A General Theorem Relating the Bulk Topological Number to Edge States in Two-dimensional Insulators

We prove a general theorem on the relation between the bulk topological quantum number and the edge states in two dimensional insulators. It is shown that whenever there is a topological order in bulk, characterized by a non-vanishing Chern number, even if it is defined for a non-conserved quantity such as spin in the case of the spin Hall effect, one can always infer the existence of gapless edge states under certain twisted boundary conditions that allow tunneling between edges. This relation is robust against disorder and interactions, and it provides a unified topological classification of both the quantum (charge) Hall effect and the quantum spin Hall effect. In addition, it reconciles the apparent conflict between the stability of bulk topological order and the instability of gapless edge states in systems with open boundaries (as known happening in the spin Hall case). The consequences of time reversal invariance for bulk topological order and edge state dynamics are further studied in the present framework

Optimizing Maintenance Activities Second Report: Snow and Ice Control Operations

FH-11-8250This report presents the major results of an in-depth study of Snow and Ice Control Operations conducted in four States during the winter of 1975-76. The states involved were California, Colorado, Pennsylvania, and Utah. To the extent possible, within the time frame of the study, all aspects of snow and ice control activities (material, equipment and labor) were analyzed. Initial estimates indicate potential savings on the order of $5 million among the four states upon implementation of the changes recommended as a result of this project. The recommendation with the greatest potential for immediate cost reduction are the control of application rates and the adoption of ground control spreaders

Public Health Outcome Measures Report [captured 06-30-2006] /

The Utah Department of Health, Public Health Outcome Measures Report is intended to provide easy access to information about Utah's priority public health objectives. The Utah Department of Health regularly examines outcome measures to: Track and evaluate progress toward goals Guide policy decisions, priorities and long-range strategic plans Enhance performance-orientation and overall accountability Develop, focus, and streamline data collection and reporting capacity Provide comprehensive information of Utah's health and health care systemrepor

Salt Lake City parking study.

Mode of access: Internet

Utah health status update /

Periodic updates of health status information on various subjects

Utah nonpoint source pollution management plan

Nonpoint source pollution (NPS) is pollution that results from diffuse sources in contrast to pollutants which enter waterways from pipes or other man-made conveyances. NPS pollution can include a variety of contaminates such as sediments, nutrients, pesticides, bacteria, organics and heavy metals that enter surface waters or leach into groundwater. Some common sources of NPS pollution include urban streets and parking lots, agricultural lands and operations, and construction sites

Southern Utah University [CD]/ Communication Dept Southern Utah University

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Bureau of Epidemiology Annual Report 2001

Annual disease reports.repor

Bureau of Epidemiology Annual Report 1992

Annual disease reports.repor