Knowledge sharing and yahoo answers: Everyone knows something

Some Research of this Paper:

• a user asks for information on how to read a file using the C programming language.

• Who is the better actress, Angelina Jolie or Jennifer Aniston?

• The author has also done some research in 4.4 Expertise depth, regarding the YA reply depth is not high.

• 5.1 Relationships between categories Fig 6 (a)、(b) Unexpectedly may pull in view of Similarities between categories with cosin relates, is really mysterious.

1. Jokes、Polls get few length.
2. In this Graph Programming, Chemistry, and Physics will tend to attract few replies

Seeks the suggestion, opinion, YA may provide the general response, but especially in the programming language and so on in the specialized question and answer, the depth which obtained arrives is insufficient, but regarding the general question which like
user and so on family is familiar with, actually may obtain many different responses, generally speaking YA is very good obtain suggests the way.

Questions:

• In 3. YAHOO ANSWERS AND DATA SET Part：we harvested one month of YA activity. The dataset includes 8,452,337 answers to 1,178,983 questions, with 433,402 unique repliers and 495,414 unique askers. How did he get this DataSet?
  

How to Get Fulltext:

• First, Enter ACM from Here。
• Search Keywords: expertise finding, help seeking, knowledge sharing, online communities, question answering, social network analysis

Reference:

• Knowledge sharing and yahoo answers: everyone knows something

• WWW '08: Proceeding of the 17th international conference on World Wide Web

PS: This paper looked quite several days, but also did not have the means completely to understand, looks at long time but only to write several characters. 2008/06/09.

Homework-03-28-2008

Homework-03-28-2008
1. Read the abstract of Paper 3, 6 and 7. If possible, skim the whole paper. Summarize the papers briefly.
Ans:

• Paper3：Social Network Analysis to Blog-based Online Communities Summary：Social Network Analysis is used as a research vehicle to investigate the structural patterns of blogging communities. SNA is a sociological methodology for analyzing patterns of relationships and interactions between social actors in order to discover the underlying social structure.Not only the attributes of social actors, such as their age, gender, socioeconomic status, and education, but also the properties of relationships between social actors, such as the nature, intensity, and frequency of the relationships, are believed to have important implications to the social structure. SNA methods have been employed to study organizational behavior, interorganizational relations , citation patterns, virtual communities , and many other domains.
  Reference:
  Osmand's Paper 3
  Summary of paper 3
  

• Paper6：Mobile Computing for Indoor Wayfinding Based on BluetoothSensors for Individuals with Cognitive Impairments
  Summary：In this paper, Bluetooth is used for personal way finding purposes where Bluetooth beacons and ID scanning are used, but no device inquiry, time-consuming pairing, or information exchange does happen. Bluetooth operated in this discovery mode saves power, eliminate manual passkey challenges, and reduce privacy and security concern as the use does not expose her ID. Based on the Bluetooth beacon received, the position where the user is can be identified at the remote server and enable the way finding sequences. The Bluetooth sensors can automatically be read from several meters away and does not have to be in the line of sight of the reader.
  Reference:
  Buddhi 's Summary of paper 6
  Osmand's Paper 6
  

• Paper7：Action Science Approach to Experimenting Nonprofit Web 2.0 Services for Employment of Individuals with Mental Impairments
  Summary：In this paper, the Authors proposed the project called Nonprofit 2.0 based on Web 2.0 technology. The goal of this project is to submit new approach that could be implemented by the Taiwan Government to provide better facilities and treatments to the citizen who are get mental ilness.The Authors created a prototype which was tested by the job coaches one month after the survey and extensive field study. The user feedback will be our guidelines to further improve the prototype. In the designed architecture, we provide four solutions as database of employers, database of employment service, database 289 of mental disabled persons, and software package for briefing candidate employers.
  Reference:
  Buddhi's Summary of paper 7
  
  Osmand's Paper 7
  
  

2. According to Chap. 6 of Textbook. what is a functional architecture of e-commerce systems?
Ans:A functional architecture of e-commerce systems consists of several components with its own unique functions that linked together. There are four primary components of e-commerce systems:

• a. Client: computer system, typically a PC, which is connected to the internet. Usually used by buyer to browsing and/or purchasing. (e.g.: home PC, PC of buyer's company).
  

