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FedCLCC:A personalized federated learning algorithm for edge cloud collaboration based on contrastive learning and conditional computing
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作者 Kangning Yin Xinhui Ji +1 位作者 Yan Wang Zhiguo Wang 《Defence Technology(防务技术)》 2025年第1期80-93,共14页
Federated learning(FL)is a distributed machine learning paradigm for edge cloud computing.FL can facilitate data-driven decision-making in tactical scenarios,effectively addressing both data volume and infrastructure ... Federated learning(FL)is a distributed machine learning paradigm for edge cloud computing.FL can facilitate data-driven decision-making in tactical scenarios,effectively addressing both data volume and infrastructure challenges in edge environments.However,the diversity of clients in edge cloud computing presents significant challenges for FL.Personalized federated learning(pFL)received considerable attention in recent years.One example of pFL involves exploiting the global and local information in the local model.Current pFL algorithms experience limitations such as slow convergence speed,catastrophic forgetting,and poor performance in complex tasks,which still have significant shortcomings compared to the centralized learning.To achieve high pFL performance,we propose FedCLCC:Federated Contrastive Learning and Conditional Computing.The core of FedCLCC is the use of contrastive learning and conditional computing.Contrastive learning determines the feature representation similarity to adjust the local model.Conditional computing separates the global and local information and feeds it to their corresponding heads for global and local handling.Our comprehensive experiments demonstrate that FedCLCC outperforms other state-of-the-art FL algorithms. 展开更多
关键词 Federated learning Statistical heterogeneity Personalized model conditional computing Contrastive learning
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Optimal Receiver Operating Characteristic Curve of Classical Conditional Power under Normal Models
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作者 ZHANG Ying-Ying 《应用概率统计》 北大核心 2025年第2期277-304,共28页
A Receiver Operating Characteristic(ROC)analysis of a power is important and useful in clinical trials.A Classical Conditional Power(CCP)is a probability of a classical rejection region given values of true treatment ... A Receiver Operating Characteristic(ROC)analysis of a power is important and useful in clinical trials.A Classical Conditional Power(CCP)is a probability of a classical rejection region given values of true treatment effect and interim result.For hypotheses and reversed hypotheses under normal models,we obtain analytical expressions of the ROC curves of the CCP,find optimal ROC curves of the CCP,investigate the superiority of the ROC curves of the CCP,calculate critical values of the False Positive Rate(FPR),True Positive Rate(TPR),and cutoff of the optimal CCP,and give go/no go decisions at the interim of the optimal CCP.In addition,extensive numerical experiments are carried out to exemplify our theoretical results.Finally,a real data example is performed to illustrate the go/no go decisions of the optimal CCP. 展开更多
