【正文】 while less powerful systems let you insert illustrations created by other programs. Initial desktop publishing solutions were expensive due to the cost of specialized puting systems and accessories, such as printers and scanners. The cost of puters and printers has fallen dramatically in recent years (., inkjet printers are amazingly inexpensive and most can print in color), allowing most personal users to acquire desktop publishing systems. Calendars and Schedulers. A calendar program enables us to record events and appointments on an electronic calendar. Calendars allow scheduling, project management, and coordination among many people, and may provide support for scheduling equipment as well. Typical features identify conflicts in schedules, find meeting times that will work for everyone, signal uping events, and automatically fill in entries for regular events. A special type of calendar, called a scheduler, is a solution to manage the daily scheduling needs of a business, such as scheduling appointments, equipment, staff (technicians, professionals, healthcare workers, others), vehicles, resources, projects, and meeting rooms. Scheduling software is an important investment for any type of business that wants to improve its scheduling processes. Every employee can have instant access to whom or what is available at any time of the day, week, month, or year and print detailed list reports. It is also possible to export schedules that may be easily opened in a word processor or spreadsheet. Paint and Draw Program. A paint program or a graphics program enables the creation of pictures, backgrounds, buttons, lines, and other creative art. Paint programs provide easy ways to draw mon shapes, such as straight lines, rectangles, circles, and ovals. Some programs also have photo editing capabilities and are optimized for working with specific kinds of images, such as photographs, but most of the smaller paint programs do not have this option. Paint programs are pixel based. They use ??raster?? images made up of small dots called pixels. As each dot is an individual, it can be difficult to move shapes around the screen. A draw program is different from a paint program. Draw programs are object based, where an object is a geometrical shape, such as a line, a circle, a curve, a rectangle, a polygon, or a Bezier curve (curves that have hooks along their length so you can alter the angle of the curve at any point.) With draw programs, images are stored as mathematical information in the form of vectors for the lines and curves of each shape. Sophisticated programs often blur the difference between draw and paint, so it is possible to find programs that are able to do both types of work. Digital Communication Systems. Nowadays, more and more puters are not isolated but, instead, are connected into a puter work that is often connected to other puter works in much the same way as telephone systems connect telephones. If a puter is connected to such a work, it is possible to municate with people whose puters are connected to the same work. Electronic Mail. Electronic mail, or for short (another mon spelling for is ), is one of the most popular uses of the Inter. It is a simple tool for exchanging brief messages between individuals or among a larger audience. Most mainframes, miniputers, and puter works have an system. An address identifies a person and the puter for purposes of exchanging electronic mail messages. It consists of two parts: user name and mail domain or domain name. The user name identifies a particular person. The mail domain identifies the place on the Inter to which the for that person should be sent. An address is read from left to right. An example is illustrated in Fig. 6. With an account, it is possible to send a message to anyone with an account. Just as a written letter can be sent to multiple recipients, an electronic mail message can be sent to one or more addresses. An can be broken down into several basic fields that include ?From?, ?To?, and ?Cc?. The ?From? field contains the address of the sender of the message. The ?To? field indicates the addresses of one or more recipients who are the primary audience. All recipients can see every address listed in this field. Finally, the ?Cc? field (Cc Carbon Copy) contains the addresses of recipients how are not the primary audience for the . Figure 6. EMail address structure An electronic mail message is not limited to text. Other types of files can be added to mail messages as attachments. Attachments can be text files or binary files such as word processed documents, spreadsheets, images, files of sound and video, and software. To see if you have any , you can check your electronic mailbox periodically, although many programs can be configured to alert users automatically when mail is received. After reading an , it may be stored, deleted, replied to, forwarded to others, or printed. 指導(dǎo)教師評語： 簽名： 年 月 日 注： 請將該封面與附件裝訂成冊。s method have been proposed by the authors and others. Some of these attempts to restrict the longest links in the work, while others reduce the number of edges from any particular node. Still other modifications introduce a simple hierarchy to the work. None of them produce convincingly realistic works. 2 A Better Method Over the past few years a better method has been devised independently by the authors for gener