• b. Merchant: computer system or systems that contain the seller's electronic catalog and, in the case of online goods, products for over-the-Net fulfillment. (e.g.: content servers).
  

• c. Transaction system: computer system or systems that process a particular order and that are responsible for payment, record keeping, and other business aspects of the transaction. (e.g.: application servers).
  

• d. Payment gateway: computer system that routes payment instructions into existing financial networks such as for credit card authorization and settlement. (e.g.: resource managers).

3. Lab: PageRank :PageRank is a tool for measuring the importance of websites. Given every URL, there is a PageRank value for it.
Ans:

CNN(9/10)







New York Times(9/10)









Jack's HomeWork Center( 3/10 )
Ha It should be wrong number. I'm use firefox browser.

What are the commercial values of Internet

Homework 3-8-2009

1. Track your comments at a focal point
A: already done.

2. Using personal portal.
A:already done.

3. Make your blog organized by adding labels
A:already done.

4. Reading Assignments: Read Chap 3. Answer the following questions.
Q:already done.

What are the commercial values of Internet?
List some business strategies for online commerce.
A:Reading....Comming soon!

what is the commerce value chain

Homework 3-01-2008
Q1. According to the book by Treese and Stewart, what is the commerce value chain? Why not see them on an individual basis?

A1: The components of general commerce value chain are as follows

• Attract customers: Marketing - get and keep customer interest.
• Interact with customers: Sales - turn interest into orders( generally content ).
• Act on customer instructions: Order management - order capture, payment, fullfillment.
• React to customer requests: Customer service, technical support.

But I don't think so , Although most individuals are unable to load, but many in Yahoo, ebay auction of the individual, Also to the above-mentioned four parts in the Internet.

For example:小婷電腦，she has four parts similar to the above, Weekly email latest weekly goods, orders to meet customer needs.

Q2. Is the Internet different from other media? Why?

A2:

• Time: No time difference restrictions on the Internet 24 hours of service.
• Space: No geographical restrictions, even thousands of kilometres apart, can be a very short time to spread the message throughout.
• Free: All information not spend a dime of money readily available.
• Exchange: All information can be exchange more transparent.

For Example:

• More and more people, do not read the newspaper in Taiwan, They don't have so much time to read itand they read the news in the Internet like Yahoo, Msn News. The higher cost of human society, newspapers from the Internet was replaced by the more serious cases.
• Many people looking for job not looking at newspaper, but to http://www.104.com.tw/.

Q3.Convert one of your Word document using Google docs.

A3:

• This is the HELLO_WORLD sample at Google docs.
• You can view the Hellow_world.c here in my blog.If you do any change in hello_world.c , just press Publish->Republish post then you will see the new Hellow_world.c in blog.

Q4. Customize your blogs.
A4:I already done it before!

The companies Google acquired year by year.

1. List the companies Google acquired year by year.Briefly describe the strategic implications of each acquisition.

Q1:

• May 30, 2007: Panoramio: Link photograph and google earth.
• May 29, 2007: GreenBorder Technologies is a maker of browser-based security software, protect the software and web application of google.
• April 2007: Tonic Systems: Add presentation sharing and collaboration capabilities to Google Docs & Spreadsheets .
• April 2007: Marratech Google plans to use the software for its employees, and has not yet announced any plans to market the videoconferencing technology.
• March 2007: Adscape Media which makes technology for placing advertisements in video games.
• March 2007: Gapminder Trendalyzer makes statistics more understandable by converting numbers into interactive animations.
• December 2006: part of Endoxon : bolster European maps.
• October 2006: YouTube for $1.65 billion :bolstered its video search engine with YouTube content.
• October 2006: JotSpot : which makes wiki technology for collaborative Web sites.
• August 2006: Neven Vision : mobile photo search.

Ref: What Google bought in the past 12 months from NetworkWorld.

What Is Web 2.0 by Tim O'Reilly

Summarize the What Is Web 2.0 by Tim O'Reilly in one page.
Q2: Web 2.0 and no precise classification, Tim O'Reilly proposed a complete and specific description of the so-called Web 2.0 concept, citing the DoubleClick vs Google AdSense , Ofoto vs Flickr , such as Akamai vs BitTorrent...

