We analyze the social network emerging from the user comment activity on the website Slashdot.
Using Kolmogorov-Smirnov statistical tests, we show that the degree distributions are better explained by log-normal instead of power-law distri- butions.
We also study the structure of discussion threads using an intuitive radial tree representation.
Threads show strong heterogeneity and self-similarity throughout the dif- ferent nesting levels of a conversation.
We use these results to propose a simple measure to evaluate the degree of con- troversy provoked by a post.
To improve the quality and the representativity of the resulting graph, we filter some of the comments according to the following four criteria:
1.The post: Under this assumption, no relations exist between the post’s author and its direct commentators, unless he also participates later in the discussion.
2.Anonymous comments were also discarded.
3.We discard very low quality comments with score −1.
4.Finally, we filter out self-replies, often motivated by a forgotten aspect or error fix of the original comment.
The size of the big cluster for strongly connected components is of course, smaller.
gesting that the small-world property is present in all of them.
The quantities are approximately one unit lower than the corresponding value for a random graph ℓrand.
The maximal distance D between two users is also very small.
Even for the undirected sparse case, it only takes a maximum of eleven steps to reach a user starting randomly from any other.
These results are also in accordance with similar studies of other traditional social networks.
To study the statistical level of cohesiveness we calculate the clustering coefficient C according to [23], and also its weighted version Cw [1].
We notice no significant differences between them.
Thus the number of messages interchanged between two users is not relevant to determine the clustering level.
The impact of having a weighted network is analyzed in more detail in Section 2.5.
we associate to each user a score, which is calculated by averaging over all the scores of the comments of the same user.
This quantity allows us to differentiate high-quality writers (those with high mean score) from regular-quality writers.
The initial score of a comment is generally 1 if it comes from a registered user or 0 if it is anonymous3.
Moderation can modify the initial score to any integer within the range [−1, 5].
To ensure a representative subset of the network, we only consider users who wrote at least 10 comments, a total of 18, 476 users, representing approximately 23%.
Note that the minimum score is 0, since we eliminate −1 comments.
The distribution shows an unexpected bimodal profile, with two peaks at mean scores 1.1 and 2.3.
We take a simple approach based on agglomerative clustering which takes benefit from the weighted nature of the Slashdot network [18].
We choose the dense undirected network and start our procedure with each node as an independent cluster.
Let λ denote the number of comments, so that pairs of users (i, j) who interchange a number of comments wij ≥ λ are included in the network, and the other connections are discarded.
Starting from the biggest value λ = λmax and progressively decreasing it, users are connected incrementally and communities can be obtained.
This simple procedure is equivalent to building a dendrogram and allows to browse through the community structure at different scales by changing the parameter λ.
The vast majority of pairs of users only exchanges a small number of comments whereas a few of them really maintain intense dialogues during the year.
This seems to be the reason why previous properties such as the clustering coefficient do not show significant differences between the weighted and the unweighted network.
The most discussing pair of users exchanged a total of 108 comments.
We can see that the biggest component grows very fast and the second biggest remains small, showing evidence of a giant cluster present in all scales.
An initial picture of the activity generated by posts can be found in previous studies [12].
Posts receive on average approximately 195 comments and there exists a clear scale in the number of comments a post can originate.
Half of them receive less than 160 contributions.
A small number of highly discussed ones, however, can trigger more than one thousand contributions.
The number of comments gives an idea of how the participation is distributed among the different articles, but is not enough to quantify the degree of interaction.
For instance, a post may incite many readers to comment, but if the author of a comment does not reply the responses to his comment, there is no reciprocal communication within the thread.
In this case, although users can participate significantly, we can hardly interpret that the post has been highly discussed.
On the other hand, a post with a small number of contributors but with one long dialogue chain will evidence a high degree of reciprocal interaction (albeit its general interest may be reduced).
For deeper nesting levels, comments can be fully shown (score 4 or above), abbreviated (score between 1 and 4) or hidden (score below 1).
We propose a natural representation of thread discussions which takes advantage of their structure.
Consider a post as a central node.
Direct replies to this post are attached in a first nesting level and subsequent comments at increasing nesting levels in a way that the whole thread can be considered as a circular structure which grows radially from a central root during its lifetime, a radial tree.
Figure 7 shows three snapshots of a radial tree associated to a controversial post which attracted a lot of users.
An analog example of a less discussed post can be seen in Figure 8.
More examples of trees are shown in Figure 9.
Their profiles are highly heterogeneous.
In some examples, only a huge number of contributions without replies appear in the first level, resulting in trees with high widths but small depths.
In other examples, however, there are only discussions between two users who comment alternatively giving rise to very deep trees with small widths.
Sometimes, the intensity of the discussion is translated to one of the branches because of a controversial comment which triggers even more reactions than the original post (e.g the post in the center of Figure 9).
Apart from being a useful tool for browsing and examining the contents of a highly discussed post, radial trees can be used to describe statistically how information is structured in a thread.
In Figure 10a we plot the distribution of all the extracted comments per nesting level for all posts.
This gives an idea about the relation between the width versus the depth of the trees.
The first two levels contain most of the comments and then their number decays exponentially in function of the depth.
The maximum depth was 17.
It is important to note that a definition of controversial is necessarily subjective.
However, indicators such as the number of comments received or the maximum depth of the discussions can be, among others, good candidate quantities to evaluate the controversy of a post, but suffer from some drawbacks as we will explain in what follows.
