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Study on the Electron Injection of Newly Synthesized Organic Sensitizer in Dye-Sensitized Solar Cell

  • Gang, Tae-Yeon;Lee, Do-Gwon;Go, Min-Jae;Kim, Gyeong-Gon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.310-310
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    • 2010
  • Electronic and photovoltaic characteristics of two sensitizers (TA-BTD-CA and TA-BTD-St-CA), composed of a different $\pi$-conjugation in the linker group, have been investigated by theoretical and experimental methods. The electronic structure, transition dipole moment and oscillator strengths of two sensitizers have been scrutinized by using density functional theory (DFT) and time-dependent DFT (TD-DFT) method. The LUMO level and the oscillator strength of TA-BTD-St-CA was higher than that of TA-BTD-CA, which may facilitate the electron injection process as well as increase the absorption coefficient. The relative efficiencies of the electron injection from the excited sensitizer to nanocrystalline TiO2 and SnO2 films have also been investigated by nanosecond transient absorption spectroscopy. The relative electron injection efficiency of TA-BTD-St-CA exhibited similar injection efficiency for two different semiconductors. However, in the case of TA-BTD-CA sensitizer, electron injection into SnO2 was approximately three times larger than that into TiO2. This enhancement of electron injection of TA-BTD-CA for the SnO2 is due to the increment of the driving force caused by positive shift of conduction band of semiconductor, which was also confirmed from the investigation for the photovoltaic characteristics according to the electrolyte additive, such as LiI additive.

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A study on job satisfaction and the turnover intention of fire fighters (소방공무원들의 직무만족과 이직의도에 관한 연구)

  • Kim, Hong-Jo;Baek, Hong-Seok
    • The Korean Journal of Emergency Medical Services
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    • v.18 no.1
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    • pp.95-106
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    • 2014
  • Purpose : This study was attempted to check the correlation between job satisfaction and turnover intention and to provide the basic information to increase job satisfaction of fire fighters. Methods : A total of 369 questionnaires were distributed and 354 questionnaires were filled out and collected for analysis. Results : There was difference in turnover intention by general characteristics. According to position, group of Fire lieutenant or more is lower than that of Fire sergeant or less (F=3.61, p=.014). The group of rescue & emergency service and administration was significantly lower than other groups(F=4.84, p=.001). In pattern of duties, day service group was significantly lower than shift work group in .05 level(t=2.59, p=.022). Finally, in the correlation, the more job satisfaction increase, the more turnover intention decrease that represents inverse correlation between job satisfaction and turnover intention(r=-.523, p <.001). Namely, it represents the results that the higher job satisfaction is low turnover intention. Conclusion : More studies of fire officer in other cities are required to generalize the results. We have to develop program for job satisfaction for fire officer firstly, because program for job satisfaction used in this study was not developed for fire fighters.

Stimulatory Effects of Ginsenoside-Rg1 on p56lck Kinase and Cell Proliferation in Jurkat T Cells (Jurkat T 세포에서 Ginsenoside-Rg1이 p561ck Kinase 활성과 세포증식에 미치는 영향)

  • Hong, Hee-Youn;Na, Do-Seong;Kwon, Tae-Ik;Choi, Jung-Kap;Yoo, Gyurng-Soo
    • Journal of Ginseng Research
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    • v.19 no.2
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    • pp.117-121
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    • 1995
  • We studied the effects of ginsenoside-$Rg_1$ (G-$Rg_1$) extracted from Panax ginseng C.A. Meyer on $p56^{kk}$ kinase and cell proliferation in Jurkat T cells. $p56^{kk}$ was maximally activated within 5 min after the treatment of 16.7 $\mu\textrm{g}$/ml of G-$Rg_1$ increasing the activity by 1.2-2 times relative to untreated control, thereafter its activity was gradually decreased to the level of untreated control. The action of EGTA on the kinase was altered by the addition of G-$Rg_1$, accompanying the band shift of $p56^{kk}$ to $p60^{kk}$. In addition, G-$Rg_1$promoted cell proliferation in a concentration-dependent manner. These results suggest that G-$Rg_1$ may be involved in T cell receptor-CD3 (TCR) signaling via the activation of $p56^{kk}$ and the chance of cellular calcium concentration.

