Writing conferences are one-on-one feedback sessions that enable teachers and students to engage in constructive interactions to improve students’ writing. While interacting individually, a teacher can use various feedback strategies to improve the quality of a student’s writing. This study examined how a secondary English teacher elicited students’ self-correction of writing issues during EFL writing conferences conducted in Korean (L1) as part of an after-school English program at a Korean high school. One English teacher and five first-year students participated in writing classes for two weeks during the winter vacation. Their conversations were video-recorded and analyzed using Conversation Analysis. Findings revealed that the teacher elicited the student’s selfcorrection through four key strategies: (1) metalinguistic clues, (2) building on initial corrections, (3) leveraging morphological knowledge, and (4) guiding students through a stepwise construction of sentence elements. This study can enhance our understanding of corrective feedback in secondary EFL writing conferences and offer insights for improving teacher-student feedback interactions.

This study explored factors affecting variability in second language (L2) learning motivation among Korean university students and how they appraised their L2 learning experience. In this study, 85 undergraduate students majoring in English or English education from three universities in Seoul, South Korea, reflected on their past English learning experience. They drew a motigraph and wrote a retrospective reflection essay covering their English learning that spanned over ten years. Researchers divided participants into two groups: a high variability (HV) group and a low variability (LV) group. Data were analyzed using open, axial, and selective coding. Findings suggest thncontextual factors such as the learning method, atmosphere, and situation were main (de)motivational factors for the HV group. In contrast, the LV group was (de)motivated by intrapersonal factors, including the learning context appraisal. These results imply that visualizing long and short-term goals and positive appraisal of the L2 learning experience can help L2 learners maintain a stable pattern in L2 learning motivation.

다결정성 ZIF-8 분리막의 C3H6/C3H8 kinetic 분리 성능 향상을 목적으로 상대적으로 부피가 큰 2, 4-dimethylimidazole (dmIm)이 ZIF-8 구조 내 2-methylimidazole들을 일부 대체한 혼합 리간드 ZIF-8 유사체 분리막을 이차성장법을 이용 하여 제조하였다. 25°C, 1 bar의 feed 압력에서 C3H6/C3H8 (50/50, V/V) 혼합가스를 대상으로 측정된 분리막의 선택도는 ~180이었으며, 이는 기 보고된 대부분의 다결정성 ZIF-8 분리막들의 선택도보다 높았다. 선택도 향상의 원인인 ZIF-8 구조 내 dmIm 도입으로 인한 기공 입구 크기의 축소를 77 K에서의 질소 등온흡착실험과 Maxwell-Stefan model을 이용하여 C3H6 와 C3H8 막투과도 데이터로부터 계산된 확산계수들을 통해 증명하였다.

본 연구에서는 상용 폴리염화비닐을 개질하여 두 종류의 PVC 기반 이온교환용 고분자를 성공적으로 제조하였다. 이후 개질된 두 이온교환 고분자를 활용한 전기방사 공정과 열 압착 공정을 거쳐 2차원 계면(2D-PVC-BPM)과 3차원 접합부 (3D-PVC-BPM)를 갖는 바이폴라막(BPM)을 제조하였다. 제조된 3D-PVC-BPM은 2D-PVC-BPM에 비해 우수한 물 분해 효율 및 안정성을 보였다. 구체적으로, 300 mA cm-2의 고전류 밀도에서 3D-PVC-BPM은 2D-PVC-BPM가 나타낸 전위보다 4.4 V 낮은 8.05 V의 막 전위를 나타냈다. 더욱이, PVC 주쇄가 가진 내화학성 덕분에 3D-PVC-BPM은 가혹한 조건에서도 높은 화 학적 안정성을 보였고, 이는 4 M H2SO4 및 4 M NaOH 용액에 28일간 침지한 후 관측된 질량 손실이 각각 2.8%와 2.1%에 그친 것을 통해 입증되었다. 끝으로, 3차원 접합부가 3D-PVC-BPM에 맞물림(interlocking) 효과와 넓은 계면면적을 제공해준 덕분에 3D-PVC-BPM의 인장 강도는 36 MPa를 초과했고 신장률 또한 약 50%에 이르는 등 우수한 기계적 물성을 나타냈다.

