Forensics Aided Steganalysis of Heterogeneous Bitmap Images with Different Compression History

( Xiaodan Hou ),( Tao Zhang ),( Gang Xiong ),( Baoji Wan ) 한국인터넷정보학회 2012 KSII Transactions on Internet and Information Syst Vol.6 No.8

In this paper, two practical forensics aided steganalyzers (FA-steganalyzer) for heterogeneous bitmap images are constructed, which can properly handle steganalysis problems for mixed image sources consisting of raw uncompressed images and JPEG decompressed images with different quality factors. The first FA-steganalyzer consists of a JPEG decompressed image identifier followed by two corresponding steganalyzers, one of which is used to deal with uncompressed images and the other is used for mixed JPEG decompressed images with different quality factors. In the second FA-steganalyzer scheme, we further estimate the quality factors for JPEG decompressed images, and then steganalyzers trained on the corresponding quality factors are used. Extensive experimental results show that the proposed two FA-steganalyzers outperform the existing steganalyzer that is trained on a mixed dataset. Additionally, in our proposed FA-steganalyzer scheme, we can select the steganalysis methods specially designed for raw uncompressed images and JPEG decompressed images respectively, which can achieve much more reliable detection accuracy than adopting the identical steganalysis method regardless of the type of cover source.

한·중 대량(大量) 표현 ‘많다/많이’와 ‘多’의 대응 연구

후효단(Hou, Xiaodan),김현철(Kim, Hyun-Cheol),최송호(Cui, Songhu) 한국외국어교육학회 2017 Foreign languages education Vol.24 No.2

Manhta/manhi’ and ‘duo’ are common expressions that can be used to express large quantity in Korean and Chinese, respectively. By conducting a comparative study on ‘manhta/manhi’ in Korean and ‘duo’ in Chinese, this article comes to a conclusion on different conditions where there are correspondence and non-correspondence concerning the constructions that include ‘manhta/manhi’ and ‘duo’. The constructions that include ‘manhta/manhi,’ ‘duo’ and verbs are (1) ‘manhi+transitive verbs’, ‘transitive verbs+duo’ and ‘duo+transitive verbs’; (2) ‘manhi+intransitive verbs’, ‘intransitive verbs+duo’ and ‘manhi+intransitive verbs’. The constructions that include ‘manhta’, ‘duo’ and nouns are (1) ‘nouns+manhta’ and ‘nouns+duo’; (2) ‘manhun+nouns’ and ‘duo+nouns’. By scrutinizing the constructions that include ‘duo’, ‘manhta’ and numeral and quantifier, and adjectives or adverbs according to their syntactic orders, the correspondence and non-correspondence between these constructions are summarized. In conclusion, this paper attempts to contribute to teaching and learning Korean for Chinese students, as well as teaching and learning Chinese for Koreans. ‘manhta(形容詞)/manhi(副詞)’和‘多’是韩汉语中典型的大量表达。和他动词连用时形成‘manhi+他动词’、‘多+他动词’和‘他动词+多’结構,和自动词连用时形成‘manhi+自动词、‘多+自动词’和‘自动词+多’结構。和名词表达连用时,形成了‘名词表达+多’、‘名词表达+manhta’、‘多+名词表达’和‘manhun+名词表达’的结構。和数词與量词及形容词或副词表达连用时,根据‘多’的使用位置不同可構成多種结構。本文分析了‘多’和‘manhta/manhi’在这些结構中的对应情况,並且拟通过此对比研究,对第二语言的学习和教学有所幫助。

개념 공간 이론으로 본 한국어 ‘아무’ 계열과 중국어 ‘任何’ 계열의 특징 연구

侯曉丹(Hou Xiaodan),金基石(Jin Jishi) 중국어문학연구회 2016 중국어문학논집 Vol.0 No.99

Based on the conceptual space of indefinite pronouns proposed by Haspelmath, this paper systematically organizes the various structures of the ‘任何’ set in Chinese and the ‘아무’ set in Korean, concludes their functions in the conceptual space, and makes the semantic map, through which similarities and differences of those functions can be visually compared. By analyzing the respective function semantics of the two sets of ‘任何’ and ‘아무’, the paper is based on the similarities and differences of semantics and explores the semantic contact between these functions so as to make a comparison on semantics of the ‘任何’ set and the ‘아무’ one. Moreover, on the basis of the comparative analysis of Chinese and Korean, this paper questions the conceptual space of indefinite pronouns raised by Haspelmath and makes a tentative revision on it.