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Job Stress, Fatigue, Job Satisfaction and Commitment to Organization in Emergency Department Nurses (응급실 간호사의 직무 스트레스, 피로, 직무 만족 및 조직 몰입)

  • Oh, Myung Ok;Sung, Mi Hae;Kim, Yang Won
    • Journal of Korean Clinical Nursing Research
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    • v.17 no.2
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    • pp.215-227
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    • 2011
  • Purpose: This research was done to identify relationships among job stress, fatigue, job satisfaction, and commitment to organization in emergency department nurses. Methods: Research participants were 513 nurses who worked in the emergency department of 17 tertiary centers and 28 secondary hospitals. Data collection for this descriptive correlational study was done from May to July 2010 using self report questionnaires, and analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation coefficient with the SAS 9.2 program. Results: There were statistically significant differences in organizational commitment according to age, religion, total clinical experience, emergency department experience, current position, frequency of night shift, average sleep hours, wage level, numbers of beds in unit, and reason for working. A positive correlation was found between job stress and fatigue, and between job satisfaction and commitment to organization for the emergency department nurses and a negative correlation between job stress and Job satisfaction, and fatigue and Job satisfaction. Conclusion: Results of this research indicate that job stress in emergency department nurses was the principal variable affecting job satisfaction and commitment to organization along with fatigue. Appropriate stress management strategies based on identification of job stress for these nurses should lead to development of improved management of nursing manpower and a reduction in stress.

A Teacher Research on Integrating English Reading and Writing: The Use of Intermediate Texts in an EFL Class

  • Kim, Sun-Young
    • Cross-Cultural Studies
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    • v.20
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    • pp.67-111
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    • 2010
  • This paper examined the role of intermediate texts in the writing process in the context of an EFL composition class. From the tradition of teacher research, this study examined how the Korean college students in different proficiency groups created intermediate texts and used them while composing their own writing. The students produced various types of intermediate texts during the compositing process, which could serve as a basis of their writing. However, the patterns of using these intermediate texts differed widely across the proficiency groups. A writing cycle for the low proficiency group, or "surface reading-few intermediate texts-writing," indicates that less proficient students tended to engage in reading in separation of writing practices and thus produced few intermediate texts through their literacy practices. On the other hand, the students in the higher proficiency groups revealed the more integrated pattern (i.e., purpose reading/intermediate texts/writing), indicating that they often engaged in reading with specific writing purposes, practiced reading in connection to other writing practices, and elaborated written intermediate texts produced. This study argues that, to shift our student writers to a higher level category, we as teachers need to help them engage in reading and writing practices in the way they produce and use intermediate texts appropriate to their specific writing purposes.

Noise Reduction Algorithm For The Detection of Fine Ion Signals in Residual Gas Analyzer (잔류가스분석기의 질량 스펙트럼 검출 성능 향상을 위한 잡음제거 알고리즘)

  • Heo, Gyeongyong;Choi, Hun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.68 no.1
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    • pp.102-107
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    • 2019
  • This paper proposes a method to improve the mass spectral detection performance of the residual gas analyzer. By improving the mode estimation method for setting the threshold value and improving the additive noise elimination method, it is possible to detect mass spectrums having low peak values of the threshold level difficult to distinguish from noise. Ion signal blocks for each mass index with noise removed by the improved method are effective for eliminating invalid ion signals based on the linear and quadratic fittings. The mass spectrum can be obtained from the quadratic fitted curves for the reconstructed ion signal block using only the valid ion signals. In addition, the resolution of the mass spectrum can be improved by correcting the error caused by the shift of the spectral peak position. To verify the performance of the proposed method, computer simulations were performed using real ion signals obtained from the residual gas analysis system under development. The simulation results show that the proposed method is valid.

Health Belief Model-based Needs Assessment for Development of a Metabolic Syndrome Risk Reduction Program for Korean Male Blue-collar Workers in Small-sized Companies (건강신념모델을 기반한 소규모 산업장 생산직 남성근로자의 대사증후군 감소 프로그램 개발을 위한 요구사정)

