检索结果-内蒙古大学图书馆

您好，读者！请登录

内蒙古大学图书馆

首页
概况
党建
资源
服务
科研支持
- 论文收录引用证明
- 科技查新
知识产权
档案馆
帮助

咨询与建议

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

您的常用邮箱：*

您的手机号码：*

问题描述：

当前已输入0个字，您还可以输入200个字

全部搜索
期刊论文
图书
学位论文
标准
纸本馆藏
外文资源发现
数据库导航
超星发现

高级检索

时间限定

出版年份：

文献类型

图书期刊文献学位论文多媒体

馆藏选择

电子馆藏纸本馆藏

核心期刊

全部期刊 SCI 收录期刊 SSCI 收录期刊 EI 收录期刊 CSCD 收录期刊 CSSCI 收录期刊

语言

中文英文

文献类型

期刊文献图书学位论文标准纸本馆藏

帮助

文字说明：

T=题名（书名、题名），A=作者（责任者），K=主题词，P=出版物名称，PU=出版社名称，O=机构（作者单位、学位授予单位、专利申请人），L=中图分类号，C=学科分类号，U=全部字段，Y=年（出版发行年、学位年度、标准发布年）

检索规则说明：

AND代表“并且”；OR代表“或者”；NOT代表“不包含”；(注意必须大写,运算符两边需空一格)

检索范例：

范例一：(K=图书馆学 OR K=情报学) AND A=范并思 AND Y=1982-2016
范例二：P=计算机应用与软件 AND (U=C++ OR U=Basic) NOT K=Visual AND Y=2011-2016

分类表

所选分类

>> <<

限定检索结果

文献类型

35,893 篇 会议
20,019 篇 期刊文献
480 册 图书

馆藏范围

56,391 篇 电子文献
2 种 纸本馆藏

日期分布

学科分类号

32,736 篇 工学
- 17,700 篇 计算机科学与技术...
- 14,006 篇 软件工程
- 8,879 篇 信息与通信工程
- 6,973 篇 电子科学与技术（可...
- 6,160 篇 电气工程
- 5,147 篇 控制科学与工程
- 3,224 篇 生物工程
- 2,927 篇 光学工程
- 2,741 篇 生物医学工程（可授...
- 2,410 篇 机械工程
- 2,189 篇 仪器科学与技术
- 2,049 篇 动力工程及工程热...
- 1,973 篇 化学工程与技术
- 1,809 篇 材料科学与工程（可...
- 1,009 篇 交通运输工程
- 901 篇 安全科学与工程
- 839 篇 建筑学
19,042 篇 理学
- 8,860 篇 数学
- 7,355 篇 物理学
- 3,685 篇 生物学
- 2,871 篇 统计学（可授理学、...
- 2,094 篇 系统科学
- 2,057 篇 化学
6,697 篇 管理学
- 4,439 篇 管理科学与工程(可...
- 2,465 篇 图书情报与档案管...
- 2,092 篇 工商管理
2,591 篇 医学
- 2,189 篇 临床医学
- 1,831 篇 基础医学(可授医学...
- 1,193 篇 药学(可授医学、理...
1,092 篇 法学
- 918 篇 社会学
794 篇 经济学
515 篇 农学
496 篇 教育学
213 篇 文学
141 篇 军事学
78 篇 艺术学
13 篇 哲学
8 篇 历史学

主题

880 篇 computer science
834 篇 computational mo...
677 篇 feature extracti...
623 篇 bandwidth
616 篇 accuracy
607 篇 optimization
571 篇 training
563 篇 wireless communi...
526 篇 machine learning
509 篇 wireless sensor ...
480 篇 computer archite...
479 篇 deep learning
471 篇 hardware
464 篇 mathematical mod...
452 篇 control systems
441 篇 neural networks
434 篇 switches
433 篇 robustness
427 篇 algorithm design...
422 篇 internet of thin...