We therefore seek for a measure, as simple as possible which incorporates as many of these factors and is able to rank a set of posts properly.
The number of comments alone does not tell us much about the structure of the discussion.
There might be a lot of comments in the first level but very little real discussions, such as in the post of Figure 12a.
A better measure for the controversy of a post seems to be the maximum depth of the nesting.
But again that measure has some drawbacks.
Two users may become entangled in some discussion without participation of the rest of the community, increasing the depth of the thread.
Unlike the BBS network [24, 8] where discussions are unrestricted, the scoring system of Slashdot guarantees a high quality and representativity of the social interaction.
This particular feature allowed us to find a correlation between scores and number of received replies and to distinguish clearly between two classes of users: good writers who, on average achieve high scores for their comments, and regular writers.
The number of replies of a comment depends mostly on its quality (the score it achieved) but we find some weak evidence for user reputation influencing the connectivity in the network.
Good writers are more likely than regular ones to receive replies to occasional comments with low scores.
However, this effect is not strong enough to cause assortative mixing by score since the opposite is not true.
Regular writers can expect a similar number of replies as good writers to their comments with high scores, so there is no negative effect of a user’s reputation.
Comments:
1. I think the author should be able to take the results compare with some of the practices in the community and do some combination, maybe can help us gain a better understanding of the meaning behind these phenomena.
2. Perhaps the author can do more explanation about the findings, this can also stimulate the feeling of the reader to the information.
2008年6月20日 星期五
2008年4月5日 星期六
Homework 3-29-2008
1. Read the abstract of Paper 3, 6 and 7. If possible, skim the whole paper. Summarize the papers briefly.
Paper 3, Paper 6 and Paper 7
2. According to Chap. 6 of Textbook. what is a functional architecture of e-commerce systems?
The way it decomposes the system into functional units. ex: Customer Data, Order Data, Payment Data, Catalog Database...
3. Lab: PageRank
PageRank is a tool for measuring the importance of websites. Given every URL, there is a PageRank value for it.
PageRank (9/10) New York Times http://www.nytimes.com
PageRank (9/10) CNN http://www.cnn.com/
Paper 3, Paper 6 and Paper 7
2. According to Chap. 6 of Textbook. what is a functional architecture of e-commerce systems?
The way it decomposes the system into functional units. ex: Customer Data, Order Data, Payment Data, Catalog Database...
3. Lab: PageRank
PageRank is a tool for measuring the importance of websites. Given every URL, there is a PageRank value for it.
PageRank (9/10) New York Times http://www.nytimes.com
PageRank (9/10) CNN http://www.cnn.com/
2008年3月28日 星期五
Homework 3-15-2008
1. Read Paper 1 & Paper 2. Provide a summary for each of the paper.
Paper 1 & Paper 2
2. Read Chap. 4 of the textbook. What is the Business-to-business model?
A Business offer the catalogs for maintenance, repair, and operations (MRO) goods and for component sourcing for products to another Business for commerce
This commerce are characterized by high-volume, low-value purchases, repeat business from the same customers, and high order processing costs for both buyers and sellers
Putting a business-to-business catalog online are immediate cost savings and an ability to provide better service
3. Digital goods can be distributed over the Internet but physical goods have to be delivered logistically. What are digital goods? What are the differences between the two?
Digital goods : some things or some services can display through computer
catch sight, touch; survive time, re-get; copy; set price...
4. Using RSS to track many blogs at one time.
done
Paper 1 & Paper 2
2. Read Chap. 4 of the textbook. What is the Business-to-business model?
A Business offer the catalogs for maintenance, repair, and operations (MRO) goods and for component sourcing for products to another Business for commerce
This commerce are characterized by high-volume, low-value purchases, repeat business from the same customers, and high order processing costs for both buyers and sellers
Putting a business-to-business catalog online are immediate cost savings and an ability to provide better service
3. Digital goods can be distributed over the Internet but physical goods have to be delivered logistically. What are digital goods? What are the differences between the two?
Digital goods : some things or some services can display through computer
catch sight, touch; survive time, re-get; copy; set price...
4. Using RSS to track many blogs at one time.
done
2008年3月14日 星期五
Homework 3-8-2008
1. Track your comments at a focal point
Done
2. Using personal portal.
3. Make your blog organized by adding labels
Done
4. Reading Assignments: Read Chap 3. Answer the following questions.
* What are the commercial values of Internet?
Transform Customer Relationships
Supplier-Centered ----------------------------Customer-Centered
Supplier chooses hours of operation ------Supplier always available, customer chooses hours
Supplier chooses locations of service -----Service delivered at customer location
Supplier delivers services -------------------Customer serves himself
Focus on supply chain -----------------------Focus on customer needs
One-to-many ----------------------------------One-to-one
Displace the Sources of Value
Physical World --------------------------------Information World
Atoms ------------------------------------------Bits
Physical value ---------------------------------Digital value
Economies of scale ---------------------------Economies of scope
Mass-produced -------------------------------Mass-customized
Information value ----------------------------Knowledge value
Distribution as a constraint -----------------Distribution as an enabler
Local --------------------------------------------Global
* List some business strategies for online commerce.
Channel Master --ex: Cisco Systems
Customer Magnet --ex: Yahoo
Value Chain Pirate --ex: Autoweb
Digital Distributor --ex: Monster.com
Done
2. Using personal portal.
3. Make your blog organized by adding labels
Done
4. Reading Assignments: Read Chap 3. Answer the following questions.
* What are the commercial values of Internet?
