• 디지털융복합연구
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• 제20권1호
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• pp.191-202
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• 2022

본 연구의 목적은 고등학교 남자 축구선수 24명을 대상으로 10주간 신체안정화운동 프로그램 중재 후 기술체력에 미치는 영향을 규명하는 것이다. 블레이즈포드로 시각반응속도 검사를 시행한 결과 위팔, 왼발, 오른발의 15초간 반응횟수와 반응시간(p<0.001)은 유의하게 증가하였다. 기능적 움직임 평가하기 위해 7가지 동작의 향상 여부 평가결과 허들건너기(p<0.001), 능동적폄다리올리기(p=0.022) 동작이 유의하게 향상되었다. 균형능력을 평가하기 위해 와이발런스 평가결과 양쪽 복합점수(p<0.001)가 유의하게 향상하였다. 기동력과 근지구력을 평가하기 위해 폐활량 측정결과 노력성폐활량(p<0.001)과 1초간 강제날숨량(p=0.003)이 유의하게 향상되었다. 10주간 신체안정화운동 중재 후, 경기에 필요한 기술 체력인 순발력, 민첩성, 다리 근력, 다리의 안정성, 기동력, 근지구력을 효과적으로 향상할 수 있다는 결론을 얻었고, 이러한 기술체력의 향상은 축구선수들의 부상을 방지할 수 있으며, 경기력을 향상할 수 있을 것이다.

• 한국전산구조공학회논문집
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• 제36권5호
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• pp.323-330
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• 2023

PVA 섬유 보강 시멘트 복합체는 매우 복잡한 미세구조를 가지고 있으며, 재료의 거동을 정확히 평가하기 위해서는 미세구조 특성을 반영하여 실제 실험과 시너지효과를 내며 효율적인 재료 설계를 가능하게 하는 해석 모델의 개발이 중요하다. PVA 섬유 보강 시멘트 복합체의 역학적 성능은 PVA 섬유의 방향성에 큰 영향을 받는다. 그러나 마이크로-CT 이미지로부터 얻은 PVA 섬유의 회색조 값을 인접한 상과 구분하기 어려워, 섬유 분리 과정에 많은 시간이 소요된다. 본 연구에서는 섬유의 3차원 분포를 얻기 위하여 0.65㎛³의 복셀 크기를 가지는 마이크로-CT 이미지 촬영을 수행하였다. 학습에 사용될 학습 데이터를 생성하기 위해 히스토그램, 형상, 그리고 구배 기반 상 분리 방법을 적용하였다. 본 연구에서 제안된 U-net 모델을 활용하여 PVA 섬유 보강 시멘트 복합체의 마이크로- CT 이미지로부터 섬유를 분리하는 학습을 수행하였다. 훈련의 정확도를 높이기 위해 데이터 증강을 적용하였으며, 총 1024개의 이미지를 훈련 데이터로 사용하였다. 모델의 성능은 정확도, 정밀도, 재현율, F1 스코어를 평가하였으며, 학습된 모델의 섬유 분리 성능이 매우 높고 효율적이며, 다른 시편에도 적용될 수 있음을 확인하였다.

• 동의생리병리학회지
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• 제38권1호
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• pp.1-9
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• 2024

Cognitive reserve (CR) is a concept that can explain the discrepancies between the pathologic burden of the disease and clinical manifestations. It refers to the individual susceptibility to age-related brain changes and pathologies related to Alzheimer's disease, thus recognized as a factor affecting the trajectories of the disease. The purpose of this study was to explore the current states of clinical studies on neural substrates of CR in Alzheimer's disease using functional magnetic resonance imaging. We searched for clinical studies on CR using fMRI in the Pubmed, Cochrane library, RISS, KISS and ScienceON on August 14, 2023. Once the online search was finished, studies were selected manually by the inclusion criteria. Finally, we analyzed the characteristics of selected articles and reviewed the neural substrates of CR. Total thirty-four studies were included in this study. As surrogate markers of CR, not only education and occupational complexity, but also composite score and questionnaire-based method, which cover various areas of life, were mainly used. The most utilized methods in resting-state fMRI were independent component analysis, seed-based analysis, and graph theory analysis. Through the analysis, we demonstrated that neuroimaging techniques could capture the neural substrates associated with cognitive reserve. Moreover, functional connectivity of brain regions centered on prefrontal and parietal cortex and network areas such as default mode network showed a significant correlation with CR, which indicated a significant association with cognitive performance. CR may induce differential effects according to the disease status. We hope that this perspective on cognitive reserve would be helpful when conducting clinical researches on the mechanisms of traditional Korean medicine for Alzheimer's disease in the future.

