Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1982. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / by Kevin LeRoy Johnson. / M.S.

The goal of this thesis is to develop a test platform for measuring surface effect ship (SES) response to wave loads. The platform is designed and built incorporating a self-propelled vehicle with data acquisition and navigation capabilities. Theoretical analysis is performed, various hardware and electronic parts are designed and built and software applications developed. Wave tank experiments are conducted for test platform evaluation and determination of vehicle response to a range of wave conditions. Furthermore, a three-dimensional model of the AIRCAT scale model SES is created. The theoretical analysis shows that the scale effects in some cases are great, so resonance phenomena cannot be observed. The experimental results clearly show that the heave, pitch and aircushion excess pressure fluctuations increase as the air-blower input level increases. The bow skirt arrangement needs improvements and further experimentation is necessary in order to draw conclusions about the wave loads applied on the skirt. / by Nicholas Kouvaras. / Thesis (M.S.C.S.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.

Selective laser sintering (SLS) is a rapid prototyping method in which three-dimensional objects are constructed by sintering thin layers of a variety of powdered materials via laser beam. In SLS, as in most other Rapid Prototyping methods, the produced parts exhibit varying degrees of intrinsic porosity due to the discrete nature of layer-by-layer production. Selective scanning and discrete bonding of individual particles or clusters of particles impart local porosity, which is mostly an undesired trait as the part integrity decreases with increased porosity. However, there are a number of emerging or potential applications as in tissue engineering and composite/functionally graded materials, in which part porosity and its control during production are needed. In this study, the manufacturing capabilities of selective laser sintering are investigated towards producing predesigned porous structures using a polymeric powder. The porous structures are characterized in two main categories: regular porous structures, which involve geometries such as predesigned holes and lattice structures that have orderly porous architecture, and irregular porous structures, which exhibit random pore architecture that is intrinsic in all SLS parts. The limitations of producing regular porous structures are investigated, identified and quantified, based on hole size and dimensional accuracy. An experimental analysis based on design of experiments is employed to investigate the effects of processing parameters on the resulting macroscopic pore properties of irregular porous structures. A mathematical relation is developed to quantify and predict the relations between the SLS process parameters: Laser power, hatching distance, laser scan spacing, and the resulting apparent mass density (as a measure of porosity). The subsequent tests verify accuracy of the developed empirical model.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaf 77. / by Reginald Van Lee. / M.S.

yes / Ten reinforced-concrete continuous deep beams with openings were tested to failure. The main variables investigated were the shear span-to-overall depth ratio, and the size and location of openings. Two failure modes influenced by the size and location of web openings regardless of the shear span-to-overall depth ratio were observed. The normalised load capacity of beams having a web opening area ratio of 0·025 within exterior shear spans was approximately similar to that of their companion solid beams. Continuous deep beams having web openings within interior shear spans exhibited a higher load capacity reduction with the increase of the opening size, similar to simply supported deep beams with web openings. Formulae based on the upper bound analysis of the plasticity theory were proposed to predict the load capacity of continuous deep beams with web openings. Comparisons between the measured and predicted load capacities showed a good agreement.

Yes / For composite beams with low degrees of shear connection, additional deflections occur due to slip in the shear connectors, which can be significant for beams with low degrees of shear connection. A design formula is presented for the effective stiffness of composite beams taking account of the stiffness of the shear connectors, which is compared to measured deflections of 6 symmetric beams and an 11m span composite beam of asymmetric profile. It is shown that the comparison is good when using a shear connector stiffness of 70 kN/mm for single shear connectors and 100 kN/mm for pairs of shear connectors per deck rib. Results of push tests on a range of deck profiles confirm these initial elastic stiffnesses. To ensure that the slip at the serviceability limit state does not lead to permanent deformations of the beam, it is proposed that the minimum degree of shear connection should not fall below 30% for un-propped beams and 40% for propped beams of symmetric cross-section. / European Commission

yes / The behaviour of seismic-resistant buildings relies heavily upon the inclusion of energy dissipating devices. For concentrically-braced frames, this function is accomplished by diagonal bracing members whose performance depends upon both cross-sectional properties and global slenderness. Traditionally preferred rectangular hollow sections are susceptible to local buckling, particularly in cold-formed tubes, owing to the residual stresses from manufacture. This paper explores the response of hollow and concrete-filled circular tubes under cyclic axial loading. The uniformity of the circular cross-section provides superior structural efficiency over rectangular sections and can be further optimised by the inclusion of concrete infill. A series of experiments was conducted on filled and hollow specimens to assess the merit of the composite section. Comparisons were drawn between hot-finished and cold-formed sections to establish the influence of fabrication on member performance. Two specimen lengths were utilised to assess the influence of non-dimensional slenderness. Parameters such as ductility, energy dissipation, tensile strength and compressive resistance are presented and compared with design codes and empirically derived predictions.

