• Journal of Korea Water Resources Association
• /
• v.37 no.11
• /
• pp.969-978
• /
• 2004

According to the report of hydrologic modeling study, from a quantitative point of view, a lumped model is more efficient than a distributed model. A distributed model has to simplify geospatial characteristics for the shake of restricted application on computer calculation and field observation. In this reason, a distributed model can not help having some errors of water quantity modelling. However, considering a distribution of rainfall-runoff reflected spatial characteristics, a distributed model is more efficient to simulate a flow of surface water, The purpose of this study is modeling of spatial rainfall-runoff of surface water using grid based distributed model, which is consisted of storage function model and essential basin-channel parameters( slope, flow direction & accumulation), and that procedure is able to be executed at a personal computer. The prototype of this model is developed in Heongseong Multipunose Dam basin and adapted in Hapchon Multipurpose Dam basin, which is larger than the former about five times. The efficiency coefficients in result of two dam basin simulations are more than about 0.9, but ones at the upstream water level gauge station meet with bad result owing to overestimated rating curves in high water level. As a result of this study, it is easily implemented that spatially distributed rainfall-runoff model using GIS, and geophysical characteristics of the catchment, hereafter it is anticipated that this model is easily able to apply rainfall data by real time.

• Journal of Korea Water Resources Association
• /
• v.38 no.3 s.152
• /
• pp.213-222
• /
• 2005

This study is a sensitivity analysis of the parameters which affect the simulation results under various design rainfall conditions, using the SWMM model, for three selected basins in urban areas. The sensitivity of the peak flow rate is defined by $S_Q$ (=1.0 - (min. ratio of peak flow rate/max. ratio of peak flow rate)), and the rainfall conditions are classified in terms of design rainfall frequency, duration, and distribution. The simulation results show that in most conditions the parameters - the impermeable area ratio, the sewer slope, and the initial infiltration capacity - have more significant effects on the results than other parameters. As the design rainfall frequency increases, the sensitivity of the sewer slope and sewer roughness increases, while the parameters related with the surface runoff decrease. When the rainfall duration increases, the sensitivities of most parameters of surface runoff and sewer flow decrease. Also, at the 1st quarterly Huff rainfall distribution condition, the impermeable area ratio has high sensitivity, but at the 4th quarterly condition the parameters related with sewer flow show higher sensitivities. These tendencies can be explained by considering the procedure for computing the effective rainfall and kinematic wave on the surface and sewer flow.

• Food Science of Animal Resources
• /
• v.29 no.6
• /
• pp.695-701
• /
• 2009

This study was performed to evaluate the effectiveness of biological critical control points using the genetic profile of Escherichia coli isolates from pork cutting plants. Samples were collected from carcasses, equipment (knife, table, glove, transport belt, boning and skinning machine), the environment (wall and floor), and meat cuts during the cutting process from two plants. Pulsed-field gel electrophoresis (PFGE) was used to characterize the E. coli isolates. An identical genotype was detected from the carcasses, equipment, environment, and final meat cuts, and showed that the incoming carcasses, which were contaminated during transportation from slaughterhouses, were a major source of E. coli that was spread throughout processing. Also, consistent cross-contamination due to improper cleaning and disinfection procedures was another possibility. As a result, incoming carcasses and cleaning procedures should be considered critical control points in pork cutting plants, since a heating step is not used to inactivate microorganisms. Furthermore, the high rate (59.6%) of E. coli isolation indicates E. coli can be a good indicator in livestock processing plants even though it has genetic diversity.

• Korean Journal of Remote Sensing
• /
• v.37 no.6_2
• /
• pp.1837-1847
• /
• 2021

This study investigated wind corridors for the entire Suwon-city area using a geographic information system and a computational fluid dynamics model. We conducted numerical simulations for 16 inflow wind directions using the average wind speeds measured at the Suwon automated synoptic observation system (ASOS) for recent ten years. We analyzed the westerly (dominant wind direction) and easterly cases (not dominant but strong wind speed) in detail and investigated the characteristics of a wind speed distribution averaged using the frequencies of 16 wind directions as weighting factors. The characteristics of the wind corridors in Suwon city can be summarized as; (1) In the northern part of Suwon, complicated flows were formed by the high mountainous terrain, and strong (weak) winds and updrafts (downdrafts) were simulated on the windward (leeward) mountain slope. (2) On the leeward mountain slope, a wind corridor was formed along a valley, and relatively strong airflow flowed into the residential area. (3) The strong winds were simulated in a wide and flat area in the west and south part of Suwon city. (4) Due to the friction and flow blocking by buildings, wind speeds decreased, and airflows became complicated in the downtown area. (5) Wind corridors in residential areas were formed along wide roads and areas with few obstacles, such as rivers, lakes, and reservoirs.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.11
• /
• pp.157-165
• /
• 2018

Companies conduct R&D for continuous development and enhancement of corporate value, and obtain patents as an intangible asset resulting from this process. This study screened 103 medical device firms whose R&D information, patent information, and management performance information were all published to determine how R&D activities and patents affect corporate operational performance. The number of patents, R&D costs, company type and Inno-Biz of the company were set as independent variables, and the companies' sales, intangible assets, operating profit ratios, net profit margins, corporate ratings and profit-related financial ratios were used as dependent variables. The results confirmed that R&D expenditure had negative (-) effects on most indicators, including sales volume, operating profit ratio, and net profit ratio, while it had positive (+) [ED highlight - these are unnecessary if negative and positive are also written out.] effects only on intangible assets. Additionally, domestic patents were found to have negative (-) effects on sales, cash flow ratings, and dropped capital return, and positive (+) effects on net profit growth. Moreover, the business performance variables affected by the company characteristics were sales volume and cash flow ratings. The medical device industry is dominated by small and medium-sized businesses Although research and development activities and patents have been shown to have a negative impact on corporate management in the short term, they are expected to have a positive long-term impact when reflecting the characteristics of the medical device industry that must undergo clinical trials and authorization procedures after R&D.