We present optical observations of a nearby Type Ia supernova (SN Ia) 2018kp on January 24 2018, +1.4 days after the estimated first light time. Its host galaxy, NGC 3367, has been under high-cadence monitoring (≲1 day) with the purpose of providing valuable early light curves of supernovae as a primary target of the Intensive Monitoring Survey of Nearby Galaxies (IMSNG; Im et al. 2019). SN 2018kp exhibits the characteristics of a normal SN Ia, with a peak luminosity of MB = −19.0 ± 0.4 mag and Δm15(B) = 1.19 ± 0.03 mag, derived from our long-term light curve analysis. We estimate the host extinction to be high [E(B − V )host = 0.697 ± 0.028 mag], contrasting with its sibling, SN 1986A. We estimate the mass of 56Ni synthesized in the explosion to beMNi = 0.55±0.14M⊙. A single power-law model (tα) describes the rising behavior of the early light curve well, with little evidence of the shock-heated cooling emission. We place upper limits on the radii of the progenitor (Rp ≤ 1.8 R⊙) and the companion star (Rc ≤ 1.9 R⊙ at the optimal or Rc ≤ 19.2 R⊙ at the common viewing angle, respectively) ruling out a large companion such as a red giant. Based on our data, we derive a distance to the host galaxy of 41.38 ± 2.20 Mpc assuming that SN 2018kp follows the Phillips relation.

본 연구는 고등학교 담임교사의 상담 경험에 대한 질적 사례연구를 통해, 담임교사가 학생 상담에서 겪는 다양한 경험과 어려움을 분석하는 것을 목적으로 하고 있다. 연구자는 세 명의 고등학교 담임교 사를 대상으로 인터뷰를 진행하여, 담임교사들이 학생 상담 과정에서 겪는 도전과 극복 방안을 심층적 으로 탐구하였다. 연구의 결과로는 􍾧상담의 접근 방식과 어려움, 역할과 기대에 따른 부담, 학생 이해를 위한 통로, 교사의 성장과 보람􍾨의 네 개의 범주와 􍾧초기 담임교사 시절 경험과 가이드 라인의 부재, 전 문적 상담의 한계, 상담에 대한 학교와 학부모의 기대, 비담임과는 다른 담임교사로서의 부담, 깊이 있 는 이해와 앎의 시간, 진로 탐색을 위한 여정, 정서적 안정의 중요성, 개인의 성장과 변화􍾨, 􍾧상담의 보 람과 동기 부여􍾨의 9개의 중심 주제가 도출되었다. 연구 결과를 바탕으로 교사의 성장과 정서적 안정을 지원하는 방안 모색과 학교 내 상담 환경을 개선하기 위한 제도적 개선 방안을 제시하였다.

Refractory materials, such as molybdenum and niobium, are potential candidates for cladding material due to their high melting temperatures and desirable mechanical properties at higher temperatures than those of zirconium alloys. However, refractory materials have low resistance to oxidation at elevated temperatures. Therefore, this study examined silicide or aluminide surface coatings as protection against rapid oxidation of refractory materials at elevated temperatures for a potential accident-tolerant fuel cladding. Silicide or aluminide layers were formed on refractory metal substrates by using the pack cementation method. The steam oxidation behavior of both coated and uncoated samples was compared by thermogravimetric analysis at 1200°C. The weight changes of the coated samples were greatly reduced than those of uncoated samples. Microstructural analyses demonstrated that the silicide and aluminide layers were oxidized to form a protective surface oxide that prevented rapid oxidation of the refractory substrate at elevated temperatures.

Deep geological repositories (DGR) count amongst the world largest environmental protection projects. They are the internationally advocated reference solution for the long-term management of high-level radioactive waste (HLW) and spent nuclear fuel (SNF). Many countries have engaged in programs to develop their own DGR. In Europe, four countries have passed the important milestone of choosing or announcing the appropriate site for the location of their HLW disposal facilities. Finland has almost finished the commissioning of its DGR and should start industrial disposal operations in 2025. Sweden has authorized the construction of its DGR and is finalizing the licensing document to start construction. France is reviewing the construction license application of its DGR. Switzerland has proposed the location of its DGR and is carrying out the production of the documentation for the license application. These four countries took decades to choose the location for their DGR. The length of this process is explained by 1) the amount of technical investigations and studies that were carried out to first identify, select and then fully characterize the suitable site and 2) the progressive decision-making process defined by their respective legal frameworks, including the participation and engagement of communities and stakeholders.

