科创中国

中医诊疗研究引入机器学习方法存在交互性差和特征值离散性两大缺陷.引入基于随机森林(Random Forest,RF)的可视化技术,对原始数据进行基于RF的特征变换,使样本在新特征空间的类可分性增强;采用主坐标分析法对变换后的数据进行降维,将高维数据的关系信息变换到适合人类视觉认知的低维空间里;在低维空间里采用散点图和平行坐标图对数据进行可视化.在中医慢性胃炎数据集上的实验结果表明,通过RF处理后,各类数据聚集在不同的区域空间中,呈现良好的可分性.这些图形图像视觉信息能帮助用户准确理解数据集的分布规律以及隐含的发展趋势,进而深入探讨这些信息蕴含的中医学意义.

分析了南方森林虫害发生原因和防治现状,在此基础上提出了防治森林虫害的策略和措施,对构建森林虫害防治体系提出了建议.

光照是树木生长需要的重要资源,是树木生长仿真计算中必不可少的因素.但在森林演化的计算机模拟中,由于光照模拟的复杂性,使得光照模型的计算量十分巨大.本文采用了光照指数(Gap Light Index,GLI)为因子的光照模型,并针对该模型开展了快速计算研究.由于该模型计算中存在着大量限制计算效率的几何求交运算,本文根据光照指数与植物暴露面积所具有的共同特点,提出采用基于暴露面积的计算方法来近似拟合GLI的值,并在并行计算架构CUDA上实现了该算法.最后通过不同实验比较,验证了本文提出的方法针对较大的树木规模,在保证较小误差率的前提下,获得了比GPU并行求交方法快数十倍以上的加速比.

如今英国出现了一股森林抢购风潮,这股风潮不仅来自人们对小熊维尼森林历险记的怀念之情,更出于对环境保护的日益关注."小片林地所有者"协会的成员特雷西·派普勒亲眼见证该组织人数在短短三年内达到了近千人."面对气候变化和全球发生的种种问题,拥有自己的林地让你有能力去做一些事情."特雷西说.

Because antipredator behaviours are costly, the threat-sensitive predator avoidance hypothesis predicts that individual animals should express predator-avoidance behaviour proportionally to the perceived threat posed by the predator. Here, we experimentally tested this hypothesis by providing wild passerine birds supplemental food (on a raised feeding platform) at either 1 or 4 m from the edge of forest cover (potential refuge), in either the presence or absence of a nearby simulated predation threat (a sharp-shinned hawk Accipiter striatus model). Compared with the control treatment, we observed proportionally fewer bird visits to the food patch, and the birds took longer to re-emerge from forest refuge and return to feed at the food patch, after the hawk presentation than before it. The observed threat-sensitive latency-to-return response was stronger when the food patch was further away from the nearest refuge. Overall, our results are consistent with the predictions of the threat-sensitive predator avoidance hypothesis in that wild passerine birds (primarily black-capped chickadees Poecile atricapillus) exhibited more intense antipre- dator behavioural responses with increasing level of apparent threat. The birds were thus sensitive to their local perceived threat of predation and traded-off safety from predation (by refuging) and foraging gains in open habitat in a graded, threat-sensitive manner [Current Zoology 60 (6): 719-728, 2014].

2014年3月4日下午,2015米兰世博会万科馆新闻发布会在北京意大利驻华大使馆召开.此次米兰世博会的主题是"滋养地球,生命的能源",万科馆以"食堂"为展览主题,以"媒体森林"的形式,用近300块不规则摆放的屏

莽山国家森林公园地处湘粤交界的南岭山脉中段,拥有30万亩森林.是珍稀动植物的乐园.全园生物种类丰富,有高等植物2600多种、脊椎动物300多种、昆虫8000多种.在这些物种当中,包括国家重点保护野生植物23种、重点保护野生动物33种.丰富的物种生物资源、良好的生态环境,为开展科普活动提供了坚实基础和广阔空间.

Recursion?by?herbivores?is?the?repeated?use?of?the?same?site?or?plants.?Recursion?by?wild?animals?is?rarely?investigated?but?may?be?ubiquitous.?Optimal?foraging?theory?predicts?site?recursion?as?a?function?of?the?quality?of?the?site,?extent?of?its?last?use,?and?time?since?its?last?use?because?these?influence?site?resource?status?and?recovery.?We?used?GPS?collars,?behaviour?and?site?sampling?to?investigate?recursion?to?foraging?sites?for?two?elephant?Elephas?maximus?borneensis?herds?in?the?Lower?Kinabatangan?Wildlife?Sanctuary,?Borneo,?over?a?12?month?period.?Recursion?occurred?to?48?out?of?87?foraging?sites?and?was?most?common?within?48?hours?or?between?151-250?days,?indicating?two?different?types?ofrecursion.?Recursion?was?more?likely?to?occur?if?the?site?had?previously?been?occupied?for?longer.?Moreover,?the?time?spent?at?a?site?at?recursion?was?the?same?as?the?time?spent?at?the?site?on?the?first?occasion.?The?number?of?days?that?had?passed?between?the?first?visit?and?recursion?was?also?positively?correlated?with?how?much?time?was?spent?at?the?site?at?recursion.?Habitat?type?also?influenced?the?intensity?of?site-use,?with?more?time?spent?at?recursion?within?riverine/open?grass?areas?along?forest?margins?compared?to?other?habitat?types.?Recursion?is?a?common?behaviour?used?by?the?elephants?and?its?pattern?suggests?it?may?be?a?foraging?strategy?for?revisiting?areas?of?greater?value.?The?qualities?of?recursion?sites?might?usefully?be?incorporated?into?landscape?management?strategies?for?elephant?conservation?in?the?area?[Current?Zoology?60?(4):?551-559,?2014].

云岫谷风景区坐落在密云县东北部雾灵山山麓.位于新城子遥桥谷村,雾灵湖西侧,距县城70公里,距北京市132公里,东临雾灵山森林公园,西毗司马台长城,是北京地区独一无二的集狩猎、度假、娱乐、科考于一体的多功能旅游区,这里有独特的自然景观和人文景观.最高海拔达2116米,植被覆盖率95%.奇峰、怪石、洞穴、峡谷、溪流、潭瀑、

福建三明是全国为数不多的百万担优质烟叶产区之一,地处福建西北部,闽江上游,武夷山脉和戴云山脉之间,森林覆盖率达76.8%,素有绿色宝库之美誉,生态条件极其适应优质烟叶生产.目前,三明烟区常年种烟面积40~45万亩,收购烟叶100~120万担.近年来,三明烟区紧