• Journal of Korean Neurosurgical Society
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• 제62권1호
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• pp.10-26
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• 2019

Magnetic resonance-guided focused ultrasound (MRgFUS) is an emerging new technology with considerable potential to treat various neurological diseases. With refinement of ultrasound transducer technology and integration with magnetic resonance imaging guidance, transcranial sonication of precise cerebral targets has become a therapeutic option. Intensity is a key determinant of ultrasound effects. High-intensity focused ultrasound can produce targeted lesions via thermal ablation of tissue. MRgFUS-mediated stereotactic ablation is non-invasive, incision-free, and confers immediate therapeutic effects. Since the US Food and Drug Administration approval of MRgFUS in 2016 for unilateral thalamotomy in medication-refractory essential tremor, studies on novel indications such as Parkinson's disease, psychiatric disease, and brain tumors are underway. MRgFUS is also used in the context of blood-brain barrier (BBB) opening at low intensities, in combination with intravenously-administered microbubbles. Preclinical studies show that MRgFUS-mediated BBB opening safely enhances the delivery of targeted chemotherapeutic agents to the brain and improves tumor control as well as survival. In addition, BBB opening has been shown to activate the innate immune system in animal models of Alzheimer's disease. Amyloid plaque clearance and promotion of neurogenesis in these studies suggest that MRgFUS-mediated BBB opening may be a new paradigm for neurodegenerative disease treatment in the future. Here, we review the current status of preclinical and clinical trials of MRgFUS-mediated thermal ablation and BBB opening, described their mechanisms of action, and discuss future prospects.

• 한국콘텐츠학회논문지
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• 제21권5호
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• pp.349-358
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• 2021

본 연구의 목적은 코로나 19로 인하여 원격수업을 하고 있는 자녀들이 해결중심상담을 통하여 게임시간, 부모 자녀 간의 의사소통, 미래에 대한 계획 등이 어떻게 변화될 수 있는지를 살펴보고자 하였다. 연구참여자는 세 명의 자녀들과 어머니이다. 세 명의 자녀들은 초등학생이고, 원격수업을 하고 있었다. 본 연구에서는 해결중심상담의 상담기법을 활용하였다. 자료분석은 Creswell의 나선형 자료 분석 방법을 활용하였다. 본 연구의 결과는 다음과 같다. 첫째, 원격수업을 하는 자녀들은 해결중심상담을 통하여 게임시간이 감소하였다. 둘째, 원격수업을 하는 자녀들은 해결중심상담을 통하여 부모 자녀 간의 의사소통에 긍정적인 변화가 나타났다. 셋째, 원격수업을 하는 자녀들은 해결중심상담을 통하여 자신의 미래를 계획할 수 있는 계기가 되었다.

• 대한의용생체공학회:의공학회지
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• 제43권6호
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• pp.369-374
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• 2022

Purpose: Focused ultrasound is an emerging technology for treating the brain locally in a noninvasive manner. In this study, we have investigated the influence of skull properties on simulating transcranial pressure field. Methods: A 3D computational model of transcranial focused ultrasound was constructed using female and male CT data to solve for intracranial pressure. For heterogeneous model, the acoustic properties were calculated from CT Hounsfield units based on a porosity. The homogeneous model assigned constant acoustic properties for the single-layered skull. Results: A computational model was validated against empirical data. The homogeneous models were then compared with the heterogeneous model, resulted in 10.87% and 7.19% differences in peak pressure for female and male models respectively. For the focal volume, homogeneous model demonstrated more than 94% overlap compared with the heterogeneous model. Conclusion: Homogeneous model can be constructed using MR images that are commonly used for the segmentation of the skull. We propose the possibility of the homogeneous model for the simulating transcranial pressure field owing to comparable focal volume between homogeneous model and heterogeneous model.

• 한국초전도ㆍ저온공학회논문지
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• 제8권1호
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• pp.19-22
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• 2006

Desirable substrates for $YBa_2Cu_3O_{7-\delta}$ coated conductor are highly cube textured Ni or Ni-alloy tapes, which can be produced by cold rolling and recrystallization annealing. We have fabricated hi-axially textured pure Ni tapes for the application of coated conductors. The sintered Ni rod was cold-rolled into the thin tapes of $50{\mu}m$ thickness and the tapes were heat-treated for texture development with line-focused infrared heater. The temperature was maintained at $800\sim1050^{\circ}C$, using 1kW double ended linear halogen lamp in $96%Ar-4%H_2$ atmosphere The biaxially tortured Ni tapes were successfully formed by line-focused infrared heat treatment The texture of the annealed Ni tapes was analysed using the GADDS (general area detector diffraction system). The full width at half maximum values of phi and omega scan for the Ni tapes were less than $10^{\circ}$ and the grain size was $20-50{\mu}m$.