• Korean Circulation Journal
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• 제52권7호
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• pp.544-555
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• 2022

Background and Objectives: The outcome benefits of β-blockers in chronic coronary artery disease (CAD) have not been fully assessed. We evaluated the prognostic impact of β-blockers on patients with chronic CAD after percutaneous coronary intervention (PCI). Methods: A total of 3,075 patients with chronic CAD were included from the Grand Drug-Eluting Stent registry. We analyzed β-blocker prescriptions, including doses and types, in each patient at 3-month intervals from discharge. After propensity score matching, 1,170 pairs of patients (β-blockers vs. no β-blockers) were derived. Primary outcome was defined as a composite endpoint of all-cause death and myocardial infarction (MI). We further analyzed the outcome benefits of different doses (low-, medium-, and high-dose) and types (conventional or vasodilating) of β-blockers. Results: During a median (interquartile range) follow-up of 3.1 (3.0-3.1) years, 134 (5.7%) patients experienced primary outcome. Overall, β-blockers demonstrated no significant benefit in primary outcome (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.63-1.24), all-cause death (HR, 0.87; 95% CI, 0.60-1.25), and MI (HR, 1.25; 95% CI, 0.49-3.15). In subgroup analysis, β-blockers were associated with a lower risk of all-cause death in patients with previous MI and/or revascularization (HR, 0.38; 95% CI, 0.14-0.99) (p for interaction=0.045). No significant associations were found for the clinical outcomes with different doses and types of β-blockers. Conclusions: Overall, β-blocker therapy was not associated with better clinical outcomes in patients with chronic CAD undergoing PCI. Limited mortality benefit of β-blockers may exist for patients with previous MI and/or revascularization.

• Journal of Animal Science and Technology
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• 제48권1호
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• pp.15-20
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• 2006

국내에서 사용한 젖소 정액을 네 가지(한국형 보증종모우 정액, 농협 수입 보증종모우 정액, 미국산 수입 정액, 카나다산 수입 정액)로 분류하여 표현형 능력 및 유전능력을 비교하였다. 유전능력의 경우 농촌진흥청 축산연구소에 수행하고 있는 국가단위 젖소유전능력평가 결과를 이용하였다. 유량, 유지량 및 유단백량의 표현형 능력의 경우 미국산 수입 정액이 가장 우수하였고, 한국형 보증종모우 정액은 미국산 수입 정액과 유의한 차이를 보였다. 1991년 이후 태어난 보증종모우의 경우 유지량은 네 종류의 정액 사이에 유의한 차이가 없었다. 유량, 유지량, 유단백량, 유단백율 유전능력의 경우 네 종류 사이에 유의한 차이가 없었으며, 유지율의 경우 한국형 보증종모우 정액이 가장 우수하였다. 선형심사 최종점수 및 유방종합지수의 경우 카나다산 수입정액이 가장 우수하였으며, 한국형 보증종모우 정액과 유의한 차이를 보였다. MFP 및 KTPI의 경우 네 종류 사이에 유의한 차이가 없었다. 1991년 이후에 태어난 보증종모우의 유량 및 유단백량의 경우 네 종류 사이에 유의한 차이가 없었으나, 유지량, 유지율 및 유단백율의 경우 한국형 보증종모우 정액이 가장 우수하였고, 나머지 정액과 유의한 차이를 보였다. 선형심사 최종점수의 경우 한국형 보증종모우 정액, 미국산 수입정액 및 카나다산 수입정액 사이에 통계적으로 유의한 차이가 없었다. 유방종합지수의 경우 카나다산 수입정액이 가장 우수하였고, 한국형 보증종모우 정액과 유의한 차이가 났다. MFP의 경우 한국형 보증종모우 정액이 가장 우수하였고, 나머지 정액과 유의한 차이를 보였다. KTPI의 경우 한국형 보증종모우 정액, 미국산 수입정액 및 카나다산 수입정액 사이에 통계적으로 유의한 차이가 없었다.

