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61.
基于P300信号的脑机接口技术在康复医疗领域具有广阔的应用前景,但P300信号的诱发方式多为视听刺激诱发,容易导致患者视听疲劳,同时也限制了视听障碍患者的使用。针对这些不足,设计一种基于触觉P300的脑控下肢康复机器人系统,在被试的左右食指处各放置一个振动器,通过调整左右手振动器的刺激间隔、刺激时长及刺激比例让P300信号更容易诱发和区分;利用共空间模式算法和支持向量机对信号进行特征提取和分类。被试通过选择关注左手或右手的振动刺激输出不同指令,从而控制下肢康复机器人进行相应动作。实验证明,被试通过感受振动刺激可以轻松诱发脑电中的P300信号,在不进行P300信号平均叠加的条件下,分类准确率为86.50%,既保证了较高的分类准确率,又缩短了指令输出时间。每位被试均可通过下肢康复系统顺利完成训练任务,证明了该方法的可行性。 相似文献
62.
Manuel Herrera Joaquín Izquierdo Idel Montalvo Juan García-Armengol Jos V. Roig 《Mathematical and Computer Modelling》2009,50(5-6):705
Modern data analysis and machine learning are strongly dependent on efficient search techniques. However, in general, further exploration into high-dimensional and multi-modal spaces is needed, and moreover, many real-world problems exhibit inaccurate, noisy, discrete and complex data. Thus, robust methods of optimization are often required to generate results suitable for these data. Some algorithms that imitate certain natural principles, namely the so-called evolutionary algorithms, have been used in different fields with great success. In this paper, we apply a variant of Particle Swarm Optimization (PSO), recently introduced by the authors, to partitional clustering of a real-world data set to distinguish between perioperative practices and associate them with some unknown relevant facts. Our data were obtained from a survey conducted in Spain based on a pool of colorectal surgeons. The PSO derivative we consider here: (i) is adapted to consider mixed discrete-continuous optimization, with statistical clustering criteria arranged to take these types of mixed measures; (ii) is able to find optimum or near-optimum solutions much more efficiently and with considerably less computational effort because of the richer population diversity it introduces; and (iii) is able to select the right parameter values through self-adaptive dynamic parameter control, thus overcoming the cumbersome aspect common to all metaheuristics. 相似文献
63.
64.
Antonio J. Palazzo Kevin B. Jensen Blair L. Waldron Timothy J. Cary 《Journal of Terramechanics》2005,42(3-4):177-191
The Department of Defense (DoD) must constantly balance its military mission and its commitment to stewardship on large tracks of federal land. These military training lands are some of the most intensely used land in the United States, and training requires that vegetation, primarily grasses, be as resilient as possible. The objectives of this study were to evaluate (i) plant establishment and (ii) the effect of light to heavy tank traffic that ranged from zero to four passes on range grasses at the Yakima Training Center, Yakima, Washington. Characteristics measured include the number of 10-cm gaps without plant materials in seeded rows of the target (sown) species, the biomass of the target species, and the percentages of bluegrass colonization, bare ground, and cheatgrass encroachment in tracked and untracked areas. Both stand establishment and the ability to produce rhizomes are associated with the ability to recover after training. The wildryes did not establish well and subsequently had more 10-cm gaps and lower yields than the other introduced species tested. Among the natives, Snake River wheatgrass and western wheatgrass exhibited the most resilience across the different tracking intensities. The largest decline in percentage target species was observed between the two- and four-pass treatments. After five years, cheatgrass was not able to encroach on Snake River wheatgrass, Siberian wheatgrass, and bluebunch wheatgrass plots. Tracking generally reduced the stand of the target species and increased the amount of bare ground. 相似文献
65.
66.
大坂山隧道病害处治工程工艺设计与实证分析 总被引:1,自引:0,他引:1
在国道227线控制工程大坂山隧道病害检测基础上,综合考虑高寒隧道工程地质、水文、气候等自然特征和原隧道施工工艺、施工工法、运营养护等人为因素,分析了渗漏水、衬砌裂缝、低温冻融、混凝土材料劣化等病害演化过程,以及各种不良因素在高寒隧道病害演化发展过程中所起的作用。在病害成因分析的基础上,介绍了大坂山高寒隧道渗漏水、保温、衬砌加固等病害处治的基本原则、思路和具体措施,为后续类似高寒隧道和寒区隧道的病害处治提供经验和借鉴。 相似文献
67.
以连续被动运动(continuous passivemotion,CPM)康复理论为基础,设计一种可以完成对指运动的手指康复训练机械手.在分析人体手指结构及运动特点的基础上,通过动态运动捕捉系统采集手指末端运动轨迹参数,并结合图谱法进行手指康复训练机器人机构的尺度综合.最后,通过Simulink仿真实验验证了其可行性. 相似文献
68.
玄武岩纤维加固震损三维混凝土框架节点抗震试验 总被引:2,自引:0,他引:2
通过5组三维混凝土框架节点试验,研究玄武岩纤维加固后节点的抗震性能.分别进行了模拟地震的预损伤试验、构件加固和加固后的低周反复试验,探讨不同损伤程度、不同裂缝处理方法对三维框架节点抗震性能的影响.通过对节点的滞回&骨架曲线、延性系数、承载力及刚度退化等参数分析可知:玄武岩纤维加固对提高节点承载力作用有限,但对提高抗震性能效果明显,节点的抗震性能恢复并超过了受损前,加固后节点由弱柱强梁转变成了强柱弱梁的破坏形式,说明该加固方法是合理而有效的. 相似文献
69.
Our objective is to study the vocal and laryngeal effect as well as the negative signs and sensations related to the voiced tongue vibration technique (VTVT), regarding the time of performance (from 0 to 7 minutes). Thirty adults (15 men and 15 women) with no vocal complaints nor laryngeal disorders were involved. All subjects underwent laryngostroboscopic and auditory perceptual analysis and answered about the existence of uncomfortable sensations that occurred during the exercise (1, 3, 5, and 7 minutes) and postexercise. For the auditory perceptual analysis, the female group presented better outcomes in the third minute of exercise, whereas in general the male group showed no modification because of performance time. Some men presented a significant change in the parameters involved from the fifth minute on. Men and women showed a gradual increase of undesirable sensations. It is extremely important that the performance time of the VTVT is properly prescribed to provide the expected results, without causing undue injuries to the vocal system. Therefore, we suggest this technique should be recommended for 3 and 5 minutes for women and men, respectively. 相似文献
70.
张春梅 《新疆师范大学学报(自然科学版)》2008,27(3):101-102
足底反射区按摩法是一种安全、简便、经济、无副作用,且有强身防病,自我保健作用,特别是运动后的恢复更是实用方便,产生事半功倍的效果。 相似文献