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31.
汇文电子阅览室管理系统的应用分析 总被引:1,自引:0,他引:1
赵明霞 《农业图书情报学刊》2009,21(4):180-182
对汇文电子阅览室管理系统主要功能、特点进行了分析,指出了该系统的主要优、缺点;指出电子阅览室管理系统的发展趋势将是能够实现无人值守。 相似文献
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电子商务专业人才培养研究 总被引:4,自引:0,他引:4
本文论述了我国与国外电子商务专业人才培养情况 ,以及当前国内电子商务人才的需求状况 ,从而确立我国电子商务人才培养方向。 相似文献
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本文运用SCM的基础理论,阐述了在当前信息技术环境下SCM模式的运用,探讨了目前我国森工企业在运用SCM模式中所存在的一些问题和误区。 相似文献
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Paul Joseph Dimitri Bakirtzis Audrey Vieille 《Wood material science & engineering》2015,10(1):130-144
AbstractSaving lives and properties are of primary importance in fire disasters. Unfortunately, current fire detectors are not fast enough to allow the detection of many fires, especially, at the smouldering stages. Some preliminary studies on laevoglucosan (LG), as an important product from cellulose degradation, have shown interesting properties and could be detected by devices classified as “electronic noses” (e-noses). In the present work, the mechanisms of pyrolysis of some ligno-cellulosic materials were investigated using thermo-gravimetric analysis, differential scanning calorimetry, Fourier transform infrared spectroscopy and by a tube furnace with a view to determining the major degradation products from wood, white paper and cardboard samples. Additionally, an odour sensor, made of tin oxide semiconductor thin film, was employed to evaluate its sensitivity in detecting LG. It was found that LG can be readily found among the thermal degradation products of cellulosic materials in question, and that the metal oxide sensor employed was sufficiently sensitive in detecting its presence. Therefore, the work opens up the potential of using such a sensor as an “e-nose” for the early detection of fires stemming from forest product fire loads in storage places and in other enclosures. 相似文献
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EFFECTS OF FLUID AND COMPUTED TOMOGRAPHIC TECHNICAL FACTORS ON CONSPICUITY OF CANINE AND FELINE NASAL TURBINATES
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Raimonda Uosyte Darren J. Shaw Danielle A. Gunn‐Moore Eduardo Fraga‐Manteiga Tobias Schwarz 《Veterinary radiology & ultrasound》2015,56(5):494-502
Turbinate destruction is an important diagnostic criterion in canine and feline nasal computed tomography (CT). However decreased turbinate visibility may also be caused by technical CT settings and nasal fluid. The purpose of this experimental, crossover study was to determine whether fluid reduces conspicuity of canine and feline nasal turbinates in CT and if so, whether CT settings can maximize conspicuity. Three canine and three feline cadaver heads were used. Nasal slabs were CT‐scanned before and after submerging them in a water bath; using sequential, helical, and ultrahigh resolution modes; with images in low, medium, and high frequency image reconstruction kernels; and with application of additional posterior fossa optimization and high contrast enhancing filters. Visible turbinate length was measured by a single observer using manual tracing. Nasal density heterogeneity was measured using the standard deviation (SD) of mean nasal density from a region of interest in each nasal cavity. Linear mixed‐effect models using the R package ‘nlme’, multivariable models and standard post hoc Tukey pair‐wise comparisons were performed to investigate the effect of several variables (nasal content, scanning mode, image reconstruction kernel, application of post reconstruction filters) on measured visible total turbinate length and SD of mean nasal density. All canine and feline water‐filled nasal slabs showed significantly decreased visibility of nasal turbinates (P < 0.001). High frequency kernels provided the best turbinate visibility and highest SD of aerated nasal slabs, whereas medium frequency kernels were optimal for water‐filled nasal slabs. Scanning mode and filter application had no effect on turbinate visibility. 相似文献
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为探究臭氧气浮漂洗对鲢鱼糜的除腥效果,以鲢鱼糜为试验材料,采用电子鼻结合顶空-固相微萃取-气质联用法(HS-SPME-GC-MS)检测分析传统漂洗和臭氧气浮漂洗后鲢鱼糜的挥发性成分,寻找其腥味来源。结果显示:鲢鱼糜中共检测到24种挥发性物质。与传统漂洗鱼糜相比,经过臭氧气浮漂洗后,鱼糜中挥发性成分减少,己醛、庚醛、壬醛、癸醛、1-辛烯-3-醇等对鱼腥味贡献较大物质的相对含量皆有所降低,而1-甲基-4-硝甲基-哌啶和5-甲基-2-苯基-吲哚等其他化合物并未被检测出。电子鼻的PCA分析结果与HS-SPME-GC-MS检测结果相一致。结果表明,使用臭氧气浮漂洗鱼糜相比传统漂洗可有效减轻鱼糜腥味,漂洗时间应控制在10~15 min。 相似文献