Simulation of growth and development of diverse legume species in APSIM

This paper describes the physiological basis and validation of a generic legume model as it applies to 4 species: chickpea (Cicer arietinum L.), mungbean (Vigna radiata (L.) Wilczek), peanut (Arachis hypogaeaL.), and lucerne (Medicago sativa L.). For each species, the key physiological parameters were derived from the literature and our own experimentation. The model was tested on an independent set of experiments, predominantly from the tropics and subtropics of Australia, varying in cultivar, sowing date, water regime (irrigated or dryland), row spacing, and plant population density. The model is an attempt to simulate crop growth and development with satisfactory comprehensiveness, without the necessity of defining a large number of parameters. A generic approach was adopted in recognition of the common underlying physiology and simulation approaches for many legume species. Simulation of grain yield explained 77, 81, and 70% of the variance (RMSD = 31, 98, and 46 g/m2) for mungbean (n = 40, observed mean = 123 g/m2), peanut (n = 30, 421 g/m2), and chickpea (n = 31, 196 g/m2), respectively. Biomass at maturity was simulated less accurately, explaining 64, 76, and 71% of the variance (RMSD = 134, 236, and 125 g/m2) for mungbean, peanut, and chickpea, respectively. RMSD for biomass in lucerne (n = 24) was 85 g/m2 with an R2 of 0.55. Simulation accuracy is similar to that achieved by single-crop models and suggests that the generic approach offers promise for simulating diverse legume species without loss of accuracy or physiological rigour

Industrial Field Trials of Oregon Graduate Institute-Developed Electroslag Welding Technology

DTFH61-86-X-00119The primary objective of this program was to demonstrate that the Oregon Graduate Institute (OGI)-developed electroslag welding (ESW) technology cay be successfully implemented in commercial fabrication shops. Consequently, opportunity was provided to evaluate the transferability of ESW technology and to develop additional ESW mechanical property data from commercially fabricated weldments

Repair of Process-Related Defects in Electroslag Welding

DTFH61-86-X-00119The primary objectives of this program were to develop a welding procedure for repair of electroslag weldments and to determine if repair welding influenced the fatigue strength of electroslag weldments. Integral to this effort was the identification of the most likely types of defects, their causes, and the potential for effective repair. The electroslag welding (ESW) process is capable of producing a higher volume of defect-free weld deposit than other processes used for joining structural steel. When defects do occur, however, ESW is not well-suited for use as a repair process since it is limited to vertical position, single-pass, full-thickness welding