• 대한핵의학회지
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• 제30권3호
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• pp.299-314
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• 1996

The purpose of the present study was to validate the use of tissue radioactivity ratios instead of regional metabolic rates for the assessment of regional metabolic changes in Alzheimer's disease(AD) with [$^{18}F$]FDG PET and to examine the correlation of ratio indices with the severity of cognitive impairment in AD. Thirty-seven AD Patients(age $68{\pm}9 yrs$, $mean{\pm}s.d.$; 36 probable and 1 definite AD), 28 patients with dementia of non-Alzheimer type(age $66{\pm}7 yrs$), and 17 healthy controls(age $66{\pm}4 yrs$) underwent [$^{18}F$]FDG PET imaging. Two simplified radioactivity ratio indices were calculated from 37-66 min image: region-to-cerebellar radioactivity ratio(RCR) and a composite radioactivity ratio(a ratio of radioactivity in the most typically affected regions over the least typically affected regions: CRR). Local cerebral metabolic rate for glucose(LCMRglu) was also measured using a three-compartment, five-parameter tracer kinetic model. The ratio indices were significantly lower in AD patients than in controls(RCR in temporoparietal cortex, $0.949{\pm}0.136$ vs. $1.238{\pm}0.129$, p=0.0004; RCR in frontal cortex, $1.027{\pm}0.128$ vs. $1.361{\pm}0.151$, p<0.0001; CRR, $0.886{\pm}0.096$ vs. $1.032{\pm}0.042$. p=0.0024). On the RCR analysis, 86% of AD patients showed a pattern of bilateral temporoparietal hypometabolism with or without frontal involvement; hypometabolism was unilateral in 11% of the patients. When bilateral temporoparietal hypometabolism was considered to be suggestive of AD, the sensitivity and specificity of the RCR analysis for the differential diagnosis of AD were 86% and 73%, respectively. The RCR was correlated significantly with the macroparameter K [$K_1k_3/(k_2+k_3)$] (r=0.775, p<0.0001) and LCMRglu(r=0.633, p=0.0002) measured using the kinetic model. In patients with AD, both average RCR of cortical association areas and CRR were correlated with Mini-Mental Status Examination(r=0.565, p=0.0145; r=0.642, p=0.0031, respectively), Clinical Dementia Rating(r=-0.576, p=0.0124; r=-0.591, p=0.0077), and total score of Mattis Dementia Rating Scale (r=0.574, p=0.0648; r=0.737, p=0.0096). There were also significant correlations between memory and language impairments and corresponding regional RCRs. The results suggest that the [$^{18}F$]FDG PET ratio indices, RCR and CRR, reflect global and regional metabolic rates and correlate with the severity of cognitive impairment in AD. The simplified ratio analysis may be clinically useful for the differential diagnosis and serial monitoring of the disease.

• 대한한의학회지
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• 제26권2호
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• pp.95-104
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• 2005

