Monitoring of Vibration Exposure for Taxi Drivers

Vibration Exposure of taxi driver has not only impact on driverg health but the safety of driving. The constantspeed running test and a monitoring test in actually situationare done. The taxi driver vibration exposure testing data is analyzed, and it is found that the vibration exposure evaluation of constant speed test cant satisfy the actually situation. At last, animpersonalassessment is done according to the vibration exposure evaluation standard of ISO2631.     

驾驶座悬架的理想非线性弹性特性及实现方法

研究了驾驶座悬架的理想非线性弹性特性及几种实现给定非线性弹性特性的结构原理及实验结果。     

蚂蚁和真菌关系的研究进展

蚂蚁是陆地生态系统中种类和数量最为丰富的动物类群,与其他许多物种都具有广泛而复杂的联系;其中一些类群与真菌形成古老的共生关系,成为著名的菌食性昆虫.蚂蚁与真菌间的共生关系已具有长达5 000多万年的协同进化历史,迄今已知的与真菌共生的蚂蚁主要为爱特蚁族和火蚁族的种类,而蚂蚁培养的真菌主要属于担子菌亚门伞菌目环柄菇科白环蘑属和白鬼伞属,少数种类属于子囊菌亚门和半知菌亚门.蚂蚁和真菌间形成一个高度进化的单元,相互间存在营养、生理方面以及免疫互助等特点;蚂蚁与真菌间的关系已成为生态学、进化学研究的热点.结合笔者在蚂蚁与真菌关系方面研究的部分进展,对蚂蚁与真菌的关系及其对真菌的利用方式等进行总结和概述,以期为我国在蚂蚁与真菌间关系研究方面提供信息和思路.     

TRUCK TRANSPORTING SYSTEM

COMPOSITlONOFTRUCKTRANS-PORTlNGSYSTEMTrucktransportingsystcl11x`as1nainlycomposedoftfanspoFtingthecksandtransp0rt-ingroads.TransportingtrUckandroadman-agementwasacomplicatedandconnectedsystem.Inthesystcm,theproductivity.oftral1sportingtrucksdependedontheconditionsoftransportingroads.Andtl1eusingtimeoftransportingtrucksalldroadsdepcndedontheirusingconditions.Now,themainproblemsofmanagementoftrllcktransportingsystemweretostudyanddeterminetl1emanagingmcthodandcnsuringn1easurcofhigl…     

Variability in soils and vegetation associated with harvester ant (Pogonomyrmex rugosus) nests on a Chihuahuan Desert watershed

The effects of harvester ant (Pogonomyrmex rugosus) nests on the density and cover of spring annual plants and on soil characteristics were measured at three locations characterized by different soils and dominant vegetation on a desert watershed. There were few differences in vegetation and soils associated with harvester ant nests at locations at the base of the watershed where brief periods of flooding and sediment deposition occur at periodic intervals. At mid-slope locations, there were significant increases in total nitrogen, inorganic phosphorus, and cover (biomass) of four species of spring annuals at the edges of nest disks when compared with reference sites. The spring annuals that exhibited increased cover were species that increase biomass as a function of available nitrogen. At a clay-loam, Scleropogon-Hilaria, grassland site, there were significant reductions in the concentrations of Ca²⁺ and Mg²⁺, significant increases in nitrate and total nitrogen, but a significant increase in cover in only one species of annual plant. The data demonstrate that the effects of ants on soil properties and vegetation vary with site location and soil type.     

