• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.3
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• pp.307-316
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• 2016

A multiple radar system is comprised of early warning radar for fast detection of a target and air defense radar for precision intercept. For this reason, target take-over process is required between the two radars. The target take-over should be performed at an appropriate time by consideration of stable tracking and effective fire control. In this paper, operation characteristics of multiple radar system are analyzed and target take-over time determination method using estimation of target tracking performance is proposed for high-velocity targets. The proposed method is validated with ballistic target defense scenarios in the developed integrated simulator.

• Journal of KIBIM
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• v.6 no.2
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• pp.39-46
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• 2016

While institutional matters such as improvement on Basic Guidelines for Construction Safety are greatly concerned to reduce falling accidents at construction sites, there are short of studies on how to practically predict accident signs at construction sites and to preemptively prevent them. As one of existing accident prevention methods, it was attempted to build the early warning system based on standardized accident scenarios to control the situations. However, the investment cost was too high depending on the site situation, and it did not help construction workers directly since it was developed to mainly provide support operational work support to safety managers. In the long run, it would be possible to develop the augmented reality based accident prevention method from the worker perspective by extracting product information from BIM, visually rendering it along with site installation materials term and comparing it with the site situation. However, to make this method effective, the BIM model should be implemented first and the technology that can promptly process site situations should be introduced. Accordingly, it is necessary to identify risk signs through lightweight image processing to promptly respond only with currently available resources. In this study, it was intended to propose the system concept that identified potential risk factors of falling accidents by histogram equalization, which was known as the fastest image processing method presently, used visual words, which could enhance model classification by wording image records, to determine the risk factors and notified them to the work manager.

• Journal of Korean Society of societal Security
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• v.2 no.2
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• pp.49-54
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• 2009

High incident of accidents in construction jobsite became a social problem. According to the International Labour Organization (ILO), more than 60,000 fatal accidents occur each year in construction workplace worldwide. This number of accidents accounts for about 17 percent of all fatal workplace accidents. Especially, accidents from struck-by and falls comprise of over 60 percent of construction fatalities. This paper introduces a prototype of a received signal strength index (RSSI)-based safety monitoring to mitigate the potential accidents caused by falls and struck-by. Correlation between signal strength and noise index is examined to create the distance profile between a transmitter and a receiver. Throughout the distributed sensor nodes attached on potential hazardous objects, the proposed prototype envisions that construction workers with a tracker-tag can identify and monitor their current working environment in construction workplace, and early warning system can reduce the incidents of fatal accident in construction job site.

• Journal of Technology Innovation
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• v.16 no.1
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• pp.107-139
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• 2008

We studied how to achieve successful implementation of massive research and development projects requiring collaboration among industries, universities and government-supported research institute. We have set up an engineering process innovation model to be deemed most adequately for all practical purposes, relying on the theoretical studies on the merits and analysis of the effect of the information system based on Milestone Management, Work Breakdown Structures and Web, which is known to be effective for research project (schedule) management and the objective management, and implemented a real-world web-based project objective management system. After a review of various R & D Project Schedule Management methods, we found that this information system was very compatible with project objective management. This project objective management information system carries out research and development projects effectively and efficiently, getting together in cyber-space and sharing information, and has been equipped with an Early Warning Subsystem to allow for pre-analysis and timely response to potential problems arising from the course of the project. The system also contains an Executive Information System that in real time, automatically provides the management information required by managers with the rate of project progress (achievement, fulfillment and delay). Lastly, actual progress can be cross-checked through both on-line objective management on the web-based information system and design review meeting held on site, to improve the efficiency and validity of the information system. Moreover, overall effect was analyzed through questionnaires on how well the system and generated information meet requirements and on the ultimate impact of the system upon objective management and communication. The questionnaire on the system effect revealed that the information system was useful to objective management and communication, and that the quality of the system was more than acceptable as well.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.611-614
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• 2009

Understanding the severity of the typhoon-induced storm-surge helps in planning reaction and in preventing further disaster. Natural disasters due to the storm-surge are predictable from accurate observations and forecasts from numerical simulations. What we can do is to make intelligent effort to minimize the loss due to the disaster to the most extent with the technology of early warning, forecast and prevention activity. In this paper, we propose the design of GIS-based Web Service System to visualize the time-varying storm-surge's height and wind field data effectively with 3 different kinds of resolution for predict and prevent storm-surge disasters. This system is one of the efforts to provide the storm-surge forecast service to general public and share two-way more helpful information to coastal resident through the Internet.

