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基于Prototype反向蒸馏的无监督多类别异常检测
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作者 何立仁 彭博 池明旻 《计算机科学》 北大核心 2025年第2期202-211,共10页
无监督异常检测因只需要正常样本进行训练而被广泛应用于工业质检等领域。直接将现有的单类别异常检测方法应用到多类别异常检测中会导致性能显著下降,其中基于知识蒸馏的异常检测方法将预训练的教师模型关于正常样本的特征知识蒸馏到... 无监督异常检测因只需要正常样本进行训练而被广泛应用于工业质检等领域。直接将现有的单类别异常检测方法应用到多类别异常检测中会导致性能显著下降,其中基于知识蒸馏的异常检测方法将预训练的教师模型关于正常样本的特征知识蒸馏到学生模型中,然而它们在多类别异常检测中存在无法保证学生模型只学习到正常样本知识的问题。文中提出一种基于反向知识蒸馏框架的无监督多类别异常检测方法(Prototype based Reverse Distillation,PRD),其通过Multi-class Normal Prototype模块和Sparse Prototype Recall训练策略来学习教师模型关于多类别正常样本特征的Prototype,并以此来过滤学生模型的输入特征,从而确保学生模型只学习到教师模型关于正常样本的特征知识。PRD在多种工业异常检测数据集上性能均超越了现有的SOTA方法,定性、定量和消融实验验证了PRD整体框架和内部模块的有效性。 展开更多
关键词 异常检测 无监督学习 prototype学习 知识蒸馏 预训练特征
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PPFormer:Patch Prototype Transformer for Semantic Segmentation
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作者 Shanyuan Liu Yonggang Lu 《Journal of Beijing Institute of Technology》 2025年第4期405-417,共13页
Since the introduction of vision Transformers into the computer vision field,many vision tasks such as semantic segmentation tasks,have undergone radical changes.Although Transformer enhances the correlation of each l... Since the introduction of vision Transformers into the computer vision field,many vision tasks such as semantic segmentation tasks,have undergone radical changes.Although Transformer enhances the correlation of each local feature of an image object in the hidden space through the attention mechanism,it is difficult for a segmentation head to accomplish the mask prediction for dense embedding of multi-category and multi-local features.We present patch prototype vision Transformer(PPFormer),a Transformer architecture for semantic segmentation based on knowledge-embedded patch prototypes.1)The hierarchical Transformer encoder can generate multi-scale and multi-layered patch features including seamless patch projection to obtain information of multiscale patches,and feature-clustered self-attention to enhance the interplay of multi-layered visual information with implicit position encodes.2)PPFormer utilizes a non-parametric prototype decoder to extract region observations which represent significant parts of the objects by unlearnable patch prototypes and then calculate similarity between patch prototypes and pixel embeddings.The proposed contrasting patch prototype alignment module,which uses new patch prototypes to update prototype bank,effectively maintains class boundaries for prototypes.For different application scenarios,we have launched PPFormer-S,PPFormer-M and PPFormer-L by expanding the scale.Experimental results demonstrate that PPFormer can outperform fully convolutional networks(FCN)-and attention-based semantic segmentation models on the PASCAL VOC 2012,ADE20k,and Cityscapes datasets. 展开更多
关键词 hierarchical backbones patch prototype nonparametric learning semantic segmentation
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kProtoClust:Towards Adaptive k-Prototype Clustering without Known k
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作者 Yuan Ping Huina Li +1 位作者 Chun Guo Bin Hao 《Computers, Materials & Continua》 2025年第3期4949-4976,共28页
