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This paper reports fracture assessments of large-scale straight pipes and elbows of various pipe diameters and crack sizes. The assessments estimate the load for ductile fracture initiation using the failure assessment diagram method. Recent solutions in the literature for stress intensity factor and limit load provide the analysis inputs. An assessment of constraint effects is also performed using recent solutions for elastic T-stress. It is found that predictions of initiation load are close to the experimental values for straight pipes under pure bending. For elbows, there is generally increased conservatism in the sense that the experimental loads are greater than those predicted. The effects of constraint are found not to be a major contributor to the initiation fracture assessments but may have some influence on the ductile crack extension.

Background:Pes cavus is a progressive and ugly deformity of the foot. Although initially the deformity is painless, with time, painful callosities develop under metatarsal heads and arthritis supervenes later in feet. Mild deformities can be treated with corrective shoes, or foot exercises. However, in others, operative treatment is imperative. Soft tissue operations are largely unsatisfactory and temporary. Bony operations give permanent correction. We present our series of 18 patients of pes cavus in the adolescent age group, treated by Japas' V-osteotomy of the tarsus.Materials and Methods:18 patients of paralytic pes cavus deformity were treated by Japas osteotomy, between March 1995 and 2005, at our institute. The age of the patients ranged from 8.6 to 15 years (mean 11.3); 10 were boys and 8 girls. All cases had unilateral involvement, and all, but one, were post-polio cases.Result:The mean follow-up is 5.4 years. Of the 18 patients, 14 had excellent or good corrections; 4 had poor correction/complications. However, those patients could be salvaged by triple arthordesis or Dwyer's calcaneal osteotomy.Conclusion:Japas' osteotomy is a satisfactory option for correction of pes cavus deformity in adolescents. In patients who have rigid hind foot equinus or varus, however, the results are compromised.

A B S T R A C T Specimen J-R curve is extensively used for structural integrity of large components. It is well known that J-R curve heavily depends on constraint level ahead of crack tip in remaining ligament. In earlier work, it was demonstrated that J-R curve from Three Point Bending (TPB) specimen is transferable to straight pipe with circumferential through wall crack. In this paper, the transferability of J-R curve is investigated from TPB specimen to pipe with circumferential surface crack. A 16 in. diameter pipe with circumferential surface crack and TPB specimen machined from same piping material (SA333Gr6 Steel) are tested. Consequently, 3D finite element analysis (FEA) has been performed on surface cracked pipe and TPB specimen. Crack-initiation load is also predicted for surface cracked pipe by FEA and compared with experimental result. J-R curve is calculated for the pipe using experimental data, that is, load, load line displacement and crack growth. J-R curve of pipe is compared with TPB specimen and it is found that the pipe is predicting much higher J-R curve than TPB. This difference of J-R curve is investigated by evaluating stress triaxiality in remaining ligament for both cases. Stress triaxiality is quantified using triaxiality factor (h) ahead of crack tip for pipe and TPB specimen. It is found that the TPB specimen has considerably higher constraint level than pipe with surface crack, which is well supported by trend of J-R curves for specimen and pipe. A study has also been carried out to investigate the effect of internal pressure on the stress triaxiality. It is found that there is negligible difference in stress triaxiality because of internal pressure. The stress triaxiality is re-established as a qualitative parameter to assess the transferability of J-R curve from specimen to component. a = initial crack size A 2 = A 2 -stress (valid for large strain region) c = half crack length D 0 = outer diameter of pipe E = Young's modulus h = stress triaxiality factor J e = J-elastic J i = crack initiation toughness J p = J-plastic k = stiffness K = stress intensity factor p = internal pressure Correspondence: M. K. Sahu.

Malware classification and detection process is a very complex process in network security. In current network security scenario various types of malware family are available, some are known family and some are unknown family. The family of knowing malware detection used some well know technique such as signature based technique and rule based technique. In case of an unknown malware family of attack detection is various challenging tasks. In the current trend of malware detection used some data mining technique such as classification and clustering. The process of classification improves the process of detection of malware. In this paper used graph based technique for malware classification and detection. The graph based technique used for a feature collection of different malware data. The proposed algorithm is very efficient in compression of pervious method.