DSpace collection: 期刊論文

Wire electrochemical discharge machining (WECDM) of quartz glass with titrated electrolyte flow

title: Wire electrochemical discharge machining (WECDM) of quartz glass with titrated electrolyte flow abstract: 摘要： Electrochemical discharge machining (ECDM) is a promising technique with great potential for application to machining non-conductive brittle materials. In this study, wire electrochemical discharge machining (WECDM) was applied to processing quartz glass with electrolyte supplied in titrated flow. During WECDM, under surface tension and gravity, the electrolyte flows down in droplets, over the graphite auxiliary electrode and brass wire, producing oxygen and hydrogen bubbles, respectively. The fluid inside the droplet forms eddies on the two sides of the quartz, removing chips and electrolysis resultants. Rapid replenishment of electrolyte to constant concentration can ensure even distribution of current density and a stable insulation gas film can thus be formed. Experimental results show that quartz glass processed by WECDM with titrated electrolyte flow yielded long straight slits of small mean width. In addition, with the electrolyte supplied in droplets, less electrolyte is consumed in the process. The proposed droplet titration approach to WECDM of quartz glass incurs less cost and pollution, making it both cost effective and environmental friendly. •This study resolved the difficulty of electrolyte circulation in the machining area.•Stirring effect was achieved by coalescent growth of oxygen and hydrogen bubbles.•Pulse current produced by titration process enhanced machining accuracy and efficacy.•Consuming less electrolyte and localized machining saved cost and reduced pollution. 出版者： Elsevier Ltd 出版日期： 2013-09-01 出處： International journal of machine tools & manufacture, 2013-09, Vol.72, p.50-57 版權： 2013 Elsevier Ltd 識別號： ISSN: 0890-6955 識別號： EISSN: 1879-2170 識別號： DOI: 10.1016/j.ijmachtools.2013.06.003

Wavelength-modulated heterodyne grating shearing interferometry for precise displacement measurement

title: Wavelength-modulated heterodyne grating shearing interferometry for precise displacement measurement abstract: 摘要： AbstractA wavelength-modulated heterodyne grating shearing interferometry using a birefringent crystal is proposed for two-dimensional displacement measurement. There is a difference in the optical path lengths of the p- and s- polarizations of the light beam in the birefringent crystal because of the double refraction caused by the birefringence. By passing through the unequal-path-length optical configuration, the wavelength-modulated light beam is converted into a heterodyne light beam having two frequencies. The modulated heterodyne light beam is further combined with grating-shearing interferometry based on the quasi-common-optical-path (QCOP) design concept. According to the working principle and the Jones calculation, the displacement information of a moving grating can be obtained by means of the optical phase variation resulting from the grating. Theoretical analysis shows that the measurement sensitivity of the proposed method is about 0.134°/nm. The experimental results indicate that the resolution is about 10 nm for the centimetric-level measurement range. 出版者： Berlin: Frontiers Media SA 出版日期： 2014-08-01 出處： Advanced Optical Technologies, 2014-08, Vol.3 (4), p.395-400 版權： Copyright Walter de Gruyter GmbH 2014 識別號： ISSN: 2192-8576 識別號： EISSN: 2192-8584 識別號： DOI: 10.1515/aot-2014-0027

Wavelength optimization using available laser diodes in spectral near-infrared optical tomography

title: Wavelength optimization using available laser diodes in spectral near-infrared optical tomography abstract: 摘要： For employing optimized wavelengths, a near-infrared (NIR) tomographic imaging system with multiwavelengths in a continuous wave (CW) enables us to provide accurate information of chromophores. In this paper, we discuss wavelength optimization with a selection from commercial laser diodes. Through theoretical analysis, the residual norm (R) and the condition number (κ) represent the uniqueness of a matrix problem and the smooth singular-value distribution of each chromophore, respectively. The optimum wavelengths take place for large R and small κ. We considered a total of 38 wavelengths of laser diodes in the range of 633-980 nm commercially available to discover optimum sets for a broad range of chromophore combinations. In the 38 wavelengths, there exists 501,942 (C538), 2,760,681 (C638), and 12,620,256 (C738) combinations of five, six, and seven wavelength sets, respectively, for accurately estimating chromophores (HbO , HbR, H O, and lipids), water, lipids, and the scattering prefactor A. With the numerical calculation, the top 10 wavelength sets were selected based on the principle of large R and small κ. In the study, the chromophore concentration for young and elderly women are investigated; finally, choosing the laser diodes with a wavelength of 650, 690, 705, 730, 870/880, 915, and 937 nm is recommended either for young or elderly women to construct a spectral NIR tomographic imaging system in the CW domain. Simulated data were used to validate the claims. 其他題名： Appl Opt 出版者： United States 出版日期： 2016-07-20 出處： Applied Optics, 2016-07, Vol.55 (21), p.5729-5737 資源來源： Optica Publishing Group Journals 識別號： ISSN: 1559-128X 識別號： EISSN: 2155-3165 識別號： EISSN: 1539-4522 識別號： DOI: 10.1364/AO.55.005729 識別號： PMID: 27463930

Water-based polyurethane 3D printed scaffolds with controlled release function for customized cartilage tissue engineering

title: Water-based polyurethane 3D printed scaffolds with controlled release function for customized cartilage tissue engineering abstract: 出版者： Elsevier BV 出版日期： 2016-03 出處： Biomaterials, 2016-03, Vol.83, p.156-168 識別號： ISSN: 0142-9612 識別號： DOI: 10.1016/j.biomaterials.2016.01.019