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Key regions where land surface processes shape the East Asian climate
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作者 Haishan Chen 《Atmospheric and Oceanic Science Letters》 CSCD 2022年第3期64-66,共3页
Land-atmosphere interaction,as one of the key processes affecting the atmosphere and climate over East Asia,has drawn increasing attention during the past few decades.However,the current level of understanding regardi... Land-atmosphere interaction,as one of the key processes affecting the atmosphere and climate over East Asia,has drawn increasing attention during the past few decades.However,the current level of understanding regarding the mechanisms through which land surface processes impact the East Asian climate needs to be improved.Based on existing studies,six key regions where land surface processes affect the East Asian climate are proposed in this study,which can provide a valuable reference for future research into land-atmosphere interaction in East Asia. 展开更多
关键词 Land surface process East Asian climate key regions
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基于粒子群优化模糊PID控制的水厂加氯系统 被引量:1
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作者 刘晓艳 宋浪 +2 位作者 汪恂 詹焕 谢世伟 《市政技术》 2024年第3期198-205,共8页
水厂加氯过程具有非线性、大时滞等特点,采用传统的PID控制方式难以实现消毒剂精准投加。因此,以某采用次氯酸钠消毒系统的水厂为例,首先通过分析该水厂加氯系统工作原理,结合工程经验和运行数据确定了加氯过程的近似数学模型。然后综... 水厂加氯过程具有非线性、大时滞等特点,采用传统的PID控制方式难以实现消毒剂精准投加。因此,以某采用次氯酸钠消毒系统的水厂为例,首先通过分析该水厂加氯系统工作原理,结合工程经验和运行数据确定了加氯过程的近似数学模型。然后综合使用粒子群优化算法、模糊控制算法和PID控制算法,设计了一种粒子群优化模糊PID控制器,并利用MATLAB软件搭建了粒子群优化模糊PID控制系统和传统PID控制系统的模型进行仿真验证,结果表明:相较于传统PID控制系统,粒子群优化模糊PID控制系统的超调量减少了89.36%,调节时间减少了46.63%,其抗干扰能力也更强,系统整体控制效果有了较大提升。最后使用基于粒子群优化的模糊PID控制法对水厂加氯控制系统进行改造,试运行后发现,新系统控制效果良好,出厂水游离氯值能够稳定在设定值附近。 展开更多
关键词 水厂 加氯系统 模糊控制 粒子群优化算法 PID控制
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纸张数字化图像处理与信息识别系统设计研究
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作者 王淼 毛莉君 +1 位作者 孙莉梅 王亚棉 《造纸科学与技术》 2024年第2期63-66,共4页
针对纸张信息识别领域的图像处理技术进行研究,可构建出一种纸张数字化图像处理与信息识别的系统,具体可从软件、硬件两方面对该系统进行分析。将数字化图像处理技术与信息识别两者结合可从纸张中获取有效的防伪信息,并对纸张进行真假辨... 针对纸张信息识别领域的图像处理技术进行研究,可构建出一种纸张数字化图像处理与信息识别的系统,具体可从软件、硬件两方面对该系统进行分析。将数字化图像处理技术与信息识别两者结合可从纸张中获取有效的防伪信息,并对纸张进行真假辨识,不仅可降低人工误检的现象,还可使检测的工作效率得到提升,而且适合数字化信息管理,同时可降低个人与企业的经济损失,符合现代社会的发展需求,有着重要的现实意义。 展开更多
关键词 防伪纸张 图像处理 功能纸张 信息识别
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基于HMM与SVM的运动跌倒预警模型研究——以安徽省老年群体为例
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作者 张瑞全 《绵阳师范学院学报》 2024年第5期128-134,共7页
人口老龄化问题日益加重,老年人的身体机能随着年龄的增加而降低.为提升运动跌倒预警的检测率和延长预留时间,提出基于HMM与SVM的运动跌倒预警模型,通过人体行为特征分析和判别算法设计实现运动跌倒的成功预测,并以安徽省老年群体为背景... 人口老龄化问题日益加重,老年人的身体机能随着年龄的增加而降低.为提升运动跌倒预警的检测率和延长预留时间,提出基于HMM与SVM的运动跌倒预警模型,通过人体行为特征分析和判别算法设计实现运动跌倒的成功预测,并以安徽省老年群体为背景,从中采集实验数据.实验结果表明,SVM模型的检测率为69.5%,基于HMM与SVM的运动跌倒预警模型的检测率为91%,对比结果表明基于HMM与SVM的运动跌倒预警模型针对突发情况的误判率较低,具备良好的泛化能力.基于HMM与SVM的运动跌倒预警模型检测的平均预留时间是245 ms,满足充气机构反应耗时,结果有助于老年人跌倒预警以及人体保护. 展开更多
关键词 跌倒预警 人体行为特征 姿态角 预警算法 判别流程 安徽省老年群体
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基于薄层色谱和指纹图谱的百合成分差异性研究
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作者 魏家保 唐双燕 +6 位作者 谢嘉慧 詹智洪 蔡素琴 黄凯伟 赵伟志 张辉 谭沛 《中国现代中药》 CAS 2024年第9期1503-1510,共8页