Towards optimal k-prototype discovery,k-means-like algorithms give us inspirations of central samples collection,yet the unstable seed samples selection,the hypothesis of a circle-like pattern,and the unknown K are st... Towards optimal k-prototype discovery,k-means-like algorithms give us inspirations of central samples collection,yet the unstable seed samples selection,the hypothesis of a circle-like pattern,and the unknown K are still challenges,particularly for non-predetermined data patterns.We propose an adaptive k-prototype clustering method(kProtoClust)which launches cluster exploration with a sketchy division of K clusters and finds evidence for splitting and merging.On behalf of a group of data samples,support vectors and outliers from the perspective of support vector data description are not the appropriate candidates for prototypes,while inner samples become the first candidates for instability reduction of seeds.Different from the representation of samples in traditional,we extend sample selection by encouraging fictitious samples to emphasize the representativeness of patterns.To get out of the circle-like pattern limitation,we introduce a convex decomposition-based strategy of one-cluster-multiple-prototypes in which convex hulls of varying sizes are prototypes,and accurate connection analysis makes the support of arbitrary cluster shapes possible.Inspired by geometry,the three presented strategies make kProtoClust bypassing the K dependence well with the global and local position relationship analysis for data samples.Experimental results on twelve datasets of irregular cluster shape or high dimension suggest that kProtoClust handles arbitrary cluster shapes with prominent accuracy even without the prior knowledge K. 展开更多
关键词 prototype finding convex hull support vector data description geometrical information
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CPEWS:Contextual Prototype-Based End-to-End Weakly Supervised Semantic Segmentation
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作者 Xiaoyan Shao Jiaqi Han +2 位作者 Lingling Li Xuezhuan Zhao Jingjing Yan 《Computers, Materials & Continua》 2025年第4期595-617,共23页
The primary challenge in weakly supervised semantic segmentation is effectively leveraging weak annotations while minimizing the performance gap compared to fully supervised methods.End-to-end model designs have gaine... The primary challenge in weakly supervised semantic segmentation is effectively leveraging weak annotations while minimizing the performance gap compared to fully supervised methods.End-to-end model designs have gained significant attention for improving training efficiency.Most current algorithms rely on Convolutional Neural Networks(CNNs)for feature extraction.Although CNNs are proficient at capturing local features,they often struggle with global context,leading to incomplete and false Class Activation Mapping(CAM).To address these limitations,this work proposes a Contextual Prototype-Based End-to-End Weakly Supervised Semantic Segmentation(CPEWS)model,which improves feature extraction by utilizing the Vision Transformer(ViT).By incorporating its intermediate feature layers to preserve semantic information,this work introduces the Intermediate Supervised Module(ISM)to supervise the final layer’s output,reducing boundary ambiguity and mitigating issues related to incomplete activation.Additionally,the Contextual Prototype Module(CPM)generates class-specific prototypes,while the proposed Prototype Discrimination Loss and Superclass Suppression Loss guide the network’s training,(LPDL)(LSSL)effectively addressing false activation without the need for extra supervision.The CPEWS model proposed in this paper achieves state-of-the-art performance in end-to-end weakly supervised semantic segmentation without additional supervision.The validation set and test set Mean Intersection over Union(MIoU)of PASCAL VOC 2012 dataset achieved 69.8%and 72.6%,respectively.Compared with ToCo(pre trained weight ImageNet-1k),MIoU on the test set is 2.1%higher.In addition,MIoU reached 41.4%on the validation set of the MS COCO 2014 dataset. 展开更多
