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Science China(Information Sciences) 2019年第7期62卷 45-63页

作者： Feng jiang Jiaqi HE Zhigang ZENG School of Statistics and Mathematics Zhongnan University of Economics and Law School of Automation Huazhong University of Science and Technology

In this paper, a hybrid approach consisting of pigeon-inspired optimization(PIO) and extreme learning machine(ELM) based on wavelet packet analysis(WPA) is presented for predicting bulk commodity futures prices. Firstly, WPA is applied to decompose the original futures prices into a set of lower-frequency subseries. Secondly, the PIO algorithm is used to optimize the parameters of ELM and then the optimized ELM is utilized to forecast the subseries. Finally, we adopt the hybrid method to calculate the final forecasting outcomes of futures prices. In order to further test the predictive ability of the hybrid forecasting model on bulk commodity futures prices, we use the prices of West Texas Intermediate crude oil futures and Chicago Board of Trade soybean futures to make one-step, two-step and four-step ahead predictions. In comparison with complete ensemble empirical mode decomposition with adaptive noise, empirical mode decomposition and singular spectrum analysis, WPA is the most suitable for decomposing bulk commodity futures *** experimental outcomes show that the hybrid WPA-PIO-ELM model has better performance on horizontal precision, directional precision and robustness.

关键词： wavelet packet analysis extreme learning machine pigeon-inspired optimization bulk commodity futures price prediction directional precision

Distribution performance of gas–liquid mixture in the shell side of spiral-wound heat exchangers

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2284-2292页

作者： Wenke Zheng Weihua Cai Yiqiang jiang School of Architecture Harbin Institute of TechnologyHarbin 150090China Key Laboratory of Cold Region Urban and Rural Human Settlement Environment Science and Technology Ministry of Industry and Information TechnologyHarbin 150090China School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of Energy and Power Engineering Northeast Electric Power UniversityJilin 132012China

The non-uniformity of gas–liquid mixture is a critical issue which leads to the heat transfer deterioration of spiralwound heat exchangers(SWHEs).Two-phase mass flow rate and the content of gas are important parameters as well as structural parameters which have prominent influences on flow distribution uniformity of SWHE shell *** order to investigate the influences of these parameters,an experimental test system was built using water and air as mediums and a novel distributor named"tubes distributor"was *** effects of mass flow rate and the content of gas on two-phase distribution performance were analyzed,where the mass flow rate ranged from 28.4 to 171.9 kg·h-1 and the content of gas changed from 0.2 to 0.8,*** results showed that the mixture mass flow rate considerably influenced the liquid distribution than that of gas phase and the larger mass flow rate exhibited the better distribution uniformity of two-phase *** was also found that the tubes distributor had the better two-phase uniformity when the content of gas was around *** diameter played an important role in the distribution of gas phase and slit width was more significant for the uniformity of liquid phase.

关键词： Spiral-wound heat exchanger Gas–liquid mixture Multiphase flow Distribution uniformity

Spatial and historical distribution of organic phosphorus driven by environment conditions in lake sediments

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Journal of Environmental Sciences 2018年第2期30卷 32-41页

作者： Changwei Lü jiang He Bing Wang School of Ecology and Environment Inner Mongolia University Institute of Environmental Geology Inner Mongolia University Forestry College Inner Mongolia Agricultural University

The chemistry of sedimentary organic phosphorus（OP） and its fraction distribution in sediments are greatly influenced by environmental conditions such as terrestrial inputs and runoffs. The linkage of OP with environmental conditions was analyzed on the basis of OP spatial and historical distributions in lake sediments. The redundancy analysis and OP spatial distribution results suggested that both Na OH-OP（OP extracted by Na OH） and Re-OP（residual OP） in surface sediments from the selected 13 lakes reflected the gradient effects of environmental conditions and the autochthonous and/or allochthonous inputs driven by latitude zonality in China. The lake level and salinity of Lake Hulun and the runoff and precipitation of its drainage basin were reconstructed on the basis of the geochemistry index. This work showed that a gradient in weather conditions presented by the latitude zonality in China impacts the OP accumulation through multiple drivers and in many *** drivers are mainly precipitation and temperature, governing organic matter（OM）production, degradation rate and transportation in the watershed. Over a long temporal dimension（4000 years）, the vertical distributions of Re-OP and Na OH-OP based on a dated sediment profile from HLH were largely regulated by the autochthonous and/or allochthonous inputs, which depended on the environmental and climate conditions and anthropogenic activities in the drainage basin. This work provides useful environmental geochemistry information to understand the inherent linkage of OP fractionation with environmental conditions and lake evolution.

