2010.4
About Instruments Today No. 175
Renewable Energy Technology
Application of a Light Powered Wireless Sensor Network for Providing a Comfortable Environment in a Convenient Store [ 下載 PDF ]
Chih-Sheng Chen, Da-sheng Lee, Ping-Hei Chen
The aims of this study are not only to provide customers a comfortable environment by controlling the temperature and lighting in a shopping area with a wireless sensor network but also to save power consumption. In a Men to Machine, Machine to Men (M2M) platform, a wireless sensor network powered with indoor-lighting is used to collect environmental data of temperature, humidity, and air velocity data. The collected data are transmitted to the platform by using a Radio Frequency Identifi cation (RFID) technique for determining the optimal settings of airconditioning. Before implementing the proposed M2M platform in a convenient store, the indoor Predicted Mean Vote (PMV) of the convenience store is 0–0.5 and the power consumption of air-conditioning is 1.8–2.0 kWh. After implementing the proposed M2M platform in a convenient store, the PMV is kept around 0.4 and the power consumption of air-conditioning system is reduced to a value of 1.2–1.8 kWh. The proposed platform can not only save 15% of power consumption of air-conditioning of the convenient store but also to keep the same comfortable environment of shoppers in the convenient store.
Experience and Evaluation of Wind Energy Measurement Instruments [ 下載 PDF ]
Yi-Chen Li, Yung-Ming Su, Wei-Hsien Lu
Wind power technology is gaining increasing concern recently, and the accurate wind energy assessment can help us select a better site. Therefore, it is no doubt that wind energy observation is a very important technology for site selection. Under this kind of condition, in recent years Industrial Technology Research Institute (ITRI) has established fi ve onshore wind masts and one offshore wind observation station. In addition, ITRI has a portable wind measurement equipment. This article will describe the measurement experience and advantages/disadvantages of the historical measurement system in ITRI. From our measurement experience, the PC based data log is not suitable for the out door estimate system, and it suggests that single chip data log is convenient to the measurement system. On the other hand, the portable SODAR (Sound Detection and Ranging) profi ler can measure wind speed at different altitude at the same time. But, SODAR will easily interfere with the surrounding environment. Besides, during the measurement, SODAR is very noisy. Therefore, the selection of the measurement period and position will be very signifi cance because it is related to the accuracy of data.
Ocean Current Power in the Region around Taiwan [ 下載 PDF ]
Sheng Fong Lin
The ocean current in the sea around Taiwan is a reliable, self-generating, and clean source of energy that should not be overlooked. This article describes the probability distribution of current velocity and the potential spatial distribution of current energy in the region around Taiwan, while introducing recent international developments in ocean current generator technology. By using ocean current generators of low rated speed in accordance with observed and simulated ocean current data, we are in the process of developing ducted turbines that can be used for ocean current power generation in an effort to increase the effi ciency of the generators as well as the economic value of their development and utilization.
Higee Technology Development and Applications [ 下載 PDF ]
Ling-Jung Hsu, Chia-Chang Lin
A novel Higee technology has been developed by the utilization of rotating packed beds, providing an intense contact between gas and liquid under a high gravity, thus leading to a higher gas-liquid mass transfer. This technology is characterized by its high mass transfer efficiency, small equipment size, high process capacity, low energy consumption, and low operating and capital costs. Therefore, this technology has been widely used to distillation, stripping, absorption, ozonation, and nanoparticles synthesis. This article focuses mainly on the principles of this technology. Some research results obtained by Higee Laboratory at Chang Gung University were also given, including VOCs absorption, CO2 absorption, and fabrication and application of nanoparticles.
Deep-UV Excimer-Laser-Induced Photomodifi cation of Hollow Metal Nanoparticles for High-Density Data Storage Systems [ 下載 PDF ]
Dehui Wan, Hsuen-Li Chen, Shao-Chin Tseng
In this paper, we report a new optical data storage method: photomodifi cation of hollow gold nanoparticle (HGN) monolayers induced by one-shot deep-ultraviolet (DUV) KrF laser recording. The short wavelength of the recording DUV laser improved the optical resolution dramatically. We prepared HGNs exhibiting two absorbance regions: a surface plasmon resonance (SPR) peak in the near-infrared (NIR) region and an intrinsic material extinction in the DUV region. A single pulse from a KrF laser heated the HGNs and transformed them from hollow structures to smaller solid spheres. This change in morphology for the HGNs was accompanied by a signifi cant blue shift of the SPR peak. Employing this approach, we demonstrated its patterning ability with a resolving power of a half-micrometer (using a phase mask) and developed a readout method (using a blue-ray laser microscope).
