The Realities of K-12 Virtual Education

In a decade, virtual education in its contemporary form of asynchronous, computer-mediated interaction between a teacher and students over the Internet has grown from a novelty to an established mode of education that may provide all or part of formal schooling for nearly one in every 50 students in the US. In a non-random 2007 survey of school districts, as many as three out of every four public K-12 school districts responding reported offering full or partial online courses.There can be little question that virtual courses in certain areas (e.g., math, English, social studies) produce tested achievement results on a par with those of their conventionally taught counterparts. Nor is it debatable that more complex areas of the curriculum (e.g., the arts) are beyond the reach of these new arrangements. Nevertheless, the rapid growth of this new form of schooling raises questions of cost, funding, and variable quality that require the immediateattention of policymakers

A finitely presented orderable group with insoluble word problem

We construct a finitely presented (two-sided) totally orderable group with insoluble word problem.Comment: 17 page

High-Stakes Testing and Student Achievement: Problems for the No Child Left Behind Act

Under the federal No Child Left Behind Act of 2001 (NCLB), standardized test scores are the indicator used to hold schools and school districts accountable for student achievement. Each state is responsible for constructing an accountability system, attaching consequences -- or stakes -- for student performance. The theory of action implied by this accountability program is that the pressure of high-stakes testing will increase student achievement. But this study finds that pressure created by high-stakes testing has had almost no important influence on student academic performance

2. Testing Old, Testing New: Schoolboy Psychology and the Allocation of Intellectual Resources

There will be no divining of the future here- no megatrends, no reference to Orwell (except this one). What little we truly know about the future does not bear mentioning. Nor shall I refer to micro-computers, data banks, and other gaudy paraphernalia that the future holds for us. The future is best seen in a rear-view mirror. We can at least hope to see more clearly the recent past we have traversed. Appearances of rapid change are usually superficial. If we see the past and present clearly, we will know as much of our future as it is ever permitted us to know. Kenneth Boulding (1968) contends that the discovery of knowledge is absolutely unpredictable, since knowledge is the one thing that if we could predict when we would discover it we would have it already. The evolution of a technology, if it were not really radically new, might be predicted with some success; but then, if we can\u27t predict the discovery of new knowledge and we can only predict changes in ordinary technology, then surely we have little idea of the important changes that lie ahead. New knowledge is revolutionary; technology is Establishment. The discovery of knowledge upsets things, changes the way lives are led. Technology serves old entrenched interests and established institutions. The glacial evolution of testing in this century reveals the source of its momentum- new technologies are moving it, not new knowledge. Testing is the conservative wing of the Social Science party. A Point of View: Abstracted Empiricism The most revealing perspective to assume for viewing the evolution and the current condition of testing is that which affords the clearest picture of how testing relates to the basic disciplines in the study of human behavior. In the last 100 years, testing has moved gradually from the center to the periphery of the behavioral and social sciences. Once an integral part of the best thinking on human development and behavior, testing\u27 has progressively grown more inbred and dissociated from the leading theoretical positions in psychology and the social sciences. In its position at the margin, testing has come to serve more faithfully the goals of its own professional subculture and of a particular political subculture (i.e., its own intellectual Establishment and the professional-managerial Establishment) than to serve the ends of science and the true aims of education. To fulfill its promise, testing must find its way back to the center of psychological thinking. My message here does little more than echo a theme sounded by Anne Anastasi (1967) in her 1966 presidential address to Division 5 of the American Psychological Association. . . . Psychological testing is becoming dissociated from the mainstream of contemporary psychology. Those psychologists specializing in psychometrics have been devoting more and more of their efforts to refining the techniques of test construction, while losing sight of the behavior they set out to measure. Psychological testing today places too much emphasis on testing and too little on psychology. As a result, outdated interpretations of test performance may remain insulated from the impact of subsequent behavior research. It is my contention that the isolation of psychometrics from other relevant areas of psychology is one of the conditions that have led to the prevalent public hostility toward testing (p. 297). Although the very essence of psychological testing is the measurement of behavior, testing today is not adequately assimilating relevant developments from the science of behavior. ... It is noteworthy that the term “test theory generally refers to the mechanics of test construction, such as the nature of the score scale and the procedures for assessing reliability and validity. The term does not customarily refer to psychological theory about the behavior under consideration. Psychometricians appear to shed much of their psychological knowledge as they concentrate upon the minutiae of elegant statistical techniques. Moreover, when other types of psychologists use standardized tests in their work, they too show a tendency to slip down several notches in psychological sophistication (p. 300)

