Browsing by Issue Date, starting with "2008-12-10"

Now showing 1 - 20 of 53896

Efficient high-peak-power diode-pumped actively Q-switched Nd:YAG/YVO4 intracavity Raman laser
(2008-12-10)
Su, Kuan-Wei
;
Chang, Ya-Ting
;
Chen, Yung-Fu
;
電子物理學系
;
Department of Electrophysics
An undoped YVO4 crystal is employed to achieve efficient stimulated Raman scattering conversion in a diode-pumped actively Q-switched Nd:YAG laser. With an incident pump power of 16.2 W, an 1176 nm first Stokes average output power of 3.0 W was generated at a pulse repetition rate of 50 kHz, corresponding to an optical-to-optical conversion efficiency of 18.3%. Moreover, the maximum optical-to-optical conversion efficiency of 21.3% was found at 20 kHz. The maximum pulse energy is higher than 83 mu J at both 20 and 30 kHz. With an incident pump power of 7.6W, the underestimated peak power of 43.5 kW was demonstrated at 20 kHz with mode-locked modulation. (c) 2008 Optical Society of America
Method for determining full-field absolute phases in the common-path heterodyne interferometer with an electro-optic modulator
(2008-12-10)
Chen, Yen-Liang
;
Su, Der-Chin
;
光電工程學系
;
Department of Photonics
When a sawtooth voltage signal with the amplitude lower than its half-wave voltage is applied to drive an electro-optic modulator, the interference signals become a group of periodic sinusoidal segments. A new algorithm is proposed to modify these segments to an associated continuous sinusoidal wave, and then its initial phase can be determined. Subtracting the characteristic phase of the modulator from the initial phase, the absolute phase can be obtained. This technique is applied to all pixels, and full-field absolute phase measurements can be achieved. The validity of this method is demonstrated. (c) 2008 Optical Society of America.
Efficient high-peak-power diode-pumped actively Q-switched Nd:YAG/YVO(4) intracavity Raman laser
(2008-12-10)
Su, Kuan-Wei
;
Chang, Ya-Ting
;
Chen, Yung-Fu
;
電子物理學系
;
Department of Electrophysics
An undoped YVO(4) crystal is employed to achieve efficient stimulated Raman scattering conversion in a diode-pumped actively Q-switched Nd:YAG laser. With an incident pump power of 16.2 W, an 1176 nm first Stokes average output power of 3.0 W was generated at a pulse repetition rate of 50 kHz, corresponding to an optical-to-optical conversion efficiency of 18.3%. Moreover, the maximum optical-to-optical conversion efficiency of 21.3% was found at 20 kHz. The maximum pulse energy is higher than 83 mu J at both 20 and 30 kHz. With an incident pump power of 7.6W, the underestimated peak power of 43.5 kW was demonstrated at 20 kHz with mode-locked modulation. (c) 2008 Optical Society of America
Detection of gold nanoparticles using an immunoglobulin-coated piezoelectric sensor
(2008-12-10)
Chen, Yu-Shiun
;
Hung, Yao-Ching
;
Chen, Kaochao
;
Huang, Guewha Steven
;
材料科學與工程學系
Since the existence of nanoparticles in our environment has already attracted considerable attention due to their possible toxic impact on biological systems, the field detection of nanoparticles is becoming a technology that will be much in need. We have constructed a piezoelectric sensor with an antibody-coated electrode. The antiserum can bind gold nanoparticles with a high degree of selectivity and sensitivity. The biosensor thus constructed can detect 4, 5, or 6 nm gold nanoparticles (GNPs) depending on the coated antiserum. The sensitivity for the detection of 5 nm GNPs was 10.3 +/- 0.9 ng Hz(-1), with the low limit of detection at 5.5 ng. A quartz crystal microbalance (QCM) sensor was capable of detecting GNPs and other types of nanoparticle, such as ZnO, or Fe(3)O(4). The current study provides, for the first time, a platform for detecting nanoparticles in a convenient, economical manner.
