• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2020년도 학술발표회
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• pp.171-171
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• 2020

Decision making strategies should consider both adaptiveness and robustness in order to deal with two main characteristics of climate change: non-stationarity and deep uncertainty. Especially, robust strategies are different from traditional optimal strategies in the sense that they are satisfactory over a wider range of uncertainty and may act as a key when confronting climate change. In this study, a new framework named Robust Stochastic Dynamic Programming (R-SDP) is proposed, which couples previously developed robust optimization (RO) into the objective function and constraint of SDP. Two main approaches of RO, feasibility robustness and solution robustness, are considered in the optimization algorithm and consequently, three models to be tested are developed: conventional-SDP (CSDP), R-SDP-Feasibility (RSDP-F), and R-SDP-Solution (RSDP-S). The developed models were used to derive optimal monthly release rules in a single reservoir, and multiple simulations of the derived monthly policy under inflow scenarios with varying mean and standard deviations are undergone. Simulation results were then evaluated with a wide range of evaluation metrics from reliability, resiliency, vulnerability to additional robustness measures. Evaluation results were finally visualized with advanced visualization tools that are used in multi-objective robust decision making (MORDM) framework. As a result, RSDP-F and RSDP-S models yielded more risk averse, or conservative, results than the CSDP model, and a trade-off relationship between traditional and robustness metrics was discovered.

• 한국사회복지학회:학술대회논문집
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• 한국사회복지학회 2004년도 춘계학술대회 자료집
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• pp.365-382
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• 2004

The purpose of this study was to explore the concepts of health among people with mobility disabilities in order to develop a new holistic model of health and to identify implications for social work practice. A qualitative study based on face-to-face interviews with people with mobility disabilities was conducted. Nine consumers and nine social workers with mobility disabilities participated in the study. Social constructionism, heuristic paradigm, empowerment paradigm, and strength perspectives were used to form conceptual foundations to guide the study. Study participants' holistic descriptions of the concept of health encompassed five domains: biological/physical, mental/emotional, financial, relationships with others, and spiritual. Participants described health as harmony among these five domains. Harmony indicates that all five domains contribute to the concept of health, and that each domain is related to the others. Participants also viewed disability and health as an interconnected whole, not separate concept. The conceptual model developed in this study expands on the existing concepts of health by considering multiple factors at the personal and environmental levels, as well as interactions among the factors and between the levels. The personal level has five domains: biological/physical, mental/emotional, spiritual, financial, and relationships with others. The environmental level has also five domains: relationship with others, financial, social programs, social attitudes toward peoplewith disabilities, and physical environment. All factors under the personal and environmental levels also affect each other. The holistic concept of health for people with disabilities is not solely a part of the person, but rather is a function of the interaction between the person and their environment. The study demonstrated that people with disabilities have strength and resiliency, and health is an attainable goal for them, particularly when environmental and cultural barriers are addressed. The focus of social work practice should be the removal of those barriers encountered by their consumers with disabilities, as well as, the enhancement of internal factors that facilitate well-being.

• 한국통신학회논문지
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• 제34권1C호
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• pp.90-97
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• 2009

OFDM (Orthogonal Frequency Division Multiplexing) 전송방식의 장점은 높은 주파수 효율, RF간섭에 대한 강인성, 낮은 다중 경로 왜곡 등을 들 수 있다. 다중 사용자 OFDM의 채널용량을 확대하기 위해서는 사용자간의 부채널과 비트 할당의 효율적인 알고리즘을 개발하여야 한다. 본 연구에서는 다중 사용자의 전송요구량을 만족하는 최적 부채널 및 비트 할당 문제를 0-1 정수계획법 모형으로 형성하고, 원래 문제의 선형계획법 완화 (linear programming relaxation)문제를 dual-decomposition과 subgradient 알고리즘을 사용하여 해를 구하는 효과적인 알고리즘을 제시한다. 또한 dual-decomposition으로 구한 목적함수값은 원래 문제의 선형계획법 완화문제의 최적목적함수 간과 동일함을 증명하였다 모의실험을 통하여 다수의 문제에 대하여 원래 문제의 최적 목적항수값에 대한 dual-decomposition으로 구한 하한의 성능을 제시하였다. MQAM (M-ary Quadrature Amplitude Modulation)을 사용하고 3개의 독립적인 Rayleigh 다중 경로로 구성된 주파수 선택적 채널을 가정한 경우 MATLAB을 사용한 모의실험에서 0-1 정수계획 법으로 구한 최적해의 성능을 실험하였다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2006년도 학술발표회 논문집
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• pp.312-317
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• 2006

