利用R语言制作足球运动员跑动热点图的设想

本文将介绍一种利用R语言中的空间分析功能制作简易的足球运动员跑动热点图的设想,以及用R语言制作热点图的优势和不足。     

用硬盘取代DVD驱动器

已经很久没有使用笔记本电脑上的DVD驱动器了吧？那么不要浪费笔记本电脑有限的空间,取出DVD驱动器,将宝贵的空间用来安装一个硬盘驱动器,例如安装一个额外的固态硬盘作为系统盘,并保留原硬盘作为数据盘。     

CIE 1976(L*a*b*)色空间在PVC-U型材颜色测量中的应用

通过对GB 11186-1989《涂膜颜色的测量方法》标准中关于CIE 1964补充标准色度系统、CIE 1976(L*a*b*)色空间的色坐标及色差公式和光与颜色的相关理论的分析,解析了GB/T 8814-2004《门、窗用未增塑聚氯乙烯(PVC-U)型材》中有关型材颜色测量要求,并给出了灰卡级数与总色差的换算关系。     

不卑不亢 男人本色

起亚K5是融合时尚、灵动与力量感,随心所欲享受激情驾驭的高性能全能概念车型。作为精英格调新典范,东风悦达起亚K5以时尚的外观设计、舒适的乘坐空间、卓越的动力水平、动感的精准操控、领先的安全科技以及潮流的科技配置等六大突出优势,设计几乎没有缺点或者不妥的地方,但在原车音响和大多数汽车一样,是非常低端只能听响的配置,达不到“聆听”的要求。没有关系,通过后天的改装,可以给车主一个满意的聆听效果。     

功架十足——奔驰唯雅诺升级摩雷优特声

现在汽车音响改装与前几年夸张改法截然不同,车主多要求尽量减少外观改变,尽量少占车内空间,尽量达到完美的效果。所以对汽车音响改装来说难度更大了。在有限的条件里创造出完美的音响效果,各种器材搭配,安装工艺,调音处理就是音响改装的重中之重。唯雅诺的车主很是随和,与主管一番沟通交流之后,对前后声场进行了升级。     

多媒体在历史教学中的探索与应用

多媒体集文字、图片、音频、动画于一体,突破了课堂时间与空间的限制,生动形象的画面与音效非常符合初中生的思维特征,在声情并茂、动静结合的课堂中,可以最大效率地激发学生的学习兴趣。本文立足初中历史课堂,探索多媒体在历史教学中的优化策略,对于推动课堂改革和促进学生思维发展具有重要的作用。     

Biologically adaptive robust mean shift algorithm with Cauchy predator-prey BBO and space variant resolution for unmanned helicopter formation

Visual tracking technology can provide measurement information for unmanned helicopter formation and thus, more attention is being paid to this research area. We propose a novel mean shift （MS） algorithm that is both adaptive and robust for unmanned helicopter formation and apply it to the leading unmanned helicopter tracking. The movement of an unmanned helicopter is very flexible and changeable, which makes the tracking there of more difficulty than for common targets. In creating an algorithm that can adapt to the acceleration of the unmanned helicopter and estimates both the scale and orientation of the movement changes, we combine the traditional MS with the bio-inspired Cauchy predator-prey biogeography-based optimization （CPPBBO） evolutionary algorithm, and also the space variant resolution （SVR） mechanism of the human visual system （MS-CPPBBO-SVR）. To demonstrate the effectiveness and robustness of the proposed method and justify the importance of the CPPBBO algorithm and SVR mechanism at the same time, a series of comparative exper- iments were carried out. The experimental results of the proposed MS-CPPBBO-SVR method are compared with other competitive tracking methods, such as MS, MS with SVR （MS-SVR）, MS-SVR with several other optimization algorithms, and the robust particle filter algorithm. The experimental results demonstrate that our proposed tracking approach, MS-CPPBBO-SVR, is more adaptive, robust and efficient in target tracking than the other methods.     

Low-complexity optimal spatial channel pairing for AF-based multi-pair two-way relay networks

This paper considers a multi-pair two-way relay system with multi-antenna users and proposes a low-complexity optimal spatial channel pairing （SCP） strategy at the relay station （RS） for such a system. The proposed SCP scheme, following the BD-like beamformer at RS, pairs the uplink spatial subchannels of each user pair with the corresponding downlink spatial subchannels by maximizing sum-rate （Max-SR）. Furthermore, a new mathematical inequality （arrangement inequalities of a product） is developed and applied to obtain sufficient and necessary conditions for achieving Max-SR-SCP. This also yields a simple low-complexity implementation of the proposed SCP in contrast to the NP-hard complexity of the original Max-SR-SCP problem. Simulation results illustrate that the proposed Max-SR-SCP achieves substantial sum-rate gains over other pairing schemes.     

Guaranteed transient performance based control with input saturation for near space vehicles

This paper describes the design of guaranteed transient performance based attitude control for the near space vehicle(NSV)with control input saturation using the backstepping method.To improve the robust controllability of the NSV,the parameter adaptive method is used to tackle the integrated effect of unknown time-varying disturbance and control input saturation.Based on the backstepping technique and parameter estimated outputs,a robust attitude control scheme is proposed for the NSV with input saturation.A novel robust attitude control scheme is then proposed based on a prescribed performance bound(PPB)which characterizes the convergence rate and maximum overshoot of the attitude tracking error.The closed-loop system stability under both the developed robust attitude control schemes is proved using Lyapunov’s method and uniformly asymptotical convergence of all closed-loop signals is guaranteed.Finally,simulation results are given to show the effectiveness of both the proposed robust constrained attitude control schemes.