• 영어영문학
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• 제57권6호
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• pp.977-998
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• 2011

The purpose of this study is to investigate prospective teachers' perceptions of the peer review comments readily available to them during the writing process in a teacher training class. Given these needs, we employ a qualitative method of inquiry giving voice to the learner's own view of peer feedback. The data we wish to consider is first-person narratives elicited from four EFL college students, who are prospective teachers of English. With regard to the EFL students' narrative considered here, all were attentive to the feedback they received. Moreover, the way in which these EFL writers talk about peer response activity reflects that they still welcome peer feedback because of the benefits to be accrued from it. Although this study, covering only four EFL students in total, can hardly be considered conclusive, we attempt to offer a synthesis of their stories. First of all, students indicate that they received responses from "authentic readers" (Mittan 1989, 209). We do note, consequently, that students gain a clear understanding of readers' needs by receiving feedback on what they did well and on what seems unclear. Perhaps the greater effect of peer feedback claimed by these students is that they take active roles in utilizing peer comments. Since they feel uncertain about the validity of their classmates' responses, students feel that they have autonomy over their own text and can make their own decisions on whether they should accept their peer comments or not. This contrasts with their treatment of teacher comments that they accept begrudgingly even if they disagree with them. Four EFL writers talked a lot, typically in a positive way, about peer response to their writing, yet they have expressed reservations about the extent to which they should put any credence in comments offered by their fellow students. Perhaps this is because their fellow students are still developing writers and EFL learners. In turn, they were sometimes reluctant to accept the peers' comments. Thus, in EFL contexts, L1 use can be suggested during peer feedback sessions. In particular, we have come to feel that L1 use enables both reviewers and receivers to have more productive peer review experiences. Additionally, we need to train students not "to see peer feedback as potentially bad advice" (Silva et al. 2003, 111). Teachers should focus on training students to utilize their peers' comments. Without such training, students will either ignore feedback or fail to use it constructively.

• 마이크로전자및패키징학회지
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• 제30권4호
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• pp.8-16
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• 2023

디바이스 소형화의 한계에 다다르면서, 이를 극복할 수 있는 방안으로 차세대 패키징 기술의 중요성이 부각되고 있다. 병목 현상을 해결하기 위해 2.5D 및 3D 인터커넥트 피치의 필요성이 커지고 있는데, 이는 신호 지연을 최소화 할 수 있도록 크기가 작고, 전력 소모가 적으며, 많은 I/O를 가져야 하는 등의 요구 사항을 충족해야 한다. 기존 솔더 범프의 경우 미세화 한계와 고온 공정에서 녹는 등의 신뢰성 문제가 있어, 하이브리드 본딩 기술이 대안책으로 주목받고 있으며 최근 Cu/SiO₂ 구조의 문제점을 개선하고자 SiCN에 대한 연구 또한 활발히 진행되고 있다. 해당 논문에서는 Cu/SiO₂ 구조 대비 Cu/SiCN이 가지는 이점을 전구체, 증착 온도 및 기판 온도, 증착 방식, 그리고 사용 가스 등 다양한 증착 조건에 따른 SiCN 필름의 특성 변화 관점에서 소개한다. 또한, SiCN-SiCN 본딩의 핵심 메커니즘인 Dangling bond와 OH 그룹의 작용, 그리고 플라즈마 표면 처리 효과에 대해 설명함으로써 SiO₂와의 차이점에 대해 기술한다. 이를 통해, 궁극적으로 Cu/SiCN 하이브리드 본딩 구조 적용 시 얻을 수 있는 이점에 대해 제시하고자 한다.

• 벤처창업연구
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• 제17권6호
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• pp.39-50
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• 2022

본 논문에서는 시그널링 이론을 기반으로 스타트업이 정부 R&D 지원금을 받았을 때 벤처 투자를 유치하게될 가능성이 높아지는지 살펴보았다. 먼저 벤처캐피털 투자자들의 투자 의사결정 과정과 투자 결정에 영향을 미치는 조건들을 선행연구를 통해 이해하였다. 정부 지원금의 시그널 효과와 정부 R&D 지원금의 민간자금 투자 유도 효과에 대한 선행연구를 토대로 정부 R&D 지원이 스타트업의 벤처투자를 유도하는 메커니즘을 밝혔다. 그리고 정부 R&D 지원이 실제 벤처투자를 유도하는 효과가 있는지 검증하기 위해 2021년 벤처기업으로 인증받은 업력 7년 이하의 스타트업 데이터를 바탕으로 실증분석을 수행하였다. 정부 R&D 지원과 벤처투자에 모두 영향을 미칠 수 있는 요인들을 제거하고 정부 R&D 지원이 벤처투자 유도에 미치는 순효과를 분석하기 위해 성향점수매칭법과 이중차분법을 순차적으로 적용하는 분석방법을 활용하였다. 실증분석 결과 창업 후 정부 R&D 지원금을 많이 받은 기업일수록 벤처 투자를 유치할 확률이 높아지며, 최초 정부 R&D 과제를 수행한 뒤 2년이 지난 시점부터 정부 R&D 지원의 벤처투자 유도 효과가 발생해 최초 과제수행 후 3년이 지난 시점까지 지속되는 것을 알 수 있었다. 본 논문의 결과는 정부 R&D 사업이 벤처투자 생태계에도 영향을 줄 수 있다는 것을 입증해 스타트업을 대상으로하는 정부 R&D 사업 기획에 정책적인 시사점을 줄 수 있을 것이다. 또한 신규 자금 조달이 필요한 스타트업에도 전략적 시사점을 줄 수 있을 것으로 기대된다.

