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51.
This paper is concerned with the stability analysis problem for a class of delayed stochastic recurrent neural networks with both discrete and distributed time-varying delays. By constructing a suitable Lyapunov–Krasovskii functional, a linear matrix inequality (LMI) approach is developed to establish sufficient conditions to ensure the global, robust asymptotic stability for the addressed system in the mean square. The conditions obtained here are expressed in terms of LMIs whose feasibility can be checked easily by MATLAB LMI Control toolbox. In addition, two numerical examples with comparative results are given to justify the obtained stability results.  相似文献   
52.
This paper presents our work towards developing a new speech corpus for Modern Standard Arabic (MSA), which can be used for implementing and evaluating Arabic speaker-independent, large vocabulary, automatic, and continuous speech recognition systems. The speech corpus was recorded by 40 (20 male and 20 female) Arabic native speakers from 11 countries representing three major regions (Levant, Gulf, and Africa). Three development phases were conducted based on the size of training data, Gaussian mixture distributions, and tied states (senones). Based on our third development phase using 11 hours of training speech data, the acoustic model is composed of 16 Gaussian mixture distributions and the state distributions tied to 300 senones. Using three different data sets, the third development phase obtained 94.32% and 8.10% average word recognition correctness rate and average Word Error Rate (WER), respectively, for same speakers with different sentences (testing sentences). For different speakers with same sentences (training sentences), this work obtained 98.10% and 2.67% average word recognition correctness rate and average WER, respectively, whereas for different speakers with different sentences (testing sentences) this work obtained 93.73% and 8.75% average word recognition correctness rate and average WER, respectively.  相似文献   
53.
This paper addresses the issue of reliable feedback control of an uncertain aircraft flight control systems with disturbances via non-fragile sampled-data control approach. In particular, the parameter uncertainties are assumed to be randomly occurring which is described by the Bernoulli distributed sequences. By constructing a suitable Lyapunov–Krasovskii functional together with Wirtinger-based inequality, a new set of sufficient conditions in terms of linear matrix inequalities is obtained to ensure the asymptotic stability and extended dissipativity of the aircraft flight control systems not only when all actuators are operational, but also in case of some actuator failures. Finally, simulation results are conducted to validate the effectiveness of the proposed control design technique.  相似文献   
54.
55.
Serum alpha-1-antitrypsin assay was carried out in 21 smokers (mean age 44±8 yrs) and in 25 nonsmokers (mean age 44±7 yrs). The levels of serum alpha-1-antitrypsin expressed in umol/mt/ml were 2.97±0.85 for smokers and 3.08±0.37 for non-smokers and analysis of variance revealed no significant difference between these two groups. However in five smokers reduced levels (<80% of the lower limit of non-smokers) were seen and four of them were bus drivers. This study advises monitoring of serum alpha-1-antitrypsin levels in smokers with possible therapy to those with reduced levels.  相似文献   
56.
Urinary iodine was estimated chemically by the kinetic method, after mineralisation of the organic iodide by alkaline ashing. The experimental conditions were optimised. The methodological modifications of an existing technique are highlighted. Urinary iodine levels were determined in 349 school children of Bombay, of whom 163 had Grade IA/IB/II goitre and the remaining 186 did not have goitre. Urinary iodine concentration (Mean±SEM) of the control (n=186) and the goitre (n=163) groups were 76.47±4.97 and 71.09±6.23 μg/g creatinine respectively. The difference in the means was statistically not significant. Urinary iodine exhibited a log-normal distribution. It is concluded that the presence of goitre in the clinically euthyroid group of children was not caused by iodine deficiency.  相似文献   
57.
