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Road recognition is a very important link in the safe driving of vehicles. In this paper, a region based road recognition method is proposed for infrared road images. Noise is eliminated by mean filtering and threshold segmentation. Then, the road boundary segments are obtained by the threshold exhaustive method, and the road boundary segments are obtained by the second-order differential operator. The road boundary segments obtained by the two methods are fused to obtain the candidate road boundary segments. Finally, the real road boundary is obtained by optimising the line fitting. For the identified road, the moving target tracking based on interacting multi-mode Kalman filter is adopted. The simulation results show that the interacting multimode Kalman filter can achieve better trajectory fitting, and the errors in X and Y directions before and after filtering are small. This shows the excellent performance of interacting multimode Kalman filter in moving target detection.

As chlorpyrifos is used globally to control pests in sugarcane fields, analysis of its residues on food crops is essential to assess product safety for humans. In this study, chlorpyrifos content in sugarcane plants, soil and juice was determined using a gas chromatography with an electron capture detector. The limit of quantification was 0.01 mg/kg for plant and soil, and 0.01 mg/L for juice. The degradation and residual risk in sugarcane fields after applying chlorpyrifos to two sample sites (Changsha and Danzhou, China) were assessed. Chlorpyrifos concentrations in plants and soil decreased rapidly over time, reaching a degradation rate ranging from 98.82 to 99.25% on day 35. The half-life of chlorpyrifos in both plants and soil was only 5.97-6.12 days. Regardless of application dosage (standard or high) at a pre-harvest interval of 60 days, chlorpyrifos was undetectable in the harvested sugarcane. Risk assessment indicated that chlorpyrifos residue in sugarcane did not pose a health risk to humans.

One of the most important ways to enhance the speed of state estimation is to establish the constant matrix Jacobian. This essay puts forward the state estimation method of the equivalent current transformation based on the Generalized Tellegens Theorem. This estimation method establishes the constant Jacobian matrix without neglecting the secondary factor making use of the Generalized Tellegens Theorem, solves the numerical stability problem caused by the establishment of the constant Jacobian matrix in the current state estimation, and has the advantages of a relatively rapid computing rate, making advantage of measuremnt of WAMS and SCADA system, and an unparalleled astringency. The method put forward in this essay has been verified through IEEE-30 Node System, and the efficiency of it has been fully proved by the example results.

Two new briarane metabolites—fragilides K (1) and L (2)—along with five known analogues—gemmacolide X, praelolide, juncins P and ZI, and gemmacolide V (3–7)—were extracted and purified from Junceella fragilis, a gorgonian coral. Based on data obtained via spectroscopic techniques, the structures of new briaranes 1 and 2 were determined and the cyclohexane rings in 1 and 2 were found to exist in chair and twist boat conformation, respectively. Additionally, anti-inflammatory analysis showed that briaranes 2, 3, and 6 inhibited pro-inflammatory inducible nitric oxide synthase protein expression and briaranes 3 and 7 suppressed the cyclooxygenase-2 level, in LPS-stimulated murine macrophage-like RAW264.7 cells.

A new type of combined ecological floating bed was developed on Swan Lake. It was combined with aquatic and hydrophilous plants and ancillary equipments that included floating controllers, water-cycling aerator systems and wave-making systems. Combined ecological floating bed changed the physical and chemical environment of Swan Lake and had an effect on the transportation and transformation of TN, NH4(+) -N and TP between overlying water and sediment during the experiment. The concentration change of TN, NH4(+) -N and TP and the effect of DO, Eh and pH on the nutrient in the overlying water and sediment were investigated. The results indicated that: in overlying water, the removal efficiencies of TN, NH4(+) -N and TP were 61.92%, 63.09% and 80.0%, respectively; the removal efficiencies of TN and NH4(+) -N were 23.79% and 37.04%, respectively; the concentration of TP increased by 43.71% in sediment during the experiment. The combined ecological floating bed influenced environmental factors such as DO, Eh and pH in overlying water in some degree. DO concentration rose from 8.7-8.9 mg x L(-1) to 9.3-10.4 mg x L(-1), and Eh concentration was from 163-178 mV to 191-198 mV. Both of them were higher than those in the contrast area. Phosphorus release was inhibited, and phosphorus adsorption was promoted through improving DO and Eh of the overlying water. The pH volatility was less and maintained between 7.51 and 8.32, and did not promote phosphorus release in sediment. TN, TP and NH4(+) -N in overlying water and TN and NH4(+) -N in sediment were significantly positively correlated with each other and with TP in sediment. The pH had no significant correlation with TN, TP and NH4(+) -N in overlying water and sediment. DO was significantly positively corrected with Eh in overlying water and was significantly negatively corrected with TP in sediment.

