Papers by Keyword: CAMX

Abstract: In this study, a coupled MM5-CAMx air quality modeling system was proposed for simulating the SO₂ concentration in Beijing, China during the heating season. The Particulate Source Apportionment Technology (PSAT) was introduced into the modeling system to investigate SO₂ source apportionment from regions nearby Beijing and regions in Beijing. The results indicated that the influence from regions outside of Beijing including Hebei, Tianjin and Shanxi could not be ignored, and the total Emission Source Contribution Ratio (ESCR) from these regions was 10.8%. Metropolitan Beijing, including Chaoyang, Fengtai, the city center of Beijing, Haidian, and Shijingshan, with an ESCR of 82.5%, was the main contributing area in Beijing. The results obtained could provide useful information for Beijing’s SO₂-emission control and abatement. This method could effectively identify SO₂ pollution problem in a metropolis region and thus provide a scientific basis for air pollution control and mitigation.

Abstract: Three different and complementary ways of adaptive control are presented, each working on a different time scale. All three of them are made possible due to evolutions and developments in CNC controls. The first and most popular way of adaptive control is adaptive process control. Since the process variables in sheet metal equipment change significantly in milliseconds, the control loop must also perform on a sub second time scale. The second adaptive loop is adaptive production control. Modern CNC controls know what they are manufacturing and talk with higher production software. Instead of just executing a planning that came top down, the CNC has enough knowledge of its environment that it can propose an intelligent job sequence and hence react more effectively on unforeseen situations. These adaptive loops perform on a time scale of hours and days. The third adaptive loop is adaptive resource control. To produce sheet metal parts, we need several kinds of resources: human resources, material, consumables, energy and equipment. CNC sheet metal equipment is a considerable investment. However most production managers do not know how effective their resources are being used. By applying the principles of overall equipment effectiveness, we can close the resource control loop. This loop performs on a time scale of weeks and months.