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1.
Effective vibration recognition can improve the performance of vibration control and structural damage detection and is in high demand for signal processing and advanced classification.Signal-processing methods can extract the potent time-frequency-domain characteristics of signals;however,the performance of conventional characteristics-based classification needs to be improved.Widely used deep learning algorithms(e.g.,convolutional neural networks(CNNs))can conduct classification by extracting high-dimensional data features,with outstanding performance.Hence,combining the advantages of signal processing and deep-learning algorithms can significantly enhance vibration recognition performance.A novel vibration recognition method based on signal processing and deep neural networks is proposed herein.First,environmental vibration signals are collected;then,signal processing is conducted to obtain the coefficient matrices of the time-frequency-domain characteristics using three typical algorithms:the wavelet transform,Hilbert-Huang transform,and Mel frequency cepstral coefficient extraction method.Subsequently,CNNs,long short-term memory(LSTM)networks,and combined deep CNN-LSTM networks are trained for vibration recognition,according to the time-frequencydomain characteristics.Finally,the performance of the trained deep neural networks is evaluated and validated.The results confirm the effectiveness of the proposed vibration recognition method combining signal preprocessing and deep learning.  相似文献   

2.
Structural design simultaneously governed by earthquakes and environmental vibrations has received a lot of attention in recent years.Base-isolated composite structures are typically used in the above-mentioned structural design.The corresponding analysis involves validating structural safety under earthquakes and human comfort under environmental vibrations through a time-history analysis.Thus,a reasonable damping model is essential.In this work,the representatives of viscous damping model and rate-independent damping model,namely the Rayleigh damping model and uniform damping model,were adopted to investigate the influence of damping models on the time-history analysis of such structural designs.The energy dissipation characteristics of the above-mentioned damping models were illustrated via a dynamic test of recycled aggregate concrete specimens.A case study was performed on a base-isolated steelconcrete composite structure.The dynamic responses under the excitation of earthquakes and environmental vibrations were compared using different damping models.The uniform damping model was found to be more flexible than the Rayleigh damping model in dealing with excitations with different frequency components.The uniform damping model is both theoretically advantageous and easy to use,demonstrating its potential in dynamic analysis of structures designed simultaneously governed by earthquakes and environmental vibrations.  相似文献   

3.
回顾茅台酒的发展历史,作为一个具有悠久历史的品牌,作为民族酒业的杰出代表,国酒茅台几十年的辉煌业绩让每一个国人为她而骄傲。但它的巨大品牌优势同时也吸引了众多制假、售假者的目光。这些不法之徒大肆制售假茅台,严重侵害了企业和消费者的合法权益。对此,茅台酒厂投入了大量人力、物力、财力,在打假、防伪方面取得了很大的成效。据茅台打假办提供的信息表明,他们每年花在防伪打假上的各种费用达上亿元。总结茅台打假防伪的经验无疑对保护知名品牌是有益的。  相似文献   

4.
《标准生活》2015,(5):56-57
<正>婴幼儿皮肤的厚度仅为成人的十分之一,看似极微小的伤害都有可能对婴幼儿产生严重的影响。有统计显示,八成婴儿的肌肤问题都与衣物的处理不当有关,尤其是0-3岁的婴幼儿,他们的皮肤尚未发育完善,抵抗力差、容易过敏和吸收外物。同时,家长们的安全意识也比较薄弱,长期使用不正确的方式去除衣物上的甲醛、细菌和化学添加与残留物。目前为止,我国还没有专门针对婴儿洗衣液的国家或行业标准。婴幼儿衣物洗涤用品主要参照QB1224-2012《衣料用液体洗涤  相似文献   

5.
专访叶智荣     
《包装与设计》2015,(4):44-51
叶智荣,国际知名产品设计师. 叶智荣曾受聘于美国加州青蛙设计及飞利浦荷兰燕豪芬设计总部.1990年创立叶智荣设计有限公司.廿多年来经他设计之大小不同种类之产品1000多件,国际设计及发明专利数十项,国际客户:李宁、盛诺集团、生命动力、晨光文具、朗欣特、胜亚灯具、飞利浦、One for All、美国舒尔、沙宣、爷耆、Emerson、RCA、德国根德、任天堂、日立、山水、雅佳、韩国东洋、现代、大宇、中华煤气、金山电子.其中多项产品设计销量过百万件.  相似文献   