Transform Customer Relationships
Supplier-Centered ----------------------------Customer-Centered
Supplier chooses hours of operation ------Supplier always available, customer chooses hours
Supplier chooses locations of service -----Service delivered at customer location
Supplier delivers services -------------------Customer serves himself
Focus on supply chain -----------------------Focus on customer needs
One-to-many ----------------------------------One-to-one
Displace the Sources of Value
Physical World --------------------------------Information World
Atoms ------------------------------------------Bits
Physical value ---------------------------------Digital value
Economies of scale ---------------------------Economies of scope
Mass-produced -------------------------------Mass-customized
Information value ----------------------------Knowledge value
Distribution as a constraint -----------------Distribution as an enabler
Local --------------------------------------------Global
* List some business strategies for online commerce.
Channel Master --ex: Cisco Systems
Customer Magnet --ex: Yahoo
Value Chain Pirate --ex: Autoweb
Digital Distributor --ex: Monster.com
2008年3月7日 星期五
Homework 3-01-2008
1. According to the book by Treese and Stewart, what is the commerce value chain? Why not see them on an individual basis?
From the book, the commerce value chain gives us a useful way to think about Internet commerce projects. The commerce value chain - the following four steps link up.
1. Attract customers.
2. Interact with customers.
3. Act on customer instruction.
4. React to customer requests.
For textbook's example, we can look at the value chain of a retail store, which includes selecting products that will be sold, purchasing them from a wholesaler or manufacturer, arranging attractive displays, advertising to attract customers, assisting customers with their selections, taking payments for the products, and delivering the products to customers. Each of these links in the chain is important to the business, and if any one of them breaks down, the entire business is affected.
combined efforts, and individual basis can't satisfy : Quality：no discount, Service：Fast and Accurate, Value：to be worthy of
2. Is the Internet different from other media? Why?
I think the answer can be Yes and also can be No. The Internet link most kinds of media, and it can be presented one or multiple media. Besides, the Internet have some media differ from the old media, like BBS or Blog.
3. On this Internet-based tool, you are able to edit a paragraph while someone is working on another. In order to do so, you got to have an account to login Google. Please use your email to apply for one so that you can use it now. A link to the document will be included in the message, please just click on the link to collaborate.
Please be noted that not only can you browse the document but also you can edit and update it freely. You may see other colleagues online at the same time and refrain from making updates. Please feel free to go ahead. The software will resolve change conflicts for you.
The revision history will keep a log of all changes. So your changes will be noticed by other colleagues and re-reviewed.
Convert one of your Word document using Google docs.
4. Customize your blogs.
did it
2008年2月29日 星期五
1. List the companies Google acquired year by year.Briefly describe the strategic implications of each acquisition.
2001 Google Acquisitions
1. 2001-02-12 - Usenet Discussion Service and Significant Assets from Deja.com - Google Groups
2. 2001-09-20 - Technology Assets of Outride Inc - Online Information Retrieval Technologies
2003 Google Acquisitions
1. 2003-02-00 - Pyra Labs - Blogger
2. 2003-04-00 - Neotonic Software - Technology for Email Customer Support (CRM)
3. 2003-04-23 - Applied Semantics - Advertising Technology企業在線營銷管理工具
4. 2003-09-30 - Kaltix Corp - Personalized and Context Sensitive Search Engine Technology
5. 2003-10-07 - Genius Labs - Blogging
2004 Google Acquisitions
1. 2004-05-10 - Ignite Logic - Web Templates for Law Firms and Small Businesses ; Website creation technology
2. 2004-06-23 - 2.6% Stake in Baidu.com; 2006-06-24 ; Google Sells 2.6% Stake in Baidu.com - Chinese Language Search Engine
3. 2004-07-13 - Picasa - Digital Photo Management ; Photo management software
4. 2004-10-00 - Where 2 Technologies - Digital Mapping (Google Maps)
5. 2004-10-27 - Keyhole Corp - Digital Mapping (Google Earth)
6. 2004-12-00 - ZipDash - Maps and Traffic for Mobile Devices ; Used in Google Ride Finder
2005 Google Acquisitions
1. 2005-01-00 - 2Web Technologies - Google Spreadsheets ; Web-based spreadsheet
2. 2005-01-00 - Phatbits - Widget engine.
3. 2005-03-28 - Urchin Software - Web Analytics Software流量分析
4. 2005-05-12 - Dodgeball - Mobile Social Networking
5. 2005-07-00 - Reqwireless Inc - Java ME Browser ; Web browser and Mobile email
6. 2005-07-07 - Current Communications Group - Broadband Internet (BPL - Broadband over Power Line)
7. 2005-08-17 - Android(mobile phone platform) - Software for Mobile Phones ; Software for Handheld devices
8. 2005-09-15 - Transformic Inc - Search Engines for the Deep Web
9. 2005-11-00 - Skia - Graphics Software Engineering
10. 2005-11-17 - Akwan Information Technologies - Latin American Operations Center (Brazil, Mexico, Latin America) ; Latin American internet operations
11. 2005-12-xx - allPAY GmbH, bruNET GmbH - Mobile Solution Provider, Germany
12. 2005-12-20 - 5.0% Stake in AOL - Internet
2006 Google Acquisitions
1. 2006-01-17 - dMarc Broadcasting - Digital Solutions for Radio Broadcasting Industry ; Radio advertising software and platform.
