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- Title
- ENHANCED DEGRADATION AND PEPTIDE SPECIFICITY OF MMP-SENSITIVE SCAFFOLDS FOR NEOVASCULARIZATION OF ENGINEERED TISSUES
- Creator
- Sokic, Sonja
- Date
- 2013, 2013-07
- Description
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Biomaterial strategies for engineering tissues of clinically relevant size require the formation of rapid and stable neovascularization. The...
Show moreBiomaterial strategies for engineering tissues of clinically relevant size require the formation of rapid and stable neovascularization. The ability of an engineered scaffold to induce vascularization is highly dependent on its rate of degradation. During the process of material degradation, the scaffold should degrade in a manner allowing for cellular infiltration, lumen formation, and extracellular matrix (ECM) synthesis. Matrix metalloproteinases (MMPs) play a key role in mediating cell-induced proteolytic matrix degradation, remodeling, and controlled neovascularization. Poly (ethylene glycol) PEG hydrogels have been extensively investigated as scaffolds for tissue engineering applications due to their ease of chemical modification allowing for the recapitulation of key aspects of the neovascularization process. The goal of the work described in this thesis was to develop strategies to enhance and control the degradation of MMP-sensitive PEG diacrylate (PEGDA) hydrogels without inducing changes to the bulk physical and mechanical properties of the material and to further study the effect of the cleavage site concentration and MMP-sensitive peptide substrate specificity on the rate of neovascularization and tissue remodeling in vitro and in vivo. In the first part of this study, a detailed investigation was completed to investigate the effects of the mechanical and physical properties of the scaffolds as well as the role of proteolytically mediated hydrogel degradation on 3D fibroblast invasion within MMPsensitive PEGDA hydrogels. Initial studies focused on the use of a modified version of a previously published multistep conjugation method to generate degradable PEGDA macromer conjugates containing variations in the number of MMP-sensitive domains. Theoretical and experimental characterization of this multistep conjugation demonstrated xi that this method leads to the formation of multiple species that directly affect the compressive modulus and degradation rate of the scaffold making it difficult to control degradation independent of alterations in the bulk physical and mechanical hydrogel properties. After manipulation of multiple polymerization conditions, hydrogels with similar compressive moduli but different hydrogel degradation rates were synthesized. These initial studies showed that an increase in the incorporation of proteolytically sensitive domains in PEGDA hydrogels of similar modulus lead to enhanced degradation and 3D fibroblast invasion. In this study, the role of soluble FGF-1 on fibroblast invasion within these scaffolds was investigated and it was demonstrated that the inclusion of FGF-1 in the scaffolds results in further enhancement of fibroblast invasion in a dosedependent fashion. Further studies were necessary to develop a more controllable and robust approach in tuning scaffold degradation independent of alterations in the bulk physical and mechanical properties. In order to address this, a novel approach was developed to engineer protease-sensitive peptides with multiple proteolytic cleavage sites that could be covalently crosslinked into hydrogels without compromising the physical and mechanical biomaterial properties. This approach avoided the need for utilizing a multistep conjugation process as peptides could be incorporated into the backbone of PEG using a single step conjugation. Using this approach, hydrogels formed with the engineered peptides led to significantly enhanced degradation and neovascularization in vitro as compared to scaffolds with a single protease sensitive peptide between crosslinks. In addition, hydrogels with enhanced susceptibility to degradation promoted vascularization over a wider range of matrix properties. This approach allowed for controlled xii concentration of the proteolytic cleavage sites within the matrix and thus tuning of hydrogel degradation for tissue engineering applications. In the final study, MMP-sensitive peptide substrates specific to degradation by MMPs known to be expressed during neovascularization were screened for degradation and their role in neovascularization. MMP-sensitive PEGDA hydrogels (SSite and TriSite) were synthesized with peptide substrates sensitive to cleavage by MMP-2, MMP- 9, MMP-14, a mixed sequence of MMP-2, 9 and 14, and compared to the peptide substrate used in the previous studies, which is degraded by collagenase enzymes. The hydrogels were evaluated for their sensitivity and specificity to degradation by MMPs, in terms of cleavage site concentration, and for their role in neovascularization and tissue remodeling in vitro and in vivo. The presented approach allows for the incorporation of varying cleavage site concentration and MMP-sensitive peptide substrates into PEG hydrogels without alterations in the mechanical and physical properties of the hydrogels. Results showed that without the incorporation of growth factors in this scaffold, vascularization and tissue invasion was supported in all MMP-sensitive hydrogel groups regardless of the MMP-sensitive peptide substrate embedded in the matrix. In addition, the cleavage site concentration had a profound impact in enhancing vascularization in vitro and tissue invasion in vivo. These techniques can be used to tune the properties of polymer scaffolds for neovascularization and tissue remodeling. In addition, these studies provide insight into the effect of the physical, mechanical, and degradative properties of these systems and on the role of cleavage site concentration, and MMP substrate specificity on xiii neovascularization and tissue invasion within proteolytically degradable PEG hydrogel constructs.