지역규모의 기후변화 모의결과를 이용하여 금강유역 용담댐의 홍수기 치수안전도에 대한 민감도분석을 수행하였다. 기후변화 모의에 사용된 SNURCM(Seoul National University Regional Climate Model)은 미국 National Center for Atmospheric Research의 Community Climate System Model의 전지구모형을 기반으로 spectral nudging 기법을 사용한 공간해상도 30 km, 연직 21층의 지역기후모형이다. 기후변화 시나리오로는 SRES 'B1'이 사용되었으며 과거 control run에 대한 기후모의 정확도 분석을 통하여 SNURCM 기상자료를 관측치와 비교한 결과 면적강우량을 다소 과소추정하였고 이점을 감안하여 SNURCM의 일 모의결과에 보정 계수를 적용하였다. 하천유출량은 SSARR 모형을 이용하여 SNURCM 모의가 수행된 전체기간을 $1980{\sim}1999$년과 $2000{\sim}2019$년으로 20년씩 나누어 용담댐 일 유입량을 산정하여 통계분석을 실시하였고 과거와 미래 20년 동안을 비교하여 본 결과 (1) 유량의 평균보다는 분산이 미래 20년 동안 증가하여 가뭄과 홍수에 대한 위험도가 증가함을 알 수 있었고, (2) 특히 연최대유량 또한 미래 20년 동안 상당히 증가하여 홍수기 치수대책이 더욱 중요해질 것으로 판단되었다. 마지막으로 용담댐 운영은 범용 시스템분석 도구인 STELLA(System Thinking Experimental Learning Laboratory with Animation) 상에서 GUI로 구현하여 유입량 변화에 따른 용담댐 치수안전도 변화를 모의해 보았다. 용담댐의 홍수기 운영은 저수지 수위가 제한수위를 초과하기 시작하면 Rigid ROM 발효하여 방류량을 결정하도록 구성하였고, 무효방류(spill)가 일어나는 현상을 실패로 가정하여 이에 대한 신뢰도(reliability), 회복도(resiliency), 그리고 심도(vulnerability)를 치수안전도 지표로 계산하였다. 전체기간을 1980년${\sim}$1999년, 2000년${\sim}$2019년, 2000년${\sim}$2009년, 그리고 2010년${\sim}$2019년까지 총 4구간으로 나누어 결과를 도출하였으며 예상한 바와 같이 후반기 20년 동안에 세 가지 지표가 취약해 지는 것을 확인할 수 있었고, 특히 2000년부터 2009년까지 10년 동안에는 더욱 취약해짐을 확인할 수 있었다.

• 대한토목학회논문집
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• 제33권4호
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• pp.1389-1400
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• 2013

본 연구에서는 농업용 둑높임저수지의 다중용수공급능력(관개 및 하천유지용수) 평가에 따른 이수운영기준곡선을 개발하였다. 20개 둑높이기 사업지구를 대상으로 특성분석에 따른 4개(웅양, 궁촌, 용암, 운암)의 대표 저수지를 선정하고, 이수운영모형을 이용한 물수지분석을 통해 하천유지용수 공급 가능량을 산정하였다. 이수운영기준은 관개기와 비관개기에 대해 방류제한수위(사업전 만수위)에서 상시만수위까지의 저수위구간을 하천유지용수공급 가능 수위로 설정하고 신뢰도, 회복도 및 취약도 지수를 이용하여 각 둑높임저수지 특성별 물공급 능력을 평가하였다. 이수운영기준 적용에 따른 둑높임저수지의 이수운영기준곡선은 과거 이수운영모의결과로부터 일별 저수위를 백분위(Percentile Rank)로 표현하였다. 각 분위별 저수위 구간을 3개의 완충구간(Buffer)으로 나누어 갈수년(5~25%), 평수년(25~75%) 및 풍수년(75~95%)에 해당하는 저수지 운영이 가능하도록 하였다.