2. 2006-02-14 - Measure Map - Web Analytics for Blogs
3. 2006-03-09 - Upstartle (Writely) - Web Based Collaborative Document Editor (Online Word Processing)
4. 2006-03-14 - @Last Software - SketchUp 3D Modeling
5. 2006-04-09 - Orion - Referential Search Engine ; Advanced search method.
6. 2006-08-15 - Neven Vision - Automatic Information Extraction from Photos
7. 2006-10-31 - JotSpot Inc - Wiki Technology for Collaborative Websites ; Website applications
8. 2006-11-13 - YouTube Inc - Consumer Media Company (Watch and Share Videos) ; Video sharing (San Bruno, CA)
9. 2006-12-00 - Endoxon - Geo Mapping Software ; Mapping solutions
2007 Google Acquisitions
1. 2007-01-00 - Xunlei (Partial Acquisition) - File Sharing Website ; Network, file-sharing
2. 2007-03-16 - Adscape Media - In-Game Advertising for Video Games ; Video game advertising
3. 2007-03-16 - Trendalyzer - Presentation Software
4. 2007-04-13 - Doubleclick - Advertising Technology Platform
5. 2007-04-17 - Tonic Systems - Presentation Creation and Document Conversion Technology
6. 2007-04-19 - Marratech - Video Conferencing Software ; Video conferencing (Stockholm, Sweden)
7. 2007-05-11 - Green Border Technologies - Secure Connections for Web Browsing and Email ; Desktop enterprise security
8. 2007-05-30~06-01 - Panoramio - Community Photos Website (Works with Google Earth) ; Geospatial Photo-sharing Service
9. 2007-06-01~03 - Feedburner - Feed Distribution and Management Tools ; RSS Feeds (Chicago, IL)
10. 2007-06-05 - PeakStream Inc - Multiprocessor and GPU Software ; Parallel Processing
11. 2007-06-19 - Zenter - Online Slide Presentations
12. 2007-07-02 - GrandCentral Communications - Services for Managing Voice Communications ; VOIP Phone Aggregation (Fremont, CA)
13. 2007-07-xx - ImageAmerica - High resolution aerial cameras
14. 2007-07-09 - Google to Acquire Postini - Services for Message Security, Archiving, Encryption, and Policy Enforcement ; Communications Security (San Carlos, CA)
15. 2007-09-xx - Tusli - Google Blogger Api Engineering Team
16. 2007-09-xx - Zingku - Mobile social network and communication platform
17. 2007-10-xx - Jaiku - An activity stream and presence sharing service that works from the Web and mobile phones (Helsinki)
1. 2001-02-12 - Usenet Discussion Service and Significant Assets from Deja.com - Google Groups
2. 2001-09-20 - Technology Assets of Outride Inc - Online Information Retrieval Technologies
2003 Google Acquisitions
1. 2003-02-00 - Pyra Labs - Blogger
2. 2003-04-00 - Neotonic Software - Technology for Email Customer Support (CRM)
3. 2003-04-23 - Applied Semantics - Advertising Technology企業在線營銷管理工具
4. 2003-09-30 - Kaltix Corp - Personalized and Context Sensitive Search Engine Technology
5. 2003-10-07 - Genius Labs - Blogging
2004 Google Acquisitions
1. 2004-05-10 - Ignite Logic - Web Templates for Law Firms and Small Businesses ; Website creation technology
2. 2004-06-23 - 2.6% Stake in Baidu.com; 2006-06-24 ; Google Sells 2.6% Stake in Baidu.com - Chinese Language Search Engine
3. 2004-07-13 - Picasa - Digital Photo Management ; Photo management software
4. 2004-10-00 - Where 2 Technologies - Digital Mapping (Google Maps)
5. 2004-10-27 - Keyhole Corp - Digital Mapping (Google Earth)
6. 2004-12-00 - ZipDash - Maps and Traffic for Mobile Devices ; Used in Google Ride Finder
2005 Google Acquisitions
1. 2005-01-00 - 2Web Technologies - Google Spreadsheets ; Web-based spreadsheet
2. 2005-01-00 - Phatbits - Widget engine.
3. 2005-03-28 - Urchin Software - Web Analytics Software流量分析
4. 2005-05-12 - Dodgeball - Mobile Social Networking
5. 2005-07-00 - Reqwireless Inc - Java ME Browser ; Web browser and Mobile email
6. 2005-07-07 - Current Communications Group - Broadband Internet (BPL - Broadband over Power Line)
7. 2005-08-17 - Android(mobile phone platform) - Software for Mobile Phones ; Software for Handheld devices
8. 2005-09-15 - Transformic Inc - Search Engines for the Deep Web
9. 2005-11-00 - Skia - Graphics Software Engineering
10. 2005-11-17 - Akwan Information Technologies - Latin American Operations Center (Brazil, Mexico, Latin America) ; Latin American internet operations
11. 2005-12-xx - allPAY GmbH, bruNET GmbH - Mobile Solution Provider, Germany
12. 2005-12-20 - 5.0% Stake in AOL - Internet
2006 Google Acquisitions
1. 2006-01-17 - dMarc Broadcasting - Digital Solutions for Radio Broadcasting Industry ; Radio advertising software and platform.
