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51.
Home‐range estimates are an important input to species recovery plans. Our aim was to estimate the home‐range size of the endangered Macquarie Perch in the lower Cotter River catchment, Australia. In total, fourteen home‐range estimates were calculated from intensive radio‐tracking of adult individuals over a minimum of five diel periods in either autumn (n = 5) or spring (n = 9). Home‐range (95% Kernel) and core area (50% Kernel) were calculated by Kernel estimation and corrected for overlap with land. Seasonal estimates of home‐range and core area were not asymptotic in relation to cumulative number of radio‐fixes in four of fourteen cases. The mean within‐season home‐range of adult Macquarie perch was 5.5 ha ranging from 0.2 to 18.4 ha, based on 10 cumulative estimates that were asymptotic in relation to radio‐tracking effort. All five individuals radio‐tracked in autumn occupied a single core area, whereas in spring, six individuals occupied a single core area and three individuals each occupied three core areas. Despite individuals moving on a scale almost comparable to Cotter Reservoir (48.5 ha), only a single radio‐tagged individual was found to leave the reservoir and enter the river. Regional fisheries managers are generally aware of the requirement for Macquarie perch to access flowing water for spawning in south‐eastern Australia; however, in the Cotter River catchment, the protection of habitat for this species within Cotter Reservoir is also paramount. Our study highlights the importance of reservoirs for conserving a threatened aquatic species.  相似文献   
52.
基于DBF技术的星载SAR宽测绘带实现方法   总被引:1,自引:0,他引:1  
在研究距离向使用数字波束形成(Digital Beanforming,DBF)实现星载SAR宽测绘带原理的基础上,分析了星载DBF-SAR距离模糊与传统星载SAR距离模糊的不同,并利用阵列天线零点指向技术实现宽零陷的原理,展宽模糊点所对应位置零陷宽度,从而在提高星载SAR宽测绘带基础上有效地减小距离模糊,提高成像质量.通过仿真和比较分析,表明使用具有宽零陷指向特性的DBF技术实现星载SAR宽测绘带模式的可行性.  相似文献   
53.
针对移动机器人的测距系统,采用了红外线传感器与超声波传感器共同测距,避免了因使用单个传感器进行多次测量而降低系统的实时性和产生信号串扰问题;应用自适应加权数据融合估计算法对实时测量数据进行在线融合估计,只对当前采样时刻的测量数据进行自适应加权融合,而各传感器的加权因子则通过传感器的测量数据进行方差在线学习估计以自适应方式进行调整,使融合结果的均方误差始终最小,实现两种传感器在功能上的互补;实验结果表明,该方法提高了整体测距精度,得到了被测距离更加准确的估计.  相似文献   
54.
Abstract— A new digital ambient‐light sensor system is presented which employs two linear light sensors with different sensitivities and automatically adjusts the sensitivity based on the illumination condition. The adaptation mechanism allows a very wide range of light intensity to be detected, and the input dynamic range of the system is substantially improved from 22.5 to 45.1 dB. The proposed method does not require any additional precision bits for output data. Due to the small number of the output bits and the simple conversion process, the system can be easily integrated on the display panel.  相似文献   
55.
基于数据挖掘的肝阳上亢证的症状敏感性研究   总被引:1,自引:0,他引:1       下载免费PDF全文
应用偏微分效用分析方法对中医肝阳上亢证的症状敏感性进行了研究,绘制出了程度影响参考曲线。在此基础上,又对研究对象进行了深度挖掘分析,得出了在限定性条件下症状对肝阳上亢证影响敏感性的一般性结论。提出了诊断-治疗参考模型的设想。  相似文献   
56.
本文提出“针对式坦克发展战略”主要内容,它要求“突破性新概念高新技术”,获得“减法设计方法”,因而形成“坦克发展新道路”.运用“系统总体取胜”的系统工程理论,处理好坦克全系统“综合”、全系统与分系统“配置”、分系统与分系统“匹配”、全系统与人及作战环境“适应”四大关系,以“相互同水平组合”替代“单项高水平爬坡”.通过“从系统总体着眼、由边际零部件突破”的途径,善于从各个部分或部件之间的结合部加以突破,实现坦克设计新发展.  相似文献   
57.
