18,987 research outputs found
Teachers matter: feelings of school connectedness and positive youth development among Coos County youth
Students who feel positively about their education, have a sense of belonging in school, and maintain good relationships with students and staff generally feel connected to their schools. In fact, 63 percent of Coos youth report feeling this way. It is one of the most important factors in promoting socio-emotional well-being and positive youth development, according to authors Nena Stracuzzi and Meghan Mills. Their research, using surveys of Coos students, shows that students who feel more connected to their schools usually get better grades, have higher self-esteem, use fewer substances, and engage in aggressive behaviors less frequently. Their latest brief also shows that Coos County students who feel their teachers are supportive of them are often more connected to their schools
A Comparison between Electroluminescence Models and Experimental Results
Electrical insulation ages and degrades until its eventual failure under electrical stress. One cause of this relates to the movement and accumulation of charge within the insulation. The emission of a low level of light from polymeric materials while under electrical stressing occurs before the onset of currently detectable material degradation. This light is known as electroluminescence (EL) and under an ac electric field is thought to relate to the interaction of charge in close proximity to the electrode-polymer interface. Understanding the cause of this light emission gives a very high-resolution method of monitoring charge interaction and its influence on material ageing. A possible cause of this light emission is the bipolar charge recombination theory. This theory involves the injection, trapping and recombination of charge carriers during each half cycle of the applied field [1]. This work compares two models that to simulate the EL emission according to this bipolar charge recombination theory. Model 1 assumes a fixed space charge region and all injected charge is uniformly distributed in this region with charges able to either become trapped or to recombine with opposite polarity charge carriers [2]. This recombination relates directly the excitation needed for the emission of a photon of light as measured in experiments. Model 2 develops on this by accounting for the transport and extraction of charge with an exponential distribution of trap levels rather than a uniform distribution [3]. Figure 1 shows a good correlation between the two models and experimental data. The full paper will describe the models in more detail and present results comparing the simulated and experimental results under various applied waveforms. Model 1 and model 2 both provide a good correlation with experimental data but model 2 allows a greater understanding of the space charge profile in the region close to the electrodes as well as the shape of the conduction current. Further work involves developing these models to support changes in the charge trapping profiles due to material ageing and supporting simulated results with measured conduction current
Coyote space use in relation to prey abundance
Food abundance is an important factor determining space use in many species, but its effect on carnivore home range and territory size has rarely been investigated. We explored the relationship between food abundance for the coyote (Canis latrans) and space use in two study areas in the northern Great Basin, where the primary prey, the black-tailed jackrabbit (Lepus californicus), fluctuates dramatically in abundance. At one site, home ranges and temtories were significantly larger during a time of prey scarcity than when prey was abundant. Coyotes on the second site had similar-size home ranges and territories at low and high prey abundance, but a higher proportion and probably a higher number of individuals were transients during the prey-scarcity period. We propose mortality rates of coyotes as an important factor mediating adjustments in space use to food abundance, and suggest two mechanisms by which mortality might interact with food abundance. Higher mortality rates may simply permit more rapid adjustment of home range size to changing food conditions. Alternatively, higher mortality may selectively eliminate transients, thus reducing the impact of intruders in limiting the size of the remaining territories
Equivalence between two-dimensional alternating/random Ising model and the ground state of one-dimensional alternating/random XY chain
It is derived that the two-dimensional Ising model with alternating/random
interactions and with periodic/free boundary conditions is equivalent to the
ground state of the one-dimensional alternating/random XY model with the
corresponding periodic/free boundary conditions. This provides an exact
equivalence between a random rectangular Ising model, in which the
Griffiths-McCoy phase appears, and a random XY chain.Comment: 10 page
Carbon nanotube: a low-loss spin-current waveguide
We demonstrate with a quantum-mechanical approach that carbon nanotubes are
excellent spin-current waveguides and are able to carry information stored in a
precessing magnetic moment for long distances with very little dispersion and
with tunable degrees of attenuation. Pulsed magnetic excitations are predicted
to travel with the nanotube Fermi velocity and are able to induce similar
excitations in remote locations. Such an efficient way of transporting magnetic
information suggests that nanotubes are promising candidates for memory devices
with fast magnetization switchings
Epitaxial Ferromagnetic Nanoislands of Cubic GdN in Hexagonal GaN
Periodic structures of GdN particles encapsulated in a single crystalline GaN
matrix were prepared by plasma assisted molecular beam epitaxy. High resolution
X-ray diffractometery shows that GdN islands, with rock salt structure are
epitaxially oriented to the wurtzite GaN matrix. Scanning transmission electron
microscopy combined with in-situ reflection high energy electron diffraction
allows for the study of island formation dynamics, which occurs after 1.2
monolayers of GdN coverage. Magnetometry reveals two ferromagnetic phases, one
due to GdN particles with Curie temperature of 70K and a second, anomalous room
temperature phase.Comment: 4 pages, 3 figure
Manny Jinny\u27s Jubilee / music by Lewis F. Muir; words by L. Wolfe Gilbert
Cover: drawing of a large crowd coming to visit Mammy Jinny, most of the crowd bears gifts: a chicken, a watermelon, flowers; photo inset of two Caucasians: Valeska Suratt and George Baldwin. (see 428); Publisher: F. A. Mills (New York)https://egrove.olemiss.edu/sharris_c/1053/thumbnail.jp
Take Me to that Swanee Shore / music by Lewis F. Muir; words by L. Wolfe Gilbert
Cover: a profile photo of a woman; photo inset of George Austin Moore; Publisher: F. A. Mills (New York)https://egrove.olemiss.edu/sharris_c/1046/thumbnail.jp
Mammy Jinny\u27s Jubilee / music by Lewis F. Muir; words by L. Wolfe Gilbert
Cover: drawing of a large crowd coming to visit Mammy Jinny, most of the crowd bears gifts: a chicken, a watermelon, flowers; photo inset of Gillen Beck and Frazer. (see #74); Publisher: F. A. Mills (New York)https://egrove.olemiss.edu/sharris_c/1060/thumbnail.jp
A Multidiscipline Approach to Mitigating the Insider Threat
Preventing and detecting the malicious insider is an inherently difficult problem that expands across many areas of expertise such as social, behavioral and technical disciplines. Unfortunately, current methodologies to combat the insider threat have had limited success primarily because techniques have focused on these areas in isolation. The technology community is searching for technical solutions such as anomaly detection systems, data mining and honeypots. The law enforcement and counterintelligence communities, however, have tended to focus on human behavioral characteristics to identify suspicious activities. These independent methods have limited effectiveness because of the unique dynamics associated with the insider threat. The solution requires a multidisciplinary approach with a clearly defined methodology that attacks the problem in an organized and consistent manner. The purpose of this paper is to present a framework that provides a systematic way to identify the malicious insider and describe a methodology to counter the threat. Our model, the Multidiscipline Approach to Mitigating the Insider Threat (MAMIT), introduces a novel process for addressing this challenge. MAMIT focuses on the collaboration of information from the relative disciplines and uses indicators to produce a consolidated matrix demonstrating the likelihood of an individual being a malicious insider. The well-known espionage case study involving Robert Hanssen is used to illustrate the effectiveness of the framework
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