Propane conversion over zeolite catalysts: Comments on the role of Ga

The activation of propane using zeolite H-Y and Ga³⁺ exchanged zeolite Y indicates that in the presence of Ga³⁺ the mechanism of propane activation is changed from a cracking pathway to a dehydrogenation pathway. The presence of both Ga³⁺ and H⁺ are required to achieve this effect.     

EXTENSION OF THE RELATIONAL DATABASE AND ITS ALGEBRA WITH ROUGH SET TECHNIQUES

This paper describes a database model based on the original rough sets theory. Its rough relations permit the representation of a rough set of tuples not definable in terms of the elementary classes, except through use of lower and upper approximations. The rough relational database model also incorporates indiscernibility in the representation and in all the operators of the rough relational algebra. This indiscernibility is based strictly on equivalence classes which must be defined for every attribute domain. There are several obvious applications for which the rough relational database model can more accurately model an enterprise than does the standard relational model. These include systems involving ambiguous, imprecise, or uncertain data. Retrieval over mismatched domains caused by the merging of one or more applications can be facilitated by the use of indiscernibility, and naive system users can achieve greater recall with the rough relational database. In addition, applications inherently “rough” could be more easily implemented and maintained in the rough relational database.     

基于数据融合的居民区建筑物重建方法研究

针对美国新奥尔良地区稀疏的LiDAR （Light Detecting and Ranging）点云数据,提出了一种基于LiDAR数据和卫星图像进行融合的居民区建筑物重建方法.该方法利用LiDAR数据点集的边界来定位卫星图像上的感兴趣区域,利用从感兴趣区域中提取的关键提示线来实现屋顶的分割,从而得到属于每个建筑物的屋顶点.然后,基于三角面片的法向量方向信息对其进行聚类,根据法向量之间的关系进行屋顶类型识别,从而实现居民区建筑物的重建.实验表明,该方法在进行居民区建筑物重建时,能达到较高的重建率,且重建所需时间合理,能够满足虚拟现实系统的需要.     

Cognitive and motor functioning in Parkinson disease: subjects with and without questionable dementia

We evaluated the data of the National Collegiate Athletic Association Injury Surveillance System on collegiate wrestling with a focus on musculoskeletal injuries. Over 800,000 athlete-exposures during an 11-year period compose these data. Findings particular to wrestling and a comparison with other collegiate sports are included. Collegiate wrestling had a relatively high rate of injury at 9.6 injuries per 1000 athlete-exposures. It was second to spring football in total injury rate. Most injuries in this study were not serious, with 6.3% resulting in surgery and 37.6% resulting in a week or more off from wrestling. There was only one catastrophic, nonfatal injury. The knee, shoulder, and ankle were the most commonly injured regions, and injuries to them were often the more serious. Sprains, strains, and contusions were the most common injury types. Takedowns and sparring were the most common activities at the time of injury. Mechanism of injury was evaluated; rotation about a planted foot and contact with environmental objects were identified as areas needing further attention. Illegal action accounted for only 4.6% of injuries in competition. Competition had a significantly higher injury rate than practice, but the injury profiles of these two areas showed both to be equally important. The preseason and regular season had higher injury rates than the postseason, but, again, the injury profiles of these periods were similar. Injury percentages were similar among the 10 weight classes.     

Uncertainty management issues in the object-oriented data model

This paper fully develops a previous approach by George et al. (1993) to modeling uncertainty in class hierarchies. The model utilizes fuzzy logic to generalize equality to similarity which permitted impreciseness in data to be represented by uncertainty in classification. In this paper, the data model is formally defined and a nonredundancy preserving primitive operator, the merge, is described. It is proven that nonredundancy is always preserved in the model. An object algebra is proposed, and transformations that preserve query equality are discussed     

Operation Research Methodologies in Industrial Engineering: A Survey

This study presents the results of a survey taken among members of the Operations Research Division of the American Institute of Industrial Engineers as to perceived utility and familiarity with twelve methodologies commonly used in Industrial Engineering practice. A modification to the method of majority rule for weighting the opinions of respondents, based upon their degree of familiarity or expertise, is also presented.     

Wireless capsule endoscopy video segmentation using an unsupervised learning approach based on probabilistic latent semantic analysis with scale invariant features

Since wireless capsule endoscopy (WCE) is a novel technology for recording the videos of the digestive tract of a patient, the problem of segmenting the WCE video of the digestive tract into subvideos corresponding to the entrance, stomach, small intestine, and large intestine regions is not well addressed in the literature. A selected few papers addressing this problem follow supervised leaning approaches that presume availability of a large database of correctly labeled training samples. Considering the difficulties in procuring sizable WCE training data sets needed for achieving high classification accuracy, we introduce in this paper an unsupervised learning approach that employs Scale Invariant Feature Transform (SIFT) for extraction of local image features and the probabilistic latent semantic analysis (pLSA) model used in the linguistic content analysis for data clustering. Results of experimentation indicate that this method compares well in classification accuracy with the state-of-the-art supervised classification approaches to WCE video segmentation.     

Assessment of the maximum frequency components and digital sampling of cardiac Purkinje fiber action potentials

An investigation was made into a reasonable continuous sampling frequency for cardiac Purkinje fiber action potentials. Under the assumption that digital sampling will effectively capture frequency components up to half the sampling rate, action potential records made at 25 kHz were low-pass filtered at various cutoff frequencies. The filtered and unfiltered records were compared by calculating Vmax to determine the effects of progressive loss of high frequency components. It was determined that sampling at 13 kHz is adequate for action potentials with upstroke velocities up to 500 V/sec, and that estimation of Vmax in excess of 800 V/sec is possible.     

Evidence for the reversible formation of a catalytic active site for propane aromatization for Ga2O3/H-ZSM-5

The specific activities of catalysts formed by thermal activation of the layered double hydroxide [Mg_2.34Al (OH)_6.68] (CO₃)_0.5·2.6H₂O have been determined using 2-methyl-3-butyn-2-ol (MBOH) as an acid/base-selective substrate. Acetone and acetylene were the only reaction products formed over the temperature range 80–150°C, demonstrating that all of the LDHderived catalysts have highly basic selectivities. Thermal activation below the structural decomposition point of the LDH (250°C) afforded catalysts with specific activities approximately an order of magnitude larger than the amorphous metal oxides and crystalline MgAl₂U₄ spinel-MgO mixtures formed by thermal activation at 450 and 890°C, respectively. Even the remnant LDH structure formed by partial decarbonation/dehydroxylation at 350°C was substantially more active than the more commonly used metal oxide derivatives.     

多颜色空间中目标约束的车辆阴影分割研究

智能交通系统希望从交通视频中获取车辆的相关信息来管理交通流,而视频中车辆阴影的检测和移除是移动车辆检测的一个关键问题。首先提出一种新颖的背景模型更新方法,它是基于从前帧学习到的目标知识来更新背景模型;其次提出一种新的颜色空间,VIRGBC颜色空间,进行车辆阴影分割,它是通过从不同颜色空间中提取对阴影敏感的光谱特征和几何特征进行融合获得VIRGBC颜色特征;然后分别对VIRGBC颜色空间中各通道利用条件随机场进行训练,利用调和平均数合并获得分割结果。实验结果表明,该方法的precision\|recall曲线下的面积为93.5%,比现有其他算法获得更好的结果。