RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제
      • 좁혀본 항목 보기순서

        • 원문유무
        • 원문제공처
          펼치기
        • 등재정보
          펼치기
        • 학술지명
          펼치기
        • 주제분류
          펼치기
        • 발행연도
          펼치기
        • 작성언어
        • 저자
          펼치기

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • A Dynamic Gesture Trajectory Recognition Based on Key Frame Extraction and HMM

        Zhang Qiu-yu,Lv Lu,Zhang Mo-yi,Duan Hong-xiang,Lu Jun-chi 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.6

        Aiming at changing high computational complexity, underdeveloped real time, low recognition rate of dynamic gesture recognition algorithms, this paper present a real-time dynamic gesture trajectory recognition method based on key frame extraction and HMM. Key frames are selected without keeping track of all the details of one dynamic gesture, which is based on difference degree between frames. The trajectory data stream, sorted by the time-warping algorithm, is used to construct the Hidden Markov Method model of dynamic gesture. Finally, optimal transition probabilities are employed to implement dynamic gesture recognition. The result of this experiment implies that this method has high robustness and real time. The average recognition rate of dynamic gesture (0~9) is up to 87.67%, and average time efficiency is 0.46s.

      • Hand Gesture Segmentation Method Based on YCbCr Color Space and K-Means Clustering

        Zhang Qiu-yu,Lu Jun-chi,Zhang Mo-yi,Duan Hong-xiang,Lv Lu 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.5

        Aiming at the problems that current skin-color detection segmentation technologies have unsatisfied segmentation results under conditions of complex illumination or backgrounds, we present a new method based on YCbCr color space and K-means clustering algorithm for segmentation hand gesture. Firstly, image in RGB color space is converted to YCbCr color space; and then YCbCr color space of image is divided into luminance Y and chrominance Cb and Cr. Lastly, the binary image is achieved by clustering values of chrominance using k-means clustering algorithm, and hand gesture segmentation is completed by conducting morphological process of binary image obtained. The experimental results illustrate that the proposed method can segment hand gestures from complex backgrounds and obtain segmentation results. The phenomena of similar skin color interference and skin color overlapping are solved with this method effectively. In addition, it is robust to illumination condition.

      • KCI등재

        Gadolinium- and lead-containing functional terpolymers for low energy X-ray protection

        Yu-Juan Zhang,Xin-Tao Guo,Chun-Hong Wang,Xiang An Lu,De-Feng Wu,Ming Zhang 한국원자력학회 2021 Nuclear Engineering and Technology Vol.53 No.12

        By polymerization of gadolinium methacrylate (Gd (MAA)3), lead methacrylate (Pb(MAA)2) and methylmethacrylate (MMA), Gd and Pb were chemically bonded into polymers. The X-ray shielding performance was evaluated by Monte Carlo simulation method, and the results showed that the more metalfunctional organic monomer, the better the shielding performance of terpolymers. When the X-rayenergy is 65 keV, Gd (MAA)3-containing polymers have better shielding performance than Pb(MAA)2-containing polymers. Gd could compensate for the weak absorption region of Pb. Therefore, polymerscontaining both Gd and Pb enhanced shielding efficiency against X-ray in various low-energy ranges. Forobtaining terpolymers with uniform monomer compositions, the relationship between the monomercomposition of the terpolymers and the conversion level was optimized by calculating the reactivityratios. The value of reactivity ratios of r (Gd (MAA)3/Pb(MAA)2), r (Pb(MAA)2/Gd (MAA)3), r (Gd (MAA)3/MMA), r (MMA/Gd (MAA)3), r (Pb(MAA)2/MMA) and r (MMA/Pb(MAA)2) was 0.483, 0.004, 0.338, 2.508,0.255, 0.029. The terpolymers with uniform monomer composition could be obtained by controlling themonomer compositions or conversion levels. The results can provide new radiation protection materialsand contribute to the improvement in nuclear safety.