关键词 End-to-end weakly supervised semantic segmentation vision transformer contextual prototype class activation map
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An Energy Management System with Mobile Energy Station Based Wireless Energy Transfer:System Design and Prototype Implementation
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作者 Yan Kang Li Jinhui +3 位作者 Fan Xinyu Hu Jie Yu Qin Yang Kun 《China Communications》 2025年第1期89-101,共13页
In indoor environments,various batterypowered Internet of Things(IoT)devices,such as remote controllers and electronic tags on high-level shelves,require efficient energy management.However,manually monitoring remaini... In indoor environments,various batterypowered Internet of Things(IoT)devices,such as remote controllers and electronic tags on high-level shelves,require efficient energy management.However,manually monitoring remaining energy levels and battery replacement is both inadequate and costly.This paper introduces an energy management system for indoor IoT,which includes a mobile energy station(ES)for enabling on-demand wireless energy transfer(WET)in radio frequency(RF),some energy receivers(ERs),and a cloud server.By implementing a two-stage positioning system and embedding energy receivers into traditional IoT devices,we robustly manage their energy storage.The experimental results demonstrate that the energy receiver can harvest a minimum power of 58 mW. 展开更多
关键词 angle of arrival(AOA) Internet of Things(IoT) mobile station prototype wireless energy transfer(WET)
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PARAMETERIZED-PROTOTYPE-BASED DYNAMIC OPTIMIZATION DESIGN FOR CAM PROFILE 被引量:1
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作者 彭禹 郝志勇 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第4期310-316,共7页
Aiming at the problems in current cam profile optimization processes, such as simple dynamics models, limited geometric accuracy and low design automatization level, a new dynamic optimization mode is put forward. Bas... Aiming at the problems in current cam profile optimization processes, such as simple dynamics models, limited geometric accuracy and low design automatization level, a new dynamic optimization mode is put forward. Based on the parameterization modeling technique of MSC. ADAMS platform, the different steps in current mode are reorganized, thus obtaining an upgraded mode called the "parameterized-prototype-based cam profile dynamic optimization mode". A parameterized prototype(PP) of valve mechanism is constructed in the course of dynamic optimization for cam profiles. Practically, by utilizing PP and considering the flexibility of the parts in valve mechanism, geometric accuracy and design automatization are improved. 展开更多
关键词 valve mechanism cam profile optimization design parameterized prototype dynamic optimization
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Experimental Investigation on Basic Prototype of Solid Propellant Impulsive Microthrusters 被引量:1
