Microstructure and Mechanical Properties of (TiZrHf)50(NiCoCu)50 High Entropy Alloys

Chih‑Hsuan Chen,Yue‑Jin Chen,Jia‑Jyun Shen 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.5

The microstructure and mechanical properties of pseudo-binary (TiZrHf)50(NiCoCu)50 high entropy alloys(HEAs) with B2 matrix were investigated in this study. The studied HEAs includes Ti40Zr10Ni40Co5Cu5,Ti30Zr20Ni30Co10Cu10,Ti25Zr25Ni16.67Co16.67Cu16.67,Ti30Zr10Hf10Ni30Co10Cu10,Ti20Zr15Hf15Ni20Co15Cu15,andTi16.67Zr16.67Hf16.67Ni16.67Co16.67Cu16.67. XRD and SEM analyses revealed that all studied HEAs were a mixture of B2 andC15 intermetallic phases, instead of a single solid solution, due to their highly negative enthalpy of mixing and the relativelylarge difference in atomic radii. The B2 matrix was found capable of forming a solid solution of all six elements in a widecomposition range. The lattice constants of B2 and C15 phases increase linearly with increasing the difference in atomicradii. Additionally, the microhardness of these HEAs increases from 409 to 595 HV with the increasing difference in atomicradii as well. Compression tests demonstrated substitution of Zr with Hf can improve the ductility. In all studied HEAs, theTi30Zr10Hf10Ni30Co10Cu10HEA achieves a great balance between yield strength, ultimate compressive strength, and fracturestrain of 1574 MPa, 1933 MPa, and 6.5%, respectively.

Retraction Note: “Nonlinear Backstepping Control Design of LSM Drive System Using Adaptive Modified Recurrent Laguerre Orthogonal Polynomial Neural Network” [IJCAS (2017) 15(2):905-917]

Chih-Hong Lin 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.4

The Editor-in-Chief has retracted this article [1] because it contains significant overlap with a previous publication by the same author [2]. This article is therefore redundant. Author Chih-Hong Lin agrees to this retraction.

台灣對管制規範的改革 : 以對電子媒體核發臨時執照的運用為核心

吳志光 梨花女子大學校 法學硏究所 2015 法學論集 Vol.19 No.4

For the purposes of legal norms, all regulations are to overall efficiency, but excessive regulation will be mutual interference as to obstruct efficiency. The regulatory reform has become a responsibility of guarantor state. But for the fair competition or maintenance of social diversity shall be means special permission of regulation, this is the concerns of economic administrative law and Fair Trade Act. In particular, for regulation of electronic media involves freedom of expression and make it easier for controversial issue. In July 2005 Taiwan’s Government unprecedentedly rejected seven satellite broadcasting and television operator's application for the renewal of the operation license. At the time it caused much controversy. In support of the rule of law and procedures, which has a certain worth exploring. How to avoid producing all or none as a result of regulation, traditionally mainly to make administrative disposition with the incidental provision of agrees to the application licensing, mostly is the "conditions" or "burden" manner. But this way is not without controversy, in particular administrative discretion often become the focus of controversy. In 2007 the Cable Radio and Television Act amendments to new articles 35-1,1) it is creation of the "temporary operation license” as a new models of regulation. The regulatory reform is also as a responses of controversy in 2005. The temporary operation license could replace direct refused to apply for the renewal of the operation license, and also can be replaced by making a provisional injunction of Administrative Court. More importantly, the temporary operation license created the regulatory measures for the time foresee the possibility, this is the lack of the administrative disposition with incidental provision by the advantages. After all the purpose of regulation to public interests. At the same time how to balance the rights of the applicant of operation license, the temporary operation license should be the greatest common divisor.

Study of Feature-Based Image Capturing and Recognition Algorithm

Chih-Hong Kao,Sheng-Ping Hsieh,Chih-Cheng Peng 제어로봇시스템학회 2010 제어로봇시스템학회 국제학술대회 논문집 Vol.2010 No.10

In the field of applied computer vision, the three-dimensional (3D) object recognition is a very important technique which can be used to determine objects from a certain direction of the image for arbitrary 3D objects. These skills are useful in military applications, such as moving target recognition and coastal surveillance. Computer vision recognition allows fast response and all day long reconnaissance. The purpose of establishing a ship recognition system is to research and develop effective ship contour capture in the natural sea environment. We can develop a ship recognition system that is reliable and fast based on a database of ship images. We propose a recognition algorithm for ship images. This system utilizes gradient vector flow to capture the ship image contour first and calculates the geometric eigenvalue using this contour and Fourier descriptor. The eigenvalues are used to perform separate rough and detailed recognition. A graphic user interface is developed and the validity of the proposed technique is demonstrated using identifying images.

