Effects of anisotropic conduction and heat pipe interaction on minimum mass space radiators

Equations are formulated for the two dimensional, anisotropic conduction of heat in space radiator fins. The transverse temperature field was obtained by the integral method, and the axial field by numerical integration. A shape factor, defined for the axial boundary condition, simplifies the analysis and renders the results applicable to general heat pipe/conduction fin interface designs. The thermal results are summarized in terms of the fin efficiency, a radiation/axial conductance number, and a transverse conductance surface Biot number. These relations, together with those for mass distribution between fins and heat pipes, were used in predicting the minimum radiator mass for fixed thermal properties and fin efficiency. This mass is found to decrease monotonically with increasing fin conductivity. Sensitivities of the minimum mass designs to the problem parameters are determined

The Effects of Wear on Wool Fabrics

“Will it wear?” This is a question commonly asked by the customer when confronted with a great many bolts of fabric of numerous patterns and weights. When the clothing budget is limited it is especially important that one choose a fabric that will give the most service. Often the customer wants to know, “Will the heavier material wear longer than the lightweight material?” Unfortunately, no one has found a way to answer these questions definitely by laboratory tests alone. The term “wear,” as used by the consumer, is a broad term. Not only is wear itself a part of the picture, but dry cleaning, aging, exposure to light, and any other treatment the garment must stand have something to do with how long it will last. All the “extra” treatment a garment receives, such as bending, rubbing, and creasing, makes it difficult to reproduce in the laboratory the actual effects of wear. So in order to study the wearing qualities of one type of fabric, 27 pairs of trousers were made from an all-wool material of three different weights. Nine pairs of trousers were made from each weight of material. This allowed three pairs for each wear period, thus avoiding the undue influence of one person’s wearing habits on the test. The trousers were worn by men students at South Dakota State College for one, two and three periods, each wear period being 1500 hours. This means that three pairs of each weight were worn 1500 hours, three pairs worn 3000 hours and three pairs, 4500 hours. The trousers were dry cleaned and inspected after every 300 hours of wear. Lengths of the same material were set aside as “control” fabrics. This material was not worn, of course, but was paired with the trousers and received the same amount of dry cleaning and aging as the worn garments. Another set of pieces was stored for a corresponding period without cleaning. By checking the fabric measurements of these samples against those of the worn trousers, it was possible to discover the separate and combined effects of wear, of dry cleaning, and of aging

Priorities vs. Reality: A Task Analysis of Secondary School Principals in the State of Minnesota

Abstract “The principal’s role in delivering quality education has long been recognized as an important organizational characteristic of schools. How principals should perform their roles, however, has been the subject of debate” (Smith & Andrews, 1989, p. 21). Since the inception of the principalship, the role of the principal has encompassed all operations of their school. During the early 1900s principals were primarily managers of facilities. Principals were predominately male teachers who performed clerical administrative duties such as the school schedule, length of year, facility management etc. (Kafka, 2009). As the role of education in our society has grown, so has the principalship. Each decade has brought changes to public schools as the needs of society have changed. Schools grow and change, and at the head of each school is a principal who is responsible for this growth and change (Goodwin, Cunningham, & Eagle, 2005). During the 1950s and 1960s, our country went through turbulent times in the arenas of social change and global competition. Schools became the focus of change in order to help solve the inequities in society and to help us compete scientifically and economically on the world stage. By the 1970s, our educational systems ranking on the world stage started to suffer. Principals were directed to focus on instructional leadership in order to better prepare our students to compete globally. Rigorous education of children was prioritized as a means for America to better compete in the global society (Drake & Roe, 1994). “His cardinal function is the improvement of instruction, which will enhance the learning experiences of his students” (Melton, 1970, p. 2). Society has seen major changes over the past 100 years, socially and scientifically. Technology is now part of our schools and everyday experience. As society has evolved, so has public education and the role of the public school principal. Duties have been added to the principalship, nothing has been deleted. The management issues of previous decades still exist and the instructional leadership duties continue be expanded upon. With all the responsibilities of today’s principalship, what are the most important functions for principals to perform? There is continuous conflict within the definition of the principalship as instructional leader or building manager or both (Portin & Jianping, 1999). “The historical conflict between the instructional leadership role and managerial aspects of the principalship has had a major impact on the entire profession” (Richardson, 1991, p. 9). The purpose of this study is to determine those leadership tasks that consume the majority of Minnesota secondary school principals’ time. The study will examine Minnesota secondary school principals’ perceptions of those tasks they believe should consume the majority of their time. These perceptions will be compared to Minnesota secondary school principals’ reported time on job-related tasks. The study will ascertain whether or not Minnesota secondary school principals’ perceived priority tasks match actual time on task and if they spend more time providing instructional leadership or managerial leadership

Discovery of a new INTEGRAL source: IGR J19140+0951

IGR J19140+0951 (formerly known as IGR J19140+098) was discovered with the INTEGRAL satellite in March 2003. We report the details of the discovery, using an improved position for the analysis. We have performed a simultaneous study of the 5-100 keV JEM-X and ISGRI spectra from which we can distinguish two different states. From the results of our analysis we propose that IGR J19140+0951 is a persistent Galactic X-ray binary, probably hosting a neutron star although a black hole cannot be completely ruled out.Comment: 4 pages, 4 figures. Accepted for publication in A&A

Analysis of radiative and phase-change phenomena with application to space-based thermal energy storage

