Analog circuits need more effective fault diagnosis methods. In this study, the fault diagnosis method of analog circuits was studied. The fault feature vectors were extracted by a wavelet transform and then classified by a generalized regression neural network (GRNN). In order to improve the classification performance, a wolf pack algorithm (WPA) was used to optimize the GRNN, and a WPA-GRNN diagnosis algorithm was obtained. Then a simulation experiment was carried out taking a Sallen–Key bandpass filter as an example. It was found from the experimental results that the WPA could achieve the preset accuracy in the eighth iteration and had a good optimization effect. In the comparison between the GRNN, genetic algorithm (GA)-GRNN and WPA-GRNN, the WPA-GRNN had the highest diagnostic accuracy, and moreover it had high accuracy in diagnosing a single fault than multiple faults, short training time, smaller error, and an average accuracy rate of 91%. The experimental results prove the effectiveness of the WPA-GRNN in fault diagnosis of analog circuits, which can make some contributions to the further development of the fault diagnosis of analog circuits.
Due to the characteristics of color vegetation canopy images which have multiple details and Gaussion noise interference, the adaptive mean filtering (AMF) algorithm is used to perform the denoising experiments on noised images in RGB and YUV color space. Based on the single color characteristics of color vegetation canopy images, a simplified AMF algorithm is proposed in this paper to shorten the overall running time of the denoising algorithm by simplifying the adaptive denoising processing of the component V, which contains less image details. Experimental results show that this method can effectively reduce the running time of the algorithm while maintaining a good denoising effect.
Artykuł ma na celu omówienie nieurzędowych nazw miejscowych jako form odmiennych od nazw oficjalnych, analizę ich cech strukturalnych i semantycznych oraz wskazanie ich historycznego świadectwa. Nieurzędowe chińskie nazwy miejscowe, „przezwiska miejscowe” czy „nazwy pochwalne miast” nie powinny być definiowane jako nietypowe i nieformalne, ponieważ obecnie są one w Chinach bardzo popularne i wykorzystuje się je w sytuacjach formalnych. Są one nadawane przede wszystkim ważnym jednostkom miejskim, zyskującym społeczne uznanie. Większość z nich jest skonstruowana z dwóch członów. Człon pierwszy to człon odróżniający, a człon drugi to człon generyczny czy utożsamiający. Człony generyczne to terminy: ‘miasto’, ‘stolica’, ‘rzeka’, ‘góra’, ‘wyspa’ itp., a człony odróżniające nawiązują do roślin, zwierząt, minerałów, produktów lokalnych itp. Chińskie „nazwy pochwalne miast” są wykorzystywane przy różnych okazjach, mają zróżnicowaną dystrybucję i różny poziom stabilności. W artykule omówiono tylko część z nich, te o stosunkowo wysokiej częstości użycia, znacznej stabilności i wyraźnej akceptacji społecznej.
This article explores investment protection under Chinese international investment agreements (IIAs), particularly under the China-Poland bilateral investment treaty (BIT). As a state that both imports and exports foreign direct investment, China currently promotes balanced and safeguarded BITs that protect its increasing overseas investments and preserves the necessary space to regulate in the public interest. The Chinese government remains reluctant to be directly involved in investment arbitration as a respondent, while Chinese investors are active in taking advantage of the IIAs’ regime. When compared to China’s recent treaty practice and new developments in global investment governance, the China-Poland BIT is relatively outdated in terms of investment protection, promotion, social clauses, and dispute settlement. In terms of the investment protection effects of BITs, China is seemingly in a more urgent position to update the China-Poland BIT. However, if we evaluate the overall effects of a modernized BIT on investment promotion, regulation, and dispute settlement, an updated China-Poland BIT will fit the interests of both the Polish and Chinese governments. Notwithstanding the on-going negotiation between the EU and China, this article aims, along with presenting the Chinese practice regarding BITs, to describe de lege lata the state of protection offered to Chinese and Polish investors under the China-Poland BIT.
