虚拟现实运动病的生理评价方法研究

针对运动病生理评价方法实验研究较少的现状,通过单因素重复测量的实验设计方法探究得到一种新的虚拟现实运动病的生理评价方法。研究结果表明,不同的实验情境会显著影响心率指标(P0.05)与皮电指标(P0.05),非虚拟现实因素会显著影响皮电指标(P0.05);心率适宜作为评价虚拟现实运动病的生理指标而皮电与呼吸频率不适宜,且患者的心率在其产生症状后会显著增加;心率、呼吸频率、皮电均无法评价虚拟现实运动病的病状程度。     

皮肤电信号在产品外观偏好评价中的应用研究

目的研究皮肤电信号(GSR)与用户对产品外观的情感体验存在的对应关系,验证皮电信号用于检测产品外观的偏好体验的可能性。方法以座椅的不同外观方案为诱发材料,采集被试观看不同外观座椅的皮肤电信号,对信号进行预处理及特征提取,作出相应的数理统计,并与被试的主观问卷进行比较分析。结果观看者观看过程中皮电整体呈现缓慢下降,但对偏好产品会出现皮电实时升高的情况;观看不同座椅时观看者的皮电信号呈现显著性差异;在70%(73.3%)以上的情况下,皮电显著升高的座椅方案与被试主观问卷填写的偏好方案有对应关系。结论在无巨大新异方案的情况下,皮电信号能较好地实时反映观看者的偏好情绪,其主要为一种唤醒程度,对产品外观方案评价具有较好的应用价值。     

儿童乘坐安全座椅压力—舒适性探究

目的 探究儿童在乘坐安全座椅时背部与臀部接触区域的舒适性差异,得出背部和臀部的压力舒适区域,为今后的设计提供一定理论基础.方法 招募8名4～8岁的健康儿童作为被试,让被试先后坐在三款儿童安全座椅上,提取压力数据并做舒适性主观测试;计算标准差检验座椅的稳定性,进行配对样本t检验比较座椅间的差异性;绘制压力—舒适性图像验证舒适与不适的区域.结果 在"瞬时"压力测试中C座椅界面压力分配方案最优,与主观测试结果一致(C>B>A).在"10 min"的压力测试中,B座椅的峰值压力更稳定,A、C座椅无显著差异,与主观测试结果不一致,推测儿童对安全座椅的舒适性判断取决于入座时的第一印象.结论 实验结果表明4～8岁儿童在乘坐不同安全座椅时,材质偏硬、坐面造型平坦的安全座椅对人体的压迫性更强;材质偏软、包裹性强的安全座椅更贴合人机形态,舒适性更高.     

基于ECG和HRV特征提取的情绪状态分析

心电(ECG)和心率变异性(HRV)是心脏活动的直接响应,与自主神经系统有着密切关系,不同情绪状态有特定的自主神经反应模式,因而ECG和HRV可以反映人体情绪变化.本文利用Augsburg大学建立的情感生理数据库,选取音乐情感诱发下的心电信号,对其进行滤波处理去除噪声和干扰;采用小波变换提取心电信号小波系数的模极值和过零点,得到心电R波信号,计算其一阶差分,获得4种情绪状态下的心率变异性特征信号;提取情绪诱发的心电和心率变异性信号的时域、频域和小波熵时频特征,并对特征进行差异统计检验和情绪状态分析.仿真结果表明,HRV特征相比ECG特征可以更有效地反映人体的情绪状态,小波熵特征和HRV频谱总功率特征对于不同情绪状态的差异性更显著,该研究可为机器情绪识别提供借鉴.     