This study investigated whether calcium (Ca) addition improved the recovery of neodymium (Nd) and dysprosium (Dy) from Nd-Fe-B magnet scrap using magnesium (Mg)-based liquid metal extraction (LME). Traditional LME processes are limited to temperatures up to 850 °C due to oxidation issues, reducing the efficiency of rare earth element (REE) recovery, especially for Dy. By adding 10 wt.% Ca to Mg and increasing the processing temperature to 1,000 °C, we achieved nearly 100% Nd and approximately 38% Dy recovery, compared to 91% and 28%, respectively, with pure Mg at 850 °C. However, excessive Ca addition (20 wt.%) decreased the recovery efficiency due to the formation of stable intermetallic compounds. These results highlight the critical role of Ca in optimizing REE recycling from Nd-Fe-B magnet scrap.

High-entropy alloys (HEAs) represent a revolutionary class of materials characterized by their multi-principal element compositions and exceptional mechanical properties. Powder metallurgy, a versatile and cost-effective manufacturing process, offers significant advantages for the development of HEAs, including precise control over their composition, microstructure, and mechanical properties. This review explores innovative approaches integrating powder metallurgy techniques in the synthesis and optimization of HEAs. Key advances in powder production, sintering methods, and additive manufacturing are examined, highlighting their roles in improving the performance, advancement, and applicability of HEAs. The review also discusses the mechanical properties, potential industrial applications, and future trends in the field, providing a comprehensive overview of the current state and future prospects of HEA development using powder metallurgy.

이 연구는 여고생을 대상으로 외모관심도와 자기표현 욕구가 자아존중감 및 외모관리행동에 미치는 영향을 알아보기 위해 자 기기입식 설문조사 방법을 통해 이루어졌다. 조사 기간은 2024년 8월 1일부터 2024년 9월 20일까지 설문조사를 실시하였으며, 유효표본 200부를 최종 분석자료로 활용하였고 리커트 5점 척도 를 사용하였다. 첫째, 여고생의 외모 관심도와 자기표현 욕구는 모두 자아존중 감에 유의미한 정(+)의 영향을 미치는 것으로 나타나 외모관심도 와 자기표현 욕구가 높을수록 자아존중감도 높아지는 것으로 볼 수 있었다. 둘째, 여고생의 자기표현 욕구가 외모관리행동에 유의미한 정 (+)의 영향을 미치는 것으로 나타나 자기표현 욕구가 높을수록 외모관리행동도 높아지는 것으로 볼 수 있었다. 셋째, 여고생의 자아존중감이 외모관리행동에 유의미한 정(+)의 영향을 미치는 것으로 나타나 자아존중감이 높을수록 외모관리행 동도 높아지는 것으로 볼 수 있었다. 이상의 결과를 볼 때, 부모나 교육자는 여고생들이 외모관리행 동에 대한 올바른 판단하에 외모관심과 자기표현을 과하거나 지 나치지 않게 표출하여 자아존중감 및 외모관리를 할 수 있도록 지도하여야만 할 것이다. 결론적으로 여고생들은 질풍노도의 사춘기 단계에 있고 감정조 절이 미숙하기 때문에 자기표현 단계에서 부정적인 감정에 휘말 릴 수 있으며, 따라서 부모나 교육자는 솔직한 감정을 표출할 수 있는 열린 자세로 외모에 대한 건강한 인식과 올바른 개념을 정 립할 수 있도록 도와야 할 것이다.

자기공명영상은 인체 내부 구조와 병변을 비침습적으로 시각화하는 핵심 의료 영상 기법으로 자리 잡고 있으며, 특히 신경계 및 심혈관계 질환과 같은 복잡한 질병의 진단에서 필수적인 도구로 활용되고 있다. 기존의 자기공명영상 시스 템은 영상의 해상도와 신호대잡음비에서 한계가 있었으나, 최근의 기술 발전은 이러한 한계를 극복하고 진단 정확성 을 높이는 방향으로 나아가고 있다. 고자기장 자기공명영상 시스템의 도입은 해상도와 신호대잡음비를 개선하는 데 기여하고 있으며, 병렬 영상 기법은 촬영 속도를 향상시키면서도 영상 품질의 손실을 최소화한다. 또한, 압축 센싱 (compressed sensing) 기술은 데이터 획득 시간을 줄여 촬영 효율성을 높이는 데 중요한 역할을 하고 있다. 최근 인공지능(AI)의 발전으로, 자기공명영상 데이터에서 초해상도 복원(super-resolution) 및 노이즈 제거와 같은 영상 후처리 기술이 획기적으로 향상되었다. 인공지능 기반의 영상 향상 기술은 저해상도 데이터를 고해상도로 변환하고, 촬영 과정에서 발생할 수 있는 왜곡과 노이즈를 효과적으로 제거하여, 더 정확하고 명확한 진단 영상을 제공한다. 이러한 발전은 단순히 영상의 품질을 높이는 것을 넘어, 임상 진단의 정확성과 효율성을 크게 향상시키고 있으며, 특히 제한된 촬영 시간을 요구하는 응급 상황에서 유용성이 두드러진다. 본 논문에서는 자기공명영상 촬영 기법의 최신 발전과 인공지능 기반 영상 향상 기술의 동향을 여러모로 분석하고, 이들의 임상적 유용성을 조명함으로써 고해 상도 자기공명영상이 의료 분야에서 가지는 의미와 향후 발전 방향을 제시하고자 한다.

