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Modified Omega-K algorithm for processing helicopter-borne frequency modulated continuous waveform rotating synthetic aperture radar data

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Journal of Systems Engineering and Electronics 2015年第3期26卷 476-485页

作者： Dong li Guisheng liao Yong liao lisheng Yang Key Laboratory of Aerocraft Tracking Telemetering & Command and Communication Ministry of EducationChongqing University National Lab of Radar Signal Processing Xidian University

With appropriate geometry configuration, helicopter- borne rotating synthetic aperture radar （ROSAR） can break through the limitations of monostatic synthetic aperture radar （SAR） on forward-looking imaging. With this capability, ROSAR has extensive potential applications, such as self-navigation and self-landing. Moreover, it has many advantages if combined with the frequency modulated continuous wave （FMCW） technology. A novel geometric configuration and an imaging algorithm for helicopter-borne FMCW-ROSAR are proposed. Firstly, by per- forming the equivalent phase center principle, the separated trans- mitting and receiving antenna system is equalized to the case of system configuration with antenna for both transmitting and receiving signals. Based on this, the accurate two-dimensional spectrum is obtained and the Doppler frequency shift effect in- duced by the continuous motion of the platform during the long pulse duration is compensated. Next, the impacts of the velocity approximation error on the imaging algorithm are analyzed in de- tail, and the system parameters selection and resolution analysis are presented. The well-focused SAR image is then obtained by using the improved Omega-K algorithm incorporating the accurate compensation method for the velocity approximation error. FJnally, correctness of the analysis and effectiveness of the proposed al- gorithm are demonstrated through simulation results.

关键词： helicopter-borne rotating synthetic aperture radar(ROSAR) frequency modulated continuous wave (FMCW) improved Omega-K algorithm two-dimensional spectrum.

A modified radiofrequency ablation approach for treating distant lymph node metastasis in two patients with late-stage cancer

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Chinese Journal of Cancer 2013年第10期32卷 567-570页

作者： Ru-hai Zou Qi-Jiong li Ji-liang Qiu Ya-Di liao Yun-Fei Yuan An-Hua li State Key Laboratory of Oncology in South China Department of Ultrasound Sun Yat-sen University Cancer Center Department of Hepatobiliary Oncology Sun Yat-sen University Cancer Center

Patients with late-stage cancer commonly have distant lymph node metastasis;however,poor health often contraindicates surgical *** the quality of life and overall survival for these patients are low,there is neither a consensus nor a guide for *** technique and surrounding tissue damage are two possible reasons for limited study of radiofrequency ablation in patients with superficial distant lymph node ***,we report two patients treated successfully with ultrasound-guided radiofrequency ablation for superficial distant lymph node *** these patients,deionized water was injected to the surrounding tissues of the lymph node to decrease heat *** from these patients suggest that radiofrequency ablation may play an important role in the treatment of patients with distant lymph node metastasis.

关键词：手术治疗射频消融淋巴结癌症晚期组织损伤去离子水患者

Understanding and identifying latent data races cross-thread interleaving

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Frontiers of Computer Science 2015年第4期9卷 524-539页

作者： Long ZHEN~ Xiaofei liao Song WU Xuepeng FAN hai JIN Services Computing Technology and System Laboratory Cluster and Grid Computing Laboratory School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

Data races are ubiquitous in multi-threaded ap- plications, but they are by no means easy to detect. One of the most important reasons is the complexity of thread in- terleavings. A volume of research has been devoted to the interleaving-insensitive detection. However, all the previous work focuses on the uniform detection （unknown to the char- acteristics of thread interleavings）, thereby making the detec- tion defective in either reporting false positives or suffering from prohibitive overhead. To cope with the problem above, we propose an efficient, precise, and sound step-by-step res- olution based on the characteristics of thread interleavings. We first try to tease apart the categories of thread interleav- ings from the several typical sources arising from the lock synchronizations. We then conduct a brief study and find a new and complex pattern the previous work cannot detect. It is also revealed that the simple pattern with the majority of thread interleavings can be resolved by a simple processing to achieve a big profit for the previous reordering-based design. Our final experimental results demonstrate the effectiveness of our empiricism-based approach, and show that 51.0% of execution time and 52.3 % of trace size arising from the state- of-the-art reordering technique can be saved through a quick filtering of the simple pattern with a negligible （4.45%） per- formance overhead introduced on-the-fly.