      • Risk Factors for Cervical Cancer in Rural Areas of Wuhan China: a Matched Case-control Study

        Zhang, Bin,Zhou, Ai-Fen,Zhu, Chang-Cai,Zhang, Ling,Xiang, Bing,Chen, Zhong,Hu, Rong-Hua,Zhang, Ya-Qi,Qiu, Lin,Zhang, Yi-Ming,Xiong, Chao-Du,Du, Yu-Kai,Shi, Yu-Qin Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.12

        Cervical cancer is a serious public health problem in developing countries. We investigated possible risk factors for cervical cancer in rural areas of Wuhan China using a matched case-control study with 33 women diagnosed with cervical cancer and 132 healthy women selected from the same area as matched controls. A questionnaire, which included questions about general demography conditions, environmental and genetic factors, the first sexual intercourse, first marriage age, age at first pregnancy, pregnancy first child's age, female personal health history, social psychological factors, dietary habits, smoking and alcohol status and other living habits was presented to all participants. At the same time, HPV infection of every participant was examined in laboratory testing. Results showed HPV infection (P<0.000, OR=23.4) and pregnancy first child's age (P<0.000, OR=13.1) to be risk factors for cervical cancer. Menopause (P=0.003, OR=0.073) was a protective factor against cervical cancer. However, there was no indication of associations of environmental (drinking water, insecticide, disinfectant) genetic (cancer family history), or life-style factors (smoking status, alcohol status, physical training, sleep quality), including dietary habits (intake of fruit and vegetable, meat, fried food, bean products and pickled food) or social psychological factors with cervical cancer. The results suggest that the risk of cervical cancer in Chinese rural women may be associated with HPV infection, menopause and the pregnancy first child's age.

      • Dynamic Hand Gesture Segmentation Method Based on Improved Kalman Filter and Weighted Skin-Color Model

        Zhang Qiu-yu,Lu Jun-chi,Wei Hui-yi,Zhang Mo-yi,Duan Hong-xiang 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.6

        In order to improve the problems of segmentation accuracy and real-time existing in dynamic hand gesture under complex backgrounds, this paper presents a kind of dynamic hand gesture segmentation method based on improved Kalman filter and weighted skin-color model. Firstly, improved Kalman filter is utilized to process hand gesture image of hand gesture video sequences and get rough hand gesture results. Secondly, weighted skin-color model is applied to process rough results of hand gesture segmentation and segment hand gesture. Finally, morphological method is utilized to deal with gesture segmentation result, getting rid of the holes in the hand gesture’s binary image to realize the segmentation of dynamic hand gesture. Experiments show that the proposed method can segment hand gesture from dynamic hand gesture video sequences with complex backgrounds effectively. And the accuracy of hand gesture segmentation is high.

      • KCI등재

        A New Quorum-Sensing Inhibitor Attenuates Virulence and Decreases Antibiotic Resistance in Pseudomonas aeruginosa

        Yu-Xiang Yang,Zhen-Hua Xu,Yu-Qian Zhang,Jing Tian,Li-Xing Weng,Lian-Hui Wang 한국미생물학회 2012 The journal of microbiology Vol.50 No.6

        Quorum sensing (QS) has been a novel target for the treatment of infectious diseases. Here structural analogs of Pseudomonas aeruginosa autoinducer N-acyl homoserine lactone (AHL) were investigated for QS inhibitor (QSI) activity and a novel QSI was discovered, N-decanoyl-L-homoserine benzyl ester (C2). Virulence assays showed that C2 downregulated total protease and elastase activities, as well as the production of rhamnolipid, that are controlled by QS in P.aeruginosa wild-type strain PAO1 without affecting growth. C2 was also shown to inhibit swarming motility of PAO1. Using a microdilution checkerboard method, we identified synergistic interactions between C2 and several antibiotics, tobramycin, gentamycin, cefepime, and meropenem. Data from real-time RT-PCR suggested that C2 inhibited the expression of lasR (29.67%), lasI (21.57%), rhlR (28.20%), and rhlI (29.03%).

      • The catalytic core of DEMETER guides active DNA demethylation in <i>Arabidopsis</i>

        Zhang, Changqing,Hung, Yu-Hung,Rim, Hyun Jung,Zhang, Dapeng,Frost, Jennifer M.,Shin, Hosub,Jang, Hosung,Liu, Fang,Xiao, Wenyan,Iyer, Lakshminarayan M.,Aravind, L.,Zhang, Xiang-Qian,Fischer, Robert L. National Academy of Sciences 2019 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.116 No.35

