網路技術發展的日新月異帶領了眾多新網路服務的崛起，例如即時影音串流這類的多媒體服務。但即時影音串流服務所產生的龐大資料流和傳輸延遲時間的嚴格限制也隨之而來的為網路環境帶來許多挑戰，在這些條件下，傳統Server-client拓樸架構將client要求的影音資料以單一鏈結傳輸時，常會因為頻寬不足而面臨嚴重的封包遺失，或是資料流擁擠造成的額外傳輸延遲使得封包無法達到即時性的需求。P2P網路擁有server-client架構所難以達到的規模伸縮性，且對於節點、鏈結失效所引起的傳輸錯誤也較能容忍，更重要的是，它有效的分散了原本負載在少數link上的龐大資料流。因此P2P架構近年來風行於即時影音串流服務。 目前P2P網路的拓樸多是隨意形成，當網路成員規模龐大時，由傳送端出發到遠方的接收端，途中可能經過無數的鏈結，每一個鏈結都會由於頻寬的不足使得資料流遭受某種程度的品質損害，另一方面，對即時影音服務而言，若資料流的累積延遲時間超出可容忍範圍時，無法為使用者接受。 本研究嘗試找出一個較好的拓樸用以傳輸多媒體資料流，使得位於最遠端節點的累積延遲亦能為使用者接受，且資料品質的損害程度最小。我們將之建置成一NP-Complete複雜度的問題模型，名為MLDST。而解法則是修改Dijkstra single-source shortest-path演算法，並加上每個節點承擔下游節點數量及延遲時間限制而來。我們以PlanetLab環境在實際的網路上進行實驗，證實我們的演算法比傳統的Minimum-Spanning Tree及shortest path spanning tree有更好的影像品質。 / Numerous new network services arise with the advanced development of network technologies, such as real-time multimedia streaming services. But challenges to network environment come along with the enormous traffic of data flows and rigorous restriction to transmission delay of real-time multimedia streaming services. Under this circumstance, conventional server-client topology suffers from serious packet loss and packet delay due to the overload of servers and their accessing links. Also, extra transmission delay may make packets fail to meet the requirement of real-timed services. Peer-to-peer network is more scalable than server-client model, and is much more tolerable to the transmission errors caused by node or link failures. More importantly, it effectively distributes load from the server to peers. As a consequence, peer-to-peer service architecture becomes very popular for real-time multimedia streaming services recently. Peer-to-peer networks are mostly formed in random fashion. As the size of network grows, packets may have to travel through numerous links to reach far-end receivers. The quality of data may be damaged by insufficient bandwidth of links. For real-time multimedia services, it is not acceptable to users if the cumulated packet delay exceeds a tolerable limit. Our research is trying to find a better topology to transmit multimedia data flows which makes the cumulated delay of the most-far-end user be tolerable and the damage of data quality is minimized. The problem is modeled as a MLDST problem, which is a NP-Complete problem. To solve the problem, we modified Dijkstra’s single-source shortest-path algorithm by bounding the node degree and adding delay constraint. The experiments were carried out on real network environment through PlanetLab. Experiments show that our algorithm outperforms traditional MST and shortest path spanning tree.

