Trajectory Planning of Robot Manipulators in Cartesian Space

Xu, Xiang-Rong,Choi, Young-Hyu,Chung, Won-Jee,Ma, Xiang-Feng 國立 昌原大學校 産業技術硏究所 1998 産技硏論文集 Vol.12 No.-

이 논문은 Luh의 연구[5]에 기초한 로봇의 CP(Continuous Path) 운동 궤적계획에 대한 알고리즘을 제시한다. 이동 경로는 직각좌표계의 매개변수 방정식 그룹으로 표현된다. 시간간격(0,T)은 m등분으로 분할되고 각 분할부분의 다항식 계수는 순환 형식으로 얻어진다. 본 논문에서는 최소시간 궤적계획 및 m분할 결정에 대한 연구를 하였다. 3차 곡선 스플라인 함수(cubic spline function) 방법과 비교해 보면, 제안된 알고리즘이 컴퓨터 프로그램으로 쉽게 변활될 뿐만 아니라 연산량이 적다.

Novel AgCl/Ag2SO3 Hybrids as a Visible-Light-driven Photocatalyst: Preparation, Characterization, and Degradation of Rhodamine-B and Methyl Orange

Xiang-Feng Wu,Yi-Jin Wang,Zuo-Lin Cao,Yan-Mei Feng,Hui Li,Chen-Xu Zhang,Jun-Zhang Su,Jia-Rui Zhang,Yi-Wei Wang,Kai-Yuan Wang,Guo-Wen Sun 대한화학회 2018 Bulletin of the Korean Chemical Society Vol.39 No.7

The novel AgCl/Ag2SO3 hybrids as an efficient photocatalyst had been fabricated by an in situ synthetic method. The correlations between the structure and the photocatalytic properties of the as-fabricated hybrids were analyzed. Experimental results exhibited that with increasing the amount of Ag2SO3, the degradation rate of the as-obtained samples was firstly increased and then decreased under the visible light irradiation. When the mass ratio of AgCl to Ag2SO3 was 1:2, in 30?min, it displayed the highest degradation rate of 99.2% for rhodamine-B, which was obviously higher than 46.1, 60.5, and 14.6% of pure AgCl, Ag2SO3, and TiO2 (P25), respectively. Similar results could be found in degradation of methyl orange. It had the maximum of 97.4% in 90?min, which was higher than 55.2, 48.7, and 12.7% of pure AgCl, Ag2SO3, and P25, respectively. Moreover, the as-prepared hybrids possessed the enhanced separation and transfer of photo-generated electron?hole pairs compared to the pure samples. In addition, the holes and superoxide radicals played the dominant role and the hydroxyl radicals played the secondary role during the process of photocatalytic degradation.

A Method for the Analysis of Robot Dynamics

Xu, Xiang-Rong,Choi, Young-Hyu,Chung, Won-Jee,Ma, Xiang-Feng 國立 昌原大學校 産業技術硏究所 1998 産技硏論文集 Vol.12 No.-

이 논문은 Kane의 동역학 방정식에 기초한 로봇 동역학의 새로운 循環 알고리즘을 제시한다. 이 알고리즘은 Kane의 동역학 방정식과 뉴톤-오일러 공식을 이용하여 얻어진다. 라그랑지-오일러(L-E)와 뉴우톤-오일러(N-E) 등과 같은 전통적 알고리즘과는 달리, 제안된 알고리즘은 간단하면서 確然하고, 閉체인을 그대로 포함된 로봇의 동역학을 푸는데 사용되어진다. 또한 이 알고리즘은 循環형태로 표현되어서 컴퓨터상에 구현하기 쉽기 때문에 로봇의 CAD(Computer0Aided Design)에 적합하다.

NUMERICAL ANALYSIS AND THEORETICAL PREDICTION OF AXIAL CRUSHING CHARACTERISTICS OF MIXED THIN-WALLED TUBES WITH DUAL-VARIABLE ATTRIBUTE

Xu Feng Xiang,Niu Xiao Qiang,Shao Tian Ru 한국자동차공학회 2022 International journal of automotive technology Vol.23 No.6

Thin-walled structures with varying thickness (single variable attribute) had been proven to be able improve energy absorption characteristics. In order to further study the energy absorption characteristics of thin-walled structures whose material properties changed as the thickness changing, a novel type of mixed thin-walled tube with axially-varying thickness and material were proposed in this paper. The finite element (FE) model was validated under axial quasi-static loading firstly, and seven groups simulation models of thin-walled tubular structure were established. The simulation results showed that the dual-variable attribute tubes can ensure high energy absorption and reduce the initial peak crushing force effectively in the crushing process. Furthermore, the maximum crushing force efficiency of steel-aluminum mixed tube can reach 2.77, while the aluminum mixed tube increased the crushing force efficiency to 1.24. Subsequently, a analytical model for dual-variable attribute tube was established and the theoretical mean crushing force calculation formula can be derived. The simulation and theoretical results were wirelessly close, except that the error of SUT5 was about 11 %. Therefore, the theoretical prediction results were in good agreement with the simulation results, and the theoretical prediction method can provide some reference for the design of double variable tube.

