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Enhanced Harris Hawks Optimization Integrated with Coot Bird Optimization for Solving Continuous Numerical Optimization Problems

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Computer Modeling in Engineering & Sciences 2023年第11期137卷 1635-1675页

作者： Hao Cui Yanling Guo Yaning Xiao Yangwei Wang Jian Li Yapeng Zhang Haoyu Zhang College of Mechanical and Electrical Engineering Northeast Forestry UniversityHarbin150040China

Harris Hawks Optimization(HHO)is a novel meta-heuristic algorithm that imitates the predation characteristics of Harris Hawk and combines Lévy flight to solve complex multidimensional problems.Nevertheless,the basic HHO algorithm still has certain limitations,including the tendency to fall into the local optima and poor convergence accuracy.Coot Bird Optimization(CBO)is another new swarm-based optimization algorithm.CBO originates from the regular and irregular motion of a bird called Coot on the water’s surface.Although the framework of CBO is slightly complicated,it has outstanding exploration potential and excellent capability to avoid falling into local optimal solutions.This paper proposes a novel enhanced hybrid algorithm based on the basic HHO and CBO named Enhanced Harris Hawks Optimization Integrated with Coot Bird Optimization(EHHOCBO).EHHOCBO can provide higher-quality solutions for numerical optimization problems.It first embeds the leadership mechanism of CBO into the population initialization process of HHO.This way can take full advantage of the valuable solution information to provide a good foundation for the global search of the hybrid algorithm.Secondly,the Ensemble Mutation Strategy(EMS)is introduced to generate the mutant candidate positions for consideration,further improving the hybrid algorithm’s exploration trend and population diversity.To further reduce the likelihood of falling into the local optima and speed up the convergence,Refracted Opposition-Based Learning(ROBL)is adopted to update the current optimal solution in the swarm.Using 23 classical benchmark functions and the IEEE CEC2017 test suite,the performance of the proposed EHHOCBO is comprehensively evaluated and compared with eight other basic meta-heuristic algorithms and six improved variants.Experimental results show that EHHOCBO can achieve better solution accuracy,faster convergence speed,and a more robust ability to jump out of local optima than other advanced optimizers in most test cases.Finally,EHHOCBOis applied to ad

关键词： Harris hawks optimization coot bird optimization hybrid ensemblemutation strategy refracted opposition-based learning

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A hybrid Offline-Online Approach to Adaptive Downlink Resource Allocation Over LTE

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IEEE/CAA Journal of Automatica Sinica 2019年第3期6卷 766-777页

作者： Satish Kumar Rajesh Devaraj Arnab Sarkar IEEE the Department of Computer Science and Engineering IIT Guwahati

Radio resource management mechanisms in current and future wireless networks is expected to face an enormous challenge due to the ever increasing demand for bandwidth and latency sensitive applications on mobile devices. This is because an optimal resource allocation scheme which attempts to multiplex the available bandwidth in order to maximize Quality of service(QoS), will pose an exponential computational burden at eNodeB. In order to minimize such computational overhead, this work proposes a hybrid offline-online resource allocation strategy which effectively allocates all the available resources among flows such that their QoS requirements are satisfied. The flows are firstly classified into priority buckets based on real-time criticality factors. During the offline phase, the scheduler attempts to maintain the system load within a pre-specified safe threshold value by selecting an appropriate number of buckets. This offline selection procedure makes use of supervisory control theory of discrete event systems to synthesize an offline scheduler. Next, we have devised an online resource allocation strategy which runs on top of the offline policy and attempts to minimize the impact of the inherent variability in wireless networks. Simulation results show that the proposed scheduling framework is able to provide satisfactory QoS to all end users in most practical scenarios.

