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Designing, implementing, and evaluating a staff development project to improve student performance using a whole language cooperative learning approach.
This dissertation describes the design, implementation and assessment of a staff development project to develop a cooperative whole language approach. The foundation for this staff development project for elementary school was the recognition that language development is crucial to a child\u27s ability to succeed in the school environment. The educational objectives of this project were to motivate and encourage students of low income, African American families to write imaginatively and productively, and to teach writing to those same students to help them develop their own stylistic competence. These objectives necessitated the organization of three components. First, a staff development program focused on a whole language approach so teachers could share cooperative learning strategies for improving selected aspects of writing instruction. Second, a language experience approach in which the language, experience, and feelings of minority students could be used to advance motivation, accuracy, and pride. Third, the creation of a positive school climate to help students overcome difficulties in communicating in standard English by developing a school way of communicating without forcing the student to conclude that the way the family converses at home is wrong. Cooperative learning staff development sessions, predicated on a whole language approach, combined five underlying principles: (a) Distributed Leadership; (b) Heterogeneous Grouping; (c) Positive Interdependence; (d) Social Skills Acquisition; and (e) Group Autonomy. These prompted the preparation of writing activities for the African American students in all aspects of the curriculum. Ongoing monitoring of students\u27 progress and completed tasks were compiled in both a group and individual portfolios. Basic to the success of this project was overcoming six beliefs: (a) a single set of subcultural customs shape the behavior of African American members of our society; (b) language programs should involve only instruction in using standard English; (c) all African American children are apathetic and their classes are seldom exciting; (d) discipline is a unique problem in the African American classroom; (e) African American learners cannot become involved in inductive, inquiry centered learning; and, (f) staff development sessions are not required for teaching English to the African American child. The proposed goal of this effective staff development project was not to change, but, to add a new dialect to an existing one by using a child centered, whole language, cooperative learning approach. By mixing the students\u27 own experiences and the presentation of new experiences, a new dimension was introduced. The students were meeting established norms of success and were eager to accept additional challenges. Class improvement was clearly visible in a low income, urban elementary school
Coronal Shock Waves, EUV waves, and their Relation to CMEs. II. Modeling MHD Shock Wave Propagation Along the Solar Surface, Using Nonlinear Geometrical Acoustics
We model the propagation of a coronal shock wave, using nonlinear geometrical
acoustics. The method is based on the Wentzel-Kramers-Brillouin (WKB) approach
and takes into account the main properties of nonlinear waves: i) dependence of
the wave front velocity on the wave amplitude, ii) nonlinear dissipation of the
wave energy, and iii) progressive increase in the duration of solitary shock
waves. We address the method in detail and present results of the modeling of
the propagation of shock-associated extreme-ultraviolet (EUV) waves as well as
Moreton waves along the solar surface in the simplest solar corona model. The
calculations reveal deceleration and lengthening of the waves. In contrast,
waves considered in the linear approximation keep their length unchanged and
slightly accelerate.Comment: 15 pages, 7 figures, accepted for publication in Solar Physic
Reflections of Colonel Kim Ramos, USAF Ret, Interviewed by Robert Cardinal-Warmuth
Personal/professional reaction – violated, appalled anyone would attack soft (civilian) targets, most don’t realize the Pentagon is an office building dedicated to acquiring and organizing resources, all warfighting and military operations occur from the combatant commands (EUCOM, CENTCOM, PACOM, etc). Sadness for friends who lost loved ones. Surreal experiences as there was NO traffic (D.C. is famous for traffic at all hours of the day, every day) in the D.C. area and no sound of aircraft overhead (it was constant prior to 9/11). Over time, it became sadness/anger for the loss of freedom, safety, and cultural changes
Bayesian Generalized Probability Calculus for Density Matrices
One of the main concepts in quantum physics is a density matrix, which is a
symmetric positive definite matrix of trace one. Finite probability
distributions can be seen as a special case when the density matrix is
restricted to be diagonal.
We develop a probability calculus based on these more general distributions
that includes definitions of joints, conditionals and formulas that relate
these, including analogs of the Theorem of Total Probability and various Bayes
rules for the calculation of posterior density matrices. The resulting calculus
parallels the familiar "conventional" probability calculus and always retains
the latter as a special case when all matrices are diagonal. We motivate both
the conventional and the generalized Bayes rule with a minimum relative entropy
principle, where the Kullbach-Leibler version gives the conventional Bayes rule
and Umegaki's quantum relative entropy the new Bayes rule for density matrices.
