低压台区拓扑信息的准确记录是进行台区线损分析、三相不平衡治理等工作的基础。针对目前拓扑档案排查成本高且效率低的问题,提出一种基于自适应k近邻(adaptive k nearest neighbor,AKNN)异常检验和自适应密度峰值(adaptive density pea...低压台区拓扑信息的准确记录是进行台区线损分析、三相不平衡治理等工作的基础。针对目前拓扑档案排查成本高且效率低的问题,提出一种基于自适应k近邻(adaptive k nearest neighbor,AKNN)异常检验和自适应密度峰值(adaptive density peaks clustering,ADPC)聚类的低压台区拓扑识别方法。该方法利用动态时间弯曲(dynamic time warping,DTW)距离度量低压台区用户间电压序列的相似性,通过AKNN异常检验算法检验并校正异常的用户与变压器之间的关系(简称“户变关系”),在得到正确户变关系的基础上,采用ADPC聚类算法对台区内用户进行相位识别;最后,通过实际台区算例分析验证了该方法不需要人为设置参数,能有效实现低压台区的拓扑识别,具有较高的适用性与准确性。展开更多
Ethyl methane-sulfonate (EMS)-mutagenized Arabidopsis M-2 populations were screened in low-K+ medium using the root-bending assay. Forty-two putative low-k(+)-tolerant (lkt) mutants were selected from 150 000 tested M...Ethyl methane-sulfonate (EMS)-mutagenized Arabidopsis M-2 populations were screened in low-K+ medium using the root-bending assay. Forty-two putative low-k(+)-tolerant (lkt) mutants were selected from 150 000 tested M-2 seedlings, and two of these mutants maintained their low-K+-tolerant phenotype in their M-3 generations, respectively. Genetic analysis showed that either one of these two mutants has a monogenic recessive mutation in a nuclear gene, and that the two mutations in two independent mutants are allelic to each other.展开更多
The changes in external K^＋ concentration affect plant root growth. However, the molecular mechanism for perceiving a K^＋ signal to modulate root growth remains unknown. It is hypothesized that the K^＋ channel AKTI...The changes in external K^＋ concentration affect plant root growth. However, the molecular mechanism for perceiving a K^＋ signal to modulate root growth remains unknown. It is hypothesized that the K^＋ channel AKTI is involved in low K^＋ sensing in the Arabidopsis root and subsequent regulation of root growth. Along with the decline of external K^＋ concentration, the primary root growth of wild-type plants was gradually inhibited. However, the primary root of the akt1 mutant could still grow under low K^＋（LK） conditions. Application of NAA inhibited akt1 root growth, but promoted wild-type root growth under LK conditions. By using the ProDR5：GFP and ProPIN1：PIN1-GFP lines, we found that LK treatment reduced auxin accumulation in wild-type root tips by degrading PIN1 proteins, which did not occur in the akt1 mutant. The LK-induced PIN1 degradation may be due to the inhibition of vesicle trafficking of PIN1 proteins. In conclusion, our findings indicate that AKT1 is required for an Arabidopsis response to changes in external K^＋, and subsequent regulation of K^＋-dependent root growth by modulating PINt degradation and auxin redistribution in the root.展开更多
A novel partial silicon-on-insulator （PSOI） high voltage device with a low-k （relative permittivity） dielectric buried layer （LK PSOI） and its breakdown mechanism are presented and investigated by MEDICI. At a l...A novel partial silicon-on-insulator （PSOI） high voltage device with a low-k （relative permittivity） dielectric buried layer （LK PSOI） and its breakdown mechanism are presented and investigated by MEDICI. At a low k value the electric field strength in the dielectric buried layer （EI） is enhanced and a Si window makes the substrate share the vertical drop, resulting in a high vertical breakdown voltage; in the lateral direction, a high electric field peak is introduced at the Si window, which modulates the electric field distribution in the SOI layer; consequently, a high breakdown voltage （BV） is obtained. The values of EI and BV of LK PSOI with ki = 2 on a 2μm thick SOI layer over 1μm thick buried layer are enhanced by 74% and 19%, respectively, compared with those of the conventional PSOI. Furthermore, the Si window also alleviates the self-heating effect.展开更多
This paper investigates the capacitance-voltage （C-V） characteristics of F doping SiCOH low dielectric constant films metal-insulator-semiconductor structure. The F doping SiCOH films are deposited by decamethylcycl...This paper investigates the capacitance-voltage （C-V） characteristics of F doping SiCOH low dielectric constant films metal-insulator-semiconductor structure. The F doping SiCOH films are deposited by decamethylcyclopentasilox-ane [DMCPS） and trifluromethane （CHF3） electron cyclotron resonance plasmas. With the CHF3/DMCPS flow rate ratio from 0 to 0.52, the positive excursion of C-V curves and the increase of fiat-band voltage VFB from -6.1 V to 32.2V are obtained. The excursion of C-V curves and the shift of VFB are related to the change of defects density and type at the Si/SiCOH interface due to the decrease of Si and O concentrations, and the increase of F concentration. At the CHF3/DMCPS flow rate ratio is 0.12, the compensation of F-bonding dangling bond to Si dangling bond leads to a small VFB of 2.0V.展开更多
