To investigate L2 adolescent learners’ use of machine translation (MT), an MT error correction (EC) test was developed, based on the analysis of MT errors arising from translating the learners’ L1 of middle school EFL textbooks. Learners were also asked to report on their use of MT EC strategies on the EC task. Results indicated that mistranslated sentence and verb tense are the most difficult types of MT errors to correct. Furthermore, to resolve MT errors, guessing from context and literal translations were the two most frequently employed EC strategies. When multiple regression analysis was conducted to examine the contribution of EC strategies to the learners’ ability to correct errors, the mid proficiency learners’ reliance on literal translations and the low proficiency learners’ use of multiple EC strategies were positively associated with improved corrections of MT errors. The results of the study are discussed in light of how L2 learners need to develop competence for using MT in L2 writing.

Inaccurate amounts of active ingredients in disinfectants can result in inefficiency or in potential toxicity to the environment and living organisms. This may lead to disinfection failure, and consequently, biosecurity failure. To ensure the efficiency of disinfectants and their ongoing compliance with safety and quality requirements, continuous and systematic post-market surveillance studies are needed. Herein, the content of ten commercial disinfectants purchased in 2021 was analyzed. Selective analytical techniques, such as automated titration, colorimetry, and high-performance liquid chromatography, were used to evaluate the content of several active ingredients present in disinfectants, such as potassium peroxymonosulfate, benzalkonium chloride, glutaraldehyde, phosphoric acid, citric acid, and malic acid. The obtained values were then compared with the label claims; the active ingredient contents of all disinfectants were within the acceptable range of 90–120% of the label claim.

Vaccinations, surveillance, quarantine, and disposal of the infected poultry are the common strategies for prevention and control of the highly infectious poultry diseases; however, many pathogens still persist and are potential causes threatening the nationwide spread of poultry diseases. A strict biosecurity strategy including disinfection is the key to control the spread of avian pathogens, such as the Newcastle disease virus (NDV). It is important to select and use the disinfectants whose efficacy and the effective concentrations against the specific pathogens are known. Therefore, in the present study, we evaluated the virucidal efficacy of five active substances of commercial disinfectants, namely potassium peroxymonosulfate (PPMS), sodium dichloroisocyanurate (NaDCC), glutaraldehyde (GLT), benzalkonium chloride (BZK), and didecyldimethylammonium chloride (DDAC), that are used against NDV. Further, we validated the efficacy of eight pre-approved disinfectants. The minimal virucidal concentrations of the active substances against NDV were as follows: PPMS, 2.50 g/L; NaDCC, 2.00 g/L; GLT, 0.40 g/L; BZK, 2.00 g/L, and DDAC, 1.00 g/L. Furthermore, all the eight disinfectants were found to be effective against NDV at the recommended concentrations, thereby confirming that the active substances are functional against NDV. This is the first study reporting the virucidal activity of the active substances of commercial disinfectants against NDV, in accordance with the Animal and Plant Quarantine Agency guidelines, in South Korea. The results of the virucidal efficacy testing of chemical disinfectants from this study will help poultry industries implement improved strategies for controlling infection.

Herein, we report significantly enhanced mechanical properties and thermal conductivity of polyimide (PI) by incorporating a small amount (0.01 wt %) of individualized boron-doped high-quality graphene as a filler. The boron-doped expandable graphite (B-EG) was synthesized by mixing boric acid ( H3BO4) with expandable graphite (EG) and thermally treating the mixture at 2450 °C for 30 min using a graphite furnace in an argon atmosphere. The boron-doped graphene (B-g) was prepared by the solution-phase exfoliation of B-EG with an ultrasonication process, which is a method to obtain individualized graphene as well as few-layer graphene. The PI nanocomposites were prepared using the obtained graphene. The PI nanocomposites synthesized with high-quality B-graphene (B-g) showed enhanced mechanical properties and thermal conductivity compared to those of pure PI due to the doping effects and strong interfacial interactions between graphene and the PI matrix.

