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Spectral and energy efficiency analysis for massive MIMO multi-pair two-way relaying networks under generalized power scaling

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Science China(Information Sciences) 2017年第10期60卷 155-168页

作者： Jing YANG Hongyan WANG Jie ding Xiqi GAO Zhiguo ding National Mobile Communications Research Laboratory Southeast University School of Information Engineering Yangzhou University Department of Communication Systems Lancaster University

In this work, we investigate the spectral efficiency(SE) and energy efficiency(EE) for a massive multiple-input multiple-output multi-pair two-way amplify-and-forward relaying system, where multi-pair users exchange information via a relay station equipped with large scale antennas. We assume that imperfect channel state information is available and maximum-ratio combining/maximum-ratio transmission beamforming is adopted at the relay station. Considering constant or scaled transmit power of pilot sequences, we quantify the asymptotic SE and EE under general power scaling schemes, in which the transmit power at each user and relay station can both be scaled down, as the number of relay antennas tends to infinity. In addition, a closed-form expression of the SE has been obtained approximately. Our results show that by using massive relay antennas, the transmit power at each user and the relay station can be scaled down, with a non-vanishing signal to interference and noise ratio(SINR). Finally, simulation results confirm the validity of our analysis.

关键词： massive MIMO two-way relaying power scaling imperfect CSI energy efficiency spectral efficiency

Low Temperature Thermal History Reconstruction Based on Apatite Fission-Track Length Distribution and Apatite U-Th/He Age Using Low-T Thermo

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Journal of Earth Science 2023年第3期34卷 717-725页

作者： Ruxin ding Guangdong Provincial Key Lab of Geodynamics and Geohazards School of Earth Sciences and EngineeringSun Yat-Sen UniversityZhuhai 519000China Guangdong Provincial Key Lab of Mineral Resources and Geological Processes and Mineral Resources Zhuhai 519000China Low-T Lab Shanghai 201101China

Low temperature thermochronology plays a key role in the study of the tectonic evolution of the upper *** modeling of apatite fission-track requires the apparent age and the confined track-length distribution of spontaneous *** length data does not require either thermal neutron irradiation or LA-ICP-MS measurements of the uranium content of the *** paper attempts to decouple the apatite fission-track age from the apatite fission-track length,but to combine the fission-track lengths with the respective apatite U-Th/He age to model the thermal *** experiments were designed and conducted using a new Mathematica®modeling software“Low-T Thermo”.Results of this modeling show that the thermal history modeling of apatite U-Th/He and fission-track ages can constrain the apatite fission-track length thermal history in the He partial retention zone and fission-track partial annealing zone,*** implies that this combination of apatite fissiontrack length and apatite U-Th/He age has not been implemented before but is presented here as an alternative way of determining thermal histories without the addition of apatite fission-track age.

关键词： thermal history modeling apatite fission track U-Th/He tectonics

New insights on driving factors of East Asian droughts and floods

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Science China Earth Sciences 2024年第12期67卷 3957-3959页

作者： Yihui ding National Climate Center China Meteorological AdministrationBeijing 100081China

*** As one of the most densely populated regions in the world,East Asia suffers significant socioeconomic impacts from extreme events such as heatwaves,floods,and tropical *** instance,in July 2021,Henan province was struck by a record-breaking rainstorm,with Zhengzhou experiencing unusual precipitation intensities reaching 201.9 mm per hour.

关键词： floods driving breaking

The roles of R2R3-MYBs in regulating complex pigmentation patterns in flowers

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Horticultural Plant Journal 2023年第6期9卷 1067-1078页

作者： Baoqing ding State Key Laboratory of Crop Genetics&Germplasm Enhancement and Utilization Key Laboratory of LandscapingMinistry of Agriculture and Rural AffairsKey Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East ChinaCollege of HorticultureNanjing Agricultural UniversityNanjingJiangsu 210095China Zhongshan Biological Breeding Laboratory NanjingJiangsu 210014China

Pigmentation patterns are ubiquitous in *** striking pigmentation patterns are not only aesthetically appealing,but also crucial to pollinator interaction and plant *** formation of complex floral pigmentation patterns mainly relies on the spatiotemporal expression of R2R3-MYB transcription factors and is often associated with certain floral development programs,such as floral organ identity,symmetry,which likely provide key information to initiate the *** a complex pigmentation pattern to form,at least a pair of activator and inhibitor is required,despite their interaction might vary depending on the system being *** regulation of pigmentation pattern involves multiple molecular mechanisms,such as transcriptional regulation,small RNA,transposon-mediated gene silencing,and methylation of gene *** these regulators can be facilitated by using single-cell and spatial transcriptomics as well as innovative plant transformation ***,plant organ development and pigmentation patterns are often interdependent,but current methods of describing patterns are ***,more precise and quantitative measurements are needed to elucidate the developmental mechanisms underlying complex pigmentation patterns in flowers.

