Orthogonality Correction for Concentric Tri-axis Fluxgate Magnetometer

Xuan Thang Trinh,Jen-Tzong Jeng,Chih-Cheng Lu,Van Su Luong 한국자기학회 2019 Journal of Magnetics Vol.24 No.2

In this work, a compact tri-axis fluxgate magnetometer comprising a single magnetic core was implemented and the effectiveness of the orthogonality correction algorithm was demonstrated. The vector magnetometer consists of a tube-shaped soft magnetic flux chopper with a toroidal coil and three concentric pick-up coils. The tube-shaped flux chopper with magnet wires has the total dimension of 10 mm × 10 mm. The number of turns of the pick-up coils X-, Y-, and Z- are 110, 110 and 150, respectively. The center of flux chopper is also the geometric center of the three pick-up coils, of which the sensing directions are aligned along the Cartesian axes. The concentric design ensures a single field point for the three sensing axes. When using the tri-axis fluxgate magnetometer as an electronic compass, the geomagnetic field components converted from the demodulated outputs of the sensing coils shows high accuracy by using the voltage-to-field transfer matrix. The proposed fluxgate system is suitable for applications related to high-accuracy static magnetic field measurement, e.g. geomagnetic field monitoring, electronic compass, and magnetic field mapping.

Theoretical and experimental investigations of gear transmission with geometric elements constructed tooth pairs having triple contact points

Lu-he Zhang,Shi-xuan Li,Jian Huang,Bingkui Chen 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.7

A novel gear transmission with geometric elements constructed tooth pairs having triple contact points is proposed in this study. Based on the equidistance enveloping method, the generation principle and method of the tooth surface are presented. Three types of contact pattern of tooth profiles are generated: convex to convex, convex to plane, convex to concave. A calculation example for convex to concave tooth profiles of gears is provided. Performance experiment is carried out based on the developed gear prototype, and a comparison with involute gear drive is also shown. Theoretical and numerical results demonstrate the feasibility and correctness and it lays the foundation for the design of high performance gear transmission.

Hysteretic performance of the all-steel buckling-restrained brace with LY315 steel core

Xuan Wei,Lu Yang,Yohchia Frank Chen,Meng Wang 국제구조공학회 2022 Steel and Composite Structures, An International J Vol.44 No.6

To study the seismic performance of the all-steel buckling-restrained brace (BRB) using the novel soft steel LY315 for core member, a total of three identical BRBs were designed and a series of experimental and numerical studies were conducted. First, monotonic and cyclic loading tests were carried out to obtain the mechanical properties of LY315 steel. In addition, the parameters of the Chaboche model were calibrated based on the test results and then verified using ABAQUS. Second, three BRB specimens were tested under cyclic loads to investigate the seismic performance. The failure modes of all the specimens were identified and discussed. The test results indicate that the BRBs exhibit excellent energy dissipation capacity, good ductility, and excellent low-cycle fatigue performance. Then, a finite element (FE) model was established and verified with the test results. Furthermore, a parametric study was performed to further investigate the effects of gap size, restraining ratio, slenderness ratio of the yielding segment, and material properties of the core member on the load capacity and energy dissipation capacity of BRBs.

The Relationship Between Preoperative Cervical Sagittal Balance and Clinical Outcome of Patients With Hirayama Disease Treated With Anterior Cervical Discectomy and Fusion

Xiao Lu,Guang-Yu Xu,Cong Nie,Yu Xuan Zhang,Jian Song,Jianyuan Jiang 대한척추신경외과학회 2021 Neurospine Vol.18 No.3