Whereas the conventional Bayesian methods maintain uncertainty about which
model has the highest data likelihood, the generalization maintains uncertainty
about which unit direction has the largest variance. Surprisingly the bounds
also generalize: as in the conventional setting we upper bound the negative log
likelihood of the data by the negative log likelihood of the MAP estimator
Temperature and differential emission measure evolution of a limb flare on 13 January 2015
Context. Spatially unresolved observations show that the cooling phase in solar flares can be much longer than theoretical models predict. It has not yet been determined whether this is also the case for different subregions within the flare structure.
Aims. We aim to investigate whether or not the cooling times, which are observed separately in coronal loops and the supra-arcade fan (SAF), are in accordance with the existing cooling models, and whether the temperature and emission measure of supra-arcade downflows (SADs) are different from their surroundings.
Methods. We analysed the M5.6 limb flare on 13 January 2015 using SDO/AIA observations. We applied a differential emission measure (DEM) reconstruction code to derive spatially resolved temperature and emission measure maps, and used the output to investigate the thermal evolution of coronal loops, the SAF, and the SADs.
Results. In the event of 13 January 2015, the observed cooling times of the loop arcade and the SAF are significantly longer than predicted by the Cargill model, even with suppressed plasma heat conduction. The observed SADs show different temperature characteristics, and in all cases a lower density than their surroundings.
Conclusions. In the limb flare event studied here, continuous heating likely occurs in both loops and SAF during the gradual flare phase and leads to an extended cooling phase
Band gap engineering by Bi intercalation of graphene on Ir(111)
We report on the structural and electronic properties of a single bismuth
layer intercalated underneath a graphene layer grown on an Ir(111) single
crystal. Scanning tunneling microscopy (STM) reveals a hexagonal surface
structure and a dislocation network upon Bi intercalation, which we attribute
to a Bi structure on the underlying Ir(111)
surface. Ab-initio calculations show that this Bi structure is the most
energetically favorable, and also illustrate that STM measurements are most
sensitive to C atoms in close proximity to intercalated Bi atoms. Additionally,
Bi intercalation induces a band gap (eV) at the Dirac point of
graphene and an overall n-doping (eV), as seen in angular-resolved
photoemission spectroscopy. We attribute the emergence of the band gap to the
dislocation network which forms favorably along certain parts of the moir\'e
structure induced by the graphene/Ir(111) interface.Comment: 5 figure
Large-scale Bright Fronts in the Solar Corona: A Review of "EIT waves"
``EIT waves" are large-scale coronal bright fronts (CBFs) that were first
observed in 195 \AA\ images obtained using the Extreme-ultraviolet Imaging
Telescope (EIT) onboard the \emph{Solar and Heliospheric Observatory (SOHO)}.
Commonly called ``EIT waves", CBFs typically appear as diffuse fronts that
propagate pseudo-radially across the solar disk at velocities of 100--700 km
s with front widths of 50-100 Mm. As their speed is greater than the
quiet coronal sound speed (200 km s) and comparable to the
local Alfv\'{e}n speed (1000 km s), they were initially
interpreted as fast-mode magnetoacoustic waves ().
Their propagation is now known to be modified by regions where the magnetosonic
sound speed varies, such as active regions and coronal holes, but there is also
evidence for stationary CBFs at coronal hole boundaries. The latter has led to
the suggestion that they may be a manifestation of a processes such as Joule
heating or magnetic reconnection, rather than a wave-related phenomena. While
the general morphological and kinematic properties of CBFs and their
association with coronal mass ejections have now been well described, there are
many questions regarding their excitation and propagation. In particular, the
theoretical interpretation of these enigmatic events as magnetohydrodynamic
waves or due to changes in magnetic topology remains the topic of much debate.Comment: 34 pages, 19 figure
Coronal Shock Waves, EUV Waves, and Their Relation to CMEs. III. Shock-Associated CME/EUV Wave in an Event with a Two-Component EUV Transient
On 17 January 2010, STEREO-B observed in extreme ultraviolet (EUV) and white
light a large-scale dome-shaped expanding coronal transient with perfectly
connected off-limb and on-disk signatures. Veronig et al. (2010, ApJL 716, 57)
concluded that the dome was formed by a weak shock wave. We have revealed two
EUV components, one of which corresponded to this transient. All of its
properties found from EUV, white light, and a metric type II burst match
expectations for a freely expanding coronal shock wave including correspondence
to the fast-mode speed distribution, while the transient sweeping over the
solar surface had a speed typical of EUV waves. The shock wave was presumably
excited by an abrupt filament eruption. Both a weak shock approximation and a
power-law fit match kinematics of the transient near the Sun. Moreover, the
power-law fit matches expansion of the CME leading edge up to 24 solar radii.
The second, quasi-stationary EUV component near the dimming was presumably
associated with a stretched CME structure; no indications of opening magnetic
fields have been detected far from the eruption region.Comment: 18 pages, 10 figures. Solar Physics, published online. The final
publication is available at http://www.springerlink.co
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