目的:建立卷丹、百合、细叶百合3个基原药材及对应蜜百合鉴别的薄层色谱法(TLC)和指纹图谱方法,对各基原药材所含有的化学成分进行差异性研究。方法:采用Ultimate XB C18色谱柱(250 mm×4.6 mm,5μm),以乙腈(A)-0.1%磷酸水溶液(B)... 目的:建立卷丹、百合、细叶百合3个基原药材及对应蜜百合鉴别的薄层色谱法(TLC)和指纹图谱方法,对各基原药材所含有的化学成分进行差异性研究。方法:采用Ultimate XB C18色谱柱(250 mm×4.6 mm,5μm),以乙腈(A)-0.1%磷酸水溶液(B)为流动相,梯度洗脱;建立21批不同基原百合药材高效液相色谱法指纹图谱,并进行相似度评价、聚类分析、主成分分析、正交偏最小二乘法-判别分析,评价不同基原百合的异同。同时采用硅胶G薄层色谱板,分别以乙酸乙酯-甲醇-甲酸-水(18∶2∶1.5∶1)、乙醚-正丁醇-冰乙酸(3∶9∶6)为展开剂,建立不同基原百合药材及蜜百合的薄层色谱区分方法,全面展现不同基原百合及蜜百合中化学成分特点。结果:指纹图谱结果显示,不同基原百合药材差异明显,卷丹、百合、细叶百合样品分别标定8、12、8个峰,共有成分为高泛酸、王百合苷H、王百合苷A,而王百合苷I存在于百合、细叶百合中,2-乙酰王百合苷A存在于卷丹中;不同基原百合的相似度评价结果(均小于0.50)显示其成分差异较大;经统计分析发现,不同基原百合分别聚为一类;峰12(2-乙酰王百合苷A)、峰13、峰14、峰11(王百合苷I)、峰3(高泛酸)是卷丹、百合、细叶百合的差异性成分。TLC结果表明,不同基原百合的色谱斑点存在明显差异,可与指纹图谱结果相互印证;而蜜百合TLC存在蔗糖、果糖、葡萄糖斑点,百合药材仅存在蔗糖斑点,这种成分差异来源于炼蜜。结论:所建立的指纹图谱及TLC可对百合药材进行质量评价,且能快速、准确、直观地反映不同基原百合药材及蜜百合中含有的成分差异,为不同基原百合药材和蜜百合的质量控制及区分鉴别提供参考。 展开更多
关键词 百合 蜜炙 不同基原 薄层色谱法 指纹图谱 区分鉴别
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Cost of Multicast Logical Key Tree Based on Hierarchical Data Processing 被引量:2
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作者 ZHOU Fucai XU Jian LI Ting 《Wuhan University Journal of Natural Sciences》 CAS 2006年第5期1172-1176,共5页
How to design a multicast key management system with high performance is a hot issue now. This paper will apply the idea of hierarchical data processing to construct a common analytic model based on directed logical k... How to design a multicast key management system with high performance is a hot issue now. This paper will apply the idea of hierarchical data processing to construct a common analytic model based on directed logical key tree and supply two important metrics to this problem: re-keying cost and key storage cost. The paper gives the basic theory to the hierarchical data processing and the analyzing model to multieast key management based on logical key tree. It has been proved that the 4-ray tree has the best performance in using these metrics. The key management problem is also investigated based on user probability model, and gives two evaluating parameters to re-keying and key storage cost. 展开更多
关键词 MULTICAST logical key tree hierarchical data processing
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Analysis of key technologies and development of integrated digital processing system for cast blasting design 被引量:2
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作者 丁小华 李克民 +1 位作者 肖双双 狐为民 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第3期1037-1044,共8页
Casting blast can greatly reduce the stripping cost and improve the production capacity of opencast coal mines. Key technologies including high bench blasting, inclined hole, millisecond blasting, pre-splitting blasti... Casting blast can greatly reduce the stripping cost and improve the production capacity of opencast coal mines. Key technologies including high bench blasting, inclined hole, millisecond blasting, pre-splitting blasting and casting blast parameters determination which have influence on the effect of casting blast have been researched with the combination of the ballistic theory and experience in mines. The integrated digital processing system of casting blast was developed in order to simplify the design process of casting blast, improve working efficiency and veracity of design result and comprehensively adopt the software programming method and the theory of casting blast. This system has achieved five functions, namely, the 3D visualization graphics management, the intelligent management of geological information, the intelligent design of casting blast, the analysis and prediction of the blasting effect and the automatic output of the design results. Long-term application in opencast coal mines has shown that research results can not only reduce the specific explosive consumption and improve the blasting effect, but also have high value of popularization and application. 展开更多