Direct numerical simulation of wind-wave generation processes
(2008-12-10)
Lin, Mei-Ying
;
Moeng, Chin-Hoh
;
Tsai, Wu-Ting
;
Sullivan, Peter P.
;
Belcher, Stephen E.
An air-water coupled model is developed to investigate wind-wave generation processes at low wind speed where the surface wind stress is about 0.089 dyn cm(-2) and the associated surface friction velocities of the air and the water are u(a)(*) similar to 8.6 cm s(-1) and u(w)* similar to 0.3 cm s(-1), respectively. The air-water coupled model satisfies continuity of velocity and stress at the interface simultaneously, and hence can capture the interaction between air and water motions. Our simulations show that the wavelength of the fastest growing waves agrees with laboratory measurements (lambda similar to 8-12 cm) and the wave growth consists of linear and exponential growth stages as suggested by theoretical and experimental studies. Constrained by the linearization of the interfacial boundary conditions, we perform simulations only for a short time period, about 70 s; the maximum wave slope of our simulated waves is ak similar to 0.01 and the associated wave age is c/u(a)*similar to 5, which is a slow-moving wave. The effects of waves on turbulence statistics above and below the interface are examined. Sensitivity tests are carried out to investigate the effects of turbulence in the water, surface tension, and the numerical depth of the air domain. The growth rates of the simulated waves are compared to a previous theory for linear growth and to experimental data and previous simulations that used a prescribed wavy surface for exponential growth. In the exponential growth stage, some of the simulated wave growth rates are comparable to previous studies, but some are about 2-3 times larger than previous studies. In the linear growth stage, the simulated wave growth rates for these four simulation runs are about 1-2 times larger than previously predicted. In qualitative agreement with previous theories for slow-moving waves, the mechanisms for the energy transfer from wind to waves in our simulations are mainly from turbulence-induced pressure fluctuations in the linear growth stage and due to the in-phase relationship between wave slope and wave-induced pressure fluctuations in the exponential growth stage.
Electron emissions in InAs quantum dots containing a nitrogen incorporation induced defect state: the influence of thermal annealing
(2008-12-10)
Chen, J. F.
;
Yu, C. C.
;
Yang, C. H.
;
電子物理學系
;
Department of Electrophysics
With the incorporation of nitrogen (N) into InAs quantum dots (QDs), the carrier distribution near the QD displays electron emissions from a localized N-induced defect state at 0.34 eV and a weak emission at 0.15 eV from the QD. This defect state causes drastic carrier depletion in the neighboring GaAs bottom layer near the QD, which can effectively suppress tunneling emission for the QD excited states. As a result, electrons escape from the QD ground state through thermal emission to near the GaAs conduction band, rather than through thermal emission to the QD first excited state and a subsequent tunneling to the GaAs conduction band, as observed in InAs QDs without N incorporation. Thermal annealing can weaken the defect emission and enhance the QD emission, suggesting a removal of the defect state and a recovery of carriers in the QD. Increasing annealing temperature can significantly decrease the emission time and energy of the QD emission, which is explained by a weakening of tunneling suppression due to the removal of the defect state.
Method for promoting light emission efficiency of LED using nanorods structure
(2008-12-11)
Huang, Hung-Wen
;
Lu, Tien-Chang
;
Chiu, Ching-Hua
;
Kuo, Hao-Chung
;
Wang, Shing-Chung
Method for the light emitting diode (LED) having the nanorods-like structure is provided. The LED employs the nanorods are subsequently formed in a longitudinal direction by the etching method and the PEC method. In addition, the plurality of the nanorods is arranged in an array so that provide the LED having much greater brightness and higher light emission efficiency than the conventional LED.
