• Title/Summary/Keyword: 불안정 영역

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Derivation and Evaluation of Surface Reflectance from UAV Multispectral Image for Monitoring Forest Vegetation (산림 식생 모니터링을 위한 무인기 다중분광영상의 반사율 산출 및 평가)

  • Lee, Hwa-Seon;Seo, Won-Woo;Woo, Choongshik;Lee, Kyu-Sung
    • Korean Journal of Remote Sensing
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    • v.35 no.6_2
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    • pp.1149-1160
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    • 2019
  • In this study, two radiometric correction methods deriving reflectance from UAV multispectral image for monitoring forest vegetation were applied and evaluated. Multispectral images were obtained from a small multispectral camera having 5 spectral bands. Reflectance were derived by applying the two methods: (1) the direct method using downwelling irradiance measurement and (2) the empirical line correction method by linking a set of field reflectance measured simultaneous with the image capture. Field reflectance were obtained using a spectroradiometer during the flight and used for building the linear equation for the empirical method and for the validation of image reflectance derived. Although both methods provided the high correlations between field reflectance and image-derived reflectance, their distributions were somewhat different. While the direct method provided rather stable and consistent distribution of reflectance all over the entire image area, the empirical method showed very unstable and inconsistent reflectance distribution. The direct method would be more appropriate for relatively wide area that requires more time to acquire image and may vary in downwelling irradiance and atmospheric conditions.

Synthesis and Crystallization of Amorphous Calcium Carbonate by Gas-Liquid Reaction of System Ca($OH_2 O$)-$H_2$-$CO_2$ (Ca($OH_2$)-$H_2 O$-$CO_2$계의 기액반응으로부터 비정질 탄산칼슘의 합성 및 결정화)

  • Im, Jae-Seok;Kim, Ga-Yeon;Im, Goeng
    • The Journal of Engineering Research
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    • v.5 no.1
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    • pp.73-87
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    • 2004
  • The synthesis and crystallization of amorphous calcium carbonate($CaCO_3$.$nH_2 O$) obtained from gas-liquid reaction between aqueous solution of calcium hydroxide and carbon dioxide at 15~$50^{\circ}C$ are investigated by electrical conductometry, XRD and TEM. The results are as follows: The initial reaction products prior to the formation of precipitated calcium carbonate is amorphous calcium carbonate. The electrical conductivity values in the slurry are decreased during the formation of amorphous calcium carbonate which covers particle surface of calcium hydroxide and retard the dissolution of calcium hydroxide into the solution. that amorphous calcium carbonate is unstable in the aqueous solution and crystallizes finally to calcite by the through-solution reaction. While amorphous calcium carbonate crystallizes into chain-like calcite, the conductivity values are recovered rapidly and the apparent viscosity of slurry containing higher concentration of calcium hydroxide increase. At below pH 9.5, chain-like calcite separates into individual particles to form precipitated calcium carbonate. The formation and synthetic temperature range of amorphous calcium carbonate is most suitable a primary decreasing step(a-step) at $15^{\circ}C$ in the electrical conductometry.

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A multiphase flow modeling of gravity currents in a rectangular channel (사각형 수로에서 중력류의 다상흐름 수치모의)

  • Kim, Byungjoo;Paik, Joongcheol
    • Journal of Korea Water Resources Association
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    • v.52 no.10
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    • pp.697-706
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    • 2019
  • A multiphase flow modeling approach equipped with a hybrid turbulence modeling method is applied to compute the gravity currents in a rectangular channel. The present multiphase solver considers the dense fluid, the less-dense ambient fluid and the air above free surface as three phases with separate flow equations for each phase. The turbulent effect is simulated by the IDDES (improved delayed detach eddy simulation), a hybrid RANS/LES, approach which resolves the turbulent flow away from the wall in the LES mode and models the near wall flow in RANS mode on moderately fine computational meshes. The numerical results show that the present model can successfully reproduce the gravity currents in terms of the propagation speed of the current heads and the emergence of large-scale Kelvin-Helmholtz type interfacial billows and their three dimensional break down into smaller turbulent structures, even on the relatively coarse mesh for wall-modeled RANS computation with low-Reynolds number turbulence model. The present solutions reveal that the modeling approach can capture the large-scale three dimensional behaviors of gravity current head accompanied by the lobe-and-cleft instability at affordable computational resources, which is comparable to the LES results obtained on much fine meshes. It demonstrates that the multiphase modeling method using the hybrid turbulence model can be a promising engineering solver for predicting the physical behaviors of gravity currents in natural environmental configurations.

