Time-domain analyses of the layered soil by the modified scaled boundary finite element method

Shan Lu,Jun Liu,Gao Lin,Wenyuan Wang 국제구조공학회 2015 Structural Engineering and Mechanics, An Int'l Jou Vol.55 No.5

The dynamic response of two-dimensional unbounded domain on the rigid bedrock in the time domain is numerically obtained. It is realized by the modified scaled boundary finite element method (SBFEM) in which the original scaling center is replaced by a scaling line. The formulation bases on expanding dynamic stiffness by using the continued fraction approach. The solution converges rapidly over the whole time range along with the order of the continued fraction increases. In addition, the method is suitable for large scale systems. The numerical method is employed which is a combination of the time domain SBFEM for far field and the finite element method used for near field. By using the continued fraction solution and introducing auxiliary variables, the equation of motion of unbounded domain is built. Applying the spectral shifting technique, the virtual modes of motion equation are eliminated. Standard procedure in structural dynamic is directly applicable for time domain problem. Since the coefficient matrixes of equation are banded and symmetric, the equation can be solved efficiently by using the direct time domain integration method. Numerical examples demonstrate the increased robustness, accuracy and superiority of the proposed method. The suitability of proposed method for time domain simulations of complex systems is also demonstrated.

Ginsenoside compound K protects human umbilical vein endothelial cells against oxidized low-density lipoprotein-induced injury via inhibition of nuclear factor-kB, p38, and JNK MAPK pathways

Shan Lu,Yun Luo,Ping Zhou,Ke Yang,Guibo Sun,Xiaobo Sun 고려인삼학회 2019 Journal of Ginseng Research Vol.43 No.1

Background: Oxidized low-density lipoprotein (ox-LDL) causes vascular endothelial cell inflammatory response and apoptosis and plays an important role in the development and progression of atherosclerosis. Ginsenoside compound K (CK), a metabolite produced by the hydrolysis of ginsenoside Rb1, possesses strong anti-inflammatory effects. However, whether or not CK protects ox-LDL-damaged endothelial cells and the potential mechanisms have not been elucidated. Methods: In our study, cell viability was tested using a 3-(4, 5-dimethylthiazol-2yl-)-2,5-diphenyl tetrazolium bromide (MTT) assay. Expression levels of interleukin-6, monocyte chemoattractant protein-1, tumor necrosis factor-a, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 were determined by enzyme-linked immunosorbent assay and Western blotting. Mitochondrial membrane potential (DJm) was detected using JC-1. The cell apoptotic percentage was measured by the Annexin V/ propidium iodide (PI) assay, lactate dehydrogenase, and caspase-3 expression. Apoptosis-related proteins, nuclear factor (NF)-kB, and mitogen-activated protein kinases (MAPK) signaling pathways protein expression were quantified by Western blotting. Results: Our results demonstrated that CK could ameliorate ox-LDL-induced human umbilical vein endothelial cells (HUVECs) inflammation and apoptosis, NF-kB nuclear translocation, and the phosphorylation of p38 and c-Jun N-terminal kinase (JNK). Moreover, anisomycin, an activator of p38 and JNK, significantly abolished the anti-apoptotic effects of CK. Conclusion: These results demonstrate that CK prevents ox-LDL-induced HUVECs inflammation and apoptosis through inhibiting the NF-kB, p38, and JNK MAPK signaling pathways. Thus, CK is a candidate drug for atherosclerosis treatment.

Ginsenoside compound K protects human umbilical vein endothelial cells against oxidized low-density lipoprotein-induced injury via inhibition of nuclear factor-κB, p38, and JNK MAPK pathways

Lu, Shan,Luo, Yun,Zhou, Ping,Yang, Ke,Sun, Guibo,Sun, Xiaobo The Korean Society of Ginseng 2019 Journal of Ginseng Research Vol.43 No.1

