Safe drinking water and good environmental sanitation are the necessary conditions for the healthy survival of human beings. With the development of our country, the problems of water supply and drainage become more and more important. 

Water supply and drainage engineering is the combination of all engineering facilities from water source to final disposal in cities or industrial enterprises. It is generally composed of water intake project, water purification project, sewage treatment project, sludge treatment and disposal project and water supply and drainage pipe network project. According to the different historical stages of engineering construction, it can be divided into new projects and reconstruction and expansion projects.
    Its construction and development is directly related to the improvement of the living standard and quality of life of urban residents and the expansion and development of industrial enterprises, but it is limited by the local natural resources, economic development level, cultural background and development history. With the acceleration of China’s urbanization and the development of industrial economy, the demand for domestic water of urban residents and industrial enterprises is increasing, and the requirements of water quality are also increasingly strict.
    However, China is a country with very poor per capita water resources. At present, the serious water pollution makes some water bodies lose their original functions and aggravate the tension of water resources. The shortage of water resources and the pollution of water environment have become one of the key factors restricting the sustainable development of human society and economy.
    Due to the limited level of the editor, omissions are inevitable. Readers are requested to make comments and corrections.

前 言

安全的饮用水和良好的环境卫生是人类健康生存的必需条件。随着我国发展的步伐逐渐加快，给水、供水和排水的问题显得越来越重要。
      供水、给水、排水工程是城市或工业企业从水源取水到最终处置的全部工程设施的组合体。一般由取水工程、净水工程、污水处理工程、污泥处理与处置工程等主要枢纽工程和给水排水管网工程组成，按照工程建设的历史阶段不同，可分为新建工程和改扩建工程。
      它的建设与发展直接关系到城市（镇）居民的生活水平、生活质量的提高与工业企业规模的扩大与发展，但是又受到当地自然资源状况、经济发展水平、文化背景与发展历史的限制。随着我国城市化步伐的加速和工业经济的发展，城市居民生活用水和工业企业用水需求量日益增加，对用水水质的要求也日益严格。
      但是，我国是一个人均水资源十分贫乏的国家，目前严重的水污染使得部分水体丧失原有的功能，更加剧了水资源的紧张状况。水资源的日趋短缺和水环境的污染已成为制约人类社会和经济可持续发展的关键因素之一。
      由于编者水平有限，疏漏之处在所难免，敬请读者批评指正。

Forestry is the main body of ecological environment, which plays an important role and significance in economic development, ecological construction and social progress. With the continuous development and reform of China’s policies and the development of global economic integration, the development of ecological economy has gradually become an important symbol of modernization. In the face of such opportunities and challenges, forestry work shoulders a more important mission. To achieve scientific development, we must take the development of forestry as a major measure. To build ecological civilization, we must take the development of forestry as an important way. To deal with climate change, we must take the development of forestry as a strategic choice. To solve the problems of agriculture, countryside and farmers, we must take the development of forestry as an important way. Therefore, it is our responsibility to comprehensively promote the development of modern forestry and accelerate the construction of ecological civilization.
    In recent decades, China’s forestry has experienced the stage of mainly wood production, and then realized the transformation to ecological construction. Nowadays, with the deepening of the understanding of forest, we are building the forest into a comprehensive functional body of complete ecological system, developed forestry industry system and advanced forest culture system. This will promote China’s forestry to a new stage of building modern forestry.
    Due to the short time and limited level, there are inevitably some mistakes and mistakes in the book. Readers can make criticism and correction.

前 言

林业是生态环境的主体，对经济的发展、生态的建设以及推动社会进步具有重要的作用和意义。随着我国政策的不断发展和改革，以及全球经济一体化的发展，生态经济的发展逐渐成为现代化建设的重要标志，面对这种机遇和挑战，林业工作肩负了更加重大的使命，实现科学发展、必须把发展林业作为重大举措；二是建设生态文明，必须把发展林业作为重要途径；三是应对气候变化，必须把发展林业作为战略选择；四是解决“三农”问题，必须把发展林业作为重要途径。因此，全面推进现代林业发展进程，加快生态文明建设，是当今时代赋予我们的责任。
      近几十年来，我国林业经历了以木材生产为主的阶段之后，又实现了向以生态建设为主的转变。如今，随着对森林认识的深化，又正在实践着将森林建设成完备的生态体系、发达的林业产业体系和先进的森林文化体系的综合功能体。这就将我国的林业推进到了建设现代林业的新阶段。
      由于时间仓促，水平有限，书中难免有不妥与错误之处，谨祈读者批评指正。

