List Edge Colorings of Planar Graphs with 7-cycles Containing at Most Two Chords

In this paper we prove that if G is a planar graph, and each 7-cycle contains at most two chords, then G is edge-k-choosable, where k = max{8, ?(G) + 1}

The effect of compact development on travel behavior, energy consumption and GHG emissions in Phoenix metropolitan area

Suburban growth in the U.S. urban regions has been defined by large subdivisions of single-family detached units. This growth is made possible by the mobility supported by automobiles and an extensive highway network. These dispersed and highly automobile-dependent developments have generated a large body of work examining the socioeconomic and environmental impacts of suburban growth on cities. The particular debate that this study addresses is whether suburban residents are more energy intensive in their travel behavior than central city residents. If indeed suburban residents have needs that are not satisfied by the amenities around them, they may be traveling farther to access such services. However, if suburbs are becoming like cities with a wide range of services and amenities, travel might be contained and no different from the travel behavior of residents in central areas. This paper will compare the effects of long term suburban growth on travel behavior, energy consumption, and GHG emissions through a case study of neighborhoods in central Phoenix and the city of Gilbert, both in the Phoenix metropolitan region. Motorized travel patterns in these study areas will be generated using 2001 and 2009 National Household Travel Survey (NHTS) data by developing a four-step transportation demand model in TransCAD. Energy consumption and GHG emissions, including both Carbon Dioxide (CO₂) and Nitrous Oxide (N₂O) for each study area will be estimated based on the corresponding trip distribution results. The final normalized outcomes will not only be compared spatially between Phoenix and Gilbert within the same year, but also temporally between years 2001 and 2009 to determine how the differential land use changes in those places influenced travel. The results from this study reveal that suburban growth does have an impact on people's travel behaviors. As suburbs grew and diversified, the difference in travel behavior between people living in suburban and urban areas became smaller. In the case of shopping trips the average length of trips for suburban residents in 2009 was slightly shorter than that for central city residents. This convergence was substantially due to the faster growth in trip lengths for central city compared to suburban residents in the 8-year period. However, suburban residents continue to be more energy intensive in their travel behavior, as the effect of reduction in trip length is likely to be offset by the more intensive growth in trip frequency. Additionally, overall energy consumption has grown significantly in both study areas over the period of study.MSCommittee Chair: Guhathakurta, Subhrajit ; Committee Member: French, Steven; Committee Member: Xu, Yanzh

Infrastructure REITs Empower “New Infrastructure” during the COVID-19 Pandemic: A Chinese Case Study

In 2020, the COVID-19 pandemic accelerated the development of new infrastructure in China. Thus, the term “new infrastructure” appeared for the first time and frequently in official documents at the national level, having become a kind of prescription for China’s move away from policies focused on controlling the disease towards those that promote the resumption of economic growth. The financing of this new infrastructure depends on innovative financial instruments, namely real estate investment trusts (REITs). The focus in this article is on the ways in which REITs make new infrastructure possible using as a case study the country’s first domestic REIT designed for the purpose, the China United Fund-Zheshang Asset Management, Shanghai-Hangzhou, Huizhou- Hangzhou Expressway Asset Support Special Plan, which was successfully issued on the Shanghai Stock Exchange on September 24, 2019. The analysis presented here indicates that infrastructure REITs have laid much of the foundation for economic growth in China and provides a basis for some suggestions for making the most of this financial instrument

Probing Ring Resonator Sensor Based on Vernier Effect

The Vernier effect has seen extensive application in optical structures, serving to augment the free spectral range (FSR). A substantial FSR is vital in a myriad of applications including multiplexers, enabling a broad, clear band comparable to the C-band to accommodate a maximum number of channels. Nevertheless, a large FSR often conflicts with bending loss, as it necessitates a smaller resonator radius, thus increase the insertion loss in the bending portion. To facilitate FSR expansion without amplifying bending loss, we employed cascaded and parallel racetrack resonators and ring resonators of varying radius that demonstrate the Vernier effect. In this study, we designed, fabricated, and tested multiple types of racetrack resonators to validate the Vernier effect and its FSR extension capabilities. Our investigations substantiate that the Vernier effect, based on cascaded and series-coupled micro-ring resonator (MRR) sensors, can efficiently mitigate intra-channel cross-talk at higher data rates. This is achieved by providing larger input-to-through suppression, thus paving the way for future applications

Weight Bank Addition Photonic Accelerator for Artificial Intelligence

Neural networks powered by artificial intelligence play a pivotal role in current estimation and classification applications due to the escalating computational demands of evolving deep learning systems. The hindrances posed by existing computational limitations threaten to impede the further progression of these neural networks. In response to these issues, we propose neuromorphic networks founded on photonics that offer superior processing speed than electronic counterparts, thereby enhancing support for real time, three dimensional, and virtual reality applications. The weight bank, an integral component of these networks has a direct bearing on their overall performance. Our study demonstrates the implementation of a weight bank utilizing parallelly cascaded micro ring resonators. We present our observations on neuromorphic networks based on silicon on insulators, where cascaded MRRs play a crucial role in mitigating interchannel and intrachannel cross talk, a persistent issue in wavelength division multiplexing systems. Additionally, we design a standard silicon photonic accelerator to perform weight addition. Optimized to offer increased speed and reduced energy consumption, this photonic accelerator ensures comparable processing power to electronic devices