TTKC : A Taylor Triangle K Coverage Algorithm in WSNs

Xiaohui Ji,Jie Xie,Yuanbo Li 보안공학연구지원센터 2016 International Journal of Future Generation Communi Vol.9 No.6

A Complex Network Structure Evaluation Model Based on Cloud Computing

Xiaohui Ji,Jie Xie 보안공학연구지원센터 2016 International Journal of Grid and Distributed Comp Vol.9 No.6

Cloud systems are difficult to assess due to the relevance of modeling and its large-scale, complex structure, highlighting the dynamic and powerful layer. To solve this problem, the cloud system evaluation model is proposed based on queuing Petri network. It can efficiently model and simulate complex cloud system due to its powerful combination of quantitative evaluation and behavior description of the theoretical characteristics of queuing theory and Petri nets. On the basis of the model, we further increase the quantitative analysis and evaluation system cloud systems, and simulation of cloud systems, massively parallel dynamic service environments. Experimental results show that, queuing Petri network can effectively reflect the architectural features of various cloud computing system performance perspective, services.

Renal surface reconstruction and segmentation for image‑guided surgical navigation of laparoscopic partial nephrectomy

Xiaohui Zhang,Xuquan Ji,Junchen Wang,Yubo Fan,Chunjing Tao 대한의용생체공학회 2023 Biomedical Engineering Letters (BMEL) Vol.13 No.2

real-time for laparoscopic image-guided navigation. The stereo vision method for intraoperative tissue 3D reconstructionhas the most potential for clinical development benefiting from its high reconstruction accuracy and laparoscopy compatibility. However, existing stereo vision methods have difficulty in achieving high reconstruction accuracy in real time. Also,intraoperative tissue reconstruction results often contain complex background and instrument information that preventsclinical development for image-guided systems. Taking laparoscopic partial nephrectomy (LPN) as the research object, thispaper realizes a real-time dense reconstruction and extraction of the kidney tissue surface. The central symmetrical Censusbased semi-global block stereo matching algorithm is proposed to generate a dense disparity map. A GPU-based pixel-bypixelconnectivity segmentation mechanism is designed to segment the renal tissue area. An in-vitro porcine heart, in-vivoporcine kidney and offline clinical LPN data were performed to evaluate the accuracy and effectiveness of our approach. The algorithm achieved a reconstruction accuracy of ± 2 mm with a real-time update rate of 21 fps for an HD image size of960 × 540, and 91.0% target tissue segmentation accuracy even with surgical instrument occlusions. Experimental resultshave demonstrated that the proposed method could accurately reconstruct and extract renal surface in real-time in LPN. Themeasurement results can be used directly for image-guided systems. Our method provides a new way to measure geometricinformation of target tissue intraoperatively in laparoscopy surgery.

SymWorkManager: A Novel HPC Multi-thread Programming Model

Xiaohui WEI,Hongliang LI,Shaocheng XING,Ji LI,Zane Zhenhua HU,Shutao YUAN 보안공학연구지원센터(IJGDC) 2009 International Journal of Grid and Distributed Comp Vol.2 No.1

Mechanism of rock breaking by pick assisted with water jet of different modes

Xiaohui Liu,Songyong Liu,Huifu Ji 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.12

In the rock breaking progress, the resistant force results in tools failure and the low cutting efficiency, thus, it is necessary to reduce thefailure of tools and enhance the efficiency of cutting and drilling. In this paper, different configuration modes of water jet were presentedto solve this issue. Moreover, the symmetrical pre-split finite element models for rock breaking by pick without water jet and picks assistedwith different configuration modes of water jet were established to analyze the effect of different configuration modes on rockstress distribution and pick cutting forces. Finally, the experiments were conducted to validate the theory analysis. The results indicatethat the cutting force decreasing rate of JCP is maximum all the time under the same conditions compared with the decreasing rate of JSPand JFP; and the numerical results were consistent with the numerical, which verifies the correctness of theory analysis.