• 한국음향학회지
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• 제39권6호
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• pp.576-584
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• 2020

폴리비닐알코올(polyvinyl alcohol, PVA)젤을 온도가시화용 생체모의매질로 사용하기 위한 기초적인 정보를 얻기 위하여, PVA의 농도를 바꾸어가며 집속초음파에 의한 온도변화 특성을 조사하였다. 기본적인 음향 특성을 조사하기 위하여 PVA농도에 따른 음속, 감쇠계수, 밀도 등이 측정되었고 열역학적 특성인 열전도도, 열용량이 측정되었다. 30 ℃ 이상에서 변색되는 시온필름을 사용하여 집속초음파에 의해 상승되는 초점부근의 온도 변화의 범위를 관찰하였으며 기록된 이미지의 화상처리를 통하여 변색범위의 면적을 도출하였다. PVA의 농도가 2 wt%~16 wt%의 범위에서 증가할수록 젤 내부에서 30 ℃ 이상으로 상승하는 영역은 선형적으로 증가함을 보였고 집속초음파 트랜스 듀서에 인가하는 파워가 증가할수록 변색영역이 증가함을 확인하였다. 이들 결과는 유한요소법을 사용한 시뮬레이션 결과와도 좋은 일치를 보였다.

• 복식
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• 제66권3호
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• pp.147-161
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• 2016

This study analyzed the effects of job style on job satisfaction and turnover intention of fashion models, and the difference in the job style, job satisfaction and turnover intention by model activities period. Data was collected by surveying fashion models with more than 10 modeling experiences, and 230 responses were used in the data analysis. The results of were as follows: First, the job style of fashion models were classified into professional ability type, social relationship-focused type, future-oriented type and body-boasting type. Job satisfaction was classified into satisfaction with working conditions, satisfaction with model activities, and satisfaction with relationships. Turnover intention was classified into intention to change jobs, and intention to quit modeling. Second, being a professional ability type had a negative effect on satisfaction with working conditions, whereas being a future-oriented type had a positive effect on it. The professional ability type and social relationship-focused type had a positive effect on satisfaction with model activities, and the social relationship-focused type had a positive effect on satisfaction with relationships. Third, the future-oriented type and body-boasting type had a negative effect on the intention to change jobs. The social relationship-focused type, future-oriented type and body-boasting type had a negative effect on the intention to quit modeling. Fourth, there were significant differences in the professional ability type, human relationship-focused type, body-boasting type, intention to change jobs and intention to quit modeling by model activities period. Therefore, it is necessary for domestic fashion models to have the appropriate attitude to develop features and competency required for modeling projects and if improvements are made to enhance job satisfaction of fashion models, the fashion modeling industry is expected to make further developments.

• 정보처리학회논문지B
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• 제12B권6호
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• pp.697-702
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• 2005

주제 중심 웹 문서 수집기는 검색엔진에서 최신의 웹 문서 색인을 유지하는 대안방안으로 부상하고 있다. 그러나 주제 중심 웹 문서 수집기는 비 관심문서에서 연결된 관심문서들을 수집할 수 없는 문제점을 가지고 있다. 이러한 문제점은 문서의 구조적 특징을 고려하지 않아서 발생한다. 특히 문서분석 방법인 문서의 발생 횟수 및 역문헌 발생빈도는 이러한 문제를 야기하는 주요 원인이 된다 주제 중심 웹 문서 수집기의 성능을 향상하기 위해서 본 논문에서는 국소 정보기반의 문서 분할법을 제안한다. 본 논문에서는 문서를 하이퍼링크 주변의 문맥을 고려한 특징 정보들을 사용하여 여러 소각의 문서로 나눈다. 본 논문에서 제안하는 주제 중심 웹 문서 수집기는 나누어진 문서들을 이용하여 하이퍼링크가 관심문서를 가리키는 것인지를 판단하여 문서를 수집할 것인지를 판단한다.

