• Journal of Korean Society of Environmental Engineers
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• v.35 no.7
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• pp.509-517
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• 2013

The purpose of this study is to assess the applicability of device-type stream coagulation process which combines physiochemical, biological processing for efficient improvement of water quality in small, middle-sized urban streams. The stream purification facility of this study is compose of pressure flotation type Micro Bubble Process(MBP) to remove TSS and TP and conduit line type Attached Microbial Pipe System(AMPS) to remove BOD. Test conditions of each device were set by floating stay time and change of ultra fine bubble injection amount of MBP, and change of AMPS stay time. Also, removal efficiency of pollution sources of each process were assess by change of season. As result of continuous operation of each process, MBP showed a maximum of TSS 83.69%, TP 95.15% process efficiency and AMPS showed a maximum of 52.95% TBOD5 removal efficiency. Also as result of circular operation of each process, MBP showed a maximum of TSS 69.75%, TP 70.17% process efficiency and AMPS showed a maximum of 68.58% TBOD5 removal efficiency. Therefore, it is considered that this stream coagulation process is effective in improving the water quality of streams in urban areas.

• Journal of Acupuncture Research
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• v.21 no.2
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• pp.1-20
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• 2004

Objective : The aim of this study was to investigate effects of Angelica gigas Nakai(AGN) on the ischemic injury by intraluminal filament insertion in the rats. Methods : The ischemia was induced by intraluminal filament insertion into middle cerebral artery. AGN herbal acupuncture into SP10 was carried out during 3 weeks after ischemic injury. Eight-arm radial maze was designed for the behavioral task. AGN herbal acupuncture showed neuroprotective agents in cresyl violet, acetylcholinesterase(AchE), choline acetyltransferase(ChAT) and nerve growth factor(NGF)-stain. Then check the effect of regional cerebral blood flow(rCBF) according to AGN herbal acupuncture in rats. Results : The errors in the eight-arm radial maze task were significantly decreased in normal group compared with control group on 1~6days, AGN2(0.02g/kg) herbal acupuncture group on 1~5days, AGN3(0.1g/kg) on 1~3days, AGN4(0.5g/kg) on 1, 3~6days. The rate of correct choice was significantly increased in AGN1(0.01g/kg) and AGN4 herbal acupuncture groups. The density of neurons in the hippocampal CA1 was the most increased in normal group and AGN1, AGN3, AGN4 herbal acupuncture groups compared with control group. The density of AchE in the hippocampal CA1 had a tendency to increase in all the groups when they were compared with control group, but not significant. The density of ChAT in the hippocampal CA1 was significantly increased in normal group and AGN1, AGN4 herbal acupuncture groups compared with control group. The density of NGF in the hippocampal CA1 was significantly increased AGN4 herbal acupuncture group compared with control group. The rCBF was significantly increased in AGN1, AGN3 and AGN4 herbal acupuncture groups without the change of blood pressure. Conclusions : These results suggest that AGN herbal acupuncture can be used for controlling stroke in early stage as herbal medication.

• Economic and Environmental Geology
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• v.45 no.5
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• pp.535-549
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• 2012

Main aspect of this study are to clarify mineral compositions on granites in Youngkwang-Naju area. These granites are is divided into four rock facies based on the geologic ages, mineralogical composition and chemical constituents, and texture : hornblende-biotite granodiorite, biotite granite, porphyritic granite and two mica granite. These granites constitude an igneous complex formed by a series of differentiation from cogenetic magma. In compressive stress field between the Ogcheon folded belt and the Youngnam massif, the foliated and undeformed granites had formed owing to heterogeneous distribution of stress. The geochemical data of study area indicate magma of these rocks would had been generated by melting in lower and middle crust. The major minerals of granitic rocks in study area are plagioclase, biotite, muscovite and hornblende. Plagioclase range in composition from oligoclase ($An_{19.3-27.7}$) to andesine ($An_{28.4-31}$), and shows normal zoning patterns, This uniformed composition indicated slow crystallization, and it is obvious that the growth of these crystal occurred before final consolidation of the magma. The Mg content of biotite are increases with increasing of $f_{O2}$ and grade of differentiation, changing from phlogopite to siderophyllite. Its $Al^{iv}$/$Al^{total}$ ratios are propertional to bulk rock alumina content. Muscovite is primary in origin with high content of $TiO_2$, and Its composition correspond to celadonitic muscovite. Hornblende indicated calc amphibole group ($(Ca+Na)_{M4}{\geq}1.43$, $Na_{M4}<0.67$). and consolidation pressure of granitic body by geobarometer of Hammerstrume and Zen show 11.3~17.2 Km.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.6
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• pp.1714-1721
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• 2004