2. 2006-02-14 - Measure Map - Web Analytics for Blogs
3. 2006-03-09 - Upstartle (Writely) - Web Based Collaborative Document Editor (Online Word Processing)
4. 2006-03-14 - @Last Software - SketchUp 3D Modeling
5. 2006-04-09 - Orion - Referential Search Engine ; Advanced search method.
6. 2006-08-15 - Neven Vision - Automatic Information Extraction from Photos
7. 2006-10-31 - JotSpot Inc - Wiki Technology for Collaborative Websites ; Website applications
8. 2006-11-13 - YouTube Inc - Consumer Media Company (Watch and Share Videos) ; Video sharing (San Bruno, CA)
9. 2006-12-00 - Endoxon - Geo Mapping Software ; Mapping solutions
2007 Google Acquisitions
1. 2007-01-00 - Xunlei (Partial Acquisition) - File Sharing Website ; Network, file-sharing
2. 2007-03-16 - Adscape Media - In-Game Advertising for Video Games ; Video game advertising
3. 2007-03-16 - Trendalyzer - Presentation Software
4. 2007-04-13 - Doubleclick - Advertising Technology Platform
5. 2007-04-17 - Tonic Systems - Presentation Creation and Document Conversion Technology
6. 2007-04-19 - Marratech - Video Conferencing Software ; Video conferencing (Stockholm, Sweden)
7. 2007-05-11 - Green Border Technologies - Secure Connections for Web Browsing and Email ; Desktop enterprise security
8. 2007-05-30~06-01 - Panoramio - Community Photos Website (Works with Google Earth) ; Geospatial Photo-sharing Service
9. 2007-06-01~03 - Feedburner - Feed Distribution and Management Tools ; RSS Feeds (Chicago, IL)
10. 2007-06-05 - PeakStream Inc - Multiprocessor and GPU Software ; Parallel Processing
11. 2007-06-19 - Zenter - Online Slide Presentations
12. 2007-07-02 - GrandCentral Communications - Services for Managing Voice Communications ; VOIP Phone Aggregation (Fremont, CA)
13. 2007-07-xx - ImageAmerica - High resolution aerial cameras
14. 2007-07-09 - Google to Acquire Postini - Services for Message Security, Archiving, Encryption, and Policy Enforcement ; Communications Security (San Carlos, CA)
15. 2007-09-xx - Tusli - Google Blogger Api Engineering Team
16. 2007-09-xx - Zingku - Mobile social network and communication platform
17. 2007-10-xx - Jaiku - An activity stream and presence sharing service that works from the Web and mobile phones (Helsinki)
2007年12月6日 星期四
接觸
Connecting People，這是NOKIA的Slogan原文，在台灣的NOKIA譯解為「科技始終來自於人性」。
「科技始終來自於人性」從這句話裡隱約可以將人與科技表達出一個關係圖：
接觸到精障者照護這個領域，看到整個團隊為精障者付出的努力，和一些已經獲得回饋的成就，更切實感受到以人為本的科技所帶來提昇，不論是物質或精神層面上都有。我感到很榮幸將來能為這個團隊貢獻一份心力。
初次參加月會，在 臺北市立聯合醫院仁愛院區 職業復健轉銜中心 這個地方，我看到了一個溫馨的環境，一些精障學員為了回歸一般社會就業，正努力的練習，而其中有就輔員去幫助、指導他們，牆上也掛了不少學員作品和一些相關成果的照片，整個環境給我的感覺就像一個大家庭(很陽春的比喻，但是非常切實)，家長(就輔員)不辭辛勞的為了幫助子女(精障學員)展翅翱翔在天空去豐滿他們的羽翼，而我想對就輔員最大的回饋就是學員們的成功獨立了。
對於其他就輔員層級的與會人士，當天好像沒有全部出席，不過每個就輔員給我的感覺都是非常專注於協助我們開發輔具，在會議中，每個人從他們的經驗中提出很多看法，無論最終是否採納，大家都熱切討論，使得相關輔具的開發和制定輔具測試的過程中增加了很多新的思路，大家也熱心的參予、協助測試的工作；其中讓我印象最深刻的，就是仁愛院區的就輔員 陳麗凰組長；我想應該是由於擁有一顆充滿愛並散播愛的心再加上長期接觸精障人士，組長第一眼給我的感覺，除了親切還是親切；除此之外，在會議中，我原本以為長期從事輔導工作，這種有關人文關懷的人士會對科技的應用與瓶頸可能不是那麼清楚，但是組長的意見每每讓我感受到他對我們研究工作有著清楚的認知，不禁讓我對組長背後所付出的努力致上最大的敬意，當然也不小心曝露出我的孤陋>"<。
在會議議題裡，對於團隊中，各位教授、學長和先進在輔具方面的研究和探討出現的結晶，去深入了解後，在其背後隱藏的無一不是經過了眾人集思廣益和重重磨難後才得來的；很多企業都在講求企業社會責任(CSR)的時代下，我想我們團隊明白的表現出我們對社會的付出，成功的展現對校園社會責任的擔當。