6.
公共交通优先发展,不仅体现落实科学发展观的客观要求,也是建设资源节约型、环境友好型社会的重要举措。但孝感市公共交发展存在公交车辆总量不足、公交车辆道路运行难、公交车辆运营调度技术手段和票务方式落后等问题。于是,研究深入调查分析产生这些问题的原因并提出相应的对策与建议,这有其一定的现实指导意义。  相似文献   

7.
Developing an electrically conductive and corrosion-resistant coating is essential for metal bipolar plates of polymer electrolyte membrane fuel cells(PEMFCs). Although enhanced corrosion resistance was seen for Cr coated stainless steel(Cr/SS) bipolar plates, they experience a quick decrease of through-plane electrical conductivity due to the formation of a porous and low-conductive corrosion product layer at the plate surface, thus leading to an increase in interfacial contact resistance(ICR). To tackle this issue, the multilayer Cr coatings were deposited using the magnetron sputtering with a remote inductively coupled oxygen plasma(O-ICP) in the present study. After the O-ICP treatment, a Cr oxide layer(Cr O*) is formed on the specimen surface. The Cr O*/Cr/SS has a remarkably lower stable corrosion rate(iss) than that of the native Cr oxides(Cr On/Cr/SS). Compared with Cr On/Cr/SS, the excellent performance of Cr O*/Cr/SS is attributed to a denser and thicker surface layer of Cr O* with Cr being oxidized to its highest valence state,Cr(VI). More importantly, the through-plane electrical conductivity of the specimens treated by the optimized O-ICP decreases much slowly than Cr On/Cr/SS and thus, the increament of ICR of Cr O*/Cr/SS after the potentiostatic polarization test is considerably smaller than that of Cr On/Cr/SS, which is benefited from the reduced issthat mitigates the deposition of corrosion products and hinders further oxidation of Cr coating. Therefore, Cr O*/Cr/SS proves to be a well balanced trade-off between corrosion resistance and through-plane electrical conductivity. The results of this study demonstrate that O-ICP treatment on a conductive metal coating is an effective strategy to improve the corrosion resistance and suppress the increase of ICR over the long-term polarization. The technique reported herein exhibits its promising potential application in preparing corrosion resistant and electrically conductive coatings on metal bipolar plates to be used in PEMFCs.  相似文献   

8.
张雷 《标准生活》2015,(5):24-29
<正>2013年,上海质监局对该市22批次学生服产品进行抽检,发现6个批次产品存在质量问题,而供应多家学校的某服装公司生产的校服产品存在致癌威胁;2014年,美国第一夫人米歇尔访华引发中国校服"丑到爆"的讨论;2015年,广东东莞又曝出2180元的"天价校服"事件。从质量到款式,再到价格,关于国内校服的争论可谓年复一年,从未停止。中国校服如此备受质疑,却又总是难以加快前进的脚步,使其背后标准的缺失问题也逐渐暴露。中小学生校服问  相似文献   

9.
《标准生活》2015,(4):62-65
<正>涂料成随地小便"克星"一些男士有找个角落随地小便的不良习惯。但如果你正好在德国汉堡,而且不想尿自己一身的话,那么就请不要在这座城市的红灯区里随地小便。汉堡市的圣保利红灯区是这座城市的顶级娱乐区,这里流行的夜店俱乐部和合法色情服务每年吸引超过2000万的游客前来。然而纷至沓来的游客也让当地的居民和商户感到气愤,因为很多男人会习惯性的在墙角边(或是任何他们能够找到的垂直立面旁)小解,这让将近1英里长的圣保  相似文献   

10.
《标准生活》2015,(5):50-55
<正>在我们选购服装时,除了亲自看、摸、闻外,标签是最能体现服装资料的重要标识。别看只是一张小小的纸片,但它涵盖了一件衣服的所有数据,包括面料、规格、大小等等细节信息,这些都是消费者选购时必须参考的重要依据。为了不影响服装的销售以及避免穿着后身体感到不适,通常标签都会将信息以数字或英文的形式,复印在一张很小的卡片或衣服领口的布头上。那么你真的了解服装标签上的这些符号吗?它们究竟代  相似文献   

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