The surface acoustic wave （SAW） technique is a precise and nondestructive method to detect the mechanical charac- teristics of the thin low dielectric constant （low-k） film by matching the theoretical dispersion c...The surface acoustic wave （SAW） technique is a precise and nondestructive method to detect the mechanical charac- teristics of the thin low dielectric constant （low-k） film by matching the theoretical dispersion curve with the experimental dispersion curve. In this paper, the influence of sample roughness on the precision of SAW mechanical detection is inves- tigated in detail. Random roughness values at the surface of low-k film and at the interface between this low-k film and the substrate are obtained by the Monte Carlo method. The dispersive characteristic of SAW on the layered structure with rough surface and rough interface is modeled by numerical simulation of finite element method. The Young＇s moduli of the Black DiamondTM samples with different roughness values are determined by SAWs in the experiment. The results show that the influence of sample roughness is very small when the root-mean-square （RMS） of roughness is smaller than 50 nm and correlation length is smaller than 20 μm. This study indicates that the SAW technique is reliable and precise in the nondestructive mechanical detection for low-k films.展开更多
This work investigated C2F6/O2/Ar plasma chemistry and its effect on the etching characteristics of SiCOH low-k dielectrics in 60 MHz/2 MHz dual-frequency capacitively coupled discharge. For the C2F6/Ar plasma, the in...This work investigated C2F6/O2/Ar plasma chemistry and its effect on the etching characteristics of SiCOH low-k dielectrics in 60 MHz/2 MHz dual-frequency capacitively coupled discharge. For the C2F6/Ar plasma, the increase in the low-frequency （LF） power led to an increased ion impact, prompting the dissociation of C2F6 with higher reaction energy. As a result, fluorocarbon radicals with a high F/C ratio decreased. The increase in the discharge pressure led to a decrease in the electron temperature, resulting in the decrease of C2F6 dissociation. For the C2F6/O2/Ar plasma, the increase in the LF power prompted the reaction between 02 and C2F6, resulting in the elimination of CF3 and CF2 radicals, and the production of an F-rich plasma environment. The F-rich plasma improved the etching characteristics of SiCOH low-k films, leading to a high etching rate and a smooth etched surface.展开更多
The characteristics of SiCOH low dielectric constant film treated by a trifluromethane （CHF3） electron cyclotron resonance （ECR） plasma was investigated. The flat-band voltage VFB and leakage current of the Cu/SiC...The characteristics of SiCOH low dielectric constant film treated by a trifluromethane （CHF3） electron cyclotron resonance （ECR） plasma was investigated. The flat-band voltage VFB and leakage current of the Cu/SiCOH/Si structure, and the hydrophobic property of the SiCOH film were obtained by the measurements of capacitance-voltage, current-voltage and water contact angle. The structures of the SiCOH film were also analyzed by Fourier transform infrared spectroscopy and atomic force microscopy. The CHF3 plasma treatment of the SiCOH film led to a reduction in both the fiat-band voltage VFB shift and leakage current of the Cu/SiCOH/Si structure, a decrease in surface roughness, and a deterioration of the hydrophobic property. The changes in the film＇s characteristics were related to the formation of Si-F bond, the increase in Si-OH bond, and the C：F deposition at the surface of the SiCOH film.展开更多
A low energy consumption clustering algorism based on LEACH is researched. Firstly, A method for obtaining the number of clusters k is given, then using the K-Means algorism to divide all the sensor nodes in WSN to th...A low energy consumption clustering algorism based on LEACH is researched. Firstly, A method for obtaining the number of clusters k is given, then using the K-Means algorism to divide all the sensor nodes in WSN to the k clusters, in the whole network life cycle the cluster will not changed, and when the energy of cluster head is lower than some threshold, it will be changed. The data transmission between cluster heads to sink node use mixed model, namely, the cluster near the sink node using the single hop and the one far from it using the multiple hops. The experiment shows our method has the longer life cycle and more received information. It is an effective clustering protocol.展开更多
