Failure characteristics of combined coal-rock with different interfacial angles

Zhao, Tong-Bin,Guo, Wei-Yao,Lu, Cai-Ping,Zhao, Guang-Ming Techno-Press 2016 Geomechanics & engineering Vol.11 No.3

In order to investigate the influence of the interfacial angel on failure characteristics and mechanism of combined coal-rock mass, 35 uniaxial/biaxial compressive simulation tests with 5 different interfacial angels of combined coal-rock samples were conducted by PFC2D software. The following conclusions are drawn: (1) The compressive strength and cohesion decrease with the increase of interfacial angle, which is defined as the angle between structure plane and the exterior normal of maximum principal plane, while the changes of elastic modulus and internal friction angle are not obvious; (2) The impact energy index $K_E$ decreases with the increase of interfacial angle, and the slip failure of the interface can be predicted based on whether the number of acoustic emission (AE) hits has multiple peaks or not; (3) There are four typical failure patterns for combined coal-rock samples including I (V-shaped shear failure of coal), II (single-fracture shear failure of coal), III (shear failure of rock and coal), and IV (slip rupture of interface); and (4) A positive correlation between interfacial angle and interface effect is shown obviously, and the interfacial angle can be divided into weak-influencing scope ($0-15^{\circ}$), moderate-influencing scope ($15-45^{\circ}$), and strong-influencing scope (> $45^{\circ}$), respectively. However, the confining pressure has a certain constraint effect on the interface effect.

Evaluation of Non-isothermal Melt Crystallization Kinetics of the Poly(lactic acid)/Graphene Composites under Variant Cooling Circumstances via Solidification Analysis Approach

Bin Yang,Peng Zhang,Shu-Chun Zhao,Ru Xia,Li-Fen Su,Ji-Bin Miao,Peng Chen,Jia-Sheng Qian,You Shi 한국고분자학회 2019 폴리머 Vol.43 No.5

The poly(lactic acid) (PLA)/graphene (GN) composites were prepared by solution blending. An in situ measurement technique was adopted to examine the non-isothermal crystallization of PLA/GN composites, which was different from the typical circumstances at constant cooling rate in DSC. The rheological properties of the samples were investigated, and the Carreau-A model was applied to non-linearly fit the rheological data. The non-isothermal crystallization kinetics and solidification behaviors at variant cooling rates were investigated using a modified version of Avrami equation by Jeziorny coupled with three-parameter model (TPM) and four-parameter model (FPM). Our findings showed that the viscosity of the PLA/GN composites dropped with increasing shear rate or GN content. Crystallization kinetic analysis suggested that GN served as an effective nucleating agent for PLA under non-isothermal melt crystallization conditions with variant cooling rate.

A Novel Hysteresis Control Strategy Based on Ampere-Second Balance of the Modulate Capacitor

Zhao, Jin-Bin,Dai, Jian-Feng,Qu, Ke-Qing,Li, Fen The Korean Institute of Power Electronics 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.6

A novel hysteresis PWM control strategy for synchronous buck converter is proposed. The proposed control strategy is based on ampere-second balance of the modulate capacitor, which not only offers faster transient response to meet the challenges of the power supply requirements of fast dynamic load changes, but also provides better stability and solves the compensation problem of error amplifier in the conversional voltage PWM control. Finally, the steady-state and dynamic operation of the control method is analyzed and verified by simulation and experimental results.

Designs and Simulations of Multi-factor in Trust Evaluation

Zhao Bin,He Jingsha,Huang Na,Zhang Yixuan,Zhou Shiyi,Ji Jie 보안공학연구지원센터 2015 International Journal of Database Theory and Appli Vol.8 No.1

Trust Model is an efficient way of resolving the trust problems in open networks in which trust evaluation is a key issue to be addressed in trust management. According to the design rules of trust models, the problem of the lack of dynamic adapt ability in trust evaluating, the lack of effective aggregation of trust and the lack of considerations to incentive mechanisms and so on, this paper introduced the bonus-penalty factor which shows how reliable is the direct trust of the recommend entities to the subject and evaluation reliability of the recommend entities which is used to decide whether the access object would adopt the recommendation of the recommend entities during the calculation of the recommend trust. The measurement of integrated trust solves the weight problem between direct trust and recommendatory trust by introducing balanced weight factor. Finally, we present designs of bonus-penalty function and balanced weight factor and simulations by Matlab software.