한 중소량표현‘조금’과‘一點兒’의대응양상연구

侯?丹(Hou Xiaodan),金鉉哲(Kim, Hyun-cheol) 중국어문학연구회 2017 중국어문학논집 Vol.0 No.103

Both “jogeum” and “一點兒” are common expressions that can be used to express small quantity in Korean and Chinese. By making an analytic and comparative study on “jogeum” and “一點兒” when they are used together with verbs, nouns, adjectives, adverbs and other expressions, this article comes to a conclusion on different conditions (1) where there are correspondences for these expressions in Chinese and Korean and (2) where there is no parallelism concerning the phrase meaning “small quantity” in both languages. The constructions which include “jogeum”, “一點兒” and verbs are (1) “objects+jogeum+transitive verbs” and “transitive verbs+一點兒+objects”,(2) “jogeum+intransitive verbs” and “intransitive verbs+一點兒”. And the constructions which include “jogeum”, “一點兒” and nouns are (1) “jogeum+의+nouns” and “一點兒(+ 的)+nouns”, (2) “jogeum+nouns” and “一點兒+nouns”,(3) “nouns+jogeum” and “nouns + 一點兒”. With a focus on sentence meaning, this article analyzes the similarities and differences in the usage of small quantity expressions in these constructions when they occur with expressions of physical quantity, substance amount, spatial quantity, time capacity, the amounts of behavior and degrees. The constructions which include “jogeum”, “一點兒” and adjectives are “jogeum+adjectives” and “adjectives+一點兒”, The constructions which include “jogeum”, “一點兒” and adverbs are “jogeum+adverbs”, “adverbs+jogeum” and “adjectives +一點兒”. This article analyzes the similarities and differences in the usage of the small quantity expressions in these constructions according to the meaning of sentences. In sum, this paper attempts to make a contribution to teaching and learning of Korean for Chinese students, as well as teaching and learning of Chinese for Koreans.

Reduction of Graphene Oxide and its Effect on Square Resistance of Reduced Graphene Oxide Films

Zhaoxia Hou,Yin Zhou,Guangbin Li,Shaohong Wang,Meihan Wang,Xiaodan Hu,Siming Li 대한화학회 2015 Bulletin of the Korean Chemical Society Vol.36 No.6

Graphite oxide was prepared via the modified Hummers’ method and graphene via chemical reduction. Deoxygenation efficiency of graphene oxide was compared among single reductants including sodium borohydride, hydrohalic acids, hydrazine hydrate, and vitamin C. Two-step reduction of graphene oxide was primarily studied. The reduced graphene oxide was characterized by XRD, TG, SEM, XPS, and Raman spectroscopy. Square resistance was measured as well. Results showed that films with single-step N2H4 reduction have the best transmittance and electrical conductivity with square resistance of ~5746 Ω/sq at 70% transmittance. This provided an experimental basis of using graphene for electronic device applications.

Dynamic Changes of Transcriptome and Metabolites During Ripening of Alpinia Oxyphylla Fruit (AOF)

Pan Kun,Yu Xiaodan,Wang Shujuan,Hou Jie,Luo Yuchao,Gao Bingmiao 한국식물학회 2022 Journal of Plant Biology Vol.65 No.6

Alpinia oxyphylla (Yizhi) is an economically valuable plant, not only used as edible fruit, but also as an important traditional medicinal material. However, there are few studies on fruit development and metabolic pathways. To elucidate the dynamic changes of metabolites and transcription levels during fruit development of A. oxyphylla, the four parts of A. oxyphylla fruit from different periods, including early fruit (EF), middle fruit (MF), late pericarp (LP) and late seed (LS) were collected. KEGG pathway analysis shows that DEGs in EF, MF, LP are involved in amino sugar and nucleotide sugar metabolism, starch and sucrose metabolism, and plant hormone signal transduction. However, at the late part of fruit development (LS), most of the DEGs between LS and LP were enriched in pyruvate metabolism, glycolysis/gluconeogenesis, tryptophan metabolism. We found that in the early and middle parts of fruit development (EF, MF), many differential metabolites were enriched in piperidine tropane and biosynthesis of secondary metabolites, pyridine alkaloid biosynthesis. In addition, important active components, such as nootkatone in A. oxyphylla fruits accumulated in the LS part, but did not show significant differences in the first three parts. Some key transcription factors that are significantly positively correlated with the maturation of AOF have also been identified. Together, our research provides new insights into the accumulation of metabolites and the dynamic changes of the transcriptome during fruit development.

New Blind Steganalysis Framework Combining Image Retrieval and Outlier Detection

( Yunda Wu ),( Tao Zhang ),( Xiaodan Hou ),( Chen Xu ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.12

The detection accuracy of steganalysis depends on many factors, including the embedding algorithm, the payload size, the steganalysis feature space and the properties of the cover source. In practice, the cover source mismatch (CSM) problem has been recognized as the single most important factor negatively affecting the performance. To address this problem, we propose a new framework for blind, universal steganalysis which uses traditional steganalyst features. Firstly, cover images with the same statistical properties are searched from a reference image database as aided samples. The test image and its aided samples form a whole test set. Then, by assuming that most of the aided samples are innocent, we conduct outlier detection on the test set to judge the test image as cover or stego. In this way, the framework has removed the need for training. Hence, it does not suffer from cover source mismatch. Because it performs anomaly detection rather than classification, this method is totally unsupervised. The results in our study show that this framework works superior than one-class support vector machine and the outlier detector without considering the image retrieval process.

New Blind Steganalysis Framework Combining Image Retrieval and Outlier Detection

Wu, Yunda,Zhang, Tao,Hou, Xiaodan,Xu, Chen Korean Society for Internet Information 2016 KSII Transactions on Internet and Information Syst Vol.10 No.12

The detection accuracy of steganalysis depends on many factors, including the embedding algorithm, the payload size, the steganalysis feature space and the properties of the cover source. In practice, the cover source mismatch (CSM) problem has been recognized as the single most important factor negatively affecting the performance. To address this problem, we propose a new framework for blind, universal steganalysis which uses traditional steganalyst features. Firstly, cover images with the same statistical properties are searched from a reference image database as aided samples. The test image and its aided samples form a whole test set. Then, by assuming that most of the aided samples are innocent, we conduct outlier detection on the test set to judge the test image as cover or stego. In this way, the framework has removed the need for training. Hence, it does not suffer from cover source mismatch. Because it performs anomaly detection rather than classification, this method is totally unsupervised. The results in our study show that this framework works superior than one-class support vector machine and the outlier detector without considering the image retrieval process.