Re-situating fieldwork and re-narrating disciplinary history in global mega-geomorphology

In 1985, more than thirty geomorphologists, planetary scientists, and remote sensing specialists gathered at a conference center in Oracle, Arizona, to discuss an emerging area of research that they called “mega-geomorphology.” Building on a conference of the same name held in London in 1981, they argued that new techniques of remote sensing and insights emerging from the study of extraterrestrial planets had created opportunities for geomorphology to broaden its spatial and temporal scope. This new approach was, however, neither unproblematic nor uncontested. In the discussions around mega-geomorphology that took place in the mid-1980s, the perceived conflict between the use of remote-sensing techniques to observe phenomena on vast spatial scales, on one hand, and the disciplinary centrality of fieldwork and field experience to geomorphology, on the other, was a recurrent theme. In response, mega-geomorphologists attempted to re-situate fieldwork and re-narrate disciplinary histories in such a way as to make remote sensing and planetary science not only compatible with geomorphological traditions but also means of revitalizing them. Only partially successful, these attempts reveal that the process of adopting a planetary perspective in geomorphology, as in other earth sciences, was neither straightforward nor inevitable. They also show how the field and fieldwork could remain central to geomorphology while also being extensively revised in light of new technical possibilities and theoretical frameworks.     

福建圆形土楼民居空间原型风环境模拟研究

为了进一步研究福建土楼优秀的生态特性,深入研究其室内热环境,土楼民居内部的风环境模拟测试是必不可少的前提步骤.依据福建圆形土楼民居的当地夏热冬暖地区气候环境,提取其典型建筑类型的空间原型,利用PHOENICE分析软件,对在封闭和开敞两种状态下圆形土楼民居内部院落的风环境状况进行了模拟,分析内院空间的通风性能.结果表明:封闭状态下的内院风环境较为稳定,开敞状态下的内院空间通风状况良好,为营造良好的室内热环境提供了适宜条件;福建土楼民居应合理利用自然通风的各种技术措施,适当加入导风板、兜风结构设计等改造设计,实现传统民居的可持续发展.     

天王星的公转影响地球和地球上生物体的行为

指出了地球和地球上生物体的行为,特别是人类的行为,受到天王星运转的影响,支持这一观点的科学证据是非常有限的.一些研究证据表明:全球温度变化、地震的频率和强度、地球上生物体和人类的行为包括流感的流行、股市的趋势和崩盘,甚至战争,与天王星的公转有关.提出了导致这些改变的原因是由于天王星84年的公转周期伴随节律性的磁场方向和强度的变化,这可能节律性地改变地球自转轴倾斜度,结果影响地球本身和地球上生物体的行为.     

基于CBERS CCD数据的鹿洼煤矿塌陷区LUCC检测

本文基于多时相中巴地球资源卫星CBERS CCD数据,以鹿洼煤矿塌陷区为例,利用混合像元分解技术开展土地利用/覆盖变化LUCC检测.分别选取研究区域的2002年、2006年和2010年3个时相的CBERSCCD图像作为遥感数据源,将粒子群优化算法引入到端元提取中,基于线性光谱混合模型提取鹿洼煤矿塌陷区水体、建筑用地、农田和土壤4类地物信息,并对结果进行统计分析.LUCC检测结果表明,2002年至2010年间,鹿洼煤矿塌陷地面积逐年增加,造成大面积农田积水,导致无法进行作物耕种.最后,结合当地政府采取的塌陷地治理措施分析了土地利用变化情况.     

桥梁下高挡墙的设计与稳定计算

在土建工程中经常会使用挡土墙，挡土墙的类型也多种多样，由施工环境、条件而定。本文根据湖南省零陵大道桥梁加宽工程的特点，设计了薄壁式挡土墙和重力式挡土墙。虽然薄壁式挡土墙体积小，但是综合考虑施工难易，工程造价等因素，还是重力式挡土墙较经济实用。     

Effects on Structure and Abrasion Resistance of GCr15 Steel by Surface Gas-Phase RE Diffused Permeation with Laser Melting Solidification

The effects on abrasion resistance and the microstructure of GCr15 steel surface by the compound technology of permeating RE combined with laser melting modification was studied. The results show that after compound treatment, the abrasion resistance of samples has been improved significantly and the weight loss has been reduced to 14% of blank sample; the microstructure has been denser and more uniform than that of untreated; meanwhile, the grain has been refined and the concentration gradients of the elements permeated have been decreased obviously.     

双水分流 各尽其妙——《大地》与《生死疲劳》之比较

中国作家莫言和美籍作家赛珍珠同为以描写中国题材见长的诺贝尔文学奖获得者。莫言的小说《生死疲劳》与赛珍珠的小说《大地》在题材、人物、主题、形式等方面双水分流，各尽其妙。两位作家在中国文学走向世界方面都做了可贵的探索。     

The analysis of the Earth co-orbital motion of Chang’e-2 after asteroid flyby

After the Chang’e-2 spacecraft conducted a successful asteroid flyby,where is it flying to in interplanetary space?This question is answered via an introduction to the Chang’e-2’s flight trajectory after asteroid flyby that is termed Earth co-orbital motion.Based on preliminary analysis using the dynamical systems theory,Poincare′sections concept,and routine optimization techniques,it is now predicted that,from the point of view of orbital mechanics,Chang’e-2 is capable of returning to the vicinity of the Earth in no more than 20 a and might be recaptured by the Earth if appropriate orbital maneuvers are going to be exerted,either by itself or by another spacecraft that captures Chang’e-2.     

多功能厅系统噪声的产生与抑制

多功能厅系统噪声问题常常影响整个系统扩声效果和图象质量 .确保较“干净”的电源向音视频系统供电 ;隔绝由外界噪声产生的干扰噪声 ;音视频系统的信号传输和正确配接是提高线路的抗干扰能力前提 ;建立屏蔽系统和接地网络是抑制电磁噪声基本的有效的方法     

单一稀土处理油菜种子对其吸收镉的影响

探讨了Ｌａ，Ｃｅ，Ｎｄ，Ｐｒ４种单一稀土处理油菜种子，在不同程度Ｃｄ污染土壤上种植后，对油菜生长发育及吸Ｃｄ量的影响。结果表明，Ｃｅ抑制油菜吸收重金属Ｃｄ效果最佳，其次为Ｌａ，随土壤Ｃｄ污染程度加重，Ｎｄ，Ｐｒ对油菜吸收Ｃｄ也表现出一定的抑制效果，同时均不同程度地提高了干物质产量。影响Ｃｄ累积率降低幅度大小顺序为：Ｃｅ＞Ｎｄ＞Ｌａ＞Ｐｒ。