关键词 area under the curve(AUC) classical conditional power(CCP) go/no go decisions historical and interim data receiver operating characteristic(ROC)curve
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Censored Composite Conditional Quantile Screening for High-Dimensional Survival Data
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作者 LIU Wei LI Yingqiu 《应用概率统计》 CSCD 北大核心 2024年第5期783-799,共17页
In this paper,we introduce the censored composite conditional quantile coefficient(cC-CQC)to rank the relative importance of each predictor in high-dimensional censored regression.The cCCQC takes advantage of all usef... In this paper,we introduce the censored composite conditional quantile coefficient(cC-CQC)to rank the relative importance of each predictor in high-dimensional censored regression.The cCCQC takes advantage of all useful information across quantiles and can detect nonlinear effects including interactions and heterogeneity,effectively.Furthermore,the proposed screening method based on cCCQC is robust to the existence of outliers and enjoys the sure screening property.Simulation results demonstrate that the proposed method performs competitively on survival datasets of high-dimensional predictors,particularly when the variables are highly correlated. 展开更多
关键词 high-dimensional survival data censored composite conditional quantile coefficient sure screening property rank consistency property
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The Effects of Different Hydrothermal Preparation Conditions on the Properties of ZnO Nano-materials
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作者 XIA Ziwen LIANG Ping +3 位作者 FENG Yang YANG Weiye PENG Hongyan ZHAO Shihua 《材料导报》 北大核心 2025年第16期15-26,共12页
ZnO is a highly significant II-VI semiconductor known for its excellent optoelectronic properties,making it widely applicable and promising for use in light-emitting devices,solar cells,lasers,and photodetectors.The m... ZnO is a highly significant II-VI semiconductor known for its excellent optoelectronic properties,making it widely applicable and promising for use in light-emitting devices,solar cells,lasers,and photodetectors.The methods for preparing ZnO are diverse,and among them,the hydrothermal method is favored for its simplicity,ease of operation,and low cost,making it an optimal choice for ZnO single-crystal growth.Most studies investigating the effects of different hydrothermal experimental parameters on the morphology and performance of ZnO nano-materials typically focus on only 2—3 variable parameters,with few examining the impact of all possible experimental parameter changes on ZnO nano-mate-rials.The principles of the hydrothermal method and its advantages in nano-material preparation were briefly introduced in this article.The detailed discussion on the influence of various experimental parameters on the preparation of ZnO nano-materials was provided,which including reaction materials,Zn^(2+)/OH^(-)ratio,reaction time and temperature,additives,experimental equipment,and annealing conditions.The review co-vers how different experimental parameters affect the morphology and performance of the materials,as well as how different rare earth doping elements influence the performance of ZnO nano-materials.It is hoped that this work will contribute to future research on the hydrothermal synthesis of nano-materials. 展开更多
