• Journal of the Korean Institute of Gas
• /
• v.15 no.4
• /
• pp.56-61
• /
• 2011

For the prevention of air pollution, the CNG vehicles have been supplied since 2006. The spread of CNG vehicles has decreased the level of air pollution. Declared goals of Korean Ministry of Environment (ME) are to supply CNG city bus by 90% by 2012. CNG bus explosion has exacerbated commuters' safety concerns, it has caused the barrier to the installation of CNG station. In this study, the sensor was installed for the safety improvement of CNG station. When new sensors were installed, a problem was encountered by a line of communication. To solve the installation problem, we carried out the monitoring of data communication network by USN technology.

• Journal of Korean Society for Atmospheric Environment
• /
• v.8 no.2
• /
• pp.93-99
• /
• 1992

Recently a passive $NO_2$ samplers have been frequently used for the measurement of $NO_2$ concentration in the atmosphere because of its simplicity and high accuracy. But these samplers have a defect that the amount of $NO_2$ adsorbed is increased by wind. In this study, the inlet of sampler was covered with a draft shield made by 325 mesh stainless sieve to eliminate the effect. But it was expected that $NO_2$ diffusion was interrupted by the draft shield. In order to conform this phenomenon, samplers with and without draft shield were exposed to a box filled with 1-1.1ppm $NO_2$. The result indicated that draft shield nearly did not disturb $NO_2$ diffusion. To protect samplers from dust, sunshine, precipitation and vertical wind effects, these samplers were placed into a shelter during the field test. The data obtained in this study was compared with the data from the ambient air monitoring network. The coefficient of correlation(r) between the two data was 0.9995 for the test period of up to 35days. The results of this study indicate that the type of $NO_2$ samplers with draft shield in shelter used in this study can be used for measuring $NO_2$ concentrations in the ambient air relatively for a long period over 30 days.

• International Journal of Computer Science & Network Security
• /
• v.22 no.8
• /
• pp.371-379
• /
• 2022

The environment in Kosovo is a topic of concern for the citizens and the state because of the temperatures that affect the health of the citizens and the climate around the world. Kosovo's climate is related to its geographical position. Stretching in the middle latitude, Kosovo's climate depends on the amount of heat coming from the Sun, the proximity of the Adriatic Sea, the Vardar valley, the openness to the north. In order to better understand the climatic features of Kosovo, one must know the elements of the climate such as: sunshine, temperature, precipitation, atmospheric pressure, winds. The Meteorological Institute of Kosovo is responsible for measuring temperatures in Kosovo since 2014 and until now 12 meteorological stations have been operationalized with automatic measurement and real-time data transfer to the central system for data collection and archiving. The hydrometeorological institute lacks an application for measuring temperatures in all the countries of Kosovo. Software applications are generally built to suit the requirements of different governments and clients in order to enable easier management of the jobs they operate on. One of the forms of application development is the development of mobile applications based on android. The purpose of the work is to create a mobile application based on the Android operating system that aims to display information about the weather, this type of application is necessary and important for users who want to see the temperature in different places in Kosovo, but also the world. This type of application offers many options such as maximum temperature, minimum temperature, humidity, and air pressure. The built application will have real and accurate data; this will be done by comparing the results with other similar applications. Such an application is necessary for everyone, especially for those people whose daily work is dependent on the weather or even for those who decide to spend their vacations, such as summer or winter. In this paper, comparisons are also made within android applications for tablets, televisions and smart watches.

• Journal of Korean Society for Atmospheric Environment
• /
• v.28 no.6
• /
• pp.697-705
• /
• 2012

