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Defence Technology（防务技术） 2024年第4期34卷 328-338页

作者： yangtian Liu Xiaopeng yan Qiang Liu tai An Jian Dai Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China china Research and Development Academy of Machinery Equipment Beijing 100089China

The identification of intercepted radio fuze modulation types is a prerequisite for decision-making in interference ***,the electromagnetic environment of modern battlefields is complex,and the signal-to-noise ratio(SNR)of such environments is usually low,which makes it difficult to implement accurate recognition of radio *** solve the above problem,a radio fuze automatic modulation recognition(AMR)method for low-SNR environments is ***,an adaptive denoising algorithm based on data rearrangement and the two-dimensional(2D)fast Fourier transform(FFT)(DR2D)is used to reduce the noise of the intercepted radio fuze intermediate frequency(IF)***,the textural features of the denoised IF signal rearranged data matrix are extracted from the statistical indicator vectors of gray-level cooccurrence matrices(GLCMs),and support vector machines(SVMs)are used for *** DR2D-based adaptive denoising algorithm achieves an average correlation coefficient of more than 0.76 for ten fuze types under SNRs of-10 d B and above,which is higher than that of other typical *** trained SVM classification model achieves an average recognition accuracy of more than 96%on seven modulation types and recognition accuracies of more than 94%on each modulation type under SNRs of-12 d B and above,which represents a good AMR performance of radio fuzes under low SNRs.

关键词： Automatic modulation recognition Adaptive denoising Data rearrangement and the 2D FFT(DR2D) Radio fuze

Underdetermined direction of arrival estimation with nonuniform linear motion sampling based on a small unmanned aerial vehicle platform

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Defence Technology（防务技术） 2024年第3期33卷 352-363页

作者： Xinwei Wang Xiaopeng yan tai An Qile Chen Dingkun Huang Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China

Uniform linear array(ULA)radars are widely used in the collision-avoidance radar systems of small unmanned aerial vehicles(UAVs).In practice,a ULA's multi-target direction of arrival(DOA)estimation performance suffers from significant performance degradation owing to the limited number of physical *** improve the underdetermined DOA estimation performance of a ULA radar mounted on a small UAV platform,we propose a nonuniform linear motion sampling underdetermined DOA estimation *** the motion of the UAV platform,the echo signal is sampled at different ***,according to the concept of difference co-array,a virtual ULA with multiple array elements and a large aperture is synthesized to increase the degrees of freedom(DOFs).Through position analysis of the original and motion arrays,we propose a nonuniform linear motion sampling method based on ULA for determining the optimal *** the condition of no increase in the aperture of the physical array,the proposed method obtains a high DOF with fewer sampling runs and greatly improves the underdetermined DOA estimation performance of *** results of numerical simulations conducted herein verify the superior performance of the proposed method.

关键词： Unmanned aerial vehicle(UAV) Uniform linear array(ULA) Direction of arrival(DOA) Difference co-array Nonuniform linear motion sampling method

De-biased knowledge distillation framework based on knowledge infusion and label de-biasing techniques

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Journal of Electronic Science and Technology 2024年第3期22卷 57-68页

作者： yan Li tai-Kang Tian Meng-Yu Zhuang Yu-Ting Sun School of Economics and Management University of Electronic Science and Technology of ChinaChengdu611731China School of Economics and Management Beijing University of Posts and TelecommunicationBeijing100876China School of Electrical Engineering and Computer Science The University of QueenslandBrisbane4072Australia

Knowledge distillation,as a pivotal technique in the field of model compression,has been widely applied across various ***,the problem of student model performance being limited due to inherent biases in the teacher model during the distillation process still *** address the inherent biases in knowledge distillation,we propose a de-biased knowledge distillation framework tailored for binary classification *** the pre-trained teacher model,biases in the soft labels are mitigated through knowledge infusion and label de-biasing *** on this,a de-biased distillation loss is introduced,allowing the de-biased labels to replace the soft labels as the fitting target for the student *** approach enables the student model to learn from the corrected model information,achieving high-performance deployment on lightweight student *** conducted on multiple real-world datasets demonstrate that deep learning models compressed under the de-biased knowledge distillation framework significantly outperform traditional response-based and feature-based knowledge distillation models across various evaluation metrics,highlighting the effectiveness and superiority of the de-biased knowledge distillation framework in model compression.