본 연구는 감마스펙트럼 비율을 이용한 매립된 선원의 깊이 평가방법 개발 및 적용성 확인을 위해 진행되었다. 이를 위해 현장측정 HPGe 계측기 및 MCNP 전산모사를 이용하여 137Cs, 60Co, 152Eu 선원의 매질 내 깊이와 계측거리에 따른 Peak to Compton, Peak to Valley 비율(Q)의 변화를 평가하였다. 해당 결과를 이용해 계측거리 50 cm를 기준으로 PTV 및 PTC 비율(Q)과 매립 선원의 깊이 간의 상관 식을 도출하였다. 그리고 PTC 및 PTV 방법 이용 시 계측거리 변화에 따른 민감도를 평가한 결과, 50 cm 기준으로 계측거리가 20 cm로 감소할 경우 오차가 3 ~ 4 cm까지 증가하였다. 하지만 100 cm로 증가할 경우 계측거리에 의한 영향이 미미함을 확인하였다. 그리고 PTV 및 PTC 방법과 피크 영역의 계수율 변화를 통해 선원의 깊이를 평가하는 Two distance measurement 방법을 상호 비교하였다. 평가 결과 PTV 및 PTC 방법은 최대 1.87 cm의 오차, Two distance measurement 방법은 최대 2.69 cm의 오차를 나타내어 PTV, PTC 방법의 정확도가 비교적 높음을 확인하였다. 선원의 수평 방향 위치 변화 민감도 평가 결과 Two distance measurement 방법은 선원이 off-center 방향으로 30 cm 이동하였을 경우 최대 오차가 25.59 cm로 나타났다. 반면 PTV 및 PTC 방법은 최대 오차 8.04 cm로 현장 적용 시 높은 정확도를 나타낼 것으로 예상된다. 그리고 PTC 방법은 동일 시간 측정 시 다른 방법과 비교하여 낮은 표준편차를 나타내 신속한 평가가 가능할 것으로 기대된다.

The recent study of Chae et al. (2017) found a one-to-one correspondence between plasma blobs out owing along a ray formed after a coronal mass ejection (CME) and small X-ray ares. In the present work, we have examined the spatial conguration and the eruption process of the ares that are associated with the blobs by analyzing EUV images and magnetograms taken by the SDO/AIA and HMI. We found that the main are and the successive small ares took place in a quadrupolar magnetic conguration characterized by predominant magnetic elds of positive polarity, two minor magnetic fragments of negative polarity, and a curved polarity inversion line between them, which suggests that the formation process of the blobs may be similar to that of the parent CME. We also found that the successive ares resulted in a gradual change of the quadrupolar magnetic conguration, and the relevant migration of aring kernels. The three-dimensional geometry and the property of the current sheet, that is often supposed to be embedded in an observed post-CME ray, seem to keep changing because of mutual feedback between the successive ares and the temporal change of the magnetic eld conguration. Our results suggest that the observed post-CME rays may not re ect the characteristics of the current sheet responsible for the impulsive phase of the are.

This study presents how two types of integrated science and engineering lessons affect students’ engineering problem solving skills and their perceptions of engineering. In total, 146 middle school students participated in this study. Eighty-six students participated in the Type I lesson (complete engineering design lesson with a science knowledge application) and 60 students participated in the Type II lesson (engineering design without a science knowledge application). Two main datasets, (1) students’ Creative Engineering Problem Solving Propensity (CEPSP) measurement scores and (2) open-ended survey questions about students’ perceptions of engineering, were collected before and after the lessons. The results of this study show that after participating in the Type I lesson, students’ CEPSP scores significantly increased, whereas the CEPSP scores of the students who participated in the Type II lesson did not increase significantly. In addition, students who participated in the Type I lesson perceived engineering and the engineering integrated science lesson differently compared to the students who participated in the Type II lesson. The results of this study show that engineering integrated science, technology, engineering & mathematics (STEM) lessons should include a complete engineering design and a science knowledge application to improve students’ engineering problem solving skills.