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991.
Intelligent optimal control with dynamic neural networks. 总被引:2,自引:0,他引:2
The application of neural networks technology to dynamic system control has been constrained by the non-dynamic nature of popular network architectures. Many of difficulties are-large network sizes (i.e. curse of dimensionality), long training times, etc. These problems can be overcome with dynamic neural networks (DNN).In this study, intelligent optimal control problem is considered as a nonlinear optimization with dynamic equality constraints, and DNN as a control trajectory priming system. The resulting algorithm operates as an auto-trainer for DNN (a self-learning structure) and generates optimal feed-forward control trajectories in a significantly smaller number of iterations. In this way, optimal control trajectories are encapsulated and generalized by DNN. The time varying optimal feedback gains are also generated along the trajectory as byproducts. Speeding up trajectory calculations opens up avenues for real-time intelligent optimal control with virtual global feedback.We used direct-descent-curvature algorithm with some modifications (we called modified-descend-controller-MDC algorithm) for the optimal control computations. The algorithm has generated numerically very robust solutions with respect to conjugate points. The adjoint theory has been used in the training of DNN which is considered as a quasi-linear dynamic system. The updating of weights (identification of parameters) are based on Broyden-Fletcher-Goldfarb-Shanno BFGS method. Simulation results are given for an intelligent optimal control system controlling a difficult nonlinear second-order system using fully connected three-neuron DNN. 相似文献
992.
Akbayir O Gedikbasi A Akyol A Numanoglu C Koroglu N Gulkilik A 《The journal of obstetrics and gynaecology research》2011,37(8):1126-1131
Benign cystic mesothelioma (BCM) is a rare tumor of unknown origin, most frequently encountered in women of reproductive age and with unknown etiology. Most patients have a history of previous pelvic operation, endometriosis, or pelvic inflammatory disease. Preoperative diagnosis is difficult. We report the cases of three patients, with one case complicated by pregnancy, and discuss the diagnostic evaluation and treatment of this rare disease. Complete surgical resection is recommended if feasible. However, recurrent disease is not uncommon. Clinical positive effects of different adjuvant medical treatments are also discussed. 相似文献
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Iskeleli G Bilgeç MD Arici C Atalay E Oğreden T Aydin A 《The Turkish journal of pediatrics》2011,53(6):692-694
Richner-Hanhart syndrome (tyrosinemia type II) is a rare autosomal recessive disease associated with high serum tyrosine levels caused by the deficiency of tyrosine aminotransferase enzyme. We report a 15-year-old female patient with complaints of bilateral photophobia and tearing, which started during the infancy period. Biomicroscopic examination revealed bilateral circular corneal opacities on the inferior quadrant and small dendritic lesions at the center of the circular opacities. Blood tests showed a tyrosine level of 508 micromol/L (normal range: 30-150). On her dermatologic examination, plantar hyperkeratosis and seborrheic dermatitis were noted, and mild mental retardation was detected. One and a half months after the tyrosine- and phenylalanine-restricted diet, her tyrosine level dropped to 395 micromol/L level, her corneal lesions subsided, and a symptomatic relief was achieved. Tyrosinemia type II should be suspected in patients demonstrating dermatologic signs, especially palmoplantar keratosis, associated with bilateral pseudodendritic corneal lesions unresponsive to antiviral therapy. 相似文献
996.
Senturk N Aydin F Haciomeroglu P Yildiz L Totan M Canturk T Turanli AY 《Pediatric dermatology》2004,21(6):660-663
Lupus vulgaris is reinfection tuberculosis of the skin and may result from direct extension, or hematogenous or lymphatic spread from a tuberculosis focus. Lupus vulgaris following bacille Calmette-Guerin (BCG) vaccination is a rare entity. Incontinentia pigmenti is an X-linked dominant genodermatosis in which vesicular, verrucous, and pigmented lesions are associated with various developmental defects. There is evidence of altered immunologic reactivity in some patients with incontinentia pigmenti. A 12-year-old girl hospitalized for pulmonary tuberculosis presented with bizarre-shaped brown macules following Blaschko lines on the left deltoid area, compatible with incontinentia pigmenti, which had appeared following BCG vaccination at the age of 7 years. Histopathologic examination found noncaseated granulomas in the dermis. Antituberculous treatment for pulmonary and cutaneous tuberculosis was initiated along with genetic counseling. Immunologic abnormalities have been reported in conjunction with incontinentia pigmenti. Simultaneous occurrence of pulmonary and cutaneous tuberculosis in our patient might be either coincidental or indicate derangements in the cellular immune system. 相似文献
997.
Akar A Orkunoglu FE Ozata M Sengul A Gur AR 《European journal of dermatology : EJD》2004,14(3):156-158
Vitamin D receptor (VDR) is expressed in the hair follicle and the lack of it leads to alopecia. In this study, we investigated whether there was a relationship between VDR FokI gene polymorphism and alopecia areata (AA). This is the first study investigating the relationship between VDR gene polymorphism and AA. Twenty-five patients with the extensive forms of AA (alopecia totalis; AT, alopecia universalis; AU and AT/AU) and 27 healthy control subjects were genotyped. Their genotypes were determined by a polymerase chain reaction (PCR) and restriction fragment length polymorphism analysis. The genotypes were classified as FF (absence of the FokI site) and ff (presence of the FokI site). Allele frequencies for F and f alleles were 76.0% and 24.0% in the alopecic group and 72.2% and 27.7% in the control group (p > 0.05). The frequencies for the FF, Ff and ff genotypes were 56.0%, 40.0% and 4.0% in the patient group, and 48.1%, 48.1% and 3.7% in the control group, respectively. No statistically significant differences were observed in the frequencies of the VDR FokI genotype between the patient and the control groups. However, to conclude that there is no relationship between VDR gene polymorphism and AA, the VDR FokI polymorphism should be further studied in other populations, larger groups, and the distribution of other VDR polymorphisms such as BsmI, Tru9I, ApaI, TaqI and polyA. 相似文献
998.
Guleser Umit Yasar Sarici Ahmet Murat Ucar Didar Gonen Busenur Sengul Samanci Nilay Özgüroğlu Mustafa 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2022,260(4):1337-1343
Graefe's Archive for Clinical and Experimental Ophthalmology - To compare the efficacies of iodine-125 brachytherapy (IBT) and gamma knife stereotactic radiosurgery (GKRS) in the treatment of... 相似文献
999.
Grayanotoxin is a naturally occurring sodium channel toxin which enters the human food supply by honey made from the pollen and nectar of the plant family Ericaceae in which rhododendron is a genus. Grayanotoxin/mad honey poisoning is a little known, but well studied, cholinergic toxidrome resulting in incapacitating and, sometimes, life-threatening bradycardia, hypotension, and altered mental status. Complete heart blocks occur in a significant fraction of patients. Asystole has been reported. Treatment with saline infusion and atropine alone is almost always successful. A pooled analysis of the dysrhythmias occurring in 69 patients from 11 different studies and reports is presented. The pathophysiology, signs, symptoms, clinical course, and treatment of grayanotoxin/mad honey poisoning are discussed. In the nineteenth century grayanotoxin/mad honey poisoning was reported in Europe and North America. Currently, documented poisoning from locally produced honey in Europe or North America would be reportable. Possible reasons for this epidemiologic change are discussed. 相似文献
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