Objective: Anterior cervical discectomy and fusion (ACDF) is a common surgical method used to treat patients with Hirayama disease. And sagittal balance indexes have been revealed to be predictors of clinical outcomes in patients with cervical diseases, but their relationships with ACDF-treated Hirayama disease outcomes remain unknown. The purpose of this study is to evaluate the relationship of preoperative cervical sagittal balance indexes and clinical outcomes in ACDF-treated Hirayama disease patients. Methods: Eighty patients with Hirayama disease treated by ACDF were reviewed retrospectively. Six cervical sagittal balance parameters were collected including Cobb angle, T1 slope, C1–7 sagittal vertical axis (SVA), C2–7 SVA, center of gravity of the head (CGH)-C7 SVA, range of motion. The recovery outcomes of the patients were divided into 2 groups by Odom score and the differences in recovery between the 2 groups were confirmed by electromyography. The correlation between imaging parameters and postoperative outcome was evaluated with logistic regression. The receiver operating characteristic (ROC) curve and area under the ROC curve (AUC) were used to evaluate the significant result of logistic regression and the optimal diagnostic value. Results: Only 2 parameters, Cobb angle and CGH-C7 SVA, showed statistical correlation with the postoperative outcome assessment by logistic regression. AUC of Cobb angle and CGH-C7 SVA were 0.559 and 0.702 respectively. The optimal predictive threshold was 1.50° and 5.40 mm, respectively. Conclusion: A larger Cobb angle and smaller CGH-C7 SVA seemed to correlate with a better postoperative outcome. These 2 factors could be used to predict the outcome of surgical treatment of Hirayama disease preoperatively.

Limited Diagnostic Value of microRNAs for Detecting Colorectal Cancer: A Meta-analysis

Zhou, Xuan-Jun,Dong, Zhao-Gang,Yang, Yong-Mei,Du, Lu-Tao,Zhang, Xin,Wang, Chuan-Xin Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.8

Background: MicroRNAs have been demonstrated to play important roles in the development and progression of colorectal cancer. Several studies utilizing microRNAs as diagnostic biomarkers for colorectal cancer (CRC) have been reported. The aim of this meta-analysis was to comprehensively and quantitatively summarize the diagnostic value of microRNAs for detecting colorectal cancer. Methods: We searched PubMed, Embase and Cochrane Library for published studies that used microRNAs as biomarkers for the diagnosis of colorectal cancer. Summary estimates for sensitivity, specificity and other measures of accuracy of microRNAs in the diagnosis of colorectal cancer were calculated using the bivariate random effects model. A summary receiver operating characteristic (SROC) curve was also generated to summarize the overall effectiveness of the test. Result: Thirteen studies from twelve published articles met the inclusion criteria and were included. The overall sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odd ratio of microRNAs for the diagnosis of colorectal cancer were 0.81 (95%CI: 0.79-0.84), 0.78 (95%CI: 0.75-0.82), 4.14 (95%CI: 2.90-5.92), 0.24 (95%CI: 0.19-0.30), and 19.2 (95%CI: 11.7-31.5), respectively. The area under the SROC curve was 0.89. Conclusions: The current evidence suggests that the microRNAs test might not be used alone as a screening tool for CRC. Combining microRNAs testing with other conventional tests such as FOBT may improve the diagnostic accuracy for detecting CRC.

Methylation Status of Transcriptional Modulatory Genes Associated with Colorectal Cancer in Northeast China

Han-Lu Gao,Xuan Wang,Hong-Ru Sun,Jun-De Zhou,Shang-Qun Lin,Yu-Hang Xing,Lin Zhu,Hai-Bo Zhou,Ya-Shuang Zhao,Qiang Chi,Yu-Peng Liu 거트앤리버 소화기연관학회협의회 2018 Gut and Liver Vol.12 No.2

Background/Aims: Methylation status plays a causal role in carcinogenesis in targeted tissues. However, the relationship between the DNA methylation status of multiple genes in blood leukocytes and colorectal cancer (CRC) susceptibility as well as interactions between dietary factors and CRC risks are unclear. Methods: We performed a case-control study with 466 CRC patients and 507 cancer-free controls to investigate the association among the methylation status of individual genes, multiple CpG site methylation (MCSM), multiple CpG site heterogeneous methylation and CRC susceptibility. Peripheral blood DNA methylation levels were detected by performing methylation-sensitive high-resolution melting. Results: Total heterogeneous methylation of CA10 and WT1 conferred a significantly higher risk of CRC (adjusted odds ratio [ORadjusted], 5.445; 95% confidence interval [CI], 3.075 to 9.643; ORadjusted, 1.831; 95% CI, 1.100 to 3.047; respectively). Subjects with high-level MCSM (MCSM-H) status demonstrated a higher risk of CRC (ORadjusted, 4.318; 95% CI, 1.529 to 12.197). Additionally, interactions between the high-level intake of fruit and CRH, WT1, and MCSM on CRC were statistically significant. Conclusions: The gene methylation status of blood leukocytes may be associated with CRC risk. MCSM-H of blood leukocytes was associated with CRC, especially in younger people. Some dietary factors may affect hypermethylation status and influence susceptibility to CRC.