Appropriate therapeutic measures can improve the life expectancy of patients with ovarian malignancy. There has been a pressing need for serodiagnostic assays to enable, the close patient monitoring. Cancer Antigen 125 (CA125) has been described as a useful marker in patient monitoring for ovarian malignancy. Keeping this in view, the present study was planned. 40 consecutive female patients of ovarian carcinoma (mean age 52.4±10.7 years) were selected for serum CA125 analysis during the period of year 1995–2001. The tumour marker concentration was compared with histologic types of ovarian tumour and the FIGO staging of the disease. 25 healthy females (mean age 35.2–10.4 years) served as control. Mean serum CA125 concentrations in patients with papillary serous adenocarcinoma(Mean±%CV 1571±121.5 U/ml) was much higher than patients with mucinous adenocarcinoma(775±78U/ml). Mean serum CA125 concentration in endometrioid carcinoma was very high(2853±136 U/ml). The patient with clear cell carcinoma however had shown moderate increase(60 U/ml). No correlation was found between serum CA125 concentration and the FIGO staging of disease. Quantitation of CA125 was most helpful in monitoring the response of treatment and followup of the patients after completion of their treatment. Posttherapeutically its concentration showed more than 50% reduction in almost all (91.4%) patients (P<0.001). Importantly these patients had also shown significant regression of the disease clinically and radiologically. 8.6% of patients had shown static or increase in serum CA125 concentration which was associated with either clinically static or progressive disease. Recurrence of the disease was noted in patients who had shown increase in serum CA125 concentration (biochemical recurrence) in the followup However, in our test population biochemical recurrence(increase in serum marker concentration) preceded the clinical or radiological recurrence by an average of 6.5 months. Kaplan meier survival analysis for evaluation of overall survival in our test subjects showed an overall survival of 32% at one year and median survival of 9 months with confidence interval of 6.34 to 11.66. We conclude that serum CA125 is a useful marker for monitoring the treatment and predicting an early recurrence of the disease in ovarian carcinoma patients. A study in larger number of patients is needed to define its exact role in the management of the carcinoma ovary.  相似文献   
58.
This study aimed to investigate whether treadmill versus overground soccer match simulations have similar effects on knee joint mechanics during side cutting. Nineteen male recreational soccer players completed a 45-min treadmill and overground match simulation. Heart rate (HR) and rating of perceived exertion (RPE) were recorded every 5 min. Prior to exercise (time 0 min), at “half-time” (time 45 min) and 15 min post-exercise (time 60 min), participants performed five trials of 45° side-cutting manoeuvres. Knee abduction moments and knee extension angles were analysed using two-way repeated measures analysis of variance (α = 0.05). Physiological responses were significantly greater during the overground (HR 160 ± 7 beats ? min?1; RPE 15 ± 2) than the treadmill simulation (HR 142 ± 5 beats ? min?1; RPE 12 ± 2). Knee extension angles significantly increased over time and were more extended at time 60 min compared with time 0 min and time 45 min. No significant differences in knee abduction moments were observed. Although knee abduction moments were not altered over time during both simulations, passive rest during half-time induced changes in knee angles that may have implications for anterior cruciate ligament injury risk.  相似文献   
59.
Early Childhood Education Journal - During the COVID-19 pandemic, most countries took precautionary steps to save their citizens by initiating a lockdown and stopping all social activities by...  相似文献   
60.
Historically low average pass rate has been a perennial challenge for the universities and provincialised colleges in the North-Eastern states of India (Assam, Meghalaya, Mizoram, Nagaland, Tripura, Manipur and Arunachal Pradesh). Pass rate refers to the proportion of students promoted from one semester to the next and also the proportion of students who pass the final examination to be a graduate. The paper attempts to trace the key parameters for quality improvement for higher education in the region and subsequently augment the pass rate. An inductive content analysis was conducted based on focus group interviews at various levels at Assam University, Silchar and its affiliated provincialised colleges. The four broad categories thus identified (academic, administrative, socio-economic and placement issues) were subjected to Pareto 80-20 principle to identify the issues that are to be given priority for evolving the system. The study would help the administrators to measure the quality of higher education system in a hostile environment characterised by adverse topography, political disturbances, skewed distribution of income, widespread poverty and lack of literacy.  相似文献   
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