• Animal Bioscience
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• 제37권3호
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• pp.500-508
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• 2024

Objective: Due to current selection practices for increased egg production and peak persistency, the production profile, age at maturity, and body weight criteria for commercial layers are constantly changing. Body weight and age at the time of photostimulation will thus always be the factors that need to be adequately addressed among various production systems. The current study was carried out to determine the effects of pullets' body weight (low, medium, and heavy) on their performance, welfare, physiological response, and hormonal profile. Methods: With regard to live weight, 150 16-week-old pullets were divided into three groups using a completely randomized design (CRD) and held until the 50th week. One-way analysis of variance was used to evaluate the data under the CRD, and the least significant difference test was used to distinguish between treatment means. Results: In comparison to the medium and light birds, the heavy birds had higher body weight at maturity, an earlier age at maturity, and higher egg weight, eggshell weight, eggshell thickness, egg yolk index, breaking strength, egg surface area, egg shape index, egg volume, and hormonal profile except corticosterone. However, the medium and light birds had lower feed consumption rates per dozen eggs and per kilogram of egg mass than the heavy birds. Light birds showed greater body weight gain, egg production, and egg specific gravity than the other categories. At 20 weeks of age, physiological response, welfare aspects, and catalase were non-significant; however, at 50 weeks of age, all these factors-aside from catalase-were extremely significant. Conclusion: The findings of this study indicate that layers can function at lower body weights during photostimulation; hence, dietary regimens that result in lighter pullets may be preferable. Additionally, the welfare of the birds was not compromised by the lighter weight group.

• 대한두개안면성형외과학회지
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• 제25권2호
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• pp.62-70
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• 2024

Background: The management of cleft lip and palate aims at improving the patient's aesthetic and functional outcomes. Delaying primary repair can disrupt the patient's functional status. Long-term follow-up is essential to evaluate the need for secondary repair or revision surgery. This article presents the epidemiology of cleft lip and palate, including comprehensive patient characteristics, the extent of delay, and secondary repair at our institutional center, the Bandung Cleft Lip and Palate Center, Faculty of Medicine, Universitas Padjadjaran, Bandung, Indonesia. Methods: This retrospective study aimed to determine the epidemiology and recurrence rates of cleft lip and palate at the Bandung Cleft Lip and Palate Center, Indonesia, from January 2007 to December 2021. The inclusion criteria were patients diagnosed with cleft lip and/or palate. Procedures such as labioplasty, palatoplasty, secondary lip and nasal repair, and alveolar bone grafting were performed, and data on recurrence were available. Results: In total, there were 3,618 patients with cleft lip and palate, with an age range of 12 months to 67 years. The mean age was 4.33 years, and the median age was 1.35 years. Males predominated over females in all cleft types (60.4%), and the cleft lip was on the left side in 1,677 patients (46.4%). Most cases were unilateral (2,531; 70.0%) and complete (2,349; 64.9%), and involved a diagnosis of cleft lip and palate (1,981; 54.8%). Conclusion: Delayed primary labioplasty can affect daily functioning. Primary repair for patients with cleft lip and palate may be postponed due to limited awareness, socioeconomic factors, inadequate facilities, and varying adherence to treatment guidelines. Despite variations in the timing of primary cleft lip repair (not adhering to the recommended protocol), only 10% of these patients undergo reoperation. Healthcare providers should prioritize the importance of the ideal timing for primary repair in order to optimize physiological function without compromising the aesthetic results.

