An evaluation of gestatistical texture for remote sensing data classification

Peijun, Li,Zhengxiao, Li 대한원격탐사학회 2001 International Symposium on Remote Sensing Vol.17 No.1

In this paper, texture measure derived from variogram in geostatistics is incorporated into image classification process to examine the effect of window size and lag distance changes on the overall accuracy. The measure is calculated at a specific lag of distance in a neighborhood using a moving window, to quantify the spatial variability of radiometric data at a local level. Computer programs have been written to create image texture as output file that is then used in the classification process as additional information. The application of the methodology to lithological discrimination using Landsat TM data is presented. The effects of variations in both lag spacing and window size on classification accuracy are analyzed and evaluated.

Joint SOC–SOP estimation method for lithium‑ion batteries based on electro‑thermal model and multi‑parameter constraints

Peijun Qin,Yanbo Che,Hongfeng Li,Yibin Cai,Mingda Jiang 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.3

Accurate estimations of the state of charge (SOC) and the state of power (SOP) are required to ensure efficient and reliable utilization of Li-ion batteries. A new joint estimation method of SOC–SOP based on the electro-thermal model and multi-parameter constraints is proposed in this paper. The proposed method introduces temperature as one of the important constraints for SOP and considers the intrinsic relationship between SOC and SOP as well as the influence of voltage, temperature, and SOC on SOP estimation. First, an electro-thermal model is developed to describe the electric and thermal dynamic characteristics of a battery. Second, the battery SOC is accurately estimated by the unscented Kalman filter method. Then the state of power of the battery is predicted under the condition of multi-parameter constraints. Finally, experiments are conducted to verify the effectiveness of the proposed method. Simulation and experimental results show that this method has a high degree of estimation accuracy and is very simple to calculate. Under the DST condition, the maximum relative voltage error within the electro-thermal model is about 5%. The maximum estimation error of the peak discharge power does not exceed 5 W, and the overall average estimation error is about 1.2 W.

An unsupervised marker image generation method for watershed segmentation of multispectral imagery

Peijun Li,Xiaobai Xiao 한국지질과학협의회 2004 Geosciences Journal Vol.8 No.3

Watershed transformation in mathematical morphology is a powerful tool for image segmentation. Watershed transformation based segmentation is generally a marker-controlled segmentation. This paper proposes a novel method of maker image generation based on unsupervised ISODATA classification. The method incorporates spectral information contained in multispectral data into watershed transformation for image segmentation. The method is evaluated and compared to existing unsupervised method. The results show that the proposed method could effectively reduce the oversegmentation effect and achieve more accurate segmentation results, compared to existing method. The combination of segmentation result and pixel-based classification is found to improve the overall classification accuracy over pixel-based classification.

Resonant Suppression of Flexible System Using Band-stop Filter

PeiJun Wu,ShaoKang Ma,Qiao Chen,Geng Yang,XuChun Li 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

A method is proposed for the resonant suppression of a flexible system based on vibration signal feedback. In addition to a torque, speed and position feedback control structure, this method filters some specific vibration frequencies of the output and then feedback them to the input of the system. Thus it is featured by a concise control structure and simple parameter design procedures. The paper firstly cites a three-mass system as an instance, in which the transfer function and the procedures of controller design are explained and the essential of resonant suppression is presented. Then we extend the controller design to a general flexible system which can be modelled as a more-masses system even with unequal qualities/inertias. Finally, a load force compensator is added to mitigate the disturbance caused by a load force. Simulation results show the validation of the method.

Integrated Disaster Risk Management of China

Peijun Shi,Jing Liu 환경독성보건학회 2007 한국독성학회 심포지움 및 학술발표회 Vol.- No.-

This paper concludes the present situation of disaster risk in China, including the general introduction of disaster risk (public security), the main accomplished government work in the integrated disaster riskmanagement field, and the achieved success and existing problems in this field. Based on this, according to the trend of global environment change and globalization development, the countermeasures of strengthening the integrated disaster risk management of China is put forward, namely adjusting the national integrated disaster risk management strategy, integrating security construction, emergency management, disaster mitigation and reduction and risk governance into an entity, taking the best advantage of the social guaranteeing and insurance's function in integrated risk management, building and improving the technology system and demonstration base of risk governance, strengthening the disaster reduction awareness and disaster reduction education ability, and facilitating the management and service ability of disaster risk information.

Stabilization of Linear Delay Systems With Two Unstable Poles by Modified PI Controller

Peijun Ju,Tongxing Li,Jing Lei,Zhongjin Guo 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.9

This paper investigates the stabilization problem of linear delay systems with two unstable poles, by using a modified proportional-integral (PI) controller. A necessary and sufficient condition for stabilizability is obtained, and the relationship between the system parameters and the time delay size is established. Furthermore, a tighter upper bound of the delay margin for the linear system with two unstable poles is provided. Finally, the effectiveness of the results is demonstrated by a simulation study.

Effect of Al2O3 Addition on Microwave Dielectric Properties of BaCo0.194Zn0.116Nb0.69O3 Ceramics

Peijun Liao,Tai Qiu,Jian Yang,Xinyi Lu 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.1

This study investigates the effects of Al2O3 addition on sintering, microstructures, phase formation and the microwave dielectric properties of BaCo0.194Zn0.116Nb0.69O3 (BCZN) ceramics prepared by the conventional solidstate route. Addition of low alumina content was found to effectively improve the Q×f value of BCZN ceramics. Addition of an appropriate amount of Al2O3 was found beneficial to the growth and uniformity of the ceramic grain, significantly improving the quality factor of BCZN ceramics. However, the performance of the ceramics deteriorated when an excessive secondary phase, inhomogeneous grain of small size and larger porosity were generated from the BCZN ceramic doped with excessive alumina. An optimum Q × f of 61056 GHz (f = 7.44 GHz) was obtained for the BCZN ceramic doped with 1 wt. % Al2O3 addition sintered at 1350°C for 3 h, which is markedly better than that of pure BCZN ceramic sintered at 1300°C for 3 h (13650 GHz, f = 7.02 GHz).

