Microfluidic on-chip fluorescence-activated interface control system     

Haiwang L  Nguyen NT  Wong TN  Ng SL 《Biomicrofluidics》2010,4(4):44109

A microfluidic dynamic fluorescence-activated interface control system was developed for lab-on-a-chip applications. The system consists of a straight rectangular microchannel, a fluorescence excitation source, a detection sensor, a signal conversion circuit, and a high-voltage feedback system. Aqueous NaCl as conducting fluid and aqueous glycerol as nonconducting fluid were introduced to flow side by side into the straight rectangular microchannel. Fluorescent dye was added to the aqueous NaCl to work as a signal representing the interface position. Automatic control of the liquid interface was achieved by controlling the electroosmotic effect that exists only in the conducting fluid using a high-voltage feedback system. A LABVIEW program was developed to control the output of high-voltage power supply according the actual interface position, and then the interface position is modified as the output of high-voltage power supply. At last, the interface can be moved to the desired position automatically using this feedback system. The results show that the system presented in this paper can control an arbitrary interface location in real time. The effects of viscosity ratio, flow rates, and polarity of electric field were discussed. This technique can be extended to switch the sample flow and droplets automatically.  相似文献   

A practitioner's guide for designing performance support systems     

Frank Nguyen  Craig A. Woll 《Performance Improvement》2006,45(9):37-45

  相似文献   

What you already know does matter: Expertise and electronic performance support systems     

Frank Nguyen 《Performance Improvement》2006,45(4):9-12

  相似文献   

聋生劳动技术与职业技能培训研究报告     

张庆玲  陈军  黄观颖 《中国特殊教育》2000,(1)

厦门市特殊教育学校在义务教育中、高年级阶段开展了聋生劳动技术和职业教育试验研究。结果表明 :准备式就业教育模式不但在理论上是可行的 ,而且在实际运用中取得了丰硕的成果 ,并对聋生毕业后的就业产生了积极的有益的影响  相似文献   

Mobile teachers,teacher identity and international schooling     

Thuong Nguyen 《师资教育杂志》2017,43(5):635-637

  相似文献   

Multilingual opinion mining on YouTube – A convolutional N-gram BiLSTM word embedding     

Huy Tien Nguyen  Minh Le Nguyen 《Information processing & management》2018,54(3):451-462

Opinion mining in a multilingual and multi-domain environment as YouTube requires models to be robust across domains as well as languages, and not to rely on linguistic resources (e.g. syntactic parsers, POS-taggers, pre-defined dictionaries) which are not always available in many languages. In this work, we i) proposed a convolutional N-gram BiLSTM (CoNBiLSTM) word embedding which represents a word with semantic and contextual information in short and long distance periods; ii) applied CoNBiLSTM word embedding for predicting the type of a comment, its polarity sentiment (positive, neutral or negative) and whether the sentiment is directed toward the product or video; iii) evaluated the efficiency of our model on the SenTube dataset, which contains comments from two domains (i.e. automobile, tablet) and two languages (i.e. English, Italian). According to the experimental results, CoNBiLSTM generally outperforms the approach using SVM with shallow syntactic structures (STRUCT) – the current state-of-the-art sentiment analysis on the SenTube dataset. In addition, our model achieves more robustness across domains than the STRUCT (e.g. 7.47% of the difference in performance between the two domains for our model vs. 18.8% for the STRUCT)  相似文献   

Intention of students in less developed cities in China to opt for undergraduate education abroad: Does this vary as their perceptions of the attractions of overseas study change?     

Fan-sing Hung 《International Journal of Educational Development》2010

This study is based on a survey in 2007 of 12,961 senior secondary final year students in seven major cities in China, and shows that students in less developed cities manifest a stronger intention to study abroad than students in better off cities, controlling for students’ other demographic characteristics and their major perceived attractions of study abroad. The intention to study abroad of students in less developed cities becomes increasingly lower than the intention of students in better off cities for every unit increase in the perceived attraction of better quality instruction if the students expect to fund their overseas studies by self-financing or loans.  相似文献   

Design of a long range nano-scale resolution mechanism     

Shuo Hung CHANG  Jen Bon LEE 《浙江大学学报(A卷英文版)》2010,11(4):250-254

This paper presents the development of a coarse-fine dual precision positioning stage to achieve long travel range and high accuracy. The fine stage is arranged in series with a coarse stage. The key in the fine stage design is the choice of a toggle mechanism for a tight mechanical loop with high stiffness and compactness. We designed the toggle mechanism for reduction of the displacement to suppress signal noises, The performance of the coarse and fine stages was verified with an optical encoder and capacitive sensor, respectively. The measurement results show that the dual mechanism has a travel range of 1 mm and resolution of 30 nm.  相似文献   

Examining the practice of a reading-to-speak test task: anxiety and experience of EFL students     

Heng-Tsung Danny Huang  Shao-Ting Alan Hung 《Asia Pacific Education Review》2010,11(2):235-242

In the literature, little research has hitherto been conducted to examine the implementation of integrated speaking test tasks. This study, in response, set out to compare the anxiety induced by a reading-to-speak task and the anxiety produced by a speaking-only task and to explore students’ experiences of taking the reading-to-speak task. Forty-seven Taiwanese EFL learners completed a reading-to-speak task and a speaking-only task, filled out a state anxiety inventory twice, and responded to an open-ended questionnaire. The paired t-test revealed that the reading-to-speak task produced a statistically comparable degree of anxiety as the speaking-only task, possibly owing to the additional anxiety inflicted by its reading component. The qualitative analysis disclosed that students preferred the reading-to-speak task to the speaking-only task, even though it provoked additional anxiety, featured additional challenges, and entailed different response strategies. In light of these findings, implications are proposed for oral assessment research and EFL oral assessment practices.  相似文献   

Effect of slippage on the thermocapillary migration of a small droplet     

Nguyen HB  Chen JC 《Biomicrofluidics》2012,6(1):12809-1280913

We conduct a numerical investigation and analytical analysis of the effect of slippage on the thermocapillary migration of a small liquid droplet on a horizontal solid surface. The finite element method is employed to solve the Navier-Stokes equations coupled with the energy equation. The effect of the slip behavior on the droplet migration is determined by using the Navier slip condition at the solid-liquid boundary. The results indicate that the dynamic contact angles and the contact angle hysteresis of the droplet are strictly correlated to the slip coefficient. The enhancement of the slip length leads to an increase in the droplet migration velocity due to the enhancement of the net momentum of thermocapillary convection vortices inside the droplet. A larger contact angle leads to an increase in the migration velocity which in turn enlarges the rate of the droplet migration velocity to the slip length. There is good agreement between the analytical and the numerical results when the dynamic contact angle utilizes in the analytical approach obtained from the results of the numerical computation, and the static contact angle is smaller than 50°.  相似文献