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31.
32.
物联网(internet of things,IOT)拥有无处不在的识别、传感和通信能力,体域网(body area network,BAN)属于物联网中和人体相关的领域,其应用广泛,可以在日常生活中对人们进行监测及提供帮助.行走是许多日常活动的基本环节,因而步态分析能为体域网应用提供重要的生理行为信息.现有的步态分析已取得一定的研究成果,但仍存在一些问题,例如大多数步态特征提取是对加速度信号进行6重以上的变换,使得特征达到了45维以上,最后需要通过降维或优化来简化特征,较为复杂.本文设计一种灵活便捷的数据采集系统,并利用小波变换、傅里叶变换和四分位差提取出加速度信号中比较简单、低维度但能反应运动特征的步态参数,之后通过模式识别算法进行步态行为识别验证.实验结果表明该系统使用方便,特征提取方法简单实用,识别精确度为97%,EER(equal error rate)最小可到0.9%. 相似文献
33.
Tingting Yu 《Journal of Natural History》2015,49(9-10):509-526
Pseudelzalia longiseta gen. nov, sp. nov. and Paramonohystera sinica sp. nov. from subtidal sediment in the East China Sea are described. Pseudelzalia is characterized by 6 labial papillae and 10 cephalic setae, cylindrical buccal cavity, elongate (>2 anal body diameter) spicules, and conico-cylindrical tail devoid of terminal setae. It differs from Elzalia by the absence of terminal setae. Pseudelzalia longiseta sp. nov. is 647–853 μm long, has 7–8 μm long cervical setae, 11–14 μm long caudal setae, 25–41 μm long spicules about 2.1–2.7 anal diameter, and pointed tail-tip. Paramonohystera sinica possesses 12 cephalic setae, a character found in four congeners: Paramonohystera buetschlii (Bresslau and Schuurmans Stekhoven in Schuurmans Stekhoven, 1935, Paramonohystera pilosa Boucher, 1971, Paramonohystera concinna Lorenzen, 1977 and Paramonohystera halerba Fadeeva and Belogurov, 1987. It differs from P. buetschlii by shorter body (933–1023 μm versus 2000–2200 μm); from P. pilosa by the much shorter spicules (79–88 μm versus 167 μm) and narrower head (13–16 µm versus 32 µm); from P.concinna by smooth cephalic setae (versus segmented); and from P. halerba by the absence of two rows of setae on the ventral side of the tail (versus present). Based on the evaluation of nominal species, we recognize 14 valid species and provide an emended diagnosis and a tabular key for Paramonohystera.http://www.zoobank.org/urn:lsid:zoobank.org:pub:474B8F17-AED7-4078-8176-DFC499B78526 相似文献
34.
《Journal of Natural History》2012,46(23):2109-2123
Three new species of marine nematodes belonging to the genera Paranticoma (family Anticomidae) and Parodontophora (family Axonolaimidae) are described from the Bohai Sea and Yellow Sea. Paranticoma tricerviseta sp. nov. is similar to P. bandaenseMicoletzky and Kreis, in the spicules, but can be distinguished by the presence of a ventral projection on the spicules, three regularly arranged cervical setae in both the male and female, and two distinct ventral setae behind the anus. Parodontophora deltensis sp. nov. is close to P. paragranulifera (Timm, ) in the length of the amphids, with the ventral arm of the amphid extending past the base of the stoma, but can be separated by the ratio of dorsal arm length to ventral arm (0.36–0.55 versus 0.20–0.25) and the position of the excretory pore (at the middle level versus top level of the stoma), distinctive cervical setae arrangement and a longer renette cell. Parodontophora wuleidaowanensis sp. nov. is close to P. danker Belogurov and Kartavtseva, in the form of the amphids, but can be distinguished by the longer length of the ventral arm of the amphids and the distinctive arrangement of cervical setae. 相似文献
35.
《Journal of Natural History》2012,46(3-4):157-176
Collecting in southern Spain yielded five species of Parotoplana and one species of Parotoplanella (Proseriata: Otoplanidae). Four species of Paratoplana proved to be new to science. Parotoplana cucullata sp. n. is distinguished by the shape of the lateral spines in the copulatory organ and in the presence of a “glandular organ” around the distal portion of the female duct. Parotoplana fretigaditani sp. n. is similar to P. procerostyla Ax, 1956 in the general arrangement of spines, but their fine morphology is distinctive. Parotoplana varispinosa sp. n. differs from P. capitata Ax, 1956 in the shape and number of spines. Parotoplana mastigophora sp. n. has a unique morphology of the stylet, and the spines of the girdle markedly differ in size and shape. The karyotype of P. cucullata sp. n. (n = 6) is described. In addition, Parotoplana primitiva and Parotoplanella heterorhabditica, previously known from the Atlantic coast of France and north‐west Mediterranean, respectively, were found. The high proportion of new species demonstrates the present poor state of knowledge of interstial meiofauna. 相似文献
36.
《Journal of Natural History》2012,46(37-38):2391-2423
The present study raises the number of Ampelisca species recorded from the Brazilian coast from 18 to 21. The amphipod fauna of the Brazilian northeast coast is hardly known compared to that of the southeast coast. In this study, we describe three new species from the northeast coast: Ampelisca pseudobicarinata sp. nov., Ampelisca rocasensis sp. nov. and Ampelisca cristianae sp. nov, recorded previously as Ampelisca aff. lobata (Serejo et al. 2000). We also report a new record of Ampelisca burkei Barnard and Thomas, 1989. From the southeast coast a new species Ampelisca angraensis sp. nov. is described. An obscure species, Ampelisca soleata, which is very similar to Ampelisca brevisimulata, is herein redescribed and a neotype is designated. An updated key with all species of Ampelisca recorded from the Brazilian coast and comments on geographic distribution are given. 相似文献
37.
38.
《Journal of Natural History》2012,46(2):407-414
Lernanthropus antofagastensis sp. nov., parasitic on Anisotremus scapularis, and inshore fish of Antofagasta, Chile, is described and illustrated. It resembles five other species of Lernanthropus in its dorsal plate and third leg, but can be distinguished from them by a combination of characters. L. trachuri Brian, 1903, is recorded, its male described and illustrated from specimens collected from Seriolella violacea and Trachurus murphy, taken in the same locality. 相似文献
39.
随着海岸侵蚀和海岸线后退,人类的生存和生活环境遭到威胁。目前常用的海岸防护措施极易遭到自然灾害破坏,不经济、不环保且耗费大量维修费用,而微生物诱导碳酸钙沉淀(MICP)技术可以显著改善土体强度、刚度、渗透性及抗液化性能,并且相比于传统土体改良工艺,其绿色环保、环境友好型特点更加符合可持续发展理念,在砂土体加固领域有着非常广阔的工程应用前景。系统地总结了国内外关于微生物法加固砂土堤岸的室内及现场试验研究的最新成果,并对微生物固化土体的力学特性进行了研究论述。 相似文献
40.
采用原子吸收分光光度计,分别测试经机械抛光和高温氧化后的NiTi合金样品在人体生理模拟液中镍离子的释放速度,结果表明NiTi合金表面氧化膜的形成可以有效地减少镍离子的溶出. 相似文献