PH.D in Biomedical Engineering, July 2013
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- Title
- Alleviating Homelessness in Chicago
- Creator
- Degroff, Justin
- Date
- 2011, 2011-05
- Description
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Alleviating homelessness in Chicago through the creation of a network of self-sufficient, revenue generating support nodes.
- Title
- JET MIXING CONTROL USING EXCITATION FROM MINIATURE OSCILLATING JETS
- Creator
- Raman, G, Cornelius, D
- Date
- 1995-02
- Publisher
- AMER INST AERONAUT ASTRONAUT
- Title
- PSECMAC Intelligent Insulin Schedule for Diabetic Blood Glucose Management Under Nonmeal Announcement
- Creator
- Teddy, S. D., Quek, C., Lai, E. M.-k., Cinar, A.
- Date
- 2010-03
- Publisher
- IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
- Description
-
Therapeutically, the closed-loop blood glucose-insulin regulation paradigm via a controllable insulin pump offers a potential solution to the...
Show moreTherapeutically, the closed-loop blood glucose-insulin regulation paradigm via a controllable insulin pump offers a potential solution to the management of diabetes. However, the development of such a closed-loop regulatory system to date has been hampered by two main issues: 1) the limited knowledge on the complex human physiological process of glucose-insulin metabolism that prevents a precise modeling of the biological blood glucose control loop; and 2) the vast metabolic biodiversity of the diabetic population due to varying exogneous and endogenous disturbances such as food intake, exercise, stress, and hormonal factors, etc. In addition, current attempts of closed-loop glucose regulatory techniques generally require some form of prior meal announcement and this constitutes a severe limitation to the applicability of such systems. In this paper, we present a novel intelligent insulin schedule based on the pseudo self-evolving cerebellar model articulation controller (PSECMAC) associative learning memory model that emulates the healthy human insulin response to food ingestion. The proposed PSECMAC intelligent insulin schedule requires no prior meal announcement and delivers the necessary insulin dosage based only on the observed blood glucose fluctuations. Using a simulated healthy subject, the proposed PSECMAC insulin schedule is demonstrated to be able to accurately capture the complex human glucose-insulin dynamics and robustly addresses the intraperson metabolic variability. Subsequently, the PSECMAC intelligent insulin schedule is employed on a group of type-1 diabetic patients to regulate their impaired blood glucose levels. Preliminary simulation results are highly encouraging. The work reported in this paper represents a major paradigm shift in the management of diabetes where patient compliance is poor and the need for prior meal announcement under current treatment regimes poses a significant challenge to an active lifestyle.
Endnote format citation for DOI:10.1109/TNN.2009.2036726
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- Title
- Digital Urban Park
- Creator
- Thornton, Alastair
- Date
- 5/4/2011, 2011-05
- Description
-
This project is a park that utilizes social networks and interactivity to convey and make physical the internet. This is explored through...
Show moreThis project is a park that utilizes social networks and interactivity to convey and make physical the internet. This is explored through three parts and varying levels of group interaction between both the users of the space and by the spaces direct influence from the internet.
