Multiplicity of positive solutions of a Schr\"odinger-type elliptic equation

고은경 영남수학회 2024 East Asian mathematical journal Vol.40 No.3

We investigate the existence of multiple positive solutions of the following elliptic equation with a Schr\"odinger-type term:$$\,\,\,\,\,\,\,\,\,\,\,\,\left\{\begin{array}{rlll}-\Delta u +V(x) u&=&\lambda f(u) & x \in\Omega,\\u &=&0, & x \in \partial\Omega,\end{array}\right. $$where $0 \in \Omega$ is a bounded domain in $ \mathbb{R}^N, N\geq 1,$ with a smooth boundary $\partial\Omega,$$f \in C [0,\infty)$, $V \in L^\infty (\Omega) $ and$\lambda$ is a positive parameter. In particular, when $f (s) >0 $ for $ 0 \leq s < \sigma $ and $f(s) <0$ for $s > \sigma,$ we establish the existence of at least three positive solutions for a certain range of $\lambda$ byusing the method of sub and supersolutions.

김석범 소설 『까마귀의 죽음』에 나타난 인물 형상화와 문학적 의미

고은경 제주대학교 인문과학연구소 2018 인문학연구 Vol.25 No.-

Hybrid Machine Learning 접근에 의한 유아교사의 포괄적 행복 척도 단축형 개발

고은경,전효정 한국아동학회 2023 한국아동학회 학술발표논문집 Vol.2023 No.11

학령기 아동의 정서 및 신체적 학대 사건에 대한 가정환경요인의 예측모델 평가

고은경,전효정 한국아동학회 2023 한국아동학회 학술발표논문집 Vol.2023 No.4

운동 착시 자극을 이용한 알츠하이머 환자, 정상노인, 대학생 집단의 운동지각 비교

고은경,정우현 한국임상심리학회 2010 Korean Journal of Clinical Psychology Vol.29 No.3

This study aimed to compare motion perception among college students, healthy elderly people, and patients with Alzheimers' disease(AD) using 2D or 3D illusory motion stimuli. The 3D illusory motion stimuli are static images but perceived moving forward and backward, and 2D perceived moving left or right. Significant group differences were found in motion perception, with the students performing best, healthy elderly people next, and the people with AD. And the people with AD performed better in 2D than 3D test. These results suggest impact of aging and disease status on motion perception and possibility of involving different mechanisms in 2D and 3D motion perception.

모사장치를 이용한 실험실 환경에서의 항공기 탑재전자장비 통합 시험

고은경,김성훈,양승열,김형진 한국항공우주학회 2015 한국항공우주학회 학술발표회 논문집 Vol.2015 No.11

항공기 개발 전 항공기에 탑재되는 전자장비들은 비행 시험 전 시스템 통합 시험환경인 SIL을 구성하여 사전 검증을 실시한다. 사전 검증 시험의 범위는 각 LRU의 상태정보 확인, 상위 장비인 비행조종컴퓨터 및 통합관리컴퓨터의 통제에 의한 기능 수행, 하부 연동 센서와의 연동과 센서 상태정보 전송으로 구분할 수 있다. LRU간 통신 및 LRU와 하부 센서와의 통신 프로토콜은 실제 비행체의 프로토콜과 동일해야 하며, 통신, LRU 및 센서의 고장을 모의함으로서 비상상황에서의 로직 확인이 포함되어야 한다. 본 논문에서는 기존의 SIL 시험 시 LRU 기능 및 하부 센서 연동모의를 통합한 Simulator를 개발하여 SIL환경 검증을 진행하는 모델을 발전시켜, 실제 항공기에서와 동일한 통신 프로토콜을 이용하여 LRU와 연동하는 하드웨어 및 소프트웨어 모사장치를 설계하여 비행체 탑재 전자장비 시험 모델 및 시험 수행결과에 대하여 설명하였다. 논문에서 제시한 방법을 통해 실제 항공기 연동 형상과 더욱 유사한 시스템을 구축함으로써 통합시험의 신뢰도 향상을 기대할 수 있다. On the process of developing aircraft, all the aircraft electrical equipment should be tested a prior analysis in the SIL environment before performing the flight test. The boundary of prior analysis contains LRU status check, functionality check under control by higher level LRU(flight computer or mission computer), and interactions with the lower level sensor and transferring its status. This paper introduce contemporary experiment environments that is developed from the current SIL experiment model which integrated LRU functions and interface with its lower level sensor into one simulator. The new model consists of hardware and software units which send the replicated sensor signals and communicate with real LRU with same interface as the uses in real aero vehicle. This advanced experiment method is expected to provide increased reliability by constructing more similar configurations with the real aircraft.

