多层写字楼施工技术实例分析

本文主要对单体用钢量大、楼层高的多层写字楼的施工进行技术分析,为今后此类型工业建筑施工工艺水平的提高提供成功的经验。     

区间优化提高牧草粗蛋白含量遥感估算精度

牧草粗蛋白含量的估算对于草地营养状况监测以及草地资源可持续利用和管理具有重要意义。针对当前地面遥感与航天遥感的限制,尝试基于航空飞艇高光谱遥感进行牧草粗蛋白含量估算研究,以便更好满足智慧畜牧业的应用需求。针对现有植被生化含量反演不确定性的问题,基于区间划分与判别分析的思想,提出了一种结合等宽区间划分法、逐步判别分析与Fisher判别法相结合的多步骤牧草粗蛋白含量估算模型,以青海省海晏县金银滩草原为研究区进行方案可行性研究。结果表明,提出的模型能够较好的实现牧草粗蛋白含量的精准估算,设定的3种不同划分区间(3区间,5区间和7区间)所对应的全样本检验精度和交叉检验精度分别达到了95%、90%,95%、80%和85%、65%。与传统的逐步线性回归方法相比,估算精度有了明显提高(总体检验精度提高18.7%~70%,交叉检验精度提高20%~62.5%)。3种不同区间模型(3区间,5区间和7区间)所对应的特征波段依次为870、815、802、737、391 nm;988、391、398、405、548 nm;870、815、946、888、839 nm。此外,模型的估算精度与划分区间数量成反比关系,在实际中可以根据不同的应用需求来调节划分区间数量。综上,该文利用航空飞艇高光谱数据实现了牧草粗蛋白含量的精准反演估算,对后期牧场营养状况实时监测以及草地资源可持续利用和管理具有重要的指导意义。     

航天搭载对辣椒SP1主要农艺性状的影响研究初报

研究了航天搭载对TO3、TO4、TO5辣椒自交系SP1代生物学性状的影响,结果表明太空辐射对TO4辣椒的影响最大,其主要性状都发生显著变化,TO3辣椒的开花期、株高、果径、单果重变化也很明显,而太空辐射对TO5辣椒的影响主要集中在果实性状方面。     

无人飞艇应用于超高压输电线路空中巡视可行性研究

由于超高压线路通过区域广,地形、气象、环境等情况复杂,造成了线路运行情况巡视难、掌握难,隐患排查难,故障定位难等一系列难题。开展无人飞艇应用于超高压输电线路空中巡视的研究,利用无人飞行平台及非接触式检测技术解决上述难题,提高输电线路巡视效率、提高巡视手段的科学性,直观、准确地反映输电线路运行情况,及时发现运行隐患,主动错峰维护,是电网运检巡视技术发展的趋势和必然。     

飞船搭载处理对西瓜SP1发芽和生物学特性的影响

研究了飞船搭载西瓜种子SP1的发芽、生物学性状及果实经济性状等.结果表明:飞船搭载对西瓜种子SP1的发芽和生长发育有一定的影响,主要表现在发芽势、成苗率、果实大小、可溶性固形物含量、种皮色等性状.此外,还发现飞船搭载处理后部分植株果实表面产生蜡粉.     

GPS/INS Integrated System and Its Application in the Self-positioning of Airship

To improve the quality of the self-positioning of airship around the earth, and not to lead to the increasing of volume and weight of the positioning systems of airship, the GPS/INS integrated positioning systems are constituted with close integrated pattern. The paper researches its application in the self-positioning of airship around the earth. According to real state of the airship, this paper forms its error state equations and integrates observation equations. Simulation results show that the integrated positioning system not only can pledge its high positioning precision but also can adapt target's quick moving.     

实践八号育种卫星搭载高丹草种子发掘有益突变体

利用卫星搭载高丹草种子,对SP1代种子活力和农艺性状进行诱变效应分析,结果表明：空间条件对高丹草种子损伤较小,SP1代的发芽率、发芽势略有降低,物候期、株高、茎粗、叶片大小等性状变异不明显,分蘖性和叶片数发生较大改变。在SP1代发现丰叶和多蘖2种有益突变类型;进一步研究表明：丰叶型突变为不可遗传的生理变异,多蘖型突变为...     

Assessing the ventilation performance of a naturally ventilated livestock building with different eave opening conditions

In livestock housing permeable windbreak materials are regularly used at eave openings to reduce the adverse effects of windy outdoor conditions on the indoor environment. Two materials generally used for this application include space boarding, i.e. a traditional timber cladding system, and ventilated cladding, i.e. a profiled steel sheeting system with louvers cut into the protruding ribs. In this study computational fluid dynamics (CFD) models were developed to investigate the ventilation performance and thermal environment of naturally ventilated calf buildings with unrestricted, space boarding and ventilated cladding eave opening conditions. The effect of altering the eave opening height on both the indoor environment and ventilation characteristics of the building has also been investigated. It was found that ventilated cladding performed the best in terms of ventilation efficiency and thermal comfort during wind driven ventilation, as the high resistance of the opening condition prevented the short-circuiting of air from the windward to the leeward opening. For high porosity eave opening conditions, increasing the eave opening height was found to decrease the average air velocity at animal level due to a change in size and location of the primary air recirculation zone. It was also found that the resistance and the height of an eave opening determine whether or not the leeward eave opening acts as an air inlet.