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991.
A neural fuzzy resource manager for hierarchical cellular systems supporting multimedia services 总被引:1,自引:0,他引:1
Kuen-Rong Lo Chung-Ju Chang Shung C.B. 《Vehicular Technology, IEEE Transactions on》2003,52(5):1196-1206
Using intelligent techniques to perform radio resource management is an effective method. The paper proposes neural fuzzy control for radio resource management in hierarchical cellular systems supporting multimedia services. A neural fuzzy resource manager (NFRM) is designed, which mainly contains a neural fuzzy channel allocation processor (NFCAP). The NFCAP has a two-layer architecture: a fuzzy cell selector (FCS) in the first layer and a neural fuzzy call-admission and rate controller (NFCRC) in the second layer. The FCS chooses not only the handoff failure probabilities and the resource availabilities in both microcell and macrocell, but also the user mobility, as input linguistic variables. The NFCRC takes the handoff failure probability and the resource availability of the selected cell as input variables to perform call admission control and rate control for the call. Simulation results show that the NFRM can always guarantee the quality of service (QoS) requirement for handoff failure probability for all traffic loads. Also, the NFRM improves the system utilization by 31.1% while increasing the handoff rate by 2% over the overflow channel allocation (OCA) scheme; it enhances the system utilization by 6.3% and 1.4%, and still reduces the handoff rate by 14.9% and 6.8%, as compared to the combined channel allocation (CCA) and fuzzy channel allocation control (FCAC) schemes, respectively, under a predefined QoS constraint. 相似文献
992.
OBJECTIVES: To find the incidence of brucellosis, and analyse its epidemiological characteristics and the evolution of the cases recorded in the Sierra de Cádiz Primary Care (PC) Area during 1992. DESIGN: A prospective longitudinal incidence analysis, with a nested study of cases and controls. SETTING: Sierra de Cádiz PC Area. PATIENTS AND OTHER PARTICIPANTS: Cases: members of the cohort who developed the disease. Controls: sample of members of the cohort free of Brucellosis paired for age, gender and town of origin. MEASUREMENTS AND MAIN RESULTS: Incidence was 52.39 per 100,000, 66.27 and 38.20 per 100,000 in men and women, respectively. Highest incidence was at between 15 and 49 years of age (67.70 per 100,000). Cases in the Spring predominated (chi 2 = 16.77, gl = 3, p < 0.05). The most affected professional group was farmers/herders (RR = 4.59, CI 95%, 2.05-10.26). CONCLUSIONS: The Sierra de Cádiz is an area with endemic brucellosis, especially in the districts of Olvera and Ubrique. Its work-related character is clear, in spite of the digestive tract being the main transmission path. 相似文献
993.
The development of the IEEE wireless technologies is promising the ultimate Internet service deployment on wireless and mobile infrastructures since they would offer larger bandwidth at cheaper price. However, it is disquieting to see that the different control algorithms supposed to be the heart of the wireless deployment are not evolving as fast as the wireless technologies do. Here we come up with the hard question: how to pilot these control algorithms? This paper is proposing a revolutionary tyre where all control algorithms are fed in a concerted manner by a self-steering system. In network terms, this paper is proposing a definitely new technology that will permit to optimize, secure, manage and control the wireless devices using an automatic pilot system. 相似文献
994.
Rad A.B. Chan P.T. Wai Lun Lo Mok C.K. 《Industrial Electronics, IEEE Transactions on》2003,50(5):1016-1021
A fuzzy controller with online learning capability is reported in this paper. The controller learns from a standard proportional plus derivative (PD) controller. It is implicitly assumed that the tuning parameters of the PD controller are already known. The learning is realized via Wang's table lookup scheme. The controllers are applied successfully to control an open-loop unstable system, i.e., the ball and plate system. Experimental studies have demonstrated the performance of the proposed controller. 相似文献
995.
Biocompatible and mechanical properties of low temperature deposited quaternary (Ti, Al, V) N coatings on Ti6Al4V titanium alloy substrates 总被引:1,自引:0,他引:1
D. M. Grant W. J. Lo K. G. Parker T. L. Parker 《Journal of materials science. Materials in medicine》1996,7(9):579-584
A series of quaternary (Ti, Al, V) N coating layers were obtained by low temperature reactive plasma sputtering in differing deposition conditions to improve the wear resistance and the biocompatibility of a titanium surgical alloy, specifically Ti-6Al-4V. Characterization of the mechanical properties, structure and the chemical composition of the coating layer was explored by microhardness test, ball against flat wear test, scanning electron microscopy and X-ray diffraction. The biocompatibility of the optimum coating layer (as determined by mechanical performance) was examined by a modified MTT toxicity test and by monitoring cell growth assessed by quantitative stereological analysis. The experimental results are encouraging, indicating that this low temperature deposited, dense, quaternary (Ti, Al, V) N coating layer exhibits improved mechanical properties such as high hardness and excellent adhesion to a Ti alloy substrate and is highly biocompatible. 相似文献
996.