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- Title
- HIGH PERFORMANCE, HIGH STABILITY AND LOW POWER SRAM DESIGN BY USING CARBON NANOTUBE FIELD EFFECT TRANSISTORS
- Creator
- Wang, Wei
- Date
- 2012-07-07, 2012-07
- Description
-
As the feature size of silicon semiconductor devices scales down to nanometer range, planar bulk CMOS design and fabrication encounter...
Show moreAs the feature size of silicon semiconductor devices scales down to nanometer range, planar bulk CMOS design and fabrication encounter significant challenges. This situation is exacerbated when it comes to SRAM, as SRAM takes a large part of power consumption and area overhead in modern VLSI processor designs. To achieve higher performance, stability and lower power consumption, carbon nanotube (CNT) has been introduced to SRAM design as an alternative material. The semiconducting single-walled CNTs are promising candidates for the channel material of CMOS devices because of two advantages over the other semiconductor materials: high ON current, leading to high speed and low OFF current, leading to less leakage power. In this research work, characterizing work of technology parameters for 6T carbon nanotube field effect transistor (CNFET) SRAM cell is performed for basic understanding of the relationship between SRAM delay/power and CNFET technology parameters. Stability issue is studied by investigating the diameter and transistor ratio impacts on the SRAM static noise margin (SNM). A stability-optimized 6T CNFET SRAM cell achieves 38.88% reading delay reduction, 21.61% writing delay reduction, 85.65% reading power reduction, 5.88% writing power reduction, 97.80% leakage power reduction, 41.41% SNM increment, 91.23% reading power-delay product (PDP) reduction and 26.23% writing PDP reduction, compared with conventional silicon MOSFET SRAM cell. To mitigate major CNT imperfection impacts on CNFET circuits, a misalignment immune SRAM design method is proposed to eliminate CNT misalignment problem by using etching region defined in circuit layout; and a diameter variation sensing and compensating system is designed to mitigate the negative impacts of CNT diameter variation on SRAM delay and power consumption. A hybrid silicon/CNT 4T SRAM cell design is proposed for low-power high-density cache application, which is better than conventionally used 6T SRAM in terms of power consumption and circuit area. Finally, a design flow of high performance, high stability and low power SRAM is summarized.
Ph.D. in Electrical Engineering, July 2012
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- Title
- Center for Interdisciplinary Education: tA_Final Book
- Creator
- Alvarez, Tomas
- Date
- 4/20/2011, 2011-05
- Description
-
This project consists of developing an efficient collegiate building in which the disciplines of Business, Mathematics, and Science can...
Show moreThis project consists of developing an efficient collegiate building in which the disciplines of Business, Mathematics, and Science can interact, collaborate, and ultimately create new knowledge by merging existing information. "All disciplines have imported aspects of other fields to clarify their own disciplinary perspectives."
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- Title
- Sustainable Theme Park and Museum
- Creator
- Fujishima, Kenta
- Date
- 5/4/2011, 2011-05
- Description
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An indoor facility consisting of both theme park and museum components with the integration of green and sustainable elements.
- Title
- CONTROLLER DESIGN AND DISTRIBUTED CONTROL WITHIN MULTI-AGENT SYSTEMS
- Creator
- Shao, Quan Min
- Date
- 2013, 2013-12
- Description
-
None
PH.D in Chemical and Biological Engineering, December 2013
- Title
- Screech Tones from Rectangular Jets with Spanwise Oblique Shock-cell Structures
- Creator
- Raman, G.
- Date
- 1997-01-10
- Publisher
- Cambridge Univ Press
- Description
-
Understanding screech is especially important for the design of advanced aircraft because screech can cause sonic fatigue failure of aircraft...
