• Bulletin of the Korean Chemical Society
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• v.27 no.10
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• pp.1531-1536
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• 2006

Microsomal prostaglandin $E_2$ synthase (mPGES-1) is an enzyme that is associated with inflammation, pain, fever and cancer. Hologram quantitative structure activity relationship (HQSAR) was conducted on the series of MK-886 compounds acting as mPGES-1 inhibitors. A training set with 24 compounds was used to establish the HQSAR model. The best model was chosen based on the cross-validated correlation coefficient ($q^2$=0.884) and the correlation coefficient($r^2$=0.976). The model was utilized to predict the activity of the eight-test set of compounds giving the predictive $r^2$ value of 0.845. The descriptors of the model are based on fragment distinction (atoms, bond and connectivity) and fragment size (2-5 atoms). The atomic contribution maps generated from HQSAR were useful in identifying the important structural features responsible for the inhibitory activity of MK-886 inhibitors. Based on the generated model, the presence of hydrophobic biphenyl group seems to enhance inhibition of mPGES-1 that is in agreement with the previous experiments. In addition, it seems important for a halogen to be substituted to the biphenyl ring and for an acyl group to be attached to the indole moiety for enhanced activity.

• Asia pacific journal of information systems
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• v.6 no.2
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• pp.201-220
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• 1996

The effects of information technology on people and society, while being profusely laid out in academic and popular literature, are largely anecdotal, fragmented, and speculative, not adding up to a consistent theory of IT impact. This is attributed to a lack of a proper research model that guides and integrates the research. This paper examines several dimensions of the IT impact research that characterize and distinguish the research and develops a conceptual model of the IT impact research. Three dimensions are examined - the search domain, the concept of organization, and the level of analysis. The dimensions are combined to produce several conceptual domains, each with differing issues and characteristics for research, that constitute the IT impact research. A model of the IT impact research is developed which proposes a series of transition among the search domains. At the end, the implications of the research model are discussed.

• Water for future
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• v.12 no.1
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• pp.49-55
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• 1979

A series of hydraulic model tests have been conducted for a Parshall flume which was designed for streamflow measurements of two experimental basins in Banwol New Industrial Town. the purpose being to study the effect of urbanizations on the watershed hydrology. The model scale was determined based on the 100-year flood discharge of the basins considering the discharge cf the basins considering the discharge capacity of the hydraulic laboratory where the whole tests were conducted. The calibration equations for depth-discharge relations were derived by analyzing the model test data and were compared with those of Parshall's work. The discharge calibration for the prototype flume, which is to be constructed at the outlets of the experimental basins, was obtained through the analysis of data converted from the model test data by the laws of similarity.

• IE interfaces
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• v.24 no.2
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• pp.128-138
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• 2011

This research proposes a resource allocation model of Data QC (Quality Control) activities using COQ (Cost of Quality). The model has been developed based on a series of research efforts such as COQ classifications, weight determination of Data QC activities, and an aggregation approach between COQ and Data QC activities. In the first stage of this research, COQ was divided into the four typical classifications (prevention costs, appraisal costs, internal failure costs and external failure costs) through the opinions from five professionals in Data QC. In the second stage, the weights of Data QC activities were elicited from the field professionals. An aggregation model between COQ and Data QC activities has been then proposed to help the practitioners make a resource allocation strategy. DEA (Data Envelopment Analysis) was utilized for locating efficient decision points. The proposed resource allocation model has been validated using the case of Korea national defense information system. This research is unique in that it applies the concept of COQ to the data management for the first time and that it demonstrates a possible contribution to a real world case for budget allocation of national defense information.

• Journal of Korean Institute of Industrial Engineers
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• v.27 no.3
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• pp.239-249
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• 2001

Competitive coevolution models, often called host-parasite models, are searching models that imitate the biological coevolution that is a series of reciprocal changes in two competing species. The models are known to be an effective method of solving complex and dynamic problems such as game problems, neural network design problems and constraint satisfaction problems. However, previous models consider only ectoparasites that live on the outside of the host when designing the models, not considering endoparasites that live on the inside of the host. This has a limitation to exploiting some information. In this paper, we develop an artificial adaptation model simulating the process in which hosts coevolve with both ectoparasites and endoparasites. In the model, the endoparasites play important roles as follows. By means of them, we can keep the history on results of previous competition between hosts and parasites, and use endogeneous fitness, not exogeneous. Extensive experiments are carried out to show the coevolution phenomenon and to verify the performance of the proposed model. Nim game problems and neural network problems are used as test-bed problems. The results are reported in this paper.

