• Water for future
• /
• v.28 no.6
• /
• pp.107-118
• /
• 1995

Mathematical models have been developed in which storage-relaease processes of pollutants are modeled to explain storage effect of variations of flow and channel geometry on mixing and transport of polluted releases in natural channels including low flow conditions. The models were tested by using the laboratory dispersion data. Comparisons between concentration-time curves predicted by using the proposed model incorporating two different submodels show that Storage-Diffusion Model seems to be superior in explaining physical processes inside the storage zone to the Storage-Exchange Model even though accuracies of simulation results by two models are about the same. The proposed model shows significant improvement over the conventional one-dimensional dispersion model in predicting natural mixing processes in open channels.

• Wind and Structures
• /
• v.19 no.6
• /
• pp.623-647
• /
• 2014

In this paper, a probability distribution which is consistent with the observed phenomenon at the roof corner and, also on other portions of the roof, of a low-rise building is proposed. The model is consistent with the choice of probability density function suggested by the statistical thermodynamics of open systems and turbulence modelling in fluid mechanics. After presenting the justification based on physical phenomenon and based on statistical arguments, the fit of alpha-stable distribution for prediction of extreme negative wind pressure coefficients is explored. The predictions are compared with those actually observed during wind tunnel experiments (using wind tunnel experimental data obtained from the aerodynamic database of Tokyo Polytechnic University), and those predicted by using Gumbel minimum and Hermite polynomial model. The predictions are also compared with those estimated using a recently proposed non-parametric model in regions where stability criterion (in skewness-kurtosis space) is satisfied. From the comparisons, it is noted that the proposed model can be used to estimate the extreme peak negative wind pressure coefficients. The model has an advantage that it is consistent with the physical processes proposed in the literature for explaining large fluctuations at the roof corners.

• Knowledge Management Research
• /
• v.11 no.5
• /
• pp.1-23
• /
• 2010

In order to provide a better understanding about the phenomenon of KM assimilation, this study attempts to conceptually develop and empirically compare two different models: (1) the first model, which considers the KM process as the flow of knowledge that plays an intervening role between knowledge stocks (i.e., knowledge worker, technical knowledge infrastructure, external knowledge linkage, knowledge strategy, and internal knowledge climate) and the level of KM assimilation; and (2) the second model is a simple direct effect formulation without any distinction between knowledge stock and flow. These two models were then tested and compared using the responses of 187 Korean organizations that had already implemented enterprise-wide KM systems. The findings indicate that the two models are useful in explaining successful KM assimilation. However, the first causal model with the distinction between knowledge stock and flow assesses the effectiveness of KM more accurately than the second model without the distinction. Interestingly, the KM process was shown to be the most critical factor for the proliferation of KM activities across an organization. The findings of this study are expected to serve not only as early groundwork for researchers hoping to understand KM and its effective assimilation in organizations, but should also provide practitioners with guidelines as to how they can enhance their KM assimilation level so as to improve their organizational performance.

• Korean Journal of Adult Nursing
• /
• v.20 no.4
• /
• pp.641-651
• /
• 2008

Purpose: this study was to develop and test the structural model that explains husband and wife compatibility and family health of married middle-aged. A hypothetical model explaining husband and wife compatibility and family health based on literature reviews. There were three theoretical variables and twelve observed variables in hypothetical model. Methods: Data collection was carried out May through July 2005. Data were collected by self-reporting questionnaires from 854 married middle-aged who lived in Seoul, Busan, Daegu, Kyungnam, Kyungpook. Collected data was analyzed using SPSS/WIN 12.0 for descriptive statistics, Pearson Correlation coefficient, and Kolmogorov-Smirnov analysis. Results: LISREL program was used to find the best fit normal which assumes causal relationship among variables. This model was to be good fitting and parsimonious to measure husband and wife compatibility and family health of married middle-aged. Conclusion: Differentiation of self and husband and wife compatibility predicted level of family health. Therefore, a family health improvement program needs to include these two variables.

• Journal of the Society of Naval Architects of Korea
• /
• v.51 no.3
• /
• pp.179-183
• /
• 2014

The fluid loading effect has been investigated for the shipboard equipment foundation mobility with finite element model. For the purpose, two kinds of finite element models for 60m class ship have been developed: global and local model. The former is for low frequency range and the latter for middle frequency range. These finite element models contain added mass explaining fluid loading effect. Added mass has been implemented with virtual mass matrix derived from Laplace equation governing fluid surrounding ship hull. The mobility assessment result for diesel generator foundation of the objective model shows that the fluid loading effect should be considered, especially in low frequency range, to more accurately assess shipboard equipment foundation mobility.