HSKAS : A Novel Hierarchical Shared Key Authentication Scheme in Wireless Sensor Networks

Zeyu Sun,Xiaohui Ji,Yuanbo Li 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.4

Wireless sensor networks (WSNs) are often deployed in hostile environments, thus being subjected to great security risks. However, due to the influence of environment and dynamic topology, the communication radiuses of all nodes are no strictly consistent, which may cause different neighbor number and redundant neighbors for one central node. In this paper, we present a key agreement scheme without the trusted third parties by exploiting the special characteristics of Hopfield neural network: the two nodes converge in a steady state from their respective initial states after iterating finite times, while maintaining the confidentiality of the key by quantifying the key to strings. Compared to existing solution, the proposed method requires less memory and has lower communication overhead to key agreement.

Two-dimensional porous polyphthalocyanine (PPc) as an efficient gas-separation membrane for ammonia synthesis

Zhaoran Wang,Huilong Dong,Xiaohui Yu,Yujin Ji,Tingjun Hou,Youyong Li 한국물리학회 2017 Current Applied Physics Vol.17 No.12

Porous monolayer materials have been proven potential for gas separation and purification, because of their natural pathways of controllable sizes and well-ordered distribution. In this work, a novel material, two-dimensional (2D) porous polyphthalocyanine (PPc) is investigated by density functional theory (DFT) simulations for separating NH3 from H2 and N2 during ammonia synthesis process. Based on the calculated diffusion barriers through transition state search, we demonstrate that 2D PPc is able to offer high selectivity (107) of (H2, N2)/NH3 at room temperature. Further molecular dynamics (MD) simulation also indicates that the 2D PPc can effectively separate NH3 from H2 and N2. Thus the 2D PPc is promising for the practical applications of synthetic ammonia process.

Hippo signaling is intrinsically regulated during cell cycle progression by APC/C^Cdh1

Kim, Wantae,Cho, Yong Suk,Wang, Xiaohui,Park, Ogyi,Ma, Xueyan,Kim, Hanjun,Gan, Wenjian,Jho, Eek-hoon,Cha, Boksik,Jeung, Yun-ji,Zhang, Lei,Gao, Bin,Wei, Wenyi,Jiang, Jin,Chung, Kyung-Sook,Yang, Yingzi National Academy of Sciences 2019 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.116 No.19

<P><B>Significance</B></P><P>The Hippo signaling pathway is evolutionarily conserved in the animal kingdom and plays essential roles in regulating tissue growth during development and regeneration. We have identified APC/C<SUP>Cdh1</SUP>, a core component of cell cycle control machinery, as an evolutionarily conserved and previously unknown regulator of large tumor suppressor (LATS) kinases, which critically inhibit the YAP/TAZ transcription factors in transducing Hippo signaling. Our results suggest a model that APC/C<SUP>Cdh1</SUP> destabilizes LATS1/2 kinases in G1 phase of the cell cycle, leading to increased YAP/TAZ activities that promote G1/S transition by upregulating downstream gene expression, including <I>E2F1</I>. Our findings have important implications for a link between cell proliferation and LATS-regulated YAP/TAZ activities.</P><P>The Hippo-YAP/TAZ signaling pathway plays a pivotal role in growth control during development and regeneration and its dysregulation is widely implicated in various cancers. To further understand the cellular and molecular mechanisms underlying Hippo signaling regulation, we have found that activities of core Hippo signaling components, large tumor suppressor (LATS) kinases and YAP/TAZ transcription factors, oscillate during mitotic cell cycle. We further identified that the anaphase-promoting complex/cyclosome (APC/C)<SUP>Cdh1</SUP> E3 ubiquitin ligase complex, which plays a key role governing eukaryotic cell cycle progression, intrinsically regulates Hippo signaling activities. CDH1 recognizes LATS kinases to promote their degradation and, hence, YAP/TAZ regulation by LATS phosphorylation is under cell cycle control. As a result, YAP/TAZ activities peak in G1 phase. Furthermore, we show in <I>Drosophila</I> eye and wing development that Cdh1 is required in vivo to regulate the LATS homolog Warts with a conserved mechanism. Cdh1 reduction increased Warts levels, which resulted in reduction of the eye and wing sizes in a Yorkie dependent manner. Therefore, LATS degradation by APC/C<SUP>Cdh1</SUP> represents a previously unappreciated and evolutionarily conserved layer of Hippo signaling regulation.</P>