An Analytical–Numerical Hybrid Method for Evaluating Out-of-Plane Stability of Buckling Restrained Braces

Yun Zhou,Chen Gong,Gen-Quan Zhong,Shi-yu Tian,Ming-Xiang Xiong 한국강구조학회 2021 International Journal of Steel Structures Vol.21 No.2

Out-of-plane stability of buckling restrained braces (BRBs) has been a critical concern for structural design of them under seismic loads. Although some calculation methods are available in literature catering for the determination of stability resistance of the BRBs, they showed complexities on dealing with numbers of parameters. In this paper, the mechanism of out-of-plane buckling failure of the BRBs was fi rstly introduced; then, an analytically and numerically hybrid method was proposed to calculate the out-of-plane stability resistance of the BRBs with considerations given to solve some key parameters; fi nally, the proposed hybrid method was verifi ed by test results of 4 BRB sub-frames subjected to the lateral loads. The results indicated that the out-of-plane bending deformation of BRB and gusset plate would occur under seismic loads. With an increasing rotation between the end of BRB and the inner core, the out-of-plane buckling failure happened owing to the existence of a plastic hinge at the bottom section of the outstanding part outside the inner core of the BRB. The outof- plane bending stiff ness of BRB and gusset plate, initial imperfection and bending moment capacity of the outstanding part are the key parameters aff ecting the out-of-plane stability of the BRBs. The proposed hybrid method is reasonable and eff ective to calculate the out-of-plane buckling capacity of the BRBs subject to diff erent combinations of axial force and end bending moments.

Performance Analysis of Packet Transport Network Communication for Integrated Wide-Area Protection

Sheng-ming Ge,Z Q Bo,Lin Wang,Zhan-feng Fan,Xing Liu,Feng-quan Zhou 보안공학연구지원센터 2016 International Journal of Grid and Distributed Comp Vol.9 No.3

As a new protection, wide-area protection enables protective relaying, and automatic control based on electric power system network communications and comprehensive judgment of multi-point information, which plays an increasingly important role in the secure and stable operation of electric power system. Interaction of wide-area information relies on communication network featuring high reliability and low time delay. On the other hand, most service of power transformation station is gradually towards IP and data oriented, along with the development of smart grid. This paper aims to introduce the wide-area protection technology supported by Packet Transport Network (PTN) communication technology, with analyzing the QoS (Quality of Service) network assurance architecture of PTN network, which establishes three planes, including transport plane, management plane, and control plane, based on ASON (Automatically Switched Optical Network) technology. After demonstrating the QoS assurance system of PTN from traffic control and transmission route, this paper introduces PTN networking test. Based on detailed parameters in the test results, the transmission performance of PTN on time delay, protection, and time synchronization of various electric power communication services are analyzed, with showing that PTN can fully meet the requirements of electric power communication.

Tetravalent half-arc-transitive graphs of order ^p4

Feng, Yan-Quan,Kwak, Jin Ho,Xu, Ming-Yao,Zhou, Jin-Xin Elsevier 2008 European journal of combinatorics : Journal europ& Vol.29 No.3

<P><B>Abstract</B></P><P>A graph is half-arc-transitive if its automorphism group acts transitively on vertices and edges, but not on arcs. It is known that for a prime p there is no tetravalent half-arc-transitive graphs of order p or <SUP>p2</SUP>. Xu [M.Y. Xu, Half-transitive graphs of prime-cube order, J. Algebraic Combin. 1 (1992) 275–282] classified the tetravalent half-arc-transitive graphs of order <SUP>p3</SUP>. As a continuation, we classify in this paper the tetravalent half-arc-transitive graphs of order <SUP>p4</SUP>. It shows that there are exactly p−1 nonisomorphic connected tetravalent half-arc-transitive graphs of order <SUP>p4</SUP> for each odd prime p.</P>

Integrated Protection Unit Design for Power Networks

Zhan-feng Fan,Sheng-ming Ge,Z Q Bo,Lin Wang,Feng-quan Zhou,Xing Liu,Guo-bing Song 보안공학연구지원센터 2016 International Journal of Grid and Distributed Comp Vol.9 No.4

This paper presents an hardware design solution for integrated protection of distribution systems (Network Protection Unit) by combining transient polarity comparison technique, which is based on the detection and processing of fault generated transient current signals. The integrated protection relays installed at each substation of a distribution network are communicated with the Network Protection Unit through specially designed Packet Transport Network (PTN) for fast and reliable transmission of transient polarity current signals. The relay detects the faulted generated super-imposed current signals. The transient polarity identification algorithm is then applied to the super-imposed signals to identify the polarity of the signal detected. The Network Protection Unit can collect all the transient polarity current signals under its protection area. Then The direction of a fault is determined by comparison of the polarity of the signals derived from all the line sections connected to the substation. The actual faulted section is identified by the Network Protection Unit through comparing the directional information from various stations. Simulation results presented in the paper demonstrate the feasibility of the scheme.

Tube Voltage, DNA Double-Strand Breaks, and Image Quality in Coronary CT Angiography

Lin Zhu Xiao,Zhou Fan,Schoepf U. Joseph,Pillai Balakrishnan,Zhou Chang Sheng,Quan Wei,Bao Xue Qin,Lu Guang Ming,Zhang Long Jiang 대한영상의학회 2020 Korean Journal of Radiology Vol.21 No.8

Objective: To evaluate the effects of tube voltage on image quality in coronary CT angiography (CCTA), the estimated radiation dose, and DNA double-strand breaks (DSBs) in peripheral blood lymphocytes to optimize the use of CCTA in the era of low radiation doses. Materials and Methods: This study included 240 patients who were divided into 2 groups according to the DNA DSB analysis methods, i.e., immunofluorescence microscopy and flow cytometry. Each group was subdivided into 4 subgroups: those receiving CCTA only with different tube voltages of 120, 100, 80, or 70 kVp. Objective and subjective image quality was evaluated by analysis of variance. Radiation dosages were also recorded and compared. Results: There was no significant difference in demographic characteristics between the 2 groups and 4 subgroups in each group (all p > 0.05). As tube voltage decreased, both image quality and radiation dose decreased gradually and significantly. After CCTA, γ-H2AX foci and mean fluorescence intensity in the 120-, 100-, 80-, and 70-kVp groups increased by 0.14, 0.09, 0.07, and 0.06 foci per cell and 21.26, 9.13, 8.10, and 7.13 (all p < 0.05), respectively. The increase in the DNA DSB level in the 120-kVp group was higher than those in the other 3 groups (all p < 0.05), while there was no significant difference in the DSBs levels among these latter groups (all p > 0.05). Conclusion: The 100-kVp tube voltage may be optimal for CCTA when weighing DNA DSBs against the estimated radiation dose and image quality, with further reductions in tube voltage being unnecessary for CCTA.

CFD computation of ship motions and added resistance for a high speed trimaran in regular head waves

Wu, Cheng-Sheng,Zhou, De-Cai,Gao, Lei,Miao, Quan-Ming The Society of Naval Architects of Korea 2011 International Journal of Naval Architecture and Oc Vol.3 No.1

Some research work on CFD computation of ship motions and added resistance in waves for a high speed trimaran is carried out in this paper. The governing equations, Reynolds Averaged Navier-Stokes and continuity equations are discretized by finite volume method. Volume of fluid method is adopted to deal with the nonlinear free surface. The incident waves are generated from the inflow boundary by prescribing a velocity profile resembling flexible flap wavemaker motions, and the outgoing waves are dissipated inside an artificial damping zone located at the rear part of the wave tank. In this paper, the computed results of ship motion and added resistance for a high speed trimaran are presented. The results of seakeeping experiment for the high speed trimaran carried out in CSSRC towing tank are also presented in this paper. Rather good agreements are shown between the computational and experimental results. The work in this paper provides a numerical tool for the study of seakeeping performance of high speed trimarans.

Production of IL-1β and Inflammasome with Up-Regulated Expressions of NOD-Like Receptor Related Genes in Toxoplasma gondii-Infected THP-1 Macrophages

Jia-Qi Chu,Ge Shi,Yi-Ming Fan,In-Wook Choi,Guang-Ho Cha,Yu Zhou,Young-Ha Lee,Juan-Hua Quan 대한기생충학열대의학회 2016 The Korean Journal of Parasitology Vol.54 No.6

Development and Validation of Nomograms to Provide Individualized Predictions of Sur-vival Benefits from Surgery in Patients with Intermediate/Advanced Hepatocel-lular Carcinoma

( Wen-tao Yan ),( Jia-he Wang ),( Ming-da Wang ),( Zheng Wang ),( Bing Quan ),( Ya-hao Zhou ),( Wei-min Gu ),( Hong Wang ),( Ting-hao Chen ),( Tian Yang ) 대한간학회 2018 춘·추계 학술대회 (KASL) Vol.2018 No.1

