Structural, magnetic properties of nickel-substituted strontium W-type ferrites

Jinsong Li,Xiubin Zhao,Ailin Xia 한양대학교 청정에너지연구소 2023 Journal of Ceramic Processing Research Vol.24 No.5

Nickel substituted W-type strontium ferrites Sr0.9Ce0.1Zn2-xNixFe16O27 (x=0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) were prepared by aceramic method. The specimens exhibited a single-phase W-type structure when the Ni content (x) is 0 ≤ x ≤ 1. With theincreasing content of nickel dopant, the particles exhibited a hexagonal plate-like shape. The saturation magnetization andremanent magnetization increased x from 0.0 to 0.6, then decreased with x > 0.6. The coercivity of specimens increasedgradually for x ≤ 0.2 and then began to decrease from x = 0.3; the coercivity shows a downward trend with the Ni contentcontinuing to increase. Subsequently, as the Ni content increases, there is a downward trend compared to the unsubstitutedspecimens.

Bridge-vehicle coupled vibration response and static test data based damage identification of highway bridges

Jinsong Zhu,Qiang Yi 국제구조공학회 2013 Structural Engineering and Mechanics, An Int'l Jou Vol.46 No.1

In order to identify damage of highway bridges rapidly, a method for damage identification using dynamic response of bridge induced by moving vehicle and static test data is proposed. To locate damage of the structure, displacement energy damage index defined from the energy of the displacement response time history is adopted as the indicator. The displacement response time histories of bridge structure are obtained from simulation of vehicle-bridge coupled vibration analysis. The vehicle model is considered as a four-degree-of-freedom system, and the vibration equations of the vehicle model are deduced based on the D’Alembert principle. Finite element method is used to discretize bridge and finite element model is set up. According to the condition of displacement and force compatibility between vehicle and bridge, the vibration equations of the vehicle and bridge models are coupled. A Newmark-β algorithm based professional procedure VBAP is developed in MATLAB, and used to analyze the vehicle-bridge system coupled vibration. After damage is located by employing the displacement energy damage index, the damage extent is estimated through the least-square-method based model updating using static test data. At last, taking one simply supported bridge as an illustrative example, some damage scenarios are identified using the proposed damage identification methodology. The results indicate that the proposed method is efficient for damage localization and damage extent estimation.

A SYSTEM OF NONLINEAR VARIATIONAL INCLUSIONS WITH GENERAL H-MONOTONE OPERATORS IN BANACH SPACES

Jinsong Li,Wei Wang,조민형,강신민 영남수학회 2010 East Asian mathematical journal Vol.26 No.5

A system of nonlinear variational inclusions involving general H-monotone operators in Banach spaces is introduced. Using the resolvent operator technique, we suggest an iterative algorithm for finding approximate solutions to the system of nonlinear variational inclusions, and establish the existence of solutions and convergence of the iterative algorithm for the system of nonlinear variational inclusions.

On generalized nonlinear quasivariational inequalities

Jinsong Li,강신민 영남수학회 2009 East Asian mathematical journal Vol.25 No.2

In this paper, we introduce a new generalized nonlinear quasivariational inequality and establish its equivalence with a fixed point problem by using the resolvent operator technique. Utilizing this equivalence, we suggest two iterative schemes, prove two existence theorems of solutions for the generalized nonlinear quasivariational inequality involving generalized cocoercive mapping and establish some convergence results of the sequences generated by the algorithms. Our results include several previously known results as special cases.

Vehicle-bridge coupling vibration analysis based fatigue reliability prediction of prestressed concrete highway bridges

Jinsong Zhu,Cheng Chen,Qinghua Han 국제구조공학회 2014 Structural Engineering and Mechanics, An Int'l Jou Vol.49 No.2

The extensive use of prestressed reinforced concrete (PSC) highway bridges in marine environment drastically increases the sensitivity to both fatigue- and corrosion-induced damage of their critical structural components during their service lives. Within this scenario, an integrated method that is capable of evaluating the fatigue reliability, identifying a condition-based maintenance, and predicting the remaining service life of its critical components is therefore needed. To accomplish this goal, a procedure for fatigue reliability prediction of PSC highway bridges is proposed in the present study. Vehicle-bridge coupling vibration analysis is performed for obtaining the equivalent moment ranges of critical section of bridges under typical fatigue truck models. Three-dimensional nonlinear mathematical models of fatigue trucks are simplified as an eleven-degree-of-freedom system. Road surface roughness is simulated as zero-mean stationary Gaussian random processes using the trigonometric series method. The time-dependent stress-concentration factors of reinforcing bars and prestressing tendons are accounted for more accurate stress ranges determination. The limit state functions are constructed according to the Miner’s linear damage rule, the time-dependent S-N curves of prestressing tendons and the site-specific stress cycle prediction. The effectiveness of the methodology framework is demonstrated to a T-type simple supported multi-girder bridge for fatigue reliability evaluation.

Existence and iterative approximations of solutions for strongly nonlinear variational-like inequalities

Jinsong Li,Juhe Sun,강신민 영남수학회 2011 East Asian mathematical journal Vol.27 No.5

In this paper, we introduce and study a new class of strongly nonlinear variational-like inequalities. Under suitable conditions, we prove the existence of solutions for the class of strongly nonlinear variational-like inequalities. By making use of the auxiliary principle technique, we suggest an iterative algorithm for the strongly nonlinear variational-like inequality and give the convergence criteria of the sequences generated by the iterative algorithm.