This experimental study was designed to investigate the mechanism of Palmul-Tang(PMT) on the changes of cerebral hemodynamics in rats. The changes of cerebral hemodynamics in normal rats were as follows ; The PMT-induced increase in regional cerebral blood flow was significantly inhibited by pretreatment with indomethacin(1㎎/㎏, i.p.), an inhibitor of cyclooxygenase, and was inhibited by methylene blue(10㎍/㎏, i.p.), an inhibitor of guanylate cyclase. The PMT-induced dilation in pial arterial diameter was significantly inhibited by pretreatment with indomethacin and methylene blue. The PMT-induced increase in mean arterial blood pressure was significantly inhibited by pretreatment with indomethacin but was increased by methylene blue. This results were suggested that the mechanism of PMT was mediated by cyclooxygenase. The changes of cytokine production in cerebral ischemic rats were as follows ; In cytokine production of serum by drawing from femoral arterial blood after middle cerebral arterial occlusion 1hr, sample group was decreased IL-1β and TNF-α production compared with control group, IL-10 production of sample group was similar to that of control group, but sample group was significantly increased TGF-β production compared with control group. In cytokine production of serum by drawing from femoral arterial blood after reperfusion 1hr, sample group was significantly decreased IL-1β production compared with control group and decreased TNF-α production compared with control group. IL-10 production of sample group was similar to that of control group, but sample group was significantly increased TGF-β production compared with control group. In cytokine production of serum by drawing from femoral arterial blood after reperfusion 4 hrs, sample group was significantly decreased IL-1β production compared with control group, but IL-10 production of sample group was similar to that of control group. sample group was increased TNF-α and TGF-β production compared with control group. These results suggested that PMT had inhibitive effect on the brain damage by inhibiting IL-1β and TNF-α production, but by accelerating TGF-β production. The present author thought that PMT had an anti-ischemic effect through the improvement of cerebral hemodynamics and inhibitive effect on the brain damage.

• Journal of Preventive Medicine and Public Health
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• v.32 no.4
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• pp.435-442
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• 1999

Objectives: The purpose of this study was to examine the twelve-year incidence of hypertension, and to find risk factors for the incidence in adult population in Kangwha County, Korea. Methods: In 1986, 413 males(mean age 37 years) and 434 females(mean age 33 years) were examined in the Kangwha Study, Among 764 non-hypertensive participants, 164 males and 214 females were reexamined in 1998. Blood pressure(BP) was measured with standard mercury sphygmomanometers. Multiple logistic regression analysis was used to estimate the relative risk of risk factors on the incidence of hypertension. Results: During the 12-year period, 68 of 164 males and 53 of 2f4 females developed hypertension. In a multiple logistic model adjusted for age and pulse rate, baseline BP, baseline body mass index(BMI) and BMI change during the follow-up period were significantly related to the incidence of hyperiension. Adjusted relative risk(RR)s of baseline high-normal BP were 3.90(95% CI: 1.81-7.84) in males, and 12.72(95% CI: 3.70-30.73) in females. Compared with lower baseline BMI group, adjusted RRs of middle baseline BMI group were 2.66(95% CI: 1.19-5.70) in males, and 2.33(95% CI: 0.95-5.55) in females. Adjusted RRs of upper baseline BMI group were 3.52(95% CI: 1.53-7.67) in males and 3.63(95% CI: 1.50-8.43) in females. Increase of BMI was positively related to the incidence in males(adjusted RR=2.71, 95% CI: 1.00-6.71) and females(adjusted RR=3.05, 95% CI: 1.29-6.88). Conclusions: The twelve-year incidence of hypertension was 41.5% in males, and 25.8% in females. Baseline BP, baseline BMI, and BMI change were strongly related to the incidence of hypertension.

