Polyacrylonitrile mesoporous composite membranes with high separation efficiency prepared by fast freeze-extraction process

Ruixue Lv,Faizal Soyekwo,Qiugen Zhang,Runsheng Gao,Jianyang Wu,Yan Qu,Aimei Zhu,Qinglin Liu 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.49 No.-

Polymer mesoporous membranes are widely employed in many membrane processes includingultrafiltration and dialysis, and become more crucial with increasing demand in chemical and lifefields. Here we report a highly-efficient polymer membrane with sub-5 nm pores and highflux frompolyacrylonitrile (PAN) nanoparticles produced from dilute PAN solution via fast freeze-extractionprocess. The25 nm-size PAN nanoparticles forming brad-like chains are dispersed in ethanol solutionand used to prepare the membrane byfiltration-assisted assembly method across a macroporoussupport. Effects of solvents and usage of PAN on membrane formation is studied in detail. The resultantmembranes comprise of the nanoparticles stacked on the support to form a mesoporous separation layerwith a controllable thickness and a cut-off of below 5 nm. They exhibit excellent separation performancesin ultrafiltration of protein and nanoparticle solutions. Typically, the membrane with 94.6% rejection of5 nm gold nanoparticles has a pure waterflux of 823 L m 1 h 1 bar 1 and perfect rejection for ferritinmolecules and 10 nm gold nanoparticles. The newly developed membranes should have wide applicationin chemical, environment and lifefields.

A Large Scale Multi-Stage Switching System with Low Resequence Delay

Ruixue Fan,Toshiya Aramaki,Hieoshi Suzuki,Takao Takeuchi 대한전자공학회 1992 JC-CNSS : Joint Conference on Communications, Netw Vol.5 No.-

Effect of CeO2 addition on crystallization and thermophysical properties of Li2O-ZnO-SiO2 glass-ceramics

Ruixue Li,Qian Zhang,Xingliang Peng,Weizhen Liu 한양대학교 세라믹연구소 2020 Journal of Ceramic Processing Research Vol.21 No.1

The effect of CeO2 addition on crystallization and thermo-physical properties of lithium zinc silicate (LZS) glasses containingLi2O-ZnO-SiO2-Al2O3-Na2O-P2O5 was investigated. The changes of CeO2 contents (2-8 wt.%) had an obvious influence on thetransition temperatures (Tg) and crystallization temperatures (Tc) of LZS glass-ceramics, and they increased with CeO2 contentincreasing. According to XRD analysis, CeO2 promoted the formation of cristobalite and β-spodumene crystals, and β-spodumene increased obviously. As the CeO2 content increasing, the microstructure and microhardness (being 6.88 Gpa at 880oC) of glass-ceramics had great changes. The average thermal expansion coefficient (20 - 450 oC) showed first increasing thendecreasing, having a wide range. The maximum of thermal expansion coefficient was obtained when the glass-ceramicscontained 4 wt.% CeO2, being 175×10−7 K−1 (at 700 oC) and 178×10−7 K−1 (at 880 oC) respectively. Excellent thermo-physicalproperties indicate the glass has greater potential application, such as being used as sealing glass.

Effect of Bypass Ratio on Optimal Fan Outer Pressure Ratio and Performance for Turbofan Engines

Ruixue Zhang,Jun Jiang,Anthony Jackson 한국항공우주학회 2019 International Journal of Aeronautical and Space Sc Vol.20 No.1

This study was carried out to explore the effect of bypass ratio on optimal fan outer pressure ratio and the performance of turbofan engine with the same engine core. The member of Rolls-Royce Trent family, Trent-XWB, is chosen as the baseline engine. Based on the published data, a model for the simulation of engine performance was set up. Then, a series of engine models with different bypass ratios were established based on the same Trent-XWB engine core and the way to get optimal fan outer pressure ratio was derived. It was concluded that for the fixed engine core, when the bypass ratio was chosen, there would be one optimal outer pressure ratio existing which could make the thrust maximum and the specific fuel consumption reach minimum. By comparing the performance of the turbofan engines with different bypass ratios, it shows that the increase of bypass ratio results in higher thrust and lower specific fuel consumption. However, the additional cost like the increase of both drag and weight needs to be taken into account at the preliminary design stage in practice.

