IMPACTS OF WATER AND SEDIMENT LOAD CHANGE ON DEVELOPMENT OF MEANDERS IN LOWER YELLOW RIVER

CHANGZHI LI,ZHAOYIN WANG,JING ZHOU,JIXIANG LIU 한국수자원학회 2005 한국수자원학회 학술대회 Vol.2005 No.1

Decomposition-based multi-objective firefly algorithm for RFID network planning with uncertainty

Zhao, Chuanxin,Wu, Changzhi,Chai, Jian,Wang, Xiangyu,Yang, Xinmin,Lee, Jae-Myung,Kim, Mi Jeong Elsevier 2017 Applied soft computing Vol.55 No.-

<P>Radio frequency identification (RFID) is widely used for item identification and tracking. Due to the limited communication range between readers and tags, how to configure a RFID system in a large area is important but challenging. To configure a RFID system, most existing results are based on cost minimization through using 0/1 identification model. In practice, the system is interfered by environment and probabilistic model would be more reliable. To make sure the quality of the system, more objectives, such as interference and coverage, should be considered in addition to cost. In this paper, we propose a probabilistic-based multi-objective optimization model to address these challenges. The objectives to be optimized include number of readers, interference level and coverage of tags. A decomposition based firefly algorithm is designed to solve this multi-objective optimization problem. Virtual force is integrated into random walk to guide readers moving in order to enhance exploitation. Numerical simulations are introduced to demonstrate and validate our proposed method. Comparing with existing methods, such as Non-dominated Sorting Genetic Algorithm-II and Multi-objective Particle Swarm Optimization approaches, our proposed method can achieve better performance in terms of quality metric and generational distance under the same computational environment. However, the spacing metric of the proposed method is slightly inferior to those compared methods. (C) 2017 Elsevier B.V. All rights reserved.</P>

Maximizing lifetime of a wireless sensor network via joint optimizing sink placement and sensor-to-sink routing

Zhao, Chuanxin,Wu, Changzhi,Wang, Xiangyu,Ling, Bingo Wing-Kuen,Teo, Kok Lay,Lee, Jae-Myung,Jung, Kwang-Hyo Butterworths [etc.] 2017 Applied mathematical modelling Vol.49 No.-

<P><B>Abstract</B></P> <P>Wireless sensor networks typically contain hundreds of sensors. The sensors collect data and relay it to sinks through single hop or multiple hop paths. Sink deployment significantly influences the performance of a network. Since the energy capacity of each sensor is limited, optimizing sink deployment and sensor-to-sink routing is crucial. In this paper, this problem is modeled as a mixed integer optimization problem. Then, a novel layer-based diffusion particle swarm optimization method is proposed to solve this large-scaled optimization problem. In particular, two sensor-to-sink binding algorithms are combined as inner layer optimization to evaluate the fitness values of the solutions. Compared to existing methods that the sinks are selected from candidate positions, our method can achieve better performance since they can be placed freely within a geometrical plane. Several numerical examples are used to validate and demonstrate the performance of our method. The reported numerical results show that our method is superior to those existing. Furthermore, our method has good scalability which can be used to deploy a large-scaled sensor network.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Model jointly optimal sink placement and sensor-to-sink routing as a mixed integer optimization problem. </LI> <LI> Propose a discrete particle swarm optimization for sensor-to-sink routing. </LI> <LI> Develop a novel diffusion particle swarm optimization for sinks placement. </LI> <LI> Show superiority of our method over existing results through experimental comparisons. </LI> </UL> </P>

Incremental gradient-free method for nonsmooth distributed optimization

Li, Jueyou,Li, Guoquan,Wu, Zhiyou,Wu, Changzhi,Wang, Xiangyu,Lee, Jae-Myung,Jung, Kwang-Hyo AMERICAN INSTITUTE OF MATHEMATICAL SCIENCES 2017 JOURNAL OF INDUSTRIAL AND MANAGEMENT OPTIMIZATION Vol. No.

