• Title/Summary/Keyword: article 25

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Inorganic charge transport materials for high reliable perovskite solar cells (고신뢰성 페로브스카이트 태양전지용 무기물 기반 전하전달층)

  • Park, So Jeong;Ji, Su Geun;Kim, Jin Young
    • Ceramist
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    • v.23 no.2
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    • pp.145-165
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    • 2020
  • Halide perovskites are promising photovoltaic materials due to their excellent optoelectronic properties like high absorption coefficient, low exciton binding energy and long diffusion length, and single-junction solar cells consisting of them have shown a high certified efficiency of 25.2%. Despite of high efficiency, perovskite photovoltaics show poor stability under actual operational condition, which is the mostly critical obstacle for commercialization. Given that the stability of the perovskite devices is significantly affected by charge-transporting layers, the use of inorganic charge-transporting layers with better intrinsic stability than the organic counterparts must be beneficial to the enhanced device reliability. In this review article, we summarized a number of studies on the inorganic charge-transporting layers of the perovskite solar cells, especially focusing on their effects on the enhanced device reliability.

Two-Dimensional Finite Element Analysis of Bone Resorption from the Artificial Hip Replacement (인공고관절 골흡수로 인한 응력분포 변화의 2차원 유한요소 해석)

  • Choi, Hyung-Yeon;Chae, Soo-Won;Kim, Sung-Kon
    • Journal of Biomedical Engineering Research
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    • v.16 no.1
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    • pp.25-32
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    • 1995
  • Clinically, proximal bone resorption in the femur is frequently seen postoperatively on the follow up XI-rays after total hip replacement (THR). We developed the finite element model of cementless THR. The model is two dimensional side plate model, whereby the three dimensional structural integrity of the bone can be accounted for by a separate two dimensional mesh, a side plate. The subject of this article is the development and application of this two dimensional side plate FEM to study the reverse effect of the various degree of bone resorption of femur after THR. The results of this study indicates that 1) two dimensional side plate model is good and simple alternative to complex three dimensional model and 2) the severity of the proximal bone resorption has the effect of more increasing stress on the cortex at the level of femoral stem tip.

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A Study on the Experience of Designing Community Problem Solving Education based on the Undergraduate-Graduate Class Linkage (학부-대학원 연계 지역문제해결형 수업설계 경험에 관한 연구)

  • Han, Kyonghee
    • Journal of Engineering Education Research
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    • v.23 no.5
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    • pp.16-25
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    • 2020
  • This article aims to analyze the experience of designing and operating a class model linking undergraduate and graduate students in engineering education and suggest its development direction. To achieve these objectives, the undergraduate-graduate linked class model was applied to community problem-solving education and a case was analyzed. It also specifically presented the process of how we design the class model and what the actual operational performances and improvements are. This study found that undergraduate and graduate students could build integrated and horizontal cooperative relationships in their classes through undergraduate-graduate linked education and, particularly, graduate students could gain meaningful educational experiences. However, it was difficult to obtain tangible performances through the team activities of these students within a semester. In order for engineering colleges to operate undergraduate-graduate linked education, it would be necessary to provide a longer and more systematic educational environment and better curriculum. The study tried to seek specific tasks and ways to improve them.

Assessment in Outcome-Based Education (성과중심교육에서 학생평가)

  • Im, Sun Ju
    • Korean Medical Education Review
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    • v.15 no.1
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    • pp.25-30
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    • 2013
  • Assessment plays a vital role in outcome-based education (OBE). This article describes the characteristics of assessment and appropriate assessment instruments for measuring learning outcomes in OBE. Assessment in OBE needs to be formative, continuous, and frequent. Miller's pyramid is useful for selecting the appropriate assessment instruments to reflect a specific outcome; different methods can be applied to evaluate one outcome. Outcomes and competency mean that student must 'do'; therefore, performance tests are emphasized. Qualitative methods as well as quantitative methods are used to evaluate the outcomes of areas such as professionalism or ethics. An absolute criterion-based standard is usually applied to decide whether students pass or fail, but the decision should be based on gathering value judgments and reaching consensus. Active participation of faculty members and students in assessment is crucial.

A Study of Names Used on Seals in the Age of Civil Wars in China (중국전국시대 인장(印章)에 반영된 인명 특징 연구)

  • Moon, Byung-soon
    • Cross-Cultural Studies
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    • v.19
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    • pp.25-38
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    • 2010
  • The "Name" is not only representative of a person but also a cultural heritage containing national cultures. Therefore, we can easily find some cultural value from the square inch sized seal texts. This article is a comprehensive study of the characteristics of names appeared on the seals in the Warring States Period. In the Warring States Period, single name is generally used for naming and this style can be divided into 13 categories. Except unavoidable cases, such as using the name of place, the name of person or the reason of physical characteristics, using double name is very rare and this style can be categorized by 8 kinds. In result, using double name is defined as a fringe method of naming in the Warring States Period. In addition, we can find a big difference between the names of Warring States Period and those of Post-Qin and Han Dynasties in the structural aspects. In conclusion, understanding of the characteristics of names from the Warring States Period can be a great help to better understanding of ancient books and unearthed documents.

