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排序方式: 共有2284条查询结果,搜索用时 15 毫秒
71.
Hung‐Chieh Lo Po‐Yi Chou Chun‐Chieh Huang Po‐Jui Chen Shih‐Meng Hsu 《Water and Environment Journal》2014,28(3):442-448
Drawing from the lessons learnt from the Fukushima nuclear disaster in Japan, the assessment of subsurface environmental hazard around nuclear power plants has emerged as a critical task. Consequently, aiming to better understand the possible environmental impact of radiation leaks into the groundwater, a prescreening programme was initiated in 2011 by the Taiwanese government. As part of this programme, this study conducted various borehole prospecting techniques to identify in situ hydrogeological characteristics at Chin‐Shan Nuclear Power Plant. Borehole electrical log, sonic log and temperature/conductivity log were conducted to explain the regional lithologic conditions and permeability of the formation. In conjunction with this, the interwell tracer and pumping test was carried out to simultaneously determine the hydraulic parameters. In our opinion, the implementation of such in situ end‐to‐end investigations is essential in interpreting in situ fluid and solute transport dynamics prior to programming any numerical scheme for early warning, vulnerability assessment and regular monitoring of a nuclear power plant site. 相似文献
72.
Shih‐Wen Hsiao Yu‐Ting Hsiao Shih‐Kai Chen Chiao‐Fei Hsu Chun‐Hsing Lee Ya‐Hui Chiang 《Color research and application》2016,41(1):72-84
Light‐emitting diodes (LEDs) have the advantage of controllable light colors and provide the optimal lighting quality against various color attributes required in different environments. However, from the humanized design point of view, beside satisfying physical demands of people, it is also important to achieve satisfaction. With a good match between the LED lighting equipment and ambient colors, the space imagery that complies with psychological needs of human beings can be found. This is expected to become a new market direction for future lighting. In this study, the LED light source feature of adjustable correlated color temperature is used to match wall colors of typical commercial spaces and for the investigation and analysis of the impact of colors of light sources and environments on human beings. The measures of mental and subjective feelings of a group of people under various circumstances have also been investigated. Multivariate analysis of variance has been conducted on three color temperatures of light sources, six wall colors, and measures of five emotion adjectives, and the correlation between these three variables has been further investigated. © 2014 Wiley Periodicals, Inc. Col Res Appl, 41, 72–84, 2016 相似文献
73.
Abstract A textual database deals with retrieval and manipulation of documents. It allows a user to search on‐line complete documents or parts of documents rather than attributes of documents. Resembling a formatted database which uses a data model as its underlying structure, a textual database has to base its development upon a document model. In this paper, a document model, called the ECHO model, is proposed. The ECHO model provides a document representation, called the ECHO structure, for expressing documents and operations on the representation that serve to express queries and manipulations on documents. It has the ability to provide multiple document structures for a document, a flexible search unit for retrieving textual information, and a subrange search on a textual database. In addition, the ECHO structure is relatively easy to maintain. An architecture of a textual database based on the ECHO model is also proposed. In order to improve the query performance, a refined character inversion method, called ARCIM, is proposed as the text‐access method of the Chinese textual database. The ARCIM can retrieve texts faster than a simple inversion method and requires less space overhead. 相似文献
74.
I-Ming Hung Wei-Jen Shih Min-Hsiung Hon Moo-Chin Wang 《International journal of molecular sciences》2012,13(10):13569-13586
In order to obtain the properties of the sintered as-dried calcium phosphate with [Ca]/[P] = 1.50, the characteristics of sintered pellets have been investigated using X-ray diffraction (XRD), inductively coupled plasma-mass spectrometry (ICP-MS), Fourier-transform infrared (FT-IR) spectra, Vickers hardness indentation and scanning electron microscopy (SEM). When the pellet samples were sintered between 700 °C and 1200 °C for 4 h, the hydroxyapatite (Ca10(PO4)6(OH)2, HA) still maintained the major phase, accompanied with the rhenanite (NaCaPO4) as the secondary phase and β-tricalcium phosphate (β-Ca3(PO4)2, β-TCP) as the minor phases. In addition, the HA partially transformed to α-tricalcium phosphate (α-Ca3(PO4)2, α-TCP) and tetracalcium phosphate (Ca4(PO4)2O, TTCP), when the pellet samples were sintered at 1300 °C and 1400 °C, respectively, for 4 h. The maximum density and Vickers Hardness (HV) of sintered pellet samples were 2.85 g/cm3 (90.18% theoretical density (T.D.)) and 407, which appeared at 1200 °C and 900 °C, respectively. 相似文献
75.
