* 如何保持一個專業的線上陳述 (PART A)
* 如何參與視訊會議 (PART B)
* 助研究思考及寫作的背景音樂 (295)
* 住宿/交通工具之安排 (國外訪問) (有效撰寫專業英文電子郵件) (1 of 3)
* 工程英文問題描述 (45) (上)
Academic publishing news 學術出版新聞
如何保持一個專業的線上陳述 (PART A)
如何參與視訊會議 (PART B)
I would like to make a hotel reservation for three single rooms from March 19 to March 22 (four nights), and another single room from March 21 to March 22 (two nights). My colleagues and I will arrive at 8 p.m. on March 19, and will be registered under the names of Mr. Chang, Mrs. Wu, Mr. Lin (March 19 to March 22), and Ms. Chu (March 21 to March 22).
Your prompt reply as to whether you can accomodate us would be most appreciated. Credit card information is provided as follows.
Awaiting your reply, thanks.
工程英文問題描述 (45) (上)
* 工程提案建構 : 你工程提案的主題是什麼? 你的讀者可以明瞭工程提案的內容嗎?
* 工程問題 : 你的工程提案裡有你試著要解決或是想更進一步瞭解的問題嗎?
* 工程問題的量化 : 你要如何量化問題來讓你的讀者明白之前文獻研究所遇到的量化限制 ?
* 工程問題的中心 : 如果問題沒被解決或是充分瞭解, 這對工程提案的讀者會有多大的負面衝擊?
* 工程計劃需求 : 根據以上問題,最迫切的計劃需求是什麼?
工程計劃建構 PONs play an increasingly significant role in fiber to the x networks, e.g., fiber to the home (FTTH) and fiber to the building (FTTB). A PON specified by G.983.1 comprises an optical line terminal (OLT) connected to multiple optical network terminals (ONTs) in a point-to-multi-point network. A PON network is characterized by its ability to share upstream bandwidth between OLT and ONTs. The bandwidth between OLT and ONTs. The OLT is responsible for allocating bandwidth to the ONTs on traffic contracts. The OLT should devise a dynamic bandwidth allocation (DBA) method to allocate bandwidth dynamically, thus responding effectively to the dynamic changes in traffic demand for vaious ONTs to the network resources efficiently. 工程計劃問題 However, the conventional DBA is based on queue-status reports (SR) sent by ONTs to OLT periodically. The grant scheduler at the OLT defines a granting cycle W. During each W period, the OLT solicits the queue-status reports from ONTs; the ONTs respond with queue-status reports; and, then, the grant scheduler processes these reports and assigns bandwidth for the next W period. The SR delay time, OLT processing time, and PON round-trip time determine the minimal response time. During this period, the queue status changes, often causing SR-DBA to fall below optimal accuracy. In addition to bandwidth efficiency, SR-DBA deployment heavily depends on interoperability between OLT and ONT systems. Specifically, the complexity of ONTs increases due to the higher real-time constraints and additional circuitry required to support queue-status reports. 工程計劃問題的量化 For instance, SR-DBA is inefficient under varying traffic conditions. For instance, the overall bandwidth utilization remains under 80% and the packet delay usually exceeds 4 ms. SR-DBA also implies high buffer requirements over 4 MB and a high packet loss ratio exceeding 5%. 工程計劃問題的中心 SR-DBA is inefficient for FTTH, creating a situation in which inefficient bandwidth utilization expends a considerable amount of investment in PON networks. Additional resources are necessary to achieve the required bandwidth. Additionally, delay-sensitive services such as voice or interactive services cannot comply with standard requirements under a high packet delay. Moreover, users can not wait for a response from the peer for a long delay time. High buffer requirements also imply high overhead costs for a service provider and, ultimately, high subscription charges for users. In sum, a high packet loss cannot satisfy the service level agreement and deteriorate the quality of several services such as in video and FTP. 工程計劃需求 Therefore, a predictive DBA method based on pseudo status report from ONTs must be developed to increase the DBA efficiency.