상호작용성과 관계품질이 라이브 스트리밍을 이용한 소셜커머스에서 소비자의 구매의도에 미치는 영향

Ruixue Song,임승희 한국유통경영학회 2020 유통경영학회지 Vol.23 No.5

Purpose: Live streaming service has been adopted by many sellers in social commerce. However, there has been limited attempts to identify consumers’ purchase behavior in social commerce via live streaming. In particular, research has not investigated the structural relationships between variables in terms of mediating and moderating effects. Therefore, the study examined the mediating effect of social presence and flow for the relationships among interactivity, relationship quality, and consumers’ purchase intention. The study also examined the moderating effect of social support for the relationships among social presence, flow, and consumers’ purchase intention.

모바일 결제시스템의 특성에 대한 인식도 연구

유서설(LIU RUIXUE),임관빈(Kwanbin Lim),김수정(Sujeong Kim),이선화(Sunhwa Lee),메리녕(Mary Nyunt),윤종수(Jongsoo Yoon) 한국컴퓨터정보학회 2022 한국컴퓨터정보학회 학술발표논문집 Vol.30 No.1

모바일 결제시스템의 특성이 지각된 가치에 미치는 영향 : 사용자 국적의 조절효과를 중심으로

유서설(Liu, Ruixue),윤종수(Yoon, Jongsoo) 한국상품학회 2021 商品學硏究 Vol.39 No.6

전 세계적으로 스마트폰과 태블릿PC 등의 빠른 사용자 수 증가와 함께 모바일 전자상거래의 이용률이 높아지면서 현금결제를 대신할 편리하고 안정적인 새로운 결제시스템에 대한 시장수요가 증대되고 있다. 모바일 결제시스템의 시장 확대 및 활성화에 힘입어 소비자들은 언제 어디서나 시간과 장소의 제약에서 벗어나 모바일 기기를 통해 다양한 제품을 손쉽게 구매할 수 있게 되었으며, 기업은 새로운 글로벌 시장에서 우위를 차지하기 위해 다양한 기능을 갖춘 모바일 결제시스템 도입을 위해 노력을 경주하고 있다. 이러한 배경하에, 모바일 결제시스템의 특성이 소비자들의 지각된 가치에 어떠한 영향을 미치는가를 파악할 필요성이 존재한다. 따라서, 본 연구는 한국과 중국의 사용자들을 대상으로 모바일 결제시스템의 특성이 지각된 가치에 어떠한 영향을 미치는지를 실증적으로 규명하고자 한다. 이와 함께, 본 연구는 사용자의 특성(국적)은 이러한 모바일 결제시스템의 특성과 지각된 가치 사이에 어떠한 역할을 하는가를 분석하는데 연구의 초점을 두고 있다. 본 연구의 주요 통계분석 결과를 요약하여 제시하면 다음과 같으며, 이를 통해 본 연구에서는 이론적 및 실무적 시사점과 함께 향후 연구방향을 다음과 같이 제시하였다. 첫째, 모바일 결제시스템의 특성 중에서 경제성을 제외한 효율성, 보안성, 신뢰성, 호환성은 지각된 가치에 정(+)의 영향을 미치는 것으로 파악되었다. 둘째, 모바일 결제시스템의 특성과 지각된 가치간의 관련성에 있어서 사용자의 특성(국적)은 부분적으로 조절 효과를 나타내고 있음을 알 수 있었다. Mobile payment system is becoming more common along with the use of mobile devices such as smart phone and tablet computer increases around the world. In other words, many customers have been able to search, compare and order various products and services what they want without restrictions on time and place in mobile Internet environment and even to make payments easily and conveniently. In order to flexibly respond to changes in these situations while continuing to maintain desirable relationships with customers, many companies are especially making various efforts to manage ‘perceived value’ which means how customers think about the mobile payment system. Considering this situation, it is necessary to investigate which properties of the mobile payment system have a significant effect on the perceived value of customers who use it. The study is to empirically identify which properties of mobile payment system affect the perceived value of those who use it and also is to analyze whether the relationship between the property of mobile payment system and the perceived value depends on the users’ nationality type. To achieve these research purposes, the study defined the property of mobile payment systems(security, efficiency, reliability, compatibility, economics) and perceived value(functional, emotional, social, economical) based on the literature review of mobile payment system. The study results show, from the statistical analyses using 400 survey questionnaires on Korean and Chinese mobile payment systems users, that most factors such as security, efficiency, reliability, compatibility except economics, among the property of mobile payment systems, have a statistically significant effect on the perceived value and that the users’ nationality has a partial moderating effect on the relationship between the property of mobile payment systems and the perceived value.