关键词 hydrothermal method reaction condition ZNO DOPING nano-material crystalline structureH
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A novel conditional cell transmission model for oversaturated arterials 被引量:3
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作者 王屏 L.S.Jones 杨群 《Journal of Central South University》 SCIE EI CAS 2012年第5期1466-1474,共9页
The objective of this work is to develop a novel feature for traffic flow models, when traffic queues on two-way arterials periodically extend until then they block an upstream signal in oversaturated conditions. The ... The objective of this work is to develop a novel feature for traffic flow models, when traffic queues on two-way arterials periodically extend until then they block an upstream signal in oversaturated conditions. The new model, proposed as conditional cell transmission model (CCTM) has been developed with two improvements. First, cell transmission model (CTM) is expanded for two-way arterials by taking account of all diverging and merging activities at intersections. Second, a conditional cell is added to simulate periodic spillback and blockages at an intersection. The results of experiments for a multilane, two-way, three-signal sample network demonstrate that CCTM can accommodate various traffic demands and accurate representation of blockages at intersections. The delay of left turns is underestimated by 40 % in moderate conditions and by 58% in oversamrated condition when using the CTM rather than CCTM. Finally, the consistency between HCS 2000 and CCTM shows that CCTM is a reliable methodology of modeling traffic flow in oversaturated condition. 展开更多
关键词 oversaturated condition conditional cell transmission model INTERSECTION spillback traffic blockage
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Sensitivity analysis of key input parameters in conditional cell transmission model for oversaturated arterials 被引量:2
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作者 王屏 S.L.JONES +1 位作者 杨群 S.GURUPACKIAM 《Journal of Central South University》 SCIE EI CAS 2013年第6期1772-1780,共9页
A novel conditional cell transmission model (CCTM) is a potential simulation tool because it accommodates all traffic conditions from light condition to oversaturated condition. To test the performance of the CCTM, ... A novel conditional cell transmission model (CCTM) is a potential simulation tool because it accommodates all traffic conditions from light condition to oversaturated condition. To test the performance of the CCTM, a series of experiments for sensitivity analysis were designed and performed for a multilane, two-way, three-signal sample network. Experiment 1 shows that the model is performed in a logical and expected manner with variations in traffic demand with time and direction. Experiment 2 shows when the possibility of the occurrence of a useful gap increases to 60% and 100%, the delays in left rams decrease by 5% and 15%, respectively. In Experiment 3, comparing the possibility of a conditional cell of 0 with 100%, delay of left turn and delay of the entire network were underestimated by 58% and 11%, respectively. Hence, sensitivity analysis demonstrates that by reflecting local drivers' behaviors properly, the CCTM provides an accurate representation of traffic flow in simulating oversaturated traffic conditions. 展开更多
