• Smart Structures and Systems
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• 제32권6호
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• pp.349-358
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• 2023

Real-Time Hybrid Testing (RTHT) requires the numerical substructure calculations to be completed within the defined integration time interval due to its real-time loading demands. For solving the problem, A Real-Time Hybrid Testing based on Restart-Loading Technology (RTHT-RLT) is proposed in this paper. In the proposed method, in case of the numerical substructure calculations cannot be completed within the defined integration time interval, the experimental substructure was returned back to the initial state statically. When the newest loading commands were calculated by the numerical substructure, the experimental substructure was restarted loading from the initial state to the newest loading commands so as to precisely disclosing the dynamic performance of the experimental substructure. Firstly, the methodology of the RTHT-RLT is proposed. Furthermore, the numerical simulations and experimental tests on one frame structure with a viscous damper are conducted for evaluating the feasibility and effectiveness of the proposed RTHT-RLT. It is shown that the proposed RTHT-RLT innovatively renders the nonreal-time refined calculation of the numerical substructure feasible for the RTHT. The numerical and experimental results show that the proposed RTHT-RLT exhibits excellent performance in terms of stability and accuracy. The proposed RTHT-RLT may have broad application prospects for precisely investigating the dynamic behavior of large and complex engineering structures with specific experimental substructure where a restarting procedure does not affect the relevant hysteretic response.

• Current Optics and Photonics
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• 제7권6호
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• pp.608-637
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• 2023

The initial motivation in colloid science and engineering was driven by the fact that colloids can serve as excellent models to study atomic and molecular behavior at the mesoscale or microscale. The thermal behaviors of actual atoms and molecules are similar to those of colloids at the mesoscale or microscale, with the primary distinction being the slower dynamics of the latter. While atoms and molecules are challenging to observe directly in situ, colloidal motions can be easily monitored in situ using simple and versatile optical microscopic imaging. This foundational approach in colloid research persisted until the 1980s, and began to be extensively implemented in optics and photonics research in the 1990s. This shift in research direction was brought by an interplay of several factors. In 1987, Yablonovitch and John modernized the concept of photonic crystals (initially conceptualized by Lord Rayleigh in 1887). Around this time, mesoscale dielectric colloids, which were predominantly in a suspended state, began to be self-assembled into three-dimensional (3D) crystals. For photonic crystals operating at optical frequencies (visible to near-infrared), mesoscale crystal units are needed. At that time, no manufacturing process could achieve this, except through colloidal self-assembly. This convergence of the thirst for advances in optics and photonics and the interest in the expanding field of colloids led to a significant shift in the research paradigm of colloids. Initially limited to polymers and ceramics, colloidal elements subsequently expanded to include semiconductors, metals, and DNA after the year 2000. As a result, the application of colloids extended beyond dielectric-based photonic crystals to encompass plasmonics, metamaterials, and metasurfaces, shaping the present field of colloidal optics and photonics. In this review we aim to introduce the research trajectory of colloidal optics and photonics over the past three decades; To elucidate the utility of colloids in photonic crystals, plasmonics, and metamaterials; And to present the challenges that must be overcome and potential research prospects for the future.

• Journal of Periodontal and Implant Science
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• 제54권1호
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• pp.3-12
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• 2024

Deep learning (DL) offers promising performance in computer vision tasks and is highly suitable for dental image recognition and analysis. We evaluated the accuracy of DL algorithms in identifying and classifying dental implant systems (DISs) using dental imaging. In this systematic review and meta-analysis, we explored the MEDLINE/PubMed, Scopus, Embase, and Google Scholar databases and identified studies published between January 2011 and March 2022. Studies conducted on DL approaches for DIS identification or classification were included, and the accuracy of the DL models was evaluated using panoramic and periapical radiographic images. The quality of the selected studies was assessed using QUADAS-2. This review was registered with PROSPERO (CRDCRD42022309624). From 1,293 identified records, 9 studies were included in this systematic review and meta-analysis. The DL-based implant classification accuracy was no less than 70.75% (95% confidence interval [CI], 65.6%-75.9%) and no higher than 98.19 (95% CI, 97.8%-98.5%). The weighted accuracy was calculated, and the pooled sample size was 46,645, with an overall accuracy of 92.16% (95% CI, 90.8%-93.5%). The risk of bias and applicability concerns were judged as high for most studies, mainly regarding data selection and reference standards. DL models showed high accuracy in identifying and classifying DISs using panoramic and periapical radiographic images. Therefore, DL models are promising prospects for use as decision aids and decision-making tools; however, there are limitations with respect to their application in actual clinical practice.

