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1.
We compare the recently proposed Discriminative Restricted Boltzmann Machine (DRBM) to the classical Support Vector Machine (SVM) on a challenging classification task consisting in identifying weapon classes from audio signals. The three weapon classes considered in this work (mortar, rocket, and rocket‐propelled grenade), are difficult to reliably classify with standard techniques because they tend to have similar acoustic signatures. In addition, specificities of the data available in this study make it challenging to rigorously compare classifiers, and we address methodological issues arising from this situation. Experiments show good classification accuracy that could make these techniques suitable for fielding on autonomous devices. DRBMs appear to yield better accuracy than SVMs, and are less sensitive to the choice of signal preprocessing and model hyperparameters. This last property is especially appealing in such a task where the lack of data makes model validation difficult.  相似文献   
2.
The effects of interactions between nonlinear subprocesses on the stabilizability of plantwide systems via the concept of dissipative systems are studied. Conditions for which controlled variables of each interconnected subprocess can be driven to and maintained at their desired values are established through the application of interconnection decoupling techniques. The resulting decoupling feedback law encodes the interaction effects between subprocesses and determines the required information structure for achieving desired control performance using distributed control laws. The proposed constructive approach leads to new criteria for the selection of manipulated and controlled variables that guarantee plantwide stability. © 2013 American Institute of Chemical Engineers AIChE J, 59: 2795–2809, 2013  相似文献   
3.
This paper develops an efficient approach to modeling and analyzing the overall dynamics of polydisperse particulate systems, exemplified using a rotating drum with horizontal axis, under both constant and time-varying operating conditions. This approach captures the collective dynamics using stochastic models in the form of Markov chains. The characteristics of such dynamics can be obtained from the Markov chains operator. It provides a systematic way to the analysis of collective dynamical features of particle movements. The obtained operators are used to estimate the spatial particle distribution and the degree of particulate mixing as examples of collective dynamic features of polydisperse particulate systems. In this paper, Markov chains models were developed from discrete element method simulation results to show the effectiveness of the proposed approach.  相似文献   
4.
Thermodynamic and Experimental Study of the Mg-Sn-Ag-In Quaternary System   总被引:1,自引:0,他引:1  
Phase equilibria in the Mg-rich region of the Mg-Sn-Ag ternary system were determined by quenching experiments, differential scanning calorimetry, electron probe micro-analysis, and X-ray diffraction techniques. No ternary compounds were found in the studied isothermal sections. A critical evaluation of the available experimental data and a thermodynamic optimization of the Mg-Sn-Ag-In quaternary system were carried out using the calculation of phase diagrams method. The modified quasichemical model in the pair approximation was used for the liquid solution, which exhibits a high degree of short-range order. The solid phases were modeled with the compound energy formalism. All available and reliable experimental data were reproduced within experimental error limits. A self-consistent thermodynamic database was constructed for the Mg-Sn-Ag-In quaternary system, which can be used as a guide for Mg-based alloys development.  相似文献   
5.
Lobster waste (including the head and hard carapace, viscera, mandibles and gills) contains approximately 54 μg/g total astaxanthin, 29% protein, 23% chitin, 34% ash and 2.2% crude fat on a dry weight basis. Trypsin from bovine pancreas was applied to facilitate the recovery of carotenoid pigments and protein as carotenoprotein complex, which was subsequently air‐dried to a stable powder form at 45°C and 15% relative humidity. The product obtained was found to contain 60% protein, 15% crude fat, 6% ash, 8% chitin and 295 μg/g total astaxanthin. Thus, the process achieved a substantial reduction in the levels of anti‐nutrients associated with lobster waste (i.e., ash and chitin) while elevating the levels of carotenoid pigments and essential nutrients such as protein and fat in the recovered product These characteristics of the final product suggest that it could be used as an inexpensive source of pigment and protein in diets of cultured salmonid species.  相似文献   
6.
