• Steel and Composite Structures
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• v.37 no.1
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• pp.91-98
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• 2020

Steel plate shear walls are recently used as efficient seismic lateral resisting systems. These lateral resistant structures are implemented to provide more strength, stiffness and ductility in limited space areas. In this study, the seismic behavior of the multi-story steel frames with steel plate shear walls are investigated for buildings with 4, 8, 12 and 16 stories using verified computational modeling platforms. Different number of steel moment bays with distinctive lengths are investigated to effectively determine the deflection amplification factor for low-rise and high-rise structures. Results showed that the dissipated energy in moment frames with steel plates are significantly related to the inside panel. It is shown that more than 50% of the dissipated energy under various ground motions is dissipated by the panel itself, and increasing the steel plate length leads to higher energy dissipation capability. The deflection amplification factor is studied in details for various verified parametric cases, and it is concluded that for a typical multi-story moment frame with steel plate shear walls, the amplification factor is 4.93 which is less than the recommended conservative values in the design codes. It is shown that the deflection amplification factor decreases if the height of the building increases, for which the frames with more than six stories would have less recommended deflection amplification factor. In addition, increasing the number of bays or decreasing the steel plate shear wall length leads to a reduction of the deflection amplification factor.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.12
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• pp.4873-4880
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• 2015

Purpose: To describe the clinicopathological features of gastrointestinal stromal tumors (GIST) diagnosed in our section and to perform risk stratification of our cases by assigning them to specific risk categories and groups for disease progression based on proposals by Fletcher et al and Miettinen and Lasota. Materials and Results: We retrieved 255 cases of GIST diagnosed between 2003 and 2014. Over 59% were male. The age range was 16 to 83 years with a mean of 51 years. Over 70% occurred between 40 and 70 years of age. Average diameter of tumors was 10 cms. The stomach was the most common site accounting for about 40%. EGISTs constituted about 16%. On histologic examination, spindle cell morphology was seen in almost of 85% cases. CD117 was the most useful immunohistochemical antibody, positive in 98%. Risk stratification was possible for 220 cases. Based on Fletcher's consensus proposal, 62.3 gastric, 81.8% duodenal, 68% small intestinal, 72% colorectal and 89% EGISTs were assigned to the high risk category; while based on Miettinen and Lasota's algorithm, about 48% gastric, 100% duodenal, 76% small intestinal, 100% colorectal and 100% EGISTs in our study were associated with high risk for disease progression, tumor metastasis and tumor related death. Follow up was available in 95 patients; 26 were dead and 69 alive at follow up. Most of the patients who died had high risk disease and on average death occurred just a few months to a maximum of one to two years after initial surgical resection. Conclusions: Epidemiological and morphologic findings in our study were similar to international published data. The majority of cases in our study belonged to the high risk category.

• Journal of the Korean Society of Tobacco Science
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• v.29 no.2
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• pp.98-103
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• 2007

This study compares menthol migration from fillers to filters and mainstream smoke in a type of leaf tobacco and according to the moisture content differences at the range of $11{\sim}15\;%$. The leaf tobacco used in this study consisted of Korea flue cured upper leaves B1O (KFUB1), A40R (KFUA4), lower leaves C1L (KFLC1), CD4L (KFLCD4), burley upper leaves A3T (KBUA3), lower leaves D3W (KBLD3), Orient Basma I/III (OB), Orient Izmir BIG (OI), expanded tobacco (KET), and reconstituted sheet (KRC). Menthol migration to the filter and mainstream was measured under constant conditions for 80 days with intervals of 20 days. In the comparison between flue cured types, there were significant differences in the filter parts, as follows. KFUB1(34.4 %) KFUA4(37.4 %), KFLC1(43 %) and KFLCD4 were 55.7 %. In the comparision between other types of leaf tobaccos, KFUB1 was 34.4 % and KET was 52.6 % at filter parts. In the methol transfer to mainstream smoke was $16.5{\sim}24.2\;%$. The menthol migration to filters was measured based on the moisture content of $11{\sim}15\;%$ for the KFUB1 after storing it for 80 days. The menthol migrations were $36{\sim}40\;%$ at the moisture content of $11{\sim}15\;%$, respectively. The transfers to mainstream smoke were $12.8{\sim}15.8\;%$.

