A-LSSVM: an Adaline based iterative sparse LS-SVM classifier

A threaded tube extends through the hull of a boat well above the water line. An outer, baffled, vent cap with a threaded inner tubular portion is screwed onto the outer end of the threaded tube. The vent cap also includes an outer tubular portion concentric to and spaced from the inner tubular portion; both being held in place by a solid outer cap. A first breather opening through the upper part of the inner tubular portion, next to the solid cap, connects the inside of the threaded tube to the space between the inner and outer tubular portions, and a second breather opening through the lower part of the outer tubular portion connects the space between the inner and outer tubular portions to the outer air. A threaded nut near the inner end of the threaded tube tightens against the inside of the hull to draw the outer vent cap tightly against the outside of the hull. A tube may be used to connect the inner end of the threaded tube to any desired tank.