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      • Discrete Poisson Noise Logging Image Repair Based on Schatten Matrix Operator

        Zhang Jian,Yang Jie,Zhang bin 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.3

        In order to solve the problem that the present logging image reconstruction algorithm has certain staircase effect and ring effect during the discrete Poisson noise image repair process, a noise reduction algorithm based on Schatten matrix operator for discrete Poisson logging image is proposed in this article. Specifically, Schatten norm matrix of Hessian operator is adopted to estimate each pixel value of the image, and meanwhile the non-quadratic regularization function is adopted to eliminate the staircase effect; then Poisson measurement model is integrated with Schatten regularization function to construct the minimum objective function; then norm proximal mapping estimation algorithm is defined and is adopted to decouple the data fidelity item and the regularization matrix in the objective function, thus to recover the image. The simulation result shows: compared with present denoising technology, the algorithm proposed in this article has better repair effect and greater similarity in the aspect of processing the discrete Poisson noise.

      • SCIESCOPUS

        Seismic response simulations of bridges considering shear-flexural interaction of columns

        Zhang, Jian,Xu, Shi-Yu Techno-Press 2009 Structural Engineering and Mechanics, An Int'l Jou Vol.31 No.5

        Bridge columns are subjected to combined actions of axial force, shear force and bending moment during earthquakes, caused by spatially-complex earthquake motions, features of structural configurations and the interaction between input and response characteristics. Combined actions can have significant effects on the force and deformation capacity of RC columns, resulting in unexpected large deformations and extensive damage that in turn influences the performance of bridges as vital components of transportation systems. This paper evaluates the seismic response of three prototype reinforced concrete bridges using comprehensive numerical models that are capable of simulating the complex soil-structural interaction effects and nonlinear behavior of columns. An analytical approach that can capture the shear-flexural interacting behavior is developed to model the realistic nonlinear behavior of RC columns, including the pinching behavior, strength deterioration and stiffness softening due to combined actions of shear force, axial force and bending moment. Seismic response analyses were conducted on the prototype bridges under suites of ground motions. Response quantities of bridges (e.g., drift, acceleration, section force and section moment etc.) are compared and evaluated to identify the effects of vertical motion, structural characteristics and the shear-flexural interaction on seismic demand of bridges.

      • SCIESCOPUS

        Grouting effects evaluation of water-rich faults and its engineering application in Qingdao Jiaozhou Bay Subsea Tunnel, China

        Zhang, Jian,Li, Shucai,Li, Liping,Zhang, Qianqing,Xu, Zhenhao,Wu, Jing,He, Peng Techno-Press 2017 Geomechanics & engineering Vol.12 No.1

        In order to evaluate the grouting effects of water-rich fault in tunnels systematically, a feasible and scientific method is introduced based on the extension theory. First, eight main influencing factors are chosen as evaluation indexes by analyzing the changes of permeability, mechanical properties and deformation of surrounding rocks. The model of evaluating grouting effects based on the extension theory is established following this. According to four quality grades of grouting effects, normalization of evaluation indexes is carried out, aiming to meet the requirement of extension theory on data format. The index weight is allocated by adopting the entropy method. Finally, the model is applied to the grouting effects evaluation in water-rich fault F4-4 of Qingdao Jiaozhou Bay Subsea Tunnel, China. The evaluation results are in good agreement with the test results on the site, which shows that the evaluation model is feasible in this field, providing a powerful tool for systematically evaluating the grouting effects of water-rich fault in tunnels.

      • SCIESCOPUS

        Developments and applications of a modified wall function for boundary layer flow simulations

        Zhang, Jian,Yang, Qingshan,Li, Q.S. Techno-Press 2013 Wind and Structures, An International Journal (WAS Vol.17 No.4

        Wall functions have been widely used in computational fluid dynamics (CFD) simulations and can save significant computational costs compared to other near-wall flow treatment strategies. However, most of the existing wall functions were based on the asymptotic characteristics of near-wall flow quantities, which are inapplicable in complex and non-equilibrium flows. A modified wall function is thus derived in this study based on flow over a plate at zero-pressure gradient, instead of on the basis of asymptotic formulations. Turbulent kinetic energy generation ($G_P$), dissipation rate (${\varepsilon}$) and shear stress (${\tau}_{\omega}$) are composed together as the near-wall expressions. Performances of the modified wall function combined with the nonlinear realizable k-${\varepsilon}$ turbulence model are investigated in homogeneous equilibrium atmosphere boundary layer (ABL) and flow around a 6 m cube. The computational results and associated comparisons to available full-scale measurements show a clear improvement over the standard wall function, especially in reproducing the boundary layer flow. It is demonstrated through the two case studies that the modified wall function is indeed adaptive and can yield accurate prediction results, in spite of its simplicity.