A Platform Beats an Application Every Time

For example below: I don't need to know how to program or make the map,but I can show my location information in my blog! Just use "Embedded code" that you can get it from google map.

This is WEB 2.0!!!

檢視較大的地圖


google provided a lot of API allow for the kind of people who do not know how to program can also focus on the drafting of the contents, no doubt the information is a great help to spread, the same WEB2.0 is the same concept.

Finally O'Reilly had point out some key principles of Web 2.0 Design Patterns that we should be rethinking the idea of the past already know.

• The Long Tail.
• Data is the Next Intel Inside.
• Users Add Value.
• Network Effects by Default.
• Some Rights Reserved.
• The Perpetual Beta.
• Cooperate, Don’t Control.
• Software Above the Level of a Single Device.

Ref:

1. What Is Web 2.0 by Tim O'Reilly.

2. Web 2.0 From Wikipedia.

3. What is Web 2.0?! from Rex’s blah blah blah.

Compare the business models of Metropolitan Wi-Fi Networks in the world

1. Compare the business models of Metropolitan Wi-Fi Networks in the world.
Comment：

1. 首爾,韓國
上網的費用約 10Mbps = $20 US, 是個遊戲產業非常發達的國家, 有著大量的電信公司SK, KT, 三星, LG等.

2. 台北,台灣
WiFi上網的費用約在 $5-$12 US, 恩看起來是我們是蠻便宜的，不過普及率就台北北高雄而以。
有線網路的比較看來就差人很多, 貴了不少。

3.日本, 東京
NTT每月 $50 US 100M , $90 US 1G 光纖, 這讓我們這種鄉下來的, 很難去想像, 家裡要1G光纖做甚麼用途? 抓電影嗎? 這要去日本一趟才知道他們拿來做甚麼用途。

4.中國, 香港
HKBN 上網費用 10Mbps = 16US, 100Mbps = 34US, 還有能提供視訊會議及電化訊息用的網路 $6 US.

5.新加坡
上網費用 30Mbps = $77 US, 相較於其它亞洲國家偏貴, 但該國普級率達 65%, 並計畫著下一個十年現代化的目標. 改進到 IPV6 及 1Gbps 的能力, 看來是朝日本目標邁近。

6.瑞典, 斯德哥爾摩
TeliaSonera 上網的費用 24M=$50 US, 綁約, 20 per month, 木前也是正計畫WiMax 推展.

7.美國
城市很多, 有些城鎮也是免費的居民使用。使用率也是參疵不齊, 地大對於無線發展應該也是個有利的發展, 至少省下了線材跟維修。

8法蘭西, 巴黎
法蘭西 Telecom 上網費用 18Mbps = $45 US,包函VOIP, 數位電視, 並預計五年內提升到50Mbps, 及高解析度的影像傳送,並把目標定於 2.5Gbps的光纖網路及也在考慮推展 WiMax.

9.SHOREDITCH, 英國
上網費用 8M = $40 - $80 US, 比起其它國家算蠻貴的, 但該國家物價水準本來就比較高，不太能統一比較，將寬頻應用於電視及監控用途.

10.矽谷, 美國
WiFi上網 - Free, 不愧是高科技地區。雖然是1Mbps的無線網路, 但傳傳訊息、email也很好用。

比較了幾個國家，雖然不全然都是無線，但從此看的出發展的端倪，無線網路相較於有線有著許多的優勢，
加上802.11n的出現，速度的差異性已不像以往那麼巨大，隨著技術的提升，價格的下降，漸漸的數位化的
城市，將如同電影的場景指日可待了。


2. Read the abstracts of the full papers, and then make your comments.
Robin Kay, Developing a comprehensive metric for assessing discussion board
effectiveness, British Journal of Educational Technology, Vol 37 No5 2006. pp. 761-783Comment：

這篇文章舉出了12種領域來評估論談, 並找45個學生, 年齡在 13-15歲分成兩組, 花了一年的時間做的研究。
1.社會學習(social learning)
2.認知處理(congnitive processing)
3.討論品質(quality of discussion)
4.起始問題(Initial question)
5.教育者的角色(role of educator)
6.領導議題(navigation issues)
7.學生的挑戰(challenges for students)
8.使用者的類型(types of users)
9.對討論者的態度(attitudes towards discussion)
10.回覆時間(response time)
11.學校外學習(learning outside of school)
12.學習成果(learning performance)