关键词： De-biasing Deep learning Knowledge distillation Model compression

植物雌激素协同化疗药的抗白血病作用体外研究

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中国实验血液学杂志 2008年第2期16卷 276-281页

作者：沈晶张伟京 yan-chin tai ching-Ho Stephen Wong Zhigang Xie Chien-Shing Chen 军事医学科学院附属医院肿瘤二科北京100071 新加坡国立大学医学院医学系新加坡119074 新加坡国大医院血液肿瘤科新加坡119074

异黄酮类的Genistein及daidzein和黄酮类的quercetin是天然的植物雌激素,具有抗癌特征。本研究探讨植物雌激素在急性和慢性粒细胞性白血病中的抗增殖作用及与化疗药的协同作用。用台盼蓝染色法分析genistein单独应用和与化疗药联合应用... 详细信息

异黄酮类的Genistein及daidzein和黄酮类的quercetin是天然的植物雌激素,具有抗癌特征。本研究探讨植物雌激素在急性和慢性粒细胞性白血病中的抗增殖作用及与化疗药的协同作用。用台盼蓝染色法分析genistein单独应用和与化疗药联合应用在NB4和HL-60白血病细胞中的抗增殖作用;用MTT法分析quercetin对K562及K562/A细胞的生长抑制作用;确定genistein与化疗药联合应用中同时及顺序给药的最佳作用次序;观察联合作用24、48、72小时后细胞的生长状态,研究genistein的凋亡诱导作用和细胞周期阻滞作用。结果表明:Genistein对NB4和HL-60白血病细胞有剂量、时间依赖性的增殖抑制作用,可诱导细胞凋亡和细胞周期阻滞。Genistein和化疗药联合应用对细胞生长有协同抑制作用,且与作用次序相关。Quercetin对白血病敏感株和耐药株均有明显的抑制作用。结论:本研究报道genistein和化疗药联合有协同抗白血病细胞增殖作用,具有作用次序相关性特性,这种联合应用有可能为白血病临床治疗提供新的思路。

关键词：金雀异黄素槲皮素植物雌激素 HL-60细胞 NB4细胞

Construction of coal pitch-based HA-K grafted poly condensates and their excellent anti-temperature and viscosity-reducing properties

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Petroleum Science 2024年第4期21卷 2806-2816页

作者： Jing Tan Wei Zhang Xiu-Ling yan Hao Zhou Sher Bahadar Khan Seitkhan Azat Shi-You yan Hao-Jie Ma Xin-tai Su Xinjiang Key Laboratory of Clean Conversion and High Value Utilization of Biomass Resources College of Chemistry and Chemical Engineering Yili Normal University School of Environment and Energy Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling South China University of Technology Drilling Fluid Branch of CNPC Xibu Drilling Engineering Company Limited Department of Chemistry Faculty of Science King Abdulaziz University PO Box 80203 Faculty of Chemistry and Chemical Technology Al-Farabi Kazakh National University Urumchi Huatailong Chemical Additives Co. Ltd.

Humic acids(HAs) are widely used as filtrate and viscosity reducers in drilling fluids. However, their practical utility is limited due to poor stability in salt resistance and high-temperature resistance. Hightemperature coal pitch(CP) is a by-product from coal pyrolysis above 650.C. The substance's molecular structure is characterized by a dense arrangement of aromatic hydrocarbon and alkyl substituents. This unique structure gives it unique chemical properties and excellent drilling performance, surpassing traditional humic acids in drilling operations. Potassium humate is prepared from CP(CP-HA-K) by thermal catalysis. A new type of high-quality humic acid temperature-resistant viscosity-reducer(Graft CP-HA-K polymer) is synthesized with CP-HA-K, hydrolyzed polyacrylonitrile sodium salt(Na-HPAN),urea, formaldehyde, phenol and acrylamide(AAM) as raw materials. The experimental results demonstrate that the most favorable conditions for the catalytic preparation of CP-HA-K are 1 wt% catalyst dosage, 30 wt% KOH dosage, a reaction temperature of 250.C, and a reaction time of 2 h, resulting in a maximum yield of CP-HA-K of 39.58%. The temperature resistance of the Graft CP-HA-K polymer is measured to be 177.39.C, which is 55.39.C higher than that of commercial HA-K. This is due to the abundant presence of amide, hydroxyl, and amine functional groups in the Graft CP-HA-K polymer,which increase the length of the carbon chains, enhance the electrostatic repulsion on the surface of solid particles. After being aged to 120.C for a specified duration, the Graft CP-HA-K polymer demonstrates significantly higher viscosity reduction(42.12%) compared to commercial HA-K(C-HA-K). Furthermore,the Graft CP-HA-K polymer can tolerate a high salt concentration of 8000 mg.L-1, measured after the addition of optimum amount of 3 wt% Graft CP-HA-K polymer. The action mechanism of Graft CP-HA-K polymer on high-temperature drilling fluid is that the Graft CP-HA-K polymer can increase the re