      • A new geopolymeric grout blended completely weathered granite with blast-furnace slag

        Zhang, Jian,Li, Shucai,Li, Zhaofeng,Li, Hengtian,Du, Junqi,Gao, Yifan,Liu, Chao,Qi, Yanhai,Wang, Wenlong Techno-Press 2020 Advances in concrete construction Vol.9 No.6

        In order to reduce the usage of cement slurry in grouting engineering and consume the tunnel excavation waste soil, a new geopolymeric grouting material (GGM) was prepared by combine completely weathered granite (CWG) and blast-furnace slag (BFS), which can be applied to in-situ grouting treatment of completely weathered granite strata. The results showed CWG could participate in the geopolymerization process, and GGM slurry has the characteristics of short setting time, high flowability, low viscosity, high stone rate and high mechanical strength, and a design method of grouting pressure based on viscosity evolution was proposed. By adjusted the content of completely weathered granite and alkali activator concentration, the setting time of GGM were ranged from 5 to 30 minutes, the flowability was more than 23.5 cm, the stone rate was higher than 90%, the compressive strength of 28 days were 7.8-16.9 MPa, the porosity were below 30%. This provides a novel grouting treatment and utilizing excavated soil of tunnels in the similar strata.

      • SCISCIESCOPUS

        Direct <i>N</i>-Acylation of Lactams, Oxazolidinones, and Imidazolidinones with Aldehydes by Shvo’s Catalyst

        Zhang, Jian,Hong, Soon Hyeok American Chemical Society 2012 ORGANIC LETTERS Vol.14 No.17

        <P>Direct <I>N</I>-acylation of lactams, oxazolidinones, and imidazolidinones was achieved with aldehydes by Shvo’s catalyst without using any other stoichiometric reagent. The <I>N</I>-acylations with α,β-unsaturated aldehydes were achieved with excellent yields.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/orlef7/2012/orlef7.2012.14.issue-17/ol302087z/production/images/medium/ol-2012-02087z_0008.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ol302087z'>ACS Electronic Supporting Info</A></P>

      • Risk of New Vertebral Fracture and Combination Therapy with Zoledronic Acid and Teriparatide in Diabetic Patients after Percutaneous Kyphoplasty

        Zhang Jian,Yan Bin,Chen Zhe,Zheng Zhaomin,Yang Changsheng 대한척추외과학회 2021 Asian Spine Journal Vol.15 No.5

        Study Design: This was a retrospective clinical study. Purpose: This study aimed to evaluate the effect of combination therapy with zoledronic acid and teriparatide on the risk of new vertebral fracture (NVF) in type 2 diabetes mellitus (T2DM) patients after percutaneous kyphoplasty (PKP). Overview of Literature: Although T2DM had been associated with bone fragility and increased fracture risk, it remains unknown whether patients with T2DM could expect similar benefit from the combination therapy with zoledronic acid and teriparatide following PKP. Methods: Total 106 diabetic patients who had undergone PKP and had received anti-osteoporosis treatment for osteoporotic vertebral compression fracture were enrolled and allocated into the following two groups: group I (n=52, zoledronic acid) and group II (n=54, zoledronic acid plus teriparatide). The operating time, bone cement volume, and complications related to anti-osteoporosis treatment or PKP, if any, were recorded. The Visual Analog Scale (VAS) score and Oswestry Disability Index (ODI) were assessed at admission, at discharge, and at the final follow-up. Dual-energy X-ray absorptiometry scan of the hip for the measurement of the bone mineral density (BMD) was performed preoperatively and at the final follow-up for all the patients. Results: There was no significant difference in the age, body mass index, bone cement volume, or follow-up time of the groups. The mean follow-up duration was 22.5±1.6 months. All the patients had improved VAS and ODI, and group II had significantly better clinical outcomes than group I. All the patients had increased BMD at the latest follow-up, while group II exhibited significantly more improvement. The prevalence of NVF was lower in group II (11.5% vs. 7.4%, p=0.523). Male patients had a higher prevalence of NVF although the difference was not statistically significant. Conclusions: Combination therapy with zoledronic acid and teriparatide could improve the clinical outcomes, and BMD and had the potential to reduce NVF in diabetic patients following PKP.