根據研究的結果, 論壇上討論的事項大多是有關上課或是超出課程範圍的事, 而會回應的人卻不多，看的人佔大多數主要的討論是問問題或是提供答案，有些人習慣是自行上網查尋或是直接問同學。
論壇與Blog 相較，是有蠻大的不同, 論壇必須要有人管理，並清楚分類，達到較有效的做資訊保存，而不是到處散落的資料，Blog 雖然有很大自我空間，但對於資訊的分類並不是像論壇一樣的清析明白。但Blog 卻有著Web 2.0的優勢, 多樣化的工具，在教育方面的確佔有不少優勢。

Empirical analysis of online social networks in the age of Web 2.0. Homework-12-15-2007

1. Read the abstracts of the full papers, and then make your comments.Feng Fua, Lianghuan Liua, and Long Wang. Empirical analysis of online social networks in the age of Web 2.0, Physica A: Statistical Mechanics and its Applications Volume 387, Issues 2-3, 15 January 2008, Pages 675-684

在這篇論文裡，以經驗法則的分析數據提出了兩個重要的差異，Blog and SNS。 此外，還分別研究degree(in/out) and degree(in/out) ，clustering coefficient and degree和受歡迎度 and in-degree 之間的關係。
文中的分析部落格網路是沒有分類的混合格式，但SNS是有分類的。
如Sina blog、Xiaonei SNS，前者是第一大華人blog提供者，後者是中國最大且最受歡迎的SNS( 大學生only ) ，兩者都有 small-world and scale-free的特點。
Web 2.0 提供了一個趨勢、想法與資訊的機會，social network 讓人與人之間的距離更縮短了，知識的傳遞更為快速且集中，毫不懷疑的BLOG、SNS會日漸的重要且受歡迎。

Homework-Quadrupling Wi-Fi speeds with 802.11n

Quadrupling Wi-Fi speeds with 802.11n

| View | Upload your own

Homework 12-8-2007

Q1. Read the abstracts of the full papers, and then make your comments.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)

A:評估使用"社交多媒體"來進行教授電腦程式設計摘要:
在到處都是電腦的實驗教室裏，追踨學生的進度及分派個人的作業，是一種教學挑戰。當完成了一項實驗後,學生們都會被要求把結果放到他們個人的部落格裏並且在老師的部落格裏留下這個結果的超連結。
使用這種方式可以讓老師很立即的知道學生們的超連結並檢查他們的進度然後馬上跟學生進行討論，我們也會使用部落格這個工具來做社交學習。藉由瀏覽同學做出的東西及老師在同學部落格留下的建議，學生們將很容易互相激發一些新的不同的想法出來。調查結果顯示學生們還蠻滿意使用部落格繳交實驗課程結果的方式，也漸漸習慣在課當上使用這樣的方式來和老師互動及社交學習。

目前我們就是用這種方式在交作業 ，偷抄很容易，被發現也很容易，但對於非資訊本科學生，不但能學習Blog使用，更能學習其它相關的工具，在網路上搜尋答案的技巧更是提升一級。

Q2:Yao-Jen Chang and Chiu-Hui Chen, "Methodology and Evaluation of Teaching Computer Programming Laboratory with Social Media," ED-Media 2007, Vancouver, Canada, June 25-29, 2007.

A: Web 2.0 讓使用者從 content consumers, 轉變成為 content consumers，這是一個很大的突破，
使用者無需對於軟體或硬體技術有很深的瞭解，就可以做出讓人滿意的網頁，而專注於開發或表現自己的專業或資訊，如Blog、WIKI，而有相當多的 技術提供也能應用， 如 Google Map、SlideShare ，能提供影音甚至於地理位置資訊，這些在1.0時代是需要相當的技術一般人才辦的到的。
在這篇論文對於非營利組織所做的實驗，業主的資料庫、政府的規範、Blog 提供的討論及網路訓練等。Web 2.0是很好的架構，它的特性剛好可以滿足經費的問題，對於心理上曾有缺陷的人的教育訓練、或是展示它們自己給顧主或是社會大眾都是一個很好的工具。

