AbstractMultivariate Time Series (MTS) data obtained from large scale systems carry resourceful information about the internal system status. Multivariate Time Series Clustering is one of the exploratory methods that can enable one to discover the different types of behavior that is manifested in different working periods of a system. This knowledge can then be used for tasks such as anomaly detection or system maintenance. In this study, we make use of the statistical method, Variable Order Markov Models (VOMMs) to model each individual MTS and employ a new metric to calculate the distances between those VOMMs. The pairwise distances are then used to accomplish the MTS Clustering task. Two other MTS Clustering methods are presented and the superiority of the proposed method is confirmed with the experiments on two data sets from Cyber-Physical Systems. The computational complexity of the presented methods is also discussed. 相似文献
We previously reported that energy restriction (ER) of mice attenuated age-associated increases in serum levels of interleukin-6 (IL-6). Here, we studied peripheral blood mononuclear cells (PBMC) from male rhesus monkeys to investigate the following: 1) the production of IL-6 and other cytokines become dysregulated with aging; 2) ER influences cytokine production and mRNA expression; and, 3) oxidative stress, as induced in vitro by xanthine and xanthine oxidase (X/XOD), influences cytokine mRNA and protein levels. Two types of comparisons were made as follows: 1) between normally fed young (6-9 y) and old monkeys (22-33 y); and 2) between middle-aged monkeys (15-21 y) fed either a normal energy intake or subjected to ER (for 5.5 y at 30% less than base-line intake). IL-6 protein levels and X/XOD-induced IL-6 mRNA levels in PBMC from old monkeys were significantly greater than those in PBMC from young animals. In contrast, interleukin-1beta (IL-1beta) and interleukin-8 mRNA levels were not strongly influenced by advancing age. X/XOD, which increased levels of protein carbonyls (indicative of oxidative damage) in PBMC, induced the expression of all three cytokines. ER reduced IL-6 protein and mRNA levels induced by X/XOD and the unstimulated mRNA levels of IL-1beta. These results indicate that, in a nonhuman primate model, oxidative stress may contribute to age-associated increases in the levels of certain cytokines and that adult-onset ER partially ameliorates this alteration. 相似文献
Frequencies of HPV type 16 and 18, evaluated by in situ hybridization technique in uterine cervix carcinomas of the IIIrd stage of clinical advancement, were 54% and 36.5% respectively. Presence of p 21 protein was detected in 85.3% cases of the cancers and showed no relation to HPV infection. 相似文献
First impressions of people's personalities are often formed by using the visual appearance of their faces. Defining how quickly these impressions can be formed has critical implications for understanding social interactions and for determining the visual properties used to shape them. To study impression formation independent of emotional cues, threat judgments were made on faces with a neutral expression. Consequently, participants' judgments pertained to the personality rather than to a certain temporary emotional state (e.g., anger). The results demonstrate that consistent first impressions can be formed very quickly, based on whatever information is available within the first 39 ms. First impressions were less consistent under these conditions when the judgments were about intelligence, suggesting that survival-related traits are judged more quickly. The authors propose that low spatial frequencies mediate this swift formation of threat judgments and provide evidence that supports this hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
Tested the predictive utility of the health belief model for adherence with a complex, ongoing medical regimen in 56 adolescent outpatients (aged 10–19 yrs) with insulin-dependent diabetes mellitus. A 3-construct model of health beliefs was tested: Threat (perceived susceptibility combined with severity), Benefits–Costs, and Cues to seek treatment. The Benefits–Costs and Cues constructs were related to compliance in the positive direction. Threat interacted with Benefits–Costs in the prediction of compliance and with Cues in the prediction of metabolic control. The greatest compliance was achieved with low perceived Threat and high perceived Benefits–Costs. Poor metabolic control was associated with high Threat and Cues. As age increased, adherence to the exercise, injection, and frequency components of the regimen decreased. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
OBJECTIVES: To determine the value of hidrocolonic ultrasound in the detection of proliferative lesions in the colon and to compare it with other techniques of already proven value. MATERIAL AND METHODS: We performed a prospective blinded trial including 155 patients (82 males and 73 females) with ages ranging from 33 to 94 years (average of 58) and clinical and analytical criteria suggesting the existence of colonic proliferative lesions. Patients with rectal mass or those with deficient bowel preparation were excluded. Ultrasound findings were compared to those obtained by colonoscopy (133 cases) and by Barium RX studies (22 cases) and all diagnoses were always confirmed by histologic exams. RESULTS: 155 patients were studied. 50 of them had cancer and 46 of these 50 were diagnosed by Hidrocolonic Ultrasound (92%); 19 had polyps > 7 mm. and 15 of these (78.9%) were diagnosed by Hidrocolonic Ultrasound. Hidrocolonic Ultrasound failed to detect all the polyps < 7 mm. The overall sensitivity, specificity, positive predictive value and negative predictive value for identifying colon carcinoma were 92%, 98%, 95.8% and 96.2% respectively and for polyps > 7 mm were 78.9%, 100%, 100% and 97.1%, respectively. The mean time for examination was 14 minutes. Tolerance was good in 114 patients (73.5%), 29 showed a slight discomfort (18.7%) and 12 (7.7%) showed a great discomfort. There were no complications. CONCLUSIONS: Hidrocolonic ultrasound is an innocuous, fast, well tolerated technique for detecting colonic proliferative lesions > 7 mm H.U. can be considered as a useful complementary technique to other more expensive and invasive ones, such as barium RX studies and Colonoscopy. 相似文献
Investigators and clinicians are sometimes confronted with the task of determining whether a pattern of scores on a variety of measures reflects impairment. As the number of measures increases, so does the probability that scores on some of the measures will be in the abnormal range. A simple method for setting an overall criterion for abnormality when using multiple measures is presented, and an approach for setting criteria when some of the measures are correlated is suggested. The approach is applied to a study of the neuropsychological manifestations of HIV-I infection, and the model is found to agree with observed results. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
This paper presents the system architecture of a collaborative virtual environment in which distributed multidisciplinary teams involved in space exploration activities come together and explore areas of scientific interest of a planet for future missions. The aim is to reduce the current challenges of distributed scientific and engineering meetings that prevent the exploitation of their collaborative potential, as, at present, expertise, tools and datasets are fragmented. This paper investigates the functional characteristics of a software framework that addresses these challenges following the design science research methodology in the context of the space industry and research. An implementation of the proposed architecture and a validation process with end users, based on the execution of different use cases, are described. These use cases cover relevant aspects of real science analysis and operation, including planetary data visualization, as the system aims at being used in future European missions. This validation suggests that the system has the potential to enhance the way space scientists will conduct space science research in the future.