• Geomechanics and Engineering
• /
• v.14 no.3
• /
• pp.225-231
• /
• 2018

In this paper, in order to explain the splitting of cylindrical rock specimen under uniaxial loading, cracks in cylindrical rock specimen are divided into two kinds, the longitudinal crack and the slanting crack. Mechanical behavior of the rock is described by elastic-brittle-plastic model and splitting is assumed to suddenly occur when the uniaxial compressive strength is reached. Expression of the stresses induced by the longitudinal crack in direction perpendicular to the major axis of the crack is deduced by using the Maxwell model. Results show that the induced stress is tensile and can be greater than the tensile strength even before the uniaxial compressive strength is reached. By using the Inglis's formula and simplifying the cracks as slender ellipse, the above conclusions that drawn by using the Maxwell model are confirmed. Compared to shearing fracture, energy consumption of splitting seems to be less, and splitting is most likely to occur when the uniaxial loading is great and quick. Besides, explaining the rock core disking occurred under the fast axial unloading by using the Maxwell model may be helpful for understanding that rock core disking is fundamentally a tensile failure phenomenon.

• Asia pacific journal of information systems
• /
• v.15 no.3
• /
• pp.91-109
• /
• 2005

According to traditional theories of information systems, one of the reasons for using information technology is that users believe it to be helpful or useful for what they want to do, which is called extrinsic motivation. However, in addition to extrinsic motivation, there are other reasons for using it such as enjoying or playing with information technology itself, called intrinsic motivation, and just others around users, called social influence. The objective of this study is to provide a research model for using information technology considering intrinsic and extrinsic motivation, and social influence. For validation of this model, we survey the users of 'Minihompy' since it is one of the most popular blog services in Korea and there are relatively clear extrinsic and intrinsic motivation, and social influence respectively in using it. By analysing 549 valid samples by Partial Least Square(PLS), we show the suggested research model to be a valid one. That is, all hypotheses we suggested turn out to be statistically significant and $R^2$ of the dependent variable, the intention of use, explaining by the model to be higher than 40%. In addition to validation of the research model, it is found that intrinsic motivation may be more important than extrinsic motivation and social influence in using information technology.

• Journal of Korean Public Health Nursing
• /
• v.37 no.2
• /
• pp.275-289
• /
• 2023

Purpose: This study developed a structural model for explaining and predicting terminal care performance in long-term care hospital nurses. The model was based on the stress integration model of Ivancevich and Matteson(1980) and the results of previous studies. Method: Data was obtained from August to September 2022 from 267 nurses in 13 long-term care hospitals in G-do. Results: Results of model verification for this study, revealed that factors directly affecting the terminal care performance of long-term care hospital nurses were nursing work environment(β=0.43, p<0.001), death anxiety(β=-0.29, p<0.001), and terminal care stress(β=0.22, p=0.003). However, the attitude toward nursing care of dying(β=0.07, p=0.287) had no effect on the terminal care performance. Conclusion: The results of this study, confirmed the necessity of improving an individual's perceived nursing work environment, continuous education related to terminal care to reduce death anxiety, and an interventional approach for enhancing terminal care performance.

• Fourth Industrial Review
• /
• v.3 no.2
• /
• pp.1-10
• /
• 2023

Purpose - The main purpose of the paper is to examine the variables affecting carbon emissions in different nations around the world. Research design, data, and methodology - To measure its impact on carbon emissions, secondary data has data of the top 50 Countries have been taken. The stochastic Impacts by Regression on Population, Affluence, and Technology (STIRPAT) model have been used to quantify the factors that affect carbon emissions. A modified version using Industry 4.0 and region in fundamental STIRPAT model has been applied with the ordinary least square approach. The outcome has been measured using both the basic and extended STIRPAT models. Result - Technology found a positive determinant as well as statistically significant at the alpha level of 0.001models indicating that technological innovation helps reduce carbon emissions. In total, 4 models have been derived to test the best fit and find the highest explaining capacity of variance. Model 3 is found best fit in explanatory power with the highest adjusted R2 (97.95%). Conclusion - It can be concluded that the selected explanatory variables population and Industry 4.0 are found important indicators and causal factors for carbon emission and found constant with all four models for total CO2 and Co2 per capita.

• Agribusiness and Information Management
• /
• v.5 no.1
• /
• pp.20-30
• /
• 2013

This paper presents a model explaining industrywide information systems (IS) integration in the agri-industry. Using a theoretical frame of value configuration analysis and IS integration extent we study 15 organizations. We find that product sensitivity, continuous production, value chain captains, and value creation logic explain the industry-wide IS integration. Incompatible value creation logic among stakeholders and the lack of presence of "value chain captains" - powerful actors dominating the entire industry - has and negative impact on industry-wide integration. On the other hand, product sensitivity and continuous production process led to higher levels of integration.