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Stress-assisted corrosion mechanism of 3Ni steel by using gradient boosting decision tree machining learning method 被引量:2
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作者 Xiaojia Yang Jinghuan Jia +5 位作者 Qing Li Renzheng Zhu Jike Yang Zhiyong Liu Xuequn Cheng Xiaogang Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1311-1321,共11页
Traditional 3Ni weathering steel cannot completely meet the requirements for offshore engineering development,resulting in the design of novel 3Ni steel with the addition of microalloy elements such as Mn or Nb for st... Traditional 3Ni weathering steel cannot completely meet the requirements for offshore engineering development,resulting in the design of novel 3Ni steel with the addition of microalloy elements such as Mn or Nb for strength enhancement becoming a trend.The stress-assisted corrosion behavior of a novel designed high-strength 3Ni steel was investigated in the current study using the corrosion big data method.The information on the corrosion process was recorded using the galvanic corrosion current monitoring method.The gradi-ent boosting decision tree(GBDT)machine learning method was used to mine the corrosion mechanism,and the importance of the struc-ture factor was investigated.Field exposure tests were conducted to verify the calculated results using the GBDT method.Results indic-ated that the GBDT method can be effectively used to study the influence of structural factors on the corrosion process of 3Ni steel.Dif-ferent mechanisms for the addition of Mn and Cu to the stress-assisted corrosion of 3Ni steel suggested that Mn and Cu have no obvious effect on the corrosion rate of non-stressed 3Ni steel during the early stage of corrosion.When the corrosion reached a stable state,the in-crease in Mn element content increased the corrosion rate of 3Ni steel,while Cu reduced this rate.In the presence of stress,the increase in Mn element content and Cu addition can inhibit the corrosion process.The corrosion law of outdoor-exposed 3Ni steel is consistent with the law based on corrosion big data technology,verifying the reliability of the big data evaluation method and data prediction model selection. 展开更多
关键词 weathering steel stress-assisted corrosion gradient boosting decision tree machining learning
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Nontraditional energy-assisted mechanical machining of difficult-to-cut materials and components in aerospace community:a comparative analysis 被引量:2
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作者 Guolong Zhao Biao Zhao +5 位作者 Wenfeng Ding Lianjia Xin Zhiwen Nian Jianhao Peng Ning He Jiuhua Xu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期190-271,共82页
The aerospace community widely uses difficult-to-cut materials,such as titanium alloys,high-temperature alloys,metal/ceramic/polymer matrix composites,hard and brittle materials,and geometrically complex components,su... The aerospace community widely uses difficult-to-cut materials,such as titanium alloys,high-temperature alloys,metal/ceramic/polymer matrix composites,hard and brittle materials,and geometrically complex components,such as thin-walled structures,microchannels,and complex surfaces.Mechanical machining is the main material removal process for the vast majority of aerospace components.However,many problems exist,including severe and rapid tool wear,low machining efficiency,and poor surface integrity.Nontraditional energy-assisted mechanical machining is a hybrid process that uses nontraditional energies(vibration,laser,electricity,etc)to improve the machinability of local materials and decrease the burden of mechanical machining.This provides a feasible and promising method to improve the material removal rate and surface quality,reduce process forces,and prolong tool life.However,systematic reviews of this technology are lacking with respect to the current research status and development direction.This paper reviews the recent progress in the nontraditional energy-assisted mechanical machining of difficult-to-cut materials and components in the aerospace community.In addition,this paper focuses on the processing principles,material responses under nontraditional energy,resultant forces and temperatures,material removal mechanisms,and applications of these processes,including vibration-,laser-,electric-,magnetic-,chemical-,advanced coolant-,and hybrid nontraditional energy-assisted mechanical machining.Finally,a comprehensive summary of the principles,advantages,and limitations of each hybrid process is provided,and future perspectives on forward design,device development,and sustainability of nontraditional energy-assisted mechanical machining processes are discussed. 展开更多
关键词 difficult-to-cut materials geometrically complex components nontraditional energy mechanical machining aerospace community
