INTERVAL OSCILLATION THEOREMS FOR SECOND-ORDER DIFFERENTIAL EQUATIONS

Bin, Zheng The Korean Society for Computational and Applied M 2009 Journal of applied mathematics & informatics Vol.27 No.3

In this paper, we are concerned with a class of nonlinear second-order differential equations with a nonlinear damping term and forcing term: $$(r(t)k_1(x(t),x'(t)))'+p(t)k_2(x(t),x'(t))x'(t)+q(t)f(x(t))=0$$. Passage to more general class of equations allows us to remove a restrictive condition usually imposed on the nonlinearity. And, as a consequence, our results apply to wider classes of nonlinear differential equations. Some illustrative examples are considered.

Long Noncoding RNA MALAT1 Regulates Hepatocellular Carcinoma Growth Under Hypoxia via Sponging MicroRNA-200a

Zheng-Bin Zhao,Fei Chen,Xiao-Fang Bai 연세대학교의과대학 2019 Yonsei medical journal Vol.60 No.8

Purpose: Hepatocellular carcinoma (HCC) is a common cancer worldwide. Metastasis-associated lung adenocarcinoma transcript1 (MALAT1), a long noncoding RNA (lncRNA), has been reported to be aberrantly expressed in hypoxic cancer cells. MALAT1 playsa significant role in many malignancies, including HCC. The aim of this study was to explore the role of MALAT1 in hypoxic HCCcells and its underlying regulatory mechanism. Materials and Methods: Quantitative reverse transcription PCR (qRT-PCR) assay was performed to detect the mRNA levels ofMALAT1 and microRNA-200a (miR-200a) in HCC cells. Cell invasion and migration ability were evaluated by Transwell assay. Starbasev2.0 and luciferase reporter assay were employed to identify the association between MALAT1 and miR-200a. Cell proliferationand apoptosis were measured by MTT assay and flow cytometry, respectively. Results: MALAT1 levels were significantly upregulated in HCC cells under hypoxia. Hypoxia promoted proliferation, migration,and invasion, and blocked apoptosis in Hep3B cells, which were weakened by knockdown of MALAT1. Starbase v2.0 showed thatMALAT1 and miR-200a have a complementarity region, and luciferase reporter assay verified that MALAT1 interacted with miR-200a in Hep3B cells. Moreover, MALAT1 negatively regulated the expression of miR-200a. miR-200a levels were dramatically downregulatedin HCC cells under hypoxia. Upregulation of miR-200a inhibited proliferation, migration, and invasion, and inducedapoptosis in Hep3B cells under hypoxia. Interestingly, downregulation of miR-200a partially reversed the tumor-suppressive effectof knockdown of MALAT1 on Hep3B cells in hypoxic condition. Conclusion: LncRNA MALAT1 was involved in proliferation, migration, invasion, and apoptosis by interacting with miR-200a inhypoxic Hep3B cells, revealing a new mechanism of MALAT1 involved in hypoxic HCC progression.

High-Efficiency Non-contact Power Supply System

Zheng Bin,Kwan Dae-Hwan,Lee Dae-Sik 한국정보기술응용학회 2005 한국정보기술응용학회학술대회 Vol.2005 No.1

Achieving Distributed Consensus in Networked Flexible-joint Manipulator Systems via Energy-shaping Scheme

Bin Zheng,Jin Zhou,Jinchen Ji,Zhonghua Miao 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.7

This paper deals with the distributed consensus problem for networked flexible-joint manipulator systems which are formulated by underactuated Euler-Lagrange (EL) dynamics. Based on the energy-shaping scheme of passivity-based control (PBC) with interconnection and damping assignment, a novel decentralized controller is proposed to solve the leaderless and the leader-follower consensus problems. The main feature of the present work is the systematical integration of the energy of the systems composed of underactuated and actuated components and the energy of the controller as a total energy. Then the total energy is formulated as a suitable Lyapunov function to solve distributed consensus problems for the networked underactuated EL systems. The proposed consensus scheme without the need of velocity measurement possesses a relatively simple structure and good robustness. It is shown that interconnection pattern and damping assignment of the PBC are two key factors to affect the cooperative behavior of networked flexible-joint manipulator systems, which will be used to regulate or improve the cooperative performance of networked flexible-joint manipulator systems in practice. Finally, two numerical examples of networked six flexible-joint manipulator systems are presented to validate the correctness of the proposed algorithms.

