A PROTOTYPE GRID FRAMEWORK FOR THE CHEMICAL PROCESS INDUSTRIES

This article presents a GRID framework for distributed computations in the chemical process industries. We advocate a generic agent-based GRID environment in which chemical processes can be represented, simulated, and optimized as a set of autonomous, collaborative software agents. The framework features numerous advantages in terms of scalability, software reuse, security, and distributed resource discovery and utilization. It is a novel example of how advanced distributed techniques and paradigms can be elegantly applied in the area of chemical engineering to support distributed computations and discovery functions in chemical process engineering. A prototype implementation of the proposed framework for chemical process design is presented to illustrate the concepts.     

Coherent lightwave transmission at 2 Gbit/s over 170 km of optical fibre using phase modulation

We report coherent lightwave transmission at a data rate of 2Gbit/s over 170 km of optical fibre. Phase modulation is employed, and a bit error rate lower than 10-9 is achieved. The receiver sensitivity of ?39.0 dBm 10-9 BER) is an improvement of 2.4 dB over the best previously published direct-detection result for non-return-to-zero transmission.     

项目计划内在稳健性与其影响因素关系分析

针对资源约束项目计划的内在稳健性受多种因素影响的问题,本研究采用16种优先规则,对Kolisch的j30算例集中的480个算例分别制定项目计划,计算出各项目计划的最少关键序列总数、资源使用效率及项目计划工期比项目最短工期长出的百分比L,并通过仿真得到各项目计划的内在稳健性值;同时应用多元统计方法,建立项目计划内在稳健性与各影响因素之间的回归方程。统计检验结果表明,回归方程是显著有效的,最少关键序列数、资源使用效率与内在稳健性呈负相关,项目计划的工期比项目的最短工期长出的百分比L与内在稳健性呈正相关;交叉项检验结果表明,关键序列较多时,L的增大可以有效地提高项目计划的稳健性,这与实际状况一致。该研究可为具有稳健性项目计划的制定、预测和控制提供决策依据。     

基于黎曼流形的多视角谱聚类算法

现有的多视角谱聚类算法大多只线性结合了各视角的基拉普拉斯矩阵,未考虑不同视角数据的差异性对最优拉普拉斯矩阵的影响,存在聚类性能受限的问题。提出一种基于黎曼几何均值与高阶拉普拉斯矩阵的谱聚类算法(RMMSC),挖掘多视角数据中的高阶连接信息与流形信息,提高最优拉普拉斯矩阵对各视角的信息利用率。按一定的权重线性结合数据单一视角的各阶拉普拉斯矩阵,得到每个视角的基拉普拉斯矩阵,通过低阶与高阶连接信息的结合使用,充分体现多视角数据集的全局结构。在此基础上,计算各视角基拉普拉斯矩阵的黎曼几何均值,将其作为最优拉普拉斯矩阵输入谱聚类算法,得到聚类结果。相比于传统矩阵算数均值的计算,基于黎曼流形的黎曼几何均值能够更好地恢复互补层数据的流形信息。实验结果表明,RMMSC在多组标准数据集上聚类效果优于ONMSC、MLAN、AMGL等算法。其中,在Flower17数据集上,精确度较基准算法ONMSC提高了2.14%,纯度提高了1.7%,且收敛性较好。     

A new data fusion model for high spatial- and temporal-resolution mapping of forest disturbance based on Landsat and MODIS

