http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/156 Tue, 24 Mar 2026 21:14:21 GMT 2026-03-24T21:14:21Z http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/16699 標題: ＮＲ車用網路的安全群播; Reliable Groupcast For NR V2X 作者: Yan-Teng Kuo; 郭彥滕 摘要: 隨著自動駕駛汽車的發展，高可靠性和低延遲的車輛通訊技術變得越來越重要。第三代合作夥伴計劃（3GPP）特別討論新無線（NR）下的邊緣連結（SL）傳輸，目的是滿足低延遲，高可靠性和高流通量的車聯網（V2X）要求。與僅支持廣播方案的長期演進技術（LTE）V2X相比，NR V2X還支持兩種方案：單播和群播。群播方案允許發射機一次與同一群中的多個接收機進行通訊。在本論文中，我們呈現了NR V2X模式2的盲重傳。為了保持傳輸的可靠性，車輛群的大小需要被限制，以避免由於非直視性（NLOS）傳輸而引起的錯誤。並且，為了提高傳輸的可靠性，本文提出了一種優化群接受率的重傳方法，可以使發射機在同一群中分配一個重傳裝置進行重傳。我們設計了一個重傳裝置選擇問題，旨在最大程度地提高NR V2X模式2群播的群接收率（GPRR）。模擬的結果顯示，所提出的重傳方法從GPRR、分組間接收時間（PIR）和可靠性限制下的車輛群大小方面改善了車聯網群播。; With the development of autonomous vehicles, the high reliability and low latency vehicular communication technologies has become more important. The Third Generation Partnership Project (3GPP) specifies the sidelink (SL) transmission based on New Radio (NR) structure, which aims to meet the the low latency, high reliability and high throughout vehicle-to-everything (V2X) requirements. Compared with Long Term Evolution (LTE) V2X which only supports broadcast use cases, NR V2X supports two more scenarios: unicast and groupcast. The groupcast operation allows the transmitter to communicate with multiple receivers in same group at once. In this paper, we present the blind retranmission operation for NR V2X mode 2. To maintain the transmission reliability, the group size for vehicles is restricted to avoid errors due to Non-line-of sight (NLOS) transmission. In order to improve the transmission reliability, this paper proposes a optimized group packet reception ratio retransmission, which allows transmitter to assign a retransmission UE in same group to perform the retransmission. We formulate a retransmission UE selection problem, which aims to maximize the group packet reception ratio (GPRR) for NR V2X mode 2 groupcast. The simulation results show that the proposed retransmission method improves the V2X groupcast in terms of GPRR, packet inter-reception time (PIR) and the available group size. Wed, 01 Jan 2020 00:00:00 GMT http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/16699 2020-01-01T00:00:00Z http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/47422 標題: 鼠籠式風力發電機串聯動態電壓調整器之設計; Design of a Dynamic Voltage Regulator for a Squirrel-Cage Induction Generator 作者: Shiang-Cong Chen; 陳翔琮 摘要: 由於節能減碳的需求，全球正快速發展與綠色能源相關之技術，「風」為一天然、無污染之資源，風力發電的技術與理論便成為綠色能源發展中最重要的方向與目標之一。 風力發電所使用的電機種類型式眾多，其中又以鼠籠式感應機價格較為低廉，可大量量產並安裝在風力資源豐富之地區。但由於鼠籠式感應機缺乏對無效電力控制的能力，當系統發生負載加載、切載或故障時，無法負擔支撐起系統的責任，風力不穩定時，感應機便成為整個系統中電力潮流的汙染源，影響電力品質。 為了改善上述缺點，本論文在鼠籠式感應機上串聯動態電壓調整器，控制發電機流入系統匯流排之電力潮流，改善電力品質。並在系統發生加載、切載或故障時，進行適當的補償，穩定整個系統電壓。 本論文利用MATLAB○R/Simulink/SimPowerSystems軟體模擬電力系統負載變動以及風速變動時，發電機及負載端電壓。由模擬結果發現動態電壓調整器能有效穩定發電機及負載電壓。諧波失真也都能符合台電諧波管制標準。; To Reduce emission, much effort has been devoted to the development of green energy techniques. Among the various types of green energy generations, wind energy conversion is studied in thesis. Squirrel-cage induction generators have been widely employed for wind energy conversion due to their low costs and high reliability. However, the squirrel-cage induction generators are not capable of providing voltage regulation due to the lack of rotor excitation. To improve the reactive power support and voltage regulation of a squirrel-cage induction generator, a dynamic voltage regulator（DVR） is designed in this thesis. Through the generation or absorption of reactive power, the DVR is capable of stabilizing the generator terminal voltage and the load voltage when the system is subject to load changes or wind speed variations. The effectiveness of the proposed DVR is demonstrated