• Journal of Environmental Impact Assessment
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• v.12 no.3
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• pp.199-209
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• 2003

The withdrawal method for protecting the uncontaminated part from the spread of contaminants was suggested by a simultaneous equation. The formulation of them is based upon the build up of the ridge part between the contaminated and uncontaminated parts that resulted from the efficient use of barrier wells. The quality in the withdrawn groundwater depends upon the heads at wells no. 5 and 6. The determination of pumping rates and qualities with changing the heads at wells no. 5 and 6 should be given by considering the demand for water use and the capacity and cost for removing the contained contaminants. The results of this study should be used in taking a plan for supplying water use as well as preventing the spread of contaminants from some known contaminated sources.

• The Korean Journal of Applied Statistics
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• v.18 no.1
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• pp.147-158
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• 2005

Most of the statistical models that real data can be applicable are static in nature, and thus it is not possible to analyze the effect of variations in the real world over time. Usual specification of the models does not produce the length and the time path of the effect even if the effect of an exogenous variation continues for periods of time. In this study, deriving the dynamic inherence from the static structure of the linear model for better utilization, we attempt to apply actual data to compare and analyze the long-run effect of variations in the market variables between the related markets by formulating a simultaneous equation system. Accordingly, it is proved to be possible to obtain efficient analytical results and to derive various useful implications.

• Journal for History of Mathematics
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• v.24 no.1
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• pp.15-29
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• 2011

This study was carrying out research on the geometry of Sulbas${\={u}}$tras as parts of looking for historical roots of oriental mathematics, The Sulbas${\={u}}$tras(rope's rules), a collection of Hindu religious documents, was written between Vedic period(BC 1500~600). The geometry of Sulbas${\={u}}$tras in ancient India was studied to construct or design for sacrificial rite and fire altars. The Sulbas${\={u}}$tras contains not only geometrical contents such as simple statement of plane figures, geometrical constructions for combination and transformation of areas, but also algebraic contents such as Pythagoras theorem and Pythagorean triples, irrational number, simultaneous indeterminate equation and so on. This paper examined the key features of the geometry of Sulbas${\={u}}$tras and the geometry of Sulbas${\={u}}$tras for the construction of the sacrificial rite and the fire altars. Also, in this study we compared geometry developments in ancient India with one of the other ancient civilizations.

• Asia-Pacific Journal of Business
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• v.12 no.3
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• pp.175-192
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• 2021

Purpose - In this study, we investigate the effects of government environmental subsidies and the globalization Chinese firms on their profitability using return on assets (ROA). Design/methodology/approach - In this study, a merged data including accounting, financial market, subsidization of the Chinese governments, local and the central, and export activities of 19,563 year-firms, for those listed on Shanghai Stock and Shenzhen Stock Exchange for 11 years from 2008 to 2018 is used. We collect subsidy data from RESSET database and financial data from CSMAR database. Then, we empirically test the test hypotheses using fixed effects models (FEM) separately and in a simultaneous equation model (SEM). Findings - Firstly, the globalization of Chinese firms has a negative impact on their profitability for some years after the year. Secondly, environmental subsidies just like other subsidies have ameliorating effects on financial performance for global firms. Such effects have lasted some years. Thirdly, environmental investments have a mostly negative impact on short- and long-term profitability for global firms. Lastly, the government's environmental subsidies in China have a positive effect on their profitability for both global and domestic firms. Research implications or Originality - We can infer that environmental investments with the help of the governmental subsidies can help Chinese firms deploy global strategies to expand markets to surpass competitors in the long run despite worsening profitability in global markets in the short run.

• Korean Journal of Social Welfare Studies
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• v.41 no.1
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• pp.345-375
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• 2010

This study is aimed at investigating the effects of school violence on adolescent depression and suicide, where both the mediating effects of resilency and the gender diffences are considered. The data, collected from 664 high and middle school students, were examined by the statistics software SPSS 17.0 and AMOS 17.0, in which descriptive statistics, factor analysis, structural equation model analysis, and multi-group simultaneous analysis are utilized. As a result, it is shown from the structural equation modeling that school violence have positive effects on depression and suicide, but negative effects on family and academic resiliency. Both ego and family resiliency act as protective factors, negatively affecting the depression. In addition, the family resiliency had negative effects on suicide. The results of multi-group simultaneous analysis imply that school violence have different effects on suicide and family resiliency respectively, depending on gender differences. Female adolescents are affected more strongly than male adolescents.