机构

896 篇 department of el...
677 篇 department of el...
563 篇 department of ph...
512 篇 cavendish labora...
431 篇 oliver lodge lab...
406 篇 physikalisches i...
377 篇 faculty of scien...
361 篇 school of comput...
360 篇 department of ph...
355 篇 department of ph...
348 篇 school of electr...
342 篇 department for p...
314 篇 department of ph...
281 篇 department of el...
280 篇 infn sezione di ...
277 篇 department of el...
275 篇 kirchhoff-instit...
274 篇 institute of phy...
261 篇 department of ph...
261 篇 instituto de fís...

作者

324 篇 c. alexa
322 篇 j. m. izen
318 篇 g. bella
317 篇 d. calvet
317 篇 c. amelung
316 篇 j. strandberg
304 篇 g. spigo
294 篇 f. siegert
286 篇 r. ströhmer
284 篇 y. tayalati
277 篇 m. rijssenbeek
272 篇 s. jin
262 篇 g. gaudio
252 篇 m. klein
249 篇 f. pastore
248 篇 s. mohapatra
238 篇 n. orlando
205 篇 s. veneziano
203 篇 s. guindon
200 篇 a. kaczmarska

语言

53,040 篇 英文
2,524 篇 其他
756 篇 中文
51 篇 日文
23 篇 朝鲜文
7 篇 法文
6 篇 德文
4 篇 土耳其文
3 篇 阿拉伯文
2 篇 俄文
2 篇 斯洛文尼亚文
1 篇 西班牙文
1 篇 爱沙尼亚文

检索条件"机构=Department of Informatics and Computer Engineering Electronic Engineering"

共 56392 条记录，以下是4531-4540 订阅

全选清除本页清除全部题录导出标记到"检索档案"

详细简洁

排序：

Context-Aware Recognition of Elevator Buttons Using a Sequential Training Methodology

Context-Aware Recognition of Elevator Buttons Using a Sequen...

引用

International Conference on Control, Automation and Systems ( ICCAS)

作者： Arpan Ghosh Kyeong-Jin Joo Gilberto Galvis Giraldo Tae-Yong Kuc Department of Electrical and Computer Engineering Sungkyunkwan University Suwon South Korea Department of Electronic and Electrical Engineering Sungkyunkwan University Suwon South Korea

ISBN: (数字)9788993215380

ISBN: (纸本)9798331517939

In this paper, we present a sequential training methodology aimed at improving the recognition of elevator buttons using the YOLOv5 object detection model. The methodology is structured into three distinct phases. In the first phase, we generate a synthetic dataset where elevator buttons, cropped from their original context, are placed on random image backgrounds. This phase is designed to help the model learn to identify buttons independently of their surroundings, ensuring a foundational understanding of button features without contextual distractions. In the second phase, we augment the cropped button dataset by applying various transformations such as random flips, rotations, and scaling. These augmentations increase the diversity and robustness of the training data, allowing the model to generalize better to variations in button appearances. The final phase involves training the model on images of full elevator panels. This step is crucial for helping the model understand the contextual placement and spatial relationships of the buttons within the panel, which is essential for accurate detection in real-world scenarios. Additionally, we enhance the real-time video input exposure to improve visibility under varying lighting conditions, addressing common challenges faced in practical applications. For post-processing, we integrate a Channel and Spatial Reliability Tracker (CSRT) to maintain button-tracking consistency in video sequences. This tracker helps ensure that once a button is detected, its position is reliably followed across frames, improving the overall accuracy and reliability of the system. This comprehensive approach, which combines the use of synthetic data, extensive data augmentation techniques, and contextual training on full panel images, aims to better simulate real-world scenarios. As a result, the proposed methodology significantly enhances the robustness and reliability of the YOLOv5 model in recognizing elevator buttons under diverse condi

关键词： Training YOLO Accuracy Video sequences Training data Streaming media Elevators Robustness Synthetic data Context modeling

来源：评论

学校读者我要写书评

暂无评论

Learning Dual-Fused Modality-Aware Representations for RGBD Tracking 17th

Learning Dual-Fused Modality-Aware Representations for RGBD...