• 기본간호학회지
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• 제23권3호
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• pp.310-319
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• 2016

Purpose: This study was done to examine whether risk of suicidal ideation in nursing students as related to social support and ego-resilience, and whether subjective wellbeing mediated the relationships. Methods: Structural equation modeling was applied to test the model in which ego-resilience and social support from family, friends, and others were considered as exogenous variables and subjective wellbeing as a mediating variable. The participants were 285 nursing students who completed self-report measures including the Suicidal Ideation Questionnaire, the Multidimensional Scale of Perceived Social Support, the Ego-Resiliency Scale, and the Index of Wellbeing. Results: Results show that higher scores on family support and ego-resilience were positively associated with subjective wellbeing and negatively with suicidal ideation. Subjective wellbeing mediated the relationships between family support and suicidal ideation, and also ego-resilience and suicidal ideation. Among the three social supports, only family social support had both direct and indirect effects on suicidal ideation. Conclusion: Findings suggest that family support is a useful resource in the prevention of suicidal ideation in nursing students and building supportive relationship with family should be considered as the first step in suicide prevention strategies. Also enhancing ego-resilience could play an important role to reduce suicide risk through promoting well-being.

• 사회복지연구
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• 제42권3호
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• pp.33-56
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• 2011

본 연구는 손자녀 양육이 조부모의 우울감에 미치는 영향을 파악하고, 사회적 지지의 매개효과 및 가구유형이 손자녀 양육과 조부모의 우울감에 미치는 조절효과를 분석하는데 목적이 있다. 본 연구는 2006년 고령화연구패널조사를 기초로 2차 자료 분석을 하였으며, 패널조사 응답자 중 손자녀를 양육하고 있는 중고령자 555명을 대상으로 하였다. 연구결과, 손자녀를 양육하는 시간과 손자녀를 양육하는 기간 모두 조부모의 우울감을 증가시키는 요인으로 나타났다. 사회적 지지가 적을 수록 조부모의 우울감이 증가하는 것으로 나타났으나 사회적 지지의 매개효과는 유의미하지 않았다. 가구유형에 따른 손자녀 양육과 조부모의 우울감의 관계는 유의미하지 않은 것으로 나타났다. 연구결과를 바탕으로 손자녀를 양육하는 조부모에 대한 사회복지의 실천적 함의를 제시하였다.

• Asia pacific journal of information systems
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• 제33권4호
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• pp.863-898
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• 2023

Previous studies have shown that insiders pose risks to the security of organisations' secret information. Information security policy (ISP) intentional violation can jeopardise organisations. For years, ISP violations persist despite organisations' best attempts to tackle the problem through security, education, training and awareness (SETA) programs and technology solutions. Stopping hacking attempts e.g., phishing relies on personnel's behaviour. Therefore, it is crucial to consider employee behaviour when designing strategies to protect sensitive data. In this case, organisations should also focus on improving employee behaviour on security and creating positive security perceptions. This paper investigates the role of psychological capital (PsyCap), punishment and organisational security resources in influencing employee behaviour and ultimately reducing ISP violations. The model of the proposed study has been modified to investigate the connection between self-efficacy, resilience, optimism, hope, perceived sanction severity, perceived sanction certainty, security response effectiveness, security competence and ISP violation. The sample of the study includes 364 bank employees in Jordan who participated in a survey using a self-administered questionnaire. The findings show that the proposed approach acquired an acceptable fit with the data and 17 of 25 hypotheses were confirmed to be correct. Furthermore, the variables self-efficacy, resilience, security response efficacy, and protection motivation directly influence ISP violations, while perceived sanction severity and optimism indirectly influence ISP violations through protection motivation. Additionally, hope, perceived sanction certainty, and security skills have no effect on ISP infractions that are statistically significant. Finally, self-efficacy, resiliency, optimism, hope, perceived severity of sanctions, perceived certainty of sanctions, perceived effectiveness of security responses, and security competence have a substantial influence on protection motivation.