关键词： Viscosity breaker Heat resistance Base mud Graft CP-HA-K polymer CP Salt resistance

Bilayer Compounded Polytetrafluoroethylene Membrane for Enhanced Oil-Water Emulsion Separation

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chinese Journal of Polymer Science 2024年第6期42卷 838-850页

作者： Yu-Liang yang tai-Ran Zhang yan-Ting Han Shao-Yun Guo Qin-Gong Rong Jia-Bin Shen State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversitySichuan Provincial Engineering Laboratory of Plastic/Rubber Complex Processing TechnologyChengdu610065China West china Hospital/West china School of Nursing Sichuan UniversityChengdu610041China Shandong Senrong New Materials Co. Ltd.Zibo256401China

In order to achieve efficient and durable oil-water emulsion separation,the membranes possessing high separation efficiency and mechanical strength attract extensive attention and are in great *** present study,a kind of polytetrafluoroethylene(PTFE)-based bilayer membrane was fabricated by electrospinning fibrous PTFE(fPTFE)on an expanded PTFE(ePTFE)*** morphological observation revealed that the fibrous structure of the fPTFE layer could be tailored by controlling the formulation of spinning *** addition of appropriate polyoxyethylene(PEO)would make the fibers in the fPTFE layer finer and more *** a result,the compounded membrane exhibited a small pore size of approximately 1.25µm and a substantial porosity nearing 80%.This led to super-hydrophobicity,characterized by a high water contact angle(WCA)of 149.8°,and facilitated rapid oil *** water-in-oil emulsion separation experiment further confirmed that the compounded membrane not only had a high separation efficiency closing 100%,but such an outstanding separation capacity could be largely retained,either through multiple cycles of use or through strong acid(pH=1),strong alkali(pH=12),or high-temperature(100°C)***,the mechanical behavior of the bilayer membrane was basically contributed by that of each layer in terms of their volume *** significantly,the poor creep resistance of fPTFE layer was suppressed by compounding with ePTFE ***,this study has laid the groundwork for a novel approach to create PTFE-based compounded membranes with exceptional overall characteristics,showing promise for applications in the realm of emulsion separation.

关键词： ePTFE Electrospinning membrane Bilayer compounding Emulsion separation

Regioselective cation exchange reaction for photoelectrochemical water splitting

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Rare Metals 2024年第7期43卷 3400-3407页

作者： Mo-yan Chen tai-Song Zhang Zhi yan Jiang-Nan Lv Xiao-Ting Sun Rui-Xia yang Mark TSwihart Xiao-Hong Xu yang Liu Research Institute of Materials Science of Shanxi Normal University&Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education Taiyuan 030031China Department of Chemical and Biological Engineering University at Buffalo(SUNY)NY 14260USA Department of Materials Science Fudan UniversityShanghai 200433China

Engineering copper sulfide-based heterostructures via cation exchange(CE)is an appealing approach,as it allows selective combination of distinct compositions and functions of metal *** heterostructures can play a significant role in photoelectrochemical applications,but the effect of the ratio between two or more domains in such heterostructures on the photoresponse has not been well explored.

关键词： exchange sulfide splitting

Reliability ensemble averaging reduces surface wind speed projection uncertainties in the 21st century over china

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Advances in Climate Change Research 2024年第2期15卷 222-229页

作者： Zheng-tai ZHANG Chang-Ai XU Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou UniversityLanzhou 730000China

Accurate prediction of future surface wind speed(SWS)changes is the basis of scientific planning for wind *** studies have projected SWS changes in the 21st century over china on the basis of the multi-model ensemble(MME)of the 6th Coupled Model Intercomparison Project(CMIP6).However,the simulation capability for SWS varies greatly in CMIP6 multi-models,so the MME results still have large *** this study,we used the reliability ensemble averaging(REA)method to assign each model different weights according to their performances in simulating historical SWS changes and project the SWS under different shared socioeconomic pathways(SSPs)in *** results indicate that REA considerably improves the SWS simulation capacity of CMIP6,eliminating the overestimation of SWS by the MME and increasing the simulation capacity of spatial *** spatial correlations with observations increased from 0.56 for the MME to 0.85 for ***,REA could eliminate the overestimation of the SWS by 33%in *** for southeastern china,the SWS generally decreases over china in the near term(2020-2049)and later term(2070-2099),particularly under high-emission *** SWS reduction projected by REA is twice as high as that by the MME in the near term,reaching-4%to-3%.REA predicts a larger area of increased SWS in the later term,which expands from southeastern china to eastern *** study helps to reduce the projected SWS uncertainties.

