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BackgroundThe last decade has noticed the expansion of green materials, which aims to reduce the human impact on the environment. Green polymers are clearly tendency subdivision of this stream and numerous bio-sourced plastics have been developed. Recent research has further focused on the development of new bio-based materials such as edible/biodegradable films for food products.Scope and approachFish gelatin (FG), a protein with recreatable reserve, biodegradability, and processability, has a remarkable potential in bio-packaging. However, there have been noticeable issues concerning the use of FG as packing material, including its low mechanical strength, poor moisture stability, and poor water barrier properties. This paper aims to review the state-of-the-art in development of FG-based films and highlights how they play a crucial role in modifying the properties of such films. Various types of nanofillers that have been included into FG to fabricate bio-nanocomposite films, such as nanoclays (montmorillonite, sepiolite), polysaccharide nanofillers (nanowhiskers/nanofibers), metal ions (silver, copper) and metal oxides nanoparticles (ZnO, TiO2) are reviewed.Key findings and conclusionsCross-linking is a promising technique to improve the performance and applicability of FG-based biomaterials, particularly respecting their water sensitivity, which hinders many of their potential uses as food contact materials. Bio-nanocomposite technology may help to make high-performance materials with extra bio-functional properties, and it is anticipated to be a dynamic research in the future. In general, more research is required to ameliorate application processes of FG films, especially physical aspects, to be suitable for bio-packaging application.  相似文献   
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人像智能分析指的是对视频或录像中的人像进行结构化和可视化分析,对目标人物进行性别、年龄、发型等特征的智能识别,这项技术在视频侦查中有极高的应用价值。人像识别早期的算法是通过人工提取特征,通过学习低级视觉特征来针对不同属性进行分类学习,这种基于传统方法的模型表现常常不尽如人意。在计算机视觉领域,通过海量图像数据学习的神经网络比传统方法有更丰富的信息量和特征可以被提取。文章尝试通过深度学习技术训练神经网络模型对行人进行检测和识别,对于衣着不同的行人进行智能识别,具有更好的鲁棒性,提升了视频人像识别的准确率,拓展了人工智能技术在身份识别领域的应用。  相似文献   
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全媒体技术的发展推动我们进入全媒体时代,在全媒体时代下,综艺晚会要以引领大众的审美潮流以及与观众保持较强的互动作为发展方向。总结了全媒体时代下综艺晚会的有效发展策略,包括精心策划、利用高科技等。  相似文献   
4.
Employing an effective learning process is a critical topic in designing a fuzzy neural network, especially when expert knowledge is not available. This paper presents a genetic algorithm (GA) based learning approach for a specific type of fuzzy neural network. The proposed learning approach consists of three stages. In the first stage the membership functions of both input and output variables are initialized by determining their centers and widths using a self-organizing algorithm. The second stage employs the proposed GA based learning algorithm to identify the fuzzy rules while the final stage tunes the derived structure and parameters using a back-propagation learning algorithm. The capabilities of the proposed GA-based learning approach are evaluated using a well-examined benchmark example and its effectiveness is analyzed by means of a comparative study with other approaches. The usefulness of the proposed GA-based learning approach is also illustrated in a practical case study where it is used to predict the performance of road traffic control actions. Results from the benchmarking exercise and case study effectively demonstrate the ability of the proposed three stages learning approach to identify relevant fuzzy rules from a training data set with a higher prediction accuracy than alternative approaches.  相似文献   
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In this article, we report the formation of the high-entropy Gd20Tb20Dy20Al20M20 (M = Fe, Co and Ni) bulk metallic glasses with good magnetocaloric properties. Compared with most of the rare earth based metallic glasses, these alloys are found to have the comparably large maximum magnetic entropy changes (ΔSM), but much broader widths of the ΔSM peaks, and hence larger refrigerant capacity (RC). This can be attributed to the combination of the spin glass behaviors and the complicated compositions in these alloys. Our work show that the high entropy bulk metallic glasses is a promising candidate material as the magnetic refrigerant.  相似文献   
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铁皮石斛多糖抗癌及免疫活性研究   总被引:1,自引:0,他引:1  
研究了铁皮石斛多糖的抗癌及免疫活性。水提醇沉法提取铁皮石斛多糖,将其作用于癌细胞株(HepG2、A549、F9、NCCIT)和小鼠脾脏细胞、腹腔巨噬细胞,观察细胞形态变化,并用MTT法分析其对细胞增殖的作用。结果表明:铁皮石斛多糖能抑制癌细胞的增殖并促进脾脏细胞生长,铁皮石斛多糖具有一定的抗癌活性及免疫活性。  相似文献   
9.
采用积分方程法推导出求解桩-桩、桩-土、土-土之间的相互作用系数所需要的第二类Fredholm积分方程,利用叠加原理对长短桩桩筏基础进行计算分析,通过与其它计算方法的比较验证了计算方法的正确性.并对长短桩桩筏基础的沉降、各桩以及土之间的荷载分担情况进行了分析.该方法可以用来分析大规模的长短桩桩筏基础,具有较好的工程应用前景.  相似文献   
10.
大跨度变截面拱形立体管桁架施工技术   总被引:1,自引:0,他引:1  
程勤功  金振  毕庆槐 《建筑技术》2007,38(5):326-329
根据工程特点与场地条件,浙江财经学院体育中心24榀大跨度变截面拱形立体管桁架,采用地面拼装和空中拼装相结合的方法施工,拼装质量良好,焊接变形应力控制在设计要求范围内。  相似文献   
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