• Title/Summary/Keyword: Sub-Strategies

Search Result 652, Processing Time 0.027 seconds

Improvement of the GA's Convergence Speed Using the Sub-Population (보조 모집단을 이용한 유전자 알고리즘의 수렴속도 개선)

  • Lee, Hong-Kyu;Lee, Jae-Oh
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.15 no.10
    • /
    • pp.6276-6281
    • /
    • 2014
  • Genetic Algorithms (GAs) are efficient methods for search and optimization problems. On the other hand, there are some problems associated with the premature convergence to local optima of the multimodal function, which has multi peaks. The problem is related to the lack of genetic diversity of the population to cover the search spaces sufficiently. A sharing and crowding method were introduced. This paper proposed strategies to improve the convergence speed and the convergence to the global optimum for solving the multimodal optimization function. These strategies included the random generated sub-population that were well-distributed and spread widely through search spaces. The results of the simulation verified the effects of the proposed method.

Factors Related to the Medical Service Performance of Rural Health Sub-centers (농어촌 보건지소 진료실적과 관련 요인)

  • Lee, Su-Jin;Na, Baeg-Ju
    • Journal of agricultural medicine and community health
    • /
    • v.35 no.4
    • /
    • pp.350-360
    • /
    • 2010
  • Objectives: This study was conducted to identify factors that affect medical service performance in rural health sub-centers and to develop a method to improve health sub-center performance that takes advantage of these insights. Methods: This study included 1,242 South Korean health sub-centers that had been in operation at least since December 31, 2009 as units of analysis. After adjusting for population differences between areas, the performance of medical service among health sub-centers was analyzed according to medical services performed per person. We performed t-tests, ANOVA, Scheffe's tests and multiple regression analyses. Results: The following were significant variables affecting the medical service performance of rural health sub-centers: number of hospitals and clinics, presence of community health practitioner posts, distance from health sub-centers to main public health centers, distance from health sub-centers to the nearest emergency medical facilities, and proportion of the local population aged 65 and over. In contrast, the proportion of the local population between ages 0-4 and the placement of public health doctors that had already completed their internship were not significant variables. Conclusions: The medical service performance of health sub-centers located in rural areas is significantly affected by local population and health care environment characteristics, and therefore, it is imperative to develop strategies to provide differentiated service based on these factors.

Geochemical Modeling on Behaviors of Radionuclides (U, Pu, Pd) in Deep Groundwater Environments of South Korea (한국 심부 지하수 환경에서의 방사성 핵종(우라늄, 플루토늄, 팔라듐)의 지화학적 거동 모델링)

  • Jaehoon Choi;SunJu Park;Hyunsoo Seo;Hyun Tai Ahn;Jeong-Hwan Lee;Junghoon Park;Seong-Taek Yun
    • Economic and Environmental Geology
    • /
    • v.56 no.6
    • /
    • pp.847-870
    • /
    • 2023
  • The safe disposal of high-level radioactive waste requires accurate predictions of the long-term geochemical behavior of radionuclides. To achieve this, the present study was conducted to model geochemical behaviors of uranium (U), plutonium (Pu), and palladium (Pd) under different hydrogeochemical conditions that represent deep groundwater in Korea. Geochemical modeling was performed for five types of South Korean deep groundwater environment: high-TDS saline groundwater (G1), low-pH CO2-rich groundwater (G2), high-pH alkaline groundwater (G3), sulfate-rich groundwater (G4), and dilute (fresh) groundwater (G5). Under the pH and Eh (redox potential) ranges of 3 to 12 and ±0.2 V, respectively, the solubility and speciation of U, Pu, and Pd in deep groundwater were predicted. The result reveals that U(IV) exhibits high solubility within the neutral to alkaline pH range, even in reducing environment with Eh down to -0.2 V. Such high solubility of U is primarily attributed to the formation of Ca-U-CO3 complexes, which is important in both G2 located along fault zones and G3 occurring in granitic bedrocks. On the other hand, the solubility of Pu is found to be highly dependent on pH, with the lowest solubility in neutral to alkaline conditions. The predominant species are Pu(IV) and Pu(III) and their removal is predicted to occur by sorption. Considering the migration by colloids, however, the role of colloid formation and migration are expected to promote the Pu mobility, especially in deep groundwater of G3 and G5 which have low ionic strengths. Palladium (Pd) exhibits the low solubility due to the precipitation as sulfides in reducing conditions. In oxidizing condition, anionic complexes such as Pd(OH)3-, PdCl3(OH)2-, PdCl42-, and Pd(CO3)22- would be removed by sorption onto metal (hydro)oxides. This study will improve the understanding of the fate and transport of radionuclides in deep groundwater conditions of South Korea and therefore contributes to develop strategies for safe high-level radioactive waste disposal.