2007年11月10日 星期六
Homework 10/27/2007
1. Read and then comment on the following papers.
Yao-Jen Chang, Shan-Yao Wu, Ting-Liang Shih, Intersection Location Service and Performance Comparison of Three Location Service Algorithms for Vehicular Ad Hoc Networks in City Environments
Yao-Jen Chang, Tseng-Yun Wang, Shi-Kai Tsai, Yu-Chia Chuang, "Action Science Approach to Experimenting Nonprofit Web 2.0 Services for Employment of Individuals with Mental Impairments" 2007 International Workshop on Social Media Analysis in conjunction with ACM/IEEE Web Intelligence 2007. (EI)
在Web 2.0的理念下，blog展現了良好的互動反應能力；以人為本，事為主的交流形式更能提昇資訊的查找與使用，但是資訊快速流通就必須注意到某些資料的隱密性，另外如果在共同編輯的blog上參與的人過多，或是過於良莠不齊，就必須將"管理"做好，這會對管理者產生ㄧ些額外的負擔。
2. Why is CSMA/CA instead of CSMA/CD used for 802.11?
因為在802.11的應用範圍內，由於無線傳送包含隱藏終端問題(A B C
C不在A的範圍A也不在C的範圍，他們又同時傳給B)，路徑的準位變動相對大很多，所以對於Collision Detection是無法達成，就採用需要較長時間的Collision Avoidance。
Yao-Jen Chang, Shan-Yao Wu, Ting-Liang Shih, Intersection Location Service and Performance Comparison of Three Location Service Algorithms for Vehicular Ad Hoc Networks in City Environments
nILS可以說是一套專門為都市街道環境設計的Vehicular Ad Hoc Networks 演算法，考量到形成Ad Hoc Networks需要一定數量的peers，所以都市街道環境就是一個最佳環境，而ILS也在模擬中表現優於另兩種知名的演算法，足以證明其設計規劃的成功。
Yao-Jen Chang, Tseng-Yun Wang, Shi-Kai Tsai, Yu-Chia Chuang, "Action Science Approach to Experimenting Nonprofit Web 2.0 Services for Employment of Individuals with Mental Impairments" 2007 International Workshop on Social Media Analysis in conjunction with ACM/IEEE Web Intelligence 2007. (EI)
在Web 2.0的理念下，blog展現了良好的互動反應能力；以人為本，事為主的交流形式更能提昇資訊的查找與使用，但是資訊快速流通就必須注意到某些資料的隱密性，另外如果在共同編輯的blog上參與的人過多，或是過於良莠不齊，就必須將"管理"做好，這會對管理者產生ㄧ些額外的負擔。
2. Why is CSMA/CA instead of CSMA/CD used for 802.11?
因為在802.11的應用範圍內，由於無線傳送包含隱藏終端問題(A B C
C不在A的範圍A也不在C的範圍，他們又同時傳給B)，路徑的準位變動相對大很多，所以對於Collision Detection是無法達成，就採用需要較長時間的Collision Avoidance。
2007年9月29日 星期六
Homework 9/22/2007
1. Read and then comment on the following papers.
Yao-Jen Chang, Shih-Kai Tsai, Tsen-Yung Wang Wayfinding Systems Based on Passive RFID for Individuals with Cognitive Impairments
Yao-Jen Chang, Tseng-Yun Wang, Yu-Chia Chuang, Shih-Kai Tsai, “Ontology-based Personalized Wayfinding System Using Deviation Detecting for Individuals with Cognitive Impairments” to be presented in International Conference on Convergence Information Technology 2007, Gyeongju, Korea. November 21~23, 2007. (EI)
這幾篇研究RFID在定址、路徑導引方面的應用
RFID的優點
1.除了天線外之所有元件皆己做成晶片,可有效降低成本。
2.使用無線傳能,不必使用電池不用擔心電池秏盡的問題。
3.晶片密碼為世界唯一無法複製COPY，安全性高。
4.可製成各種包裝類型, 以應用在各種不同場合。
5.採近接式讀卡, 不用和讀卡機直接接觸、不用刷卡所以不怕接點髒污及磨損, 可放置於口袋、皮包內，不必取出就能直接辨識,增加使用上的便利性。
6.標籤資料可重新由讀卡機更改,用完可回收再利用。
7.使用壽命長。(BY RFID技術概論 林禹臣)
由於RFID傳輸距離最長也僅5m(UHF頻段)，所以用來定址還蠻合適的，不會造成互相干擾，但是考慮RFID reader價格並不便宜，相較之下，採用QR碼就經濟多了；但是就便利性來講，RFID又比較佔優勢(感應取得資訊，QR碼需利用攝影，再傳送取得的圖片)；又由於NOKIA、BenQ等手機業者開始將感應式IC卡內嵌到手機中，用的是NFC(Near Field Communication)技術，所以有些淺見，那可否考慮將reader與tag交換，在需要偵測的位置放置reader，由reader感應不同使用者再經網路將導引圖片傳至手機，主要成本也只有佈置reader而已，後續增加用戶的成本則可以大大縮短。
2. Read Sec. 1-3-6 of Textbook.
What is the disadvantage of Mobile IP and what's the solution?
傳輸路徑是三角形(Triangular Routing of Data)。這種路徑雖然是有效的路徑，但是卻沒什麼效率；當MN快速移動時，就不敷使用。
(1).行動IP機制中的另一項重要特性即藉由網路芳鄰找尋(Neighbor Discovery)與自動定址(Auto-configuration)機制來簡化使用者IP位址的設定。
(2).使用IPv6，IPv6網路上的主機可自動取得IP不需透過手動設定。而利用Extension Header的Destinetion Header與Routing Header，將使行動通訊中之路由機制獲得最佳化，解決了三角路由( triagle route)的問題。
3. According to lecture notes on Page 2, what is social network? Why is the positioning a major factor in mobile social network service?
Social networks are personal or professional sets of relationships between individuals.
