*學術英文投稿教學影片 (110) : MathScinet Tutorial
*工程英文問題描述 (93) (上)
Academic publishing news 學術出版新聞
學術英文投稿教學影片 (110) : MathScinet Tutorial
The Center for Measurements Standards, a subsidiary of the Industrial Technology Research Institute, Hsinchu, Taiwan, is currently developing a flow measurement test rig. Our design consultant suggests the use of ABC valve products on some of our mechanical components. The following is a list of items we are interested in purchasing from your company:
1. Item and spec.: “2” N.B. Series 44 ball valve, complete with weld neck to BS 1560 class 600 LB flange & actuator with series 40, size 20 RKA 40. The flanges should have a 165mm O.D. with holes drilled through equally spaced holes with a diameter of 19mm.
2. Item and spec.: Series 44 ball valve 1/4″ BSPP, complete with actuator series 40 size 05 RDA
Accompanying this letter are two figures of the aforementioned valves.We would appreciate it if you could provide a catalogue and price list, at your earliest convenience. If you have a sales agent in Taiwan or elsewhere in the Far East Region, please inform him or her of our intentions. We look forward to doing business with you.
工程英文問題描述 (93) (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 Increasingly larger substrate requirements have spurred advances in semiconductor manufacturing, explaining the increasing importance of the pumping performance of vacuum pumps in etching, chemical vapor deposition (CVD), and physical vapor deposition (PVD) to satisfy ultraclean environment requirements. However, using oil-free backing pumps in combination with the TMP to satisfy ultraclean environment requirements is problematic. The TMP compound includes the addition of a turbodrag section to the conventional TMP stage in the same rotation shaft in order to ensure that the discharge pressure ranges between 7.5 and 15 Torr. Levi (1992) also pioneered the use of hybrid pumps, which uses a variety of impellers without increasing the number of stages on the same axis. Notably, the conventionally adopted TMP uses momentum transfers from high-speed rotating blades to the gas molecules for pumping gas. According to the direction of the pumped fluid to the movement of the moving wall, the TMP is perpendicular to the movement of the moving wall; otherwise, the molecular drag pump (MDP) is parallel. The MDP can operate in the 7.5x-3 Torr-7.5 x-2 Torr at a full pumping speed owing to a high compression ration in the viscous flow regime, which is infeasible for a molecular flow regime. 工程計劃問題 The CVD and etching equipment in the IC industry require superior discharge pressures from the atmosphere to a high-vacuum region. Among the many subsequent design types include those of Becker, Siegbahn, Holwek, and Gaede. Although these designs normally increase either the pumping speed or compression ratio, increasing the pumping speed and compression simultaneously (especially in higher discharge pressures) is problematic owing to the complex transition flow phenomena. Additionally, the processing pressure can not remain constant with a declining pumping performance. 工程計劃問題的量化 A typical TMP typically has many stages for optimizing the pumping speed and compression ratio, resulting in different compression ratios, especially the lower value for light gases. Moreover, the compression ratios are high at discharge pressures lower than 7.5x-3 Torr. However, the pumping speed obviously declines at higher discharge pressures. 工程計劃問題的中心 Ultimately, the pumping performances of TMP lower its efficiency as the distance of blades becomes comparable to the mean free path of gas molecules. 工程計劃需求 Therefore, a vacuum performance system must be developed based on ISO standards with automatic testing and human-machine interface functions.