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101.
一种新的覆盖粗糙集及其模糊性度量 总被引:2,自引:0,他引:2
在覆盖近似空间中定义了一类新的模糊集,给出了该类模糊集的模糊性度量,讨论模糊集及其模糊度量的性质,最后通过实例给出直观解释. 相似文献
102.
Dharani Perera R. T. Jim Eales Kathy Blashki 《Universal Access in the Information Society》2009,8(2):77-88
For people with upper limb disabilities visual art is an important activity that allows for expression of individuality and
independence. They show remarkable endurance, patience and determination to adapt their remaining capabilities to create visual
art. There are significant advantages of digital technologies in assisting artists with upper limb disabilities. Paralinguistic
voice recognition technologies have proven to be a particularly promising mode of interaction. Despite these benefits, technological
support for people with upper limb disabilities to create visual art is scarce. This paper reports on a number of case studies
of several artists with upper limb disabilities. These case studies illustrate the struggles they face to be creative and
also show the significant advantages of digital technologies in assisting such artists. An investigation into people’s ability
to use the volume of their voice to control cursor movement to create drawings on the screen is also reported. With motivation,
training and practise, use of volume to control drawing tasks shows great promise. It is believed that paralinguistic voice
has wider implications beyond assisting artists with upper limb disabilities, such as: an alternative mode of interaction
for disabled people to perform tasks other than creating visual art, alternative mode of interaction for hands busy environments
and as a voice training system for people with speech impairments. 相似文献
103.
本文阐述了星型网络拓扑结构的特点,并结合图论与关系矩阵的相关知识提出了链路上界和波动系数的概念,对解决智能大厦综合布线系统设计施工中存在的网络拓扑结构问 题提出了建议。 相似文献
104.
Letf: {0,1}
n
{0,1}
m
be anm-output Boolean function inn variables.f is called ak-slice iff(x) equals the all-zero vector for allx with Hamming weight less thank andf(x) equals the all-one vector for allx with Hamming weight more thank. Wegener showed that PI
k
-set circuits (set circuits over prime implicants of lengthk) are at the heart of any optimum Boolean circuit for ak-slicef. We prove that, in PI
k
-set circuits, savings are possible for the mass production of anyFX, i.e., any collectionF ofm output-sets given any collectionX ofn input-sets, if their PI
k
-set complexity satisfiesSC
m
(FX)3n+2m. This PI
k
mass production, which can be used in monotone circuits for slice functions, is then exploited in different ways to obtain a monotone circuit of complexity 3n+o(n) for the Neiporuk slice, thus disproving a conjecture by Wegener that this slice has monotone complexity (n
3/2). Finally, the new circuit for the Neiporuk slice is proven to be asymptotically optimal, not only with respect to monotone complexity, but also with respect to combinational complexity. 相似文献
105.
《Calphad》2023
RuO4 oxide appears much less stable than RuO2(s) in the Ru–O binary system with a melting point close to room temperature and a certain propensity to vaporize or decompose at low temperatures. Ab initio simulations in the framework of density functional theory (DFT) on RuO4(s) are performed to analyze the cubic and monoclinic structures and to evaluate the heat capacities at low temperatures. Then, a critical evaluation of thermodynamic data from calorimetry and vapor pressure determinations - was carried out coupled with ab-initio calculations to propose new thermodynamic data: the entropy.S° (RuO4, s, cubic, 298K) = 132.7 J·K−1mol−1 and formation enthalpy.ΔfH° (RuO4, s, cubic, 298K) = −252.4 ± 5.5 kJ mol−1. 相似文献
106.
针对博弈对抗环境下利用快速采样雷达进行非合作目标跟踪带来的有色噪声和未知干扰共存问题, 本文提出有色量测噪声下带广义未知扰动的随机动态系统递推上限滤波. 这里, 有色量测噪声用于描述由于快速采样或持续干扰带来的噪声相关性, 广义未知扰动用于建模博弈对抗对雷达观测带来的异常影响(先验信息缺失). 针对所考虑系统, 通过参数优化实现状态估计误差协方差上限(而不是理论值)的在线递推, 提出有色噪声下上限滤波(CU-BF), 给出状态估计误差协方差最小上限的近似实现, 讨论了所提CUBF的存在性条件. 在具有时变未知扰动和有色量测噪声的目标跟踪仿真中验证了所提方法的有效性. 相似文献
107.
Pin-Lin Liu 《中国工程学刊》2016,39(2):150-158
This paper concerns managing the robust exponential stability problem of uncertain Takagi–Sugeno fuzzy systems with time-varying delay by employing a further improved integral inequality matrix approach. Based on the linear matrix inequality (LMI) approach, delay-dependent robust exponential stability criteria have been developed. By taking the relationship among the time-varying delay, its upper bound and their difference into account, some less conservative LMI-based delay-dependent robust exponential stability criteria are obtained without ignoring any useful terms in the derivative of Lyapunov–Krasovskii functionals. Maximum allowable upper bound for time-varying delays is determined. Numerical examples are provided to show that the obtained results significantly improve the allowed upper bounds of delay size over some methods existing in the literature. 相似文献
108.
Vladimir Z. Kresin Stuart A. Wolf Yu. N. Ovchinnikov 《Journal of Superconductivity》1996,9(3):329-333
The value of the critical temperature of the cuprates correlates with the doping level and is affected by the interplay of two competing factors: (1) the increase in carrier concentration, and (2) the pair-breaking effect of magnetic impurities. An analysis of the temperature dependence of the critical field leads to the conclusion that magnetic impurities are present even in a sample with the maximum observed value ofT
c.A new parameter, intrinsicT
c (T
cintr), which is its value in the absence of magnetic impurities, is introduced. The maximum value ofT
cintr, which corresponds to the maximum doping level, appears to be similar for different cuprates and to be equal to 160–170 K. This is the upper limit ofT
c in the cuprates. 相似文献
109.
This paper considers the problems of formation and obstacle avoidance for multiagent systems.The objective is to design a term of agents that can reach a desired formation while avoiding collision with obstacles.To reduce the amount of information interaction between agents and target,we adopt the leader-follower formation strategy.By using the receding horizon control (RHC),an optimal problem is formulated in terms of cost minimization under constraints.Information on obstacles is incorporated online as sensed in a limited sensing range.The communication requirements between agents are that the followers should obtain the previous optimal control trajectory of the leader to each update time.The stability is guaranteed by adding a terminal-state penalty to the cost function and a terminal-state region to optimal problem.Finally,simulation studies are provided to verify the effectiveness of the proposed approach. 相似文献
110.
The spectral properties of the incidence matrix of the communication graph are exploited to provide solutions to two multi-agent control problems. In particular, we consider the problem of state agreement with quantized communication and the problem of distance-based formation control. In both cases, stabilizing control laws are provided when the communication graph is a tree. It is shown how the relation between tree graphs and the null space of the corresponding incidence matrix encode fundamental properties for these two multi-agent control problems. 相似文献