Meshing performance investigations of involute worm and helical gear drive based on counterpart rack

Binbin Lu,Yonghong Chen,Shi-xuan Li,Bingkui Chen 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.8

Due to the involute worm and helical gear drive is different from the parallel shaft helical gear drive and the worm drive, the plane meshing theory and the space enveloping principle cannot be directly applied for this worm drive when the meshing analysis is performed, there has been no good analysis method to accurately calculate the meshing situation. To satisfy the increasing requirements of low-noise and long-lifetime in the service robots and the modern intelligent house systems, especially the intelligent shading system in the modern intelligent house system, a novel meshing performance analysis method is proposed for the involute worm and helical gear drive based on the counterpart rack. By calculating the contact line between the counterpart rack and helical gear and the contact line between the counterpart rack and involute worm, we can get the contact point of involute worm and helical gear finally. This novel meshing performance analysis makes it possible to use the plane meshing theory and the space enveloping principle to analyze involute worm and helical gear drive. The meshing relationship between the involute worm and the counterpart rack, as well as the counterpart rack and the helical gear are presented, and the computational model of contact ratio and contact ellipse are obtained through the counterpart rack. The mathematic model for the instantaneous contact point and contacts trace of the worm drive with different assembly errors is established, and the meshing performances are investigated through the numerical analysis, simulation analysis and performance testing. The results show that this worm drive is insensitively to the assembly errors, and it is beneficial for reducing the vibrationnoise and extending the service life. This theoretical research provides theoretical support for further optimizing the vibration and noise of involute worm and helical gear drive and improving the fatigue life.

The Effect of Investing into Distribution Information and Communication Technologies on Banking Performance the Empirical Evidence from an Emerging Country

PHAN Anh,LU Chi Huu,HOANG Lam Xuan,NGUYEN Phuong Minh 한국유통과학회 2022 유통과학연구 Vol.20 No.6

Purpose: This study aims to investigate the impact of investing into technology development on banking performance in an emerging country. Research design, data and methodology: Based on the data of 12 commercial banks listed in Vietnam from 2011 to 2019 and performing multivariable regression analyses as well as conducting a variety of robustness tests, we carry out the empirical investigation to discover this impact. Results: Our empirical evidence shows that these spending help to improve significantly performance of banks. Particularly, the technology expenditures have positive effect on the net interest margin and the non-interest income in which the level of influence on the latter is relatively remarkable in comparison with the former. At the same time, the result does not support the view that increasingly spending on technology may lead banks to face the risk of instability. Conclusions: Overall, our empirical analysis indicates that increasing investment into distribution information and communication technologies will help to enhance business strategies of banks and thus we advocate the bright side of technology development and digitalization in banking sector. We believe that the research is useful for both managers, regulators and policy makers in Vietnam as well as in countries having similar financial structure.

中國老齡化問題應對策略研究:集體社會資本視角下的老年人力資源開發

姜萱(Jiang, Xuan),陸競姸(Lu, Jing-yan),金紅花(Jin, Hong-hua),吳偉澤(Wu, Wei-ze) 동아인문학회 2021 동아인문학 Vol.57 No.-

