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The accurate estimation of the fundamental matrix is one of the most important steps in many computer vision applications such as 3D reconstruction, camera self-calibration, motion estimation and stereo matching. In this paper, an optimal fundamental matrix estimation method based on removing exceptional match points is proposed. Firstly, the initial mismatch is reduced by the bidirectional SIFT feature matching algorithm. Secondly, the partial concentration problem of random samples is solved by the bucket segmentation method. In order to obtain robustness, the fundamental matrix is estimated in a RANSAC framework according to the principle of minimizing the geometric distance. Finally, the iterate process improves the accuracy of the fundamental matrix by using the LM algorithm. Experimental results show that the proposed method can reduce the outlier’s interference better and improve the estimation precision of the fundamental matrix.

Based on the requirement of small errors in measuring roundness (cylindricity) error, a leveling methodology which using a dual-point vertical layout has been put forward and analyzed. According to the direction cosine of the axis of workpiece, the amount of leveling has been defined and calculated, which overcomes the problem brought by manual adjustment technology and forms theoretical bases of fast, accurate leveling and high precise measurement. The assessment of roundness (cylindricity) error is to search for a center (cylinder axis) which satisfies the minimum condition. Due to the reliance of initial solutions and relative slowness in terms of convergence precision and convergence rate when using Nelder-Mead simplex method, a combinative method of Quasi-Newton and N-M simplex method has been proposed which achieves a fast, accurate search for global optimums. With the proof of the simulation of classical testing functions using Matlab and the measured data, the convergence rate and precision will be enhanced effectively has been certified with the combination of both methods mentioned above which ensuring and improving the measuring precision of workpiece.

In order to improve the scalability and reliability of Software Defined Networking (SDN), many studies use multiple controllers to constitute logically centralized control plane to provide load balancing and fail over. In this paper, we develop a fexible dormant multi-controller model based on the centralized multi-controller architecture. The dormant multi-controller model allows part of controllers to enter the dormant state under light traffc condition for saving system cost. Meanwhile, through queueing analysis, various performance measures of the system can be obtained. Moreover, we analyze the real traffic of China Education Network and use the results as the parameters of computer simulation and verify the effects of parameters on the system characteristics. Finally, a total expected cost function is established, and genetic algorithm is employed to find the optimal values of various parameters to minimize system cost for the deployment decision making.

According to Wiener-Khintchine theorem, autocorrelation function of an image was proved that can be used as sharpness evaluation function. An image sharpness index k is proposed and the relationship between content of high frequency components of an image and the width d of its autocorrelation function main lobe was constructed through Fourier transformation. The direct ration relationship between the sharpness index k of an image and the width d of its autocorrelation function main lobe was also validated by experiments. Theoretical analysis and experiment results indicate that d increases when an image is blurry and d decreases when the image is clear.

Ignition energy of aviation ignition equipment is an important parameter for reliable launch of air jet. The factors are quite more that influence ignition energy and increasing the charge voltage of capacitance with high efficiency is an approach which increasing ignition energy efficiently. The charge voltage is the output voltage of switching power of ignition device. A mathematic model was constructed for switching power, and a mathematic expression were deduced about output voltage uo with input voltage ui and other elements parameters of switching power supply. An important conclusion were obtained which uo mainly depended on input voltage ui, load RL, dynatron collector peak current ICM on certain condition through a smart transform. When increasing ui, RL, ICM , uo increasing observably. The PSpice circuit simulation software is used for simulation, and the results show that the above conclusion is valid and feasible.

Enquiry into a marginally subnormal hemogram in two adolescents with complex conduct, dysthymic and movement disorders uncovered a striking iron deficiency and prompted a trial of replacing psychotropic medication with iron therapy. The rationale of iron therapy for behavioural disturbance was examined from the clinical, neurochemical and psychopharmacological points of view. Although further study is required to confirm the therapeutic efficacy and to define the precise nature of iron deficiency in conduct disorder, the weight of the evidence suggests that correcting the nutrient deficit may be an essential step toward a refinement of therapeutic strategies. The presence of a borderline hemogram, hypermenorrhea and malnutrition should alert clinicians to the possibility of iron deficiency, and laboratory screening for hypoferremia should be considered when assessing conduct disorder.