A clustering algorithm based selective neural networks ensemble (CLUSEN) is proposed to predict the degree of malignancy in brain glioma. Since the degree prediction of malignancy is critical before brain surgery, many learning methods are used like rule induction algorithm, single neural networks, support vector machines, etc. Ensemble learning methods can improve the generalization of single learning machine, and are becoming popular in the machine learning and medical data processing communities. The procedure of CLUSEN can efficiently remove redundancy learning individuals and help improve the diversity of ensemble methods. CLUSEN is used to predict the degree of malignancy in brain glioma. Experimental results on a set of brain glioma data show that, compared to support vector machines, rule induction and single neural networks, the classification accuracy of CLUSEN is higher.

Based on the double-injection effect, the dual-mode interference principle and the free-carrier plasma dispersion effect, a double-injection bifurcation optical active switch integrated on silicon-on-insulator has been proposed and fabricated. Its insertion loss and crosstalk are measured to be less than 5.32 and -14.4 dB, respectively, at wavelength 1.3 μm and the total switching current 90 mA. Response time is about 180 ns.

By means of CUSP model of catastrophe theory, this paper has studied the physics process of rockburst occurred on circular chamber. The present paper has not only described the instability process of rockburst more deeply, but also got the critical depth of plastic softening area of chamber that is valuable in the controlling engineering of rockburst. The chamber displacement jump and energy liberation have been derived. The influence of rock parameters on the rockburst has been discussed.

Based on the large cross-section single-mode rib waveguide condition, the total internal reflection and the free-carrier plasma dispersion effect, a silicon-on-insulator (SOI) 2 × 2 symmetric optical waveguide switch with a transverse injection structure has been proposed and fabricated, in which the SOI technique utilizes silicon and silicon dioxide thermal bonding and back-polishing. The device performance is measured at the wavelength of 1.3 μm. It shows that the crosstalk and insertion loss are less than - 18.1 and 4.8 dB, respectively, at an injection current of 60 mA, and response time is 110 ns.

To investigate the relation between various risk factors and benign prostatic hyperplasia (BPH).A population based case-control study was conducted, including 100 BPH patients over 60 years old living in suburb of Shenyang as study group, and 100 elderly men with non-BPH (excluding prostatic cancer and prostatitis) as control group. Chi(2) test and non-conditional logistic regression were used for monovariate analysis and multivariate analysis, respectively.Data from monovariate analysis showed that BPH incidence was significantly related to body weight index, cigarette smoking, alcohol drinking, meal intake at the beginning of 1980's, hypertention and prostatitis, respectively. While multivariate non-conditional logistic analysis showed that BPH was related to five factors: prostatitis (OR = 5.577, 95% CI: 2.147 - 14.482), monthly intake of meats at the beginning of 1980's (OR = 4.930, 95% CI: 2.404 - 10.111), diastolic blood pressure (OR = 1.050, 95% CI: 1.017 - 1.083), cigarette smoking (OR = 0.660, 95% CI: 0.500 - 0.872) and alcohol consumption (OR = 0.650, 95% CI: 0.480 - 0.881).Prostatitis, monthly excessive intake of meats at the beginning of 1980's and high diastolic blood pressure were possible risk factors for BPH, while heavy cigarette smoking and alcohol consumption were possible protective factors for BPH.

