提高尾矿设施的工作效率

本文叙述了卡奇卡纳尔采选公司与科研，设计单位合作开展科研工作，提高尾矿设施工作效率的经验。     

Voting among virtually generated versions of a classification problem

A classifier combining strategy, virtual voting by random projection (VVRP), is presented. VVRP takes advantage from the bounded distortion incurred by random projection in order to improve accuracies of stable classifiers like discriminant analysis (DA) where existing classifier combining strategies are known to be failed. It uses the distortion to virtually generate different training sets from the total available training samples in a way that does not have the potential for overfitting. Then, a majority voting combines the base learners trained on these versions of the original problem. VVRP is very simple and just needs determining a proper dimensionality for the versions, an often very easy task. It is shown to be stable in a very large region of the hyperplane constructed by the dimensionality and the number of the versions. VVRP improves the best state-of-the-art DA algorithms in both small and large sample size problems in various classification fields.     

Automatic anatomically selective image enhancement in digital chest radiography

A technique for automatic anatomically selective enhancement of digital chest radiographs is developed. Anatomically selective enhancement is motivated by the desire to simultaneously meet the different enhancement requirements of the lung field and the mediastinum. A recent peak detection algorithm and a set of rules are applied to the image histogram to determine automatically a gray-level threshold between the lung field and mediastinum. The gray-level threshold facilitates anatomically selective gray-scale modification and/or unsharp masking. Further, in an attempt to suppress possible white-band or black-band artifacts due to unsharp masking at sharp edges, local contrast adaptively is incorporated into anatomically selective unsharp masking by designing an anatomy-selective emphasis parameter which varies asymmetrically with positive and negative values of the local image contrast     

Portability of three consumer products

Three consumer products (a television set, a personal computer and a typewriter), all considered portable by their respective manufacturers, were evaluated experimentally for portability. Products were not considered portable if the physical and subjective workloads resulting from carrying them over specified distances were excessive. Twenty-two males and six females participated in the experimental investigation and carried the three products for distances of 45·72, 91·44. 137·16 and 182·88 m. Their pulse and ratings of perceived exertion (RPE) of the arms and whole body were recorded and used as measures of physical and perceived workloads. Both physiological and subjective responses to carrying products were significantly influenced by the type of product and carrying distance, regardless of the gender of the person performing the carrying. The results of this study and the design guidelines provided in the literature for one-handed and two-handed carrying tasks led to the conclusion that, of the three products, only the television set could be considered portable.     

Catalysts of lipid oxidation in meat products

In emulsions consisting of refined lard, egg white and corn starch haemoglobin, initially a mixture of the oxy and met forms, at levels similar to the haemoprotein contents found in fresh meat, was a far more powerful catalyst of lipid oxidation, as measured by TBA number, than inorganic iron compounds at levels appropriate to those found in meat. This was true over the pH range 4·5 to 7·5. When added and evenly distributed to exhaustively washed muscle fibres (WF), at levels appropriate to those found in meat, haemoglobin was again a powerful catalyst, but all forms of inorganic iron appeared to have little prooxidant activity. The rate of oxidation of the lipid was very dependent on the haemoprotein concentration, being maximal in the range 10(-4) to 10(-5) M. This equates to an approximate unsaturated lipid to haem molar ratio of several hundred to one, similar to the values reported for model linoleate haem systems. In heated systems the haemoprotein again appeared to be a more effective catalyst than inorganic iron at levels appropriate to those found in meat. It is concluded that the conflicting results as to the roles of haem pigments and inorganic iron in lipid oxidation found in the literature are due, at least in part, to the difficulty of evenly dispersing the catalysts in the washed fibres, especially if heat or freezing leads to subsequent phase separation, and that H(2)O(2), formed by autoxidation of the oxypigments, may be necessary for ferric haem pigments to be effective catalysts.     

Questionnaire development: an examination of the Nordic Musculoskeletal questionnaire

This paper describes the outcome of user trials of the Nordic Musculoskeletal Questionnaire which encompassed the views of the following groups: data entry clerks, technical staff, administrative clerks and 481 subjects employed in 10 supermarkets. A significant number of improvements was identified, especially concerning its wording, layout and administration. This has led to a standardized version being produced for use in studying the prevalence of reported symptoms in many types of occupational groups.