在真实室内环境中,用MICA2节点设计分析影响无线接收信号强度(radio signal strength,RSS)的实验,发现其影响因素不仅包括发送接收方(transmitter-receiver,T-R)之间的距离,且MICA2节点的工作频率和供电电池电压、发送接收方节点差异、...在真实室内环境中,用MICA2节点设计分析影响无线接收信号强度(radio signal strength,RSS)的实验,发现其影响因素不仅包括发送接收方(transmitter-receiver,T-R)之间的距离,且MICA2节点的工作频率和供电电池电压、发送接收方节点差异、天线角度和高度,以及环境中的时空因素和动态环境等都会影响无线接收信号强度.经分别测试这些因素,建议传统无线信号传播模型和信号校准算法应综合考虑各项影响因素.展开更多
Characterizing the thermal properties of MoS2 is important for the design of electronic devices based on this material. We used frequency domain thermoreflectance to study the cross-plane thermal transport in mechanic...Characterizing the thermal properties of MoS2 is important for the design of electronic devices based on this material. We used frequency domain thermoreflectance to study the cross-plane thermal transport in mechanically exfoliated MoS2 samples supported on SiO2 and muscovite mica substrates. The thickness of MoS2 ranged between one and five layers, and the MoS2 layers were sandwiched between a metal layer and the substrate. In the case of mica, heat transport into the substrate remained the same whether or not a monolayer of MoS2 was present, whereas, for SiO2, heat transport was reduced by surface roughness. We observed a significant improvement in heat transport across monolayer MoS2 as compared to few layer MoS2. For MoS2 on SiO2, the effective thermal interface conductance was improved by more than three times if a monolayer was used. For MoS2 on mica, the thermal interface conductance was approximately two times better for monolayer MoS2. This implies that monolayer MoS2 has superior thermal properties and can be used in electronic devices as an intermediate layer between two materials. Additionally, we also report on the measurement of anisotropic thermal conductivity in bulk MoS2 and mica.展开更多
基金National Natural Science Foundation of China(61170077,61202377)~~
文摘在真实室内环境中,用MICA2节点设计分析影响无线接收信号强度(radio signal strength,RSS)的实验,发现其影响因素不仅包括发送接收方(transmitter-receiver,T-R)之间的距离,且MICA2节点的工作频率和供电电池电压、发送接收方节点差异、天线角度和高度,以及环境中的时空因素和动态环境等都会影响无线接收信号强度.经分别测试这些因素,建议传统无线信号传播模型和信号校准算法应综合考虑各项影响因素.
文摘Characterizing the thermal properties of MoS2 is important for the design of electronic devices based on this material. We used frequency domain thermoreflectance to study the cross-plane thermal transport in mechanically exfoliated MoS2 samples supported on SiO2 and muscovite mica substrates. The thickness of MoS2 ranged between one and five layers, and the MoS2 layers were sandwiched between a metal layer and the substrate. In the case of mica, heat transport into the substrate remained the same whether or not a monolayer of MoS2 was present, whereas, for SiO2, heat transport was reduced by surface roughness. We observed a significant improvement in heat transport across monolayer MoS2 as compared to few layer MoS2. For MoS2 on SiO2, the effective thermal interface conductance was improved by more than three times if a monolayer was used. For MoS2 on mica, the thermal interface conductance was approximately two times better for monolayer MoS2. This implies that monolayer MoS2 has superior thermal properties and can be used in electronic devices as an intermediate layer between two materials. Additionally, we also report on the measurement of anisotropic thermal conductivity in bulk MoS2 and mica.
