• Title/Summary/Keyword: State-Society Relations

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CHAOS IN PRODUCTION PLANNING

  • Haghighirad, Farzad;Makui, Ahmad;Ashtiani, Behzad
    • Journal of applied mathematics & informatics
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    • v.26 no.3_4
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    • pp.739-750
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    • 2008
  • A phenomenon which is seen in some of the manufacturing systems and production planning is chaos and the butterfly effect. The butterfly effect points out that in case of the presence of nonlinear relations in system and incorrect estimation of initial values of variables, the error in the estimates of system state will be intensified, and after a while there will be a large distance between available state of system and reality. Using mathematical means and computer simulation, we have tried to demonstrate that in a production system the numerical combination of Cycle Time (CT), Adjustment Time between existing and desired Work In Progress (WIP), and Adjustment Time between current and desired inventory can lead to chaos and butterfly effect in the behavior of the inventory state variable. Our paper concludes with a discussion of a hypothesis that emerged from this research.

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How Language Locates Events

  • 남승호
    • Korean Journal of Cognitive Science
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    • v.10 no.1
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    • pp.45-55
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    • 1999
  • This paper argues that the basic modes of spatial cognition can be best identified in terms of argument/participant location, and shows that natural language uses‘simple’types of semantic denotations to encode spatial cognition, and further notes that spatial expressions should be interpreted not as locating an event/state as a whole but as locating arguments/participants of the event. The ways of locating events/states are identified in terms of argument orientation(AO), Which indicates semantic patterns of linkiarticipant location. and shows that natural langrage uses ng locatives to specific arguments. Four patterns of argument orientation described here reveal substantial modes of spatial cognition. and the AO patterns are mostly determined by the semantic classes of English verbs combining with locative expressions, i.e., by the event type of the predicate. As for the denotational constraint of locatives, the paper concludes that semantic denotations of locative PPs are restricted to the intersecting functions mapping relations to relations.

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Comparative study of constitutive relations implemented in RELAP5 and TRACE - Part II: Wall boiling heat transfer

  • Shin, Sung Gil;Lee, Jeong Ik
    • Nuclear Engineering and Technology
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    • v.54 no.5
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    • pp.1860-1873
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    • 2022
  • Nuclear thermal-hydraulic system analysis codes have been developed to comprehensively model nuclear reactor systems to evaluate the safety of a nuclear reactor system. For analyzing complex systems with finite computational resources, system codes usually solve simplified fluid equations for coarsely discretized control volumes with one-dimensional assumptions and replace source terms in the governing equations with constitutive relations. Wall boiling heat transfer models are regarded as essential models in nuclear safety evaluation among many constitutive relations. The wall boiling heat transfer models of two widely used nuclear system codes, RELAP5 and TRACE, are analyzed in this study. It is first described how wall heat transfer models are composed in the two codes. By utilizing the same method described in Part 1 paper, heat fluxes from the two codes are compared under the same thermal-hydraulic conditions. The significant factors for the differences are identified as well as at which conditions the non-negligible difference occurs. Steady-state simulations with both codes are also conducted to confirm how the difference in wall heat transfer models impacts the simulation results.

Proposal of Stress-Strain Relations Considering Confined Effects for Various Composite Columns (합성형태에 따른 콘크리트 구속효과를 고려한 응력-변형률 관계식의 제안)

  • Park, Kuk Dong;Hwang, Won Sub;Yoon, Hee Taek;Sun, Woo Hyun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.3A
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    • pp.265-275
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    • 2010
  • Concrete filled steel tube and concrete encased steel tube columns are expected to have confined effects of concrete by steel and reinforced effects of local buckling by concrete. On the basis of confined state concrete models of previous researches, stress-strain and load-displacement relations of RC, CFT and CET columns are analyzed by steel ratio. After comparing analysis results with experimental results, Modified stress-strain relations are derived through evaluation the influence upon confined effects of concrete in each cases. Also, the modified stress-strain models are carried out to be compared with specified strength of various countries.

