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1.
Besides entertainment, games have shown to have the potential to impact a broader variety of cognitive abilities. Research has consistently shown that several aspects in cognition such as visual short-memory, multitasking and spatial skills can be enhanced by game play. In a previous study, it was found that playing Monkey Tales, a game aimed at training arithmetic skills, helped second grade pupils to increase their accuracy in mental calculation as compared to paper exercises. In this follow up study we explore whether traditional methods and game training differ in terms of the cognitive processes that both are able to impact. We incorporated standardized measures of working memory and visuo-motor skills. Additionally, the mathematics game was modified and its contents extracted to allow precise comparison between the gaming and paper exercises condition. Thus each single math exercise, type of question (e.g., multiple choice), quantity and order was perfectly matched in the game training and the traditional training conditions. Gains in arithmetical performance, and self-reported measures of enjoyment were also investigated. We found some evidence suggesting that arithmetic performance enhancement induced by game play and paper exercises differ not only in terms of enjoyment but also of working memory capacity improvements.  相似文献   
2.
This paper presents the results of numerical and experimental performance evaluation of the rotary tubular spool valve. The aim of this work is to develop further the novel design of the tubular spool valve by confirming experimentally the validity of the simulation model and its results, thereby proving the valve's potential to represent a feasible and more efficient alternative to conventionally used translation spool valves avoiding the use of two stage valve configurations. In this research the valve performance is assessed through numerical modelling and experimental studies of its metering characteristic and pressure losses. This paper demonstrates that the used valve model yields the results, which agree well with the conducted experimental study. Therefore, validation of the numerical model and the modelling results in the form of theoretical valve characteristics was accomplished. Firstly, the paper presents details of a numerical approach employed to evaluate valve performance and then analyzes the simulation results. Next, the valve performance is experimentally validated by testing a prototype valve on a hydraulic test rig capable of measuring the volume flow rate, pressure levels in up- and downstream lines of the valve across the entire spool angular stroke. Initially, average discrepancies between modelling and test results were 52.46% for the metering and 82.78% for the pressure loss characteristics. Correcting the model geometry aimed at eliminating differences between the valve model and the practically used prototype-test rig system enabled reduction of the error between experiment and modelling by 47.75% for the pressure loss function. This confirmed validity of the simulated characteristics of the valve. The benchmark comparison of pressure losses confirmed average 71.66% energy dissipation reduction compared to the industry-available analogue valve.  相似文献   
3.
ObjectiveTraffic collisions yield a substantial rate of morbidity and injury among child-pedestrians. We explored the formation of an innovative hazard perception training intervention – Child-pedestrians Anticipate and Act Hazard Perception Training (CA2HPT). Training was based upon enhancing participants’ ability to anticipate potential hazards by exposing them to an array of traffic scenes viewed from different angles.MethodTwenty-four 7–9-year-olds have participated. Trainees underwent a 40-min intervention of observing typical residential traffic scenarios in a simulated dome projection environment while engaging in a hazard detection task. Trainees were encouraged to note differences between the scenarios presented to them from separate angles (a pedestrian's point-of-view and a higher perspective angle). Next, trainees and control group members were required to perform crossing decision tasks.ResultsTrainees were found to be more aware of potential hazards related to restricted field of view relative to control.ConclusionsChild pedestrians are responsive to training and actively detecting materialized hazards may enrich child-pedestrians’ ability to cross roads.  相似文献   
4.
文章详细介绍了瑞士霍夫·威施巴德餐厅因苛刻的条件而采用的特殊的设计建造的方法和过程——在基地外的一次预制装配的预演实验,同时也分析了该项目在设计上由于考虑适合装配生产特点而形成的空间效果。  相似文献   
5.
小型低温真空光学实验装置设计   总被引:3,自引:0,他引:3  
屈金祥  陆燕 《红外与激光工程》2006,35(4):464-467,504
为适应未来遥感光学系统研究的需要,研制了一套低温真空实验装置.该实验装置包括低温真空腔体、真空抽气系统、ZYGO干涉仪和防震平台以及监控测温系统.其中的低温真空腔体是针对小型光学元件实验设计的,主要用于测量光学元件的温度场和低温变形,并且把电机产生的局部热量尽可能导出系统.文中还对真空低温腔的关键部件光学窗口和梯形支撑的设计进行了详细分析.  相似文献   
6.
In this work it is presented a study on the residence time distribution (RTD) of particles in a co-current pilot-plant spray dryer operated with a rotary atomization system. A nuclear technique is applied to investigate the RTD responses of spray dryers. The methodology is based on the injection of a radioisotope tracer in the feed stream followed by the monitoring of its concentration at the outlet stream. The experiments were performed during the drying of aqueous suspensions of gadolinium oxide. The RTD responses obtained experimentally presented good reproducibility, indicating that the technique applied is well suited to investigating fluid-dynamics of spray dryers. In addition to the experimental investigation, a mathematical model was used to describe the RTD experimental curves.  相似文献   
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8.
卢勇如  李文平 《江西水利科技》2001,27(3):140-144,148
介绍了江西省抚州市水利产权改革前的基本情况和改革的措施,总结了水利产权制度的经验。  相似文献   
9.
1985年11月在瑞士北部进行了一次以探讨“冷池”条件下的扩散和湍流特征为目的的国际野外大气试验,本文介绍其中的四面体气球示踪实验的结果。一共进行了三次由雷达跟踪的四面体示踪实验,释放了10个四面体球。按多轨迹法和单轨迹法分别估算并比较了其中两次示踪实验得到的水平扩散参数σ_y,探讨了风摆效应的贡献。采用“体源模式”并结合单轨迹法估算了微弱风场不定风向条件下的扩散参数,分析了静风,弱风条件下的水平风向标准差和湍流强度。  相似文献   
10.
数控超声加工的初步工艺试验   总被引:5,自引:1,他引:4  
介绍在经过数控化改造的两坐标超声加工机床上所进行数控超声加工的初步工艺试验,并讨论试验结果。  相似文献   
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