Bus reform in Seoul, Republic of Korea

노트 : Case study prepared for Global Report on Human Settlements 201

Sit Next To Someone Different Every Day - How Public Transport Contributes To Inclusive Communities

The social aspects of creating sustainable, inclusive communities through an integrated approach to mobility, from UITP research and other sources.Institute of Transport and Logistics Studies. Faculty of Economics and Business. The University of Sydne

Characterizing the Charging Properties of Lunar Dust is Critical to Returning to the Moon

Reliable electron yield (EY) measurements of highly insulating granular particles have long been considered too difficult to collect due the many experimental complexities that arise from the nature of the granular materials. This has led to a critical knowledge gap for both engineering strategies and basic science issues essential for myriad important space applications. This talk will emphasize the preliminary EY measurements of highly insulating granular samples we have collected, including a range of sasmples with typical particle size ranging from ~1 μm to ~100 μm, samples with cubical, spherical and highly angular particle shapes, studies of highly angular Al2O3 polishing compound particles adhered to graphitic carbon conductive tape from 0% to ~100% coverage that demonstrates the effectiveness of the sample preparation methods used for dust samples [4], as well as an in depth study on surface roughness using an analysis technique called the patch model. Acquisition of these accurate high-yield curves, which showed minimal charging effects, demonstrated our ability to make EY measurements for high-yield highly-insulating samples, unlike previous results for dust which showed highly suppressed yields due to severe charging effects [1-3]. All this work has importance in applications surrounding lunar dust, which has been recognized as one of the most immediate and critical issues faced when expanding into deep space, mitigation of charged dust. The effects of surface roughness [5] were demonstrated through comparison of EY for highly polished single crystal sapphire, rougher microcrystalline Al2O3, and very rough and porous layers of granular alumina; these were found to have the same shape of the yield curves and energy at maximum yield, while maximum yield decreased as roughness increased. It was apparent that the maximum yield drastically decreased as the surface roughness of the materials increased from sample to sampl

Electron Yield Measurements of Highly Insulating Granular Samples Related to Charging of Dusty Plasmas

Reliable electron yield (EY) measurements of highly insulating granular particles have long been considered too difficult to collect due the many experimental complexities that arise from the nature of the granular materials. This has led to a critical knowledge gap for both engineering strategies and basic science issues essential for myriad important space applications. This talk will emphasize the preliminary EY measurements of highly insulting granular samples we have collected, including a range of samples with typical particle size ranging from ~1 μm to ~100 μm, samples with cubical, spherical and highly angular particle shapes, studies of highly angular Al2O3 polishing compound particles adhered to graphitic carbon conductive tape from 0% to ~100% coverage that demonstrates the effectiveness of the sample preparation methods used for dust samples. Acquisition of these accurate high-yield curves, which showed minimal charging effects, demonstrated our ability to make EY measurements for high-yield highly-insulating samples, unlike previous results for dust which showed highly suppressed yields due to severe charging effects. All this work has importance in applications surrounding lunar dust, which has been recognized as one of the most immediate and critical issues faced when expanding into deep space, mitigation of charged dust. The effects of surface roughness were demonstrated through comparison of EY for highly polished single crystal sapphire, rougher microcrystalline Al2O3, and very rough and porous layers of granular alumina; these were found to have the same shape of the yield curves and energy at maximum yield, while maximum yield decreased from 15 to ~2.5 as roughness increased. It was apparent that the maximum yield drastically decreased as the surface roughness of the materials increased from sample to sample.https://digitalcommons.usu.edu/fsrs2022/1072/thumbnail.jp

Preparation and Characterization of Highly Insulating Granular Samples for Electron Yield Measurement

This experiment focuses primarily on the preparation and characterization of granular samples for the eventual purpose of electron yield measurements. Highly insulating granular samples are notoriously difficult to prepare and present a myriad ofcomplications from both experimental and practical frameworks. A famous example of this was during the 1969 Apollo 11 mission when electrostatically adhered lunar dust damaged the equipment and astronauts suits and led to purported health effects. The electrical properties of this dust for charging and discharge is essential to preventing these effects. In this study, particles of varying size, shape, and composition are used to create multilayered samples with a wide range of particulate coverage on a substrate that can withstand vacuum conditions. The particulate samples were characterized and subsequent electron emission measurements were then compared to measurements of the bulk particulate and substrate materials. Measurements demonstrated the ability to perform these difficult measurements and how the sample properties affected yields

