• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권6호
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• pp.2709-2734
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• 2020

The growing demand to make wireless data services 5G compatible has necessitated the development of an energy-efficient approach for an effective new wireless environment. In this paper, we first propose a cognitive sensor node (CSN) based game theory for deriving energy via a primary user-transmitted radio frequency signal. Cognitive users' time was segmented into three phases based on a time switching protocol: energy harvest, spectrum sensing and data transmission. The proposed model chooses the optimal energy-harvesting phase as the effected factor. We further propose a distributed energy-harvesting model as a utility function via pricing techniques. The model is a non-cooperative game where players can increase their net benefit in a selfish manner. Here, the price is described as a function pertaining to transmit power, which proves that the proposed energy harvest game includes Nash Equilibrium and is also unique. The best response algorithm is used to achieve the green connection between players. As a result, the results obtained from the proposed model and algorithm show the advantages as well as the effectiveness of the proposed study. Moreover, energy consumption was reduced significantly (12%) compared to the benchmark algorithm because the proposed algorithm succeeded in delivering energy in micro which is much better compared to previous studies. Considering the reduction and improvement in power consumption, we could say the proposed model is suitable for the next wireless environment represented in 5G.

• 한국정보통신학회논문지
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• 제22권6호
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• pp.881-887
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• 2018

스마트폰을 활용한 다양한 서비스들이 제공되면서 결제분야에서도 모바일을 이용한 다양한 서비스가 이루어지고 있다. 모바일 결제서비스는 금전적인 부분과 밀접한 관련이 있기 때문에 시스템의 여러 특성들이 사용 신뢰에 밀접한 영향을 끼치게 된다. 본 연구에서는 모바일 결제서비스의 시스템 중 중요 요인으로 접근성, 호환성, 보안성을 선정하였다. 이러한 시스템적 요인들이 사용자의 인지적 신뢰 및 긍정 감정 및 만족도와 같은 감성반응에 어떤 영향을 끼치는지 살펴보고자 한다. 이를 위해, 모바일 결제시스템 사용자를 대상으로 설문을 실시하였으며, 분석은 SPSS 23과 SmartPLS 2.0을 이용하였다. 분석 결과 모든 시스템 요인들이 인지적 신뢰 및 감성반응에 영향을 끼치는 것으로 나타났다. 하지만 감성 반응들 간의 관계를 살펴보면, 긍정감정은 만족도에 영향을 미치지 않는 것으로 나타났다.

• Biomolecules & Therapeutics
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• 제20권4호
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• pp.357-370
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• 2012

Radiation therapy, the most commonly used for the treatment of brain tumors, has been shown to be of major significance in tumor control and survival rate of brain tumor patients. About 200,000 patients with brain tumor are treated with either partial large field or whole brain radiation every year in the United States. The use of radiation therapy for treatment of brain tumors, however, may lead to devastating functional deficits in brain several months to years after treatment. In particular, whole brain radiation therapy results in a significant reduction in learning and memory in brain tumor patients as long-term consequences of treatment. Although a number of in vitro and in vivo studies have demonstrated the pathogenesis of radiation-mediated brain injury, the cellular and molecular mechanisms by which radiation induces damage to normal tissue in brain remain largely unknown. Therefore, this review focuses on the pathophysiological mechanisms of whole brain radiation-induced cognitive impairment and the identification of novel therapeutic targets. Specifically, we review the current knowledge about the effects of whole brain radiation on pro-oxidative and pro-inflammatory pathways, matrix metalloproteinases (MMPs)/tissue inhibitors of metalloproteinases (TIMPs) system and extracellular matrix (ECM), and physiological angiogenesis in brain. These studies may provide a foundation for defining a new cellular and molecular basis related to the etiology of cognitive impairment that occurs among patients in response to whole brain radiation therapy. It may also lead to new opportunities for therapeutic interventions for brain tumor patients who are undergoing whole brain radiation therapy.

• 생물정신의학
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• 제27권2호
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• pp.42-57
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• 2020

Electroconvulsive therapy (ECT) is indicated for various mental disorders (e.g., major depressive disorder, schizophrenia, and bipolar disorder) and the behavioral and psychological symptoms of dementia in elderly patients. Furthermore, ECT is a useful first-line treatment in emergency and crisis situations such as suicide risk, violent behavior, catatonia, and food refusal, which are more frequent in elderly patients. ECT is also effective in the treatment of the motor symptoms of neurological disorders, such as Parkinson's disease and Huntington's disease. Due to the high risk of various physical diseases, the comorbid physical conditions of elderly patients should be individually controlled to optimize ECT treatment. Compared to young adults, in elderly patients the seizure threshold is higher, the seizure duration is shorter, and the anesthetic dose is lower. On the contrary, the response rate in the elderly is both faster and higher. Considering potential cognitive decline and the prevention of further deterioration of cognitive function in elderly patients, in the absence of significant comorbidities, twice weekly sessions and right unilateral electrode placement with a lower seizure threshold and less cognitive effect are preferred to bilateral electrode placement, which has a high risk of adverse cognitive effects. After an acute course of ECT, continuation and maintenance of ECT, combined with prescription of therapeutic drugs, may prevent possible relapse or recurrence of mental disorders. In conclusion, ECT can be used to treat mental disorders in elderly adults, with safety and effectiveness comparable to that in young adults.

