Tungfang Design Institute

Kaohsiung, Taiwan

Tungfang Design Institute

Kaohsiung, Taiwan
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Hu S.-Y.,Tungfang Design Institute | Lee Y.-C.,Tungnan University | Chen B.-J.,National Taiwan Ocean University
Journal of Alloys and Compounds | Year: 2017

In this work, CuInS2 (CIS) nanocrystals are successfully synthesized by microwave-assisted technique and further calcined at several different temperatures with or without additional Ar ambient. The XRD measurements showed that a significant recrystallization might have occurred with the help of Ar ambient to introduce the increasing relative intensity of the (112) diffraction peak. Furthermore, the eliminated organic-related structures and the enlarging CuInS2 nanocrystals are evidently confirmed by FTIR and SEM, respectively. Raman analysis of the CIS(CH) mode of the CuInS2 nanocrystals in the calcined temperature range of 200–400 °C is presented while the lineshape is described and calculated by the spatial correlation model corresponding to the presence of a long-range order in the higher calcined temperature of CuInS2 nanocrystals. Transmission can be used to figure out that the calcined CuInS2 nanocrystals with Ar are related with the modification of the optical band gap energy. © 2016 Elsevier B.V.

Cheng F.J.,Tungnan University | Hu S.Y.,Tungfang Design Institute | Chen L.Y.,National Taiwan University of Science and Technology | Lee Y.C.,Tungnan University | And 3 more authors.
IOP Conference Series: Materials Science and Engineering | Year: 2017

Recently, organometal halide perovskites are widely considered as promising materials in light emitting and lasing devices due to their potential optical properties. The luminescence characteristics of CH3NH3PbI3-xClx perovskite material have investigated by temperature-dependent PL measurements. We suggest that the tetragonal inclusions in the orthorhombic phase of CH3NH3PbI3-xClx thin film at low temperature result in the 12 K PL spectrum with a broad emission band. In addition, the PL peak of CH3NH3PbI3-xClx thin film as a function temperature shows a tendency of buleshift, which is contrary to the typical tendency of redshift for traditional semiconductor materials. © Published under licence by IOP Publishing Ltd.

Hu S.-Y.,Tungfang Design Institute | Chou W.-C.,National Chiao Tung University | Weng Y.-H.,National Taiwan Ocean University
Journal of Alloys and Compounds | Year: 2015

Ternary alloys of ZnMgO samples with different magnesium contents have been grown by molecular beam epitaxy on the sapphire substrates. Room temperature photoluminescence energy of ZnMgO shifted as high as 3.677 eV by increasing Mg contents corresponding to the higher Urbach average localization energy which indicates more randomness in the alloys with higher Mg contents. XRD results are also verified that the c-axis length decreases as the increasing Mg contents linking to the increased tensile stress produced by the Mg atoms. Raman spectra analyzed by the spatial correlation model to describe that the linewidth Γ is decreased but the correlation length L is increased as the increasing of Mg contents. © 2015 Elsevier B.V.

Wu T.Y.,National Taiwan Ocean University | Huang Y.S.,National Taiwan Ocean University | Hu S.Y.,Tungfang Design Institute | Lee Y.C.,Tungnan University | And 4 more authors.
Solid State Communications | Year: 2016

We have investigated the luminescence characteristics of Zn1-xCdxO thin films with different Cd contents grown by molecular beam epitaxy system. The temperature-dependent photoluminescence (PL) and excitation power-dependent PL spectra were measured to clarify the luminescence mechanisms of the Zn1-xCdxO thin films. The peak energy of the Zn1-xCdxO thin films with increasing the Cd concentration is observed as redshift and can be fitted by the quadratic function of alloy content. The broadened full-width at half-maximum (FWHM) estimated from the 15 K PL spectra as a function of Cd content shows a larger deviation between the experimental values and theoretical curve, which indicates that experimental FWHM values are affected not only by alloy compositional disorder but also by localized excitons occupying states in the tail of the density of states. The Urbach energy determined from an analysis of the lineshape of the low-energy side of the PL spectrum and the degree of localization effect estimated from the temperature-induced S-shaped PL peak position described an increasing mean exciton-localization effects in ZnCdO films with increasing the Cd content. In addition, the PL intensity and peak position as a function of excitation power are carried out to clarify the types of radiative recombination and the effects of localized exciton in the ZnCdO films with different Cd contents. © 2016 Elsevier Ltd. All rights reserved.

Cheng F.J.,Tungnan University | Lee Y.C.,Tungnan University | Hu S.Y.,Tungfang Design Institute | Lin Y.C.,National Taiwan Ocean University | And 2 more authors.
IOP Conference Series: Materials Science and Engineering | Year: 2016

In this work, the carrier dynamics in Zn1-xCdxO thin films with different Cd contents grown by molecular beam epitaxy system have been investigated using photoluminescence and time-resolved photoluminescence measurements. The carrier lifetime can be estimated from the PL decay curve fitted by triple exponential function. The emission energy dependence and temperature dependence of the PL decay time indicate that carrier localization dominate the luminescence mechanism of the ZnCdO alloy semiconductor. © Published under licence by IOP Publishing Ltd.