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Sentiment Analysis Using E-Commerce Review Keyword-Generated Image with a Hybrid Machine Learning-Based Model
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作者 Jiawen Li Yuesheng Huang +3 位作者 Yayi Lu Leijun Wang Yongqi Ren Rongjun Chen 《Computers, Materials & Continua》 SCIE EI 2024年第7期1581-1599,共19页
In the context of the accelerated pace of daily life and the development of e-commerce,online shopping is a mainstreamway for consumers to access products and services.To understand their emotional expressions in faci... In the context of the accelerated pace of daily life and the development of e-commerce,online shopping is a mainstreamway for consumers to access products and services.To understand their emotional expressions in facing different shopping experience scenarios,this paper presents a sentiment analysis method that combines the ecommerce reviewkeyword-generated imagewith a hybrid machine learning-basedmodel,inwhich theWord2Vec-TextRank is used to extract keywords that act as the inputs for generating the related images by generative Artificial Intelligence(AI).Subsequently,a hybrid Convolutional Neural Network and Support Vector Machine(CNNSVM)model is applied for sentiment classification of those keyword-generated images.For method validation,the data randomly comprised of 5000 reviews from Amazon have been analyzed.With superior keyword extraction capability,the proposedmethod achieves impressive results on sentiment classification with a remarkable accuracy of up to 97.13%.Such performance demonstrates its advantages by using the text-to-image approach,providing a unique perspective for sentiment analysis in the e-commerce review data compared to the existing works.Thus,the proposed method enhances the reliability and insights of customer feedback surveys,which would also establish a novel direction in similar cases,such as social media monitoring and market trend research. 展开更多
关键词 Sentiment analysis keyword-generated image machine learning word2Vec-TextRank CNN-SVM
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On dry machining of AZ31B magnesium alloy using textured cutting tool inserts
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作者 Shailendra Pawanr Kapil Gupta 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1608-1618,共11页
Magnesium alloys have many advantages as lightweight materials for engineering applications,especially in the fields of automotive and aerospace.They undergo extensive cutting or machining while making products out of... Magnesium alloys have many advantages as lightweight materials for engineering applications,especially in the fields of automotive and aerospace.They undergo extensive cutting or machining while making products out of them.Dry cutting,a sustainable machining method,causes more friction and adhesion at the tool-chip interface.One of the promising solutions to this problem is cutting tool surface texturing,which can reduce tool wear and friction in dry cutting and improve machining performance.This paper aims to investigate the impact of dimple textures(made on the flank face of cutting inserts)on tool wear and chip morphology in the dry machining of AZ31B magnesium alloy.The results show that the cutting speed was the most significant factor affecting tool flank wear,followed by feed rate and cutting depth.The tool wear mechanism was examined using scanning electron microscope(SEM)images and energy dispersive X-ray spectroscopy(EDS)analysis reports,which showed that at low cutting speed,the main wear mechanism was abrasion,while at high speed,it was adhesion.The chips are discontinuous at low cutting speeds,while continuous at high cutting speeds.The dimple textured flank face cutting tools facilitate the dry machining of AZ31B magnesium alloy and contribute to ecological benefits. 展开更多
关键词 Magnesium alloy Dry machining Textured tools Flank wear SUSTAINABILITY
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Field-assisted machining of difficult-to-machine materials
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作者 Jianguo Zhang Zhengding Zheng +5 位作者 Kai Huang Chuangting Lin Weiqi Huang Xiao Chen Junfeng Xiao Jianfeng Xu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期39-89,共51页
