Investigating Cost-Effective and Time-Efficient Ways to Speed Up Transit

With the emphasis on cities worldwide prioritizing more environmentally friendly forms of transportation, along with a new focus on equity to ensure that underserved and disadvantaged communities are served equitably and receive services that enable economic opportunity, access to recreation opportunities, and social services, equitable and sustainable forms of transportation are required. This study explores potential methods for enhancing and strengthening transit as a reliable and sustainable means of transportation. This study evaluates cost-effective methods for achieving significant gains in improving transit reliability and speed

Control Law Calculation and Verification Methods for the Variable Stability Navion In-Flight Simulation Aircraft

The University of Tennessee Space Institute’s (UTSI) variable stability research aircraft, Ryan Navion N66UT, was extensively modified by the Princeton University in the 1960’s. When UTSI acquired the aircraft from Princeton, volumes of calibration data, charts, and schematics manuals were transferred to UTSI. Based on the study and research of available Princeton documents, methods of calculating flight control laws were “reverse-engineered”. The Variable Stability Navion employs an implicit model following structure to achieve in-flight simulation of other aircraft’s flying quality. Mathematical formulas were derived to calculate stability derivative potentiometer settings, for the analog response feedback flight controls system. MATLAB scripts were created to generate potentiometer settings, for both longitudinal and lateral-directional in-flight simulations, and Simulink models were used to verify the results. This report outlines the calculation and verification process to allow the Variable Stability Navion to simulate different aircraft’s stability and dynamic responses. Sample calculations are focused on the in-flight simulation of the Twin Otter. This report also serves as a step-by-step guide for deriving desired flight control laws

Development and validation of an instrument to measure Chinese post-secondary and part-time students’ motivation to learn accounting in Hong Kong

In the current research, we developed and validated a questionnaire to measure Chinese working adults’ motivation to study accounting on a path of lifelong learning in Hong Kong, China. We conducted individual in-depth interviews with adult learners (n = 30) and professionals (n = 12) in study 1 and study 2. Qualitative analysis showed six specific common themes for Chinese working adults’ motivation to learn accounting. Based on these results and the research literature, we developed a list of 31 provisional items for the questionnaire. In Study 3, we administered the provisional questionnaire to students (N = 426) from sub-degree, undergraduate, and graduate programs. These data were analyzed using quantitative analysis. Exploratory factor analysis showed a sixdimensional structure. Removal of redundant items resulted in a 17-item questionnaire. Confirmatory factor analysis provided evidence of the reliability and validity of this measure, which assesses six domains of adult learners’ motivations for pursuing continuing education in accounting: development of knowledge and skills; family cohesion; reinforcement of social networking and communication; career development; enrichment of life; and self-development. This measure in the Chinese cultural context can be used for research purposes and for assessing students’ motivation in accounting programs in Hong Kong

Inducible and Selective Erasure of Memories in the Mouse Brain via Chemical-Genetic Manipulation

SummaryRapid and selective erasures of certain types of memories in the brain would be desirable under certain clinical circumstances. By employing an inducible and reversible chemical-genetic technique, we find that transient αCaMKII overexpression at the time of recall impairs the retrieval of both newly formed one-hour object recognition memory and fear memories, as well as 1-month-old fear memories. Systematic analyses suggest that excessive αCaMKII activity-induced recall deficits are not caused by disrupting the retrieval access to the stored information but are, rather, due to the active erasure of the stored memories. Further experiments show that the recall-induced erasure of fear memories is highly restricted to the memory being retrieved while leaving other memories intact. Therefore, our study reveals a molecular genetic paradigm through which a given memory, such as new or old fear memory, can be rapidly and specifically erased in a controlled and inducible manner in the brain

In-situ strain tuning of the Dirac surface states in Bi2Se3 films

Elastic strain has the potential for a controlled manipulation of the band gap and spin-polarized Dirac states of topological materials, which can lead to pseudo-magnetic-field effects, helical flat bands and topological phase transitions. However, practical realization of these exotic phenomena is challenging and yet to be achieved. Here, we show that the Dirac surface states of the topological insulator Bi2Se3 can be reversibly tuned by an externally applied elastic strain. Performing in-situ x-ray diffraction and in-situ angle-resolved photoemission spectroscopy measurements during tensile testing of epitaxial Bi2Se3 films bonded onto a flexible substrate, we demonstrate elastic strains of up to 2.1% and quantify the resulting reversible changes in the topological surface state. Our study establishes the functional relationship between the lattice and electronic structures of Bi2Se3 and, more generally, demonstrates a new route toward momentum-resolved mapping of strain-induced band structure changes