A Few Problems for the Intellectual Development of Students in High Schools and Community Colleges

  • Mulyukov, Rustem
    • Research in Mathematical Education
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    • v.14 no.3
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    • pp.211-218
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    • 2010
  • It is a truism that mathematics is about relations (cf. [Halford, G. S. (1999). The properties of representations used in higher cognitive processes: Developmental implications. In: Sigel, I. E. (Ed.), The Development of Mental Representation: Theories and Applications (pp. 147-168). Mahwah, New Jersey: Erlbaum]). In this article we are considering few problems related to the Viviani's and Routh's Theorems. All Problems are connected by the relation which exists between the distances of the point inside the triangle to it sides. We show how reasoning about the relations could lead the student's problem solving process and give easy to understand solutions of the problems. Among the problems being considered are the proof of the Converse to Viviani's Theorem, the formulas for areas of all figures formed by the sides of triangle and its cevians.

The Method of Creating the Road Network Database for an Integrated Road Management System (도로관리 종합정보 시스템을 위한 도로망 데이타베이스 구축방안)

  • 김충평;이강원;김경희
    • Spatial Information Research
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    • v.3 no.1
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    • pp.55-63
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    • 1995
  • The database design, which logically sets the base structure and orga¬nization of the database, is performed by considering the users requirement, the relations between various data, and the relations between data and application field.The road network data must be created to have geometrical topological structure, because various data elements are needed to recognize the state of each section and to relate between data element. In this study, we propose a method of creating the road network database for an integrated road management system.

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Predictive Factors of Health promotion behaviors of Industrial Shift Workers (산업장 교대근무 근로자의 건강증진행위 예측요인)

  • Kim, Young-Mi
    • Korean Journal of Occupational Health Nursing
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    • v.11 no.1
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    • pp.13-30
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    • 2002
  • Industrial shift workers feels suffer mental stresses which are caused by unfamiliar day sleep, noisy environment, sleeping disorder by bright light, unusual contacts with family, difficulty in meeting with friends or having formal social meetings and other social limitations such as the use of transportation. Such stresses influence health of the workers negatively. Thus the health promotion policy for shift workers should be made considering the workers' ways of living and shift work specially. This study attempted to provide basic information for development of the health promotion program for industrial shift workers by examining predictive factors influencing health promotion behaviors of those workers. In designing the study, three power generation plants located in Pusan and south Kyungsang province were randomly selected and therefrom 280 workers at central control, boiler and turbine rooms and environmental chemistry parts whose processes require shift works were sampled as subjects of the study. Data were collected two times from September 17 to October 8, 1999 using questionnaires with helps of safety and health managers of the plants. The questionnaires were distributed through mails or direct visits. Means for the study included the measurement tool of health promotion behavior provided by Park(1995), the tool of self-efficacy measurement by Suh(1995), the tool of internal locus of control measurement by Oh(1987), the measurement tool of perceived health state by Park(1995) and the tool of social support measurement by Paek(1995). The collected data were analyzed using SPSS program. Controlling factors of the subjects were evaluated in terms of frequency and percentage ratio Perceived factors and health promotion behaviors of the subjects were done so in terms of mean and standard deviation, and average mark and standard deviation, respectively. Relations between controlling and perceived factors were analyzed using t-test and ANOVA and those between perceived factors and the performance of health promotion behaviors, using Pearson's Correlation Coefficient. The performance of health promotion behaviors was tested using t-test, ANOVA and post multi-comparison (Scheffe test). Predictive factors of health promotion behavior were examined through the Stepwise Multiple Regression Analysis. Results of the study are summarized as follows. 1. The performance of health promotion behaviors by the subjects was evaluated as having the value of mean, $161.27{\pm}26.73$ points(min.:60, max.:240) and average mark, $2.68{\pm}0.44$ points(min.:1, max.:4). When the performance was analyzed according to related aspects, it showed the highest level in harmonious relation with average mark, $3.15{\pm}.56$ points, followed by hygienic life($3.03{\pm}.55$), self-realization ($2.84{\pm}.55$), emotional support($2.73{\pm}.61$), regular meals($2.71{\pm}.76$), self-control($2.62{\pm}.63$), health diet($2.62{\pm}.56$), rest and sleep($2.60{\pm}.59$), exercise and activity($2.53{\pm}.57$), diet control($2.52{\pm}.56$) and special health management($2.06{\pm}.65$). 2. In relations between perceived factors of the subjects(self-efficacy, internal locus of control, perceived health state) and the performance of health promotion behaviors, the performance was found having significantly pure relations with self-efficacy (r=.524, P=.000), internal locus of control (r=.225, P=.000) and perceived health state(r=.244, P=.000). The higher each evaluated point of the three factors was, the higher the performance was in level. 3. When relations between the controlling factors(demography-based social, health-related, job-related and human relations characteristics) and the performance of health promotion behaviors were analyzed, the performance showed significant differences according to marital status (t=2.09, P= .03), religion(F=3.93, P= .00) and participation in religious activities (F=8.10, P= .00) out of demography-based characteristics, medical examination results (F=7.20, P= .00) and methods of the collection of health knowledge and information(F=3.41, P= .01) and methods of desired health education(F=3.41, P= .01) out of health-related characteristics, detrimental factors perception(F=4.49, P= .01) and job satisfaction(F=8.41, P= .00) out of job-related characteristics and social support(F=14.69, P= .00) out of human relations characteristics. 4. The factor which is a variable predicting best the performance of health promotion behaviors by the subjects was the self-efficacy accounting for 27.4% of the prediction, followed by participation in religious activities, social support, job satisfaction, received health state and internal locus of control in order all of which totally account for 41.0%. In conclusion, the predictive factor which most influence the performance of health promotion behaviors by shift workers was self-efficacy. To promote the sense, therefore, it is necessary to develop the nursing intervention program considering predictive factors as variables identified in this study. Further industrial nurses should play their roles actively to help shift workers increase their capability of self-management of health.