A New Approach for Modeling and Computation of Dynamics of Robots Containing Closed Chains

Xu,Xiang-Rong,Ma,Xiang-Feng,Choi,Young-Hyu,Chung,Won-Jee 창원대학교 공작기계기술연구센터 1999 연구업적집 Vol.1 No.1

This paper presents a new recursive algorithm of robot dynamics based on the Kane's dynamic equations and Newton-Euler formulations. Differing from Kane's work, the algorithm is general-propose and can be easily realized on computers. It is suited not only for robots with all rotary joints but also for robots with some prismatic joints Formulations of the algorithm keep the recurrence characteristics of the Newton-Euler formulations, but possess stronger physical significance. Unlike the conventional algorithms, such as the Lagrange and Newton-Euler algorithm, etc, the algorithm can be used to deal with dynamics of robots containing closed chains without cutting the closed chains open. In addition, this paper makes a comparison between the algorithm and those conventional algorithms from the number of multiplications and additions.

MLH1 Polymorphisms and Cancer risk: a Meta-analysis Based on 33 Case-control Studies

Xu, Jia-Li,Yin, Zhi-Qiang,Huang, Ming-De,Wang, Xie-Feng,Gao, Wen,Liu, Ling-Xiang,Wang, Rong-Sheng,Huang, Pu-Wen,Yin, Yong-Mei,Liu, Ping,Shu, Yong-Qian Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.3

Objective: Cumulative evidence suggests that MLH1, the key component in the mismatch pathway, plays an important role in human cancers. Two potential functional polymorphisms (-93G>A and I219V) of MLH1 have been implicated in cancer risk. The aim of this meta-analysis was to summarize the evidence for associations. Methods: Eligible studies were identified by searching the electronic literature PubMed, ScienceDirect and Embase databases for relevant reports and bibliographies. Studies were included if of case-control design investigating MLH1 polymorphisms (-93G>A and I219V) and cancer risk with sufficient raw data for analysis. Odds ratios (OR) and 95% confidence intervals (95% CI) were used to evaluate the strength of associations. Results: Our meta-analysis from 33 published case-control studies showed the variant A allele of -93G>A polymorphism to be associated with increased risk in all genetic models (AA vs. GG: OR = 1.22, 95% CI: 1.03-1.44), especially among non-Asians (AA vs. GG: OR = 1.28, 95% CI: 1.04-1.58). For the I219V polymorphism, however, there was no main effect associated with overall cancer risk in any genetic model. Conclusions: The meta-analysis suggested that the MLH1 -93G>A polymorphism may be a biomarker of cancer susceptibility. Large sample association studies and assessment of gene-to-gene as well as gene-to-environment interactions are required to confirm these findings.

Molecular Characterization of Cold-Inducible β-Galactosidase from Arthrobacter sp. ON14 Isolated from Antarctica

( Xiang Xiao ),( Feng Ping Wang ),( Xu Ke ),( Xi Xiang Tang ),( Ying Bao Gai ),( Muhammad Aamer Mehmood ) 한국미생물 · 생명공학회 2011 Journal of microbiology and biotechnology Vol.21 No.3

A psychrotrophic bacterium, Arthrobacter sp. ON14, isolated from Antarctica, was shown to exhibit a high β-galactosidase activity at a low temperature. A genomic library of ON14 was constructed and screened for β-galactosidase genes on functional plates containing 5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside (X-gal) as the substrate. Two different β-galactosidase genes, named as galA, galB, were found in ON14. Computational analyses of the genes revealed that the encoded protein GalA belongs to family 2 of glycosyl hydrolysases and is a cold-active protein, whereas GalB belongs to family 42 of glycosyl hydrolysases and is a mesophilic protein. Reverse transcription analyses revealed that the expression of galA is highly induced at a low temperature (4℃) and repressed at a high temperature (28℃) when lactose is used as the sole carbon source. Conversely, the expression of galB is inhibited at a low temperature and induced at a high temperature. The purified GalA showed its peak activity at 15℃ and pH 8. The mineral ions Na+, K+, Mg2+, and Mn2+ were identified as enzyme activators, whereas Ca2+ had no influence on the enzyme activity. An enzyme stability assay revealed that the activity of GalA is significantly decreased when it is incubated at 45℃ for 2 h, and all its activity is lost when it is incubated at 50℃.