A concept of using energy storage material (ESM) or phase change material (PCM) to enhance the heat transfer dissipation by a conventional compact fin-based heat sink is demonstrated. An actual design is developed, fabricated, and tested to demonstrate the heat transfer enhancement. The heat sink is light weight (made with Aluminum) and miniature in size with a total fin length of 26 mm. Test results demonstrated that under a high peak load (4.4 W/cm2) and low duty power cycle (30/55 on/off ratio with a period of 85 sec), the peak temperature at the heating surface with the ESM/PCM heat sink is 5°C lower than that of a conventional heat sink. At the tip of the fin, the peak temperature with the ESM/PCM heat sink is 3°C lower than that of a conventional heat sink. When the external heat transfer coefficient increases (with increase air velocity), the impact of the PCM/ESM on the heat transfer performance is less. A numerical model, based on COMSOL, is developed to provide a theoretical understanding of the experimental observation. 相似文献
76.
C. C. Li C. K. Chung W. L. Shih C. R. Kao 《Metallurgical and Materials Transactions A》2014,45(5):2343-2346
Experiments are carried out to measure the volume shrinkage during solid-state reaction in micro-joints for three-dimensional integrated circuit applications. Surface profilometer is employed to measure the volume shrinkage for the reaction between Ni and Sn. The shrinkage is correlated with the microstructural evolution during the reaction. It is found that the volume shrinkage is released through both joint height reduction and void formation. The resulting internal stress and the void formation might post potential reliability issues. 相似文献
77.
Shih‐Min Chang Erwin F. Rodríguez Tolava Yao‐Jhen Yang Hsin‐Chieh Li Rung‐Chuan Lee Nae‐Lih Wu Cheng‐Che Hsu 《Journal of the American Ceramic Society》2014,97(3):708-712
A one‐step process to fabricate crystalline Li4Ti5O12(LTO) particles directly from solution using an atmospheric pressure plasma jet (APPJ) is reported. This process uses Ti and Li ions‐containing salt solutions as the precursor, which is ultrasonically nebulized and then transported to the downstream of the APPJ using a carrier gas. With an extremely short contact time (<0.1 s) between the precursor droplets and the plasma jet, crystalline LTO can be fabricated in one step without additional rinse and postannealing steps. The LTO particle size can be effectively controlled using a preheater, the precursor solution composition and concentration, and the carrier gas flow rate. By properly adjusting the operating condition, particles of diameters from 100 nm to few μm with various morphologies can be obtained. When used as an electrode material, the resulting LTO powders fabricated under selected conditions show specific capacities over 100 mAh/g even at 50 C rate. 相似文献
78.
Consumer behavior is complicated. In the cosmetic market, personal intuition and fashion trends for color selection are guidelines for consumers. A systematic method for female facial skin‐color classification and an application in the makeup market are proposed in this study. In this article, face recognition with a large number of images is first discussed. Then, an innovative method to capture color at selected points is presented and complexion‐aggregated analysis is performed. This innovative method is an extension of face‐recognition theory. Images in RGB format are converted to CIELAB format during data collection and then Fuzzy C‐means theory is used to cluster and group the data. The results are classified and grouped in Lab value and RGB index. Two programs are created. The first program, “FaceRGB,” captures color automatically from images. The second program, “ColorFCM,” clusters and groups the skin‐color information. The results can be used to assist an expert system in the selection of customized colors during makeup and new‐product development. 相似文献
79.
Abstract The effects of buoyancy forces on the laminar boundary layer flow and heat transfer along vertically moving cylinders are analyzed for the cases of prescribed surface temperature and prescribed wall heat flux in power of streamwise distance. Local similarity solutions are obtained to show the effects of buoyancy parameters and the transverse curvature of the cylinder on the surface friction and heat transfer rate. 相似文献
80.
Jian-Yu Shih Yen-Chi Chen Chih-Hung Chiu Chung-Lun Lo Chi-Chung Chang Kuan-Neng Chen 《Nanoscale research letters》2014,9(1):541
This paper presents one wafer level packaging approach of quartz resonator based on through-silicon via (TSV) interposer with metal or polymer bonding sealing of frequency components. The proposed silicon-based package of quartz resonator adopts several three-dimensional (3D) core technologies, such as Cu TSVs, sealing bonding, and wafer thinning. It is different from conventional quartz resonator using ceramic-based package. With evaluation of mechanical structure design and package performances, this quartz resonator with advanced silicon-based package shows great manufacturability and excellent performance to replace traditional metal lid with ceramic-based interposer fabrication approach. 相似文献