Fish fauna and lentic ecosystem health assessment in freshwater were analyzed in the two reservoirs (Uirim Reservoir(Ur) and Solbangjuk Reservoir(Sr)) of the Jecheon City during May-September 2017. Total numbers of the species and genus (7 family) sampled were 21 and 16, respectively. Cyprinidae was most dominant taxa, which accounted for 11 species (52.4%) of the total species, and the relative abundance, based on the number of individuals, was 318 individuals (46.2%). Subdominant families were taxa of Centrachidae (2 species; 264 ind. (38.4%). The dominant species, based on the relative abundance, were Squalidus chankaensistsuchigae(22.7%). Subdominant species were Lepomis macrochirus(19.5%, 134 ind.) and Micropterus salmoides(18.9%, 134 ind.). Trophic state index of Korea ($TSI_{KO}$), based on chemical oxygen demand (COD), total phosphorus (TP) and chlorophyll-a (CHL),ranged mesotrophic state. The purpose of this study was to apply a multi-metric model of Lentic Ecosystem Health Assessments (LEHA) for environmental impact assessments of two reservoirs and assessed the ecological health model values. Trophic composition's metrics showed that tolerant species (56.8%, 98.3%) and omnivore species (43.9%, 65.6%) dominated the fish fauna in the two reservoirs (Ur and Sr) of Jecheon City, indicating a biological degradation in the aquatic ecosystem. The relative proportions of Micropterus salmoides, also showed greater than 16.3% (Ur), 31.1% (Sr) of the total, indicating a ecological disturbance. The average value of LEHA model was 22 (Ur) and 12 (Sr) in the reservoirs, indicating a "poor condition (Ur)" and "very poor condition (Sr)" by the criteria of MOE (2014).
This study was to analyze the ecological conditions, based on physical habitat, chemical, and biological conditions before (2006, 2007) and after ecological restoration (2009) in five sites of Changwon Stream (CS) and six sites of Nam Stream (NS), respectively, and then to compare ecological health between the two period. The analysis of ecological health was based on the multimetric models of Index of Biological Integrity (IBI) and Qualitative Habitat Evaluation Index (QHEI) along with water chemistry in the streams. For the study, the models of IBI and QHEI were modified as 8 and 11 metric attributes, respectively. For the evaluations, the survey was conducted in the period of 2006~2007 before the restoration and in 2009 after the restoration by the city. Chemical conditions, based on conductivity, in both streams showed a typical longitudinal declines along the axis of the upstream-to-downstream. There were no significant differences (p>0.05) in water quality between the two periods. Values of IBI in the CS and NS averaged 21.6 and 19.7, respectively, indicating a C grade in the criteria of Ministry of Environment, Korea, and there was no significant differences in the IBI between the two periods. Values of QHEI after the restoration averaged 29.2 and 63.2 in the CS and NS, respectively and the values decreased markedly especially, in the NS (35.3) after the restoration. The habitat disturbance was mainly attributed to destructions (i.e., the narrower width of riparian vegetation and higher substrate exposure by the air) of artificial materials by massive flood in 2009. Overall, our results suggest that the restoration was not effective in the two streams between the two periods, even if the budget was used a lot and that such ecological restoration, not considered the natural disaster, may not effect for the stream restoration.
Journal of the korean academy of Pediatric Dentistry
/
v.34
no.1
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pp.91-98
/
2007
The aim of this study was to examine the difference of the depth of sedation using the Bispectral index assessment with and without the added submucosal Midazolam to oral Chloral hydrate and Hydroxyzine for pediatric patients. Twenty seven sedation cases were performed in this study Selection criteria included good health(ASA I), 2 to 6 years of age, the need for sedation to receive dental treatment including anesthesia, and restorative procedure over at least two teeth. Patients were randomly classified into one group taking oral Chloral hydrate(60 mg/kg) and Hydroxyzine(1 mg/kg) and the other group recieving Chloral hydrate(60 mg/kg), Hydroxyzine(1 mg/kg) and submucosal Midazolam(0.1 mg/kg). Nitrous Oxide(50%) was used for both group during sedation. Patients were monitored using a pulse oximeter and a Bispectral monitor. A behavior scale was rated as quiet(Q), crying(C), movement(M), or struggling(S) every 2 minutes watching a recorded videotape. Analysis showed a significant difference in mean Bispectral index and SD during sedation across two groups(P<0.001). The group of patients injected with submucosal Midazolam in addition to oral Chloral hydrate and Hydroxyzine showed a lower mean Bispectral index and a narrower SD. PR and SpO2 for both groups remained within the normal values. Submucosal Midazolam improved the sedation quality by deepening sedation depth without compromising safety and enabled the sedation pattern to be kept more stable.
