System optimization of gasdynamic lasers, computer program user's manual

The user's manual for a computer program that performs system optimization of gasdynamic lasers is provided. Detailed input/output formats are CDC 7600/6600 computers using a dialect of FORTRAN. Sample input/output data are provided to verify correct program operation along with a program listing

Assessing Graduate Student Needs and Structures of Support at Virginia Commonwealth University

The purpose of this multi-case study was to explore how the institutional landscape is designed to support graduate student success at Virginia Commonwealth University (VCU), a large, public, urban, R1 research university. The study included review of existing literature on the various factors that contribute to or limit graduate student success at institutions across the country. A major aim of this study was to collect qualitative data from participants with a key stake in this issue, including enrolled graduate students, and faculty/staff supporting graduate (master’s and doctoral) programs at VCU. Participants included 39 graduate students and 23 institutional stakeholders. All graduate students were invited to participate by email, with 39 final graduate students participating in seven, 60-90 minute focus groups of 6-8 students via Zoom with two members of the research team. Institutional stakeholders, with roles as full-time faculty or staff members at the university, were identified through institutional mapping and website review and invited via email, participated in 60-minute, one-on-one interviews via Zoom with one member of the research team. The study resulted in data coalescing around larger themes of graduate student support, factors promoting graduate student success, and challenges and barriers to success. A benchmarking comparison of VCU alongside peer institutions related to standards for graduate studies further identified areas of interest in 1) Programs and Services for Student Success, 2) Social Justice and Accessibility, 3) Collaboration, and 4) Assessment and Strategic Planning. Findings from the study indicated that, although VCU students appear to excel academically, there are challenges to graduate students balancing the demands of academic rigor with other obligations including, familial support, mental health and wellbeing needs, financial obligations, and social engagement. VCU students will continue to need increased support for funding, social connections, and referrals to appropriate resources. These findings have significant implications for structuring support for graduate students both at Virginia Commonwealth University and could influence institutions similarly situated across the country

Jastrow correlation factor for atoms, molecules, and solids

A form of Jastrow factor is introduced for use in quantum Monte Carlo simulations of finite and periodic systems. Test data are presented for atoms, molecules, and solids, including both all-electron and pseudopotential atoms. We demonstrate that our Jastrow factor is able to retrieve a large fraction of the correlation energy

Magellan: Preliminary description of Venus surface geologic units

Observations from approximately one-half of the Magellan nominal eight-month mission to map Venus are summarized. Preliminary compilation of initial geologic observations of the planet reveals a surface dominated by plains that are characterized by extensive and intensive volcanism and tectonic deformation. Four broad categories of units have been identified: plains units, linear belts, surficial units, and terrain units

Characterization and Compensation of the Residual Chirp in a Mach-Zehnder-Type Electro-Optical Intensity Modulator

We utilize various techniques to characterize the residual phase modulation of a fiber-based Mach-Zehnder electro-optical intensity modulator. A heterodyne technique is used to directly measure the phase change due to a given change in intensity, thereby determining the chirp parameter of the device. This chirp parameter is also measured by examining the ratio of sidebands for sinusoidal amplitude modulation. Finally, the frequency chirp caused by an intensity pulse on the nanosecond time scale is measured via the heterodyne signal. We show that this chirp can be largely compensated with a separate phase modulator. The various measurements of the chirp parameter are in reasonable agreement.Comment: 11 pages, 6 figure

Metabolism of a tropical rainforest stream

Gradients in photosynthesis (P) and respiration (R) were measured on an unperturbed portion of the Rio Mameyes, a tropical stream in the Luquillo Experimental Forest, northeastern Puerto Rico. Rates of P, which were similar to those of streams in temperate-deciduous forests, were low in the heavily canopied headwaters (\u3c70 g O2 m−2 y−1) and were higher (453–634 g O2 m−2 y−1) in middle and lower reaches. Periphyton biomass did not show the expected increase as the canopy opened downstream, probably because of increasing herbivory in downstream reaches. Rates of R, which were much higher than in most temperate streams, also were lower in the headwaters (767 g O2 m−2 y−1) than in the middle and lower reaches (1550–1660 g O2 m−2 y−1). High rates of R and suppressed periphyton abundance caused annual P/R to be \u3c\u3c1 from headwaters to lower reaches. Results for the Rio Mameyes suggest that intense herbivory, which is favored by the presence of large herbivores and consistently high temperatures, may be more typical of tropical than temperate streams. Results also show that the tropical rainforest provides the stream with sufficient amounts of labile organic C to support high rates of respiration over long distances across the basin

Real World Interpretations of Quantum Theory

I propose a new class of interpretations, {\it real world interpretations}, of the quantum theory of closed systems. These interpretations postulate a preferred factorization of Hilbert space and preferred projective measurements on one factor. They give a mathematical characterisation of the different possible worlds arising in an evolving closed quantum system, in which each possible world corresponds to a (generally mixed) evolving quantum state. In a realistic model, the states corresponding to different worlds should be expected to tend towards orthogonality as different possible quasiclassical structures emerge or as measurement-like interactions produce different classical outcomes. However, as the worlds have a precise mathematical definition, real world interpretations need no definition of quasiclassicality, measurement, or other concepts whose imprecision is problematic in other interpretational approaches. It is natural to postulate that precisely one world is chosen randomly, using the natural probability distribution, as the world realised in Nature, and that this world's mathematical characterisation is a complete description of reality.Comment: Minor revisions. To appear in Foundations of Physic

Prospectus, September 23, 1974

ALL SET FOR STUGO ELECTION; Trustees Approve Budget For \u2774-\u2775, Partial Figures On Page 12; 16 Candidates On Ballot For 1st \u2774 Election; PC Counselors Offer More Than Counseling; Attention: Transfer Students; mercy for who?; The Short Circuit; The Kaleidoscope; Letters; Point-Counterpoint: How Do You View America\u27s Future?; Here Are Candidates\u27 Platforms; State House Candidates To Debate Here; Friends; Untitled; Lit. 1.: A Secret Something, Untitled, Rebirth, Everyone\u27s looking for...; \u27DIRT\u27 Comes Off Clean; Really Raunchy Record Review: Eric Clapton, 461 Ocean Boulevard; Meeting For Prospective Debators; Classified Ads; Books: All The President\u27s Men; Republicans To Have Coffee Wednesday; Phi Beta Lambda Meetings Scheduled; APO Chapter Formed Here; In The Dark: That\u27s Entertainment ; Jock Talk; Harriers Perform Well, Abbey Pleased; IM Football Starts Play On 25th; Howell First \u27Fast Freddy\u27; Bowling Bulletin Board; Watching A Counselor At Work; Registration Drive; Cross Country Schedule; Last Chance For Girls IM Football; Fast Freddy\u27s Football Forecast; Callboard; Parkland Events; Summary Of Approved Budget; Vets Elect Officers; A Column By And For Women; Fashion Forecasthttps://spark.parkland.edu/prospectus_1974/1009/thumbnail.jp