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印楝细胞悬浮培养系的建立及悬浮培养  [PDF]
梁军,魏刚,吕全,贾秀贞,张星耀
林业科学研究 , 2003,
Abstract: 研究了印楝细胞悬浮培养系的建立及印楝细胞悬浮培养的条件。结果表明,印楝细胞悬浮系的建立以B5培养基,NAA2.0~4.0mg?L-1,采用直接倾倒法作为接种方法为好;基于生物量、印楝素含量和印楝素产率综合分析认为,印楝细胞悬浮培养的最佳条件为B5培养基,NAA2~4mg?L-1,蔗糖30g?L-1,培养温度25℃,及根据培养容器的大小选择合适的转速和装液量。
STUDY OF THE EFFECTED GENETIC WATERMARKING ROBUSTNESS UNDER DCT AND DWT DOMAINS
Abduljabbar Shaamala,Azizah A. Manaf
International Journal of New Computer Architectures and their Applications , 2012,
Abstract: Watermarking becomes the suitable technology to protect multimedia in digital world. Watermarking using genetic algorithm for the optimization of the tread- off between the watermarking requirements has attracted the attention of researchers; amongst the watermarking requirements, the robustness is an important one. Watermarking embedded in frequency domain using DWT or DCT can affect the robustness of watermarking, this paper studies the effect of embedding domain on the robustness in genetic watermarking. Results of attacks based on numerical correlation (NC) is analyzed through the paper sections, the DWT results showed more robustness than DCT in watermarking based on GA
Encrpyted and adaptive digital watermarking algorithm in DCT domain
DCT域加密自适应数字水印算法

DING Liu,CHENG Xian-yi,XU Bo,
丁鏐
,程显毅,徐波

计算机应用研究 , 2009,
Abstract: Aiming at the defect of self-adaptability in normal digital watermarking algorithm of DCT domain, proposed an encrypted and adaptive digital watermarking algorithm using Arnold and DCT transformation. Transformed the watermarking by Arnold transformation before being embedded. On the one hand, it reduced the relativity among watermarking data. On the other hand, it also hugely increased the security of watermarking through dealing with watermarking data. Embedded some DCT coefficients in watermarking by JPEG matrix. It dynamically and adaptively adjusted the embedded intensity, which made it have a good effect in embedding .At the same time, it ensured the concealed character of watermarking. The experiment shows that the proposed algorithm has very strong robustness for some common image processing operations such as median filtering, Gauss noise, salt-pepper noise and JPEG compression, etc attack.
Study of the effect DCT and DWT domains on the imperceptibility and robustness of Genetic watermarking
Abduljabbar Shaamala,Shahidan M. Abdullah,Azizah A. Manaf
International Journal of Computer Science Issues , 2011,
Abstract: Watermarking using genetic algorithm for the optimization of the tread-off between the watermarking requirements has attacked the attention of researchers; amongst the watermarking requirements, the imperceptibility and robustness is the main requirements. Watermarking embedded in frequency domain using DWT or DCT can affect the imperceptibility and robustness of watermarking, this paper studies the effect of embedding domain on the imperceptibility and robustness in genetic watermarking. Results of watermark image quality and attacks based on peak signal-to-noise ratio (PSNR) numerical correlation (NC) is analyzed through the paper sections, the DWT results showed more robustness high imperceptibility than DCT in watermarking based on GA.
A New Method For Digital Watermarking Based on Combination of DCT and PCA  [PDF]
Arash Saboori,S. Abolfazl Hosseini
Computer Science , 2015, DOI: 10.1109/TELFOR.2014.7034461
Abstract: In the digital watermarking with DCT method,the watermark is located within a range of DCT coefficients of the cover image. In this paper to use the low-frequency band, a new method is proposed by using a combination of the DCT and PCA transform. The proposed method is compared to other DCT methods, our method is robust and keeps the quality of cover image, also increases capacity of the watermarking.
SURVEY OF DIGITAL WATERMARKING USING DCT
Usha Pal,Dinesh Chandra
International Journal on Computer Science and Engineering , 2012,
Abstract: Digital Watermarking is not a new name in the technology world but there are many new issues arise related with watermark. This paper surveys recent advances in watermarking techniques in digital images. The aim of digital watermarking is hidden information added into content of multimedia. In this paper, DCT technique is used and when size of image is increase then also increases PSNR without decreasing power of embedded factor[1] (alpha factor) in same format.
Adaptive audio watermarking algorithm in DCT domain
一种DCT域自适应音频水印算法*

HUANG Xiong-hu,WANG Hong-xia,
黄雄华
,王宏霞

计算机应用研究 , 2009,
Abstract: The watermarking strength in digital watermarking technology is an important parameter affecting the robustness.Most of watermarking algorithms nowadays make use of experiment to obtain certain the watermarking strength.The results of experiment will be random.So,a lot of experiments have to be done in order to obtain appropriate strength factor.This paper proposed an adaptive audio watermarking strength based on SNR in DCT(discrete cosine transform)domain.Firstly,divided carrier audio into some frames,and ...
太行山平山、正定、盂?地?前寒武???岩系现?????  [PDF]
地质学报 , 1961,
Abstract: 为了进一步解决太行山一带前寒武纪变质岩系地层的划分等问题,本年六月十五日至廿四日,由山西省地质厅王植总工程师负责主持召集有关单位代表在河北省正定县陈庄、南寺,平山县东回舍,山西省盂县会理一带进行了现埸观察和讨论。
Research on Blind Watermarking Embedding Algorithm with Replacing Middle Frequency Coefficients in DCT Domain
置换DCT域中频系数的盲水印嵌入算法研究*

FU Wei,XING Guang-zhong,
付炜
,邢广忠

计算机应用研究 , 2007,
Abstract: This paper proposed a blind watermarking algorithm based on replacing the middle frequency coefficients in DCT domain,and researched the self-adaptive embedding method of digital watermarking by employing the algorithm.This algorithm pierced into the traditional watermarking embedding algorithms,such as additive algorithm and multiplicative algorithm,which solved the problem that the detection accuracy becomes lower because the DCT coefficients of the original image exist in the extracted watermark.Moreover,the watermark was self-adaptively embedded in image using HVS,and the embedded digital watermarking is not inverse radically.The experiments prove the strong robustness against the attacks such as filtering,cropping and adding noise.
Relational database watermarking algorithm based on chaos and DCT
基于混沌的DCT域关系数据库水印算法*

ZHOU Fei,ZHAO Huai-xun,
周飞
,赵怀勋

计算机应用研究 , 2012,
Abstract: This paper presented a relational database robust watermarking algorithm based on chaos and DCT,which took the advantage of the frequency domain approach of multimedia digital watermarking into the area of relational database watermar-king.By DCT on grouped and sorted tuples and modifying some of the transformed frequency coefficients to embed image watermark,only affecting one attribute for each tuple,the algorithm had good watermarking invisibility.Pseudo-random,sensitive to initial value of chaotic sequences improved the security of the watermark.The extraction did not need the original data.The experimental results show that the algorithm possesses strong robustness and good invisibility.
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