Bias Atlases for Segmentation-Based PET Attenuation Correction Using PET-CT and MR

Jinsong Ouyang,Se Young Chun,Petibon, Yoann,Bonab, Ali A.,Alpert, Nathaniel,El Fakhri, Georges IEEE 2013 IEEE transactions on nuclear science Vol.60 No.5

<P>This study was to obtain voxel-wise PET accuracy and precision using tissue-segmentation for attenuation correction. We applied multiple thresholds to the CTs of 23 patients to classify tissues. For six of the 23 patients, MR images were also acquired. The MR fat/in-phase ratio images were used for fat segmentation. Segmented tissue classes were used to create attenuation maps, which were used for attenuation correction in PET reconstruction. PET bias images were then computed using the PET reconstructed with the original CT as the reference. We registered the CTs for all the patients and transformed the corresponding bias images accordingly. We then obtained the mean and standard deviation bias atlas using all the registered bias images. Our CT-based study shows that four-class segmentation (air, lungs, fat, other tissues), which is available on most PET-MR scanners, yields 15.1%, 4.1%, 6.6%, and 12.9% RMSE bias in lungs, fat, non-fat soft-tissues, and bones, respectively. An accurate fat identification is achievable using fat/in-phase MR images. Furthermore, we have found that three-class segmentation (air, lungs, other tissues) yields less than 5% standard deviation of bias within the heart, liver, and kidneys. This implies that three-class segmentation can be sufficient to achieve small variation of bias for imaging these three organs. Finally, we have found that inter- and intra-patient lung density variations contribute almost equally to the overall standard deviation of bias within the lungs.</P>

Comparison of Multiple Chronic Obstructive Pulmonary Disease (COPD) Indices in Chinese COPD Patients

( Jinsong Zhang ),( Anastasia Miller ),( Yongxia Li ),( Qinqin Lan ),( Ning Zhang ),( Yanling Chai ),( Bing Hai ) 대한결핵 및 호흡기학회 2018 Tuberculosis and Respiratory Diseases Vol.81 No.2

Background: Chronic obstructive pulmonary disease (COPD) is a serious chronic condition with a global impact. Symptoms of COPD include progressive dyspnea, breathlessness, cough, and sputum production, which have a considerable impact on the lives of patients. In addition to the human cost of living with COPD and the resulting death, COPD entails a huge economic burden on the Chinese population, with patients spending up to one-third of the average family income on COPD management in some regions is clinically beneficial to adopt preventable measures via prudent COPD care utilization, monetary costs, and hospitalizations. Methods: Toward this end, this study compared the relative effectiveness of six indices in predicting patient healthcare utilization, cost of care, and patient health outcome. The six assessment systems evaluated included the three multidimensional Body mass index, Obstruction, Dyspnea, Exercise capacity index, Dyspnea, Obstruction, Smoking, Exacerbation (DOSE) index, and COPD Assessment Test index, or the unidimensional measures that best predict the future of patient healthcare utilization, cost of care, and patient health outcome among Chinese COPD patients. Results: Multiple linear regression models were created for each healthcare utilization, cost, and outcome including a single COPD index and the same group of demographic variables for each of the outcomes. Conclusion: We conclude that the DOSE index facilitates the prediction of patient healthcare utilization, disease expenditure, and negative clinical outcomes. Our study indicates that the DOSE index has a potential role beyond clinical predictions.

Regeneration mechanism of CeO2-TiO2 sorbents for elemental mercury capture from syngas

Jinsong Zhou,Kunzan Qiu,Wenhui Hou,Shuaiqi Meng,Xiang Gao 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.3

The characteristics of mercury desorption on spent CeO2-TiO2 (CeTi) sorbents were investigated to improve the cyclic regeneration removal activity. Mercury was significantly released in the form of elemental mercury at temperatures ranging from 250 to 280 oC. Mercury desorption had a significant correlation with regeneration temperature, but was independent of the heating rate and regeneration conditions. The optimal regeneration temperature was 500 oC. The CeTi sorbents could be easily restored by simple heating and exhibited superior activity over several capture- regeneration cycles. The amount of released mercury almost equaled the adsorbed mercury on the surface of the CeTi sorbent, indicating that most of the adsorbed mercury was released during the heating process.

A Novel Natural Dye Derivative for Natural Fabric Supercritical Carbon Dioxide Dyeing Technology

Jinsong Wu,Hongjuan Zhao,Mingyue Wang,Weiru Zhi,Xiaoqing Xiong,Laijiu Zheng 한국섬유공학회 2019 Fibers and polymers Vol.20 No.11

The supercritical carbon dioxide (SC-CO2) dyeing technology is a green dyeing technology, and the usage ofnatural dye makes SC-CO2 dyeing technology safer and more environment-friendly. Nevertheless, after using natural dye inSC-CO2 dyeing, the color depth and fastness of dyed natural fabric are poor. In this study, alkyl and hydroxyalkyl groupswere grafted onto alizarin, which is a natural dye, to elevate the color depths and fastness of alizarin-derivative-dyed naturalfabric. The results demonstrate that the color depths of alkyl-alizarin-dyed and hydroxyalkyl-alizarin-dyed natural fabricswere increased. This has to do with the increase in the solubilities of alkyl alizarin and hydroxyalkyl alizarin in SC-CO2. Thehydroxybutyl-alizarin-dyed wool displayed the best color depth (K/S value: 6.44). And the hydroxyalkyl-alizarin-dyednatural fabric showed good washing fastness and rubbing fastness (about 4-5 level), because that hydroxyalkyl alizarin couldbe linked by a covalent bond to the natural fabric.