Switch Box Research Articles

Order of Channels for Safe Routing and Optimal Compaction of Routing Area

For a given placement of blocks and global routing of nets, a new formulation and its solution of the problem of determining the order of channels for the complete channel routing are presented. If the order of channels satisfying the condition exists, it is called the safe order since following it, each channel can be routed the wiring requirement without any prediction of necessary width. Thus the compaction of the routing area can be made utmost each time. The idea is based on the general feature of channel routers not on any particular one. Related subjects such as the simultaneously routable channels, generalization of the safe order, switch box routing, and the placement with nonrectangular blocks are discussed.

A time-shared image-processing system for electron microscopy

A time shared television digital image processing system has been developed for on-line electron microscopy and uses a large mainframe computer (IBM 3033). The system consists of a TV frame store (Grinnell GMR275 full color processor) capable of storing five-512x512x8 bit deep monochrome pictures and four-5 12x512x1 bit graphic overlays. The frame store has many standard features such as: an an 8 bit video digitizer, zoom and pan controls, graphic cursors, image analyzers, arithmetic and boolean processors, alpha numeric generators, lookup tables and so on. A high speed interface has been developed to connect between the host computer and the frame store and can bidirectionally transmit data at 1 Mbit/sec rates over coaxial cable (see Fig. 1). The processor can be controlled from any terminal within the research center. At present a digital switch box has been constructed which will allow up to ten video inputs to be individually assessed from microscopes at remote sites. Also, up to ten full color video ouputs (RGB) from the processor are switchable under computer control.

On the analysis of futile cycles in metabolism

So-called futile cycles in cellular metabolism consist of paired opposing reactions that, if simultaneously operant, act only to degrade free energy of ATP to heat. Previous considerations of the behavior of such substrate cycles have indicated their possible usefulness in regulating flux along metabolic pathways, but such analyses have treated the cycles in isolation, i.e. without taking into account the effects of enzymatic inputs to and outputs from the cycle. We here develop models of three typical substrate cycles that include enzymatic inputs to and outputs from the cycle and allow the enzymes of the cycles per se to be subject to a variety of allosteric modulations. The non-linear equations which describe these models were solved by an iterative procedure for sets of parameter values of metabolic interest. The results, when analyzed using appropriate definitions of regulatory sensitivity and energetic futility, demonstrate that the effects of the enzymes leading into and out of the cycle may cause profound changes in the operation of the substrate cycle and therefore may not be ignored. We find that the structural differences among the three cycles considered here result in corresponding functional differences. Our results suggest that (1) the fructose-6-P/fructose-1,6-di-P cycle acts effectively to gate bidirectional flux, but doesn't appreciably enhance regulation of unidirectional flux, (2) the glucose/glucose-6-P cycle is well suited to perform a homeostatic function and to adjust the set points for these two metabolites, and (3) the cycle at the pyruvate crossroads functions largely as a complex switch box that directs metabolic flow towards gluconeogenesis or glycolysis not only in response to inputs of or requirements for oxaloacetate, pyruvate, and phosphoenolpyruvate, but also in response to the combined action of allosteric modulators on the individual enzymes of this substrate cycle.

A device for silent on-line recording of continuously changing behavioral measures

A nonintrusive method of monitoring continuously changing behavior frequently is required in experimentation with human subjects, particularly infants. The touch-sensor switch box provides the observer with an ongoing record on a polygraph and allows the observer to give undivided attention to the subject. The mode of operation is completely silent.

Temperature Control

Temperatures of perishable dairy products in 30 Oregon retail food stores were determined systematically with the aid of a quick response electronic thermometer. Sensitive thermistor surface probes permitted measurement of product temperatures from the exterior surfaces of two adjacent containers to within 0.5 F. A switch box facilitated the simultaneous use of up to six probes for measuring product, air blower, and air “curtain” temperatures at various cabinet shelf locations. Fluid milk temperatures for the outside rows of shelves averaged 4.5 F higher than the inside rows of product. The average temperatures for products in refrigerated display cases were: fluid milk and cream, 43.9 F; cottage cheese, 46.4 F; and hard cheese, 48.8 F. More than 35% of all products checked exceeded the Oregon maximum legal temperature of 45 F and 75% of the products exceeded the generally accepted optimum storage temperature of 40 F. The data indicate a definite need for improvement in temperature control of refrigerated display cases used for perishable dairy products. A form was designed to simplify and efficiently record temperature data for retail food stores.

