Decision Support Systems in Australian Agriculture: State of the Art and Future Development

This paper reports and discusses the results of a survey conducted with experts working in the field of decision support systems (DSS) in Australian agriculture. It also reviews the literature on DSS in the light of these experts' responses. The findings from this survey have consolidated our understanding of the current state of DSS in Australian agriculture. The uptake of DSS by farmers has been slow and various issues said to be contributing to this include fear of using computers, time constraints, poor marketing, complexity, lack of local relevance, lack of end-user involvement, and mismatched objectives between developers and users. The future prospect for the development of DSS was generally regarded to be poor. Never-the-less, the authors believe that new DSS which embrace the suggested criteria could be widely accepted by farmers. These criteria mean that to be widely used by farmers, any successful DSS needs to address widespread problems: they need to be location specific, and gain strong support from initial users. They also need to be simple to use, relevant, effective, low cost, and user friendly and it is most likely that farmers would have been involved in their development. We believe that farmers' personalities, and their attitudes towards risk management and decision making, will influence the pattern of adoption of DSS in Australian agriculture while the intergenerational change that is occurring in the management of Australian farms is a positive factor that may encourage more widespread use of these tools.DSS, farmers' decision-making, expert opinion, management decisions, Farm Management, D7, D8, Q12, Q13, Q16,

Prompt Beta Spectroscopy as a Diagnostic for Mix in Ignited NIF Capsules

The National Ignition Facility (NIF) technology is designed to drive deuterium-tritium (DT) internal confinement fusion (ICF) targets to ignition using indirect radiation from laser beam energy captured in a hohlraum. Hydrodynamical instabilities at interfaces in the ICF capsule leading to mix between the DT fue l and the ablator shell material are of fundamental physical interest and can affect the performance characteristics of the capsule. In this Letter we describe new radiochemical diagnostics for mix processes in ICF capsules with plastic or Be (0.9%Cu) ablator shells. Reactions of high-energy tritons with shell material produce high-energy $\beta$-emitters. We show that mix between the DT fuel and the shell material enhances high-energy prompt beta emission from these reactions by more than an order of magnitude over that expected in the absence of mix

Treatment of Metal Wastes Containing Ni, Co and Mn with Deep-Sea Manganese Nodules

The spent Ni-Cd battery and the spent catalyst containing cobalt were treated by reductionsmelting process with deep-sea Manganese nodules for recovery of nickel and cobalt metals. The nickel in the spent Ni-Cd battery could be recovered with adding 5% coke as a reducing agent regardless of the amount of battery added. However, to recover cobalt from the spent catalyst, it is required to add more coke for reduction of cobalt oxide in the catalyst. The treatment of metal wastes with manganese nodules can contribute to lower the cost for the proce-ssing of nodules and to facilitate the recycling of metal wastes

Memory and superposition in a spin glass

Non-equilibrium dynamics in a Ag(Mn) spin glass are investigated by measurements of the temperature dependence of the remanent magnetisation. Using specific cooling protocols before recording the thermo- or isothermal remanent magnetisations on re-heating, it is found that the measured curves effectively disclose non-equilibrium spin glass characteristics such as ageing and memory phenomena as well as an extended validity of the superposition principle for the relaxation. The usefulness of this "simple" dc-method is discussed, as well as its applicability to other disordered magnetic systems.Comment: REVTeX style; 8 pages, 4 figure

Inverse velocity statistics in two dimensional turbulence

We present a numerical study of two-dimensional turbulent flows in the enstrophy cascade regime, with different large-scale forcings and energy sinks. In particular, we study the statistics of more-than-differentiable velocity fluctuations by means of two recently introduced sets of statistical estimators, namely {\it inverse statistics} and {\it second order differences}. We show that the 2D turbulent velocity field, $\bm u$, cannot be simply characterized by its spectrum behavior, $E(k) \propto k^{-\alpha}$. There exists a whole set of exponents associated to the non-trivial smooth fluctuations of the velocity field at all scales. We also present a numerical investigation of the temporal properties of $\bm u$ measured in different spatial locations.Comment: 9 pages, 12 figure