文摘低压台区拓扑信息的准确记录是进行台区线损分析、三相不平衡治理等工作的基础。针对目前拓扑档案排查成本高且效率低的问题,提出一种基于自适应k近邻(adaptive k nearest neighbor,AKNN)异常检验和自适应密度峰值(adaptive density peaks clustering,ADPC)聚类的低压台区拓扑识别方法。该方法利用动态时间弯曲(dynamic time warping,DTW)距离度量低压台区用户间电压序列的相似性,通过AKNN异常检验算法检验并校正异常的用户与变压器之间的关系(简称“户变关系”),在得到正确户变关系的基础上,采用ADPC聚类算法对台区内用户进行相位识别;最后,通过实际台区算例分析验证了该方法不需要人为设置参数,能有效实现低压台区的拓扑识别,具有较高的适用性与准确性。
文摘Ethyl methane-sulfonate (EMS)-mutagenized Arabidopsis M-2 populations were screened in low-K+ medium using the root-bending assay. Forty-two putative low-k(+)-tolerant (lkt) mutants were selected from 150 000 tested M-2 seedlings, and two of these mutants maintained their low-K+-tolerant phenotype in their M-3 generations, respectively. Genetic analysis showed that either one of these two mutants has a monogenic recessive mutation in a nuclear gene, and that the two mutations in two independent mutants are allelic to each other.
基金supported by grants from the National Natural Science Foundation of China(31570243No.31622008No.31421062)
文摘The changes in external K^＋ concentration affect plant root growth. However, the molecular mechanism for perceiving a K^＋ signal to modulate root growth remains unknown. It is hypothesized that the K^＋ channel AKTI is involved in low K^＋ sensing in the Arabidopsis root and subsequent regulation of root growth. Along with the decline of external K^＋ concentration, the primary root growth of wild-type plants was gradually inhibited. However, the primary root of the akt1 mutant could still grow under low K^＋（LK） conditions. Application of NAA inhibited akt1 root growth, but promoted wild-type root growth under LK conditions. By using the ProDR5：GFP and ProPIN1：PIN1-GFP lines, we found that LK treatment reduced auxin accumulation in wild-type root tips by degrading PIN1 proteins, which did not occur in the akt1 mutant. The LK-induced PIN1 degradation may be due to the inhibition of vesicle trafficking of PIN1 proteins. In conclusion, our findings indicate that AKT1 is required for an Arabidopsis response to changes in external K^＋, and subsequent regulation of K^＋-dependent root growth by modulating PINt degradation and auxin redistribution in the root.
基金supported by the National Natural Science Foundation of China (Grant Nos. 60806025 and 60976060)the National Laboratory of Analog Integrated Circuit (Grant No. 9140C0903070904)the Youth Teacher Foundation of the University of Electronic Science and Technology of China (Grant No. jx0721)
文摘A novel partial silicon-on-insulator （PSOI） high voltage device with a low-k （relative permittivity） dielectric buried layer （LK PSOI） and its breakdown mechanism are presented and investigated by MEDICI. At a low k value the electric field strength in the dielectric buried layer （EI） is enhanced and a Si window makes the substrate share the vertical drop, resulting in a high vertical breakdown voltage; in the lateral direction, a high electric field peak is introduced at the Si window, which modulates the electric field distribution in the SOI layer; consequently, a high breakdown voltage （BV） is obtained. The values of EI and BV of LK PSOI with ki = 2 on a 2μm thick SOI layer over 1μm thick buried layer are enhanced by 74% and 19%, respectively, compared with those of the conventional PSOI. Furthermore, the Si window also alleviates the self-heating effect.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10575074)
文摘This paper investigates the capacitance-voltage （C-V） characteristics of F doping SiCOH low dielectric constant films metal-insulator-semiconductor structure. The F doping SiCOH films are deposited by decamethylcyclopentasilox-ane [DMCPS） and trifluromethane （CHF3） electron cyclotron resonance plasmas. With the CHF3/DMCPS flow rate ratio from 0 to 0.52, the positive excursion of C-V curves and the increase of fiat-band voltage VFB from -6.1 V to 32.2V are obtained. The excursion of C-V curves and the shift of VFB are related to the change of defects density and type at the Si/SiCOH interface due to the decrease of Si and O concentrations, and the increase of F concentration. At the CHF3/DMCPS flow rate ratio is 0.12, the compensation of F-bonding dangling bond to Si dangling bond leads to a small VFB of 2.0V.
