• Journal of Korean Society of Environmental Engineers
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• v.27 no.12
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• pp.1249-1256
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• 2005

This study was performed to investigate the efficiency of the corrosion prevention in the simulated distribution system using CCPP(Calcium Carbonate Precipitation Potential) as the anti-corrosive index by adjusting pH, total dissolved solids, alkalinity and calcium hardness in the water treatment pilot process. The materials of the simulated distribution system(SDS) were equiped with same materials of real field water distribution system. CCPP concentrations controlled by $Ca(OH)_2$, $CO_2$ gas and $Na_2CO_3$ in the simulated distribution system and uncontrolled by the chemicals in the general water distribution system were average 0.61 mg/L and -7.77 mg/L. The concentrations of heavy metals like Fe, Zn, Cu ions in effluent water of the simulated distribution system controlled with water quality were decreased rather than the general water distribution system uncontrolled with water quality. In simulated distribution system(SDS), corrosion prevention film formed by CCPP control was observed that scale was come into forming six months later and it was formed into density as time goes on. We were analyzed XRD(X-ray diffraction) for investigating component of crystal compounds and structure for galvanized steel pipe(15 mm). Finding on analysis, scale was compounded to $Zn_4CO_3(OH)_6{\cdot}H_2O$ (Zinc Carbonate Hydroxide Hydrate) after ten months late, and it was compounded on $CaCO_3$(Calcium Carbonate) and $ZnCO_3$(Smithsonite) after nineteen months later.

• Journal of Korean Society of Forest Science
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• v.28 no.1
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• pp.1-20
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• 1975

F$\ddot{u}$r die Erforschllng der Variationen bei der Naturpopulationen der Pinus densifiora wurden drei Populationen aus Chuwangsan (Kyong-buk), Anmyondo (Chung-nam) und Odaesan (Kangwon) Ausgewiiblt. Bei je 20 Individuen jeder Population wurden die Variationen von der Eigenschaft der $\ddot{a}$usseren Gestalt, von der anatomischen und morphologischen Eigenschaft der Kiefernadel und von der Holzqualit$\ddot{a}$t an Bohrsp$\ddot{a}$nen untersucht. Das Ergebnis der Untersuchung konnte in den folgenden sechs Punkten formuliert werden. 1. Von den Eigenschaften der $\ddot{a}$usseren Gestalt ist die Geradheit des Baumstamms, der Durchmesser der Zweige und der Winkel der Verzweigung in der Odaesan Population wlinschenswerter als in anderen Populationen. 2. Es wird festgestellt, dass sich die drei Nadelmerkmale, Anzahl der Z$\ddot{a}$hne je 0.5 cm, Anzahl der Stomata-Reihen und Anzahl der Harzkan$\ddot{a}$le, sowohl zwischen den Populationen als auch zwischen den Individuen signignifikant unterscheiden. 3. Bei der Betrachtung des Harzkanal Index, der Schichtanzahl der Hypodermis und der Entfernung der Fibrovasalb$\ddot{u}$ndel wird aufgezeigt, dass sich alle drei gepr$\ddot{u}$ften Populationen geringf$\ddot{u}$gig von der normalen Kiefer unterscheiden. 4. Zwischen den Populationen ergibt sich ein Unterschied im Prozentanteil des Spatho lzes und im spezifischen Geswicht, jedoch zeigt die Breite der Jahresrings und die Tracheidenl$\ddot{a}$nge keinen Unterschied. Das spezifische Gewicht und die Tracheidenl$\ddot{a}$nge der Individuen jeder Population ist signifikant verschieden. 5. Bei dem Alter 11-20 ist der Prozentanteil des sp$\ddot{a}$tholzes am gr$\ddot{o}$ssten und wird aber danach immer geringer bis zum Alter 30; sp$\ddot{a}$ter zeigt sich dann keine sichtbare Ver$\ddot{a}$nderung mehr. Das spezifische Gewicht sich vergr$\ddot{o}$ssert bei der Zunahme des Jahresrings, nimmt aber dann in Anmyondo und Odaesan Populationen beim Alter 21-30 wieder ab. Die Tracheidenl$\ddot{a}$nge der drei Populationen besitzen die Neigung, sich nach der zunahme der Jahresringe zu vermehren. 6. Mit diesen hier behandelten Charakteren werden ganz allgemeinen die Unterschiede der drei Kiefer populationen festgestellt. Diese Ergebnisse sind sehr bemerkenswert betrachtet vom genetischen Gesichtspunkt der waldbaumpopulation.