• Structural Engineering and Mechanics
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• 제90권4호
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• pp.325-343
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• 2024

Triple-tower double-cable suspension bridges have increased confinement stiffness imposed by the main cable on the middle tower, which has bright application prospects. However, vertical bending and torsional vibrations of the double-cable and the girder are coupled in such bridges due to the hangers. In particular, the bending vibration of the towers in the longitudinal direction and torsional vibrations about the vertical axis influence the vertical bending and torsional vibrations of the stiffening girders, respectively. The conventional analytical algorithm for assessing the dynamic features of the suspension bridge is not directly applicable to this type of bridge. This study attempts to mitigate this problem by introducing an analytical algorithm for solving the triple-tower double-cable suspension bridge's natural frequencies and mode shapes. D'Alembert's principle is employed to construct the differential equations of the vertical bending and torsional vibrations of the stiffening girder continuum in each span. Vibrations of stiffening girders in each span are interrelated via the vibrations of the main cables and the bridge towers. On this basis, the natural frequencies and mode shapes are derived by separating variables. The proposed algorithm is then applied to an engineering example. The natural frequencies and mode shapes of vertical bending and torsional vibrations derived by the analytical algorithm agreed well with calculations via the finite element method. The fundamental frequency of vertical bending and first- and second-order torsion frequencies of double-cable suspension bridges are much higher than those of single-cable suspension bridges. The analytical algorithm has high computational efficiency and calculation accuracy, which can provide a reference for selecting appropriate structural parameters to meet the requirements of dynamics during the preliminary design.

• Journal of Plant Biotechnology
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• 제42권4호
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• pp.342-349
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• 2015

키위는 세계적으로 1970년대 이후 상업화되어 최근 재배가 급속히 확대되고 있는 신종 과수이며, 국내에서도 재배와 소비량이 급격히 증가하고 있다. 키위는 자웅이주 낙엽성 덩굴 식물로 과피에 털이 있고 과육색이 다양한 특성을 가지고 있으며 배수성도 다양하나, 산업적인 품종 구성은 매우 단순하다. 독특한 식물적 특성에 기인한 진화 및 생물학적 관점은 물론 다양한 품종의 효율적 개발의 요구에 따라 최근 유전체 해석 및 활용 연구가 활발히 진행되고 있다. 키위 유전체 draft 서열과 엽록체 서열이 Illumina HiSeq 기반으로 각각 2013년과 2015년에 해독 되었으며 gene annotation 연구가 계속적으로 진행되고 있다. 과거 ESTs 기반의 전사체 분석에서 최근 RNA-seq 기반의 전사체 분석으로 전환되어 과일의 아스코르브산 생합성, 과육색 발현 및 성숙, 그리고 나무의 궤양병 저항성 관련 유전적 발현조절과 유전자 발굴 연구가 중점적으로 진행되고 있다. 전통육종의 효율을 증대하기 위한 분자표지 개발 및 유전자지도 작성에 있어서는 이전의 RFLP, RAPD, AFLP 기반의 연구에서 벗어나 NGS 기반의 유전체 및 전사체 정보의 해독에 의한 SSR 및 SNP 기반의 농업적으로 중요한 형질연관 분자마커 개발 및 고밀도 유전자지도 작성이 연구되고 있다. 그러나 국내 연구는 아직 제한적인 수준에서 진행되고 있다. 향후 키위 유전체 및 전사체 분석 연구는 가까운 장래에 실질적으로 분자육종에 적용될 것으로 전망된다.