• Child Health Nursing Research
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• 제2권2호
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• pp.45-57
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• 1996

A serious disease in a family influences the entire family member given the fact that the members closely interact with each other. Especially in terms of pediatric nursing, study on family gains importance as the need to care of families whose children with developmental disabilities and chronic disease This study was done based on The Resiliency Model of Family Adjustment and Adaptation(McCubbin, 1991) is intended to examine the stress of parents whose children suffer from cleft lip or /and cleft palate. It also helps them to cope with the stress and analyze the relationship between the stress and coping This study used Family Inventory of Life Events and Changes (FILE) and Coping Health Inventory for Parents(CHIP) for measuring family stress and coping. The two instruments are revised to fit the social and cultural environment of Korean culture. Data collection was done from April 18, 1996 to May 18, 1996 at 8 University medical centers located in Seoul. Those who answered questionnaires were 84 parents whose children have cleft lip or /and cleft palate. SPSS PC+ was used to analyze the data collotted. Programs used for data analysis were t-test, ANOVA, Pearson correlation coefficient. The study is summarized as follows .1. The average score of family stress is 10.46(percentage of the full score 24.90) and 'finance and business strains'(3.25), and 'intrafamily strains'(2.65) ranked the highest. The average score of family's coping is 1.93, which is close to the answer of' moderately helpful' and they are measured to put their utmost efforts to' intergration and cooperation of family and optimistic definition on the situation'. 2. There is no significant statistical correlation between the family stress and coping. 3. Mothers show more stress than fathers in the parts of 'illness and family care strains' and 'losses'(t〓-2.34, t〓-2.32, p<.05). 4. Fathers show more willingness to cope with the stress than mothers do in the parts of' seeking social support','self-esteem','emotional comfort' 5. Mothers are more stress than fathers in the parts of family stress and its coping with it by usual traits(t〓-2.78, p<.05). Parents with religion are measured to cope more willingly than those who are not 6. Income of a family shows positive correlationship with family coping (r〓.28, p<.05). The study shows that gender difference is significant variable in studying on family stress and coping. Mothers get more stress than fathers, which has much to do with the fact that they are in charge of raising children and keeping houseworks. Accordingly, managing family crisis and its survival can be induced by giving support for the mothers, studying fathers including the rest of the family members and giving nursing care and arbitration ; religious background is also considered to be one of the important factors in family stress , judging from the relationship between family income and family's coping, caring given to suffering children is needed on societal levels. The above considerations bring up the need to have a longitudinal study of children with congenital anomaly including cleft lip or /and cleft palate and their families about family stress and coping. Resiliency programs on family system and their effectiveness and the relationship between the enlarged families with social and cultural values reflecting Korean tradition are also needed to be studied.

• 한국수자원학회논문집
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• 제47권10호
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• pp.891-906
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• 2014

본 연구는 수계관리 측면에서 물 공급의 기준이 되는 하류 제어지점에서 발생할 수 있는 물 부족을 최소 허용하면서 저수지군 최적 운영방안을 제공할 수 있도록 위험도 평가기준을 목적함수 및 제약조건에 반영한 hedging rule을 혼합정수계획법(MIP, Mixed Integer Programming)으로 구성하고 이에 대한 이행도를 분석함으로써 기존의 용수공급 신뢰도에 중점을 두었던 저수지군 최적 운영 분석기법을 개선하고자 하였다. 이를 위해 한강수계 5개 저수지(소양강댐, 충주댐, 화천댐, 청평댐, 팔당댐)군을 대상으로 수계관리를 위한 모형을 구축하였으며, 한강수계 내에 총 8개의 가상 제어지점을 구성하여 댐 하류 제어지점에서의 물 부족에 대해 위험도를 평가하였으며, 개발된 hedging rule의 적정성을 검증하기 위하여 2개의 유입량 계열('93. 1월~'97. 12월, '99. 1월~'03. 12월)에 대하여 적용 검토하였다. 팔당댐 하류 제어지점의 월별 최소유량을 비교하면 '93. 1월~'97. 12월의 모의기간에서는 hedging rule 적용 시 $317.5{\times}10^6m^3$으로 단독운영의 $310.6{\times}10^6m^3$, 연계운영의 $56.3{\times}10^6m^3$ 보다 많은 유량을 보였으며, '99. 1월~'03. 12월의모의기간에서도 hedging rule 적용시 $243.7{\times}10^6m^3$ 으로 단독운영의 $204.2{\times}10^6m^3$, 연계운영의 $111.2{\times}10^6m^3$에 비해 최소 유량이 많은 것을 확인하였으며, 이는 제안한 hedging rule에 의해 하류 제어지점에서의 최대 물 부족량이 감소하는 결과를 보여주고 있다.