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101.
In order to improve the organizing performance and fault tolerance of the wireless network protocol GEAR based on the geographical location information in the Internet of things and achieve better energy distribution and conservation effects. This paper proposes a new multipath routing organizing protocol (SMG, Self-organized Multipath GEAR) based on the basic geographic routing protocol GEAR. By two-step organizing, communication empty nodes and communication hole can join the network respectively and energy spreading out and mechanism of dormancy of the multi-path are utilized to spread out and save energy. Meanwhile, this paper presents an approximate estimation algorithm to estimate the number of the nodes in the monitoring region with a certain size and regular shape. The critical path node goes to failure in different times while received packet rate is monitored using the experiment of NS2 simulation and actual hardware. The experiment results show that the improved protocol increases the fault tolerance of the network, reduces the paralysis rate of the network and achieves the effect of energy spreading out and saving, increases the lifetime of the network through a multi-path strategy. 相似文献
102.
Duo Wang Xiaoqi Zhu Xiaobo Wang Qin Wang Kangning Yan Guichun Zeng Guanhua Qiu Rong Jiao Xia Lin Jie Chen Qiaoling Yang Wen Qin Junjie Liu Kun Zhang Yan Liu 《Advanced functional materials》2023,33(48):2303869
Tumor adaptation-originated tumor tolerance that compensatory mechanisms (e.g., isocitrate dehydrogenase (IDH) mutation) jointly shape is the dominant obstacle of ROS therapy. Currently, targeting a single pathway fails to fundamentally reverse the complex milieu and diminish tumor adaptation. Herein, a multichannel sonocatalysis amplifier is engineered via one-pot gas diffusion method to attenuate IDH1-mutated cholangiocarcinoma plasticity and tolerance to ROS therapy, wherein triptolide and IR780 are co-loaded in DSPE-mPEG-modified CaCO3 nanoparticles. Triptolide can blockade Nrf2 to cut off glutathione biosynthesis via blockading proteomic communication, and disrupt redox homeostasis to potentiate IR780-mediated sonocatalytic ROS production. ROS-induced mitochondria damages disrupt Ca2+ homeostasis and in turn aggravate ROS accumulation, which cooperates with sonocatalysis and Nrf2 blockade to reprogram mitochondrial energy and substance metabolism (e.g., adenosine triphosphatase and glutathione), hinder DNA self-repair, and impair IDH1-mutation-asired tolerance. Systematic experiments support that these actions in such multichannel sonocatalysis amplifiers indeed disrupt Ca2+/redox homeostasis to disarm robust tumor plasticity and IDH1-mutation-induced tolerance to sonocatalysis therapy against IDH1-mutated cholangiocarcinoma progression. Briefly, the sonocatalysis amplifiers pave a comprehensive avenue to reprogram tumor metabolism, target tumor vulnerability, and attenuate tumor plasticity against genomic instability-raised treatment adaptation. 相似文献
103.
Dachuan Jiang Shiqiang Ren Shuang Shi Wei Dong Jieshan Qiu Yi TAN Jiayan Li 《Journal of Electronic Materials》2014,43(2):314-319
Silicon is widely used as a raw material for production of solar cells. As a major impurity in silicon, phosphorus must be removed to 1 × 10?5 wt.%. In the present study, based on the distribution of phosphorus in a silicon ingot obtained by vacuum refining and directional solidification, the mechanism for removal of phosphorus from silicon is investigated. The results show that the distribution is controlled not only by segregation at the solid–liquid interface but also by evaporation at the gas–liquid interface, showing some deviation from Scheil’s equation. A modified model which considers both segregation and evaporation is used to simulate the distribution, matching quite well with the experimental results. The temperature and solidification rate are two important parameters that affect the overall mass transfer coefficient and the effective segregation coefficient and thus the distribution of phosphorus. A high removal efficiency and a homogeneous distribution can be obtained by adjusting these two parameters. 相似文献
104.
Nonlinear simulations demonstrate the possibility for a coaxial-waveguide cyclotron autoresonance maser (CARM) amplifier to operate at a frequency of 140?GHz emitting hundreds of watts with an ultrahigh gain of 68?dB. Careful design of the operating magnetic field is of importance to the power of the device, although the other initial parameters such as electron-beam radius and voltage also affect the power. Like a cylindrical-waveguide CARM, a coaxial-waveguide CARM amplifier is sensitive to the velocity spread of the electron beam. 相似文献
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虚拟专用网与Internet的结合形成了当前业界发展的一个热点-INPV。IVPN通过加密、鉴定和隧道协议来实现,它把路由器交换机和传输线结合在一起,以实现安全保密的通信。IETF的IPsec是隧道协议的一种,为VPN之间的互操作提供了标准,目前已有一些IPS提供了具有一定安全性的IVPN业务。 相似文献
110.
为了提供更好的基于流的计费和策略控制,3GPP在IMSR7版本中提出策略与计费控制体系架构,其基本思路是将IMSR6版本中的策略决策功能实体和计费策略功能实体合并为R7中的策略与计费规则功能实体。本文首先简要介绍了IMSR6和IMSR7控制模型;然后重点分析了与策略控制、计费控制相关Gx接口、Rx接口的接口消息及其参数。分析表明,通过定义特定AVP,实现了IMSR6向IMSR7策略控制和计费控制接口的平滑演进。 相似文献