引用

17th European Conference on computer Vision, ECCV 2022

作者： Gao, Shang Yang, Jinyu Li, Zhe Zheng, Feng Leonardis, Aleš Song, Jingkuan Department of Computer Science and Engineering Southern University of Science and Technology Shenzhen China University of Birmingham Birmingham United Kingdom University of Electronic Science and Technology of China Chengdu China

ISBN: (纸本)9783031250842

With the development of depth sensors in recent years, RGBD object tracking has received significant attention. Compared with the traditional RGB object tracking, the addition of the depth modality can effectively solve the target and background interference. However, some existing RGBD trackers use the two modalities separately and thus some particularly useful shared information between them is ignored. On the other hand, some methods attempt to fuse the two modalities by treating them equally, resulting in the missing of modality-specific features. To tackle these limitations, we propose a novel Dual-fused Modality-aware Tracker (termed DMTracker) which aims to learn informative and discriminative representations of the target objects for robust RGBD tracking. The first fusion module focuses on extracting the shared information between modalities based on cross-modal attention. The second aims at integrating the RGB-specific and depth-specific information to enhance the fused features. By fusing both the modality-shared and modality-specific information in a modality-aware scheme, our DMTracker can learn discriminative representations in complex tracking scenes. Experiments show that our proposed tracker achieves very promising results on challenging RGBD benchmarks. Code is available at https://***/ShangGaoG/DMTracker. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

关键词： Target tracking

来源：评论

学校读者我要写书评

暂无评论

Parity symmetry of reflection, optical symmetric pushing, and pulling-pushing flipped force in parity-time symmetric photonic systems

Parity symmetry of reflection, optical symmetric pushing, an...

引用

CLEO: Science and Innovations, S and I 2022

作者： Lee, Jeng Yi Chen, Pai-Yen Department of Opto-Electronic Engineering National Dong Hwa University Hualien974301 Taiwan Department of Electrical and Computer Engineering University of Illinois at Chicago ChicagoIL60661 United States

ISBN: (数字)9781957171050

ISBN: (纸本)9781557528209

By Lorentz reciprocity theorem and parity-time (PT) symmetry, we propose a generalized parametric space for any PT symmetry photonic systems to indicate symmetry phase, broken symmetry phase, exceptional point, transmittance and reflectances. Through this generalized parametric space, We discover the emergence of symmetry reflection and optical pulling force. © Optica Publishing Group 2022, © 2022 The Author(s)

关键词： Force Scattering Bidirectional control Reflection Optical scattering Optical reflection Nonlinear optics

来源：评论

学校读者我要写书评

暂无评论

Hybrid Disinfection Robot: A Prototype

Hybrid Disinfection Robot: A Prototype

引用

2024 IEEE Region 10 Symposium, TENSYMP 2024

作者： Hassan, Md. Mehedi Amin, Al Rahman, Md. Mizanur Islam, A.K.M. Muzahidul United International University Department of Electrical and Electronic Eneineering United City Madani Avenue Badda Dhaka1212 Bangladesh United International University Department of Computer Science and Engineering United City Madani Avenue Badda Dhaka1212 Bangladesh

ISBN: (纸本)9798350364866

This paper illustrates the development of a semi-autonomous disinfection robot featuring specialized UV-C light and Spray disinfection procedures. The robot utilizes UV-C light for disinfection in the absence of individuals and switches to spray disinfection in their presence. By integrating both systems, the limitations of each method are effectively addressed. This approach minimizes the need for harmful chemicals and residual sprays, thereby reducing ventilation requirements. To safeguard the well-being of animals and humans, the robot integrates motion sensors and cameras to identify living organ-isms, adapting the disinfection process accordingly. Its versatility offers a practical solution for disinfecting various surfaces, particularly in healthcare settings where cost-effectiveness and reduced dependence on cleaning staff are critical. Experimental results demonstrate a significant reduction in bacterial levels after a ten-minute UV-C light disinfection. Furthermore, the paper details the development of a mobile application for controlling the system, encompassing the semi-autonomous capabilities, as well as the mechanical and electrical structures. This study offers a robust, scientifically grounded approach for efficient disinfection, addressing heightened cleanliness needs. For spraying, it covers a 12.5-inch area, and UV-C light that requires at least 10,600 μ W. sec/cm2 with 90% microorganism destruction in 5 seconds. © 2024 IEEE.