• Magazine of the Korean Society of Agricultural Engineers
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• v.31 no.2
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• pp.82-91
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• 1989

This study was carried out to get the basic information of irrigation plans for the red pepper, such as optimum irrigation level and irrigation requirement in Taegu and Kyungpook province. In this study, red peppers were cultivated in 6 PVC pot lysimeters filled with 60cm deep clay loam soil. Four tensiometers were installed in each plot to measure the soil water pressure head. Field measurements were made during the period June 6 to October 31, 1988 at the experimental farm of Kvungpook National University. Six levels of irrigation were used. They were PF 1.8-2.0, PF 2.2-2.4, PF 2.8-3.0, FC-PF.1.7, FC-PF 2.2, and FC-PF 2.7. The results obtained from this study are summarized as follows : 1. In case of irrigation levels of narrow ranges of water contents, the higher the soil water content was, the larger the ET was. Hut in case of the irrigation levels returning to the field capacity, the lager the PF value of irrigation point was, the larger the ET was. Considering ET, yield and weight per fruit, the latter is much better than the former irrigation method. 2. The mean daily ET and mean ET ratio for each 10-day period showed that the maximum value occured in the last of August. The ranges of those were 3.74-14.64 mm/day and 0.87-3.40, respectively. These values showed that small during the early stage of growth, large during the middle stage and getting smaller in the last stage. 3. In case of irrigation levels of narrow ranges of water contents, the increase of irrigation water supplied increased the ET. The relationship between the two showed nearly straight line. Most of irrigated water was consumed as ET and the rest as percolation. But, in case of irrigation levels returning to the field capacity, the higher the PF value of irrigation point was, the larger the ET ratio was. However, their relationship didn't show straight line. 4. The irrigation level of PC - PP 2.7 was found to be the optimum irrigation level with respect to the yield, the weight per fruit, stem length, irrigation requirement and percolation quantity. In this case, mean daily ET and mean ET ratio were 6.79 mm/day (total 10052 mm) and 1.67, respectively. The maximum mean daily ET and mean ET ratio for 10-day period were 14.64 mm/day and 3.40, respectively, in the last of August, and the maximum daily ET was 2126 mm/day on August 24. 5. In case of PC - PP 2.7 which is found the optimum irrigation level, mean irrigation water required, mean ET and mean percolation water quantity were 7.44 mm/day, 6.79 mm/day(91.3% of irrigation water), and 0.38 mm/day (5.5% of it), respectively.

• Journal of The Korean Association For Science Education
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• v.30 no.8
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• pp.1044-1059
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• 2010

In this study, we investigated the influences of the method of using analogy on concept understanding, mapping understanding, and mapping error by analogical reasoning ability level. We also investigated students' perception of a role-playing analogy activity. Seventh graders (N=152) at a middle school were assigned to the comparison and the experimental groups. The students of the experimental group were taught about 'the relation between pressure and volume of gas' with experience-based role-playing analogy, while those of the comparison group were taught with explanation-centered analogy. Analyses of the results revealed that the instruction using roleplaying analogy was more effective in concept understanding and retention of mapping understanding than explanation-centered analogy instruction, regardless of analogical reasoning ability level. It was also found that the students of the experimental group had fewer mapping errors than those of the comparison group. However, there was little difference in t pes of mapping errors by the method of using analogy. The students of the experimental group answered that they did not have difficulties in performing the role-playing analogy activity and they actively engaged in the activity. They perceived that the role-playing analogy activity was interesting. Educational implication of these findings are discussed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.2 no.2
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• pp.49-56
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• 2001

