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21.
The problem of designing radar detection filters that minimise sidelobe levels in both Doppler and range co-ordinates is considered. The new algorithm for a Doppler optimised mismatch filter is constructed. The generalisation enables sidelobe suppression for the polyphase and complex multilevel sequences. For minimax filter coefficients calculation, the iterative reweighted least-square procedure is successfully applied. Favourable experimental results are obtained, especially for polyphase codes.<>  相似文献   
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The problem of mobile radio system outage in the presence of two signal third order intermodulation interferences is presented. The probability that the desired signal level exceeds the interference level by a predetermined value is defined, computed and graphically illustrated. For all signals the superposition of lognormal and Rayleigh distributions is assumed.<>  相似文献   
23.
Orthodontic patients experience pain and discomfort to a varying degree during the course of treatment. The aims of the present investigation were to follow the progress of adaptation after insertion of new appliances and to study the relationships between the type of appliance worn and pain or discomfort experienced, between pain sensations and attitude toward the treatment and their effects on patients' compliance. Pain and discomfort experienced by 84 patients undergoing orthodontic treatment, their attitude toward the treatment, and compliance were assessed 7 days, 14 days, 6 weeks, 3 months, and 6 months after appliance insertion, using specially designed protocols, questionnaires, and rating scales. Evaluation of the results showed that an adaptation to pain and discomfort occurred during the first 3 to 5 days after placement of the appliance. The severity of pain and discomfort experienced by the patients wearing functional or fixed appliances was significantly higher than by those treated with upper and/or lower removable plates. Patients who had higher personal perception of the severity of their malocclusion and displayed attitudes characteristic for internal control orientation according to the so-called locus of control theory, seemed to adapt faster and have less pain. The results of this study also indicate that acceptance of orthodontic appliances and treatment in general may be predicted by the amount of initial pain and discomfort experienced.  相似文献   
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PURPOSE AND METHODS: The aim of this study was to analyze clinical, radiologic, and histopathologic findings in 60 consecutive patients with medically intractable extratemporal epilepsy who were operated on between November 1987 and May 1993. RESULTS: Histologically, there were distinct structural abnormalities in 50 (83%) of the surgical specimens. Signal abnormalities on magnetic resonance imaging (MRI) were present in all patients with neoplastic lesions (n = 17) and in 94% of patients with nonneoplastic focal lesions (n = 32). Overall, structural abnormalities were detected by MRI in 47 (96%) of 49 patients with focal lesions. During a mean follow-up of 4 years, 30 (54%) patients remained completely seizure free, 11 (20%) had < or = 2 seizures per year, seven (12%) showed a seizure reduction of > or = 75%, and eight (14%) had < 75% reduction in seizure frequency. The fraction of seizure-free patients was 12 (80%) of 15 in patients with neoplastic lesions, 16 (52%) of 31 in patients with nonneoplastic focal lesions, and two (20%) of 10 for those without histopathologic abnormalities. The differences in seizure outcome between patients with and without focal lesions were statistically significant (p < 0.05), if seizure-free outcome was compared with persistent seizures. CONCLUSIONS: Focal lesions and particularly neoplasms are associated with improved postoperative seizure control compared with patients without histopathologic abnormalities. We advise caution in considering surgery to treat extratemporal epilepsy in patients who have normal MRI scans, because the outcome with the approach described in this study is poor in such cases.  相似文献   
25.
Glucosinolates are secondary metabolites of Brassica vegetables that have been associated with health benefits. The concentrations of these compounds are strongly affected by processing of the vegetables. Various mechanisms are responsible for these changes: Lysis of plant cells and compartments, diffusion and leaching of glucosinolates and myrosinase (a plant enzyme able to hydrolyze glucosinolates) into the cooking water, enzymatic hydrolysis of glucosinolates, inactivation of myrosinase and thermal degradation of glucosinolates. This publication presents a dynamic mathematical model that includes these mechanisms with their estimated parameters and the effect of temperature on them.Simulations made by the model for several process conditions show losses of glucosinolates as a consequence of domestic boiling of 69%, microwaving of 8%, industrial blanching of 37% and by industrial sterilization of 82%.The model can assist in adapting the processing conditions like the time–temperature profile and the vegetable–water ratio to optimize industrial and domestic processing of Brassica vegetables in terms of health benefits. In addition this model can help to add the effect of vegetable preparation practices on the quantitative glucosinolate intake in epidemiological studies.  相似文献   
26.
