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In this article, a cutting forces model for micro flat end milling is developed by regarding tool run-out or eccentric and tilt deviation of tool path as well as the effect of bottom edge cutting. ...

Megathrust earthquakes tend to be confined to fault areas locked in the interseismic period and often rupture them only partially. For example, during the 2015 M7.8 Gorkha earthquake, Nepal, a slip pulse propagating along strike unzipped the bottom edge of the locked portion of the Main Himalayan Thrust (MHT). The lower edge of the rupture produced dominant high-frequency (>1 Hz) radiation of seismic waves. We show that similar partial ruptures occur spontaneously in a simple dynamic model of earthquake sequences. The fault is governed by standard laboratory-based rate-and-state friction with the aging law and contains one homogenous velocity-weakening (VW) region embedded in a velocity-strengthening (VS) area. Our simulations incorporate inertial wave-mediated effects during seismic ruptures (they are thus fully dynamic) and account for all phases of the seismic cycle in a self-consistent way. Earthquakes nucleate at the edge of the VW area and partial ruptures tend to stay confined within this zone of higher prestress, producing pulse-like ruptures that propagate along strike. The amplitude of the high-frequency sources is enhanced in the zone of higher, heterogeneous stress at the edge of the VW area.

For a toroid-shaped end-milling cutter to have multi-structure features of tooth offset center and introversion of bottom edge, this article proposes a generalized parametric modeling method of the bottom edge, including a straight edge segment and a circular arc edge segment. And based on the parametric model, this article also deduces the corresponding tool path for grinding of the bottom edge’s rake and flank faces. The parametric modeling method is based on the geometric analytic equations while the grinding method is driven by the proposed parametric model and the parameters of rake and flank faces. The two methods can be applied to a bottom edge of a cutter with multi-structure features to guarantee G1 continuity at the two joints for connecting a circular arc edge with a straight edge and a conical helix edge, respectively. In order to verify the accuracy of proposed methods, experiments were carried out. The modeling and grinding experimental results verified the accuracy and utility of the methods.

Requirements stated in regulatory documents are discussed with respect to determining deformations in beds of vertical steel cylindrical tanks used to store oil and oil products. A procedure is proposed for determining tilt in the foundation and the tank proper, based on the aggregate settlement of deformation markings on the foundation and points along the bottom edge. A computer program was developed to calculate tilt. An example is presented of determining settlement and tilt for a pile foundation of a vertical steel tank after 5 years of operation.

This papyrus fragment is coarse, stained, and abraded, with writing on the recto only, if it is the recto, across the fibers. The bottom edge is irregularly torn, the top edge somewhat so, but, except perhaps for its heading, the full text of the original seems to be preserved, and the original edges seem to be preserved in sections at right and left. The writing is fluent, confident, and well spaced.

This papyrus piece is light brown and coarse, with edges neatly cut at top, bottom, and left; the right edge is shredded, but it appears that no more than a few letters have been lost there: See below, line 4. Writing appears on the recto only, across the fibers; the bottom edge has been cut just 0.3 cm. below a collesis, confirming that the papyrus page was turned on edge prior to use. The writing, dark and rather thick, is confident and well-spaced (lines at 0.9 cm. intervals; some three letters to a centimeter), but with erratic flourishes which are sometimes problematical.

An apparatus for sealing an automatic elevator door against sound closes the small air gaps between a door post and a door leaf rear edge, between an abutment and the door leaf top edge, between abutting front edges of door leaves, between an inner door leaf front edge and outer door leaf rear edge in the case of telescopic doors, and between a door sill and a door leaf bottom edge. A post seal utilizes an elastic strip seal to close the post air gap. An abutment seal utilizes a sliding brush seal to close the abutment air gap. A door sill seal utilizes a labyrinth seal to close the sill air gap. A door edge seal utilizes a brush seal to close the front edge air gap. These seals close all the air gaps around the door leaves when the door is closed to prevent the ingress of sound of the noises produced mechanically outside the car.

Geodetic observations made before and after the 1987 March 2 Edgecumbe earthquake have been inverted to deduce for that event the parameters of a rectangular dislocation model with uniform slip. Despite the effects on the vertical data of near-surface compaction during shaking. and ground damage, the results are consistent with geological and seismic information. Solutions can be found for all parameters of the unconstrained problem, but to maintain agreement with geological observations, the strike can be constrained at 055°. The remaining parameters are then estimated as: normal dip-slip = 2. 7 ± 0. 4 m (with insignificant strike-slip), dip = 39 ± 3° to the nonhwest, length = 13 ± 1 km, depth to top edge = 0. 6 ± 0. 2 km, depth to bottom edge = 6. 4 ± 1. 0 km. The inferred moment is 8. 5 × 1018 N m corresponding to a moment magnitude of 6. 6.

To enable a bricklayer to construct an arch over an opening in the wall of a building, the carpenter must provide him with a support on which he can lay his bricks to shape the arch. This support can be either a solid piece of timber cut to the shape of the bottom edge of the arch (figure 7.1) — which is called a turning piece — or a timber frame as shown in figure 7.2, which is called a center. The height of an arch and the thickness of the wall will dictate whether a turning piece or a center is to be provided. Usually, turning pieces are used only for fairly low segmental arches and for flat arches.