Difficult-to-machine materials (DMMs) are extensively applied in critical fields such as aviation,semiconductor,biomedicine,and other key fields due to their excellent material properties.However,traditional machining... Difficult-to-machine materials (DMMs) are extensively applied in critical fields such as aviation,semiconductor,biomedicine,and other key fields due to their excellent material properties.However,traditional machining technologies often struggle to achieve ultra-precision with DMMs resulting from poor surface quality and low processing efficiency.In recent years,field-assisted machining (FAM) technology has emerged as a new generation of machining technology based on innovative principles such as laser heating,tool vibration,magnetic magnetization,and plasma modification,providing a new solution for improving the machinability of DMMs.This technology not only addresses these limitations of traditional machining methods,but also has become a hot topic of research in the domain of ultra-precision machining of DMMs.Many new methods and principles have been introduced and investigated one after another,yet few studies have presented a comprehensive analysis and summarization.To fill this gap and understand the development trend of FAM,this study provides an important overview of FAM,covering different assisted machining methods,application effects,mechanism analysis,and equipment design.The current deficiencies and future challenges of FAM are summarized to lay the foundation for the further development of multi-field hybrid assisted and intelligent FAM technologies. 展开更多
关键词 field-assisted machining difficult-to-machine materials materials removal mechanism surface integrity
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Comparative Analysis of Machine Learning Algorithms for Email Phishing Detection Using TF-IDF, Word2Vec, and BERT
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作者 Arar Al Tawil Laiali Almazaydeh +3 位作者 Doaa Qawasmeh Baraah Qawasmeh Mohammad Alshinwan Khaled Elleithy 《Computers, Materials & Continua》 SCIE EI 2024年第11期3395-3412,共18页
Cybercriminals often use fraudulent emails and fictitious email accounts to deceive individuals into disclosing confidential information,a practice known as phishing.This study utilizes three distinct methodologies,Te... Cybercriminals often use fraudulent emails and fictitious email accounts to deceive individuals into disclosing confidential information,a practice known as phishing.This study utilizes three distinct methodologies,Term Frequency-Inverse Document Frequency,Word2Vec,and Bidirectional Encoder Representations from Transform-ers,to evaluate the effectiveness of various machine learning algorithms in detecting phishing attacks.The study uses feature extraction methods to assess the performance of Logistic Regression,Decision Tree,Random Forest,and Multilayer Perceptron algorithms.The best results for each classifier using Term Frequency-Inverse Document Frequency were Multilayer Perceptron(Precision:0.98,Recall:0.98,F1-score:0.98,Accuracy:0.98).Word2Vec’s best results were Multilayer Perceptron(Precision:0.98,Recall:0.98,F1-score:0.98,Accuracy:0.98).The highest performance was achieved using the Bidirectional Encoder Representations from the Transformers model,with Precision,Recall,F1-score,and Accuracy all reaching 0.99.This study highlights how advanced pre-trained models,such as Bidirectional Encoder Representations from Transformers,can significantly enhance the accuracy and reliability of fraud detection systems. 展开更多
关键词 ATTACKS email phishing machine learning security representations from transformers(BERT) text classifeir natural language processing(NLP)
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A Contrastive Analysis of English and Chinese Idioms About Color Words & Their Cultural Connotations
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作者 WANG Hong-mei 《Sino-US English Teaching》 2024年第9期439-442,共4页
There are many idioms related to color words in English and Chinese.The use of color words in idioms adds beauty and vividness to the language.Due to the cultural differences,“color idioms”have gained different cult... There are many idioms related to color words in English and Chinese.The use of color words in idioms adds beauty and vividness to the language.Due to the cultural differences,“color idioms”have gained different cultural connotations with the development of English and Chinese languages.It is of great significance to accurately understand and grasp the meanings and differences of color-related idioms in Chinese and English.This paper intends to analyze and expound the cultural connotations of English and Chinese idioms related to several widely used basic color words with the aim of helping English learners know and use the idioms about color words better. 展开更多
关键词 idioms about color words cultural connotation contrastive analysis
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Translation of Culture-loaded Words in The Golden Cangue under the Perspective of Reception Aesthetics
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作者 YU Xuan 《Journal of Literature and Art Studies》 2024年第6期468-473,共6页
