• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5D
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• pp.635-644
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• 2009

Image processing technique in the outdoor environment is very sensitive, and it tends to lose a lot of accuracy when it rapidly changes by outdoor environment. Therefore, in order to calculate accurate traffic information using the traffic monitoring system, we must resolve removing shadow in transition time, Distortion by the vehicle headlights at night, noise of rain, snow, and fog, and occlusion. In the research, we developed a system to calibrate the amount of traffic, speed, and time occupancy by using image processing technique in a variety of outdoor environments change. This system were tested under outdoor environments at the Gonjiam test site, which is managed by Korea Institute of Construction Technology (www.kict.re.kr) for testing performance. We evaluated the performance of traffic information, volume counts, speed, and occupancy time, with 4 lanes (2 lanes are upstream and the rests are downstream) from the 16th to 18th December, 2008. The evaluation method performed as based on the standard data is a radar detection compared to calculated data using image processing technique. The System evaluation results showed that the amount of traffic, speed, and time occupancy in period (day, night, sunrise, sunset) are approximately 92-97% accuracy when these data compared to the standard data.

• Journal of Environmental Health Sciences
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• v.50 no.4
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• pp.282-290
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• 2024

Background: In order to evaluate the national effort to improve air quality through the Act on Air Quality Management Regions, an investigation of the current status of air quality in respective regions and the health impact of air pollution should be undertaken. Objectives: This study is a preliminary study on the status of PM_2.5 in the central region of South Korea and its health effects. It can be applied to the evaluation of the effectiveness of the Act on Air Quality Management Regions. Methods: Time series variation of PM_2.5 concentrations in the air quality management region (hereafter referred to as AQMR) and in the non-AQMR area in the central region of South Korea were created. Odds ratios (OR) were calculated based on the survey results of whether the residents of Jeollabuk-do were feeling anxiety caused by air pollution by sex, region, and regional characteristics. Relative risk (RR) values of lung cancer deaths in each city in the AQMR for the central region of South Korea were calculated. Results: During the period from Dec. 2018 to Dec. 2021, the average concentration of PM_2.5 was higher in the AQMR at 26.0 ㎍/m³ compared to 19.5 ㎍/m³ in the non-AQMR. The odds ratio (OR) calculated using data from the Jeonbuk Research Institute (2020) suggested that women were more uncomfortable or anxious about their lives due to air pollutants than were men. The OR evaluation results also showed that in terms of PM_2.5 sensitivity, residents in the non-AQMR were relatively more sensitive than those in the AQMR. The relative risk (RR) was calculated to evaluate the relationship between health hazards (PM_2.5) and diseases (lung cancer). As a result, for super-aged people over 80 years old, compared to the non-AQMR (Muju-gun and Jangsu-gun), the residents in the AQMR (Jeonju, Gunsan, and Iksan) have about twice the relative risk of lung cancer. Conclusions: It is necessary to make efforts to improve residents' health and extend their healthy lives through efforts to reduce air pollutants such as PM_2.5 in areas specially selected as an AQMR.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.3
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• pp.374-383
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• 2010

