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21.
La The Vinh Sungyoung Lee Hung Xuan Le Hung Quoc Ngo Hyoung Il Kim Manhyung Han Young-Koo Lee 《Applied Intelligence》2011,35(2):226-241
Activity recognition is becoming an important research area, and finding its way to many application domains ranging from
daily life services to industrial zones. Sensing hardware and learning algorithms are two important components in activity
recognition. For sensing devices, we prefer to use accelerometers due to low cost and low power requirement. For learning
algorithms, we propose a novel implementation of the semi-Markov Conditional Random Fields (semi-CRF) introduced by Sarawagi
and Cohen. Our implementation not only outperforms the original method in terms of computation complexity (at least 10 times
faster in our experiments) but also is able to capture the interdependency among labels, which was not possible in the previously
proposed model. Our results indicate that the proposed approach works well even for complicated activities like eating and
driving a car. The average precision and recall are 88.47% and 86.68%, respectively, which are higher than results obtained
by using other methods such as Hidden Markov Model (HMM) or Topic Model (TM). 相似文献
22.
PT Lakkakorpi I Nakamura RM Nagy JT Parsons GA Rodan LT Duong 《Canadian Metallurgical Quarterly》1999,274(8):4900-4907
Bone resorption is initiated by osteoclast attachment to the mineralized matrix, cytoskeletal reorganization, cellular polarization, and the formation of the sealing zone. The present study examines the interaction between PYK2 and p130(Cas) (Crk-associated substrate), suggested to be part of the signaling pathway initiated by osteoclast adhesion. Using murine osteoclast-like cells (OCLs) and their mononuclear precursors (pOCs), generated in a co-culture of bone marrow and osteoblastic MB1.8 cells, we show that: 1) p130(Cas) is tyrosine-phosphorylated upon adhesion of pOCs to vitronectin or ligation of beta3 integrins; 2) p130(Cas) colocalizes with PYK2 and the cytoskeletal proteins F-actin, vinculin, and paxillin in the podosomal-rich ring-like structures of OCLs plated on glass and in the sealing zone in actively resorbing OCLs on bone; 3) p130(Cas) and PYK2 form a stable complex in pOCs, independent of tyrosine phosphorylation of either molecule, and this complex is present in Src (-/-) OCLs, in which neither protein is phosphorylated or associated with the osteoclast adhesion structure; 4) the association of p130(Cas) and PYK2 is mediated by the SH3 domain of p130(Cas) and the C-terminal domain of PYK2. These findings suggest that p130(Cas) and its association with PYK2 may play an important role in the adhesion-dependent signaling that leads to cytoskeletal reorganization and formation of the sealing zone during osteoclast activation. 相似文献
23.
JB Tyrrell KR Lamborn LT Hannegan CB Applebury CB Wilson 《Canadian Metallurgical Quarterly》1999,44(2):254-61; discussion 261-3
OBJECTIVE: Prolactinomas are frequently treated primarily with dopamine agonists; however, these agents have disadvantages and require life-long therapy. We therefore reassessed transsphenoidal microsurgery as an alternative therapy. METHODS: We reviewed the data for 121 female patients treated surgically for prolactinomas between 1976 and 1979 (Group 1) and 98 patients treated between 1988 and 1992 (Group 2). RESULTS: Of 219 women, 92% with preoperative prolactin (PRL) values of < or = 100 ng/ml and 91% with intrasellar microadenomas experienced initial remission; 80 to 88% of patients with intrasellar macroadenomas or macroadenomas showing moderate suprasellar extension or focal sphenoid sinus invasion experienced remission. Women with PRL values of > 200 ng/ml and those with larger and more invasive adenomas experienced poorer outcomes (37-41% remission). Lower preoperative PRL values and adenoma stage were the best predictors of initial surgical outcomes. At the most recent evaluations, 89% of women who experienced initial remission continued to experience clinical remission; 85% exhibited normal PRL values, and 5% demonstrated mild, asymptomatic, recurrent hyperprolactinemia (PRL values of < 34 ng/ml). In Group 1, 84% of patients continued to experience remission (82% with normal PRL values) after a median follow-up period of 15.6 years. In Group 2, 97% of patients continued to experience remission (88% with normal PRL values) after a median follow-up period of 3.2 years. Lower postoperative PRL values were the best predictors of long-term remission. CONCLUSION: Transsphenoidal microsurgery is an effective alternative to long-term medical therapy for selected patients with prolactinomas. Successful outcomes and long-term remission were achieved in patients with microadenomas and noninvasive macroadenomas. 相似文献
24.
Guillaume Sébastien; Sang Caroline Ngo Ton; Jaussent Isabelle; Raingeard Isabelle; Bringer Jacques; Jollant Fabrice; Courtet Philippe 《Canadian Metallurgical Quarterly》2010,24(6):808
Objective: Decision making has been reported to be reduced in eating disorders. However, studies are sparse and have been carried out in various selected populations. In the current study we arranged to confirm previous observations and to assess the relationship between decision making and dimensions relevant to eating disorders. Method: Patients suffering from anorexia nervosa (n = 49), bulimia nervosa (n = 38), and healthy controls (n = 83) were assessed using the Iowa Gambling Task (IGT). All patients were euthymic and free of psychotropic medication. Self-questionnaires (Eating Disorder Inventory–2; Gardner, 1991; and Eating Attitude Test; Garner & Garfinkel, 1979) were used to assess clinical dimensions relevant to eating disorders. Results: No significant differences in IGT performance were observed between patients and healthy controls or between restrictive and purging types of anorexia nervosa. No correlations were found between IGT performance and eating disorder questionnaires. Conclusion: These results do not support reduced decision making in patients with eating disorders, and suggest that previously reported alterations could be related to other clinical characteristics. This should stimulate new topic-related studies designed to reach a firm conclusion. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
25.