关键词 oversaturation conditional cell transmission model sensitivity analysis DELAY POSSIBILITY
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Improving autoencoder-based unsupervised damage detection in uncontrolled structural health monitoring under noisy conditions 被引量:1
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作者 Yang Kang Wang Linyuan +4 位作者 Gao Chao Chen Mozhi Tian Zhihui Zhou Dunzhi Liu Yang 《仪器仪表学报》 EI CAS CSCD 北大核心 2024年第6期91-100,共10页
Structural health monitoring is widely utilized in outdoor environments,especially under harsh conditions,which can introduce noise into the monitoring system.Therefore,designing an effective denoising strategy to enh... Structural health monitoring is widely utilized in outdoor environments,especially under harsh conditions,which can introduce noise into the monitoring system.Therefore,designing an effective denoising strategy to enhance the performance of guided wave damage detection in noisy environments is crucial.This paper introduces a local temporal principal component analysis(PCA)reconstruction approach for denoising guided waves prior to implementing unsupervised damage detection,achieved through novel autoencoder-based reconstruction.Experimental results demonstrate that the proposed denoising method significantly enhances damage detection performance when guided waves are contaminated by noise,with SNR values ranging from 10 to-5 dB.Following the implementation of the proposed denoising approach,the AUC score can elevate from 0.65 to 0.96 when dealing with guided waves corrputed by noise at a level of-5 dB.Additionally,the paper provides guidance on selecting the appropriate number of components used in the denoising PCA reconstruction,aiding in the optimization of the damage detection in noisy conditions. 展开更多
关键词 structural health monitoring guided waves principal component analysis deep learning DENOISING dynamic environmental condition
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Automated pattern-directed refactoring for complex conditional statements
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作者 刘伟 胡志刚 +1 位作者 刘宏韬 杨柳 《Journal of Central South University》 SCIE EI CAS 2014年第5期1935-1945,共11页
Complex conditional statement is one of the bad code smells, which affects the quality of the code and design of software. In the proposed approach, two commonly-used design patterns for handling complex conditional s... Complex conditional statement is one of the bad code smells, which affects the quality of the code and design of software. In the proposed approach, two commonly-used design patterns for handling complex conditional statements are selected, and they are the factory method