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21.
The proliferation of applied behaviour change science over the past decade has provided new ways of thinking about policy making. Policy makers now have a range of frameworks and methods to assist in formulating change for social and environmental benefits. However, the development of strategies for the identification and prioritisation of target behaviours has been less forthcoming. This paper outlines a tool to assist in behaviour selection. Behaviours are assessed for their potential impact on addressing a specific issue, the likelihood of adoption by the target audience and existing participation levels within the target audience. Each of these characteristics is scored, allowing behaviours to be mapped onto a meaningful, visual, matrix for prioritisation. Additional data on behaviour type and the key perceived barriers to participation in each behaviour are layered onto the matrix to provide direction for intervention design. An application of the prioritisation matrix is presented within an environmental context through a case study of water demand management behaviours for domestic consumers in Australia. The prioritisation matrix could provide a decision-making tool for policy makers to assist in the selection of target behaviours to address complex issues. 相似文献
22.
目的研究在机体两侧螺旋桨声波干涉状态下,机体假件表面的降噪效果。方法通过模拟双螺旋浆在机体两侧的分布结构,以壳体结构模拟机身壁板,两侧对称布置电机驱动的螺旋桨旋转台,搭建双桨干涉试验平台,控制螺旋桨运行状态,测量机身表面声压级分布,得到螺旋桨旋转平面内机身外表面的声压级分布规律。通过对比单桨运行状态与双桨干涉状态测点的声压级,验证双桨干涉对机体的降噪效果。结果双桨干涉具有明显的降噪效果,尤其是机体45°方向测点降噪效果最明显。与单桨运行状态相比,双桨对消状态下,最大降噪量为1.84 dB,靠近螺旋桨旋转中心测点(0°测点)声压级降低1.58 dB,机体最上方测点(90°)噪声略有上升,声压级增加0.29dB。结论双桨同时运行状态下,降低了机体表面一定区域的声压级,且对其余区域声压级增加较小,通过控制双桨运行状态能达到降噪的目的。 相似文献
23.
小波变换常用于数字信号传输的噪声检测与处理,为了检测煤矿生产系统中的突发事件,将其模拟为数字信号传输中的干扰,构建系统稳态方程和对应的扰动方程,根据离散小波变换原理,将煤矿生产系统中的监测数据分解为近似部分和细节部分,再进行离散变换。采用多尺度边缘检测法,由光滑后的一阶和二阶导数检测出信号的模极大值点即为瞬态突变点。将A矿记录到的瓦斯浓度监控数据进行可行性分析后,在MATLAB的wavelet工具中对该瓦斯浓度监控数据作离散小波变换,找到四个瓦斯浓度瞬态突变点,那么这四个时刻发生了煤与瓦斯突出事件。结果表明该方法简单、实用性强。据此从计算机实时监控和现场技术防突方面提出应对煤矿干扰事件的措施。 相似文献
24.
25.
We studied the impact of group size on foraging behaviour and level of movement synchronisation among female herdmates of a fallow deer population in Central Italy. Both proportion of foraging events and movement synchronisation decreased with increasing group size. The proportion of foraging events was higher for animals on the edge of the group than for deer in the centre of the group; hence, there appears to be a trade-off between protection against predators and foraging interference, both of which decrease from the centre to the periphery of the group. This is the first time this type of behaviour has been recorded for wild ungulates. As expected, we also found that the movement of peripheral animals was less synchronised than that of central animals. Consequently, peripheral animals may lose contact with their herdmates and split off the group. We conclude that social inequalities may lead to conflicting requirements among group members and instability of large groups. Movement synchronisation (as a function of group size) appears to interact with habitat openness to produce variations of group size (which appear to be adaptive for individuals) as an emergent property of these aggregations. 相似文献
26.
杉木-观光木人工混交林竞争及邻体干扰指数研究 总被引:1,自引:0,他引:1
将杉木和观光木人工混交林中林木竞争影响空间划分为内、外两圈,在此基础上将竞争指数分解为不同的邻体干扰指数,对象木生长量与3种干扰指数的回归分析表明,以杉木为对象木时,利用张大勇提出的干扰指数模型(Izdy)效果最好;以观光木为对象木时,利用Weiner提出的干扰指数模型(Iwg)效果最好.同时,竞争强度研究表明,杉木种内竞争>杉木观光种间竞争>观光木种内竞争.通过对几种竞争影响的划分比较,说明将竞争空间分为内、外两圈能较好地反应林木的竞争规律.表3参17 相似文献
27.
28.
The method for detecting N-nitrosodimethylamine (NDMA) in drinking water using ultra performance liquid chromatography
(UPLC) coupled with tandem mass spectrometry (MS/MS) was improved by optimizing the clean-up procedure to remove the matrix
interference in pretreatment process, and was then applied to a survey of NDMA in both raw and finished water samples from five
water treatment plants in South China. The NDMA concentrations ranged from 4.7 to 15.1 ng/L in raw water samples, and from 4.68
to 46.9 ng/L in finished water. The NDMA concentration in raw water was found to be related with nitrite concentration, and during
the treatment, the NDMA concentration increased following ozonation but decreased after subsequent activated carbon treatment. 相似文献
29.
为研究杂散电流干扰影响范围及严重程度,通过现场测试典型深井和浅埋阳极地床地表电位梯度,探讨地表电位梯度分布规律,分析阳极地床杂散电流干扰特性。结果表明:深井阳极地床地表电位梯度沿阳极井中心辐射线方向先增大后减小,浅埋阳极地床地表电位梯度沿垂直于阳极体方向呈递减趋势;浅埋阳极地床地表电位梯度峰值和衰减速率均大于深井阳极,但强干扰平均影响半径仅为深井阳极的1/2;从强干扰影响半径看,应优先选用浅埋阳极地床;可通过适当增加井深、对干扰区内金属构筑物排流等方式,缓解深井阳极地床杂散电流干扰影响。研究结果可为强制电流阴极保护阳极地床选型和选址提供理论指导。 相似文献
30.
The explosion characteristic parameters of polyethylene dust were systematically investigated. The variations in the maximum explosion pressure (Pmax), explosion index (Kst), minimum ignition energy (MIE), minimum ignition temperature (MIT), and minimum explosion concentration (MEC) of dust samples with different particle sizes were obtained. Using experimental data, a two-dimensional matrix analysis method was applied to classify the dust explosion severity based on Pmax and Kst. Then, a three-dimensional matrix was used to categorize the dust explosion sensitivity based on three factors: MIE, MIT, and MEC. Finally, a two-dimensional matrix model of dust explosion risk assessment was established considering the severity and sensitivity. The model was used to evaluate the explosion risk of polyethylene dust samples with different particle sizes. It was found that the risk level of dust explosion increased with decreasing particle size, which was consistent with the actual results. The risk assessment method can provide a scientific basis for dust explosion prevention in the production of polyethylene. 相似文献