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Objective: In community-based epidemiological studies, job-and industry-specific 'modules' are often used to systematically obtain details about the subject's work tasks. The module assignment is often made by the interviewer, who may have insufficient occupational hygiene knowledge to assign the correct module. We evaluated, in the context of a case-control study of lymphoid neoplasms in Asia ('AsiaLymph'), the performance of an algorithm that provided automatic, real-Time module assignment during a computer-Assisted personal interview. Methods: AsiaLymph's occupational component began with a lifetime occupational history questionnaire with free-Text responses and three solvent exposure screening questions. To assign each job to one of 23 study-specific modules, an algorithm automatically searched the free-Text responses to the questions 'job title' and 'product made or services provided by employer' using a list of module-specific keywords, comprising over 5800 keywords in English, Traditional and Simplified Chinese. Hierarchical decision rules were used when the keyword match triggered multiple modules. If no keyword match was identified, a generic solvent module was assigned if the subject responded 'yes' to any of the three solvent screening questions. If these question responses were all 'no', a work location module was assigned, which redirected the subject to the farming, teaching, health professional, solvent, or industry solvent modules or ended the questions for that job, depending on the location response. We conducted a reliability assessment that compared the algorithm-Assigned modules to consensus module assignments made by two industrial hygienists for a subset of 1251 (of 11409) jobs selected using a stratified random selection procedure using module-specific strata. Discordant assignments between the algorithm and consensus assignments (483 jobs) were qualitatively reviewed by the hygienists to evaluate the potential information lost from missed qu

Railway timetabling is an important process in train service provision as it matches the transportation demand with the infrastructure capacity while customer satisfaction is also considered. It is a multi-objective optimisation problem, in which a feasible solution, rather than the optimal one, is usually taken in practice because of the time constraint. The quality of services may suffer as a result. In a railway open market, timetabling usually involves rounds of negotiations amongst a number of self-interested and independent stakeholders and hence additional objectives and constraints are imposed on the timetabling problem. While the requirements of all stakeholders are taken into consideration simultaneously, the computation demand is inevitably immense. Intelligent solution-searching techniques provide a possible solution. This paper attempts to employ a particle swarm optimisation (PSO) approach to devise a railway timetable in an open market. The suitability and performance of PSO are studied on a multi-agent-based railway open-market negotiation simulation platform.

Sydney, with many of its heritage buildings and monuments constructed as a result ofthe first European settlement in the l800s, is a city built on a large block of sandstone. Although many ofthese buildings are still strong and sound, signs of deterioration have become evident in recent years. In order to prevent these precious buildings from further degradation, the weathering mechanisms of the stones must be thoroughly understood before suitable protection measures can be implemented. In this study, four techniques have been selected to detect chemical and physical differences between weathered and unweathered sandstones - Solid State Nuclear Magnetic Resonance (NMR) Spectroscopy, Thermogravimetric analysis (TGA), Differential Scanning Calorimetry (DSC) and X-ray Photoelectron Spectroscopy (XPS).

This paper presents a feasibility study on locating damage in circular cylindrical fiber-reinforced composite shells based on natural frequencies and mode shape information at specific locations. The axial position of the damage is located by comparing the measured and the predicted frequency changes due to introducing damage. The theoretical frequency changes are approximated by frequency sensitivities. The advantage is that a damaged shell model is not required, as frequency sensitivities are readily obtained from a defect-free finite element model. As the shells are axisymmetric, additional information on mode shape is employed to locate the exact damage position. Results from simulations showed that the proposed detection scheme can easily locate damage in free-free and simply-supported shells. For a clamped-free shell, a successful detection scheme is secured by excluding those vibration modes with a highly nonlinear response to the severity of damage. The robustness of the proposed method in the presence of both modelling and measurement errors is demonstrated by simulation.

An investigation of thermodynamic stability of ion-implanted hydrogen in ZnO was presented. Secondary ion mass spectrometry was used for the analysis. Rutherford backscattering/channeling of samples implanted with 1H showed no change in backscattering yield near the ZnO surface. It was found by cathodoluminescence and photoluminescence studies that the intensity of the near gap emission from ZnO is reduced more than two orders of magnitude from the values in unimplanted samples.

This technical note presents the optimal position and orientation of a piezoelectric patch actuator for improving the controllability of isotropic plates against vibration. The main focus is on controlling the first five modes either individually or simultaneously. Four rectangular aluminum plates of different aspect ratios and of either simply-supported or cantilevered boundary condition are considered. A formula incorporating results from finite-element analyses is developed to predict the steady-state responses of plates driven by a single piezoelectric patch. Simulation results show that, in general, the controllability of plates is insensitive to patch orientation as far as the present investigation is concerned. For the simply-supported plates, the optimal patch positions coincide exactly with anti-nodes of the vibration modes being considered. This, however, is only true for specific modes of the cantilevered plates.