Nepomuk/zh-tw

Nepomuk

這個頁面的目的不是詳細解釋Nepomuk技術及其每個細節，而是作簡短的概述，舉一些例子，分享其背後的設想和給予指向網上相關資訊的鏈接。

簡短說明

如術語提到的，Nepomuk有關數據的分類，組織和表達。它並非是一個應用程序，而是可以被開發人員應用在程序中的組件。

試用

舉例來說，Dolphin採用了 Nepomuk。對於後面例舉的必須保證系統設置-> 桌面搜索 的 Nepomuk 和 Strigi 都已經開啟。 Dolphin的信息側面板允許你給文件打上標籤，評分和評論。這些信息隨後存儲在 Nepomuk 並且被 Strigi 編入索引。然後你可以在 Dolphin 裡用導航欄搜索元數據（metadata）。輸入"nepomuksearch:/"，隨後是搜索詞。

功能

Nepomuk 提供數'層'功能給應用程序。第一個也是其中最簡單的是手動標記（manual tagging），評分（rating）和註釋（commenting），如使用在Dolphin中。這有助於你更快的找到你的文件，但這種做法太耗費精力。

為了使得搜索包含文本的文件更容易，Nepomuk 提供了第二個功能：索引（indexing）文件中的文本。它使用一種被稱作Strigi 的技術來實現。現在你也能通過輸入你所已知的其中某些詞語，或僅僅（部分）它們的標題來搜索到文件。

第三層非常複雜，是Nepomuk 被視為歐盟（European union）多個公司和大學研究項目的原因。這部分你會遇到很難理解的詞組像是'語義桌面（semantic desktop）'和'本體論（ontologies）'。基本上，它涉及到語境（context）和關係（relationships)。

例子

Let me try to explain what Nepomuk offers using two examples.

Relationship

Say you received a photo from a friend of yours, 2 weeks ago. You saved it somewhere on your computer. Now how to you find that file? If you don't remember the location, you're out of luck.

Now Nepomuk aims to help you. You know this file came from that friend of yours, your computer does not. Nepomuk, however, can remember this relationship. Searching on the name of your friend will therefor pop up the photo!

Another potential relationship is between a web page you copied text from and the document you pasted it into, or two images showing the same car. Such relations can sometimes be extracted from the files themselves (you could analyze photos and see who or what is on there) or supplied by the applications involved (as in the above email example). This part of Nepomuk is still under heavy development, and needs integration in applications, so you can expect it to take a few more years to really shine.

All in all, this part of Nepomuk is about making search smart. Think about how Google tries to be smart with your searches: when you search for a hotel and a city name, it shows above the website results a google map showing hotels in the city you mentioned! It might even suggest a better name in case you made a spelling mistake. Google also tries to put the most relevant information on top of the list of results, using complex calculations on relationships (links) between websites. Nepomuk will be able to offer such smart results and order them on relevancy using relationship information.

Context

These relationships can not only help you while searching for files, but also have an influence on applications and what information they present. Note that this way of using Nepomuk is still more a vision than reality! Many of the components are in place, but it is not yet integrated in applications and the desktop as a whole.

So here an example of bringing context awareness to your desktop could help you work more efficiently.

Say you are working on finishing some notes you took in a meeting. The phone rings, and somebody asks you to find that spreadsheet with prices, adjust it for a customer. After a few more interruptions you find your desktop full of files and windows...

It'd be nice to be able to organize all that a bit better, right?

Enter 'activities'. These have been introduced in Plasma, and currently offer different 'desktops'. They are a bit like virtual desktops, except that the desktop itself changes, not the set of applications. Different widgets, background, things like that. Of course, since KDE 4.3, each virtual desktop can have it's own activity, bringing the two in sync.

If applications and desktop were aware of activities, you could create an activity for each of the tasks you regularly work on. So if you often have to change a spreadsheet with prices, you create an activity for that: put a Folder View (or several) widget on the desktop, add a calculator and a todo-widget to keep track of what you still have to change. Maybe even an email folder widget showing the mails with questions regarding these prices spreadsheets!

As soon as somebody asks a question about prices, you switch to this activity. Fire up your spreadsheet application. It is aware of your activity so it shows recent price spreadsheets, not the recent list of inventory you were working on in another activity! Kopete, the chat application shows your colleague who knows all about prices, as she is the person you always chat with when working on this activity.

When you are finished, you go back to another activity, and once again all applications adjust their behavior to fit what you are doing.

The benefits of such an activity-based work flow go further than you might at first expect. It not only helps you find files and contact persons, but also helps in switching tasks itself. The human brain isn't very good at multi-tasking - it takes most people several minutes to get up to speed after switching tasks. Changing the 'environment' helps a lot in speeding this up, even if it's just on the screen. Compare it with getting in the mood for your holiday by packing your bag!

Of course, the above is mostly relevant to people working behind their computer in the office or at home. A gamer or a casual user would probably not use these activities much.

Note that the scenario described above is still years away from reality. Much of the basic infrastructure for this in KDE is in place but much is still left.

Sharing and privacy

There is one thing I need to touch on before pointing to other sources of information: sharing Nepomuk data. It'd be great if your tags, ratings and comments would be shared with others when you send them files. However, if you tagged a contact with a slightly embarrassing tag ('boring in bed') and send that persons contact information to a mutual friend you probably don't want that tag to be send as well... This issue is of course being considered and an important subject of research by the Nepomuk researchers. For the time being, these privacy concerns, combined with technical challenges, are the reason Nepomuk context is private. Rest assured the Nepomuk team does all it can to make sure your privacy is respected.

More info:

Wikipedia - Semantic Desktop

Wikipedia - NEPOMUK Framework

NEPOMUK website

NEPOMUK KDE site

article explaining Nepomuk on the DOT