Abstract: A diaphragm valve includes: a valve main body having formed therein a valve chamber, and an inflow passage and an outflow passage being in communication with the valve chamber; an annular valve seat formed in the valve chamber; a diaphragm contacting and separating from the valve seat; and a drive unit driving the diaphragm. The drive unit has a drive unit housing attached to the valve main body so that an outer peripheral edge portion of the diaphragm is sandwiched between the valve main body and the drive unit housing, and the drive unit housing is formed of an electroconductive fluorine resin material.

Abstract: A diaphragm valve includes: a valve main body having formed therein a valve chamber, and an inflow passage and an outflow passage being in communication with the valve chamber; an annular valve seat formed in the valve chamber; a diaphragm contacting and separating from the valve seat; and a drive unit driving the diaphragm. The drive unit has a drive unit housing attached to the valve main body so that an outer peripheral edge portion of the diaphragm is sandwiched between the valve main body and the drive unit housing, and the drive unit housing is formed of an electroconductive fluorine resin material.

Abstract: An ultrasonic flowmeter includes a measurement pipe through which a fluid flows, and two ultrasonic transceivers provided on outer side portions of the measurement pipe so as to be spaced apart from each other in an axis direction. In the method of producing the ultrasonic flowmeter, fabricating the measurement pipe in advance is fabricated, and then is set in a mold as an insert. Two transmitting bodies are formed by insert molding on the outer side portions of the measurement pipe so as to be spaced apart from each other in the axis direction, so that the two transmitting bodies are integral with the measurement pipe. The two ultrasonic transceivers are mounted on the two transmitting bodies, respectively.

Abstract: An ultrasonic flowmeter includes a measurement pipe through which a fluid flows, and two ultrasonic transceivers provided on outer side portions of the measurement pipe so as to be spaced apart from each other in an axis direction. In the method of producing the ultrasonic flowmeter, fabricating the measurement pipe in advance is fabricated, and then is set in a mold as an insert. Two transmitting bodies are formed by insert molding on the outer side portions of the measurement pipe so as to be spaced apart from each other in the axis direction, so that the two transmitting bodies are integral with the measurement pipe. The two ultrasonic transceivers are mounted on the two transmitting bodies, respectively.

Abstract: An ultrasonic flowmeter includes a measurement pipe through which a fluid flows, and two ultrasonic transceivers provided on outer side portions of the measurement pipe so as to be spaced apart from each other in an axis direction. In the method of producing the ultrasonic flowmeter, fabricating the measurement pipe in advance is fabricated, and then is set in a mold as an insert. Two transmitting bodies are formed by insert molding on the outer side portions of the measurement pipe so as to be spaced apart from each other in the axis direction, so that the two transmitting bodies are integral with the measurement pipe. The two ultrasonic transceivers are mounted on the two transmitting bodies, respectively.

Abstract: An ultrasonic flowmeter includes a measurement pipe through which a fluid flows, and two ultrasonic transceivers mounted on two transmitting bodies, respectively. The transmitting bodies are provided on outer side portions of the measurement pipe so as to be spaced from each other in an axis direction, and the measurement pipe and the two transmitting bodies are formed integrally with each other. The measurement pipe has a length, an inner diameter uniform in a length direction, and an arithmetic mean roughness Ra of an inner peripheral surface. The inner diameter is equal to or less than 5 mm, and the length of the measurement pipe is equal to or more than 30 mm. The arithmetic mean roughness Ra satisfies a relation of 0 ?m<Ra?0.2 ?m.

Abstract: In order to avoid large-scale arithmetic circuit and a complicated processing procedure in performing modular arithmetic such as a modular arithmetic exponentiation and modular multiplication in use for encrypting plaintext or the like, the method and apparatus of the present invention for performing the modular arithmetic which executes a first common equation of a modular multiplication arithmetic f(A, B)=A.times.BmodN ("mod" denotes modular arithmetic) to calculate a remainder of a product of an integer A and an integer B divided by an integer N, using a second common equation of Montgomery's replacement arithmetic f(A, B)=A.times.B.times.R'modN corresponding to the first common equation f(A, B)=A.times.BmodN (R' denotes a value to meet the equation R.times.R'modN=1 with respect to R which is an exponent of 2 slightly larger than modulus N), a first replacement arithmetic f.sub.1 '(R.sup.S modN.times.A.sup.T, B.sup.