A New Reference Pixel Prediction for Reversible Data Hiding with Reduced Location Map

( Jeanne Chen ),( Tung-shou Chen ),( Wien Hong ),( Gwoboa Horng ),( Han-yan Wu ),( Chih-wei Shiu ) 한국인터넷정보학회 2014 KSII Transactions on Internet and Information Syst Vol.8 No.3

In this paper, a new reversible data hiding method based on a dual binary tree of embedding levels is proposed. Four neighborhood pixels in the upper, below, left and right of each pixel are used as reference pixels to estimate local complexity for deciding embeddable and non-embeddable pixels. The proposed method does not need to record pixels that might cause underflow, overflow or unsuitable for embedment. This can reduce the size of location map and release more space for payload. Experimental results show that the proposed method is more effective in increasing payload and improving image quality than some recently proposed methods.

Robotic Curved Surface Tracking with a Neural Network for Angle Identification and Constant Force Control based on Reinforcement Learning

Tie Zhang,Meng Xiao,Yan-biao Zou,Jia-dong Xiao,Shou-yan Chen 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.21 No.5

Aiming to solve the problem that the contact force at a robot end eff ector when tracking an unknown curved-surface workpieceis diffi cult to keep constant, a robot force control algorithm based on reinforcement learning is proposed. In this paper,a contact model and force mapping relationship are established for a robot end eff ector and surface. For the problem thatthe tangential angle of the workpiece surface is diffi cult to obtain in the mapping relationship, a neural network is used toidentify the tangential angle of the unknown curved-surface workpiece. To keep the normal force of the robot end eff ectorconstant, a compensation term is added to a traditional explicit force controller to adapt to the robot constant force trackingscenario. For the problem that the compensation term parameters are diffi cult to select, the reinforcement learning algorithmA2C (advantage actor critic) is used to fi nd the optimal parameters, and the return function and state values are modifi edin the A2C algorithm to satisfy the robot tracking scenario. The results show that the neural network algorithm has a goodrecognition eff ect on the tangential angle of the curved surface. The force error between the normal force and the expectedforce is substantially within ± 2 N after 60 iterations of the robot force control algorithm based on A2C; additionally, thevariance of the force error decreases by 50.7%, 34.05% and 79.41%, respectively, compared with the force signals obtainedby a fuzzy iterative algorithm and an explicit force control with two sets of fi xed control parameters.

Effects of IFN-γ on IL-18 Expression in Pregnant Rats and Pregnancy Outcomes

Si, Li-Fang,Zhang, Shou-Yan,Gao, Chun-Sheng,Chen, Shu-Lin,Zhao, Jin,Cheng, Xiang-Chao Asian Australasian Association of Animal Productio 2013 Animal Bioscience Vol.26 No.10

The present study focused on establishing the effects of interferon-gamma (IFN-${\gamma}$) on interleukin-18 (IL-18) expression patterns and pregnancy outcomes in pregnant rats. Pregnant rats at the post-implantation stage were randomized into control, low IFN-${\gamma}$ (L-IFN-${\gamma}$) and high IFN-${\gamma}$ groups (H-IFN-${\gamma}$) that received normal saline, 100 IU/g of IFN-${\gamma}$ and 500 IU/g of IFN-${\gamma}$ vaginal muscular injection, respectively. The effects of IFN-${\gamma}$ on IL-18 expression and pregnancy outcomes were assessed systematically using several methods, including immunohistochemistry streptavidin-perosidase (SP), image pattern analysis, enzyme-linked immune-sorbent assay (ELISA), whole blood count (WBC) count, microscopy and visual observation. IL-18 was detected in the uteri of all pregnant rats, and mainly distributed in the endometrium, decidual cells, vascular endothelium and myometrium. Immunohistochemistry and image pattern analyses revealed significantly lower IL-18 expression in the H-IFN-${\gamma}$ group compared to the L-IFN-${\gamma}$ and control groups (p<0.01), indicating that high doses of IFN-${\gamma}$ induce downregulation of IL-18 in the uterus of pregnant rats. ELISA results disclosed that IL-18 expression in peripheral blood of the H-IFN-${\gamma}$ group was lower than that of the L-IFN-${\gamma}$ group (p<0.05), and significantly reduced compared to the control group (p<0.01). Moreover, the number of peripheral leukocytes in the H-IFN-${\gamma}$ group was significantly higher than those in the control and L-IFN-${\gamma}$ groups (p<0.01). Morphology analysis showed no evident differences between the L-IFN-${\gamma}$ and control groups. However, for the H-IFN-${\gamma}$ group, uterine mucosa bleeding, necrosis and excoriation were observed using microscopy. Visual observation revealed marroon, swelling, crassitude and no embryo in the uterus, which are obvious indicators of abortion. These results indicate that IFN-${\gamma}$ plays a regulatory role in IL-18 expression in the uterus and peripheral blood of pregnant rats at the post-implantation stage. Moreover, high levels (500 IU/g) of IFN-${\gamma}$ influence normal pregnancy at the early stages in rats by downregulating IL-18 expression in the uterus and peripheral blood and increasing the number of peripheral leukocytes, consequently triggering termination of pregnancy.