Microwave radar can penetrate cloud cover regardless of weather conditions and can be used day and night. Especially a ground-based polarimetric scatterometer has advantages of monitoring crop conditions continuously with full polarization and different frequencies. Kim et al. (2009) have measured backscattering coefficients of paddy rice using L-, C-, X-band scatterometer system with full polarization and various angles during the rice growth period and have revealed the necessity of near-continuous automatic measurement to eliminate the difficulties, inaccuracy and sparseness of data acquisitions arising from manual operation of the system. In this study, we constructed an X-band automatic scatterometer system, analyzed scattering characteristics of paddy rice from X-band scatterometer data and estimated rice growth parameter using backscattering coefficients in X-band. The system was installed inside a shelter in an experimental paddy field at the National Academy of Agricultural Science (NAAS) before rice transplanting. The scatterometer system consists of X-band antennas, HP8720D vector network analyzer, RF cables and personal computer that controls frequency, polarization and data storage. This system using automatically measures fully-polarimetric backscattering coefficients of rice crop every 10 minutes. The backscattering coefficients were calculated from the measured data at a fixed incidence angle of $45^{\circ}$ and with full polarization (HH, VV, HV, VH) by applying the radar equation and compared with rice growth data such as plant height, stem number, fresh dry weight and Leaf Area Index (LAI) that were collected at the same time of each rice growth parameter. We examined the temporal behaviour of the backscattering coefficients of the rice crop at X-band during rice growth period. The HH-, VV-polarization backscattering coefficients steadily increased toward panicle initiation stage, thereafter decreased and again increased in early-September. We analyzed the relationships between backscattering coefficients in X-band and plant parameters and predicted the rice growth parameters using backscattering coefficients. It was confirmed that X-band is sensitive to grain maturity at near harvesting season.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.3
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• pp.435-443
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• 2012

This study investigated soil carbon storage and microbial activities influenced by different management practices in rice paddies and pastures. Soils under a single-crop farming of rice (CON) and rice-Italian ryegrass rotation farming (IRG) were compared in Jangheung, Jeollanam-do, Seocheon and Cheonan, Chungcheongnam-do. Soils from pastures were analyzed to investigate the effect of duration period (P1, P2, P3) in Namwon, Jeollabuk-do and Seosan, Chungcheongnam-do. In rice paddy, total and particulate carbon (PC) concentrations in the IRG soils were significantly higher than those in the CON soils both in Jangheung and Seocheon where the IRG has been established for three years, whereas carbon concentrations were not significantly different in Cheonan where IRG planting history is only one year. In rice paddy soils, PC was suggested as an early indicator to monitor changes in soil carbon storage followed by adopting different management practices. In pasture, total and PC concentrations increased with duration period especially in the 0-5 cm soils. Contrary to the rice paddy soils, the magnitude of change in PC concentration is not as great as that in total carbon concentration, implying that there is a need to develop a new early indicator other than PC using different fractionation scheme. The soil carbon storage in pasture also increased with years since establishment and the increasing rate was significantly greater in the early stage (0-5 yrs) than the later one (> 5 yrs). Microbial activities measured from fluorescein diacetate (FDA) hydrolysis analysis were significantly lower in the IRG soils than CON soils, whereas no difference was observed in the pastures of different ages. This shows that FDA activity is not a sensitive indicator to differentiate soil qualities influenced by management practices if it is used by itself.

• Journal of Animal Environmental Science
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• v.11 no.3
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• pp.161-168
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• 2005

The disinfectants are important to prevention of infectious diseases for livestock and have been used widespreadly in recent years. This study was conducted to determine the effect of the disinfectants on microorganisms with reference to disinfectants concentration and application period in piggery slurry. As material, chemically different four disinfectants were used and no disinfectant, as control. These four disinfectants were Acids, Basic, Aldehydes and Alkalis, respectively. The characteristics pH, moisture content and organic matter of the piggery slurry used in this study were 8.2, $98.6\%,\;0.4\%$, respectively. The initial total microorganisms of piggery slurry were $6.3\times10^5$ cfu/ml, and Escherichia coli, Staphylococcus aureus, Bacillus cereus were $1.2\times10^4,\;4.1\times10^4,\;1.7\times10^4 cfu/ml,$ respectively. The disinfectants were applied at $100\%,\;200\%\;and\;300\%$ concentrations on the piggery slurry surface. It was determined that the effect of disinfectants varied accordance to concentration and application time. The most sensitive microorganisms were Escherichia coli and Staphylococcus aureus, while Bacillus cereus was found to be durable. As a result of this study, the microorganinsms of the piggery slurry are on the decrease by all disinfectants during 2 weeks, but showed a tendency to increase in number after that time. Accordingly, the microorganisms which are concerned in the liquid composting of piggery slurry were not affected by the disinfectant after 2 weeks.

