A New Parameter Reduction Method Based on Soft Set Theory

Qiwen Zhang,Xueqin Wang 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.5

In order to solve the problems of large calculation and low efficiency of parameter reduction, a new parameter reduction method based on soft set theory is proposed. According to the importance degrees of parameters, this new parameter reduction method simplifies the reduction complexity brought by the equivalent classes in discernibility matrix, so that it not only improves the parameter reduction efficiency and quality, but also reduces the reduction complexity. Finally, comparing with other reduction methods, this new parameter reduction method based on soft set theory not only possesses feasibility and high efficiency, but also can make the reduction result more accurate.

Post Fire Effects on Structural and Hydrological Properties of Forest Soils

( Qiwen Li ),( Sangjun Im ),( Taehyun Kim ),( Jeman Lee ) 대한지질공학회 2019 대한지질공학회 학술발표회논문집 Vol.2019 No.2

A fire is one of the most dangerous events that lead to irreversible consequences on forest environment. All organic matters over and near the ground surface can burn in a fire. Combustion of forest fuels causes significant changes in soil structure and property. Fire-induced repellent layer plays an important role in controlling runoff and erosion processes after a fire. Therefore, an intensive survey on soil structure and hydrologic charactristics is needed to quantitatively examine the effects of fire on water movement and soil erosion. In this study, spatial and temporal patterns of soil properties were observed on forestlands in Gangwon province, affected by the 2019.04.04 fire. Soil texture, degrees of ash layer and soil water repellency were measured according to fire severity and fire type. Water Drop Penetration Time (WDPT) was implemented to measure the extent of soil water repellency for burnt soils. Through the field investigation, the results showed that soil properties changed with high heat, but the influences reached only a few centimeter near the soil surface. The extent and pattern of soil hydrophobicity have close relations to fuel types and fire intensities. Soil water repellency decreased with time, mainly due to raindrop impacts and soil sheet erosion. Acknowledgment This study was carried out with the support of ‘R&D Program for Forest Science Technology (Project No. 2017061B10-1919-AB01)’ provided by Korea Forest Service (Korea Forestry Promotion Institute)

Micellization and aggregation properties of sodium perfluoropolyether carboxylate in aqueous solution

Qiwen Yin,Wanxu Wang,Wei Xue,Yanyun Bai,Xiaoyuan Ma,Zhiping Du,Guoyong Wang 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.42 No.-

Sodium perfluoropolyether carboxylate (PFPE-Na) was synthesized via hydrolyzing the correspondinghexafluoropropylene oxide oligomer (PFPF). The structure of PFPE-Na was characterized by FT-IR and 19FNMR. The micellization and aggregation properties of PFPE-Na surfactant in aqueous solution werestudied systematically using equilibrium surface tension, electrical conductivity, dynamic surfacetension, steady-statefluorescence, transmission electron microscopy (TEM) and contact anglemethodologies. The results of equilibrium surface tension at 25 C showed that the critical micelleconcentration (CMC) and the surface tension at CMC (gCMC) of PFPE-Na aqueous solution are lower thansodium perfluorooctanoate [NaPFO, C7F15COONa], which revealing that as a kind of environment-friendly surfactant, PFPE-Na is a perfect substitute of NaPFO. Electrical conductivity measurementsimplied that the micellization of PFPE-Na in aqueous solution was an exothermic and entropy-drivenprocess in the range of temperature investigated. Steady-statefluorescence and transmission electronmicroscopy (TEM) may indicate that PFPE-Na self-assemble in aqueous solution to form larger sphericalaggregates with the increase of concentration. In addition, dynamic surface tension measurements ofPFPE-Na solution showed an extremely efficient adsorption at concentrations above CMC while thedetermination of contact angle of PFPE-Na showed the wetting ability was general.