2. Testing Old, Testing New: Schoolboy Psychology and the Allocation of Intellectual Resources

There will be no divining of the future here- no megatrends, no reference to Orwell (except this one). What little we truly know about the future does not bear mentioning. Nor shall I refer to micro-computers, data banks, and other gaudy paraphernalia that the future holds for us. The future is best seen in a rear-view mirror. We can at least hope to see more clearly the recent past we have traversed. Appearances of rapid change are usually superficial. If we see the past and present clearly, we will know as much of our future as it is ever permitted us to know. Kenneth Boulding (1968) contends that the discovery of knowledge is absolutely unpredictable, since knowledge is the one thing that if we could predict when we would discover it we would have it already. The evolution of a technology, if it were not really radically new, might be predicted with some success; but then, if we can\u27t predict the discovery of new knowledge and we can only predict changes in ordinary technology, then surely we have little idea of the important changes that lie ahead. New knowledge is revolutionary; technology is Establishment. The discovery of knowledge upsets things, changes the way lives are led. Technology serves old entrenched interests and established institutions. The glacial evolution of testing in this century reveals the source of its momentum- new technologies are moving it, not new knowledge. Testing is the conservative wing of the Social Science party. A Point of View: Abstracted Empiricism The most revealing perspective to assume for viewing the evolution and the current condition of testing is that which affords the clearest picture of how testing relates to the basic disciplines in the study of human behavior. In the last 100 years, testing has moved gradually from the center to the periphery of the behavioral and social sciences. Once an integral part of the best thinking on human development and behavior, testing\u27 has progressively grown more inbred and dissociated from the leading theoretical positions in psychology and the social sciences. In its position at the margin, testing has come to serve more faithfully the goals of its own professional subculture and of a particular political subculture (i.e., its own intellectual Establishment and the professional-managerial Establishment) than to serve the ends of science and the true aims of education. To fulfill its promise, testing must find its way back to the center of psychological thinking. My message here does little more than echo a theme sounded by Anne Anastasi (1967) in her 1966 presidential address to Division 5 of the American Psychological Association. . . . Psychological testing is becoming dissociated from the mainstream of contemporary psychology. Those psychologists specializing in psychometrics have been devoting more and more of their efforts to refining the techniques of test construction, while losing sight of the behavior they set out to measure. Psychological testing today places too much emphasis on testing and too little on psychology. As a result, outdated interpretations of test performance may remain insulated from the impact of subsequent behavior research. It is my contention that the isolation of psychometrics from other relevant areas of psychology is one of the conditions that have led to the prevalent public hostility toward testing (p. 297). Although the very essence of psychological testing is the measurement of behavior, testing today is not adequately assimilating relevant developments from the science of behavior. ... It is noteworthy that the term “test theory generally refers to the mechanics of test construction, such as the nature of the score scale and the procedures for assessing reliability and validity. The term does not customarily refer to psychological theory about the behavior under consideration. Psychometricians appear to shed much of their psychological knowledge as they concentrate upon the minutiae of elegant statistical techniques. Moreover, when other types of psychologists use standardized tests in their work, they too show a tendency to slip down several notches in psychological sophistication (p. 300)

Program for refan JT8D engine design, fabrication and test, phase 2

The objective of the JT8D refan program was to design, fabricate, and test certifiable modifications of the JT8D engine which would reduce noise generated by JT8D powered aircraft. This was to be accomplished without affecting reliability and maintainability, at minimum retrofit cost, and with no performance penalty. The mechanical design, engine performance and stability characteristics at sea-level and altitude, and the engine noise characteristics of the test engines are documented. Results confirmed the structural integrity of the JT8D-109. Engine operation was stable throughout the airplane flight envelope. Fuel consumption of the test engines was higher than that required to meet the goal of no airplane performance penalty, but the causes were identified and corrected during a normal pre-certification engine development program. Compared to the baseline JT8D-109 engine, the acoustically treated JT8D-109 engine showed noise reductions of 6 PNdB at takeoff and 11 PNdB at a typical approach power setting

X-ray rocking curve study of Si-implanted GaAs, Si, and Ge

Crystalline properties of Si-implanted GaAs, Si, and Ge have been studied by Bragg case double-crystal x-ray diffraction. Sharp qualitative and quantitative differences were found between the damage in GaAs on one hand and Si and Ge on the other. In Si and Ge the number of defects and the strain increase linearly with dose up to the amorphous threshold. In GaAs the increase in these quantities is neither linear nor monotonic with dose. At a moderate damage level the GaAs crystal undergoes a transition from elastic to plastic behavior. This transition is accompanied by the creation of extended defects, which are not detected in Si or Ge

The optical-ultraviolet continuum of Seyfert 2 galaxies

This paper aims to understand the continuum of Seyfert 2 galaxies. By fitting the single galaxies in the sample of Heckman et al. (1995) with composite models (shock+ photoionization from the active center), we show that five main components characterize the SED of the continuum. Shocks play an important role since they produce a high temperature zone where soft X-rays are emitted. We show that in the optical-UV range, the slope of the NLR emission reproduces the observed values, and may be the main component of the featureless continuum. The presence of star forming regions cannot be excluded in the circumnuclear region of various Seyfert galaxies. An attempt is made to find their fingerprints in the observed AGN spectra. Finally, it is demonstrated that multi-cloud models are necessary to interpret the spectra of single objects, even in the global investigation of a sample of galaxies.Comment: 26 pages, LaTeX (including 5 Tables) + 17 PostScript figures. To appear in "The Astrophysical Journal

Features of pulsed synchronization of a systems with a tree-dimensional phase space

Features of synchronization picture in the system with the limit cycle embedded in a three-dimensional phase space are considered. By the example of Ressler system and Dmitriev - Kislov generator under the action of a periodic sequence of delta - function it is shown, that synchronization picture significantly depends on the direction of pulse action. Features of synchronization tons appeared in these models are observed.Comment: 16 pages, 11 figure