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Joint Optimization Scheme Based on Beam Selection and Interference Cancellation in Lens Millimeter Wave NOMA Systems

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China Communications 2022年第4期19卷 57-66页

作者： Lei Xu jing cai jing Chang Hongyu Fang Xiaohui Li School of Electronics and Information Engineering Anhui UniversityHefei 230601China

Non-orthogonal multiple access(NOMA)has been integrated in millimeter-wave(mmWave)Massive MImo systems to further enhance the spectrum efficiency, but NOMA has not been fully considered in lens mmWave systems. The fusion of these two technologies requires the joint design of beam selection and interference cancellation. In addition, when users follow the spatial cluster distribution, although the user clustering schemes based on K-means algorithm have been applied, the influence of the virtual and actual cluster center users on achievable sum rate has not been differentiated and analyzed in detail. To solve the above problems, a joint optimization scheme is proposed to maximize the achievable sum rate. The optimization problem is NP-hard, which is solved by using the divide-and-conquer approach. Concretely,based on the signal power loss analysis of directional deviation, a beam selection algorithm is designed for inter-cluster interference cancellation based on the Kmeans algorithm. Further for intra-cluster interference cancellation, a power allocation algorithm based on the bisection method is designed to guarantee the fairness of users in each cluster. The simulation results show that the proposed scheme offers a significant performance improvement in terms of both achievable sum rate and energy efficiency, and it is suitable for the large-scale user scenario due to its low complexity.

关键词： lens mmWave systems NOMA user clustering beam selection power allocation

Visible light-mediated C—P bond formation reactions

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Science Bulletin 2019年第5期64卷 337-350页

作者： Bao-Gui cai Jun Xuan Wen-jing Xiao Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials College of Chemistry & Chemical Engineering Anhui University Key Laboratory of Pesticide & Chemical Biology Ministry of Education College of Chemistry Central China Normal University

Organophosphorus compounds have attracted continuous attention in materials science, agrochemical and pharmaceutical fields due to their unique bioactivities. Thus, the development of novel and robust manners for the construction new C—P bond has therefore gained great interests in synthetic organic chemistry. Because of their intrinsic sustainability and green chemistry character, visible light-induced photoredox catalysis has been widely applied in the construction of new chemical bonds, including the formation of C—P bond. In this review, we summarized recent achievements in C—P bond formation reactions initiated by visible light-induced photoredox catalysis, which mainly focusing on the discussion of reaction design and the mechanism.

关键词： C-P bond formation Organophosphorus compounds Photoredox catalysis Visible light

Influence of lactic acid on the two-phase anaerobic digestion of kitchen wastes

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Journal of Environmental Sciences 2007年第2期19卷 244-249页

作者： ZHANG Bo cai Wei-min HE Pin-jing State Key Laboratory of PoUution Control and Resources Reuse Tongji University Shanghai 200092 China School of Environmental Science and Engineering Shanghai Jiaotong University Shanghai 200240 China

To evaluate the influence of lactic acid on the methanogenesis, anaerobic digestion of kitchen wastes was firstly conducted in a two-phase anaerobic digestion process, and performance of two digesters fed with lactic acid and glucose was subsequently compared. The results showed that the lactic acid was the main fermentation products of hydrolysis-acidification stage in the two-phase anaerobic digestion process for kitchen wastes. The lactic acid concentration constituted approximately 50% of the chemical oxygen demand （COD） concentration in the hydrolysis-acidification liquid. The maximum organic loading rate was lower in the digester fed with lactic acid than that fed with glucose. Volatile fatty acids （VFAs） and COD removal were deteriorated in the methanogenic reactor fed with lactic acid compared to that fed with glucose. The specific methanogenic activity （SMA） declined to 0.343 g COD/（gVSS-d） when the COD loading were designated as 18.8 g/（L-d） in the digester fed with lactic acid. The propionic acid accumulation occurred due to the high concentration of lactic acid fed. It could be concluded that avoiding the presence of the lactic acid is necessary in the hydrolysis-acidification process for the improvement of the two-phase anaerobic digestion process of kitchen wastes.