关键词： data race happens-before thread interleaving

Joint Multi-Domain Channel Estimation Based on Sparse Bayesian Learning for OTFS System

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China Communications 2023年第1期20卷 14-23页

作者： Yong liao Xue li School of Microelectronics and Communication Engineering Chongqing UniversityChongqing 400044China

Since orthogonal time-frequency space(OTFS)can effectively handle the problems caused by Doppler effect in high-mobility environment,it has gradually become a promising candidate for modulation scheme in the next generation of mobile ***,the inter-Doppler interference(IDI)problem caused by fractional Doppler poses great challenges to channel *** avoid this problem,this paper proposes a joint time and delayDoppler(DD)domain based on sparse Bayesian learning(SBL)channel estimation ***,we derive the original channel response(OCR)from the time domain channel impulse response(CIR),which can reflect the channel variation during one OTFS *** with the traditional channel model,the OCR can avoid the IDI *** that,the dimension of OCR is reduced by using the basis expansion model(BEM)and the relationship between the time and DD domain channel model,so that we have turned the underdetermined problem into an overdetermined ***,in terms of sparsity of channel in delay domain,SBL algorithm is used to estimate the basis coefficients in the BEM without any priori information of *** simulation results show the effectiveness and superiority of the proposed channel estimation algorithm.

关键词： OTFS sparse Bayesian learning basis expansion model channel estimation

On the periodic solutions of the three-body problem

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National Science Review 2019年第6期6卷 1070-1071页

作者： Shijun liao Xiaoming li Advanced Center of Computing School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong University School of Physics and Astronomy Shanghai Jiao Tong University MOE Key Laboratory of Disaster Forecast and Control in Engineering School of Mechanics and Construction Engineering Jinan University

The motion of three bodies that attract each other by universal gravitation was first investigated by Newton [1] and was reconsidered by many great mathematicians and scientists, including Euler, Lagrange, Poincaré [2] and Hilbert. The famous three-body problem has had a great influence on physics, mathematics and non-linear dynamics. It has led to a new

关键词： On the periodic solutions of the three-body problem

Hardy space estimates for bi-parameter littlewood-Paley square functions

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Frontiers of Mathematics in China 2020年第2期15卷 333-349页

作者： Fanghui liao Zhengyang li School of Mathematics and Computational Sciences Xiangtan UniversityXiangtan 411105China School of Mathematics and Computational Sciences Hunan University of Science and TechnologyXiangtan 411201China

Suppose that g(f)are bi-parameter littlewood-Paley square functions which were introduced by *** is known that the L^2(R^n×R^m)boundedness and the H1(R^n×R^m)-L1(R^n×R^m)boundedness of g(f)have been proved by *** and by *** and ***,*** this paper,we apply the vector-valued theory,the atomic decomposition of product Hardy spaces,and Journe’s covering lemma to show that g(f)are bounded from H^p(R^n×R^m)to Lp(R^n×R^m)with p smaller than 1.

关键词： Hardy space littlewood-Paley square function Journe’s covering lemma atomic decomposition

A Survey of Non-Volatile Main Memory Technologies:State-of-the-Arts,Practices,and Future Directions

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Journal of Computer Science & Technology 2021年第1期36卷 4-32页

作者： hai-Kun liu Di Chen hai Jin Xiao-Fei liao Binsheng He Kan Hu Yu Zhang National Engineering Research Center for Big Data Technology and System Huazhong University of Science and TechnologyWuhan 430074China Services Computing Technology and System Laboratory Huazhong University of Science and Technology Wuhan 430074China Cluster and Grid Computing Laboratory Huazhong University of Science and TechnologyWuhan 430074China School of Computing Science and Technology Huazhong University of Science and TechnologyWuhan 430074China School of Computing National University of SingaporeSingapore 117418Singapore

