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The performance of a time hopping combined with pulse position modulation ultra wide band system with a nonlinear receiver using an adaptive filter and a soft-limiter in the presence of narrowband interference has been considered. This system brings a significant performance improvement compared with the system that uses an adaptive filter and a linear receiver, particularly in the case of high-interference power where its absence leads to the reception loss. Also, the proposed receiver has much better interference rejection performance compared with minimal mean-square error interference rejection, in case of high-interference power (interference to signal ratios from 30 to 65 dB).  相似文献   
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OBJECTIVE: To examine operator strategies for diagnosing and recovering from errors and disturbances as well as the impact of automation design and time pressure on these processes. BACKGROUND: Considerable efforts have been directed at error prevention through training and design. However, because errors cannot be eliminated completely, their detection, diagnosis, and recovery must also be supported. Research has focused almost exclusively on error detection. Little is known about error diagnosis and recovery, especially in the context of event-driven tasks and domains. METHOD: With a confederate pilot, 12 airline pilots flew a 1-hr simulator scenario that involved three challenging automation-related tasks and events that were likely to produce erroneous actions or assessments. Behavioral data were compared with a canonical path to examine pilots' error and disturbance management strategies. Debriefings were conducted to probe pilots' system knowledge. RESULTS: Pilots seldom followed the canonical path to cope with the scenario events. Detection of a disturbance was often delayed. Diagnostic episodes were rare because of pilots' knowledge gaps and time criticality. In many cases, generic inefficient recovery strategies were observed, and pilots relied on high levels of automation to manage the consequences of an error. CONCLUSION: Our findings describe and explain the nature and shortcomings of pilots' error management activities. They highlight the need for improved automation training and design to achieve more timely detection, accurate explanation, and effective recovery from errors and disturbances. APPLICATION: Our findings can inform the design of tools and techniques that support disturbance management in various complex, event-driven environments.  相似文献   
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Magnetic behavior of C60 thin films in the Earth's magnetic field under polarization light influence is presented. Transformation of magnetic field for two fullerene thin films of different thickness is investigated. Two proton magnetometers were used for these measurements. Samples of 30 nm and 250 nm thickness illustrate a significant change of magnetic field intensity under the influence of polarization light, in range from 3.4 to 12.9 nT, for 200 measurement data per sample.  相似文献   
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Synthesis and characterization of copolymer obtained by grafting acrylamide onto hydrolyzed potato starch and its application in cotton yarn sizing were presented in this work. Some process parameters of starch hydrolysis and grafting, like as hydrolysis yield, grafting yield, grafting percentage, graft efficiency, and monomer to polymer conversion were determinated. Molar mass values of hydrolyzed starch and copolymer samples are located in a narrow range of 1 × 105 to 1 × 107 and 1 × 102 to 1 × 104. Grafted hydrolyzed starch, as a sizing agent, gives better results than nongrafted, particularly in terms of sizing uniformity, yarn mechanical parameters, and easier removal in subsequent desizing process.  相似文献   
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Alterations in mitochondrial function are an important control variable in the progression of metabolic dysfunction-associated fatty liver disease (MAFLD), while also noted by increased de novo lipogenesis (DNL) and hepatic insulin resistance. We hypothesized that the organization and function of a mitochondrial electron transport chain (ETC) in this pathologic condition is a consequence of shifted substrate availability. We addressed this question using a transgenic mouse model with increased hepatic insulin resistance and DNL due to constitutively active human SREBP-1c. The abundance of ETC complex subunits and components of key metabolic pathways are regulated in the liver of these animals. Further omics approaches combined with functional assays in isolated liver mitochondria and primary hepatocytes revealed that the SREBP-1c-forced fatty liver induced a substrate limitation for oxidative phosphorylation, inducing enhanced complex II activity. The observed increased expression of mitochondrial genes may have indicated a counteraction. In conclusion, a shift of available substrates directed toward activated DNL results in increased electron flows, mainly through complex II, to compensate for the increased energy demand of the cell. The reorganization of key compounds in energy metabolism observed in the SREBP-1c animal model might explain the initial increase in mitochondrial function observed in the early stages of human MAFLD.  相似文献   
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