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931.
Wind direction data were used to calculate the percentage time during which winds blew over the principal sources of air pollution at Port Kembla into each of the surrounding residential suburbs for each month of 1980. The percentage wind frequencies (PWFs) correlated well with measured concentrations of airborne metals in the suburbs and with measured rates of metal deposition in moss bags located in suburbs adjoining the air pollution sources. PWFs for all suburbs exhibited winter minima and spring-summer maxima, with the highest PWFs being calculated for suburbs south to south-west of the industrial area and the lowest for suburbs lying to the west. Where experimental data are not available, PWFs could provide an indication of air quality for land-use planning and zoning. 相似文献
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The Llyn Padarn wreck is a bateau style vessel of the late 18th century. Assuming that it is one of the boats built by the quarry company it was constructed between February 1788 and February 1789. If it was built by one of the independent boatmen its date of construction is uncertain, however its excellent state of preservation suggests that it was still relatively new when it sank, and this also would point towards it being one of the company boats. Whatever the date of building, the boat certainly sank between 1788 and 1824, but the quality of the cargo suggests that it was towards the beginning rather than the end of that period. It is of historic interest as one of the few surviving examples of the bateau style of boat building. and it is also one of the best preserved examples of its kind. It also throws some light on the early history of the North Wales slate industry, on the history of travel and transport on Llyn Padarn, and on the lake settlements at Cwm y Glo and Penllyn. The Padarn boat is now being put into E'EG conservation by the National Museum of Wales, and will subsequently be exhibited in the North Wales Quarry Museum at Llanberis. It would be interesting to know what happened to all the other boats which were evidently working on the lakes in the 18th and early 19th centuries. No doubt most were destroyed when their usefulness came to an end, but if one sank there may well be others, and in due course the Welsh Institute of Maritime Archaeology hopes to carry out a remote sensing survey of Padarn using side-scan sonar and low light television. In addition, the upper lake, Llyn Peris, is to be drained in connection with the massive Pump Storate Generating Scheme which has once again turned the derelict quarries into one of the largest civil engineering projects in Europe. It is certain that these two lakes still have secrets to reveal. I would like to thank the staff of the North Wales Quarry Museum for their patient assistance and advice in the preparation of this article; Mr Brian Buckle of North Wales Divers Ltd, Colwyn Bay, for providing me with a copy of his survey of the wreck site; Mr Derwyn Jones, the Welsh Librarian in the University Library, Bangor for bringing to my attention various references to Margaret ferch Evans, and my colleague Mr Emlyn Sherrington for translating certain passages from the Welsh. 相似文献
935.
Lincoln P. Bloomfield 《政策研究杂志》1979,8(1):114-119
The U.S. has since World War II followed a defense policy and strategy that combined traditional national approaches with features especially typical of American attitudes toward war and peace as well as force and power. The deep dilemmas of nuclear deterrence confront the U.S. with an inescapable dilemma, which in turn motivates an increasingly serious arms control policy. 相似文献
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