The Production of Food and Fiber: An Adaptation of CoP Features for Sustainable Water Use in Agribusiness

Citation: Harris, K. D., & James, H. S. (2016). The Production of Food and Fiber: An Adaptation of CoP Features for Sustainable Water Use in Agribusiness. Sustainability, 8(11), 15. doi:10.3390/su8111189Fresh water and arable land are essential for agricultural production and food processing. However, managing conflicting demands over water and land can be challenging for business leaders, environmentalists and other stakeholders. This paper characterizes these challenges as wicked problems. Wicked problems are ill-formed, fuzzy, and messy, because they involve many clients and decisions makers with conflicting values. They are also not solvable, but rather must be managed. How can agribusiness leaders effectively manage wicked problems, especially if they have little practice in doing so? This paper argues that a Community of Practice (CoP) and its tripartite elements of domain, community and practice can be effective in helping businesses manage wicked problems by focusing on the positive links between environmental stewardship and economic performance. Empirically, the paper examines three agribusinesses to assess the extent in which CoP is used as a strategy for sustainable water management

An examination of transaction interdependency: a perspective in the animal health and nutrition industrial system

The research examining bioscience networks has been studied from two perspectives. One view comes from economics and the other sociology. We examine the technical (material flows) and people aspects (information sharing) of interdependency in the context of economic exchanges in a bioscience network. The empirical contributions are the techniques used to explain the network structure of a burgeoning animal health and nutrition bioscience network and the portability of network analysis concepts that provides the potential to manage diverse business networks. The results suggest the economic exchanges can be traced back to the underlying interactions that safeguard transactions and influence the flow of resources and information

An evaluation of the pressure proof test concept for thin sheet 2024-T3

The concept of pressure proof testing of fuselage structures with fatigue cracks to insure structural integrity was evaluated from a fracture mechanics viewpoint. A generic analytical and experimental investigation was conducted on uniaxially loaded flat panels with crack configurations and stress levels typical of longitudinal lap splice joints in commercial transport aircraft fuselages. The results revealed that the remaining fatigue life after a proof test was longer than that without the proof test because of crack growth retardation due to increased crack closure. However, based on a crack length that is slightly less than the critical value at the maximum proof test stress, the minimum assured life or proof test interval must be no more than 550 pressure cycles for a 1.33 proof factor and 1530 pressure cycles for a 1.5 proof factor to prevent in-flight failures

Cryogenic mechanical loss of a single-crystalline GaP coating layer for precision measurement applications

The first direct observations of gravitational waves have been made by the Advanced LIGO detectors. However, the quest to improve the sensitivities of these detectors remains, and epitaxially grown single-crystal coatings show considerable promise as alternatives to the ion-beam sputtered amorphous mirror coatings typically used in these detectors and other such precision optical measurements. The mechanical loss of a 1 μm thick single-crystalline gallium phosphide (GaP) coating, incorporating a buffer layer region necessary for the growth of high quality epitaxial coatings, has been investigated over a broad range of frequencies and with fine temperature resolution. It is shown that at 20 K the mechanical loss of GaP is a factor of 40 less than an undoped tantala film heat-treated to 600 °C and is comparable to the loss of a multilayer GaP/AlGaP coating. This is shown to translate into possible reductions in coating thermal noise of a factor of 2 at 120 K and 5 at 20 K over the current best IBS coatings (alternating stacks of silica and titania-doped tantala). There is also evidence of a thermally activated dissipation process between 50 and 70 K

Screw and Pin Fastener Tests for Cold-Formed Steel

Because of limited available information on strength and ease of installation of specific fasteners for a particular application to a steel deck diaphragm, a preliminary testing program comparing the shear strength of commercially available screws and gas-actuated shot pins was conducted by J. R. Harris and Company at the University of Colorado Denver in 2018. A test was designed to explore the behavior and capacity of various fasteners, securing two and three pieces of sheet steel of various thicknesses together. Specimens were fabricated and load tested, with the sheet steel pieces in tension, so the fasteners were subject to shear. Four fasteners, in two rows of two, were used for all tests, with different end distances also being studied. Most of the tests were monotonic tension, and those results were used to develop a cyclic testing protocol for the best performing screw and shot pin. Most limit states encountered were limited by tilting of the screw against the sheet steel in bearing, leading to a ductile failure. Fastener shear was encountered in a small percentage of cases. Results are compared to each other and to AISI calculated values

An investigation of the sensitivity of the Fermi surface to the treatment of exchange and correlation

The Group V and VI transition metals share a common Fermi surface feature of hole ellipsoids at the N point in the Brillouin zone. In clear contrast to the other Fermi surface sheets, which are purely of d character, these arise from a band that has a significant proportion of p character. By performing local density approximation (LDA), generalized gradient approximation (GGA), strongly constrained and appropriately normed (SCAN) meta-GGA, and GW approximation calculations, we find that the p character part of this band (and therefore the Fermi surface) is particularly sensitive to the exchange-correlation approximation. LDA and GGA calculations inadequately describe this feature, predicting N hole ellipsoid sizes that are consistently too large in comparison to various experimental measurements, whereas quasiparticle self-consistent GW calculations predict a size that is slightly too small (and non-self-consistent GW calculations that use an LDA starting point predict a size that is much too small). Overall, for the metals tested here, SCAN provides the most accurate Fermi surface predictions, mostly correcting the discrepancies between measurements and calculations that were observed when LDA calculations were used. However, none of the tested exchange-correlation approximations succeeds in simultaneously bringing all of the measurable properties of these metals into good experimental agreement, particularly where magnetism is concerned. The SCAN calculations predict antiferromagnetic moments for Cr that are 3 times larger than the experimental value (1.90 $\mu_B$ compared to 0.62 $\mu_B$)