• 인간식물환경학회지
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• 제24권1호
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• pp.107-117
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• 2021

Background and objective: The purpose of this study is to investigate the effect of a forest healing program in terms of depression, neuropsychological and physiological benefits for the elderly. Methods: For this purpose, we developed a forest therapy program for the elderly who are vulnerable to dementia and conducted a total of 11 sessions of forest therapy activities in a forest once a week. We measured the changes in depression, resting-state Electroencephalography(EEG) and heart rate variability (HRV) before and after the program. There were 60 subjects aged over 65 yesrs old. 30 subjects participated in the forest therapy program, and the other were in the control group. The Geriatric Depression Scale was used to measure the level of depression, neuroNicle FX2 (Laxtha, Korea) was used to measure the resting-state EEG, and photoplethymogram (ubpulse T1, Laxtha, Korea) was used to measure the HRV. Results: The results showed that the depression index of the experimental group improved with statistical significance after the program (experiment group = 3.267 decrease of the mean). In the EEG measurement, the alpha-peak frequency at rest (experimental group = 0.227 Hz increase of the mean) was improved (mean increase = 0.23 in the experimental group, p < .05). The high frequency of HRV, which represents the parasympathetic nerve activity of the body's autonomous response, was also significantly improved (mean increase = 0.396 in the experimental group, p < .05). Conclusion: The results suggest that the forest therapy program can reduce the cognitive, psychological and physical risk factors of dementia for the elderly at risk of cognitive decline. Therefore, forest therapy activities may be suitable for the prevention of dementia in the elderly.

• 한국과학교육학회지
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• 제28권8호
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• pp.779-785
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• 2008

이 연구에서는 연소 개념 학습에서 변칙 사례의 역할을 인지적 동기적 측면에서 조사했다. 중학교 2학년 학생 433명을 대상으로 선개념 검사와 변칙 사례에 대한 반응 검사, 상황 흥미 검사를 실시했다. 연소 개념 학습을 실시한 후, 사후 검사로 주의집중, 노력, 개념 이해도 검사를 실시했다. 목표 오개념을 지닌 것으로 판별된 208명의 응답을 분석한 결과, 거부와 배제 반응의 비율은 밀도에 대한 선행연구의 결과와 비교하여 상대적으로 높은 반면, 신념 변화 반응의 비율은 낮은 것으로 나타났다. 경로 분석 결과, 대안 가설 제시 후의 상황 흥미가 직접적으로 또는 주의집중과 노력을 매개로 개념 이해도에 영향을 주는 것으로 나타났다. 변칙 사례에 의해 유발된 상황 흥미는 대안 가설 제시 후의 인지 갈등에 직접적으로 영향을 미치기도 했다.

• 한국과학교육학회지
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• 제28권5호
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• pp.359-382
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• 2008

다양한 개념변화이론이 존재하는 만큼 학습자들의 개념변화과정을 기술하기 위해 각각의 개념변화 이론에 열거된 분석대상이 다르다. 본 연구에서는 이러한 여러 가지 개념변화이론의 옳고 그름을 논의하지 않는다. 다만, 교실에서 일어나는 개념변화를 학습이라고 할 때 학습 과정을 설명하고 시사점을 얻기 위해서 기존의 이론을 고찰하여 정교화 시킬 필요성이 요구되었다. 본 연구에서는 학습이란 과제와 같은 주어진 맥락에 반응하여 학습자들이 갖고 있던 신념이 활성화되면서 새로운 개념구조를 구성하는 과정임을 이론적 고찰을 통해 이끌어내었다. 틀이론과 특정이론을 바탕으로 구성되는 정신모형에 대한 이론, 정보처리 이론에 바탕으로 둔 정신모형이론과 인지적 영역과 정의적 요인들을 통합한 정신모형 이론을 개략적으로 살피고 교실 수업에서 학습자가 구성하는 개념구조의 틀을 제안하였다. 또한 이것을 바탕으로 인지갈등을 새롭게 해석할 수 있는 개념구조적 갈등 모형을 제안하였다. 앞으로 이것을 이용하여 교실 수업에서 학습자들이 효과적으로 과학적 개념구조를 획득할 수 있는 방안들과 인지갈등을 포함한 개념변화에 대한 시사점을 얻을 수 있을 것으로 기대한다.