• Journal of Astronomy and Space Sciences
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• v.20 no.4
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• pp.283-298
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• 2003

The 2001 Leonid meteor storm has been observed all over the world, and its most intense flux since the last few decades has caused great interest among both laymen and experts. Especially, its maximum hours occurred at dawn hours of Nov. 19 in the east Asia, during which moonless clear night at the Mt. Bohyun allowed us near perfect condition of observation. Observation was carried out in the period of 01:00∼05:40(KST), which include the predicted maximum hours, with all-sky camera installed for upper atmospheric airglow research. Tn this paper we analyze 68 all-sky images obtained in this period, which contain records of 172 meteors. Utilizing the zenith hourly rate(ZHR) of 3000 and magnitude distribution index of 2, which were reported to International Meteor Organization by visible observers in the east Asia, we estimate the limiting magnitude of about 3 for meteors detected in our all-sky images. We then derive magnitudes of 83 meteors with clear pixel brightness outlines among the initially detected 172 meteors by comparing with neighbor standard stars. Angular velocities of meteors needed for computing their passing times over an all-sky image are expressed with a simple formula of an angle between a meteor head and the Leonid radiant point. The derived magnitudes of 83 meteors are in the range of -6∼-1 magnitude, and its distribution shows a maximum new -3mag. The derived magnitudes are much smaller than the limiting magnitude inferred from the comparison with the result of naked-eye observations. The difference may be due to the characteristic difference between nearly instantaneuous naked-eye observations and CCD observations with a long exposure. We redetermine magnitudes of the meteors by adjusting a meteor lasting time to be consistent with the naked-eye observations. The relative distribution of the redetermined magnitudes, which has a maximum at 0 mag., resembles that of the magnitudes determined with the in-principle method. The relative distribution is quite different from ones that decrease monotonically with decreasing magnitudes for meteors(1∼6) sensitive to naked-eye observations. We conclude from the magnitude distribution of our all-sky observation that meteors brighter than about 0 mag., appeared more frequently during the 2001 Leonid maximum hours. The frequent appearance of bright meteors has significantly important implication for meteor research. We noted, however, considerably large uncertainties in magnitudes determined only by comparing standard stars due to the unknown lasting time of meteors and the non-linear sensitivity of all-sky camera.

• Neonatal Medicine
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• v.16 no.2
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• pp.172-181
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• 2009

Purpose: To identify trends in causative bacterial organisms for neonatal sepsis and antimicrobial susceptibilities over 10 years in one neonatal intensive care unit. Methods: We retrospectively reviewed the cases of culture-proven neonatal sepsis between January 1998 and December 2007. The 10-year period was divided into two phases (phase I, 1998-2002; phase II, 2003-2007) to distinguish the differences during the entire period. Results: Total 350 episodes of neonatal sepsis were identified in 315 neonates. The common pathogens of early-onset sepsis were S. epidermidis, S. aureus, P. aeruginosa, and E. cloacae in phase I, and S. epidermidis and E. cloacae in phase II. In cases of late-onset sepsis, coagulase negative Staphylococcus, S. aureus, and K. pneumoniae were isolated frequently in both phases. The incidence of sepsis caused by multi-drug resistant organisms decreased with strict infection control. Gram positive organisms showed 0-20% susceptibility to penicillin, ampicillin, and cefotaxime in both phases. Sensitivity to amikacin for Enterobacter spp. increased, whereas P. aeruginosa showed decreased sensitivity in phase II. Between 50% and 60% of other gram negative bacteria, except P. aeruginosa, were susceptible to cefotaxime in phase II in contrast to phase I. Greater than 80% of gram negative bacteria were sensitive to imipenem except P. aeruginosa and ciprofloxacin in both phases. Conclusion: The trend in causative microorganisms and antimicrobial susceptibilities can be used as a guideline for selection of appropriate antibiotics. A particular attention should be paid to infection control, especially to reduce sepsis caused by multi-drug resistant organisms.

