Bioaugmentation with GFP-Tagged Pseudomonas migulae AN-1 in Aniline-Contaminated Aquifer Microcosms: Cellular Responses, Survival and Effect on Indigenous Bacterial Community

( Yongsheng Zhao ),( Dan Qu ),( Rui Zhou ),( Yunge Ma ),( Hao Wang ),( Hejun Ren ) 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.5

The recently isolated aniline-degrading bacterium Pseudomonas migulae AN-1 was tagged with green fluorescent protein (GFP) to investigate its bioaugmentation potential against anilinecontaminated groundwater through microcosm experiments. The survival and cellular response of GFP-tagged AN-1 introduced in a lab-scale aquifer corresponded directly with aniline consumption. During the process, the GFP-tagged AN-1 biomass increased from 7.52 × 105 cells/ml to 128 × 105 cells/ml and the degradation rate of aniline was 6.04 mg/l/h. GFP-tagged AN-1 was moderately hydrophobic (41.74%-47.69%) when treated with 20- 100 mg/l aniline and exhibited relatively strong hydrophobicity (55.25%-65.78%) when the concentration of aniline was ≥100 mg/l. The membrane permeability of AN-1 increased followed by a rise in aniline below 100 mg/l and was invariable with aniline above 100 mg/l. Pyrosequencing analysis showed that the relative abundance of Proteobacteria (accounted for 99.22% in the non-bioaugmentation samples) changed to 89.23% after bioaugmentation with GFP-tagged AN-1. Actinobacteria increased from 0.29% to 2.01%, whereas the abundance of Firmicutes barely changed. These combined findings demonstrate the feasibility of removing aniline in aquifers by introducing the strain AN-1 and provide valuable information on the changes in the diversity of dominant populations during bioaugmentation.

Tangential Damping Model of Bolted Joint with the Physics-Based Friction Coefficient

Yongsheng Zhao,Hongchao Wu,Congbin Yang,Zhifeng Liu,Qiang Cheng 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.22 No.5

The stiff ness and damping modeling of joint surfaces are important for analyzing the dynamic characteristics of bolted joints, which has a great influence on the working precision of the machine tool. In this paper, a damping model is presented to predict the tangential damping of the joint accurately. The fractal theory is introduced to characterize the rough contact surface by using fractal dimension D and fractal roughness parameter G. For each micro-contact, the contact region can be divided into stick section and slip one. The energy dissipation of the micro-contact, which can be described as the tangential damping of bolted joint, emerges in the slip section. The physics-based friction coefficient is introduced to define the energy dissipation function based on the relationship between the deformation of micro-contact and the normal pressure. The energy dissipation factor and the proportional damping of the micro-contact can be obtained. The total tangential damping of bolted joint can be obtained by integrating the whole contact surfaces. Experimental set-up is designed to verify the proposed model. Compared with the constant friction coefficient damping model, the results show that the proposed model can more accurately describe the tangential damping of bolted joint.

Contact Stiffness Determination of High-Speed Double- Locking Toolholder-Spindle Joint based on a Macro- Micro Scale Hybrid Method

Yongsheng Zhao,Jingjing Xu,Ligang Cai,Weimin Shi,Zhifeng Liu,Qiang Cheng 한국정밀공학회 2016 International Journal of Precision Engineering and Vol.17 No.6

The stiffness of toolholder-spindle joint at high speeds plays an important role in the cutting efficiency and the machining accuracy. A double-locking toolholder (BTF type) is designed to improve the stiffness of joint. This paper presents a macro-micro scale hybrid method to determine the stiffness of double-locking toolholder-spindle joint at high speeds. In this method the finite element method and the three-dimensional fractal method are combined. It is assumed flat in macro-scale for the contact surfaces of joint. The finite element method is introduced to obtain the pressure distribution with the influence of centrifugal force at high speeds. In micro-scale, the contact surfaces are fractal featured and the three-dimensional fractal method is used to compute the stiffness based on the pressure. Experiments with BTF40-type toolholder are conducted to verify the efficiency of the proposed model in zero-speed case. The relationship between the stiffness and the technological parameters of the system can be derived based on the presented model. The upper limit of speed, the optimized range of each technological parameter are determined for obtaining the higher stiffness of joint. The results can provide theoretical basis for improving the cutting efficiency and the machining accuracy of high-speed machine tool.

A hybrid method for dynamic stiffness identification of bearing joint of high speed spindles

Yongsheng Zhao,Bingbing Zhang,Guoping An,Zhifeng Liu,Ligang Cai 국제구조공학회 2016 Structural Engineering and Mechanics, An Int'l Jou Vol.57 No.1

Bearing joint dynamic parameter identification is crucial in modeling the high speed spindles for machining centers used to predict the stability and natural frequencies of high speed spindles. In this paper, a hybrid method is proposed to identify the dynamic stiffness of bearing joint for the high speed spindles. The hybrid method refers to the analytical approach and experimental method. The support stiffness of spindle shaft can be obtained by adopting receptance coupling substructure analysis method, which consists of series connected bearing and joint stiffness. The bearing stiffness is calculated based on the Hertz contact theory. According to the proposed series stiffness equation, the stiffness of bearing joint can be separated from the composite stiffness. Then, one can obtain the bearing joint stiffness fitting formulas and its variation law under different preload. An experimental set-up with variable preload spindle is developed and the experiment is provided for the validation of presented bearing joint stiffness identification method. The results show that the bearing joint significantly cuts down the support stiffness of the spindles, which can seriously affects the dynamic characteristic of the high speed spindles.

디지털 인문학 기반의 한국어 교육과정 설계 연구―디지털 텍스트 마이닝을 중심으로

조영승 ( Zhao Yongsheng ) 중국한국(조선)어교육연구학회 2019 한국(조선)어교육연구 Vol.14 No.-

The fourth industrial revolution, centered on Big Data and artificial intelligence technology, is making a big difference in all aspects of human life including society, economy, industry, education, and medical care. However, foreign language education in universities remains mostly at traditional education levels centered on language education. In accordance with the changes of science and technology, foreign language education, which is a field of humanities, needs to realize a higher level of education beyond current education level. In this paper, we try to explore the possibility of the convergence of ‘Digital Humanities’ and Korean language education as an effective educational method for the above goals. We will consider how to integrate ‘Digital Humanities’ in traditional Korean language education centered on language education and how to design curriculum based on digital text mining through concrete examples. Korean language education, which will be improved in the future, it is aimed not only for linguistic and humanistic thinking ability for new digital generation, but also for ‘Digital Thinking’ ability which is suitable for the fourth industrial revolution.

Internal Mammary Sentinel Lymph Node Biopsy after Neoadjuvant Chemotherapy in Breast Cancer

Zhao Bi,Peng Chen,Jingjing Liu,Yanbing Liu,Pengfei Qiu,Qifeng Yang,Weizhen Zheng,Yongsheng Wang 한국유방암학회 2018 Journal of breast cancer Vol.21 No.4

Purpose: The definition of nodal pathologic complete response (pCR) after a neoadjuvant chemotherapy (NAC) just included the evaluation of axillary lymph node (ALN) without internal mammary lymph node. This study aimed to evaluate the feasibility of internal mammary-sentinel lymph node biopsy (IM-SLNB) in patients with breast cancer who underwent NAC. Methods: From November 2011 to 2017, 179 patients with primary breast cancer who underwent operation after NAC were included in this study. All patients received radiotracer injection with modified injection technology. IM-SLNB would be performed on patients with internal mammary sentinel lymph node (IMSLN) visualization. Results: Among the 158 patients with cN+ disease, the rate of nodal pCR was 36.1% (57/158). Among the 179 patients, the visualization rate of IMSLN was 31.8% (57/179) and was 12.3% (7/57) and 87.7% (50/57) among those with cN0 and cN+ disease, respectively. Furthermore, the detection rate of IMSLN was 31.3% (56/179). The success rate of IM-SLNB was 98.2% (56/57). The IMSLN metastasis rate was 7.1% (4/56), and all of them were accompanied by ALN metastasis. The number of positive ALNs in patients with IMSLN metastasis was 3, 6, 8, and 9. The pathology nodal stage had been changed from pN1/ pN2 to pN3b. The pathology stage had been changed from IIA/ IIIA to IIIC. Conclusion: Patients with visualization of IMSLN should perform IM-SLNB after NAC, especially for patients with cN+ disease, in order to complete lymph nodal staging. IM-SLNB could further improve the definition of nodal pCR and guide the internal mammary node irradiation.

The Construction of Emergency Logistics and Integrated Transport System Based on “Scenario-Response” Mode

Yu Zhao,Yongsheng Qian 보안공학연구지원센터 2014 International Journal of Control and Automation Vol.7 No.3

보행 로봇의 충격 흡수를 위한 아치형 발의 설계

성상학,Yongsheng Zhao,염영일 제어로봇시스템학회 2009 제어로봇시스템학회 국내학술대회 논문집 Vol.2009 No.9

Shock absorption of impact force in legged locomotion is a critical problem for posture stabilization. Especially in robot running, shock absorption ability of foot determines overall motion stability. In human case, motion stability is achieved through whole body motion, shock absorbing material and foot structure, etc. This paper presents arch-structure foot which utilizes human foot arch-structure. Impact force during locomotion is reduced by change in arch structure. Shock absorbing function of developed foot is validated through simulation and experiment.

Effect of heat treatment on the crystallization toughening of tailing-derived glass-ceramics

Du Yongsheng,Yang Xiaowei,Zhang Hongxia,Zhang Xuefeng,Zhao Ming,Chen Hua,Ouyang Shunli,Li Baowei 한양대학교 세라믹연구소 2016 Journal of Ceramic Processing Research Vol.17 No.12

The effect of heat treatment to a parent glass of the composition CaO-MgO-Al2O3-SiO2 (CMAS) on the course ofcrystallization and properties of the Bayan Obo east mine tailing glass-ceramics is examined. The crystallization behavior,phase composition, morphology and structure of glass-ceramics are characterized. The results indicate that the phases formedin the glass-ceramics are augite and the initial nucleation phases are magnetite, which can be proved by differential scanningcalorimetry (DSC), X-ray diffraction (XRD) and scanning transmission electron microscope (STEM). Heat treatment plays asignificant role in improving the crystallization process, fracture characteristics, modulus and bending strength. All of theseproperties reach a maximum for the fully crystallized glass-ceramic. Scanning electron microscope (SEM) and atomic forcemicroscope (AFM) are used to reveal the topography of the fracture surfaces. The intergranular fracture can be observed onthe fracture surface.

EFFECT OF REACTION TIME ON MICROSTRUCTURE, DIELECTRIC PROPERTY AND MICROWAVE ABSORPTION PROPERTY OF Cu-DOPED SiC NANOPOWDER

XIAOLEI SU,YONGSHENG TAN,YAN JIA,KAILI ZHAO,SONGTAO LIU,XINHAI HE,CHONG FU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.2

Cu-doped SiC nanopowders have been prepared via combustion synthesis of the silicon andcarbon system in a 0.1 MPa nitrogen atmosphere under di®erent reaction time, using copper asthe dopant and PTFE as the chemical activator, respectively. X-ray di®raction, scanning elec-tronic microscope and Raman spectra have been used to characterize the phase and morphologyof prepared nanopowders. Results indicate that the lattice constant of prepared Cu-doped SiCnanopowder decreases with extending reaction time. The prepared nanopowders have ¯nespherical particles and narrow particle size distribution and the particle size increases withincreasing reaction time. The electric permittivities of prepared Cu-doped SiC nanopowders inthe frequency range of 8.2 – 12.4 GHz have been determined. The real part " 0, imaginary part " 00and dielectric loss tg ? of complex permittivity decrease with increasing reaction time. All pre-pared Cu-doped SiC nanopowder exhibits good microwave absorption property in the frequencyrange of 8.2 – 12.4 GHz.