pattern and the strategy pattem. Two pattern-directed refactoring approaches based on the two design patterns are proposed. Each approach contains a refactoring opportunities identification algorithm and an automated refactoring algorithm. After parsing the abstract syntax tree generated from source code, the refactoring opportunities are identified effectively and automatically. Then, for candidate code, refactoring algorithms are executed automatically, which are used to simplify or remove complex conditional statements. By empirical analysis and quality assessment, the code after refactoring has better maintainability and extensibility, and the proposed approach for automated pattern-directed refactoring succeeds to reduce code size and complexity of classes. 展开更多
关键词 REFACTORING abstract syntax tree complex conditional statements design patterns factory method pattem strategypattem
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Role of outdoor trees on pedestrian wind and thermal conditions around a pre-education building for sustainable energy management
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作者 LI Xiao-jie TANG Hui-li 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2039-2053,共15页
Finding sustainable energy resources is essential to face the increasing energy demand.Trees are an important part of ancient architecture but are becoming rare in urban areas.Trees can control and tune the pedestrian... Finding sustainable energy resources is essential to face the increasing energy demand.Trees are an important part of ancient architecture but are becoming rare in urban areas.Trees can control and tune the pedestrian-level wind velocity and thermal condition.In this study,a numerical investigation is employed to assess the role of trees planted in the windward direction of the building complex on the thermal and pedestrian wind velocity conditions around/inside a pre-education building located in the center of the complex.Compared to the previous studies(which considered only outside buildings),this work considers the effects of trees on microclimate change both inside/outside buildings.Effects of different parameters including the leaf area density and number of trees,number of rows,far-field velocity magnitude,and thermal condition around the main building are assessed.The results show that the flow velocity in the spacing between the first-row buildings is reduced by 30%-40% when the one-row trees with 2 m height are planted 15 m farther than the buildings.Furthermore,two rows of trees are more effective in higher velocities and reduce the maximum velocity by about 50%.The investigation shows that trees also could reduce the temperature by about 1℃around the building. 展开更多
关键词 sustainable management energy trees urban area thermal condition building
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A review of extreme condition effects on solder joint reliability:Understanding failure mechanisms
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作者 Norliza Ismail Wan Yusmawati Wan Yusoff +2 位作者 Azuraida Amat Nor Azlian Abdul Manaf Nurazlin Ahmad 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第11期134-158,共25页