by computer simulations using MATLAB○R/Simulink/SimPowerSystems. Fri, 01 Jan 2010 00:00:00 GMT http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/47422 2010-01-01T00:00:00Z http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/43767 標題: 點棒可視圖的厚度最佳漸近上界; Asymptotically Optimal Thickness Bounds of Generalized Bar Visibility Graphs 作者: Yen-Peng Sung; 宋彥朋 摘要: Given a set of disjoint horizontal line segments (call bars), d(b1, b2) of two bars b1 and b2 is the minimum number of the other bars that the vertical line segments whose endpoints are at b1 and b2 passing through. A graph G is a bar k-visibility graph if G can be represented as a set of disjoint bars such that any two vertices are adjacent in G if and only if d(u, v) ≤ k, where u and v are the associated bars with those vertices. A graph G is a semi bar k-visibility graph if G can be represented as a set of disjoint bars whose left endpoints have the same x-coordinates such that any two vertices are adjacent in G if and only if d(u, v) ≤ k, where u and v are the associated bars with those vertices. The thickness of G is the minimum number of planar subgraphs whose union is G. Dean et al. gave the best previously known upper bound 3k(6k + 1) on the thickness of bar k-visibility graphs. Hartke et al. proved that the largest complete graph in bar k-visibility graphs is K_4k+4, so the upper bound on the thickness of bar kvisibility graphs is at least ⌈(2k +3)/3⌉. Felsner and Massow gave an upper bound on the thickness of semi bar 1-visibility graphs. Felsner and Massow proved that K_2k+3 is the largest complete graph in semi bar k visibility graphs, so the upper bound on the thickness of semi bar k visibility graphs is at least ⌈(2k + 5)/6⌉. We reduce the upper bound to 3k + 3 on the thickness of bar k-visibility graphs, and give an upper bound 2k for semi bar k-visibility graphs. Thu, 01 Jan 2009 00:00:00 GMT http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/43767 2009-01-01T00:00:00Z http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/33582 標題: 點對點網路的多人虛擬世界負載平衡機制; Load-balancing for Peer-to-peer Networked Virtual Environment 作者: Chin-Hua Sun; 孫錦驊 摘要: 點對點網路允許每一台電腦直接連結到其他電腦做溝通。現在最常見的應用是檔案分享。不過，分散式運算才是點對點網路的主要功能。 網路遊戲是現在最流行的趨勢，而目前市面上看得到的多人角色扮演遊戲(MMORPG, Massive Multi-user Online Role Playing Game) 都是採用傳統的主從式架構。這樣的架構有下列幾個壞處：伺服器的建置成本高；伺服器一旦出問題就會導致整個遊戲無法進行；提供遊戲的廠商需提供數個伺服器以容納更多的使用者。但是，連接到不同伺服器的玩家其實並不在相同的環境中。 本論文是針對MMORPG，提出一個點對點的架構，並且加入動態狀態資訊分配 (DSID, Dynamic Status Information Distribution) 來解決上述主從式架構下所產生的問題，以期能做出一個建置成本低並且富有彈性的遊戲架構，同時也允許所有的使用者都能夠在同樣的一個環境中進行互動。; The peer-to-peer network allows each computer to connect to other computers directly. Its most popular application today is file sharing, but distributed computing is the main function of peer-to-peer network. The trend of games is online games. Most MMORPGs (Massive Multi-user Online Role Playing Games) we can see today are based on client-server architecture. This causes some disadvantages as follows: the server is very expensive and the failure of the server fails the whole game. Besides, the vendor of a game need to provide several servers to allow more players playing at the same time, but players connect to different servers are in the different virtual environments. This thesis provides a peer-to-peer architecture with dynamic status information distribution (DSID) mechanism for MMORPG to address the issues occurred in the client-server architecture. We hope to construct a low-cost and flexible architecture that allows all players to interact to each other in the same virtual environment. Sun, 01 Jan 2006 00:00:00 GMT http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/33582 2006-01-01T00:00:00Z