  • Park, Yunhee;Kim, Dooree
    • Korean Journal of Occupational Health Nursing
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    • v.27 no.4
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    • pp.235-246
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    • 2018
  • Purpose: This study aimed to comprehend the real context of metabolic syndrome-related factors of Korean male blue-collar workers from small-sized companies based on the health belief model. Methods: A total of 37 workers from three companies were interviewed, and three series of focus group interviews were conducted. Data were analyzed using deductive content analysis. Results: Data were classified into four categories: knowledge, perceived susceptibility and severity, perceived barriers, and beliefs. Knowledge referred to low knowledge level; perceived susceptibility and severity referred to unawareness of susceptibility and severity; perceived barriers referred to shift work, overtime work, and a social context including having no choice but to drink; and beliefs referred to believing that health promotion behaviors do not relate to preventing metabolic syndrome, believing that one cannot prevent metabolic syndrome oneself, and believing that professional help is required. Conclusion: To prevent and reduce the risk of metabolic syndrome among Korean male blue-collar workers, interventions should focus on strategies to increase metabolic syndrome-related knowledge and perceptions, social support, and self-efficacy for practicing health behaviors. In addition, it is necessary to develop policies for establishing a healthy drinking culture in companies.

HTS high gradient magnetic separator prototype

  • Diev, D.N.;Lepehin, V.M.;Makarenko, M.N.;Polyakov, A.V.;Shcherbakov, V.I.;Shutova, D.I.;Surin, M.I.;Tagunov, E. Ya.
    • Progress in Superconductivity and Cryogenics
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    • v.20 no.4
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    • pp.1-5
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    • 2018
  • A high gradient magnetic (HGM) separator prototype with the $2^{nd}$ generation high temperature superconducting (2G HTS) magnetic system operated in sub-cooled nitrogen is presently under development at NRC "Kurchatov Institute" (Moscow, Russia). The main goal of the project is an attempt to shift away from the complicated liquid helium cryostats towards simple cryocooler-based nitrogen cryogenics as much more convenient for HGM separators industrial applications. Using of commercial HTS tapes allows to get a sufficient level of magnetic fields and extraction forces with low energy consumption. The expected operational parameters of the device are 1.2-1.5 T in the empty operational gap and up to 3 T on the ferromagnetic filters. In this paper we briefly describe the design of the HTS rotary separator prototype with the horizontally oriented rotor axis and propose different types of ferromagnetic filters intended for weakly magnetic ores enrichment.

The Egyptian Foreign Policy Orientations and Its Relations with Russia after June 30th Revolution

  • ELMAGHRABY, BASSEM
    • Korea and Global Affairs
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    • v.3 no.1
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    • pp.183-220
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    • 2019
  • Bearing in mind the strategic and pivotal importance of Egypt over the Arab, African, Middle Eastern, Islamic and even global level; this paper aimed to figure out how and why the Egyptian foreign policy has been changed over time; and whether the flourishing of Egyptian-Russian relations represent a shift from West to East; and show how the historical experiences affecting the relations between Egypt and Russia; moreover, explains why Russia supported June $30^{th}$ revolution while it opposed January $25^{th}$ revolution only two years earlier and other Arab Spring revolutions from one side; and why Egypt accepted to further develop its relations with Russia from the other side.

Influence of Allyl Isothiocyanate on the Soil Microbial Community Structure and Composition during Pepper Cultivation

  • Gao, Jingxia;Pei, Hongxia;Xie, Hua
    • Journal of Microbiology and Biotechnology
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    • v.31 no.7
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    • pp.978-989
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    • 2021
  • Allyl isothiocyanate (AITC), as a fumigant, plays an important role in soil control of nematodes, soil-borne pathogens, and weeds, but its effects on soil microorganisms are unclear. In this study, the effects of AITC on microbial diversity and community composition of Capsicum annuum L. soil were investigated through Illumina high-throughput sequencing. The results showed that microbial diversity and community structure were significantly influenced by AITC. AITC reduced the diversity of soil bacteria, stimulated the diversity of the soil fungal community, and significantly changed the structure of fungal community. AITC decreased the relative abundance of dominant bacteria Planctomycetes, Acinetobacter, Pseudodeganella, and RB41, but increased that of Lysobacter, Sphingomonas, Pseudomonas, Luteimonas, Pseudoxanthomonas, and Bacillus at the genera level, while for fungi, Trichoderma, Neurospora, and Lasiodiplodia decreased significantly and Aspergillus, Cladosporium, Fusarium, Penicillium, and Saccharomyces were higher than the control. The correlation analysis suggested cellulase had a significant correlation with fungal operational taxonomic units and there was a significant correlation between cellulase and fungal diversity, while catalase, cellulose, sucrase, and urease were the major contributors in the shift of the community structure. Our results will provide useful information for the use of AITC in the assessment of environmental and ecological security.