• Journal of Korea Water Resources Association
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• v.37 no.3
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• pp.173-184
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• 2004

The objective of this study is to examine the usefulness of climate model simulations (GCM) in Korea water resource management. The methods are based on probabilistic measures of the effectiveness of GCM simulations of an indicator variable for discriminating high versus low regional observations of a target variable. The formulation uses the significance probability of the Kolmogorov-Smirnov test for detecting differences between two variables. AMIP-II(Atmospheric Model Intercomparison Project-II) type GCM simulation done by ECMWF(European Centre for Medium-Range Weather Forecasts) was used for indicator variable and observed mean average precipitation(MAP) values on 7 major river basins were used as target variable. Monte Carlo simulation is used to establish the significance of the estimator values. The results show that GCM simulations done by ECMWF are skillful in discriminating the high from the low of the observed MAP for wet season in all seven basins of Korea, but not enough for dry season.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.322-327
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• 2003

It is important to know the accurate radionuclide inventory of radioactive waste for the reliable management. However, estimation of radionuclide concentrations in drummed radioactive waste is difficult and unreliable because of difficulties of direct detection, high cost, and radiation exposure of sampling personnel. In order to overcome these difficulties, scaling factors (SFs) have been used to assess the activities of radionuclides that could not be directly analyzed. A radionuclide assay system has been operated at KORI site since 1996 and consolidated scaling factor method has played a dominant role in determination of radionuclides concentrations. However, some problems are still remained such as uncertainty of estimated scaling factor values, inaccuracy of analyzed sample values, and disparity between the actual and ideal correlation pairs and the others. Therefore, it needs to improve the accuracy of scaling factor values. The scope of this paper is focused on the improvement of accuracy and representativeness of calculated scaling factor values based on statistical techniques. For the selection of reliable activity determination method, the accuracy of estimated SF values for each activity determination method is compared. From the comparison of each activity determination methods, it is recommended that SF determination method should be changed from the arithmetic mean to the geometrical mean for more reliable estimation of radionuclide activity. Arithmetic mean method and geometric mean method are compared based on the data set in KORI system.

• Korean Journal of Environmental Agriculture
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• v.31 no.1
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• pp.16-23
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• 2012

BACKGROUND: To improve the Daechung reservoir water quality, a quantitative estimation of the delivery load from upper watershed need to be conducted prior to others. To do so, an intensive monitoring is necessary because of the complexity and uncertainty of the delivery load from uppper watershed. However, intensive monitoring need to invest much time, cost, and effort. So, many researcher have developed an equation to estimate the delivery loads. But, relatively little research has been conducted on the applicability of pre-developed equation using other sites. Therefore, the objective of this study was to evaluate application of the equation for BOD, T-N and T-P delivery load. METHODS AND RESULTS: To verify the applicability of the equation, the following equation was used; Delivery loads(kg/day)=generated pollutant loads${\times}(1-{\alpha}){\times}$(daily outflow/${\beta})^{\gamma}$. The equations could be calculated the daily delivery loads of streams without any data of water quality, only with the data of daily runoff of study sites. The equations were applied to Youngdogcheon, Chogangcheon, Bocheongcheon, Sookcheon to examine its applicability using monitoring data. The results showed that the estimated delivery loads were in a good agreement with the observed data and indicated reasonable applicability of the equations. CONCLUSION(s): Overall, the equations were satisfactory in estimation of delivery loads at upper watershed of the Daechung reservoir. Therefore, the equations could be contributed to better water quality management in the Daechung reservoir.

• The Journal of Engineering Geology
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• v.30 no.2
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• pp.131-145
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• 2020

The construction on these flimsy ground, activation of unsymmetrical surcharges, can often cause of the embankment road lateral flow or the destruction of the activities. In this study, the stability of the abutment pile foundation installed on soft ground and its behavior has been evaluated. The behavior of the abutment pile foundation under lateral flow was studied by verifying the behavior and reinforcement effects of the abutment pile foundation of previous studies about horizontal loads acting on the pile due to the lateral flow of the ground by performing finite element analysis. As a result of the consolidation analyses, the undrained cohesion or the strength of the soft ground, was increased by about 1.1 to 1.8 times by the increase in the strength of the soft ground according to the degree of consolidation. It is deemed reasonable to use 3.8 cm of the allowable displacement both economically and constructively, but considering the importance of the structure and the uncertainty of the ground, measurement shall be carried out during construction and thorough safety management of the lateral flow should be done.

• Journal of the Society of Naval Architects of Korea
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• v.51 no.2
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• pp.130-137
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• 2014

As one of the largest shipbuilding company in the world, STX Offshore & Shipbuilding currently developed an inventory managing system for steel-plates, which is applied to their steel stock yard. In a traditional way to manage steel yard, almost every work has been done by manually. The manual steel-plate piling process caused some problems such as process delay due to piling errors and the uncertainty of work plan due to lack of information. To solve these problems, we developed an integrated inventory managing system based on real-time crane tracking system which automatically updates steel-plates' piling status. We built the integrated steel-plate database, developed several programs including steel-plate input program, real-time steel-plate monitoring program and steel-yard management program, and constructed hardware system for tracking magnetic cranes. As a result, a supervisor of steel-yard can manage the inventory of steel-plates efficiently and furthermore plan an efficient piling schedule and crane working schedule.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.3
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• pp.219-230
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• 2017

