Irreducible Elbow Dislocation Associated with Hill-Sachs-like Lesion over the Capitellum

Hung-Kai Weng,Wei-Lun Chang,Ming-Long Yeh,Wei-Ren Su,Kai-Lan Hsu 대한견주관절의학회 2019 대한견주관절의학회지 Vol.22 No.1

An improved regularized particle fi lter for remaining useful life prediction in nuclear plant electric gate valves

Ren-yi Xu,Hang Wang,Min-jun Peng,Yong-kuo Liu 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.6

Accurate remaining useful life (RUL) prediction for critical components of nuclear power equipment is animportant way to realize aging management of nuclear power equipment. The electric gate valve is oneof the most safety-critical and widely distributed mechanical equipment in nuclear power installations. However, the electric gate valve's extended service in nuclear installations causes aging and degradationinduced by crack propagation and leakages. Hence, it is necessary to develop a robust RUL predictionmethod to evaluate its operating state. Although the particle filter(PF) algorithm and its variants can dealwith this nonlinear problem effectively, they suffer from severe particle degeneracy and depletion, whichleads to its sub-optimal performance. In this study, we combined the whale algorithm with regularizedparticle filtering(RPF) to rationalize the particle distribution before resampling, so as to solve theproblem of particle degradation, and for valve RUL prediction. The valve's crack propagation is studiedusing the RPF approach, which takes the Paris Law as a condition function. The crack growth is observedand updated using the root-mean-square (RMS) signal collected from the acoustic emission sensor. Atthe same time, the proposed method is compared with other optimization algorithms, such as particleswarm optimization algorithm, and verified by the realistic valve aging experimental data. The conclusion shows that the proposed method can effectively predict and analyze the typical valve degradationpatterns

A Heuristic Algorithm for the Reliability Optimization of a Distributed Communication Network

Hung, Chih-Young,Yang, Jia-Ren,Park, Dong-Ho,Liu, Yi-Hsin The Korean Reliability Society 2008 International Journal of Reliability and Applicati Vol.9 No.1

A heuristic algorithm for reliability optimization of a distributed network system is developed so that the reliability of a large system can be determined efficiently. This heuristic bases on the determination of maximal reliability set of maximum node capacity, maximal link reliability and maximal node degree.

Crushing study for interlocked armor layers of unbonded flexible risers with a modified equivalent stiffness method

Ren, Shaofei,Liu, Wencheng,Song, Ying,Geng, Hang,Wu, Fangguang The Society of Naval Architects of Korea 2019 International Journal of Naval Architecture and Oc Vol.11 No.1

Interlocked armor layers of unbonded flexible risers may crush when risers are being launched. In order to predict the behavior of interlocked armor layers, they are usually simplified as rings with geometric and contact nonlinearity ignored in the open-literature. However, the equivalent thickness of the interlocked armor layer has not been addressed yet. In the present paper, a geometric coefficient ${\gamma}$ is introduced to the equivalent stiffness method, and a linear relationship between ${\gamma}$ and geometric parameters of interlocked armor layers is validated by analytical and finite element models. Radial stiffness and equivalent thickness of interlocked armor layers are compared with experiments and different equivalent methods, which show that the present method has a higher accuracy. Furthermore, hoop stress distribution of interlocked armor layer under crushing is predicted, which indicates the interlocked armor layer can be divided into two compression and two expansion zones by four symmetrically distributed singular points.

A Vertically Intersected Dual Axes Modularized Actuator System (DAMA)

Ren-Jeng Wang,Han-Pang Hung,Tz-How Huang,His-Fan Liao 제어로봇시스템학회 2010 제어로봇시스템학회 국제학술대회 논문집 Vol.2010 No.10

A Vertically Intersected Dual Axes Modularized Actuator System (DAMA) designed for humanoid robots is developed in this paper. The DAMA consists of two independent joint systems, joint 01 and joint02. Joint 01 uses a harmonic drive while joint02 uses a cable arrangement. Based on the simulations of ADMAS and MATLAB software packages, the system dynamic properties can be observed. The system structure is further refined using finite element analysis. In addition, the hardware and software control systems of DAMA are developed. The architecture of hardware is composed of notebook computer, a USB to RS-232 module, an RS-232 to CAN Bus Module and two independent-joint controller modules. The software control system (user interface) is written by Visual C++ 2005 to enable users to manipulate a two-axial robot easily. The system employs a simple, but effective, PID scheme to independently control the DAMA’s two joints. The experimental result shows that, for an S curve input position command, the DAMA’s two independent joints rotate and track the command well. Hence, DAMA can be used as a generic module for a multiple degree-of-freedom system.