Video-on-demand streaming從90年代就在適當的科技下成為網際網路流量的龍頭，故宮教育頻道在技術上採用TCP-based video streaming，但Video streaming使得負載較一般的伺服器繁重。透過負載平衡來分散負載是可行的方式之一，但在TCP-based video streaming的技術下，還是可能遭遇服務品質之相關議題。而服務品質要求 (Quality of Service, QoS)是用來對使用者適配的服務品質表現，做具體之等級劃分的管理工具，本研究以故宮教育頻道 (iPalace Video Channel; iPalace)為標的，針對其DNS Load Balancing搭配Round Robin的運作背景，提出VM Side QoS及Client Side QoS，在VM Side設定Load rate作為指標、在Client Side則以撥放器的表現為主，設定Initial Buffering Time、Mean Rebuffering Duration以及Rebuffering Frequency共三個指標，並搭配流量的實驗操作，劃分Regular及Class情境來蒐集資料。 在分析後發現，在環境較為一致的Class情境中，Mean Rebuffering Duration與Load Rate及Rebuffering Frequency與Load Rate具有低度正相關。未來，若能在環境及客戶端的變異性有較多的控制及掌握，則可讓資料在蒐集上更為正確，讓後續的分析及探討與實際狀況更為相符。

近年來網路多媒體應用日漸盛行，從聲音、影像到網路電視的應用，皆流行於人們的生活之中。我們可以使用Skype 軟體撥打免費的網路電話或是節費電話，我們也可以使用軟體透過網路來觀賞電視節目，而大部分這類型的應用軟體皆使用點對點的技術來獲取更好的傳輸效率。點對點技術同樣是一項新的、受歡迎的應用。從一開始使用者使用點對點傳輸軟體來下載檔案、分享資料，到現在使用點對點傳輸軟體來收聽音樂、觀賞電視節目。無線網路，特別是IEEE 802.11 無線網路，近年來同樣地受到使用者的廣泛使用。使用者可以在任何一處使用網路，即使是在行走之中使用。多媒體結合無線網路是一項非常好的應用，然而，無線網路的一些基本問題，例如移動、傳輸不穩定，常常會降低網路的傳輸效率。因此，我們提出一個新的移動式點對點串流協定，來解決無線網路上多媒體應用的傳輸問題，讓影音的撥放可以更順暢。 / Network multimedia applications are popular in recent years. From voice over IP, video over IP, to IPTV, they are in people’s life now. We can use Skype to dial a free network call or a cheap PSTN call, and we can use some applications to watch TV programs from Internet. Most of them use peer-to-peer technology to get better performance. Peer-to-peer technology is also a new and popular technique in recent years. People use peer-to-peer software to download files and share data in the beginning, and now they use peer-to-peer software to listen to music, and to watch TV programs. Wireless networks, especially the IEEE 802.11 network, is also popular now. People can access Internet anywhere even they are walking. It's a good idea to use multimedia streaming applications in wireless networks, but however, the essential problems of wireless networks will reduce the performance of these applications, such as mobility, and channel instability. We propose a new mobile peer-to-peer streaming protocol to solve the performance problems caused by wireless networks and let the media be played more continuously and smoothly.

網路使用率逐漸普及、傳輸技術的進步以及通訊網路蓬勃發展，提供人們許多生活上的便利，無線網路已經成為現代通訊市場上的新寵兒。其中，IEEE於1999年開始制定與修正WiMAX，此協定在無線網路的應用視為解決”最後一哩”接取問題的利器。然而，無線網路仍舊會遇到傳送訊號耗弱、通訊死角或是氣候干擾等種種原因造成傳輸失敗的問題。 MPEG-4編碼上，考慮影音封包具有不同重要性的意義，針對影音封包需制定不同的重傳機制，本研究先行改善WiMAX中ARQ（Auto Repeat Request）的流程，再利用跨層設計使得MAC層可以辨識影音封包資訊，確保GOP-tree中之＂骨幹＂節點穩定的抵達率，再利用Lagrange’s Method of Multiplier方法，針對GOP-tree中非骨幹部分提出合適的trade-off客製化。最後本研究藉由網路模擬器NS-2(Network Simulater ver. 2)與myEvalvid-NT的實驗架構，做不同效能的評比，並以PSNR值評估所提出之方法的有效性。 / The growing of network popularity, progressing of trasmission technology and development of communication network have facilitated our daily life these years. Wireless network has become a new favor at modern communication market. Among of them, IEEE has started to design and modify specification of WiMAX since 1999, which has been thought to be the solution toward “last mile”. But, there still exist problems such as Doppler effect, blind corner of communication and obstruction of weather condition, which cause the failure of communication. MPEG-4 coding would concern the different significances of distinct types of packets, we should define retransmission strategies for different multimedia packets, respectively. Firstly, we improve the process of ARQ(Auto Repeat reQuest). Secondly, we use MAC-centric design to distinguish multimedia packets and guarantee the arrival rate of packets in the “backbone nodes” of a group of pictures tree. Thirdly, Lagrange’s Method of Multiplier is used to customize the trade-off of “non-backbone node”. In the end, we have performance evaluations by NS-2(Network Simulator ver. 2) and myEvalvid-NT, to verify the efficiency of the proposed method using Peak Signal to Noise Ratio.

