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121.
宽波段DMD动态红外景象仿真器投影光学系统设计   总被引:2,自引:3,他引:2  
宽波段红外景象仿真器可用于内场评价和验证中波/长波红外双波段成像仪。详细介绍了基于数字微镜器件(DMD)的动态红外景象仿真器的组成和工作原理。重点介绍了覆盖中波和长波红外的宽波段红外投影光学系统的指标要求、设计思想和设计结果。基于离轴三反射镜系统设计的系统,具有无色差、适用波段宽、相对孔径大、结构较紧凑、成像质量好等优点。根据待测设备要求,设计了一款口径100、相对孔径F/2.84、全面视场角4.4°、成像质量接近于衍射极限的宽波段投影光学系统。  相似文献   
122.
Organic-inorganic hybrid film using conjugated materials and quantum dots (QDs) are of great interest for solution-processed optoelectronic devices, including photovoltaics (PVs). However, it is still challenging to fabricate conductive hybrid films to maximize their PV performance. Herein, for the first time, superior PV performance of hybrid solar cells consisting of CsPbI3 perovskite QDs and Y6 series non-fullerene molecules is demonstrated and further highlights their importance on hybrid device design. In specific, a hybrid active layer is developed using CsPbI3 QDs and non-fullerene molecules, enabling a type-II energy alignment for efficient charge transfer and extraction. Additionally, the non-fullerene molecules can well passivate the QDs, reducing surface defects and energetic disorder. The champion CsPbI3 QD/Y6-F hybrid device has a record-high efficiency of 15.05% for QD/organic hybrid PV devices, paving a new way to construct solution-processable hybrid film for efficient optoelectronic devices.  相似文献   
123.
Sink scheduling, in the form of scheduling multiple sinks among the available sink sites to relieve the level of traffic burden, is shown to be a promising scheme in wireless sensor networks (WSNs). However, the problem of maximizing the network lifetime via sink scheduling remains quite a challenge since routing issues are tightly coupled. Previous approaches on this topic either suffer from poor performance due to a lack of joint considerations, or are based on relaxed constraints. Therefore, in this paper, we aim to fill in the research blanks. First, we develop a novel notation Placement Pattern (PP) to bound time-varying routes with the placement of sinks. This bounding technique transforms the problem from time domain into pattern domain, and thus, significantly decreases the problem complexity. Then, we formulate this optimization in a pattern-based way and create an efficient Column Generation (CG) based approach to solve it. Simulations not only demonstrate the efficiency of the proposed algorithm but also substantiate the importance of sink mobility for energy-constrained WSNs.  相似文献   
124.
PC机串行口扩展1-WIRE总线设备   总被引:1,自引:0,他引:1  
1-WIRE总线是利用一根数据线进行双向数据传输的通信协议。一般的设备或控制器都不带有1-WIRE接口,因此设计了一个接口电路,利用PC机串行口,以电平转换芯片MAX233A将232电平转换成TTL电平,连接RS232串行口与1-WIRE总线.并且采用直接从串口取电的方法为整个电路供电,以简化硬件电路;在软件上采用波形模拟的方法,即通过改变串行通信的波特率与数据位个数来输出不同宽度的脉冲,达到利用串行口输出与1-WIRE总线要求一致的操作时隙,驱动1-WIRE总线设备进行通信。最后编写了最基本的一些驱动程序。此设计为不同通信协议的转换提供了新的思路。  相似文献   
125.
综合孔径辐射计可见度函数预处理算法及时域仿真研究   总被引:2,自引:0,他引:2  
该文研究了干涉式综合孔径辐射计可见度函数的预处理算法,包括A/D偏置校正、三阶数字相关系数到模拟相关系数的校正、IQ非正交校正以及空间去相关的误差校正等等。由于这是首次将三阶量化数字相关的定标方法应用于对地观测领域,对其进行了详细的分析。该文利用蒙特卡洛方法对可见度函数的预处理算法进行了时域仿真的研究。并通过地球同步轨道毫米波大气温度探测仪地面样机系统对算法进行了验证,证明了该算法的正确性。经过可见度预处理算法校正得到的结果的绝对误差小于真值的0.1%。证明该算法可以应用于地球同步轨道毫米波大气温度探测仪星载系统定标中,经过校正得到的相关结果可以直接用于亮温图像的反演。  相似文献   
126.