The essence of the conceptual design is getting the innovative projects or ideas to promise the products with best performance. It has been proved that the theory of inventive problem solution (TRIZ) is a systematic methodology for innovation. The design of a passively compliant robotic joint as an engineering example is illuminated in this paper to show the significance and approaches of applying TRIZ into getting the creative conceptual design ideas. In the robotic joints with passively compliance, the joints are composed of mechanical components such as springs and dampers as internal elements, which absorb the excessive collision force. Passive compliant joints with springs and dampers ensure a smooth contact with the surroundings, especially if robots are in contact with humans, but the passive compliant joints cannot determine precisely the position of the members of the joint or direction of the collision force. The main aim of this work is to show a systematic methodology for innovation as an effective procedure to enhance the capability of developing innovative passive compliant robotic joint and to overcome the main design problems. The TRIZ method will be utilized in order to eliminate the technical contradictions which appear in the passively compliant robotic joint.  相似文献   
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In this article, the authors report their experience with surgically induced supplementary motor area (SMA) deficiency syndrome in a prospective clinical trial of 28 patients who underwent surgery for tumorous (19 patients) or nontumorous (nine patients) lesions. The dominant side was affected in 17 patients and the nondominant side in 11 patients. The primary presenting symptoms included seizure activity (23 patients), hemiparesis (four patients), and aphasia (one patient). Functional topographic mapping, achieved by phase reversal of somatosensory evoked potentials, allowed precise localization of the central sulcus in 25 of the 28 patients. Motor evoked potential (MEP) monitoring, which was performed successfully in 13 of 15 cases during the resective procedure, showed no significant changes in the potentials in any patient. Immediately after surgery, 25 (89%) of the 28 patients displayed additional neurological deficits (aphasia and/or hemiparesis) that depended on the extent of the SMA resection. In 12 patients the SMA was resected completely: nine of these patients demonstrated a complete and three an incomplete deficit. In 16 patients the SMA resection was incomplete: 13 of these patients displayed an incomplete deficit, whereas three had no deficit. Neurological disorders resolved completely within 3 to 42 days (mean 11 days), except for a minimal disturbance of fine motor and/or speech function in complex tasks or at high speed. Electromagnetically elicited MEPs, examined postoperatively in five patients, were initially absent but recovered with improvement of motor function. In conclusion, although the SMA is known to control important functions such as initiation of motor activity or speech, our findings show that unilateral SMA removal can be accomplished without resulting in significant permanent deficits. Functional topographic mapping and monitoring facilitate the exact delineation of the adequate resection plane along the precentral sulcus, and postoperative magnetic resonance imaging allows precise correlation of clinical and anatomical data.  相似文献   
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The requirement for new flexible adaptive grippers is the ability to detect and recognize objects in their environments. It is known that robotic manipulators are highly nonlinear systems, and an accurate mathematical model is difficult to obtain, thus making it difficult то control using conventional techniques. Here, a novel design of an adaptive neuro fuzzy inference strategy (ANFIS) for controlling input displacement of a new adaptive compliant gripper is presented. This design of the gripper has embedded sensors as part of its structure. The use of embedded sensors in a robot gripper gives the control system the ability to control input displacement of the gripper and to recognize particular shapes of the grasping objects. Since the conventional control strategy is a very challenging task, fuzzy logic based controllers are considered as potential candidates for such an application. Fuzzy based controllers develop a control signal which yields on the firing of the rule base. The selection of the proper rule base depending on the situation can be achieved by using an ANFIS controller, which becomes an integrated method of approach for the control purposes. In the designed ANFIS scheme, neural network techniques are used to select a proper rule base, which is achieved using the back propagation algorithm. The simulation results presented in this paper show the effectiveness of the developed method.  相似文献   
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