Correlation between Behavioral Psychological Symptoms and Caregiver Burden in Alzheimer's Disease (알츠하이머병에서 행동심리증상과 간병인의 부양부담 사이의 상관관계)

  • Kim, Yo Sup;Lee, Kang Joon;Kim, Hyun
    • Korean Journal of Psychosomatic Medicine
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    • v.24 no.2
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    • pp.200-207
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    • 2016
  • Objectives : Alzheimer's disease(AD) is characterized by progressive decline of cognitive function and also by various behavioral psychological symptoms of dementia(BPSD) which causes distress to their caregivers. The purpose of this study was to investigate association between each AD patients' behavioral psychological symptoms and their caregivers' burden. Methods : Participants were 80 AD patients and their caregivers. We used Korean neuropsychiatric inventory (K-NPI) to assess the symptoms of patients and Korean version of Zarit Burden Interview(ZBI) to evaluate caregivers' burden. Results : The results showed ZBI score, which is the index for caregivers' burden, had a statistically significant positive correlation with the frequency of delusion, hallucination, agitation/aggression, depression, anxiety, disinhibition and irritability, the severity of hallucination, agitation/aggression, anxiety, disinhibition, aberrant motor, and sleep, and the global score(frequency${\times}$severity) for delusion, hallucination, agitation/aggression, depression, anxiety, disinhibition, aberrant motor, and sleep. There were significant correlations between each scale for cognitive function(i.e. MMSE-KC, CDR, GDS) and ZBI scale. Correlations between each scale for activity of daily living(i.e. Barthel -ADL, K-ADL) and ZBI scale were also significant. Conclusions : There were a significant correlation between BPSD and caregiver burden. Caregiver burden was also correlated with cognitive function and activity of daily living. Early detection and preventive treatment of these symptoms in BPSD might make improvement of caregivers' quality of life as well as AD patients'.

Experiences of Institutions Utilization among Homeless Young Men with Mental Health Problems: Inevitable Repeated Usages between Two Facility Systems behind the Deinstitutionalization (정신장애를 가진 노숙 청년의 시설 이용 경험 : 탈시설화의 이면(裏面), 생존을 위한 두 체계의 반복 이용을 중심으로)

  • Kim, Soyoung
    • Korean Journal of Social Welfare Studies
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    • v.48 no.3
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    • pp.83-116
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    • 2017
  • The purpose of this study is to raise the issue of the existing deinstitutionalization debate, considering only the shipment process to these two spaces, and still leaving the inter-facility circulation of vulnerable mental handicapped who are still hanging around the facility. In particular, we sought to supplement the discussion of deinstitutionalization by illuminating the problems of those who have to rely on facilities, as well as the mental health facility system and the homeless facility system. In the case of homeless persons with mental disabilities who repeatedly use the mental health facility system and the homeless facility system, they confirmed the pattern of using the facilities by constantly changing the place to manage the overlapping risk of mental illness and homelessness. Also it is triggered by the voluntary nature of the parties with no resources and resources. This situation appeared to be inevitable in the absence of resources and supportive systems that would actually enable a life in the community. Nevertheless, I asserted that the life of the mentally handicapped, which is circling the facility, is extremely unstable and is not desirable from a welfare point of view.

The Method for Colorizing SAR Images of Kompsat-5 Using Cycle GAN with Multi-scale Discriminators (다양한 크기의 식별자를 적용한 Cycle GAN을 이용한 다목적실용위성 5호 SAR 영상 색상 구현 방법)

  • Ku, Wonhoe;Chun, Daewon
    • Korean Journal of Remote Sensing
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    • v.34 no.6_3
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    • pp.1415-1425
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    • 2018
  • Kompsat-5 is the first Earth Observation Satellite which is equipped with an SAR in Korea. SAR images are generated by receiving signals reflected from an object by microwaves emitted from a SAR antenna. Because the wavelengths of microwaves are longer than the size of particles in the atmosphere, it can penetrate clouds and fog, and high-resolution images can be obtained without distinction between day and night. However, there is no color information in SAR images. To overcome these limitations of SAR images, colorization of SAR images using Cycle GAN, a deep learning model developed for domain translation, was conducted. Training of Cycle GAN is unstable due to the unsupervised learning based on unpaired dataset. Therefore, we proposed MS Cycle GAN applying multi-scale discriminator to solve the training instability of Cycle GAN and to improve the performance of colorization in this paper. To compare colorization performance of MS Cycle GAN and Cycle GAN, generated images by both models were compared qualitatively and quantitatively. Training Cycle GAN with multi-scale discriminator shows the losses of generators and discriminators are significantly reduced compared to the conventional Cycle GAN, and we identified that generated images by MS Cycle GAN are well-matched with the characteristics of regions such as leaves, rivers, and land.