• Interdisciplinary Bio Central
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• 제4권3호
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• pp.10.1-10.12
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• 2012

Introduction: We investigated frameshift suppressor tRNAs previously reported to use five-base anticodon-codon interactions in order to provide a collection of frameshift suppressor tRNAs to the synthetic biology community and to develop modular frameshift suppressor logic devices for use in synthetic biology applications. Results and Discussion: We adapted eleven previously described frameshift suppressor tRNAs to the BioBrick cloning format, and built three genetic logic circuits to detect frameshift suppression. The three circuits employed three different mechanisms: direct frameshift suppression of reporter gene mutations, frameshift suppression leading to positive feedback via quorum sensing, and enzymatic amplification of frameshift suppression signals. In the course of testing frameshift suppressor logic, we uncovered unexpected behavior in the frameshift suppressor tRNAs. The results led us to posit a four-base binding hypothesis for the frameshift suppressor tRNA interactions with mRNA as an alternative to the published five-base binding model. Conclusion and Prospects: The published five-base anticodon/codon rule explained only 17 of the 58 frameshift suppression experiments we conducted. Our deduced four-base binding rule successfully explained 56 out of our 58 frameshift suppression results. In the process of applying biological knowledge about frameshift suppressor tRNAs to the engineering application of frameshift suppressor logic, we discovered new biological knowledge. This knowledge leads to a redesign of the original engineering application and encourages new ones. Our study reinforces the concept that synthetic biology is often a winding path from science to engineering and back again; scientific investigations spark engineering applications, the implementation of which suggests new scientific investigations.

• 한국교육학연구
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• 제24권1호
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• pp.227-254
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• 2018

본 연구는 특성화고 미래인재전형과 평가기준에 대한 입학사정교사와 지원학생의 인식차이를 살 펴보고 미래인재전형의 학생선발과 평가방향에서 고려할 시사점을 탐구하기 위해 서울특별시교 육청 산하 특성화고 미래인재전형 입학사정교사와 특성화고 1학년생을 대상으로 실시한 미래인 재전형에 관한 실태조사를 분석하였으며. 그 결과를 요약하면 다음과 같다. 첫째, 미래인재전형 제도에 관한 인식의 측면에서 교사들은 그 선발 의도에 대해 공감하면서도 성적블라인드와 전형 방법에 부정적 평가를 하였으나 미래인재전형으로 입학한 학생들의 만족도는 상대적으로 높았다. 둘째, 평가요소의 영향력 측면에서 교사들은 면접과 출석을 가장 중시하며 학업계획서 자기소개서 봉사활동 포트폴리오 순으로 고려하였으나, 학생들은 출석 면접 자기소개서 포트폴리오 학 업계획서 봉사활동 순으로 중시하여 자기소개서와 포트폴리오의 영향력을 높게 인식하였다. 셋째, 학생의 지원사유와 교사의 선발기준 측면에서 학생은 꿈 끼 취업가능성을 중시하였고 교사는 인성과 역량을 중시하였다. 이와 같은 몇 가지 측면의 결과로 볼 때, 선발자인 입학사정교사보다는 지원학생들이 미래인재전형의 선발의도에 상대적으로 부응하고 있는 것으로 나타났다. 미래인 재전형이 설립취지에 부합하기 위해서는 특성화고 별로 원하는 인재상의 정립과 지원학생들과의 전형에 관한 인식의 폭을 줄일 수 있는 평가방향을 정하고, 그에 맞는 평가기준과 선발 전략을 세워, 시대의 요구에 부합하는 인재양성의 기틀을 마련할 필요가 있다.

• 한국보건간호학회지
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• 제4권2호
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• pp.35-57
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• 1990