연구논문(硏究論文) : 활엽수 낙엽의 수분저류 특성에 대한 실험적 분석

( Qiwen Li ),최형태 ( Hyungtae Choi ),이은재 ( Eun Jai Lee ),임상준 ( Sangjun Im ) 한국환경복원기술학회(구 한국환경복원녹화기술학회) 2016 한국환경복원기술학회지 Vol.19 No.2

This study purposed to examine the water retention capacity of floor litter in deciduous forests. Water holding capacity(WHC) and interception storage capacity of Alnus hirsuta Turcz. ex Rupr., Quercus acutissima, Quercus mongolica litters were experimentally estimated. Physical characteristics of litters were also obtained to understand the relationships between water-retention capacity and litter characteristics. Experiments showed that WHC increases with specific volume of litter, varying 244.4% to 416.8% of its dry mass. Interception storage have estimated with rainfall simulation experiments. Maximum interception storage (Cmax) and minimum interception storage (Cmin) of litters were 220% and 138% of dry mass in Alnus hirsuta Turcz. ex Rupr., 218% and 137% in Quercus acutissima, and 240% and 156% in Quercus mongolica. Both Cmax and Cmin increased linearly with litter mass, and the values of Cmin in broadleaf litters have also linear relation to leaf area.

A Ranking Method Based on Extended Possibility Degree Dominance Relation

Qiwen Zhang,Xueqin Wang 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.6

Dominance relation is an important method in incomplete interval-valued information systems. In order to solve the problem that too many attributes maybe result in the ranking failure in the incomplete interval-valued information systems, the concepts of extended possibility degree, extended possibility degree dominance relation and average comprehensive dominance degree are defined. Based on them, a ranking method based on extended possibility degree dominance relation is proposed. Finally, comparing with other ranking methods, this new ranking method based on extended possibility degree dominance relation not only has stronger differentiation degree, but also can make ranking results more objective and reasonable.

Genetic diversity and phylogenetic analysis of porcine reproductive and respiratory syndrome virus in southern China from 2007 to 2014

Qiwen Wu,Zhili Li,Guanqun Zhang,Jianqiang Niu,Xiduo Zeng,Baoli Sun,Jingyun Ma 대한수의학회 2017 Journal of Veterinary Science Vol.18 No.3

Porcine reproductive and respiratory syndrome virus (PRRSV) has a high degree of genetic variation. In this study, we characterized the genetic variation and evolutionary relationships among circulating PRRSV strains in southern China. We analyzed 29 NSP2 strains and 150 ORF5 strains from clinical samples collected in southern China during 2007–2014. The alignment results showed that the nucleotide identity similarities of the two genes among these strains were 80.5%–99.7% and 80.9%–100%, respectively. Phylogenetic analysis based on the NSP2 gene showed that highly pathogenic (HP)-PRRSV was still the dominant virus in southern China from 2013 to 2014. Compared with reference strains CH-1a and VR-2332, the field strain 131101-GD-SHC, which shared high homology with JXA1-P170, had a novel 12 amino acid deletion at position 499-510. Phylogenetic analysis based on the ORF5 gene showed that HP-PRRSV, VR2332-like strains, and QYYZ-like strains were simultaneously circulating in southern China from 2007 to 2014, suggesting that, in recent years, the type 2 PRRSV was more diverse in southern China. In conclusion, mutations in the decoy epitope and primary neutralizing epitope could be markers of viral evolution and used to study evolutionary relationships among PRRSV strains in China.

