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1.
High dynamic range imaging (HDRI) by bracketing of low dynamic range (LDR) images is demanding, as the sensor is deliberately operated at saturation. This exacerbates any crosstalk, interpixel capacitance, blooming and smear, all causing interpixel correlations (IC) and a deteriorated modulation transfer function (MTF). Established HDRI algorithms exclude saturated pixels, but generally overlook IC. This work presents a calibration method to estimate the affected region from saturated pixels for a color filter array (CFA) sensor, using the native CFA as a matched filter. The method minimizes color crosstalk given a set of candidates for proximity regions, and requires no special setup. Results are shown for a 21‐bit HDR output image with improved color fidelity and reduced noise. The calibration reduces IC in the LDR images and is performed only once for a given sensor. The improvement is applicable to any HDRI algorithm based on CFA image bracketing, irrespective of sensor technology. Generalizations to subsaturated and supersaturated pixels are described, facilitating a suggested irradiance‐exposure dependent point spread function charge repatriation strategy.  相似文献   
2.
Bone and muscle are highly synergistic tissues that communicate extensively via mechanotransduction and biochemical signaling. Osteogenesis imperfecta (OI) is a heritable connective tissue disorder of severe bone fragility and recently recognized skeletal muscle weakness. The presence of impaired bone and muscle in OI leads to a continuous cycle of altered muscle–bone crosstalk with weak muscles further compromising bone and vice versa. Currently, there is no cure for OI and understanding the pathogenesis of the skeletal muscle weakness in relation to the bone pathogenesis of OI in light of the critical role of muscle–bone crosstalk is essential to developing and identifying novel therapeutic targets and strategies for OI. This review will highlight how impaired skeletal muscle function contributes to the pathophysiology of OI and how this phenomenon further perpetuates bone fragility.  相似文献   
3.
针对全光纤电流互感器(FOCT)传感环不闭合易受相间磁场干扰的问题进行了研究,并提出了一种提高不闭合FOCT抗相间磁场干扰能力的新方法。建立了不闭合FOCT相间磁场干扰数学模型,通过理论研究和仿真分析得出传感环不闭合度、传感环半径、传感环缠绕匝数和相间距离是构成相间磁场干扰特性的主要因素,且总有两个最佳方位角,使得相间磁场不会干扰本相FOCT准确度。据此提出了一种最佳方位角优化方法,即通过将FOCT摆放到最佳方位角,来提高抗相间磁场干扰的能力。实验结果与理论分析相一致,并验证了所提方法的正确性。通过该方法,相间磁场干扰引起的误差由-0.27%下降到-0.02%,使不闭合FOCT满足0.2级要求。  相似文献   
4.
研制了双面硅条探测器。探测器灵敏面积为48mm×48mm,厚约300μm,结面和欧姆面的硅条互相垂直,均由相互平行、宽度相等的48条组成,每条宽0.9mm、间距0.1mm。对其电气特性(耗尽偏压、反向漏电流、条间电阻)和探测特性(上升时间、能量分辨、条间串扰)进行了测试。在偏压为-15V时,各条平均反向漏电流小于10nA。对于从结面入射的5.157 MeV的α粒子,前放信号上升时间约45ns,结面各条的能量分辨率约0.6%~0.7%,基本无条间串扰;欧姆面各条能量分辨率较差,存在条间串扰。  相似文献   
5.
We consider the quantum optical eight-port homodyne detection scheme in the case that each of the associated photon detectors is assigned with a different quantum efficiency. We give a mathematically rigorous and strictly quantum mechanical proof of the fact that the measured observable (positive operator measure) in the high-amplitude limit is a smearing of the covariant phase space observable related to the ideal measurement, that is, the measurement performed with fully efficient detectors. The result is proved for an arbitary parameter field. Furthermore, we investigate some properties of the measured observable. In particular, we show that detector inefficiencies do not affect the observable's ability to distinguish between different states.  相似文献   
6.
In continuous-variable quantum key distribution, detectors are necessarily coarse grained and of finite range. We analyze the impact of both features and demonstrate that while coarse graining adds a fixed error to the estimated excess noise, finite range degrades the estimation accuracy of both transmission and excess noise. Moreover, the inaccurate estimation due to finite range may results in secret key rate underestimation, even misjudgment of security. To compensate these consequences, tuning the modulation variance is a possible way.  相似文献   
7.
Historically, cell-signaling pathways have been studied as the compilation of isolated elements into a unique cascade that transmits extracellular stimuli to the tumor cell nucleus. Today, growing evidence supports the fact that intracellular drivers of tumor progression do not flow in a single linear pathway, but disseminate into multiple intracellular pathways. An improved understanding of the complexity of cancer depends on the elucidation of the underlying regulatory networks at the cellular and intercellular levels and in their temporal dimension. The high complexity of the intracellular cascades causes the complete inhibition of the growth of one tumor cell to be very unlikely, except in cases in which the so-called “oncogene addiction” is known to be a clear trigger for tumor catastrophe, such as in the case of gastrointestinal stromal tumors or chronic myeloid leukemia. In other words, the separation and isolation of the driver from the passengers is required to improve accuracy in cancer treatment. This review will summarize the signaling pathway crossroads that govern renal cell carcinoma proliferation and the emerging understanding of how these pathways facilitate tumor escape. We outline the available evidence supporting the putative links between different signaling pathways and how they may influence tumor proliferation, differentiation, apoptosis, angiogenesis, metabolism and invasiveness. The conclusion is that tumor cells may generate their own crossroads/crosstalk among signaling pathways, thereby reducing their dependence on stimulation of their physiologic pathways.  相似文献   
8.
高速电路中蛇形线可作为传统防护布线的替代方案,但其提出过程未曾考虑如何进行合理的设计。文中基于蛇形防护布线的外形特征影响耦合参数的原理,通过全波求解器建立蛇形防护布线模型,分析了其端接策略以及特征变化对应的远端串扰变化规律,得出了蛇形防护布线的合理设计方法。结果表明,短路策略作为最佳策略,且在信号边沿变化较快的情况下,应采用线宽小、高度高和长度短的蛇形线作为防护布线。  相似文献   
9.
In this paper, it presented a device intended to reproduce magnetic fields of differents shapes to help the test or calibration of current measuring instruments based on Ampere's Law (current transformers, current clamps, and Rogowsky probes). In particular, this device can reproduce the effect of uncentered currents without requiring any mechanical displacement of the conductor or the device under test during its operation. Any uncentered or distributed current is approximated by a linear combination of currents flowing along a specific set of conductors. First, the theoretical vectorial analysis is presented, and second, a specific arrangement of conductors is used to illustrate the method. A number of measurements have been taken to check the results. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
10.
随着工艺特征尺寸的不断缩小,芯片的信号完整性问题逐渐恶化。根据超深亚微米(ultra-deep submicron,UDSM)工艺特性,阐述了串扰噪声和同步开关噪声(Simultaneous Switch Noise,SSN)的产生机理以及对芯片信号完整性的影响,并且分析了走线密度、时钟频率和供电布局等与这2类噪声强度相关的主要因素,进而得出了在集成电路版图设计早期,有效预防和抑制信号完整性问题的一系列方法。  相似文献   
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