Show moreUnderstanding screech is especially important for the design of advanced aircraft because screech can cause sonic fatigue failure of aircraft structures. Although the connection between shock-cell spacing and screech frequency is well understood, the relation between non-uniformities in the shock-cell structures and the resulting amplitude, mode, and steadiness of screech have remained unexplored. This paper addresses the above issues by intentionally producing spanwise (larger nozzle dimension) variations in the shock-cell structures and studying the resulting spanwise screech mode. The spanwise-oblique shock-cell structures were produced using imperfectly expanded convergent-divergent rectangular nozzles (aspect ratio = 5) with non-uniform exit geometries. Three geometries were studied: (a) a nozzle with a spanwise uniform edge, (b) a nozzle with a spanwise oblique (single-bevelled) edge, and (c) a nozzle that had two spanwise oblique (double-bevelled) cuts to form an arrowhead-shaped nozzle. For all nozzles considered, the screech mode was antisymmetric in the transverse (smaller nozzle dimension) direction allowing focus on changes in the spanwise direction. Three types of spanwise modes were observed: symmetric (I), antisymmetric (II), and oblique (III), The following significant results emerged: (i) for all cases the screech mode corresponds with the spanwise shock-cell structure, (ii) when multiple screech modes are present, the technique presented here makes it possible to distinguish between coexisting and mutually exclusive modes, (iii) the strength of shocks 3 and 4 influences the screech source amplitude and determines whether screech is unsteady. The results presented here offer hope for a better understanding of screech and for tailoring shock-containing jets to minimize fatigue failure of aircraft components.
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- Title
- VIBRATIONAL CONTROL OF AN EXOTHERMIC CSTR - PRODUCTIVITY IMPROVEMENT BY MULTIPLE INPUT OSCILLATIONS
- Creator
- Shu, X. S., Rigopoulos, K., Cinar, A.
- Date
- 1989-02
- Publisher
- IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
- Description
-
A. Cinar et al. (1987) have shown that vibrational control of an exothermic continuous stirred tank reactor (CSTR) by vibrating the total flow...
Show moreA. Cinar et al. (1987) have shown that vibrational control of an exothermic continuous stirred tank reactor (CSTR) by vibrating the total flow rate modifies its behavior and leads to stabilized operation in its unstable steady-state region. Here, the effect of multiple vibrating inputs and the contribution of their phase shift are investigated. Theoretical and experimental results indicate productivity improvement and amplitude reduction in reactor temperature swings by vibrating both input flow rate and input concentrations.
Endnote format citation
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- Title
- Chicago Intermodal Commuter Transit Development: Strailman_Chris_MastersProject_2011
- Creator
- Strailman, Chris
- Date
- 4/27/2011, 2011-05
- Description
-
This project focuses on the connectivity of different forms of transit and different neighborhoods in Chicago. Starting at the scale of city...
Show moreThis project focuses on the connectivity of different forms of transit and different neighborhoods in Chicago. Starting at the scale of city wide transit systems, it narrows down to a specific node and deals with the design and planning of a transit oriented development.
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- Title
- Multi- Generational Housing in China: Mixed-use Multi- Generational Housing in China Final Poster
- Creator
- Liu, Ling
- Date
- 2011-05, 2011-05
- Description
-
In China, too much population causes early retire age, one child policy, extremely high housing pressure, too little land for open space,...
Show moreIn China, too much population causes early retire age, one child policy, extremely high housing pressure, too little land for open space, little or no public facilities. Also, it causes the lost of many long tradition. The losing of multi- generational living is just one of them. This project is a humanistic response to the social problems.
Sponsorship: Denison, Dirk
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- Title
- Automated control of high temperature short time pasteurization
- Creator
- Negiz, A., Cinar, A., Schlesser, J. E., Ramanauskas, P., Armstrong, D. J., Stroup, W.
- Date
- 1996-12
- Publisher
- ELSEVIER SCI LTD
- Description
-
Cascade and multivariable control of a high temperature shot? time (HTST) pasteurization system were tested and compared with the performance...
Show moreCascade and multivariable control of a high temperature shot? time (HTST) pasteurization system were tested and compared with the performance of single-loop feedback control. Multivariable control was implemented on the basis of computations of product temperatures that yield equivalent lethality at a residence time of 15 s at 161 degrees F in the holding tube. Both cascade and multivariable controllers reduced product temperature fluctuations and overshoot compared to single-loop feedback control. Multivariable control was based on on-line computation of equivalent total lethality and it permitted operation at variable flow rates or at the most desirable temperatures for product quality and functionality. Copyright (C) 1996 Elsevier Science Ltd.