Solder joint,crucial component in electronic systems,face significant challenges when exposed to extreme conditions during applications.The solder joint reliability involving microstructure and mechanical properties w... Solder joint,crucial component in electronic systems,face significant challenges when exposed to extreme conditions during applications.The solder joint reliability involving microstructure and mechanical properties will be affected by extreme conditions.Understanding the behaviour of solder joints under extreme conditions is vital to determine the durability and reliability of solder joint.This review paper aims to comprehensively explore the underlying failure mechanism affecting solder joint reliability under extreme conditions.This study covers an in-depth analysis of effect extreme temperature,mechanical stress,and radiation conditions towards solder joint.Impact of each condition to the microstructure including solder matrix and intermetallic compound layer,and mechanical properties such as fatigue,shear strength,creep,and hardness was thoroughly discussed.The failure mechanisms were illustrated in graphical diagrams to ensure clarity and understanding.Furthermore,the paper highlighted mitigation strategies that enhancing solder joint reliability under challenging operating conditions.The findings offer valuable guidance for researchers,engineers,and practitioners involved in electronics,engineering,and related fields,fostering advancements in solder joint reliability and performance. 展开更多
关键词 Solder joint Extreme condition Failure mechanism Defence and military RELIABILITY
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老年健康查体人群中代谢相关共病及胰岛素抵抗与慢性肾脏病的相关性研究 被引量:1
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作者 杨光 程柏凯 +5 位作者 沈鑫 刘洋 丁影 程庆砾 郑延松 赵佳慧 《中华老年心脑血管病杂志》 北大核心 2025年第3期260-264,共5页
目的探讨老年健康查体人群中代谢相关共病、胰岛素抵抗(insulin resistance,IR)与慢性肾脏病(chronic kidney disease,CKD)之间的关系。方法纳入2009年12月至2021年5月在解放军总医院接受健康体检的老年人8358例,根据指南标准分为CKD组... 目的探讨老年健康查体人群中代谢相关共病、胰岛素抵抗(insulin resistance,IR)与慢性肾脏病(chronic kidney disease,CKD)之间的关系。方法纳入2009年12月至2021年5月在解放军总医院接受健康体检的老年人8358例,根据指南标准分为CKD组983例与非CKD组7375例。收集患者临床资料,计算IR指数估计的葡萄糖处置率(estimated glucose disposal rate,eGDR),应用Quasi-Bayesian进行因果中介分析。结果CKD组高血压、冠心病、糖尿病、高脂血症和高尿酸血症患病率显著高于非CKD组(P<0.01),CKD组eGDR显著低于非CKD组[(6.88±2.09)mg/(kg·min)vs(8.41±2.12)mg/(kg·min),P<0.01]。logistic回归分析结果显示,未调整协变量时,eGDR每增加1单位,CKD的发生风险降低29%(OR=0.714,95%CI:0.691~0.738,P<0.01)。调整后,eGDR与CKD风险仍显著相关(P<0.01)。中介分析显示,糖尿病和肱踝脉搏波传导速度在eGDR与CKD之间关系的中介效应占比最高(分别为14.2%和12.5%)。结论老年健康查体人群中胰岛素敏感性的降低与CKD的发生显著相关。糖尿病和动脉硬化在这一关联中起到中介作用。 展开更多
关键词 慢性病共病 代谢疾病 胰岛素抵抗 数据相关性
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基于大数据的继电保护运维管理系统的设计与实现 被引量:4
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作者 戴志辉 耿宏贤 +3 位作者 刘媛 吴道钰 刘悦 杨鑫 《电测与仪表》 北大核心 2025年第1期80-88,共9页
在双碳背景下,促进清洁能源消纳与碳减排已成为电网发展的重要目标。提出了一种优化方法,考虑可再生能源不确定性与系统功率储备进行系统调度。在预测误差分析的基础上,提出了一种基于负荷损失概率的评估方法,以确定系统运行储备功率。... 在双碳背景下,促进清洁能源消纳与碳减排已成为电网发展的重要目标。提出了一种优化方法,考虑可再生能源不确定性与系统功率储备进行系统调度。在预测误差分析的基础上,提出了一种基于负荷损失概率的评估方法,以确定系统运行储备功率。将系统运营成本和二氧化碳排放量建模为优化目标。优化过程包括两个阶段,在第一阶段优化中利用混合整数线性规划方法进行确定性优化,生成具有规定功率储备要求的发电机组组合。在第二阶段优化中考虑预测不确定性,对运行计划进行调整,使用可控发电机来处理预测偏差。将不同方法下可用运行储备功率、成本和二氧化碳排放量在仿真中进行了对比。与传统大数据技术及智能电网的发展为继电保护系统历史数据进行深层次挖掘提供了支撑,以此为基础研究了基于大数据的继电保护运维管理系统。文章针对基于大数据的继电保护运维管理系统进行设计,详细阐述了系统架构、数据库设计、系统功能模块、系统实现。系统在原始数据预处理的基础上进行数据可视化,从统计分析和动态分析两个角度对保护设备进行评估,实现了设备失效数据的统计计算、设备缺陷关联性分析、运行水平评估以及设备状态检修功能。系统实现了继电保护设备运维全流程管理,最终服务于继电保护检修工作,能够为运行人员状态检修提供参考,对于减小维修的盲目性、提高检修工作效率具有参考价值。 展开更多