关键词： Discrete event systems (DES) hybrid scheduling long term evolution (LTE) quality of service (QoS) radio resource management supervisory control

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ZmMs30 Encoding a Novel GDSL Lipase Is Essential for Male Fertility and Valuable for hybrid Breeding in Maize

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Molecular Plant 2019年第3期12卷 343-359页

作者： Xueli An Zhenying Dong Youhui Tian Ke Xie Suowei Wu Taotao Zhu Danfeng Zhang Van Zhou Canfang Niu Biao Ma Quancan Hou Jianxi Bao Simiao Zhang Ziwen Li Yanbo Wang Tingwei Yan Xiaojing Sun Yuwen Zhang Jinping Li Xiangyuan Wan Biology and Agriculture Research Center University of Science and Technology BeijingBeijing 100024China Beijing Engineering Laboratory of Main Crop Bio-Tech Breeding Beijing International Science and Technology Cooperation Base of Bio-Tech BreedingBeijing Solidwill Sci-Tech Co.Ltd.Beijing 100192China

Genic male sterility (GMS) is very useful for hybrid vigor utilization and hybrid seed production. Although a large number of GMS genes have been identified in plants, little is known about the roles of GDSL lipase members in anther and pollen development. Here, we report a maize GMS gene, ZmMs30, which encodes a novel type of GDSL lipase with diverged catalytic residues. Enzyme kinetics and activity assays show that ZmMs30 has lipase activity and prefers to substrates with a short carbon chain. ZmMs30 is specifically expressed in maize anthers during stages 7-9. Loss of ZmMs30 function resulted in defective anther cuticle, irregular foot layer of pollen exine, and complete male sterility. Cytological and lipidomics analyses demonstrate that ZmMs30 is crucial for the aliphatic metabolic pathway required for pollen exine formation and anther cuticle development. Furthermore, we found that male sterility caused by loss of ZmMs30 function was stable in various inbred lines with different genetic background, and that it didn't show any negative effect on maize heterosis and production, suggesting that ZmMs30 is valuable for crossbreeding and hybrid seed production. We then developed a new multi-control sterility system using ZmMs30 and its mutant line, and demonstrated it is feasible for generating desirable GMS lines and valu. able for hybrid maize seed production. Taken together, our study sheds new light on the mechanisms of anther and pollen development, and provides a valuable male-sterility system for hybrid breeding maize.

关键词： ZmMs30f GDSL lipase multi-control sterility (MCS) system hybrid seed production maize

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hybrid Precoder and Combiner Design with Finite Resolution PSs for mmWave MIMO Systems

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China Communications 2019年第2期16卷 95-104页

作者： Ran Zhang Weixia Zou Ye Wang Mingyang Cui Key Lab of Universal Wireless Communications MOEBeijing University of Posts and Telecommunications State Key Lab.of Millimeter Waves Southeast University

hybrid precoding and combining have been considered as a promising technology, which can provide a compromise between hardware complexity and system performance in millimeter wave multiple-input multiple-output systems. However, most existing hybrid precoder and combiner designs generally assume that infinite resolution phase shifters(PSs) are used to produce the analog beamformers. In a practical scene, the design with accurate PSs can lead to high hardware cost and power consumption. In this paper, we investigate the hybrid precoder and combiner design with finite resolution PSs in millimeter wave systems. We employ alternate optimization as the main strategy to jointly design analog precoder and combiner. In addition, we propose a low complexity algorithm, where the analog beamformers are implemented only by finite resolution PSs to maximize spectral efficiency. Then, the digital precoder and combiner are designed based on the obtained analog beamformers to improve the spectral efficiency. Finally, simulation results and mathematical analysis show that the proposed algorithm with low-resolution PSs can achieve near-optimal performance and have low complexity.

关键词： millimeter wave multiple-input multiple-output finite resolution phase shifters hybrid precoding alternate optimization

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hybrid TaON/LaTiO_(2)N photoelectrode for water oxidation

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Transportation Safety and Environment 2019年第3期1卷 212-219页

作者： Pengda An Baopeng Yang Ning Zhang Hongmei Li Min Liu State Key Laboratory of Powder Metallurgy Shenzhen Research InstituteSchool of Physics and ElectronicsCentral South University932 South Lushan RoadChangshaHunan 410083P.R.China School of Materials Science and Engineering Central South University932 South Lushan RoadChangshaHunan 410083P.R.China

