22,788 research outputs found
Fate of Some Common Radionuclides Found in Dardanelle Lake
Four factors influence the concentrations of radionuclides in Dardanelle Lake water: injections due to fallout and discharge from Nuclear I coupled with losses due to decay, to dilution and to sedimentation. It is possible to estimate the first three factors and to measure monthly changes in the concentrations of Sr-89, Ce-141, Cs-137, Co-38, Ce-144, and Sr-90 - Y-90 during periods when the concentrations of these nuclides are abnormally high (after large releases or the Chinese weapons tests) or abnormally low (during reactor refueling)
Combined calculi for photon orbital and spin angular momenta
Context. Wavelength, photon spin angular momentum (PSAM), and photon orbital
angular momentum (POAM), completely describe the state of a photon or an
electric field (an ensemble of photons). Wavelength relates directly to energy
and linear momentum, the corresponding kinetic quantities. PSAMand POAM,
themselves kinetic quantities, are colloquially known as polarization and
optical vortices, respectively. Astrophysical sources emit photons that carry
this information. Aims. PSAM characteristics of an electric field (intensity)
are compactly described by the Jones (Stokes/Mueller) calculus. Similarly, I
created calculi to represent POAM characteristics of electric fields and
intensities in an astrophysical context. Adding wavelength dependence to all of
these calculi is trivial. The next logical steps are to 1) form photon total
angular momentum (PTAM = POAM + PSAM) calculi; 2) prove their validity using
operators and expectation values; and 3) show that instrumental PSAM can affect
measured POAM values for certain types electric fields. Methods. I derive the
PTAM calculi of electric fields and intensities by combining the POAM and PSAM
calculi. I show how these quantities propagate from celestial sphere to image
plane. I also form the PTAMoperator (the sum of the POAMand PSAMoperators),
with and without instrumental PSAM, and calculate the corresponding expectation
values. Results. Apart from the vector, matrix, dot product, and direct product
symbols, the PTAM and POAM calculi appear superficially identical. I provide
tables with all possible forms of PTAM calculi. I prove that PTAM expectation
values are correct for instruments with and without instrumental PSAM. I also
show that POAM measurements of "unfactored" PTAM electric fields passing
through non-zero instrumental circular PSAM can be biased. Conclusions. The
combined PTAM calculi provide insight into how to mathematically model PTAM
sources and calibrate POAMand PSAM- induced POAM measurement errors
Radionuclide Concentrations in the Arkansas River Upstream and Downstream from the Nuclear I Power Generating Facility
This report summarizes results obtained from a program designed to measure very low levels of some commonly produced radionuc1ides in the Dardenelle Lake area of the Arkansas River near the Arkansas Nuclear I Power Station operated by Arkansas Power and Light Company. The main thrust of this program was to determine the increase in the concentration of the radionuclides as a result of reactor operation as a function of their distance from the source. It was hoped to extend this study to include the effects of these emissions on the uptake of radionuclides into biological systems and their deposition in sediments
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Reform of the Foreign Intelligence Surveillance Courts: Procedural and Operational Changes
[Excerpt] The Foreign Intelligence Surveillance Act (FISA) of 1978 was the product of sweeping congressional investigation and deliberation prompted by perceived electronic surveillance abuses by the executive branch. Among other things, FISA established the Foreign Intelligence Surveillance Court (FISC) to review government applications to conduct electronic surveillance for foreign intelligence purposes and the Foreign Intelligence Surveillance Court of Review (FISA Court of Review) to review the decisions of the FISC. In the wake of revelations in June 2013 concerning the scope of orders issued by the FISC, many have questioned the efficacy of the current mechanisms for reviewing the executive branch’s intelligence gathering practices. While some have proposed altering the underlying substantive law that regulates such surveillance, other proposals address the practice and procedures of authorizing such surveillance activities.
This report begins with an overview of both the FISC and the FISA Court of Review, including the jurisdiction of these courts, how the judges are appointed, and the FISC’s practices and procedures for reviewing and issuing surveillance orders. The report then discusses the scope and underlying legal principles behind congressional regulation of the procedures of the federal courts, and applies those principles with respect to the various proposals to reform the FISA judicial review process. These reforms include requiring the FISC to hear arguments from “friends of the court” or amici curiae, who would brief the court on the privacy or civil liberty interests implicated by a government application; mandating that in certain instances the FISC sit en banc—that is, with all 11 FISC judges; and altering the voting rules of the FISC and FISA Court of Review
High-stakes testing
Relatively recent federal education initiatives, such as No Child Left Behind (NCLB;
2001), have focused on school accountability for student achievement including achievement of
traditionally at-risk populations, such as students in special education, students from low-income
or high poverty areas, and students who speak English as a new second language. Additionally,
these federal initiatives also mandate that all students take the same test measuring grade level
standards despite research that has demonstrated that students from at-risk populations are
sometimes at a disadvantage on high-stakes tests. Furthermore, initiatives such as NCLB are
often at odds with other education initiatives such as IDEA, which states that students in special
education should be tested at their respective level. Therefore, the current study proposed to
examine the relationship between Cattell-Horn-Carroll cognitive abilities and performance on a
state-wide high-stakes achievement test. There currently are no studies examining such a
relationship.
This study used Multivariate Regression Analysis, in order to investigate the relationship
between CHC cognitive and achievement abilities and performance on a state-wide high-stakes
achievement test, namely the ISTEP+, with 45 children who had been referred for a psychoeducational evaluation to determine special education eligibility and who had also taken
the ISTEP+. No statistically significant result was found between the WJ-III-COG broad CHC
abilities and performance on the English/Language Arts and Math performance of the ISTEP+.
Furthermore, no statistically significant result was found between the WJ-III-ACH and Math
performance on the ISTEP+. However, a statistically significant result was found between the
WJ-III-ACH Passage Comprehension subtest and the English/Language Arts portion of the
ISTEP+. The results indicated that students who had higher scores on the Passage
Comprehension subtest also had higher scores on the English/Language Arts portion of the
ISTEP+.
The current study took a step forward in the area of the relationship between CHC and
academic achievement, particularly state-mandated high-stakes testing given the dearth of
research in this area. Given the data from the current study indicating a statistically significant
relationship between Passage Comprehension and English/Language Arts from the ISTEP+, the
current study has practical implications for school psychologists, especially when school
psychologists are being asked to make predictions regarding a student’s academic achievement.
Results of the current study might help elucidate reading problems and recommended
interventions for those reading problems.Department of Educational PsychologyThesis (Ph. D.
DAMA/LIBRA findings urge replacement of the WIMP hypotheses by the daemon paradigm as a basis for experimental studies of DM objects
The simplest version of the daemon paradigm suggests the modulated 2-6-keV
range events in DAMA/NaI and DAMA/LIBRA detectors are caused by the iodine ions
knocked out elastically by the electrically neutral c-daemons moving with V =
30-50 km/s (c-daemon is a complex of negative daemon located in a remainder of
formerly captured nucleus where the daemon decomposes nucleons one by one with
~10^-6 s mean interval). Furthermore, after the 2-6 keV event occurred, in
subsequent ~10^-6 s, the c-daemon (which becomes negative during this time)
recaptures new nucleus with resulting scintillations in ~10 MeV range! The last
possibility was so far overlooked in the experiments as it did not stem from
WIMP hypotheses. A modification of the NaI(Tl) experiments is suggested for
revealing the effect described. Independently of the outcome, any obtained
result will be important for refining the daemon paradigm further on.Comment: 6 page
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