关键词： Surface wind speed Uncertainty Multi-model ensemble Reliability ensemble averaging CMIP6

Assessment and control of the mine tremor disaster induced by the energy accumulation and dispersion of thick-hard roofs

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International Journal of Mining Science and Technology 2024年第7期34卷 925-941页

作者： Bin Yu Mingxian Peng yang tai Shuai Guo State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China School of Resources and Safety Engineering Chongqing UniversityChongqing 400044China School of Mines China University of Mining and TechnologyXuzhou 221116China

In order to solve the problem that current theory models cannot accurately describe thick-hard roof(THR)elastic energy and assess the mine tremor disasters,a theoretical method,a Timoshenko beam theory on Winkler foundation was adopted to establish the THR’s periodic breaking *** superposition principle was used for this complex model to derive the calculation formulas of the elastic energy and impact load on hydraulic ***,the influence of roof thickness h,cantilever length L_(1),and load q on THR’s elastic energy and impact load was ***,the effect of mine tremor disasters was ***,it is revealed that:(1)The THR’s elastic energy U exhibits power-law variations,with the fitted relationships U=0.0096L_(1)^(3.5866^),U=5943.9h^(-1.935),and U=21.049q^(2).(2)The impact load on hydraulic supports F_(ZJ) increases linearly with an increase in the cantilever length,thickness,and applied *** fitted relationships are F_(ZJ)=1067.3L_(1)+6361.1,F_(ZJ)=125.89h+15100,and F_(ZJ)=10420q+3912.6.(3)Ground hydraulic fracturing and liquid explosive deep-hole blasting techniques effectively reduce the THR’s cantilever length at periodic breakages,thus eliminating mine tremor disasters.

关键词： Dynamic disaster Energy Hard and thick roof Timoshenko beam

NOX4 promotes tumor progression through the MAPK-MEK1/2-ERK1/2 axis in colorectal cancer

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1421-1436页

作者： Yu-Jie Xu Ya-Chang Huo Qi-tai Zhao Jin-yan Liu Yi-Jun Tian Lei-Lei yang Yi Zhang Biotherapy Center and Cancer Center The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Department of Oncology Henan Provincial People’s HospitalPeople’s Hospital of Zhengzhou UniversityPeople’s Hospital of Henan UniversityZhengzhou 450003Henan ProvinceChina

BACKGROUND Metabolic reprogramming plays a key role in cancer progression and clinical outcomes;however,the patterns and primary regulators of metabolic reprogramming in colorectal cancer(CRC)are not well *** To explore the role of nicotinamide adenine dinucleotide phosphate oxidase 4(NOX4)in promoting progression of *** We evaluated the expression and function of dysregulated and survival-related metabolic genes using Gene Ontology and Kyoto Encyclopedia of Genes and *** clustering was used to cluster CRC based on dysregulated metabolic genes.A prediction model was constructed based on survival-related metabolic *** formation,migration,invasion,proliferation,apoptosis and clone formation was used to evaluate the biological function of NOX4 in *** sequencing was utilized to explore the alterations of gene expression NOX4 over-expression tumor *** vivo subcutaneous and lung metastasis mouse tumor model was used to explore the effect of NOX4 on tumor *** We comprehensively analyzed 3341 metabolic genes in CRC and identified three clusters based on dysregulated metabolic *** these genes,NOX4 was highly expressed in tumor tissues and correlated with worse *** vitro,NOX4 overexpression induced clone formation,migration,invasion,and stemness in CRC ***,RNA-sequencing analysis revealed that NOX4 overexpression activated the mitogen-activated protein kinase-MEK1/2-ERK1/2 signaling ***,a MEK1/2 inhibitor,abolished the NOX4-mediated tumor *** vivo,NOX4 overexpression promoted subcutaneous tumor growth and lung metastasis,whereas trametinib treatment can reversed the *** Our study comprehensively analyzed metabolic gene expression and highlighted the importance of NOX4 in promoting CRC metastasis,suggesting that trametinib could be a potential therapeutic drugs of CRC clinical therapy targeting NOX4.

关键词： Colorectal cancer Metabolic reprogramming Metastasis Nicotinamide adenine dinucleotide phosphate oxidase 4 Mitogen-activated protein kinase signaling