With the development of urban construction, people pay more and more attention to the environment, especially the beautification of the environment. Garden construction has become an important part of urban beautification. Garden not only plays an important role in urban landscape, but also plays an important role in ecology and leisure. More and more attention has been paid to the construction of urban gardens. Many cities have put forward the goal of building international garden cities and ecological garden cities, strengthening the landscape planning of new urban areas and green space transformation of old urban areas, and promoting the vigorous development of landscape industry. Accordingly, the social demand for landscape professionals is also increasing, especially those who know landscape planning and design, landscape engineering construction, but also green space maintenance of high skilled talents become the landscape industry in short supply. In order to meet the needs of the construction and development of various regions and cities for landscape high skilled talents, this book is specially compiled.
    The characteristics of this book are that the content is closely combined with the actual production, the theoretical basis focuses on the content required by the practical skills, and closely coordinates with the practical training projects. At the same time, it also pays attention to the introduction and training of the rapidly developing advanced technology, which has three major characteristics of strong practicability, technicality and operability. The compilation of this book has widely absorbed the opinions and suggestions of relevant experts, teachers and landscape architects. It is based on the cultivation of landscape architecture professionals with comprehensive innovation ability. The contents are carefully selected. The comprehensive and systematic scientific system of relevant knowledge and skills is considered. The theoretical depth of the textbook is appropriate, and the combination of practical experience and achievements is emphasized.

前 言

随着城市建设的发展，人们越来越重视环境，特别是环境的美化，园林建设已成为城市美化的一个重要组成部分。园林不仅在城市的景观方面发挥着重要功能，而且在生态和休闲方面也发挥着重要功能。城市园林的建设越来越受到人们重视，许多城市提出了要建设国际花园城市和生态园林城市的目标，加强了新城区的园林规划和老城区的绿地改造，促进了园林行业的蓬勃发展。与此相应，社会对园林类专业人才的需求也日益增加，特别是那些既懂得园林规划设计、又懂得园林工程施工，还能进行绿地养护的高技能人才成为园林行业的紧俏人才。为了满足各地域市建设发展对园林高技能人才的需要，特编写本书。
      本书的特点是内容紧密结合生产实际，理论基础重点突出实际技能所需要的内容， 并与实训项目密切配合， 同时也注重对当今发展迅速的先进技术的介绍和训练，具有较强的实用性、技术性和可操作性三大特点。本书编写广泛吸收了有关专家，教师及风景园林工作者的意见和建议，立足于培养具有综合创新能力的普通本科风景园林专业人才，精心选择内容，既考虑到了相关知识和技能的科学体系的全面系统性，教材理论深度合适，注重对实践经验与成就的结合。

Today’s world has entered the information age, information has become an important strategic resource, information science has become one of the most active disciplines, information technology has changed people’s life and work style, information industry has become the leading industry of national economy. It is the basis of information transmission. Communication technology has become the fastest growing and fastest-growing industry in the information industry. At present, the rapid development of personal communication system and ultra-high speed communication network has promoted the further development of information science, and has become a powerful driving force for the international community and global economy in the 21st century. The modern communication technology of digital communication, satellite communication and sensor network has developed from wired communication to wireless communication, from communication between fixed equipment to mobile communication, from wireless communication to wireless Internet, to sensor network technology. The future communication will provide people with all-round and seamless mobile access, and ultimately realize any communication at any place and at any time, so that the communication technology can adapt to the needs of the development of society, showing a lasting momentum.
    And mechanical and electrical innovation is also progressing with the development of society. Innovation is the development of inheritance. Only when we have a deep understanding of the known objects, affirm and retain the reasonable contents, we can find the contents that can not meet the needs of the reality; if we have a certain understanding of the actual needs and have not seen the objects that can meet the needs, then innovation will have a starting point. The result corresponding to the starting point is not unique, but varies from person to person. There may be differences in principle and structure. This feature provides a wide space for innovative design. Mechanical and electrical innovation tries to combine demand problem, scientific theory, reference object and method application to show the application of mechanical and electrical innovation design.