<i>Spatholobus suberectus</i> Exhibits Antidiabetic Activity In Vitro and In Vivo through Activation of AKT-AMPK Pathway

Zhao, Peijun,Alam, Md Badrul,Lee, Seok-hyun,Kim, Young-Jun,Lee, Seul,An, Hongyan,Choi, Hee-Jeong,Son, Hyeong-U,Park, Chul-Hong,Kim, Hyo-Hyun,Lee, Sang-Han Hindawi 2017 Evidence-based Complementary and Alternative Medic Vol.2017 No.-

<P>Glucose deposition in peripheral tissue is an important parameter for the treatment of type 2 diabetes mellitus. The aim of this study was to investigate the effects of<I> Spatholobus suberectus</I> (Ss) on glucose disposal in skeletal muscle cells and additionally explore its in vivo antidiabetic potential. Treatment of ethanolic extract of<I> S. suberectus</I> (EeSs) significantly enhanced the glucose uptake, mediated through the enhanced expression of GLUT4 in skeletal muscle via the stimulation of AKT and AMPK pathways in C2C12 cells. Moreover, EeSs have potential inhibitory action on <I>α</I>-glucosidase activity and significantly lowered the postprandial blood glucose levels in STZ-induced diabetic mice, associated with increased expression of GLUT4 and AKT and/or AMPK-mediated signaling cascade in skeletal muscle. Furthermore, administration of EeSs significantly boosted up the antioxidant enzyme expression and also mitigated the gluconeogenesis enzyme such as PEPCK and G-6-Pase enzyme expression in liver tissue of STZ-induced diabetic mice model. Collectively, these findings suggest that EeSs have a high potentiality to mitigate diabetic symptoms through stimulating glucose uptake in peripheral tissue via the activation of AKT and AMPK signaling cascade and augmenting antioxidant potentiality as well as blocking the gluconeogenesis process in diabetic mice.</P>

Antimelanogenic Effect of an <i>Oroxylum indicum</i> Seed Extract by Suppression of MITF Expression through Activation of MAPK Signaling Protein

Zhao, Peijun,Alam, Md Badrul,An, Hongyan,Choi, Hee-Jeong,Cha, Yeong Ho,Yoo, Chi-Yeol,Kim, Hyo-Hyun,Lee, Sang-Han MDPI 2018 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.19 No.3

<P>In this study, the antimelanogenic effect of an ethyl acetate fraction of <I>Oroxylum indicum</I> Vent. seeds (OISEA) and its underlying mechanisms in melan-a cells were investigated. Antimelanogenesis activity was confirmed by assessing inhibition of tyrosinase activity and melanin content in the cells. Both transcriptional and translational expression of microphthalmia-associated transcription factor (MITF), tyrosinase, and tyrosinase related protein-1 and 2 (TYRP-1 and TYRP-2), were also examined. The results depicted that pretreatment of OISEA significantly inhibits not only tyrosinase activity, but melanin production and intracellular tyrosinase activity. By repressing the expression of tyrosinase, TYRP-1, TYRP-2, and MITF, OISEA interrupted melanin production. Additionally, OISEA interfered with the phosphorylation of p38, extracellular signal-regulated kinase 1/2 (ERK1/2), and c-Jun N-terminal kinase (JNK), with the reversal of OISEA-induced melanogenesis inhibition after treatment with the specific inhibitors SB239063, U0126, and SP600125. Overall, these results suggest that OISEA can stimulate p38, ERK1/2, JNK phosphorylation, and subsequent suppression of melanin, leading to the inhibition of melanogenic enzymes and melanin production, possibly owing to the presence of polyphenolic compounds.</P>

Strength of connection fixed by TOBs considering out-of-plane tube wall deformation-Part 1: Tests and numerical studies

Tuoya Wulan,Peijun Wang,Chengxin Xia,Xinyu Liu,Mei Liu,Fangzhou Liu,Ou Zhao,Lulu Zhang 국제구조공학회 2022 Steel and Composite Structures, An International J Vol.42 No.1

This paper presents a study on the behavior of a bolted T-stub to square tube connection using Thread-fixed Oneside Bolts (TOBs) through tests and numerical simulations. It outlines a research work of four connections with focus on the failure modes and strengths of the connection under tensile load. It was observed that the thread anchor failure caused by shear failure of hole threads controlled the final failure of the connection in the tests. Meanwhile, the out-of-plane deformation of tube wall resulted in the contact separation between hole threads and bolt threads, which in turn reduced the shear strength of hole threads. Finite element models (FEMs) allowing for the configuration details of the TOBs fixed connection are then developed and compared with the test results. Subsequently, the failure mechanism of hole threads and stress distribution of each component are analyzed based on FEM results. It was concluded that the ultimate strength of connection was not only concerned with the shear strength of hole threads, but also was influenced by the plastic out-of-plane deformation of tube wall. These studies lay a foundation for the establishment of suitable design methods of this type of connection.