• 한국해양학회지
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• v.14 no.1
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• pp.15-25
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• 1979

A study on field bioassay test using four species of commercially important shellfish was carried out to assess the effect of pollutants and determine the extent of marine environmental pollution of the Masan Bay from 9 to 15 August 1978. Water quality analysis and planktological examination of sea water were made during the experiment and the examination gave the following results. The water temperature was so high at 31.7$^{\circ}C$ in maximum and rather subject to change on weather condition of the land than on the effect of the water mass from outer bay. The range of DO,COD and SS at the stations were 0.3-7.08cc/l, 0.07-3.31ppm and 5.5-117ppm, respectively with the high values of COD and SS at the stations 7 and 1. The concentrations of the dissolved inorganic nitrogen in sea water, NH$\sub$4/-N, NO$\sub$2/-N, NO$\sub$3/-N, and PO$\sub$4/-P were 18.90-99.80, 2.48- 19.60, 13.00-39.00 and 1.04-14.0$\mu\textrm{g}$ at/l, respectively with decrease of their values in the outer part of the Bay. The high values mentioned above were caused by the sewage and industrial activities. The effects of organic waste are increased oxygen demand, nutrient concentration, turbidity and a higher input of pathogens, leading to structural changes in the marine ecosystems and to a considerable hazard to public health. The percentage composition of phytoplankton standing crop between diatom and dinoflagellate was characterized by making a difference between the two groups in respect of location: a decrease of diatom and a increase of dinoflagellate in numerical abundance toward inner part from outer part of the bay. Namely phytoplankton organisms were composed of 80% of diatom and 20% of dinoflagellate in outer bay, on the contrary, only 4% of diatom and 96% of dinoflagellate occupied by 94% of prorocentrum micans known as tolerant species to polluted reaas in the inner bay. On the occurrence and composition of zooplankton, there are two significant communities in the bay:one is characterized by the predominance of Oithona nana and the other by Favella sp They were composed of a range from 84% to 90% of the total organisms and monotonously constituted of themselves only at most inner station 3 even small numbers. From the results mentioned above, Oithona nana, Favella and prorocentrum micans recommed themselves as valuable indicators for judging the extent of the marine pollution.During the period of the biossays Mytilus edulis showed the highest mortality and Tapes japonica the lowest one between the four test species. The highest death rate by stations was found at most inner stations 3'and 4near Masan Free Export Zone with the most sensitive response and the lowest one occured at outer station 13 where no death specimen of oyster and arkshell was found during the whole test period.As for mussel,85 percent death rate appeared after 72 hours and 100percent rate after 120hours at station 4. It was found that the significant high mortality of the test shellfish mentioned above was caused by severe pollution with mainly organic pollutants from domestic sewage and industrial wastes from the results of too much higher concentrations of dissolved inorganic nitrogen especially ammonia-N,COD,SS and lack of dissolved oxygen,and furthermore occurrence and abundance composition of Prorcentrum,Favella and Oithona nana by stations, valuable indicator species of coastal pollution by orgnic and boilogical pollutants.

• Magazine of the Korean Society of Agricultural Engineers
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• v.19 no.1
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• pp.4323-4337
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• 1977