WiMax 產業分析報告心得

一、查詢近期WiMax 產業分析報告ㄧ篇，作成100字摘要。
從Intel WiMax Road Map 來看，明年起將針對Notebook、Handset、 mobile等Device support WiMax，加上其積極的佈局整個產業鏈， 未來WiMax有可能會成為今日的802.11b，內建在notebook之上。許多間的產品整合了記憶體、MAC、PHY 在晶片上，耗電量也達到150mW - 350mWSEQUANS也有ARM9+DSP 的產品，查了一下這顆，是MAC + PHY solution, 350mw不過並沒有提到CPU Platform的資訊。

以這些現況來看，目前WiMax還處於燒錢的階段，雖然在傳輸方面有著極大的優勢, 且還有許多存在的問題，移動的穩定性，要達到像3G依樣的穩定、各家的互通性及 耗電量等，將會影響整個普及的時間。

二、簡述 Qualcomm收購 Airgo 與 RFMD 藍牙團隊的策略佈局為哪三項?
1.取得 Airgo 的專利權，不僅拿了技術補強自身不足且有了專利免死金牌，自用賣人兩者皆優.
2.補齊完整的通訊解決方案，加強 RFID 及 WiFi.
3.以上述兩點，將產品佈局深入 Laptop , mobile，等行動運算裝置，加強競爭力.

三、依據 WiMAX晶片業者發展現況此研究報告，目前全球主要WiMAX 晶片業者有哪幾家?

目前較大的廠商有 Intel、Fujitsu
其他屬較小的IC design 公司
Beceem 同時擁有MAC + PHY技術
picoChip
Wavesat
Runcom
SEQUANS http://www.sequans.com/site/images/sequansSQN1110_datasheet_1-4.pdf

Why does Pure Aloha perform worse than Slotted Aloha?

一. Why does Pure Aloha perform worse than Slotted Aloha?

• 
  1.ALOHA協議(Pure ALOHA) 當傳輸點有資料需要傳送的時候，它會向立即向通訊頻道傳送。
  接收點在收到資料後，會ACK傳輸點。
  如果接收的資料有錯誤，接收點會向傳輸點發送NACK。
  當網路上的兩個傳輸點同時向頻道傳輸資料的時候，會發生衝突，這種情況下，兩個點都停止 一段時間後，再次嘗試傳送。
• 2.分段ALOHA(Slotted ALOHA) 這是對純ALOHA協議的一個改進。改進之處在於，它把頻道在時間上分段，每個傳輸點只能在一個分段的開始處進行傳送。每次傳送的資料必須少於或者等於一個頻道的一個時間分段。這樣很大的減少了傳輸頻道的衝突。
  
  如果假設傳輸點對頻道的使用是符合Poisson分佈 的話,我們可以得以下公式:
  純ALOHA協議:
  S = Ge − 2G
  分段ALOHA協議:
  S = Ge − G
  
  S是通過量, G是提供的流量(每單位時間通過的資料包數量).
  從這個公式我們可以看出, 對純ALOHA來說,當G = 0.5 的時候, S 達到最大值 18.4%. 只有當 G<= 0.5 的時候, 純ALOHA系統才處於穩定狀態. 對分段ALOHA來說, 當G = 1 的時候, S 達到最大值 36%.只有當 G<= 1 的時候, 分段ALOHA系統才處於穩定狀態.
  2. According to Textbook pp. 2-48~2-51, why does 1-persistent CSMA have lower throughput than non-persistent CSMA when generated traffic rate is higher than 1 (G>1)? Why does 1-persistent CSMA have shorter latency than non-persistent CSMA?



• 1. （1-persistent CSMA）原理
  若站點有資料發送，先監聽信道；
  若站點發現通道空閒，則發送；
  若通道忙，則繼續監聽直至發現通道空閒，然後完成發送；
  若產生衝突，等待一隨機時間，然後重新開始發送過程。
  優點：減少了通道空閒時間；
  缺點：增加了發生衝突的概率；
  廣播延遲對協定性能的影響：廣播延遲越大，發生衝突的可能性越大，協定性能越差；

• 2. nonpersistent CSMA）原理
  若站點有資料發送，先監聽信道；
  若站點發現通道空閒，則發送；
  若通道忙，等待一隨機時間，然後重新開始發送過程；
  若產生衝突，等待一隨機時間，然後重新開始發送過程。
  優點：減少了衝突的概率；
  缺點：增加了通道空閒時間，資料發送延遲增大；
  通道效率比 1-persistent CSMA高，傳輸延遲比 1-persistent CSMA大。
  