Experiments in electrostimulation as a therapy for sensori-neural hearing loss

Since 1969, experiments have been conducted by various laboratories to evaluate an electrostimulation device offered commercially as a therapy for sensorineural hearing loss. The device manufactured by Intelectron Corporation passes an amplitude modulated high-frequency carrier current through a subject's head by means of an array of four electrodes worn in the manner of a set of headphones. The therapy requires electrostimulation for approximately one hour per day, five days per week for a period of six weeks to produce an improvement in speech discrimination. Groups receiving active electrostimulation have been compared with control groups receiving simulated treatment. Results have been quite variable among the laboratories and have led to considerable controversy as to the effectiveness of the therapy. The success of the therapy achieved by the Pennsylvania State University and the UCLA Medical Center has allowed these experiments to continue and has shed much light on the procedures required to produce the greatest improvements. A recent experiment at Penn State involving tests of evoked responses and middle ear reflex measured before and after therapy produced some unexpected results. The improvements obtained in speech discrimination in this most recent experiment were so marginal that an investigation was launched into the effects of the placebo switch box on the therapy current. These findings to be presented help explain the success or failure of previous experiments and provide information needed to improve the efficiency of the therapy.

Real Time Animation Of Architectural MobileElements

A computer program designed to provide movement in real time has been developed including aspects such as changing the point of view, transforming the model, variation of colours and stereoscopic vision, all this controlled simultaneously from a switch box with as many functions as desired. In this paper some applications are shown with general aspects of the

Pharmacologically Induced Resistance to Heat Shock: 3. Effects of Rauwolfoids and Chlorpromazine on Heart Rate

OBSERVATIONS on the protective action of three tranquilizing drugs—the rauwolfoids reserpine and reserpine-free mother liquor, and chlorpromazine—against death from exposure to a standardized experimental acute thermal stressor (Burger and Lorenz, 1960a) led to observations suggesting that a reduction in reactivity of the sympathetic nervous system is important (Burger and Lorenz, 1960b). Since heart rate reflects (however imperfectly) the activity of the sympathetic system, a series of experiments was undertaken attempting to relate heart rates to treatment with two of these drugs and to conditions of heat shock.MATERIALS AND METHODSFor the experiments an electrocardiotachometer was constructed: Each lead was a flexible shielded cable (grid-lead wire) terminated at one end with a phono pin plug. At the other end the active lead was terminated with two 2-inch safety pins, and the indifferent lead with one. The leads were connected to a switch box with 48 input positions; the …

Studies with radioiodine. IV. Collimating cones for crystal counters.

In a clinical radioiodine laboratory it is important frequently to determine the frontal area of a thyroid gland as a guide to its size, and to find out whether or not an area of the body or abnormal mass such as a metastatic thyroid tumor or a brain tumor contains I131 in excess of that in the surrounding tissue. If such a mass does exist, it is then important to record the fact of its existence and to establish its size, shape, position, and radioiodine content. Unshielded and partially shielded collimated Geiger and scintillation counters, either held by hand or by some kind of scanning rack, have been used for these purposes by most workers in the field of radioactivity. Uncollimated scintillation counters have a high sensitivity to gamma rays but have poor “localizing ability” at any appreciable distance. It is possible, by limiting the acceptance angle of the crystal for radiation through the use of a collimating cone, to gain a higher order of “localizing ability,” at the expense of sensitivity. Single-channel collimators with small apertures have the disadvantage of using only a small portion of the crystal and therefore are of low sensitivity. In addition, the sensitivity of the counter falls off as the distance between the radioactive source and crystal is increased. Better “localizing ability,” greater sensitivity of the counter with distance, and the use of as much as one-half of the crystal can all be achieved by the use of multichannel collimators. The theoretical background for the design of multichannel collimators was presented by Newell, Saunders, and Miller. Consideration of the problems involved led to the fabrication and study of various types of collimators. The effective use of collimating devices demands that there be a satisfactory apparatus for moving the counter and collimator over the area in which the radioactivity is to be measured and that there be apparatus to record properly the position of the counter and the radiation which falls on it. This paper presents a description of such an apparatus and the results of studies with different collimators. Apparatus Figure 1, a photograph of the apparatus, shows a counter assembly mounted on a scanning rack, which in turn is mounted on an x-ray tube stand. The counter is connected to two scalers arranged in series. The lower scaler contains a counting rate meter; its responses are measured and recorded on the Speedomax recorder. The switch box on the top of the upper scaler permits the simultaneous starting of the recorder chart and the moving of the counter. The counter assembly (Fig. 2) comprises a crystal scintillation counter, lead shield, collimator, and lead filter (0.5 gm.∕cm.2).