Definitional Extension in Type Theory

When we extend a type system, the relation between the original system and its extension is an important issue we want to know. Conservative extension is a traditional relation we study with. But in some cases, like coercive subtyping, it is not strong enough to capture all the properties, more powerful relation between the systems is required. We bring the idea definitional extension from mathematical logic into type theory. In this paper, we study the notion of definitional extension for type theories and explicate its use, both informally and formally, in the context of coercive subtyping

BEYOND HELPING: Beyond Helping: A Cross-National Investigation of Psychological Distance in Cause-Related Product Buying Decisions

Cause-related marketing (CRM) has become popular in recent years, where corporate giving for a cause is tied to consumers’ purchase of the firm’s products. The prior research has mainly focused on how consumers perceive cause-company relationship e.g. cause fit) and consumers’ pro-social characteristics (e.g. altruism) in influencing CRM effectiveness. Additionally, more studies have been called to focus on emerging market’s cause-related product (CRP) buying. In an attempt to address these research gaps, this thesis examines CRP buying by bring the consumers’ self-cause relation into focus, adopting psychological distance as a theoretical framework in order to offer a deeper understanding of the psychology of buying decisions in CRM. A mixed method approached was applied. Study One conducted in-depth interviews to explore the psychological distance in CRM context. Using a cross-national sample from China (225) and the UK (220), Study Two conducted a scenario-based survey to examine the role of psychological distance in CRP buying in different country contexts. Overall, the findings demonstrate all four dimensions of psychological distance affect CRP buying, among which consumers’ perceived temporal distance and uncertainty toward social causes have the most influential impact. The perceived closeness’ positive influence on CRP buying could be enhanced by consumers’ favourable perceptions towards CRM and their pro-social characteristics. It also shows that products with an accumulative nature and a relatively large donation magnitude should be tied with psychologically closer social cause. Significant differences are found among consumers’ CRP buying in developed and emerging markets: 1. Unlike UK consumers, Chinese consumers are not affected by their perceived social and physical distance towards social causes. 2. Chinese consumers are not in favour of providing extra effort in participating a CRM campaign other than buying a CRP whereas UK consumers may be willing to actively involve in devoting time and effort in CRM campaign. 3. UK consumers tend to buy more CRPs linked with high donation magnitude than Chinese consumers. Theoretical and practical contributions are given

Spatiotemporal modeling of air pollutants and their health effects in the Pittsburgh region

Air pollutants have been associated with adverse health outcomes such as cardiovascular and respiratory diseases through epidemiological studies. Spatiotemporal and spatial statistics are widely used in both exposure assessment and health risk estimation of air pollutants. In the current paper, spatiotemporal and spatial models are developed for and applied to four specfic topics about air pollutants: (1) estimating spatiotemporal variations of particulate matter with diameter less than 2.5 um (PM2.5) using monitoring data and satellite aerosol optical depth (AOD) measurements, (2) estimating long-term spatial variations of ozone (O3) using monitoring data and satellite O3 profile measurements, (3) spatiotemporal associating acute exposure of air pollutants to mortality, and (4) spatiotemporal associating chronic air pollution exposure to lung cancer incidence. Environmental, socioeconomic and health data from Allegheny county and the State of Pennsylvania are collected to illustrate these techniques. The public health significance of these studies includes characterizing the exposure level of air pollutants and their health risks for mortality caused by cardiovascular and respiratory diseases and lung cancer incidence in the Pittsburgh region and developing novel spatiotemporal models such as spatiotemporal generalized estimating equations for the regression analysis of spatiotemporal counts data, especially for the massive spatiotemporal data used in epidemiological studies

Unparticle Physics Effects on D0-anti-D0 Mixing

The mixing of $K^0-\bar{K^0}$, $D^0-\bar{D^0}$ and $B_{(s)}^0-\bar{B^0_{(s)}}$ provides a sensitive probe to explore new physics beyond the Standard Model. The scale invariant unparticle physics recently proposed by Georgi can induce flavor-changing neutral current and contribute to the mixing at tree level. We investigate the unparticle effects on $B^0-\bar{B^0}$ and $D^0-\bar{D^0}$ mixing. Especially, the newly observed $D^0-\bar{D^0}$ mixing sets the most stringent constraints on the coupling of the unparticle to quarks.Comment: 9 pages, some errors corrected, published versio

Detecting fractional Josephson effect through 4π4\pi phase slip

Fractional Josephson effect is a unique character of Majorana Fermions in topological superconductor system. This effect is very difficult to detect experimentally because of the disturbance of quasiparticle poisoning and unwanted couplings in the superconductor. Here, we propose a scheme to probe fractional DC Josephson effect of semiconductor nanowire-based topological Josephson junction through 4{\pi} phase slip. By exploiting a topological RF SQUID system we find that the dominant contribution for Josephson coupling comes from the interaction of Majorana Fermions, resulting the resonant tunneling with 4{\pi} phase slip. Our calculations with experimentally reachable parameters show that the time scale for detecting the phase slip is two orders of magnitude shorter than the poisoning time of nonequilibrium quasiparticles. Additionally, with a reasonable nanowire length the 4{\pi} phase slip could overwhelm the topological trivial 2{\pi} phase slip. Our work is meaningful for exploring the effect of modest quantum fluctuations of the phase of the superconductor on the topological system, and provide a new method for quantum information processing.Comment: 5 pages, 3 figure

Detecting fractional Josephson effect through 4π4\pi phase slip

Fractional Josephson effect is a unique character of Majorana Fermions in topological superconductor system. This effect is very difficult to detect experimentally because of the disturbance of quasiparticle poisoning and unwanted couplings in the superconductor. Here, we propose a scheme to probe fractional DC Josephson effect of semiconductor nanowire-based topological Josephson junction through 4{\pi} phase slip. By exploiting a topological RF SQUID system we find that the dominant contribution for Josephson coupling comes from the interaction of Majorana Fermions, resulting the resonant tunneling with 4{\pi} phase slip. Our calculations with experimentally reachable parameters show that the time scale for detecting the phase slip is two orders of magnitude shorter than the poisoning time of nonequilibrium quasiparticles. Additionally, with a reasonable nanowire length the 4{\pi} phase slip could overwhelm the topological trivial 2{\pi} phase slip. Our work is meaningful for exploring the effect of modest quantum fluctuations of the phase of the superconductor on the topological system, and provide a new method for quantum information processing.Comment: 5 pages, 3 figure