关键词： Microrobots

来源：评论

学校读者我要写书评

暂无评论

Data-Driven Adaptive Control for Frequency Perturbations in Power Systems with PV-SmartParks

Data-Driven Adaptive Control for Frequency Perturbations in ...

引用

Computational Intelligence for Energy, Transport and Environmental Sustainability (CIETES Companion), IEEE Symposia on

作者： Ali Arzani Ganesh K. Venayagamoorthy Holcombe Department of Electrical and Computer Engineering Real-Time Power and Intelligent Systems Laboratory Clemson University SC USA Department of Electrical Electronic and Computer Engineering University of Pretoria South Africa

ISBN: (数字)9798331519681

ISBN: (纸本)9798331519698

Seamless operation of PV plants during both transient and dynamic conditions is imperative for all stakeholders including energy control centers. Fast and dampened transient response, low steady-state error, and stability are sought for power system operation with PV plants. For PV power perturbation at point of interconnection (POI), this can be further supported by deploying auxiliary fast-acting non-synchronous generation such as SmartParks (SPs). SmartParks are parking lots with a large number of electric vehicles performing bidirectional power transfers, namely, vehicle-to-grid and grid-to-vehicle. In this study, a data-driven adaptive frequency controller (DD-AFC) was developed for SPs to compensate for frequency perturbations at PV-POI. The DD-AFC was incorporated into the controller of SPs to provide a fast response for frequency perturbations caused by PV-site power perturbations. The adaptiveness of the frequency droop comes from data-driven empirical characterization of the PV plant operation at the PV-site location using time-series data analytics. The DD-AFC supports fast-frequency control response by SPs for mitigating fast power perturbation at PV-POIs. The effectiveness of the DD-AFC was illustrated via real-time simulations of a bulk power system with a 210MW p PV plant and 100MW p of SmartParks in RTDS.

关键词： Automatic frequency control Time-frequency analysis Vehicle-to-grid Transient response Data analysis Perturbation methods Power system stability Adaptive control Transient analysis Vehicle dynamics

来源：评论

学校读者我要写书评

暂无评论

Internet of Things Based System for Health Monitoring for Distribution Transformer 4

Internet of Things Based System for Health Monitoring for Di...

引用

4th International Conference on Advancement in electronics and Communication engineering, AECE 2024

作者： Kumar, B. Arun Duggal, Angel Swastik Naim, Arshi Hussain, Mohammad Rashid Ahmed, Mohammad Nadeem Dildar, Muhammad Shahid Lovely Professional University School of Electronics and Electrical Engineering Punjab Phagwara India University Campus King Khalid University AlSamer Department of Business Management Abha Saudi Arabia King Khalid University College of Business Department of Business Informatics Saudi Arabia King Khalid University College of Computer Science Department of Computer Science Saudi Arabia

ISBN: (纸本)9798350364729

Electricity distribution from substations to residences and businesses depends on distributed transformers. However, a number of things, including overload, overheating, and outside elements like moisture and dust, can harm them. For distributed transformers to remain operational and prevent damage, health monitoring is crucial. Using sensors to assess vital variables like voltage, current, temperature, and humidity is one approach to keep an eye on the condition of distributed transformers. To find any possible issues, the data from these sensors can be gathered and analysed. If an issue is found, it can be fixed before the transformer is harmed. A system employing Node MCU and Arduino was suggested in a study for the health monitoring of distributed transformers. An open-source platform called Node MCU makes use of the ESP8266 microcontroller. Interactive projects are developed on the open-source Arduino electronics platform. The suggested system gathers data from the sensors and transmits it to an Arduino using a Node MCU. The data is subsequently transmitted from the Arduino via the internet to a cloud server. The data can be stored on the cloud server, which can also analyse it to find any potential issues. An alert can be provided to the user if a problem is found. This technology offers a simple and affordable solution to keep track of the condition of distributed transformers. It can aid in avoiding damage and ensuring the ongoing functionality of these crucial devices. © 2024 IEEE.

关键词： Distribution transformers

来源：评论

学校读者我要写书评

暂无评论

A Self-Attention Bidirectional Long Short-Term Memory for Cold Start Movie Recommendation Models 1

A Self-Attention Bidirectional Long Short-Term Memory for Co...

