SQL自己连接

说明：  学生信息登录界面，和实现了增删改等处理功能，很实用的源代码(Student Information login screen, and realized the additions and deletions and other processing functions, very useful source code)

dataset-dimensionality-reduction-python-master

用vb编写的对文本文件的操作程序，包含文本文件的读写，切割。-With vb text file written operating procedures, including reading and writing text files, cutting.

说明：  巴西电商数据集，含九张分类表，可用于电子商务数据统计分析。(Brazilian e-commerce data set, including nine classifications, can be used for statistical analysis of e-commerce data.)

说明：  问道etc,可用于更改替换，解压后用WinSCP打开并替换etc，之后重启生效(Ask etc, which can be used to change substitution, open and replace etc with WinSCP after decompression, and then restart to take effect)

说明：  保证客人预订、退订客房准确得到回应， 保证客人入住、店内消费得到良好的管理， 保证客人换房得到良好的回应， 保证客人结算准确良好的管理， 保证客房状态及时更改以便于查询预订， 保证特殊人群的特殊服务（贵宾卡）， 保证财务结算准确高效（入账：客人结算，出账：工资发放、日常维修、水电费以及押金的管理）， 贵宾卡的发放（累计消费达到一定数目）， 关于团体入住要保证客房的合理安排。(Ensure guest's reservation and room return are accurately answered. Ensure that guests are admitted and store consumption is well managed. Ensure a good response to the guests' room change. Ensure the accurate and good management of the guests. Ensure timely change of guest room status to facilitate booking enquiries. To ensure special services for special populations (VIP cards). Ensure that the financial settlement is accurate and efficient (Accounting: customer settlement, payment: payroll, daily maintenance, water and electricity charges and deposit management). The issuance of VIP cards (cumulative consumption reached a certain number). For group occupancy, ensure reasonable arrangement of guest rooms.)

调频扩频，差分跳频技术是近年出现的一种新型扩频通信技术，他集跳频图案、信息调制与解调等功能于一体，构成与传统跳频技术完全不同的技术体制。对近年出现的扩频通信新技术——差分跳频技术进行了全面介绍。在对差分跳频关键技术进行详细分析的基础上，着重说明其优点及尚需解决的问题。 (Spread Spectrum Frequency Modulation)

本图为mf-9型万用表电路图，希望对大家有用-the map mf-9-Multimeter circuit, and we hope to useful

本篇文章叙述了锁相环原理，是学习锁相技术不可多得一篇好文章(This article describes the principle of phase-locked loop, phase-locking technology is invaluable to learn a good article)

说明：  支持向量机回归(SVR)理论是建立在支持向量机分类问题的基础上的，确Vapnik通过引入不敏感损失函数 ，将SVM分类理论中得到的结果推广，使其可以用于函数回归。(The theory of support vector machine regression (SVR) is based on the classification of support vector machines. Vapnik extends the results of SVM classification theory by introducing insensitive loss function, so that it can be used in functional regression.)