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1.
吴志忠  张兴周 《应用科技》2004,31(8):17-18,21
介绍了一种基于大规模CPLD实现的8路时分复用光纤传输系统的原理,并详细说明了利用编/解码芯片和大规模CPLD实现时分多路传输系统的方法,为了实现多路数字信号传输,系统采用了TDM和WDM技术,信道中两路光载波信号分别为850nm和1310nm.通过试验,验证了方案的可行性和先进性。  相似文献   
2.
Latamoxef, a broad‐spectrum anti‐bacterial agent of the β‐lactam antibiotics, is used off‐label in treatment of neonatal sepsis. Large inter‐individual variability and uncertainty of treatment make therapeutic drug monitoring (TDM) useful to optimize antimicrobial therapy. The objective of this study was to develop and validate a simple, selective and reliable HPLC method for the determination of latamoxef in small volumes of plasma, which could be used in neonatal TDM. After a simple protein precipitation, analytes were separated with liquid chromatography and quantified by UV detection, with tinidazole as the internal standard. The calibration range was linear from 3.0 to 60.0 μg/mL. Intra‐ and inter‐day precisions were < 7.2%. The acceptance criteria of accuracy (between 85 and 115%, 120% for lower limit of quantification) were met in all cases. A plasma volume of 50 μL was required to achieve the limit of quantification of 3.0 μg/mL. The TDM results showed a large variability in trough concentrations. A large number of patients were underdosed, highlighting the unmet need for TDM to optimize latamoxef therapy in neonates.  相似文献   
3.
多任务处理通常基于多任务操作系统,由多任务OS的核心系统调度器根据各个任务的优先级来调度CPU的控制权。但在多任务系统平台上进行产品开发,不仅成本高,而且开发周期长。以TXC设备为例,讲述了单任务平台上多任务处理的实现机制——基于优先级的调度算法。  相似文献   
4.
Mycophenolic acid (MPA) is an immunosuppressant drug which powerfully inhibits lymphocyte proliferation. Since the early 1990s it has been used to prevent rejection in organ transplantation. The requirement of therapeutic drug monitoring shown in previous studies raises the necessity of acquiring accurate and sensitive methods to measure MPA and its major metabolite mycophenolic acid glucuronide (MPAG).The authors developed a sample cleanup-free, rapid, and highly specific method for simultaneous measurement of MPA and MPAG in human plasma and serum using the novel technology of ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry. MPA- and MPAG-determinations were performed during a 2.0-min run time. Multiple calibration curves for the analysis of MPA and MPAG exhibited consistent linearity and reproducibility in the range of 0.05-100 (r > 0.999) mg L−1 and 4-4000 mg L−1 (r > 0.999), respectively. Limits of Detection were 0.014 mg L−1 for MPA and 1.85 mg L−1 for MPAG. Lower Limits of Quantification were 0.05 mg L−1 for MPA and 2.30 mg L−1 for MPAG. Interassay imprecision was <10% for both substances. Mean recovery was 103.6% (range 78.1-129.7%) for MPA and 111.1% (range 73.0-139.6%) for MPAG. Agreement was good for MPA and MPAG between the presented method and a validated HPLC-MS/MS method. The Passing-Bablok regression line for MPA and MPAG was HPLC-MS/MS = 1.14 UPLC-MS/MS—0.14 [mg L−1], r = 0.96, and HPLC-MS/MS = 0.77 UPLC-MS/MS + 0.50 [mg L−1], r = 0.97, respectively. This sample cleanup-free and robust LC-MS/MS assay facilitates the rapid, accurate and simultaneous determination of MPA and MPAG in human body fluids.  相似文献   
5.
王恒运  郝宝童  何巨 《应用光学》2003,24(5):28-31,35
在信息传输的各个领域中,光纤作为传输信号媒介的应用得以迅速发展。光纤的音频多路数字化传输也是光纤领域目前开发的热点课题之一,它充分利用光纤本身所具有的各种特点,使音频信号的传输更有效、更可靠。本文利用串行信号的时分复用技术,完成了多路音频数字化信号的光纤传输。提出信号传输中,数据信号和控制信号的复用及解复用解决方法。  相似文献   
6.
This article will discuss the importance of hybrid coexistence of sub-lambda grooming with wavelength-based services for driving down costs and maximizing the use of metro bandwidth, as well as enabling next-generation lambda-based services. The article will also address migration to all optical metro networks.  相似文献   
7.
This article will discuss the importance of hybrid coexistence of sub-lambda grooming with wavelength-based services for driving down costs and maximizing the use of metro bandwidth, as well as enabling next-generation lambda-based services. The article will also address migration to all optical metro networks.  相似文献   
8.
In this investigation, we experimentally investigate an extended reach (ER) time-division-multiplexed passive optical network (TDM-PON) using four wavelength-multiplexed channels to achieve 16 Gb/s downlink and 10 Gb/s uplink traffic. Each downlink signal uses the highly spectral efficient 4 Gb/s OFDM-QAM, and each uplink signal is generated by signal remodulating the downlink signal via a reflective semiconductor amplifier (RSOA) at 2.5 Gb/s non-return-to-zero (NRZ). In addition, the performance of the proposed ER TDM-PON has also been analyzed and discussed.  相似文献   
9.
In order to increase the availability of the part-time idle bus rapid transit lane (BRT-lane),a time divi-sion multiplexing (TDM) method to share BRT-lane with the vehicles besides BRT buses is propose...  相似文献   
10.
本文从设备图纸管理出发,着重介绍了基于TDM(Technology Data management)系统的设备图纸管理系统的特点、组成和有关技术创新点.给出了一个基于服务器-客户机的图纸技术数据提取和管理系统,使设备图纸管理从传统的索引管理迈入电子管理的方法.  相似文献   
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