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作者 李世鹏 张平 《Journal of Beijing Institute of Technology》 EI CAS 2000年第3期347-352,共6页
A new type of impulsive microthruster and its measurement system were designed for the aim of testing the performance of a basic prototype of solid propellant impulsive microthruster. Two sets of tests were conducted.... A new type of impulsive microthruster and its measurement system were designed for the aim of testing the performance of a basic prototype of solid propellant impulsive microthruster. Two sets of tests were conducted. The tests show that the ignitor and the main charge of the microthruster match well, the dynamic and static capability of the test and measurement meets the test requirement and the result is creditable. The measured technical characteristics of the microthruster are that the ignition delay time is shorter than 0 3?ms, the total impulse is over 3?N·s, the operational time is shorter than 16?ms and the mass ratio of the thruster is 0 216. 展开更多
关键词 solid propellant rocket motor microthruster prototype test and measurement technique
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基于K-prototypes的混合属性数据聚类算法 被引量:16
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作者 陈韡 王雷 蒋子云 《计算机应用》 CSCD 北大核心 2010年第8期2003-2005,2110,共4页
通过对基于K-prototypes算法对混合属性数据处理的聚类问题进行研究,改进了K-prototypes算法中分类属性相异度计算公式,使之能更加精确反映样本间的差异;在此基础上提出了一种用于处理混合属性数据的聚类算法,并将改进后的算法应用于英... 通过对基于K-prototypes算法对混合属性数据处理的聚类问题进行研究,改进了K-prototypes算法中分类属性相异度计算公式,使之能更加精确反映样本间的差异;在此基础上提出了一种用于处理混合属性数据的聚类算法,并将改进后的算法应用于英语借词数据的聚类分析中。实验结果表明,与K-prototypes算法相比,改进后的算法具有更好的稳定性和更高的精度。 展开更多
关键词 聚类 K-prototypes算法 混合属性数据 相异度
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基于K-prototype聚类的学生教育画像分析 被引量:20
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作者 翟鸣宇 程建 +1 位作者 王苏桐 王延章 《大连理工大学学报(社会科学版)》 CSSCI 北大核心 2021年第6期22-31,共10页
针对包含类别数据与数值数据的高校教育大数据,采用基于汉明距离与欧式距离混合度量的K-prototype进行聚类,并通过轮廓系数对聚类效果进行评价,与常用的k-means、DBSCAN进行对比,实验结果表明:基于K-prototype的聚类在教育大数据的处理... 针对包含类别数据与数值数据的高校教育大数据,采用基于汉明距离与欧式距离混合度量的K-prototype进行聚类,并通过轮廓系数对聚类效果进行评价,与常用的k-means、DBSCAN进行对比,实验结果表明:基于K-prototype的聚类在教育大数据的处理上更具优势。基于聚类结果,采用词云图构建了4类学生教育画像。画像从基本属性、生活消费、生活规律等维度将学生群体划分为“思想积极型学生”“夜猫子游戏型学生”“规律作息型学生”“节俭好学型学生”4类,为学生教育管理人员提供相应的决策支持。 展开更多
关键词 学生教育画像 K-prototype聚类 词云图
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一种增强的K-prototypes混合数据聚类算法 被引量:5
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作者 李顺勇 顾嘉成 《陕西科技大学学报》 北大核心 2021年第2期183-188,共6页
针对K-prototypes算法处理混合数据时精度不高等问题,提出了一种增强的K-prototypes混合数据聚类算法(An Enhanced K-prototypes Mixed Data Clustering Algorithm,EKPCA).首先定义了一种新的距离计算公式,扩大了数据之间的差异性,有利... 针对K-prototypes算法处理混合数据时精度不高等问题,提出了一种增强的K-prototypes混合数据聚类算法(An Enhanced K-prototypes Mixed Data Clustering Algorithm,EKPCA).首先定义了一种新的距离计算公式,扩大了数据之间的差异性,有利于对簇边缘数据进行合理划分;其次选取较多初始原型来覆盖数据的整体信息;最后迭代消去多余原型,得到数据集的真实分类.在8个UCI数据集上对算法进行评测,实验结果表明EKPCA算法有较高聚类精度. 展开更多
关键词 K-prototypes 混合数据 距离计算 初始原型 迭代消去
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模糊k-prototypes聚类算法的一种改进算法 被引量:11
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作者 王宇 杨莉 《大连理工大学学报》 EI CAS CSCD 北大核心 2003年第6期849-852,共4页
模糊k-prototypes算法是当前聚类分析中最有效算法之一.简述了模糊k-prototypes算法的发展进程和主要性质;并在此基础上,指出它在处理数值型和分类型混合数据时的不足,进而提出一种改进算法;最后,将算法应用到英语借词之中,给出计算结果... 模糊k-prototypes算法是当前聚类分析中最有效算法之一.简述了模糊k-prototypes算法的发展进程和主要性质;并在此基础上,指出它在处理数值型和分类型混合数据时的不足,进而提出一种改进算法;最后,将算法应用到英语借词之中,给出计算结果.结果表明,改进算法具有较好的稳定性和较高的精确度. 展开更多
关键词 模糊k-prototypes聚类算法 数值型属性 分类型属性 英语借词 数据挖掘