This study was conducted to provide information useful in developing a nursing curriculum. The sample consisted of 158 nursing students in Hanyang University and 34 faculty members who has taught them in their college & the practical area. Data were collected by using a structured questionnaire, which consisted of general characteristics of the students & their self-concept, teacher's perception of student's professional roles. The results are summarized as follows; 1. General characteristics of the students When the students applied for the university, they decided what they would specialized in. Because the motive of application for their major was simply based on their high school records, they were admitted to their university without previous knowledge of their major. The reason why they wanted to tranfer to another course after the admission was the same as above. The level of satisfaction of their major was the highest in Freshman, but in other grades the higher the;, grades were, the more they satisfied with their major and they had a better prospects about their speciality. 2. Self-concept in profermance for their major Self-concept in horne aspects was more positive perception than in social aspects & self control aspects. It resulted from tile fact that all students were females and the nursing uniqueness was based on the spirit of humanity & service. The students who had graduated from the high school in rural area wanted to tranfer to another course and taken counsel their personal problems with their parents had higher self-concept in horne aspects. As their grades were higher, the self-concept in social aspects bacame higher. The students who were satisfied with their major and took counsel their personal problems with their parents had more positive self - concept in social aspects. Self-concept in self control aspects was lower than other aspects. The students who didn't take counsel their problems with their parents, were burdened with their educational expenses and their curriculum had more negative self-concept in self control aspects. Therefore the university should be concerned about student's welfare and provide detailed orientation about their curriculum. 3. Teacher's perception about learner's professional role The role model of democratic group leader, role models for learners facilitator in a students' reach for knowledge and teaching based on soundly researched theory showed more positive perception than other factors. Their mean values were over 4. 32. The professionalism of allnurshing area, reinforcement with reinforcement for learning, nursing as part of the meaningful context of the whole showed nagative perception. Their mean values were below 3. 00. Therefore the nurse as a teacher should try to promote the locus of nursing profession and participate in their research actively.

• 한국실내디자인학회논문집
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• 제20권3호
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• pp.172-181
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• 2011

Many of penthouse apartments began to be built and distributed in Korea from the 2000s. However, we have a transformed definition from the international concept of penthouse. It seems that the penthouse apartments in Korea have a confined definition as a luxury and privileged house-we often find it out from advertisements of newly built apartments. In this thesis, therefore, it needs to make a clear and substantial definition of penthouse. And on the base of this definition, this study is intended to analyze planes of penthouse apartments which are distributed recently. It is in order to find out positive aspects of penthouse apartments and to make practical application of this analysis. The process of this study for plane-planning is as follows. Firstly, it is investigated and analyzed that external factors that have an effect on plane-planning such as locations and types of penthouse apartments. Secondly, an interior of penthouse apartments are divided into a private, public and outward area. And properties of each area through this research show the way of division and arrangement of plane. Thirdly, methods of connection between spaces is analyzed on the base of results of research for the way of partition. Finally, specific characters of penthouse apartments planning is derived from synthesis of research. In conclusion, analysis of plane-planning of penthouse apartments is summarized as follows. The majority of penthouse apartments is arranged to small portions of households and on higher stories in apartment which is situated around Han River or public parks. These external factors influence the plane-planning in both the interior and exterior way. For the exterior planning in space, it becomes important to design bays as many as possible in contact with outside in order to satisfy demands for fine prospects. It is also important to plan extra places naturally such as a terrace in order to provide virtual grounding. In the interior planning, a large size of interior induces to develop space for linking between each area, such as corridors or extra rooms. This makes it possible that the private area is linked to each other, at the same time it has its own distinctiveness according to its usage.

• 한국결정성장학회지
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• 제22권5호
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• pp.233-240
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• 2012

백색 발광다이오드(white light-emitting diodes)를 이용한 광소자는 소비전력이 상대적으로 작고, 안정적이며, 수은과 같은 유해 중금속을 포함하지 않기 때문에, 에너지 절약 및 친환경 산업측면에서 유망한 산업으로 급속히 발전하고 있다. 국내의 경우 LED 조명의 효율, 신뢰성, 연색성을 향상시키는데 필수 소재인 형광체의 기술 확보에 대한 관심이 높아지고 있다. 이러한 관점에서 기존의 YAG, TAG, silicate 계열 산화물 형광체 뿐만 아니라 고온특성이 우수한 산/질화물계 형광체 개발에 대한 관심이 높아지고 있다. 특히 산/질화물계 형광체 조성에서 $M_2Si_5N_8$ : $Eu^{2+}$, $MAlSiN_3$ : $Eu^{2+}$ M-SiON(M = Ca, Sr, Ba), ${\alpha}/{\beta}$-SiAlON : $Eu^{2+}$과 같은 재료는 440~460 nm 영역에서의 넓은 여기파장과 우수한 발광효율로 청색 LED 칩을 이용한 백색 LED에 넓게 사용되고 있다. 이 논문에서는 이러한 산/질화물계 형광체 조성의 결정학적, 광학적 특성 및 응용에 대해서 정리하였다. 또한 최근에 주목받고 있는 양자점(quantum dots) 형광체를 응용한 white LEDs의 개발동향에 대해서도 알아보도록 한다.