BACKGROUND/AIMS: The hypothesis that profound acid suppression might prevent clot lysis and thus benefit patients with a non-bleeding visible vessel has not been confirmed. Omeprazole can suppress gastric acid remarkably and may be beneficial for patients with peptic ulcer bleeding. METHODOLOGY: Fifty-two patients with a non-bleeding visible vessel at the ulcer base were enrolled and randomized into four groups (N = 13 in each group). In the cimetidine group, the patients received cimetidine 300 mg i.v. bolus followed by 300 mg i.v. every 6 hr during hospitalization. In the heater probe thermocoagulation + cimetidine group, the patients received heater probe thermocoagulation and cimetidine 300 mg i.v. bolus followed by 300 mg i.v. every 6 h during hospitalization. In the omeprazole q.d. group, the patients received omeprazole 40 mg i.v. bolus followed by 40 mg i.v. daily for two days. In the omeprazole q 12 h group, the patients received omeprazole 40 mg i.v. bolus followed by 40 mg i.v. every 12 h for two days. A 24 hr intragastric pH was recorded for every case. RESULTS: The mean 24 hr intragastric pH were higher in the omeprazole q.d. (mean 5.8) and the omeprazole q 12 h groups (mean 6.4) than in the cimetidine (mean 4.3) and the heater probe thermocoagulation + cimetidine groups (mean 4.9) (p < 0.05). Rebleeding occurred in 5, 2, 2 and 2 patients in the cimetidine, heater probe thermocoagulation + cimetidine, omeprazole q.d., and omeprazole q 12 h groups, respectively (p > 0.05). Volume of blood transfusion and number of days in hospital were not statistically different among the four groups. CONCLUSIONS: Omeprazole can remarkably suppress gastric acid when it is compared to that of the H2 receptor blocker. Patients with a non-bleeding visible vessel using omeprazole do not exhibit a decrease in the rebleeding rate as compared with those patients using cimetidine. 相似文献
997.
Yu Lo Cyrus Chang Lander L.C. Horng-Shing Lu Wells H.T. 《Reliability, IEEE Transactions on》1994,43(3)
The authors propose a simple and practical probabilistic model, using multiple incomplete test concepts, for fault location in distributed systems using a Bayes analysis procedure. Since it is easier to compare test results among processing units, their model is comparison-based. This approach is realistic and complete in the sense that it does not assume conditions such as permanently faulty units, complete tests, and perfect or nonmalicious environments. It can handle, without any overhead, fault-free systems so that the test procedure can be used to monitor a functioning system. Given a system S with a specific test graph, the corresponding conditional distribution between the comparison test results (syndrome) and the fault patterns of S can be generated. To avoid the complex global Bayes estimation process, the authors develop a simple bitwise Bayes algorithm for fault location of S, which locates system failures with linear complexity, making it suitable for hard real-time systems. Hence, their approach is appealing both from the practical and theoretical points of view 相似文献
998.
