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11.
从安全性、国家产业政策以及公安实战需求方面考虑,350兆警用集群系统由模拟向数字化过度是必然趋势。本文根据吉林省350兆无线通信系统的实际情况,因地制宜,在充分保护现有投资的条件下,探讨全省350兆集群系统的数字化过渡的可行性方案。 相似文献
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Dynamic output feedback control of saturated switched delay systems under the PDT switching 下载免费PDF全文
This paper is devoted to saturated control of switched delay systems. The main focus is to find a suitable switching law and saturated output feedback controllers such that the closed‐loop systems are asymptotically stable and have the disturbance tolerance/rejection capacity. A mixed slow/arbitrary switching approach, so‐called persistent dwell time (PDT) switching, is used to design the switching law. Compared with the slow switching, it is more general and leads to more flexibility in the process of constructing switching signals. More importantly, the proposed PDT is dependent on state delay, which includes the previous delay‐independent PDT. Next, time‐varying ellipsoids and a prescribe l2‐gain are introduced to characterize the disturbance tolerance and rejection capacities of systems, respectively. Based on the proposed results, the relation between delay‐dependent PDT and level of disturbance tolerance/rejection is shown. Finally, saturated controllers working in time‐varying hull controllable regions are designed. Thus, the considered problem is solved. An example is exploited to illustrate the effectiveness of the proposed results. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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基于RFID和GPRS技术的城市物流配送系统研究 总被引:3,自引:0,他引:3
传统的城市物流配送系统普遍采用的PDT(Portable Data Terminal)虽然携带方便,但是却存在读写距离短、范围小,需要手工更新物流信息等不足.分析了传统城市物流配送系统中存在的一些缺点,提出了一种基于RFID(Radio Frequency Identification)和GPRS技术的城市物流配送系统框架,实现了大范围物流信息的采集、存储以及自动实时传输.详细分析了各组成部分主要功能及各子系统的具体实现. 相似文献
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Sergey Tikhonov Natalia Morozova Anna Plutinskaya Ekaterina Plotnikova Andrey Pankratov Olga Abramova Ekaterina Diachkova Yuriy Vasilev Mikhail Grin 《International journal of molecular sciences》2022,23(24)
Photodynamic therapy (PDT) is currently regarded as a promising method for the treatment of oncological diseases. However, it involves a number of limitations related to the specific features of the method and the specific characteristics of photosensitizer molecules, including tumor hypoxia, small depth of light penetration into the tumor tissue, and low accumulation sensitivity. These drawbacks can be overcome by combining PDT with other treatment methods, for example, chemotherapy. In this work, we were the first to obtain agents that contain bacteriopurpurinimide as a photodynamic subunit and complexes of gold(I) that implement the chemotherapy effect. To bind the latter agents, N-heterocyclic carbenes (NHC) based on histidine and histamine were obtained. We considered alternative techniques for synthesizing the target conjugates and selected an optimal one that enabled the production of preparative amounts for biological assays. In vitro studies showed that all the compounds obtained exhibited high photoinduced activity. The C-donor Au(I) complexes exhibited the maximum specific activity at longer incubation times compared to the other derivatives, both under exposure to light and without irradiation. In in vivo studies, the presence of histamine in the NHC-derivative of dipropoxy-BPI (7b) had no significant effect on its antitumor action, whereas the Au(I) metal complex of histamine NHC-derivative with BPI (8b) resulted in enhanced antitumor activity and in an increased number of remissions after photodynamic treatment. 相似文献
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旋转导向钻井系统控制井眼轨迹机理研究 总被引:3,自引:5,他引:3
分析了井眼轨迹的旋转导向机理及井眼轨迹旋转导向偏差矢量控制方法的原理,同时还对常规井眼轨迹控制方法与偏差矢量控制方法进行了比较。 相似文献
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Under water-rich conditions, small amphiphilic and hydrophobic drug molecules self-assemble into supramolecular nanostructures. Thus, substantial modifications in their interaction with cellular structures and the ability to reach intracellular targets could happen. Additionally, drug aggregates could be more toxic than the non-aggregated counterparts, or vice versa. Moreover, since self-aggregation reduces the number of effective “monomeric” molecules that interact with the target, the drug potency could be underestimated. In other cases, the activity could be ascribed to the non-aggregated molecule while it stems from its aggregates. Thus, drug self-assembly could mislead from drug throughput screening assays to advanced preclinical and clinical trials. Finally, aggregates could serve as crystallization nuclei. The impact that this phenomenon has on the biological performance of active compounds, the inconsistent and often controversial nature of the published data and the need for recommendations/guidelines as preamble of more harmonized research protocols to characterize drug self-aggregation were main motivations for this review. First, the key molecular and environmental parameters governing drug self-aggregation, the main drug families for which this phenomenon and the methods used for its characterization are described. Then, promising nanotechnology platforms investigated to prevent/control it towards a more efficient drug development process are briefly discussed. 相似文献
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Catharina M. Lerche Ida M. Heerfordt Jakob Heydenreich Hans Christian Wulf 《International journal of molecular sciences》2016,17(3)
Daylight-mediated photodynamic therapy (daylight PDT) is a simple and pain free treatment of actinic keratoses. Weather conditions may not always allow daylight PDT outdoors. We compared the spectrum of five different lamp candidates for indoor “daylight PDT” and investigated their ability to photobleach protoporphyrin IX (PpIX). Furthermore, we measured the amount of PpIX activating daylight available in a glass greenhouse, which can be an alternative when it is uncomfortable for patients to be outdoors. The lamps investigated were: halogen lamps (overhead and slide projector), white light-emitting diode (LED) lamp, red LED panel and lamps used for conventional PDT. Four of the five light sources were able to photobleach PpIX completely. For halogen light and the red LED lamp, 5000 lux could photobleach PpIX whereas 12,000 lux were needed for the white LED lamp. Furthermore, the greenhouse was suitable for daylight PDT since the effect of solar light is lowered only by 25%. In conclusion, we found four of the five light sources and the greenhouse usable for indoor daylight PDT. The greenhouse is beneficial when the weather outside is rainy or windy. Only insignificant ultraviolet B radiation (UVB) radiation passes through the greenhouse glass, so sun protection is not needed. 相似文献
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Jingyuan Li Dadong Guo Xuemei Wang Huangping Wang Hui Jiang Baoan Chen 《Nanoscale research letters》2010,5(6):1063-1071
Nanomaterials have widely been used in the field of biological and biomedicine, such as tissue imaging, diagnosis and cancer therapy. In this study, we explored the cytotoxicity and photodynamic effect of different-sized ZnO nanoparticles to target cells. Our observations demonstrated that ZnO nanoparticles exerted dose-dependent and time-dependent cytotoxicity for cancer cells like hepatocellular carcinoma SMMC-7721 cells in vitro. Meanwhile, it was observed that UV irradiation could enhance the suppression ability of ZnO nanoparticles on cancer cells proliferation, and these effects were in the size-dependent manner. Furthermore, when ZnO nanoparticles combined with daunorubicin, the related cytotoxicity of anticancer agents on cancer cells was evidently enhanced, suggesting that ZnO nanoparticles could play an important role in drug delivery. This may offer the possibility of the great potential and promising applications of the ZnO nanoparticles in clinical and biomedical areas like photodynamic cancer therapy and others. 相似文献