Precipitation Behavior of σ Phase in Fusion Zone of Dissimilar Stainless Steel Welds during Multi-Pass GTAW Process

( Chih Chun Hsieh ),( Tao Chih Chang ),( Dong Yih Lin ),( Ming Che Chen ),( Wei Te Wu ) 대한금속재료학회 ( 구 대한금속학회 ) 2007 METALS AND MATERIALS International Vol.13 No.5

The purpose of this study is to investigate the precipitation characteristics of σ phase in the fusion zone of stainless steel welds at various welding passes during a tungsten arc welding (GTAW) process. The morphology, quantity, and chemical composition of the δ-ferrite and σ phase were analyzed using optical microscopy (OM), a ferritscope (FS), a X-ray diffractometer (XRD), scanning electron microscopy (SEM), an electron probe micro-analyzer (EPMA), and a wavelength dispersive spectrometer (WDS), respectively. Massive δ-ferrite was observed in the fusion zone of the first pass welds during welding of dissimilar stainless steels. The σ phase precipitated at the inner δ-ferrite particles and decreased δ-ferrite content during the third pass welding. The σ and δ phases can be stabilized by Si element, which promoted the phase transformation of δ→σ + γ2 in the fusion zone of the third pass welds. It was found that the σ phase was a Fe-Cr-Si intermetallic compound found in the fusion zone of the third pass welds during multi-pass welding.

Effect of a Carbon Additive on the TbCu7-type Melt-spun Sm(Co, M)7 (M=Ti, Zr, Hf, V and Ge) Ribbons

Chih-Chieh Hsieh,Shih-Teng Huang,Jin-Sheng Guo,Chih-Wei Shih,Wen-Cheng Chang,Huang-Wei Chang,Chun-Chung Shaw 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.63 No.3

The effect of a carbon additive on the microstructure and the magnetic properties of melt-spunSmCo7−xMxCy (M=Ti, Zr, Hf, V and Ge; x = 0 - 0.3 and y = 0 - 0.1) ribbons was studied. Based on the XRD and the TEM analyses, a pure 1:7 phase could be formed for the C-containingribbons with M= Ti and Ge. However, carbide phases, i.e., Sm2C3 for M=Zr and Hf, and SmCoC2for M=V, respectively, were found. Nevertheless, a slight C addition may effectively refine themicrostructure and improve both the intrinsic coercvity and the magnetic energy product in all thestudied ribbons. Among them, the SmCo6.9V0.1C0.1 ribbons with r = 58.7 emu/g, iHc = 13.5kOe and (BH)max = 9.3 MGOe, and the SmCo6.9Hf0.1C0.1 ribbons with r = 61.6 emu/g, iHc =11.8 kOe and (BH)max = 10.3 MGOe are most suitable for the bonded magnet applications.

Static analysis of multiple graphene sheet systems in cylindrical bending and resting on an elastic medium

Chih-Ping Wu,Chih-Chen Lin 국제구조공학회 2020 Structural Engineering and Mechanics, An Int'l Jou Vol.75 No.1

An asymptotic local plane strain elasticity theory is reformulated for the static analysis of a simply-supported, multiple graphene sheet system (MGSS) in cylindrical bending and resting on an elastic medium. The dimension of the MGSS in the y direction is considered to be much greater than those in the x and z directions, such that all the field variables are considered to be independent of the y coordinate. Eringen’s nonlocal constitutive relations are used to account for the small length scale effects in the formulation examining the static behavior of the MGSS. The interaction between the MGSS and its surrounding foundation is modelled as a Winkler foundation with the parameter kw, and the interaction between adjacent graphene sheets (GSs) is considered using another Winkler model with the parameter cw. A parametric study with regard to some effects on the static behavior of the MGSS resting on an elastic medium is undertaken, such as the aspect ratio, the number of the GSs, the stiffness of the medium between the adjacent layers and that of the surrounding medium of the MGSS, and the nonlocal parameter.