The Lived Experience of Occupational Therapists in Public Health Centers Regarding Community Rehabilitation and Health Services: Phenomenological Study (보건소 작업치료사의 지역사회 재활 및 보건서비스 제공에 대한 업무 경험에 관한 현상학적 연구)

  • Park, Kang-Hyun;Jeon, Byoung-Jin;Jung, Min-Ye
    • Therapeutic Science for Rehabilitation
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    • v.10 no.1
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    • pp.63-75
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    • 2021
  • Objective : The purpose of this study was to examine the roles and practices of occupational therapists in public health centers based on their working experience of occupational therapists who are working in these facilities. Methods : We used Giorgi's descriptive phenomenological research method. Six occupational therapists were interviewed, and their recorded data were analyzed using Claizzi's thematic analysis. Results : As a result, 4 categories, 16 themes, and 24 elements were elicited. The major roles of occupational therapists in public health centers were the evaluation of clients, home-visit occupational therapy, management of dementia programs and community connection projects. Interventions that are needed to create a healthy community include case and program management, compensatory approaches, and healthy lifestyle interventions. The difficulties experienced by occupational therapists include their limited number job insecurity, performance-oriented administrative policy, and the lack of communication among professionals. Occupational therapists require education in health management and practice in public health centers to build their capacities. Conclusion : The results of this study could be used for guidelines for occupational therapists who work in community healthcare centers, as well as basic training for competent occupational therapists in the community.

The Relationship between Participative Leadership and Subordinates' Innovative Behavior: The Serial Multiple Mediating Effects of Knowledge Sharing and Creativity (참여적 리더십이 구성원의 혁신행위에 미치는 영향: 지식공유와 창의성의 직렬다중 매개효과)

  • Le Wang;Xiu, Jin
    • Journal of Industrial Convergence
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    • v.21 no.4
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    • pp.41-63
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    • 2023
  • Organizational members' innovative behavior is a key element that promotes organizational growth and sustainability. With today's unstable environment of economic and market , the importance of employees' innovative behavior is being emphasized. The reason is that employees' innovative behaviors play an important role in securing a organizational competitiveness. Based on this, this study focused on ways to improve employees' innovation behavior. Specifically, the causal relationship between participatory leadership and employees' innovative behavior was identified and the influence of innovative behavior was also verified. Furthermore, in the process of participatory leadership influencing employees' innovative behavior, the serial multiple mediating effect of knowledge sharing and creativity was verified. In order to demonstrate the hyphotheses, this study focused on 237 employees who work in Chinese SMEs. The results of the empirical analysis showed that participatory leadership had a positive effect on knowledge sharing, creativity, and innovative behavior. In addition, the serial multiple mediating effects of knowledge sharing and creativity on the relationship between participatory leadership and innovative behavior was significant. Overall, this study verified the positive role of participatory leadership that enhances employees' innovative behavior in Chinese SMEs and contributed to expanding the research field related to employees' innovative behavior through serial multiple mediating model.

Family Values and Caring Work of Single-Person Households in Ulsan: A Case Study (울산시 1인가구의 가족가치관 및 돌봄노동에 대한 사례연구)

  • Kwon, Anna
    • Journal of Family Resource Management and Policy Review
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    • v.27 no.2
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    • pp.35-47
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    • 2023
  • The purpose of this study was to understand family changes and dynamics of and to suggest institutional/policy-level tasks for coping with them, by paying attention to changing family values of single-person households and their caring work performed in everyday life. This study selected 11 single-person households residing in Ulsan by considering their age and marital status, and analyzed their overall daily lives, family values, and the characteristics of household work and caring. The characteristics of these single-person households in Ulsan, not only showed the coexistence of "simplicity, but instability" when maintaining and living their own lives, but also showed the ambivalent characteristics of family values by showing a gap between the perception and reality of diversity. In regard to family life, the participants complained of difficulties in "caring and relationship of family of origin" and the "economic factors", and notably showed the "dual value system". For a more stable life, the single-person households were forming social networks to relieve a sense of isolation and loneliness, and to recover relationships, instead of limiting themselves to only the traditional method of family formation. Thus, it would be possible to respond to family changes when changes are promoted in each area of "the perception of life", "family life", and the "family & social relationship", and this research suggests policy-level tasks based on the results of this study.

Residential Independence of Youth and Policy Implications (청년의 주거독립에 미치는 영향과 정책적 시사점)

  • Yoonhye Jung;Jinuk Sung
    • Land and Housing Review
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    • v.15 no.2
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    • pp.39-56
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    • 2024
  • This study addressed housing issues among various social problems of youth. With a focus on residential independence, this study analyzed the factors that lead youth to achieve residential independence. This study drew on nationwide data from the 'Youth Life Survey (2022)' with a sample size of 12,578. Binary logistic regression analysis was employed, with the dependent variable being residential independence. Key factors were as follows. The probability of residential independence was higher for men than women. Residential independence occurred mainly in non-metropolitan areas compared to metropolitan areas. Findings revealed that greater age, income, and assets facilitate achieving residential independence. In addition, public transport and cultural facilities were important for their residential independence, and it was found that the previous experience of residential independence had a positive effect. Policy implications derived from the findings are as follows. It is required to consider the heterogeneity and diversity of youth rather than implementing unitary policies. To ensure continuity and sustainability of self-reliance, long-term support programs are needed rather than temporary support. Moreover, it is required to offer public support comprehensively, instead of youth relying on support from personal networks, including their parents. An inclusive housing policy should be established to support youth for their residential independence in the future.