Fabrication and Characterization of Dodecyl-derivatized Silicon Nanowires for Preventing Aggregation

Shin, Donghee,Sohn, Honglae Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.11

Single-crystalline silicon nanowires (SiNWs) were fabricated by using an electroless metal-assisted etching of bulk silicon wafers with silver nanoparticles obtained by wet electroless deposition. The etching of SiNWs is based on sequential treatment in aqueous solutions of silver nitrate followed by hydrofluoric acid and hydrogen peroxide. SEM observation shows that well-aligned nanowire arrays perpendicular to the surface of the Si substrate were produced. Free-standing SiNWs were then obtained using ultrasono-method in toluene. Alkyl-derivatized SiNWs were prepared to prevent the aggregation of SiNWs and obtained from the reaction of SiNWs and dodecene via hydrosilylation. Optical characterizations of SiNWs were achieved by FT-IR spectroscopy and indicated that the surface of SiNWs is terminated with hydrogen for fresh SiNWs and with dodecyl group for dodecyl-derivatized SiNWs, respectively. The main structures of dodecyl-derivatized SiNWs are wires and rods and their thicknesses of rods and wire are typically 150-250 and 10-20 nm, respectively. The morphology and chemical state of dodecyl-derivatized SiNWs are characterized by scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy.

Factors of Korean Students' Achievement in Scientific Literacy

Shin, Donghee,Ro, Kooghyang 한국과학교육학회 2001 한국과학교육학회지 Vol.21 No.5

Korean students ranked the 3rd out of 32 participating countries in the first cycle of PISA(Programme for International Student Assessment) science field, which assessed 15-years-old students' scientific literacy. PISA developed several variables such as parents' socio-economic status, parents' educational attainment, family wealth, and cultural possession, to investigate the effects of background variables on scientific literacy. On the other hand, motivation and engagement in science study were not given much attention, partly because science was the minor area in the first cycle of PISA. Therefore, PISA Korea developed a series of variables to collect data on students' learning motives and out-of-school activities in science as a national option. The results are as followings. First, Korea was found to be one of the PISA participating countries with the scientific literacy achievement least influenced by parents' socio-economic status, family wealth, and parents' cultural possession. Second, the degree of achievement in scientific literacy according to parents' educational attainment was in a positive correlation, similar to the overall tendency of PISA. Third, the most crucial learning motive for Korean students was their desire to develop scientific thinking abilities or obtain science knowledge. On the other hand, choosing jobs in the field of science or parental expectation was the least important learning motive. In particular, the motive for scientific learning was found to have a positive relationship with the degree of scientific literacy achievement. Therefore, the higher the students achievement, the stronger the motive for scientific learning in order to develop their ability to think scientifically or acquire science knowledge. Fourth, Korean students were shown to participate very little in out-of-school scientific activities other than watching TV programs related to science. Whatever the activities may be, the more actively involved students are in out-of-school scientific activities, the higher their scientific literacy achievement. Fifth, Korean girls were rather passive compared to boys in all areas, including science learning motive and out-of-school scientific activities. The gender difference was especially more pronounced in out-of-school scientific activities with wider gaps in such activities as reading scientific books or articles and visiting science-related web sites.

Risk factors for lesions of the knee menisci among workers in South Korea’s national parks

Donghee Shin,Kanwoo Youn,Eunja Lee,Myeongjun Lee,Hweemin Chung,Deokweon Kim 대한직업환경의학회 2016 대한직업환경의학회지 Vol.28 No.-

Background: This study was designed to investigate the prevalence of the menisci lesions in national park workers and work factors affecting this prevalence. Methods: The study subjects were 698 workers who worked in 20 Korean national parks in 2014. An orthopedist visited each national park and performed physical examinations. Knee MRI was performed if the McMurray test or Apley test was positive and there was a complaint of pain in knee area. An orthopedist and a radiologist respectively read these images of the menisci using a grading system based on the MRI signals. To calculate the cumulative intensity of trekking of the workers, the mean trail distance, the difficulty of the trail, the tenure at each national parks, and the number of treks per month for each worker from the start of work until the present were investigated. Chi-square tests was performed to see if there were differences in the menisci lesions grade according to the variables. The variables used in the Chi-square test were evaluated using simple logistic regression analysis to get crude odds ratios, and adjusted odds ratios and 95 % confidence intervals were calculated using multivariate logistic regression analysis after establishing three different models according to the adjusted variables. Results: According to the MRI signal grades of menisci, 29 % were grade 0, 11.3 % were grade 1, 46.0 % were grade 2, and 13.7 % were grade 3. The differences in the MRI signal grades of menisci according to age and the intensity of trekking as calculated by the three different methods were statistically significant. Multiple logistic regression analysis was performed for three models. In model 1, there was no statistically significant factor affecting the menisci lesions. In model 2, among the factors affecting the menisci lesions, the OR of a high cumulative intensity of trekking was 4.08 (95 % CI 1.00–16.61), and in model 3, the OR of a high cumulative intensity of trekking was 5.84 (95 % CI 1.09–31.26). Conclusion: The factor that most affected the menisci lesions among the workers in Korean national park was a high cumulative intensity of trekking.

