The study proposes an application of Talens (2003) methodological framework for assessing neighbourhood-level (i.e., non-motorised mode) accessibility, and offers recommendations for improving non-motorized transportation (NMT) accessibility to enhance multimodal integration between bicycles and buses in contemporary North American suburban neighbourhoods. Accessibility (or access) is defined as the average travel time or distance between a given origin and destination along the shortest available street network route. The study considers characteristics of the transportation network such as available route directness, facilities, and transit service provision to determine their impacts on bicycle access. A further methodology for comparing bicycle versus bus modal efficiencies within suburban contexts is developed and applied to the case study. A review of approaches designed to promote bicycling while discouraging personal automobile use provides a toolbox of proven treatments that are applied to a case study of Saskatoon, Saskatchewan a city of approximately 200,000 people. The approach provides a process that can be used by city or transit planners to identify neighbourhoods that lack sufficient access and apply treatments that improve bicycle accessibility and bicycle-transit integration. Results suggest existing potential for the bicycle as an access mode within contemporary suburban neighbourhood transportation networks. The case study supports the notion that suburban bicycle-bus integration could be used as a viable alternative to automobiles for daily home-to-node activity trips, and raises questions about the current allocation of public transit service to suburban routes within the context of the case study. Discussion and conclusions suggest directions for future research in this field of sustainable urban transportation planning.

Increased demand for smaller electronics is driving the electronic packaging industry to develop smaller, more efficient component level packages. Surface mounted components, such as flip chips, ball grid arrays (BGAs), and chip-scale packages (CSPs), are being developed for use in high-volume production. All of these technologies use solder bumps to attach the active silicon to the substrate, and traditional nondestructive methods such as machine vision, acoustic microscopy or x-ray inspection cannot easily find solder bump defects. Therefore, a system, consisting of an Nd:YAG laser that delivers pulses of infrared energy to the surface of the chip, a laser interferometer to record surface vibrations, and a high-speed data acquisition system to record the signals, was developed. The pulsed laser generates ultrasound on the chips surface, exciting the whole chip into a vibration motion, and the interferometer measures the vibration displacement of the chips surface at several points. Changes in the quality of the device or its attachment to the board produce changes in the free vibration response. Characterization of the differences between good devices and devices with defects, both in time domain and frequency domain, is performed using signal analysis. The system has inspected flip chips and chip scale packages for missing and misaligned solder balls, but to characterize the resolution of the system for open solder joints, a study of the vibration modes excited by the laser source in a flip chip was performed on specimens with intentionally created defects. Experimental measurements of excited modes were compared with a modal analysis model created in ANSYS, and defects were detected as small changes in the mode shape on the surface of the chips. Current inspection methods have also been inadequate for inspecting multi-layer ceramic capacitors (MLCCs). Flex cracks, caused by manufacturing processes, often cause the capacitors to fail in-service. Samples that have been cracked intentionally were compared with reference samples to determine the feasibility of using this technique to monitor the condition of MLCCs on an assembly line. Currently, there is no on-line inspection method for controlling this problem, but this technique was able to differentiate between good and damaged capacitors.

This thesis focuses on the growth of cracks which are small in relation to the material microstructure especially the situation of clusters of small cracks grown from smooth surfaces, termed micro-multi-site cracking, as is frequently the case for components in service. A proper understanding of this regime of crack growth will allow for less conservative maintenance schedules as well as the application of more sensitive health monitoring systems which are currently under development. To address the problem a significant experimental investigation of micro-multi-site cracking was conducted on 7075-T7351 aluminum alloy. Using the resulting data a micro-structurally based transition crack length is defined to determine the point which separates small and long crack growth. This definition is based upon the observed evolution of scatter in the growth rates of growing small cracks. It is shown that this scatter falls with growth until the transition point is reached where it assumes a constant value for the growth of long cracks. It is then shown that the total population of cracks within the clusters can be considered as bi-modal. One distribution consists of primary cracks which can grow and ultimately cause specimen failure. The second distribution consists of secondary cracks, the growth of which ultimately arrests. Several methods for experimentally separating the two distributions have been developed. The first method relies upon the defined transition point between small and long crack behavior. A second method based upon the second derivative of the crack length versus cycle count data has also been developed. Since the secondary cracks cannot lead to failure their data must be discarded prior to any analysis. It is then shown that failure to do so will lead to erroneous non-conservative predictions of crack growth.

Heavy-duty diesel vehicle (HDDV) operations are a major source of pollutant emissions in major metropolitan areas. Accurate estimation of heavy-duty diesel vehicle emissions is essential in air quality planning efforts because highway and non-road heavy-duty diesel emissions account for a significant fraction of the oxides of nitrogen (NOx) and particulate matter (PM) emissions inventories. Yet, major modeling deficiencies in the current MOBILE6 modeling approach for heavy-duty diesel vehicles have been widely recognized for more than ten years. While the most recent MOBILE6.2 model integrates marginal improvements to various internal conversion and correction factors, fundamental flaws inherent in the modeling approach still remain. The major effort of this research is to develop a new heavy-duty vehicle load-based modal emission rate model that overcomes some of the limitations of existing models and emission rates prediction methods. This model is part of the proposed Heavy-Duty Diesel Vehicle Modal Emission Modeling (HDDV-MEM) which was developed by Georgia Institute of Technology. HDDV-MEM first predicts second-by-second engine power demand as a function of vehicle operating conditions and then applies brake-specific emission rates to these activity predictions. To provide better estimates of microscopic level, this modeling approach is designed to predict second-by-second emissions from onroad vehicle operations. This research statistically analyzes the database provided by EPA and yields a model for prediction emissions at microscopic level based on engine power demand and driving mode. Research results will enhance the explaining ability of engine power demand on emissions and the importance of simulating engine power in real world applications. The modeling approach provides a significant improvement in HDDV emissions modeling compared to the current average speed cycle-based emissions models.