      • Augmentation of poly(ADP-ribose) polymerase-dependent neuronal cell death by acidosis

        Zhang, Jian,Li, Xiaoling,Kwansa, Herman,Kim, Yun Tai,Yi, Liye,Hong, Gina,Andrabi, Shaida A,Dawson, Valina L,Dawson, Ted M,Koehler, Raymond C,Yang, Zeng-Jin SAGE Publications 2017 Journal of cerebral blood flow and metabolism Vol.37 No.6

        <P> Tissue acidosis is a key component of cerebral ischemic injury, but its influence on cell death signaling pathways is not well defined. One such pathway is parthanatos, in which oxidative damage to DNA results in activation of poly(ADP-ribose) polymerase and generation of poly(ADP-ribose) polymers that trigger release of mitochondrial apoptosis-inducing factor. In primary neuronal cultures, we first investigated whether acidosis per sé is capable of augmenting parthanatos signaling initiated pharmacologically with the DNA alkylating agent, N-methyl- N′-nitro- N-nitrosoguanidine. Exposure of neurons to medium at pH 6.2 for 4 h after N-methyl- N′-nitro- N-nitrosoguanidine washout increased intracellular calcium and augmented the N-methyl- N′-nitro- N-nitrosoguanidine-evoked increase in poly(ADP-ribose) polymers, nuclear apoptosis-inducing factor , and cell death. The augmented nuclear apoptosis-inducing factor and cell death were blocked by the acid-sensitive ion channel-1a inhibitor, psalmotoxin. In vivo, acute hyperglycemia during transient focal cerebral ischemia augmented tissue acidosis, poly(ADP-ribose) polymers formation, and nuclear apoptosis-inducing factor , which was attenuated by a poly(ADP-ribose) polymerase inhibitor. Infarct volume from hyperglycemic ischemia was decreased in poly(ADP-ribose) polymerase 1-null mice. Collectively, these results demonstrate that acidosis can directly amplify neuronal parthanatos in the absence of ischemia through acid-sensitive ion channel-1a . The results further support parthanatos as one of the mechanisms by which ischemia-associated tissue acidosis augments cell death. </P>

      • SCIESCOPUSKCI등재

        Polymorphism Identification, RH Mapping and Association of ${\alpha}$-Lactalbumin Gene with Milk Performance Traits in Chinese Holstein

        Zhang, Jian,Sun, Dongxiao,Womack, J.E.,Zhang, Yi,Wang, Yachun,Zhang, Yuan Asian Australasian Association of Animal Productio 2007 Animal Bioscience Vol.20 No.9

        Lactose synthase catalyses the formation of lactose which is the major osmole of bovine milk and regulates the milk volume. Alpha-lactalbumin (${\alpha}$-LA) is involved in the synthesis of lactose synthase in the mammary gland. Therefore ${\alpha}$-LA is regarded as a plausible candidate gene for the milk yield trait. To determine whether ${\alpha}$-LA is associated with milk performance traits, 1,028 Chinese Holstein cows were used to detect polymorphisms in the ${\alpha}$-LA by means of single-strand conformation polymorphism (SSCP). Two nucleotide transitions were identified in the 5'flanking region and intron 3 of ${\alpha}$-LA. Associations of such polymorphisms with five milk performance traits were analyzed using a general linear model procedure. No significant associations were observed between these polymorphisms and the five milk performance traits (p>0.05). RH mapping placed ${\alpha}$-LA on BTA5q21, linked most closely to markers U63110, CC537786 and L10347 (LOD>8.3), which is far distant from the region of the quantitative trait locus (QTL) on bovine chromosome 5 for variation in the milk yield trait. In summary, based on our findings, we eliminated these SNPs from having an effect on milk performance traits.

      • SCOPUSKCI등재

        Preparation and Properties of Modified Silicon-containing Arylacetylene Resin with Bispropargyl Ether

        Zhang, Jian,Huang, Jianxiang,Yu, Xiaojiao,Wang, Canfeng,Huang, Farong,Du, Lei Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.11

        A novel silicon-containing arylacetylene resin (MSAR) modified by dipropargyl ether of bisphenol A (DPBPA) and dipropargyl ether of perfluorobisphenol A (DPPFBPA) was prepared separately. The curing behaviors of modified resins, DPBPA/MSAR and DPPFBPA/MSAR, were characterized with differential scanning calorimeter (DSC). The kinetic parameters of modified resins were obtained by the Kissinger and Ozawa methods. The results of dynamic mechanical analysis (DMA) revealed that the glass transition temperature ($T_g$) of the cured DPBPA/MSAR reached $486^{\circ}C$. According to the thermogravimetric analysis (TGA), the decomposition temperature ($T_{d5}$) of the cured resins and char yield ($Y_c$, $800^{\circ}C$) decreased as the dipropargyl ether loadings increased, especially in air. With the same weight loading, thermal stability of DPBPA/MSAR was better than that of DPPFBPA/MSAR. The carbon fiber (T300) reinforced composites exhibited excellent flexural properties at room temperature with a high property retention at $300^{\circ}C$.

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