Particulate matter (PM) data collected from the Urban Air Monitoring Network in Busan during the period from 2006 through 2010 were statistically examined and analyzed to estimate the probability of exceeding $PM_{2.5}$ 24 hour and annual standard to be implemented from January $1^{st}$, 2015. For Jangrimdong, Yeonsandong, Kijangeup, and Jwadong where simultaneous measurement of $PM_{10}$ and $PM_{2.5}$ was conducted, the probability of exceeding $PM_{2.5}$ standards was estimated using $PM_{2.5}$ data measured on site. For other areas where there were no measured $PM_{2.5}$ data available, the probability of exceeding $PM_{2.5}$ standards was statistically estimated using $PM_{10}$ measured on site and $PM_{2.5}/PM_{10}$ ratios obtained from the four stations where both $PM_{2.5}$ and $PM_{10}$ were monitored simultaneously. At Jangrimdong, Yeonsandong, Kijangeup, and Jwadong, mean value of annual 99 percentile of 24 hr average $PM_{2.5}$ for 5 years from 2006 through 2010 was 99.3, 74.5. 57.0, and $62.5{\mu}g/m^3$, respectively, and the probability of exceeding $PM_{2.5}$ 24 hr standard was estimated at 100%. For areas where there were no measured $PM_{2.5}$ data available, the estimated probability of exceeding $PM_{2.5}$ 24 hr standard was more than 0.82. Mean value of annual average $PM_{2.5}$ from 2008 through 2010 was 31.7 and $27.6{\mu}g/m^3$ for Jangrimdong and Yeonsandong, respectively, which exceeded $PM_{2.5}$ annual standard of $25{\mu}g/m^3$. Mean value of annual average $PM_{2.5}$ during the same period for Kijangeup and Jwadong was 19.2 and $20.7{\mu}g/m^3$, respectively, which satisfied $PM_{2.5}$ annual standard. For other areas where there were no measured $PM_{2.5}$ data available, the probability of exceeding $PM_{2.5}$ annual standard was more than 0.95 except Taejongdae and Kwangahndong. With $PM_{10}$ and $PM_{2.5}$ data measured at 17 Urban Air Monitoring Stations in Busan, the probability of exceeding $PM_{2.5}$ standards was estimated to be very high for almost all areas. This result indicates that proper measures to mitigate $PM_{2.5}$ in Busan should be investigated and established as soon as possible.

• Journal of Biosystems Engineering
• /
• v.43 no.2
• /
• pp.148-159
• /
• 2018

Purpose: Unmanned air vehicle (UAV) remote sensing was applied to test various vegetation indices and make prediction models of protein content of rice for monitoring grain quality and proper management practice. Methods: Image acquisition was carried out by using NIR (Green, Red, NIR), RGB and RE (Blue, Green, Red-edge) camera mounted on UAV. Sampling was done synchronously at the geo-referenced points and GPS locations were recorded. Paddy samples were air-dried to 15% moisture content, and then dehulled and milled to 92% milling yield and measured the protein content by near-infrared spectroscopy. Results: Artificial neural network showed the better performance with $R^2$ (coefficient of determination) of 0.740, NSE (Nash-Sutcliffe model efficiency coefficient) of 0.733 and RMSE (root mean square error) of 0.187% considering all 54 samples than the models developed by PR (polynomial regression), SLR (simple linear regression), and PLSR (partial least square regression). PLSR calibration models showed almost similar result with PR as 0.663 ($R^2$) and 0.169% (RMSE) for cloud-free samples and 0.491 ($R^2$) and 0.217% (RMSE) for cloud-shadowed samples. However, the validation models performed poorly. This study revealed that there is a highly significant correlation between NDVI (normalized difference vegetation index) and protein content in rice. For the cloud-free samples, the SLR models showed $R^2=0.553$ and RMSE = 0.210%, and for cloud-shadowed samples showed 0.479 as $R^2$ and 0.225% as RMSE respectively. Conclusion: There is a significant correlation between spectral bands and grain protein content. Artificial neural networks have the strong advantages to fit the nonlinear problem when a sigmoid activation function is used in the hidden layer. Quantitatively, the neural network model obtained a higher precision result with a mean absolute relative error (MARE) of 2.18% and root mean square error (RMSE) of 0.187%.