In this thesis, we demonstrated the effectiveness and the accuracy of the FD-FD method for complex optical waveguide structures such as the micro ring resonator, micro disk resonator, tapered waveguides and waveguides terminated with tilted facets. We are able to achieve the goals by deriving the following modification/extension of the original FD-FD methods. In frequency domain, we can build an accurate frequency-domain modal absorbing boundary condition (ABC) for both the homogeneous region and for the layered background. This allows us to connect the analytical modal solutions with FD solutions and thus reduce the area of the FD domain. In addition, we adopt an effective index averaging method for representing equivalent material for grid cells containing more than one kind of materials. For the TM case, for each grid cell we need to compute effective indices for all four surrounding cells (left, right, up, and down). For the TE case, we need to compute just one effective index within each grid cell. Note that we employ two different averaging schemes for the TE and the TM cases. To solve the huge block tri-diagonal matrix equation (derived from the FD-FD approximation) we modified the Thomas method and we were able to obtain the solutions of linear equations involving more than a hundred thousand variables under a few minutes. We used our method to analyze optical micro-ring waveguides, micro-disk cavities, adiabatic tapered waveguides and waveguides terminated with tilted facets. The simulated results include the reflection coefficients, transmission coefficients and field distribution.

Abstract Maritime transportation is important to national development because of Taiwan is in surrounding seas region. Therefore it is necessary that this research aimed to safety of the crane transportation system. This research investigated davit structure with a telescopic arm of a ship by means of the static analysis and modal analysis. To achieve the purpose, the researcher used the computer-aided design software Solidworks to set up this structure model. After that, he used finite element analysis software ANSYS to analyze the data. This research simulated in three situations. In static analysis, the researcher found the maximum displacement, the maximum von Mises stress and factors for safety of the structure in 16 dimensional sets in 53¢X of inclination at the davit with the telescopic arm being the shortest. After that, he discussed its tendency situation. In addition, he also checked the original structure in 53¢X of inclination at the davit with the telescopic arm being the longest and horizontal at the davit with the telescopic arm being the longest, respectively. In modal analysis, the researcher found natural frequencies and vibration shapes of the original structure. The structure had good vibration-proof ability and the resonance effect possibility not to be high. Generally, the researcher hoped that this study could provide helpful references for the relevant davit structure designers in the future.

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Adopting the generative framework (Chomsky, 1988) and the theory of argument structure (e.g. Grimshaw, 1990), the present study reexamines the Mandarin Chinese middle V-qilai constructions and argues against the previous analyses (e.g. Sung, 1994; Wang, 2005a) that V-qilai is a main predicate. First, it is proposed in the present study that the Evaluative as well as the Eventive V-qilai sentences can both be regarded as the middle constructions; that is, both [-Agent] and [+Agent] V-qilai constructions can be middle sentences. Second, comparing with Huang¡¦s (1988) analysis of the resultative constructions, it is argued in the present study that the second predicate, i.e. the modification predicate, serves as the main predicate. The present study also proposes the two different syntactic representations of the Evaluative and Eventive middle V-qilai constructions,¡@and adopts Wang (2005b) and Lin & Tang (1995) to propose that the V-qilai serves as a modal: Not only can the V-qilai predicates be classified into the raising type and the control type (cf. Wang, 2005b), but can also be classified into the Evaluative/epstemic type and the Eventive/deontic type, just as Mandarin Chinese modals (cf. Lin and Tang, 1995). Moreover, the argument structures of the modification predicates determine the syntactic representations of the V-qilai sentences: Theme-modifying predicates construe Evaluative V-qilai sentences, and Agent-modifying predicates construe Eventive V-qilai sentences. The Evaluative/epistemic middle sentences like zhe ke pingguo chi qilai hen hao chi ¡¥this apple tastes good¡¦ disallow the Agent, and the Theme NP moves from the modification clause to the matrix subject position to meet the EPP feature. Eventive/deontic middle sentences like zhe jian gongguo Zhangsan zuo qilai hen renzhen ¡¥the job, Zhangsan does it seriously¡¦, on the other hand, allow an Agent, and the Theme NP is assumed to be base-generated in situ. That is, the V-qilai in the Evaluative sentences is a raising modal, while the V-qilai in the Eventive sentences is assumed to be a control modal. The third issue concerns which types of verbs can enter into the V-qilai constructions. Similar to English middle constructions (Fagan, 1992), Chinese activity verbs and accomplishment verbs can enter into the V-qilai constructions. Lexically, qilai is unlikely to incorporate with the achievement verb complex like zhao-dao ¡¥find¡¦ or xue-hui ¡¥acquire¡¦ (cf. Sung, 1994). The semantic factor is related to the continuous or the inchoative sense of qilai; verbs with the continuous sense (activity verbs) or inchoative sense (accomplishment verbs) are more likely to enter into the V-qilai constructions.

Thesis (M.S. in Astronautical Engineering)--Naval Postgraduate School, September 1990. / Thesis Advisor(s): Agrawal, Brij N. Second Reader: Titus, Harold. "September 1990." Description based on title screen as viewed on December 17, 2009. DTIC Identifier(s): Attitude Control Systems, Flexible Structures, Spacecraft, Structural Response, Resonant Frequency, Experimental Design, Model Tests, Active Control, Gifts Computer Program, Dynamic Response, Computerized Simulation, Control Theory, Modal Analysis, Laboratory Tests, Theses. Author(s) subject terms: Attitude Control, Flexible Structures. Includes bibliographical references (p. 52). Also available in print.

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