        <P><B>Significance</B></P><P>Flowering plants reproduce via a unique double-fertilization event, producing the zygote and the nutritive endosperm. The genome of the central cell, the precursor of the endosperm, undergoes extensive demethylation prior to fertilization. This epigenetic reconfiguration, directed by the DEMETER (DME) glycosylase at thousands of loci in <I>Arabidopsis</I>, differentiates the epigenetic landscapes of parental genomes and establishes parent of origin-specific expression of many imprinted genes in endosperm essential for seed development. However, how DME is targeted to various locations remains unknown. Here we show that the multidomain DME is organized into 2 functional regions: the C-terminal region, which guides localization and catalysis, and the N-terminal region, which likely recruits chromatin remodelers to facilitate demethylation within heterochromatin.</P><P>The <I>Arabidopsis</I> DEMETER (DME) DNA glycosylase demethylates the maternal genome in the central cell prior to fertilization and is essential for seed viability. DME preferentially targets small transposons that flank coding genes, influencing their expression and initiating plant gene imprinting. DME also targets intergenic and heterochromatic regions, but how it is recruited to these differing chromatin landscapes is unknown. The C-terminal half of DME consists of 3 conserved regions required for catalysis in vitro. We show that this catalytic core guides active demethylation at endogenous targets, rescuing <I>dme</I> developmental and genomic hypermethylation phenotypes. However, without the N terminus, heterochromatin demethylation is significantly impeded, and abundant CG-methylated genic sequences are ectopically demethylated. Comparative analysis revealed that the conserved DME N-terminal domains are present only in flowering plants, whereas the domain architecture of DME-like proteins in nonvascular plants mainly resembles the catalytic core, suggesting that it might represent the ancestral form of the 5mC DNA glycosylase found in plant lineages. We propose a bipartite model for DME protein action and suggest that the DME N terminus was acquired late during land plant evolution to improve specificity and facilitate demethylation at heterochromatin targets.</P>

      • Dynamic Hand Gesture Trajectory Recognition Based on Block Feature and Skin-Color Clustering

        Zhang Qiu-yu,Lv Lu,Lu Jun-chi,Zhang Mo-yi,Duan Hong-xiang 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.12

        In recent years, dynamic hand gesture recognition has been a research hotspot of human-computer interaction. Since most existing algorithms contain problems with high computational complexity, poor real-time performance and low recognition rate, which cannot satisfy the need of many practical applications. Moreover, key frames obtained by inter-frame difference degree algorithm contain less information, which leads to less identified species and lower recognition rate. To solve these problems, we present a dynamic hand gesture trajectory recognition method based on the theory of block feature to extract key frames and the skin-color clustering’s hand gesture segmentation. Firstly, this method extracts block feature of degree of difference between frames in hand gesture sequence to select key frames accurately. Secondly, the method based on skin-color clustering is applied to obtain the area of hand gesture after segmenting hand gestures from images. Finally, hidden Markov model (HMM), in which the angle data of hand gesture trajectories are input, is used for modeling and identifying dynamic hand gestures. Experimental results show that the method of key-frame extraction is used to obtain information of dynamic hand gestures accurately, which would improve the recognition rate of dynamic hand gesture recognition and, at the same time, can guarantee the real-time of hand gesture recognition system. The average recognition rate is up to 86.67%, and the average time efficiency is 0.39s.

      • Treatment Efficacy and Prognostic Factors for Huge HCC Based on Barcelona Clinic Liver Cancer Staging

        Zhang, Zhi-Ming,Zhang, Yu-Mei,Gao, Sheng,Yuan, Wei-Ping,Zhao, Yin-Nong,Xiang, Bang-De,Wu, Fei-Xiang,Wu, Guo-Bin,Liu, Jian-Yong Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.20

        Objective: To explore the most appropriate treatment for patients with hepatocellular cancer (HCC) >10 cm by using the Barcelona Clinic Liver Cancer (BCLC) classification. Materials and Methods: A total of 124 HCC patients undergoing surgery were selected. Disease-free survival (DFS), overall survival (OS) and prognostic factors were respectively assessed. Results: This study showed that the cumulative 1-, 3-, 5-year survival rates were 79.7%, 59.8% and 41.6% in BCLC-A patients, 76.2%, 9.5% and 0% in BCLC-B patients and 44.9%, 0% and 0% in BCLC-C patients, respectively. The 1-, 3-, 5-year DFS rates were 49%, 24.5% and 9.1% in BCLC-A patients, 7.5%, 0% and 0% in BCLC-B patients, respectively. No BCLC-C patients survived 1 year after surgery. Multivariate analysis indicated that hepatitis B surface antigen (HBsAg), vascular invasion, intra-hepatic metastasis, curative resection, tumor rupture and pathologic differentiation were independent prognostic factors. Conclusions: Surgery is effective and safe for patients with HCC >10 cm with sufficient hepatic reserve.

      • KCI등재

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