Miniature modular microwave end-to-end receiver

An end-to-end microwave receiver system contained in a single miniature hybrid package mounted on a single heatsink is presented. It includes an input end connected to a microwave receiver antenna and an output end which produces a digital count proportional to the amplitude of a signal of a selected microwave frequency band received at the antenna and corresponding to one of the water vapor absorption lines near frequencies of 20 GHz or 30 GHz. The hybrid package is on the order of several centimeters in length and a few centimeters in height and width. The package includes an L-shaped carrier having a base surface, a vertical wall extending up from the base surface and forming a corner therewith, and connection pins extending through the vertical wall. Modular blocks rest on the base surface against the vertical wall and support microwave monolithic integrated circuits on top surfaces thereof connected to the external connection pins. The modular blocks lie end-to-end on the base surface so as to be modularly removable by sliding along the base surface beneath the external connection pins away from the vertical wall

Cost of Producing Feeder Pigs.

4 p

Writing As a Study Skill in the Classroom Learning Spiral

As a cognitive operation, writing is acknowledged to involve the generation of language through assimilation of the known in the form of prior knowledge (Sanacore, 1983). The process also incorporates organizational functions such as categorization in order to create a conceptual flow of information. Further, the act of writing involves a multisensory interaction with language, for it is written, seen and often heard as the writer\u27s thoughts are given permanence in the form of print. Writing is a study skill that teachers can ill afford to neglect in the learning classroom

Cost of Finishing Feeder Pigs.

4 p

Estimating Market Hog Cost--Farrow to Finish.

2 p

Cost of Producing Feeder Pigs.

4 p

Parametric neutronics analyses of lattice geometry and coolant candidates for a soluble-boron-free civil marine SMR core using micro-heterogeneous duplex fuel

Civilian marine reactors face a unique set of design challenges in addition to the usual irradiation and thermal-hydraulic limits affecting all reactors. These include requirements for a small core size, long core lifetime, a 20% cap on fissile loading, and limitations on the use of soluble boron. One way to achieve higher burnup/longer core life is to alter the neutron spectrum by changing the hydrogen-to-heavy-metal ratio, thus increasing the conversion of fertile isotopes in the fuel. In this reactor physics study, we optimize the two-dimensional lattice geometry of a 333 MWth soluble-boron-free marine PWR for 18% 235U enriched micro-heterogeneous ThO2-UO2 duplex fuel and 15% 235U enriched homogeneously mixed all-UO2 fuel. We consider two types of coolant: H2O and mixed 80% D2O + 20% H2O. We aim to observe in which spectrum discharge burnup is maximized in order to improve uranium utilization, while satisfying the constraint on moderator temperature coefficient. It is observed that higher discharge burnup for the candidate fuels is achievable by using either a wetter lattice or a much drier lattice than normal, while epithermal lattices are distinctly inferior performers. The thorium-rich duplex fuel exhibits higher discharge burnup potential than the all-UO2 fuel for all moderation regimes for both coolants. The candidate fuels exhibit higher initial reactivity and discharge burnup with the mixed D2O-H2O coolant than with the H2O coolant in the under-moderated regime, whereas these values are lower for the D2O-H2O coolant in the over-moderated regime

Ultra Wide Band Millimeter Wave Holographic 3-D Imaging of Concealed Targets on Mannequins

Ultra wide band (chirp frequency) millimeter wave “3-D” holography is a unique technique for imaging concealed targets on human subjects with extremely high lateral and depth resolution. Recent “3-D” holographic images of full size mannequins with concealed weapons illustrate the efficacy of this technique for airport security

Development of main-shaft seals for advanced air-breathing propulsion systems Semiannual report, 1 Jul. - 31 Dec. 1966

Deflection and thermal analyses of main shaft seals for advanced air breathing propulsion system