본 연구의 목적은 가상현실 체육실 수업의 실재 경험이 즐거움과 몰입을 경험할 때 스포츠 활동 참여의도에 어떤 영향을 미치는지 알아보는 것이다. 조사는 초등학교 고학년을 대상으로 총 300명을 60부 씩 표본추출하여 설문지 중 응답이 불성실한 24부를 제외하고 총 276부의 자료를 연구에 사용하였다. 본 연구에서 사용한 데이터 처리는 SPSS ver. 24.0 및 AMOS 버전. 24.0 통계프로그램을 이용하여 확증요인 분석, 빈도분석, Cronbach's α 계수계산, 상관분석, 구조방정식모형분석을 실시하였다. 이러한 과정을 통 해 다음과 같은 결과를 도출하였다. 첫째, 가상현실 체육실 수업의 실재 체험은 즐거움에 정(+)의 영향을 미쳤다. 둘째, 가상현실 체육실 수업에서 즐거움과 몰입의 관계는 정(+)의 영향을 미쳤다. 셋째, 가상현실 체육실 수업의 즐거움은 체육활동 참여의도에 정(+)의 영향을 미쳤다. 넷째, 가상현실 체육실에 참가한 학 생들의 수업몰입도는 향후 체육활동 참여의도에 정(+)의 영향을 미쳤다.

저층 침적 위험·유해물질(Hazardous and Noxious Substances)은 해저에 침적되는 위험·유해물질로 직접 및 광학 탐지 기법의 적용 이 어렵기 때문에 수중에서 효과적인 음향 탐지 기법 적용이 요구된다. 본 연구에서는 저층 침적 위험·유해물질인 클로로폼(Chloroform)을 이용한 후방산란신호 측정 실험을 통해 저층 침적 위험·유해물질 음향 탐지 가능성을 확인하였다. 제작된 아크릴 수조 내에 지점토를 이 용하여 웅덩이를 만든 후 Pan&Tilt를 이용하여 수평입사각을 90°에서 50°까지 0.5° 간격으로 변화시켜가며 클로로폼 유무에 따른 후방산란 신호 측정이 수행되었다. 송수신기를 단상태로 주파수 200 kHz, 신호길이 25 인 정현파 신호를 이용하여 송수신하였으며, 클로로폼 유 무에 따른 후방산란신호를 측정하였다. 클로로폼이 침적된 경우 수평입사각 약 80°이하에서 물과 클로로폼 경계면에서의 후방산란신호 수신준위가 작아지는 것이 확인되었다. 물과 클로로폼 경계면에서의 후방산란신호 측정된 결과를 통해 저층 침적 위험·유해물질 음향 탐 지 가능성을 확인하였다.

Purpose: Since the COVID-19 pandemic, virtual simulation practice has been increasingly activated as an alternative to clinical practice in nursing colleges. This study aimed to provide basic data by confirming changes in self-efficacy and nursing knowledge in the virtual simulations of nursing students, and identifying virtual presence, virtual patient learning system evaluation (VPLSE), and practical satisfaction. Methods: This was a single-group pre-post quasi-experimental study. The subjects were 28 third-grade nursing students. Results: Self-efficacy and nursing knowledge increased significantly (p<.001). Virtual presence had a significant positive correlation with VPLSE) (p=.002) and practice satisfaction (p=.011). There was also a significant positive correlation between virtual simulation learning evaluation and practice satisfaction (p<.001). Conclusion: Based on these results, virtual simulation practice can be used with clinical practice as an educational method to improve nursing students' self-efficacy and nursing knowledge in nursing education. Virtual presence was confirmed as a significant variable to improve practice satisfaction and VPLSE. It is necessary to develop a virtual simulation program that can improve virtual presence through collaboration with virtual reality technology experts.