Apoptotic effects of 1,5-bis-(5-nitro-2-furanyl)-1,4-pentadien-3- one on Drosophila SL2 cells

Yuan-Hang Ren,Hong Jin,Ke Tao,Tai-Ping Hou 대한독성 유전단백체 학회 2015 Molecular & cellular toxicology Vol.11 No.2

n recent years, concerns over the potential impact of synthetic pesticides on the environment have promoted the research and development of environmentally friendly “green” pesticides. In the current study, we utilized a green biomimetic insecticide, 1,5-bis- (5-nitro-2-furanyl)-1,4-pentadien-3-one (compound C), to examine its cytotoxicity on an insect cell line, Drosophila melanogaster (SL2). Results from MTT assay showed cells treated with 100 μM of compound C for 48 h significantly inhibited the growth of SL2 cells by 87.71±0.96%. We subsequently attempted to illustrate the act on mechanism of compound C at the cellular level and found that it initiated apoptosis through a mitochondrial-dependent mechanism that increased the activity of caspase-3 and altered the cell cycle. These results suggest that the green biomimetic insecticide, compound C, is a novel and potent inducer of insect cell apoptosis.

Influence of an Advanced Buffer Layer on the Optical Properties of an InGaN/GaN MQW Grown on a (111) Silicon Substrate

Da-Ren Hang,M. Heuken,M.C. Chou,M.H. Hsieh 한국물리학회 2007 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.50 No.3

We study the influence of a buffer layer on the optical properties of InGaN/GaN multiple quantum wells (MQWs) grown on silicon substrates by using metalorganic vapor phase epitaxy. To overcome the large lattice mismatch and the difference in the thermal expansion coefficients by which a high dislocation density occurs, we grow the MQWs on an advanced buffer structure consisting of low-temperature (LT) AlN and a high-temperature (HT) AlN/AlGaN/GaN stack. The Raman spectra confirm that the biaxial tensile strain is reduced by the insertion of the alternating LT and HT buffer layers. Moreover, we find the room-temperature internal quantum efficiency can be improved. Our results suggest that the enhanced optical performance comes from the reduced number of nonradiative recombination centers brought about by the LT and HT composite buffer layers.

Structural Design and Property Evaluations of Foam-based Composite Materials: Effect of Perforation Depth and Foam Density on the Mechanical, Sound Absorption, and Thermal Properties

Ruei-Ren Ou,Chen-Hung Huang,Ching-Wen Lou,Jia-Horng Lin 한국섬유공학회 2021 Fibers and polymers Vol.22 No.3

Nonwoven fabrics and rigid polyurethane foam(PUF) are commonly used materials as building materials, butthere are few studies on combining both materials and reporting characteristic evaluations for the application. In this study, N/L/Fr nonwoven fabrics are combined with PUF to produce N/PUF composites, and then a needle punching machine is usedfor perforation, thereby produces perforated N/PUF composites. With PUF densities being 70 kg/m3 and 80 kg/m3, aperforation depth of 100 % results in significantly decreasing mechanical properties. Based on the results of thermalconductivity coefficient, the employment of needle punch process results in a decrease in the thermal insulation of N/PUFcomposite; however, the descending level is comparatively smaller when PUF is made of a greater density. In thethermogravimetric analysis (TGA), the char residue is 4.86 % for PUF and 11.68 % for N/PUF composites, indicating thatN/L/Fr nonwoven fabrics improve the thermal stability of PUF. As per limiting oxygen index (LOI), the part of proposed N/PUF composites that first contacts the flame is N/L/Fr nonwoven fabrics, which causes an LOI of 33 when in practicalapplication and resembles the LOI (33) of N/L/Fr nonwoven fabrics. Based on the test results, the optimal perforated N/PUFcomposites are made of a PUF density of 80 kg/m3 and a perforation depth of 75 %, and the optimal compression strength is375.29 kPa, which increases by 10.96 %. In addition, the proposed products have the same impact absorption capacity (5.88 J) asthat of N/PUF composites, which absorb a total of 98.16 % impact energy. The sound absorption is improved in the frequencyband of 800-2500 Hz, which broadens the sound absorption bandwidth and benefits the application as being sound absorbentmaterials.