关键词： lactic acid kitchen wastes anaerobic digestion methanogenesis

PAHs in aquatic sediment in Hangzhou, China: Analytical methods, pollution pattern, risk assessment and sources

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Journal of Environmental Sciences 2005年第5期17卷 748-755页

作者： ZHU Li-zhong cai Xue-fen WANG jing Department of Environmental Science Zhejiang University Hangzhou 310028 China Women＇s Hospital School of Medicine Zhejiang University Hangzhou 310006 China Zhejiang Provincial Environmental monitoring Centre Hangzhou 310012 China

Eleven surface sediment samples, from Hangzhou section of Qiantang River and jinghang Canal, west Lake the inland river were collected to investigate 17 polycycUc aromatic hydrocarbons（PAHs） pollution in aquatic sediments of Hangzhou. Accelerated solvent extraction（ASE） was used to extract PAHs from sediments with satisfactory recoveries. It was found that the total PAHs in the sediments ranged from 308.4 to 3037 ng/g dw, and PAHs pollution in sediments from jinghang Canal were the heaviest. Lowest effect level（LEL） and severe effect level （SEL） sediment quality guidelines were introduced to perform risk assessment for PAHs pollution in aquatic sediments. Only one sample in jinghang Canal had adverse impact on benthic organism. 2-3 ring PAHs had a noticeable contribution to total PAHs, especially NA, PHEN. A quantity method was used to determine the major source, the results showed petroleum origin was the chief source to PAHs pollution in all sediments with the exception of sediments from jinghang Canal where combustion sources had a larger contribution.

关键词： PAHs ASE sediment source risk assessment

Fast Community Detection Based on Distance Dynamics

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Tsinghua Science and Technology 2017年第6期22卷 564-585页

作者： Lei Chen jing Zhang Lijun cai Ziyun Deng School of Information and Electrical Engineering Hunan University of Science and Technology Xiangtan 411201 China jing Zhang is with the College of Electrical and Information Engineering Hunan University Changsha 410082 China Lijun cai is with the College of Information Science and Engineering Hunan University Changsha 410082 China. Ziyun Deng is with the Department of Economics and Trade Changsha Commerce and Tourism College Changsha 410082 China

The distance dynamics model is excellent tool for uncovering the community structure of a complex network. However, one issue that must be addressed by this model is its very long computation time in large-scale networks. To identify the community structure of a large-scale network with high speed and high quality, in this paper, we propose a fast community detection algorithm, the F-Attractor, which is based on the distance dynamics model. The main contributions of the F-Attractor are as follows. First, we propose the use of two prejudgment rules from two different perspectives： node and edge. Based on these two rules, we develop a strategy of internal edge prejudgment for predicting the internal edges of the network. Internal edge prejudgment can reduce the number of edges and their neighbors that participate in the distance dynamics model. Second, we introduce a triangle distance to further enhance the speed of the interaction process in the distance dynamics model. This triangle distance uses two known distances to measure a third distance without any extra computation. We combine the above techniques to improve the distance dynamics model and then describe the community detection process of the F-Attractor. The results of an extensive series of experiments demonstrate that the F-Attractor offers high-speed community detection and high partition quality.

关键词： community detection interaction model complex network graph clustering graph mining

Impact of Different AC Voltage Control modes of Wind-farm-side MMC on Stability of MMC-HVDC with Offshore Wind Farms

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Journal of modern Power Systems and Clean Energy 2023年第5期11卷 1687-1699页

作者： Hongfei Lin Tao Xue jing Lyu Xu cai Key Laboratory of Control of Power Transmission and Conversion Ministry of EducationDepartment of Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghaiChina Department of Electrical Engineering The Hong Kong Polytechnic UniversityHong KongChina

Wind-farm-side modular multilevel converters(WFMMCs) used in modular multilevel converter based highvoltage direct current(MMC-HVDC) transmission systems must be able to control the AC grid voltage in offshore wind farms. Different AC voltage control strategies can significantly affect the dynamic characteristics of WFMMCs. However, existing studies have not provided a general methodology of controller parameter design, and few comparative studies have been conducted on control performance under varying operating conditions as well as the effects of different AC voltage control modes(AVCMs) on the stability of MMC-HVDCs with offshore wind farms. This paper provides a controller parameter design method for AVCMs, which is tested in various operating scenarios. Sequence impedance models of offshore wind farms and WFMMCs under different AVCMs are then developed. The effects of AVCMs on the small-signal stability of the interconnected system are then analyzed and compared using the impedance-based method. Finally, case studies are conducted on a practical MMC-HVDC system with offshore wind farms to verify the theoretical analysis.