Good translations play a very important role in cultural exchange.The idea of reception aesthetics think the reader as the center in translation process.This paper will study the translation of culture-loaded words fr... Good translations play a very important role in cultural exchange.The idea of reception aesthetics think the reader as the center in translation process.This paper will study the translation of culture-loaded words from the perspective of reception aesthetics.It is divided into five parts.The first part mainly introduces the background and theoretical foundation of this paper,the second part introduces the writer’s works,the third part gives examples to analyze the culture-loaded words appearing in The Golden Cangue,the fourth part gives examples of the translation methods,and the fifth part is the conclusion.It aims to provide a reference for the English translation of culture-loaded words. 展开更多
关键词 Culture-loaded words Reception Aesthetic The Golden Cangue Eileen Chang
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Machine learning applications in healthcare clinical practice and research
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作者 Nikolaos-Achilleas Arkoudis Stavros P Papadakos 《World Journal of Clinical Cases》 SCIE 2025年第1期16-21,共6页
Machine learning(ML)is a type of artificial intelligence that assists computers in the acquisition of knowledge through data analysis,thus creating machines that can complete tasks otherwise requiring human intelligen... Machine learning(ML)is a type of artificial intelligence that assists computers in the acquisition of knowledge through data analysis,thus creating machines that can complete tasks otherwise requiring human intelligence.Among its various applications,it has proven groundbreaking in healthcare as well,both in clinical practice and research.In this editorial,we succinctly introduce ML applications and present a study,featured in the latest issue of the World Journal of Clinical Cases.The authors of this study conducted an analysis using both multiple linear regression(MLR)and ML methods to investigate the significant factors that may impact the estimated glomerular filtration rate in healthy women with and without non-alcoholic fatty liver disease(NAFLD).Their results implicated age as the most important determining factor in both groups,followed by lactic dehydrogenase,uric acid,forced expiratory volume in one second,and albumin.In addition,for the NAFLD-group,the 5th and 6th most important impact factors were thyroid-stimulating hormone and systolic blood pressure,as compared to plasma calcium and body fat for the NAFLD+group.However,the study's distinctive contribution lies in its adoption of ML methodologies,showcasing their superiority over traditional statistical approaches(herein MLR),thereby highlighting the potential of ML to represent an invaluable advanced adjunct tool in clinical practice and research. 展开更多
关键词 machine Learning Artificial INTELLIGENCE CLINICAL Practice RESEARCH Glomerular filtration rate Non-alcoholic fatty liver disease MEDICINE
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基于图像Bag-of-Words模型的无载体信息隐藏 被引量:47
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作者 周志立 曹燚 孙星明 《应用科学学报》 CAS CSCD 北大核心 2016年第5期527-536,共10页
介绍一种基于bag-of-words(BOW)模型的无载体信息隐藏方法.该方法使用BOW模型提取图像的视觉关键词(visual words,VW)以表达待隐藏的文本信息,从而实现文本信息在图像中的隐藏.首先使用BOW模型提取图像集中每幅图像的VW,构建文本信息的... 介绍一种基于bag-of-words(BOW)模型的无载体信息隐藏方法.该方法使用BOW模型提取图像的视觉关键词(visual words,VW)以表达待隐藏的文本信息,从而实现文本信息在图像中的隐藏.首先使用BOW模型提取图像集中每幅图像的VW,构建文本信息的关键词和VW的映射关系库;然后把每幅图像分为若干子图像,统计每一幅子图像的VW频数直方图,选择频数最高的VW表示该子图像;最后根据构建的文本关键词和子图像VW的映射关系库,搜索出与待隐藏文本信息存在映射关系的子图像序列,将含有这些子图像的图像作为含密图像进行传递.实验结果和分析表明,该隐藏算法在抗隐写分析、鲁棒性和安全性方面均有良好的表现. 展开更多
关键词 无载体信息隐藏 BAG of words模型 视觉词汇 图像搜索
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基于“bag of words”的视频匹配方法 被引量:10
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作者 李远宁 刘汀 +1 位作者 蒋树强 黄庆明 《通信学报》 EI CSCD 北大核心 2007年第12期147-151,共5页
提出了一种利用"bag of words"模型对视频内容进行建模和匹配的方法。通过量化视频帧的局部特征构建视觉关键词(visual words)辞典,将视频的子镜头表示成若干视觉关键词的集合。在此基础上构建基于子镜头的视觉关键词词组的... 提出了一种利用"bag of words"模型对视频内容进行建模和匹配的方法。通过量化视频帧的局部特征构建视觉关键词(visual words)辞典,将视频的子镜头表示成若干视觉关键词的集合。在此基础上构建基于子镜头的视觉关键词词组的倒排索引,用于视频片段的匹配和检索。这种方法保留了局部特征的显著性及其相对位置关系,而且有效地压缩了视频的表达,加速的视频的匹配和检索过程。实验结果表明,和已有方法相比,基于"bag of words"的视频匹配方法在大视频样本库上获得了更高的检索精度和检索速度。 展开更多
关键词 视频匹配 视觉关键词 BAG of words倒排索引
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Non-traditional Machining Techniques for Fabricating Metal Aerospace Filters 被引量:5
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作者 汪炜 朱荻 +1 位作者 D.M.Allen H.J.A.Almond 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第5期441-447,共7页
