美国新桥水水电站的掺气水轮机

杜克（Duke）能源公司卡罗莱纳（Carolinas）州有限责任公司计划为桥水（Bridgewater）工程装机28 MW的新建水电站安装掺气水轮机。期望这些为现场情况专门设计的水轮机可使杜克能源公司提高工程下游水流中的溶解氧含量,同时也使效率损失降到最小。     

气候变化和跨国界水资源管理

跨国界水资源的共享一直是人们主要关心的问题。在很多地区,没有足够的水资源满足人们的用水需求。随着全球气候变暖,人们在水资源的获得、分配和共享等方面面临越来越多的压力和困难。当水资源跨越国界边境时,这些问题会变得更加尖锐。对影响获取水资源的主要因素,以及有助于解决跨国界水资源冲突的跨国界协议或合约的内容进行了介绍和分析。     

高效打印 屏幕立现 三星ML-1911黑白激光打印机

在针对企业用户进行的抽样调查中我们发现,目前在小型部门级办公环境中．虽然大多都配有多功能打印一体机．但是黑白激光打印机依然承担着最大份额的文档输出任务。这类单功能产品使用范围最广却也最容易被用户所忽视——大家从来不认为这种功能单一的产品还能玩出什么花活儿!     

探索人体奥秘

还记得自己的身体结构是什么模样的吗?万一忘了话,不妨打开浏览器,谷歌为您准备了一节生动的课堂,向你逼真展示人体的奥秘。记得在中学的生物课堂,讲台上老师要不是念天书,就是拿出一张张的图纸来做"生动"讲解,偶尔还会弄几张幻灯片做解剖讲析,不过我最喜欢的还是实验室里头的一副骷髅,那比较简单比较真实,有助我联想思考。     

M9只是个传说

曾受到人们热切期待,并被喻为新一代国产机王的魅族M9,上市后马上在坊间掀起了种种负面消息,有人叫骂的同时也有人站出来为其说好话。究竟网上的这些流言有多少可信?让我们共同客观分辨之。     

Sex-related differences in foot shape

The purpose of the study was to investigate sex-related differences in foot morphology. In total, 847 subjects were scanned using a 3-D-footscanner. Three different analysis methods were used: (1) comparisons were made for absolute foot measures within 250-270 mm foot length (FL); (2) and for averaged measures (% FL) across all sizes; (3) the feet were then classified using a cluster analysis. Within 250-270 mm FL, male feet were wider and higher (mean differences (MD) 1.3-5.9 mm). No relevant sex-related differences could be found in the comparison of averaged measures (MD 0.3-0.6% FL). Foot types were categorised into voluminous, flat-pointed and slender. Shorter feet were more often voluminous, longer feet were more likely to be narrow and flat. However, the definition of 'short' and 'long' was sex-related; thus, allometry of foot measures was different. For shoe design, measures should be derived for each size and sex separately. Different foot types should be considered to account for the variety in foot shape. Improper footwear can cause foot pain and deformity. Therefore, knowledge of sex-related differences in foot measures is important to assist proper shoe fit in both men and women. The present study supplements the field of knowledge within this context with recommendations for the manufacturing of shoes.     

Figure-ground separation by cue integration

This letter presents an improved cue integration approach to reliably separate coherent moving objects from their background scene in video sequences. The proposed method uses a probabilistic framework to unify bottom-up and top-down cues in a parallel, "democratic" fashion. The algorithm makes use of a modified Bayes rule where each pixel's posterior probabilities of figure or ground layer assignment are derived from likelihood models of three bottom-up cues and a prior model provided by a top-down cue. Each cue is treated as independent evidence for figure-ground separation. They compete with and complement each other dynamically by adjusting relative weights from frame to frame according to cue quality measured against the overall integration. At the same time, the likelihood or prior models of individual cues adapt toward the integrated result. These mechanisms enable the system to organize under the influence of visual scene structure without manual intervention. A novel contribution here is the incorporation of a top-down cue. It improves the system's robustness and accuracy and helps handle difficult and ambiguous situations, such as abrupt lighting changes or occlusion among multiple objects. Results on various video sequences are demonstrated and discussed. (Video demos are available at http://organic.usc.edu:8376/ approximately tangx/neco/index.html .).     

电弧闪光

电弧闪光与触电相比有很大的不同。当一个人触电的时候,电流会在人体的敏感组织（主要是神经）间通过,从而产生影响。电弧闪光通常在空气导电时产生,其的主要成因是两个接触的导体再次分离时将电流拉出。当电弧产生时,形成的缺口内充满了电离子,其数量迅速上升,尤其是在高压／低阻的供电情况下,例如电力输送线,这种情况更加明显。任何大于50V的电路都有可能产生电弧闪光。     

很小很强大 打造超迷你平台客厅电脑 系列专题之一 平台搭建篇

“好小啊！”几乎所有人第一次看到NVIDIA离子平台的时候,都会发出这样的惊呼,然后人们会有三种反应,要反围观之后走开,要么打听哪里可以买到,而我们发烧级DLYer则会想：它为什么这么小,我们能自己搭建一台出来吗？为了实现打造超迷你平台客厅电脑的愿望,     

The effect of time of day on injury patterns amongst adolescents in Australia

Labour force participation of adolescents in Australia is growing at an unprecedented rate. This increased participation is coupled with a growing realisation of the vulnerability of adolescents in the labour market in terms of occupational injury. Despite recent evidence that time of day may be an important determinant of adolescent injuries, the impact of non-standard and night work on adolescent injury rates has received scant attention to date. The current study addresses this shortcoming by examining injury patterns of 3201 working adolescents in Queensland. Results revealed that female adolescents are 2.5 times more likely to sustain an injury on day shift and 4.71 times more likely to sustain an injury on night shift than their adult counterparts when total work hours are taken into consideration. Similar results were found for male adolescents with an injury to work hours ratio of 2.19 on day shift and 3.05 on night shift. These findings point to the value of considering the temporal pattern of adolescent work in future research aimed at minimising injuries at work and improving the work experience of tomorrow's workforce.