• The Plant Pathology Journal
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• v.25 no.3
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• pp.213-219
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• 2009

An understanding of anthracnose (Colletotrichum acutatum) infections, including the infection of flowers and latent infection early in the season, is necessary to achieve successful control by means of properly timed spraying with a curative fungicide. In the present study, latent anthracnose infection of chili was investigated under greenhouse and field conditions in 2007-2008. Flowers on greenhouse-grown seedlings were infected and 11% of the young fruits subsequently showed symptoms of anthracnose. Apparently healthy-looking green peppers obtained from unsprayed fields or an organic market also exhibited symptoms of anthracnose after 4 days of incubation under high moisture conditions at $25^{\circ}C$; less than 1% of the peppers were found to be latently infected. To determine the natural timing of infection in the field, 3,200 fruits were wrapped in paper bags and then selectively unwrapped and examined for signs of infection. Field experiments were conducted at Suwon (cvs. Yokkang, Manitta, Olympic) and Asan (cv. Chunhasangsa) in 2008. The 7- to 10-day wrapping periods were July 25-31, July 31-August 7, August 7-15, August 15-24, and August 24-September 3. The 1-to 2-month wrapping periods were from July 4, July 31, and August 15 until harvest (Sept. 3). The controls consisted of 1,712 field-grown non-wrapped fruits. The rates of infection on the various cultivars were Yokkang 55%, Manitta 37%, Olympic 55%, and Chunhasangsa 20%. A distinct period in which anthracnose infection suddenly increased could not be identified; however, attempts to guess the approximate timing of field infection showed that 0-39% of the plants had latent infections, while depending on the cultivar, 8-14% of the plants examined in August and 4-13.5% of the those examined during May-July showed symptoms of infection. Delaying fungicide spraying by 24 and 48 h after artificial infection decreased the rates of infection by 10% and 25-30%, respectively. Chemical control of anthracnose based on a forecasting model should be considered starting from the transplanting stage, with spraying within a day after warning and care being taken not to latently infect apparently healthy pepper fruits.

• Journal of Korean Neurosurgical Society
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• v.56 no.6
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• pp.455-462
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• 2014

Objective : To propose a new measure for effective monitoring of intraoperative somatosensory evoked potentials (SEP) and to validate the feasibility of this measure for evoked potentials (EP) and single trials with a retrospective data analysis study. Methods : The proposed new measure (hereafter, a slope-measure) was defined as the relative slope of the amplitude and latency at each EP peak compared to the baseline value, which is sensitive to the change in the amplitude and latency simultaneously. We used the slope-measure for EP and single trials and compared the significant change detection time with that of the conventional peak-to-peak method. When applied to single trials, each single trial signal was processed with optimal filters before using the slope-measure. In this retrospective data analysis, 7 patients who underwent cerebral aneurysm clipping surgery for unruptured aneurysm middle cerebral artery (MCA) bifurcation were included. Results : We found that this simple slope-measure has a detection time that is as early or earlier than that of the conventional method; furthermore, using the slope-measure in optimally filtered single trials provides warning signs earlier than that of the conventional method during MCA clipping surgery. Conclusion : Our results have confirmed the feasibility of the slope-measure for intraoperative SEP monitoring. This is a novel study that provides a useful measure for either EP or single trials in intraoperative SEP monitoring.

