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111.
为解决传统人脸属性分类训练效率低、模型参数量巨大等问题,本文提出了一种多网络学习框架.该框架包含两个子网络:人脸区域定位网络和属性分类网络,从而实现动态选择不同的人脸区域进行人脸属性预测.此外,本文提出了基于提示的模型压缩技术,在不明显降低准确率的前提下大大压缩网络参数.最后,通过仿真在CelebA人脸属性分类数据集上...  相似文献   
112.
The present work evaluated the ability of near infrared (NIR) spectroscopy in predicting some sensory attributes of 20 Emmental cheeses originating from different European regions. For the purpose of this study four appearance and texture attributes, namely, adhesivity, friability, elasticity and firmness and six olfacto-gustatory attributes namely, aroma intensity, odour intensity, bitterness, saltiness, acidity and sweetness were selected by the sensory panel. Calibration models between sensory properties and NIR spectra were developed using partial least squares (PLS) regression. The squared correlation coefficients (R2) were greater than 0.5 for adhesivity, elasticity, firmness, aroma, bitterness, saltiness, acidity and sweetness. In addition, a good correlation between sensory attributes and NIR spectra was found using canonical correlation analysis (CCA). Therefore, this work demonstrates the feasibility of NIR to predict some sensory attributes since a relatively high correlation between sensory data and NIR spectra was found. However, further research with a large data bases will be needed in order to validate the method.  相似文献   
113.
‘B 10’ carambola of ripening stage (RS) 3 and 4 were minimally processed (MP) and then dipped in 0, 15 and 30 mg L?1 ascorbic acid (AA). The 1‐cm‐thick slices were then dried, packed into cling‐wrapped‐foam tray and stored at 7 °C for 0, 3 and 5 days. Skin colour (L*, C* and h°), flesh firmness, soluble solids concentration, vitamin C content, titratable acidity, pH, degree of browning, polyphenoloxidase (PPO) activity and sensory attributes of MP carambola treated with AA were determined. AA treatment had significant effect in decreasing cut surface browning degree but no significant effect on all the selected quality characteristics of the MP carambola. In the sensory evaluation, flesh colour, sweetness, flavour and overall taste were significantly affected by AA treatment especially at 15 mg L?1. The RS of fruit significantly affected skin colour (C* and h°), pH and sensory attributes of colour and flavour of the MP carambola. As storage day (SD) progressed, skin colour (C* and h°), flesh firmness and vitamin C content, cut surface browning, PPO activity and all the sensory attributes of MP carambola decreased significantly. Flesh firmness of the MP carambola was affected by the interaction between AA × SD. Sensory attributes of MP carambola were affected significantly by AA × RS. All the sensory attributes of MP carambola positively correlated to each other but negatively correlated with browning degree. PPO activity positively correlated with browning degree. Copyright © 2007 Society of Chemical Industry  相似文献   
114.
Liu L  Kerry JF  Kerry JP 《Meat science》2007,75(2):196-202
Casings formed from pectin (PN) containing 2.5% and 5% corn oil (CO) and olive oil (OO) and gelatine/sodium alginate blends (GSAB) containing 2.5% CO and OO respectively were used for sausage manufacture. Mechanical properties and water content of casings were assessed prior to application. Following sausage manufacture, product quality and shelf-life evaluation were assessed in terms of sensory attributes, instrumental colour, moisture loss and lipid oxidation. All manufactured casings were of good quality and initially produced intact and stable sausage products. However, with time, shrinkage of products occurred where GSAB casings were used. Sensory analysis of sausages showed that PN casings were more preferred to GSAB casings for sausage manufacture. CIE colour analysis supported sensory evaluation. Water losses from sausages using GSAB casings were lower compared to sausages using PN casings due to GSAB casings having higher ability to trap and absorb water compared to PN casings. Lipid oxidation developed over time for all sausage products, however, sausages manufactured using GSAB casings containing both CO and OO at 2.5% had better oxygen barrier properties compared to sausages manufactured using PN containing the same concentration of emulsified oils. Sausages manufactured using casings containing OO were more prone to lipid oxidation than those using CO. Importantly, sausages manufactured using PN casings containing 5.0% CO were extremely stable to lipid oxidation over a six day storage period and significantly, were <1 on the TBARS numbers scale.  相似文献   
115.