聽覺與視覺同為人類最重要的感官。計算式聽覺場景分析(Computation Auditory Scene Analysis, CASA)透過聽覺心理學中對於人耳特性與心理感知的關連性，定義了一個可能的方向，讓電腦聽覺更為貼近人類感知。本研究目的在於應用聽覺心理學之原則，以影像處理與圖型辨識技術，設計音訊增益、切割、描述等對應之處理，透過相似度計算方式實現智慧家庭之環境中的即時音訊分類。 本研究分為三部分，第一部分為音訊處理，將環境中的聲音轉換成電腦可處理與強化之訊號；第二部分透過CASA原則設計影像處理，以冀於影像上達成音訊處理之結果，並以影像特徵加以描述音訊事件；第三部分定義影像特徵之距離，以K個最近鄰點(K-Nearest Neighbor, KNN)技術針對智慧家庭環境常見之音訊事件，實現即時辨識與分類。實驗結果顯示本論文所提出的音訊分類方法有著不錯的效果，對八種家庭環境常見的聲音辨識正確率可達80-90%，而在雜訊或其他聲音干擾的情況下，辨識結果也維持在70%左右。 / Human receive sounds such as language and music through audition. Therefore, audition and vision are viewed as the two most important aspects of human perception. Computational auditory scene analysis (CASA) defined a possible direction to close the gap between computerized audition and human perception using the correlation between features of ears and mental perception in psychology of hearing. In this research, we develop and integrate methods for real-time streaming audio classification based on the principles of psychology of hearing as well as techniques in pattern recognition. There are three major parts in this research. The first is audio processing, translating sounds into information that can be enhanced by computers; the second part uses the principles of CASA to design a framework for audio signal description and event detection by means of computer vision and image processing techniques; the third part defines the distance of image feature vectors and uses K-Nearest Neighbor (KNN) classifier to accomplish audio recognition and classification in real-time. Experimental results show that the proposed approach is quite effective, achieving an overall recognition rate of 80-90% for 8 types of audio input. The performance degrades only slightly in the presence of noise and other interferences.

資料串流探勘是一個重要的研究領域，因為在現實中有許多重要的資料以串流的形式產生或被收集，金融市場的資料常常是一種資料串流，而通常這類型資料的本質是變動性大的。在這篇論文中我們運應了資料串流探勘的技術去預測台灣加權指數期貨的漲跌。對機器而言，預測期貨這種資料串流並不容易，而困難度跟概念飄移的種類與程度或頻率有關。概念飄移表示資料的潛在分布改變，這造成預測的準確率會急遽下降，因此我們專注在如何處理概念飄移。首先我們根據實驗的結果推測台灣加權指數期貨可能存在高頻率的概念飄移。另外實驗結果指出，使用偵測概念飄移的演算法可以大幅改善預測的準確率，甚至對於原本表現不好的演算法都能有顯著的改善。在這篇論文中我們亦整理出專門處理各類概念飄移的演算法。此外，我們提出了一個多分類器演算法，有助於偵測「重複發生」類別的概念飄移。該演算法相比改進之前，其最大的特色在於不需要使用者設定每個子分類器的樣本數，而該樣本數是影響演算法的關鍵之一。 / Data stream mining is an important research field, because data is usually generated and collected in a form of a stream in many cases in the real world. Financial market data is such an example. It is intrinsically dynamic and usually generated in a sequential manner. In this thesis, we apply data stream mining techniques to the prediction of Taiwan Stock Exchange Capitalization Weighted Stock Index Futures or TAIEX Futures. Our goal is to predict the rising or falling of the futures. The prediction is difficult and the difficulty is associated with concept drift, which indicates changes in the underlying data distribution. Therefore, we focus on concept drift handling. We first show that concept drift occurs frequently in the TAIEX Futures data by referring to the results from an empirical study. In addition, the results indicate that a concept drift detection method can improve the accuracy of the prediction even when it is used with a data stream mining algorithm that does not perform well. Next, we explore methods that can help us identify the types of concept drift. The experimental results indicate that sudden and reoccurring concept drift exist in the TAIEX Futures data. Moreover, we propose an ensemble based algorithm for reoccurring concept drift. The most characteristic feature of the proposed algorithm is that it can adaptively determine the chunk size, which is an important parameter for other concept drift handling algorithms.