Chen, Yanyan. / "Septembet 2011." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 135-148). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Research Problem and Objective --- p.2 / Chapter 1.3 --- Research Significance --- p.3 / Chapter 1.4 --- Methodology --- p.5 / Chapter 1.5 --- Organization of Thesis --- p.14 / Chapter Chapter 2 --- State Rescaling and Regional Planning: Concepts and Issues in the Western Countries and China --- p.16 / Chapter 2.1 --- Introduction --- p.16 / Chapter 2.2 --- The Reworking of State Power --- p.16 / Chapter 2.3 --- The Rescaling Concept --- p.19 / Chapter 2.4 --- "The State Rescaling Concept, Regional Development and Rescaling Process in Regions" --- p.24 / Chapter 2.5 --- The Regional Scale of Politics: Expressions of State Rescaling --- p.29 / Chapter 2.6 --- The State Restructuring and the Rise of Regions in China: A Review --- p.32 / Chapter 2.7 --- Summary --- p.36 / Chapter Chapter 3 --- Conceptualizing Spatial Planning as a Process of State rescaling: towards an Analytical Framework --- p.38 / Chapter 3.1 --- Conceptualizing the Spatial Planning as a Process of State Rescaling --- p.38 / Chapter 3.2 --- Regional Planning in China --- p.44 / Chapter 3.3 --- Towards a Theoretical Framework --- p.53 / Chapter 3.4 --- Summary --- p.58 / Chapter Chapter 4 --- The State in Transition: A Need for Planning Coordination in Cross-boundary Railways --- p.61 / Chapter 4.1 --- Changing Political Economy --- p.61 / Chapter 4.2 --- Institutional Structure in Planning Regional Railways --- p.71 / Chapter 4.3 --- Pearl River Delta: the Railway Planning Context --- p.82 / Chapter 4.4 --- General Propositions on Planning Coordination of Regional Railways in China --- p.86 / Chapter Chapter 5 --- Planning the Pearl River Delta Intercity Railway: Institutional Form and the Planning Mechanisms --- p.90 / Chapter 5.1 --- Introduction --- p.90 / Chapter 5.2 --- Planning the PRD Intercity Railway: an Introduction of Three Planning Phases --- p.90 / Chapter 5.3 --- The Planning Process of the PRD Intercity Railway: Interaction among Multiple Jurisdictions --- p.96 / Chapter 5.4 --- The Scalar Changes of Central-provincial-local State: State Rescaling Process --- p.122 / Chapter Chapter 6 --- Conclusion --- p.128 / Chapter 6.1 --- Major Findings --- p.128 / Chapter 6.2 --- Suggestions for Further Studies --- p.133

A 6-Degree Of Freedom (DOF) numeric model and computer simulation along with the 1/10th scale physical model of the Rapidly Deployable Stable Platform (RDSP) are being developed at Florida Atlantic University in response to military needs for ocean platforms with improved sea keeping characteristics. The RDSP is a self deployable spar platform with two distinct modes of operation enabling long distance transit and superior seakeeping. The focus of this research is the development of a Dynamic Position (DP) and motion mitigation system for the RDSP. This will be accomplished though the validation of the mathematical simulation, development of a novel propulsion system, and implementation of a PID controller. The result of this research is an assessment of the response characteristics of the RDSP that quantifies the performance of the propulsion system coupled with active control providing a solid basis for further controller development and operational testing. / by Sean P. Marikle. / Thesis (M.S.C.S.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.

As humans explore greater depths of Earth’s oceans, there is a growing need for the installation of subsea structures. 71% of the earth’s surface is ocean but there are limitations inherent in current detection instruments for marine applications leading to the need for the development of underwater platforms that allow research of deeper subsea areas. Several underwater platforms including Autonomous Underwater Vehicles (AUVs), Remote Operated Vehicles (ROVs), and wave gliders enable more efficient deployment of marine structures. Deployable structures are able to be compacted and transported via AUV to their destination then morph into their final form upon arrival. They are a lightweight, compact solution. The wrapped package includes the deployable structure, underwater pump, and other necessary instruments, and the entire package is able to meet the payload capability requirements. Upon inflation, these structures can morph into final shapes that are a hundred times larger than their original volume, which extends the detection range and also provides long-term observation capabilities. This dissertation reviews underwater platforms, underwater acoustics, imaging sensors, and inflatable structure applications then proposes potential applications for the inflatable structures. Based on the proposed applications, a conceptual design of an underwater tubular structure is developed and initial prototypes are built for the study of the mechanics of inflatable tubes. Numerical approaches for the inflation process and bending loading are developed to predict the inflatable tubular behavior during the structure’s morphing process and under different loading conditions. The material properties are defined based on tensile tests. The numerical results are compared with and verified by experimental data. The methods used in this research provide a solution for underwater inflatable structure design and analysis. Several ocean morphing structures are proposed based on the inflatable tube analysis. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection