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131.
132.
Pei-Chann Chang Jyun-Jie Lin Jui-Chien Hsieh Julia Weng 《Applied Soft Computing》2012,12(10):3165-3175
This study presented a new diagnosis system for myocardial infarction classification by converting multi-lead ECG data into a density model for increasing accuracy and flexibility of diseases detection. In contrast to the traditional approaches, a hybrid system with HMMs and GMMs was employed for data classification. A hybrid approach using multi-leads, i.e., lead-V1, V2, V3 and V4 for myocardial infarction were developed and HMMs were used not only to find the ECG segmentations but also to calculate the log-likelihood value which was treated as statistical feature data of each heartbeat's ECG complex. The 4-dimension feature vector extracted by HMMs was clustered by GMMs with different numbers of distribution (disease and normal data). SVMs classifier was also examined for comparison with our system in experimental result. There were total 1129 samples of heartbeats from clinical data, including 582 data with myocardial infarction and 547 normal data. The sensitivity of this diagnosis system achieved 85.71%, specificity achieved 79.82% and accuracy achieved 82.50% statistically. 相似文献
133.
针对三宝钢铁有限公司电炉炼钢工艺发生变化,原有的除尘能力难以满足越来越高的环保要求,通过电炉除尘系统的改造和增设余热锅炉系统回收烟气余热产生蒸汽,不仅使得电炉除尘系统更高效、经济、环保,也提高了电炉炼钢能源循环利用。 相似文献
134.
Based on the stick-slip process, an effective method to extract the stress-strain curve directly from the crosshead displacement-load raw data in compression of bulk metallic glasses was proposed.The method was tested in two bulk metallic glass samples with different plasticities and shear band morphologies.The extracted stress-strain curves were found to well resemble the stress-strain curve measured by a laser ex-tensometer.In addition, the extracted curve could resolve fine structures of serrated flow much better than that measured by extensometer, thus facilitating the study of shear banding process.Results obtained by this method made the stick-slip dynamics of shear banding valid, and this method could be employed to obtain the real strain of small-sized metallic glass samples where extensometer cannot be applied. 相似文献
135.
Merat Hodaie Mirabdullah Seyed Sadjadi Mostafa M. Amini Ezzatollah Najafi Seik Weng Ng 《Journal of Inorganic and Organometallic Polymers and Materials》2016,26(3):500-511
In order systematically investigate the effect of ligand with a large conjugated π-system on the structure and optical properties of tin complex, anthracene-9-carboxylic acid (L1) is selected as a primary ligand, and quinoline-2-carboxylic acid (L2) used as second ligand to incorporate with anthracene-9-carboxylic acid to construct a new tin(IV)-carboxylate coordination complex under thermal gradient condition. Prepared complex was fully characterized based on its 1H and 13C NMR, IR and UV spectra and elemental analysis. The molecular structure of complex was determined by single-crystal X-ray analysis. The nanocrystalline complexes of the prepared complex were successfully obtained at 30, 50 and 60 °C by a facile sonochemical route. The new nanocrystalline complexes were characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and elemental analysis. The photoluminescence properties of the nanocrystalline complexes and crystalline bulk complex in the solid-state indicated that the size of the complex particles has a remarkable effect on the optical properties of it. Absorption and emission peaks of the nanocrystalline complexes blue shifted significantly in comparison with those of in the single-crystal form. Application of the prepared complex in fabrication of an organic light-emitting diode has been demonstrated. The current–voltage (I–V) characteristics and the electroluminescence (EL) properties of the complex have been investigated. The EL of the compound exhibits green emission at 552 nm. 相似文献
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137.
Abstract A computational algorithm is proposed for catalyst pellets or reactors experiencing concentration‐dependent deactivation. In the integration of the deactivation equation in each time interval, the concentration of poison, reactant or/and product is considered to be a constant. The value of concentration is recalculated from the mass balance equation before integrating the deactivation equation. By such an approach, the number of equations is reduced; thus a two‐dimensional problem can be converted to a single‐dimensional one. 相似文献
138.
This paper addresses the architecture and implementation of a medical drawing management system. The system enables physicians to draw directly on a patient picture or built-in anatomical templates of a body part. It contains modules for querying patient data and managing associated drawings including sketching, uploading, and sharing features. The system adapts to embed Windows-based applications into web pages; the web-based applications contain Windows-based graphical tools and enable seamlessly incorporating necessary drawing modules into the web-based healthcare information system at National Taiwan University Hospital. The system provides a web-based sketching capability that effectively support practitioners’ daily operations, as well as the use of paperless, digitizing patient records, and ultimately, will improve the overall quality of healthcare. 相似文献
139.
140.
In construction scheduling, problems can arise when each activity could start at different time points and the resources needed by the activities are limited. Moreover, activities have required conditions to be met, such as precedence relationships, resource requirements, etc. To resolve these problems, a two-phase GA (genetic algorithm) model is proposed in this paper, in which both the effects of time-cost trade-off and resource scheduling are taken into account. A GA-based time-cost trade-off analysis is adopted to select the execution mode of each activity through the balance of time and cost, followed by utilization of a GA-based resource scheduling method to generate a feasible schedule which may satisfy all the project constraints. Finally, the model is demonstrated using an example project and a real project. 相似文献