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1.
A novel method for assessing the accuracy of inertial/magnetic sensors is presented. The method, referred to as the “residual matrix” method, is advantageous because it decouples the sensor's error with respect to Earth's gravity vector (attitude residual error: pitch and roll) from the sensor's error with respect to magnetic north (heading residual error), while remaining insensitive to singularity problems when the second Euler rotation is close to ±90°. As a demonstration, the accuracy of an inertial/magnetic sensor mounted to a participant's forearm was evaluated during a reaching task in a laboratory. Sensor orientation was measured internally (by the inertial/magnetic sensor) and externally using an optoelectronic measurement system with a marker cluster rigidly attached to the sensor's enclosure. Roll, pitch and heading residuals were calculated using the proposed novel method, as well as using a common orientation assessment method where the residuals are defined as the difference between the Euler angles measured by the inertial sensor and those measured by the optoelectronic system. Using the proposed residual matrix method, the roll and pitch residuals remained less than 1° and, as expected, no statistically significant difference between these two measures of attitude accuracy was found; the heading residuals were significantly larger than the attitude residuals but remained below 2°. Using the direct Euler angle comparison method, the residuals were in general larger due to singularity issues, and the expected significant difference between inertial/magnetic sensor attitude and heading accuracy was not present.  相似文献   
2.
《L'Anthropologie》2021,125(5):102970
In the Japanese Archipelago, Upper Palaeolithic Accessories, Pigment and Portable Art are discovered, but very few. We introduce the Palaeolithic Art in Japan including new discoveries. The majority of accessories is discovered in Hokkaido, for example the sites of Yunosato 4, Pirika 1, Kashiwadai1 and Obarubetsu 2, but very few in Honshu, the largest island of Japan: Togeyamabokujo 1 in Iwate and Fujiishi in Shizuoka. A lot of pigments are discovered in Hokkaido like Kawanishi C, Kashiwadai 1, Marukoyama and Kiusu 5, without those of Deguchi-Kanezuka in Chiba in Honshu. Kashiwadai 1 in Hokkaido and Kamihikikiri in Chiba are the sites with portable art. In Ehime in Shikoku, one of four large islands of Japan, engraved pebbles called “Kamikuroiwa Venus”, of the Incipient Jomon followed after the Upper Palaeolithic period, before about 14,500 years, are researched again recently. The Palaeolithic art in Japan has a strong relation with Northeast Asia's art, because the lithic materials of Palaeolithic accessories in Hokkaido came from the Continent, and the engraved pebbles have some characters common with Siberian figurines, but also there are accessories and pigment of which the stones are native of the region from the beginning of the Upper Palaeolithic period.  相似文献   
3.
目的:检测儿童的平衡能力和下肢力量,研究评估儿童运动能力的相关指标。方法:设计了一套便携式运动能力检测系统,检测儿童的平衡能力和下肢力量。本系统由运动能力检测设备和上位机数据分析存储展示部分组成。结果:研制的便携式运动能力检测系统具有可穿戴、功耗低等优点,能够准确地记录儿童的运动数据。结论:便携式运动能力检测系统能够检测使用者在运动过程中的平衡数据和下肢力量数据,及时发现运动能力的缺陷,为儿童的日常生活和锻炼提供参考。  相似文献   
4.
《L'Anthropologie》2019,123(1):1-18
This paper reports the discovery of a new example of portable art in North-eastern Iberia dating to the Late Upper Palaeolithic (12.250 ± 60 BP). The piece is analysed in relation to the European Palaeolithic art assemblage to determine its significance and how it contributes to our understandings of Palaeolithic artistic practices. Both the motifs depicted (birds and humans) and the patterns of composition (a narrative scene) are unusual in Palaeolithic assemblages. In addition, this new find contributes to filling a geographic gap in the artistic record as evidence of Palaeolithic art is rare in Catalonia. The anatomical features of one of the birds suggest that it is a crane, a species that has been depicted in a limited number of sites, as summarized in this paper. Moreover, there are only three known example of birds and humans interacting in a narrative scene in Palaeolithic art. Exhibiting innovations in media, subject matter and compositional norms, this new find has the potential to change the classic definition of European Upper Palaeolithic art and integrate the region in the artistic trends circulating along Mediterranean Iberia during the Upper Magdalenian.  相似文献   
5.
《国际植物命名法规》的修订由每六年一次的国际植物学大会(IBC)命名分会来决定。第18届国际植物学大会在澳大利亚墨尔本举行;命名分会于2011年7月18日至22日召开,其决议获得7月30日的全体会议通过。“墨尔本法规”有几个重要的变化,将影响新名称的发表。这些变化中的两个将在“墨尔本法规”出版前的几个月,即于2012年1月1日起生效。通过以移动文档格式(Portable Document Format;pdf)在线发表的具有国际标准连续出版物号(ISSN)或国际标准图书编号(ISBN)的电子出版物,将构成有效发表。新分类群名称的合格发表所必须的拉丁文描述或特征集要将更改为拉丁文或英文描述或特征集要。此外,自2013年1月1日起,被处理为真菌的生物的新名称必须在原始资料(某一名称合格发表时与之有关的所有资料)中引证一个由一家公认的存储库(例如MycoBank)签发的标识码,才构成合格发表。本文提供了有关电子出版物的新规则的草案文本,并概述了相应的最佳做法。  相似文献   
6.