Non-Volatile Main Memories (NVMMs) have recently emerged as a promising technology for future memory systems. Generally, NVMMs have many desirable properties such as high density, byte-addressability, non-volatility, low cost, and energy efficiency, at the expense of high write latency, high write power consumption, and limited write endurance. NVMMs have become a competitive alternative of Dynamic Random Access Memory (DRAM), and will fundamentally change the landscape of memory systems. They bring many research opportunities as well as challenges on system architectural designs, memory management in operating systems (OSes), and programming models for hybrid memory systems. In this article, we revisit the landscape of emerging NVMM technologies, and then survey the state-of-the-art studies of NVMM technologies. We classify those studies with a taxonomy according to different dimensions such as memory architectures, data persistence, performance improvement, energy saving, and wear leveling. Second, to demonstrate the best practices in building NVMM systems, we introduce our recent work of hybrid memory system designs from the dimensions of architectures, systems, and applications. At last, we present our vision of future research directions of NVMMs and shed some light on design challenges and opportunities.

关键词： non-volatile memory persistent memory hybrid memory systems memory hierarchy

Impact Evaluation of CONSORT and STRICTA Guidelines on Reporting Quality for Randomized Controlled Trials of Acupuncture Conducted in China

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Chinese Journal of Integrative Medicine 2017年第1期23卷 10-17页

作者： LU li-ming HE Jun ZENG Jing-chun liao Mu-xi JIA Chao PAN hai-hua Key Unit of Methodology in Clinical Research Guangdong Provincial Hospital of Chinese MedicineGuangzhou 510120China Department of Acupuncture First Affiliated HospitalGuangzhou University of Chinese MedicineGuangzhou 510405China Department of Acupuncture Guangzhou University of Chinese Medicine.Guangzhou 510405.China

Objective： To evaluate and compare the reports＇ qualities of acupuncture randomized controlled trials （RCTs） conducted in China before and after the implementation of two guidelines, i.e., the Consolidated Standards of Reporting Trials （CONSORT） statement and the Standards for Reporting Interventions in Controlled Trials of Acupuncture （STRICTA）. Methods： Proportions of studies that reported CONSORT and STRICTA items were compared for the years before and after implementation of these two guidelines. In addition, the total score of each item＇s reporting were calculated and reported differences during different date ranges were compared. Results： For CONSORT items （maximum score 8）, there was evidence of a slight improvement in reporting between 1994-1995 and 1999-2000 combined （2.5 ± 0.6） and 2004-2006 and 2009-2010 combined （3.0 ± 0.9; difference 0.4, 95% confidence interval, 0.3 to 0.6, P〈0.01）. For STRICTA items （maximum score 17）, there was evidence that a slight improvement in reporting between 1994-1995 and 1999-2000 combined （8.6±2.1） and 2004-2005 and 2009-2010 combined （10.1 ±1.8; difference 1.5, 95% confidence interval, 1.1 to 1.9, P〈0.01）. Conclusion： Quality of reporting for RCTs of acupuncture treatment conducted in China have generally improved since the introduction of the STRICTA and CONSORT guidelines.

关键词： acupuncture quality of reporting randomized controlled trials Consolidated Standardsof Reporting Trials (CONSORT) statement Standards for Reporting Interventions in Controlled Trials ofAcupuncture (STRICTA)

Pattern transition of two-dimensional Faraday waves at an extremely shallow depth

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Science China(Physics,Mechanics & Astronomy) 2016年第11期59卷 58-60页

作者： XiaoChen li XiaoMing li ShiJun liao School of Naval Architecture Ocean and Civil EngineeringShanghai Jiaotong UniversityShanghai 200240China Collaborative Innovative Center for Advanced Ship and Deep-Sea Exploration Shanghai 200240China State Key Laboratory of Ocean Engineering Shanghai 200240China

In this paper, we experimentally investigate the pattern transition of two-dimensional Faraday waves at an extremely shallow depth in a Hele-Shaw cell. Several patterns of Faraday waves are observed, which have some significant differences in wave profile,wave height and wave length. It is found that, in a wide range of the forcing frequency f, there always exists a region of the acceleration amplitude A, in which there exist the so-called hysteretic jumps between different patterns of Faraday waves. All of these experimental observations could enrich our knowledges about the Faraday waves and would be helpful to the further theoretical studies on the related topic in future.

关键词： Faraday waves extremely shallow water experimental observation