• REF:
  Poisson分佈 法國數學家西莫恩·德尼·蔔瓦松（Siméon-Denis Poisson）在1838年時發表。
  http://zh.wikipedia.org/w/index.php?title=%E6%B3%8A%E6%9D%BE%E5%88%86%E5%B8%83&variant=zh-tw
  ALOHA協議
  http://zh.wikipedia.org/wiki/ALOHA%E5%8D%8F%E8%AE%AE

ILS/HLS/GLS homework

繳交作業方式Nov-10-2007 11:59 a.m. Due

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

這篇針對都會的街道特性， 提出位置資訊服務眼算法Intersection Location Service( ILS )， 並與 Hierarchical Location Service(HLS), Grid Location Service(GLS)演算法做比較。
透過實驗比較， ILS在街道上車間通訊的位置服務優於其它兩者.
A.車輛移動的方向對ILS, GLS, HLS 影響較大
B.區域面積的影響對 ILS影響小
C.車輛密度對GLS影響小
D.車速對GLS影響較大

車間通訊模式的優點:
1. 不需要龐大的基礎建設費用.
2. 提供更精確的交通資料.
3. 不需要額外的服務費用.
4. 較低的嚴遲時間.

ILS 是以 Chord Algorighm為基礎，具延展性的分散式位置資訊服務， 並以位置為基礎的路由演算法(Position-based routing) 代替傳統的以拓樸為基礎的路由演算法(Topology-based routing algorithm)， 隨著GPS普及化， 在高速移動的無線網路環境下，利用節點位置資訊來決定封包傳送策略的演算法。

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)

過去使用者對於自我的意見、照片甚至是影片皆不易於分享及互動，Web 2.0 讓使用者成為資訊的提供者， 使consumer 變成了contributor， Blog/ WIKI 都是代表性的產物，即使是小孩都能在幾分鐘內建立一個自己的Blog發表自己的意見，使用者不用去關心低層程式設計、資料庫等問題，而專注於”Contain”之上。利用這些優點，建立精障損傷者的分享報告，使每個使用者都能貢獻自己的知識。

2. Why is CSMA/CA instead of CSMA/CD used for 802.11?
CSMA/CD (Collision Detection)用於Ethernet , 在有線網路下利用backoff algorithm,
避免重送時再次發生資料碰狀。

CSMA/CA (Collision Avoidance) 應用於無線網路的protocal ， 在資料傳送前，做出類似RTS/CTS的動作，雖然花費了較高的時間成本，但比整份資料重送來的划算。

“Hidden node”, 在有線網路下, 每個節點都可以知道其它節點的狀態, 但在無線網路, A知道B , B知道C, 但A不一定知道C , 因此用CSMA/CD不能得知collision 的問題, 因此使用CSMA/CA 來避免。

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)(以上論文都收錄在講義裡)

A1:
RFID是個好東東，又可以發射又可以帶資料，只是對於距離跟資料量有所限制。看完這兩篇文章，讓我想到，是否能反過來做? 在醫院裡的病人身上帶著RFID可以讓醫院的Server得知病人位置，體溫、心跳等等資料，對於緊急的狀況可以馬上得知，亦可減少醫院人力的支出，相較於wayfinding 是相反的應用，RFID會移動，而wayfinding 的RFID 是固定的，看起來應該也是好的應用。

Q2. Read Sec. 1-3-6 of Textbook.What is the disadvantage of Mobile IP and what's the solution?

A2-1: Mobile Host經常因Handoff，造成網路的Overhead、Packet loss和Packet delay

A2-2: 階層式架構(Hierarchical Mobile IP)與快速換手(Fast Handoff/Handover) 提供縮短換手延遲方法.

參考:

以 SIP（Session Initiation Protocol）為基礎之802.16e快速換手機制 http://acnlab.csie.ncu.edu.tw/wasn06/CR2/p11.pdf

Comparison of IP Micromobility Protocols http://wise.cm.nctu.edu.tw/wise_lab/course/mobile03/Final_Report/9267566.doc

Q3. According to lecture notes on Page 2, what is social network? Why is the positioning a major factor in mobile social network service?