Vesicular Stomatitis Virus G Glycoprotein and ATRA Enhanced Bystander Killing of Chemoresistant Leukemic Cells by Herpes Simplex Virus Thymidine Kinase/Ganciclovir

( Bin Yin ),( Chen Xi Hu ),( Zheng Chen ),( Wen Jun Zhao ),( Li Rong Wei ),( Yan Wen Zheng ),( Chao He ),( Yan Zeng ) 한국응용약물학회 2014 Biomolecules & Therapeutics(구 응용약물학회지) Vol.22 No.2

Vesicular Stomatitis Virus G Glycoprotein and ATRA EnhancedBystander Killing of Chemoresistant Leukemic Cells by HerpesSimplex Virus Thymidine Kinase/Ganciclovir

Interval oscillation theorems for second-order differential equations

Zheng Bin 한국전산응용수학회 2009 Journal of applied mathematics & informatics Vol.27 No.3

In this paper,we are concernedwith a class of nonlinear second- order differential equations with a nonlinear damping term and forcing term: (r(t)k1(x(t),x'(t)))' + p(t)k2(x(t),x'(t))x'(t) + q(t)f(x(t)) = 0. Passage to more general class of equations allows us to remove a restrictive condition usually imposed on the nonlinearity. And, as a consequence, our results apply to wider classes of nonlinear differential equations.Some illustrative examples are considered. In this paper,we are concernedwith a class of nonlinear second- order differential equations with a nonlinear damping term and forcing term: (r(t)k1(x(t),x'(t)))' + p(t)k2(x(t),x'(t))x'(t) + q(t)f(x(t)) = 0. Passage to more general class of equations allows us to remove a restrictive condition usually imposed on the nonlinearity. And, as a consequence, our results apply to wider classes of nonlinear differential equations.Some illustrative examples are considered.

A Fuzzy Sliding Mode Control for Rotational Inverted Pendulum

Zheng Bin,Dae-Sik Lee 한국지능시스템학회 2006 한국지능시스템학회 학술발표 논문집 Vol.16 No.2

Rotational inverted pendulum is a typical under-actuated system. For its highly nonlinear characteristic, a sliding mode controller is chosen for its robustness against the system uncertainties. Tow fuzzy inference mechanisms are applied in this paper to reduce the chattering phenomenon. One is proposed to construct a time-varying sliding surface. Another one is used to obtain the minimum upper bound of the uncertainties. A comparison between the conventional sliding mode and the fuzzy sliding mode is shown by simulations.

High Precision FE Modeling for Predicting Inner Polygon Defect of Hot Rolled Seamless Steel Tubes

Yong-Zheng Jiang,Yong-Zheng Jiang,Xiao-Ping Zhang,Kuan-Fang He,Guan-Fu Bin 대한토목학회 2018 KSCE Journal of Civil Engineering Vol.22 No.11

A high precision FE model is the key basis for cause analysis and overcoming of inner polygon defect of hot rolled seamless steel tubes. In this paper, the viscoelastic-plastic FEM is adopted in order to develop a high precision FE model for predicting the defect of inner polygon. Mechanical properties of tube material under rolling environment is obtained through five sets of high temperature compression tests, thus the viscoelastic-plastic constitutive equation of tube material is regressed and agrees with the tests results. Heat transfer boundary conditions, roll constant speed and contact friction boundary conditions are applied simultaneously on the FE model and thermo-mechanical coupled explicit algorithm is adopted for solution. The precision of the FE model is verified through industry experiments. Results shows the simulated inner wall shape is in good accordance with the experiment results, and the friction force, stress, strain and temperature distribution in the deformation zone are also discussed. It can be concluded that the viscoelastic-plastic FE model is of high precision and can be applied for better analysis of the hot rolling results.

