Photovoltaic power modules for NASA's manned space station

The capability and the safety of manned spacecraft are largely dependent upon reliable electric power systems. Two similar space power systems able to survive the low Earth orbit environment, are being considered for NASA's Manned Space Station (SS), scheduled to begin operation in the mid 1990's. The Space Station Electric Power System (EPS) is composed of Photovoltaic (PV) Power Modules, Solar Dynamic (SD) Power Modules, and the Power Management and Distribution (PMAD) System. One EPS configuration will deliver 37.5 kW of PV based, utility grade, ac power to SS users. A second 75 kWe PV based EPS option is also being considered for SS deployment. The two EPS options utilize common modules and differ only in the total number of PV Power Modules used. Each PV Power Module supplies 18.75 kWe of ac power and incorporates its own energy storage and thermal control. The general requirements and the current preliminary design configuration of the Space Station PV Power Modules are examined

The Mathematics of Cancer: Fitting the Gompertz Equation to Tumor Growth

Mathematical models are finding increased use in biology, and partuculary in the field of cancer research. In relation to cancer, systems of differential equations have been proven to model tumor growth for many types of cancer while taking into account one or many features of tumor growth. One feature of tumor growth that models must take into account is that tumors do not grow exponentially. One model that embodies this feature is the Gomperts Model of Cell Growth. By fitting this model to long-term breast cancer study data, this project ascertains gompertzian parameters that can be used to predicts tumor growth as a function of time

Braun v. Soldier of Fortune: Tort Law Enters the Braun\u27s Age As Constitutional Safeguards for Commercial Speech Buckle \u27neath the Crunch of Third-Party Liability

Advertising is more than just a substantial source of revenue for publications. This author contends that advertising embodies the liberties of free speech and free press secured to all of us so fundamentally by the First Amendment. This Casenote analyzes Braun v. Soldier of Fortune Magazine, Inc., in which the Eleventh Circuit held a magazine liable for negligently publishing a gun-for-hire advertisement that allegedly resulted in the death of the plaintiff\u27s father. The author is critical of this decision, noting the detrimental, long-reaching effects of sustaining a negligence action that penetrates so deeply into First Amendment freedoms

The effects of aerobic training on basal metabolic rate

The purpose of this study was to investigate the effects of aerobic exercise training on the basal metabolic rate (BMR) of untrained individuals. [This is an excerpt from the abstract. For the complete abstract, please see the document.

Space Station Photovoltaic Power Modules

Silicon cell Photovoltaic (PV) power modules are key components of the Space Station Electrical Power System (EPS) scheduled to begin deployment in 1994. Four PV power modules, providing 75 kWe of user ac power, form the cornerstone of the EPS; which is comprised of Photovoltaic (PV) power modules, Solar Dynamic (SD) power modules, and the Power Management and Distribution (PMAD) system. The PV modules are located on rotating outboard sections of the Space Station (SS) structure and each module incorporates its own nickel-hydrogen energy storage batteries, its own thermal control system, and some autonomous control features. The PV modules are a cost-effective and technologically mature approach for providing reliable SS electrical power and are a solid base for EPS growth, which is expected to reach 300 kWe by the end of the Space Station\u27s 30 year design lifetime