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991.
近年来,电子信息技术不断发展,设备与设备之间的信息传递方式也在不断地改进,目前比较流行的接口类型包括RS232、RS422、IISB2.0等多种类型,操控设备作为一种人机接口设备。应用范同广泛,可与多种接口对接。为了适应这种现状的需要,提高设备通用性。该文提出一种多接口冗余设计技术,适应不同场合的需要,操控设备可与多种接口设备对接。经过测试验证并在某型号系统上试用,证明其操控灵活接口应用方便,符合设计的要求。 相似文献
992.
对新疆啤酒花中最重要的 3个品种 (青岛大花、麒麟丰绿、余乐比特 )及一个新培育的品种阜北 -1进行了化学成分及储存性能研究 ,同时与国外引种的 3个优良品种 (马可波罗、努革特及札一 )进行比较。结果表明 :新疆的青岛大花、麒麟丰绿是 α-酸含量中低的苦型花 ,合草酮都占总α-酸的 4 0 %以上 ,酿造品质一般 ;余乐比特和新品种阜北 -1是香型花 ,合草酮分别占总 α-酸的 2 2 .70 %和 3 0 .73 % ,酿造品质较佳 ,酒花油有香型花特点 ;引种的马可波罗和努革特是高α-酸的苦型花 ,札一是香型花 ,它们都保持了原花的优良性能 ;上述 7种啤酒花储存 1 0 0 d后 ,α-酸损失在 8%~ 1 4% ,故不宜久放 ,应尽快加工。 相似文献
993.
994.
995.
蓖麻油碱炼脱酸的理论与实践 总被引:2,自引:0,他引:2
采用理论与实践相结合的笔法,论述了理论指导下的蓖麻油碱炼脱酸过程,又通过蓖麻油碱炼脱酸的生产实践验证,丰富着经典理论,提出蓖麻油碱炼脱酸的理论,从而,将科技转化为生产力。 相似文献
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997.
Adaptive bit-loading is a key technology in high speed power line communications with the Orthogonal Frequency Division Multiplexing (OFDM) modulation technology. According to the real situation of the transmitting power spectrum limited in high speed power line communications, this paper explored the adaptive bit loading algorithm to maximize transmission bit number when transmitting power spectral density and bit error rate are not exceed upper limit. With the characteristics of the power line channel, first of all, it obtains the optimal bit loading algorithm, and then provides the improved algorithm to reduce the computational complexity. Based on the analysis and simulation, it offers a non-iterative bit allocation algorithm, and finally the simulation shows that this new algorithm can greatly reduce the computational complexity, and the actual bit allocation results close to optimal. 相似文献
998.
Zhongyuan Zhao Mugen Peng Yingna Ma Yong Li Yang Changqing Yong Wu 《Journal of Signal Processing Systems》2016,82(2):207-215
This paper presents a generalized i-vector representation framework with phonetic tokenization and tandem features for text independent as well as text dependent speaker verification. In the conventional i-vector framework, the tokens for calculating the zero-order and first-order Baum-Welch statistics are Gaussian Mixture Model (GMM) components trained from acoustic level MFCC features. Yet besides MFCC, we believe that phonetic information makes another direction that can benefit the system performance. Our contribution in this paper lies in integrating phonetic information into the i-vector representation by several extensions, forming a more generalized i-vector framework. First, the tokens for calculating the zero-order statistics is extended from the MFCC trained GMM components to phonetic phonemes, trigrams and tandem feature trained GMM components, using phoneme posterior probabilities. Second, given the zero-order statistics (posterior probabilities on tokens), the feature used to calculate the first-order statistics is also extended from MFCC to tandem feature, and is not necessarily the same feature employed by the tokenizer. Third, the zero-order and first-order statistics vectors are then concatenated and represented by the simplified supervised i-vector approach followed by the standard Probabilistic Linear Discriminant Analysis (PLDA) back-end. We study different token and feature combinations, and we show that the feature level fusion of acoustic level MFCC features and phonetic level tandem features with GMM based i-vector representation achieves the best performance for text independent speaker verification. Furthermore, we demonstrate that the phonetic level phoneme constraints introduced by the tandem features help the text dependent speaker verification system to reject wrong password trials and improve the performance dramatically. Experimental results are reported on the NIST SRE 2010 common condition 5 female part task and the RSR 2015 part 1 female part task for text independent and text dependent speaker verification, respectively. For the text independent speaker verification task, the proposed generalized i-vector representation outperforms the i-vector baseline by relatively 53 % in terms of equal error rate (EER) and norm minDCF values. For the text dependent speaker verification task, our proposed approach also reduced the EER significantly from 23 % to 90 % relatively for different types of trials. 相似文献
999.
单模光纤SRS的实验用的是Nd:YAG调Q倍频激光作泵浦源,用快速雪崩二极管探测光脉冲信息,用存储示波器记录波形,光路如图1。图中1是JGM-1型色心调QNd:YAG激光器,倍频后(0.53μm)脉宽为20ns,输出能量为125μJ~100mJ。2是滤去1.06μm剩余光的滤光片,3是分束片,4是LPE-IA激光功率/能量计,以监视输入能量,5、7是耦合透镜,6是光纤,8是单色仪,9是Ge- 相似文献
1000.
This paper describes and analyses the impact of the Ti layer, which is embedded between the insulator and top electrode, on the programming characteristic of the Al-HfO2-Al antifuse. The programming voltage of the antifuse with 120 Å HfO2 is properly reduced from 5.5 to 4.6 V with an embedded Ti layer. Low on-state resistance (~19 Ω) and low programming voltage (4.6 V) is demonstrated in the embedded Ti antifuse with 120 Å HfO2 while keeping sufficient off-state reliability. The antifuse embedded with a Ti layer between the insulator and top electrode has been developed and has potential in field programmable devices. 相似文献