Abstract: A pivot pin bearing/seal especially adapted for supporting the rotor of a disposable filtration cartridge of a continuous-flow plasmapheresis blood separation system includes a lubricious plastic pivot pin injection molded with a recess at its end. The recess is surrounded by a sharp circular inside edge. A stainless steel eyelet, deep drawn from successive dies, is loosely inserted into the pin recess, a radial outer surface defined at the junction between the eyelet shank and the eyelet flange contacting the pin sharp edge. The eyelet rotates relative to the pin, the circular line path of rotational contact being defined by the smooth curved surface under the flange of the eyelet and the sharp inside edge surrounding the pin recess which quickly burnishes to a good rotational seal.

Abstract: A blood constituent processing system uses a disposable plastic fluid flow path into which an anticoagulant must be accurately metered with respect to pumped blood flow. In a preliminary calibration phase, a closed fluid flow path is provided between the anticoagulant pump and the blood pump. One of the pumps is then controlled to inject fluid into such closed path while the other pump is controlled to withdraw fluid from that path at what is nominally an equal fluid flow rate. Changes in fluid pressure within the closed fluid flow path are then monitored and the flow rate of at least one of the pumps is changed as necessary to achieve an approximately constant fluid pressure within the closed fluid flow path. The relative pump flow control required to achieve constant pressure may then be taken as a relative flow rate calibration between the two pumps so as to permit subsequent accurate pumped metering of anticoagulant into the pumped blood flow.

Abstract: An improved blind signature system not requiring computation during blinding for anticipating which of a plurality of possible signatures will be made during signing, while still allowing the blinding party to unblind and recover the unanticipated kind of signature on what was blinded. An exemplary embodiment blinds by forming a product including a plurality of generators raised to powers normally secret from the signing party, and unblinds by forming a product with the multiplicative inverse of a signed form of the generators raised to the original powers. Re-blinding allows a signature on a value to be transformed into a signature on a particular blinded form of the value.

Abstract: A cryptographic system allows, in one exemplary use, a supplier to cryptographically transform a plurality of messages responsive to secret keys; the transformed messages to be digitally signed by a signer; and the signed transformed messages returned to the supplier to be transformed by the supplier, responsive to the same secret keys, in such a way that a digital signature related to each original message is developed by the supplier. One important property of these systems is that the signer cannot determine which transformed message received for signing corresponds with which digital signature--even though the signer knows that such a correspondence must exist.

Abstract: In a multi-slice magnetic resonance imaging system which employs a train of plural RF NMR nutation pulses, the frequency spectrum and/or magnetic gradient employed for succesive pulses is controlled so as to effect more nearly equal full-width-half-magnitude (FWHM) or other spatial dimensions of actual nuclei nutation variation versus distance curves for all of the slice selective nutation pulses. The result is a reduction of any "gap" of non-imaged volume disposed between the succession of selected MRI slice volumes.

Abstract: A control system providing control from multiple control consoles of a circuit board fabricated device. Indicators at each control console provide users with status information so that users will not command conflicting functions of the device. The control system uses a control circuit arrangement that minimizes the number of printed wires and terminal connectors on a standardized back plane circuit board used in conjunction with the circuit board fabricated device.

Abstract: In a communication system wherein multiple radio stations communicate with one another over a single channel, an arrangement for indicating to a first user who is transmitting over the channel that there is a simultaneous transmission occurring on the channel by another user, possibly blocking or interferring with transmission by the first user. The arrangement includes means for periodically causing the transmitting first radio station to reduce its transmitting power, listen for a simultaneous transmission on the channel by another station, and then resume full transmitting power. The detection of a simultaneous transmission is annunciated to alert the first user that his transmissions may have been interferred with. Interruption of the first user's transmission may occur either periodically or at detected pauses between the first user's spoken words. The arrangement operates in conjunction with the conventional automatic gain control circuit of the first user's station.

Abstract: Cup-type impellers are utilized on wind energy machines which are driven according to a first embodiment to rotate about a vertical axis and according to a second embodiment to rotate about a horizontal axis. In the vertical axis embodiment, the shaft driven by the cups is coupled to one or more offset generators by a gear. Preferably, a single generator mounted to rotate about a vertical axis is utilized. The rotor of the generator is supported by a low friction vertical bearing. In a second embodiment, a pair of cone supports is utilized to drive a horizontally disposed shaft. The shaft is oriented normally with respect to wind direction by utilizing a wind vane mounted on a separate support which detects wind direction and transmits information regarding wind direction to a platform supporting the drive shaft. Preferably, the generator is mounted directly on the drive shaft.

Abstract: A calculating device and a method of use thereof for determining the lead required to shoot a projectile at a moving target including cooperating logarithmic scales with indicia corresponding to the parameters target speed, range, projectile speed and lead displayed on a fixed and a slide member. Pictorial markers representative of various projectiles are disposed along the projectile velocity scale at locations corresponding to their normal speed and words descriptive of target speed are disposed at appropriate locations along the target speed scale so that calculations may be made by persons not having knowledge of game and projectile speeds in numerical terms. In accordance with one embodiment of the invention, the logarithmic scales are longitudinally disposed and the slide member may move relative to the fixed member in a horizontal direction. In accordance with other embodiments of the invention, the scales are disposed in a circular arc on members which may be rotated about a common axis.