Temperature-dependent rheological behavior of cathode slurry for lithium-ion battery under steady and dynamic tests

Zhao Bin,Yin Deshun,Gao Yunfei,Ren Jiangtao 한국유변학회 2023 Korea-Australia rheology journal Vol.35 No.3

The rheological property of cathode slurry is commonly influenced by coating speed and mixing temperature, thereby leading to its storage stability and coating uniformity. In this study, the effect of the temperature of slurry on the rheological behaviors is investigated under various shear rates and temperatures based on steady and dynamic tests as well as theoretical models. In the flow experiments, the thixotropic behavior of the slurry is observed at all temperatures tested, and it is reduced with the increase in temperature. The experimental data is captured well by rheological models, and the model parameters are evaluated under the combined effects of shearing and temperature, resulting in two generalized state equations for the description of the flow properties of the slurry. In addition, microstructural rearrangement and polymeric entanglement at high temperatures cause viscosity and modulus to change, giving rise to complex rheological behavior in creep and oscillatory shear. Compared with slurry at 25 and 40 °C, both storage and loss moduli are dependent on oscillatory strain in the range of 0.1–1000% at 65 °C. The difference in characteristic strain corresponding to yielding and strain stiffening behavior is only observed at high temperatures, whereas relaxation times were independent of temperature in the oscillatory shear test. Understanding the effect of the temperature of slurry on rheological behaviors will be useful for improving the manufacturing efficiency of electrodes.

Study on Preemptive Real-Time Scheduling Strategy for Wireless Sensor Networks

ZHAO Zhi-bin,GAO Fuxiang 한국정보처리학회 2009 Journal of information processing systems Vol.5 No.3

Most of the tasks in wireless sensor networks (WSN) are requested to run in a real-time way. Neither EDF nor FIFO can ensure real-time scheduling in WSN. A real-time scheduling strategy (RTS) is proposed in this paper. All tasks are divided into two layers and endued diverse priorities. RTS utilizes a preemptive way to ensure hard real-time scheduling. The experimental results indicate that RTS has a good performance both in communication throughput and over-load. Most of the tasks in wireless sensor networks (WSN) are requested to run in a real-time way. Neither EDF nor FIFO can ensure real-time scheduling in WSN. A real-time scheduling strategy (RTS) is proposed in this paper. All tasks are divided into two layers and endued diverse priorities. RTS utilizes a preemptive way to ensure hard real-time scheduling. The experimental results indicate that RTS has a good performance both in communication throughput and over-load.

Energy simulation framework integrated with green manufacturing-enabled PLM information model

Zhao, Wen-Bin,Jeong, Jin-Woo,Noh, Sang Do,Yee, John T. SPRINGER 2015 INTERNATIONAL JOURNAL OF PRECISION ENGINEERING AND Vol. No.

Analysis on the creep response of bolted rock using bolted burgers model

Zhao, Tong-Bin,Zhang, Yu-Bao,Zhang, Qian-Qing,Tan, Yun-Liang Techno-Press 2018 Geomechanics & engineering Vol.14 No.2

In this paper, the creep behavior of bolted rock was analyzed by using the unconfined creep tests and the numerical results. Based on the test results, the Bolted Burgers creep model (B-B model) was proposed to clarify the creep mechanism of rock mass due to rock bolts. As to the simulation of the creep behaviour of bolted rock, a new user-defined incremental iterative format of the B-B model was established and the open-source $FLAC^{3D}$ code was written by using the object-oriented language (C++). To check the reliability of the present B-B creep constitutive model program, a numerical model of a tunnel with buried depth of 1000 m was established to analyze the creep response of the tunnel with the B-B model support, the non-support and the bolt element support. The simulation results show that the present B-B model is consistent with the calculated results of the inherent bolt element in $FLAC^{3D}$, and the convergence deformation can be more effectively controlled when the proposed B-B model is used in the $FLAC^{3D}$ software. The big advantage of the present B-B creep model secondarily developed in the $FLAC^{3D}$ software is the high computational efficiency.

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.

A Novel Hysteresis Control Strategy Based on Ampere-Second Balance of the Modulate Capacitor

Jin-Bin Zhao,Jian-Feng Dai,Ke-Qing Qu,Fen Li 전력전자학회 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.6

A novel hysteresis PWM control strategy for synchronous buck converter is proposed. The proposed control strategy is based on ampere-second balance of the modulate capacitor, which not only offers faster transient response to meet the challenges of the power supply requirements of fast dynamic load changes, but also provides better stability and solves the compensation problem of error amplifier in the conversional voltage PWM control. Finally, the steady-state and dynamic operation of the control method is analyzed and verified by simulation and experimental results.