Racial Differences in Preventive and Complementary Health Behaviors and Attitudes

Screening tests have been developed for many diseases—the presence of cancer, especially—but are differentially utilized among racial/ethnic groups. In addition to standard medical screening techniques, some patients opt to use Complementary and Alternative Medicine (CAM) for prevention and treatment. The purpose of the current study is to examine racial/ethnic disparities in primary and secondary preventive health behaviors, determine differences in use of complementary and alternative health regimens, and determine which health attitudes and health self-management factors are associated with use of complementary alternative medicine. If differences among ethnic/racial groups in perceived health status, preventive health care behaviors, and use of CAM can be more fully understood, then health professionals will be able to better tailor health promotion interventions and integrate these factors

Component Segmentation of Engineering Drawings Using Graph Convolutional Networks

We present a data-driven framework to automate the vectorization and machine interpretation of 2D engineering part drawings. In industrial settings, most manufacturing engineers still rely on manual reads to identify the topological and manufacturing requirements from drawings submitted by designers. The interpretation process is laborious and time-consuming, which severely inhibits the efficiency of part quotation and manufacturing tasks. While recent advances in image-based computer vision methods have demonstrated great potential in interpreting natural images through semantic segmentation approaches, the application of such methods in parsing engineering technical drawings into semantically accurate components remains a significant challenge. The severe pixel sparsity in engineering drawings also restricts the effective featurization of image-based data-driven methods. To overcome these challenges, we propose a deep learning based framework that predicts the semantic type of each vectorized component. Taking a raster image as input, we vectorize all components through thinning, stroke tracing, and cubic bezier fitting. Then a graph of such components is generated based on the connectivity between the components. Finally, a graph convolutional neural network is trained on this graph data to identify the semantic type of each component. We test our framework in the context of semantic segmentation of text, dimension and, contour components in engineering drawings. Results show that our method yields the best performance compared to recent image, and graph-based segmentation methods.Comment: Preprint accepted to Computers in Industr

Tree management and the greening of the environment in Hong Kong : a study of collaborative governance

published_or_final_versionPolitics and Public AdministrationMasterMaster of Public Administratio

Analysis of operational parameters, reactor kinetics, and floc characterization for the removal of estrogens via electrocoagulation

Estrogenic compounds can cause human and ecological health issues and have been detected in surface and drinking water. In this research a reactor analysis determined the impact of operational parameters, the best fit kinetic model for the removal of estrone (E1), 17β-estradiol (E2), estriol (E3), and 17α-ethynylestradiol (EE2) using a bench-top iron electrocoagulation reactor, and characterized the floc generated in-situ. The parameters investigated were current density, conductivity, stir rate, and polarity reversal. Estrogen removal correlated well with an increase in current density, while conductivity did not impact removal but did reduce potentials. High stir rates and frequent polarity reversal demonstrated greater removal. The operating parameters that achieved the greatest estrogen removal were a current density of 16.7 mA cm−2, conductivity of 1000 μS cm−1, stir rate of 500 rpm, and a polarity reversal time of 30 s. These parameters led to average removal efficiencies of 81%, 87%, 85%, and 97% for E1, E2, E3, and EE2, respectively. The removal data for all estrogenic compounds best fit a pseudo-first order relationship with kinetic rate constants of 0.015 min−1 for E1 and E2, 0.016 min−1 for E3 and 0.040 min−1 for EE2. The floc formed in-situ were characterized by determining the crystalline phases with X-ray diffraction, the size and zeta potential, and the shape and major components using scanning electron microscope with energy-dispersive X-ray spectrometer. The iron coagulant generated during electrocoagulation was lepidocrocite with a point of zero charge of 5.67 and an average floc diameter of 2255 nm