Efficient and stable photoelectrodes for water oxidation are highly desirable in the field of photoelectrochemical(PEC)water splitting.However,photoelectrodes with low externally applied bias usually exhibit weak photocurrent and vice versa.Herein,novel and efficient CoO_(x)-TaON/LTON composite photoanodes have been successfully prepared by a microwave assisted method followed with a particle transfer procedure.The obtained photoanode generated an anodic photocurrent of∼7.2 mA cm^(−2) at 1.2 V_(RHE) and initiated the anodic photourrent at∼0.5 V_(RHE).The HC-STH of the composite photoelectrode reached 1.0%at 1.2 V_(RHE).Further,stoichiometric oxygen and hydrogen are stably produced on the photoanode and the counter electrode with a Faraday efficiency of unity for 2 h.

关键词： TaON LaTiO_(2)N hybrid Water oxidation

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hybrid and Full-Digital Beamforming in mmWave Massive MIMO Systems: A Comparison Considering Low-Resolution ADCs

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China Communications 2019年第6期16卷 91-102页

作者： Wence Zhang Xiaoxuan Xia Yinkai Fu Xu Bao School of Computer Science and Communications Engineering Jiangsu UniversityZhenjiang 212013China National Mobile Communications Research Lab. Southeast UniversityNanjing 210089China

In a millimeter-wave(mmWave)Massive multiple-input multiple-output(MIMO)systems,full-digital beamforming(i.e.,connecting each antenna with a specific radio-frequency(RF)chain)becomes inefficient due to the hardware cost and power consumption.Therefore,hybrid analog and digital transceiver where the number of RF chains are much smaller than that of the antennas has drawn great research interest.In this work,we investigate the use of low-resolution analog-to-digital converters(ADCs)in the uplink of multi-user hybrid and full-digital mmWave Massive MIMO systems.To be specific,we compare the performance of full-digital minimum mean square error(MMSE)and hybrid MMSE beamforming in both sum rates and energy efficiency.Accurate approximations of sum rates and energy efficiency are provided for both schemes,which captures the dominant factors.The analytical results show that full-digital beamforming outperforms hybrid beamforming in terms of sum rates and requires only a small portion(γ)of antennas used by hybrid beamforming to achieve the same sum rates.We given sufficient condition for full-digital beamforming to outperform hybrid beamforming in terms of energy efficiency.Moreover,an algorithm is proposed to search for the optimal ADC resolution bits.Numerical results demonstrate the correctness of the analysis.

关键词： hybrid massive MIMO mmWave MMSE low-resolution ADCs

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hybrid Precoding for mm Wave Massive MIMO Systems with Different Antenna Arrays

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China Communications 2019年第10期16卷 45-55页

作者： Qingfeng Ding Yuqian Deng Xinpeng Gao Mengxia Liu School of Electrical and Automation Engineering East China Jiaotong University

In this paper, the performance of hybrid precoding is investigated for mmWave massive MIMO systems with different antenna arrays. The hybrid precoding with partially connected architecture (PCA) is adopted. The spectral efficiency (SE) and received energy efficiency (EE) are investigated by considering four types of antenna arrays, including uniform linear array (ULA), uniform rectangular planar array (URPA), uniform hexagonal planar array (UHPA), and uniform circular planar array (UCPA), respectively. We focus on analysis at the antenna response vector and utilize the idea of orthogonal matching pursuit algorithm to seek the optimal hybrid precoder. Furthermore, the trade-off of precoding architectures is studied between SE and received EE. Simulation results show that if the uniform planar array antenna is more concentrated, the SE and receive EE will be higher. Considering SE and received EE, the performance of planar arrays outperform linear array. There exist different optimal radio-frequency chain numbers to maximize the SE for planar array and linear array. In addition, the PCA can achieve relatively higher received EE while the SE is close to the fully connected architecture and the full digital architecture.