The head-related transfer function (HRTF) is dependent on the position of the sound source (both direction and distance) and is also affected by individual anatomical parameters. Individualized HRTFs have been shown to affect the perception of sound direction, but have not been considered in distance perception. This work aims to discover, by means of psychoacoustic experiments for a virtual reproduction system through a pair of in-ear headphones, the effect of individualized HRTF on auditory distance perception for a nearby sound source. The individualized HRTFs of six subjects and the non-individualized HRTFs of a mannequin at seven distances between 0.2 and 1.0 m and five lateral azimuths between 45X and 135X in the horizontal plane were processed with white noise to generate binaural signals. Further, the individualized and non-individualized HRTFs were used in the auditory distance perception experiments. Results of distance perception show that the variance of distance perception results among subjects is significant, the reason could be the stimuli are lack of dynamic cue and early reflections, or the auditory difference of distance perception among subjects. However, via the analyses of mean slope of perceptual distance and correlation between the perceptual and real distance, we find that the individualized HRTF cue has insignificant influence on distance perception.
Wave motion in pipe bends is much more complicated than that in straight pipes, thereby changing considerably the propagation characteristics of guided waves in pipes with bends. Therefore, a better understanding of how guided waves propagate in pipe bends is essential for inspecting pipelines with bends. The interaction between a pipe bend and the most used non-dispersive torsional mode at low frequency in a small-bore pipe is studied in this paper. Experiments are conducted on a magnetostrictive system, and it is observed that T(0,1) bend reflections and mode conversions from T(0,1) to F(1,1) and F(2,1) occur in the pipe bend. The magnitude of the T(0,1) bend reflections increases with increasing propagation distance and excitation frequency. The amplitude of the mode-converted signals also increases with increasing propagation distance, but it decreases with increasing excitation frequency. Because of their longer bent path, the test signals for a pipe bend with a bending angle of 180X are much more complicated than those for one with a bending angle of 90X. Therefore, it is even more difficult to scan a bent pipe with a large bending angle. The present findings provide some insights into how guided waves behave in pipe bends, and they generalize the application of guided-wave inspection in pipelines.
A spinal code is the type of rateless code, which has been proved to be capacity- achieving over both a binary symmetric channel (BSC) and an additive white Gaussian noise (AWGN) channel. Rateless spinal codes employ a hash function as a coding kernel to generate infinite pseudo-random symbols. A good hash function can improve the perfor- mance of spinal codes. In this paper, a lightweight hash function based on sponge structure is designed. A permutation function of registers is a nonlinear function. Feedback shift registers are used to improve randomness and reduce bit error rate (BER). At the same time, a pseudo-random number generator adopts a layered and piecewise combination mode, which further encrypts signals via the layered structure, reduces the correlation between input and output values, and generates the piecewise random numbers to compensate the shortcoming of the mixed linear congruence output with fixed length. Simulation results show that the designed spinal code with the lightweight hash function outperforms the original spinal code in aspects of the BER, encoding time and randomness.
Ti-containing steel weld metals with Al contents of 0.01-0.085% were prepared. The effects of Al contents on the inclusions evolution were investigated by means of thermodynamic calculations coupled with electron probe micro-analyses and transmission electron microscopy. The results show that the inclusions in the 0.01% Al weld metal are mainly composed of ilmenite with some amounts of (Mn-Si-Al)-oxide and titanial_spinel. When Al content is increased up to 0.035%, a more amount of corundum and a small amount of pseudobrookite are formed. In 0.085% Al weld metal, the (Mn-Si-Al)-oxide disappears completely, and the inclusions contain a substantial amount of corundum, in addition to a minimal amount of pseudobrookite. Ti3O5, MnTi2O4 and MnTiO3 are the primary constituents of pseudobrookite, titanial_spinel and ilmenite, respectively. Titanial_spinel and ilmenite have higher amounts of Mn, but lower Ti levels compared with pseudobrookite. In the case of presence of a considerable amounts of titanial_spinel and ilmenite, Mn-depleted zone is formed in matrix around the inclusions.
Acoustical analysis of snoring provides a new approach for the diagnosis of obstructive sleep apnea hypopnea syndrome (OSAHS). A classification method is presented based on respiratory disorder events to predict the apnea-hypopnea index (AHI) of OSAHS patients. The acoustical features of snoring were extracted from a full night’s recording of 6 OSAHS patients, and regular snoring sounds and snoring sounds related to respiratory disorder events were classified using a support vector machine (SVM) method. The mean recognition rate for simple snoring sounds and snoring sounds related to respiratory disorder events is more than 91.14% by using the grid search, a genetic algorithm and particle swarm optimization methods. The predicted AHI from the present study has a high correlation with the AHI from polysomnography and the correlation coefficient is 0.976. These results demonstrate that the proposed method can classify the snoring sounds of OSAHS patients and can be used to provide guidance for diagnosis of OSAHS.