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四、請針對以下火羽在溫度層化環境下(Plumes in Temperature - StratifiedAmbients)的描述,解讀附圖的物理現象。火災科學 1原文:When a buoyant, turbulent plume rises, it cools by entrainment ofambient air. If the ambient air increases in temperature with height, which isnormal in buildings, and the fire source is weak, the temperature differencebetween the plume and the ambient, which gives the plume buoyancy, mayvanish and actually reverse in sign. Eventually the plume ceases to rise.Figure: Theoretical behavior of centerline plume variables in linearlytemperature-stratified ambients. Curve A: ratio of temperature rises (stratifiedversus unstratified), Curve B: ratio of axial velocities. Curve C: ratio of plumeradii. Curve D: ratio of volumetric species concentrations. Where z: heightabove top of combustible (m) and Zm: maximum vertical penetration of plumefluid in stratified ambient (m)火災科學 2

三、請以史帝芬-波茲曼(Stefan-Boltzmann)公式,說明幅射熱熱傳特性(10 分),並針對設備測試、系統功能及性能設計方面,提出 3 種在防火工程(Fire Safety Engineering)上的運用情境(15 分)。

二、A sinusoidal voltage \( E \sin \omega t \), where \( t \) is time, is passed through a half-wave rectifier that clips the negative portion of the wave. Find the Fourier series of the resulting period function. \[ u(t) = \begin{cases} 0 & \text{if } -L < t < 0 \\ E \sin \omega t & \text{if } 0 < t < L \end{cases} \quad p = 2L = \frac{2\pi}{\omega} \]

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15 製作水合三氯乙醛栓劑時,加入鯨蠟的目的為: (A)幫助藥品溶解 (B)防止成分酸敗 (C)調整成品硬度 (D)製作乳化成品

16 下列何者是最不適當的鑄道放置位置? (A)3/4 牙冠(three-quarter crown)放在舌側面 (B)MOD 嵌體(inlay)放在遠心邊緣嵴(distal marginal ridge) (C)釘台體(pinledge)放在最大肉厚部且與釘子的方向平行 (D)瓷融合金屬冠(porcelain fused to metal crown)放在頰側咬頭(buccal cusp)

10.航空器駕駛員,駕駛航空器飛越禁航區者:(A)處三個月以下有期徒刑 (B)處六個月以下有期徒刑 (C)處二年以下有期徒刑拘役或新台幣40萬元以下罰金 (D)處一年以下有期徒刑

8. The private school mainly serves ______ families who can afford high tuition and extensive extracurricular programs. (A) negligible (B) ubiquitous (C) unsightly (D) affluent

21. If the interest rate on savings increases, (A) Mary will decrease her savings in the work period if the income effect is greater than the substitution effect for her. (B) Mary will increase her savings in the work period if the income effect is greater than the substitution effect for her. (C) Mary will increase her savings in the work period if the substitution effect is greater than the income effect for her. (D) Both a and c are correct.

22. In an imaginary economy, consumers buy only sandwiches and magazines. The fixed basket consists of 20 sandwiches and 30 magazines. In 2006, a sandwich cost $4 and a magazine cost $2. In 2007, a sandwich cost $5. The base year is 2006. If the consumer price index in 2007 was 125, then how much did a magazine cost in 2007? (A) $0.83 (B) $2.25 (C) $2.50 (D) $3.00