关键词： Pattern formation Reaction-diffusion Petals Prepattern R2R3-MYB Anthocyanin Carotenoid Stripes Spots

THEORETICAL AND EXPERIMENTAL STUDIES ON FRACTURE PLANE CONTROL BLAST WITH NOTCHED BOREHOLES

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中国有色金属学会会刊：英文版 1999年第1期9卷 190-193页

作者： Dexin, ding Central South Inst of Technology Hengyang China

１ＩＮＴＲＯＤＵＣＴＩＯＮＤｕｒｉｎｇｒｅｃｅｎｔｙｅａｒｓ，ｑｕｉｔｅａｆｅｗｉｎｖｅｓｔｉｇａｔｏｒｓｈａｖｅｗｏｒｋｅｄｏｎｆｒａｃｔｕｒｅｐｌａｎｅｃｏｎｔｒｏｌｂｌａｓｔｗｉｔｈｎｏｔｃｈｅｄｂｏｒｅｈｏ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＤｕｒｉｎｇｒｅｃｅｎｔｙｅａｒｓ，ｑｕｉｔｅａｆｅｗｉｎｖｅｓｔｉｇａｔｏｒｓｈａｖｅｗｏｒｋｅｄｏｎｆｒａｃｔｕｒｅｐｌａｎｅｃｏｎｔｒｏｌｂｌａｓｔｗｉｔｈｎｏｔｃｈｅｄｂｏｒｅｈｏｌｅｓ．Ｓｕｃｃｅｓｆｕｌａｐｐｌ...

关键词： fracture plane control blast notched borehole fracture mechanics

Response Sensitivity Analysis of the Dynamic Milling Process Based on the Numerical Integration Method

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Chinese Journal of Mechanical Engineering 2012年第5期25卷 940-946页

作者： ding Ye ZHU Limin ZHANG Xiaojian ding Han State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240 China State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology Wuhan 430074 China

As one of the bases of gradient-based optimization algorithms, sensitivity analysis is usually required to calculate the derivatives of the system response with respect to the machining parameters. The most widely used approaches for sensitivity analysis are based on time-consuming numerical methods, such as finite difference methods. This paper presents a semi-analytical method for calculation of the sensitivity of the stability boundary in milling. After transforming the delay-differential equation with time-periodic coefficients governing the dynamic milling process into the integral form, the Floquet transition matrix is constructed by using the numerical integration method. Then, the analytical expressions of derivatives of the Floquet transition matrix with respect to the machining parameters are obtained. Thereafter, the classical analytical expression of the sensitivity of matrix eigenvalues is employed to calculate the sensitivity of the stability lobe diagram. The two-degree-of-freedom milling example illustrates the accuracy and efficiency of the proposed method. Compared with the existing methods, the unique merit of the proposed method is that it can be used for analytically computing the sensitivity of the stability boundary in milling, without employing any finite difference methods. Therefore, the high accuracy and high efficiency are both achieved. The proposed method can serve as an effective tool for machining parameter optimization and uncertainty analysis in high-speed milling.

关键词： milling stability sensitivity of the stability boundary numerical integration method

Hierarchical Optimization of Landing Performance for Lander with Adaptive Landing Gear

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Chinese Journal of Mechanical Engineering 2019年第2期32卷 24-35页

作者： Zongmao ding Hongyu Wu Chunjie Wang Jianzhong ding School of Mechanical Engineering and Automation Beijing University of Aeronautics and Astronautics Beijing System Design Institute of Electro-Mechanic Engineering China Aerospace Science and Industry Corporation Limited Department of Mechanical Engineering Tsinghua University State Key Laboratory of Virtual Reality and Systems Beijing University of Aeronautics and Astronautics

A parameterized dynamics analysis model of legged lander with adaptive landing gear was established. Based on the analysis model, the landing performances under various landing conditions were analyzed by the optimized Latin hypercube experimental design method. In order to improve the landing performances, a hierarchical optimization method was proposed considering the uncertainty of landing conditions. The optimization problem was divided into a higher level(hereafter the "leader") and several lower levels(hereafter the "follower"). The followers took condition?ing factors as design variables to find out the worst landing conditions, while the leader took bu er parameters as design variables to better the landing performance under worst conditions. First of all, sensitivity analysis of landing conditioning factors was carried out according to the results of experimental design. After the sensitive factors were screened out, the response surface models were established to reflect the complicated relationships between sensi?tive conditioning factors, bu er parameters and landing performance indexes. Finally, the response surface model was used for hierarchical optimization iteration to improve the computational e ciency. After selecting the optimum bu er parameters from the solution set, the dynamic model with the optimum parameters was simulated again under the same landing conditions as the simulation before. After optimization, nozzle performance against damage is improved by 5.24%, the acceleration overload is reduced by 5.74%, and the primary strut improves its performance by 21.10%.