Assessment of Right Ventricular Function in Pulmonary Hypertension with Multimodality Imaging

  • Seo, Hye Sun;Lee, Heon
    • Journal of Cardiovascular Imaging
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    • v.26 no.4
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    • pp.189-200
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    • 2018
  • Pulmonary hypertension (PH) is defined as resting mean pulmonary artery pressure ${\geq}25mmHg$ and is caused by multiple etiologies including heart, lung or other systemic diseases. Evaluation of right ventricular (RV) function in PH is very important to plan treatment and determine prognosis. However, quantification of volume and function of the RV remains difficult due to complicated RV geometry. A number of imaging tools has been utilized to diagnose PH and assess RV function. Each imaging technique including conventional echocardiography, three-dimensional echocardiography, strain echocardiography, computed tomography and cardiac magnetic resonance imaging has-advantages and limitations and can provide unique information. In this article, we provide a comprehensive review of the utility, advantages and shortcomings of the multimodality imaging used to evaluate patients with PH.

Examining the Effects of Job Roles in Small and Medium Business Corporation on Smart Manufacturing Employee Training (스마트제조 인력양성에 대한 제언 : 중소제조기업 구성원의 특성을 중심으로)

  • Park, Sangwoo;Lee, Jongkil;Jung, Dongyul
    • Journal of Information Technology Services
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    • v.20 no.3
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    • pp.13-25
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    • 2021
  • The article presents the results of how employee's hierarchical job roles differently recognize a SM(smart manufacturing) and evaluate comprehensively on the SM employees training. The research was focus on small and medium size manufacturing corporation in Banwol·Siwha industrial complex, where is carried out Smart Complex National Policy. The Results from 205 participants working for a manufacturing firms in the Banwol·Siwha industrial complex. The results of study show that managers (vs workers) group is higher recognition of smart manufacturing and more intention to participate a SM employee training and utilize a SM equipments for test a manufacturing process. and these variables were mediated by SM cognition. These results will help SM manpower training center strategically design their training programs to maximize the training effectiveness.

Mindfulness-Based Therapy for Insomnia (마음챙김명상과 불면증)

  • Lee, Hwa-Young
    • Sleep Medicine and Psychophysiology
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    • v.28 no.1
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    • pp.13-17
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    • 2021
  • Sleep disturbance is a common health complaint affecting an estimated 10-25% of the general population. Pharmacotherapy is a traditional treatment and cognitive behavioral therapy is well demonstrated as an efficacious treatment for insomnia. There is a growing interest in the effectiveness of mindfulness meditation for sleep disturbed populations. Mindfulness involves focused, purposeful, nonjudgmental attention to a particular idea. In clinical application of mindfulness practice, mindfulness-based stress reduction and mindfulness-based cognitive therapy are used widely. Clinical trials support the effectiveness of meditation for the treatment of insomnia. The aim of this article is to review the effect of mindfulness meditation on insomnia.

Theoretical Aspects of Blockchain Technologies in The Sphere of Education

  • Liashkevych, Antonina;Babyshena, Mariana;Vorokhaev, Oleksandr;Pylypiv, Volodymyr;Oliinyk, Oksana;Kinakh, Nelia
    • International Journal of Computer Science & Network Security
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    • v.21 no.3
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    • pp.185-190
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    • 2021
  • The article provides a literary and analytical review in the following areas of search: problems and prerequisites for changes in the field of education, innovations and innovative models in education, the use of new technologies in teaching. A proposal for a business plan and accompanying documentation for a new methodology based on blockchain technologies were developed, to assess the economic efficiency of the project. The main systems of the new model were modeled on the basis of the proposed methodology, to develop a prototype based on the project documentation.

Pathogenesis, evaluation, and management of osteolysis after total shoulder arthroplasty

  • Kunze, Kyle N.;Krivicich, Laura M.;Brusalis, Christopher;Taylor, Samuel A.;Gulotta, Lawrence V.;Dines, Joshua S.;Fu, Michael C.
    • Clinics in Shoulder and Elbow
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    • v.25 no.3
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    • pp.244-254
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    • 2022
  • Radiographic osteolysis after total shoulder arthroplasty (TSA) remains a challenging clinical entity, as it may not initially manifest clinically apparent symptoms but can lead to clinically important complications, such as aseptic loosening. A thorough consideration of medical history and physical examination is essential to rule out other causes of symptomatic TSA-namely, periprosthetic joint infection-as symptoms often progress to vague pain or discomfort due to subtle component loosening. Once confirmed, nonoperative treatment of osteolysis should first be pursued given the potential to avoid surgery-associated risks. If needed, the current surgical options include glenoid polyethylene revision and conversion to reverse shoulder arthroplasty. The current article provides a comprehensive review of the evaluation and management of osteolysis after TSA through an evidence-based discussion of current concepts.