社會網路(social network)是一組演員及一套讓演員組合在一起的關係所構成。演員可以是個別性的, 也可以是一個集合單位, 諸如部門、組織、或家庭。 關鍵在於演員們彼此交換資源並將之聯結(connect) 在一社會網路中。這些資源可能包括資料(data)、資訊(information)、財貨(goods)、社會支持(social support)、或財務支持。每種資源交換都是一種社會網絡關係(social exchange relations), 而維繫此種關係的個體(individuals) 都可稱為維繫一種聯結點(tie)。每個聯結點的強弱端賴所交換資源的數目及類型、交換頻率、及彼此間交換的私密性而定強弱而定(Marsden & Campbell, 1984)。 http://blog.forlady.net/2006/04/social_networkc.html
用部落格來舉例，一個部落格可能是一個人或一群人支持的，而一個部落格又可能連繫很多相關部落格；而連繫部落格間就必須要有每個部落格的位置，要形成mobile social network service，就需要每個部落格的位置去支持它實現。
Yao-Jen Chang, Shih-Kai Tsai, Tsen-Yung Wang Wayfinding Systems Based on Passive RFID for Individuals with Cognitive Impairments
Yao-Jen Chang, Tseng-Yun Wang, Yu-Chia Chuang, Shih-Kai Tsai, “Ontology-based Personalized Wayfinding System Using Deviation Detecting for Individuals with Cognitive Impairments” to be presented in International Conference on Convergence Information Technology 2007, Gyeongju, Korea. November 21~23, 2007. (EI)
這幾篇研究RFID在定址、路徑導引方面的應用
RFID的優點
1.除了天線外之所有元件皆己做成晶片,可有效降低成本。
2.使用無線傳能,不必使用電池不用擔心電池秏盡的問題。
3.晶片密碼為世界唯一無法複製COPY，安全性高。
4.可製成各種包裝類型, 以應用在各種不同場合。
5.採近接式讀卡, 不用和讀卡機直接接觸、不用刷卡所以不怕接點髒污及磨損, 可放置於口袋、皮包內，不必取出就能直接辨識,增加使用上的便利性。
6.標籤資料可重新由讀卡機更改,用完可回收再利用。
7.使用壽命長。(BY RFID技術概論 林禹臣)
由於RFID傳輸距離最長也僅5m(UHF頻段)，所以用來定址還蠻合適的，不會造成互相干擾，但是考慮RFID reader價格並不便宜，相較之下，採用QR碼就經濟多了；但是就便利性來講，RFID又比較佔優勢(感應取得資訊，QR碼需利用攝影，再傳送取得的圖片)；又由於NOKIA、BenQ等手機業者開始將感應式IC卡內嵌到手機中，用的是NFC(Near Field Communication)技術，所以有些淺見，那可否考慮將reader與tag交換，在需要偵測的位置放置reader，由reader感應不同使用者再經網路將導引圖片傳至手機，主要成本也只有佈置reader而已，後續增加用戶的成本則可以大大縮短。
2. Read Sec. 1-3-6 of Textbook.
What is the disadvantage of Mobile IP and what's the solution?
傳輸路徑是三角形(Triangular Routing of Data)。這種路徑雖然是有效的路徑，但是卻沒什麼效率；當MN快速移動時，就不敷使用。
(1).行動IP機制中的另一項重要特性即藉由網路芳鄰找尋(Neighbor Discovery)與自動定址(Auto-configuration)機制來簡化使用者IP位址的設定。
(2).使用IPv6，IPv6網路上的主機可自動取得IP不需透過手動設定。而利用Extension Header的Destinetion Header與Routing Header，將使行動通訊中之路由機制獲得最佳化，解決了三角路由( triagle route)的問題。
3. According to lecture notes on Page 2, what is social network? Why is the positioning a major factor in mobile social network service?
Social networks are personal or professional sets of relationships between individuals.
社會網路(social network)是一組演員及一套讓演員組合在一起的關係所構成。演員可以是個別性的, 也可以是一個集合單位, 諸如部門、組織、或家庭。 關鍵在於演員們彼此交換資源並將之聯結(connect) 在一社會網路中。這些資源可能包括資料(data)、資訊(information)、財貨(goods)、社會支持(social support)、或財務支持。每種資源交換都是一種社會網絡關係(social exchange relations), 而維繫此種關係的個體(individuals) 都可稱為維繫一種聯結點(tie)。每個聯結點的強弱端賴所交換資源的數目及類型、交換頻率、及彼此間交換的私密性而定強弱而定(Marsden & Campbell, 1984)。 http://blog.forlady.net/2006/04/social_networkc.html
用部落格來舉例，一個部落格可能是一個人或一群人支持的，而一個部落格又可能連繫很多相關部落格；而連繫部落格間就必須要有每個部落格的位置，要形成mobile social network service，就需要每個部落格的位置去支持它實現。