유아교사의 수학적 상호작용에 대한 수학지원지식의 영향: 교수창의성의 조절효과를 중심으로

Bo Qiwen,김지현 학습자중심교과교육학회 2024 학습자중심교과교육연구 Vol.24 No.4

목적 본 연구에서는 유아교사의 놀이교수효능감 및 수학지원지식이 수학적 상호작용에 미치는 영향력에 대한 교수창의성의 조절효과가 유의한지를 검증하였다. 방법 이를 위하여 수도권 소재 어린이집과 유치원에 재직하고 있는 유아반 담임교사 300명을 선정하였다. 측정도구는 김지현과권기남(2022)의 유아교사용 수학적 상호작용 척도, 홍희주와 정정희(2012)의 수학교과교육학지식 척도, 백영숙과 김희태(2008) 가 타당화한 교수창의성 척도를 사용하였다. 자료분석은 SPSS 22.0 프로그램을 사용하여 빈도, 백분율, 평균, 신뢰도분석, 편상관분석, 조절효과 분석을 위한 중다회귀분석, 조절효과 분석을 실시하였다. 이 때, 재직과정연수현황, 경력, 학습지사용횟수, 담임교사수를 통제변인으로 투입한 후 위계적 중다회귀분석을 실시하였다. 결과 유아교사의 수학적 상호작용에 대한 수학지원지식의 영향력은 교수창의성에 의해 조절되는데, 수학지원지식이 높으면서 교수창의성도 높은 집단이 가장 수학적 상호작용을 빈번하게 일상에서 하였다. 결론 본 연구는 유아교사의 교수창의성이 수학지원지식의 수학적 상호작용에 대한 영향력을 조절하는 역할을 하여 수학적 상호작용에 영향을 미치는 변인들에 있어 교수창의성의 역할이 중요하다는 점을 발견하였다. 따라서 교수창의성 향상을 위한 교육적, 제도적 지원이 우선적으로 필요하다는 점을 밝혔다. Objectives In this study, it was verified whether the moderating effect of teaching creativity on the effect of early childhood teachers' play teaching efficacy and mathematics pedagogical content knowledge on mathematical interaction was significant. Methods For this purpose, 300 nursery class teachers working at daycare centers and kindergartens in the metropolitan area were selected. As a measuring tool for the mathematical interaction of early childhood teachers, Kim and Kwon (2022)'s tools and early childhood teachers' mathematics subject pedagogical knowledge tool developed by Hong and Jeong (2012) were used to find out mathematics pedagogical content knowledge. In order to measure teaching creativity, the ‘teacher's creative teaching-learning test tool’ developed by Cropley (2004) was modified and adapted by Baek and Kim (2008) and validated and verified. For data analysis, frequency, percentage, average, reliability analysis, partial correlation analysis, multiple regression analysis for moderating effect analysis, and moderating effect analysis were conducted using the SPSS 22.0 program. At this time, a hierarchical multiple regression analysis was conducted after injecting the status of tenure and training, career, number of times of use of study materials, and the number of homeroom teachers as control variables. Results The effect of mathematics pedagogical content knowledge on the mathematical interaction of early childhood teachers was regulated by teaching creativity. Conclusions This study found that the early childhood teacher's teaching creativity plays a role in regulating the effect of mathematics pedagogical content knowledge on mathematical interaction, and thus the role of teaching creativity is important in the variables that affect mathematical interaction. Therefore, it was revealed that educational and institutional support for improving teaching creativity is needed first.

Correlation Analysis of Pollutant Factors Influencing the Sulfite/UV-L Advanced Reduction Process

Mei Qiwen,Ki Hoon Kim,한인섭 대한토목학회 2018 KSCE Journal of Civil Engineering Vol.22 No.2

In this study, factors that influenced the process of trichloroethylene (TCE) degradation using the sulfite/UV-L Advanced Reduction Process (ARP) were analyzed, as well as the interrelation of these factors, the correlation between factors, and the trichloroethylene (TCE) degradation efficiency. Four factors were evaluated: pH, reductive reagent (sulfite) concentration, UV254 intensity, and trichloroethylene (TCE) concentration. The efficiency of trichloroethylene (TCE) degradation by the sulfite/UV-L Advanced Reduction Process (ARP) increased as the initial pH increased. Considering economy, pH 10 was decided as the optimum condition. The trichloroethylene (TCE) degradation efficiency by sulfite/UV-L Advanced Reduction Process (ARP) also increased with increasing sulfite concentration. According to the experimental results, the optimum sulfite concentration to treat 10 mM of the trichloroethylene (TCE) was 10 mg/L. The degradation efficiency of the trichloroethylene (TCE) also increased as the intensity of UV254 radiation was increased. Higher initial concentrations of trichloroethylene (TCE) resulted in decreased degradation efficiency. All the factors also been analyzed using multiple regression carried out by the program SPSS (ver. 22). The pH seemed to have a high correlation with looking pearson coefficient. It is most important to consider the influence of pH when using sulfite/UVL Advanced Reduction Process (ARP). The initial concentration of trichloroethylene (TCE) seemed to have the most relevance by looking pearson coefficient, followed by pH and UV254. The regression model seemed to be appropriate, having a value (0.000), which was much lower than the significance level (0.05), and the correlation coefficient (R2) of 0.816 describes the power elimination rate of trichloroethylene (TCE).