116.
This paper uses the value brand model in an attempt to determine the factors affecting post-adoption intentions through brand loyalty for the mobile data services. Data were collected online from 1266 respondents. The structural equation modeling was used to test the research model. The results show that post-adoption intentions are directly influenced by intangible attributes. Product deliverables and intangible attributes indirectly affect post-adoption intentions via m-brand loyalty. However, the results of current research do not show any effects of price on post-adoption intentions. The results also show genders differences in post-adoption intentions. Practical suggestions are provided. This paper advances our knowledge of post-adoption variations in business–consumer contexts and mobile business from the perspectives of utilitarian and non-utilitarian values of the mobile data services. This paper also contributes to the theory of post-adoption by offering across-gender examination.  相似文献   
117.
The effects of conventional (CV) and microwave (MW) heating on total soluble solid (TSS) content, total anthocyanin content (TAC), total phenolic content (TPC) and antioxidant activity of raspberry juice obtained from two cultivars of Amol (AM) and Siyahkal (SK) were scrutinised. Antioxidant activity of the juices was measured by 2,2 diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging capacity and expressed as EC50 value. In the both methods, the concentration rate constant for the juices was significantly decreased by increasing operational pressure from 12 to 100 kPa (< 0.05). A first‐order reaction kinetic model was successfully fitted for the degradation of monomeric anthocyanins at all operating pressures. The results also showed that thermal treatment of MW compared CV in both SK and AM cultivars caused a lower decrease in the TAC, TPC and antioxidant activity. Moreover, the changes in trend of the antioxidant activities due to the thermal treatment were positively correlated with the TPC (= 0.74, < 0.05) and TAC (= 0.61, < 0.05).  相似文献   
118.
A method of combining learning algorithms is described that preserves attribute-efficiency. It yields learning algorithms that require a number of examples that is polynomial in the number of relevant variables and logarithmic in the number of irrelevant ones. The algorithms are simple to implement and realizable on networks with a number of nodes linear in the total number of variables. They include generalizations of Littlestone's Winnow algorithm, and are, therefore, good candidates for experimentation on domains having very large numbers of attributes but where nonlinear hypotheses are sought.  相似文献   
119.
The total ascorbic acid contents and the antioxidant capacity in green beans and in peas were measured during deep-frozen storage and compared to storage at 4 °C and 20 °C. In green beans only, the flavonols quercetin and kaempferol were measured. The results were correlated with sensory attributes which were evaluated at the same storage stages. The total ascorbic acid content is a good parameter for the storage time of both vegetables and showed, for peas, a positive correlation with the attribute “sweet taste” and a negative correlation with the attribute “musty” odour. The total ascorbic acid content of green beans was positively correlated with a “squeaky” texture and negatively with a “musty” taste. The flavonol content and the antioxidant capacity were more stable during the storage process and showed less correlation with sensory attributes.  相似文献   
120.
三维AVO处理方法及应用   总被引:3,自引:0,他引:3  
AVO处理的基础是其振幅处理,真振幅处理主要通过振幅补偿及地表一致性振幅校正等手段完成。反褶积在提高地震波高频成分的同时,也破坏了地震波振幅原有的振幅关系,反褶积后需要重新作振幅校正。速度分析及剩余静校正将直接影响AVO分析的效果,做好速度分析及剩余静校正有利于提高AV0分析的准确性。利用叠前时间偏移产生的CRP道集代替CDP道集作AVO分析,克服了CDP道集的不足,使AVO属性得到偏移归位,气藏边界更加清楚。利用本文提出的三维AVO处理方法,对永安镇地区的三维资料进行了AV0处理,对已知的气藏进行了准确的气藏AVO描述,充分说明该三维AVO处理方法是非常可靠的,具有广阔的应用前景。  相似文献   
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