The spatial distribution of diversity between disparate taxa: Spatial correspondence between mammals and ants across South Florida,USA

Gap Analysis takes a proactive landscape-level approach to conserving native species by identifying nodes of high biological diversity. It uses vertebrate species richness as an index of overall biological diversity. However, it remains unknown whether or not the spatial distribution of vertebrate diversity corresponds with the diversity of other taxa. We tested whether landscape-level diversity patterns corresponded between a vertebrate and an invertebrate taxon, mammals and ants, across the southern half of the Florida peninsula, USA. Composite digital maps with a 30-m spatial resolution were produced for each taxon. Spatial correspondence between the taxa was determined by normalizing and then subtracting the composite maps. There were large areas of spatial correspondence – indicating that richness between mammals and ants was similar over much of southern Florida. However, spatial correspondence occurred where the richness of both taxa was low or moderate, and areas with the highest species richness (highest 20%) for each taxon, the explicit focus of Gap Analyses, corresponded over only 8752 ha. Gap Analysis provides a much needed assessment of landscape-level diversity patterns and proactive reserve design, but it must be explicit that the results are applicable for vertebrate diversity, which does not necessarily correspond with diversity patterns of other taxa. The two taxa investigated differ by orders of magnitude in the scale that they perceive their environment, and it is likely that diversity hotspots vary as the scale of investigation – and the taxa mapped – vary.     

S3C2410A中STN型LCD显示驱动的实现

通过对LCD显示原理的分析和对嵌入式芯片S3C2410A中LCD控制器的研究,设计了STNLCD的硬件驱动电路和软件驱动程序,完成了在S3C2410A中对STN LCD驱动的设计.实验结果显示LCD上图像显示稳定清晰,达到设计要求.该设计可用于大部分嵌入式芯片对STNLCD的驱动,是嵌入式系统中实现LCD驱动的一套较好解决方案.     

Seed removal by ants,birds and rodents in a woodland savanna habitat in Zimbabwe

Seed removal from bait stations was studied in miombo habitat in western Zimbabwe. Previous studies of seed predation in southern Africa have largely been conducted in desert ecosystems. However, this woodland-savanna habitat is more mesic and has relatively predictable rainfall patterns. The experiment was conducted in grassy and woody microhabitats in the hot, dry season and early wet season, and followed a year in which precipitation was 69% of the long-term average. Birds removed the greatest quantity of seeds, followed by ants and then rodents. Previous studies in northern hemisphere mesic environments emphasize the importance of rodents and minor role of invertebrates in seed predation. Although our site appears to have more in common with southern hemisphere desert sites than with northern hemisphere mesic sites, we recognize thatour results are likely to reflect a lower limit of consumption by rodents.     

A synthesis on the impact of non-native conifer plantations on ant and beetle diversity in north-western Patagonia

Softwood forestry with non-native tree species is increasing worldwide and especially in many developing countries of the Southern Hemisphere. Tree plantations are beneficial in environmental and socioeconomic aspects, but at the same time there are recognised costs associated with afforestation. Our aim was to revise the existing information on the impact of exotic conifer plantations in north-western Patagonia on insect biodiversity. A total of five studies were selected and, in these, not every insect group responded in a similar manner to the habitat replacement. There was a tendency towards a reduction in abundance and species richness of several insects inside pine plantations. This change in abundance and richness was especially evident for ant assemblages and when pine plantations were dense. Beetle assemblages, in turn, showed diverse responses to the replacement of native vegetation with forests depending on the native habitat matrix. Our findings confirm that practices that reduce tree density (via thinning or during plantation) should be recommended to minimise their impact on insect biodiversity in north-western Patagonia. The consistent behaviour of ant assemblages, coupled with their abundance, ease to sample and unambiguous taxonomy make them reliable candidates for long-term monitoring of the impact conifer forestation in north-western Patagonia, as well as probably in other regions of the world in which non-native pines replace natural environments.     

基于车辆坐标系的闭环系统驾驶员模型研究

建立了基于旋转坐标系和车辆坐标系的单点预瞄横向偏差驾驶员模型,圆形路径的仿真计算结果表明,这两种驾驶员模型都能很好地跟踪目标路径,但对车辆的操纵行为却有明显的差异。基于车辆坐标系的驾驶员模型对车辆的控制接近于驾驶员的实际操纵行为,用这类驾驶员模型来进行汽车操纵稳定性的仿真评价才是合适的。