前 言

当今世界已经进入了信息时代，信息成为一种重要的战略资源，信息科学成为最为活跃的学科领域之一，信息技术改变着人们的生活和工作方式，信息产业已经成为国民经济的主导产业，作为信息传输基础的通信技术则成为信息产业中发展最为迅速，进步最快的行业。目前，个人通信系统和超高速通信网络迅猛发展，推动了信息科学的进一步发展， 并成为 21 世纪国际社会和全球经济的强大动力。 数字通信、卫星通信以及传感器网络的现代通信技术从有线通信到无线通信，从固定设备间的通信到移动通信，从无线通信到无线因特网，到传感器网络技术不断发展。未来的通信将为人们提供全方位以及无缝的移动性接入， 最终实现任何人在任何地方、任何时间进行任何方式的通信， 使得通信技术适应社会的发展需要呈.现经久不衰的势头。
      而机电创新也不断随着社会发展而进步，创新是对继承的发展，只有对已知的对象有深刻的认识，在对合理的内容予以肯定、保留的同时发现不能满足现实需求的内容；对现实的需求有一定的了解且尚未见到能满足此需求的对象，创新才有了起点。起点对应的结果不是唯一的，而是因人而异，既可能有原理上的差异，也可能有构造上的差异，这种特性为创新设计提供了宽阔的空间。机电创新力图将需求问题、科学理论、参照对象与方法运用相结合、展示机电创新设计的应用。

From the birth of the first computer in the world to the increasing popularity of Internet today, the development speed of computer can be described as rapid progress, which also brings human civilization into the information age. The emergence of computer network makes people have a more choice in obtaining and transmitting information, and it is a choice that can provide unprecedented “liberalization”. It makes the speed, quality and scope of information spread a qualitative leap in time and space.
    With the wide application and rapid development of computer in various fields of society, the popularization speed of network is beyond people’s imagination. The information transmitted, stored and processed through the network is growing exponentially. The network has become an indispensable infrastructure in the information society. However, network security and network application security have always been the focus of people’s close attention. The openness of the network, especially the Internet network, and the existence of security threats such as system defects and loopholes, malicious attacks, computer viruses, misoperation of staff and weak security awareness, make the security of various network-based applications such as e-commerce, e-government and so on are seriously challenged. Therefore, strengthening network security management and improving network security and availability has become a major issue related to national security, economic development and social stability, and it has important strategic significance.
    With the advent of the Internet era, the “moral vacuum” appears in virtual space, which has a great impact on the traditional social life order. College students are an important part of network users. According to the survey, with the acceleration of university information process and the improvement of campus network access conditions, college student’ network behavior is becoming more and more common, and Internet access has become an important part of college students’ learning, communication, entertainment and other life. At the same time, due to the increasing number of crimes on the Internet, cyber crime has become a social and public security issue that developed countries and developing countries have to pay attention to. standardizing network behavior and preventing network crime has become one of the subjects that the whole society must face.

前 言

从世界上第一台计算机诞生到今天互联网的日益普及，计算机的发展速度可谓突飞猛进，从而也把人类文明带入信息时代。计算机网络的出现，使人们在获取和传递信息时又多了一种选择，而且是一种能够提供空前“自由化”的选择。它使信息的传播速度、质量与范围在时间和空间上有了质的飞跃。
      随着计算机在社会各个领域中的广泛应用和快速发展，网络的普及速度超出了人们的想象，通过网络传输、存储和处理的信息星几何级数增长，网络已经成为信息社会不可或缺的基础设施。但是网络安全以及网络应用安全一直以来都是人们密切关注的焦点，网络尤其是 Internet 网络的开放性加上系统的缺陷与漏洞、恶意攻击、计算机病毒、工作人员的误操作以及安全意识淡薄等安全威胁的存在，使得基于网络的各种应用如电子商务、电子政务等的安全受到了严重挑战。因此，加强网络安全管理、提高网络安全性和可用性已经成为关系国家安全、经济发展和社会稳定的一个重大课题，具有重要的战略意义。
      随着网络时代的到来，虚拟空间出现“道德真空”，对传统的社会生活秩序造成很大冲击。大学生是网络用户的重要组成部分。调查获悉，随着高校信息化进程的加快和校园内网络接入条件的改善，大学生的网络行为越来越普遍，上网成为大学生学习、 交往、娱乐等生活的重要内容。同时，由于网络上的犯罪现象越来越多，网络犯罪已成为发达国家和发展中国家不得不关注的社会公共安全问题。规范网络行为，防治网络犯罪，已成为整个社会必须面对的课题之一。