• Environmental Engineering Research
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• v.11 no.5
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• pp.277-284
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• 2006

The genetic toxicity of environmental pollutants, namely, nonylphenol (NP), bisphenol A (BPA) and chloropyriphos (CP) was investigated in aquatic sentinel species, freshwater crustacean, Daphnia magna, and larva of aquatic midge, Chironomus tentans, using Comet assay. Physiological effect of such pollutants was also investigated by studying the specimens' rates of reproduction, growth and survival. Acute toxicity results showed that, as expected, Daphnia was more sensitive than Chironomus to chemical exposure. The order of acute toxicity was CP > NP > BPA in D. magna and NP > CP > BPA in C. tentans. BPA may exert a genotoxic effect on D. magna and C. tentans, given that DNA strand breaks increased in both species exposed to this compound, whereas NP- and CP-induced DNA damage occurred only in C. tentans. In vivo genotoxic data obtained in aquatic sentinel species could provide valuable information for freshwater quality monitoring. The experiments with NP-exposed D. magna showed that the pollutant has long-term effects on reproduction, whereas no short-term effect on DNA integrity was found, being an example of a false-negative result from the biomarkers perspective. This result could be interpreted that other mechanism than genetic alteration might be involved in NP-induced reproduction failure in D. magna. False-positive results from the genotoxic biomarker obtained in BPA-exposed D. magna and in NP-exposed C. tentans make it difficult to use DNA integrity as an early warning biomarker. However, as the mere presence of genotoxic compounds, which are potentially carcinogenic, is of high concern to human and ecosystem health, it could also be important to rapidly and effectively detect genotoxic compounds in the aquatic system in ways that do not necessarily accompany a higher level of alteration. Considering the potential of D. magna and C. tentans as bioindicator species, and the importance of genotoxic biomarkers in ecotoxicity monitoring, DNA damage in these species could provide useful information for environmental risk assessment.

• The Korean Journal of Quaternary Research
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• v.19 no.2
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• pp.74-79
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• 2005

Recently, several attempts have been made to provide reasonable information on unusual severe weather phenomena such as tolerant heavy rains and very wild typhoons. Quantitative precipitation forecasts and probabilistic quantitative precipitation forecasts (QPFs and PQPFs, respectively) might be one of the most promising methodologies for early warning on the flesh floods because those diagnostic precipitation models require less computational resources than fine-mesh full-dynamics non-hydrostatic mesoscale model. The diagnostic rainfall model used in this study is the named QPM(Quantitative Precipitation Model), which calculates the rainfall by considering the effect of small-scale topography which is not treated in the mesoscale model. We examine the capability of probabilistic diagnostic rainfall model in terms of how well represented the observed several rainfall events and what is the most optimistic resolution of the mesoscale model in which diagnostic rainfall model is nested. Also, we examine the integration time to provide reasonable fine-mesh rainfall information. When we apply this QPM directly to 27 km mesh meso-scale model (called as M27-Q3), it takes about 15 min. while it takes about 87 min. to get the same resolution precipitation information with full dynamic downscaling method (called M27-9-3). The quality of precipitation forecast by M27-Q3 is quite comparable with the results of M27-9-3 with reasonable threshold value for precipitation. Based on a series of examination we may conclude that the proosed QPM has a capability to provide fine-mesh rainfall information in terms of time and accuracy compared to full dynamical fine-mesh meso-scale model.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.9
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• pp.841-849
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• 2008

Natural disaster such as inundation due to the typhoon induced storm-surge has inflicted severe losses on the coastal area. The problem of global warming and sea surface rising has issued and thus influences the increase of frequency and potential power of storm-surge. What we can do is to make intelligent effort to predict and prevent the losses through the early warning and prevention activity from the accurate prediction and forecasting about the time-varying storm-surge height and its arriving time resulted from the numerical simulation with sea observations. In this paper, we developed the web service based GIS-Enabled storm-surge visualization system to predict and prevent the storm-surge disasters. Moreover. for more accurate topography around coastal area and fine-grid storm-surge numerical model, we have accomplished GIS-based coastal mapping through LiDAR measurement.