Effects of Temperament and Stress Coping Strategies on Psychological Well-Being of Adolescents (청소년의 기질과 스트레스 대처전략이 심리적 안녕감에 미치는 영향)

  • Lee, Sang-Mee;Lim, JungHa
    • Journal of Korean Home Economics Education Association
    • /
    • v.27 no.2
    • /
    • pp.121-135
    • /
    • 2015
  • The purpose of this study was to investigate the influence of temperament and stress coping strategies on adolescents' psychological well-being. Three hundred and ninety nine middle and high school students in Seoul participated in this study. Temperament, stress coping strategies, and psychological well-being were evaluated by self-report questionnaires. Data were analyzed using Cronbach's alpha, frequencies, percentiles, means, standard deviations, two-way ANOVAs, Pearson's correlations and hierarchical multiple regression analyses. The results were as follows: First, there were significant differences in psychological well-being as a function of gender and school levels. Second, temperament and stress coping strategies were related to psychological well-being in adolescents. In the sub factor of temperament, activity and persistency were positively associated with psychological well-being, whereas rigidity was negatively related to psychological well-being. Among stress coping strategies, problem-focused strategy was positively associated with psychological well-being, whereas emotion-discharge strategy and affective-regulation strategy were negatively related to psychological well-being. Third, hierarchical multiple regression revealed that problem-focused strategy and emotion-discharge strategy were influential factors in explaining the level of psychological well-being controlling for gender, school levels and temperament of the adolescents. These findings suggest that stress coping strategy should be considered to promote the level of psychological well-being of adolescents.

  • PDF

An Analysis on Choice Factors of Food Court Customers to Co-Branding Strategies (공동 브랜드 전략을 위한 푸드 코트 이용고객의 선택속성 분석)

  • Hong, Yeo-Wool;Choi, In-Sub;Na, Tae-Kyun
    • Culinary science and hospitality research
    • /
    • v.13 no.1 s.32
    • /
    • pp.1-10
    • /
    • 2007
  • Co-branding of food courts is turning into a trend with the activation of recent entrance of famous restaurants into shopping departments and other large-size buildings. This research analyzes the effects of co-brand food courts on the choices of dining enterprises by dealing with the customers of these newly activated food courts in shopping malls and large-size buildings. By analyzing the effects of the present status of customers' using food courts according to the characteristics of their choices of dining enterprises, food and brand elements were found to have an effect on the restaurant brand recognition of food courts, and price factor was found to have an effect on an visitors' recommendation intension. Therefore, customers who set importance on food and brand elements tend to take the brand of food courts into consideration as well; therefore, the maintenance of food quality and strengthening of brand image are mandatory in case of food court operation.

  • PDF

A Qualitative Study on the Adaptation Process of Middle-Aged and Elderly Couples with Retired Husbands (남편의 은퇴 이후 중노년기 부부의 적응과정에 관한 질적 연구)

  • Lee, Ju Yeon;Kim, Deuksung
    • Human Ecology Research
    • /
    • v.53 no.2
    • /
    • pp.179-193
    • /
    • 2015
  • This study examined the retirement adaptation process for middle-aged and elderly couples. Twelve couples who had experienced retirement were recruited by theoretical sampling. Data were collected through in-depth interviews and analyzed through the grounded theory approach of Strauss and Corbin (1998). This study showed the results of 124 concepts, 41 sub-categories and 17 categories indicated through an open coding process. As a paradigm in axial coding, the causal conditions in the adjustment procedures of elderly couples whose spouses are retired were 'retirement preparation,' 'retirement acceptance,' and 'marital satisfaction.' A central phenomenon was 'crisis and conflicts of twilight couples.' The contextual conditions that correspond to this phenomenon were 'psychological separation from adult children,' 'division of household labor,' and 'economic status.' The action/interaction strategies to control the phenomenon were 'recognition of marital relationships,' 'conflicts coping,' 'resolution methods,' and 'self-reflection.' The intervening conditions that facilitate action/interaction strategies were 'attitudes of husbands,' 'mutual awareness of couple,' 'health status,' and 'support systems.' The consequences were 'readaptation of marital relationships,' and 'unresolved conflicts,' and 'trying alone.' This research classified middle-aged and elderly couples' adaptation into three types such as mutual effort, separation & resignation, and conflicts vestige. The findings provide basic information to develop a retirement adaptation program for the middle-aged and elderly.