Ejector performance prediction at critical and subcritical operational modes

Li, Fenglei,Tian, Qi,Wu, Changzhi,Wang, Xiangyu,Lee, Jae-Myung Pergamon 2017 Applied thermal engineering Vol. No.

<P><B>Abstract</B></P> <P>Traditional ejector models are focusing on the ejector performance predictions at critical mode under design conditions. In reality, ejector systems cannot be operated under these conditions perfectly. Thus, the study of ejector performance at subcritical mode under off-design conditions is important. In this paper, novel models for ejector performance predictions at critical point and breakdown point are developed based on constant-pressure mixing and constant-pressure disturbing assumptions. Then, the two models are integrated as the model to predict ejector performance at critical and subcritical operational modes. In order to determine the ejector component efficiencies in the models, a novel concept, the effect of the change (EOC) of efficiency, is introduced to identify the efficiencies which affect ejector performance significantly. Then, the identified efficiencies are determined by sparsity-enhanced optimization method. The predicted results obtained by our model are much more accurate than those obtained by existing methods.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Novel models for ejector performance analysis at critical and breakdown points are developed. </LI> <LI> The models are integrated to predict ejector performance over entire operational range. </LI> <LI> An analysis method is developed for identifying the ejector component efficiencies. </LI> <LI> The performance prediction errors over entire operational range are within ±10%. </LI> </UL> </P>

Dynamic and static structural displacement measurement using backscattering DC coupled radar

Shanyue Guan,Jennifer A. Rice,Changzhi Li,Yiran Li,Guochao Wang 국제구조공학회 2015 Smart Structures and Systems, An International Jou Vol.16 No.3

Vibration-based monitoring is one approach used to perform structural condition assessment. By measuring structural response, such as displacement, dynamic characteristics of a structure may be estimated. Often, the primary dynamic responses in civil structures are below 5 Hz, making accurate low frequency measurement critical for successful dynamic characterization. In addition, static deflection measurements are useful for structural capacity and load rating assessments. This paper presents a DC coupled continuous wave radar to accurately detect both dynamic and static displacement. This low-cost radar sensor provides displacement measurements within a compact, wireless unit appropriate for a range of structural monitoring applications. The hardware components and operating mechanism of the radar are introduced and a series of laboratory experiments are presented to assess the performance characteristics of the radar. The laboratory and field experiments investigate the effect of factors such as target distance, motion amplitude, and motion frequency on the radar’s measurement accuracy. The results demonstrate that the radar is capable of both static and dynamic displacement measurements with sub-millimeter accuracy, making it a promising technology for structural health monitoring.

An Improved HB+ Protocol and its Application to EPC Global Class-1 Gen-2 Tags

Zhicai Shi,Jian Dai,Fei Wu,Yongxiang Xia,Yihan Wang,Changzhi Wang 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.8

RFID is a key technology that can be used to create the pervasive society. The EPCglobal Class-1 Gen-2 specification is an important standard for RFID. The tags conforming to this standard have limited computing and storing resources, and no more attentions are paid to their security and privacy. So the application of these tags is not secure. HB+ protocol is one of the typical lightweight authentication protocols suitable to these low-cost RFID tags. But it is vulnerable to active attacks. For some scenarios with frequent active attacks the efficiency of HB+ protocol will be degraded seriously. In order to improve the security and efficiency of HB+ protocol for some scenarios with frequent active attacks, a novel detection-exit-restart mechanism is proposed to monitor the integrity of the exchanged messages between the reader and the tag. The improved HB+ protocol can resist active attacks and it is more efficient and secure than HB+ protocol. This protocol only uses the computing resources embedded in tags and it is very suitable to low-cost RFID systems.