The concentration of serotonin (5-HT) and 5-hydroxyindole acetic acid (5-HIAA) in various body fluids was measured during the perinatal period in two groups of infants born with normal and pathological conditions, respectively. Evidence was obtained showing that fetal blood 5-HT level was relatively stable, uninfluenced by maternal or fetal factors, and was about half the value of the maternal blood. High levels of 5-HIAA and evidence of an active decomposition of 5-HT were found in the amniotic fluid. These findings suggest that 5-HT in uterois subjected to a very active metabolic turnover. The origin of the fetal blood 5-HT and the significance of the placenta in the control of intrauterine 5-HT metabolism is discussed. There was no clear evidence of abnormal 5-HT metabolism in toxemic pregnancies, premature babies, and an infant with Down’s syndrome in the perinatal period.

This study surveyed psychiatric problems treated with psychotropic medication among mentally handicapped at five regional centres in Eastern Ontario. Of the 2,158 residents studied, 920 (43%) were identified as problem cases, ranging from 36% to 83% in different institutions. Aggressivity, hyperactivity, and self-injury are the most prevalent conditions among more than thirty problem categories. Analysis of multidimensional contingency tables revealed that each of these three problems is involved with a distinct pattern of interactions with the set of demographic and clinical variables. The diversity of these interaction patterns points out the inadequacy of any unitary hypothesis of the pathogenesis and the inadvisability of adopting over-generalized treatment modalities. It is proposed that rational planning of service should rely on a realistic estimation of individuals’ needs and a better understanding of the scope and nature of the problem.

Severe visual disturbance associated with lesions of the optic nerve developed in a Wilson's disease patient who had been receiving DL-penicillamine therapy for more than 2 years. Prompt relief was achieved with pyridoxine hydrochloride. These results suggest that the optic nerve lesions resulted from a penicillamine-induced pyridoxine deficiency. Furthermore, results of urinary xanthurenic acid excretion studies made on the patient before and after tryptophan loading tests, which were conducted during periods of no therapy, penicillamine therapy, and penicillamine plus pyridoxine therapy, indicate an alteration in pyridoxine metabolism in the presence of penicillamine. Although no other similar cases have been described, the present results indicate the possibility that patients on prolonged high dosage levels of penicillamine may require pyridoxine supplementation of their diet.

Software-Defined Networking (SDN) is now considered as one of the promising future networking technologies, and this trend can be clearly verified by observing activities of both industry and academia. In industry, we can easily notice that many major network vendors, such as Cisco and Juniper, are actively supporting SDN functionalities. In addition, several network service provides have deployed SDN enabled networks service provides have deployed SDN enabled networks in their services (e.g., Google B4 and Microsoft SWAN). This trend can also be noticeable in academia. Recently, many SDN related research outputs have been published and announced at diverse top tier networking venues (e.g., SIGCOMM, CoNEXT, and NSDI). As such, SDN is now a key player in networking, and thus it is clear that we, researchers, should put more attention on this area.

The influence of Al+++Substitution for Fe+++in M-type Ba ferrite on the magnetocrystalline anisotropy field HAand the critical single-domain radius Rchas been studied by Haneda and Kojima. It is difficult to obtain HcJvalues agreeing with theoretical results for the reason that the HcJis very sensitive to the preparation method. We have been developing a new method called "coprecipitation combined with high-temperature melting." It offers a suitable condition for studying the rule of HcJof Ba Fe12-xAlxO19. Our results conformed to the effects calculated by Haneda and Kojima. The highest level of HcJin our experiment reached 16000 Oe. We have fabricated plastic sheet magnets from the superhigh HcJferrite powder and padded the soft ferrite core with this sheet magnet to adjust the bias magnetic field. This ferrite core can be improved and the weight and size of the device can be reduced.