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Reservoir Trophic State and Empirical Model Analysis, Based on Nutrients, Transparency, and Chlorophyll-${\alpha}$ Along with Their Relations Among the Parameters (영양염류, 투명도 및 엽록소를 이용한 인공호 영양상태, 경험적 모델 분석 및 변수들 간의 상호관계)

  • An, Kwang-Guk;Kim, Jae-Kyeng;Lee, Sang-Jae
    • Korean Journal of Environmental Biology
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    • v.26 no.3
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    • pp.252-263
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    • 2008
  • The purpose of this study was to determine trophic state, based on nutrients (TN, TP), transparency (SD), and chlorophyll-${\alpha}$ (Chl) and identify their empirical relations of TN-Chl, TP-Chl and Chl-SD depending on the dataset used along with dynamics of conductivity and suspended solids. Analysis of trophic states showed that more than half of 36 reservoirs were judged as eutrophic-hypertrophic conditions depending on the trophic variables. Seasonal values of TP varied by nearly 500% and showed greater in August than any other months. In contrast, TN varied within less than 90% and all monthly mean values of TN were never fall less than 1.2 mg L$^{-1}$ indicating low seasonal variations and high ambient concentrations (eutrophic-hypertrophic state). Analysis of empirical relations in the trophic variables showed that transparency had greater functional relations with Chl (R$^2$=0.31, p<0.001) than TP (R$^2$=0.15, p<0.001) and TN (R$^2$=0.20, p<0.001). Ratios of TN : TP in the ambient water indicated that most reservoirs showed a potential phosphorous limitation on the algal growth. Thus, algal biomass, based on Chl values, was more regulated by phosphorous than nitrogen. Analysis of linear regression model, based on log-transformed annual mean values, showed that only 30% in the variation of Chl was explained by TP (R$^2$=0.295, p=0.001, n=36) and 15% by TN (R$^2$=0.151, p=0.019, n=36). However, linear regression model, based on individual system, showed that Chl-TP model had strong positive relations (R$^2$=0.62, p=0.002, n=12), whereas the model had no any relations (p=0.892, n=12). Overall, our data suggested that averaging effect in the empirical model developments may influence the significance in the statistical analysis.