• 자원환경지질
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• 제57권2호
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• pp.263-270
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• 2024

광산배수 슬러지를 대상으로 응집제와 탈수튜브를 이용한 슬러지 탈수시스템(이하 KOMIR-Tube 시스템)의 탈수율 향상을 위한 영향인자를 평가하였다. 실험은 KOMIR-Tube 시스템으로 탈수 시 함수율 90 % 이상인 semi-active 시설 슬러지를 대상으로 하였다. 실내실험을 통해 응집제 및 투입량을 결정하였고, 현장실험을 통해 탈수율을 확인하였다. 실내실험 결과, 슬러지 탈수처리 시 응집제 선정은 침강성(sedimentation) 이외 여과성(filterability)을 같이 평가해야 하고, 이때 형성된 플럭의 적정 크기는 최소 0.7 mm 이상의 크기를 유지해야 탈수율을 향상할 수 있었다. KOMIR-Tube 시스템을 이용한 현장실험 결과, 슬러지 함수율은 강우 및 습도 등 환경적 기후 조건에 영향을 받는 것으로 분석되었다. 이에 슬러지 탈수처리는 강우량과 습도가 낮은 4월~5월에 수행하는 것이 적합한 것으로 판단된다. 또한, 슬러지의 주요 구성광물 결정도에 따라 탈수율 차이를 보였다. 특히 철수산화물 중 페리하이드라이트보다 침철석 구성비가 높은 경우, 탈수율이 높은 것으로 나타났다. 이는 페리하이드라이트의 결정도가 침철석 보다 낮고 결정형태가 뚜렷하지 않기 때문으로 판단된다. 침철석은 결정도가 높고 침상을 이루고 있어 응집 및 탈수율에 영향을 미치는 것으로 보인다. KOMIR-Tube 시스템을 이용한 광산배수 슬러지 탈수 시 탈수율에 영향을 미치는 인자는 응집제, 기후조건, 결정성 광물의 존재 유무 그리고 철화합물의 결정도 및 입자 형태로 나타났다.

• 대한치위생과학회지
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• 제1권1호
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• pp.47-55
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• 2018

The purpose of this study was to examine the influence of oral health education experience on needs for oral health education in children and adolescents in elementary and secondary schools. A self-administered survey was conducted on the students in elementary, middle and high schools located in the city of Mokpo, South Jeolla Province, from October 1 to 31, 2018. The data that were collected from 327 students were analyzed by SPSS 21.0. Statistical data on frequency, percentage, mean and standard deviation were obtained, and t-test, one-way ANOVA, correlation analysis and logistic regression analysis were carried out. The findings of the study were as follows: First, the subjects got 2.25 on a three-point scale in self-rated oral health status. This score was above average, which indicated that the students thought they were in good oral health. As for problems with oral health, dental caries was given the highest score of 2.48 on a five-point scale, followed by oral malodor with 2.35. Second, the students who experienced oral health education accounted for 69.1 percent, and the students who felt the need for this education represented 82.6 percent. As for educational content desired, the biggest group of 57.8 percent hoped to learn about how to prevent and manage dental caries, and the second largest group of 17 percent wanted to learn about how to take care of oral health during orthodontic treatment. Third, as a result of investigating the state of oral health education by the grade of school, the elementary school students had more oral health education experience than the middle and high school students, and the middle school students placed the most importance on the necessity of oral health education. The differences were statistically significant. Fourth, as a result of analyzing the correlation between oral health education experience and the necessity of oral health education, the students who had more oral health education experience asked more for this education, which implies that there was a statistically significant positive correlation. The findings of the study ascertained that oral health education should be provided for students in childhood and adolescence to boost the level of their oral health knowledge and change their oral health attitude in a positive manner. If oral health practice programs that connect schools, local communities and families with one another are developed to guide the oral health behaviors of teenagers in the right direction, it will make a contribution to the promotion of oral health.

• Structural Engineering and Mechanics
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• 제90권6호
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• pp.551-568
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• 2024

The present study deals with static and dynamic behaviors including forced vibrations of an elastic rectangular nano plate on the two-parameter foundation. Firstly, the rectangular plate is assumed to be subjected to uniformly distributed and eccentrically applied concentrated loads. The governing equations of the problem are derived by considering the dynamic response of the plate, employing a series of the Chebyshev polynomials for the displacement function and applying the Galerkin method. Then, effects of the non-essential boundary conditions of the plate, i.e., the boundary conditions related to the shearing forces, the bending moments and the corner forces, are included in the governing equation of motion to compensate for the non-satisfied boundary conditions and increase the accuracy of the Galerkin method. The approximate numerical solution is accomplished using an iterative process due to the non-linearity of the unilateral property of the two-parameter foundation. The plate under static concentrated load is investigated in detail numerically by considering a wide range of parameters of the plate and the foundation stiffnesses. Numerical treatment of the problem in the time domain is carried out by assuming a stepwise variation of the concentrated load and the linear acceleration procedure is employed in the solution of the system of governing differential equations derived from the equation of motion. Time variations of the contact region and those of the displacements of the plate are presented in the figures for various numbers of the two-parameter of the foundation, as well as the classical and nano parameters of the plate particularly focusing on the non-linearity of the problem due to the plate lift-off from the unilateral foundation. The effects of classical and nonlocal parameters and loading are investigated in detail. Definition of the separation between the plate and the two-parameter foundation is presented and applied to the given problem. The effect of the lift-off on the static and dynamic behavior of the rectangular plate is studied in detail by considering various loading conditions. The numerical study shows that the effect of nonlocal parameters on the behavior of the plate becomes significant, when nonlinearity becomes more profound, due to the lift-off of the plate. It is seen that the size effects are significant in static and dynamic analysis of nano-scaled rectangular plates and need to be included in the mechanical analyses. Furthermore, the corner displacement of the plate is affected more significantly from the lift-off, whereas it is less marked in the time variation of the middle displacement of the plate. Several numerical examples are presented to examine the sensibility of various parameters associated with nonlocal parameters of the plate and foundation. Both stiffening and softening nonlocal parameters behavior of the plate are identified in the numerical solutions which show that increasing the foundation stiffness decreases the extent of the contact region, whereas the stiffness of the shear layer increases the contact region and reduces the foundation settlement considerably.