Toxicity of antioxidative extract collected from Styela clava tunics in ICR mice

고은경,성지은,김지은,고준,송성화,이현아,손홍주,정영진,임용,황대연 한국실험동물학회 2015 Laboratory Animal Research Vol.31 No.3

Some polymers and bioactive compounds derived from Styela clava tunic (SCT) have been reported as traditional medicine for the treatment of inflammation, oxidative stress and surgical wounds although there is little scientific evidence of their liver and kidney toxicity. To investigate the toxicity of ethanol extracts of SCT (EtSCT) in the liver and kidney of ICR mice, alterations in related markers including body weight, organ weight, urine composition, liver pathology and kidney pathology were analyzed following oral administration of 50 and 100 mg/kg body weight/day of EtSCT for 14 days. EtSCT showed a high level of free radical scavenging activity for DPPH (93.1%) and NO (16.2%) as well as the presence of 14.8 mg/ mL of flavonoids and 36.2 mg/mL of phenolics, while EtSCT treated groups did not show any significant alterations in the body and organ weight, clinical phenotypes, urine parameters or mice mortality when compared with the vehicle treated group. In addition, constant levels of serum biochemical markers including alanine phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN) and serum creatinine (CRE) were maintained. Moreover, no specific histopathological features induced by most toxic compounds were observed in liver and kidney sections stained with hematoxilin and eosin. Therefore, the present results indicate that EtSCT with strong antioxidant activity cannot induce any specific toxicity in liver and kidney organs of ICR at doses of 100 mg/kg body weight/day.

情報技術市場에서의 獨占禁止法 適用에 관한 硏究 : 美國 Microsoft社 事例를 中心으로

고은경 중앙대학교 법학대학 2002 法政論叢 Vol.37 No.-

Beneficial effect of diosgenin as a stimulator of NGF on the brain with neuronal damage induced by Aβ-42 accumulation and neurotoxicant injection

고은경,윤우빈,김지은,송성화,성지은,이현아,서은지,지승완,배창준,황대연 한국실험동물학회 2016 Laboratory Animal Research Vol.32 No.2

To investigate the beneficial effects of diosgenin (DG) on the multiple types of brain damage induced by Aβ-42 peptides and neurotoxicants, alterations in the specific aspects of brain functions were measured in trimethyltin (TMT)-injected transgenic 2576 (TG) mice that had been pretreated with DG for 21 days. Multiple types of damage were successfully induced by Aβ-42 accumulation and TMT injection into the brains of TG mice. However, DG treatment significantly reduced the number of Aβ-stained plaques and dead cells in the granule cells layer of the dentate gyrus. Significant suppression of acetylcholinesterase (AChE) activity and Bax/Bcl-2 expression was also observed in the DG treated TG mice (TG+DG group) when compared with those of the vehicle (VC) treated TG mice (TG+VC group). Additionally, the concentration of nerve growth factor (NGF) was dramatically enhanced in TG+DG group, although it was lower in the TG+VC group than the non-transgenic (nTG) group. Furthermore, the decreased phosphorylation of downstream members in the TrkA high affinity receptor signaling pathway in the TG+VC group was significantly recovered in the TG+DG group. A similar pattern was observed in p75NTR expression and JNK phosphorylation in the NGF low affinity receptor signaling pathway. Moreover, superoxide dismutase (SOD) activity was enhanced in the TG+DG group, while the level of malondialdehyde (MDA), a marker of lipid peroxidation, was lower in the TG+DG group than the TG+VC group. These results suggest that DG could exert a wide range of beneficial activities for multiple types of brain damage through stimulation of NGF biosynthesis.

유아교사의 대상관계 및 교사효능감과 교수스트레스와의 관계

고은경,정계숙,손환희,하은실 한국영유아교원교육학회 2011 유아교육학논집 Vol.15 No.2

This study aimed to find the relationships with object relations, teacher efficacy and teaching stress of early childhood teachers. The subjects were 199 early childhood teachers answered the Object Relations Scale, Teacher Efficacy Scale, and Teaching Stress Scale. The results were as follows; First, there were positive correlations between total and subscale scores of object relations and teaching stress. In addition, there were negative correlations between the scores of teacher efficacy and teaching stress. Second, from multiple linear regression analyses of the variables, object relations variable accounted for 30% of teaching stress of teachers and teacher efficacy variable added further 23% of the accountability. The degree of accountability of whole variable and sub-variables of object relations and teacher efficacy on the variables of teaching stress were different. Finally, the implications for teacher education and research limitations were discussed. 본 연구는 유아교사의 대상관계와 교사효능감은 교수스트레스와 어떤 관계가 있는지를 알아보는데 주된 목적이 있다. 이를 위해 부산, 경남, 경북에 거주하는 유아교사 199명을 대상으로 대상관계 척도, 교사효능감 척도, 교수스트레스 척도를 사용하여 설문조사를 실시하였다. 연구결과, 첫째, 유아교사의 대상관계와 교수스트레스는 정적 상관관계인 것으로 나타났고, 교사효능감과 교수스트레스는 부적 상관관계인 것으로 나타났다. 둘째, 중다선형 회귀분석 결과, 유아교사의 교수스트레스에 대해 대상관계는 30%의 독립적인 설명이 가능하며 교사효능감은 23%의 추가적인 설명을 할 수 있는 것으로 나타났다. 대상관계와 교사효능감 변인의 교수스트레스의 4개 하위변인에 대한 설명력은 하위변인에 따라 차이가 있었다. 이러한 결과에 대한 제한점과 시사점을 논의하였다.