关键词 继电保护 ACCESS数据库 关联规则 可靠度函数 状态检修
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基于玉米播种的无人驾驶电动拖拉机设计试验
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作者 李珊珊 吴正开 +4 位作者 王家忠 孔德刚 袁永伟 刘江涛 王泽河 《农机化研究》 北大核心 2025年第3期247-253,共7页
针对传统拖拉机进行玉米播种时作业直线度差、播种过程中动力传递不平稳的问题,设计了一台特征滑移率下牵引力超过10 kN的无人驾驶电动拖拉机。首先,根据玉米播种农艺和播种作业要求,设计无人驾驶电动拖拉机播种机组整机架构、拖拉机的... 针对传统拖拉机进行玉米播种时作业直线度差、播种过程中动力传递不平稳的问题,设计了一台特征滑移率下牵引力超过10 kN的无人驾驶电动拖拉机。首先,根据玉米播种农艺和播种作业要求,设计无人驾驶电动拖拉机播种机组整机架构、拖拉机的软件和能量传递架构;然后,分析无人驾驶电动拖拉机常见作业工况下的动力需求,根据开沟阻力计算关键部件功率需求,得到整机参数;最后,进行行走、播种工况试验测试,验证车辆性能。试验结果表明:在行走工况中,特征滑移率下的牵引动力为10 417 N,满足设计要求;电压、电流稳定输出,横向偏差在5 cm之内,满足作业要求。在播种工况下,特征滑移率下牵引动力为11 491 N,播种出苗后,苗直线度偏差在5 cm之内,满足农艺要求。标准工况下,动力电池单体在不同温度下稳定放电,电池以1 C放电时,容量在5~100 A·h之间能稳定运行,符合农业作业标准。 展开更多
关键词 无人驾驶电动拖拉机 玉米播种 行走工况 播种工况
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我国边疆区情特点与边疆治理现代化 被引量:2
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作者 方盛举 《人民论坛·学术前沿》 北大核心 2025年第10期28-38,共11页
全面深刻地认识我国边疆的区情特点是做好边疆治理各项工作的前提条件。边疆区情是指我国9个边疆省区在经济、政治、社会等领域的整体发展状况。边疆区情对边疆治理的科学决策具有决定性影响,对边疆治理客体的准确界定具有重大影响,对... 全面深刻地认识我国边疆的区情特点是做好边疆治理各项工作的前提条件。边疆区情是指我国9个边疆省区在经济、政治、社会等领域的整体发展状况。边疆区情对边疆治理的科学决策具有决定性影响,对边疆治理客体的准确界定具有重大影响,对深入推进边疆治理体系和治理能力现代化具有直接影响。边疆区情分为基本区情和现实区情。我国边疆基本区情包含涉边、涉外、涉族、涉教、涉贫等5个方面。我国边疆现实区情具体表现为处于市场体系边缘、交通体系末梢、开放体系末端,人才集中度较低、社会发育程度较低、地缘政治环境复杂、公共服务水平偏弱、生态环境脆弱易损等。根据边疆区情的特点,可以科学准确地界定新时代边疆治理的重点和难点,为我国边疆治理实践提供清晰的目标导向。 展开更多
关键词 边疆 边疆治理 基本区情 现实区情 边疆治理现代化
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产蛋白酶高温菌株筛选及豆粕固态发酵条件优化 被引量:1
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作者 张军燕 张焕新 +4 位作者 吴平 刘萍 黄延莉 代春华 何荣海 《中国粮油学报》 北大核心 2025年第1期84-89,共6页
从云烟卷烟中分离纯化后得到1株产蛋白酶能力较强的高温菌株YYC4。经16S rRNA基因序列分子生物学鉴定该菌株为地衣芽孢杆菌(Bacillus licheniformis)。通过单因素和响应面优化确定YYC4菌株高温固态发酵未灭菌豆粕的最佳条件为:料液比1∶... 从云烟卷烟中分离纯化后得到1株产蛋白酶能力较强的高温菌株YYC4。经16S rRNA基因序列分子生物学鉴定该菌株为地衣芽孢杆菌(Bacillus licheniformis)。通过单因素和响应面优化确定YYC4菌株高温固态发酵未灭菌豆粕的最佳条件为:料液比1∶1.80 g/mL、发酵温度55℃、接种量10^(7)CFU/g含水基质、相对湿度80%、发酵时间50 h、MgSO_(4)质量分数0.12%。在此条件下发酵,豆粕可溶性蛋白质量分数由4.92%升高至18.57%,总蛋白质量分数由40.42%增加至47.95%,胰蛋白酶抑制剂质量分数则由8.19 mg/kg降低至3.19 mg/kg。 展开更多
关键词 豆粕 高温固态发酵 菌株筛选 发酵条件优化
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一种基于预训练的条件文本生成方法
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作者 邵党国 孔宪媛 +3 位作者 马磊 安青 黄琨 相艳 《中文信息学报》 北大核心 2025年第7期127-137,共11页
随着电子商务的发展,人们需要从产品的评论中更加全面地了解产品信息,高质量的评论文本对于客户黏度和社会舆论发挥着重要作用。传统的中文文本生成模型表现良好,却不能有效结合先验知识并根据条件情感输入生成对应情感极性的文本。该... 随着电子商务的发展,人们需要从产品的评论中更加全面地了解产品信息,高质量的评论文本对于客户黏度和社会舆论发挥着重要作用。传统的中文文本生成模型表现良好,却不能有效结合先验知识并根据条件情感输入生成对应情感极性的文本。该文提出一种条件评论文本生成模型,将预训练语言模型与生成对抗网络结合起来,利用预训练模型较好的语言理解能力学习真实文本中概率分布。该文通过在生成器层标准化中引入条件层标准化,达到根据输入情感标签自动生成对应情感极性文本的目的。在电商评论数据集上的实验表明,该模型相较于传统的Seq2Seq模型和SeqGAN模型,不仅引入条件情感输入,并且生成效果更优、文本质量更高。 展开更多
关键词 BERT SeqGAN 条件层标准化 条件文本生成
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深部金属矿异构环境爆破开采诱发岩体动力灾害防控 被引量:2
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作者 周子龙 王少锋 +2 位作者 蔡鑫 黄英华 赵聪聪 《中国有色金属学报》 北大核心 2025年第1期306-322,共17页
