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A Normalizing Flow-Based Bidirectional Mapping Residual Network for Unsupervised Defect Detection
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作者 Lanyao Zhang Shichao Kan +3 位作者 Yigang Cen Xiaoling Chen Linna Zhang Yansen Huang 《Computers, Materials & Continua》 SCIE EI 2024年第2期1631-1648,共18页
Unsupervised methods based on density representation have shown their abilities in anomaly detection,but detection performance still needs to be improved.Specifically,approaches using normalizing flows can accurately ... Unsupervised methods based on density representation have shown their abilities in anomaly detection,but detection performance still needs to be improved.Specifically,approaches using normalizing flows can accurately evaluate sample distributions,mapping normal features to the normal distribution and anomalous features outside it.Consequently,this paper proposes a Normalizing Flow-based Bidirectional Mapping Residual Network(NF-BMR).It utilizes pre-trained Convolutional Neural Networks(CNN)and normalizing flows to construct discriminative source and target domain feature spaces.Additionally,to better learn feature information in both domain spaces,we propose the Bidirectional Mapping Residual Network(BMR),which maps sample features to these two spaces for anomaly detection.The two detection spaces effectively complement each other’s deficiencies and provide a comprehensive feature evaluation from two perspectives,which leads to the improvement of detection performance.Comparative experimental results on the MVTec AD and DAGM datasets against the Bidirectional Pre-trained Feature Mapping Network(B-PFM)and other state-of-the-art methods demonstrate that the proposed approach achieves superior performance.On the MVTec AD dataset,NF-BMR achieves an average AUROC of 98.7%for all 15 categories.Especially,it achieves 100%optimal detection performance in five categories.On the DAGM dataset,the average AUROC across ten categories is 98.7%,which is very close to supervised methods. 展开更多
关键词 Anomaly detection normalizing flow source domain feature space target domain feature space bidirectional mapping residual network
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ON THE SHARP GROWTH,COVERING THEOREMS FOR NORMALIZED BIHOLOMORPHIC MAPPINGS IN C^n 被引量:2
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作者 刘小松 刘太顺 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期803-812,共10页
In this article, a normalized biholomorphic mapping f defined on bounded starlike circular domain in Cn is considered, where z = 0 is a zero of order k + 1 of f(z) - z. The sharp growth, covering theorems for almos... In this article, a normalized biholomorphic mapping f defined on bounded starlike circular domain in Cn is considered, where z = 0 is a zero of order k + 1 of f(z) - z. The sharp growth, covering theorems for almost starlike mappings of order α and starlike mappings of order α are established. Meanwhile, the construction of the above mappings on bounded starlike circular domain in Cn is also discussed, it provides the extremal mappings for the growth, covering theorems of the above mappings. 展开更多
关键词 Zero of order k 1 normalized biholomorphic mappings almost starlike mappings of order α starlike mappings of order α GROWTH covering theorems
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On the Normal Criterion of Quasimeromorphic Mappings
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作者 Deng Fang\|wen College of Mathematics and Statistics, Wuhan University, Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2001年第3期621-625,共5页
In this paper, we generalize an, inequality of meromorphic mappings to quasimeromorphic ones. Applying the results here, we can establish a normal criterion of quasimeromorphic mappings.
