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Study of adaptive modulation and LDPC coding in multicarrier systems

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Journal of Systems Engineering and Electronics 2008年第1期19卷 39-45页

作者： Huo Yongqing peng Qicong shao Huaizong School of Communication and Information Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

An adaptive modulation （AM） algorithm is proposed and the application of the adapting algorithm together with low-density parity-check （LDPC） codes in multicarrier systems is investigated. The AM algorithm is based on minimizing the average bit error rate （BER） of systems, the combination of AM algorithm and LDPC codes with different code rates （half and three-fourths） are studied. The proposed AM algorithm with that of Fischer et al is compared. Simulation results show that the performance of the proposed AM algorithm is better than that of the Fischer＇s algorithm. The results also show that application of the proposed AM algorithm together with LDPC codes can greatly improve the performance of multicarrier systems. Results also show that the performance of the proposed algorithm is degraded with an increase in code rate when code length is the same.

关键词： multicarrier adaptive modulation low-density parity-check coding bit error rate.

Adaptive bit and power loading algorithm with low complexity in MIMO-OFDM systems

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Journal of Systems Engineering and Electronics 2008年第3期19卷 461-466页

作者： Huo Yongqing peng Qicong shao Huaizong School of Communication and Information Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P.R. China

Two adaptive power and bit loading algorithms to maximize the throughput of MIMO-OFDM systems in frequency selective fading environment are proposed. The two algorithms allocate bit based on maximizing the overall throughput. One algorithm allocates power based on guaranteeing that the bit error rate （BER） of each sub-carrier and the total allocated power remain below a target BER threshold and a power threshold, respectively; another one allocates power based on guaranteeing that the mean BER of sub-carriers and the total allocated power remain below a target BER threshold and a power threshold, respectively. The simulation results show that the proposed algorithms can achieve faster throughput with lower computational complexity, which indicates that the proposed algorithms are effective when compared to some existing algorithms.

关键词： MIMO-OFDM adaptive loading throughput BER.

Yield potential and nitrogen use efficiency of China's super rice

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Journal of Integrative Agriculture 2017年第5期16卷 1000-1008页

作者： WANG Fei peng shao-bing National Key Laboratory of Crop Improvement Huazhong Agricultural UniversityWuhan 430070P.R.China Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River Ministry of Agriculture/College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhan 430070P.R.China

In 1996, a mega project that aimed to develop rice varieties with super-high yield potential （super rice） was launched by the Ministry of Agriculture （MOA） in China using a combination of the ideotype approach and intersubspecific heterosis. Significant progress has been made in the last two decades, with a large number of super rice varieties being approved by the MOA and the national average grain yield being increased from 6.21 t ha^-1 in 1996 to 6.89 t ha^-1 in 2015. The increase in yield potential of super rice was mainly due to the larger sink size which resulted from larger panicles. Moreover, higher photosynthetic capacity and improved root physiological traits before heading contributed to the increase in sink size. However, the poor grain filling of the later-flowering inferior spikelets and the quickly decreased root activity of super rice during grain filling period restrict the achievement of high yield potential of super rice. Furthermore, it is widely accepted that the high yield potential of super rice requires a large amount of N fertilizer input, which has resulted in an increase in N consumption and a decrease in nitrogen use efficiency （NUE）, although it remains unclear whether super rice per se is responsible for the latter. In the present paper, we review the history and success of China＇s Super Rice Breeding Pro- gram, summarize the advances in agronomic and physiological mechanisms underlying the high yield potential of super rice, and examine NUE differences between super rice and ordinary rice varieties. We also provide a brief introduction to the Green Super Rice Project, which aims to diversify breeding targets beyond yield improvement alone to address global concerns around resource use and environmental change. It is hoped that this review will facilitate further improvement of rice production into the future.

关键词： super rice yield potential nitrogen use efficiency Green Super Rice

Zero Extension for the Biharmonic Equation

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Acta Mathematica Sinica,English Series 2018年第10期34卷 1549-1562页

作者： shao peng XU Shu Lin ZHOU School of Mathematical Sciences Peking University Beijing 100871 P. R. China LMAM School of Mathematical Sciences Peking University Beijing 100871 P. R. China

In this paper we present a necessary and sufficient condition to guarantee that the extended function of the solution by zero extension for the biharmonic equation in a smaller domain is still the solution of the corresponding extension problem in a larger domain. We prove the results under the frameworks of classical solutions and strong solutions.

关键词： Biharmonic zero extension

Imaging presentation of biliary adenofibroma:A case report

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World Journal of Clinical Cases 2022年第4期10卷 1366-1372页

作者： shao-peng Li peng Wang Ke-Xue Deng Department of Radiology The First Affiliated Hospital of University of Science and Technology of China(Southern District of Anhui Provincial Hospital)Hefei 230022Anhui ProvinceChina

BACKGROUND Biliary adenofibroma(BF)is a rare benign epithelial tumor with the possibility of malignant *** main pathological feature is a well-defined cystic or honeycomb *** has no specific clinical manifestations or laboratory and imaging findings;thus,it is easily misdiagnosed before *** report describes a case in which biliary cystadenoma was misdiagnosed preoperatively and BF was diagnosed *** imaging features,particularly the magnetic resonance imaging(MRI)features,were analyzed and *** SUMMARY A 68-year-old Chinese man was admitted to our hospital with a 2-mo history of abdominal *** admission to our hospital,laboratory examinations showed normal tumor marker concentrations and liver *** carcinoma was considered after contrast-enhanced ultrasound *** suggested the possibility of cystadenoma of the bile ***,postoperative pathological examination confirmed the diagnosis of *** local recurrence was found 1 mo after *** Our objective is to highlight the imaging diagnostic value of BF,especially on an MRI enhanced scan with gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid.