Light-weight ceramic insulation materials and high-emissivity coatings were fabricated for reusable thermal protection systems (TPS). Alumina-silica fibers and boric acid were used to fabricate the insulation, which was heat treated at 1250 °C. High-emissivity coating of borosilicate glass modified with TaSi2, MoSi2, and SiB6 was applied via dip-and-spray coating methods and heat-treated at 1100°C. Testing in a high-velocity oxygen fuel environment at temperatures over 1100 °C for 120 seconds showed that the rigid structures withstood the flame robustly. The coating effectively infiltrated into the fibers, confirmed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction analyses. Although some oxidation of TaSi2 occurred, thereby increasing the Ta2O5 and SiO2 phases, no significant phase changes or performance degradation were observed. These results demonstrate the potential of these materials for reusable TPS applications in extreme thermal environments.

This experimental study aimed to determine the anti-obesity effects of burdock(Arctium lapp L.) extract and processed (Beopje) burdock extract in a high fat diet-induced obesity model. When burdock extract was orally administered at a concentration of 250 mg/kg BW and the Beopje burdock extract was administered at 250 and 500 mg/kg BW, they significantly decreased body weights increased by a high-fat diet, improved food efficiency ratio, decreased adipose tissue weight by site, and significantly decreased blood triglycerides, total cholesterol, and LDL-cholesterol levels. Blood ALT and AST contents as liver function-related indices increased by the high fat diet were significantly decreased by the Beopje burdock extract. Results of histological analysis of the liver showed that the Beopje burdock extract alleviated fatty liver phenomenon induced by a high-fat diet. In addition, levels of blood TNF-α, IL-6, and IL1-β increased by a high-fat diet were significantly decreased by ALB-L and ALB-H. Therefore, Beopje burdock extract can improve obesity in a high-fat diet-induced obese animal model by improving blood lipids and blood biochemical indices, increasing body water, and decreasing body fat more than the burdock extract.

본 연구에서는 이온성 물질 제거와 재생을 동시 수행하는 바이폴라막에 대한 운전 조건에 따른 성능 영향과 고회 수율을 위한 재생 조건을 연구하였다. 유입수의 농도와 유량이 증가할수록 제거율이 빠르게 감소하였으며 제거율 80% 지점 까지 유입수 농도 300 mg/L에서 최대의 TDS 제거용량을 나타내었고, 유입수 유량은 낮을수록 더 많은 TDS 제거용량을 나 타내었다. 낮은 전압에서는 제거율이 급격하게 감소하였고 전압이 높아질수록 제거율이 증가하지만, 일정 수준 이상의 전압 에서는 추가적인 제거율 향상을 보이지 않았다. 한편 재생을 위한 전압은 75 V로 선정하였는데, 이 이상의 재생 전압에서는 온도의 급격한 상승 및 이로 인한 바이폴라막의 손상이 관찰되었다. 재생 시 재생수의 공급을 최소화하기 위한 다양한 운전 모드가 평가되었고 70%의 고회수율을 구현할 수 있는 재생모드를 제안하였다.

고온 구동형 고분자 전해질 막 연료전지(high temperature polymer electrolyte membrane fuel cell, HT-PEMFC)는 구동 중 발생되는 불순물에 대한 내성이 높고 물관리가 용이하며 고순도의 가스를 연료로 사용하지 않아도 되는 장점을 갖는 다. HT-PEMFC는 인산이 도핑된 막을 통해 수소이온이 전도되기 때문에 전해질 막의 높은 인산의 유지율이 요구된다. 본 총 설에서는 인산의 침출을 방지하여 고성능의 HT-PEMFC용 고분자 전해질 막을 개발하기 위해 1) 인산이 도핑된 전해질 막의 인산 침출에 영향을 미치는 요소를 파악한 후, 이를 개선하기 위해 2) 폴리벤즈이미다졸 기반 막과 인산과의 상호작용을 강 화하여 인산 침출을 방지할 수 있도록 고분자 구조 설계를 진행한 연구와 3) 이오노머의 이온교환 작용기와 인산과의 이온 쌍 상호작용을 통해 인산의 침출을 방지할 수 있도록 이오노머 구조 설계를 진행한 연구들에 대해 살펴보고자 한다.