Objectives: This was a double blinded, randomized, placebo-controlled clinical study for evaluation of safety and effective dose finding of Cardiotonic Pills$^{(R)}$ in patients with chest pain and discomfort. Cardiotonic Pills$^{(R)}$ are composed of Salviae Miltiorrhizae Radix (丹蔘), Notoginseng Radix (三七根) and Borneolum (龍腦). Major effects of Salviae Miltiorrhizae Radix and Notoginseng Radix are vasodilatation, sedation and analgesic action. Borneolum has an antibacterial effect, and can stimulate the central nervous system. All of these substances are oriental herbs that have been used for a long time in east Asia. Cardiotonic Pills fi received Investigational New Drug (IND) approval from the Food and Drug Administration (FDA) in the USA and 40 million people in the world take this pill. We performed a phase IV clinical study to confirm its efficacy and safety in patients who have probable cardiogenic or psychogenic chest pain or chest stifling. Methods: This study was planned for a multi-center clinical trial including four university hospitals of oriental medicine in Korea. This was the first time to evaluate the 'planning treatment according to diagnosis (辨證施治)' of chest pain or chest discomfort according to oriental medical guidelines. The patients who were included in this trial were adult volunteers from 20 to 70 years old who had chest pain or chest discomfort more than twice during a recent month, and we received written consent to participate in this study from all of them. After administration of Cardiotonic Pills$^{(R)}$ for 8 weeks, number of occurrences, duration, appearance and degree of chest pain or chest discomfort was observed and degree of symptoms (severity of illness, global improvement) were measured using a patient's global assessment composite scale. Results: In the patient's global assessment scale, the severity of illness of the Cardiotonic Pills$^{(R)}$ group (n=25) was 14/25=0.56 but of the placebo group (n=25) was 7/25=0.28 (p-value=0.0449). This result indicates Cardiotonic Pills$^{(R)}$have a positive effect on the symptoms of chest pain and discomfort. However, the global improvement of the Cardiotonic Pills$^{(R)}$group was 23/25=0.92, and of the placebo group was 22/25=0.88 (p-value=0.6374). The total symptom score of the Cardiotonic Pills$^{(R)}$ group was $1.68\pm20.06$, and of the placebo group was $16.76\pm72.l4$(p-value=0.2285). The number of symptom events of the Cardiotonic Pills$^{(R)}$ group was $72\pm29.78$, and of the placebo group (n=25) was $10.80\pm38.42$ (p­value=0.3660). We could not find any effects on the other factors examined besides the severity of illness, beyond the difference of standard deviations. Conclusions: Cardiotonic Pills$^{(R)}$ significantly reduced chest pain and chest discomfort in patients. Therefore, we expect that Cardiotonic Pills$^{(R)}$ will be helpful for patients with chest pain and chest discomfort not only caused by heart disease but also by other diseases.

• Asia pacific journal of information systems
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• 제18권2호
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• pp.1-14
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• 2008

According to technology acceptance model(TAN) which is one of the most important research models for explaining IT users' behavior, on intention of using IT is determined by usefulness and ease of use of it. However, TAM wouldn't explain the performance of using IT while it has been considered as a very good model for prediction of the intention. Many people would not be confirmed in the performance of using IT until they can control it at their will, although they think it useful and easy to use. In other words, in addition to usefulness and ease of use as in TAM, controllability is also should be a factor to determine acceptance of IT. Especially, there is a very close relationship between controllability and ease of use, both of which explain the other sides of control over the performance of using IT, so called perceived behavioral control(PBC) in social psychology. The objective of this study is to identify the relationship between ease of use and controllability, and analyse the effects of both two beliefs over performance and intention in using IT. For this purpose, we review the issues related with PBC in information systems studies as well as social psychology, Based on a review of PBC, we suggest a research model which includes the relationship between control and performance in using IT, and prove its validity empirically. Since it was introduced as qa variable for explaining volitional control for actions in theory of planned behavior(TPB), there have been confusion about concept of PBC in spite of its important role in predicting so many kinds of actions. Some studies define PBC as self-efficacy that means actor's perception of difficulty or ease of actions, while others as controllability. However, this confusion dose not imply conceptual contradiction but a double-faced feature of PBC since the performance of actions is related with both self-efficacy and controllability. In other words, these two concepts are discriminated and correlated with each other. Therefore, PBC should be considered as a composite concept consisting of self-efficacy and controllability, Use of IT has been also one of important areas for predictions by PBC. Most of them have been studied by analysis of comparison in prediction power between TAM and TPB or modification of TAM by inclusion of PBC as another belief as like usefulness and ease of use. Interestingly, unlike the other applications in social psychology, it is hard to find such confusion in the concept of PBC in the studies for use of IT. In most of studies, controllability is adapted as PBC since the concept of self-efficacy is included in ease of use explicitly. Based on these discussions, we can suggest perceived use control(PUC) which is defined as perception of control over the performance of using IT and composed of controllability and ease of use as sub-concepts. We suggest a research model explaining acceptance of IT which includes the relationships of PUC with attitude and performance of using IT. For empirical test of our research model, two user groups are selected for surveying questionnaires. In the first group, there are freshmen who take a basic course for Microsoft Excel, and the second group consists of senior students who take a course for analysis of management information by Excel. Most of measurements are adapted ones that have been validated in the other studies, while performance is real score of mid-term in each class. In result, four hypotheses related with PUC are supported statistically with very low significance level. Main contribution of this study is suggestion of PUC through theoretical review of PBC. Specifically, a hierarchical model of PUC are derived from very rigorous studies in the relationship between self-efficacy and controllability with a view of PBC in social psychology. The relationship between PUC and performance is another main contribution.