Determining the Location of Urban Planning Measures for Preventing Debris-Flow Risks: Based on the MCDM Method (MCDM 기법을 이용한 도심지 토사재해 예방을 위한 도시계획적 대책 위치 결정방법 제안)

  • Moon, Yonghee;Lee, Sangeun;Kim, Soyoon;Kim, Myoungsoo
    • Journal of the Korean Society of Safety
    • /
    • v.32 no.5
    • /
    • pp.103-114
    • /
    • 2017
  • The landslide disaster damage has been increased by mountain development, leading to construction of educational facilities, medical facilities, petty industrial facilities, and large housing complexes. Therefore, effective regulation is required as an effort in urban planning solutions. For suggesting specific mitigation strategies on urban landslide, this study aims to define evaluation criteria for urban planning management of debris-flow disaster. AHP (Analytic Hierarchy Process), one of the multiple criterion decision making methods, was utilized in this study. This study makes use of 16 sub-criteria under the framework of hazard, exposure, and vulnerability, and well-planned expert survey measures their weights. The weights are also applied to evaluate each grid in urban space (min $10{\times}10m$) and classify it with red, orange, yellow, or green grade so that areas at higher risk are clearly identified. This study concludes that the suggested method is useful to support a strategies for urban planning management of debris-flow disaster, particularly in a GIS base.

Export Market Attractiveness Analyses of the Heavy Electric Equipment Industry (중전기기산업 수출시장 매력도 분석)

  • Moon, Chang-Kuen
    • International Commerce and Information Review
    • /
    • v.10 no.4
    • /
    • pp.277-298
    • /
    • 2008
  • This study develops the market attractiveness assessment model and draws the strategic target markets and their corresponding exporting strategies through identifying the market positions in the dimensions of market attractiveness scores and market positional strength to achieve the innovative export promotion of Korean heavy electric industry and the resulting improvement and reversal of comparative-disadvantage position. In chapter 2, we analyze the stages of selecting target markets, the constructs and their measure variables of market attractiveness models, and the components and strategic policy implications of directional policy matrix. And in chapter 3, we identify the comparative advantage positions of Korean heavy electric industry in the global market through analyzing its trade structure, trends, balance, ratio-balance, and specialization index by the item and the region respectively. We find that the Asia/Pacific region is the most attractive export market of the Korean heavy electric equipment industry, the following important strategic target markets are the America, MENA, CIS/East Europe Regions in the order of their attractiveness and competitive position dimensions. In the mean time, the sub-Sahara Africa and West Europe region is shown to be the long-run-viewpoint target market requiring the innovation or divest strategies owing to their low attractiveness and the low market share of Korean exports.

  • PDF

A Study on the Development of the Teaching Model for Environmental Education (환경교육을 위한 수업모형 개발에 관한 연구)

  • 최운식;윤성희
    • Hwankyungkyoyuk
    • /
    • v.12 no.1
    • /
    • pp.378-390
    • /
    • 1999
  • The purpose of this study is to investigate what are objects in environmental education and to develop the teaching model for environmental education. The major objects of environmental education is how to teach students who not only take knowledge/skill, but also change their behavior with responsibility for environment. In order to change students' behaviors for environment, Hungerford recommended that teachers have teaching strategies with recognition, evaluation, and adaptation. Also, McCarthy developed teaching model to engage immediate personal meaning, to raise intellectual awareness of a concept, to enhance skills that students can use in their lives, and to foster personal adaptations. Based on the Hungerford's teaching strategies, and Mccarthy's 4MAT system, a teaching model is developed to encourage thinking skill, problem-solving ability, interesting, and participation in the class. The basic steps of the teaching model in this study are experience/recognition, knowledge/skill, evaluation, and adaptation/new experience and 8 sub-steps for instructional methodologies are developed to match of all students' learning style types in a classroom. This model will make it possible to raise the efficiency of instruction, and contribute to changing students who have responsibilities for their environmental behaviors. This model will be supplemented in schools, and applied to developing other instructional issues.

  • PDF

24 Hours Blood Pressure Variation and Related Risk factors (24시간 혈압 변동과 관련 위험 요인)

  • Choi In-Joo;Kim Young-Mi;Lee Hae-Jung
    • Journal of Korean Academy of Fundamentals of Nursing
    • /
    • v.12 no.3
    • /
    • pp.307-316
    • /
    • 2005
  • Purpose: The purpose of this study was to identify 24 hours blood pressure variations among adults over 40 years of age. Method: The participants(50 adults) were recruited from P hospital and B company. The participants were divided into normotensive and hypertensive tendency groups and then sub-divided into non-dipper, dipper, and extreme dipper. The data were collected from April, 2003 to September, 2004 and analyzed using SPSS for Window program. Results: 1) There were significant differences in cardiovascular risk factor, systolic and diastolic blood pressures, and LDH, diet between the normotensive and hypertensive tendency groups. 2) Dippers in both groups showed a marked decrease in blood pressure during the night, but non-dippers in both groups didn't show a marked nocturnal decrease in blood pressure. 3) There were significant differences in heart rate, WHR, BMI, LDH, triglyceride, glucose, affective-oriented coping strategies between dippers and non-dippers. 4) There were significant differences in heart rate, WHR, BMI, LDH, triglyceride, affective-oriented coping strategies between dipper and non-dipper within hypertensive tendency group. Conclusion: Further studies are needed to provide effective intervention in hypertension when applying 24 hour blood pressure monitoring.

  • PDF