• Journal of the Korean earth science society
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• v.38 no.3
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• pp.194-208
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• 2017

This study analyzed the correlation between tropical cyclone (TC) frequency and the western North Pacific monsoon index (WNPMI), which have both been influential in East China Sea during the summer season over the past 37 years (1977-2013). A high positive correlation was found between these two variables, but it did not change even if El $Ni{\tilde{n}}o$-Southern Oscillation (ENSO) years were excluded. To determine the cause of this positive correlation, the highest (positive WNPMI phase) and lowest WNPMIs (negative WNPMI phase) during an eleven-year period were selected to analyze the mean difference between them, excluding ENSO years. In the positive WNPMI phase, TCs were mainly generated in the eastern seas of the tropical and subtropical western North Pacific, passing through the East China Sea and moving northward toward Korea and Japan. In the negative phase, TCs were mainly generated in the western seas of the tropical and subtropical western North Pacific, passing through the South China Sea and moving westward toward China's southern regions. Therefore, TC intensity in the positive phase was stronger due to the acquisition of sufficient energy from the sea while moving a long distance up to East Asia's mid-latitude. Additionally, TCs occurred more in the positive phase. Regarding the difference in 850 hPa and 500 hPa stream flows between the two phases, anomalous cyclones were strengthened in the tropical and subtropical western North Pacific, whereas anomalous anticyclones were strengthened in East Asia's mid-latitude regions. Due to these two anomalous pressure systems, anomalous southeasterlies developed in East China Sea, which played a role in the anomalous steering flows that moved TCs into this region. Furthermore, due to the anomalous cyclones that developed in the tropical and subtropical western North Pacific, more TCs could be generated in the positive phase.

• Sleep Medicine and Psychophysiology
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• v.10 no.1
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• pp.32-38
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• 2003

Objectives: The purpose of this study is to investigate the effects of stress and personality on sleep patterns, and further, to identify potential correlations between stress and personality characteristics. Methods: A total of 174 healthy college students were subjects for this study. Participants filled out the Daily Stress Inventory before sleep and the Modified Pittsburgh Sleep Quality Index after sleep on three consecutive days. They also filled out the 16 Personality Factor Questionnaire (16-PF), BDI (Beck Depression Inventory) and STAI (State-Trait Anxiety Inventory). Results: Minor stresses highly correlated with subjective sleep quality and symptoms of non-restorative sleep. However, total sleep time, sleep latency, awakening frequency, and frequency of dreams were not explained by stress scores. The O (guilty feeling), C (low ego strength) and Q4 (high anxiety) factors of the 16-PF also highly correlated with symptoms of non-restorative sleep and significantly affected sleep patterns. BDI and STAI scores also correlated with the above personality factors and minor stresses. Conclusion: This study showed that minor stresses impaired the restorative effects of sleep. Personality characteristics such as low ego strength, high levels of anxiety, and feelings of guilt were vulnerable to minor stresses. Minor stress, various personality characteristics, different coping patterns, and emotional response are highly correlated with each other and affect sleep patterns.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.664-671
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• 2019

This study was conducted to investigate the environmental impact of the construction of the Yeongju Dam, located near the upper stream of the Nakdong River, on benthic macroinvertebrates. The investigation was conducted four times from 2015 to 2016 and the composition of the benthic macroinvertebrate fauna from the four surveyed sites was compared. After the dam construction, the number of benthic macroinvertebrate species decreased and the species composition ratio of the E.P.T taxa(Ephemeroptera, Plecoptera, and Trichoptera) decreased, which favored the previous environment and the large riverbed structure. However, the species composition ratio of the O.C.H taxa (Odonata, Coleoptera, and Hemiptera), which favored the reservoir environment, increased. For the pattern of changes in the functional habitat groups, the proportion of 'Clinger(CL)' taxa decreased and the 'Burrower(BU), Climber(CB), Sprawler(SP), Swimmer(SW)' taxa increased in all surveys after the dam construction. A cluster stability comparison showed that the 'Stability Group II' species of St.2 and St.3 showed a drastic decrease. The average Benthic Macroinvertebrate Index(BMI) of all the survey sites in 2016 was lower than that in 2015. This research confirmed the temporal and spatial changes in the habitat type and community structure of the benthic macroinvertebrates resulting from the dam construction.

