Phase-matching of multiple-cavity detectors for dark matter axion search

Conventional axion dark matter search experiments employ cylindrical microwave cavities immersed in a solenoidal magnetic field. Exploring higher frequency regions requires smaller size cavities as the TM010 resonant frequencies scale inversely with cavity radius. One intuitive way to make efficient use of a given magnet volume, and thereby to increase the experimental sensitivity, is to bundle multiple cavities together and combine their individual outputs ensuring phase-matching of the coherent axion signal. We perform an extensive study for realistic design of a phase-matching mechanism for multiple-cavity systems and demonstrate its experimental feasibility using a double-cavity system.Comment: 5 pages, 2 figures, 1 tabl

Accelerated identification of equilibrium structures of multicomponent inorganic crystals using machine learning potentials

The discovery of new multicomponent inorganic compounds can provide direct solutions to many scientific and engineering challenges, yet the vast size of the uncharted material space dwarfs current synthesis throughput. While the computational crystal structure prediction is expected to mitigate this frustration, the NP-hardness and steep costs of density functional theory (DFT) calculations prohibit material exploration at scale. Herein, we introduce SPINNER, a highly efficient and reliable structure-prediction framework based on exhaustive random searches and evolutionary algorithms, which is completely free from empiricism. Empowered by accurate neural network potentials, the program can navigate the configuration space faster than DFT by more than 10$^{2}$-fold. In blind tests on 60 ternary compositions diversely selected from the experimental database, SPINNER successfully identifies experimental (or theoretically more stable) phases for ~80% of materials within 5000 generations, entailing up to half a million structure evaluations for each composition. When benchmarked against previous data mining or DFT-based evolutionary predictions, SPINNER identifies more stable phases in the majority of cases. By developing a reliable and fast structure-prediction framework, this work opens the door to large-scale, unbounded computational exploration of undiscovered inorganic crystals.Comment: 3 figure

The Effects of Phonetic Duration on Loanword Adaptation: Mandarin Falling Diphthong in Chinese Korean

This study examines how Mandarin falling sonority diphthongs are adapted to a Chinese Korean dialect. It investigates how the subtle phonetic conditions of the source language affect adaptation, and if and how those phonetic effects differ in established loanwords compared to the on-line adaptation of novel loan forms. We found that in this bilingual population, while the Mandarin diphthongs are usually adapted as monophthongs, obeying the native phonological restriction against falling diphthongs, the retention of the input diphthongs in violation of the native constraint is also quite common. Additionally, we found that the choice of the monophthong vs. diphthong realization is strongly affected by the input phonetic duration and in particular, the durational difference among the different tones is robustly reflected in the adaptation patterns.The authors would like to thank three anonymous reviewers for their suggestions that improved the paper. We would also like to thank Professor Sun Ying at Liaoning University, Professor Yunyan Luo at Beijing Foreign Studies University, and Yuanyang Song for their invaluable help during the data collection process, Sung-Geol Kim for help with stimulus preparation, Hyoung-Seok Kwon for help with data analysis, Professor Oh Sung-Ae at the Ocean University of China and the audience members at LabPhon15 and the Workshop on the Phonetics and Phonology in Loanword Adaptation for comments on earlier versions of the paper. The work was supported by the Insight Grant from the Social Science and Humanities Research Council of Canada

Numerical modelling of the microwave heating behaviour of lunar regolith

The field of In Situ Resource Utilisation (ISRU) is expanding rapidly with a particular focus on developing ISRU technologies and applications to support a longer-term surface exploration of the Moon. In this respect, microwave sintering is proposed to be one of the potential fabrication methods for developing a 3D printing technique for construction processes on the Moon. Thus, understanding the behaviour of lunar regolith, available at different locations on the Moon (e.g. mare versus highlands regions), under microwave heating is crucial for developing an optimal method for microwave sintering. As the availability of real lunar regolith on Earth is highly limited, developing an appropriate numerical model of microwave heating behaviour of lunar regolith is urgently required. In this paper, three representative lunar regolith samples (selected from the database of Apollo sample collections) with pre-defined material properties have been simulated under seven input powers and three specimen sizes. This paper discusses the outcomes of these simulations and the potential contribution of the model for developing a desired 3D printing technique utilising microwave sintering of lunar regolith

Understanding the Role of Electronic Effects in CO on the Pt-Sn Alloy Surface via Band Structure Measurements