• Ocean and Polar Research
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• v.35 no.2
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• pp.135-146
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• 2013

This study investigates the characteristic of the Tsushima Warm Current from an assimilated high resolution global ocean prediction model, $1/12^{\circ}$ Global HYbrid Coordiate Ocean Model (HYCOM). The model results were verified through a comparison with current measurements obtained by acoustic Doppler current profiler (ADCP) mounted on the passenger ferryboat between Busan, Korea, and Hakata, Japan. The annual mean transport of the Tsushima Warm Current was 2.56 Sverdrup (Sv) (1 Sv = $10^6m^3s^{-1}$), which is similar to those from previous studies (Takikawa et al. 1999; Teague et al. 2002). The volume transport time series of the Tsushima Warm Current from HYCOM correlates to a high degree with that from the ADCP observation (the correlation coefficient between the two is 0.82). The spatiotemporal structures of the currents as well as temperature and salinity from HYCOM are comparable to the observed ones.

• Earthquakes and Structures
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• v.11 no.3
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• pp.461-481
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• 2016

The research described in this paper investigates the seismic behaviour of lightly reinforced concrete (RC) bearing sandwich panels, heavily conditioned by shear deformation. A numerical model has been prepared, within an open source finite element (FE) platform, to simulate the experimental response of this emerging structural system, whose squat-type geometry affects performance and failure mode. Calibration of this equivalent mechanical model, consisting of a group of regularly spaced vertical elements in combination with a layer of nonlinear springs, which represent the cyclic behaviour of concrete and steel, has been conducted by means of a series of pseudo-static cyclic tests performed on single full-scale prototypes with or without openings. Both cantilevered and fixed-end shear walls have been analyzed. After validation, this numerical procedure, including cyclic-related mechanisms, such as buckling and subsequent slippage of reinforcing re-bars, as well as concrete crushing at the base of the wall, has been used to assess the capacity of two- and three-dimensional low- to mid-rise box-type buildings and, hence, to estimate their strength reduction factors, on the basis of conventional pushover analyses.

• Magazine of the Korean Society of Agricultural Engineers
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• v.40 no.2
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• pp.59-68
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• 1998

This study was conducted to derive optimal design floods by generalized gamma distribution model of the annual maximum series at eight watersheds along Geum, Yeongsan and Seomjin river systems. Design floods obtained by different methods for evaluation of parameters and for plotting positions in the generalized gamma distribution model were compared by the relative mean errors and graphical fit along with 95% confidence limits plotted on gamma probability paper. The results were analyzed and summarized as follows. 1. Basic statistics and parameters were calculated by the generalized gamma distribution model using different methods for parameters. 2. Design floods according to the return periods were obtained by different methods for evaluation of parameters and for plotting positions in the generalized gamma distribution model. 3. It was found that design floods derived by sundry averages method for parameters and Cunnane method for plotting position in the generalized gamma distribution are much closer to those of the observed data in comparison with those obtained by the other methods for parameters and for plotting positions from the viewpoint of relative mean errors. 4. Reliability of design floods derived by sundry averages method in the generalized gamma distribution was acknowledged within 95% confidence interval.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.4
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• pp.106-115
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• 2019

A sharing economy has emerged through today's trust-building mechanisms, and a sharing economy is called a future economic model through a positive future market prospect. In this context, while the overseas sharing economic business is becoming a global trend, the domestic sharing economic business is busy following the global trend. The purpose of this study is to investigate the development direction of sharing economic business in Korea. First, the sharing economic cases of 50 oversea and domestic businesses were analyzed by time series analysis. Next, a cross-country analysis to analyze the business distribution and KCERN's sharing economic model through sharing economic cube model was conducted. Finally, profit model analysis through business case study and the relationship between the derived factors were investigated. As a result of the analysis, this study found comparative trends between overseas and domestic including differences in cultural and institutional environments and profit models. This study suggested directions for domestic sharing economy business.

• Nuclear Engineering and Technology
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• v.31 no.6
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• pp.618-630
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• 1999

An analytical model that includes the steam condensation effect has been derived and a parametric study has been performed. In addition, a series of experiments were performed and a total of 34 experimental data for the onset of CCFL in nearly horizontal countercurrent two-phase How have been obtained for various flow rates of water. Comparisons of the present CCFL data with slug formation models show that the agreement between the present as well as the existing model and the data is about the same. However, the deviation between the Taitel and Dukler's model predictions and the data is the largest when if j$_{f}$<0.04 m/s. A parametric study of the effect of the steam condensation using the present model shows that, when all local conditions are similar, the model predicted local gas velocities that cause the onset of flooding are slightly lower when condensation occurred. Based on the visual observation and the evaluation of the present work, it has been concluded that the criterion derived for the onset of slug flow can be directly used to predict the onset of inner flooding in nearly horizontal two-phase flow within the experimental ranges of the present work.