• The Journal of Engineering Geology
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• v.8 no.3
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• pp.247-259
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• 1998

Groundwater quality of the natural mineral water was investigated in hydrochemical aspects in order to ensure that mineral water meets stringent health standards. There exist 20 mineral water plants in the Daebo granite and 4 mineral water plants in the Bulguksa granite, respectively. Both granite areas show some differences in water chemistry. The pH, EC, hardness, total ionic contents in groundwater of the Daebo granite area are higher relative to those of the Bulguksa granite area. The content of major cations is in the order of Ca>Na>Mg>K, while that of major anions shows the order of $HCO_3>SO_4$>Cl>F. The fact that the $Ca-Na-HCO_3$ type is most predominant among water types may reflect that the dissolution of plagioclase that is most abundant in granitic rocks plays a most important role in groundwater chemistry. Representative correlation coefficients between chemical species are variable depending on geology. In the Daebo granite area, $Ca-HCO_3(0.84),{\;}Mg-HCO_3(0.81),{\;}SiO_2-Cl(0.74),{\;}Na-HCO_3(0.70)$ show relatively good correlationships. In the Bulguksa granite area, fairly good correlationships are found among some components such as K-Mg(0.93), $K-HCO_3(0.92)$, Mg-Cl(0.92), $Cl-HCO_3(0.91)$, and K-F(0.90). According to saturation index, most chemical species are undersaturated with respect to major minerals, except for some silica phases. Groundwater is slightly undersaturated with respect to calcite, whereas it is still greatly undersaturated with respect to dolomite, gypsum and fluorite. Based on the phase equilibrium it is clear that groundwater is mostly in equilibrium with kaolinite and becomes undersaturated with respect to feldspars, evolved from the stability area of gibbsite during water-rock interaction. While the activity of silica increases, there is no remarkable increase in the acivities of alkali ions and pH, which indicates that some amounts of silicic acid dissolved from silica phases as well as feldspars were provided to groundwater. It is concluded that chemical evolution of groundwater in granite aquifers may continue to proceed with increasing pH.

• Clinics in Shoulder and Elbow
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• v.12 no.2
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• pp.159-166
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• 2009

Purpose: We wanted to evaluate the surgical results of early mobilization after rigid fixation of small coronoid fracture using the tension band technique Materials and Methods: Eight cases of coronoid fracture were fixed with the tension band technique and using K-wire and wire through the medial approach. All the cases were Regan-Morrey type 2. According to O'Driscoll, they were classified as 5 cases of the tip type (subtype 2) and 3 cases of the anteromedial type (1 case of subtype 2, and 2 case of subtype 3). The associated collateral ligament injuries (6 cases) and radial head/neck fractures (4 cases) were managed simultaneously. After immobilization for 5~7 days, active ROM exercise with a fitted hinge brace started and continued till postoperative 6 weeks. The patients were assessed for pain, ROM and functional disability using the Mayo elbow performance score (MEPS) at an average of 11 months (range: 6~28 months). The ulnar nerve symptoms were also investigated. Results: We observed solid union in all the coronoid fractures without hardware failure. An average of 2.2 wires (range: 2~4) were used. The mean extension was $3^{\circ}$(range: $0^{\circ}\sim25^{\circ}$), the mean flexion was $137^{\circ}$(range: $130^{\circ}\sim140^{\circ}$), the mean pronation was $69^{\circ}$(range: $45^{\circ}\sim90^{\circ}$) and the mean supination was $78^{\circ}$(range: $45^{\circ}\sim90^{\circ}$). The mean MEPS was 96 (range: 65~100). Ulnar nerve symptoms occurred at postoperative one day and persisted in one patient with the terrible triad of taking radial head excision and residual medial instability. Conclusion: The tension band technique uses easily obtained, economic K-wires and the wire was strong enough to permit early elbow ROM exercise and the technique might improve the elbow function. It was especially useful for fixation of multiple small fragments.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.347-352
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• 2011

Environment-friendly agriculture (EFA) are aimed to reduce use of chemical inputs as possible the recycling of resources and the environment while preserving the local resources in the long term to ensure a constant productivity and profitability for producing safe food. This study was conducted to investigate characteristics on soil environment at paddy field of environment-friendly agriculture regions (EFARs) in Honam area. Survey point of EFARs Chungnam, Jeonbuk and Jeonnam, rice bran farming method in two districts, rice bran + snail farming method in eight districts, snail farming method in five districts and ducks farming method in three districts a total of 18 districts were selected. Annual of farming method, friendly-environment certification, amount of applied fertilizer, and history of cultivation to the farm household were surveyed. The content of available phosphate and silicate among the soil chemical properties in EFA paddy field were a little lower than optimum level, and those of agricultural methods fertilized with rice bran were a little lower than those of others. Hardness among the soil physical properties in EFA paddy field were a little lower than conventional practices, and that of agricultural methods fertilized with rice bran were a little lower than those of others. We showed fertilizer recommendation dose about soil nutritional shortages according to fertilization prescriptions index by crops.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.1
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• pp.41-51
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• 1991