视觉刺激诱发情绪的表达抑制研究

目的研究视觉刺激诱发情绪的表达抑制对表达行为、主观体验、生理反应等系统的影响,以及表达抑制与记忆的关系。方法以32名女性为被试,采用生理和心理实验法测量被试观看电影片段的表达行为、主观体验和生理反应变化及表达抑制对记忆任务绩效的影响。结果与控制组相比,抑制组被试表情行为被抑制但仍能体验所诱发的情绪,心率变异性和皮电水平显著增加,听觉信息记忆绩效下降。结论表达抑制不对主观体验起作用但会引起交感神经激活增加,并伴有一定程度的认知代价。     

太空锻炼区人机界面色彩环境舒适度设计研究

目的 研究载人航天器锻炼区在不同色彩环境下对运动锻炼的色彩环境舒适度、运动欲望及心率上升率的影响。方法 36名受试者分为头低位组(实验组)和立位组(对照组),实验要求被试者进行主观问卷评价,同时采集实验中的客观数据。对主观评价结果进行方差分析,并对心率信号进行心率上升率换算,分析不同色彩下主观评价和心率数据的差异。最后以航天器锻炼区的色彩搭配为例进行设计验证。结果 主观评价显示,不同颜色对心理状态都有显著性差异;在色彩环境舒适度上,通过研究冷暖色调对运动色彩环境舒适度均值的影响后发现,无色彩环境相对于其他颜色表现出显著差异性;在运动欲望上,通过分析色彩的冷暖色调对运动欲望均值的影响发现,暖色环境相对于冷色表现出显著差异性。客观数据显示,不同色彩下心率波动均在正常范围内,而不同色彩环境下心率上升率差异不大,无统计学意义。在不同状态下心率上升率有显著差异。结论 在狭小、密闭的锻炼空间中,暖色环境相比冷色环境和无色彩环境更容易影响人的运动欲望,其中黄色环境表现较为明显,而相比有色彩环境下,在无色彩环境下的运动则更为舒适。最后依据实验结论开展设计实践。     

座椅材料的热舒适及其评价

本文分析了座椅的热舒适性对人体的影响,阐述了座椅材料与热舒适相关的几项物理性能及测试方法,最后提出了座椅热舒适性的主客观评价方法。在客观评价方法中,除测试座椅材料的热物理指标外,还可以采用探头式温湿度计测量人一椅界面问温湿度,同时进行主观评价,从而将主客观评价结果很好的联系起来。     

基于眼动和脑电技术的机器人情绪行为对用户交互情感的影响研究

目的探索人-机器人交互过程中用户情感的评价方法,揭示机器人情绪行为对用户交互情感的影响。方法设计音乐交互过程(正性音乐、负性音乐)和机器人情绪行为(正性情绪行为、中性情绪行为、负性情绪行为),借助主观评价、眼动追踪和脑电技术,采集19名被试在不同音乐交互过程中的主观评价指标、眼动指标和脑电指标。结果正性音乐交互过程中,机器人正性情绪行为引起的效价、唤醒度、瞳孔直径、额中线theta波相对功率、额区alpha波不对称指数显著大于中性情绪行为;而负性音乐交互过程中,机器人负性情绪行为引起的唤醒度和瞳孔直径显著大于中性情绪行为,效价和额区alpha波不对称指数显著小于中性情绪行为。结论各评价指标具有一致的结果,各指标相互结合能够有效地评价机器人音乐交互过程中用户的情感状态。评价结果表明机器人正性情绪行为(负性情绪行为)对音乐交互过程中用户正性情感(负性情感)具有增强作用,可用于进一步加强机器人音乐交互过程中用户的情感。     

基于眼动实验的服装纹样布局方案意象评价模型

目的 针对目前服装纹样布局方案评价中主观性较强、方案评选角度单一、结果可靠性不佳的问题,将客观生理数据测量和主观意象评价相结合,探索用户非主观意识下生理认知数据与心理主观评价间的关系。方法 采用形状文法设计实验样本,建立意象词汇空间,通过问卷调查与眼动实验获取主观意象打分和眼动生理指标数据;数据进行相关性分析,采用单因变量偏最小二乘回归对不同意象词对下主观意象评价值与眼动生理指标之间的相关关系进行拟合,并对拟合后的评价模型进行分析与验证。结果 得出在不同的意象词汇的刺激下,主观评价与眼动生理指标之间存在较高相关性。结论 意象评价模型可以有效准确地反映出用户对服装纹样布局方案的主观评价,为服装纹样布局方案评选提供一种更加客观的评价方式。     