基金Project supported by the National Natural Science Foundation of China(Grant No.60876072)the Tianjin Research Program of Application Foundation and Advanced Technology,China(Grant No.10JCZDJC15500)
文摘The surface acoustic wave （SAW） technique is a precise and nondestructive method to detect the mechanical charac- teristics of the thin low dielectric constant （low-k） film by matching the theoretical dispersion curve with the experimental dispersion curve. In this paper, the influence of sample roughness on the precision of SAW mechanical detection is inves- tigated in detail. Random roughness values at the surface of low-k film and at the interface between this low-k film and the substrate are obtained by the Monte Carlo method. The dispersive characteristic of SAW on the layered structure with rough surface and rough interface is modeled by numerical simulation of finite element method. The Young＇s moduli of the Black DiamondTM samples with different roughness values are determined by SAWs in the experiment. The results show that the influence of sample roughness is very small when the root-mean-square （RMS） of roughness is smaller than 50 nm and correlation length is smaller than 20 μm. This study indicates that the SAW technique is reliable and precise in the nondestructive mechanical detection for low-k films.
基金supported by National Natural Science Foundation of China(Nos.10975105,11075114)
文摘This work investigated C2F6/O2/Ar plasma chemistry and its effect on the etching characteristics of SiCOH low-k dielectrics in 60 MHz/2 MHz dual-frequency capacitively coupled discharge. For the C2F6/Ar plasma, the increase in the low-frequency （LF） power led to an increased ion impact, prompting the dissociation of C2F6 with higher reaction energy. As a result, fluorocarbon radicals with a high F/C ratio decreased. The increase in the discharge pressure led to a decrease in the electron temperature, resulting in the decrease of C2F6 dissociation. For the C2F6/O2/Ar plasma, the increase in the LF power prompted the reaction between 02 and C2F6, resulting in the elimination of CF3 and CF2 radicals, and the production of an F-rich plasma environment. The F-rich plasma improved the etching characteristics of SiCOH low-k films, leading to a high etching rate and a smooth etched surface.
基金supported by National Natural Science Foundation of China(Nos.10575074,10635010)
文摘The characteristics of SiCOH low dielectric constant film treated by a trifluromethane （CHF3） electron cyclotron resonance （ECR） plasma was investigated. The flat-band voltage VFB and leakage current of the Cu/SiCOH/Si structure, and the hydrophobic property of the SiCOH film were obtained by the measurements of capacitance-voltage, current-voltage and water contact angle. The structures of the SiCOH film were also analyzed by Fourier transform infrared spectroscopy and atomic force microscopy. The CHF3 plasma treatment of the SiCOH film led to a reduction in both the fiat-band voltage VFB shift and leakage current of the Cu/SiCOH/Si structure, a decrease in surface roughness, and a deterioration of the hydrophobic property. The changes in the film＇s characteristics were related to the formation of Si-F bond, the increase in Si-OH bond, and the C：F deposition at the surface of the SiCOH film.
文摘A low energy consumption clustering algorism based on LEACH is researched. Firstly, A method for obtaining the number of clusters k is given, then using the K-Means algorism to divide all the sensor nodes in WSN to the k clusters, in the whole network life cycle the cluster will not changed, and when the energy of cluster head is lower than some threshold, it will be changed. The data transmission between cluster heads to sink node use mixed model, namely, the cluster near the sink node using the single hop and the one far from it using the multiple hops. The experiment shows our method has the longer life cycle and more received information. It is an effective clustering protocol.