This study was conducted to determine the effect of 20 years long term fertilizations on the physical and chemical properties of paddy soil and the growth, yield, yield components and grain development of rice. Non-fertilized, PK, NK, NP, NPK, NPK + compost, NPK+straw and NPK+lime have been applied since 1968 after surface paddy soil was removed. NPK+compost and NPK+straw applications increased the content of organic matter, available P and CEC, and lime increased soil acidity and SiO$_2$ content. While chemical contents in non-fertilized treatment were low as compared with other treatments. Soil porosity was higher in NPK+straw (51.4%) and NPK+lime(53.1%) than in NPK application (49.8%). Soil hardness was highest in the NPK application and was lowest in the NPK + lime. Continuous application of straw with NPK markedly increased the content of aggregate with over 1mm(19.6%) as compared with NPK application (7.1%). Plant height, tiller number, root number, leaf area index and total dry weight were higher in the applications of compost, straw and lime with NPK than in any other treatments. Brown rice yield in non-fertilized, PK and NP applications was decreased 45, 55, 15 and 5% of that in NPK application, respectively, while application of compost, straw and lime with NPK increased the yield by 11, 14 and 4%, respectively, during 20 years. The number of differentiated rachis branchs in the application of compost, straw and lime was 17 to 21 and that in the other application was 13 to 15, whereas the degenerated rachis branchs was low in the application of compost, straw and lime with NPK. The applications having higher level of perfect rice grain such as non-fertilized, NPK+compost, NPK+straw and NPK+lime had high grain weight and had low level of white core rice, white belly rice. The white core and belly rice was highest in the NP application and notched belly rice kernel was markedly increased in NK and NP applications. The period of grain filling was 30 DAH at NP and NPK applications, 35 DAH at NK and NPK+lime, 40DAH at NPK+compost and NPK+ straw, and 45DAH at non-fertilized, respectively.

• Tuberculosis and Respiratory Diseases
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• v.47 no.6
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• pp.824-835
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• 1999

Background: Sleep-related breathing disorders are commonly found in patients with chronic renal failure and particularly, sleep apnea may have an influence on the long-term mortality rates in these patients. Maintenance hemodialysis is the mainstay of medical measures for correcting the metabolic derangements of chronic renal failure but it is uncertain whether it may alleviate sleep disorders including sleep apnea. Methods: Forty seven patients on maintenance hemodialysis were surveyed with the sleep questionnaire about their clinical symptoms related to sleep disorders. Among them, 15 patients underwent the polysomnography and their blood levels of urea nitrogen, creatinine, electrolytes and the arterial blood gases in the nights before and following hemodialysis were measured. Results: Forty(85.1%) of the 47 patients complained of the symptoms associated with sleep-wake cycle disturbances, 55.3% experienced snoring and 27.7% reported witnessed apneas. The duration of REM sleep increased significantly in the nights after hemodialysis compared to the nights without hemodialysis(p<0.05) and the percentage of total sleep time comprising NREM sleep decreased significantly in the nights following hemodialysis compared to the nights before hemodialysis(p<0.05). The percentage of total sleep time consisting of the stage 1 and 2 NREM sleep showed the trend for a decrease in the nights after hemodialysis(p=0.051), while the percentage of total sleep time comprising the stage 3 and 4 NREM sleep did not change between nights. The obstructive sleep apnea was more predominant type than the central one in both nights and there were no differences in the apnea index and the apnea-hypopnea index between the nights. The decrease in the blood level of urea nitrogen, creatinine, potassium and phosphorus was observed after hemodialysis(p<0.05), but the differences of parameters measured during polysomnography between the nights did not correlate with the changes of biochemical factors obtained on the two nights. Arterial blood gas analysis showed that pH was significantly greater in the nights after hemodialysis than in the nights before hemodialysis(p<0.05), but there were no correlations between the parameters examined during polysomnography and the parameters of arterial blood gas analysis(p<0.05). Conclusion: These results suggest that chronic renal failure is an important systemic disorder which is strongly associated with sleep disorders. Maintenance hemodialysis, although it is a widely accepted measure to treat chronic renal failure, did not significantly modulate the sleep architecture and the severity of sleep apnea. Thus, taking the patients with chronic renal failure into account, it is advisable to try not only to find a substantial way for correcting metabolic derangements but also to consider the institution of more effective treatments for sleep disorders.