• Journal of Environmental Science International
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• v.27 no.2
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• pp.109-122
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• 2018

This study was conducted to investigate the removal characteristics of heavy metals and sulfate ion from acid mine drainage by porous zeolite-slag ceramics (ZS ceramics) that was prepared by adding wood flour as pore-foaming agent while calcining the mixtures of natural zeolite and converter slag. The batch test showed that the removal efficiency of heavy metals by pellet-type porous ZS ceramics increased as the particle size of wood flour was decreased and as the weight mixing ratio of wood flour to ZS ceramics was increased. The optimal particle size and weight mixing ratio of wood flour were measured to be $75{\mu}m$ and 7~10%, respectively. The removal test with the porous ZS ceramics prepared in these optimal condition showed very high removal efficiencies: more than 98.4% for all heavy metals and 73.9% for sulfate ion. Relative to nonporous ZS ceramics, the increment of removal efficiency of heavy metals by porous ZS ceramics with $75{\mu}m$ and 10% wood flour was 5.8%, 60.5%, 36.9%, 87.7%, 10.3%, and 57.4% for Al, Cd, Cu, Mn, Pb, and Zn, respectively. The mechanism analysis of removal by the porous ZS ceramics suggested that the heavy metals and sulfate ion from acid mine drainage are eliminated by multiple reactions such as adsorption and/or ion exchange as well as precipitation and/or co-precipitation.

• Journal of Sasang Constitutional Medicine
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• v.16 no.2
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• pp.84-98
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• 2004

1. Objectives Yangkyuksanhwa-tang is used mush in pruritus and dermatopathy of Soyangin. It is suggested this prescription is effective on atopy dermatitis. 2. Methods For observation of Yangkyuksanhwa-tang effected to atopic dermatitis, extract of Yangkyuksanhwa-tang has been dispensed to the stratum corneum of epithelium in dermatome of murine after making damage to its defense mechanism against fat and causing atopic dermatitis artificially. After that, the change in outer dermatome and minute mechanism of epidermis, the change of eosinophil, the change in distribution of soybean agglutinin, the change in distribution of fat and ceramide in stratum corneum, the change in inflammation in dermatome, the change of cell accrementition and apoptosis, and the effect on anaphylaxis and Staphylococcus aureus was observed. 3. Results After administration of Yangkyuksanhwa-tang, severe skin damage such as eczema and psoriasis, that was observed in the case of atopy dermatitis, was decreased and the increase of eosinophil in serum was suppressed. Lipid lamella was recovered, so epidermal demage was relieved. The distribution of HSP70 in the outer skin was decreased. Yangkyuksanhwa-tang suppressed activation of $NF-_{\kappa}B$ p50, induced CD11/18b not to be generated, and suppressed inflammatory response of skin. Anaphylaxis and groth of Staphylococcus aureus was suppressed. 4. Conclusions Yangkyuksanhwa-tang decreased skin damage of atopy dermatitis. It has antibiosis about Staphylococcus aureus, it can be medicinal substances on atopy dermatitis. In addition, it is possible that it can be medicinal substances on regional skin allergy.

• Journal of Korean Society of Water Science and Technology
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• v.26 no.6
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• pp.13-26
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• 2018

This research was conducted to elucidate the removal mechanism of heavy metals and sulfate ion from acid mine drainage(AMD) by porous zeolite-slag ceramics (ZS ceramics) packed in a column reactor system. The average removal efficiencies of heavy metals and sulfate ion from AMD by the 1:3(Z:S) porous ZS ceramics in the column reactor under the HRT condition of 24 hours were Al 97.5%, As 98.8%, Cd 86.1%, Cu 96.2%, Fe 99.7%, Mn 64.1%, Pb 97.2%, Zn 66.7%, and $SO_4{^{2-}}$ 76.0% during 121 days of operation time. The XRD analysis showed that the ferric iron from AMD could be removed by adsorption and/or ion-exchange on the porous ZS ceramics. In addition it was known that Al, As, Cu, Mn, and Zn could adsorb or coprecipitate on the surface of Fe precipitates such as schwertmannite, ferrihydrite, or goethite. The EDS analysis revealed that Al, Fe, and Mn, which were of relatively high concentration in the AMD, would be adsorbed and/or ion-exchanged on the porous ZS ceramics and also exhibited that Al, Cu, Fe, Mn, and Zn could be precipitated as the form of metal hydroxide or sulfate and adsorbed or coprecipitated on the surface of Fe precipitates. The microscopic results on the porous ZS ceramics and precipitated sludge in a column reactor system suggested that the heavy metals and sulfate ion from AMD would be eliminated by the multiple mechanisms of coprecipitation, adsorption, ion-exchange as well as precipitation.

• Journal of Microbiology and Biotechnology
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• v.31 no.2
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• pp.290-297
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• 2021

Leptolyngbya sp. KIOST-1 (LK1) is a newly isolated cyanobacterium that shows no obvious cytotoxicity and contains high protein content for both human and animal diets. However, only limited information is available on its toxic effects. The purpose of this study was to validate the safety of LK1 powder. Following Organisation for Economic Co-operation and Development (OECD) guidelines, a single-dose oral toxicity test in Sprague Dawley rats was performed. Genotoxicity was assessed using a bacterial reverse mutation test with Salmonella typhimurium (strains TA98, TA100, TA1535, and TA1537) and Escherichia coli WP2 uvrA, an in vitro mammalian chromosome aberration test using Chinese hamster lung cells, and an in vivo mammalian erythrocyte micronucleus test using Hsd:ICR (CD-1) SPF mouse bone marrow. After LK1 administration (2,500 mg/kg), there were no LK1-related body weight changes or necropsy findings. The reverse mutation test showed no increased reverse mutation upon exposure to 5,000 ㎍/plate of the LK1 powder, the maximum tested amount. The chromosome aberration test and micronucleus assay demonstrated no chromosomal abnormalities and genotoxicity, respectively, in the presence of the LK1 powder. The absence of physiological findings and genetic abnormalities suggests that LK1 powder is appropriate as a candidate biomass to be used as a safe food ingredient.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.4
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• pp.118-127
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• 2005

