Photovoltaic power system tests on an 8-kilowatt single-phase line-commutated inverter

Efficiency and power factor were measured as functions of solar array voltage and current. The effects of input shunt capacitance and series inductance were determined. Tests were conducted from 15 to 75 percent of the 8 kW rated inverter input power. Measured efficiencies ranged from 76 percent to 88 percent at about 50 percent of rated inverter input power. Power factor ranged from 36 percent to 72 percent

System tests with electric thruster beam and accelerator directly powered from laboratory solar arrays

Laboratory high voltage solar arrays were operated directly connected to power the beam and accelerator loads of an 8-centimeter ion thruster. The beam array comprised conventional 2 by 2 centimeter solar cells; the accelerator array comprised multiple junction edge-illuminated solar cells. Conventional laboratory power supplies powered the thruster's other loads. Tests were made to evaluate thruster performance and to investigate possible electrical interactions between the solar arrays and the thruster. Thruster performance was the same as with conventional laboratory beam and accelerator power supplies. Most of the thruster beam short circuits that occurred during solar array operation were cleared spontaneously without automatic or manual intervention. No spontaneous clearing occurred during conventional power supply operation

Bit error rate testing of a proof-of-concept model baseband processor

Bit-error-rate tests were performed on a proof-of-concept baseband processor. The BBP, which operates at an intermediate frequency in the C-Band, demodulates, demultiplexes, routes, remultiplexes, and remodulates digital message segments received from one ground station for retransmission to another. Test methods are discussed and test results are compared with the Contractor's test results

Longshoreman-Shipowner-Stevedore: The Circle of Liability

It is universally recognized that in the past two decades the United States Supreme Court has substantially revised the law under which seamen, longshoremen and harbor workers (or their survivors) may recover damages for personal injury and death. One of the more recent and most authoritative texts in the field of admiralty and maritime law devotes an entire chapter, 147 pages in length, to the subject of the rights of seamen and maritime workers (or their survivors) of recovery for injury and death. The introduction to that chapter likens the Court\u27s rewriting of the law in this field to a volcano and states that as long as it continues in eruption, no charts can be guaranteed reliable as to its future course. It must be conceded that one of the more recent, major and most astounding eruptions is that pertaining to the rights of longshoremen to recover damages for personal injuries sustained in the course of their employment aboard vessels. Since World War II the spotlight of judicial decision and review in maritime cases has been focused upon this one narrow field until it has become one of the most litigious in this country. It is the purpose of this article to review the background and history of events within that field, set forth clearly and concisely the status of the law and note some changes which may be forthcoming

Studies of three millets and three Sudan grasses as supplemental summer pasture

Supplemental summer pastures are in great demand by many Tennessee farmers who raise dairy or beef cattle. Little data are available, however, to aid these farmers in selecting the best varieties of grasses or legumes to serve this purpose. Specifically, information is lacking on the two new varieties of Sudan grass, Sorghum vulgare var. Sudanese, which only recently have been introduced. These new varieties need to be compared as to palatability and yields with other crops that are now serving the farmer as a supplemental summer pasture

Collisions at infinity in hyperbolic manifolds

For a complete, finite volume real hyperbolic n-manifold M, we investigate the map between homology of the cusps of M and the homology of $M$. Our main result provides a proof of a result required in a recent paper of Frigerio, Lafont, and Sisto