Tycho brahe in china: the Jesuit mission to Peking and the iconography of European instrument-making processes

In the late 1660s, Ferdinand Verbiest, a Flemish Jesuit missionary in Peking, was instructed to re-equip the Imperial Observatory. The new instruments which he caused to be built were modelled neither upon contemporary European prototypes, nor those of traditional Chinese astronomy, but on the pieces in Tycho Brahe's Mechanica, of eighty years before. The Chinese instruments were lavishly illustrated, moreover, in 105 woodcuts that contained detailed representations of their processes of construction. It is argued that these illustrations not only give us valuable insights into what the technical Jesuits did in Peking, but show how sixteenth- and seventeenth-century European craftsmen constructed their instruments, for while the location was Oriental, the technology was Western. They can also give important insights into how Tycho's prototypes had been built, and provide us with useful information regarding European instrument-making technology.     

Chemical reduction of three-dimensional silica micro-assemblies into microporous silicon replicas

The carbothermal reduction of silica into silicon requires the use of temperatures well above the silicon melting point (> or =2,000 degrees C). Solid silicon has recently been generated directly from silica at much lower temperatures (< or =850 degrees C) via electrochemical reduction in molten salts. However, the silicon products of such electrochemical reduction did not retain the microscale morphology of the starting silica reactants. Here we demonstrate a low-temperature (650 degrees C) magnesiothermic reduction process for converting three-dimensional nanostructured silica micro-assemblies into microporous nanocrystalline silicon replicas. The intricate nanostructured silica microshells (frustules) of diatoms (unicellular algae) were converted into co-continuous, nanocrystalline mixtures of silicon and magnesia by reaction with magnesium gas. Selective magnesia dissolution then yielded an interconnected network of silicon nanocrystals that retained the starting three-dimensional frustule morphology. The silicon replicas possessed a high specific surface area (>500 m(2) g(-1)), and contained a significant population of micropores (< or =20 A). The silicon replicas were photoluminescent, and exhibited rapid changes in impedance upon exposure to gaseous nitric oxide (suggesting a possible application in microscale gas sensing). This process enables the syntheses of microporous nanocrystalline silicon micro-assemblies with multifarious three-dimensional shapes inherited from biological or synthetic silica templates for sensor, electronic, optical or biomedical applications.     

A Strategic Study of Establishing the Industrial Needs in Pattern Design and Technology in Mainland China

Pattern design and, technology play a very important role in the garment industry. In order to improve the level of pattern making and design of the garment industry, a survey was conducted to investigate the industrial needs in pattern design and technology in mainland China. The data were collected from the employers and employees from the garment industry and students in the major of fashion and clothing studies. It indicated that there was a gap between the employer and employee, especially the requirements of the industrial needs and the course contents covered by the tertiary schools. The employers expected to recruit more experienced pattern designers, at the same time, they were not reluctant to hire fresh graduates and spent more resources on the training of employees. The students knew little about their employment situation of the garment industry, spent too little time on the course study and learned too little practical skills in pattern design. They could not make use of the knowledge which prevented them from being employed by the garment industry. Efforts should be taken by both the tertiary schools and the garment industry. The students should be aspirated towards the profession of pattern cutters and the syllabuses of pattern making should be more practical and industrial orientated. The solution might benefit the garment industry a lot in a long run.     

A comparative evaluation of objective and subjective weather forecasts in the united states

This paper is concerned primarily with the evaluation and comparison of objective and subjective weather forecasts. Operational forecasts of three weather elements are considered: (1) probability forecasts of precipitation occurrence, (2) categorical (i.e. non-probabilistic) forecasts of maximum and minimum temperatures and (3) categorical forecasts of cloud amount. The objective forecasts are prepared by numerical-statistical procedures, whereas the subjective forecasts are based on the judgements of individual forecasters. In formulating the latter, the forecasters consult information from a variety of sources, including the objective forecasts themselves. The precipitation probability forecasts are found to be both reliable and skilful, and evaluation of the temperature/cloud amount forecasts reveals that they are quite accurate/skilful. Comparison of the objective and subjective forecasts of precipitation occurrence indicates that the latter are generally more skilful than the former for shorter lead times (e.g. 12–24 hours), whereas the two types of forecasts are of approximately equal skill for longer lead times (e.g. 36–48 hours). Similar results are obtained for the maximum and minimum temperature forecasts. Objective cloud amount forecasts are more skilful than subjective cloud amount forecasts for all lead times. Examination of trends in performance over the last decade reveals that both types of forecasts for all three elements increased in skill (or accuracy) over the period, with improvements in objective forecasts equalling or exceeding improvements in subjective forecasts. The role and impact of the objective forecasts in the subjective weather forecasting process are discussed in some detail. The need to conduct controlled experiments and other studies of this process, with particular reference to the assimilation of information from different sources, is emphasized. Important characteristics of the forecasting system in meteorology are identified, and they are used to describe similarities and differences between weather forecasting and forecasting in other fields. Acquisition of some of these characteristics may be beneficial to other forecasting systems.     

Quality/value relationships for imperfect weather forecasts in a prototype multistage decision-making model

Some theoretical results concerning the nature of the relationship between the scientific quality and economic value of imperfect weather forecasts are obtained. A prototype multistage decision-making model is considered, involving only two possible actions and two possible states of weather. This particular form of model is motivated by a real-world application known as the fruit-frost problem. For an infinite-horizon, discounted version of this model it is shown that economic value remains zero below a forecast quality threshold and then rises monotonically but nonlinearly above this threshold. In particular, the relative sensitivity of economic value to changes in the quality of forecasts increases as perfect information is approached. This curve is compared with quality/value relationships that have been obtained for other versions of the model; namely, a single-stage model and a multistage, finite-horizon model.