战略性矿产资源为国民生产和国防建设提供重要物质基础,其供给保障直接关系国计民生与国家安全。地下金属矿山作为战略性金属矿产资源供给的主阵地,快速向深部延伸。深部金属矿山多采场多中段作业在地下形成了结构不连续、材料非均质、... 战略性矿产资源为国民生产和国防建设提供重要物质基础,其供给保障直接关系国计民生与国家安全。地下金属矿山作为战略性金属矿产资源供给的主阵地,快速向深部延伸。深部金属矿山多采场多中段作业在地下形成了结构不连续、材料非均质、应力非均匀的复杂异构环境。在这种环境下,爆破等开采扰动极易诱发岩体失稳进而引发岩爆、大规模坍塌等动力灾害,严重制约深部金属矿山安全高效可持续开发。因此,针对深部金属矿山存在的变异应力场、复杂岩体结构、强动力扰动等特点,亟需开展深部金属矿异构环境开采诱发岩体动力灾害防控理论与技术研究,获得异构环境下动力扰动诱发高应力岩体动态失稳规律,阐明深部异构环境下关键结构体的应力变化、动态损伤、裂纹扩展和能量耗散特性,揭示爆破应力波诱发深部异构区域高储能岩体灾变机制,构建以动静能量为指标的爆破诱发深部高储能岩体动力灾害判据,提出异构环境改良调控和高储能岩体精细化爆破主导有序破裂控制的深部金属矿复杂异构环境岩体动力灾害综合防控新模式,为深部金属矿山安全高效开采和灾害防控提供理论与技术支撑。 展开更多
关键词 深部金属矿 异构环境 爆破 岩体动力灾害 灾害防控
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不同土壤条件对蓝莓果实品质和产量的影响 被引量:1
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作者 秦洪波 郭伦发 +2 位作者 张怡彬 潘燕林 王新桂 《湖北农业科学》 2025年第4期118-121,共4页
以3年生南高丛蓝莓品种绿宝石为研究对象,通过正交试验设置了土壤pH、有机肥施用量和珍珠岩施用量3个因素,探究不同土壤条件对蓝莓果实品质和产量的影响。结果表明,不同土壤条件对蓝莓果实品质和产量存在显著影响。其中,在土壤pH 4.2、... 以3年生南高丛蓝莓品种绿宝石为研究对象,通过正交试验设置了土壤pH、有机肥施用量和珍珠岩施用量3个因素,探究不同土壤条件对蓝莓果实品质和产量的影响。结果表明,不同土壤条件对蓝莓果实品质和产量存在显著影响。其中,在土壤pH 4.2、园土∶有机肥∶珍珠岩=33.6∶4∶1(质量比)条件下,平均单株结果数达127.00个,平均单果重为2.31 g,平均果实横径为1.69 cm,平均单株产量为293.03 g,结果数量和单株产量显著高于其他处理。在土壤pH 5.8、园土∶有机肥∶珍珠岩=31.7∶6∶1(质量比)条件下蓝莓果实可溶性糖含量最高;在土壤pH为5.0、园土∶有机肥∶珍珠岩=63.3∶12∶1(质量比)条件下蓝莓果实花青素含量最高;空白对照的各项指标均处于最低值。 展开更多
关键词 蓝莓 土壤条件 果实品质 产量
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鄂尔多斯盆地本溪组煤岩气含气性主控因素及其实践意义 被引量:1
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作者 邓泽 赵群 +5 位作者 范立勇 黄道军 丁蓉 曹毅民 李珮杰 高向东 《煤炭科学技术》 北大核心 2025年第S1期233-251,共19页
鄂尔多斯盆地煤岩气资源丰富,多个区块勘探开发取得重大突破,然而煤岩气的含气性主控因素尚未明确,制约整体勘探开发进程。基于含气量、煤岩煤质、煤岩地化、孔隙结构等大量实测资料,系统分析了本溪组煤岩气地质条件,厘定了含气性主控因... 鄂尔多斯盆地煤岩气资源丰富,多个区块勘探开发取得重大突破,然而煤岩气的含气性主控因素尚未明确,制约整体勘探开发进程。基于含气量、煤岩煤质、煤岩地化、孔隙结构等大量实测资料,系统分析了本溪组煤岩气地质条件,厘定了含气性主控因素,并开展了煤岩气资源条件分区评价。研究表明:沉积、煤阶、埋深奠定了深层煤岩含气量的整体格局。①沉积环境制约着煤岩生烃物质基础(包括煤层厚度、煤层结构及煤岩煤质)、煤岩气原始赋存空间及保存条件的平面分布。成煤环境演化则决定了煤岩煤质的纵向差异分布,进而影响含气量的纵向非均质性。②煤阶不仅控制了煤岩生气强度,还通过影响孔裂隙结构从而影响煤岩气的赋存空间及储集性能。随着变质程度提高,煤岩的吸附性能得到了强化。③现今埋深主要影响吸附气和游离气的比例,常压储层在临界深度以下,随着埋深的增加,游离气的比例有所增加,3000 m以深总气量呈减小趋势。④微幅构造对发育于缓坡带的煤岩气起到了局部富气的作用。⑤综合考虑生、储、保有利条件,明确了盆地煤岩气富集带为榆林到宜川的南北条带,平均含气量高达23 cm^(3)/g。⑥依据煤岩气的内涵及含气性主控因素,结合煤层展布,构建了煤岩气资源条件评价体系,将盆地本溪组煤岩划分为4大类13个小区,Ⅰ类区主要分布在榆林地区、大宁—吉县地区和延安地区,Ⅱ类区主要分布在乌审旗一带。研究成果以期为鄂尔多斯盆地煤岩气有序勘探开发提供借鉴与参考。 展开更多
关键词 煤岩气 主控因素 资源条件 本溪组 鄂尔多斯盆地
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创新生态系统视角下区域协同创新效率提升的组态路径研究 被引量:4
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作者 孙燕芳 张淑惠 王勇 《统计与信息论坛》 北大核心 2025年第4期89-100,共12页
新发展阶段区域创新系统强调产学研创新主体间的协同互补和价值共创,同时国内外理论分析中均默认了创新生态系统在区域创新发展中的正面作用。因此,构建创新生态系统、提升区域产学研协同创新效率对深入实施国家创新驱动发展战略具有重... 新发展阶段区域创新系统强调产学研创新主体间的协同互补和价值共创,同时国内外理论分析中均默认了创新生态系统在区域创新发展中的正面作用。因此,构建创新生态系统、提升区域产学研协同创新效率对深入实施国家创新驱动发展战略具有重要意义。以2011—2022年中国30个省份数据为样本,选取创新生态视角下6个关键变量,以基于产学研协同的区域创新效率为结果,运用必要条件分析(NCA)与动态定性比较分析(QCA)相结合的方法识别产生结果的多条等效组态路径及其阶段性动态演化规律。研究发现:第一,创新主体、创新环境和创新资源共生耦合、协同作用才可产生区域高效协同创新,具有“殊途同归”的特点,具体表现为“环境—资源双重驱动型”和“互联网助力下的主体—资源驱动型”两类模式共3条组态路径;第二,其他因素相同时,前因条件或条件组合之间存在潜在替代关系,体现出区域创新生态系统与协同创新效率之间的“因果复杂性”;第三,在多时段比较分析中,区域高协同创新效率组态路径存在着动态演化,数字化创新和开放式创新将成为未来发展方向。研究结论有助于拓展区域产学研协同创新研究的理论视角,为相关管理者实现本地高效协同创新提供多种可供选择的差异化路径。 展开更多
关键词 创新生态系统 协同创新效率 定性比较分析 必要条件分析 组态路径
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