Thanks to recent advances in manufacturing technology, aerospace system designers have many more options to fabricate high-quality, low-weight, high-capacity, cost-effective filters. Aside from traditional methods suc... Thanks to recent advances in manufacturing technology, aerospace system designers have many more options to fabricate high-quality, low-weight, high-capacity, cost-effective filters. Aside from traditional methods such as stamping, drilling and milling, many new approaches have been widely used in filter-manufacturing practices on account of their increased processing abilities. How- ever, the restrictions on costs, the need for studying under stricter conditions such as in aggressive fluids, the complicity in design, the workability of materials, and others have made it difficult to choose a satisfactory method from the newly developed processes, such as, photochemical machining (PCM), photo electroforming (PEF) and laser beam machining (LBM) to produce small, inexpensive, lightweight aerospace filters. This article appraises the technical and economical viability of PCM, PEF, and LBM to help engineers choose the fittest approach to turn out aerospace filters. 展开更多
关键词 aerospace filter photochemical machining photo electroforming laser beam machining
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Aviation-oriented Micromachining Technology—Micro-ECM in Pure Water 被引量:1
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作者 鲍怀谦 徐家文 李颖 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第5期455-461,共7页
This article proposes a precise and ecofriendly micromachining technology for aerospace application called electrochemical machining in pure water (PW-ECM). On the basis of the principles of water dissociation, a se... This article proposes a precise and ecofriendly micromachining technology for aerospace application called electrochemical machining in pure water (PW-ECM). On the basis of the principles of water dissociation, a series of test setups and tests are devised and performed under different conditions. These tests explain the need for technological conditions realizing PW-ECM, and further explore the technological principles. The results from the tests demonstrate a successful removal of electrolytic slime by means of ultrasonic vibration of the workpiece. To ensure the stability and reliability of PW-ECM process, a new combined machining method of PW-ECM assisted with ultrasonic vibration (PW-ECM/USV) is devised. Trilateral and square cavities and holes as well as a group of English alphabets are worked out on a stainless steel plate. It is confirmed that PW-ECM will be probably an efficient new aviation precision machining method. 展开更多
关键词 electrochemical machining in pure water (PW-ECM) cation exchange membrane water dissociation
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MACHINING OF METAL MATRIX COMPOSITES 被引量:3
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作者 徐九华 左敦稳 杨明达 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第2期161-167,共7页
Two types of aluminium-based composites reinforced respectively with 20 vol short fibre alumina and with a hybrid of 15 vol SiC particle and 5 vol short alumina fibre are machined with different tool materials:cemente... Two types of aluminium-based composites reinforced respectively with 20 vol short fibre alumina and with a hybrid of 15 vol SiC particle and 5 vol short alumina fibre are machined with different tool materials:cemented carbide,ceramic,cubic boron nitride(CBN)and polycrystalline diamond(PCD).The analysis on tool wear shows that the various tool materials exhibite different tool wear behaviours,and the tool wear mechanisma are discussed.Apparently,PCD tools do not necessarily guarantee dimensional stability but they can provide the most economic means for machining all sorts of composites.Consequently,a suitable tool material is suggested for machining each metal matrix composite(MMC) from the standpoints of tool wear and machined surface finish. 展开更多
关键词 machining cutting force surface roughness metal matrix composite tool wear
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INTERNET-BASED MACHINING PARAMETER OPTIMIZATION AND MANAGEMENT SYSTEM FOR HIGH-SPEED MACHINING 被引量:5
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作者 武美萍 廖文和 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第1期42-46,共5页
The theory and its method of machining parameter optimization for high-speed machining are studied. The machining data collected from workshops, labs and references are analyzed. An optimization method based on the ge... The theory and its method of machining parameter optimization for high-speed machining are studied. The machining data collected from workshops, labs and references are analyzed. An optimization method based on the genetic algorithm (GA) is investigated. Its calculation speed is faster than that of traditional optimization methods, and it is suitable for the machining parameter optimization in the automatic manufacturing system. Based on the theoretical studies, a system of machining parameter management and optimization is developed. The system can improve productivity of the high-speed machining centers. 展开更多
关键词 computer aided manufacturing DATABASE genetic algorithm OPTIMIZATION numerical control machining
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Machining Line Planner输出STEP-NC数控程序的研究 被引量:1