目的:建立基于核酸序列分析的快速、准确、低成本的甲型H1N1流感病毒检测方法。方法:通过优化焦测序反应体系中ATP硫酸化酶和荧光素酶的浓度,建立高灵敏的焦测序反应体系;将该体系应用于低成本、小型化的便携式生物发光分析仪,焦测序分析流感病毒M、NP、HA基因片段的核酸序列。结果:优化后的焦测序反应体系可检测低至10 fmol的DNA样本,检测灵敏度较传统焦测序提高了10倍以上。对两例样本进行检测,根据所测得的M、NP、HA基因特异性片段序列,可以确认其均为甲型H1N1感染;另外,对M2蛋白阻断剂耐药性标志位点(S31N突变)的测定结果显示该病毒存在S31N突变,为M2蛋白阻断剂耐药型。结论:高灵敏焦测序体系结合便携式生物发光分析仪成功实现了对甲型H1N1流感病毒快速、准确的低成本检测。  相似文献   
7.
目的:研制一种新型便携式数字化温控烫伤仪,通过自制数字化烫伤仪对大鼠进行烫伤实验,建立标准化大鼠皮肤烫伤模型,从而验证数字化烫伤仪的有效及实用性。方法:选取18只SD大鼠分为对照组(3只,不烫伤);实验组(15只),再将实验组大鼠随机分配为A组(6只)、B组(6只)、C组(3只),选取大鼠背部作为烫伤实验部位:1、时间设定为20 s和30 s,烫伤仪温度分别设定为70℃、80℃、90℃、100℃、120℃,对A组和B组大鼠进行烫伤处理。2、温度设定为100℃,烫伤仪加热时间分别设定为10 s、15 s、25 s,对C组大鼠进行烫伤处理。烫伤后48 h切取实验组和对照组大鼠背部皮肤,进行大体及显微镜下组织病理学观察。结果:70℃20s烫伤点为I°烫伤;70℃30 s、80℃20 s、100℃10 s烫伤点为浅Ⅱ°烫伤;80℃30 s和100℃15 s烫伤点为深Ⅱ°烫伤;90℃20 s、90℃30 s、100℃20 s烫伤点为Ⅲ°烫伤;100℃25 s、100℃30 s、120℃20 s、120℃30 s烫伤点为IV°烫伤。结论:新型便携式数字化温控烫伤仪,可以可靠的建立标准化大鼠皮肤烫伤模型。  相似文献   
8.
针对心电信号处理过程中的心电信号数字滤波、心电波形的动态显示、心电数据存储等问题,阐述了3个可用于心电信号实时处理的方法:一是运用滤波器频谱的周期性减少了滤波器系数个数,提高了运算速度,并根据卷积公式特点实现了数字滤波的实时性;二是运用基于内存虚拟屏幕技术实现心电波形动态显示,解决了屏幕闪烁和绘图不连续问题;三是采用嵌入式数据库SQLITE实现了心电数据存储。所有方法均考虑实时性要求,并已成功用于课题组开发的便携式心电监护仪,效果较为理想,具有很强的实用价值。  相似文献   
9.
《L'Anthropologie》2023,127(1):103094
All but one of the published radiocarbon dates from the 1991–1992 excavations of Strata 3 and 2 at le Trou Magrite are considered too recent because the dating was done with then-standard chemical pretreatment protocols. This study re-dates Stratum 2 using the same, then-pioneering, XAD-2 purification method on bone collagen as had been used for the 44,650 cal BP date from Stratum 3. The results are two averaged dates that are in stratigraphic order between themselves and in relation to the Stratum 3 date: 43,400 and 43,500 cal BP, according to the IntCal20 curve. These dates are very similar to recently published dates for the earliest Aurignacian in SW Germany and the latest Neanderthal remains in Belgium and they are associated with artifact assemblages that, without obvious evidence of mixture (other than that which was highly localized), include Upper Paleolithic stone tools and blades/bladelets together with numerous sidescrapers, denticulates and notches which are not exclusively Mousterian artifacts. Nineteenth-century excavations in the cave of le Trou Magrite yielded unambiguously diagnostic Aurignacian artifacts and works of portable art that could conceivably have been from a deposit equivalent in age to these strata on the contiguous terrace. It is clear that the first blade(let)-rich assemblages in the site were created on the cusp of the transition from the Middle-to-Upper Paleolithic transition and replacement of the Neanderthals in NW Europe.  相似文献   
10.
The application of a quinoprotein glucose dehydrogenase modified thick-film sensor as label detector in a capillary immunoassay (CIA) for xenoestrogens is presented. The detection of the alkylphenols and their ethoxylates is based on the competition between the analyte and tracer molecules for the binding sites of anti-alkylphenol ethoxylate antibodies. This assay is performed off-line in small disposable PVC capillaries coated with immobilized antibodies. This format allows the combination of the assay with a small portable device potentially useful for on-site environmental monitoring. Beside high amplification the utilization of beta-galactosidase as enzyme label allows the direct combination with a GDH biosensor at optimal pH conditions. The bioelectrocatalytic properties of this biosensor offer an additional amplification and thus allow a very sensitive quantification of 4-aminophenol, generated by the beta-galactosidase. Detection limits of the analytes in the microg/l range were obtained, while other phenolics and surfactants showed no or very little cross reactivity.  相似文献   
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