Superconducting microbridge has high sensitivity and low noise. We have successfully developed High Tc superconducting detector of microbridge structure with area of 10/spl times/20 /spl mu/m. At 500 K, its responsitivity is R=8.9/spl times/10/sup 4/ v w/sup -1/, the detectivity D* is 4.5/spl times/10/sup 10/ cm H/sub z//sup 1/2/ w/sup -1/. Using such a detector, we have detected submillimeter wave and millimeter wave. For wavelength of 3 mm, the achieved responsitivity R is 6.01/spl times/10/sup 2/ v w/sup -1/ and detectivity D* is 6.1/spl times/10/sup 8/ cm H/sub z//sup 1/2/ w/sup -1/. Our work has opened a new way to use this kind of detector.

Semiconductor optical switches utilizing carrier-induced refractive index change have tremendous potential for the application of optical processing because of their small size , single-mode operation , polarizationindependence and wavelength-insensitivity. These switches are generally based on total internal reflection , and have a requirement of precise control of reflection interface1, 2. The requirement causes a difficulty in developing silicon switches of the same kind. Because silicon is an indirect-gap semiconductor , the injected carriers in it diffuse a long distance due to their long lifetime. They can not be restricted within a specific region in the normal structure like what has been taken in InGaAsP or A1GaAs. Although some authors have reported that attempt to make use of the free-carrier effect in silicon for optical switching, the developed switches are all based on mode-interference other than internal reflection3, 4. These switches are devoid of the advantages mentioned above. From the viewpoint of practical application , a kind of silicon switch with these advantages is more essential.

Based on the top seeded infiltration and growth technique (TSIG), a novel configuration was employed to fabricate single-domain Gd-Ba-Cu-O (GdBCO) bulk superconductors. And the morphology, microstructure, and superconducting properties of the products were investigated in detail. The results indicate that, employing the novel configuration can increase the supporting ability of the liquid source pellet, and the slope or collapse of the sample during the heat treatment process can be effectively avoided, thus the stability and repeatability of the experiments are advanced. In addition, the novel configuration also contributes to the complete growth of the whole bulk.

Effects of additional permanent magnet on the levitation force of a single domain GdBCO bulk superconductor have been investigated with a cylindrical permanent magnet in their coaxial configuration under zero field cooled state at liquid nitrogen temperature. The magnetic polarity N of cylindrical permanent magnet is pointed to the GdBCO bulk superconductor, and the two additional permanent magnet of rectangular parallelepiped shape are fixed on two sides of the GdBCO bulk superconductor in different arrangments. It was found that the levitation force can be improved to about 61.5 N, which is more than 2 times higher than that (29.8 N) of the system without the additional permanent magnet, when the magnetic polarity N of two additional permanent magnets points to the GdBCO bulk superconductor in horizontal direction. The levitation force is reduced to 19.6N, which is about 65.8% of the levitation force 29.8N of the system without the additional permanent magnets, when the magnetic polarity N of two additional permanent magnet are antiparallel to the magnetic polarity N of the cylindrical permanent magnet. The results indicate that the levitation force of high temperature bulk superconductors can be effectively improved by introducing additional permanent magnet based on reasonably designing the system configuration, which is very important during the practical design and applications of superconducting magnetic levitation systems.

Three new kinds of liquid source were prepared by mixing R2O3 (here R is Gd,Y or Yb respectively),BaCuO2 and CuO powders. Single-domain Gd-Ba-Cu-O bulk superconductors have been fabricated using these liquid sources by the top seeded infiltration and growth technique. The growth characteristic and microstructure of the samples have also been investigated in detail. The results indicate that, employment of the new liquid sources not only can help us reduce the experimental period and improve the fabrication efficiency, but also can be used to fabricate well-textured single domains. Additionally, using the liquid source mixed by Y2O3 or Yb2O3 can raise the utilization rate of the liquid source powders, as well as contribute to the refinement of Gd-211 particles in the molten liquid.

Mechanism of irradiation effects is analyzed for floating gate read only memorie s (ROMs). Phenomena in experiments are reasonably explained. It is proposed that failures in devices result from oxide trapped charge and interface trapped char ge generated by radiation in memory cells and peripheral circuitry. The neutron, proton and 60Co γ irradiation effects in FLASH ROM and EEPROM a re total dose effects.