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作者 樊留群 刘玉平 《制造技术与机床》 CSCD 北大核心 2010年第7期88-91,共4页
介绍了STEP-NC的概念、数据模型及其结构特点,然后通过对比MLP(Machining Line Planner)和STEP-NC数控程序对特征和操作的不同定义方法,分析了在MLP中特征及加工工艺与STEP-NC的对应关系,探讨了在MLP中实现输出STEP-NC格式的零件加工程... 介绍了STEP-NC的概念、数据模型及其结构特点,然后通过对比MLP(Machining Line Planner)和STEP-NC数控程序对特征和操作的不同定义方法,分析了在MLP中特征及加工工艺与STEP-NC的对应关系,探讨了在MLP中实现输出STEP-NC格式的零件加工程序的方法。 展开更多
关键词 STEP-NC数据模型 数控程序 machining LINE PLANNER
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PRECISION OF HSK TOOLING SYSTEM IN HIGH SPEED MACHINING 被引量:1
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作者 王贵成 吴卫国 +2 位作者 王树林 裴宏杰 沈春根 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第2期129-133,共5页
Based on the theory of elastic mechanics and material mechanics, the orientation precision of the hohl schaft kegel(HSK) tooling system in static and dynamic states is theoretically and experimentally studied. The r... Based on the theory of elastic mechanics and material mechanics, the orientation precision of the hohl schaft kegel(HSK) tooling system in static and dynamic states is theoretically and experimentally studied. The relation between the clamping force and the shank taper is obtained. And a proper clamping force is found to be essential to assure the axial and radial orientation precisions of the HSK tooling system in high speed machining (HSM). Analytical results show that the reason why the HSK tooling system can keep high precision at the high rotational speed is that the actual axial clamping force keeps the two surfaces of the shank and the spindle in contact all the time. 展开更多
关键词 high speed machining HSK tooling system orientation precision
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Comparative study of Chinese and English color words 被引量:2
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作者 李涛 《Sino-US English Teaching》 2008年第1期56-59,共4页
There are a lot of color words in both English and Chinese. The color words in both English and Chinese can be divided into two parts: basic color words and real-stuff based color words. In this paper the formation, ... There are a lot of color words in both English and Chinese. The color words in both English and Chinese can be divided into two parts: basic color words and real-stuff based color words. In this paper the formation, syntactic functions and characteristics of English and Chinese color words have been analytically studied, and some differences and similarities of English and Chinese color words have been summed up. 展开更多
关键词 basic color words real-stuff based color words similarity and difference
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Optimization of micro milling electrical discharge machining of Inconel 718 by Grey-Taguchi method 被引量:3
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作者 林茂用 曹中丞 +3 位作者 许春耀 邱蕙 黄鹏丞 林裕城 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第3期661-666,共6页
The optimization of micro milling electrical discharge machining(EDM) process parameters of Inconel 718 alloy to achieve multiple performance characteristics such as low electrode wear,high material removal rate and... The optimization of micro milling electrical discharge machining(EDM) process parameters of Inconel 718 alloy to achieve multiple performance characteristics such as low electrode wear,high material removal rate and low working gap was investigated by the Grey-Taguchi method.The influences of peak current,pulse on-time,pulse off-time and spark gap on electrode wear(EW),material removal rate(MRR) and working gap(WG) in the micro milling electrical discharge machining of Inconel 718 were analyzed.The experimental results show that the electrode wear decreases from 5.6×10-9 to 5.2×10-9 mm3/min,the material removal rate increases from 0.47×10-8 to 1.68×10-8 mm3/min,and the working gap decreases from 1.27 to 1.19 μm under optimal micro milling electrical discharge machining process parameters.Hence,it is clearly shown that multiple performance characteristics can be improved by using the Grey-Taguchi method. 展开更多
关键词 Inconel 718 alloy micro milling electrical discharge machining electrode wear material removal rate working gap Grey-Taguchi method
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n-words模型下Hesse稀疏表示的图像检索算法 被引量:2
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作者 王瑞霞 彭国华 《电子与信息学报》 EI CSCD 北大核心 2016年第5期1115-1122,共8页
论文针对视觉词袋(BOVW)模型放弃图像空间结构的缺点,提出一种基于Hesse稀疏编码的图像检索算法。首先,建立n-words模型,获得图像局部特征表示。n-words模型由一系列连续视觉词获得,是图像特征的一种高级描述。该文从n=1到n=5进行试验,... 论文针对视觉词袋(BOVW)模型放弃图像空间结构的缺点,提出一种基于Hesse稀疏编码的图像检索算法。首先,建立n-words模型,获得图像局部特征表示。n-words模型由一系列连续视觉词获得,是图像特征的一种高级描述。该文从n=1到n=5进行试验,寻找最恰当的n值;其次,将二阶Hesse能量函数融入标准稀疏编码的目标函数,得到Hesse稀疏编码公式;最后,以获得的n-words序列作为编码特征,利用特征符号搜索算法求解最优Hesse系数,计算相似度,返回检索结果。实验在两类数据集上进行,与BOVW模型和已有的算法相比,新算法极大地提高了图像检索的准确率。 展开更多
关键词 图像检索 稀疏编码 视觉词袋模型 n-words模型 Hesse能量函数
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