• 한국식품저장유통학회지
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• 제19권4호
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• pp.470-476
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• 2012

신선편이 양상추는 유통 중 갈변과 이취 및 무름현상이 발생되고, 미생물의 증식에 의해 안전성이 위협받는 등 원재료보다 품질 저하현상이 빠르다는 문제점이 있다. 또한, 건강지향적인 시대가 도래함에 따라, 선도 유지를 위한 화학적 처리를 거친 식품은 기피하는 실정이다. 이에 일반적인 블랜칭의 단점을 보완할 수 있는 저온블랜칭과, 다른 기술과 병용처리 시 synergy effect를 기대할 수 있는 초음파를 병용처리함으로써 신선편이 양상추의 품질특성 변화에 대해 알아보고자 하였다. 최적 병용처리조건은 예비실험을 토대로 확립하였으며, central composite design에 의한 반응표면분석법을 이용하였다. 즉, 독립변수를 ultrasonication time ($x_1$), blanching temperature ($x_2$) 및 blanching time ($x_3$), 종속변수를 ${\Delta}E$ value (y)로 하여 반응표면분석을 실시한 결과, 90초간 ultrasonication한 후 $45^{\circ}C$에서 90초간 blanching (US+LB)하는 것이 색도 변화가 가장 적은 것으로 나타났다. 최적병용처리구와 각각의 단일처리구 및 무처리구를 $10^{\circ}C$에서 9일간 저장하면서 실험을 실시한 결과, 전반적으로 US+LB 처리구가 유의적으로 높은 $L^*$값이 나타났으며, $a^*$, $b^*$, ${\Delta}E$ value, browning index, PPO 및 POD 활성, 총균수에서 유의적으로 낮은 것으로 나타났다(p<0.05). 또한, appearance, color, aroma, freshness, texture, overall acceptibility의 6가지 항목으로 관능평가를 실시한 결과, 모든 항목에서 US+LB 처리구가 가장 우수한 것으로 나타나, 이화학적 실험결과와도 일치하는 경향임을 알 수 있었다. 이로써, 초음파와 저온블랜칭의 병용처리는 신선편이 양상추의 품질 유지에 효과적인 방법인 것으로 확인되었다.

• 수면정신생리
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• 제29권1호
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• pp.21-28
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• 2022

목적: 의과대학생들은 많은 스트레스를 받으며 점점 불안감이 높아지고 수면시간의 부족과 함께 수면양상도 불규칙 해진다. 따라서 의과대학생들의 일주기 유형, 수면의 질, 회복탄력성 그리고 불안이 어떠한 연관이 있는지 알아보고자 하였다. 방법: 경상국립대학교 의과대학생 본과 1학년 52명과 2년 후, 44명의 본과3학년 학생들을 대상으로 했다. 벡 우울 척도, 벡 불안 척도, 불면증 심각성 척도, 아침활동형 척도 그리고 코너-데이비드슨 탄력성 척도를 자기 설문지로 사용하였다. 각각의 상호 연관성을 알아보기 위하여 다중회귀 분석을 시행하였다. 결과: 본과 1학년 때의 불안이 높은 것은 2년 뒤인 3학년때 저녁형을 예측했고 본과 1학년때의 불안이 낮을수록 본과 3학년의 수면의 질이 좋았다. 본과 3학년의 수면의 질이 낮은 것은 저녁형 그리고 낮은 회복탄력성과 연관이 있었다. 또한, 본과 3학년의 우울감이 적은 것은 높은 회복탄 력성과 유의한 연관성을 보였다. 결론: 본 연구에서 의과대학생 본과 1학년 때의 불안의 정도가 2년 후 3학년 때의 수면의 질과 저녁형을 예측했다. 앞으로 1학년 학생들의 불안을 낮출 수 있는 방안을 고안하여 학생들의 수면의 질을 높이고 삶의 질을 향상시킬 필요가 있다.