In designing sociotechnical systems, accounting for the phenomenon of self-organisation is critical. Empirical studies show that workers in these systems adapt not just their individual behaviours, but also their collective structures to deal with complex work environments. The concept of self-organisation can explain how such adaptations can be achieved spontaneously, continuously, and relatively seamlessly, and why this phenomenon is important for dealing with instability, uncertainty, and unpredictability in the task demands. However, existing design approaches such as resilience engineering and cognitive work analysis are limited in their capacity to design for self-organisation. This paper demonstrates that the diagram of work organisation possibilities, a recent addition to cognitive work analysis, provides a sound theoretical basis for designing for self-organisation. That is, it shows how essential components of the diagram are aligned with the concept of self-organisation and are well-grounded in empirical observations of adaptation in a variety of sociotechnical systems, specifically emergency management, military, and healthcare systems. Consequently, designs based on this diagram should have the potential to facilitate the emergence of new spatial, temporal, and functional organisational structures from the flexible actions of individual, interacting actors, thereby enhancing a system’s capacity for dealing with a dynamic, ambiguous work environment. Future research should focus on validating these ideas and demonstrating their value in industrial settings.
Harmonic elimination problem in PWM inverter is treated as an optimization problem and solved using particle swarm optimization (PSO) technique. The derived equation for computation of total harmonic distortion (THD) of the output voltage of PWM inverter is used as the objective function in the PSO algorithm. The objective function is minimized to contribute the minimum THD in the voltage waveform and the corresponding switching angles are computed. The method is applied to investigate the switching patterns of both unipolar and bipolar case. While minimizing the objective function, the individual selected harmonics like 5th, 7th, 11th and 13th can be controlled within the allowable limits by incorporating the constraints in the PSO algorithm. The results of the unipolar case using five switching angles are compared with that of a recently reported work and it is observed that the proposed method is effective in reducing the voltage THD in a wide range of modulation index. The simulated results are also validated through suitable experiments. 相似文献
Exploring a virtual model under simulated environments is the best way to learn about a real system. This is particularly true in robotics where it is quite expensive to provide the system to each individual. The interdisciplinary area of robotics is being studied commonly in various fields like electrical, computer, mechanical engineering, nanotechnology, etc. A virtual robot system can help one fully understand the controls and working of a robot. The system may also be helpful to design the path and plan the trajectory of a robot in an industrial environment or other robotics application. Virtual model of RV-M1 robot has been developed in the MATLAB environment. The virtual system performs forward kinematics and inverse kinematics in addition to providing a simulation of the robot teachbox. 相似文献
There is a need to develop large-aperture acousto-optic tunable filters (AOTFs) in the UV region for applications in astronomy, environmental sciences, biology, etc. We have developed a high-quality noncollinear AOTF cell that uses a single crystal of KDP that has nearly a four times larger acousto-optic figure of merit, M2, than quartz. The linear and angular apertures of this cell are 1.5 cm x 1.5 cm and 1.2 degrees, respectively. The spectral range is 220-480 nm, with 160-cm(-1) spectral resolution and high transmission in the UV. We present an analysis of the design and describe the characterization results. 相似文献
Profiles of flavonoid compounds of Apis mellifera and Melipona spp. honeys from Venezuela were analysed to evaluate entomological-dependent differences. The presence of ellagic acid was
a characteristic of A. mellifera honeys from Venezuela, but its presence was variable in Melipona spp. samples. The number of flavonoid types present in individual samples did not exceed six and occasionally only one phenolic
type was present. The diversity of flavonoid compounds in tropical honeys from Venezuela was lower than that previously measured
in temperate honeys. Flavonoids such as myricetin, an unidentified chalcone and a flavonol glycoside were only found in Melipona honeys but not in all the samples; therefore, they cannot be foreseen as entomological markers to differentiate between the
Apis and Melipona honeys under study. A preliminary discussion is made regarding flavonoids present in Melipona honeys and their probable link with the putative anticataract action of stingless bee-honeys.
Received: 22 February 1996 相似文献
Non‐digestible carbohydrate fraction (NDCF) consists of a range of bioactive compounds that escape digestion in the small intestine. NDCF is mainly composed of dietary fibre (DF) and non‐digestible oligosaccharides (NDO). The objective of this work was to analyse directly and compare the NDCF in two Brazilian cultivars of soybean seed with commercial flour. Brazil is the second major soybean producer in the world. The seed cultivars showed on average a NDCF value of 32.80 g per 100 g dry weight (dw). Regarding DF, insoluble DF (IDF) was the main fraction amounting on average to 98%. Uronic acids were significantly higher than neutral sugar (NS) in IDF and soluble DF (SDF) fractions. There was a considerable amount of Klason lignin – on average 84.14% of DF. Regarding NS profile, mannose was the most important sugar in SDF, whereas galactose and arabinose were predominant in IDF. Stachyose was the main oligosaccharide in NDO. DF and NDO were in the same proportion (94.2:5.8) in tested cultivars. No differences in swelling, water retention, or oil retention capacities between seed cultivars were detected. This study on non‐digestible carbohydrate components in soybean seed gives a different approach to the current nutritional knowledge on protein and oil constituents. 相似文献