SL Wang WH Pan CM Hwu LT Ho CH Lo SL Lin YS Jong 《Canadian Metallurgical Quarterly》1997,40(12):1431-1438
Our aim is to determine non-insulin-dependent diabetes mellitus (NIDDM) incidence in Taiwan and examine its relation to obesity and hyperinsulinaemia in Chinese men and women. A total of 995 men and 1195 women aged 35-74 years free from diabetes in two townships in Taiwan were followed up with a second examination. At baseline general and metabolic data were recorded, and detailed anthropometric parameters and plasma glucose and insulin were assessed. World Health Organisation (WHO) criteria of fasting glucose 7.8 mmol/l or greater was utilized for defining diabetes. The age-standardized incidence rate based on the United States population in 1970 was 9.3/1000 (CI 5.8-12.8) in men and 9.3/1000 (CI 6.2-12.4) in women and the based on the WHO population in 1976 was 8.9/1000 (CI .5-12.3) in men and 8.9/1000 (CI 5.9-11.9) in women for the Chinese who had a mean BMI slightly greater than 24 (kg/m2). The predictability of the plasma glucose level was greater than that of the insulin level and the obesity indices. NIDDM incidence increased approximately threefold with each 0.67 mmol/l increase in plasma glucose level in men and women. The present study demonstrated the essential relationship of not only BMI but also central obesity indices (such as subscapular and waist circumference) to the incidence of NIDDM among men and women and a stronger relationship between NIDDM incidence and obesity in women than in men. The predictive effects of obesity indices and fasting plasma insulin values on NIDDM risk were independent of each other in men. Obesity and hyperinsulinaemia each without the presence of the other can lead to an increased risk of NIDDM. In women the NIDDM incidence increased more than additively in those with both obesity and hyperinsulinaemia compared to those with single obesity or hyperinsulinaemia. A slightly higher incidence of NIDDM in Taiwan than in western countries was found. The importance of obesity is indicated for predicting NIDDM in the community. Hyperinsulinaemia was found to play a significant role in predicting NIDDM incidence independent of obesity in men and synergistically with obesity in women. 相似文献
999.
L Cominacini MM Young A Capriati U Garbin A Fratta Pasini M Campagnola A Davoli A Rigoni GB Contessi V Lo Cascio 《Canadian Metallurgical Quarterly》1997,40(10):1211-1218
The oxidative modification of low density lipoprotein is of importance in atherogenesis. Antioxidant supplementation has been shown, in published work, to increase low density lipoprotein resistance to oxidation in both healthy subjects and diabetic subjects; in animal studies a contemporary reduction in atherogenesis has been demonstrated. Troglitazone is a novel oral antidiabetic drug which has similarities in structure with vitamin E. The present study assessed the effect of troglitazone 400 mg twice daily for 2 weeks on the resistance of low density lipoprotein to oxidation in healthy male subjects. Ten subjects received troglitazone and ten received placebo in a randomised, placebo-controlled, parallel-group design. The lag phase (a measure of the resistance of low density lipoprotein to oxidation) was determined by measurement of fluorescence development during copper-catalysed oxidative modification of low density lipoprotein. The lag phase was increased by 27 % (p < 0.001) at week 1 and by 24% (p < 0.001) at week 2 in the troglitazone treated group compared with the placebo group. A number of variables known to influence the resistance of low density lipoprotein to oxidation were measured. They included macronutrient consumption, plasma and lipoprotein lipid profile, alpha-tocopherol, beta-carotene levels in low density lipoprotein, low density lipoprotein particle size, mono and polyunsaturated fatty acid content of low density lipoprotein and pre-formed low density lipoprotein hydroperoxide levels in low density lipoprotein. Troglitazone was associated with a significant reduction in the amount of pre-formed low density lipoprotein lipid hydroperoxides. At weeks 1 and 2, the low density lipoprotein hydroperoxide content was 17% (p < 0.05) and 18% (p < 0.05) lower in the troglitazone group compared to placebo, respectively. In summary the increase in lag phase duration in the troglitazone group appeared to be due to the compound's activity as an antioxidant and to its ability to reduce the amount of preformed low density lipoprotein lipid hydroperoxides. This antioxidant activity could provide considerable benefit to diabetic patients where atherosclerosis accounts for the majority of total mortality. 相似文献
1000.
M Lospalluti F Barile AK Pantaleo M Conese AP Guerra M Lo Re G D'Amico G Barbieri 《Canadian Metallurgical Quarterly》1994,144(2):129-138
In the above double-blind multicenter study the efficacy and tolerability of 50 and 100 mg doses of fluconazole were compared with 100 mg itraconazole in 178 patients with T. corporis, T. cruris, and T. pedis infections. All patients were submitted to clinical and mycological examination before starting, at weekly intervals during treatment, and 4 and 8 weeks after its conclusion. Duration of the three therapeutic regimes was 15 days for T. corporis and T. cruris, and 30 days for T. pedis infection. The percentage of symptomatic cure was 85% and 86.5%, respectively for 50 and 100 mg fluconazole, and 83% for itraconazole. Mycologic cure was achieved in 81.4% of patients treated with 50 mg fluconazole, 83.3% in those treated with 100 mg fluconazole, and 67.9% in those treated with 100 mg itraconazole. None of the groups showed changes in laboratory parameters. It is concluded that all three treatment schemes had high antimycotic activity, but fluconazole both 50 and 100 mg daily was superior. Both drugs were well tolerated and compliance was good. 相似文献