本文分析近年盛行的電子遊戲實況活動。從分心、不專注於電玩的現象開始，本文以「如何玩」這個提問來引導論證「嬉玩」與「遊戲」這組概念在分析上的效力，藉此，本文論證了電玩實況活動中的心智狀態與活動是游移在電玩活動與嬉鬧互動，在嚴肅遊戲與嬉戲玩耍之間游移，這樣的分神狀態之中也產生了有樂趣、具有實效的遊戲性。 從技術架構的觀點來看，以即時串流的技術為基礎，電玩實況活動結合了即時傳輸與即時互動。使用者所獲致的遊戲聆賞經驗以及互動是即時且與他人同步，便也構成了網路媒介之下的共時經驗，實況中以電玩活動為對象的起鬨也便具共在的實感。本文從聊天室起鬨、技術戲耍挪用等現象中論證了基於遊戲性旨趣的共謀嬉玩。嘲諷、干擾的對抗性是為了製造分神的條件，從中產生張力並獲致遊戲性，而包括實況主在內的所有參與者，皆是在這樣的分神狀態中嬉玩，維繫歡騰的共感情緒。 電子遊戲具有將遊戲性限定在其中的封閉性質，也因此對於電玩的遊戲經驗多有私密、個人的想像，即時串流的電玩實況活動便是打開了這樣的封閉性質。透過網路媒介將人匯聚在遊戲活動周圍，不僅共享了電玩活動本身的樂趣，也在即時串流之下共時的互動跟聆賞經驗中以遊戲為對象群聚嬉戲。這樣的網路活動之所以盛行，顯示了人對遊戲性的需求不僅是來自遊戲中，也來自與他人玩在一起的連結共感，電玩實況便是實現了這樣的需求。 / Taking the prevailing "video game live streaming" activities as research object, this thesis takes "play" and "game" as a set of core concepts, and begins the exploration into their conceptual effect. Setting out the arguments with "How to Play" question, this thesis concludes that the mentality and activities in video game live streaming are in an "in-between" condition. Between video game activity and playful disturbance, seriousness and playfulness, there are gameplay with actual effect. Taking the technical conditions into consideration, video game live streaming consists of live media transportation and live interaction. Users' experiences synchronize with each other, thus contribute to the "togetherness" mediated through the Internet, and also the carnivalistic interactions and disturbance in the live channel. From the fuss and disturbance in the chatroom to the appropriation of streaming "plugins", this thesis argues that these actions conducted by streamer and users contribute to the "distractive" scenario, and the conducts are all based on "the interest of play". Different from serious and immersive mentality which is deemed as the fundamental of playing and gaming, the gameplay in live stream is based on distraction, which is the core condition that brings tension and thus playfulness. All the users in video game live streaming, the streamer included, are connected and forged into a synchronized togetherness by this kind of distractive, carnivalistic playfulness. Digital video games have tributes of enclosure, which require concentration, seriousness and absorption. Video game live streaming opens up this kind of enclosure, and brings people in and around the video game activities. In the live channel, users experience the joy and fun of the game itself together in a synchronized way, and also act on the interest of play, creating distraction and disturbance that bring to playful experiences, and that explains why this kind of Internet activity prevails. This thesis shows that the need of gameplay comes not only from game activities themselves, but also from the desire to "play together". In a digital age, video game live streaming is just the fulfillment of this kind of desire.

近十年來，由於無線網路的普及與人們對於影像串流服務的需求愈高，導致人們迫切需要更好的服務品質。但在IEEE 802.11無線網路中，本身的設計並非針對影像串流來設計，為讓影像串流能在無線網路更有效率，我們必須重新設計適合影像串流的無線網路。本研究首先探討IEEE 802.11 MAC層DCF (Distributed Coordination Function)與802.11e EDCA (Enhanced Distributed Channel Access)機制的潛在問題。由於DCF與EDCA並未特別對影像串流做設計，會導致具有時延(delay time)限制的影像封包等待過久造成失效，卻仍繼續傳送。本研究提出幾個有效方法，改善原本IEEE 802.11無線網路對影像串流傳輸效能不彰的現象。我們將利用跨層設計使MAC層能取得影像串流封包資訊，並改善DCF與EDCA的重傳(retransmission)機制，使用time limit與retry limit混和設計節省不必要的等待時間，並使用single-video multi-level queue改善傳輸效能。最後本研究將利用網路模擬器NS-2 (Network Simulater ver. 2)與影像串流測試實驗架構myEvalvid-NT作不同效能的驗證比較並評估我們所提出方法的有效性。 / Over the past decade, wireless network access and video streaming services have become more popular than ever. People are eager to have better quality of video streaming services over wireless network. However, IEEE 802.11 DCF and IEEE 802.11e EDCA are not specifically designed for video streaming. This leads to the problem of transmitting overdue video packets and thus degrades both the network performance and video quality. In this paper, we propose a hybrid design framework to improve the quality of video streaming. This framework consists of a MAC-centric cross-layer architecture to allow MAC-layer to retrieve video streaming packet information (slice type and transmission deadline), a retransmission mechanism of hybrid retransmission deadline and retry limit to save unnecessary packet waiting time, and a single-video multi-level queue to prioritize I/P/B slice delivery. Simulations show that the proposed methodology outperforms IEEE 802.11e, IEEE 802.11e Timebase and IEEE 802.11e MultiQ in packet loss rate, invalid packet ratio, lost and invalid packet ratio, delay time, jitter, and PSNR.