Hu S.Y.,Tungfang Design Institute | Lee Y.C.,Tungnan University | Weng Y.H.,National Taiwan Ocean University | Ferguson I.T.,University of North Carolina at Charlotte | Feng Z.C.,National Taiwan University
Journal of Alloys and Compounds | Year: 2014

Samples containing thin InAlGaN layers grown on c-Al2O 3 substrates by metalorganic chemical vapor deposition have been studied experimentally and theoretically with the help of photoluminescence measurements between 10 and 300 K. From the analysis of the temperature dependence photoluminescence spectra with the modified Bose-Einstein equation, the localization energy of excitons was estimated successfully and the value is found out to be well correlated to the strength of the electron/exciton-phonon interaction as well as the stress observed in the X-ray diffraction spectra. These results are also confirmed that the c-axis length decreases as the increasing Al/In ratio corresponding to the decreased compressive stress which would be attributed to the increased tensile stress formed by Al atoms incorporated. © 2013 Elsevier B.V. All rights reserved.

Yang Y.-F.,National University of Tainan | Yang Y.-F.,Chung Hwa University of Medical Technology | Chao C.-J.,National University of Tainan | Chao C.-J.,TungFang Design Institute | Chang C.-K.,National University of Tainan
Proceedings of the 21st International Conference on Computers in Education, ICCE 2013 | Year: 2013

This paper provides a content analysis of studies in Mobile Assisted Language Learning (MALL) that were published in ten Social Science Citation Index (SSCI) journals, including ReCALL, Computers & Education, and Computer Assisted Language Learning so on. Only papers that were identify as MALL-related, full-length paper, and published during 2008 to 2012 were analyzed. After comprehensive review, 44 articles were used for this study to answer the following questions: (1) what is the status of those MALL articles published in these selected journals from 2008 to 2012, (2) what research sample groups related to MALL were selected in these articles from 2008 to 2012, and (3) what language learning topics related to MALL were adopted in these articles from 2008 to 2012? According the analysis results, the distribution of articles is 12, 6, 7, 10, and 9 from 2008 to 2012. It was found that research samples in higher education were selected most (31). We can find that the elementary school students (3), high school students (5), and teachers (1) are seldom used in MALL activities. Hence, we may claim one of the trends shaping the MALL studies from 2008 to 2012 is to exploit college student as convenience sample. On the other hand, the results implied that MALL researchers should pay more attention on applying MALL to elementary, high school, and others because it becomes popular for K-12 students using mobile devices to access digital information. Overall, the analysis results provide insights and patterns of MALL research trends for language instructors and researchers. Consequently, this study contributes to clarify the route of pass five years and indicate a feasible roadmap for MALL research.

Chen N.,Tungfang Design Institute | Tzeng C.-T.,National Cheng Kung University | Tsay Y.,National Cheng Kung University | Chen C.,National Cheng Kung University
Indoor Air 2014 - 13th International Conference on Indoor Air Quality and Climate | Year: 2014

Aiming at the hot and humid climatic conditions in southern Taiwan, this study discusses the terminologies of buildings, namely the impact of balcony on natural ventilation and indoor temperature, and probes into two vertical air guide designs (general and ventilated) of balcony, as well as reviews the impact of balcony depth. The research methods include field measurement and numerical simulation. The findings show that the air guide balcony of this study can be adopted for small depth, and the balcony with vertical air deflector design is recommended for large depth, not only increasing indoor air velocity, but also improving the warming phenomenon resulted from the increase of balcony depth.

Shih Y.,National Cheng Kung University | Liu K.,Tungfang Design Institute | Chiang C.,National Cheng Kung University | Chen N.,Tungfang Design Institute
Energy and Buildings | Year: 2014

This research is to assist the ministry of education in promoting the transformation of idle spaces in Taiwanese schools into "Energy-resource education centres". This project uses expert consultant teams to assist the school in redesigning of its idle spaces to incorporate the goals of sustainable energy-resource education. Through renovation of construction of displayable educational equipment, the project aims to enliven these spaces into educational display areas. This fits with special energy-resource classes and creative educational activities to build a low carbon school ground and advance the cause of sustainable development. © 2013 Elsevier B.V. All rights reserved.

Chen C.-I.,I - Shou University | Huang S.-J.,TungFang Design Institute
Proceedings of 2013 4th International Asia Conference on Industrial Engineering and Management Innovation, IEMI 2013 | Year: 2014

Grey theory is popular formany years. GM(1,1) is the most used model in grey theory. In the model, there are two coefficients a and b which are determined by lease square method. Base on our research result, the grey development coefficient a should not be zero. If it is, the prediction result is totally erroneous. The correct way to solve this problem is to adopt L'Hôpital Rule. In this paper, we also demonstrate how nonlinear grey Bernoulli model could avoid the appearance the singular situation and increase the prediction precision. © 2014 Springer-Verlag Berlin Heidelberg..

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