Design of pedestrian friendly vehicle bumper 总被引:2,自引:0,他引:2
Tso-Liang Teng Van-Luc Ngo Trong-Hai Nguyen 《Journal of Mechanical Science and Technology》2010,24(10):2067-2073
Car-pedestrian accidents take thousands of lives worldwide annually. Therefore, pedestrian protection is an important issue
in traffic safety. How to consider a pedestrian friendliness vehicle and then propose pedestrian protection methods are urgent
works for minimizing pedestrian injury. For designing a pedestrian friendly vehicle bumper, this study adopts the European
Enhanced Vehicle-safety Committee/ Working Group 17 (EEVC/WG17) regulations of legform impactor to bumper tests. Analyzing
the pedestrian friendliness of a vehicle bumper by using LS-DYNA is described in detail. Simulation results were analyzed
to identify the reasons for the unfriendliness. Furthermore, the analysis of the influence of bumper structure on pedestrian
leg was performed and then some guideline was suggested. The analyzed models and results obtained could help evaluate pedestrian
friendliness of a vehicle and guide the future development of pedestrian friendly vehicle technologies. 相似文献
26.
Robert O. Dunn Victor T. Wyatt Karen Wagner Helen Ngo Megan E. Hums 《Journal of the American Oil Chemists' Society》2019,96(7):805-823
Biodiesel (fatty acid methyl esters [FAME]) is produced from various fats, oils, and greases (FOG) using catalytic transesterification with methanol. These fuels have poor cold-flow properties depending on the fatty acid (FA) composition of the parent FOG. Improving the cold-flow properties of biodiesel will enhance its prospects for use during cooler months in moderate temperature climates. This work is a study on the use of skeletally branched-chain alkyl esters (BCAE) composed of the isopropyl, n-butyl, and 2-ethylhexyl esters of iso-oleic acid isomers (iPr-iOL, nBu-iOL, and 2EH-iOL). These BCAE additives were tested in blends with linear-FAME (L-FAME) derived from soybean oil (SME), lard (LME), tallow (TME), and sewage scum grease (SGME). Binary L-FAME/SME admixtures were also studied. Admixtures were tested for the effects of the additives on cloud point (CP), pour point (PP), and kinematic viscosities at standard (ν40 = 40 °C) and low temperatures (TL) = CP + 5 °C (νL). Although the BCAE additives were more effective than SME, relatively large additive concentrations (yAdd) were needed to depress CP and PP by more than 2 °C. Admixtures with high concentrations of BCAE additive had ν40 > 6.0 mm2 s−1, the maximum limit in ASTM fuel specification D 6751. While the iPr-iOL and nBu-iOL additives may be blended at concentrations up to yAdd = 0.50, 2EH-iOL should not exceed yAdd = 0.28 in LME, 0.31 in SGME, 0.35 in TME, or 0.41 in SME to avoid driving the admixture out of specification. Some anomalies observed in the results at low yAdd for SGME/BCAE admixtures were speculated to have been affected by the low-temperature rheology of SGME. 相似文献
27.
Using 3D-CFD code, Nusselt number correlations for a microchannel heat exchanger (MCHE) with S-shaped fins used for hot water suppliers are obtained through numerical experiments and then validated. The supercritical carbon dioxide working fluid is assumed to operate around the pseudo-critical point, where fluid properties change radically. Calculations with 20 different temperatures are executed to produce Nusselt number correlations for each side. The fluid inlet temperature in each calculation is defined as 2 °C lower or higher than the constant wall temperature, respectively, for cold and hot side simulations. The small temperature difference of 2 °C is sufficiently small to regard thermal–hydraulic properties as constant. A new integrating method using the correlations to calculate the heat-transfer-performance is proposed. The resultant heat-transfer-performance is compared with that of another numerical result, which is reduced from large geometry and integration. The results agree within 3% error; the calculation accuracy of the method is confirmed. Experimental results with MCHE verify the correlations. The difference is approximately 5%. Using few computer resources, these Nusselt number correlations and the heat-transfer-performance calculation methods using correlation information are sufficiently accurate to evaluate heat exchangers. 相似文献
28.
Stabilization of red anthocyanins on the surface of thermally processed red pears (D'Anjou) through complexation with metallic ions and polymerization was investigated. Pears were treated briefly in an aqueous solution containing stannous (Sn) ion, hydrochloric acid, formaldehyde, and tannic acid prior to steaming and canning processes. Polymerization capacity of the treatment solutions was investigated by monitoring the haze formation of the solutions. Aqueous acetone extracts of the peels from fresh and treated pears at major processing steps (pre-treatment, steam-heating, and canning) were subjected to HPLC qualitative analysis on anthocyanins. The total phenolics (TP) and anthocyanin content (ACN) of the peels were measured by Folin-Ciocalteu assay and pH-differential method, respectively. Polymerization capacity of the solution was influenced by the composition, setting-time, and the time of Sn addition into the formulated solutions. The pre-treatment along with steam-heating resulted in stable red pigments on the peels of canned pears. The new pigments are believed to be the complexes of stannous and phenolics, including anthocyanins. No major newly formed anthocyanins or small phenolics were detected in treated pears. Although developed treatment formula did not represent a commercial application yet, this study revealed an effective approach of retaining red anthocyanins on thermally processed fruits. 相似文献
29.
On the SEP of Cooperative Diversity with Opportunistic Relaying 总被引:1,自引:0,他引:1
We analyze the exact symbol error probability (SEP) of cooperative diversity with opportunistic amplify-and-forward (AF) relaying. The benefit of this opportunism to the SEP is assessed by comparing with maximal ratio combining of orthogonal multiple AF relay transmissions. 相似文献
30.