In order to provide basic data for preparing management standards and to verify the safety of the Chinese oak mushroom-derived moisturizing medium—which is synthesized and imported in large quantities—the presence of 321 residual pesticides, 7 heavy metals, and 3 radioactive materials was analyzed in the moisturizer samples. Examination of residual pesticides in seven moisturizing medium samples prepared using the Chinese oak mushroom and three domestic sawdust samples used for mushroom culture revealed the presence of cypermethrin and iprodione in three moisturizer samples, but the contents of these pesticides were below the standard limits. Zn was detected in ten samples, Cu was detected in nine samples, and Ni was detected in four samples, but their contents were below the standard limits. Pb, Cd, Cr, and Hg were not detected in any sample. No radioactive materials were detected in the samples. In addition, fruiting bodies of the oak mushroom were observed in each medium. Examination did not reveal the presence of any residual pesticides or harmful compounds. In this study, the use of the moisturizing medium prepared using the Chinese oak mushroom was found to be safe. As residual pesticides, heavy metals, and radioactivity—even in trace amounts—remain concentrated in the human body, continuous verification of the safety of hazardous substances and pollutants during the systematic cultivation and management of these mushrooms is required.

N-nitrosodimethylamine (NDMA) is a potent carcinogen that is frequently detected nitrosamine from water chloramination. This study investigated the occurrence of NDMA and its potential precursor, ranitidine (RNT), in four wastewater treatment plants (WWTPs). Additionally, the effects of chloramination methods and oxidative pretreatment on the NDMA formation potential (FP) were assessed. Concentration levels of NDMA in the WWTPs waters ranged from 2.5 (detection limit) to 72.6 ng/L, while RNT values ranged from 1.32 to 186.9 ng/L. Further study indicated that the NDMA-FPs from chloraminated wastewaters varied between 36.2 and 227.8 ng/L. Nonetheless, chloramination methods and oxidative pretreatment significantly impacted the NDMA-FP levels. For example, breakpoint chlorination and stepwise chloramination promoted NDMA-FP when compared to preformed chloramination, which could be attributed to the formation of dichloramine and chlorine species. In contrast, prechlorination was found to effectively mitigate NDMA-FP, based on integrated ultraviolet (UV) irradiation. Notably, UV irradiation with free chlorine (UV/Cl2) or permanganate (UV/MnO4 -) reduced NDMA-FP by up to 70%. This study suggests that UV/MnO4 - and UV/Cl2 may be used as alternative mitigation strategies for reducing nitrosamine-FP in the water treatment process.

Thermal reduction of graphite oxide (GO) is considered as a prospective method for the preparation of high-performance graphene-based materials. However, this method has certain limitations, and the major is that this exothermic process is difficult to control. In this research, we focused on the kinetic studies of the reduction of graphite oxide using non-isothermal differential calorimetry (DSC) method. Six GO nanocomposites with dyes were tested to study the shift in kinetic parameters. The apparent reaction order is determined to be ca 0.7 for the thermal decomposition of pure GO, while in the presence of dye molecules it increases sometimes reaching a value of 2.0 for higher dye concentrations. Decisively, the thermal decomposition of pure GO can be presented as an intermediate between a zero- and first-order reaction, while the introduction of dye molecules turns a certain part of the energy consumption via the bimolecular pathway. Our research revealed that the process of GO thermal decomposition can be operated and properties of the final product (reduced graphene oxide (rGO) and its derivatives) can be adjusted more precisely using additive molecules, which interact with GO sheets.

고추에서 Colletotrichum scovillei를 검출하고 계수하기 위한 반선택배지가 개발되었다. 기본배지로서 Potatodextrose- agar (PDA)가 사용되었다. 반선택배지의 최종 조성은 부생성곰팡이와 세균을 저해하고, C. scovillei의 생장에 양호할 수 있도록 확립되었다. 반선택배지는 pyribencarb 와 pydiflumetofen 각각 40 μg mL-1와 세균을 방지하기 위한 streptomycin 100 μg mL-1를 포함한다. 배지의 pH는 85% lactic acid로 4.8로 조절했다. 반선택배지에 배양할 때 C. scovillei의 균사생육 저해율은 Fusarium속과 다른 부생균보 다 뚜렷이 낮았다. 반선택배지에 과실과 줄기조직 현탁액 을 평판배양하여 탄저병균이 자연 감염된 식물체로부터 C. scovillei가 검출되었고, 신뢰할 수 있고 정량할 수 있었다. 이것은 자연 감염된 고추조직에서 C. scovillei의 존재를 검출하기 위한 반선택성배지에 대한 처음 보고이다.