Identification of mountain-cultivated ginseng and cultivated ginseng using UPLC/oa-TOF MSE with a multivariate statistical sample-profiling strategy

Xu, Xin-fang,Cheng, Xian-long,Lin, Qing-hua,Li, Sha-sha,Jia, Zhe,Han, Ting,Lin, Rui-chao,Wang, Dan,Wei, Feng,Li, Xiang-ri The Korean Society of Ginseng 2016 Journal of Ginseng Research Vol.40 No.4

Background: Mountain-cultivated ginseng (MCG) and cultivated ginseng (CG) both belong to Panax ginseng and have similar ingredients. However, their pharmacological activities are different due to their significantly different growth environments. Methods: An ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS)-based approach was developed to distinguish MCG and CG. Multivariate statistical methods, such as principal component analysis and supervised orthogonal partial-least-squares discrimination analysis were used to select the influential components. Results: Under optimized UPLC-QTOF-MS/MS conditions, 40 ginsenosides in both MCG and CG were unambiguously identified and tentatively assigned. The results showed that the characteristic components of CG and MCG included ginsenoside Ra3/isomer, gypenoside XVII, quinquenoside R1, ginsenoside Ra7, notoginsenoside Fe, ginsenoside Ra2, ginsenoside Rs6/Rs7, malonyl ginsenoside Rc, malonyl ginsenoside Rb1, malonyl ginsenoside Rb2, palmitoleic acid, and ethyl linoleate. The malony ginsenosides are abundant in CG, but higher levels of the minor ginsenosides were detected in MCG. Conclusion: This is the first time that the differences between CG and MCG have been observed systematically at the chemical level. Our results suggested that using the identified characteristic components as chemical markers to identify different ginseng products is effective and viable.

MicroRNA-155 Expression has Prognostic Value in Patients with Non-small Cell Lung Cancer and Digestive System Carcinomas

Xu, Tong-Peng,Zhu, Can-Hong,Zhang, Jian,Xia, Rui,Wu, Feng-Lei,Han, Liang,Shen, Hua,Liu, Ling-Xiang,Shu, Yong-Qian Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.12

Objective: Published data have shown that microRNAs (miRNAs) could play a potential role as diagnostic and prognostic indicators in cancers. Data for the predictive value of microRNA-155 are inconclusive. The aim of the present analysis was therefore to evaluate the role of miR-155 in prognosis for patients with a variety of carcinomas. Methods: Relevant studies were identified by searching PubMed and EMBASE. Data were extracted from studies comparing overall survival (OS), recurrence-free survival (RFS) or cancer-specific survival (CSS) in patients with carcinoma with higher miR-155 expression and those with lower levels. The pooled hazard ratios (HRs) and 95% confidence intervals (CIs) of miR-155 for clinical outcome were calculated. Results: A total of 15 studies were included. The pooled hazard ratio (HR) for OS of higher miR-155 expression in cancerous tissue was 1.89 (95% CI: 1.20-2.99, P=0.006), which could markedly predict poorer survival in general cancer. For RFS/CSS, elevated miR-155 was also associated with poor prognosis of cancer (HR=1.50, 95% CI: 1.10-2.05, P=0.01). On subgroup analysis, the pooled HR for OS in non-small cell lung cancer (NSCLC) was 2.09 (95% CI: 0.68-6.41, P > 0.05), but for RFS/CSS was 1.28 (95% CI: 1.05-1.55, P=0.015), with statistical significance; the pooled HRs for OS and RFS/CSS in digestive system neoplasms were 3.04 (95% CI: 1.48-6.24, P=0.003) and 2.61 (95% CI: 1.98-3.42, P<0.05), respectively. Conclusions: The results indicated that the miR-155 expression level plays a prognostic role in patients with cancer, especially NSCLCs and digestive system carcinomas.

Resolution of Racemic Ketoprofen in Organic Solvents by Lipase from Burkholderia cepacia G63

Xiang-lin Zhang,Tao Liu,Li Xu,Xiaohua Gui,Feng Su,Yunjun Yan 한국생물공학회 2012 Biotechnology and Bioprocess Engineering Vol.17 No.6

A lipase from the Burkholderia cepacia strain G63 immobilized on resin was used for the resolution of ketoprofen. To study its catalytic properties in enantioselective esterication, different alcohols and solvents were tested to select the most suitable acyl acceptor and reaction medium. Compared with the low activity of the free lipase, the enzyme activity and E value of the immobilized lipase were significantly enhanced. The enantioselectivity of the immobilized lipase could also be markedly improved by adding a small amount of 18-crown-6. RSM was employed to optimize the reaction parameters. The optimal reaction conditions were: reaction time 22.50 h, additives dosage 0.4322 g (0.33 mmol/mL), and substrate molar ratio 54.11:1. Under optimal conditions, the maximal E value was up to 10.01, which exhibited a better enantioselectivity than some commercial lipases, such as Novozym 435,Lipozyme RM IM and LipozymeTL IM.