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81.
Typically characterizing home made explosives (HMEs) requires many large scale experiments, which is prohibitive given the large number of materials in use. A small scale experiment was developed to characterize HMEs such as ammonium nitrate‐fuel oil mixtures. A microwave interferometer is applied to small scale confined transient experiments, yielding time resolved characterization of a failing detonation that is initiated with an ideal explosive booster charge. Experiments were performed with ammonium nitrate and two fuel compositions (diesel fuel and mineral oil). It was observed that the failure dynamics were influenced by factors such as the chemical composition, confiner thickness, and applied shock wave strength. Thin steel walled confiners with 0.71 mm wall thickness experienced detonation failure and decoupling of the shock wave from the reaction zone. Confiners with a wall thickness of 34.9 mm showed a decrease in propagation speed and a steady reactive wave was achieved. Varying the applied shock strength by using an attenuator showed corresponding changes in the initial overdriven reactive wave velocity in the HMEs. The distance to detonation failure was also shown to depend on the attenuator length when thin wall confinement was used. This experimental method is shown to be repeatable and can be performed with little required material (about 2 g). The data obtained could be useful to model development and validation, as well as quantifying detonability of materials.  相似文献   
82.
为了提升家庭智能用电管理系统的计算效能,使用时序分析算法,将远程抄表实时费控电能表采集的1s步长的电流、电压数据序列,整理成5列录波图,并利用线性重投影算法形成可供神经网络识别的时序序列,使用加权卷积多列神经网络进行挖掘,将用户每1s步长的用电量信息分解成空调、插座、照明等负荷用电量信息,最终形成家庭智能用电管理系统的数据分解展示功能。经过与针对上述负荷单独安装电能表的实测数据进行对比,发现该改进智能用电优化算法得到的用电量分解结果,与实测结果的误差率均为5.8~6.0%之间。  相似文献   
83.
大口径弯管国产化技术问题探讨   总被引:1,自引:0,他引:1  
本文从国内我油气管道大口径弯管制造装备现状,技术标准及陕京输气管道工程弯管制造国产化的经验,论证了大口径弯管制造国产化的可能性,并提出了大口径弯管国产化的工作方法和步骤。  相似文献   
84.
邓敬  刘康 《时代建筑》2013,(4):92-97
德阳市特殊教育学校的设计以"家"的概念作为创作起点,建筑从儿童画里提取基本形态,形成纯粹几何体的组群聚落。文章在隐喻和戏剧性手法的叙事逻辑关联基础上,对设计作品中的原型提取、聚落层级关系、空间与界面操作等方面进行了深入分析。  相似文献   
85.
This paper describes a concept for a product called the Personal Action Wireless Sensor (PAWS), a system that estimates human action within a home environment. In this system, a watch-like motion sensor worn by user communicates wirelessly via a network of locator devices, which determine user location to a host computer. The host software combines the inputs of motion, angular position, location, and time to recognize user action.  相似文献   
86.
徐大庆 《无线通信技术》2004,13(3):26-28,37
未来移动通信将包含多种不同的无线网络存取技术与标准 ,移动终端如何运转在不同的无线网络系统下 ,如何使用不同的无线存取技术 ( UMTS,cdma2 0 0 0 ,GSM/GPRS,WLAN,WPAN等 ) ,这是本篇要考虑的问题。并提出了一个结构独立开放并有 Qo S保证的基于 All- IP的异构无线网漫游方案  相似文献   
87.
对目前房地产市场上常见的“电梯直接入户”户型,提出电梯应急救援时碰到的问题.给出问题的解决方法及对未来该类户型设计的建议。  相似文献   
88.
The meaning of migrant housing materiality has not been adequately researched, especially when compared to the meaning of the home for immigrants, a matter of extensive discussion in the past two decades. This paper focuses on the meaning of housing materiality for 12 immigrants who migrated from Morocco to Israel some 60?years ago. Drawing on qualitative data gathered in 2007 and 2008, the paper develops a theoretical framework considering “house as community” and “house materiality” as two interrelating explanations for the migrant housing materiality. Through this framework, and with the concepts of performance and performativity, the paper first explores former houses of participants in Morocco and then presents current houses in Tel Aviv, Israel, to establish links between the two housing forms and reveal the meanings of objects in the homes. It is argued that as a reaction to the dominant Israeli society, housing materiality enables participants to educate successive generations and Israeli society at large about the rich cultural life of Moroccan-Jews that existed before their migration to Israel.  相似文献   
89.
Home ownership is often regarded as the preferred housing tenure; however, situations in parallel life-course careers might make moving to a rental home necessary or attractive to home owners. Retrospective data from the SHARELIFE survey were used to study the short- and long-term impact of situations and disruptions in the family and housing careers on leaving home ownership at middle (45–64) and older ages (65–80) in Denmark, Sweden and the Netherlands. We found that directly after separation and widowhood, the likelihood of leaving home ownership was the greatest. However, more than 10 years after separation and widowhood, individuals were still significantly more likely to leave ownership than those in their first marriage. Furthermore, late first childbirth and early first-time home ownership were associated with lower chances of leaving home ownership. We conclude that situations and changes in family and housing careers have both a short-term and a long-term impact on the likelihood of moving out of home ownership.  相似文献   
90.
Past research confirms that parents extend much effort to teach their young children about safety, but little is known about this process. The present study examined mothers’ use of teaching as a strategy to manage young children's risk of home injury and how this impacts children's hazard interactions. Mothers of three-year-olds completed an in-home room-by-room interview in which they identified injury hazards that concern them, reported on use of teaching to manage risk of injury from these hazards, rated children's understanding of these safety issues and compliance with behavioral guidelines regarding these safety issues, and reported on children's recent interactions with these hazards. They also completed questionnaire measures of how difficult the child is to manage and the child's typical level of risk taking. Results revealed that children's understanding of safety impacted both their compliance and hazard interactions, moderating the impact of risk taking on compliance and also the impact of children's difficult-to-manage score on hazard interactions. These findings demonstrate that teaching strategies need to effectively enhance children's understanding of the safety issue in order to reduce children's risk of hazard interactions.  相似文献   
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