关键词： Organic phosphorus Spatial and historical distribution Environmental conditions Sediment Lake

Quantized anomalous Hall resistivity achieved in molecular beam epitaxy-grown Mn Bi2Te4 thin films

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National Science Review 2024年第2期11卷 24-32页

作者： Yunhe Bai Yuanzhao Li Jianli Luan Ruixuan Liu Wenyu Song Yang Chen Peng-Fei Ji Qinghua Zhang Fanqi Meng Bingbing Tong lin Li Yuying jiang Zongwei Gao lin Gu Jinsong Zhang Yayu Wang Qi-Kun Xue Ke He Yang Feng Xiao Feng State Key Laboratory of Low Dimensional Quantum Physics Department of Physics Tsinghua University Institute of Physics Chinese Academy of Sciences School of Materials Science and Engineering Tsinghua University Beijing Academy of Quantum Information Sciences Frontier Science Center for Quantum Information Hefei National Laboratory Southern University of Science and Technology

The intrinsic magnetic topological insulator MnBi2Te4provides a feasible pathway to the high-temperature quantum anomalous Hall（QAH） effect as well as various novel topological quantum phases. Although quantized transport properties have been observed in exfoliated MnBi2Te4thin flakes, it remains a big challenge to achieve molecular beam epitaxy（MBE）-grown MnBi2Te4thin films even close to the quantized regime. In this work, we report the realization of quantized anomalous Hall resistivity in MBE-grown MnBi2Te4thin films with the chemical potential tuned by both controlled in situ oxygen exposure and top gating. We find that elongated post-annealing obviously elevates the temperature to achieve quantization of the Hall resistivity, but also increases the residual longitudinal resistivity, indicating a picture of high-quality QAH puddles weakly coupled by tunnel barriers. These results help to clarify the puzzles in previous experimental studies on MnBi2Te4and to find a way out of the big difficulty in obtaining MnBi2Te4samples showing quantized transport properties.

关键词： intrinsic magnetic topological insulator quantized anomalous Hall resistivity molecular beam epitaxy quantized transport property

Influences of Ignition Temperature, Urea-to-Metal Nitrates Molar Ratio, and Further Calcination on Synthesis of C_4AF via the SPCR Method

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Journal of Wuhan University of Technology(Materials Science) 2018年第5期33卷 1168-1175页

作者： LI Yang HE Zhen jiang Rui State Key Laboratory of Water Resources ＆ Hydropower Engineering Science Wuhan UniversityWuhan 430072China Shaanxi Key Laboratory of Safety and Durability of Concrete Structures Xo＇ing UniversityXi＇an 710123China

The self-propagating combustion reaction（SPCR）method was employed to synthesize C4AF using metal nitrates as cation precursors and urea as *** decomposition behavior of dried gels,phase identification and crystallinity of synthesized C4AF,and impact of urea to metal nitrates（UR/MN）molar ratio on synthesis effect were investigated with the aid of differential thermogravimetric analysis,X-ray diffraction and Fourier transform inferred *** is found that pure C4AF can be prepared by the SPCR method in 2 h at 500℃.The UR/MN molar ratio plays a significant role in the thermal decomposition behavior of dried gel,purity,crystallinity and crystallite size of synthesized *** temperature should be not lower than 500℃but higher temperatures were *** trace of free lime in synthesized C4AF is detected and calcium carbonate is the transition *** calcining the synthesized C4AF at high temperatures is beneficial for increasing crystallinity,purity and crystallite *** activation energy of the further calcination process is 119.6 kJ/*** is more efficient to improve the synthesis effect by increasing UR/MN molar ratio than further calcination at high temperatures.

关键词： C4AF combustion synthesis self-propagating brownmillerite purity low temperature

论《统计法》罚款对象的设定与完善——对第二十七条罚则的思索

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统计研究 2005年第7期22卷 8-11页

作者：蒋晖湖南省怀化市洪江区统计局

The paper expresses the opinions and improving suggestions of a statistician of grass roots about Article 27 of the Statistics Law.

关键词：《统计法》罚款对象第二十七条罚则中国统计人员统计资料构成条件

Adsorption and desorption of Cu(Ⅱ) and Pb(Ⅱ) in paddy soils cultivated for various years in the subtropical China

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Journal of Environmental Sciences 2010年第5期22卷 689-695页

作者： Liang Ma Renkou Xu Jun jiang State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China Graduate University of Chinese Academy of Sciences Beifing 100049 China

The adsorption and desorption of Cu（Ⅱ） and Pb（Ⅱ） on upland red soil,and paddy soils which were originated from the upland soil and cultivated for 8,15,35 and 85 years,were investigated using the batch *** study showed that the organic matter content and cation exchange capacity （CEC） of the soils are important factors controlling the adsorption and desorption of Cu（Ⅱ） and Pb（Ⅱ）.The 15-Year paddy soil had the highest adsorption capacity for Pb（Ⅱ）,followed by the 35-Year paddy *** the 35-Year paddy soil and 15-Year paddy soil adsorbed more Cu（Ⅱ） than the upland soil and other paddy *** 15-Year paddy soils exhibited the highest desorption percentage for both Cu（Ⅱ） and Pb（Ⅱ）.These results are consistent with the trend for the CEC of the soils *** high soil CEC contributes not only to the adsorption of Cu（Ⅱ） and Pb（Ⅱ） but also to the electrostatic adsorption of the two heavy metals by the *** desorption percentages for Cu（Ⅱ）（36.7% to 42.2%） and Pb（Ⅱ）（50.4% to 57.9%） were observed for the 85-Year paddy *** highest content of organic matter in the soil was responsible for the low desorption percentages for the two metals because the formation of the complexes between the organic matter and the metals could increase the stability of the heavy metals in the soils.