Olive oil and grape seed oil (10% of meat weight) were added to a package of beef loin. The package was then vacuum-sealed, and high pressure was applied (HP, 600 MPa) to investigate the effect of the penetration of vegetable oil into meat and safety and quality of the meat. Non-HP (0.1 MPa) without any oil treatment was considered as a control. The color $L^*$ and $b^*$-values of beef loin were higher and the $a^*$-value was lower than those of the control after HP at 600 MPa. The total aerobic bacterial number was 3 Log CFU/g in the control but no viable cell was detected in the beef with 600 MPa. All inoculated E. coli and L. monocytogenes were inactivated by HP. The beef loin with vegetable oil added without HP did not show any difference in fatty acid composition, but that treated by HP showed a higher oleic and linoleic acid content when olive oil and grape seed oil were added, respectively. The addition of olive oil inhibited lipid oxidation, and sensory evaluation revealed that there was no difference among treatments. The results indicate that the addition of vegetable oil followed by the application of HP enhances the safety of beef loin, changing the fatty acid composition in a health beneficial way. In addition, the use of olive oil can inhibit lipid oxidation induced by HP.
Stream inflows induced by flood runoffs have a higher density than the ambient reservoir water because of a lower water temperature and elevated suspended sediment(SS) concentration. As the propagation of density currents that formed by density difference between inflow and ambient water affects reservoir water quality and ecosystem, an understanding of reservoir density current is essential for an optimization of filed monitoring, analysis and forecast of SS and nutrient transport, and their proper management and control. This study was aimed to quantify the characteristics of inflow density current including plunge depth($d_p$) and distance($X_p$), separation depth($d_s$), interflow thickness($h_i$), arrival time to dam($t_a$), reduction ratio(${\beta}$) of SS contained stream inflow for different flood magnitude in Daecheong Reservoir with a validated two-dimensional(2D) numerical model. 10 different flood scenarios corresponding to inflow densimetric Froude number($Fr_i$) range from 0.920 to 9.205 were set up based on the hydrograph obtained from June 13 to July 3, 2004. A fully developed stratification condition was assumed as an initial water temperature profile. Higher $Fr_i$(inertia-to-buoyancy ratio) resulted in a greater $d_p,\;X_p,\;d_s,\;h_i$, and faster propagation of interflow, while the effect of reservoir geometry on these characteristics was significant. The Hebbert equation that estimates $d_p$ assuming steady-state flow condition with triangular cross section substantially over-estimated the $d_p$ because it does not consider the spatial variation of reservoir geometry and water surface changes during flood events. The ${\beta}$ values between inflow and dam sites were decreased as $Fr_i$ increased, but reversed after $Fr_i$>9.0 because of turbulent mixing effect. The results provides a practical and effective prediction measures for reservoir operators to first capture the behavior of turbidity inflow.
