机动目标跟踪源代码，粒子滤波
主要是关于基于粒子滤波器的目标跟踪算法及实现。粒子滤波是以贝叶斯推理和重要性采样为基本框架。贝叶斯推理就是类似于卡尔曼滤波的过程。而卡尔曼滤波是线性高斯模型，对于非线性非高斯模型，就采用蒙特卡洛方法（Monte Carlo method,即以某时间出现的频率来指代该事件的概率）。采用一组粒子来近似表示系统的后验概率分布，然后使用这一近似的表示来估计非线性非高斯系统的状态。（粒子滤波从一定程度上，属于卡尔曼滤波的拓展）
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.000939s ]
SELECT `a`.`aid`,`a`.`title`,`a`.`create_time`,`m`.`username` FROM `jrk_downrecords` `a` INNER JOIN `jrk_member` `m` ON `a`.`uid`=`m`.`id` WHERE `a`.`status` = 1 GROUP BY `a`.`aid` ORDER BY `a`.`create_time` DESC LIMIT 10 [ RunTime:0.086671s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.000900s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.001149s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.000972s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.003052s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.000845s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.003807s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.018427s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.001020s ]
UPDATE `jrk_articles` SET `hits` = 2 WHERE `id` = 20662 [ RunTime:0.028921s ]
