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This paper proposes a WD-GA-LSSVM model for predicting the displacement of a deep-seated landslide triggered by seasonal rainfall, in which wavelet denoising (WD) is used in displacement time series of landslide to eliminate the GPS observation noise in the original data, and genetic algorithm (GA) is applied to obtain optimal parameters of least squares support vector machines (LSSVM) model. The model is first trained and then evaluated by using data from a gentle dipping (~2°-5°) landslide triggered by seasonal rainfall in the southwest of China. Performance comparisons of WD-GA-LSSVM model with Back Propagation Neural Network (BPNN) model and LSSVM are presented, individually. The results indicate that the adoption of WD-GA-LSSVM model significantly improves the robustness and accuracy of the displacement prediction and it provides a powerful technique for predicting the displacement of a rainfall-triggered landslide.

Ray-tracing method is used to investigate the light extraction efficiency (LEE) of Bragg diffraction-assisted GaN-based light-emitting diodes (LED's) with vertical sidewalls. The ray tracing is based on the analytical formulae of the LEE in the incoherent regime for LED model with infinite lateral size. It is shown that without considering the sidewalls, the change of the LEE with the absorption or backside reflectivity is too small and thus not reasonable. And the enhancement with respect to the unpatterned case could be overestimated by ignoring the finite-size effect. Numerical calculations show that the enhancement of the LEE due to the sidewalls when compared to the infinite model could be up to 10% or even higher. Besides, the extracted energy from the sidewalls decreases due to the increased extraction from the PhC when compared to the unpatterned LED. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

In this paper we mainly study the derivations for even part of the finite-dimensional odd Hamiltonian superalgebra HO over a field of prime characteristic. We first give the generating set of the even part $$ \mathfrak{g} $$ of HO. Then we compute the derivations from $$ \mathfrak{g} $$ into the even part $$ \mathfrak{M} $$ of the generalized Witt superalgebra. Finally, we determine the derivation algebra and outer derivation algebra of g and the dimension formulas. In particular, the first cohomology groups H 1( $$ \mathfrak{g} $$ ; $$ \mathfrak{M} $$ ) and H 1( $$ \mathfrak{g} $$ ; $$ \mathfrak{g} $$ ) are determined.

The embedding theorem is established for ℤ-graded transitive modular Lie superalgebras \(\mathfrak{g} = \oplus _{ - 1 \leqslant i \leqslant r} \mathfrak{g}_i \) satisfying the conditions: (i) \(\mathfrak{g}_0 \simeq \tilde p(\mathfrak{g}_{ - 1} )\) and \(\mathfrak{g}_0 \)-module \(\mathfrak{g}_{ - 1} \) is isomorphic to the natural \(\tilde p(\mathfrak{g}_{ - 1} )\)-module; (ii) \(\mathfrak{g}_{ - 1} = \tfrac{2}{3}n(2n^2 + 1)\), where \(n = \tfrac{1}{2}\) dim \(\mathfrak{g}_{ - 1} \).

A 206 ∼ 220 GHz varactor-free voltage-controlled oscillator (VCO) is proposed to improve the output power and tuning range. The topology of the VCO is push-push crosscoupled pair. By using body-bias technique, the parasitic capacitor of the cross-coupled pair can be adjusted, and the varactors in the conventional VCO design can be removed. The proposed VCO was designed and implemented in TSMC 65-nm CMOS technology with a chip size of 0.25 × 0.25 mm2. The tuning range is 6.6% (from 206.2 to 220 GHz). The measured phase noise is −66 dBc/Hz at 1 MHz offset frequency. The output power is 1.3 dBm at 216 GHz with 54-mW dc power consumption and its maximum dc-to-RF efficiency is 2.1%. To the best of our knowledge, this varactor-free VCO achieves the highest dc-to-RF efficiency among published CMOS VCOs around 200 GHz.

This paper reports the morphometric analysis results of 100 cases of bladder tumor cells with a Q-900 computer-assisted image analysis system. According to the nuclear area, axis ratio and area ratio of tumor nuclei, bladder transitional cell tumors were divided into 4 grades. This system is called the morphometric grading system (M grading). The results show that the higher the M grading, the lower the survival rate and the higher the recurrence rate. As the M grade increases the tumors could be accompanied by muscular invasion. When recurring, the tumor has a poor prognosis if M grading increases. We conclude that the morphometric grading system is able to yield a quantitative pathologic diagnosis and can predict the biological behavior of bladder tumors. Recently, new techniques for diagnosing and predicting the biological behavior of bladder tumors have been developed. One such technique is morphometric analysis of bladder transitional cell carcinoma with computer-assisted image instruments [1]. Because this morphometric method is easily applicable to pathological section routinely stained with HE and the results are reproducible and more objective, the studies about morphometric analysis of bladder tumor have increased in recent times. This paper reports the preliminary morphometric analysis results of bladder tumor cells examined by a Q-900 image analysis instrument for 100 cases.

The hot-carrier stress effects on the high-frequency performance characteristics of laterally diffused metal–oxide–semiconductor (LDMOS) transistors were investigated. A constant bias channel hot-carrier stress was applied at room temperature. After applying 3 h of hot-carrier stress, the on-resistance and saturation drain current degradations are 18 and 9%, respectively. However, the degradations of the cutoff frequency and maximum oscillation frequency were less than 2% when the devices were biased before the onset of quasi-saturation. In addition, we found that the degradations of high-frequency parameters are not related to the change in transconductance but to the changes in gate capacitances. Finally, S-parameter variations under hot-carrier stress were also examined in this study. The observations of S-parameter variations are important for RF power amplifier design.

The natural filtrations of the general algebra W and the special algebra S of formal vectorfields are proved to be invariant. Furthermore, the automorphism groups of W and S are proved to be isomorphic to the corresponding admissible automorphism groups of the base superalgebra U. Then the automorphisms of W or S can be induced by the continue automorphisms of U.