Kim, Bu-Kyung;Lee, Dong-In;Kim, Jeong-Chang;Lee, Jun-Ho
Journal of the Korean earth science society
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v.33
no.6
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pp.469-480
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2012
This study was to analyze the characteristics of diurnal variation of high $PM_{2.5}$ concentration, $PM_{2.5}/PM_{10}$ concentration ratio by spatio-temporal wind system (wind speed and wind direction) for high $PM_{2.5}$ concentration (over the 24 hr environmental standard of $PM_{2.5}$, $50{\mu}g/m^3$) in the air quality observation sites (Jangrimdong: Industrial area, Jwadong: Residential area) that were measured for 3 years (2005. 12. 1-2008. 11. 30) in Busan. The observation days of high $PM_{2.5}$ concentration were 182 at Jangrimdong and 27 at Jwadong. The seasonal diurnal variation of hourly mean of high $PM_{2.5}$ concentration and of $PM_{2.5}/PM_{10}$ concentration ratio showed a similar pattern that had higher variation at dawn, and night and in the morning than in the afternoon. Durning daytime in summer at Jwadong, the $PM_{2.5}/PM_{10}$ concentration ratio increased because a secondary particulate matter, which was created by photochemical reaction, decreased the coarse particles of $PM_{10}$ more than the fine particles of $PM_{2.5}$ concentrations in ocean condition. We did an analysis of spatio-temporal wind system (wind speed range and wind direction) in each time zone. The result showed that high $PM_{2.5}$ concentration at Jangrimdong occurred due to the congestion of pollutants emissions from the industrial complex in Jangrimdong area and the transportation of pollutants from places nearby Jangrimdong. It also showed that high $PM_{2.5}$ concentration occurred at Jwadong because of a number of local residential and commercial activities that caused the congestion of pollutants.
Korean Journal of Agricultural and Forest Meteorology
/
v.19
no.4
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pp.280-292
/
2017
Hail is not a frequently occurring weather event, and there are even fewer reports of hail damages to forest stands. Since the 2000s, an increase in hail incidence has been documented in Europe and the United States. In Korea, severe hails occurred in Jeollanam-do province on May 31 and in Gyeongsangbuk-do province on June 1, 2017. Hail size was ranged from 0.5 to 5.0 cm in diameter in Jeollanam-do, and from 1.5 to 3.0 cm in Gyeongsangbuk-do. This study was aimed to analyze the hail damages to forests by species and topography based on damage-categorized maps created by using drones and aerial photographs, and to analyze relationships of the damages with meteorological factors. The total damaged forest area was 1,163.1ha in Jeollanam-do, and 2,942.3ha in Gyeongsangbuk-do. Among the 'severe' damaged area 326.7ha, 91% was distributed in Jeollanam-do, and concentrated in the city of Hwasun which covers 57.2% of the total 'severe' damaged area. The most heavily damaged species was Korean red pine(Pinus densiflora S. & Z.) followed by P. rigida. Most broad-leaved trees species including oaks were recovered without any dead trees found. Liliodendron tulipifera was the most severely damaged in terms of the rate of 'severe' degree individuals which are needed to be checked whether they will die or be recovered. Cause of the death of pines was considered as the combination of physical damage caused by the hail and long-lasting drought with high air temperature that occurred before and after the hail event. No pathogens and insects were found which might have affected to tree deaths. We suggested a dieback mechanism of the pine trees damaged by hail and drought.
This study analyzed physical and chemical characteristics of peat soil to use peat soil as the materials fur pot media and investigated seedling quality of horticultural plants in order to use peat soil as the raw materials fur pot media. The summary of the results is as follows; The chemical characteristics of peat soil, which is main ingredient of pot media are as follows; pH was 4.9, EC was less than $2.0ds{\cdot}m^{-1}$, which interferes the growth of the plant and organic ingredient was 33%. When looking into the germination characteristics of plants according to the mixture of pot media, red pepper showed 54.2% speed of germination and 97% germination rate in peat soil single treatment. Therefore the peatsoil was appropriate for the pot media for red pepper. In case of cucumbers, in the 50 : 50 treatment of main ingredient (peat soil) and auxiliary ingredients (vermiculite, peat moss and perlite) they showed 100% speed of germination and 100% germination rate. Therefore 50 : 50 treatment was appropriate fur the pot media for cucumbers. In case of chinese cabbage, peat soil, perlite and peat moss mixture (50 : 25 : 25) treatment showed the highest speed of germination (77.5%), while the germination rate was a little lower (92.15%) than comparative soil. However, it was appropriate for the pot media for chinese cabbage. In case of watermelon, germination was bad because of the influence of EC when the teat soil ingredient is over 80%. However, in the mixture of peat soil and vermiculite (50:50) treatment, they showed 91.6% speed of germination and 100% germination rate. Therefore it was appropriate for the pot media for watermelon. When looking into the growth of the plants according to the mixture of ingredients, peat soil and perlite (50:50) mixture showed excellent seedling quality for cucumbers, peat soil and perlite (50:50) mixture showed excellent seedling quality and it was proven to be appropriate for the pot media for cucumbers. In case of watermelon, peat soil, peat moss and perlite (80 : 10 : 10) mixture showed excellent seedling quality and it was proven to be appropriate for the pot media for watermelon.