Aims: According to the BCLC treatment guidelines, surgery does not be recommended for intermediate/advanced hepatocellular carcinoma (HCC). In real world, however, liver resections are often performed in patients with intermediate/ advanced but resectable HCC, especially in the East. Methods: We retrospectively evaluated multicentric data of 1,325 patients newly diagnosed with intermediate/advanced HCC who underwent curative resection. We randomly divided the subjects into development (n = 875) and validation (n = 450) samples. Multivariate Cox proportional hazards models were developed and separately validated on the basis of patients’ clinicopathological variables assessed for associations with 1-year recurrence and 3-year mortality. The discriminatory accuracy of these models was compared with conventional tools by analyzing receiver operating characteristic (ROC) curves. Results: He statistical nomograms built based on performance status, Child-Pugh grade, portal hypertension, preoperative alpha-fetoprotein level, tumor rupture, largest tumor diameter, tumor number, macrovascular and microvascular invasion, and satellites had good calibration and discriminatory abilities, with c-indices of 0.70 (1-year recurrence) and 0.68 (3-year survival), respectively. These models showed satisfactory goodness-of-fit and discrimination abilities in the validation cohort (c-index, 0.68 for 1-year recurrence and 0.69 for 3-year survival). The areas under the ROC curve using these nomograms exceeded those of traditional staging systems, indicating superior discriminatory capability (c-indices, 0.60-0.63 and 0.56-0.62, respectively). Conclusions: Our proposed online nomograms, which present graphically postoperative prognostic models for recurrence and survival in patients with intermediate/advanced but resectable HCC, offer valuable guidance to surgeons and hepatologists for individually predicting survival benefits from surgery and planning recurrence surveillance and adjuvant therapy.

CFD computation of ship motions and added resistance for a high speed trimaran in regular head waves

Cheng-sheng Wu,De-cai Zhou,Lei Gao,Quan-ming Miao 대한조선학회 2011 International Journal of Naval Architecture and Oc Vol.3 No.1

Some research work on CFD computation of ship motions and added resistance in waves for a high speed trimaran is carried out in this paper. The governing equations, Reynolds Averaged Navier-Stokes and continuity equations are discretized by finite volume method. Volume of fluid method is adopted to deal with the nonlinear free surface. The incident waves are generated from the inflow boundary by prescribing a velocity profile resembling flexible flap wavemaker motions, and the outgoing waves are dissipated inside an artificial damping zone located at the rear part of the wave tank. In this paper, the computed results of ship motion and added resistance for a high speed trimaran are presented. The results of seakeeping experiment for the high speed trimaran carried out in CSSRC towing tank are also presented in this paper. Rather good agreements are shown between the computational and experimental results. The work in this paper provides a numerical tool for the study of seakeeping performance of high speed trimarans.

Prevalence and Risk Factors of Cerebral Small Vessel Disease in a Chinese Population-Based Sample

Fei Han,Fei-Fei Zhai,Quan Wang,Li-Xin Zhou,Jun Ni,Ming Yao,Ming-Li Li,Shu-Yang Zhang,Li-Ying Cui,Zheng-Yu Jin,Yi-Cheng Zhu 대한뇌졸중학회 2018 Journal of stroke Vol.20 No.2

Background and Purpose Epidemiological data of cerebral small vessel disease (CSVD) in the general population of China are lacking. We report on the prevalence of lacunes, white matter hyperintensity (WMH), and cerebral microbleeds (CMBs) in a community-based sample in China and compare the results with those of other studies. Methods This was a cross-sectional analysis of the population-based Shunyi Study in China. A total of 1,211 stroke-free participants (mean age, 55.6±9.3 years; 37.4% men) with available 3 Tesla (3T) magnetic resonance images were included in this analysis. Demographic information and risk factor data were assessed. The overall and age-specific prevalence of lacunes, WMH, and CMBs was evaluated. Associations between cardiovascular risk factors and the presence of these lesions were analyzed by multiple logistic regression. Results Our study showed a prevalence of 14.5% for lacunes, 72.1% for periventricular hyperintensity (PVH), 65.4% for deep white matter hyperintensity (DWMH), and 10.6% for CMBs. When compared with other community-based samples, individuals in the same age group showed a higher burden of lacunes and a relatively lower prevalence of CMBs. Advanced age was independently associated with the prevalence of these CSVD markers, while the presence of hypertension increased the risk of lacunes, PVH/DWMH, and CMBs in deep or infratentorial locations. Conclusions A higher burden of lacunes but a relatively lower prevalence of CMBs was observed in this Chinese population. This notable result highlights the challenge of CSVD prevention in China. Chinese have a risk factor profile for CSVD similar to those in other populations.