2007年9月28日 星期五
Homework 9/15/2007
1. Translate or rewrite the abstract of the following papers.
Wayfinding Systems Based on Geo-coded QR Codes and Social Computing for Individuals with Cognitive Impairment, (accepted as a Journal paper.), to be presented in International Conference on Convergence Information Technology 2007, Gyeongju, Korea. November 21~23, 2007. (EI)
一種新的路徑導引系統是為了增進認知障礙病人，如:腦創傷、腦性麻痺、智能缺陷、精神分裂及阿茲罕默的病人們在工作場合及日常生活的獨立能力被發明。它是基於在一種地理編碼"QR碼"上嵌入座標(X、Y、樓層)和社交性的運算並有利於縮短使用者學習時間。根據空間導航的心理模型和專業協輔人士的要求，PDA在對的時間和位置提供空間影像能幫助認知障礙人士在室內及道路上的導航。為了這麼做，地理編碼"QR碼"可被想成一種新的交通號誌系統，被佈告在路徑上所選的位置。當使用內建相機的PDA拍攝視線內的QR碼時，導航地圖就會被提供給發出需求的使用者。一個追蹤的功能被整合在參訪位置的時間戳記上且在異常狀況時提出警告。這追蹤系統增加了保護機制的判斷能力，並且也降低接受輔助科技的入門障礙。路徑導引設備組成的原型，包含教學部落格和追蹤系統，在大學校園設計並測試。相較於感測器網路方法，QR碼較容易且快速發展，成本也是比較低的。經實驗結果顯示，人機介面是親切的，且路徑導向的能力是可信賴的。
A General Architecture of Mobile Social Network Services, to be presented in International Conference on Convergence Information Technology 2007, Gyeongju, Korea. November 21~23, 2007. (EI)
廣泛的使用手機和提供用戶位置訊息是促使個人區域地位的運用。現今訂購服務主要是在滿足娛樂,備忘錄和尋找朋友或著家人的需要在這個研究裡,我們發現MSNSs在手機中社會網路服務的淺在價值。研究是從使用移動手機社會網路服務去衡量大多數人的社交數量和增進生活品質，除此之外，失業員工，很少獲得適當的社區服務，並在社會上受到孤立。互動式的媒體，基本區域定位，已經提出滿足經常出現在該領域的工作提供支持的社會服務。結合位置搜尋技術和個人資料配對，推薦的模式和總體結構可以讓社會工人，同事和其他的專業人員保持互通，通報，和組織一個像活動的社區並給予需要的人幫助。提示結構的其中一個優點是沒有新的定位單元需要實行內部的Wi-Fi去分配網路或無線核心網路。此外，混合網路服務的使用，這種方法使結構更加單元化和易於利用現有的網絡服務。範例已經實施而且結果已經呈現出來。
2. Read Sec. 1-1, 1-2 of Textbook and the presentation materials in class.
What is the key factor which contributes to the integration of various media such as data, voice, and video on a single platform?
ALL IP
3. What are the major differences between wireless and wired communication?
Multipath；Fading；Interference；Hidden Terminal
Wayfinding Systems Based on Geo-coded QR Codes and Social Computing for Individuals with Cognitive Impairment, (accepted as a Journal paper.), to be presented in International Conference on Convergence Information Technology 2007, Gyeongju, Korea. November 21~23, 2007. (EI)
一種新的路徑導引系統是為了增進認知障礙病人，如:腦創傷、腦性麻痺、智能缺陷、精神分裂及阿茲罕默的病人們在工作場合及日常生活的獨立能力被發明。它是基於在一種地理編碼"QR碼"上嵌入座標(X、Y、樓層)和社交性的運算並有利於縮短使用者學習時間。根據空間導航的心理模型和專業協輔人士的要求，PDA在對的時間和位置提供空間影像能幫助認知障礙人士在室內及道路上的導航。為了這麼做，地理編碼"QR碼"可被想成一種新的交通號誌系統，被佈告在路徑上所選的位置。當使用內建相機的PDA拍攝視線內的QR碼時，導航地圖就會被提供給發出需求的使用者。一個追蹤的功能被整合在參訪位置的時間戳記上且在異常狀況時提出警告。這追蹤系統增加了保護機制的判斷能力，並且也降低接受輔助科技的入門障礙。路徑導引設備組成的原型，包含教學部落格和追蹤系統，在大學校園設計並測試。相較於感測器網路方法，QR碼較容易且快速發展，成本也是比較低的。經實驗結果顯示，人機介面是親切的，且路徑導向的能力是可信賴的。
A General Architecture of Mobile Social Network Services, to be presented in International Conference on Convergence Information Technology 2007, Gyeongju, Korea. November 21~23, 2007. (EI)
廣泛的使用手機和提供用戶位置訊息是促使個人區域地位的運用。現今訂購服務主要是在滿足娛樂,備忘錄和尋找朋友或著家人的需要在這個研究裡,我們發現MSNSs在手機中社會網路服務的淺在價值。研究是從使用移動手機社會網路服務去衡量大多數人的社交數量和增進生活品質，除此之外，失業員工，很少獲得適當的社區服務，並在社會上受到孤立。互動式的媒體，基本區域定位，已經提出滿足經常出現在該領域的工作提供支持的社會服務。結合位置搜尋技術和個人資料配對，推薦的模式和總體結構可以讓社會工人，同事和其他的專業人員保持互通，通報，和組織一個像活動的社區並給予需要的人幫助。提示結構的其中一個優點是沒有新的定位單元需要實行內部的Wi-Fi去分配網路或無線核心網路。此外，混合網路服務的使用，這種方法使結構更加單元化和易於利用現有的網絡服務。範例已經實施而且結果已經呈現出來。
2. Read Sec. 1-1, 1-2 of Textbook and the presentation materials in class.
What is the key factor which contributes to the integration of various media such as data, voice, and video on a single platform?
ALL IP
3. What are the major differences between wireless and wired communication?
Multipath；Fading；Interference；Hidden Terminal
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