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随着氢气的广泛应用,研制高效的氢气探测仪是非常有意义的。在氢气浓度达到爆炸极限前,提前预测可避免危险事故的发生,确保人员和设备的安全。氢气探测仪对确保氢气的安全使用非常重要,本文简要介绍了氢气探测仪的发展状况和技术性能。技术性能包括测量范围、响应和复原时间、环境温度、压力和相对湿度、功率消耗、使用寿命等。 相似文献
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In data streams or web scenarios at highly variable and unpredictable rates, a good join algorithm should be able to "hide" the delays by continuing to output join results. The non-blocking algorithms allow some tuples to be flushed onto disk, with the goal of producing results continuously when data transmission is suspended. But state-of-the-art algorithms have trouble with the constraint of allocated memory. To make better use of memory, a novel non-blocking join algorithm based on hash-merge for improving query response times is proposed. The reduced data structure of in-memory tuples helps to improve memory utility. A replacement selection tree is applied to adjust memory by expanding or shrinking the size of the tree and separates one external join transaction into multi-subtasks. In addition, a cost model to estimate task output rate is proposed to select the in-disk portion that promises to produce the fastest results in the external join stage. Experiments show that the technique, with far less memory, delivers results faster than the three non-blocking join algorithms (XJoin, HMJ and RPJ), with up to almost two-fold improvement in reliable network and one order of magnitude improvement in unreliable network in terms of the number of the reported tuples. 相似文献
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现代摩托车用氧传感器(Oxygen Sensor)的主要功能是监测发动机排放中氧的含量,调节空燃比。如图1所示是美国德尔福公司生产的各种摩托车用氧传感器,它是现代摩托车闭环反馈控制系统中必不可少的元件,是EFI电脑ECU监控发动机混合气空燃比始终收敛于理论空燃比(14.7:1)附近的唯一控制依据;同时也是OBD中必不可少的关键性部件,是确保摩托车在整个使用寿命期内排放不超标的关键传感器,为监管摩托车排放达标和维修提 相似文献
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为满足未来的公路排放标准,有必要对重型发动机进行瞬态优化。精确EGR控制对降低发动机排放,满足未来的排放法规很有用。以降低瞬态原始排放为目标,EGR系统的响应时间必须缩短。 相似文献
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合理选择减摇鳍液压随动系统响应要求,能够有效地提高减摇鳍液压随动系统的性价比.从理论上分析减摇鳍装置的相位误差对减摇效果的影响,并应用这些理论确定减摇鳍液压随动系统的响应要求. 相似文献
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Anytime算法能够折衷解的质量和计算时间,被广泛地用在实时人工智能系统中.为保证在截止期到来之际得到的解是可接受的,Anytime算法应能够足够快地响应环境的变化,输出当前最优解.文中描述了环境状态变化模型和随机截止期模型,探讨了在变化的领域中Anytime算法的最优响应时间. 相似文献
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