• KDI Journal of Economic Policy
• /
• v.37 no.4
• /
• pp.75-88
• /
• 2015

This study presents a real-time impact evaluation of a human capacity-building health project in Laos, financed by a Korean aid agency and executed jointly by Laotian and Korean higher educational agencies. The project aims to improve the health status of Laotians by enhancing practicing doctors' clinical performance capacity, to be attained by advancing academic achievement at the University of Health Sciences (UHS) in Laos. Therefore, this real-time impact evaluation adopted the difference-in-differences regression analysis method, showing that the project improved the academic achievement of the UHS students who were taught by the project fellowship awardees more, compared to the UHS students who were taught by non-fellowship faculty members. It remains to be evaluated whether these UHS students taught by the project fellowship recipients would also perform better clinically in public hospitals in the future.

• Journal of the Korean Regional Science Association
• /
• v.9 no.2
• /
• pp.27-40
• /
• 1993

Most studies on regional economic impact have utilized employment or employment income data. Recently, a few scholars have noticed the importance of nonemployment income sources in urban economies. Using decennial census data on Arizona towns from 1970 to 1990, this paper first examines the increasing importance of nonempolyment income sources in urban economies and the associations of nonemployment income sources with elderly population and metropolitan location. Then, this paper investigates the impact of nonemployment income on urban growth in the framework of economic base model. The regression results show that the impact of nonemployment income is significant in the increase of nonbasic income and becomes greater over time, and that the impact of transfer over time, and that the impact of transfer income on nonbasic income of transfer income on nonbasic income is stronger in smaller towns and the impact of investment income is stronger in larger towns.

• Proceedings of the Korean Society For Composite Materials Conference
• /
• 2000.04a
• /
• pp.38-42
• /
• 2000

In this study, the low velocity impact behavior of the composite laminates has been described by using 3 dimensional nonlinear finite elements. To describe the geometric nonlinearity due to large deformation, the dynamic contact problem is formulated using the exterior penalty finite element method on the base of Total Lagrangian formulation. The incremental decomposition is introduced, and the converged solution is attained by Newton-Raphson Method. The Newmark's constant-acceleration time integration algorithm is used. To make verification of the finite element program developed in this study, the solution of the nonlinear static problem with occurrence of large deformation is compared with ABAQUS, and the solution of the static contact problem with indentation is compared with the Hertz solution. And, the solution of low velocity impact problem for isotropic material is verificated by comparison with that of LS-DYNA3D. Finally the contact force of impact response from the nonlinear analysis are compared with those from the linear analysis.

• Journal of the Korean Society for Precision Engineering
• /
• v.21 no.1
• /
• pp.189-196
• /
• 2004

A modified generalized particle algorithm, MGPA, was suggested to improve the calculation efficiency of standard SPH Method in numerical analysis of high speed impact behavior. MGPA had a new weight function to reduce computation time. The efficiency of this method was proven through calculation for the sample problems of one dimensional rod impact problem and two dimensional plate impact problem. The MGPA method reduced the calculation error and stress oscillation near the boundaries. The validity of this approach was shown by the comparison with ABAQUS results in two dimensional plate impact problem.

• Computers and Concrete
• /
• v.12 no.1
• /
• pp.37-51
• /
• 2013

The responses of reinforced concrete slabs subject to an impact loading near the ultimate load range are explored. The analysis is carried out on a simply supported rectangular reinforced concrete slab using a nonlinear explicit dynamic procedure and considering three material models: Drucker-Prager, modified Drucker-Prager, and concrete damaged plasticity, available in the commercial finite element software, ABAQUS/Explicit. For comparison purposes, the impact force-time response, steel reinforcement failure, and concrete perforation pattern are verified against the existing experimental results. Also, the effectiveness of mesh density and damage wave propagation are studied independently. It is shown that the presently adopted finite element procedure is able to simulate and predict fairly accurate the behavior of reinforced concrete slab under impact load. More detailed investigations are however demanded for the justification of effects coming from an imperfect projectile orientation as well as the load and structural surface conditions, including the impulsive contacted state, which are inevitable in an actual impact environment.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.12 no.8
• /
• pp.639-647
• /
• 2002

