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71.
针对因中文食品安全文本特征表达困难,而造成语义信息缺失进而导致分类器准确率低下的问题,提出一种基于深度神经网络的跨文本粒度情感分类模型。以食品安全新闻报道为目标语料,采用无监督的浅层神经网络初始化文本的词语级词向量。引入递归神经网络,将预训练好的词向量作为下层递归神经网络(Recursive Neural Network)的输入层,计算得到具备词语间语义关联性的句子特征向量及句子级的情感倾向输出,同时动态反馈调节词向量特征,使其更加接近食品安全特定领域内真实的语义表达。然后,将递归神经网络输出的句子向量以时序逻辑作为上层循环神经网络(Recurrent Neural Network)的输入,进一步捕获句子结构的上下文语义关联信息,实现篇章级的情感倾向性分析任务。实验结果表明,联合深度模型在食品安全新闻报道的情感分类任务中具有良好的效果,其分类准确率和F1值分别达到了86.7%和85.9%,较基于词袋思想的SVM模型有显著的提升。 相似文献
72.
73.
利用热力学基础数据和相关软件对F-T合成催化剂COS和H_2S中毒的热力学进行了计算。在热力学上,Ru、Fe、Co的COS中毒在F-T合成反应可以发生的条件下均是自发过程。F-T合成反应体系中10~(-9)级的COS即可使Ru基催化剂中的金属Ru生成RuS_2而中毒。Fe和Co毒化后生成的硫化物种类较多,对这些反应的热力学计算结果表明,对于不同的反应,其平衡常数的差异很大,对应中毒反应发生时,所需的COS和H_2S的浓度也不同,对COS的要求更为严格。由于Fe基F-T合成催化剂活性相的复杂性,利用对催化剂相关性质的修饰开发具有一定抗硫性的铁基F-T合成催化剂是可行的;对于Co催化剂,利用F-T合成的反应特点和催化剂改性开发具有一定抗硫性催化剂是可能的。 相似文献
74.
Lamarque M Tastet C Poncet J Demettre E Jouin P Vial H Dubremetz JF 《Proteomics. Clinical applications》2008,2(9):1361-1374
The Plasmodium falciparum food vacuole (FV) is a lysosome-like organelle where erythrocyte hemoglobin digestion occurs. It is a favorite target in the development of antimalarials. We have used a tandem mass spectrometry approach to investigate the proteome of an FV-enriched fraction and identified 116 proteins. The electron microscopy analysis and the Western blot data showed that the major component of the fraction was the FV and, as expected, the majority of previously known FV markers were recovered. Of particular interest, several proteins involved in vesicle-mediated trafficking were identified, which are likely to play a key role in FV biogenesis and/or FV protein trafficking. Recovery of parasite surface proteins lends support to the cytostomal pathway of hemoglobin ingestion as a FV trafficking route. We have identified 32 proteins described as hypothetical in the databases. This insight into FV protein content provides new clues towards understanding the biological function of this organelle in P. falciparum. 相似文献
75.
Olli Varis 《国际水》2013,38(4):624-637
Abstract The Nile brings virtually no water to the sea. The mighty basin with 1/10 of Africa's land area and 1/3 of its population, has only 1/16 of its water. The riparian countries use practically all of the Nile's water and they face increasing challenges in terms of environmental degradation, food security, and socioeconomic development. The geopolitical situation blocks the integrated development of water resources in the basin scale, yet the political environment may be improving. The Nile basin is among the most critical regions of the world in terms of water resources development. In this article, the trends of the major driving forces within the basin countries—population, urbanization, climate, agriculture, economy, human resources, and governance—are scrutinized from the viewpoint of their impacts on water resources and their management. A comparison is made to four other critical macroregions: China, South Asia, Southeast Asia, and West Africa. 相似文献
76.
Frank Lipnizki 《哈尔滨工业大学学报(英文版)》2012,19(1):75-78
Despite the efforts to reduce its water consumption,the food industry still requires large amounts of water.Membrane processes have established themselves in the food industry at the beginning of the w... 相似文献
77.
"国以民为本,民以食为天",食品安全事关国计民生。近期我国食品安全问题频繁发生,知名品牌卷入食品安全问题的漩涡之中。通过博弈分析,本文认为我国食品安全监管存在"激励悖论",建立和完善食品安全监管体系的三重约束和三道防线是解决我国食品安全问题的有效途径和重要手段。 相似文献
78.
赵建民 《四川烹饪高等专科学校学报》2013,(2):8-9,21
英国作家J.A.G.罗伯茨先生的《东食西渐》一书,是从一个真正意义上的西方人的视角,运用丰富翔实的英文书籍资料,包括一些珍贵的历史图片撰写而成,而且这些资料在中国国内几乎是找不到的。他从一个生活在中国本土的中国学者无法做到的研究角度,对中国饮食文化自18世纪以来在西方的传播渗透与普及流行进行了深度的介绍与揭示。其深远的文化意义与历史贡献是不言而喻的。 相似文献
79.
淮扬饮食文化景观谱系的构建是深度挖掘整理淮扬菜文化基因,形成系统保护与传承体系的基础性工作.在对旅游景观谱系相关研究进行系统梳理的基础上,将饮食文化景观谱系的结构分为景观元、景观点和景观走廊三个层次,结合文献分析和专家意见,构建淮扬饮食文化景观谱系.淮扬饮食文化景观谱系对促进城市旅游资源的深度开发、促进旅游产品内涵拓展具有重要作用,对推进城市旅游转型和推广城市旅游形象等方面也具有重要的价值. 相似文献
80.
Mahdi Ghasemi-Varnamkhasti Seyed Saeid MohtasebiMaria Luz Rodriguez-Mendez Jesus LozanoSeyed Hadi Razavi Hojat AhmadiConstantin Apetrei 《Expert systems with applications》2012,39(4):4315-4327
Sensory evaluation is the application of knowledge and skills derived from several different scientific and technical disciplines, physiology, chemistry, mathematics and statistics, human behavior, and knowledge about product preparation practices. This research was aimed to evaluate aftertaste sensory attributes of commercial non-alcoholic beer brands (P1, P2, P3, P4, P5, P6, P7) by several chemometric tools. These attributes were bitter, sour, sweet, fruity, liquorice, artificial, body, intensity and duration. The results showed that the data are in a good consistency. Therefore, the brands were statistically classified in several categories. Linear techniques as Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) were performed over the data that revealed all types of beer are well separated except a partial overlapping between zones corresponding to P4, P6 and P7. In this research, for the confirmation of the groups observed in PCA and in order to calculate the errors in calibration and in validation, PLS-DA technique was used. Based on the quantitative data of PLS-DA, the classification accuracy values were ranked within 49-86%. Moreover, it was found that the classification accuracy of LDA was much better than PCA. It shows that this trained sensory panel can discriminate among the samples except an overlapping between two types of beer. Also, two types of artificial networks were used: Probabilistic Neural Networks (PNN) with Radial Basis Functions (RBF) and FeedForward Networks with Back Propagation (BP) learning method. The highest classification success rate (correct predicted number over total number of measurements) of about 97% was obtained for RBF followed by 94% for BP. The results obtained in this study could be used as a reference for electronic nose and electronic tongue in beer quality control. 相似文献