• Journal of Korean Society of Environmental Engineers
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• v.22 no.10
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• pp.1881-1891
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• 2000

Cenosphere particles of different fly ash formed at the pulverized coal power plant were hollow sphere or filled with small particles inside solid particles. And size was relatively larger than other fly ash particles as well as specific gravity was small to suspend in the water. In this paper, it was demonstrated to contain a variety of morphological particle type, and the physical and chemical properties related to the cenosphere and fly ash particles. Furthermore it was estimated the possibility to reuse the cenosphere particles on the base of cenosphere properties. Cenosphere formation resulted from melting of mineral inclusion in coal, and then gas generation inside the molten droplet. As the aluminosilicate particle was progressively heated, a molten surface layer developed around the solid core. Further heating leaded to cause the formation of fine particles at the core. The mass median diameter(MMD) of cenosphere particles was $123.11{\mu}m$ and the range of size distribution was $100{\sim}200{\mu}m$ with single modal. It was represented that specific density was $0.67g/cm^3$ fineness was $1135g/cm^3$. The chemical components of cenosphere were similar to other fly ash including $SiO_2$, $Al_2O_3$, but the amount of the chemical component was different respectively. In the case of fly ash, $SiO_2$ concentration was 54.75%, and $Al_2O_3$ concentration was 21.96%, so this two components was found in 76.71% of the total concentration. But in the case of cenosphere, it was represented that $SiO_2$ concentration was 59.17% and $Al_2O_3$ concentration was 30.16%, so this two components was found in 89.33% of the total concentration. Glassy component formed by the aluminosilicate was high in the cenosphere, so that it was suitable to use insulating heat material.

• Journal of Korean Society on Water Environment
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• v.32 no.3
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• pp.261-270
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• 2016

We analyzed cyanobacterial community including akinete, resting cell, and benthic cyanobacteria in sediment of Bukhan, Namhan-River, Paldang-Lake, and Kyeongan-Stream and compared the physicochemical factors for water and pore water. We also performed cyanobacteria growth potential test through incubating sediment. As a result of physicochemical analysis, the concentrations of nutrients were similar for each depth of Bukhan-River. For Namhan-River and Lake Paldang sites, the concentrations of TP and DTN in bottom and deep water had higher levels. DTN in water body composed of NO3-N(73%) while DTN in pore water composed of NH3-N(77.8%). Benthic cyanobacteria in the sediment such as Oscillatoria tenuis, O. limosa, Phormidium tenue, Pseudanabaena limnetica, and Lyngbya sp. were dominant (between 0.0∼243.3×10³ cells/g, w/w). Cell densities of cyanobacteria in sediment depth of 0∼2 cm in most sites were higher compared to those in other depths. The cell density of cyanobacteria in sediment correlated with pH, conductivity, BOD5, TP, DTP, and chl. a. Increased phytoplankton and organic matters were found to be able to inhibit the growth of benthic cyanobacteria. Results of cyanobacteria growth potential test after incubating sediment revealed that harmful cyanobacteria (Anabaena, Aphanizomenon, Microcystis, and Oscillatoria) appeared at 7 days post culturing. Base on these results, the methods used in this study are considered to be able to determine the appearance of harmful cyanobacteria.

• Journal of Acupuncture Research
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• v.21 no.1
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• pp.119-135
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• 2004

Objective: The purpose of this study is to investigate the mechanism and effect of moxibustion with salt objectively, to be used as the quantitative data through the measurement of temperature, and to grasp the thermodynamic characteristics of moxibustion with salt. Methods: We have selected of the moxibustion with salt of indirect moxibustion. We make a comparative study of the thermodynamic characteristics of moxibustion with salt as a kind of the 4 salt. We examined combustion times, temperatures, temperature gradients in each period during a combustion of moxa. Results: 1. We make out that it is not significantly change the time of thermal conduction of moxibustion with salt as a kind of 4 salt. 2. The heating period of Refined Salt was long and that of Sun-dried Salt was a short time respectively. The heating period of maximum tamperature is high Sun-dried Salt, Mechanical Salt and Refined Salt orderly. Maximun heating speed in the heating period was $0.151{\sim}0.184^{\circ}C/sec$ and at the same tendency of the maximum temperature in the heating period. 3. The retaining period was shorter than the heating period respectively, that is 15~24% of the combustion time of in the heating period. We make out that it is not significantly different the time of the retaining period as a kind of 4 salt. The mean temperature of retaining period was $43.2{\sim}48.1^{\circ}C$, that was extraordinarily high temperature. 4. We make out that it is not significantly different the time of the cooling period as a kind of 4 salt. The cooling period was measured 223~233sec. Beacuse the same density and size of moxa combustion was made an experiment. 5. The effective combustion time of Refined Salt is longer(259sec) than that of Sun-dried Salt(173sec). It is significantly different the time of the combustion time as a kind of 4 salt. 6. It is significantly different the Sample deviation of the combustion time as a kind of 4 salt because of the water content of the 4 salt individually. Conclusions: As the base on this study, we obtained the conclusion as the follows. The salt of moxibustion with salt was fitted for Sun-dried Salt due to making to Mechanical Salt recently. The Refined Salt is composition rate to another and small size comparatively. So It was fitted for the salt of moxibustion with salt. It is necessary to study continuously about the more suitable moxibustion with salt and quantitative analysis about the moxibustion with salt.