OBJECTIVES: To evaluate the value of concomitant coronary endarterectomy (CE) in the modern era of coronary revascularization. METHODS: Retrospective study. Twenty-eight patients (five women; 23 men) who underwent coronary endarterectomy were angiographically studied 24 +/- 22 months after the procedure. Necessity CE (vessel completely occluded or with lumen less than 1 mm) was performed on the left anterior descending (LAD) artery in 12 patients, the right coronary artery (RCA) in nine, the obtuse marginal artery (OM) in five and a diagonal branch in two patients. Conduits used for revascularization were the internal thoracic artery (ITA) in 11 (all anastomosed to the LAD; combined with saphenous vein patch in four) and a saphenous vein graft in 17 patients. Mean atherosclerotic core length was 3.3 +/- 1.8 cm. An average of 3.1 +/- 0.7 distal anastomoses per patient were constructed, with mean aortic cross-clamp and cardiopulmonary bypass times of 61.2 +/- 20.2 mins and 94.0 +/- 23.5 mins, respectively. RESULTS: Overall, angiographic patency rate was 71% (20 of 28) for the endarterectomized vessels (12 of 12 LAD, six of nine RCA, two of five OM and none of two diagonal arteries) and 93% (57 of 61) for the nonendarterectomized vessels. Among the eight patients with occluded CE vessels, two sustained a perioperative myocardial infarction, five developed angina during follow-up, and one patient remained asymptomatic. CONCLUSION: Necessity CE demonstrates acceptable mid-term patency. In addition, this study showed excellent patency following CE of the LAD revascularized with the ITA, with or without only a saphenous vein patch.  相似文献   
7.
Several common sources of discharges activity occurring on generators have been replicated in the laboratory under well-controlled conditions. Each source was evaluated individually and recorded with a phase resolved acquisition system and with a spectrum analyzer. The dominant features of each respective phase resolved partial discharge (PRPD) pattern are presented. The frequency content of the discharge signal at the detection coupler was also investigated. The association of each well-defined type of discharge source, with its specific PRPD pattern, constitutes the basis of our database used for the discharge source recognition during generator diagnostics. The comparison of laboratory results with actual field measurements gathered over the last decade is summarized.  相似文献   
8.
This article demonstrates that, before the 19th century and the Paris Clinical School, new medical practice and new clinical teaching based on pathological anatomy (of organs and of tissues) and surgical experience and therapeutic experimentation developed in the military milieu, specifically because of the "auspicious" conditions found there. Over time, this military clinical experience permeated civilian medical practice as military practitioners often moved into civilian practice and collaborated and exchanged experience with their civilian or ex-military colleagues. These conditions, in different forms and at different rhythms, in the great European powers, also favoured a rapprochement between the different groups of medical practitioners--physicians, apothecaries and surgeons--initially in the military milieu, and subsequently in civilian society as well. Finally, the article shows that the coercive disciplinary structure of the military, where sick or wounded soldiers were particularly constrained to act as subjects of experience, experimentation, clinical teaching and anatomico-pathological research, was one of the conditions propitious to this growth of clinical practice.  相似文献   
9.
The phase diagrams of the LiAlSi2O6‐MgSiO3 and LiAlSi2O6‐CaMgSi2O6 isopleths were experimentally investigated at 1 atm using the quenching method and differential scanning calorimetry and the phases produced were characterized with the help of X‐ray diffraction and electron probe microanalysis. With the help of thermodynamic optimization, the phase diagrams of both systems were more accurately reported. No detectable solubility of Li2O in diopside and enstatite was found. However, both systems are not simple binary eutectic systems because their phase equilibria are somewhat complex due to the presence of some β‐spodumene solid solution. In the β‐spodumene solid solution, no notable solubility of MgO and CaO was detected; evidence of significant solubility of SiO2 was confirmed.  相似文献   
10.
A time-series (1990–2013) of classified vegetation cover maps was produced for Netley-Libau Marsh, a 26,000 ha coastal wetland on Lake Winnipeg, to assess its current status and verify earlier trends of emergent vegetation loss. Open water area in the marsh was measured from late-summer Landsat images for 20 years; three classes of vegetation types (emergents, wet meadows, upland) could also be identified for 12 images covering the same period. Temporal changes in area and distribution of marsh vegetation were related to adjoining Lake Winnipeg water-level and Red River discharge, as well as marsh connectivity and bathymetry. From 1990 to 2002, an increase in open-water areas and decrease in emergent vegetation coincided with rising levels and flows. The year 2003 marked major wetland regeneration and a decrease of open-water area under extremely low water-levels and flows. From 2005 to 2013, open-water area remained consistent, under high but variable levels and flows. A strong negative correlation was found between area of emergent vegetation and mean Red River discharge in the previous June-July. Superimposition of the limit of new emergent vegetation observed in 2003 with depth contours surveyed in 2010 revealed the dynamic nature of marsh bathymetry. Periods of extremely low water as short as one year (2003) induced a marked expansion in emergent vegetation cover that persisted over the next ten years despite higher water-levels. Rather than being gradual, changes in the spatial extent of Netley-Libau Marsh vegetation appeared to proceed by fits and starts, wherein periods of relative stasis were disrupted by major changes in abundance.  相似文献   
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