关键词： adsorption and desorption Cu(Ⅱ) Pb(Ⅱ) cultivation chronosequence paddy soil

Space-borne antenna adaptive anti-jamming method based on gradient-genetic algorithm

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Journal of Systems Engineering and Electronics 2007年第3期18卷 469-475页

作者： Tao Haihong Liao Guisheng Yu jiang National Key Lab. of Radar Signal Processing Xidian Univ. Xi'an 710071 P. R. China

A novel space-borne antenna adaptive anti-jamming method based on the genetic algorithm （GA）, which is combined with gradient-like reproduction operators is presented, to search for the best weight for pattern synthesis in radio frequency （RF）. Combined, the GA＇s the capability of the whole searching is, but not limited by selection of the initial parameter, with the gradient algorithm＇s advantage of fast searching. The proposed method requires a smaller sized initial population and lower computational complexity. Therefore, it is flexible to implement this method in the real-time systems. By using the proposed algorithm, the designer can efficiently control both main-lobe shaping and side-lobe level. Simulation results based on the spot survey data show that the algorithm proposed is efficient and feasible.

关键词： space-borne antenna genetic algorithm (GA) gradient-like anti-jamming pattern synthesis.

Optimization of projectile state and trajectory of reentry body considering attainment of carrying aircraft

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Journal of Systems Engineering and Electronics 2017年第1期28卷 137-144页

作者： Changsheng Gao Chunwang jiang Wuxing Jing School of Astronautics Harbin Institute of TechnologyHarbin 150001China

As an improvement of traditional maximum range trajectory optimization, both the projectile state and control sequence of reentry body are optimized to achieve the maximum range. To ensure the optimal projectile state is in the reachable domain of the carrying aircraft, the climb of the carrying aircraft and the flight of reentry body are optimized as a whole based on the hp-adaptive pseudospectral method. Meanwhile, the path constraints, control constraints and initial/terminal states constraints are considered in the optimization as well. In face of the fact that the range of the optimal control solution resulted from the pseudospectral method may be unsmooth, virtual control variables (second derivatives of the angle of attack and bank angle) are proposed in the optimization, while the angle of attack and bank angle are treated as the virtual state variables to guarantee the smoothness of the optimal control solution. The validity of the virtual control variables in smoothing the optimal control solution is verified by simulation, and the optimality of the resulting projectile state and control sequence for reaching the maximum range is confirmed using the indirect approach. © 1990-2011 Beijing Institute of Aerospace Information.

关键词： Aerodynamics Angle of attack Optimal control systems Projectiles

Establishment and assessment of rodent models of medication-related osteonecrosis of the jaw(MRONJ)

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International Journal of Oral Science 2022年第3期14卷 245-258页

作者： Ran Yan Ruixue jiang Longwei Hu Yuwei Deng Jin Wen Xinquan jiang Department of Prosthodontics Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai Jiao Tong UniversityShanghaiChina College of Stomatology Shanghai Jiao Tong UniversityShanghaiChina National Center for Stomatology National Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghai Engineering Research Center of Advanced Dental Technology and MaterialsShanghaiChina d 4Department of Oral and Maxillofacial-Head and Neck Oncology Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai Jiao Tong UniversityShanghaiChina

Medication-related osteonecrosis of the jaw(MRONJ)is primarily associated with administering antiresorptive or antiangiogenic *** significant research on MRONJ,its pathogenesis and effective treatments are still not fully *** models can be used to simulate the pathophysiological features of MRONJ,serving as standardized in vivo experimental platforms to explore the pathogenesis and therapies of *** models exhibit excellent effectiveness and high reproducibility in mimicking human MRONJ,but classical methods cannot achieve a complete replica of the pathogenesis of *** rodent models have been reported with improvements for better mimicking of MRONJ onset in *** review summarizes representative classical and modified rodent models of MRONJ created through various combinations of systemic drug induction and local stimulation and discusses their effectiveness and ***,there is a lack of a unified assessment system for MRONJ models,which hinders a standard definition of MRONJ-like lesions in ***,this review comprehensively summarizes assessment systems based on published peer-review articles,including new approaches in gross observation,histological assessments,radiographic assessments,and serological *** review can serve as a reference for model establishment and evaluation in future preclinical studies on MRONJ.

关键词： Establishment and assessment of rodent models of medication-related osteonecrosis of the jaw MRONJ