The effect of multi-walled carbon nanotubes (MWCNT) coating in the presence of polyethyleneimine (PEI) of different molecular weights (MW) on the interfacial shear strength (IFSS) of carbon fiber/acrylonitrile–butadiene–styrene (ABS) and carbon fiber/epoxy composites was investigated. The IFSS between the carbon fiber and the polymer was evaluated by means of single fiber microbonding test. The results indicated that uses of the carbon fibers uncoated and coated with pristine, low MW PEI-treated, and high MW PEI-treated MWCNT significantly influenced the IFSS of both thermoplastic and thermosetting carbon fiber composites as well as the carbon fiber surface topography. The incorporation of low MW (about 1300) PEI into the carboxylated MWCNT was more effective not only to uniformly coat the carbon fiber with the MWCNT but also to improve the interfacial bonding strength between the carbon fiber and the polymer than that of high MW (about 25,000) PEI. In addition, carbon fiber/epoxy composite exhibited the IFSS much higher than carbon fiber/ABS composite due to the chemical interactions between the epoxy resin and amine groups existing in the PEI-treated MWCNT.

연구는 고등학생이 온라인 수업에서 느끼는 교수실재감이 자기결정성동기의 기본심리욕구를 매개하여 자기조절학습능력에 미치는 영향을 검증하고, 이 변인 간 관계에서 남녀 학생 간 성별에 따른 차이가 있는 지 검증하고자 하였다. 이를 위해 J지역에 위치한 3개 고등학교에 설문지를 배포하였고 최종적으로 383명의 학생의 자료를 구조방정식모형 분석방법을 사용하여 분석하였다. 그 결과 첫째, 온라인 수업상황에서 학생들이 인식하는 교수실재감은 자기결정성동기와 자기조절학습능력에 영향을 미치는 것으로 나타났다. 둘째, 자기결정성 동기의 기본심리욕구 세 가지 하위요인 중 유능성만 온라인 수업에서의 교수실재감과 자기조절학습능력 변인 간에 매개역할을 하는 것으로 나타났다. 셋째, 온라인 수업에서의 학생들이 인지하는 교수실재감과 자기결정성 동기의 기본심리욕구, 자기조절학습능력 간의 구조적 관계에서 남녀 학생 간 성별차이는 나타나지 않았다. 본 연구의 결과는 교사가 온라인 수업 중 학생의 자기조절학습능력을 발달시키기 위해 교수실재감을 높이는 것이 필요하며, 그 과정에서 자기결정성동기의 기본심리욕구 중, 교수실재감과 자기조절학습능력을 매개하고 있는 유능감 뿐 아니라, 매개하지 못한 자율성과 관계성의 기본심리욕구도 강화할 필요가 있음을 시사하고 있다.

The purpose of this study is to measure the levels of eluted and dissolved CO2, and CO, volatile organic substances and radiation composition of Cheongsong mineral water which were collected from November 2019 to July 2020 during the autumn, spring, and summer seasons at collection points located in the upper, middle and lower spring waters. Data of the upper, middle and lower spring waters include the following: the amount of eluted water (average value±standard deviation, mL/min) was 30.07±0.52, 15.03±0.16, 23.73±0.42, and the amount of CO2 gas was 1,000 ppm or more. In addition, there was no detection of CO or total volatile organic substances (TVOC) and the radiation dose was 0.08 to 0.13. μSv/h. A blank test value of 0.08 to 0.10 μSv/h, when compared with the median value, showed a high value of 0.02 μSv/h, and the uranium test results provided by the Cheongsong-gun Office were 0.0118 mg/L (date 2019.06.18) and 0.0091 mg/L (date 2020.06.04.) respectively, which was less than the permission limit of 0.03 mg/L. However, it is believed that further research using more precise devices is needed in order to guarantee the safety and health of the water.