Hybrid No-Reference Video Quality Assessment Focusing on Codec Effects

( Xingang Liu ),( Min Chen ),( Tang Wan ),( Chen Yu ) 한국인터넷정보학회 2011 KSII Transactions on Internet and Information Syst Vol.5 No.3

Currently, the development of multimedia communication has progressed so rapidly that the video program service has become a requirement for ordinary customers. The quality of experience (QoE) for the visual signal is of the fundamental importance for numerous image and video processing applications, where the goal of video quality assessment (VQA) is to automatically measure the quality of the visual signal in agreement with the human judgment of the video quality. Considering the codec effect to the video quality, in this paper an efficient non-reference (NR) VQA algorithm is proposed which estimates the video quality (VQ) only by utilizing the distorted video signal at the destination. The VQA feature vectors (FVs) which have high relationships with the subjective quality of the distorted video are investigated, and a hybrid NR VQA (HNRVQA) function is established by considering the multiple FVs. The simulation results, testing on the SDTV programming provided by VCEG Phase I, show that the proposed algorithm can represent the VQ accurately, and it can be used to replace the subjective VQA to measure the quality of the video signal automatically at the destinations.

Effects of temperature on the ratcheting behavior of pressurized 90 elbow pipe under force controlled cyclic loading

Xiaohui Chen,Xingang Wang,Xu Chen 국제구조공학회 2017 Smart Structures and Systems, An International Jou Vol.19 No.5

Ratcheting behavior of 90 elbow piping subject to internal pressure 20 MPa and reversed bending 20 kN was investigated using experimental method. The maximum ratcheting strain was found in the circumferential direction of intrados. Ratcheting strain at flanks was also very large. Moreover, the effect of temperature on ratcheting strain of 90 elbow piping was studied through finite element analysis, and the results were compared with room condition (25). The results revealed that ratcheting strain of 90 elbow piping increased with increasing temperature. Ratcheting boundary of 90 elbow piping was determined by Chaboche model combined with C-TDF method. The results revealed that there was no relationship between the dimensionless form of ratcheting boundary and temperature.

Constitutive model for ratcheting behavior of Z2CND18.12N austenitic stainless steel under non-symmetric cyclic stress based on BP neural network

Xingang Wang,Xiaohui Chen,Mingming Yan,Miaoxin Chang 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.28 No.5

The specimens made by Z2CND18.12N austenitic stainless steel were conducted on a 100 kN closed loop servo hydraulic tension-compression testing machine with a digital controller. Uniaxial tension and uniaxial ratcheting effect tests were carried out at 25°C. Moreover, Uniaxial tension tests were conducted at 150°C, 250°C and 350°C. Based on these experimental data, the prediction models of stress-strain curve and the relationship of ratcheting strain and number of cycles were established by the algorithm principle of BP neural network. The results indicated that the predicted results of neural network model were in well agreement with experimental data. It was found that the BP neural network model had high validity and accuracy.

Evaluation of limit load analysis for pressure vessels — Part II: Robust methods

Xiaohui Chen,Bingjun Gao,Xingang Wang 국제구조공학회 2017 Steel and Composite Structures, An International J Vol.23 No.1

Determining limit load for a pressure bearing structure using elastic-plastic finite element analysis was computationally very expensive. A series of robust methods using elastic modulus adjustment techniques (EMAP) to identify the limit load directly were proposed. The numerical implementation of the robust method had the potential to be an attractive alternative to elastic-plastic finite element analysis since it was simple, and required less computational effort and computer storage space. Another attractive feature was that the method provided a go/no go criterion for the limit load, whereas the results of an elastic-plastic analysis were often difficult to interpret near the limit load since it came from human sources. To explore the performance of the method further, it was applied to a number of configurations that include two-dimensional and threedimensional effects. In this study, limit load of cylinder with nozzle was determined by the robust methods.

Evaluation of limit load analysis for pressure vessels ‒ Part I: Linear and nonlinear methods

Xiaohui Chen,Bingjun Gao,Xingang Wang 국제구조공학회 2016 Steel and Composite Structures, An International J Vol.22 No.6

Limit load of pressure bearing structures was reviewed in this article. By means of the finite element analysis, limit load of pressurized cylinder with nozzle was taken as an example. Stress classification method and Elastic-plastic finite element analysis combining with limit load determination methods were used to determine limit load of cylinder with nozzle. Comparison of limit load determined by different methods, the results indicated that limit load determined by linearization method was the smallest. Limit load determined by twice elastic slope criterion was the nearest than experimental results. Elastic-plastic finite element analysis had comparably computational precision, but required time consuming. And then the requirements of computer processing and storage capacity by power system became higher and higher. Most of criteria for limit load estimation included any human factors based on a certain substantive characteristics of experimental results. The reasonable criterion should be objective and operational.