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Questionnaire Design and Analysis for the Influences of Prototype Landscape on One's Landscape Perception
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作者 王之婧 朱春阳 冯艺佳 《Journal of Landscape Research》 2010年第5期78-80,85,共4页
Prototype landscape refers to the impressive scenes that one has experienced in his/her living environment before 20 years old.Based on the analysis of the existing literature,the authors compiled a standard scale typ... Prototype landscape refers to the impressive scenes that one has experienced in his/her living environment before 20 years old.Based on the analysis of the existing literature,the authors compiled a standard scale type questionnaire by means of a field survey,which was about the influences of prototype landscape on one's landscape perception.Taking Likert scale as the main part,this questionnaire analyzed the influence of prototype landscape on landscape perception from perception,attitude,and behavior dimensions.In order to further improve its rationality,the authors tested some other aspects of this questionnaire,including logic validity,construct validity,congeniality reliability,split-half reliability,etc..The results validated that the questionnaire possessed good theoretical structure and validity target,which can evaluate various aspects of prototype landscape on one's landscape perception in an effective and reliable way.Therefore,the questionnaire put forward by this study not only enriched the studies of prototype landscape on landscape designing,but also provided an effective tool for quantitative analysis of "the influences of prototype landscape on one's landscape perception". 展开更多
关键词 COMPILING QUESTIONNAIRE prototype LANDSCAPE LANDSCAPE PERCEPTION Likert scale
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一种基于k-prototype的多层次聚类改进算法 被引量:1
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作者 李士进 朱跃龙 刘净 《河海大学学报(自然科学版)》 CAS CSCD 北大核心 2007年第3期342-347,共6页
针对k-prototype算法在处理复杂的数据集时,常出现一些纯度不高的簇,影响了聚类质量的问题,提出一种基于k-prototype的多层次聚类改进算法,利用属性自动选择的方法将一些纯度不高的簇进行再聚类,以提高聚类质量.以UCI标准测试数据集进... 针对k-prototype算法在处理复杂的数据集时,常出现一些纯度不高的簇,影响了聚类质量的问题,提出一种基于k-prototype的多层次聚类改进算法,利用属性自动选择的方法将一些纯度不高的簇进行再聚类,以提高聚类质量.以UCI标准测试数据集进行实验,实验结果表明,该改进算法能够明显提高混合型数据集的聚类质量,并且在数据约简方面有良好表现. 展开更多
关键词 聚类 混合数据 多层次聚类 k-prototype聚类
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Prototypes and Vocabulary Teaching
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作者 王乐 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2006年第S1期337-338,共2页
The prototype theory suggests that many metal concepts we have are really prototypes.It claims that children first learn words that are "basic" because they reflect aspects of the world,prototypes, which sta... The prototype theory suggests that many metal concepts we have are really prototypes.It claims that children first learn words that are "basic" because they reflect aspects of the world,prototypes, which stand out automatically from the rest of what they see.Basic level words should be taught first. 展开更多
关键词 prototype prototype theory prototype theory of vocabulary
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基于典型样本的Prototype决策树
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作者 何劲松 施泽生 《计算机工程与应用》 CSCD 北大核心 2001年第5期9-10,16,共3页
文章将SVM算法和GA-NN-C4.5算法的思路结合起来,提出了用典型样本产生原型(Prototype)的方法。实验结果表明,基于典型样本的Prototype决策树搜索效果更好、判决精度更高。
关键词 典型样本 prototype决策树 归纳学习 SVM算法 GA
