Abstract: A polycentric reamer having a body thrust unit and reaming unit is especially useful for locally reaming a borehole beneath a casing string. By asymmetrically positioning a reaming unit within a body formed from non-coaxial mated cylinders, superior results are achieved. These results include minimizing wear on the casing string.

Abstract: Ecologically safe constructional materials, and particularly large-sized constructional structures such as wall plates can be economically produced. Wood or another vegetable material ground to the particle size of not more than 2.times.10.sup.-3 m, dried to 9-11% moisture content, heated by heating the press-mold to the 200.degree. to 220.degree. C. temperature and adding ground material heated at least 120.degree. C., and loaded it into the press-mold for 1 to 1.5 min. per 1.times.10.sup.-3 m of produced pressed material. After that, pressing is done in a hermeticly sealed press-mold at this temperature at a pressure of not less than 30.0 MPa with exposure to this pressure for 1 to 1.5 min. per each 1.times.10.sup.-3 m of produced pressed material followed by cooling of press-mold without depressurization at full pressure.

Abstract: Multiple-hull catamaran vessels equipped with hydrofoils have two hulls connected by a deck. Transverse to the hulls below the waterline are three or more hydrofoils, the trim bow and stern hydrofoils, and the relieving middle hydrofoil or a group of hydrofoils. The bow and stern hydrofoils are mounted at a distance not less than 30% and 20% of the hull length to the bow and stern, respectively, from the center of mass. Lift arising on all hydrofoils when sailing at a maximum calculated speed in calm sea reaches 60-70% and in calculated rough seas 20-40% of the catamaran's full weight. The bow foil, middle and stern foils account for 0.05-0.15; 0.15-0.30; 0.10-0.25 shares of the catamaran's full weight, respectively. When sailing in rough sea and during vertical travels of the hulls (vertical rocking), "submergence--emergence" takes place which leads to "increase--decrease" of the lift thereby reducing vertical travel amplitude.

Abstract: A method for producing machined parts with curvilinear profiles allows for selection of the optimum rotational frequency of a part to be machined by analyzing wave process energy created by interaction of the machining instrument and the machined part while creating the curvilinear profile. During preliminary machining at several rotational frequencies, integral values of the wave process energy are determined and the relationship between these values and the rotational frequencies are identified. The optimum rotational frequency is then selected according to the minimum value of the aforementioned relationship. Increased accuracy in selecting the proper rotational frequency reduces wear of the machining (or cutting) instrument and produces higher quality machined parts in a reduced amount of time.