merely reducing sampling frequency of the signal. Possibility of new data acquisition methods from analog domain to digital form using fewer sensors, image acquisition using much smaller sensors array, to name a few. This novel theory combines sampling and compression methods thereby reducing the data acquisition resources, such as number of sensors, storage memory for collected samples and maximum operating frequency. This dissertation presents some insights into reconstruction of grey scale images and audio signals using OMP and CoSaMP algorithms. It also delves into some of the key mathematical insights underlying this new theory and explains some of the interactions between Compressive Sensing and related elds such as statistics, coding theory and theoretical computer science. viii
M.S. in Computer Engineering, July 2014
Show less

Title: LOG ANALYSIS FOR RELIABILITY MANAGEMENT IN LARGE-SCALE SYSTEMS
Creator: Zheng, Ziming
Date: 2012-07-16, 2012-07
Description: With the increasing scale and complexity of high performance computing (HPC) systems, reliability management is becoming a major concern....
Show moreWith the increasing scale and complexity of high performance computing (HPC) systems, reliability management is becoming a major concern. System logs are the primary source of information to understand and analyze system problems. Nevertheless, manual log processing is time-consuming, error-prone, and not scalable. Currently little study has been done on automated log analysis for practical use in HPC systems. In this thesis, we present a log analysis infrastructure by exploiting data mining and machine learning technologies. Our work can be broadly divided into four parts: log pre-processing, online failure prediction, automatic root cause diagnosis, and reliability modeling. We evaluate our results by means of system logs collected from production HPC systems. This work can greatly improve our understanding of faults and failures arising from hardware/software components and their interactions. It can further facilitate the reliability management for HPC systems.
Ph.D. in Computer Science, July 2012
Show less

Title: NONLINEAR PREDICTIVE CONTROL OF PERIODICALLY FORCED CHEMICAL REACTORS
Creator: Ozgulsen, F., Kendra, S. J., Cinar, A.
Date: 1993-04
Publisher: AMER INST CHEMICAL ENGINEERS
Description: A nonlinear model-predictive control strategy is developed to maintain the superior-to-steady-state performance of a periodically forced...
Show moreA nonlinear model-predictive control strategy is developed to maintain the superior-to-steady-state performance of a periodically forced chemical reactor. The performance of the predictive con troller is investigated in the presence of measurement disturbances and parametric uncertainty. It is also shown that statistically inferred input-output models can be a substitute whenever detailed fundamental models are not available. A nonlinear autoregressive polynomial model based on observed plant data is built and incorporated into the control scheme. The catalytic oxidation of ethylene in a periodically-forced, continuous stirred-tank reactor is considered as the test case.
Endnote format citation
Show less

