Pattern formation of quantum jumps with Rydberg atoms

We study the nonequilibrium dynamics of quantum jumps in a one-dimensional chain of atoms. Each atom is driven on a strong transition to a short-lived state and on a weak transition to a metastable state. We choose the metastable state to be a Rydberg state so that when an atom jumps to the Rydberg state, it inhibits or enhances jumps in the neighboring atoms. This leads to rich spatiotemporal dynamics that are visible in the fluorescence of the strong transition. It also allows one to dissipatively prepare Rydberg crystals

A vapor barrier for cold testing printed circuit cards

Cold testing method prevents formation of frost on printed circuit boards and part holders during testing at sub-zero temperatures. Freon permits rapid attainment of the required testing temperature

An exploratory investigation of the cooling drag associated with general aviation propulsive systems

A systematic investigation of the drag associated with cooling air flow in contemporary general aviation engine installations is proposed. Theoretical and experimental methods include a state-of-the-art survey, determination of cooling drag by flight tests, and establishment of relative magnitude and components of cooling drag

Heat Transport in Mesoscopic Systems

Phonon heat transport in mesoscopic systems is investigated using methods analogous to the Landauer description of electrical conductance. A "universal heat conductance" expression that depends on the properties of the conducting pathway only through the mode cutoff frequencies is derived. Corrections due to reflections at the junction between the thermal body and the conducting bridge are found to be small except at very low temperatures where only the lowest few bridge modes are excited. Various non-equilibrium phonon distributions are studied: a narrow band distribution leads to clear steps in the cooling curve, analogous to the quantized resistance values in narrow wires, but a thermal distribution is too broad to show such features.Comment: To be published in Superlattices and Microstructures, special issue in honor of Rolf Landauer, March 198

Determinants of Industrial Property Rents in the Chicago Metropolitan Area

Urban economists have long understood the theoretical importance of transportation infrastructure and accessibility on the location choice of households and firms. We utilize a readily available data set of transaction rents in the Chicago metropolitan area to investigate the determinants of industrial property rents. Among the factors considered are proximity to transportation infrastructure, characteristics of the property, the term structure of lease agreements, and local attributes of the neighborhood. Empirical results suggest property, lease, and local demographics play important roles in determining rents. Despite the fact that industrial property tends to locate very close to rail lines and interstate highways, transportation infrastructure has much less influence. There is evidence that there is an upward sloping lease term structure premium and that the premium varies over time. The model is also used to develop a constant quality rent index for the Chicago commercial property market. Compared to average rents and asking rents, the estimated constant quality index shows a smaller run up in rents from 2003 through 2008 and a larger drop off in rents through the end of 2011

Sources of Cardiovascular Health Information and Channels of Health Communication Among Urban Population in Nigeria

This study employed mixed methods to investigate the preferred sources of health information and later explored the views of community healthcare workers on the enablers, barriers and ways of overcoming barriers to health communication. The study found that majority of the participants preferred their source of CV (cardiovascular) health information from the healthcare workers including the medical doctors, nurses, and pharmacists. On the other hand, the least preferred source of health information was from friends, family members, and community leaders. Some of the identified enablers to community health communication include awareness programme via Non-Governmental Organisations (NGOs), community-based organisations such as faith-based organisations and healthcare facilities. Others are traditional media and social media. The identified barriers to community-based health communication include lack of knowledge and poverty, language barriers, and other miscellaneous issues including misuse of internet, lack of basic amenities and religious beliefs. The community-based healthcare providers articulated ways to overcome the identified barriers, including enlightenment programmes, using the language of the target audience, funding health awareness programmes, and monitoring of health education interventions. This study concludes that dissemination of health information using numerous channels is essential in ensuring population-wide primary prevention of diseases

Spatiotemporal dynamics of quantum jumps with Rydberg atoms

We study the nonequilibrium dynamics of quantum jumps in a one-dimensional chain of atoms. Each atom is driven on a strong transition to a short-lived state and on a weak transition to a metastable state. We choose the metastable state to be a Rydberg state so that when an atom jumps to the Rydberg state, it inhibits or enhances jumps in the neighboring atoms. This leads to rich spatiotemporal dynamics that are visible in the fluorescence of the strong transition.Comment: 10 page

Dividing the Ontology Alignment Task with Semantic Embeddings and Logic-based Modules

Large ontologies still pose serious challenges to state-of-the-art ontology alignment systems. In this paper we present an approach that combines a neural embedding model and logic-based modules to accurately divide an input ontology matching task into smaller and more tractable matching (sub)tasks. We have conducted a comprehensive evaluation using the datasets of the Ontology Alignment Evaluation Initiative. The results are encouraging and suggest that the proposed method is adequate in practice and can be integrated within the workflow of systems unable to cope with very large ontologies

Pattern formation with trapped ions

Ion traps are a versatile tool to study nonequilibrium statistical physics, due to the tunability of dissipation and nonlinearity. We propose an experiment with a chain of trapped ions, where dissipation is provided by laser heating and cooling, while nonlinearity is provided by trap anharmonicity and beam shaping. The collective dynamics are governed by an equation similar to the complex Ginzburg-Landau equation, except that the reactive nature of the coupling leads to qualitatively different behavior. The system has the unusual feature of being both oscillatory and excitable at the same time. We account for noise from spontaneous emission and find that the patterns are observable for realistic experimental parameters. Our scheme also allows controllable experiments with noise and quenched disorder.Comment: 4 pages + appendi