引用

1st IEEE International Conference on Ambient Intelligence, Knowledge informatics and Industrial electronics, AIKIIE 2023

作者： Manohar, M. Reddy, R Archana Alzubaidi, Laith H. Hameed Abdul Hussein, Abbas Buvaneswari, P.R. Department of Computer Science and Engineering Bangalore India School of Computer Science and Artificial Intelligence Sr University Warangal India The Islamic University Najaf Iraq College of Pharmacy Ahl Al Bayt University Karbala Iraq School of Electrical and Electronic Engineering Vit Bhopal University Sehhore India

ISBN: (纸本)9798350316469

Movie recommendation systems are useful tools that help users find relevant results and prevent information overload. On the other hand, the user cold-start issue has arisen because the system lacks sufficient user data. Furthermore, they are not very scalable for use in extensive real-world applications. One of the key strategies to address the sparsity and cold-start problems is to leverage other sources of information, including item or user profiles or user reviews. Processing client feedback is typically a challenging process that involves challenging the interpretation and analysis of the textual data. Thus, this research implements an efficient deep learning-based recommendation architecture. Following the acquisition of textual data from the Amazon product reviews database, stop word removal, lemmatization, and stemming techniques are applied to the data pre-processing which eliminate inconsistent and redundant data, facilitating the process of interpreting and utilising data. Then, the Term Frequency-Inverse Document Frequency (TF-IDF) method is applied to extract the feature values from the pre-processed text data. The extracted feature values are fed to the Self-Attention Bidirectional Long Short-Term Memory (SA-BiLSTM) that utilises the matrix factorization method framework's information sources. The SA-BiLSTM model obtained 95.93% of recall, 94.76% of precision, and 97.84% of accuracy on the amazon product reviews database. © 2023 IEEE.

关键词： Bidirectional Long Short-Term Memory Lemmatization Movie recommendation Self-attention Stemming Term frequency-inverse document frequency

来源：评论

学校读者我要写书评

暂无评论

Exploring Biological Features of Electroencephalography Signals for Explanation-Guided Learning

Exploring Biological Features of Electroencephalography Sign...

引用

International Conference on electronics, Information and Communications (ICEIC)

作者： Hyosung Joo Dongseok Kim Le Thi Trang Luong Do Anh Quan Jihwan Woo Department of Electrical Electronic and Computer Engineering University of Ulsan Ulsan Republic of Korea Department of Biomedical Engineering University of Ulsan Ulsan Republic of Korea

Explanation-guided learning (EGL) has gained prominence for improving both the explainability and performance of deep neural networks by integrating additional supervision signals based on the elucidation of the model. However, its applicability in analyzing electroencephalography (EEG) signals remains underexplored. This study attempted to identify and evaluate biological features for EGL-based EEG analysis using compact convolutional neural networks. The identified features included anatomical location, dipolarity, relative peak power, and event-related desynchronization of the cortical source. The feasibility of the features was evaluated with performance prediction tests, which predict model performance based on the interpreted features. All features except dipolarity possessed a significant relationship with model performance. These findings indicate the possibility of utilizing these features as biological supervision signals in future EGL-based EEG analysis.

关键词：

来源：评论

学校读者我要写书评

暂无评论

A Portable 3D-Printed Dielectric Lens Antennas for Liquid-Mixture Characterization

A Portable 3D-Printed Dielectric Lens Antennas for Liquid-Mi...

引用

2023 IEEE International Symposium on Antennas and Propagation, ISAP 2023

作者： Sangpet, Patchadaporn Thaiwirot, Wanwisa Chudpooti, Sukanya Akkaraekthalin, Prayoot Somjit, Nutapong Chudpooti, Nonchanutt Department of Electrical and Computer Engineering Faculty of Engineering King Mongkut’s University of Technology North Bangkok Bangkok Thailand Department of Industrial Physics and Medical Instrumentation Faculty of Applied Science King Mongkut’s University of Technology North Bangkok Bangkok Thailand School of Electronic and Electrical Engineering University of Leeds Leeds United Kingdom

