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33.
基于高频通信构建防汛预警应急通信系统浅析 总被引:1,自引:0,他引:1
高频通信亦称短波通信,由电台、天线、馈线、电源系统构成,主要以天波方式传播,是传统的无线电通信方式之一,具有设备简单、机动性大、系统建设快、易操作等优点,是中小型水库高频预警应急通信系统建设众多通信技术的首选解决方案,依据应急为主、性能可靠的目标,建设点对点或一点对多点的语音和低速传输短波应急预警通信链路及其保障方案,可以实现中小型水库的预警应急通信,在安排计划时应优先考虑。 相似文献
34.
研究以羧甲基葡甘聚糖-大豆分离蛋白复合物为主料,卡拉胶和K 组成凝固体系制备植物硬空心胶囊的成型工艺。结果表明:当复合物和卡拉胶的质量比例为80∶20,溶胶温度为80℃,K 浓度为0.02 mol/L,保温时间为30 min,溶胶流动性较好,凝胶强度达到6.53 N/cm2,蘸模成型好,胶囊壁厚达标。 相似文献
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针对防汛抢险自卸汽车运送黏性物料时往往会造成车箱积土、降低自卸车工作效率的问题,研制了箱底积土自动清除装置.实际应用表明:箱底积土自动清除装置简单、实用,自卸汽车加装后,车厢不再有积土,减少了无功消耗,提高了黄河防汛自卸车的工作效率. 相似文献
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In this paper, we develop a semi-autonomous serially connected multi-crawler robot for search and rescue. In large-scale disasters, such as earthquakes and tornadoes, the application of rescue robots to search for survivors under rubble would be beneficial. Snake-like robots (robots composed of serially connected units) are an effective candidate for such robots. Their long body enables them to overcome obstacles, and they can move into narrow spaces because of their thin shape. However, conventional snake-like robots have significant problems with operability. The numerous degrees of freedom of their bodies require complex operation to overcome obstacles, and training is required for the operators. Thus, survivors or community members cannot operate conventional robots to search for victims, despite the availability of such rescue robots. Here, we address this problem and develop a semi-autonomous serially connected multi-crawler robot designed for non-trained operators, such as community members or rescued survivors. It can be controlled easily by a conventional two-channel user interface with levers for turning and straight line motion. To demonstrate the effectiveness of our proposed mechanism, a prototype robot was developed and experiments were conducted. The results confirm that the proposed robot had both higher operability and higher mobility than conventional robots. 相似文献
39.
Farah Faiqah Fazial;Azfaralariff Ahmad;Norziah Mohd Hani; 《International Journal of Food Science & Technology》2024,59(1):276-287
Hard capsules are a frequently used oral medication delivery form. This study aims to evaluate the potential of tilapia fish gelatine as a suitable material for hard capsules, by analysing various gelatine properties under different extraction temperatures (50, 60, 70, and 80 °C) and extraction periods (6 and 12 h). The results showed a range of values for the gelatine yield (22–33% (w/w)), gel strength (141–360 g), molecular weight distribution (140–300 kDa), and amino acid composition (185–220/1000 residues). FG70-12 (296) and FG60-6 (266) were found to have gel strength between 200 and 300 g thus suitable to be used as hard capsule material. Interestingly, the strongest gelatine having 360 g gel strength obtained from FG50-6 (fish gelatine extracted at 50 °C for 6 h) became the essential ingredient for preparing hard capsules because two times dipping was enough to obtain the standard weight and thickness. A slight loss of moisture was identified during drying and rapid dissolution (4–8 min) detected from fish gelatine capsule at pH 6.8 or below. Therefore, hard capsules for pharmaceutical applications could be developed from fish gelatine as an alternative gelatine with similar properties as commercial hard capsules and satisfying the pharmacopoeia standard. 相似文献
40.
通过分析油气长输管道应急抢险非常态施工与常态施工的区别,以及现行计价依据和方式在应急抢险工程结算和审计过程中出现的纠纷和问题,针对性地提出定额修正计价和成本加超额累进比例费用计价两种解决方案.结论显示,在油气长输管道应急抢险施工中综合运用两种方案,能够有效适用其非常态施工具体情况,平衡建设单位和施工单位的期望和诉求,避... 相似文献