关键词 quasimeromorphic mapping covering surface normal criterion
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Normalized edge detection, and the horizontal extent and depth of geophysical anomalies 被引量:2
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作者 李丽丽 韩立国 黄大年 《Applied Geophysics》 SCIE CSCD 2014年第2期149-157,252,253,共11页
Edge detection is an image processing technique for finding the boundaries of objects within images. It is typically used to interpret gravity and magnetic data, and find the horizontal boundaries of geological bodies... Edge detection is an image processing technique for finding the boundaries of objects within images. It is typically used to interpret gravity and magnetic data, and find the horizontal boundaries of geological bodies. Large deviations between model and true edges are common because of the interference of depth and errors in computing the derivatives; thus, edge detection methods cannot provide information about the depth of the source. To simultaneously obtain the horizontal extent and depth of geophysical anomalies, we use normalized edge detection filters, which normalize the edge detection function at different depths, and the maxima that correspond to the location of the source. The errors between model and actual edges are minimized as the depth of the source decreases and the normalized edge detection method recognizes the extent of the source based on the maxima, allowing for reliable model results. We demonstrate the applicability of the normalized edge detection filters in defining the horizontal extent and depth using synthetic and actual aeromagnetic data. 展开更多
关键词 geophysical anomalies normalized edge detection normalized total horizontal derivative regularization tilt angle theta map
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基于Normal Map虚拟技术的赣南客家围屋仿真实现探析 被引量:2
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作者 王志强 王犹建 《湖北科技学院学报》 2016年第4期12-16,共5页
Normal Map技术是当前虚拟仿真实现的一个重要手段,它在模型基础上通过贴图信息来完成虚拟对象的高仿真实现。当前古建筑虚拟仿真的数字化实现更是离不开Normal Map技术的支撑。赣南客家围屋是江西古建筑群里极具代表性建筑,其历史悠久... Normal Map技术是当前虚拟仿真实现的一个重要手段,它在模型基础上通过贴图信息来完成虚拟对象的高仿真实现。当前古建筑虚拟仿真的数字化实现更是离不开Normal Map技术的支撑。赣南客家围屋是江西古建筑群里极具代表性建筑,其历史悠久,文化深厚,建筑形制及材料十分丰富,Normal Map虚拟技术的研究将为赣南客家建筑的保护提供技术支持。本文从Normal Map的运算方式及技术特点,结合赣南客家围屋的具体实际进行建筑微观细节的仿真实现探析。 展开更多
关键词 赣南客家围屋 normal map技术 虚拟仿真
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利用面片阴影法简化Bump Mapping
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作者 蒋立华 熊海桥 +1 位作者 罗轶先 刘晓东 《计算机工程与应用》 CSCD 北大核心 2003年第18期67-68,201,共3页
论文介绍了Bump Mapping的生成方法,并针对可分割bump形式的纹理提出了利用OpenGL简化计算和加速显示的方法———面片阴影算法,即利用面片的阴影降低逐点计算的复杂性。
关键词 0penGL BUMP mapping 法向量 纹理
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多回波快速自旋回波T_2 mapping定量技术评价心肌T_2值的价值
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作者 刘明熙 张挽时 +5 位作者 张子衡 孟利民 徐先荣 田建伟 龚万沣 刘洁 《武警医学》 CAS 2015年第10期1031-1035,1038,共6页
目的探讨多回波快速自旋回波序列(MEFSE)的T2mapping定量技术评价左室心肌T2值的价值。方法 30例健康志愿者,均行3.0T心脏磁共振(CMR)Cine电影、T2WI序列、MEFSE T2mapping序列扫描,依据描述性研究方法,探索MEFSE T2mapping序列临床应... 目的探讨多回波快速自旋回波序列(MEFSE)的T2mapping定量技术评价左室心肌T2值的价值。方法 30例健康志愿者,均行3.0T心脏磁共振(CMR)Cine电影、T2WI序列、MEFSE T2mapping序列扫描,依据描述性研究方法,探索MEFSE T2mapping序列临床应用的可行性和可重复性,测定感兴趣区T2值,应用方差分析方法统计分析心肌17节段和不同供血区下有无差异。应用Bland^Altman分析和Pearson相关分析方法研究此技术在不同观察者间的一致性。结果健康志愿者17节段心肌T2值不全相等(P<0.01)。不同冠状动脉供血区T2值无统计学差异(F=1.656,P=0.192)。左室心肌平均T2值如下:基底部,(71.6±7.1)ms;中间部,(77.3±9.2)ms;心尖部,(83.0±8.5)ms,差异有统计学意义(F=14.245,P<0.01)。根据Bland-Altman一致性分析和Pearson相关分析得到参数测量在观察者间具有良好的一致性,95%一致性界限(-6.1,24.8)ms,相关系数r=0.809。结论 CMR MEFSE T2mapping定量技术在心脏成像中具有较好的可行性和可重复性。中国健康志愿者中心肌T2值存在节段性差异。 展开更多
关键词 心脏磁共振 T2 mapping 健康志愿者
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LINEAR DILATATION OF QUASIREGULAR MAPPINGS IN SPACE 被引量:2
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作者 陈克应 《Acta Mathematica Scientia》 SCIE CSCD 2001年第2期213-220,共8页