In this study, in order to develop an eco-friendly filtration method that considers the health and safety of the aquatic ecosystem by differentiating it from chemical methods (coagulants, oxidants, etc.), which are mainly used as methods for managing the removal of algae in the algal bloom stage, an effective separation membrane for algae removal was reviewed, an appropriate technology was proposed through field application, and the effect of algae removal was evaluated. The membrane used was applied in the field by constructing an optimal technology through auxiliary facilities with an immersion tubular membrane and a pressurized tubular membrane resistant to adhesive pollutants and algae. As a result, the strong characteristics of Fouling (blocking) by adhesive algae were confirmed, and the effect of removing algae and particulate matter in the immersion type tubular membrane was 99% chlorophyll-a (Chl-a), 99.2% suspended solid (SS), and 96.7% of pressurized tubular membranes, showing excellent effects in removing algae and particulate organic matter. In addition, as a result of field application to eutrophic reservoirs where high-density algae are distributed, it was confirmed that stable operation of algae was possible during the process of filtering, separation, and concentration.

The winter forage triticale (x Triticosecale Wittmack) cultivar ‘Onggoljin’ was developed in 2018 by Central Area Crop Breeding Division, the National Institute of Crop Science, Rural Development Administration, as a winter forage. ‘Onggoljin’ has green leaves with medium length and narrower blade width compared to ‘Joseong’. ‘Onggoljin’ has shorter length spikes, a slightly longer awn than ‘Joseong’, and it’s anther without anthocyanin color. The seeds of ‘Onggoljin’ was shorter in both length and thickness than those of ‘Joseong’, with a yellowish-brown grain coat color. The heading date of ‘Onggoljin’ was at April 23 nationwide on average, two days later than ‘Joseong’. It exhibits stronger winter hardness, and simmilar lodging and desease resistance compared to ‘Joseong’. The plant height of ‘Onggoljin’ was longer than that of ‘Joseong’, and its fresh matter yield and dry matter yield were 46.31 tons/ha and 15.75 tons/ha, respectively, representing 18% and 17% higher than ‘Joseong’. The forage quality characteristics of ‘Onggoljin’ at late milky stage were crude protein content of 6.2%, neutral detergent fiber content of 59.5%, acid detergent fiber content of 34.4%, and total digestible nutrients content of 61.8%, and the silage quality was grade 2. The grain yield of ‘Onggoljin’ was 6.57 tons per ha.

The purpose of this study was to analyze English subject-specific descriptions through text mining, examine their alignment to the curriculum achievement standards, and ultimately support students’ educational growth. We collected English subject-specific descriptions for 1,030 tenth-graders from general high schools in City A, and keywords and contexts were extracted using TF, TF-IDF, phi coefficient analysis, and trigram analysis. The results revealed that the subject-specific descriptions frequently neglected the following aspects of learning and instruction in curriculum achievement standards: familiar and general themes, conversation and listening skills, language use across different types of information, and proper email writing. Although descriptions are intended to reflect students’ actual achievement levels, those for lower achievement levels (i.e., D and E) were often overstated. Improvements are necessary to ensure closer alignment between the descriptions and the curriculum achievement standards, with particular emphasis on the accurate representation of lower achievement levels. Based on the findings, we discussed potential improvement strategies for educational authorities to consider and implement.

To prevent and improve various metabolic-related diseases caused by modern high-energy eating habits, alternative meats using mushroom materials are being researched. In this study, high-moisture (HMMA) and low-moisture meat analog (LMMA) were prepared using Pleurotus ostreatus fruiting body (oyster mushroom) powder and isolated soy protein as the raw materials in a co-rotating twin-screw extruder. Textural characteristics tended to decrease as the oyster mushroom content increased. HMMA exhibited a fibrous structure similar to that of chicken, whereas LMMA did not show a characteristic fibrous structure. The water absorption capacity of substitute meat decreased with increasing mushroom powder content. Radical scavenging activity, a measure of antioxidant activity, increased with increasing mushroom content in the substitute meat because of the influence of antioxidant components such as polyphenols in mushrooms. In terms of the prepared substitute meat's color, it was less vibrant and lacked intensity, which is thought to make it less appealing to customers. To address this issue, more ingredients need to be investigated.