Abstract: Lubricant base oils are made up essentially of 2-15% by weight of a total aromatics content, greater than 60% by weight of isoparaffins and monocyclic naphthenes in total, more than 30% by weight of alkylbenzenes in the total aromatics content and smaller than 4% by weight of tricyclic and tetracyclic aromatics in the total aromatics content. The base oil has great viscosity index, small pour point, high oxidative stability and heat stability and sufficient capability to dissolve sludge.

Abstract: A photographic camera has a rectilinear approximate operation circuit for calculating characteristic correction data for correcting errors in the operational characteristics of the camera. Predetermined theoretical characteristic data dependent on operational characteristics of the camera are stored. Measured data corresponding to predetermined measured values are stored as individually measured characteristic data in a nonvolatile EEPROM so that the stored measured data can be easily changed by rewriting the EEPROM. An object signal is generated depending on an object to be photographed. The rectilinear approximate operational circuit calculates characteristic correction data from the object signal, the theoretical characteristic data and the measured characteristic data, which is then used for correcting errors in the operation characteristics of the camera.

Abstract: An automatic playing device has a memory which stores sequence data consisting of musical sound data and sequence data to control read-out of the musical sound data. A processing unit repeatedly reads out musical sound data specified by the control data included in the sequence data stored in the memory. A movement instruction switch gives instructions for movement of an accompaniment part to be played. A control device terminates, when an instruction for movement of a part to be played is issued by the movement instruction switch, the operation to repeatedly read out musical sound data if musical sound data stored in the memory is being repeatedly read out by the processing unit. In this case, the control device moves system operation to read out the next sequence data.

Abstract: A gradient index optical element for use in optical lens such as a camera or microscope is disclosed. The optical element comprises at least one of first metal dopants selected from La, Zr, Sn, In, Y, Ge, Zn, Ba, Ca, As, Sr, Ga and Gd distributed in solvent with a slope, and at least one of second metal dopants selected from Nb, Ta, Ti, Bi, Pb, Sb, Zr, Sn, In, Y and Tl, which is distributed equally in the solvent so as to satisfy following equation as absolute amount;.vertline..DELTA.C.sub.f /.DELTA.C.sub.g .vertline..multidot.100.ltoreq.5wherein .DELTA.C.sub.g is a difference between maximum value and minimum value of equivalent value of metal oxides of the first metal doping and .DELTA.C.sub.f is a difference between maximum value and minimum value of equivalent value of metal oxides of the second metal doping.

Abstract: An electronic apparatus which is equipped with an ultrasonic motor and which consumes only a small amount of electric power, is stable in performance, and is capable of accurately controlling the angular position is offered.A driving pulse storage circuit stores driving pulses corresponding to the environment of the components of the ultrasonic motor. A stopping pulse storage circuit stores stopping pulses corresponding to the environment of the components of the motor. An environment detection means detects the environment of the components. An output pulse-selecting circuit receives the output signal from a driving pulse-generating circuit and the output signal from a stopping pulse-generating circuit and produces output pulses corresponding to the output signal from a detection signal-generating circuit to a piezoelectric vibrator-driving circuit. The moving member and the output means are operated by ultrasonic vibration of the vibrating member.

Abstract: A fuel injection type multiple cylinder engine unit includes an oil lubricating device including an oil tank and the oil in the oil tank is pumped up by a pump having an oil drain side to which pipes are connected for supplying the oil near the injectors. Each of the pipe has a front nozzle portion disposed at a portion near the front fuel jetting end of the injector and the fuel and the oil independently injected in an intake device of the engine unit are atomized and mixed with suitable mixture ratio. The intake device of the engine unit is provided with a surge tank which comprises a main surge tank formed integrally with an inlet manifold and sub-surge tanks formed by forming recesses between the respective adjacent intake pipes in association with the inlet manifold. The main surge tank and the sub-surge tanks are communicated with each other to thereby increase the total inner volume of the surge tank.