一體兩面本業與作息
(2008-12-14)
陳碩峰
;
Department of Communication and Technology
;
傳播與科技學系
現今的學生，因過多的外務而生活作息不正常，導致學習的效果差。
《關於跑步我說的其實是……》
(2008-12-14)
楊睿愷
;
Department of Communication and Technology
;
傳播與科技學系
村上春樹，一個跑步的小說家。關於跑步，他說的其實是一輩子傾身、忠於寫作的人生。雖偶有對於遙遠終點線的存在感到些許不安，但沿途璀麗多樣的景致與堅定不移的心志，才是他在跑步與寫作場景交互遞嬗變遷中，所贏得最為珍貴豐碩的禮物。
紀念　暮水街的三月十一號
(2008-12-14)
黃湘茹
;
Department of Communication and Technology
;
傳播與科技學系
...
由兩個女人　窺看詩人的愛情
(2008-12-14)
陳怡秀
;
Department of Communication and Technology
;
傳播與科技學系
影評
不要把他當動「物」好嗎？
(2008-12-14)
楊純芳
;
Department of Communication and Technology
;
傳播與科技學系
經濟不景氣引發大批棄養潮，台灣各地動物收容所皆呈現「客滿」的狀態，但每天仍有應接不暇的流浪動物。雖然如此，寵物店外的櫥窗依然不時出現「愛狗」人士，看著待價而沽的幼犬，準備給他們一個家。
為了生存《情非得已》
(2008-12-14)
梁素茵
;
Department of Communication and Technology
;
傳播與科技學系
改寫影評
鬼才安德魯　勾勒虛擬真實面
(2008-12-14)
洪效凡
;
Department of Communication and Technology
;
傳播與科技學系
導演兼編劇安德魯‧尼柯，慣於利用制約性空間的題材，向各種社會現象作反思，人活在當下是虛假還是真實？人們崇拜著、渴求著無法觸碰的影像，活在這不可抗拒的規則中，安德魯將這哲學性思考付諸實行，巧妙安排在不同作品裡，看似毫無相關的電影，其實蘊藏著縝密的思維。
堅持自我－閃靈樂團
(2008-12-14)
余建良
;
Department of Communication and Technology
;
傳播與科技學系
閃靈樂團嗯!
第三十七期總編輯的話
(2008-12-14)
林麗珊
;
Department of Communication and Technology
;
傳播與科技學系
總編輯的話
寞。站。
(2008-12-14)
羅兆恆
;
Department of Communication and Technology
;
傳播與科技學系
y
追求環保，你「筷」樂嗎？
(2008-12-14)
黃惠琳
;
Department of Communication and Technology
;
傳播與科技學系
無
交大美食界紅人－豆花阿姨
(2008-12-14)
羅佩雯
;
Department of Communication and Technology
;
傳播與科技學系
從交大二餐搬過來交大女二舍的相思豆花店，有位大大擄獲學生心的阿姨。「嗨～帥哥（美女）今天想吃什麼？」是她的招牌口號！就因為如此親切的招待，和不吝嗇的加料；每周會視天氣情況來推出各種新奇的口味甜品，像是前陣子夯片全台的「海角七號」、消暑養顏聖品「綠豆嘉義人」、天冷來碗「薑汁湯圓」等。如此創新的行銷手法，獲得學生們熱烈的支持與回響。學生們不僅用行動來支持阿姨賣的產品，也大力在部落格、bbs站上幫忙宣傳；用最原始口耳相傳的方式，替相思豆花店打響知名度並建立口碑。本周便訪問到交大美食界的紅人－相思豆花店阿姨。希望藉由這次訪問，可以讓同學們更進一步了解阿姨在生意上的用心，和一些不為人知的生意小撇步！
冬日‧新竹海岸‧不寂寞
(2008-12-14)
吳佳玲
;
Department of Communication and Technology
;
傳播與科技學系
冬日午後，落日餘暉。新竹十七公里海岸邊，落日艷陽，卻勁風懾人，不禁令人蜷縮起身子。放遠望去，屬於夏日的海邊，此時，卻寥寥無幾人，岸邊寂寞。然而，卻因激情的海風觸起浪花朵朵，於是，海面自娛唱起海風歌謠。冬日海岸不是寂寞，至始至終用同一種方式，等待屬於他的夏日。