Supper Efficiency DEA와 Malmquist 생산성 지수를 활용한 한 · 중 컨테이너터미널의 효율성 비교

정학빈(Zheng, Xue-Bin),김율성(Kim, Yul-Seong) 한국항만경제학회 2016 韓國港灣經濟學會誌 Vol.32 No.3

본 연구는 세계 20위권 컨테이너항만 중에서 한국과 중국 항만들의 개별 컨테이너터미널을 단위로 SE-DEA와 Malmquist 생산성지수법으로 2012년-2015년 사이의 효율성 및 생산성 변화추이를 분석하고자 하였다. 기존연구들에 비해 본 연구에서는 연구대상의 범위를 항만 내 터미널로 좁혀 더욱 세부적인 분석을 진행하여 실제 운영에 더욱 의미 있는 시사점을 제시하고자 하였다. SE-DEA 분석결과, 기존 연구와 달리 부산항 신항 주요 터미널은 중국 못지않은 효율성 및 생산성을 나타내고 있음을 밝혔다. 또한, Malmquist 생산성지수법 분석결과, 한국터미널의 평균 MPI지수는 1.051로 생산성이 연간 5.1% 향상되었고, 중국 터미널의 평균 MPI지수는 1.049로 생산성이 연간 4.9% 향상되었다. 2012년-2015년 한 · 중 양국 터미널의 평균 TCI지수는 각각 1.032와 1.0318로 MPI지수 변화에 중요한 요소로 작용하였다. 즉 생산성 제고는 운영효율성 개선보다 장비투입이나 기술개진을 통해 실현하였음을 설명한다. 미래에 경영의사결정을 함에 있어서 적극적인 시장개척을 통한 물량확보 증가와 운영효율성 제고를 통해 생산성을 개선하여야 한다. 향후 연구에서는 방법론의 다양화와 터미널 재무능력, 서비스 수준 등을 고려한 종합적인 효율성 분석이 필요할 것이다. The objective of this study was to select world top 20 major container terminals that belong to Korea and China as comparison units to analyze their efficiency and productivity trend. Super Efficiency Data Envelopment Analysis(SE-DEA) and Malmquist Productivity Index(MPI) models were applied to this study. Compared with previous studies, we narrowed down the scope of the comparison units to terminals and conducted more detailed analysis to present more meaningful implications to the actual operation. The different result from existing studies, SE-DEA analysis implied that the major terminals of Busan New Port showed similar efficiency and productivity with China’s terminals. In MPI analysis, the average index of Korean and China’s terminals is 1.051 and 1.049. The analysis indicates that the productivity was improved 5.1% and 4.9% annually. From 2012 to 2015, the average terminal TCI index of South Korea and China were 1.032 and 1.0318-the main factor which influences MPI. This means improving productivity mainly rely on investment in new equipment and technology upgrades rather than improve operational efficiency over the past few years. Future management decisions should consider more aggressive marketing to increase the volume and improve operational efficiency to enhance productivity. Further research should apply the overall efficiency of the methodology considering the financial diversification, terminal capacity, service levels, and other factors.

Effect of B-complex vitamins on the antifatigue activity and bioavailability of ginsenoside Re after oral administration

Yin Bin Chen,Yu Fang Wang,Wei Hou,Ying-Ping Wang,Sheng-Yuan Xiao,Yang Yang Fu,Jia Wang,Si Wen Zheng,Pei-He Zheng 고려인삼학회 2017 Journal of Ginseng Research Vol.41 No.2

Background: Both ginsenoside Re and B-complex vitamins are widely used as nutritional supplements. They are often taken together so as to fully utilize their antifatigue and refreshing effects, respectively. Whether actually a drugenutrient interaction exists between ginsenoside Re and B-complex vitamins is still unknown. The objective of this study was to simultaneously investigate the effect of B-complex vitamins on the antifatigue activity and bioavailability of ginsenoside Re after their oral administration. The study results will provide valuable theoretical guidance for the combined utilization of ginseng and B-complex vitamins. Methods: Ginsenoside Re with or without B-complex vitamins was orally administered to mice to evaluate its antifatigue effects and to rats to evaluate its bioavailability. The antifatigue activity was evaluated by the weight-loaded swimming test and biochemical parameters, including hepatic glycogen, plasma urea nitrogen, and blood lactic acid. The concentration of ginsenoside Re in plasma was determined by liquid chromatographyetandem mass spectrometry. Results: No antifatigue effect of ginsenoside Re was noted when ginsenoside Re in combination with Bcomplex vitamins was orally administered to mice. B-complex vitamins caused to a reduction in the bioavailability of ginsenoside Re with the area under the concentrationetime curve from zero to infinity markedly decreasing from 11,830.85 2,366.47 h$ng/mL to 890.55 372.94 h$ng/mL. Conclusion: The results suggested that there were pharmacokinetic and pharmacodynamic drugenutrient interactions between ginsenoside Re and B-complex vitamins. B-complex vitamins can significantly weaken the antifatigue effect and decrease the bioavailability of ginsenoside Re when simultaneously administered orally.