無線寬頻網路（Mobile Internet Broadband Network）的出現對於無線通訊產業、傳播媒體產業與影音內容產業產生了相當程度的影響，而數位化的科技發展更帶來通訊、傳播及平面媒體產業融合的可能性，無線寬頻影音串流（Mobile Internet Video Streaming）是一架構在此無線通訊媒體匯流後的新產物，透過觀察和分析它的演進發展，可以說明和解釋網路新媒體匯流造成傳統影音產業價值鏈的改變。 吾人將以無線通訊之影音播放技術之演進與發展，以及相對最先發生變化之影音產業經營環境，產生之影響，做產業價值鏈分析研究，進而了解產業經營環境之改變，新的價值創造流程及技術平台的關聯性。並藉由日本NTT DOCOMO之經驗，及對其供應商之觀察，了解台灣產業發展之可能趨勢，及策略建議藍圖。 本研究採P.W. Bane、S.P. Bradley & D.J. Collis (1998)三人提出之寬頻產業五層模式作為分析工具。五層模式分為內容(content)、包裝(package)、傳輸網路(transmission)、操作(manipulation) 及終端設備(terminal)五層架構。主要目的為以整體網路頻寬及技術演進的觀點進行分析五層間價值消長之關係，及整體網路之價值之改變。 我們發現在新的技術導入既有影音市場，由於網路之雙向特性，會產生網路效應及網路外部性，這些地方將產生新的價值所在，而擁有網路外部性的影音操作平台可獲得較高的價值。完整而消費者導向的影音操作平台，將首先累積產業之價值所在，影音操作平台的擁有者將成為產業的領導者，最終將成為標準的制定者。 影音內容的價值獲得來自網路外部性是經由更多人與內容來源(內容提供者)互動，造成下一次消費或其他使用者的外部性以及生產外部性，這樣的外部性是由虛擬連結產生．價值聚集於內容包裝層。 無線寬頻影音操作平台是服務成功的關鍵，有效的整合價值鏈及應用是必須在產業發展前完成，而完整的影音操作平台包含：內容製作壓縮平台、串流平台、訊息平台、及手機之用戶播放平台。 我們發現，新的技術導入市場，需要事先將價值鏈重新定義，整合出可行之新的商業模式，再依據新的價值鏈，新的服務流程去整合新的操作平台，投入服務後，由於是消費者導向的服務設計，可以降低消費者對新科技及新服務的學習門檻及進入障礙，而獲得市場認同。 / “Unlimited boundary & Ubiquitous content” Because of the improving the bandwidth & compression technology of mobile Internet, there are a very extremely industrial convergency in communication, broadcasting, & video audio content industry. There are several new technology including streaming, MPEG, multi media message, 3G which push the whole world going to a new Ubiquitous environment & totally change the old value chain of video audio industry, but we still have no ideal where it should go & what will happen next. We will try to research the technical evolution of video broadcasting which really influence our movie, TV industry. It will change the customer behavior of watching TV, or going to the movie. We especially want to find out where is the new value in the mobile Internet multi media industry. We will use the 5 liars analysis model of broadband industry (P.W. Bane、S.P. Bradley & D.J. Collis (1998))as our basic methodology to find out how the three vertical industries became a new 5 horizontal industries, which are content, package, transmission, manipulation, & terminal. We also want to know how they work internally & externally. We find that the video audio manipulation platform will become the key solution for this value chain, because of its network externality & network effect. The content providers also very important to provide the quality of contents to service the end customers. How to consolidate a new valuable services process & user friendly interface is the big issue here for whom will invest a large of money to creat the new mobile internet portal & new audio vedio manipulation platform. They must think not only the user interface of handset, but also the mechanism of profit sharing between these different providers who never work together in the history.