The possibility of a noise reduction of piezoelectric single Panels is experimentally studied. Piezoelectric single panel is basically a plate structure on which piezoelectric patch with shunt circuit is mounted. The use of piezoelectric shunt damping can reduce the transmission at resonance frequencies of the panel structure. Piezo-damping is implemented by using a newly proposed tuning method. This method is based on electrical impedance model and maximizing the dissipated energy at the shunt circuit. By measuring the electrical impedance at the piezoelectric patch bonded on a structure, an equivalent electrical model is constructed near the system resonance frequency. Resonant shunt circuit for piezoelectric shunt damping is composed of register and inductor in series, and they are determined by maximizing the dissipated energy throughout the circuit. The transmitted noise reduction performance of single Panel is tested on an acoustic tunnel. The tunnel is a tube with a square cross section and a loud speaker is mounted at one side of the tube as a sound source. Panels are mounted in the middle of the tunnel and the transmitted sound pressure across Panels is measured. By enabling the piezoelectric shunt damping noise reduction is achieved at the resonance frequencies as well. Piezoelectric single panel with piezoelectric shunt damping is a promising technology for noise reduction in a broadband frequency.

• Tunnel and Underground Space
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• v.28 no.2
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• pp.170-185
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• 2018

The effect of fault on the stability of the closely-spaced twin tunnels located in fault zones was investigated by numerical analyses and scaled model tests on condition of varying widths, inclinations and material properties of fault. When obtaining the strength/stress ratios of pillar between twin tunnels, three different stresses were used which were measured at the middle point of pillar, calculated to whole average along the pillar section and measured at the left/right edges of pillar. Among them, the method by use of the left/right edges turned out to be the most conservative stability estimation regardless of the presence of fault and reflected the excavating procedures of tunnel in real time. It was also found that the strength/stress ratios of pillar were decreased as the widths and inclinations of fault were increased and as the material properties of fault were decreased on condition using the stresses measured at the left/right edges of pillar. As a result of scaled model tests, it was found that the model with fault showed less crack initiating pressure than the model without fault. As the width of fault was larger, tunnel stability was decreased. The fault had also a great influence on the failure behavior of tunnels, such as the model without fault showed failure cracks generated horizontally at the left/right edges of pillar and at the sidewalls of twin tunnels, whereas the model with fault showed failure cracks directionally generated at the center of pillar located in the fault zone.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.3
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• pp.655-668
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• 1994

Conventional deodorization filters using soil and compost reach the capacity limitation of deodorization in short period, because its removal mechanism primarily depends on adsorption. Therefore, in this study the experiment was performed on the removal of ammonia which is a strong inorganic malodor, frequently emitted from night soil treatment plants and sewage treatment plants, by seeding activated sludges on the bio-peat containing higher organic contents, water conservation capacity, permeability and lower pressure drop. As a result, in raw peat filter natural ammonia outlet was observed in consequence of pH increase resulted from ammonia ionizing in liquid phase. Ammonia removal mechanism primarily depended on the adsorption onto the anion colloidal substances in peat. In peat bio-filter, theoretical ammonium salts ratio was higher than that of raw peat, resulted from slight pH increase by microorganism activity, however, the experimetal value of ammonia-nitrogen accumulated in bio-peat was lower than that of raw peat because of nitrification by nitrifying bacteria. In the initial reaction period, adsorption was predominant in the ammonia removal mechanism, but nitrification was conspicuous after the middle period. Mass balance of nitrogen was established using experimental data of input $NH_3$ loading, output $NH_3$ loading, $NH_4{^+}$-N, $NO_x$-N, and Org-N. The critical time of unsteady state, which is the maximum activating point of microorganism in bio-filter, was determined using experimental data, and the ammonia adsorption curve was computed using regression analysis. On the basis of the results obtained by above analysis, the delay days for the saturation of adsoption capacity in peat bio-filter was calculated.