• Journal of the Korean Data and Information Science Society
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• v.20 no.2
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• pp.293-299
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• 2009

In this article, we consider linear models such as regression, ARIMA (autoregressive integrated moving average), and regression+ARIMA (regression with ARIMA errors) for predicting hourly ozone concentration level in two areas of Daegu. Based on RASE(root average squared error), it is shown that the ARIMA is the best model in one area and that the regression+ARIMA model is the best in the other area. We further analyze the residuals from the optimal models, so that we might predict the ozone warning days where at least one of the hourly ozone concentration levels is over 120 ppb. Based on the training data in the years from 2000 to 2003, it is found that 35 ppb is a good cutoff value of residulas for predicting the ozone warning days. In on area of Daegu, our method predicts correctly one of two ozone warning days of 2004 as well as all of the remaining 364 non-warning days. In the other area, our methods predicts correctly all of one ozone warning days and 365 non-warning days of 2004.

• Human Ecology Research
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• v.55 no.6
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• pp.661-673
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• 2017

This study analyzes the current wearing status and awareness of warning clothing for elementary school students as well as to identify points of improvement for traffic accident prevention and clothing safety education. A survey was conducted on 279 elementary $5^{th}$ and $6^{th}$ graders in the Incheon area and Ansan in 2017 June & July. The results showed that more than 2/3 of participants had no experience wearing warning clothing. Second, 63% of participants answered 'traffic accident prevention' as the main purpose of warning clothing, showing that about 2/3 are aware of the importance. Third, yellow was the most preferred color of fluorescent material for warning clothing with a significant difference of preference by grade. The favorite color combination of participants was yellow & orange followed by yellow & light green, but showed a significant difference between boys and girls. Fourth, the most preferred form of warning clothing was fluorescent short sleeves and shorts without reflective tape, suggesting that students paid more to the purpose for reflective tape. Fifth, while 68% of participants were negative towards wearing safety clothes that are currently available, 66% were willing to try safety clothes if the color and the design improved. The results suggest an improved education with more emphasis on the purpose of clothing safety. Color and design adjustment of the current warning clothing is also recommended for a more active participation by elementary school students.

• Journal of Korean Society of Transportation
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• v.27 no.5
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• pp.63-74
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• 2009

One of the effective countermeasures for preventing traffic accidents is to provide traffic safety warning information to drivers. Provision of warning information would lead to safer driving to avoid accident occurrence. This study investigated the effects of in-vehicle warning information on driver's behavior. A variety of warning information contents using text, sound, and pictograms were prepared for the field experiments. Individual vehicle speed and acceleration data, which represent quantitative drivers' behavior in response to in-vehicle warning information, were collected using differential global positioning systems (DGPS). Statistical analyses including ANOVA and Tukey's pairwise comparison were conducted. It is expected that the results could be invaluable for designing more effective warning information.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.11
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• pp.2069-2076
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• 2008

In this paper, we develop an electrostatic monitoring system which is composed of an electrostatic prediction system and a warning message transmission system. The electrostatic prediction system in a factory receives the value of electrostatic charge from the electrostatic sensor and predicts the next value by using past data and sends the value to the warning message transmission system through the bluetooth communication. The warning message transmission system gets a warning signal and transmits the warning message to the worker's cellphone through a commercial SMS web by a socket program running on Windows PC in a control room. We propose electrostatic forecasting algorithms based on LSR(least square regression) using weight factors in an electrostatic prediction system. Simulation results show that the algorithm with dynamically variable weight factors is best with 64.69V standard deviation and a warning message transmitted by the warning message transmission system is displayed on cellphone after about 5 seconds.

• Journal of Korean Society for Quality Management
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• v.12 no.2
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• pp.15-24
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• 1984

Since W.A. Shewhart (1931) developed the quality control method using the control chart, many theoretical and empirical works about such an analytical method have been done. However there are two major methods relating to the control chart analysis; the conventional 3 sigma control method and the warning limit method which has been suggested as a modification of the former. The conventional 3 sigma method requires to take a remedial action only when a quality characteristic is beyond the control limit (3 sigma). However, once a quality characteristic is over the control limit, searching and repairing an assignable cause requires time consuming job and high costs. Therefore if we set the warning limit between the central line and the control limit, we will be able to take remedial measures before too late. In spite of its advantage, much attention has not been paid to use the control chart with warning limit in Korean industries. The main object of this study is to examine improvement of quality and productivity when the control chart with warning limit is used.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.189-192
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• 2005

Desertification is one of the main global environmental phenomena. It has resulted in deterioration environment and poor economy, and imposed threat to the surviving environment of the overall mankind. Therefore, creating of methods for monitoring and estimate of risk desertification are necessary. Early warning system is one of important ways for monitoring and forecasting of desertification. Remote Sensing and GIS technology are as suitable tools and methods for early warning system. In this aim, we have evaluated of applications of remote sensing and GIS in monitoring and estimating desertification process (case study in Fars Province of Iran). In this research, we have considered erosion and vegetation cover parameters as main factors affecting in desertification process. The result shows that remote sensing and GIS technology could be useful in evaluation of desertification as one method for desertification early warning. Also, Results suggested that erosion and plant cover are affecting in develop the desertification process in study area.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.10a
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• pp.540-543
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• 2011

The vehicle's warning sounds are one of the important parts of overall vehicle quality, so the study of these sounds is increasing. In this study, the experiment of reproducing performance related to speaker position was studied. Based on the result of jury test, sound analysis method was developed to reflect the perception of warning sound according to vehicle speed and the development process of warning sounds was suggested.

• Structural Engineering and Mechanics
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• v.16 no.4
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• pp.441-468
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• 2003

This paper investigates the structural behavior of modular falsework system under sequential pattern loads. Based on the studies of 25 construction sites, the pattern load sequence modeling is defined as models R (rectangle), L and U. The study focuses on the system critical loads, regions of largest reaction forces, discrepancy between the pattern load and the uniform load, and the warning-system plan. The analysis results show that the critical loads of modular falsework systems with sequential pattern loads are very close to those with the uniform load used in design. The regions of largest reaction forces are smaller than those calculated by the uniform load. However, the regions of largest reaction forces of three models under sequential pattern loads can be considered as the crucial positions of warning-system based on the measured index of loading. The positions of the sensors for the warning-system for these three different models are not identical.

• Wind and Structures
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• v.15 no.4
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• pp.345-354
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• 2012

This work discusses the wind stability requirements specified by UN Reg. 27 on emergency car warning triangles, which are of mandatory use in many countries. Wind tunnel experiments have been carried out in order to determine aerodynamic coefficients of commercial warning triangles and the friction coefficients between the triangle legs and an asphalt base that fulfils the roughness requirements stated by Reg. 27 for wind stability certification. The wind stability specifications for warning triangles are reviewed, compared with pressure field measurements and discussed. Results of wind tunnel tests and comparison with field measurements reported in the literature show that the requirements could be excessively conservative.

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.261-263
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• 2004

This paper studies the lighting pattern control of a high-brightness LED warning light. The driving circuit for the warning light is composed of a full-wave rectified circuit and of a control circuit using a micro-controller (AT89c2051). The micro-controller is programmed in a suitable manner to accomodate a number of variable lighting patterns and to adjust the blinking speed. To reduce the total number of LEDs installed a special consideration is made to the bundled pattern in a lamp module which is lit simultaneously. The resultant LED warning light has merits not only over the conventional incandescent warning light on the energy saving aspect but also over some other LED-type ones in the market.