Ghosting artifacts due to misaligned imaging and missing content of the moving regions are major challenges of synthesizing high dynamic range (HDR) images from multiple low-dynamic range (LDR) with different exposures in dynamic scenes. Therefore, it hopes the HDR reconstruction model can align the LDRs’ features and restore the missing content without artifacts. In the paper, a new dual-branch recursive band reconstruction network for high dynamic range (DRBR-HDR) is proposed to generate credible result in missing content regions, which not only uses global features as supplementary information to help local features from different receptive fields for efficient feature alignment but also designs a series of coarse-to-fine band representation to better repair missing areas in the process of recursion. In addition, we introduce an interactive attention mechanism for local branches to alleviate ghosting artifacts. The experimental results demonstrate that DRBR-HDR achieves state-of-the-art performance compared with that of the prevailing HDR reconstruction methods in various challenging scenes.Index Terms—inverse tone mapping, band reconstruction, global features, high dynamic range images.  相似文献   
58.
崔岩 《半导体光电》2022,43(5):974-978
传统的星载变频通道存在易受电磁干扰、动态范围受限、带宽瓶颈等不足,将微波光子技术引入卫星通信系统中,可克服电域信号变频的局限性,提升星载变频通道的性能。文章提出了一种基于并联马赫-增德尔调制器(MZM)与相干接收的宽带微波光子变频技术,通过采用相干接收方法,能够实现较好的共模噪声抑制,并降低谐波失真的影响,同时结合抑制载波调制方式所带来的优势,有效改善了变频无杂散动态范围等指标。通过实验验证,其杂散抑制比优于60 dB,无杂散动态范围优于100 dB·Hz2/3,为新型星载微波光子变频方案设计、实际应用提供了必要的理论依据与技术支撑。  相似文献   
59.
Heterogeneous Networks (HetNets) and cell densification represent promising solutions for the surging data traffic demand in wireless networks. In dense HetNets, user traffic is steered toward the Low-Power Node (LPN) when possible to enhance the user throughput and system capacity by increasing the area spectral efficiency. However, because of the transmit power differences in different tiers of HetNets and irregular service demand, a load imbalance typically exists among different serving nodes. To offload more traffic to LPNs and coordinate the Inter-Cell Interference (ICI), Third-Generation Partnership Project (3GPP) has facilitated the development of the Cell Range Expansion (CRE), enhanced Inter-Cell Interference Coordination (eICIC) and Further enhanced ICIC (FeICIC). In this paper, we develop a cell clustering-based load-aware offsetting and an adaptive Low-Power Subframe (LPS) approach. Our solution allows the separation of User Association (UA) functions at the User Equipment (UE) and network server such that users can make a simple cell-selection decision similar to that in the maximum Received Signal Strength (max-RSS) based UA scheme, where the network server computes the load-aware offsetting and required LPS periods based on the load conditions of the system. The proposed solution is evaluated using system-level simulations wherein the results correspond to performance changes in different service regions. Results show that our method effectively solves the offloading and interference coordination problems in dense HetNets.  相似文献   
60.
Reference range is a statistic that is used in health related fields to represent the range of the most likely values for a variable of interest. Based on this range, individuals are classified as being healthy or unhealthy. In biostatistics, the reference range is calculated as the (1 ? α)% prediction interval, where this prediction interval is based on the estimated population variance from the data. Such estimation of population variance is not precise, because obtained test results do usually have errors associated with them. These errors are due to the imprecise test procedure or gauge used. In this paper, the total variability in the data is decomposed into two categories. The first is the patient‐to‐patient variability and the other is the variability due to the measurement system used. Estimation of the two kinds is performed through a gauge repeatability and reproducibility study, then the reference range is calculated, taking into account only the patient‐to‐patient variability. The revised reference range procedure is illustrated through a case study of vitamin B12 test results. A closed form formula is given to calculate the probability of a given test result being within the revised reference range. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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