The stress analysis of pressurized circumferential pipe weldments under steady state creep is considered. The creep response of the material is governed by Norton’s law. Numerical and analytical solutions are obtained by means of perturbation method, the unperturbed solution corresponds to the stress field in a homogeneous pipe. The correction terms are treated as stresses defined with the help...

A study was conducted to document the physical environment and growth performance of nursery pigs in hoop structures compared with pigs reared in confinement nurseries. A series of six trials involving a total of 1,440 nursery pigs were conducted at two Iowa State University research farms from December 1999 to August 2000. Regardless of season, the confinement pigs grew faster and consumed mor...

Background. A theoretical model analysis of stress in the vestibular membranes has identified a geometrical stress factor incorporating shape, size, and thickness that can be used to assess peak stress in the various chambers. Methods. Using published measurements of the toadfish vestibular membranes made during surgery, the geometrical stress factor can be evaluated for each chamber based on t...

shrink fit process is a useful technique in order to introduce beneficial residual stress in compound pressure vessels. in this paper, the effects of geometrical tolerances on residual stresses have been studied for a compound shrink fitted pressure vessel, practically. three layers, which are designed based on an optimum nominal thickness and overlap dimensions and tolerances, have been fitted...

The objective of this review paper is to document extensive bedded indoor and outdoor pig production in the United States, which has expanded due to growing niche markets for natural and organic pork. Bedded hoop (tentlike) barns are used for finishing pigs and gestating sows. Seasonal outdoor farrowing and some indoor bedded farrowing systems coupled with group lactation are used also. Most na...

ion of Models of Stress Corrosion Cracking of Drip Shield and Waste Package Outer Barrier and Hydrogen Induced Corrosion of Drip Shield TABLE OF CONTENTS Page 1. PU R P O SE ............................................................................................................................... 8 2. QUALITY ASSURANCE .............................................. 8 3. COMPUTER SOFTWARE AN...

and Implications Four groups of early weaned pigs (19 days of age) from the ISU Southwest Swine Research Farm, Atlantic, IA were delivered to the Hoop Research Complex at the ISU Rhodes Research Farm, Rhodes, IA, in late May and early June 1998. Three groups of pigs (n=552) were placed in three (30–ft × 60 ft) deep bedded hoop structures. The fourth group (n=159) was placed in a mechanically ve...

We report the result of comparison between two reaction coordinates [on the potential energy surface of the first excited state (S(1))] produced by CASSCF and these energies recalculated by MRMP2 in the Z to E photoisomerization of penta-2,4-dieniminium (PDI) as the minimal model of the retinal protonated Schiff base (RPSB). One coordinate is the S(1) state minimum-energy-path (MEP) in mass-wei...

This paper presents main results of a shale stability study, related to the understanding of shale/ fluid interaction mechanisms, and discusses shale strength correlation. The major shale/ fluid interaction mechanisms: Capillary, osmosis, hydraulic, swelling and pressure diffusion, and recent experimental results are discussed. Factors affecting the shale strength are discussed, and a sonic com...