The Effect of Frequent Testing in Student Achievement and Student Perceptions of Frequent Testing

Donghee Shin(신동희) 학습자중심교과교육학회 2018 학습자중심교과교육연구 Vol.18 No.19

본 연구의 목적은 빈번한 시험이 학생들의 기말고사 성취도에 미치는 영향과 시험 빈도에 대한 학생들의 인식이 어떠한지를 조사하고자 함이다. 연구를 위한 자료는 47명의 한국 대학생을 대상으로, 2018년 봄 학기에 그들의 영어 듣기와 읽기 수업에서 수집했다. 23명의 실험 집단에게는 8번의 퀴즈가 주어졌고, 24명의 비교 집단에게는 2번의 퀴즈가 주어졌다. 두 집단 모두 퀴즈 외에 동일한 중간고사와 기말고사를 치렀고, 시험 빈도 외에는 가능한 똑같은 강 의 내용을 유지했고 똑같은 과제를 주었다. 중간고사, 기말고사, 사전테스트와 사후테스트의 결과는 빈번한 시험이 학생들의 기말고사 점수에 어떠한 영향을 주는 지 알아보기 위해 사용되었다. 연구 결과에 따르면, 두 집단의 기말고사 점수의 p 값은 .993으로, 통계적으로 유의미하지 않았다. 또한 설문조사와 인터뷰를 통해 빈번한 시험에 대한 학생들의 인식을 조사한 결과, 학생들은 빈번한 시험을 중간고사와 기말고사를 대비하는 데 있어 공부를 게을리 하지 않을 수 있고 학습내용을 기억하고, 추가적인 공부를 더 하는 데에 도움이 되는 것으로 인식하였다. The purpose of this study is to examine the effect of frequent testing in student achievement on final exams and students’ perceptions of frequent testing. For the study, the data were collected from 47 Korean university students taking an English reading and listening course in the spring of 2018. Students in a treatment group (n=23) were given 8 quizzes; students in a comparison group (n=24) were given 2 quizzes. Both groups had the same midterm and final exams in addition to the quizzes. Results of the midterm exam, final exam, pretest, and posttest in the study were used to explore the effect of frequent testing on students’ scores on final exams. The results of the study indicated that the p-value of the two groups’ final exam scores was .993 demonstrating that the two groups’ final test results were not statistically different. Furthermore, this study investigated students’ perceptions of frequent testing through the use of survey and interview. The survey and interview results revealed that students viewed frequent testing as beneficial in preparing for midterm and final exams, in not procrastinating on studying, in improving retention of the learned course material, and in studying more.

Interaction, engagement, and perceived interactivity in single-handed interaction

Shin, Donghee,Choi, Myunggoon,Hyun Kim, Jang,Lee, Jae-gil Emerald (MCB UP ) 2016 INTERNET RESEARCH Vol.26 No.5

An Assessment of Korean Students’ Environmental Literacy

Shin Donghee,Chu Hyeeun,Lee Eunah,Ko Heeryung,Lee Moonam,Kang Kyunghee,Min Byungmee,Park Junehee The Korean Earth Science Society 2005 한국지구과학회지 Vol.26 No.4

This study was initiated to understand what students know, how they feel, and how they act in the perspectives of environmental literacy. This study takes it a very serious problem that there has been no data about Korean students’status of environmental literacy so far. Based on the correct diagnosis of Korean students’ environmental literacy, environmental education in Korea, including national curriculum, teaching materials and strategy, would take the right way. This study accepts Simmon (1995)’s framework of environmental literacy, consisting of 5 areas, environmental knowledge, skills, affect, and behavior, which is consistent with general goals of environmental education. This study analyzed the relationship between areas in environmental literacy and factors contributing to improving students’ environmental literacy. This study also checked which factors, including age, gender, parents’ schooling, environmental education in schools, and students’ science-related attributes, contributed to improving students’ environmental literacy. The results of this study will help science educators keep in mind how important it is to teach science from the perspectives of environmental literacy.

Synthesis and Characterization of Microwave-Exfoliated Graphene Oxide-Wrapped Silicon Nanowire via Hydrosilylation.

Shin, Donghee,Cho, Bomin,Ahn, Jihoon,Kim, Sungsoo,Ko, Young Chun,Sohn, Honglae American Scientific Publishers 2015 Journal of nanoscience and nanotechnology Vol.15 No.2

<P>Single-crystalline silicon nanowires (SiNWs) were fabricated by using an electroless metal-assisted etching of bulk silicon wafers with silver nanoparticles obtained by wet electroless deposition. The etching of SiNWs is based on sequential treatment in aqueous solutions of silver nitrate followed by hydrofluoric acid and hydrogen peroxide. Free-standing SiNWs were then obtained using ultra-sono method in toluene. Graphene oxide was prepared using the modified Hummers' process. Activated microwave-exfoliated graphite oxide (MEGO) was prepared and used for composition of silicon nanowires and graphene oxide via hydrosilylation. The silicon nanowire-graphene composite materials were characterized using XPS and FE-SEM.</P>

