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991.
In current desktop user interfaces, selection is usually accomplished easily with a mouse or a similar two-dimensional locator. In wearable computing, however, controlling two dimensions simultaneously gets significantly harder: a change in one dimension results easily in an undesired change in the other dimension as well when the user is occupied with a parallel task – such as walking. We present a way to overcome this problem by applying one-dimensional selection for graphical user interfaces in head-worn displays. Our new interaction technique allows a wearable computer user to perform object selection tasks easily and accurately. The technique is based on a visible circle on the screen. The user controls the circle, altering its radius with a one-dimensional valuator. The midpoint of the circle is in the middle of the screen. The object currently on the perimeter of the circle is highlighted and can be selected. Our preliminary usability evaluation, applying our custom evaluation method designed especially for walking users, indicates that the proposed technique is usable also when walking. 相似文献
992.
993.
微型构造表征技术在八面河油田的应用 总被引:1,自引:1,他引:0
通过对八面河油田井网密集区及井网稀疏的欠开发区的微构造研究,探讨了微构造表征技术。首先在储层多层次逐级对比的基础上,建立主力油层对比关系;密集井网条件下,则利用钻井资料编制油层顶底微型构造图;对于欠开发地区,通过人机联作自动追踪成图技术,输出2m等值线间隔构造图,建立微构造模型。以微构造模型为基础进行潜力评价,部署关键井寻找优质储量或进行开发动态调整。应用该项技术在八面河油田滚动发现了角15块等断鼻翼部局部高点,增加石油地质储量488×10~4t。 相似文献
994.
介绍了空分装置的分子筛吸附器再生系统的自动控制原理,选用集散控制(DCS)系统实现控制过程,解决了原仪表控制系统的设计、操作和运行上存在问题。新系统更合理、更安全可靠、操作更方便、直观,同时提高了净化工艺的自动化水平。 相似文献
995.
本分析了山西分公司二期CO2压缩机润滑油消耗高的原因,介绍了采取的针对措施以及2002年取得的节能效果,并进一步指出了CO2压缩机的节能空间。 相似文献
996.
Tree-Based Concurrency Control in Distributed Groupware 总被引:3,自引:0,他引:3
We present a novel algorithm, called dARB, forsolving the concurrency control problem indistributed collaborative applications. Themain issue of concurrency control is resolvingthe conflicts resulting from simultaneousactions of multiple users. The algorithmreduces the need for manual conflict resolutionby using a distributed arbitration scheme. Themain advantages of our approach are thesimplicity of use and good responsiveness, asthere are no lock mechanisms. Our algorithmrequires the applications to use a tree as theinternal data structure. This makes itapplication independent and suitable forgeneral collaborative applications. The treerequirement is reasonable since many newapplications use XML (extensible MarkupLanguage) for data representation and exchange,and parsing XML documents results in treestructures. Example applications of thealgorithm, a group text editor and acollaborative 3D virtual environment calledcWorld, are implemented and evaluated in theDISCIPLE collaboration framework. We alsointroduce awareness widgets that users avoidgenerating the conflicting events and help inmanual conflict resolution. 相似文献
997.
This study examined how 1 symbol is selected to control the allocation of attention when several symbols appear in the visual field. In Experiments 1-3, the critical target feature was color, and it was found that uninformative central arrows that matched the color of the target were selected and produced unintentional shifts of attention (i.e., involuntary, initiated slowly, producing long-lasting facilitatory effects). Experiment 4 tested whether such selection is the result of an attentional filter or of a competition bias due to a match of incoming information against integrated object representations stored in working memory. Here, the critical feature was shape and color was irrelevant, but matching color arrows were still selected. Thus, features of objects in working memory will bias the selection of symbols in the visual field, and such selected symbols are capable of producing unintentional shifts of attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Mobile robots can be used in many applications, such as exploration, search and rescue, reconnaissance, security, and cleaning.
Mobile robots usually carry batteries as their energy source and their operational time is restricted by the finite energy
available from the batteries. Therefore, energy constraints are critical to the service time of mobile robots. This paper
investigates the minimum-energy control problem for translational trajectory generation, which minimizes the energy drawn
from the batteries. Optimal control theory is used to find the optimal velocity trajectory in analytic form. To demonstrate
energy efficiency obtainable, we performed simulations of minimum-energy velocity control and compared the results with loss-minimization
control and energy-optimal trapezoidal velocity profiles. Simulation results showed that significant energy savings can be
achieved, of up to 9% compared with loss-minimization control and up to 10% compared with energy-optimal trapezoidal velocity
profile. We also performed an actual robot experiment using Pioneer 3-AT platform to show the validity of the proposed minimum-energy
velocity control. The experimental results revealed that the proposed minimum-energy velocity control can save the battery
energy up to 10% compared with loss-minimization control.
Categories (3): Robot control, (5): RobotMotion Planning 相似文献
999.
基于PLC的焦炉集气管压力专家控制系统 总被引:4,自引:1,他引:3
舒雄鹰 《计算机测量与控制》2003,11(8):583-584,592
通过对焦炉煤气集气管压力系统的分析研究,提出基于专家系统的集气管压力协调控制方案,使得系统在传统PID控制的基础上,能够按照系统实际运行状况智能选择控制策略。全部系统基于西门子S7系列PLC构成,并采用PROFIBUS电缆组成总线型网络。 相似文献
1000.
Thomas Thelin 《Empirical Software Engineering》2003,8(3):309-313
This thesis describes six empirical investigations of two techniques applied to software inspections, namely reading techniques and fault content estimation techniques. The first part of the thesis presents a series of experiments of a novel reading technique called usage-based reading. The second part investigates fault content estimation applied to the software inspection process. The estimation methods used are capture-recapture and curve fitting. 相似文献