Abstract: A computer power/temperature protector is provided. A control and disconnect circuit is responsive to a power interruption to disconnect power from a computer to which the protector unit is connected in-line, and thereafter responsive to a reset signal to connect power to the computer. A power interruption is obtained automatically when a voltage failure occurs on the power cable to the computer. A thermostatic switch also automatically interrupts power when the ambient temperature of the room in which the computer or other load is located exceeds an adjustable pre-set level. A power emergency disconnect switch is provided for manually interrupting power. Furthermore, the present invention provides at least one varistor for shunting transient voltages. The varistors are automatically connected to the power lines of the cable when the apparatus is manually reset to supply power to the computer.

Abstract: A monitor for monitoring the performance of a digital transmission system has three level sensors for sensing at decision instants the level of a signal derived from a transmitted signal. A first of the level sensors has its threshold set at a level corresponding substantially to the eye diagram amplitude, a second has its threshold set near the upper level of the eye diagram amplitude, and the third has its threshold set near the lower level of the eye diagram amplitude. The outputs from the level sensors are connected to logic circuitry which is arranged to energize an alarm whenever the upper or lower eye amplitude level is between the thresholds of the second and third level sensors.

Abstract: Separate electrical timing and load activation devices are provided for each of plural electrical loads and each device is connected to receive reference timing signals from a central unit. Each of the separate timing and load activation devices measures a reference time interval accurately defined by the reference timing signals and subsequently activates its associated electrical load after a respectively corresponding predetermined time delay which is determined as a function of the locally measured reference time interval.

Abstract: A data processing unit including means for reducing original data or producing the data in coded form and for recording the same on photographic or magnetic media e.g. photographic film or disc or magnetic tape, scanning means for sensing the data recorded on the record media to produce electrical signals indicative of the reduced or coded data and means including decoding means where the original data is coded and responsive to the signals from the scanning means for reproducing the data on a static visual reading device e.g. an electrophoretic memory unit, in a legible form recognizable by a reader. The decoding means is responsive to address data signals from the scanning means to produce output signals indicative of the coded data in decoded form.

Abstract: The availability of service in a telephone exchange is evaluated by a technique which includes monitoring for each call type over a period of time the level of usage of the items of equipment required for that call type and evaluating using the monitored data the probability of each particular item not being able to provide a service when required. The probability figures of the call types can be combined to give an index figure indicative of the availability of service of the exchange.

Abstract: Densities of resonant nuclei within elemental volumes along a line are measured using the nuclear magnetic resonance phenomenon called "spin echo". A first planar volume of nuclei is selectively excited to nutate spins by approximately 90.degree.. Thereafter a second planar volume of nuclei, transverse to the first planar volume, is selectively excited to nutate spins by approximately 180.degree.. The nuclei in the line volume common to both of the planar volumes thereafter generate characteristic spin echo signals. A magnetic gradient is established along this line volume during the spin echo read out so that the resultant spin echo signals can be processed to determine the respective densities of resonant nuclei along the line volume. Appropriate phasing of the excitations enables interference with the spin echo signals by the free induction decay to be eliminated. To enable rapid development, successive line volumes are read out which do not lie in previously excited planes.

Abstract: A filter network that exhibits a bandstop response comprises a network of basically low pass or high pass structure. The network is developed by choosing a bandstop transfer function, a fourth-orderelliptic is disclosed, which is converted to a low pass function. This function describes a passive low pass LC ladder network including a negative impedance element. A Bruton transformation is applied to the passive LC network to give an active version including an ungrounded negative resistance network in a series arm and frequency-dependent negative resistances in shunt arms without requiring inductance coils for its implementation.

Abstract: A calculating device and a method of use thereof for determining the lead required to shoot a projectile at a moving target such as game including cooperating logarithmic scales with parameter indicia corresponding to the range of the target, the speed and direction of movement of the target, the speed of the projectile and the required lead displayed on a fixed and a slide member. Markers representative of various projectiles are disposed on the projectile velocity scale at locations corresponding to their normal speed and words descriptive of game speed are disposed at appropriate locations along the target speed scale so that calculations may be made by persons not having knowledge of game and projectile speeds in numerical terms. The lead is calculated from a knowledge of the parameters in a two step process of moving one member relative to the other. In accordance with one embodiment of the invention, the scales are arcuately disposed on members which may be rotated about a common axis.

Abstract: A generally toric lighter-than-air gas bag-type airfoil is tethered to the ground at a plurality of angularly widely distributed points about the periphery of the gas bag. A wind turbine is mounted at the entrance to the axially central vent. The tether lines are entrained about individually operable power winches, preferably controlled by a microprocessor which takes in wind direction and tether line tension data and operates the winches and inflation gas inlet and outlet valves to orient the wind turbine into the wind for maximum power output.

Abstract: Milling apparatus wherein material to be milled is agitated with a charge of particulate material also includes one or more predispersing chambers through which the material to be milled enters the apparatus. The chamber includes pumping means which carry out predispersing work.

Abstract: A method for use under program control in a digital computer for automatically evaluating compiler level language logic condition sets and for compiling machine executable instructions directly therefrom is disclosed. More specifically, a unique method of constructing an array of novel logical linkages is described which permits an especially rapid direct compilation of an efficient and optimum-sized set of machine executable instructions without constructing the usual logic decision tables or going through an extra assembly level language step as is the case with most prior compilers. Rather, the method described generates an array of so-called primary link codes representing logical interrelationships or links between successive source deck cards in a condition set while also generating an associated array of so-called secondary link codes representing logical interrelationships or links between successive entries on the same source deck card in a condition set.