Solar Electron Radiation Effects on NASA Space Station Samples

The Lunar Gateway Space Station is meant to aid in the re-exploration of the moon and must be able to survive the harsh conditions in space, specifically solar electron radiation. The experiment investigated potential materials for the Gateway mission and how they withstand high energy electron bombardment meant to mimic a portion of this solar radiation. Potential material damage that can impact spacecraft performance includes charging, arc-induced blow off, and changes in color and other optical properties. The samples were exposed to a beam of high energy electrons (30 keV) for several minutes, while current and video data was recorded. The location, magnitude and timing of charging and discharge was also monitored during beam exposure using visible videos to detect cathodoluminescence and arc discharges. High resolution photos of the samples taken before and after beam exposure are used to investigate electron-beam induced changes. The resulting data indicates locations of possible damage done through certain mechanisms such as electrostatic breakdown (ESD), which can occur when voltage variance within the material exceeds the dielectric strength, creating destructive current paths within the material. The highly insulating materials tested included a complex fiberglass weave (Betacloth) and perfluoroalkoxy alkane (PFA). PFA showed the most signs of damage, especially optical discoloration. Any other small scale signs of physical damage are still being investigated. The results of this experiment will then be submitted to NASA for consideration in regards to the Gateway project. Presentation Time: Wednesday, 1-2 p.m

Preparation, Characterization and Electron Yield Analysis on Highly Insulating Granular Particles

This study focuses on obtaining reliable electron yield measurements of highly insulating granular particles of various shape, size, and composition. Measurements of this kind have long been considered too difficult to collect on granular samples due to experimental complexities leading to a critical knowledge gap in the fundamental electrostatic behaviors of dust. A significant portion of this study was spent on preparing and characterizing granular samples before any type of measurement took place. Particles of varying sizes ranging from ~1 μm to ~100 μm, shapes including cubical, spherical, and angular, and composition including NaCl, MgO, Al2O3 and LHS1, were used to create a multilayered sample with a wide range of particulate coverage on an adhesive substrate that can withstand vacuum conditions. After preparation these particulate samples were characterized via scanning electron microscopy and subsequent electron emission measurements were then compared to measurements of the bulk particulate and substrate materials. Results demonstrated the ability to perform these difficult measurements and how the varying sample properties like roughness and coverage affected yields

Teacher development and multiliteracies pedagogy: Challenges and opportunities for postsecondary language programs

Over the past two decades, postsecondary language programs have experienced a paradigm shift away from communicative approaches toward more text-based curricula and the development of students’ multiple literacies. Numerous curricular and course-level models exist, and empirical research has documented the feasibility, linguistic outcomes, and perceptions of multiliteracies approaches. Yet few studies have investigated how postsecondary language teachers learn about and implement multiliteracies pedagogy and limited professional development resources exist to support teachers in this endeavor. To respond to these gaps and to recent calls for increased research into multiliteracies pedagogy and language teacher development, this article has three aims. First, we summarize current knowledge about postsecondary language teachers’ understandings and implementation of the multiliteracies framework, beginning with the 2011 AAUSC volume and continuing to the present. Next, we identify gaps and unanswered questions in this scholarship and suggest directions for future research. Finally, we discuss professional development needs for language teachers and program directors implementing multiliteracies approaches in postsecondary language programs and suggest tools and practices that might facilitate this work

USING SATELLITE IMAGERY IN PREDICTING KANSAS FARMLAND VALUES

Can remotely sensed imagery improve hedonic land price models? A remotely sensed variable was added to a hedonic farmland value model as a proxy for land productivity. Land cover data were used to obtain urban and recreational effects as well. The urban and recreational effects were statistically significant but economically small. The remotely sensed productivity variable was statistically significant and economically large, indicating that knowing the "greenness" of the land increased the explanatory power of the hedonic price model. Thus, depending upon the cost of this information, including remotely sensed imagery in traditional hedonic land price models is economically beneficial.Land Economics/Use,

Contamination of Detained Sediment in Sustainable Urban Drainage Systems

Adsorption is a key water pollution remediation measure used to achieve stormwater quality improvement in Sustainable urban Drainage Systems (SuDS). The level of contamination of detained sediment within SuDS assets is not well documented, with published investigations limited to specific contaminant occurrence in ponds, wetlands or infiltration devices (bioretention cells) and generally focused on solute or suspended sediment. Guidance on contamination threshold levels and potential deposited sediment contamination information is not included in current UK SuDS design or maintenance guidance, primarily due to a lack of evidence and understanding. There is a need to understand possible deposited sediment contamination levels in SuDS, specifically in relation to sediment removal maintenance activities and potential impact on receiving waterways of conveyed sediment. Thus, the objective of the research presented herein was to identify what major elements and trace metals were observable in (the investigated) SuDS assets detained sediment, the concentration of these major elements and trace metals and whether they met/surpassed ecotoxicity or contaminated land thresholds. The research presented here provides evidence of investigated SuDS sediment major element and trace metal levels to help inform guidance and maintenance needs, and presents a new methodology to identify the general cause (anthropocentric land use) and extent of detained SuDS fine urban sediment contamination through use of a contamination matrix