随着不断深入的电力体制改革,电力市场化进程飞速发展,更多人开始关注如何才能更好更快地发展电力通信以及电力通信应该向着哪个方向发展。为此,文中首先分析了我国电力通信的现状,然后指出了我国电力通信中存在的问题,提出了发展的技术措施,而后对我国的发展战略进行了探讨,并在最后指出了我国电力通信市场开拓的策略。  相似文献   
127.
Pushing popular contents to the edge of the network can meet the growing demand for data traffic, reduce latency and relieve the pressure of the backhaul. However, considering the limited storage space of the base stations, it is impossible to cache all the contents, especially in ultra-dense network ( UDN). Furthermore, the uneven distribution of mobile users results in load imbalance among small base stations (SBSs) in both time and space, which also affects the caching strategy. To overcome these shortcoming, the impact of the changing load imbalance in UDN was investigated, and then a dynamic hierarchical collaborative caching (DHCC) scheme was proposed to optimize latency and caching hit rate. The storage of the SBS is logically divided into the independent caching layer and the collaborative caching layer. The independent caching layer caches the most popular contents for local users爷interest, and the collaborative caching layer caches contents as much as possible for the benefit of content diversity in the region. Different SBSs have respective storage space layer division ratios, according to their real-time traffic load. For SBSs with heavy load, the independent caching layers are allocated with more space. Otherwise, the collaborative caching layers could store more contents with larger space. The simulation results show that, DHCC improved both transmission latency and hit rate compared with existing caching schemes.  相似文献   
128.
In consideration of low cost, simple operation, safe reliability, and environmental benignity, aqueous rechargeable batteries (ARBs) have attracted great interest among portable electronic devices, energy storage, and power source batteries. As the key components of ARBs, the electrode materials lead to a crucial effect for the overall battery properties, such as working voltage, electrocatalytic activity, capacity, and cycling stability. However, owing to the highly reactive aqueous environment, the electrode materials typically demonstrate a series of issues, including active material dissolution, structural instability, and poor catalytic activity, restricting their application. So far, several researchers have devoted much effort to improve the properties of electrode materials for ARBs. In particular, intrinsic structure modification in terms of vacancy regulation, interlayer engineering, and element doping have been applied to optimize the electronic and phase structure of electrode materials, contributing to elevated ion diffusion, fast charge transfer, and adequate active sites for electrochemical reaction. In this review, recent reports are demonstrated about the intrinsic structure modification of electrode materials in aqueous metal-ion and metal-air batteries, focusing on various regulation strategies and functional mechanisms. Finally, a brief conclusion and perspective is presented to demonstrate constructive suggestions and opinions for further research.  相似文献   
129.
空心布拉格光纤在传感领域应用极为广泛。本文提出了一种基于带有缺陷层的太赫 兹(terahertz,THz)空心布拉格光纤的表面生物传感器,并对该传感器在太赫兹频段的细菌种类检测性能进行 分析。在太赫兹布拉格光纤中,高折射率光敏树脂层和低折射率空气层以纤芯为中心周期性 排列,在纤芯内壁沉积分析物引入缺陷模式。本文对提出的传感器性能进行了数值研究。仿 真结果表明,该传感器有很高的纤芯功率比,限制损耗在0.3 THz和0.45 TH z频 段有损耗峰,能得到可识别的特征频率,此特征频率用于细菌种类检测。当频率大于0.7 TH z时,该传感器可实现厚度无关的表面生物传感。本文所提出的基于太赫兹空心布拉格光纤 的 表面生物传感器可用于检测细菌种类,在微生物检测方面有很大的应用潜力。  相似文献   
130.
IP over elastic optical network is a very promising networking architecture to interconnect data centers. It can enable efficient resource utilization and support heterogeneous bandwidth demands in cost-effective, highly available, and energy-effective manner. In case of aggregation elastic optical network node failure, to ensure a high-level quality of service for user request after the failure becomes a research focus. In this paper, we present a novel multi-stratum resources resilience (MSRR) architecture for the data center services in software defined data center interconnection based on IP over elastic optical networks. The MSRR can enable joint optimization of IP network, elastic optical network, and application stratum resources, and enhance the service resilience and the data center responsiveness to the dynamic end-to-end service demands. Additionally, a service-aware resource collaborative resilience strategy for MSRR is introduced based on the proposed architecture, which can provide the restoration using the multiple stratums resources in case of failure. The overall feasibility and efficiency of the proposed architecture are experimentally verified on our testbed. Moreover, the network performances are quantitatively evaluated through the simulation under heavy traffic load scenario in terms of path blocking probability, resource occupation rate, and path resilience latency.  相似文献   
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