Effects of Additives of CaO and Rare-Earth Oxides on the Sintering Behavior of AlN Ceramics

Chih-Hung Chu,Yun-Hwei Shen,Chih-Peng Lin,Shaw-Bing Wen 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.5

The effect of additives of CaO plus three different rare-earth oxides (Y, Sm and Gd, separately) on the sintering behavior of AlN ceramics has been evaluated at 1700℃ by using a MoSi2 heater and ambient atmosphere. The results of density measurements show that the atomic weight of the rare-earth element may substantially affect the apparent density of the sintered AlN specimen due to the kinetics of atomic diffusion during sintering. The optimum results of this study show that these additives are effective in obtaining an apparent density of 3.26 g/cm3 (approaching a 100 % theoretical density of AlN). The Vicker's hardness of the sintered AlN can reach a high value of 1310 kg/mm2 and an apparent density of 3.34 g/cm3. A longer soaking time of between 3 and 5 h is necessary to practically eliminate the minor oxide phases. The effect of additives of CaO plus three different rare-earth oxides (Y, Sm and Gd, separately) on the sintering behavior of AlN ceramics has been evaluated at 1700℃ by using a MoSi2 heater and ambient atmosphere. The results of density measurements show that the atomic weight of the rare-earth element may substantially affect the apparent density of the sintered AlN specimen due to the kinetics of atomic diffusion during sintering. The optimum results of this study show that these additives are effective in obtaining an apparent density of 3.26 g/cm3 (approaching a 100 % theoretical density of AlN). The Vicker's hardness of the sintered AlN can reach a high value of 1310 kg/mm2 and an apparent density of 3.34 g/cm3. A longer soaking time of between 3 and 5 h is necessary to practically eliminate the minor oxide phases.

Clinical Features and Computed Tomography Characteristics of Non-Klebsiella pneumoniae Liver Abscesses in Elderly (>65 Years) and Nonelderly Patients

Chih-Weim Hsiang,Wei-Chou Chang,Chang-Hsien Liu,Hsiu-Lung Fan,Kai-Hsiung Ko,Chih-Yung Yu,Hong-Hau Wang,Wen-I Liao,Hsian-He Hsu 연세대학교의과대학 2015 Yonsei medical journal Vol.56 No.2

Purpose: To compare the clinical and computed tomography (CT) appearances of liver abscesses caused by non-Klebsiella pneumoniae bacterial pathogens in elderly and nonelderly patients. Materials and Methods: Eighty patients with confirmed non-Klebsiella pneumoniae liver abscesses (non-KPLAs) were enrolled and dividedinto two age groups: elderly (age ≥65 years, n=42) and nonelderly (age <65 years, n=38). Diagnosis of non-KPLA was established by pus and/or blood culture. We compared clinical presentations, outcomes, and CT characteristics of the two groups, and performed multivariate analysis for significant variables and receiver-operating-characteristic analysis to determine the cutoff value of abscess diameter for predicting non-KPLA. Results: Elderly patients with non-KPLA were associatedwith a longer hospital stay (p<0.01). Regarding etiology, biliary sources had a strong association in the elderly group (p<0.01), and chronic liver diseases were relatedto the nonelderly group (p<0.01). Non-KPLAs (52.5%) tended to show a large, multiloculated appearance in the elderly group and were associated with bile duct dilatation (p<0.01), compared with the nonelderly group. The abscess diameter (cutoff value, 5.2 cm; area under the curve, 0.78) between the two groups was predicted. In multivariate analysis, underlying biliary tract disease [odds ratio (OR), 3.58, p<0.05], abscess diameter (OR, 2.40, p<0.05), and multiloculated abscess (OR, 1.19, p<0.01) independently predicted elderly patients with non-KPLA. Conclusion:In the elderly patients with non-KPLA, a large, multiloculated abscess with a diameter greater than 5.2 cm was the predominant imaging feature.

Effect of Landslide Deposition on Soil Properties in the Xitou Experiment Forest, Central Taiwan

Chih-Hsin Cheng,Sheng-Che Hsiao,Yu-Hsuan Huang,Chih-Yu Hung,Chuang-Wen Pai,Chiu Ping Chen,Oleg Menyailo 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6