1、附录 1 外文原文 COLOR SYSTEM OVERVIEW In the age of office automation and electronic imaging, office documents are being processed, transported, and displayed in a variety of ways. The scope of document processing is enormous; it encompasses page layout, document length, collation, simplex/duplex, color,
2、image quality, finishing, and binding. If the office system is networked, then another dimension of network-related issues-protocol, file format, page description language, compression/decompression, job management, error handling, user interface, and device driver-has to be addressed. Digital color
3、-imaging systems process electronic information from various sources; images may come from a local-area network, a remote-sensing device, different color workstations, or a local scanner. After processing, a document is usually compressed and transmitted to several places via a computer network for
4、viewing, editing, or printing. Moreover, the trend in the industry is moving toward an open environment. This means that various devices such as scanners, computers, workstations, modems, and printers from multiple vendors are assembled into one system. Implementations should be based on public-doma
5、in technology rather than proprietary standards. This will allow vendors equal access to the market for system components and give users the widest choice in selecting components. It is a vastly large task to enable the communication of all system components regardless of differences in the operatin
6、g system, file format, page description language, and information content. Ideally, the exchange should not cause information loss or alteration. A closer look at a document may reveal that it consists of different types of images, primarily text, graphs, and pictorial images. These all have differe
7、nt image characteristics and representations such as ASCII (American Standard Code for Information Interchange) for text, vector for graphs, and raster for pictorial images. Each type of image and its associated attributes like the font, font size, halftone, gray level, resolution, and color have to
8、 be dealt with differently. In such a complex environment, there is no doubt that many compatibility problems occur when an image is acquired, transmitted, displayed, and rendered. ? With the fast development of Internet technology, large volumes of data in the form of electronic documents from the
9、Web. For the purposes of data integration and data exchange, more and more existing sources, such as relational databases, support public XML export, and increasing amount of public and private data is described in a semi-structured way. A number of issues need to be addressed when we integrate data
10、 from different sources, including heterogeneous and duplicate data, multiple divisions and partners, and changes. ? Data heterogeneity results from the use of different information management systems to store data and each system has its own data structure and access methods. Relational database ma
11、nagement systems benefit from the universal acceptance of Structured Query Language (SQL) as the primary means of getting answers whilst document and email repositories are generally accessed using text search engines with varying interfaces and capabilities. Because these systems were not designed
12、with interoperability in mind, each must generally be accessed using source-specific applications or application programming interfaces (APIs). ? Another difficulty in data integration is data duplication-different systems represent the same piece of data in different ways. For example, customers ma
13、y be identified by name in one database, but by account number in a second repository, may identify the same customer by email address. Frequently a required piece of information is derived from multiple data points. Data integration is further complicated when customers do business with multiple di
14、visions within a large company, or with other partners. Similarly, answering questions about the state of a companys supply chain requires access to vendor and distributor information sources. Doing business electronically across the firewall gives rise to security and data ownership issues. Finally
15、, data integration has to deal with different types of changes; change in business requirements and strategies, in IT systems, mergers and acquisitions, and new product launches. This demands that a data integration solution be sufficiently flexible and adaptable. One possible solution for the data
16、integration problems mentioned above is to provide an XML Web services break down the barriers between different computing platforms, development environments and communications networks, allowing organizations to work together electronically without the expense and delay of agreeing on semantics, s
17、chema, interfaces, and other application integration. XML provides the flexibility for handling data with differing structures. As XML is becoming the principal medium for data exchange over the Web and for information integration in general, increasing amounts of public and private data are describ
18、ed in XML. XML data is usually defined in a tree or graph based, self-describing object instance model (Boncz and Kersten, 1999). However, semi-structured data is incompatible with the flat structure of relational database tables, and so the growth of XML data requires new and complex query optimiza
19、tion techniques. Creating XML files with a text editor would be a lot easier if you didnt have to close all those HTML tags. First you have to add the XML declaration and the root opening and closing HTML tags. Next, you start adding element opening and closing tags one at a time. Of course, once yo
20、u have the initial sequence completed you can just copy and paste to repeat the required elements. After doing this hundreds of times youll be looking for a faster way to create XML files. Some XML editors will automatically add the closing tag after you have finished typing the opening tag but, you
21、 still have to type the brackets around the opening tag. I kept thinking this process should be easier. So, I came up with a solution that allows you to create XML files without using HTML tags. This console application will create an XML file based on user input. Just enter the file name, how many
22、element fields you want, and the name of each field. Optionally, you can include a data type separated by a comma after the field name. You can just enter the field name because the data type is not required. The structure of the XML file that is created will be compatible with the .NET Dataset and
23、can be easily added to a database. In addition to creating the XML file, an XSL file and HTML file are also created. The HTML file uses client side JavaScript to transform the XML file using the XSL file. This provides an easy way to view the new XML file by displaying it in a table layout. The down
24、load includes both the source code and the already compiled application. You can start using the executable right away or customize it to meet your needs. All you will need is the .NET Framework and a text editor, like Notepad, to build this application. Improving ASP Performance with Data Caching One of the nicest features of ASP.NET is the ability to cache page content. This can be used to substantially reduce load on a websites database - which is an obvious attraction if the site uses Microsofts Access to store data rather than SQL Server. Unfortunately there is no built in caching