The study was to estimate the effect of the rise of water temperature in the warm water pool and to make contribution to the establishment of reducing to a damage of cool water as well as to the planning for warm water pool. This observation was performed in Wudu warm water pool located at Wudu-Dong of Chuncheon for two years from 1975 to 1976. The results were showed as follows; 1. The daily variation of water temperature was the least for inset (No.1; 0.6$^{\circ}C$) the second for middle overflow (No2: 3$^{\circ}C$, No.3; 2.3$^{\circ}C$) and another for outflet (No.4; 3.6$^{\circ}C$, No.5; 3.8$^{\circ}C$) And the highest reaching time of water temperature in each block was later about 1 hour than the time at which air temperature happend in the daytime. So, the variation of water temperature was sensitive to the variation of air temperature 2. The monthly variation of water temperature at each measuring point was plotted to be increased with increase in air temperature till August (Mean monthly rising degree; No.1; 1.15$^{\circ}C$, No.2; 1.7$^{\circ}C$, No.3; 1.73$^{\circ}C$, No.4; 2.08$^{\circ}C$, No.5; 2.0$^{\circ}C$), and expressed gradually descended influence upon water temperature after August. 3. The mean temperature of inflow folwed in warm Water pool was 7.5∼12.5$^{\circ}C$, and outflow temperature was described as 13.4∼22.5$^{\circ}C$ to be climbed. And So, the rising interval of water temperature was shown as 6.7∼10.4$^{\circ}C$. 4. The correlation between the rising of water temperature and the weather condition was found out highly significant. As the result, their correlation coefficents of water temperature depending on mean air temperature, ground temperature, wind velocity and relative humidity were to be 0.93, 0.90, - 0.83 and 0.71 respectively. But there was no confrimation of the correlation on the clouds, sunlight time, volume of evaporation, and heat capacity of horizontal place. 5. The water temperature of balance during the period of rice growing in Chuncheon district was shown as table 10, and the mean of whole period was calculated as about 23.7$^{\circ}C$. 6. The observed value of the outflow temperature passed through the warm water pool was higher than that of computed, the mean difference between two value was marked as 1.15$^{\circ}C$ for blockl, 1.18$^{\circ}C$ for block2, and 0.47$^{\circ}C$ for block3, respectivly. Therefore, the ratio on the rising degree between the observed and computed were shown as 53%, 44%, and 18%, mean 38% through each block warm water pool (referring item $\circled9$ of table 11,12, and 13). Accordingly, formula (4) in order to fit for each block warm water pool was transfromed as follow; {{{{ { theta }_{w } - { theta }_{ 0} =[1-exp LEFT { { 1-(1+2 varphi )} over {cp } CDOT { A} over { q} RIGHT } ] TIMES ( { theta }_{w } - { theta }_{ 0}) TIMES C }}}} Here, correction coefficinent was computed 1.38, and being substituted 1.38 for C in preceding formula, the expected water temperature will be calculated to be able to irrigate the rice paddy. As the result, we can apply the coefficient in order to plan and to construct a new warm water pool.

• Korean Journal of Environmental Biology
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• v.31 no.4
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• pp.393-401
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• 2013

The objectives of this study were to analyze structures of fish community and the ecological health using a multi-metric fish model, the Index of Biological Integrity (IBI) in the Backje Weir of Geum River during two periods namely before-the-fishkill ($B_f$) and after-the-fishkill ($A_f$). The total number of fish species observed were 32 and among them 10 species (35%) were Korean endemic species. The exotic species observed were 3 which decreased by 0.4% after-the-fishkill ($A_f$). The dominant species were Opsariichthys uncirostris amurensis (13%) at the Bf period and Squalidus japonicus coreanus (17%) at the Af period in the Backje Weir. At after the fishkill ($A_{f-I}$) total biomass was about 10 times lower than the biomass before-the-fishkill ($B_f$). The biomass of Carassius auratus decreased 98% after-the-fishkill and as time passed by the biomass recovered to nearly 100%. Similar decrease in the biomass occurred in the population of Opsariichthys uncirostris amurensis, while Rhinogobius brunneus population increased. According to the structure analysis of fish community, species richness index, evenness index and species diversity index were high but after-the fishkill, the values of indices decreased. Tolerant species (64%) dominated the fish community, and the sensitive species (2%) were rare, indicating the degradation of the ecosystem. According to analysis of the multi-metric model (IBI), the mean model value of the fish community in Backje Weir was estimated as 17.5 indicating a "fair condition".