• 생물정신의학
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• 제22권2호
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• pp.78-86
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• 2015

Objectives Although ginseng has been reported to protect neuronal cells and improve various cognitive functions, relationship between ginseng supplementation and response inhibition, one of the important cognitive domains has not been explored. In addition, effects of ginseng on in vivo human brain have not been investigated using the diffusion tensor imaging (DTI). The purpose of the current study is to investigate changes in intrusion errors and white matter microstructure after Korean Red Ginseng supplementation using standardized neuropsychological tests and DTI. Methods Fifty-one healthy participants were randomly allocated to the Korean Red Ginseng (n = 26) or placebo (n = 25) groups for 8 weeks. The California Verbal Learning Test was used to assess the number of intrusion errors. Intelligence quotient (IQ) was measured with the Korean Wechsler Adult Intelligence Scale. Depressive and anxiety symptoms were evaluated using Hamilton Depression Rating Scale, Hamilton Anxiety Rating Scale, and Hopkins Symptom Checklist-25. The fractional anisotropy (FA) was measured from the brain DTI data. Results After the 8-week intervention, Korean Red Ginseng supplementation significantly reduced intrusion errors after adjusting age, sex, IQ, and baseline score of the intrusion errors (p for interaction = 0.005). Change in FA values in the left anterior corona radiata was greater in the Korean Red Ginseng group compared to the placebo group (t = 4.29, p = 0.04). Conclusions Korean Red Ginseng supplementation may be efficacious for improving response inhibition and white matter microstructure integrity in the prefrontal cortex.

• 한국과학교육학회지
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• 제37권5호
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• pp.891-909
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• 2017

이 연구는 과학 교육 현장에서 인지적 정의적 평가를 중심으로 한 양적 자료와 질적 자료에서 나타나는 몇 가지 불일치 사례를 분석했다. 308명의 고등학교 2학년 학생을 대상으로 학업 성취도와 정의적 성취도를 양적 자료로 수집했고, 그 중 33명의 학생을 면담한 질적자료를 분석했다. 주로 검사 도구의 측면에서 불일치 사례의 원인과 유형을 고찰했다. 연구 결과 양적 자료인 인지적 성취와 정의적 성취 영역 각각에서 과목별, 구인별 차이가 크게 나타나는 학생들이 상당수 있었고, 특히 두 영역 간 성취도 경향이 일치하지 않는 학생들도 20% 이상 분석되었다. 선택한 진로와 진학을 위해 의도적으로 과학 학습을 조절한 사례, 학교 과학과 과학에 대한 인식 차이에 따라 다른 반응 등의 사례가 면담을 통해 발견되었다. 도구로 측정한 양적 자료와 학생들의 면담 내용인 질적 자료를 비교한 결과 스스로 반응한 양적 자료와 다르게 자신을 평가하는 학생들이 대부분이었다. 이는 다양한 특성을 지닌 학생들이 검사 도구와 상호작용하는 과정에서 비롯된다. 검사 도구와 관련된 불일치 유형은 '문항 개발자가 의도한 개념과 학생들이 이해하는 개념 간 차이'와 '표현된 반응과 속마음 간의 차이'로 나타났다. 검사 도구에서 사용한 용어가 학생들에게 모호하게 인식될 때 자의적이거나 일관성 없이 반응하는 경우가 전자에, 사회적 바람직성이나 자아 방어 기제에 의한 반응 왜곡은 후자에 해당한다. 이상 연구 결과를 바탕으로 자기보고식 검사 도구가 학생들의 실제 인식을 잘 반영하고 있는지 검토하고 정교화하려는 노력, 학습 경험을 획일적으로 고정시키는 평가 개선 등이 필요하다.

• PNF and Movement
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• 제18권2호
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• pp.275-286
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• 2020

Purpose: The purpose of this study is to understand and analyze the current status of dementia management and rehabilitation services in Busan, South Korea, in response to the rapid increase of people with dementia due to the aging of the population. Methods: To investigate the current status of dementia rehabilitation in Busan, a survey was disseminated to dementia safety centers and day- and night-care centers in 16 districts/counties in Busan. Of the 209 day- and night-care centers, 23 institutes were registered in the National Health Insurance Service and received the highest grade (Grade A) in the institute evaluation that was implemented in each district. A telephone interview was conducted, and survey questions were related to the existence of an ongoing dementia rehabilitation program, program presenter, number of participants, progress method, program time, program duration, program contents, and participation path. Results: Dementia safety centers were implementing dementia prevention program, cognitive enhancing program, dementia program, self-help meeting and education program for family of dementia patient. The majority of the presenters of all four dementia-related programs were occupational therapists. The highest number of participants in the dementia prevention program was 15, and the highest number of participants in the cognitive enhancing program, dementia program, self-help meeting and education program for family of dementia patient was 10. All institutes' programs delivered group therapy. As for the time and frequency of the program, most dementia program included three-hour sessions five times a week. Most dementia prevention program, cognitive enhancing program, self-help meeting and education program for family of dementia patient included 60-minute sessions once a week. The most frequently observed program duration for the dementia prevention program and cognitive enhancing program was six months, and the most frequently observed duration for the dementia program was three months. Lastly, study participants most often reported that self-help meeting and education program for family of dementia patient lasted for two months. Among day- and night-care centers in Busan, programs related to cognition were implemented in 18 institutes, and the majority of the program presenters were social workers. Conclusion: In response to the rapidly growing number of dementia patients due to the aging of the population, this study examined the current status of dementia rehabilitation in Busan. The study results underscore the need to develop systems that consider the circumstances in Busan and continuously and systematically support dementia programs.