• Journal of Soil and Groundwater Environment
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• v.6 no.2
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• pp.69-81
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• 2001

The constitutive relation among capillary pressure, saturation and relative permeability should be predetermined in order to simulate immiscible water-gas flow in porous media. The relation between saturation and relative permeability becomes more important when the capillary force can be disregarded and viscous friction force governs the flow. In this study, a 2-dimensional finite difference numerical model was developed, in which the variation of viscosity with pressure and that of relative permeability with water saturation can be treated. Seven cases of parallel plate tests were performed in order to obtain the characteristic equation of relative permeability which would be used in. the developed numerical model. It was not possible, however, to match the curves of relative permeability from the plate tests with the existing emperical models. Consequently a logistic equation was proposed as a new emperical model. As this model was composed of the parameter involving aperture size, any aperture size of fracture can be applied to the model. For the purpose of verification, the characteristic equation of relative permeability was applied to the developed numerical model and the computed results were compared with those of plate test. As a result of application of numerical model, in order to check the field applicability, to single fracture surrounding an underground storage cavern, the simultaneous flow of water and propane gas was able to be simulated properly by the model.

• Composites Research
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• v.29 no.3
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• pp.91-97
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• 2016

In this paper, impulse-momentum theory was coupled to a constitutive equation both for implementing quasi-static and impact characteristics of EPP (Expanded polypropylene). Also, parameters which have physical meanings were expressed as functions of relative density. Simultaneous nonlinear Newton-Raphson method was applied to find the proper values for parameters in the constitutive equation along with quasi-static test data. Results from the impulse-momentum theory coupled constitutive equation showed good agreement with experimental data and the potential to be applied to different material type polymeric foam.

• Structural Engineering and Mechanics
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• v.12 no.6
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• pp.657-668
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• 2001

Fiber reinforced cementitious composites are nowadays widely applied in civil engineering. The postcracking performance of this material depends on the interaction between a steel fiber, which is obliquely across a crack, and its surrounding matrix. While the partly debonded steel fiber is subjected to pulling out from the matrix and simultaneously subjected to transverse force, it may be modelled as a Bernoulli-Euler beam partly supported on an elastic foundation with non-linearly varying modulus. The fiber bridging the crack may be cut into two parts to simplify the problem (Leung and Li 1992). To obtain the transverse displacement at the cut end of the fiber (Fig. 1), it is convenient to directly solve the corresponding differential equation. At the first glance, it is a classical beam on foundation problem. However, the differential equation is not analytically solvable due to the non-linear distribution of the foundation stiffness. Moreover, since the second order deformation effect is included, the boundary conditions become complex and hence conventional numerical tools such as the spline or difference methods may not be sufficient. In this study, moment equilibrium is the basis for formulation of the fundamental differential equation for the beam (Timoshenko 1956). For the cantilever part of the beam, direct integration is performed. For the non-linearly supported part, a transformation is carried out to reduce the higher order differential equation into one order simultaneous equations. The Runge-Kutta technique is employed for the solution within the boundary domain. Finally, multi-dimensional optimization approaches are carefully tested and applied to find the boundary values that are of interest. The numerical solution procedure is demonstrated to be stable and convergent.

• The Korean Journal of Applied Statistics
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• v.27 no.5
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• pp.797-808
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• 2014

It is increasingly interested in investigating the relationships and the dynamic characteristics of variations among high class corporate values. This study formulates a statistical model of simultaneous equation system to examine the relationships among variations of stock returns for each class of corporate governance structure and to analyze the dynamic patterns of their long-run adjustment processes. Changes in stock returns for each class of corporate governance by an exogenous shock are found to have common structural features of slow adjustments to the long-run equilibriums.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.650-655
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• 2012

This purposes of this study were to explain consumer attitudes and purchasing behaviors towards agricultural products using a social network service and to determine the influencing factors such as experience, technology ability, innovation, self-efficacy, perception of usefulness, perception of trust, attitude, purpose of purchase and individual characteristics on them. We analyzed the survey data set, using the 'logit model', 'simultaneous equation model', and 'LISREL-Type model' In this study, the results obtained are summarized as follows. The result for the comprehensive statement of "Trust" was the biggest influence on the purchase agricultural products using the social network service. Therefore, in order to expand agricultural e-commerce using SNS, trust should be to the fore of marketing and publicity campaigns, in order to promote and stabilize the market.