Background: Oxidized low-density lipoprotein (ox-LDL) causes vascular endothelial cell inflammatory response and apoptosis and plays an important role in the development and progression of atherosclerosis. Ginsenoside compound K (CK), a metabolite produced by the hydrolysis of ginsenoside Rb1, possesses strong anti-inflammatory effects. However, whether or not CK protects ox-LDL-damaged endothelial cells and the potential mechanisms have not been elucidated. Methods: In our study, cell viability was tested using a 3-(4, 5-dimethylthiazol-2yl-)-2,5-diphenyl tetrazolium bromide (MTT) assay. Expression levels of interleukin-6, monocyte chemoattractant protein-1, tumor necrosis factor-${\alpha}$, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 were determined by enzyme-linked immunosorbent assay and Western blotting. Mitochondrial membrane potential (${\Delta}{\Psi}m$) was detected using JC-1. The cell apoptotic percentage was measured by the Annexin V/ propidium iodide (PI) assay, lactate dehydrogenase, and caspase-3 expression. Apoptosis-related proteins, nuclear factor $(NF)-{\kappa}B$, and mitogen-activated protein kinases (MAPK) signaling pathways protein expression were quantified by Western blotting. Results: Our results demonstrated that CK could ameliorate ox-LDL-induced human umbilical vein endothelial cells (HUVECs) inflammation and apoptosis, $NF-{\kappa}B$ nuclear translocation, and the phosphorylation of p38 and c-Jun N-terminal kinase (JNK). Moreover, anisomycin, an activator of p38 and JNK, significantly abolished the anti-apoptotic effects of CK. Conclusion: These results demonstrate that CK prevents ox-LDL-induced HUVECs inflammation and apoptosis through inhibiting the $NF-{\kappa}B$, p38, and JNK MAPK signaling pathways. Thus, CK is a candidate drug for atherosclerosis treatment.

Melatonin prevents lung injury by regulating apelin 13 to improve mitochondrial dysfunction

Lu Zhang,Fangli Liu,Xiaomin Su,Yue Li,Yining Wang,Ruonan Fang,Yingying Guo,Tongzhu Jin,Huitong Shan,Xiaoguang Zhao,Rui Yang,Hongli Shan,Haihai Liang 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

Pulmonary fibrosis is a progressive disease characterized by epithelial cell damage, fibroblast proliferation, excessive extracellular matrix (ECM) deposition, and lung tissue scarring. Melatonin, a hormone produced by the pineal gland, plays an important role in multiple physiological and pathological responses in organisms. However, the function of melatonin in the development of bleomycin-induced pulmonary injury is poorly understood. In the present study, we found that melatonin significantly decreased mortality and restored the function of the alveolar epithelium in bleomycin-treated mice. However, pulmonary function mainly depends on type II alveolar epithelial cells (AECIIs) and is linked to mitochondrial integrity. We also found that melatonin reduced the production of reactive oxygen species (ROS) and prevented apoptosis and senescence in AECIIs. Luzindole, a nonselective melatonin receptor antagonist, blocked the protective action of melatonin. Interestingly, we found that the expression of apelin 13 was significantly downregulated in vitro and in vivo and that this downregulation was reversed by melatonin. Furthermore, ML221, an apelin inhibitor, disrupted the beneficial effects of melatonin on alveolar epithelial cells. Taken together, these results suggest that melatonin alleviates lung injury through regulating apelin 13 to improve mitochondrial dysfunction in the process of bleomycin-induced pulmonary injury.

The Current and Future Prospects for International Port Distribution Centers in Kaohsiung Harbor

Lu, Chin-Shan 한국해운학회 2000 해운물류연구 Vol.31 No.-

This study has described the importance of international distribution in the development of port function, with particular reference to the Port of Kaohsiung. A comparative analysis of the logistics costs of MCC (Multiple Countries Consolidation Cargo) in distribution centers in Kaohsiung and Hong Kong Ports provides a general framework for the identification of logistics costs from a shipper's perspective. The results indicate that total logistics cost per TEU in distribution centers in Kaohsiung Port was cheaper than in Hong Kong Port. However, non-cost related factors such as customer service, location, turnaround time of cargo handling, availability of space, and frequency of ship call, etc. should be evaluated in the future analysis. In addition, it is essential to investigate the market for distribution centers from a demand side.

Efficient Kernel Based 3-D Source Localization via Tensor Completion

( Shan Lu ),( Jun Zhang ),( Xianmin Ma ),( Changju Kan ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.1

Source localization in three-dimensional (3-D) wireless sensor networks (WSNs) is becoming a major research focus. Due to the complicated air-ground environments in 3-D positioning, many of the traditional localization methods, such as received signal strength (RSS) may have relatively poor accuracy performance. Benefit from prior learning mechanisms, fingerprinting-based localization methods are less sensitive to complex conditions and can provide relatively accurate localization performance. However, fingerprinting-based methods require training data at each grid point for constructing the fingerprint database, the overhead of which is very high, particularly for 3-D localization. Also, some of measured data may be unavailable due to the interference of a complicated environment. In this paper, we propose an efficient kernel based 3-D localization algorithm via tensor completion. We first exploit the spatial correlation of the RSS data and demonstrate the low rank property of the RSS data matrix. Based on this, a new training scheme is proposed that uses tensor completion to recover the missing data of the fingerprint database. Finally, we propose a kernel based learning technique in the matching phase to improve the sensitivity and accuracy in the final source position estimation. Simulation results show that our new method can effectively eliminate the impairment caused by incomplete sensing data to improve the localization performance.