关键词 opencast coal mine cast blasting key technology digital processing system
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The integrated monitoring system for running parameters of key mining equipment based on condition monitoring technology 被引量:1
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作者 BIN Guang-fu LI Xue-jun +2 位作者 BALBIR S Dhillon HUANG Zhen-yu GUO Deng-ta 《Journal of Coal Science & Engineering(China)》 2010年第1期108-112,共5页
An integrated monitoring system for running parameters of key mining equipmenton the basis of condition monitoring technology and modern communication networktechnology was developed.The system consists of a client co... An integrated monitoring system for running parameters of key mining equipmenton the basis of condition monitoring technology and modern communication networktechnology was developed.The system consists of a client computer with functions ofsignal acquisition and processing, and a host computer in the central control room.Thesignal acquisition module of the client computer can collect the running parameters fromvarious monitoring terminals in real-time.The DSP high-speed data processing system ofthe main control module can quickly achieve the numerical calculation for the collectedsignal.The signal modulation and signal demodulation are completed by the frequencyshift keying circuit and phase-locked loop frequency circuit, respectively.Finally, the signalis sent to the host computer for logic estimation and diagnostic analysis using the networkcommunication technology, which is helpful for technicians and managers to control therunning state of equipment. 展开更多
关键词 mining key equipment running parameters condition monitoring signal acquisition and processing integrated monitoring
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Dalian University of Technology Key Laboratory of Special Processing of Raw Materials
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《China Foundry》 SCIE CAS 2005年第4期309-309,共1页
关键词 key Laboratory of Special Processing of Raw Materials Dalian University of Technology
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Biometric Signature of Private Key by Reliable Iris Recognition Based on Flexible-ICA Algorithm
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作者 Aissa Boukhari Salim Chitroub Imen Bouraoui 《International Journal of Communications, Network and System Sciences》 2011年第12期778-789,共12页
The numerical world is under a fast development generating facilities and threats. The recommended solutions are especially the protection of information in all its states. The levels of protection show a discrepancy ... The numerical world is under a fast development generating facilities and threats. The recommended solutions are especially the protection of information in all its states. The levels of protection show a discrepancy from an application to another;governmental, commercial or even cybercriminal. The infrastructure used in modern cryptography is based on public key cryptosystem. The problem is how to make safe the private key and to memorize it without difficulties and damages. This paper introduces a biometric solution of owner signature generating an encryption of the key using the iris recognition kept in a smart card. Several precautions were taken to guarantee the safety and the availability of the use of the private key. They are two essential goals to attest: the quality of the service and the robustness of suggested safety. Being the quality