关键词： massive MIMO mmWave hybrid precoding array antenna spectral efficiency

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Very-High Color Rendering Index hybrid White Organic Light-Emitting Diodes with Double Emitting Nanolayers

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Nano-Micro Letters 2014年第4期6卷 335-339页

作者： Baiquan Liu Miao Xu Lei Wang Hong Tao Yueju Su Dongyu Gao Linfeng Lan Jianhua Zou Junbiao Peng Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and Devices South China University of Technology New Vision Opto-Electronic Technology Co. Ltd

A very-high color rendering index white organic light-emitting diode(WOLED) based on a simple structure was successfully fabricated. The optimized device exhibits a maximum total efficiency of 13.1 and 5.4 lm/W at 1,000 cd/m2. A peak color rendering index of 90 and a relatively stable color during a wide range of luminance were obtained. In addition, it was demonstrated that the 4,40,400-tri(9-carbazoyl) triphenylamine host influenced strongly the performance of this WOLED.These results may be beneficial to the design of both material and device architecture for high-performance WOLED.

关键词： White light hybrid Color rendering index Organic light-emitting diodes Double emitting nanolayers

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Understanding and breaking down the reproductive barrier between Asian and African cultivated rice: a new start for hybrid rice breeding

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Science China(Life Sciences) 2019年第8期62卷 1114-1116页

作者： Yidan Ouyang National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan) Huazhong Agricultural University

Oryza sativa and O.glaberrima,commonly known as Asian and African cultivated rice,are two domesticated rice species in Oryza genus.Asian cultivated rice may produce higher yields with better quality,whereas African cultivated rice shows a wide range of tolerance to abiotic and biotic stresses.Interspecific hybrids between O.sativa and O.glaberrima would show strong heterosis and thus increasing production because of their distant genetic diversity and complementary agronomic traits.However,reduced fertility is observed in hybrids from interspecific crosses;this hinders further utilization of rice heterosis in agriculture production.Such severe abnormal development of gametophytes in hybrids is caused by reproductive isolation,a process that prevents individuals of genetically diverged groups from mating,survival or producing fertile offspring.

关键词： TPR Understanding and breaking down the reproductive barrier between Asian and African cultivated rice a new start for hybrid rice breeding

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hybrid microsystem with functionalized silicon substrate and PDMS sample operating microchannel: A reconfigurable microfluidics scheme

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Science China(Technological Sciences) 2010年第8期53卷 2272-2277页

作者： LEI YinHua 1 ,XIE Fei 1 ,WANG Wei 1,2 ,WANG HaiBin 3 &LI ZhiHong 1,2 1 Institute of Microelectronics,Peking University,Beijing 100871,China 2National Key Laboratory of Science and Technology on Micro/Nano Fabrication,Beijing 100871,China 3 No.302 Hospital,Beijing 100039,China Institute of Microelectronics Peking University Beijing China National Key Laboratory of Science and Technology on Micro/Nano Fabrication Beijing China No. 302 Hospital Beijing China

A hybrid microsystem with separately functioned temperature controlling substrate and sample operating fluidic microchannel was developed to demonstrate a reconfigurable microfluidics scheme.The temperature controlling substrate integrated a micro heater and a temperature sensor by using traditional silicon-based micromechanical system(MEMS)technique,which guaranteed high performance and robust reliability for repeatable usage.The sample operating fluidic microchannel was prepared by poly-(dimethylsiloxane) (PDMS)based soft lithography technique,which made it cheap enough for disposable applications.The PDMS microchannel chip was attached to the temperature controlling substrate for reconfigurable thermal applications.A thin PDMS film was used to seal the microchannel and bridge the functionalized substrate and the sample inside the channel,which facilitated heat transferring and prevented sample contaminating the temperature controlling substrate.Demonstrated by a one dimensional thermal resistance model,the thin PDMS film was important for the present reconfiguration applications.Thermal performance of this hybrid microsystem was examined,and the experimental results demonstrated that the chip system could work stably over hours with temperature variation less than 0.1oC.Multiple PDMS microchannel chips were tested on one heating substrate sequentially with a maximum intra-chip temperature difference of 1.0oC.DNA extracted from serum of a chronic hepatitis B virus(HBV)patient was amplified by this hybrid microsystem and the gel electrophoresis result indicated that the present reconfigurable microfluidic scheme worked successfully.

关键词： reconfigurable microfluidics hybrid microdevice thin PDMS film

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