한국과 중국 유아교사의 구성주의신념 및 수학적 태도와 수학지도지식의 관계

박기문(Bo, Qiwen),김지현(Kim, Jihyun) 한국인간발달학회 2020 人間發達硏究 Vol.27 No.3

본 연구에서는 한국과 중국 유아교사의 수학지도지식에 대한 구성주의신념과 수학적 태도의 상대적 영향력은 어떠한지를 검증하였다. 이를 위해 한국 수도권에 소재한 어린이집과 유치원에 재직하고 있는 유아교사 150명과 중국 산동성에 소재한 유치원에 재직하고 있는 유아교사 150명, 총 300명을 대상으로 질문지를 통한 연구를 실시하였다. 자료분석은 SPSS 22.0프로그램을 사용하였고 t-검증, 편상관분석, 단계적 중다회귀분석을 실시하였다. 본 연구의 결과는 다음과 같다. 첫째, 한국과 중국 유아교사의 구성주의신념에 대하여 유의한 차이가 없고, 한국 유아교사의 수학적 태도와 수학지도지식이 중국 유아교사에 비해 낮았다. 둘째, 한국과 중국 유아교사의 수학지도지식에 대해 대체적으로 유아교사의 구성주의신념과 수학적 태도 순으로 영향력을 미쳤다. 그러나 한국 유아교사의 수학지도지식에는 수학을 얼마나 즐거워하느냐가 구성주의신념 다음으로 영향력을 미치는 반면, 중국 유아교사의 경우에는 수학을 하고자 하는 동기가 구성주의신념 다음으로 영향력을 미쳤다. 본 연구의 결과는 한국과 중국 유아교사의 수학지도지식 향성을 위한 구성주의신념, 수학적 태도를 포함한 교사교육 프로그램의 개발을 위한 기초자료로 활용될 수 있다. We studied how the relative influence of the constructive beliefs and mathematical attitudes of teachers in the two countries affects MPCK. For this purpose, a questionnaire was conducted with a total of 300 teachers in the education centers and kindergartens in a metropolitan area in Korean and 150 teachers at kindergartens in Shandong Province, China. The data analysis was conducted with SPSS 22.0 program by t-tests, partial correlation assessments, and a stepwise multiple regression analysis. The results of this study are as follows. First, there were no significant differences in the constructive beliefs between Korean and Chinese teachers, and the mathematical attitude and the MPCK, of Korean teachers were lower than those of Chinese teachers. Second, the MOCK of Korean and Chinese teachers was generally influenced by the order of their constructive beliefs and mathematical attitudes. However, for the Korean teachers, the degree of their interest in mathematics was second only to their constructive beliefs, whereas, for the Chinese teachers, their motivation to engage in math is second to their constructive beliefs. These results can serve as basic data for the development of teacher education programs that take into consideration, constructive beliefs and mathematical attitudes for fostering MPCK in Korean and Chinese teachers.

Improvement of biocompatibility of PLGA polymeric scaffold via ceramic hybridization

박이안,이우걸,박선호,김현지,정치원,( Zheng Qiwen ),( Zheng Qiwen ) 한국공업화학회 2022 한국공업화학회 연구논문 초록집 Vol.2022 No.-