This paper presents an explicit upper bound for the linear dilatation of K- quasiregular (K-qr) mappings, which improves S. Rickman's [6, P.37] corresponding re- sult for K-qr mappings and generalizes P. Seittenra... This paper presents an explicit upper bound for the linear dilatation of K- quasiregular (K-qr) mappings, which improves S. Rickman's [6, P.37] corresponding re- sult for K-qr mappings and generalizes P. Seittenranta's [7, Theorem 1.5] result for K- quasiconformal (K-qc) maps. 展开更多
关键词 K-qr mapping K-qc map linear dilatation local index MODULUS normal domain
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Dry/wet snow mapping based on the synergistic use of dual polarimetric SAR and multispectral data 被引量:2
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作者 Divyesh VARADE Onkar DIKSHIT Surendar MANICKAM 《Journal of Mountain Science》 SCIE CSCD 2019年第6期1435-1451,共17页
We propose a multi-sensor multi-spectral and bi-temporal dual-polarimetric Synthetic Aperture Radar(SAR) data integration scheme for dry/wet snow mapping using Sentinel-2 and Sentinel-1 data which are freely available... We propose a multi-sensor multi-spectral and bi-temporal dual-polarimetric Synthetic Aperture Radar(SAR) data integration scheme for dry/wet snow mapping using Sentinel-2 and Sentinel-1 data which are freely available to the research community. The integration is carried out by incorporating the information retrieved from ratio images of the conventional method for wet snow mapping and the multispectral data in two different frameworks. Firstly, a simple differencing scheme is employed for dry/wet snow mapping, where the snow cover area is derived using the Normalized Differenced Snow Index(NDSI). In the second framework, the ratio images are stacked with the multispectral bands and this stack is used for supervised and unsupervised classification using support vector machines for dry/wet snow mapping. We also investigate the potential of a state of the art backscatter model for the identification of dry/wet snow using Sentinel-1 data. The results are validated using a reference map derived from RADARSAT-2 full polarimetric SAR data. A good agreement was observed between the results and the reference data with an overall accuracy greater than 0.78 for the different blending techniques examined. For all the proposed frameworks, the wet snow was better identified. The coefficient of determination between the snow wetness derived from the backscatter model and the reference based on RADARSAT-2 data was observed to be 0.58 with a significantly higher root mean square error of 1.03 % by volume. 展开更多
关键词 SNOW mapping Ratio method normalized Differenced SNOW Index Classification Polarimetric synthetic-aperture radar
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NORMAL CRITERION FOR FAMILIES OF HOLOMORPHIC MAPS OF SEVERAL COMPLEX VARIABLES INTO P^N(C)WITH MOVING HYPERSURFACES 被引量:1
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作者 涂振汉 曹红哲 《Acta Mathematica Scientia》 SCIE CSCD 2009年第1期169-175,共7页
This article gives a normal criterion for families of holomorphic mappings of several complex variables into P N(C)for moving hypersurfaces in pointwise general position,related to an Eremenko’s theorem.
关键词 Holomorphic mappings moving hypersurfaces normal families Picard the- orems and value distribution theory
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ON PROBLEM OF NEAREST COMMON FIXED POINT OF NONEXPANSIVE MAPPINGS
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作者 张石生 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第7期883-889,共7页