• 한국터널지하공간학회 논문집
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• 제26권3호
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• pp.209-222
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• 2024

토압식(Earth Pressure Balance) 쉴드 TBM (Tunnel Boring Machine)은 기계화 터널 굴착 공법 중 이수식(Slurry) 쉴드 TBM에 비하여 슬러리 처리 시설을 필요하지 않아 설비가 간단하고 진동과 소음이 적어 최근에 터널 시공에 널리 사용되고 있다. 토압식 쉴드 TBM으로 터널 굴착 시 첨가제를 활용하여 굴착토 물성을 개선하는 쏘일 컨디셔닝(soil conditioning) 기법을 적용하며, 이를 통해 토압식 쉴드 TBM을 적용할 수 있는 지반의 범위를 확장할 수 있다. 본 연구에서는 쏘일 컨디셔닝을 위한 첨가제로 주로 사용되는 폴리머를 대체할 수 있는 바이오폴리머(biopolymer)의 일종인 잔탄검(xanthan gum)의 적용성을 검토하였다. 바이오폴리머란 생물학적 기원으로 생성된 폴리머로써 모두 생분해가 가능하다. 환경에 유해한 성분을 함유하고 있는 일반 폴리머(폴리아크릴산계 폴리머)와 달리 잔탄검은 유독성이 거의 없고 환경에 미치는 영향이 적어 친환경 소재로 각광받고 있다. 슬럼프 시험을 통해 유사한 워커빌리티(workability)를 보이는 시험조건을 선정하고, 실내 가압 베인전단 시험을 통해 유동학적(rheological) 특성을 평가하였다. 유사한 슬럼프 값을 보이더라도 잔탄검의 함유량이 증가할수록 유동곡선(flow curve)상에 첨두강도가 감소하는 경향이 나타났으며, 이를 통해 잔탄검 함량과 첨두강도 사이의 상관관계를 도출하였다. 일반 폴리머를 잔탄검으로 대체한다면 환경친화적이라는 장점과 더불어 장비 부하를 감소시켜 안정적인 TBM 운용이 가능할 것이다.

• Advances in aircraft and spacecraft science
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• 제11권1호
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• pp.83-103
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• 2024

Adhesive bonding is currently widely used in many industrial fields, particularly in the aeronautics sector. Despite its advantages over mechanical joints such as riveting and welding, adhesive bonding is mostly used for secondary structures due to its low peel strength; especially if it is simultaneously exposed to temperature and humidity; and often presence of bonding defects. In fact, during joint preparation, several types of defects can be introduced into the adhesive layer such as air bubbles, cavities, or cracks, which induce stress concentrations potentially leading to premature failure. Indeed, the presence of defects in the adhesive joint has a significant effect on adhesive stresses, which emphasizes the need for a good surface treatment. The research in this field is aimed at minimizing the stresses in the adhesive joint at its free edges by geometric modifications of the ovelapping part and/or by changing the nature of the substrates. In this study, the finite element method is used to describe the mechanical behavior of bonded joints. Thus, a three-dimensional model is made to analyze the effect of defects in the adhesive joint at areas of high stress concentrations. The analysis consists of estimating the different stresses in an adhesive joint between two 2024-T3 aluminum plates. Two types of single lap joints(SLJ) were analyzed: a standard SLJ and another modified by removing 0.2 mm of material from the thickness of one plate along the overlap length, taking into account several factors such as the applied load, shape, size and position of the defect. The obtained results clearly show that the presence of a bonding defect significantly affects stresses in the adhesive joint, which become important if the joint is subjected to a higher applied load. On the other hand, the geometric modification made to the plate considerably reduces the various stresses in the adhesive joint even in the presence of a bonding defect.