Dynamic QTL Analysis of Rice Protein Content and Protein Index Using Recombinant Inbred Lines

Leina Zheng,Wenwei Zhang,Xingang Chen,Jing Ma,Weiwei Chen,Zhigang Zhao,Huqu Zhai,Jianmin Wan 한국식물학회 2011 Journal of Plant Biology Vol.54 No.5

Protein content (PC) and protein index (PI) play important roles in determining nutritional quality in rice (Oryza sativa L.). We used 71 lines derived from “Asominori/IR24” to analyze the developmental behavior of PC and PI through unconditional and conditional QTL mapping methods. In all, 10 unconditional QTLs and 6conditional QTLs for PC, and 11 unconditional QTLs and 9conditional QTLs for PI, were identified at four stages of grain filling. More were identified in the first three stages than at the final stage. Temporal patterns of gene expression for PC and PI differed over time, with several QTLs being expressed across two or three stages but many being expressed at only one stage. Some of these QTLs were closely linked with maturity QTLs reported previously. Many QTLs for PC and PI were co-localized, supporting the significant correlation found between PC and PI. Our results suggest that dynamic QTL mapping might be a valid means for revealing more genetic information about protein accumulations during seed development.

Neoadjuvant Chemotherapy-Guided Bladder-Sparing Treatment for Muscle-Invasive Bladder Cancer: Results of a Pilot Phase II Study

Hongzhe Shi,Wen Zhang,Xingang Bi,Dong Wang,Zejun Xiao,Youyan Guan,Kaopeng Guan,Jun Tian,Hongsong Bai,Linjun Hu,Chuanzhen Cao,Weixing Jiang,Zhilong Hu,Jin Zhang,Yan Chen,Shan Zheng,Xiaoli Feng,Changlin 대한암학회 2021 Cancer Research and Treatment Vol.53 No.4

Purpose Reduced quality of life after cystectomy has made bladder preservation a popular research topic for muscle-invasive bladder cancer (MIBC). Previous research has indicated significant tumor downstaging after neoadjuvant chemotherapy (NAC). However, maximal transurethral resection of bladder tumor (TURBT) was performed before NAC to define the pathology, impacting the real evaluation of NAC. This research aimed to assess real NAC efficacy without interference from TURBT and apply combined modality therapies guided by NAC efficacy. Materials and Methods Patients with cT2-4aN0M0 MIBC were confirmed by cystoscopic biopsy and imaging. NAC efficacy was assessed by imaging, urine cytology, and cystoscopy with multidisciplinary team discussion. Definite responders (≤ T1) underwent TURBT plus concurrent chemoradiotherapy. Incomplete responders underwent radical cystectomy or partial cystectomy if feasible. The primary endpoint was the bladder preservation rate. Results Fifty-nine patients were enrolled, and the median age was 63 years. Patients with cT3-4 accounted for 75%. The median number of NAC cycles was three. Definite responders were 52.5%. The complete response (CR) was 10.2%, and 59.3% of patients received bladder-sparing treatments. With a median follow-up of 44.6 months, the 3-year overall survival (OS) was 72.8%. Three-year OS and relapse-free survival were 88.4% and 60.0% in the bladder-sparing group but only 74.3% and 37.5% in the cystectomy group. The evaluations of preserved bladder function were satisfactory. Conclusion After stratifying MIBC patients by NAC efficacy, definite responders achieved a satisfactory bladder-sparing rate, prognosis, and bladder function. The CR rate reflected the real NAC efficacy for MIBC. This therapy is worth verifying through multicenter research.

Arm Balance Control Scheme of Novel Isolated Modular Multilevel Converter (I-MMC)

Lin. Lin,Qi. Chen,Xingang. Wu,Chuang. Liu,Jinming. Li,Dehao. Kong 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

This paper introduces an isolated modular multilevel converter (I-MMC) structure which can transport the energy power from LVDC to HVDC and HVAC with single-stage, and the arm balance control strategy. The paper also analyzes the reason of leading to the unbalance in arm, establish the relevant model, and propose the unbalance control strategy of the arm. Finally, the method is verified by simulation and experiment.

High-Frequency Isolated Medium-Voltage AC Grid-connected PV Power Generation System Structure based on DC Bus Collection

Lin. Lin,Qi. Chen,Xingang. Wu,Chuang. Liu,Haoran. Zhang,Dongfeng. Yang 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

This paper proposes an isolated mediumvoltage AC grid-connected PV power generation system structure based on DC bus collection with high-frequency link concept. The proposed system structure consists of centralized photovoltaic power plant, inverter unit based on isolated bridge converter (I-BC), and capacitor at the junction of dc bus. PV plant is divided into many arrays, each PV array is connected in parallel with each phase inverter unit. Inverter unit is composed of two I-BC. Compare with conventional two-stage PV inverter, I-BC can totally eliminate the individual DC-link capacitors at the highvoltage side, which leads to extremely reduced system volume and voltage-balancing control between individual capacitors. Second harmonic power oscillations seen in typical system structure can also be eliminated or reduced through use of the proposed system. This paper presents the analysis and operation of the proposed PV system structure with experimental results on a scaled-down laboratory.