인구의 고령화는 경제발전과 기술진보의 산물이자 삶의 질을 추구하는 인류의 필연적인 결과이다. 이 세계적인 난제를 해결하기 위해서는 인류 공통의 지혜가 필요하다. 중국은 2000년에 인구 고령화 국가 대열에 합류하여 현재는 거의 중등 고령화 수준에 도달했고, “부유해 지기 전의 고령화”, 급속한 고령화, 대규모 고령화의 특징을 보이고 있다. 인구 고령화는 미래 세계에서 영구적인 모습이 될 가능성이 높기 때문에 경제사회의 발전을 위해서는 노인인적자원 활용과 노인 수요 충족에 중점을 두어야 한다. 따라서 노인인적자원개발 사업이 중국의 현 인구 고령화 문제를 해결하는데 기여할 수 있을 것이라 판단된다. 본 연구는 Coleman의 집단의 사회적 자본 개념과 거시적 차원의 사회적 자본 이론을 기반으로 하였으며, 노인인적자원개발의 다자이익 집단은 사회개발, 조직개발, 자기개발의 세 가지 유형으로 구분하였다. 또한 중국의 고령화 현황과 노인인적자원개발의 전제 조건, 미래에 직면할 도전에 대하여 체계적으로 분석하고, 이를 바탕으로 최종적으로 중국의 실정에 맞는 인구 고령화 문제에 대한 해결책을 알아보았다. 본 연구의 목적은 다자이익집단이 함께 참여하여 사회적 자본을 모으고, 시너지 효과를 형성하여 인구 고령화 문제가 가져올 부정적인 결과를 완화하는데 있다. Population aging is the product of economic development and technological progress, as well as the inevitable result of human"s pursuit of high quality of life,which requires the common wisdom of human beings to solve this worldwide problem. China entered the ranks of population aging countries in 2000, and has now reached the aged society, and is characterized by “getting old before getting rich” problem, rapid population aging, and a large-scale elderly population. Since population aging has become an irreversible trend and is likely to become a permanent norm in the future all over the world, economic and social development needs to be closely promoted around the utilization of the elderly human resources and meeting their needs. Therefore, this paper advocates the development of the elderly human resources business as a means to solve the current problem of population aging in China. Based on Coleman"s concept of collective social capital and macro-level social capital theory, this paper classifies the multi-stakeholders in developing elderly human resources into three types: social development, organizational development and self-development. Through this, the paper makes a systematic analysis on the current situation of population aging in China, as well as the preconditions and future challenges of developing elderly human resources. Finally, the paper has constructed a set of solutions to the population aging problem in line with China"s national conditions. The purpose of this paper is to realize the use of multistakeholder groups to participate together, gather social capital and form a synergy to alleviate the adverse consequences of population aging. Findings are as follows: (1) in terms of social development, China should make full preparations under the national strategic framework by taking advantage of the “14th five-year plan” time window period, improve the policy system of elderly human resources development, improve the differences in the degree of aging in different regions according to local conditions, innovate ideas, and encourage high-quality elderly people to return to the labor market. (2) In terms of organizational development, it is necessary to improve the specialization and professionalism of the intermediary services of the elderly labor, break the organizational boundaries of communities. The paper suggests that educational organizations establish lifelong education and training systems, and that enterprises implement flexible management of the elderly human resources. (3) In terms of self-development, both the awareness of selfdevelopment and behavioral change of the elderly should be promoted. We should not only improve the awareness of re-employment and self-learning, but also making full use of the leading role of high-quality elderly human resources. So as to improve more elderly people to integrate into the elderly life with higher social value.

Over-expression of FaGalLDH Increases Ascorbic Acid Concentrations and Enhances Salt Stress Tolerance in Arabidopsis thaliana

Dun Wanwan,Wei Xuan,Wang Lu,Liu Jingjing,Zhao Jing,Sun Peipei,Fang Congbing,Xie Xingbin 한국식물학회 2023 Journal of Plant Biology Vol.66 No.1

The strawberry (Fragaria×ananassa) is an economically important perennial crop plant, and its fruits are rich in vitamin C (l-ascorbic acid [AsA]) and other nutrients. l-galactono-1,4-lactone dehydrogenase (GalLDH) is a key enzyme in the terminal step of AsA biosynthesis pathway in plants. Here, the GalLDH gene (FaGalLDH) was cloned from ‘Benihoppe’ strawberries. AsA content increased during fruit development and peaked at the red-ripening stage, and AsA concentrations in diferent tissues were correlated with enzyme activity and transcription level of FaGalLDH. Transient over-expression of FaGalLDH in strawberry fruit increased its overall expression and AsA production signifcantly, whereas transient RNAi of FaGalLDH decreased its expression and AsA content. Furthermore, the optimum pH and temperature for FaGalLDH activity were 8.0 and 25 °C, respectively. Ectopic expression of the FaGalLDH gene in Arabidopsis resulted in higher AsA content and enzyme activity in transgenic lines than in wild-type plants. FaGalLDH over-expression resulted in enhanced tolerance to salt stress due to reduced accumulation of malondialdehyde, H2O2, and O2 .−, as well as higher survival rates, root length, proline content, and superoxide dismutase, peroxidase, and catalase activities. These results provide useful information regarding AsA biosynthesis and salt tolerance, which may help to improve strawberry fruit quality and productivity.