Investigating the temporal and spatial pattern of landscape disturbances is an important requirement for modeling ecosystem characteristics, including understanding changes in the terrestrial carbon cycle or mapping the quality and abundance of wildlife habitats. Data from the Landsat series of satellites have been successfully applied to map a range of biophysical vegetation parameters at a 30 m spatial resolution; the Landsat 16 day revisit cycle, however, which is often extended due to cloud cover, can be a major obstacle for monitoring short term disturbances and changes in vegetation characteristics through time.The development of data fusion techniques has helped to improve the temporal resolution of fine spatial resolution data by blending observations from sensors with differing spatial and temporal characteristics. This study introduces a new data fusion model for producing synthetic imagery and the detection of changes termed Spatial Temporal Adaptive Algorithm for mapping Reflectance Change (STAARCH). The algorithm is designed to detect changes in reflectance, denoting disturbance, using Tasseled Cap transformations of both Landsat TM/ETM and MODIS reflectance data. The algorithm has been tested over a 185 × 185 km study area in west-central Alberta, Canada. Results show that STAARCH was able to identify spatial and temporal changes in the landscape with a high level of detail. The spatial accuracy of the disturbed area was 93% when compared to the validation data set, while temporal changes in the landscape were correctly estimated for 87% to 89% of instances for the total disturbed area. The change sequence derived from STAARCH was also used to produce synthetic Landsat images for the study period for each available date of MODIS imagery. Comparison to existing Landsat observations showed that the change sequence derived from STAARCH helped to improve the prediction results when compared to previously published data fusion techniques.     

陶瓷烧成中SOx的排放及降低SOx的方法

本文分析了陶瓷烧成过程中S0x的主要来源以及降低SOx排放的方法。同时，还简要介绍了目前主要的几种SOx排放处理方法．并对减少我国陶瓷窑炉燃烧带来的污染提出几点建议。     

Light emission from carbon-based materials under ITER relevant thermal shock loads

Light emission from carbon-based materials (fine grain graphite, CFC and silicon doped CFC) was observed during ITER relevant thermal shock loads by means of in situ optical diagnostics. The light emission which corresponds to particle release clearly indicated different particle release processes in the three materials. The differences were also found in the initiation temperatures of particle release and the surface morphology of the loaded areas. These results are related to the thermal stress in bulk materials. In addition to particle release, vapor cloud formation caused by thermal shock loads were observed as CII lines and lines from the C₂ Swan system. No Si lines but lines from SiC₂ molecules (Merrill-Sanford bands) were observed in Si doped CFC. This indicates that atomic silicon is not released under ITER relevant thermal shock loads.     

Linear and cyclic oligomers in polybutylene terephthalate for food contact materials

Polybutylene terephthalate (PBT) is a polyester (PES) gaining more importance on the food contact material (FCM) market. However, little is known about the potential migration of PBT oligomers which are formed during polymer production. In this work, PBT pellets and a slotted spoon manufactured from this material by injection moulding were analysed on extractable oligomers and their migration potential into hydrophilic foods. Overall 27 oligomers (cycles and linears) could be identified in different extracts by HPLC-DAD/ESI-MS data, but without confirmation by reference substances. The oligomers were quantified by HPLC-DAD using bis(2-hydroxyethyl) terephthalate (BHET) as external standard and the total amount of oligomers isolated by reprecipitation from the pellets and the spoon were 0.69 and 0.71%, respectively. While cyclic oligomers made up for approximately 90% of the extractable oligomers, linear oligomers proved to be more relevant for migration into aqueous foodstuffs. Furthermore, it was shown that hydrolysis of oligomers can take place in water at elevated temperatures. Consequently, the qualitative and quantitative composition of PBT oligomers in aqueous foods from FCMs does not only depend on migration but also on hydrolysis. Migration testing of the PBT spoon under repeat use conditions with water at 100°C for 2 h resulted in 0.29 mg item^?1 of linear oligomers and 0.05 mg item^?1 of the cyclic PBT dimer in the third migrate.     

面向工程领域的主题多样性知识推荐方法

针对现有推荐方法无法同时满足知识推荐准确度和多样性的问题,提出一种主题多样性知识推荐方法(TDKR).基于对企业知识管理现状的分析,提出同时考虑内容、情境、任务3种相似度的知识相关性网络构建方法,进而划分知识主题社区.基于知识主题社区,构建用户兴趣模型,挖掘用户多样性的知识需求,并结合用户群行为数据,提出用户—主题专业...     

纤维基材料的仿生学研究动向

纤维基技术的应用对仿生学的成功发展呈现出巨大的潜力,因为宇宙成物在生长过程、多毛结构和增强纤维方面具有许多相似性.约七年前,邓肯道夫纺织技术与工艺研究所协同众位生物学家一起开创了仿生学的研发,至今方兴未艾.