关键词： Biliary adenofibroma Magnetic resonance imaging Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid Misdiagnosis Case report

Effect of degree correlation on edge controllability of real networks

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Chinese Physics B 2020年第10期29卷 101-108页

作者： Shu-Lin Liu shao-peng Pang School of Electrical Engineering and Automation Qilu University of Technology(Shandong Academy of Science)Jinan 250353China

We use the controllability limit theory to study impact of correlation between in- and out-degrees (degree correlation) on edge controllability of real networks. Simulation results and analytic calculations show that the degree correlation plays an important role in the edge controllability of real networks, especially dense real networks. The upper and lower controllability limits hold for all kinds of real networks. Any edge controllability in between the limits is achievable by properly adjusting the degree correlation. In addition, we find that the edge dynamics in some real networks with positive degree correlation may be difficult to control, and explain the rationality of this anomaly based on the controllability limit theory.

关键词： complex network edge controllability degree correlation controllability limit

Environmental effect of vegetation restoration on degraded ecosystem in low subtropical China

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Journal of Environmental Sciences 2003年第4期15卷 514-519页

作者： peng shao-lin YANG Liu-chun LU Hong-fang South China Institute of Botany Chinese Academy of SciencesGuangzhou 510650China.

The environmental effect of degraded ecosystem's vegetation restoration in low subtropical China was studied. Results indicated that the vegetation recovery on degraded lands significantly ameliorates surrounding environment, increases species diversity, improves soil structure, raises soil fertility, enhances productivity, and promotes regional agricultural production and social economic development dramatically. Through the combining engineering and biological measures, the restoration of degraded ecosystem in low subtropical area is possible and economical. The restoration experience in Xiaoliang, Wuhua and other sites are valuable for other degraded subtropical area was introduced.

关键词： vegetation restoration degraded ecosystem low subtropical zone environment impact

Effects of the Antiferromagnetic Spin Coupling and Interdot Coulomb Repulsion on Kondo Effects in Serial Double Quantum Dots

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Chinese Physics Letters 2014年第4期31卷 139-142页

作者： LI Zeng-peng WU shao-Quan ZHAO Guo-Ping College of Physics and Electronic Engineering Siehuan Normal University Chengdu 610086

We theoretically study the effects of the antiferromagnetic （AF） spin coupling and the interdot Coulomb repulsion on the Kondo effects in serial double quantum dots by means of the slave-boson mean-field approximation. Our results indicate that in the weak coupling regime, the AF spin coupling strengthens the Kondo resonance, while the interdot Coulomb repulsion suppresses them for the equilibrium case. In the non-equilibrium case, the AF spin coupling strengthens the Kondo resonance only when J 〉 2.5TK0, while the interdot Coulomb repulsion does not suppress Kondo peaks. In the strong coupling regime, the bias voltage has no effects on the Kondo resonance in this system, and the AF spin coupling increases the height of Kondo peaks only when J 〈 2.5TK0. However, the inter-dot Coulomb repulsion suppresses the spin Kondo effect, which induces the orbit Kondo effect. Moreover, the relevant underlying physics of these problems are discussed.

关键词： ANTIFERROMAGNETIC resonance SPIN-spin interactions COULOMB potential KONDO effect QUANTUM dots

Effects of Nitrobenzene on Liver Antioxidant Defense System of Carassius auratus

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Chemical Research in Chinese Universities 2010年第2期26卷 204-209页

作者： shao peng YUAN Xing LIU Rui CAO Jian-ping College of Urban and Environmental Science Northeast Normal University Changchun 130024 P. R. China Research Institute of Environment Yangtze Delta Institute of Tsinghua University Jiaxing 314006 P. R. China

With superoxidedismutase（SOD）, catalase（CAT）, glutathione S-transferase（GST） and malondialdehyde （MDA） as characteristic indexes, the effects of nitrobenzene（NB） on the liver antioxidant defense system of Carassius auratus were studied under the indoors stimulant conditions, and the toxic mechanisms were discussed. The exposure concentrations of NB were 0.5, 1.0, 5.0 and 10.0 mg/L, and the exposure time was 5, 10 and 15 days, respectively. The results show that the stress responses of four antioxidant indexes in the fish liver to nitrobenzene were different. The SOD activity was firstly inhibited and then induced. The CAT and GST activities were mainly induced. The MDA content in the high concentration group showed a significant time-effect relationship. In addition, the changes of CAT and SOD activities were not synchronous, and GST played an important part in the detoxification process of nitrobenzene.

关键词： Nitrobenzene Superoxide dismutase Catalase Glutathione S-transferase Malondialdehyde