• Journal of Forest and Environmental Science
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• v.36 no.3
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• pp.175-186
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• 2020

This study approaches, from a floristic perspective, the under-researched human-primate competition for forest resources. Investigating the human impact on fruit trees edible for Kinda baboons (Papio kindae Lönnberg), we have collated dietary data on a free-ranging troop and floristic information on two forest sites of the Kundelungu National Park (KNP), Democratic Republic of Congo: the relatively intact Integral Zone (IZ) and the human-disturbed Annex Zone (AZ). Trees with DBH≥10 cm have been identified, counted and measured throughout 22 sample plots (11 per site), each measuring 1,000 ㎡. A total of seven woody species whose fruits are eaten by Kinda baboons were recorded. Four of them, namely the Sycamore fig Ficus sycomorus L., the Mobola plum Parinari curatellifolia Planch. ex Benth, the Kudu berry Pseudolachnostylis maprouneifolia Pax and the Monkey orange Strychnos innocua Delile were found in both sites, while the Large-leaved jackal-berry Diosyros kirkii Hiern and the Buffalo thorn Ziziphus mucronata Willd. were exclusively in the IZ, and Strychnos cocculoides Baker only in the AZ. Compared to the IZ, the AZ had lower values of stem density, species richness and diversity indices, suggesting a negative human impact on baboon-edible trees, in line with our hypothesis. Moreover, as was expected, human activities decreased the abundance of larger baboon-edible fruit trees. However, the size-class distribution of P. curatellifolia depicted a reverse J-curve in the AZ. The abundant younger P. curatellifolia trees remaining in that human-disturbed site constitute an important food stock for baboons, if well preserved. These results also illustrate the critical role of rangers' patrols, formerly more frequent (and presumably efficient) in the IZ than in the AZ of the Park. Their implications on baboons and miombo forests are discussed from both the research and conservation perspectives.

• Journal of The Korean Association For Science Education
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• v.19 no.2
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• pp.256-265
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• 1999

The purpose of this study is to investigate the relationship between cognitive levels and achievement of science process skills. A science laboratory process skills test based on optional instrument of the SISS was administered to a sample of 162 students in the 8th grade. Practical assessment tasks consisted of the contents about acid, base, density, and a property of cobalt chloride. The format of this practical test was the station type that students had to conduct a short activity. Science process skills included three sub-skills which were categorized as designing, performing, and reasoning. As cognitive levels develop from concrete operational stage to transition stage and formal operational stage. total scores of science process skills and mean scores of sub-skills were significantly increased. Regardless of cognitive levels. all students were more successful on performing than designing or reasoning. In case of being controlled cognitive levels, gender differences and area differences were not detected in achievement of science process skills. According to these results. there was a strong relationship between cognitive levels and achievement of science process skills by practical assessment. This study implies that considering student's cognitive levels is very important for improving science process skills.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7757-7761
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• 2014

Aim: To report long term outcomes of laser conization for high grade cervical intraepithelial neoplasia (CIN) in Thai women. Materials and Methods: A retrospective cohort study was conducted in patients undergoing laser conization due to abnormal cervical cytology suggesting neoplasia during 1989 to 1994 and having follow-up data until December 2010. Conization was performed under colposcopy using a 0.5-mm $CO_2$ laser beam with power density of $18,000-20,000watts/cm^2$, and the surgical base was vaporized using a low power defocused beam. The follow-up protocol included cervical cytology and colposcopy. Long term outcome measures were failure rate (persistence and recurrence), post-conization status of transformation zone, and obstetric outcomes. Results: Of 104 patients undergoing conization, 71 had therapeutic conization for high grade CIN and were followed up for a median time of 115 (range 12-260) months. There was one case of persistent and one of recurrent disease comprising a failure rate of 2.8%. The post treatment transformation zone was well visualized in 68.3% of 63 patients with an intact uterus. Sixteen patients achieved 25 pregnancies; none had second trimester miscarriage. The obstetric outcomes were unremarkable. Conclusions: Laser conization under colposcopic visualization for the treatment of high grade CIN in Thai women has a low failure rate of 2.8%. The post-conization transformation zone could not be evaluated completely in approximately 30% of cases; therefore the follow-up protocol should include both cytology and colposcopy. Obstetric outcomes are not adversely affected by this therapeutic procedure.