ISBN: (纸本)9798350341140

The Fused Deposition Modeling (FDM) method is utilized in this research to present dielectric lens antennas that were 3D printed. The ultra-wideband (UWB) stub antenna's antenna characteristic is intended to be improved by the 3D-printed dielectric lens antennas. The proportion of ethanol in the liquid mixture sample is categorized using the transmission-line measuring technique. The device-under-test (DUT) is placed between two 3D-printed dielectric lens antennas. The glass bottle is filled with a 100-ml liquid sample and covered with a plastic cap. The 3D EM Simulation CST Studio is used to optimize the 10 mm gap between the dielectric lens antennas and the DUT. Six concentrations of the ethanol/water mixture, such as empty, 60%, 65%, 70%, and 80%, are measured to examine the measurement system. The measurement outcomes indicate the various S21 (transmission coefficient) levels between 9 GHz and 11 GHz. According to the trend of the suggested system, the level of the transmission coefficient, S21, will change downward when the proportion of ethanol is increased. Several better advantages, such as a nondestructive method, non-contact measurement, and support with a real-time monitoring system, are provided by the transmission-line measuring methodology using 3D-printed dielectric lens antennas. © 2023 IEEE.

关键词： 3D-printed dielectric lens antennas Fused Deposition Modeling technique non-destructive measurement real-time monitoring system

来源：评论

学校读者我要写书评

暂无评论

Detection of DDoS Attack: A Comparative Evaluation of Machine Learning Techniques

Detection of DDoS Attack: A Comparative Evaluation of Machin...

引用

IEEE International Conference on Signal Processing, Information, Communication & Systems (SPICSCON)

作者： Afsana Mimi Iffath Tanjim Moon Md. Musfiqur Rahman Mridha Md. Shakiul Jafor Department of Computer Science & Engineering Pundra University of Science & Technology Bogura Bangladesh Department of Computer Science & Engineering Varendra University Rajshahi Bangladesh Department of Electrical and Electronic Engineering Pundra University of Science & Technology Bogura Bangladesh

ISBN: (数字)9798331510213

ISBN: (纸本)9798331510220

Distributed denial-of-service (DDoS) attacks are a common and increasing threat to online services, targeting multiple layers of the OSI model. As communication technology advances, these attacks are getting more frequent and complicated, making detection and protection more challenging. Therefore, the need to study DDoS attack detection is growing. This paper evaluated multiple machine learning models for detecting DDoS attacks using binary classifications. We have used nine machine learning models for binary classification namely Support Vector Machine, Random Forest, Gaussian Naïve Bayes, Extra Trees, AdaBoost, XGBoost, Gradient Boosting, Logistic Regression, and Multilayer Perceptron. Besides, we have selected the KDDCup99 dataset for this research. The dimensions of data determine a detection system's usefulness, consequently, feature selection and preprocessing are used to reduce the dataset's dimensionality, which minimizes the mathematical complexity. The evaluation of models is based on the accuracy, recall, precision, f1-score, false alarm rate, false positive ratio, false negative ratio, and error rate of datasets. Finally, using these evaluation criteria, we have compared the performance of the machine learning models and achieved the best results in binary classification using the XGBoost model with the highest accuracy (99.98%), precision (99.97%), recall (99.96%), f1-score (99.97%), and lowest false alarm rate (0.01 %), error rate (0.02 % ), false positive ratio (0.03 %), and false negative ratio (0.03 %).

关键词： Support vector machines Accuracy Error analysis Open systems Signal processing Denial-of-service attack Feature extraction Mathematical models Protection Random forests

来源：评论

学校读者我要写书评

暂无评论

没有更多数据了...

全选清除本页清除全部题录导出标记到“检索档案”

共500页 << < 450 451 452 453 454 455 456 457 458 459 > >>

检索报告对象比较合并检索0

隐藏清空

合并搜索

回到顶部

执行限定条件

内容：

评分：

请选择保存的检索档案：

请选择收藏分类：

订阅名称：

通借通还

温馨提示：

图书名称：

借书校区：

取书校区：

手机号码：

邮箱地址：

一卡通帐号：

电话和邮箱必须正确填写，我们会与您联系确认。

联系人：

所在院系：

联系邮箱：

联系电话：

内蒙古自治区呼和浩特市赛罕区大学西街235号邮编: 010021

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：