• Journal of the Korean earth science society
• /
• v.44 no.1
• /
• pp.62-78
• /
• 2023

The purpose of this study is to analyze the field of Earth science at a science fair. For this purpose, 566 pieces of data spanning 21 years (2000 to 2020), acquired from entries in the Earth Science section on the science fair website, were analyzed using the semantic network method. As a result, geoscience topics have been actively explored in works submitted for the Earth Science section of the science fair. Fossils from the Cretaceous period of the Mesozoic Era were particularly predominant. Together with these, keywords corresponding to astronomy, space science, and atmospheric science formed a small-scale network. Astronomy and space science mainly dealt with the dynamic characteristics of asteroids, Venus, and Jupiter. Other subjects included the solar system, sunspots, and lunar phases. Atmospheric science has focused on atmospheric physics, atmospheric observation and analysis technology, atmospheric dynamics, air quality monitoring, while marine science has been limited to physical oceanography and geologic oceanography. This study, is expected to help select Earth Science topics and conduct inquiry activities in schools.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.18 no.5
• /
• pp.1122-1127
• /
• 2014

WLAN is affordability, flexibility, and ease of installation, use the smart device due to the dissemination and the AP (Access Point) to the simplification of the Office building, store, at school. Wi-Fi radio waves because it uses the medium of air transport to reach areas where security threats are always exposed to illegal AP installation, policy violations AP, packet monitoring, AP illegal access, external and service access, wireless network sharing, MAC address, such as a new security threat to steal. In this paper, signature-based of wireless intrusion detection system for Snort to suggest how to develop. The public can use hacking tools and conduct a mock hacking, Snort detects an attack of hacking tools to verify from experimental verification of the suitability of the thesis throughout.

• Journal of Korean Society for Atmospheric Environment
• /
• v.23 no.3
• /
• pp.322-331
• /
• 2007

In this study, we have analyzed $PM_{10}$ concentration measured at Incheon Regional Air Monitoring Network (10 stations) and meteorological data at Incheon Weather Station to investigate factors (i.e. wind direction, wind speed, relative humidity, major meteorological phenomenon, and sea-land breezes existence) influencing $PM_{10}$ concentration in Incheon during 2005. Statistical differences among meteorological factors were assessed by Kruskal-Wallis test or Mann-Whitney U test. The main conditions causing high $PM_{10}$ concentration are summarized below; 1. When westerly wind prevailed (however, $PM_{10}$ decreased when winds were blowing from the east or north). 2. When the winds were calm, owing to accumulation of nearby emissions under stagnant conditions, or when the wind speed is in excess of 6 m/s, which shows the effect of fugitive dust produced by wind erosion. 3. Under the condition of high relative humidity and poor diffusion based on meteorological phenomenon such as fog, mist, and haze. 4. When the Sea-Land breezes existed, which occurred 70 days in Incheon during 2005 and contributed significantly to high $PM_{10}$ concentration in the coastal urban area. In conclusion, we have found that the meteorological factors have influence on $PM_{10}$ concentration in Incheon.

• Korean Journal of Environmental Agriculture
• /
• v.19 no.4
• /
• pp.345-350
• /
• 2000

The objectives of this study were to find out distribution of heavy metal contents in the soils of Hanam city and to provide base-line data towards development of an eco-city Hanam. One hundred surface soil (0-20 cm) samples were collected from rice paddy field, cultivated upland, forest, riverside and other areas. The samples were air-dried, sieved to pass through 2 mm sieves, followed by analyses for As, Cd, Cu, Pb and Zn by the standard method set by the ministry of environment. All the average heavy metal contents were close to background level and were much lower than concern level of the Soil Environment Conservation Act of Korea. However, some individual heavy metal contents were higher than the action level. Since natural environment including soil environment of Hanam city is being destroyed rapidly and the number of the sampling points allocated to Hanam city based on the soil contamination monitoring network of the ministry of environment is only 6, an in-depth soil survey for contamination of Hanam city is highly recommended.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.10 no.5
• /
• pp.364-371
• /
• 2017

TPMS is a vehicle electric system that measures the air pressure of a tire, and informs the driver of current tire states. The TPMS sensor typically uses unidirectional communication for small size, light weight, and low power. The transmission period of the sensor indicates the service quality of monitoring the tire. In order to determine the optimal transmission period, frame collision probability and the life time of the sensor should be analyzed. In this paper, collision probability model using Venn diagram is designed in low power TPMS with the normal and warning mode. And the life time and a collision probability were analyzed with the ratio(n) of the normal mode to warning mode transmission period. As a result, $T_{nP}=31sec$ and $T_{wP}=2.4sec$ at 5 years, and $T_{nP}=71sec$ and $T_{wP}=2.5sec$ at 7 years.