A Novel Procedure for Protection Setting in an HVDC System Based on Fault Quantities

Benfeng Gao,Ruixue Zhang,Xuewei Zhang 대한전기학회 2017 Journal of Electrical Engineering & Technology Vol.12 No.2

HVDC protection setting is difficult to be calculated analytically because of its strong nonlinearity. The currently used setting method is based on the empirical setting of previous projects and then verified by digital simulation. It entails a huge workload and low efficiency. To facilitate protection setting, this paper systematically summarizes the HVDC protection characteristics and then presents a classification of HVDC protections according to the protection principles. On the basis of the fault quantities, a novel setting procedure suitable for travelling wave protection, derivative and level protection, and differential protection is proposed. The proposed procedure is illustrated and verified in detail with the example of travelling wave protection. An HVDC protection setting system that has the functions of automatic protection setting and data management is developed utilizing the C# programming language.

Collaborative Innovation in Construction Project: A Social Network Perspective

Xiaolong Xue,Ruixue Zhang,Liang Wang,Hongqin Fan,Rebecca J. Yang,Jason Dai 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.2

Successful innovation requires effective cooperation and working relationships among different parties within construction projects. In order to promote construction innovation performance, it is important to shed light on the internal mechanism of innovation through investigating collaborative relationships from a network perspective. In this case, the formation of collaborative relationship can be viewed as a potential generator of innovation processes, and relationship network indicates information exchanges among organizations. This article investigates the collaborative relationship network in a commercial complex by using social network method and in-depth quantitative data analysis. Structural Equation Modeling (SEM) is usually used to analyze the impacts of collaborative relationship on innovation performance in construction projects. There are more and more stakeholders in construction projects, and organization relationship presents a significant network trend. Social network method is widely applied in innovative research. Combined with quantitative data, it is able to quantify and visual the interaction relations of innovation stakeholder. The analytical results will be more objective and reliable. Social network analysis can describe and analyzed collaborative relationship combining qualitative and quantitative method. The results illustrate the relatively dense collaborative relationship networks and highlight the roles that the key members played in the innovation process. The decomposition of collaborative relationship with network analysis contributes to a better understanding of innovation process in construction projects. In particular, key nodes which influence construction innovation through collaborative relationships are revealed and analyzed.

Performance Improvement Strategy for Parallel-operated Virtual Synchronous Generators in Microgrids

Hui Zhang,Ruixue Zhang,Kai Sun,Wei Feng 전력전자학회 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.2

The concept of virtual synchronous generators (VSGs) is a valuable means for improving the frequency stability of microgrids (MGs). However, a great virtual inertia in a VSG’s controller may cause power oscillation, thereby deteriorating system stability. In this study, a small-signal model of an MG with two paralleled VSGs is established, and a control strategy for maintaining a constant inertial time with an increasing active-frequency droop coefficient (m) is proposed on the basis of a root locus analysis. The power oscillation is suppressed by adjusting virtual synchronous reactance, damping coefficient, and load frequency coefficient under the same inertial time constant. In addition, the dynamic load distribution is sensitive to the controller parameters, especially under the parallel operation of VSGs with different capacities. Therefore, an active power increment method is introduced to improve the precision of active power sharing in dynamic response. Simulation and experimental is used to verify the theoretical analysis findings.