• Korean journal of applied entomology
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• v.32 no.3
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• pp.307-316
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• 1993

The potential of using GIS in analyzing pest surveillance data was explored. The Spatial Analysis System (SPANS) was used to construct a spatial data base to study pest distributions using pest surveillance data collected from 152 stations in South Korea. The annual spatIal distributions of the striped rice borer(SRB), Chdo suppressalis, showed that high densities started to expand in the early 1980s, reaching a peak in 1988. The pattern change appears to be related to cultivation of japonica and indica-japonica hybrid varieties in South Korea. Japo7l!ca varieties have longer duration resulting in the SRB haVlng more time to mature and hibernate in wmter. The locus of SRB spread appears to be located in the mid-west region near lri, Chun~ Buk Province. High brown planthopper (BPH) populations in South Korea are often related to the early immigration and temperature. The simulated distribution of PPH densities in September using these two factors was compared with the actual distribution obtained using 1990 data. The two density maps corresponded closely excepL for differences in the south eastern valley. By overlaying the simulated map layer with the elevation and rice area maps, more specific BPH risk zones could be identified.

• Fire Science and Engineering
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• v.23 no.4
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• pp.32-39
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• 2009

In this study, 18 plots were selected for particular investigation on Gangneung area and Samcheok area and Uljin area, where forest fire was occurred after thinning in 2007. After selection, a relationship between a damage of forest fire and thinning were compared and analyzed. Many factor such as a damaged species, a thinning or non-thinning, a direction of forest fire head, DBH, a height of tree, a mortality of tree, a leeward scorching ratio, a crown damage ratio, a forest tree standing crop density, a crown base height, a leaving of thinning slash, a location of plot (GPS), elevation, an aspect of slope, an angle of slope, and a topography were measured. Therefore, we analyzed a relationship with forest fire. In the result of this analysis, it was founded that the leeward scorching ratio was 24.7% on thinning area whereas 60.2% on non-thinning area. Subsequently, leeward scorching ratio on thinning area was increased by about 35.5% more than on non-thinning area. In the result of analysis about tree species, a forest of pine tree was more damaged than forest of oak tree. The mortality of tree was increased by about 41.4% on non-thinning area. When stands were close to thinning slashes, these were more damaged by 10${\sim}$20% than other stands for increasing of amount of a combustion material. Especially, as potential of re-ignition increased for more cumulated thinning slash, it will be more important to require a method for a periodical removing or practical utilization of slash.

• Conservation Science in Museum
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• v.16
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• pp.82-95
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• 2015

Old Monk by Yun Duseo is realized to use silver paper which is made of rarity material. This sudy investigates reason why silver, that is easily discoloration in environmental condition, is susceptible in present. The method was the surface treatment materials and the base fiber through direct observation, optical instruments and XRF analysis. Based on these results, reproducing experiment was conducted to research materials in paper of Old Monk and the surface treatment technique. The results, the paper was treated 'Dochim' with a mineral having polygonal crystals for improving smoothness and density. XRF analysis result showed high calcium content, therefore, the paper was not used silver, it guess pulverized shells of abalone or other types of shellfish. Accordingly, the research was narrowed down to shells with shiny, reflective surfaces which at the same time contain high amounts of calcium. A new experiment was conducted using unprocessed abalone shells. Through the reproducing experiment, shellfish has high possibility as used mineral in paper. Notwithstanding, this experiment was unable to precisely reproduce the smoothness and shine of the original paper. Further research may therefore be needed.

• Membrane Journal
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• v.30 no.5
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• pp.307-318
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• 2020

Conventional perfluorinated sulfonic acid membrane, Nafion is widely used for vanadium redox flow battery (VRFB). It is desired to prevent vanadium ion permeation through a membrane to retain the capacity, and to keep the cell efficiency of a VRFB. Highly proton conductive and chemically stable Nafion membranes, however, suffer from high vanadium permeation, which induce the reduction in charge and discharge capacity by side reactions of vanadium ions. In this study, to resolve the issue, silica nanoparticles, which are functionalized with 3-aminopropyl group (fS) are introduced to enhance the long-term performance of a VRFB by lowering vanadium permeation. It is expected that amine groups on silica nanoparticles are converted to positive ammonium ion, which could deteriorate positively charged vanadium ions' crossover by Gibbs-Donnan effect. There is reduction in proton conductivity may due to acid-base complexation between fS and Nafion side chains, but ion selectivity of proton to vanadium ion is enhanced by introducing fS to Nafion membranes. With the composite membranes of Nafion and fS, VRFBs maintain their discharge capacity up to 80% at a high current density of 150 mA/㎠ during 200 cycles.