Length-Weight Relations and Condition Factor (K) of Zacco platypus Along Trophic Gradients in Reservoir Ecosystems (인공호의 부영양화에 따른 피라미(Zacco platypus) 개체군의 전장-체중 관계 및 비만도 지수)

  • Ko, Dae-Geun;Han, Jeong-Ho;An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.45 no.2
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    • pp.174-189
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    • 2012
  • The objective of this study was to determine the weight-length relations and condition factor (K) of Zacco platypus, along the trophic gradients from oligotrophic to eutrophic state in six reservoir ecosystems ($B_aR$, $Y_yR$, $J_yR$, $G_pR$, $Y_dR$, and $M_sR$), during 2008~2010. The species was selected as a sentinel species for the study, due to its wide distribution and wide trophic gradient. The analysis of trophic state index (TSI), based on total phosphorus (TP) and chlorophyll-a (Chl-a), indicated that reservoirs of $Y_yR$ and $B_aR$ were classified as to be in an oligotrophic state (30~40), the $J_yR$ and $G_pR$ as mesotrophic (40~50), and the $Y_dR$ and $M_sR$ as eutrophic state (50~70). Total 47 species and 26,226 individuals were sampled from 6 reservoirs and sensitive species dominated in the oligotrophic reservoirs ($Y_yR$ and $B_aR$). In the mean time, the tolerant speciesdominated the community in the mesotrophic ($J_yR$ and $G_pR$) and eutrophic ($Y_dR$ and $M_sR$) reservoirs. Regression analysis of body weight, against the total length, indicated that the regression coefficient (b value) was lower in the oligotrophic reservoir (2.77~2.79) than the mesotrophic (3.07~3.17) and eutrophic reservoirs (3.15~ 3.21). This result suggests that the population growth rate Zacco platypus reflected the trophic gradients of the reservoirs. The analysis of condition factor (K) against the total length showed positive slopes (b>3.0) in mesotrophic and eutrophic reservoirs, and a negative slope (b<3.0) in oligotrophic reservoir. The variation of the regression slope of "b" in Z. platypus was accounted for 79.7% [$b=0.012{\times}TSI(TP)+2.395$, p=0.017] by the variation of TSI (TP) and 82.2% [$b=0.013{\times}TSI(Chl-a)+2.36$, p=0.013] by the variation of TSI (Chl-a). The proportion of DELT abnormality increased as the trophic state increases in the reservoirs. The overall data suggest that the growth of the fish populations, based on the length-weight relations and condition factor, reflected the trophic state of nutrient and phytoplankton biomass of the reservoir waters. Thus, in spite of the tolerant characteristics of Z. platypus, hypertrophic states might negatively affect the health of the population.

Study on Suicidal Ideation and Associated Factors in Rural Elderly (농촌 노인의 자살의도와 관련요인)

  • Song, Min Sun;Kim, Nam Cho
    • Journal of Korean Public Health Nursing
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    • v.28 no.1
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    • pp.127-137
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    • 2014
  • Purpose: The purpose of this study was to investigate differences in suicidal ideation according to general characteristics, and to identify the associated factors of suicidal ideation in rural elderly. Method: We surveyed 168 elderly people using structured questionnaires from March through April, 2013. Data analy was performed using descriptive statistics, ${\chi}^2$ test, Fisher's Exact test, and multiple regression using the SPSS program. Results: Significantly differences in suicidal ideation score were observed according to drinking state(p=.036), sleep state(p=.013), health state(p=.020), and stress state(p=.049). The associated factors identified in this study significantly explained 13.2% of suicidal ideation. Smoking and sleep state were the most significant factors of suicidal ideation. Conclusion: Based on these results, development of programs for promotion of psychological health in order to reduce suicide rates of the elderly is urgent. In particular when focusing on relations between sleep disturbance and suicide, it is considered that nursing intervention will be required to promote quality of sleep in clinical practices and communities.