Journal of the Korea Academia-Industrial cooperation Society
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v.17
no.10
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pp.591-599
/
2016
Among the employer-supported subscribers to the National Health Insurance Service, 6,797 people with mild disabilities with western ages of 20 and up and who received health checkups were investigated. Of these 6,797 people, 3,186 and 3,611 received health checkups in 2009 and 2013, respectively. Those people who were diagnosed with physical handicaps, brain lesions, visual impairment, hearing impairment, intellectual disabilities, mental disorders, kidney disorders or other disorders according to the classification standard for people with disabilities were classified into disability groups of the 3rd through 6th degrees. The purpose of this study was to examine the dangerous influence of obesity of people with mild disabilities on their hyperglycemia, hypertension and high cholesterol. The items measured in this study were abdominal obesity, body mass index, fasting glucose, total cholesterol, systolic blood pressure and diastolic blood pressure. To look for connections between the obesity level and at-risk groups for each disease, cross tabulation and multinomial logistic regression analyses were utilized. Higher levels of abdominal obesity and BMI were found among those who were male, were younger and had higher incomes. The risks of abdominal obesity and BMI were higher in the abnormal groups for each disease. In 2009, the obesity group whose BMI was higher had a 1.51-fold higher risk of hypertension than the normal group. The abdominal obesity group had a 1.59-fold higher risk of high cholesterol, a 1.26-fold higher risk of hypertension and a 1.54-fold higher risk of hyperglycemia than the normal group. In 2013, the obesity group whose BMI was higher had a 1.72-fold higher risk of high cholesterol and a 1.43-fold higher risk of hypertension than the normal group. Those with abdominal obesity had a 1.59-fold higher risk of hyperglycemia than the normal subjects. As the risk of obesity was higher in those with disabilities than in those without disabilities, the former should be encouraged to undergo health checkups on a regular basis, and the coverage of the health checkups should be extended to keep track of their illness. In addition, appropriate education and concern are both required to prevent obesity.
The purpose of this study was to investigate the effects of composite resin restorations on the stress distribution of notch shaped noncarious cervical lesion using three-dimensional (3D) finite element analysis (FEA). Extracted maxillary second premolar was scanned serially with Micro-CT (SkyScan1072 ; SkyScan, Aartselaar, Belgium). The 3D images were processed by 3D-DOCTOR (Able Software Co., Lexington, MA, USA). ANSYS (Swanson Analysis Systems, Inc., Houston, USA) was used to mesh and analyze 3D FE model. Notch shaped cavity was filled with hybrid or flowable resin and each restoration was simulated with adhesive layer thickness ($40{\mu}m$) A static load of 500 N was applied on a point load condition at buccal cusp (loading A) and palatal cusp (loading B). The principal stresses in the lesion apex (internal line angle of cavity) and middle vertical wall were analyzed using ANSYS. The results were as follows 1. Under loading A, compressive stress is created in the unrestored and restored cavity. Under loading B, tensile stress is created. And the peak stress concentration is seen at near mesial corner of the cavity under each load condition. 2. Compared to the unrestored cavity, the principal stresses at the cemeto-enamel junction (CEJ) and internal line angle of the cavity were more reduced in the restored cavity on both load con ditions. 3. In teeth restored with hybrid composite, the principal stresses at the CEJ and internal line angle of the cavity were more reduced than flowable resin.
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