of the service, the used iris recognition is based on a new emerging method founded on Flexible-ICA algorithm. This method offers a better Equal Error rate compared to other methods previously used. This quality of recognition was also reinforced by an encoding of error using a flag and finally Reed Solomon encoder. For recommended safety, a scheme based on block encryption is used. The proposed scheme is Propagating Cipher Block chaining which offers a very propagation of a high level of confusion and diffusion. Indeed, the robustness of this cryptographic process was studied by setting up strict criteria of safety. 展开更多
关键词 Image Processing CRYPTOSYSTEM Public key IRIS Recognition Code REED SOLOMON Independent Component Analysis (ICA)
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Northwestern Polytechnical University State Key Laboratory of Solidification Processing
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《China Foundry》 SCIE CAS 2005年第1期75-75,共1页
关键词 Northwestern Polytechnical University State key Laboratory of Solidification Processing
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Innovation and Decision-making Management Key Manipulation
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作者 Baohui Zhang 《International Journal of Technology Management》 2014年第2期115-118,共4页
This thesis focuses on corporate decision-making and innovation as a process of the system as a whole. The innovative nature of the activities is to change the existing state of technology or management, and that re-c... This thesis focuses on corporate decision-making and innovation as a process of the system as a whole. The innovative nature of the activities is to change the existing state of technology or management, and that re-combination of factors of production or knowledge base of the organization. Decision-making and innovation is a concentrated expression of the entrepreneurial ability and achievements. Proposed an optimized model of decision-making and innovation, and for the first time put forward the concept of "decision-making innovation manipulation critical platform" and manipulation instructions, provide a guiding framework for corporate decision-making innovation and capacity building, and has a certain practical significance. 展开更多
关键词 innovation and decision-making process system the key manipulation
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Innovation and Decision-making Management Key Manipulation
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作者 Baohui Zhang Yuzhong Zhang 《International Journal of Technology Management》 2013年第3期76-79,共4页
This thesis focuses on corporate decision-making and innovation as a process of the system as a whole. The innovative nature of the activities is to change the existing state of technology or management, and that re-c... This thesis focuses on corporate decision-making and innovation as a process of the system as a whole. The innovative nature of the activities is to change the existing state of technology or management, and that re-combination of factors of production or knowledge base of the organization. Decision-making and innovation is a concentrated expression of the entrepreneurial ability and achievements. Proposed an optimized model of decision-making and innovation, and for the first time put forward the concept of "decision-making innovation manipulation critical platform" and manipulation instructions, provide a guiding framework for corporate decision-making innovation and capacity building, and has a certain practical significance. 展开更多