关键词： Landing gear Soft landing Sensitivity analysis Response surfaces Hierarchical optimization

MC-ICP-MS 测定岩石标准物质的钒同位素组成

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岩矿测试 2025年第1期44卷 63-74页

作者：徐丽怡于慧敏丁昕黄方中国科学技术大学地球和空间科学学院岩石圈演化与环境演变全国重点实验室安徽合肥230026 中国科学院比较行星学卓越创新中心中国科学技术大学安徽合肥230026

随着分析方法的发展和分析精度的提升,钒同位素已经越来越多地被用于各种地质过程研究。为了确保钒同位素分析测试过程中,可以有效地监控数据的准确度和精度,方便国际各实验室之间的数据对比,同时考虑到早期国际上常用美国地质调查局(US... 详细信息

随着分析方法的发展和分析精度的提升,钒同位素已经越来越多地被用于各种地质过程研究。为了确保钒同位素分析测试过程中,可以有效地监控数据的准确度和精度,方便国际各实验室之间的数据对比,同时考虑到早期国际上常用美国地质调查局(USGS)的标准物质面临着库存不足等问题,本文采用多接收电感耦合等离子体质谱仪(MC-ICP-MS)测定了一系列国际地质标准物质和国家地质标准物质的钒同位素组成,δ51V值的测试精度优于0.08‰。本文选取的标准物质主要来自日本地质调查局(GSJ)和中国地质科学院地球物理地球化学勘查研究所(IGGE),包括一个安山岩(JA-1),三个玄武岩(JB-3、JB-1b和GBW07105),一个辉长岩(JGb-1),一个辉绿岩(GBW07123)以及一个土壤(GBW07454),钒含量范围为77~635μg/g,涵盖了目前大部分火成岩和部分土壤等天然样品含量的范围。这些标准物质除了土壤GBW07454,其他标准物质的钒同位素组成未曾被报道。经测量表明,辉长岩标准物质JGb-1具有最高δ51V值,为−1.05‰±0.08‰,安山岩标准物质JA-1具有最低δ51V值,为−0.34‰±0.06‰,其余标准物质的δ51V值变化范围为−0.72‰~−0.81‰,均落在MORB范围内。本文对这些标准物质钒同位素组成的报道,丰富了钒同位素研究的标准物质数据库,有助于未来在更多领域开展钒同位素研究。

关键词：钒同位素火成岩 MC-ICP-MS 标准物质高精度分析方法

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Effects of effluent organic matters on endocrine disrupting chemical removal by ultrafiltration and ozonation in synthetic secondary effluent

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Journal of Environmental Sciences 2019年第2期31卷 57-64页

作者： Xiurong Si Zunfang Hu ding ding Xu Fu Civil Engineering Department North China Institute of Aerospace Engineering Shandong Institute of Geophysical and Geochemical Exploration

Endocrine disrupting chemicals(EDCs) in the secondary effluent discharged from wastewater treatment plants are of great concern when water reuse is intended. Ozonation and ultrafiltration(UF) are powerful technologies reported to eliminate EDCs. Due to the importance of effluent organic matters(EfOMs) in secondary effluent, the effects of three kinds of EfOM on the treatment of five EDCs using ozonation and UF were investigated. The three kinds of EfOM studied were humic acid sodium salt(NaAH), bovine serum albumin(BSA)and sodium alginate(NaAg); and the five EDCs were estrone, 17β-estradiol, estriol, 17α-ethynyl estradiol and bisphenol A. The results showed that EfOM accelerated the decay rate of ozone and inhibited the degradation efficiency of EDCs by ozonation in the order NaAH > BSA > *** ultraviolet absorbance at 280 nm(UVA_(280)) has potential for use as a surrogate indicator to assess EDC removal via ozonation without conducting difficult EDC analyses. When the decline in UVA_(280) exceeded 18%, the five EDCs had been completely removed. The UF behavior of NaAH,BSA and NaAg was found to follow the cake filtration law. The fouling potential of EfOM followed the order NaAg > NaAH > BSA; while EfOM on the membrane surface enhanced EDC removal in the order NaAH > BSA > NaAg. The mean retention rate of the membrane was increased by 24%, 10% and 8%, respectively. The properties of EDCs and EfOM cakes both influenced the EDC removal rates due to adsorption, size exclusion and charge attraction.

关键词： Endocrine disrupting chemicals Ultrafiltration Ozonation Effluent organic matters Secondary effluent