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1.
动力环境集中监控系统的用户在使用过程中,往往结合自身需要提出一些特定的要求,但目前监控产品厂家所提供的软件却又不足以支持这些功能。文中结合实例,介绍了在Dreamweaver UltraDev开发环境下利用ASP技术,从动力监控系统的大型数据库中获取数据,自动生成报表的方法。这种方法无疑是一种有效、简洁的设计方法。实践证明该方法对于加强监控系统的例行维护管理具有重要的现实意义。  相似文献   
2.
Human biomonitoring is the assessment of actual internal contamination of chemicals by measuring exposure markers, chemicals or their metabolites, in human urine, blood, serum, and other body fluids. However, the metabolism of chemicals within an organism is extremely complex. Therefore, the identification of metabolites is often difficult and laborious. Several untargeted metabolomics methods have been developed to perform objective searching/filtering of accurate-mass-based LC-MS data to facilitate metabolite identification. In this study, three metabolomics data processing approaches were used for chemical exposure marker discovery in urine with an LTQ-Orbitrap high-resolution mass spectrometry (HRMS) dataset; di-isononyl phthalate (DINP) was used as an example. The data processing techniques included the SMAIT, mass defect filtering (MDF), and XCMS Online. Sixteen, 83, and 139 probable DINP metabolite signals were obtained using the SMAIT, MDF, and XCMS procedures, respectively. Fourteen probable metabolite signals mined simultaneously by the three metabolomics approaches were confirmed as DINP metabolites by structural information provided by LC-MS/MS. Among them, 13 probable metabolite signals were validated as exposure-related markers in a rat model. Six (m/z 319.155, 361.127, 373.126, 389.157, 437.112 and 443.130) of the 13 exposure-related DINP metabolite signals have not previously been reported in the literature. Our data indicate that SMAIT provided an efficient method to discover effectively and systematically urinary exposure markers of toxicant. The DINP metabolism information can provide valuable information for further investigations of DINP toxicity, toxicokinetics, exposure assessment, and human health effects.  相似文献   
3.
This paper details an investigation into the laser processing of medium-density fibreboard (MDF). Part 1 reports on the determination of process parameter settings for the effective cutting of MDF by CO2 laser, using an established experimental methodology developed to study the interrelationship between and effects of varying laser set-up parameters. Results are presented for both continuous wave (CW) and pulse mode (PM) cutting, and the associated cut quality effects have been commented on.  相似文献   
4.
MDF cements     
The applicability of MDF synthesis procedure, the coincidence of the interfacial cross-linking and the moisture resistance of MDF-related mixes based on two industrial Portland cements (CEM I, CEM II) and poly-P are reported. The knowledge of the moisture resistance of synthesized material is of paramount importance; two independent experimental methods confirmed that the moisture resistance of MDF cements based on CEM I (or CEM II) with 5% of poly-P achieves sufficient levels at 50% RH and at ambient values of RH. The results of thermal analysis are directly related to the former knowledge on the appearance and role of cross-links in the interfacial zone of MDF cements. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
5.
The system of sulfoaluminate ferrite belite (SAFB) clinkers premixed with Portland cement (PC) in mass ratio 85:15 in combination with hydroxypropylmethyl cellulose (HPMC) or polyphosphates(poly-P) was used for the syntheses of Macro-Defect-Free (MDF) materials. The subsequent moisture treatment and thermal stability of these MDF materials were investigated. The effect of individual humidity upon the evolution of mass is more intensive than the effects of composition of MDF materials or duration of the original MDF material synthesis. Detailed values of mass changes at 100% relative humidity (RH) and under ambient conditions are strongly affected by the nature of polymer used. A significant improvement of moisture resistance of MDF materials is achieved when the materials are dried after 24 h of finishing the pressure application. In the inter-phase section of MDF material samples, the content ofC-(A,F)-S hydraulic phases, mainly tetracalcium aluminate ferrite monosulphatehydrate (AFm) decomposing by 250°C and CaCO3 decomposing at 600–700°C increase after the moisture attack, while cross-links in AFm-like section with typical thermoanalytical traces in temperature region 250–550°C remain intact. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
6.
结合了ADSL和LAN两种典型接入方式 ,介绍宽带小区布线的基本原则和主要方法  相似文献   
7.
宁顺卫  金韬  张宇  刘皓 《电讯技术》2002,42(1):76-80
本文对MDF远端集中监控系统进行了系统性概述,重点介绍了系统中列告警单元的工作原理以及电路实现。  相似文献   
8.
本文从ADSL建设方式和维护特点出发,指出了引起电信测量台MDF空间紧张问题的根源,列举了目前解决这个问题的办法.并结合江苏省电信有限公司南京分公司对这个问题的认识、思考和实践,从一个全新的角度诠释和解决了MDF资源紧张的问题,介绍了DSLAM工程施工的新工艺,以优化网络结构、提高运营效率,为ADSL可持续发展打下了坚实的基础.  相似文献   
9.
This paper presents a high throughput size-configurable floating point (FP) Fast Fourier Transform (FFT) processor, having implemented the 8-parallel multi-path delay feedback (MDF) functions suitable for applications in the real-time radar imaging system. With regard to floating-point FFT design, to acquire a high throughput with restricted area and power consumptions poses as a greater challenge due to some higher degrees of complexity involved in realizing of FP operations than those fixed-point counterparts. To address the related issues, a novel mixed-radix FFT algorithm featuring the single-sided binary-tree decomposition strategy is proposed aiming at effectively containing the complexity of multiplications for any 2k-point FFT. To this aid, the parallel-processing twiddle factor generator and the dual addition-and-rounding fused FP arithmetic units are optimized to meet the high accuracy demand in computation and the low power budget in implementation. The proposed FP FFT processor has been designed in silicon based on SMIC's 28 nm CMOS technology with the active area of 1.39 mm2. The prototype design delivers a throughput of 4 GSample/s at 500 MHz, at a peak power consumption of 84.2 mW. Thus, the proposed design approach achieves a significant improvement in power efficiency approximately by 14 times on average over some other FP FFT processors previously reported.  相似文献   
10.
给出了一种利用公用电话网(PSTN)的远程分布式总配线架(MDF)集中监控系统的设计与实现方案,介绍了系统的结构原理、内部数据通信约定和监控仪的设计实现。研究表明,该系统既能解决无人值守的分布式远程MDF监控,又具有扩充电信业务的应用前景。  相似文献   
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