The Reliability of Self- and Peer Assessment and Students’ Perceptions toward Peer and Teacher Assessment

Donghee Shin 한국영어교과교육학회 2017 영어교과교육 Vol.16 No.4

The purpose of this study is to investigate the reliability of self- and peer assessment and students’ perceptions of peer and teacher assessment as students’ perspectives influence their learning. The data for this study were collected from 51 undergraduates taking an English oral presentation class in a university. Results were compared with the scores given by self, peers, and the instructor. The analysis of the data revealed that a greater correlation was found between peer and teacher assessments than between self- and teacher assessments. Thus, the study concluded that peer assessment is relatively more applicable than self-assessment for marking the students’ oral presentations; accordingly, including self-assessment marks into students’ presentation grades should be cautiously examined. In addition, this study examined students’ perceptions of peer and teacher assessment using a survey. The results indicated that students viewed both of them as beneficial and valuable for enhancing their oral presentation skills.

A Study on Non-English Major Students’ English Learning Anxiety in General English Conversation Class

신동희(Donghee Shin),문지순(Grace Ge-Soon Moon) 한국문화융합학회 2020 문화와 융합 Vol.42 No.9

The purpose of this study was to investigate the factors causing language anxiety by non-English major university students taking general English conversation class in a women’s university in Seoul. It also aimed to examine if their level of anxiety is significantly varied in terms of their age, fields of majors, and length of studying English. For the study, the subjects were 514 first-year students in Korean EFL (English as a Foreign Language) classrooms during a 15-week semester in the fall of 2019. The participants responded to a 23-item modified survey based on Horwitz’s Foreign Language Classroom Anxiety Scale (FLCAS). In order to find out 1) what factors make learners anxious while learning EFL and 2) how their English learning anxiety varies by age, different fields of majors, and length of studying English, their responses to the questionnaire were analyzed by using SPSS 26. The findings revealed that most anxiety-provoking factors among students were their fear of (1) making grammatical mistakes, (2) having oral tests, and (3) speaking without preparation in class. Furthermore, a ANOVA was used to analyze the responses. The study found a significant difference in terms of length of studying English (F = 5.559 and p-value was .000 on the ANOVA test). In respect to age and different fields of majors, the ANOVA test disclosed that there was no significant difference. 본 연구의 목적은 서울의 한 여자 대학교에서 영어회화 수업을 수강하는 비영어전공 대학생들의 언어 불안을 유발하는 요인들이 무엇인지 조사하고 그들의 불안 수준에 나이, 계열, 그리고 영어 학습기간에 따라 유의미한 차이가 있는지 검토하고자 함이다. 연구 대상은 2019년 가을 학기에 교양영어 수업을 15주 간 수강한 514명의 1학년 한국 대학생들이다. 이들은 Horwitz의 Foreign Language Classroom Anxiety Scale (FLCAS)(외국어 교실 불안 척도)를 바탕으로 23문항으로 수정된 설문에 응답하였다. 1) English as a Foreign Language (EFL) 학습 중 불안을 유발하는 요인이 무엇인지, 2) 나이, 계열, 영어 학습기간에 따라 학습 불안이 어떻게 달라지는지를 알아보기 위해 SPSS 26을 이용하여 설문에 대한 응답을 분석하였다. 그 결과, 학생들의 불안 유발 요인은 대부분 (1) 문법적 실수를 하는 것, (2) 구술시험을 치르는 것, 그리고 (3) 준비 없이 수업 시간에 말하기였다. 응답을 분석하기 위해 ANOVA test를 사용한 결과 영어 학습기간에 있어서 유의미한 차이를 보였다 (F=5.559, p-value = .000). 한편, 나이와 계열에 따른 차이를 분석한 결과, 유의한 차이가 없는 것으로 나타났다.

중등 환경 교과서와 10학년 과학 교과서의 공통 내용 분석

신동희(Donghee Shin),손연아(Yeona Son),박준희(Junehee Park) 한국환경교육학회 2008 環境 敎育 Vol.21 No.3

This study aims to analyze the science content in secondary school environmental education(EE) textbooks and the environment-related content in secondary school science textbooks. Firstly, a total of 73 EE and science textbooks for secondary students were reviewed, which three kinds of textbooks, secondary school EE textbooks and the 10th grade Science textbooks, were finally selected for analysis. Three researchers separately analyzed the textbooks using NAAEE framework(1996) for the development of EE materials. In condition that there was a disagreement in their opinion, they had discussed until they came to an agreement. The results showed that secondary school EE textbooks contained more and deeper science concepts than the 10th grade Science textbooks, which were evaluated better in all perspectives of the analysis framework. The 10th grade Science textbooks had more various teaching and learning activities than EE textbooks. It it expected that the new EE textbook developers should consider the ultimate goal of EE which focused the affective perspectives rather than the cognitive perspectives.