The nonlinear vibration of the thin perforated plate is analyzed in consideration of the V-shaped tension distribution and the effect of wire impact damping. The reduced order FEM model of the tension plate is obtained from dynamic condensation for the mass and stiffness matrices. Tension wire is modeled using the lumped parameter method to effectively describe its contact interactions with the plate. The nonlinear contact-impact model is composed of spring and damper elements, of which parameters are determined from the Hertzian contact theory and the restitution coefficient, respectively. From the evaluation of the computational accuracy and computation time for the deduced impact stiffness and damping coefficient, we determined proper values for the simulation works, accounting for the computational accuracy as well as the computational efficiency. Finally we discussed the results of nonlinear nitration analysis for variations of their design parameters.

• Journal of KSNVE
• /
• v.1 no.2
• /
• pp.115-120
• /
• 1991

The impact hammer is extensively used in experimental modal analysis as a means to provide force over a broad range of frequencies. The hammer mass and the impact head are often changed to achieve a desired impact time duration with its corresponding input frequency spectrum, these mass changes affect the performance and sensitivity of the force transducer employed to measure the impact force. Both a mathematical model describing the effects of impact head and hammer mass on the performance of the force transducer and experimental verification of this model are presented here.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.11 no.1
• /
• pp.211-216
• /
• 2003

A frontal offset impact model Oat can simulate the 40% offset frontal impact into deformable barrier regulated in EU Directive 96/79 EC has been developed. Engine rotation effects are also considered in the model. Distributed 11 masses and characteristics of 23 nonlinear springs comprising the model are determined based on both the stick-model analysis under the general specification of car and the dynamic characteristics of car structure. It is demonstrated that simulated acceleration-time curve for passenger part is in good agreement with test data obtained by NHTSA.

• Journal of Environmental Impact Assessment
• /
• v.6 no.2
• /
• pp.165-180
• /
• 1997

Mitigation measures in EIS are the important factors in the effectiveness of EIS. This paper analyzed the content of mitigation measures described in the 30 EISs selected, using 7 analysis items in order to discover the degree of effectiveness of mitigation measures. 30 EISs used in this study were selected through variance maximization strategy, and the 7 analysis items were; 1) thoroughness of mitigation content, 2) quantification of mitigation content, 3) explicit description of mitigation effect, 4) likelihood of mitigation effect, 5) impacted area of mitigation effect, 6) time frame of mitigation effect, and 7) environmental impact of mitigation measures. The results showed that the effectiveness of mitigation measures in the analyzed EISs was relatively low both in the appropriateness and in the specificity. It was suggested that in order to improve the appropriateness of EIS as a decision making tool, the effect of mitigation measures, as well as the mitigation measures themselves, should be studied and described more thoroughly and specifically.

• The Journal of Asian Finance, Economics and Business
• /
• v.7 no.7
• /
• pp.159-167
• /
• 2020

The study examines the impact of corporate social responsibility (CSR) activity on the firm market value, in particular, market capitalization of tour operators listed on Chinese stock markets. This study employs panel data analysis methods to examine endogeneity concerns in observational data. The balanced panel data includes a total of 1,296 observations with 27 cross-sections of tour operators listed on Chinese stock markets and with 48 time-specific periods from March 2006 to December 2017. The results indicate that CSR activity has a negative impact on the market value of the firm for the concurrent period, but from one-period time lag and afterwards CSR activity has a strong positive impact on the market value and sustains its positive impact on the market value even for a two-period time lag. The findings suggest that the economic effect of CSR activity on the firm market value tends to take some degree of lagged effects to be fully showcased in the market capitalization of tour operators and travel companies listed on Chinese stock markets. The findings suggest that, though CSR activity may carry some financial risk for an immediate short-term, tour operators must put a lot of time and effort into making CSR actions effective.