• 동북아역사논총
• /
• no.60
• /
• pp.196-227
• /
• 2018

The issues of this study are as follows. First, I will examine the overall situation and transition trends of Tibetan research in Taiwan since the modern period, and examine the development and trends of Tibetan history research in Taiwan. Secondly, in order to satisfy the above, we will analyze trends of Taiwan's major Tibetan research institutes and scholars, and trace their trends and their trajectories. Third, the trend of Tibetan research in Taiwan may be a useful indicator for us to analyze research methods and trends of Taiwanese scholars. If there is a flow of features and transitions, the text will explore the reason. Fourth, one of the implications of this study is that it can trigger an understanding of locality in the structure of the central region, the Han Chinese minority, and the possession and distribution of academic reasoning. In other words, it should be noted that even though the same Tibetan research is conducted, China is in the position of the vested right to distribute 226 | 동북아역사논총 60호the central or ownership, while Taiwan has historical and territorial characteristics that deviate from such a gaze and attitude. Taiwan may be sensitive to the vertical concept understood as a change in the relationship between the state and the center, or whether it is applicable to Tibetan research. If there is such an academic climate, I would like to consider suggestions for us. This may provide a direction to view the academic issues of a few scholars, or even the domestic academic world as an independent object of more specific academic research.

• Journal of the Korea Society of Computer and Information
• /
• v.26 no.4
• /
• pp.11-19
• /
• 2021

An abnormal object refers to a person, an object, or a mechanical device that performs abnormal and unusual behavior and needs observation or supervision. In order to detect this through artificial intelligence algorithm without continuous human intervention, a method of observing the specificity of temporal features using optical flow technique is widely used. In this study, an abnormal situation is identified by learning an algorithm that translates an input image frame to an optical flow image using a Generative Adversarial Network (GAN). In particular, we propose a technique that improves the pre-processing process to exclude unnecessary outliers and the post-processing process to increase the accuracy of identification in the test dataset after learning to improve the performance of the model's abnormal behavior identification. UCSD Pedestrian and UMN Unusual Crowd Activity were used as training datasets to detect abnormal behavior. For the proposed method, the frame-level AUC 0.9450 and EER 0.1317 were shown in the UCSD Ped2 dataset, which shows performance improvement compared to the models in the previous studies.

• Journal of Korean Society of Disaster and Security
• /
• v.16 no.4
• /
• pp.157-164
• /
• 2023

The estuary dam is a structure installed and operated in a closed state except when flood event occurs to prevent inland saltwater intrusion and secure freshwater supply. However, the closed state of dam leads to issues such as eutrophication, so it is necessary to examine the extent of saltwater intrusion resulting from the opening of sluice gates. Groundwater, due to its subsurface conditions and slow flow characteristics, is widely analyzed using numerical models. OpenGeoSys, an open-source software capable of simulating Thermal- Hydraulic- Mechanical- Chemical phenomena, was adopted for this study. Simulations were conducted assuming natural flow conditions without dam and operating considering busy farming season, mostly from March to September. Verification of the model through analytical solutions showed error of 3.7%, confirming that OpenGeoSys is capable of simulating saltwater intrusion for these cases. From results simulated for 10 years, considering for the busy farming season, resulted in about 46% reduction in saltwater intrusion length compared to natural flow conditions, approximately 74.36 m. It may be helpful to make choices to use groundwater as a water resource.

• Journal of the Korea Convergence Society
• /
• v.5 no.4
• /
• pp.27-32
• /
• 2014

The information security policy is one of the most important tools for organization to manage the implementation and ensure the organizational security. However, we do not have metrics for measuring its effectiveness. The ultimate purpose of this study is to develop the measures of information security policy effectiveness. To do this, this study review data quality and information quality literatures and investigate appropriate subfactors for information security policy. Rooted in these concepts, we suggest accuracy, completeness, interpretability, and relevance from content aspect and understandability, concise representation, and amount from form aspect as factors for information security policy effectiveness.

• Tunnel and Underground Space
• /
• v.9 no.2
• /
• pp.149-157
• /
• 1999

A powerful numerical method that can be used for that purpose is the Discontinuous Deformation Analysis (DDA) method developed by Shi in 1988. In this method, rock masses are treated as systems of finite and deformable blocks. Large rock mass deformations and block movements are allowed. Although various extensions of the DDA method have been proposed in the literature, the method is not capable of modeling water-block interaction that is needed when modeling surface or underground excavation in fractured rock. This paper presents a new extension to the DDA method. The extension consists of hydro-mechanical coupling between rock blocks and water flow in fractures. A example of application of the DDA method with the new extension is presented. The results of the present study indicate that fracture flow could have a destabilizing effect on the tunnel stability.