Risk Management Strategies by Australian Farmers

Australian farmers operate in one of the most risky environment in the world. They have to cope with various sources of risk in their businesses. This paper reports results of two case studies undertaken to examine the issues of farming risks and risk management strategies in Australia. The first case study found that climate variability, financial risk, marketing risk, and personal risk were regarded as the major sources of farming risk in the Upper Eyre Peninsula of South Australia. The main management strategies used by farmers included diversifying varieties, minimising tillage, minimising area of risky crops and maximising area of the least-risky crop, having high equity, having farm management deposits and other off-farm investments, and "leaving marketing to experts". The second case study revealed that climate variability was ranked as the most important source of farming risk in southwest Queensland. This was then followed by financial risks, government policy, and marketing risks. The main management strategies used were enterprise diversification (having predominantly cattle and farming cash crops), conserving moisture, using zero till planting, diversified sales (selling only part of the farm's production at any one time), and having off-farm investments. The paper then attempts to reconcile the two case studies by comparing the results with studies from the United States of America, Canada, Netherlands, and New Zealand.risk, risk management, strategies, farmers, Australia, Farm Management, Risk and Uncertainty,

Automated Dynamic Headspace/GC-MS Analyses Affects the Repeatability of Volatiles in Irradiated Turkey

The amounts of dimethyl disulfide and dimethyl trisulfide decreased as sample holding time in an autosampler (4 °C) before purge increased, whereas those of aldehdyes increased as holding time increased due to lipid oxidation. Helium flush of sample vials before sample loading on an autosampler retarded lipid oxidation and minimized the changes of sulfur volatiles in raw meat, but was not enough to prevent oxidative changes in cooked meat. Although DH/GC-MS is a powerful method for automatic analysis of volatiles in meat samples, the number of samples that can be loaded in an autosampler at a time should be limited within the range that can permit reasonable repeatabilities for target volatile compounds

Volatile Sulfur Compounds in Foods as a Result of Ionizing Radiation

Ionizing radiation improves food safety and extends shelf life by inactivating food-borne pathogens and spoilage microorganisms. However, irradiation may induce the development of an off-odor, particularly at high doses. The off-odor has been called “irradiation odor”. Substantial evidence suggests that volatile sulfur compounds (VSCs) play an important role in the development of the off-odor. These compounds include hydrogen sulfide, methanethiol, methyl sulfide, dimethyl disulfide and dimethyl trisulfide among others. The formation of off-odor and VSCs due to irradiation in meat, and fruit juices is presented. It is known that irradiation exerts its effect through radiolysis of water in foods where water is a dominant component. Irradiation of water produces three primary free radicals: hydroxyl, hydrogen atoms, and hydrated electrons. Use of specific scavengers in a model system revealed that hydroxyl radicals are involved in the formation of VSCs. Possible mechanisms for formation of VSC are also discussed. Also discussed are possible remedies for formation of VSCs and off-odor, such as use of antioxidants and double packaging

Volatile Production of Irradiated Normal, PSE, and DFD Pork

With both aerobic and vacuum packaging, irradiation increased the production of sulfur-containing volatiles in all three pork types (normal, PSE, DFD) at day 0, but did not increase hexanal - the major indicator volatile of lipid oxidation. PSE pork produced the lowest amount of total sulfur-containing volatiles in both aerobically and vacuum-packaged pork at day 0. Majority of sulfurcontaining volatiles produced in meat by irradiation evaporated during the 10-day storage period under aerobic packaging conditions. With vacuum packaging, however, the all the volatiles produced by irradiation remained in the packaging bag during storage. Irradiation had no relationship with lipid oxidation-related volatiles (e.g., hexanal) in both aerobic and vacuum-packaged raw pork. DFD muscle was very stable and resistant to oxidative changes in both irradiated and nonirradiated pork during storage, suggesting that irradiation can significantly increase the use of raw DFD pork and greatly benefit pork industry

Quality Characteristics of Vacuum-Packaged, Irradiated Normal, PSE, and DFD Pork

Irradiation increased the redness of vacuum-packaged pork loins regardless of meat type. Irradiation and storage time had no effect on the 2-thiobarbituric acid reactive substances (TBARS) values of normal, PSE and DFD pork. Irradiation increased the production of sulfur (S)-containing volatile compounds and total volatiles in all three pork types. Normal pork had more values of total and S-containing volatile compounds on irradiation than the PSE and DFD pork. The volatiles produced by irradiation remained in the packaging bag during storage. The odor acceptance of the three meat types was not different, but panelists could distinguish irradiated meat from the nonirradiated. Irradiation and storage of meat in vacuum packaging may be desirable for long-term storage, but may reduce the acceptance of irradiated meat. Double packaging—individual packaging of meat with oxygen permeable film and repackaging multiple individual packages in large vacuum-packaging bags for irradiation and storage—and opening the outside vacuum packaging bag 1–2 days before sale, is recommended to reduce irradiation odor