A microphone mount and plug mount for attaching to the side of a motorcyclist's helmet, said microphone mount adapted to secure a microphone boom positioning a microphone proximate the motorcyclist's mouth, the motorcycle mount characterized by a clamp portion adapted to forcefully engage the bottom edge of the helmet with minimum structure below the edge of the helmet, and a boom seat to receive the boom base and passage of electrical wires from the microphone mount. The plug mount defines a clamp portion similarly adapted to surround the lower edge of the helmet, and a plug seat defining a cavity adapted to receive a electrical plug and an opening to said plug seat cavity to receive electrical wires from said microphone mount and from a headset mounted interiorly to said helmet, the electrical plug receiving a mating electrical plug attached to wires connecting with audio accessories located on said motorcycle.

Escapes from conventional box traps, especially by previously captured animals, prompted development of an improved trap to catch woodchucks (Marmota monax). A comparison of trapping periods with improved and conventional traps showed a marked increase in the number of woodchucks captured with the improved trap, as well as an increase in the proportion of previously marked animals held. J. WILDL. MANAGE. 39(2):439-442 Although improvements in traps frequently are mentioned, data to support the contention rarely are presented. This paper describes some changes in design and presents data showing increased efficiency. A 1955-70 study of the woodchuck population on Letterkenny Army Depot, Chambersburg, Pennsylvania, required the use of live traps to capture the animals. Early in the project, woodchucks were trapped with box traps similar to those described by Mosby (1955) and Taber and Cowan (1969:284). The trap had a wooden treadle to which was fastened a heavy gauge wire supporting the door which fell from the inside when the treadle was depressed. It became evident that these traps were not efficient in holding woodchucks. The tendency of woodchucks to escape was greater for those with previous trap experience than for those captured for the first time. Woodchucks escaped by one of two means: (1) reaching in past the treadle for the bait while balancing the door on their backs, and then backing out, or (2) turning around and lifting the door with a front foot. A slight nick or hole in the bottom edge of the door provided a toehold for woodchucks to lift the door. If the bottom edge of the door fitted tightly, a few minutes of chewing provided the necessary hold. Trump and Hendrickson (1943) stated that woodchucks pushed on such a door but did not pull on it. MATERIALS AND METHODS The trap (Fig. 1) length was increased to 36 inches to prevent woodchucks from stealing the bait without being captured. A transom catch was used as a latch to sto animals from lifting the door from inside. Driving three nails through the top of the trap near the back end and addition of a metal lining to the inside of the door thwarted animals' attempts to chew out of traps. In addition, the triggering mechanism was improved and simplified by using a wooden post rather than wire. The post makes the trap easier to construct, easier to set, harder to trip accidentally, and easier to repair. The following materials were used: 2 pcs., 36 x 1 x 8-inch pine, top and bottom; 2 pcs., 36 x 1 x 10-inch pine, sides; 1 pc., 18 x 1 x 7-inch pine, treadle; 1 pc., 10 x 1 x 7-inch pine, door; 1 pc., 6 x 2 x 2-inch pine, treadle post; 1 pc., 8.5 x 7-inch aluminum "valley tin" or heavy sheet aluminum, door lining; 1, 10 x 9-inch piece of 1 x 2-inch welded wire, back end; 1, reversible transom catch; 4, 2-inch-#7 flat-head wood screws; 30, 0.75-inch wire staples; 21, 8d box nails; and 24, 0.75-inch 16 gauge nails. SStudy supported by National Institutes of Health (Grant HE12295). J. Wildl. Manage. 39(2):1975 439 This content downloaded from 157.55.39.17 on Fri, 02 Sep 2016 05:28:14 UTC All use subject to http://about.jstor.org/terms 440 AN IMPROVED WOODCHUCK TRAP Ludwig and Davis

A bulldozer having a transversely elongate cutter blade closely spaced from the bottom edge of the mold board is disclosed. The cutter blade is mounted for reciprocal motion in forward and aft directions relative to the mold board. Unidirectional force impulses are applied to the cutter blade in a forward direction to drive the blade intermittently forward without aft motion. Preferably, the unidirectional force impulses are applied by first and second matched force transmitting beams. Each beam has two divergent approximately straight legs that meet at a juncture to form an acute, approximately 90° angle, a node at the juncture, an input anti-node at the end of one leg, and an output anti-node at the end of the other leg at the input frequency. A source of vibrations at or near the resonant frequency is coupled to the input anti-node and the output anti-node is disposed in spaced aft relationship from the cutter blade within striking distance thereof. The beams are mounted adjacent to the rear surface of the mold board so the mold board extends into the space between the legs with the input anti-node disposed near the top of the mold board and the output anti-node disposed near the bottom of the mold board.

A mechanism for automatically blocking the gap between the bottom edge of a door leaf, hung to open and close within a surrounding frame, and the adjacent threshold, when the door is closed; and automatically unblocking that gap when the door starts to open again, comprises an elongate bar housed above a strip of material in the bottom edge region of the door leaf. The bar and strip of material each are coupled to respective attraction/repulsion elements. One element is a magnet and the other is a piece of material having a positive reaction to a magnet, typically a further magnet. One end of the bar or an auxiliary member coupled to the bar protrudes from an edge of the door adjacent the door frame. The arrangement is such that, with the door open, the strip of material is raised clear of the adjacent threshold. As the door closes, the protruding end of the bar or auxiliary member contacts the upright of the door frame and is moved longitudinally to take the two sets of magnets out of line with one another and to allow - or to positively repulse - the strip of material to fall and block the gap between the bottom edge of the door leaf and the adjacent threshold.