Endnote format citation
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- Title
- Polarised Drell-Yan physics at COMPASS, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
- Creator
- Franco, Celso
- Date
- 2013-09-15, 2013-09-15
- Publisher
- IIT Press
- Description
-
The COMPASS experiment at CERN is one of the leading experiments studying the spin structure of the nucleon. Until now, the Parton...
Show moreThe COMPASS experiment at CERN is one of the leading experiments studying the spin structure of the nucleon. Until now, the Parton Distribution Functions (PDFs) and the Transverse Momentum Dependent Parton Distribution Functions (TMD PDFs) of protons and deuterons have been studied in Semi-Inclusive Deep Inelastic Scattering (SIDIS) measurements. The polarised Drell-Yan (DY) process is a complementary way to access the TMD PDFs, as it allows us to measure convolutions of only PDFs without involving fragmentation functions (FFs). COMPASS aims to perform the first ever polarised DY experiment in the world, which is foreseen to start in late 2014. By detecting dimuons from DY events we will be able to extract azimuthal spin asymmetries, each containing a convolution of two TMD PDFs, one from a negative pion beam with a momentum of 190 GeV/c and the other one from a transversely polarised proton target (NH₃). After their disentangling we can access four of the eight TMD PDFs needed to describe the nucleon structure at leading twist, like the Sivers and the Boer-Mulders functions. The opportunity to study, in the same experiment, the TMD PDFs from both SIDIS and DY processes is unique at COMPASS. Therefore, we are in privileged conditions to confirm or to deny the expected sign change in Sivers and Boer-Mulders functions when accessed via DY or SIDIS processes. An overview of the preparation and future measurements of the polarised DY experiment will be provided.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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- Title
- POLYMER ELECTROLYTE MEMBRANES FOR ELECTROCHEMICAL ENERGY CONVERSION AND STORAGE SYSTEMS: FUEL CELLS AND REDOX FLOW BATTERIES
- Creator
- Yun, Sukhwan
- Date
- 2014, 2014-12
- Description
-
Direct methanol fuel cells (DMFCs) and redox flow batteries (RFBs) are well-known electrochemical energy conversion/storage systems that...
Show moreDirect methanol fuel cells (DMFCs) and redox flow batteries (RFBs) are well-known electrochemical energy conversion/storage systems that utilize redox reactions to convert or store electricity. Ion exchange membranes (IEMs) are used in DMFCs and RFBs as electrolyte separators. The critical requirements for IEMs in these applications are high ionic conductivity, low electrolyte permeability, high stability, and low cost. Silsesquioxane (SQO)-based sulfonated poly(etheretherketone) composite membranes were synthesized. Morphological changes in the composite membranes resulting from the introduction of SQO were studied using small-angle x-ray scattering. A sharp decrease in proton conductivity with SQO loading (> 20 wt%) was attributed to morphological changes in the membrane, including agglomeration and inhomogeneous dispersion of SQO particles within the ionic domains. Anion exchange membranes (AEMs) based on quaternized cardo-poly(etherketone) (QPEK-C) were prepared and evaluated for all-vanadium RFB (VRFB) applications. The QPEK-C AEMs with different degrees of functionalization (0.9–1.6) exhibited sulfate ion conductivities ranging between 5.6 and 15.2 mS cm-1 at 30 oC. The AEM had a lower VO2+ permeability (2.8×10-8 cm2 s-), compared to that of Nafion® 212 (2.9±0.2 ×10-7 cm2 s-1), which was attributed to the Donnan exclusion effect. The mechanical strength of QPEK-C AEM degraded by 35% after exposure to a 1.5 M VO2+ solution for 1500 hours due to the oxidation of aromatic rings. A single-cell VRFB employing the AEM separator yielded current and energy efficiencies (at 30 mA cm-2) of 97-99% and 80-82 %, respectively. Enhanced sulfate ion conductivity (8.4 ± 0.2 mS cm-1) and decreased VO2+ permeability (0.53×10-9 cm2 s-1) were achieved by incorporating 20 wt% of n-(trimethoxysilylpropyl)-n,n,n-trimethylammonium additives into QPEK-C, (the pristine QPEK-C AEM yielded corresponding values of 4.5 ± 0.5 mS cm-1 and 1.09×10-9 cm2 s-1). About 99% coulombic efficiency was achieved with the VRFBs employing the composite AEM. However, a rapid reduction of the ionic conductivity down to the value of the pristine membrane was observed when the composite AEM was immersed in 1.5 M VO2+ solution for 3 days. Vanadium-cerium RFBs (V-Ce RFBs) evaluated with QPEK-C AEM separators yielded identical energy efficiency (84%) to corresponding RFBs evaluated with Nafion® 212. However, after over 20 charge-discharge cycles, the V-Ce RFB with the AEM separator yielded unchanged efficiency and capacity, while a 50% loss of capacity was observed with the Nafion® separator. This suggested that QPEK-C AEMs are promising candidates for RFB separators when different cations are used in the two electrolyte solutions, in that they act as efficient barriers that preclude the intermixing of the cations due to the Donnan exclusion effect.