基于熵权—VIKOR法的椅类家具舒适性设计评价

目的 为了解决椅类家具舒适性设计评价过程中主观赋值的模糊性、不确定性及主观与客观结合时的权重比例的分配不合理所造成的评价结果的较大误差,为椅类家具设计提供更为客观且简单易用的评价方法.方法 运用用户体验理论和FFORDANCE理论构建较为科学和全面的椅类家具舒适性设计评价指标体系;利用熵权体系排除决策者在赋权中的主观因素并利用VIKOR法最大化群体效用使评估者接受其折衷解,将熵权法和VIKOR法相结合解决椅类家具设计方案的优选问题.结论 通过椅类家具中办公座椅舒适性设计方案的评价过程及结果验证了熵权—VIKOR法能够解决现有设计评价方法主观赋值存在的问题,实现了评价过程的客观化和定量化.     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.     

Early ironwork in Biscay: Survey,excavation, experimentation and materials characterization. An integral study of the mountainside ironworks (ferrerías de monte or “haizeolak”)

ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.     

Mechanism Study on the Wear of CrAlTiN Coated High-Speed Steel Twist Drills Under Dry Cutting Conditions

As demands about environment protection are growing up, dry cutting technology is getting more and more concerns from all over the world. Main works performed here are study on dry cutting performances and wear mechanisms of M2high-speed steel (HSS) twist drills with CrAlTiN multicomponent coatings, which was deposited using magnetron sputter ion plating system, in drilling 45 and 30CrMnSiA steel, and their comparisons to those in drilling the same steel but using monolayer CrN and commercial TiN coated drills. Drilling performances of drills are evaluated mainly through the measurements of width on outer corner flank land and the cutting forces. Results show that performances of CrAlTiN coated drills are better than those of monolayer CrN and TiN coated drills. In drilling 45 and 30CrMnSiA steel, the average tool life of the CrAlTiN coated drills are 17.2 and 11.8 times higher than those of the uncoated drills. Observing wear of the drill with scanning electronic microscope, results show that there is no crack or spallation of the CrAlTiN coatings in wear zones. Main mechanism of the wear here is adhesion.     

Study on Bond Ability of Arc-Spraying Coatings with Different Surface Pretreatment on Cast-Iron

Arc spraying coatings are widely used in various applications, but uncommon in cast iron substrate. Different surface pretreatment technology is tested on substrates of gray cast iron. Surface roughness and residual stress were measured by TR200 and X-ray diffraction analyzer. Influence of different surface pretreatment methods ( dry blasting and fusebond) on roughness and residual stress was analyzed. The arc-sprayed coatings of wire 3Cr13 (φ2mm) on gray cast iron substrate is studied. The microstructure and interface of bonding layer were observed by SEM. The bond strength was taken by tensile test. Results show that bond strength with grit blasting is higher than fuse-bond; it is feasible to make wire 3Cr13 coating with arc spraying on cast iron substrate roughened by grit blasting.     

Structural Characteristics of TiO2 Ceramic Coating by Micro-Plasma Oxidation

TiO2 ceramic coatings with thickness of 20 μm were formed on the surface of pure titanium by micro-plasma oxidation. Their micro-structures were investigated by by using X-ray diffraction and their surface images were detected by using scan electronic microscope. There were three kinds of TiO2 coatings, pure anatase type TiO2 phase, mixed phases consisted of rutile type TiO2 phase and anatase type TiO2 phase, pure rutile type TiO2 phase. The coating surface with the pure anatase type TiO2 phase is rough, while the coating surface with the pure rutile type TiO2phase is smooth. The upper coating surface with the mixed type TiO2 phases is anatase type TiO2 structure and the subsurface of the TiO2 coating is rutile type TiO2structure.     

Evaluation of fatigue life of steel using steel grain size

The insightful discussion of the relationship between the construction of metallographic and fatigue life and proposition of mathematical relationships describing this relationship was conducted in the paper. This paper presents a method for estimating the fatigue life, based on the construction of the microstructural material taking into account the grain size and the participation of ferrite and pearlite phase.