A3-1: 即由一群有相關性或特定的個人或是群體所組成的, 可以是興趣、嗜好、朋友、甚至是病友討論。

A3-2: 可以提供位置對於某些群體是有必要性的，有位置更是省下許多的時間，例如交友;)

Homework 9/15/2007

Q1-1: Wayfinding Systems Based on Geo-coded QR Codes and Social Computing for Individuals with Cognitive Impairments.
A1-1:一種新的路徑搜尋系統被提出來，是為了幫助有辨識能力傷害的病人如腦部受傷、大腦性麻痺、精神遲緩、精神分裂及阿茲罕默等患者，用來增加他們的工作地點及日常生活的獨立。此系統是建立在嵌入位置座標的地理編碼QR codes以及有助於縮短使用者學習曲線的社交估計之上。根據空間導航的心理模型與重建慣性專業的需求，PDA在正確的時間和位置以空間圖像的提示，可以幫助認知障礙者在室內或道路上的導航。為了達到此目的，幾何編碼QR codes可被想像成是一種新的交通號誌系統且被公告到路徑選擇的位置上。具導航的圖片提供給有需要的使用者，而此使用者是以內建的PDA照相機在視界範圍內拍攝QR Codes。一種追蹤的功能被整合來對參觀的位置作時間戳記並且在異常狀況時提出警示。追蹤系統增加了安全的敏感度，也降低了接受輔助科技的進入門檻。包含了路徑搜尋裝置、訓練部落格和追蹤系統的原型機已被設計並在校園中測試。相較於感知網路的方法，QR Codes更容易且更快速部署且成本也較低。實驗經驗結果證實，具人性化的電腦介面更有親和力且路徑搜尋的能力是可以信賴的。

Q1-2:A General Architecture of Mobile Social Network Services in the Context of Social Services.
A1-2:手機廣泛的使用與使用者所在位置資訊的可用性，簡化了個人定位的應用。在今天存在的預約服務已被定位在娛樂、男女初次約會和找朋友或家人的需求之上。在這個研究，我們探索在社交環境中行動社交網路服務的可行性。這個研究以使用行動社交網路服務當作量測開始，針對許多有才能而未被雇用、很少使用適當社區服務和被社會孤立的人，來增加他們的社交連結及改善他們的生活品質。一種以互動、多媒體和定位為基礎的應用方法已被提出，來針對經常出現在提供支撐性社交服務領域的需求之上。結合定位感知搜尋技術和個人檔案配對，建議模組和一般架構使社會工作者、他們的同事和其他參與專家能保持彼此被連結、被通知與被組織，成為行動社區及成為他們需求支撐的網路。提出架構的一個優點之一是沒有一個新的定位模組必須在Wi-Fi分散網路或行動電話的核心網路中被實作。再者，混合式網路服務這個方法使架構更模組化且更容易和現存的網路並存。原型已被實作且結果已被提出。



Q2:What is the key factor which contributes to the integration of various media such as data, voice, and video on a single platform?REF: Read Sec. 1-1, 1-2 of Textbook and the presentation materials in class.
A2：All IP(因此 data, Voice, Video 能進行快速交換)

Q3:What are the major differences between wireless and wired communication?
A3: 所謂無線，就是利用無線電波來作為資料的傳導，而就應用層面來講，它與有線網路的用途完全相似，兩者最大不同的地方是在於傳輸資料的媒介不同。除此之外，無線電波容易因為週遭地形與環境的影響，而受到許多的多重路徑路徑(Multipath)衰減(Fading)的干擾，造成無線電波的訊號品質降低，而且同一時間收和送是無法同時進行(Interference)。而另一方面，無線網路沒有線的牽絆機動性高，不需佈線施工架設容易，因此無論是在使用之機動性或硬體架設方面都會比有線網路更具有優勢。

Note1: 在網路有個Project http://www.fon.com/tw 目前正進行一個計畫, 讓全世界的人可以share 無線網路, 這個與Social Service 是否漸漸的也搭上橋樑了呢?

Note2: 無線網路目前並沒有看到非常有別於有線網路的應用，VOIP、IPCAM(wireless to PDA) 也許是其中產品，不過皆由有線網路所延伸而來。無線目前也有電力的缺點，如PDA續電的問題。