The purpose is by using the viscosity approximation method to study the convergence problem of the iterative scheme for an infinite family of nonexpansive mappings and a given contractive mapping in a reflexive Banach... The purpose is by using the viscosity approximation method to study the convergence problem of the iterative scheme for an infinite family of nonexpansive mappings and a given contractive mapping in a reflexive Banach space. Under suitable conditions, it was proved that the iterative sequence converges strongly to a common fixed point which was also the unique solution of some variational inequality in a reflexive Banach space. The results presented extend and improve some recent results. 展开更多
关键词 sequence of nonexpansive mappings viscosity approximation common fixed point demi-closed principle weakly sequentially continuous duality mapping normalized duality mapping
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QUASIMEROMORPHIC MAPPINGS OF SEVERAL COMPLEX VARIABLES
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作者 周泽华 孙道椿 《Acta Mathematica Scientia》 SCIE CSCD 1999年第S1期541-547,共7页
The definitions of quasimeromorphic mappings from Cn to P1n, where P1 C U {∞}, P1n= P1×P1× ×P1(n-times) are introduced. From an inequality of the value distribution of quasimeromorphic functions of s... The definitions of quasimeromorphic mappings from Cn to P1n, where P1 C U {∞}, P1n= P1×P1× ×P1(n-times) are introduced. From an inequality of the value distribution of quasimeromorphic functions of single variable, it follows that a normal criterion for the family of quasimeromorphic functions of several complex variables. Futhermore, a normal criterion for the family of quasimeromorphic mappings from Cn to P1n has been obtained. 展开更多
关键词 Quasimeromorphic mapping covering number normal family
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Lithological mapping with multispectral data–setup and application of a spectral database for rocks in the Balakot area, Northern Pakistan
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作者 Michael FUCHS Adnan A.AWAN +4 位作者 Sardar S.AKHTAR Ijaz AHMAD Simon SADIQ Asif RAZZAK Naghmah HAIDER 《Journal of Mountain Science》 SCIE CSCD 2017年第5期948-963,共16页
In the frame of landslide susceptibility assessment, a spectral library was created to support the identification of materials confined to a particular region using remote sensing images. This library, called Pakistan... In the frame of landslide susceptibility assessment, a spectral library was created to support the identification of materials confined to a particular region using remote sensing images. This library, called Pakistan spectral library(pklib) version 0.1, contains the analysis data of sixty rock samples taken in the Balakot region in Northern Pakistan.The spectral library is implemented as SQLite database. Structure and naming are inspired by the convention system of the ASTER Spectral Library. Usability, application and benefit of the pklib were evaluated and depicted taking two approaches, the multivariate and the spectral based. The spectral information were used to create indices. The indices were applied to Landsat and ASTER data tosupportthespatial delineation of outcropping rock sequences instratigraphic formations. The application of the indices introduced in this paper helps to identify spots where specific lithological characteristics occur. Especially in areas with sparse or missing detailed geological mapping, the spectral discrimination via remote sensing data can speed up the survey. The library can be used not only to support the improvement of factor maps for landslide susceptibility analysis, but also to provide a geoscientific basisto further analyze the lithological spotin numerous regions in the Hindu Kush. 展开更多
关键词 Lithological mapping Multispectral data Spectral library normalized difference index Northern Pakistan
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A Note of Spirallike Mappings in C^n