A multifunctional lactic acid based plasticizer used for plasticizing PVC and PLA: Endowing PLA elastic restore capability

Minjia Lu,Pingping Jiang,Pingbo Zhang,Shan Feng,Zhixuan Cui,Qingkui Song,Yong Zhao,Jingxian Shen,Yiyi Fan,Huixian Lu 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.128 No.-

A novel multifunctional plasticizer, cyclohexyl triethylene glycol oligo-lactate (CTLE) was designed by atwo-step esterification reaction using green non-toxic biomass lactic acid as raw material. Its structurewas characterized by 1H NMR, FT-IR and TOF-MS. Thermogravimetric analysis (TGA), tensile test andleaching test were used to evaluate the plasticizer effect of PVC or PLA blends. Compared with commercialplasticizers, CTLE showed more outstanding thermal stability, flexibility and migration stability. Under the same condition with the addition of 50 phr plasticizer, the CTLE plasticized PVC film hadthe lowest glass transition temperature (TgCTLE-50 = 24.6 C) and the highest initial decomposition temperature(TiCTLE-50 = 265.4 C). In PLA blends, only the CTLE plasticized PLA film could recover after fracture,and the stress relaxation test results showed that the stress value of PLA-CTLE-20 drops sharply to anon-zero value, showing elastic characteristics. We estimate that the excellent plasticity of CTLE is due toits molecular structure. Among them, a large number of polar groups form intermolecular forces withPVC chain segments to make the binding tight, and the ring structure increases the free volume betweenPVC chain segments.

Assessment of National Logistics Competence in Taiwan, Vietnam, and Malaysia

Chin-Shan LU,Chi-Chang LIN 한국해운물류학회 2012 The Asian journal of shipping and Logistics Vol.28 No.2

This research aims to examine national logistics competence in Taiwan, Vietnam and Malaysia from a manufacturer’s perspective. Using survey responses from 459 manufacturing firms, this study compares the relative importance and satisfaction of national logistics competency. Results indicated that simplify the customs clearance procedure was viewed as the most important item of national logistics competency in Taiwan, whereas inland transport linkage and eradication of corruption have been emphasized by the respondents in Vietnam and Malaysia. In general, Taiwan is higher than Vietnam and Malaysia in terms of the level of satisfaction. Importance-satisfaction analysis was also employed to assess critical national logistics competency that needs to be improved in Taiwan, Vietnam, and Malaysia. Theoretical and practical implications from the results ndings for government or agency were discussed in this research.

The Impact of Seafarers’ Perceptions of National Culture and Leadership on Safety Attitude and Safety Behavior in Dry Bulk Shipping

Chin-Shan LU,Chen-Ning HSU,Chen-Han LEE 국제이네비해양경제학회 2016 International Journal of e-Navigation and Maritime Vol.4 No.1

This research aims to examine the effects of national culture and leadership style on safety performance in bulk shipping companies. Survey data collected from 322 respondents working in dry bulk carriers was used, a multiple regression analysis was conducted to analyze the influence of national culture and leadership styles (i.e. transformational, passive management, and contingent reward) on safety attitude and safety behavior. The results indicate that national culture dimensions such as power distance, uncertainty avoidance, collectivism, and long-term orientation had a positive influence on safety behaviour. Long-term orientation had a positive influence on safety attitude, whereas masculinity had a negative influence on safety attitude of seafarers. Specifically, this research found that transformational leadership had a positive influence on safety attitude and safety behaviour of seafarers. Moreover, practical implication from the research findings to improve ship safety in dry bulk shipping were discussed.

A New Variational Bayesian-based Kalman Filter with Random Measurement Delay and Non-Gaussian Noises

Chenghao Shan,Weidong Zhou,Hanyu Shan,Lu Liu 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.8

To improve the estimation accuracy of the Kalman filter in the scenario of random measurement delay and non-Gaussian process and measurement noises, a new variational Bayesian (VB)-based Kalman filter is proposed in this paper. First, the state expansion method and Bernoulli random variable (BRV) are utilized to characterize random measurement delay. Second, the one-step predicted probability density function (PDF) and measurement noise vectors are modeled as Student’s t (ST) distributions. Third, the likelihood function of two ST distributions is converted from a weighted sum to an exponential product to establish a hierarchical Gaussian state space model (HGSSM). Finally, the system state, BRV and intermediate random variables (IRV) are simultaneously estimated using the variational Bayesian (VB) method. Simulation experiment results indicate that the proposed filter has superior estimation performance to current filters to address the filtering problem of random measurement delay and non-Gaussian process and measurement noises.