Using angle-resolved photoemission spectroscopy, we show direct evidence for charge transfer between adsorbed molecules and metal substrates, i.e., chemisorption of CO on Pt(111) and Pt-Sn/Pt(111) 2 x 2 surfaces. The observed band structures show a unique signature of charge transfer as CO atoms are adsorbed, revealing the roles of specific orbital characters participating in the chemisorption process. As the coverage of CO increases, the degree of charge transfer between CO and Pt shows a clear difference to that of Pt-Sn. With comparison to density functional theory calculation results, the observed distinct features in the band structure are interpreted as back-donation bonding states formed between the Pt molecular orbital and the 2 pi orbital of CO. Furthermore, the change in the surface charge concentration, measured from the Fermi surface area, shows that the Pt surface has a larger charge concentration change than the Pt-Sn surface upon CO adsorption. The differences between Pt and Pt-Sn surfaces are due to the effect of Pt-Sn intermetallic bonding on the interaction of CO with the surface

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Colonizing the Port City Pusan in Korea: a study of the process of Japanese domination in the urban space of Pusan during the open-port period (1876-1910)

This dissertation aims to analyze the transformation of Pusan by examining the social, political, economic, and cultural changes during the open-port period (1876-1910). Prior to annexation, Pusan, as the first open port in Korea, reflected features of the colonial urban development in which alien power achieved and sustained a hegemonic domination on socio-cultural-economic dimensions of people’s lives.Colonial history in Korea has been divided and moving on parallel lines. The ‘nationalist school’ and the ‘socioeconomic school’ have failed to come together and move us into a deeper understanding of the Japanese colonial period. In order to narrow the gap between the two schools of thought, this thesis suggests looking at ‘colonial modernity’ through the analytical lens of the colonial city of Pusan. The approach examines changes in the social, economic, and cultural life of people rather than through the traditional binary construction of ‘victim versus victimizer’ or ‘colonial repression versus national resistance.’In particular, I pay close attention to the fact that colonization is a process of imperial expansion by means of colonialists. In the end, the process of colonization in Pusan was a process by which the Japanese settlers expanded in wealth, population, influence, and power. The cluster of factors – enlargement of settlement (living space), the expansion of the economy (economic opportunity), improvement of public enterprises, such as transportation infrastructure, water supply and hygiene (improving quality of life) – were catalysts for the Japanese settlers to take up residence in Pusan. Based on the transformation of the urban space of Pusan at this micro level, I discuss a hierarchy of power relations within the spatial boundary of Pusan. In other words, I focus on human aspects of these changes rather than on systemic changes. I attempt to demonstrate how studying a city can offer a useful category of analysis for the question of ‘modernity’ in Korea.</p

Colonizing the port city Pusan in Korea : a study of the process of Japanese domination in the urban space of Pusan during the open-port period (1876-1910)

This dissertation aims to analyze the transformation of Pusan by examining the social, political, economic, and cultural changes during the open-port period (1876-1910). Prior to annexation, Pusan, as the first open port in Korea, reflected features of the colonial urban development in which alien power achieved and sustained a hegemonic domination on socio-cultural-economic dimensions of people's lives. Colonial history in Korea has been divided and moving on parallel lines. The 'nationalist school' and the 'socioeconomic school' have failed to come together and move us into a deeper understanding of the Japanese colonial period. In order to narrow the gap between the two schools of thought, this thesis suggests looking at 'colonial modernity' through the analytical lens of the colonial city of Pus an. The approach examines changes in the social, economic, and cultural life of people rather than through the traditional binary construction of 'victim versus victimizer' or 'colonial repression versus national resistance. ' In particular, I pay close attention to the fact that colonization is a process of imperial expansion by means of colonialists. In the end, the process of colonization in Pus an was a process by which the Japanese settlers expanded in wealth, population, influence, and power. The cluster of factors - enlargement of settlement (living space), the expansion of the economy ( economic opportunity), improvement of public enterprises, such as transportation infrastructure, water supply and hygiene (improving quality of life) - were catalysts for the Japanese settlers to take up residence in Pusan. Based on the transformation of the urban space of Pusan at this micro level, I discuss a hierarchy of power relations within the spatial boundary of Pusan. In other words, I focus on human aspects of these changes rather than on systemic changes. I attempt to demonstrate how studying a city can offer a useful category of analysis for the question of 'modernity' in Korea.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Modeling Relationships Between the Use of English as a Second Language Learning Strategies and the Test Performance of Asian Students

149 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1999.The present study found only weak relationships between language learning strategies and language proficiency. Only 13% and 15% of variance of the listening and grammar/reading factor were explained by the language teaming strategies. The model for the relationships among the metacognitive, cognitive, and language proficiency factors appeared not to vary across the different proficient level groups. The social and affective strategies were found not to be included in the model for the high level group.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD