Bridging theory and practice: participatory planning in China

Zhihua Zhou 서울시립대학교 도시과학연구원 2018 도시과학국제저널 Vol.22 No.3

Polyurethane Membrane with Temperature- and pH-Controllable Permeability for Amino-Acids

Hu Zhou,Ruiping Xun,Kejian Wu,Zhihua Zhou,Bin Yu,Youxin Tang,Ning Li 한국고분자학회 2015 Macromolecular Research Vol.23 No.1

This work was focused on the investigation of the temperature- and pH-responsive polyurethane (PU)membranes and their permeability to amino-acids in response to environmental stimuli. The PU membrane wasprepared from a wet phase inversion method and a two-step solution polymerization from polycaprolactone diols(PCL), 4,4′-diphenylmethane diisocyanate (MDI), dimethylol propionic acid (DMPA), etc. The chemical structure,phase state, morphology and surface wettability of the membrane were characterized with Fourier transform infrared(FTIR) spectrometer, differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and contactangle tester, respectively. The temperature and pH responses of the membrane were investigated by means of anamino-acid permeate experiment. The L-phenylalanine (L-Phe) was chosen as model amino-acids. The permeation of theL-Phe was measured using a dead-end flow filtration at varied temperatures and pH, and characterized by the permeateflux (J) and rejection coefficient (R). J of the L-Phe across the PU membrane increased with increasingtemperature and showed a sharp increase when temperature was raised to the crystalline melting temperature (Tm)of the soft segment of PU, while decreased with increasing pH and having a sharp decrease when pH reached thedissociation constant (pKa) of DMPA contained in PU macromolecules. While, the R behavior of L-Phe was justopposite from the results of J, which decreased with increasing temperature and increased with increasing pH,also showing the temperature and pH responses. Hopefully, the PU membrane with temperature- and pH-controllablepermeability has promising prospects in water treatment, membrane separation, drug delivery system, etc.

A Location Context Awareness Personalized Mobile Service Prediction Model and it's Algorithm : Design and Implementation

Minjun Xin,Liyuan Zhou,Han Cao,Zhihua Niu 보안공학연구지원센터 2014 International Journal of Grid and Distributed Comp Vol.7 No.6

With the expansion of mobile Internet, location-based services have become a hot spot in Internet industry. To improve the accuracy and efficiency of the location-based services discovery, researchers in web services recommendation area are still busy looking for method. In this paper, it proposes a LCAMSP model (Location Context Awareness Mobile Service Prediction, LCAMSP) under mobile Internet environment, aims to meet the exact personal requirements of users’ current location and preference. Then, the similar users’ grouping is also a important thread to predict the continuous movement for mobile users. Because each user has own preference, a dynamic calculation function for the weight of each attribute is discussed in this paper. Finally, taking the hotel reservation service as an example, a verification algorithm will be applied to measure the performance of LCAMSP method. With the premise of increasing limited time, the accuracy of LCAMSP algorithm is significantly improved under the mobile service environment.

The Research of Physical Education Reform in Chinese university in the Context of New Normal

( Jianmei Zhou ),( Zhihua Zhang ) 한국체육학회 2015 국제스포츠과학 학술대회 Vol.2015 No.1

Research purpose: Since the 18th CPC National Congress, China`s economy, politics, culture, society, ecology and other fields all have showing the "new normal". In the context of "new normal", Physical education should not force, but to guide; not indoctrinate, but to influence; not transform, but to change. This study examined the reform of physical education in Chinese university from a whole new perspective, providing evidence to improve physical teaching quality and facilitate the universities to focus on the internal development and scientific development and playing a significant role in accelerating the overall and sustainable reform of physical education in university. Research method: The main research methods used in this study are literature, expert interview, questionnaire, field investigation. Results: The main task of top universities is to cultivate talents with all-round development of morality, intelligence physique and aesthetic. "Promoting the overall development of students" is the trend of physical education in university. Universities should insist on the principle of comprehensive education, regard the health first, all-round development and lifelong physical ideas as a starting point, and keep improving the physical teaching throughout the physical education reform. The innovation of physical education system is both a starting point and the first imperative of physical education reform. In the process of education reform, universities should teach students in accordance with their aptitude, constantly adjust the content and framework of physical education curriculum. Universities should be student-centered and teacher-led, strengthen the research of teaching objectives, teaching content, teaching methods and teaching conditions, promote for innovation and gradually construct a teaching model featured by each university`s characteristic and teaching style. A diverse and dynamic evaluation system should be established, which fully reflects students` individual differences, emphasizes the teaching process, evaluation as well as students` overall development. Conclusion: Universities should adhere to the people-oriented principle; optimize curriculum structure; reform teaching content and teaching mode; establish a sound scientific teaching evaluation system; recognize individual differences of students; reform and build physical education system which fits for the overall development of students . In the context of "new normal", Physical education reform in university should put students first; focus on improving the quality of teaching and constantly optimize the system of physical education curriculum; emphasize on students` personality, and explore the new model of physical education in university, organization and management; stress teaching evaluation and gradually improve the diversification of evaluation system of physical education in university.

Activation of β2-Adrenergic Receptor Promotes Growth and Angiogenesis in Breast Cancer by Down-regulating PPARγ

Jing Zhou,Zhanzhao Liu,Lingjing Zhang,Xiao Hu,Zhihua Wang,Hong Ni,Yue Wang,Jun-fang Qin 대한암학회 2020 Cancer Research and Treatment Vol.52 No.3

Purpose Chronic stress and related hormones are key in cancer progression. Peroxisome proliferator- activated receptor ! (PPAR!) and its agonists was reported that inducing anti-tumor effect. However, the function of PPAR! in pro-tumorigenic effects induced by chronic stress in breast cancer remains unknown. Herein, we have characterized a novel role of PPAR! and vascular endothelial growth factor (VEGF)/fibroblast growth factor 2 (FGF2) signals in breast cancer promoted by chronic stress. Materials and Methods We performed experiments in vivo and in vitro and used bioinformatics data to evaluate the therapeutic potential of PPAR! in breast cancer promoted by stress. Results Chronic stress significantly inhibited the PPAR! expression and promoted breast cancer in vivo. VEGF/FGF2-mediated angiogenesis increased in the chronic stress group compared to the control group. PPAR! agonist pioglitazone (PioG) injection offset the pro-tumorigenic effect of chronic stress. Moreover, specific "2-adrenergic receptor ("2R) antagonist ICI11- 8551 inhibited the effect of chronic stress. In vitro, norepinephrine (NE) treatment had a similar tendency to chronic stress. The effect of NE was mediated by the "2R/adenylate cyclase signaling pathway and suppressed by PioG. PPAR! suppressed VEGF/FGF2 through reactive oxygen species inhibition. Bioinformatics data confirmed that there was a low PPAR! expression in breast invasive carcinoma. Lower PPAR! was associated with a significantly worse survival. Conclusion "2R activation induced by chronic stress and related hormones promotes growth and VEGF/ FGF2-mediated angiogenesis of breast cancer by down-regulating PPAR!. Our findings hint that " receptor and PPAR! as two target molecules and the novel role for their agonists or antagonists as clinical medicine in breast cancer therapy.

Global seismic damage assessment of high-rise hybrid structures

Xilin Lu,Zhihua Huang,Ying Zhou 사단법인 한국계산역학회 2011 Computers and Concrete, An International Journal Vol.8 No.3

Nowadays, many engineers believe that hybrid structures with reinforced concrete central core walls and perimeter steel frames offer an economical method to develop the strength and stiffness required for seismic design. As a result, a variety of such structures have recently been applied in actual construction. However, the performance-based seismic design of such structures has not been investigated systematically. In the performance-based seismic design, quantifying the seismic damage of complete structures by damage indices is one of the fundamental issues. Four damage states and the final softening index at each state for high-rise hybrid structures are suggested firstly in this paper. Based on nonlinear dynamic analysis, the relation of the maximum inter-story drift, the main structural characteristics, and the final softening index is obtained. At the same time, the relation between the maximum inter-story drift and the maximum roof displacement over the height is also acquired. A double-variable index accounting for maximum deformation and cumulative energy is put forward based on the pushover analysis. Finally, a case study is conducted on a high-rise hybrid structure model tested on shaking table before to verify the suggested quantities of damage indices.

Optimal of black anti-static AZO/Al2O3-SiO2-VxOy coatings for spacecraft stray light on high silicon aluminum alloys

Li Zhenyu,Zhou Zhihua,Wang Qun,Lu Songtao 한국물리학회 2023 Current Applied Physics Vol.55 No.-

It is still challenging to prepare an anti-static and anti-stray astigmatism coating on the high silicon aluminum alloy (>50 wt% Si, Al-50Si) for space material under extreme environments. To address these issues, the black anti-stray light coating with enhanced conductivity on the chemical etching surface of high-silicon Al-70Si alloy were successfully fabricated by the combination of plasma electrolytic oxidation (PEO) technology and deposited aluminum doped zinc oxide (AZO) transparent conductive film by magnetron sputtering technology. The microstructures, phase, elemental compositions, light absorption performance and electrical resistivity of coatings were tested and analyzed by SEM, EDS, XRD and XPS spectroscopy. The effects of process parameters including current density and AZO sputtering times on the structure, optical and electrical properties of the film layer were systematically studied. Convection through the fixation effect in the etched Al-70Si alloy porous layer promoted the internal heat and mass transfer during PEO process which is similar to previous reported mechanism of filling of cracks and pores by nanoparticles leading to the layer densification. The PEO coating had the highest absorptivity of 0.946 and it only decreased to 0.939 after AZO sputtering, at the same time the coating has the lowest resistivity of 1.04 × 107 Ω/sq, indicating excellent anti-stray light and antistatic ability. This two-step route pave the way to improve the conductivity without compromising optical properties of PEO coating on the high silicon aluminum alloy (>50 wt% Si, Al-50Si) for space material.

A fourth-order accurate alternating group explicit parallel algorithm for the convection-diffusion equation

Jianguo LIN,Zhihua XIE,Juntao ZHOU 한국전산유체공학회 2006 한국전산유체공학회 학술대회논문집 Vol.2006 No.5

Numerical and experimental investigation on the temperature distribution of steel tubes under solar radiation

Hongbo Liu,Zhihua Chen,Ting Zhou 국제구조공학회 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.43 No.6

The temperature on steel structures is larger than the ambient air temperature under solar radiation and the temperature distribution on the affected structure is non-uniform and complicated. The steel tube, as a main structural member, has been investigated through experiment and numerical analysis. In this study, the temperature distribution on a properly designed steel tube under solar radiation is measured. A finite element transient thermal analysis method is presented and verified by the experimental results and a series of parametric studies are carried out to investigate the influence of various geometric properties and orientation on the temperature distribution. Furthermore, a simplified approach is proposed to predict the temperature distribution of steel tube. Based on both the experimental and the numerical results, it is concluded that the solar radiation has a significant effect on the temperature distribution of steel tubes. Under the solar radiation, the temperature of steel tubes is about 20.6oC higher than the ambient air temperature. The temperature distribution of steel tubes is sensitive to the steel solar radiation absorption, steel tube diameter and orientation, but insensitive to the solar radiation reflectance and thickness of steel tube.

Fractional-N Frequency Synthesis: Overview and Practical Aspects with FIR-Embedded Design

Rhee, Woogeun,Xu, Ni,Zhou, Bo,Wang, Zhihua The Institute of Electronics and Information Engin 2013 Journal of semiconductor technology and science Vol.13 No.2

This paper gives an overview of fractional-N phase-locked loops (PLLs) with practical design perspectives focusing on a ${\Delta}{\Sigma}$ modulation technique and a finite-impulse response (FIR) filtering method. Spur generation and nonlinearity issues in the ${\Delta}{\Sigma}$ fractional-N PLLs are discussed with simulation and hardware results. High-order ${\Delta}{\Sigma}$ modulation with FIR-embedded filtering is considered for low noise frequency generation. Also, various architectures of finite-modulo fractional-N PLLs are reviewed for alternative low cost design, and the FIR filtering technique is shown to be useful for spur reduction in the finite-modulo fractional-N PLL design.