关键词： Offshore wind farm modular multilevel converter based high-voltage direct current(MMC-HVDC) AC voltage control stability dynamic response

Opioid system in L-DOPA-induced dyskinesia

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Translational Neurodegeneration 2017年第1期6卷 1-5页

作者： jing Pan Huaibin cai Transgenics Section Laboratory of NeurogeneticsNational Institute on AgingNational Institutes of HealthBuilding 35Room 1A112MSC 370735 Convent DriveBethesdaMD 20892-3707USA

L-3,4-Dihydroxyphenylalanine(L-DOPA)-induced dyskinesia(LID)is a major clinical complication in the treatment of Parkinson’s disease(PD).This debilitating side effect likely reflects aberrant compensatory responses for a combination of dopaminergic neuron denervation and repeated L-DOPA *** endogenous opioid signal transduction pathways in basal ganglia have been well documented in *** receptors have been targeted to alleviate the ***,the exact role of this altered opioid activity is remains under active *** the present review,we discuss the current understanding of opioid signal transduction in the basal ganglia and how the malfunction of opioid signaling contributes to the pathophysiology of *** study of the opioid system in LID may lead to new therapeutic targets and improved treatment of PD patients.

关键词： opioid endogenous system

VA族元素修饰对二维AlN电磁性质调控的理论研究

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原子与分子物理学报 2025年第6期42卷 159-166页

作者：莫秋燕陈广萍张颂荆涛吴家隐凯里学院大数据工程学院凯里556011 凯里学院理学院凯里556011 广东开放大学(广东理工职业学院)工程技术学院广州510091

采用基于密度泛函理论的第一性原理计算方法,研究了VA族元素(N、P、As、Sb、Bi)对二维AlN电磁性质的影响.研究发现,VA族元素修饰后,二维AlN的能带结构发生显著劈裂,表明体系转变为磁性材料.同时,导带底部向低能量区域移动,使得二维AlN... 详细信息

采用基于密度泛函理论的第一性原理计算方法,研究了VA族元素(N、P、As、Sb、Bi)对二维AlN电磁性质的影响.研究发现,VA族元素修饰后,二维AlN的能带结构发生显著劈裂,表明体系转变为磁性材料.同时,导带底部向低能量区域移动,使得二维AlN的吸收阈值从紫外线区域扩展至可见光区域.因此,VA族元素的修饰显著调控了二维AlN的电子结构和磁性,为实现可见光响应的光电子和自旋电子器件提供了新思路和可能性.

关键词：二维AlN 第一性原理修饰电子结构

Near-infrared diffuse reflectance spectroscopy with sample spots and chemometrics for fast determination of bovine serum albumin in micro-volume samples

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Chinese Chemical Letters 2013年第1期24卷 67-69页

作者： cai-jing Cui Wen-Sheng cai Xue-Guang Shao Research Center for Analytical Sciences College of ChemistryNankai University

Near-infrared diffuse reflectance spectroscopy （NIRDRS） has attracted more and more attention in analyzing the components in samples with complex matrices. However, to apply this technique to micro-analysis, there are still some obstacles to overcome such as the low sensitivity and spectral overlapping associated with this approach. A method for fast determination of bovine serum albumin （BSA） in micro-volume samples was studied using NIRDRS with sample spots and chemometric techniques. 10 p^L of sample spotted on a filter paper substrate was used for the spectral measurements. Quantitative analysis was obtained by partial least squares （PLS） regression with signal processing and variable selection. The results show that the correlation coefficient （R） between the predicted and the reference concentration is 0.9897 and the recoveries are in the range of 87.4%-114.4% for the validation samples in the concentration range of 0.61-8.10 mg/mL. These results suggest that the method has the potential to quickly measure proteins in micro-volume solutions.

关键词： Near-infrared diffuse reflectancespectroscopySample spotFilter paperProteinMicro-volume analysis