This study was conducted to predict and evaluate the uncertainty of safety after closure of the second phase surface disposal facility of the Gyeongju intermediate and low level repository in Korea. In this study, four scenarios are developed considering both intact and degraded states of multi-layered covers and disposal containers; also, the fluid flow by a rainfall into the disposal facility is simulated. The rainfall conditions are implemented based on the monthly average data of the past 30 years (1985~2014); the simulation period is 300 years, the management period regulated by institutional provisions. As a result of the evaluation of the basic scenario, in which the integrity of both of the containers and the covers is maintained, it was confirmed that penetration of rainfall does not completely saturate the inside of the disposal facility. It is revealed that the multiple cover layers and concrete containers effectively play the role of barrier against the permeation of rainfall.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.297-308
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• 2020

This study exemines the roles of corporate social activity (CSR) and executive compensation structure on the pricing of seasoned equity offerings (SEOs) with special focus on the role of CSR in reducing the level of information asymmetry between managers and future shareholders of issuing firms through SEOs. This study also investigates the interaction between executive compensation structure and CSR on the discounting of SEOs. We use a sample of 2,102 seasoned equity offerings of U.S. firms with CSR scores from 1995 to 2015 in our OLS fixed effect regression analysis. The results show that issuing firms with high CSR are more likely to expericence a lower degree of the SEO discount. The results also document a positive association between CSR and a high proportion of equity-based compensation of issuing firms' executives. The findings of this paper confirm that CSR attenuates the impact of information asymmetry and the pre-SEO price uncertainty on the pricing of the offers and hence the SEO discount. Furthermore, CSR reinforces the impact of executive firm-related wealth on the discounting of seasoned equity offerings. It appears that firm-related wealth motivates managers to actively engage in reducing information asymmetry activities before SEOs, thereby decreasing the SEO discount.

• Journal of Digital Convergence
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• v.7 no.1
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• pp.157-164
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• 2009

This research focuses on entrepreneurial orientation(EO) of technology spin-offs as they are expected to reduce the gap between their technology and the market. Entrepreneurial orientation is an organizational activity or process that redistributes or combines resources in an innovative way and takes risk to create new values. It helps improve the level of organizational innovation to deal with uncertainty. An empirical study was performed to analyze the EO of spin-offs established by members of university faculties and research institutes in Korea. Antecedent variables to EO are hypothesized to include public policy for university faculty members and researchers at research institutes, the relationship with incubating organizations, and the level of social networking with other firms. The EO and technological performance relationships are also hypothesized. Data from a total of 121 spin-off organizations were collected and a series of multiple regressions were performed. The performance variable included both technological performance, such as the number of newly marketed products and new technology and subjective performance, such as the level of satisfaction with sales amount and profitability. Several important conclusions were drawn from this study. First, while government policy is not related to EO, the policy of a university or a research institute has a significant effect on the level of innovativeness. Second, a high percentage of human resources applied at the incubating organization results in a negative effect on risk taking. The level of cooperation with the incubating organization too is not related to Entrepreneurial Orientation. Third, the intensity of cooperative networking with other firms has a significant effect on risk-taking. Network relationship with government related organizations is not related to Entrepreneurial Orientation. This study analyzes the importance and role of policy of the university and research institute and networking with other firms to improve EO. It also suggests that a high composition of human resources at the incubating organization has a negative relationship with EO.

• Korean Business Review
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• v.11
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• pp.15-38
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• 1998

This study explores the evolution of technical innovation over time. It focuses on sectors of the information technology because this industry can be referred to as one of the most dynamic industries of all times. Following evolutionary theorists, we argue that technological change is gradual and that superior firms and technologies are reward by the' selection' environment. In the initial phase of the industry life cycle, technological change is expected to be radical and uncertainty is high. Over time a product or technology is likely to arise which stands out above all other products or technologies. These so-called 'basic designs' serve as sorts of 'technological guideposts' for further developments in the technology. Once a basic design established, technological progress tends to follow consistent paths or trajectories. The cumulative character of technological progress facilitates a rapid expansion of the boundaries of the technology until the natural limits of the technology are approached and technological progress slows down. Following ecological theories, supply-side developments in the industry are described on the basis of five different organizational types. On the basis of this pattern of market and technological evolution we came up with seven basic propositions.

• KIPS Transactions on Software and Data Engineering
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• v.3 no.9
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• pp.335-340
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• 2014

Crowd Sourcing-based Social App Manufacturing environment, a small app development project by a team of anonymous virtual performed without the constraints of time and space, and manage it for the app development process need to be automated method. Virtual teams with anonymity is a feature of the Social App Manufacturing, is an important factor that increases the uncertainty of whether the completion of the project or reduction in visibility of the progress of the project. In this study, as one of how to manage the project of Social App Manufacturing environment, the impact of risk that can be used to quantitatively measure the impact of the risk of delay in development has on the project also proposes a measurement model. Effects of risk and type of the impact of risks associated with delays in the work schedule also define the characteristic function, measurement model that has been proposed, suggest the degree of influence measurement equation of risk of the project in accordance with the progressive. The advantage of this model, the project manager is able to ensure the visibility of the progress of the project. In addition, identify the project risk of work delays, and to take precautions.