Clinical Significance of Upregulation of mir-196a-5p in Gastric Cancer and Enriched KEGG Pathway Analysis of Target Genes

Li, Hai-Long,Xie, Shou-Pin,Yang, Ya-Li,Cheng, Ying-Xia,Zhang, Ying,Wang, Jing,Wang, Yong,Liu, Da-Long,Chen, Zhao-Feng,Zhou, Yong-Ning,Wu, Hong-Yan Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.5

Background: miRNAs are relatively recently discovered cancer biomarkers which have important implications for cancer early diagnosis, treatment and estimation of prognosis. Here we focussed on expression of mir-196a-5p in gastric cancer tissues and cell lines so as to analyse its significance for clinicopathologic characteristics and generate enriched KEGG pathways clustered by target genes for exploring its potential roles as a biomarker in gastric cancer. Materials and Methods: The expression of mir-196a-5p in poorly, moderate and well differentiated gastric cancer cell lines compared with GES-1 was detected by RT-qPCR, and the expression of mir-196a-5p in gastric cancer tissues comparing with adjacent non cancer tissues of 58 cases were also assessed by RT-qPCR. Subsequently, an analysis of clinical significance of mir-196a-5p in gastric cancer and enriched KEGG pathways was executed based on the miRWalk prediction database combined with bioinformatics tools DAVID 6.7 and Mirfocus 3.0. Results: RT-qPCR showed that mir-196a-5p was up-regulated in 6 poorly and moderate differentiated gastric cancer cell lines SGC-7901, MKN-45, MKN-28, MGC-803, BGC-823, HGC-27 compared with GES-1, but down-regulated in the highly differentiated gastric cancer cell line AGS. Clinical data indicated mir-196a-5p to beup-regulated in gastric cancer tissues (47/58). Overexpression of mir-196a-5p was associated with more extensive degree of lymph node metastasis and clinical stage (P < 0.05; x2 test). Enriched KEGG pathway analyses of predicted and validated targets in miRWalk combined with DAVID 6.7 and Mirfocus 3.0 showed that the targeted genes regulated by mir-196a-5p were involved in malignancy associated biology. Conclusions: Overexpression of mir-196a-5p is associated with lymph node metastasis and clinical stage, and enriched KEGG pathway analyses showed that targeted genes regulated by mir-196a-5p may contribute to tumorgenesis, suggesting roles as an oncogenic miRNA biomarker in gastric cancer.

Application of Computed Tomography for Differential Diagnosis of Glioma Stoke and Simple Cerebral Hemorrhage

Li, Xiao-Li,Zhou, Fa-Ming,Shangguan, Shou-Qin,Zou, Wen-Qin,Deng, Yan-Qing,Chen, Tao,Chen, Guang-Hui Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.8

Objective: To explore the value of computed tomography (CT) in the differential diagnosis of glioma stroke and simple cerebral hemorrhage. Materials and Methods: A total of 45 patients with glioma stroke and stroke as the initial symptom in our hospital from Jun., 2009 to Oct., 2013 were selected along with 50 individuals with simple cerebral hemorrhage in the same period randomly collected as a control group. The CT results in both groups were analyzed and compared. Results: In the observation group, there were 25 patients with astrocytoma (55.6%), 11 with oligodendroglioma (24.4%), 8 with ependymoma (17.2%) and 1 with glioblastoma multiforma (GBM, 2.22%). Additionally, the major CT manifestation was coexistence of hemorrhage and tumor signs. By comparison, it could be found that the proportions of patients respectively with peripheral edema and space-occupying effect in the observation group were significantly higher than in the control group (P<0.01). Conclusions: Application of CT examination combined with medical history in patients has very important clinical value in the differential diagnosis of glioma stroke and simple cerebral hemorrhage.

Robot Grinding System Trajectory Compensation Based on Co-Kriging Method and Constant-Force Control Based on Adaptive Iterative Algorithm

Tie Zhang,Ye Yu,Li-xin Yang,Meng Xiao,Shou-yan Chen 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.21 No.9

To reduce the grinding trajectory deviation caused by the absolute positioning accuracy of robot, a trajectory compensation method based on Co-Kriging space interpolation method is proposed. Meanwhile, an adaptive iterative constant force control method based on one-dimensional force sensor is proposed to improve the processing quality and efficiency of robot belt grinding. Firstly, an error model based on 6 DOF robot is constructed. Then, considering the workspace of robot belt grinding and the similarity of robot position error, the Co-Kriging compensation algorithm is used to compensate the grinding trajectory, which makes the compensation process convenient and accurate. Then, a grinding dynamics model based on deformation is established, and an adaptive iterative constant force control is proposed for complex robot belt grinding process, which overcomes the instability of grinding force and shortens its convergence time. Finally, the grinding trajectory compensation experiment and the force control experiment of spherical workpiece are carried out. The results show that the space interpolation compensation algorithm based on Co-Kriging method can significantly improve both the space position error of grinding trajectory and the actual error of workpiece, which proves the feasibility of compensation algorithm. Through force control algorithm, the grinding force fluctuation is maintained within 2 N, the mean value, standard deviation and variance of absolute value of force error are significantly reduced, the convergence rate of grinding force and the roughness of workpiece are much better than before, which shows the effectiveness of the proposed force control algorithm.