Elliptical Opening Research Articles

Effect of the heat flux on brittle fracture near an elliptical opening

Effect of the heat flux on brittle fracture near an elliptical opening

Concentration of deformations around openings in a glass-fiber plastic due to pulse loading

The data on the deformation concentrations around circular and elliptic openings in fabric glass-fiber plastic in the case of pulse loading, presented in the article, show that Kɛ is a function of the ratio between pulse length and opening dimensions, as well as of the orientation of the material structure with respect to the direction of the load. The results obtained correspond to the commensurability between pulse length and opening dimensions. Experiments on cylindrical panels made of wound glass-fiber plastic have resulted in a test procedure for curvilinear surfaces. The values of Kɛ presented indicate an additional effect of the surface curvature on the deformation concentration.

Spreading of cracks from the contours of elliptical openings in brittle plates under biaxial tensile stresses

Spreading of cracks from the contours of elliptical openings in brittle plates under biaxial tensile stresses

Effect of eccentric reinforcement of the edge of an opening in an anisotropic plate on the state of stress

A general mathematical approach is proposed to the solution of problems of the elastic equilibrium of anisotropic plates with a nonsymmetrically reinforced edge. This approach is based on the representation of the boundary conditions of the problem in the form of contour integrals containing an arbitrary function holomorphic in the region of the plate. Diagrams characterizing the dependence of the stresses in an orthotropic plate with an elliptic opening on the eccentricity of the reinforcement are presented.

Determination of the deformed state of an elasticoplastic thick plate with an elliptical opening

Determination of the deformed state of an elasticoplastic thick plate with an elliptical opening

Elastic equilibrium of the weight anisotropy of a half-plane with an elliptical opening

Elastic equilibrium of the weight anisotropy of a half-plane with an elliptical opening

Distribution of stresses close to an elliptic opening in a plate made of fibrous materials

Distribution of stresses close to an elliptic opening in a plate made of fibrous materials

Stress state of a plate with strong anisotropy weakened by two elliptical openings

Stress state of a plate with strong anisotropy weakened by two elliptical openings

THE STRUCTURE, FUNCTION, AND POSTEMBRYONIC DEVELOPMENT OF THE MALE AND FEMALE COPULATORY ORGANS OF THE BLACK WIDOW SPIDER LATRODECTUS CURACAVIENSIS (MÜLLER)

A comparison of the structure of the male and female pedipalpi shows that the patella, tibia, tarsus, and the pretarsus of the male are modified. The tarsus in the male is represented by a spoon-shaped cymbium, and the pretarsus by a complex, copulatory palpal organ. This organ in the mature male is a "more specialized" type with an internal receptaculum seminis guarded by the subtegulum, tegulum, median apophysis, radix, terminal apophysis, conductor, and the embolus. The walls of the fundus and the reservoir are of uniform thickness, containing numerous pores on the side facing the gland cells. The ectodistal tooth of the cymbium fits into the socket of the median apophysis, the embolic tip rests on the conductor, and the embolic base is hooked to the basal tooth of the radix. A trigger-like mechanism of extension of the palpal organ is described.The palpal organ arises from the hypodermal cells of the claw fundament. A longitudinal invagination in the ventral lobe of the fundament forms the receptaculum seminis and the dorsal lobes form the accessory sclerites. After transformation of its fundament, the new claw loses connection with the muscle tendons and is short and simple. There is no correlation between the teeth of the claw and the sclerites of the organ.The female copulatory organs consist of paired, dumb-bell-shaped spermathecae; coiled sac-like bursae copulatrices; small, straight fertilization tubes; and blind canals. Ventrally the apparatus is covered by a heavily sclerotized epigynum with an elliptical opening into the atrium which contains the outer openings of the bursae copulatrices. The embolus penetrates the bursa to bring its tip partly within the spermatheca where the broken embolic fragment is later found.The female apparatus arises as a pair of double invaginations of the body wall within the epigastric furrow, immediately ventrad of the opening of the uterus. In successive stages, gradual development of the tissue brings the invaginations outside the epigastric furrow. The two pockets of the invaginations increase in size, the dorsal ones developing into the spermathecae and the ventral ones into the bursae copulatrices.

Research at the Colorado School of Mines in subjects related to the mechanics of rock failure

The paper presents the results of experiments at Colorado School of Mines in subjects related to the mechanics of rock failure. A brief review of Fenner's hypothesis of the distribution of stress around circular and elliptical openings is presented and field evidence cited which supports the hypothesis.An impact loading device useful in studies of rock failure is described, and the attitudes of strain lines in a brittle, lacquer‐coated tunnel model as obtained with the impact loading device are compared with the directions and magnitudes of the principal stresses obtained using an interferometer. The distribution of the strain lines is compared with the stress distribution around the opening, and a strain pattern produced by impact loading is compared with one produced by static loading. Results indicate that the apparatus and techniques can be used to determine the direction of principal stress and to compare static and impact loads producing similar strain patterns.

On a Foramen in the Lower Extremity of the Humerus

DURING flexion of the forearm the coronoid fossa of the humerus receives the coronoid process of the ulna. On the posterior surface above the trochlea is a deep triangular depression, the olecranon fossa, in which the summit of the olecranon is received in extension of the forearm. These two fossae are separated from one another by a thin, more or less transparent lamina of bone, lined in the fresh state by the synovial membrane of the elbow joint.1 The plate of bone separating the coronoid and the olecranon fossae may be perforated. This opening is called the supratrochlear foramen.2 It is a more or less oval or elliptical opening with a smooth margin and sloping edges with the long axis transverse, about 5 to 9 mm. wide and 3 to 4 mm. high. It is located above the epiphyseal line and is in the intra-articular part of the olecranon fossa below the line of reflection of the synovial membrane which crosses the middle of the fossa. When large, the hole is actually in an open state; when small, it may be cover...

AN IMPROVED DELIVERY SHEET

This sheet was devised in an endeavor to develop a delivery drape that would permit the patient a moderate amount of freedom of motion without seriously disturbing delivery room technic. Sack-like leggings are sewed directly to elliptical openings in a sheet made of any heavy material, such as Indian Head. The central portion is reinforced with an extra thickness of the same material. Two tapes are sewed on the under side below the opening in the central section. All seams are double stitched. When it is desired to drape the patient, the limbs are thrust into the leggings, and the central aperture is arranged over the vulva. The assisting nurse then pins the attached tapes to the patient's gown, so that the lower portion of the reinforced area is tucked under the buttocks, and holds the drape closely to the vulva. Added security of arrangement may be obtained by the