Title: APPLICATION OF SPECTRUM OBSERVATORY MEASUREMENTS TO SUPPORT TRAFFIC MODEL-BASED DYNAMIC SPECTRUM ACCESS
Creator: Taher, Tanim Mohammed
Date: 2014, 2014-07
Description: In a 2012 report, the President’s Council of Advisors in Science and Technology (PCAST) published a memorandum that calls for the...
Show moreIn a 2012 report, the President’s Council of Advisors in Science and Technology (PCAST) published a memorandum that calls for the identification of 1000 MHz of Federal Spectrum to be shared with private (commercial) users. This dissertation proposes a system that employs RF measurements for spectrum usage modeling and Dynamic Spectrum Access (DSA) methodologies that utilize the modeling information to permit sharing of wireless resources. A procedure called the Comprehensive Band Modeling (CBM) procedure is developed that automatically models measured RF data from any band of interest and identifies the locations of signals and holes present in the band. The output of the CBM procedure is summarized in a compact versatile format that makes DSA applications feasible. The research primarily focuses on the 450-474 MHz land mobile radio (LMR) band, and several additional bands like the TV band and the 2.5-2.7 GHz band. However, the research methodology and techniques are broadly applicable to many more frequency ranges. The research has four main areas: (a) spectrum sensor design and measurements, (b) occupancy modeling, (c) communicating the modeling information in a compact form to secondary users to support DSA algorithms and protocols, and (d) tools and metrics for spectrum sharing favorability analysis. Three spectrum sensor platforms were employed in measurements – (1) a spectrum analyzer based Spectrum Observatory (SO) that was developed earlier, (2) a specially purposed software-defined radio (SDR) for measuring LMR channels, (3) and a high-speed and portable SO system based on a sensor called the RFeye. An SO continually measures RF data in a band at a high temporal resolution such that the channel switching activity is seen – like, transmitters turning on and off. Spectrum measurements of the individual RF channels in the 450-474 MHz LMR band and the two commercial bands are used to generate statistical traffic and occupancy models. Long-term measurement data is used to assess how stationary the channel is, and how often the model parameters need to be updated. The spectrum observatory supports a network of Secondary Users (SU) by communicating the traffic model parameters in a compact format to the SUs. The SUs share Primary User (PU) channels via DSA techniques. The DSA algorithms take advantage of the model parameters provided by the SO to maximize SU throughput with limited interference on the PU. The DSA coexistence techniques are evaluated via simulation. The simulation results including Spectrum Opportunity Accessed (SOA), SU throughput, and collision rates are then analyzed to provide an assessment of DSA-based spectrum sharing in that band. The main contribution of this dissertation is the aforementioned CBM procedure. The white spaces in the frequency and time domains, that is, the underutilized spectrum opportunities available for possible secondary use via DSA are automatically identified, as well as the frequency locations that are not conducive to DSA due to the presence of frequent primary licensee transmissions. In CBM, white spaces are referred to as ‘Holes’, and the licensed primary transmission frequencies as ‘Signals’. Useful information about the duty cycles and traffic patterns of incumbent users’ activity within possible secondary use channels is extracted and modeled. The model enables prospective secondary users of white spaces to predict the expected level of interference in any channel, which allows for channel ranking and optimal selection of DSA transmission parameters. The CBM model is describable by a tiered structure, where the first tier identifies the holes and signals; the second tier ranks the holes in terms of available bandwidth and incumbent duty cycle; and the third tier models the infrequent incumbent transmissions. With the three tiers of information, an SU can readily identify all the suitable DSA channels within the entire spectrum band. This essential summary information is retrieved as a “Hole Descriptor Object” (HDO) that is both compact and tractable. Empirical spectrum measurement data obtained from the three different SO platforms is used to test the performance of the CBM procedure in the 2500-2700 MHz frequency range that currently has WiMAX deployments, the TV white space band, and the 450-474 MHz LMR band in Chicago. Spectrum measurement data runs into hundreds of megabytes or gigabytes. As such, the raw information is not very applicable in practical wireless networks. The HDO objects on the other hand are compact and only kilobytes in size. The HDO objects contain all the useful and applicable information necessary for any smart radio (primary or secondary) to select transmission parameters like frequency of operation and bandwidth, so that it can efficiently operate. Thus, the advantage of the CBM procedure is that it summarizes gigabytes of raw spectrum measurements in a usable compact format that can be directly used by practical smart radios to operate using DSA paradigms. Another advantage of CBM is that it is comprehensive and automatically identifies all holes and signals. The research findings are of interest and value to a variety of Federal and Commercial entities. The models and relevant model parameters for public safety radio in the LMR band have been provided on request to the Public Safety and Homeland Security Bureau of the Federal Communications Commission (FCC). The DSA feasibility analysis methodology is of great national economic interest based on the contents of the PCAST report. The PCAST report recommends finding 1000 MHz of federal frequencies to be allocated for shared commercial and federal use. However, the technology for doing so and identifying the suitable bands requires measurements of actual spectrum usage, modeling the occupancy and existing traffic activity, and assessing DSA feasibility – these are important research aspects, and all of which are addressed in this dissertation. The results are of crucial importance to policy makers like the FCC and NTIA who will ultimately make the spectrum allocations decisions. A future network of commercial DSA SU radios operating in a shared band is likely to need access to a system to obtain live information about PU activity to optimally operate in the band with high throughput and low interference. The overall system, based on the CBM procedure and HDO objects, proposed in this thesis describes a framework for providing this information as a service to DSA networks, and hence the work is also of practical relevance to radio system designers.
Ph.D. in Electrical Engineering, July 2014
Show less

Title: PSYCHOLOGICAL WELL-BEING AND ONLINE MINDFULNESS TRAINING
Creator: Stickney, Laurie
Date: 2013-04-15, 2013-05
Description: Despite the improvements in resources and communication in today’s world, many people still do not have access to mental health resources....
Show moreDespite the improvements in resources and communication in today’s world, many people still do not have access to mental health resources. Mindfulness, a type of meditation, has been shown to be effective at reducing stress, reducing pain, and increasing general mental well-being. Mindfulness has the potential to reach many people though internet-based interventions. However, more research is needed to determine whether mindfulness retains its efficacy when delivered over the internet. Participants engaged in a six week program of internet-based mindfulness interventions. Facets of mental well-being were assessed at various time points including mood state, anxiety, quality of life, mindfulness, and psychological inflexibility. Hierarchical Linear Modeling demonstrated that over time, participants significantly increased their level of mindfulness and decreased in their psychological inflexibility. Measurements pertaining to mood, anxiety, quality of life, and perceived stress did not change significantly. Nonetheless, results from the present study suggest the potential efficacy of internet-based mindfulness interventions and highlight the need for future research in this domain.
M.S. in Psychology, May 2013
Show less

