Methods and systems of the present invention may be used to recognize digital image data arranged in rows and columns. The sensors are particularly useful in safety control circuits for heating members using PTC wire as resistance heating elements. 2 nm to 10 nm on a surface of the hole portion by a physical vapor deposition method; forming an electroless plating layer on the surface of the hole portion by an electroless plating method using the catalyst layer as a catalyst; and burying up the hole portion with an electrolytic plating layer by an electrolytic plating method using the electroless plating layer as a seed layer. The disclosure teaches a means of providing the control of data flow to multi-port simultaneous access memory systems, utilizing the control paths in the memory control systems rather than the data paths in such systems. When the primer assembly is assembled, the tubular body encloses the primer head assembly and the primer head assembly seals the internal chamber. The synchronizing ring comprises axial grooves distributed on the tapered internal bore, each groove extending over a surface corresponding to at least three consecutive axial teeth, two successive grooves being separated by at least ten axial teeth.