关键词 innovation and decision-making process system the key manipulation
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SIP Key Process Technology trend
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《电子工业专用设备》 2006年第8期I0028-I0033,共6页
关键词 SIP key Process Technology trend
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解钾JX-10菌的筛选及解钾工艺
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作者 薛永萍 肖春桥 +1 位作者 张琰图 池汝安 《矿产综合利用》 CAS 北大核心 2023年第2期17-23,共7页
本文从一钾长石矿区土壤中分离、筛选得到了6株高效解钾细菌。其中命名为JX-10的菌株分离于矿区茼蒿根系土壤,经基因测序鉴定为Bacillus sp.,与KT981886菌相似度高到99.72%。同时就培养时间、温度及转速等解钾工艺条件进行了探讨。实验... 本文从一钾长石矿区土壤中分离、筛选得到了6株高效解钾细菌。其中命名为JX-10的菌株分离于矿区茼蒿根系土壤,经基因测序鉴定为Bacillus sp.,与KT981886菌相似度高到99.72%。同时就培养时间、温度及转速等解钾工艺条件进行了探讨。实验结果表明,JX-10菌株具有分解钾长石矿物的能力。其较佳解钾工艺条件为:培养温度28℃、时间10 d,转速160 r/min,培养基pH值为5.0,钾长石浓度2 g/L,粒度0.03mm,接种量25%,硫酸铵浓度0.2 g/L。在较佳工艺条件下,溶液中可溶性钾离子含量可达23.32 mg/L,浸出率为8.36%。 展开更多
关键词 解钾菌 筛选 鉴定 工艺优化
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化工工艺的风险识别与安全评价研究 被引量:1
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作者 邹昌锴 《山西化工》 CAS 2023年第11期194-196,共3页
许多工业生产推进都需基于化学工业,因此化工工艺的控制也是重点,在整个工艺生产中需经过许多复杂环节,隐藏着各种类型的危险因素,使得化学工艺具有高风险性,一旦发生事故,所造成的损失无法估量。探析了化工工艺风险识别工作的关键要点... 许多工业生产推进都需基于化学工业,因此化工工艺的控制也是重点,在整个工艺生产中需经过许多复杂环节,隐藏着各种类型的危险因素,使得化学工艺具有高风险性,一旦发生事故,所造成的损失无法估量。探析了化工工艺风险识别工作的关键要点,围绕着生产原材料、工艺反应流程以及工艺设备等多维度进行研究,提出了化工工艺安全评价的方法。 展开更多
关键词 安全评价 化工工艺风险 识别
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基于子空间方法的航站楼安检队列状态预测
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作者 秦倩 丁新伟 +1 位作者 邢志伟 凌若鸿 《计算机仿真》 北大核心 2023年第8期72-77,482,共7页
针对大型繁忙机场旅客安检服务效率低的问题,结合航班时刻及离港旅客属性,提出基于子空间辨识的航站楼安检队列状态预测模型。模型结合安检场景特点,在子空间辨识方法基础上,通过训练大量历史数据设定安检队列初始状态,并根据机场繁忙... 针对大型繁忙机场旅客安检服务效率低的问题,结合航班时刻及离港旅客属性,提出基于子空间辨识的航站楼安检队列状态预测模型。模型结合安检场景特点,在子空间辨识方法基础上,通过训练大量历史数据设定安检队列初始状态,并根据机场繁忙度与旅客流量特征对安检数据进行分组,对分组数据分别辨识获取不同特征下的系统矩阵,构建多特征模型。使用国内某大型机场安检数据对模型进行检验,结果表明模型在误差允许范围内的预测准确率较高,且有较好的稳定性。 展开更多
关键词 机场旅客安检 预测模型 安检排队 子空间辨识 队列状态
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MSCT及图像后处理技术在腹股沟疝诊断中的应用价值分析
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作者 陈国章 《中华养生保健》 2023年第1期15-19,共5页
目的探讨在腹股沟疝诊断中多层螺旋CT(MSCT)及图像后处理技术的应用价值。方法回顾性分析2018年6月~2021年12月海西州人民医院收治的60例疑似腹股沟疝患者的临床资料,对其开展MSCT及图像后处理技术检查,以手术病理检查作为金标准,评估M... 目的探讨在腹股沟疝诊断中多层螺旋CT(MSCT)及图像后处理技术的应用价值。方法回顾性分析2018年6月~2021年12月海西州人民医院收治的60例疑似腹股沟疝患者的临床资料,对其开展MSCT及图像后处理技术检查,以手术病理检查作为金标准,评估MSCT及图像后处理技术的检出率、诊断准确率、灵敏度、特异度,同时分析影像学表现。结果经MSCT及图像后处理技术检查检出率、诊断准确率、灵敏度、特异度均较高,与金标准具有一致性;MSCT图像后处理技术下,横断位和矢状位诊断的准确率经比较,差异无统计学意义(P>0.05);MSCT及图像后处理技术检查病囊的直径与病理结果一致。结论MSCT及图像后处理技术在腹股沟疝诊断中的检查结果与术后诊断结果一致性较高,能够为临床医师提供重要的诊断依据,指导临床确定个性化的手术方案。 展开更多
关键词 腹股沟疝 诊断 鉴别 MSCT及图像后处理技术 应用价值
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玉米种子活力图像识别与处理技术研究 被引量:18
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作者 赵新子 吴巍 +1 位作者 司秀丽 袁洪印 《吉林农业大学学报》 CAS CSCD 北大核心 2004年第5期572-576,共5页
运用图像处理硬件系统、图像识别与处理技术(图像预处理和图像分析等)对2000—2002年收获的玉米杂交种"吉单180"、自交系"莫17"和"四4112"分别进行了种子活力检测。结果表明:计算机检测结果对四唑染色法... 运用图像处理硬件系统、图像识别与处理技术(图像预处理和图像分析等)对2000—2002年收获的玉米杂交种"吉单180"、自交系"莫17"和"四4112"分别进行了种子活力检测。结果表明:计算机检测结果对四唑染色法人工测定结果平均准确度达93 7%以上。 展开更多
关键词 玉米种子 活力 四唑染色法 图像识别与处理
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羊绒与羊毛纤维表面形态的图像处理与识别 被引量:25
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作者 杨建忠 王荣武 《毛纺科技》 CAS 北大核心 2002年第5期12-15,共4页
分析了羊绒和羊毛的表面鳞片形态特征 ,综合利用灰度差值、模板代换、边界搜索、轮廓跟踪、拐点分析等一系列图像处理和识别的方法 ,对羊绒和羊毛表面鳞片形态进行处理 ,提出了鳞片内外 2个方形因子的指标 ,对羊绒纤维实现了自动的识别。
关键词 图像识别 羊绒 羊毛纤维 表面形态 图像处理
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