Ph.D. in Chemical Engineering, December 2014
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- Title
- Adaptive Reuse Hybrid Development: AdaptiveReuseHybridDevelopment_Poster_SP11
- Creator
- Jarzabkowski, Henry
- Date
- 5/4/2011, 2011-05
- Description
-
Producing and designing a prototype hybrid use development strategy for a neighboring pair of preexisting historical building in Chicago’s...
Show moreProducing and designing a prototype hybrid use development strategy for a neighboring pair of preexisting historical building in Chicago’s North side community of Lakeview.
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- Title
- waterWORKS
- Creator
- Webster, Reed
- Date
- 5/3/2011, 2011-05
- Description
-
Water shortages will be a global problem by the year 2025. With the Great Lakes Basin accounting for 95% of the fresh water in the United...
Show moreWater shortages will be a global problem by the year 2025. With the Great Lakes Basin accounting for 95% of the fresh water in the United States it will soon become our most valuable natural resource. In re-defining urban relationships to the Great Lakes a healthy, ecologically stable, and regenerative water system can become our greatest national asset. Providing a prototype solution for one of these urban areas (Traverse City, MI) may set a precedent for long term protection of the Great Lakes.
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- Title
- FORCED PERIODIC OPERATION OF TUBULAR REACTORS
- Creator
- Ozgulsen, F., Cinar, A.
- Date
- 1994-10
- Publisher
- PERGAMON-ELSEVIER SCIENCE LTD
- Description
-
Forced periodic operation of tubular reactors can increase conversion and yield if proper operating conditions and forcing policies are...
Show moreForced periodic operation of tubular reactors can increase conversion and yield if proper operating conditions and forcing policies are selected. A numerical approach is proposed for computing the effects of periodic input forcing by a shooting algorithm. Such computational tools permit the assessment of the benefits of forced periodic operation of a specific reactor system and the identification of the ranges of operating conditions where forced periodic operation is beneficial. This information provides valuable insight for planning detailed experimental studies. Determining the influential input variables and bracketing the ranges of the operating conditions for improving reactor performance will reduce significantly the experiments needed for selecting the most favorable reactor operation policies. The application of the numerical algorithm is illustrated by assessing the benefits of forced periodic operation to a CO oxidation reactor model. The results reveal substantial improvement in performance with slow cycling in feed concentration.
Endnote format citation
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- Title
- Oil Rig Eco Hotel: OilRigEcoHotel_Presentation
- Creator
- Marcan, Stephanie
- Date
- 2011, 2011-05
- Description
-
By refashioning the design and programmatic use of an offshore oil rig into a luxury hotel for ecotourists, a new age of responsible travel...
Show moreBy refashioning the design and programmatic use of an offshore oil rig into a luxury hotel for ecotourists, a new age of responsible travel may emerge. By twisting the symbol of oil dependency into an ecologically preserved, environmentally accountable and revenue-producing prototype, the ideals of reuse, energy and environment can be viewed through a new lens. This design creates interesting and innovative living spaces and environments aided by sustainable integrations to create a “living machine” that establishes connections between all building systems as well as inhabitant inputs and outputs resulting in an energy independent habitat.
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