The simplified geometry for the analysis is an infinite, axis symmetric annulus with a specified solar flux at the outer radius. The inner radius is either adiabatic (modeling Flight Experiment conditions), or convective (modeling Solar Dynamic conditions). Liquid LiF either contacts the outer wall (modeling ground based testing), or faces a void gap at the outer wall (modeling possible space based conditions). The analysis is presented in three parts: Part 3 considers and adiabatic inner wall and linearized radiation equations; part 2 adds effects of convection at the inner wall; and part 1 includes the effect of the void gap, as well as previous effects, and develops the radiation model further. The main results are the differences in melting behavior which can occur between ground based 1 g experiments and the microgravity flight experiments. Under 1 gravity, melted PCM will always contact the outer wall having the heat flux source, thus providing conductance from this source to the phase change front. In space based tests where a void gap may likely form during solidification, the situation is reversed; radiation is now the only mode of heat transfer and the majority of melting takes place from the inner wall

\u3cem\u3eLawrence v. Texas\u3c/em\u3e and Judicial Hubris

The republic will no doubt survive the Supreme Court\u27s decision, in Lawrence v. Texas, to invalidate laws against private, consensual sodomy, including those limited to homosexual behavior. Such laws are almost never enforced, and the rare prosecutions for such acts are necessarily capricious. So the principal direct effect of the Court\u27s decision is likely to be extremely limited, and largely salutary: a few individuals will be spared the bad luck of getting a criminal conviction for violating laws that are manifestly out of step with prevailing sexual mores. Nor are we likely to see anything like the intense political opposition generated by this decision\u27s most important doctrinal ancestor, Roe v. Wade. Millions of Americans regard Roe as judicial authorization for mass murder, and understandably continue to oppose the Court\u27s approach to abortion. One can hardly foresee a similar passion for overturning a judicial decision that merely eliminates a few haphazard prosecutions for private conduct that has no immediate effect on any third parties. Judging at least by what we see in the general press and popular entertainment media, most of the public can be counted on to respond to the immediate consequences of Lawrence with a yawn. If the Court was looking for a case in which to flex its political muscles with impunity, it could hardly have found a better candidate

A Protocol for Generating Random Elements with their Probabilities

We give an AM protocol that allows the verifier to sample elements x from a probability distribution P, which is held by the prover. If the prover is honest, the verifier outputs (x, P(x)) with probability close to P(x). In case the prover is dishonest, one may hope for the following guarantee: if the verifier outputs (x, p), then the probability that the verifier outputs x is close to p. Simple examples show that this cannot be achieved. Instead, we show that the following weaker condition holds (in a well defined sense) on average: If (x, p) is output, then p is an upper bound on the probability that x is output. Our protocol yields a new transformation to turn interactive proofs where the verifier uses private random coins into proofs with public coins. The verifier has better running time compared to the well-known Goldwasser-Sipser transformation (STOC, 1986). For constant-round protocols, we only lose an arbitrarily small constant in soundness and completeness, while our public-coin verifier calls the private-coin verifier only once

Lawrence v. Texas and Judicial Hubris

Lawrence v. Texas produces a desirable policy result, but it deserves condemnation as a legal decision. It repudiates the Supreme Court\u27s most recent attempt to put doctrinal restraints on the most anticonstitutional doctrine in constitutional law - substantive due process. That doctrine, for which the Court has never provided a successful textual justification, has been selectively employed over the decades to advance a variety of political agendas popular with Supreme Court majorities. In 1938, Carolene Products put meaningful restraints on substantive due process, taming that doctrine for about a quarter of a century. With Griswold and Roe v. Wade, the Court adopted a new substantive due process agenda - sexual freedom. In Washington v. Glucksberg, the Court sought to restore most of the limits of the Carolene Products approach, while leaving the Griswold-Roe line in place, by adopting a test requiring that newly recognized rights be deeply rooted in the nation\u27s history and tradition. Lawrence repudiates the Glucksberg approach and instead deploys an undisciplined form of judicial mysticism. Notwithstanding the availability of plausible arguments based on precedent to invalidate the Texas law, the Lawrence Court chose instead to rely on a series of utterly untenable arguments and analytically empty bombast. We argue that the Lawrence approach is not law in any meaningful sense of the term, but only a vehicle for judges to impose their own political preferences on the nation. We also rebut some justifications that could be offered in defense of Lawrence. We show that Professor Robert Post\u27s concept of a conversation between the Court and the nation obliterates the concept of law as something distinct from politics, and offers a theory of judicial review that would justify even a decision like Plessy v. Ferguson. Second, we show that Professor Randy Barnett fails in his effort to provide Lawrence with a foundation in the Constitution because he misinterprets the Ninth Amendment and the Privileges or Immunities Clause. Third, we rebut those who would defend Lawrence on pragmatic grounds by explaining why we think competitive federalism is a far superior mechanism for creating new norms of liberty, and for correcting the mistakes that are inevitable in any process of policy development. Finally, we outline the case for repudiating the Griswold-Roe-Lawrence line of cases and for using the Glucksberg test to return the Court\u27s substantive due process jurisprudence roughly to where it stood as a result of Carolene Products

Enhancing quality and equity? Performance assessment validation in examination physical education in Western Australia

The positioning and format of performance assessment in examination physical education varies between courses across Australia and internationally. This paper centres on developments in performance assessment in the Physical Education Studies (PES) course in Western Australia (WA). In 2021 The School Curriculum and Standards Authority (SCSA) undertook an assessment validation trial of school-based assessment of students participating in modified format competitive game play in the 10 PES sports. This contrasted to existing centralised examination arrangements. The paper reports on findings from observation of the trial in nine of the 10 sport contexts, and semi-structured interviews with teachers, validators and SCSA staff. Analysis drew on conceptualisations of quality assessment to critically examine features of assessment information collection and judgement processes in the trial and the inter-relationships between these two elements of assessment. Discussion highlights issues of quality and equity in performance assessment for future policy and research to consider