Label-Free Biosensor [ 下載 PDF ]
Chia-Ming Chang, Chia-Yu Li, Chang-Yue Chiang, Lai-Kwan Chau
As compared to conventional bio-detection techniques such as those with fl uorescence and radioactive labelling, label-free biosensors not only avoid the errors due to the labelling procedure but also offer additional advantages such as short analysis time, simple procedure, and capability of real-time monitoring. Furthermore, it is a powerful analytical tool for studies of bio-interaction kinetics, bio-affinity, and concentration of biological species in real samples. This report will introduce the principles of several label-free biosensing techniques that have relatively high market shares today and their commercialized instruments. The techniques to be described will include surface plasmon resonance (SPR), guided mode resonance (GMR), optical interference, and fi ber optic-localized plasmon resonance (FO-LPR) which is developed by our laboratory.
Study on Reshaping Waveforms of THz Time- Domain Spectroscopy with Millimeter Metal Devices [ 下載 PDF ]
Shian-Wen Chang, Tai-Shen Wang, Chun-Jen Weng, Shyh-Shii Pai
This study employs the technique of terahertz (THz) time-domain spectroscopy (TDS) and the emitter is a largeaperture photoconductive antenna. We use millimeter dimensional metal devices to realize the spatial distribution of radiation frequency from THz wave emitter and the transmittance of THz wave depended on the orientation of the polarizing device. The amplitude ratio of 0.2 THz to 0.8 THz increases with the diameter of metal hole and the blocking area with the circular metal plate. In the knife-edge experiment, the high frequency (0.6 THz) peak drop rapidly as covering the center area. Thus the low frequency component is dominant for the emitter and the intensity of high frequency component substantially reduces with the divergence angle. The polarizing device is composed of several commercial copper wires to collocate above a metal hole. THz wave propagates through the polarizing device without signifi cant power loss when the orientation of wires perpendicular to the polarization of THz wave. For the parallel case, the polarizing device exhibits the characteristic of a high-pass fi lter. The transmittance increases with frequency below 0.8 THz and closes to 1 over 0.8 THz. Therefore, the polarizing devices can reshape the THz waveform and provide a convenient means to manipulate the resonance features of THz wave.
Plasma-Assisted Molecular Beam Epitaxy for GaN Growth [ 下載 PDF ]
Wen-Yuan Pang, Ikai Lo, Chia-Ho Hsieh, Yu-Chi Hsu, Ming-Chi Chou
In this article, we introduced radio-frequency plasma-assisted molecular beam epitaxy (PA-MBE) and its application in the growth of III-nitride based semiconductors. We also demonstrated the growth of high quality AlGaN/GaN heterostructures and self-assembling GaN hexagonal micro-scaled disk/pyramid by using the radio-frequency plasma-assisted MBE located at National Sun Yat-sen University.
Near-Perfect Robust Superhydrophobicity [ 下載 PDF ]
Jiann Shieh, Fu Ju Hou, Yan Chen Chen, Hung Min Chen, Shun Po Yang, Chao Chia Cheng, Hsuen Li Chen
We report an air-like 'bed of nails' that supports a drop of water without impalement by fabricating the two-tier superhydrophobic structures comprising two types of nanoscale features: a nanograss that provided a large water contact angle (157°) and nanopillars that reduced the stickiness of the water drop on the nanograss. These nanograsson- nanopillar structures exhibited robust air-like surfaces. For the structure featuring a pillar separation of 5 µm, 99.98% of the surface was composed of air, yet the structure could still support a water droplet subjected to a pressure of 234 Pa. Because of their very low solid fractions and high robustness, these air-like surfaces exhibit near-perfect superhydrophobicity—that is, water contact angles close to 180° and sliding angles close to 0°.
Integrated Opto-Mechanical Analysis of Optical Mirror for Remote Sensing Instrument [ 下載 PDF ]
Yu-Chuan Lin, Long-Jeng Lee, Shenq-Tsong Chang
This article reports the integrated opto-mechanical analysis approach to design, analysis, and optimization of the performance of optical light-weighted mirror subjected to environmental infl uences including static, dynamic and thermal loading. Emphasized is the application of the fi nite element technique to develop practical model for lightweighted mirror, and Zernike polynomials fi tting from thermal and structural response quantities into optical design such as wave-front error are mainly used to fulfi ll this analysis. The numerical result shows that the large lightweight mirror is obtained by this approach and the calculated deformation is below the requirements of optical design.
