638 research outputs found
Spectral and thermal mapping of desert surface sediments for agricultural development
A combination of multispectral, thermal and microwave data obtained from space and supported by ground measurements are used to investigate the surface sediment characteristics of a desert plain area in Egypt (El-Gallaba Plain, NW of Aswan). This plain once hosted an ancestral river system that is nowadays largely covered by aeolian and gravelly sands, and thus, only detectible with radar and thermal images. The methodology consists of extracting thermo-physical and textural parameters to guide and improve supervised spectral classification results. The results show that surface mineralogy (obtained from spectral information) correlates strongly with surface emissivity, whereas grain size and surface roughness strongly correlates with apparent thermal inertia. Furthermore, several broad strips of thermal cooling-anomalies are arranged in a linear fashion and diagonally crossing the alluvial basin. The sediments within these strips show very different textural, thermo-physical and compositional characteristics with respect to the surrounding areas suggesting that they were deposited under different depositional environments such as structurally controlled linear basins. These tectonic depressions were confirmed by ground penetrating radar and could be promising areas for groundwater accumulation and exploration enabling agricultural development in the El-Gallaba Plain of the Western Desert in Egypt
An Empirical Analysis of Identity Theft Determinants in the U.S.
This study finds that ID theft rates tend to be an increasing function of the unemployment rate and the proportion of the population concentrated in urban areas, and a decreasing function of the relative amount of resources devoted to laws enforcement and the percentage of individuals who claim a religious affiliation. We also find ID theft to be an increasing function of the extent of undocumented immigration, internet access, on the other hand, is found to negatively impact the incidence of ID theft, underscoring the decisive role of immigration and economic variables as determinants of ID theft. Educational attainment in the U.S. does not seem to be a factor
Power domination with random sensor failure
The power domination problem seeks to determine the minimum number of phasor
measurement units (PMUs) needed to monitor an electric power network. We
introduce random sensor failure before the power domination process occurs and
call this the fragile power domination process. For a given graph, PMU
placement, and probability of PMU failure , we study the expected number of
observed vertices at the termination of the fragile power domination process.
This expected value is a polynomial in , which we relate to fault-tolerant
and PMU-defect-robust power domination. We also study the probability of that
the entire graph becomes observed and give results for some graph families.Comment: 20 pages, 6 figure
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A description of the effects of a staff development project on the attitudes and commitment of a selected group of administrators : toward implementing management-by-objectives in an urban college.
Sexual Violence Prevention Training During Orientation
According to federal requirements, colleges and universities must provide sexual violence prevention programs to all new students. These requirements can prove complex, and orientation personnel must sift through all the information to determine what students need to know about sexual violence prevention. This topic is only growing in importance. Therefore, orientation personnel must remain informed and possess solid plans for information dissemination. This article provides a brief history of campus safety legislation, followed by the critical information students need to prevent sexual violence, including “How To Protect Themselves From Becoming a Victim,” “How To Protect Themselves From Becoming a Perpetrator,” “How To Protect Others From Becoming Victims,” and “How To Make Healthy Decisions About Sex and Relationships.
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Scenarios for Consuming Standardized Automated Demand Response Signals
Automated Demand Response (DR) programs require that Utility/ISO's deliver DR signals to participants via a machine to machine communications channel. Typically these DR signals constitute business logic information (e.g. prices and reliability/shed levels) as opposed to commands to control specific loads in the facility. At some point in the chain from the Utility/ISO to the loads in a facility, the business level information sent by the Utility/ISO must be processed and used to execute a DR strategy for the facility. This paper explores the various scenarios and types of participants that may utilize DR signals from the Utility/ISO. Specifically it explores scenarios ranging from single end user facility, to third party facility managers and DR Aggregators. In each of these scenarios it is pointed out where the DR signal sent from the Utility/ISO is processed and turned into the specific load control commands that are part of a DR strategy for a facility. The information in these signals is discussed. In some cases the DR strategy will be completely embedded in the facility while in others it may be centralized at a third party (e.g. Aggregator) and part of an aggregated set of facilities. This paper also discusses the pros and cons of the various scenarios and discusses how the Utility/ISO can use an open standardized method (e.g. Open Automated Demand Response Communication Standards) for delivering DR signals that will promote interoperability and insure that the widest range of end user facilities can participate in DR programs regardless of which scenario they belong to
Identification of false positive exercise tests with use of electrocardiographic criteria: A possible role for atrial repolarization waves
Atrial repolarization waves are opposite in direction to P waves, may have a magnitude of 100 to 200 mu V and may extend into the ST segment and T wave. It was postulated that exaggerated atrial repolarization waves during exercise could produce ST segment depression mimicking myocardial ischemia. The P waves, PR segments and ST segments were studied in leads II, III, aVF and V4 to V6 in 69 patients whose exercise electrocardiogram (ECG) suggested ischemia (100 mu V horizontal or 150 mu V upsloping ST depression 80 ms after the J point). All had a normal ECG at rest. The exercise test in 25 patients (52% male, mean age 53 years) was deemed false positive because of normal coronary arteriograms and left ventricular function (5 patients) or normal stress single photon emission computed tomographic thallium or gated blood pool scans (16 patients), or both (4 patients). Forty-four patients with a similar age and gender distribution, anginal chest pain and at least one coronary stenosis greater than or equal to 80% served as a true positive control group. The false positive group was characterized by (1) markedly downsloping PR segments at peak exercise, (2) longer exercise time and more rapidmore » peak exercise heart rate than those of the true positive group, and (3) absence of exercise-induced chest pain. The false positive group also displayed significantly greater absolute P wave amplitudes at peak exercise and greater augmentation of P wave amplitude by exercise in all six ECG leads than were observed in the true positive group.« les
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