Numerical and experimental verifications on damping identification with model updating and vibration monitoring data

Jun Li,Hong Hao,Gao Fan,Pinghe Ni,Xiangyu Wang,Changzhi Wu,이제명,정광효 국제구조공학회 2017 Smart Structures and Systems, An International Jou Vol.20 No.2

Identification of damping characteristics is of significant importance for dynamic response analysis and condition assessment of structural systems. Damping is associated with the behavior of the energy dissipation mechanism. Identification of damping ratios based on the sensitivity of dynamic responses and the model updating technique is investigated with numerical and experimental investigations. The effectiveness and performance of using the sensitivity-based model updating method and vibration monitoring data for damping ratios identification are investigated. Numerical studies on a three-dimensional truss bridge model are conducted to verify the effectiveness of the proposed approach. Measurement noise effect and the initial finite element modelling errors are considered. The results demonstrate that the damping ratio identification with the proposed approach is not sensitive to the noise effect but could be affected significantly by the modelling errors. Experimental studies on a steel planar frame structure are conducted. The robustness and performance of the proposed damping identification approach are investigated with real measured vibration data. The results demonstrate that the proposed approach has a decent and reliable performance to identify the damping ratios.

Numerical and experimental verifications on damping identification with model updating and vibration monitoring data

Li, Jun,Hao, Hong,Fan, Gao,Ni, Pinghe,Wang, Xiangyu,Wu, Changzhi,Lee, Jae-Myung,Jung, Kwang-Hyo Techno-Press 2017 Smart Structures and Systems, An International Jou Vol.20 No.2

Identification of damping characteristics is of significant importance for dynamic response analysis and condition assessment of structural systems. Damping is associated with the behavior of the energy dissipation mechanism. Identification of damping ratios based on the sensitivity of dynamic responses and the model updating technique is investigated with numerical and experimental investigations. The effectiveness and performance of using the sensitivity-based model updating method and vibration monitoring data for damping ratios identification are investigated. Numerical studies on a three-dimensional truss bridge model are conducted to verify the effectiveness of the proposed approach. Measurement noise effect and the initial finite element modelling errors are considered. The results demonstrate that the damping ratio identification with the proposed approach is not sensitive to the noise effect but could be affected significantly by the modelling errors. Experimental studies on a steel planar frame structure are conducted. The robustness and performance of the proposed damping identification approach are investigated with real measured vibration data. The results demonstrate that the proposed approach has a decent and reliable performance to identify the damping ratios.

Enrichment of C17:0-rich saturated fatty acids from sheep tail fat for adjuvant therapy of non-small-cell lung cancer

Xiaoqi Yu,Xiaoyi Liu,Yuanli Li,Huimin He,Xinxin Pei,Tengfei Ma,Yuanyuan Chen,Yi Wang,Hongxia Li,Wenchu Lin,Changzhi Xu,Buchang Zhang 한국식품과학회 2024 Food Science and Biotechnology Vol.33 No.8

Heptadecanoic acid (C17:0), an odd-chain saturated fatty acid (OCSFA) in ruminant lipid, has been demonstrated to be potential for treating cancers. Our results also showed that sheep tail fat (STF) with higher level of C17:0-containing saturated fatty acids (SFAs) whereas lower level of oleic acid (C18:1), performed remarkable inhibition against non-small-cell lung cancer (NSCLC) cells. To enrich the content of C17:0, a C17:0-rich SFA concentrate (HRSC) was prepared from STF by solvent crystallization and urea complexation methods (hexane/STF = 3.5/1, 4 °C for 8 h, and 80% ethanol/urea/free fatty acids = 8/1/1, 4 °C for 6 h). The content of C17:0 was up from 3.02 to 6.34% and the recovery was 4.17%. Biological experiments showed that HRSC exerted better antiproliferative effect against NSCLC cells. Moreover, HRSC performed enhanced inhibitory effect in A549 cell xenograft mouse model. Therefore, HRSC has the potential to be applied in adjuvant therapy for NSCLC.