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EFFECT OF TIME AND ENVIRONMENT ON THE DIMENSION PRECISION AND MASS OF LOM PROTOTYPES
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作者 张连洪 李华友 《Transactions of Tianjin University》 EI CAS 2001年第3期214-216,共3页
The effect of time and environment on the dimension precision and mass of LOM prototypes was experimentally investigated.It is to identify the stability of the dimension of LOM prototypes after forming.The results sho... The effect of time and environment on the dimension precision and mass of LOM prototypes was experimentally investigated.It is to identify the stability of the dimension of LOM prototypes after forming.The results show that the dimension and the mass tendency to grow,which is mainly caused by elastic recovery and moisture absorption and is characterized principally by the growth of Z dimension.Self restraint can be a significant factor to influence Z growth of LOM prototypes. 展开更多
关键词 laminated object manufacturing (LOM) time effect dimension stability rapid prototyping
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量子遗传算法的模糊K-prototypes聚类 被引量:1
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作者 叶奇明 梁根 《计算机工程与应用》 CSCD 北大核心 2010年第1期112-115,共4页
聚类分析是数据挖掘中应用最多的一种技术,它在许多领域都有重要应用。模糊h-prototypes算法是当前聚类分析中最有效算法之一,但是存在对初始值敏感、容易陷入局部极小值的问题。为了克服该缺点,提出了一种基于量子遗传算法和FKP算法的... 聚类分析是数据挖掘中应用最多的一种技术,它在许多领域都有重要应用。模糊h-prototypes算法是当前聚类分析中最有效算法之一,但是存在对初始值敏感、容易陷入局部极小值的问题。为了克服该缺点,提出了一种基于量子遗传算法和FKP算法的混合聚类算法,首先利用量子遗传算法确定FKP的初始聚类中心,再将量子遗传算法聚类结果作为后续FKP算法的初始值。实验结果显示,算法具有良好的收敛性和稳定性,聚类效果优于单一使用FKP算法和相关改进的算法。 展开更多
关键词 聚类算法 量子遗传算法 模糊K-prototypes算法 数值型属性 数据挖掘
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基于信息增益的模糊K-prototypes聚类算法
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作者 欧阳浩 王智文 +1 位作者 戴喜生 刘智琦 《计算机工程与科学》 CSCD 北大核心 2015年第5期1009-1014,共6页
K-prototypes聚类算法结合了K-means算法和K-modes算法,可用于分析混合属性的数据对象。传统的K-prototypes聚类算法在计算数据对象的相异度时,未考虑各个属性对于最终聚类结果的影响程度,而现实世界中,各属性的重要程度是不同的。使用... K-prototypes聚类算法结合了K-means算法和K-modes算法,可用于分析混合属性的数据对象。传统的K-prototypes聚类算法在计算数据对象的相异度时,未考虑各个属性对于最终聚类结果的影响程度,而现实世界中,各属性的重要程度是不同的。使用了信息论中信息增益的计算方法,来获得各个属性的权值。在计算各属性的差异度时,乘以这些权值,从而可以获得更为准确的聚类结果。为了增加算法处理模糊问题的能力,本算法引用了模糊理论,从而使其具有较好的抗干扰能力和处理不确定性问题的能力。通过对四个UCI数据集的聚类分析实验,表明了本算法的有效性。 展开更多
关键词 聚类 信息增益 模糊K-prototypes算法 混合型数据
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基于平均差异度的改进k-prototypes聚类算法 被引量:4
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作者 石鸿雁 徐明明 《沈阳工业大学学报》 EI CAS 北大核心 2019年第5期555-559,共5页
针对k-prototypes聚类算法随机选取初始聚类中心导致聚类结果不稳定,以及现有的大多数混合属性数据聚类算法聚类质量不高等问题,提出了基于平均差异度的改进k-prototypes聚类算法.通过利用平均差异度选取初始聚类中心,避免了初始聚类中... 针对k-prototypes聚类算法随机选取初始聚类中心导致聚类结果不稳定,以及现有的大多数混合属性数据聚类算法聚类质量不高等问题,提出了基于平均差异度的改进k-prototypes聚类算法.通过利用平均差异度选取初始聚类中心,避免了初始聚类中心点选取的随机性,同时利用信息熵确定数值数据的属性权重,并对分类属性度量公式进行改进,给出了一种混合属性数据度量公式.结果表明,改进后的算法具有较高的准确率,能够有效处理混合属性数据. 展开更多
关键词 k-prototypes算法 聚类 初始聚类中心 混合属性数据 平均差异度 信息熵 属性权重 度量公式
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基于Prototype的文本框自动填充功能的实现
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作者 张玉叶 《计算机时代》 2013年第6期53-55,57,共4页
以医院管理系统医生开具药方模块中文本框自动填充功能的实现为例,详细介绍了如何利用Prototype框架和基于文本的数据交换格式JSON实现文本框的自动填充功能,介绍了Prototype框架中实现AJAX的异步通信时用到的关键技术,给出了具体实现... 以医院管理系统医生开具药方模块中文本框自动填充功能的实现为例,详细介绍了如何利用Prototype框架和基于文本的数据交换格式JSON实现文本框的自动填充功能,介绍了Prototype框架中实现AJAX的异步通信时用到的关键技术,给出了具体实现过程及主要代码。实践证明,基于AJAX的异步请求原理实现的文本框的自动填充功能,不但方便了医护人员的使用,也大大提高了其工作效率,减少了病人的等待时间。 展开更多
关键词 AJAX prototype JSON 自动填充
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