• 한국콘텐츠학회논문지
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• 제14권11호
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• pp.476-485
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• 2014

본 연구에서는 초등학생을 위한 해결중심 집단상담프로그램의 효과크기를 통합하여 제시하고, 보다 효과적인 해결중심 집단상담프로그램에 대한 실천적 방안을 제시하기 위하여 메타분석을 실시하였다. 자료 수집은 2014년 5월까지 국내에서 발표된 석 박사 학위논문 및 학술지에 게재된 논문 중 메타분석의 대상선정기준에 따라 논문을 선정하여 분석하였다. 메타분석을 위해서는 CMA(Comprehensive Meta-Analysis) software 2.0을 사용하였으며, 연구의 주요 결과는 다음과 같다. 첫째, 초등학생을 대상으로 국내에서 실시된 해결중심 집단상담프로그램의 평균효과크기를 살펴보면, 자아존중감의 효과크기가 1.61으로 가장 높게 나타났고, 학교적응능력이 1.35, 대인관계능력이 1.07, 자기효능감이 1.03 의 순으로 나타나서 네 가지 변수 모두 큰 효과크기를 보였다. 둘째, 해결중심 집단상담프로그램의 효과크기가 조절변수에 따라 어떻게 차이가 나는지 살펴보았다. 통계적으로 유의미한 조절변수는 자아존중감의 경우에 '총회기수'이었고 학교적응능력의 경우에는 '총회기수'와 '1회기당 시간'으로 나타났다. 본 연구결과를 바탕으로 초등학생을 위한 해결중심 집단상담프로그램의 실천적 함의와 전략을 제언하였다.

• 한국경영과학회지
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• 제38권1호
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• pp.103-121
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• 2013

Since American Airlines's mileage program emerged in market, loyalty programs have gained popularity. Many companies have generated many kinds of reward cards in order to induce precious consumers. As a result, reward cards are very important in consumer goods market and become diversified. In spite of its importance, little is known about how these cards influence consumer's perception. The prior research has not focused on reward card types and psychological variables. Accordingly this research intends to investigate psychological variables such as transaction coupling and sunk cost perception. According to the theory of regulatory focus, promotion focus consumers would point to gain-nongain frame work, but prevention focus consumers would point to loss-nonloss frame work. The paper proved the effect of reward card types and regulatory focus on transaction coupling and sunk cost perception. Based on the results from 2(type of card : visible vs invisible) ${\times}$ 2(regulatory focus: promotion vs prevention) between-subjects factorial design experiments, we found that consumer's transaction coupling and sunk cost perception of visible reward card are better recognized than invisible reward card. In addition, the results show that there is a significant interaction effect between the type of reward card and regulatory focus. Specifically promotion focused consumers tend to reveal better perception than prevention focused consumers in use of invisible cards. However, prevention focused consumers tend to show better perception than promotion focused consumers in use of visible cards. These findings will contribute to significant academic development and practically useful help to marketing managers.

• 음성과학
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• 제9권4호
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• pp.187-200
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• 2002

The purpose of the present study is to see in terms of $F_{0}$ variation in Japanese how discourse focus and the lexical word accent interact with each other in realizing overall intonation patterns. Discourse focus causes prosodic restructuring of phrase structures and, as a result, largely affects pitch contours, whereas the lexical word accent is said to delimit the $F_{0}$ into a certain range. Measurement of $F_{0}$ was made of utterances of Japanese sentences to observe behavior of pitch contours with varied focus assignment and lexical accent specifications. The utterances were obtained in question-answer discourse contexts so that in a sentence, either one NP was always focused or no focus was assigned. I set four points for $F_{0}$ measurement; $F_{1s},F_{1m}, F_{2s}$, and $F_{2m}$, two for each noun phrase corresponding to $F_{0}$ at the beginning of the first syllable and that of the vocalic portion of the second syllable in the two NP's. The results of present study were as follows: (1) for all combination of lexical accent types, the $F_{0}$ rise both in NP1 and NP2 are higher when focused than when not focused. (2) NP2 starts a new accentual phrase when focused, showing even higher $F_{0}$ than NP1, the latter of which implies that in forming a new accentual phrase by focusing, catathesis does not seem to take effect on NP2 preceded by accented NP1. (3) unfocused NP2 preceded by unaccented NP1 has higher $F_{0}$ than those preceded by accented NP1.