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作者 李小申 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第1期52-54, ,共3页
In this paper,the Growth and covering Theorems for a kind of spirallike mapping are given.
关键词 spirallike mappings Growth Theorems normal matrix
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三维人脸深度图的流形学习-LOGMAP识别方法 被引量:11
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作者 詹曙 张芝华 +2 位作者 叶长明 蒋建国 S.Ando 《电子测量与仪器学报》 CSCD 2012年第2期138-143,共6页
人脸识别是生物特征识别技术最友好的身份识别方式,而三维人脸识别由于可解决二维人脸识别中存在的光照、姿态等局限,成为人脸识别的研究热点,但其特征维数过高是该领域的瓶颈,而维数约减是解决这一问题的关键。流形学习是一类非线性维... 人脸识别是生物特征识别技术最友好的身份识别方式,而三维人脸识别由于可解决二维人脸识别中存在的光照、姿态等局限,成为人脸识别的研究热点,但其特征维数过高是该领域的瓶颈,而维数约减是解决这一问题的关键。流形学习是一类非线性维数约减算法,LOGMAP是一种基于黎曼法坐标的流形学习算法,该算法可以在保持度量信息不变的情况下,把高维空间的数据映射到低维空间。构建了基于流形学习的三维人脸识别框架,并结合LOGMAP进行三维人脸深度图的识别。实验结果表明,该方法在三维深度图上可以得到良好的识别效果。 展开更多
关键词 三维深度图 人脸识别框架 流形学习 黎曼法坐标 LOGmap
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MAP译码器的免归一化处理信息更新算法 被引量:6
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作者 王璇 杜军 《电讯技术》 北大核心 2021年第10期1238-1242,共5页
在不改变译码性能的条件下,为了加快最大后验概率(Maximum A Posteriori Probability,MAP)译码器状态信息更新的速度和降低算法的复杂度,提出了一种用于Turbo码的MAP译码器的免归一化处理算法。算法采用二进制补码加法器和减法器将MAP... 在不改变译码性能的条件下,为了加快最大后验概率(Maximum A Posteriori Probability,MAP)译码器状态信息更新的速度和降低算法的复杂度,提出了一种用于Turbo码的MAP译码器的免归一化处理算法。算法采用二进制补码加法器和减法器将MAP译码过程中的状态信息投影到一个归一化圆上,当状态信息更新时所有的状态信息在归一化圆上移动,通过保持归一化圆上状态信息的正确关系来计算似然比。归一化过程中不用搜索或估计状态信息的最大值,通过简化状态信息归一化过程加速了MAP译码器的状态信息更新并降低了复杂度。所提算法在与传统算法译码性能相同的情况下,可以降低36.2%的计算复杂度和17.4%的关键路径延迟,达到MAP译码器实现中的高速、低复杂度目标。 展开更多
关键词 TURBO码 map译码器 免归一化 归一化圆 log_map算法 状态信息
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基于MapGIS数字高程模型基岩面高程等值线图的制作 被引量:2
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作者 张宏鑫 《测绘与空间地理信息》 2015年第6期62-63,共2页
基岩面高程等值线图是建立三维地质模型所需的一项重要数据,也是三维地质调查工作的一项重要任务。制作基岩面高程等值线的主要数据源为钻孔和地形等高线。在制作过程中,首先对钻孔数据进行筛选和标准化处理,筛选出347个钻孔投影成Map ... 基岩面高程等值线图是建立三维地质模型所需的一项重要数据,也是三维地质调查工作的一项重要任务。制作基岩面高程等值线的主要数据源为钻孔和地形等高线。在制作过程中,首先对钻孔数据进行筛选和标准化处理,筛选出347个钻孔投影成Map GIS的点文件(.WT),为提高精度,使成图更符合实际情况,结合武汉市地形特征,提取地表基岩露头出露部分等高线(.WL)代表露头区基岩面高程。再利用Map GIS DTM分析数字高程模型对钻孔和等高线对应的点文件和线文件(.WT和.WL)剖分插值网格化,生成平面和立体的基岩面等值线图。通过对Map GIS提供的4种剖分插值结果进行对比分析,应用Kring泛克里格网格化模型绘制的基岩面高程等值线图更符合实际情况,同时也更快速、方便。需要注意的是,在使用Kring泛克里格网格化方法时,应对数据进行正态分布检验。 展开更多
关键词 基岩面高程等值线 正态分布
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MAPGIS图形参数变异的归一化
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作者 高志勇 邢立新 +1 位作者 元楠楠 陈潇 《吉林大学学报(信息科学版)》 CAS 2015年第1期79-83,共5页
针对MAPGIS非标准制图过程中,多景多区域原参数非同一的图件拼接,文件合并过程中易产生的图元、信息混乱等问题,根据MAPGIS的整图变换、地图参数、图元实际大小的特性,推导并结合3个参量的关系,进行参量统改,实现了多景多区域原参数非... 针对MAPGIS非标准制图过程中,多景多区域原参数非同一的图件拼接,文件合并过程中易产生的图元、信息混乱等问题,根据MAPGIS的整图变换、地图参数、图元实际大小的特性,推导并结合3个参量的关系,进行参量统改,实现了多景多区域原参数非同一图件的归一化处理,得到了投影类型、比例尺、地图参数等关键参数统一的图件。提高了非标准图件的制作效率,为非标准图件标准化提供了方法指导。 展开更多
关键词 mapGIS制图 图形参数变异 整图变换 归一化
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基于SuperMap Objects的太原师范学院中区植物查询系统 被引量:1
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作者 邱丽氚 邱文君 《太原师范学院学报(自然科学版)》 2012年第4期136-141,共6页
基于SuperMap Objects的太原师范学院中区植物查询系统是在软件工程基本原理的指导下,运用SuperMap Objects二次开发组件,在Visual Basic 2008IDE软件开发环境下,开发的植物查询系统,可以对校园植物进行选择、漫游、全副显示、距离测量... 基于SuperMap Objects的太原师范学院中区植物查询系统是在软件工程基本原理的指导下,运用SuperMap Objects二次开发组件,在Visual Basic 2008IDE软件开发环境下,开发的植物查询系统,可以对校园植物进行选择、漫游、全副显示、距离测量等基本空间操作以及图形查属性、属性查图形、SQL查询等功能. 展开更多
关键词 SUPERmap OBJECTS 植物 查询系统 太原师范学院中区
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常温下MAP对红松仁酸价的影响 被引量:2
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作者 王颖 黄晓山 王桂英 《包装工程》 CAS CSCD 北大核心 2010年第3期40-42,共3页
研究常温下MAP对红松籽油酸价的影响,为松仁的科学贮藏提供技术参考。研究结果表明MAP可以较好地抑制松仁的酸败,有利于保持松仁的贮藏品质,其中充入100%N2和100%CO2气体的试样在贮藏期间其酸价的变化相对一致,效果相对其他充气方式较好... 研究常温下MAP对红松籽油酸价的影响,为松仁的科学贮藏提供技术参考。研究结果表明MAP可以较好地抑制松仁的酸败,有利于保持松仁的贮藏品质,其中充入100%N2和100%CO2气体的试样在贮藏期间其酸价的变化相对一致,效果相对其他充气方式较好,建议在常温贮藏中使用。 展开更多
关键词 红松仁 map 常温贮藏 酸价
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