Title: Study of electric rates and ratemaking
Creator: Barrer, Glen A, Shaffer, Sydney
Date: 2009, 1915
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofelectricr00barr
Thesis (B.S.)--Armour Institute of Technology, 1915 Bibliography: leaves 43-47 B.S. in...
Show morehttp://www.archive.org/details/studyofelectricr00barr
Thesis (B.S.)--Armour Institute of Technology, 1915 Bibliography: leaves 43-47 B.S. in Electrical Engineering, 1915
Show less

Title: Minimum-bias angular and trigger-associated correlations from 200 GeV p-p collisions: jets, flows, centrality, and the underlying event, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
Creator: Prindle, D.
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: The mechanisms leading to the hadronic final state of high-energy proton-proton collisions remain an unresolved issue at the RHIC and LHC. A...
Show moreThe mechanisms leading to the hadronic final state of high-energy proton-proton collisions remain an unresolved issue at the RHIC and LHC. A substantial contribution to the hadronic final state from minimum-bias (MB) jets is dominated by non-perturbative processes and may provide the common base for any high-energy dijet. Observation of a same-side (on azimuth)“ridge” in LHC p-p collisions suggests to some that hydrodynamic flows may play a role in that small system at higher energies. The issue of p-p centrality vs triggered jets has emerged in the context of gluon trans- verse distributions in the proton inferred from DIS data. Attempts have been made to isolate and study the underlying event (UE) complementary to triggered dijets, and it is suggested that multiple parton interactions may contribute to the UE. Reference [1] considered theoretical and experimental results for UE systematics and p-p centrality in the context of a two-component (soft+hard) model derived from single-particle pt spectrum nch systematics. The study concluded that there may be a substantial contribution to the UE from the triggered dijet and that p-p centrality is not controlled significantly by a jet trigger condition (if p-p centrality is relevant at all). Further study of two-particle correlations in p-p collisions was called for, particularly the nch dependence of MB correlations. We report a comprehensive study of MB (no pt cuts) angular correlations and trigger-associated (TA) yt correlations (transverse rapidity yt = ln[(mt + pt)/mπ]) from 200 GeV p-p collisions. Angular correlations are characterized by 2D model fits that accurately distinguish among proton dissociation structure (soft), jet-related structure (hard) and a nonjet azimuth quadrupole. All angular correlations are simply represented by a (2+1)-component model. The hard and quadrupole component scale simply with the soft-component multiplicity ns, clarifying the role of centrality and the eikonal model in p-p collisions. 2D TA correlations project to a marginal 1D trigger spectrum that can be simply predicted from pt spec- trum nch dependence. 2D TA distributions can then be processed to reveal MB jet fragment (hard component) systematics comparable to measured fragmentation functions. Hard-component azimuth dependence relative to the trigger relates to UE studies. From TA analysis we can establish the kinematic limits of jet fragment production in p-p collisions.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
Show less

Title: LASER MICROMACHINING, SINTERING, AND LASER-INDUCED PLASMA DEBURRING
Creator: Gao, Yibo
Date: 2013, 2013-12
Description: Lasers can provide non-mechanical-contact, localized and concentrated energy input to materials with controlled durations and high spatial...
Show moreLasers can provide non-mechanical-contact, localized and concentrated energy input to materials with controlled durations and high spatial resolutions down to a few microns or less. Therefore, lasers have more and more applications in manufacturing and materials processing, such as laser micromachining (which is to create micro-scale features through laser-induced material removal) and laser sintering. Despite the previous research work in the literature, many laser-based manufacturing and materials processing areas still require lots of further research work. Specifically, the following topics will be investigated in the research work in this thesis: nanosecond-pulsed laser ablation of silicon carbide at an infrared wavelength, nanosecond laser-induced plasma deburring, two-step nanosecond laser surface texturing, and the fabrication of carbon nanotube (CNT)-ceramic composites through the laser sintering process.
PH.D in Mechanical and Aerospace Engineering, December 2013
Show less

repository.iit

Search the repository

Pages

Pages

Enabled Filters

Refine Results

Type

Date

Academic status of creator

Department

Subject

Creator

Part of