Crushing study for interlocked armor layers of unbonded flexible risers with a modified equivalent stiffness method

Shaofei Ren,Wencheng Liu,Ying Song,Hang Geng,Fangguang Wu 대한조선학회 2019 International Journal of Naval Architecture and Oc Vol.11 No.1

Interlocked armor layers of unbonded flexible risers may crush when risers are being launched. In order to predict the behavior of interlocked armor layers, they are usually simplified as rings with geometric and contact nonlinearity ignored in the open-literature. However, the equivalent thickness of the interlocked armor layer has not been addressed yet. In the present paper, a geometric coefficient g is introduced to the equivalent stiffness method, and a linear relationship between g and geometric parameters of interlocked armor layers is validated by analytical and finite element models. Radial stiffness and equivalent thickness of interlocked armor layers are compared with experiments and different equivalent methods, which show that the present method has a higher accuracy. Furthermore, hoop stress distribution of interlocked armor layer under crushing is predicted, which indicates the interlocked armor layer can be divided into two compression and two expansion zones by four symmetrically distributed singular points.

A national survey on how to improve traditional Chinese medicine learning internationally: Perceptions from both teachers and students

Zhu Yu-Hang,Yan Wu,Hao Zhang,Yanfei Zhao,Yule Ren,Wei Hu,Pan Li,Huiyi Wang,Ying Wang,Boda Zhang,Yujie Wang,Hongwen Yuan,Jiping Zhang,Wenqiang Li,Yufang Zhao,Jie Zhao,Yedong Shi,Yanye Shu,Xiao Zhang,Ya 한국한의학연구원 2022 Integrative Medicine Research Vol.11 No.4

Background With the increasing popularity of traditional Chinese medicine (TCM) by the global community, how to teach basic knowledge of TCM to international students and improve the teaching quality are important issues for teachers of TCM. The present study was to analyze the perceptions from both students and teachers on how to improve TCM learning internationally. Methods A cross-sectional national survey was conducted at 23 universities/colleges across China. A structured, self-reported on-line questionnaire was administered to 34 Chinese teachers who taught TCM course in English and to 1016 international undergraduates who were enrolled in the TCM course in China between 2017 and 2021. Results Thirty-three (97.1%) teachers and 900 (88.6%) undergraduates agreed Chinese culture should be fully integrated into TCM courses. All teachers and 944 (92.9%) undergraduates thought that TCM had important significance in the clinical practice. All teachers and 995 (97.9%) undergraduates agreed that modern research of TCM is valuable. Thirty-three (97.1%) teachers and 959 (94.4%) undergraduates thought comparing traditional medicine in different countries with TCM can help the students better understand TCM. Thirty-two (94.1%) teachers and 962 (94.7%) undergraduates agreed on the use of practical teaching method with case reports. From the perceptions of the undergraduates, the top three beneficial learning styles were practice (34.3%), teacher's lectures (32.5%), case studies (10.4%). The first choice of learning mode was attending to face-to-face teaching (82.3%). The top three interesting contents were acupuncture (75.5%), Chinese herbal medicine (63.8%), and massage (55.0%). Conclusion To improve TCM learning among international undergraduates majoring in conventional medicine, integration of Chinese culture into TCM course, comparison of traditional medicine in different countries with TCM, application of the teaching method with case reports, and emphasization of clinical practice as well as modern research on TCM should be fully considered.