The best way to treat livestock manure is a recycling the manure to arable land as an organic fertilizer. In this study, fermented cow manure compost and pig manure compost were used as a raw materials for pelletizing. The changes of physicochemical properties of each composts and pellets were investigated. The aim of this research was to improve availability of livestock manure compost. In pelletizing process of fermented livestock manure compost, the optimal water content to make pellet was around 40%. When clay was mixed by volume more than 15% as a bonding agent, the condition of pelletizing process was beginning to improve. On a dry matter basis, the contents of N, P and K of fermented pig manure compost were 2.05%, 1.89% and 1.31%, respectively. After pelletizing, the contents of compost pelleted with the pig manure compost were 1.96% 1.73% and 0.89%, respectively. The same parameters of cow manure compost were 2.52%, 1.01% and 2.98%, respectively. After processing, the contents of compost pelleted with the cow manure compost were 2.45%, 1.10% and 2.93%, respectively. After pelletizing, there were little change in the content of heavy metals such as Pb, Cd, As and Hg. When pelleted compost dried naturally was submerged in water, it was completely dissolved in 30 minutes. On the other hand, Pelleted compost dried with the mechanical convection oven set $70^{\circ}C$ for 24 hours was completely dissolved in 960 minutes. The volume and weight of pelleted compost were decreased with time. After 30 days of storing, the weight of pelleted compost was decreased by 15% compared with its original weight. The volume of it was decreased by 17~25% in the same time.

• Korean Journal of Environmental Agriculture
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• v.19 no.1
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• pp.32-37
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• 2000

Because the household garbage had high water contents, it is difficult to compost it without an additive. Therefore, this study was performed to investigate possibility of using the waste newspapers as a humidity conditioner for the household garbage composting. The maximum temperature was $66.0^{\circ}C$ in spring, $69.2^{\circ}C$ in summer, $60.9^{\circ}C$ in fall and $56.0^{\circ}C$ in winter for composting periods. The seasonal pH value reached around 8.5 after 1 week and then repeated fluctuation at the narrow range in spring and fall, while it was stabilized at the range of $8{\sim}9$ after increasing to 8.5 after 1 week in winter. The water content was reduced little in winter, while decreased significantly in the other seasons. The water content after 8 weeks was 22.2% in spring, 47.6% in summer, 25.5% in fall and 72.5% in winter. The mass was reduced rapidly during the first week of each season, but it did not show much decrease. The volume reduced after 8 weeks to 59%, 32%, 27%, and 34% in spring, summer, fall and winter respectively. Organic matter content decreased over the four seasons. Nitrogen contents were in the range of 0.7% to 2.2% during the four seasons. The contents of inorganic compounds based on dry matyter were in the range of $0.94{\sim}2.59%\;P_2O_5$, $1.23{\sim}1.87%\;CaO$, $0.37{\sim}0.46%\;MgO$, $0.55{\sim}1.98%\;K_2O$. Concentration of heavy metals(Hg, Cd, Pb, Cu, Cr, Zn, As) based on dry matter were less than the limiting value of the by-product compost.

• Economic and Environmental Geology
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• v.35 no.3
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• pp.241-255
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• 2002

The purpose of this study is to investigate environmental geochemical characteristics for the acid mine drainage and stream sediments in the abandoned Honam coal mine area. For the chemical analysis, stream winter samples were collected at 54 sites and for the mineralogical and chemical analysis, stream sediments samples were collected at 34 sites. Physical and chemical characteristics of stream water were measured at the site and chemical compositions were analyzed by ICP-AES, ICP-MS and IC. Mineralogical characteristics of stream sediments samples were determined using XRD, SEM and EDS. In physical and chemical properties, stream water shows thats pH 2.85~8.12, Eh -62~215 mV, EC 0.205~146 ms/m, ER 0.234~255 {$\Omega}{\cdot}$m, DO 0.03~1068 mg/L and TDS 10.96~1420mg/L. In chemical compositions, we obtain that K 0.118~3.184 mg/L, Mg 2.1~114.48 mg/L, Ca 2.59~l25.02 mg/L, Al 0.01~44.72 mg/L, Fe 0.108~89.49 mg/L and Na 5.45~125.41 mg/L. Stream sediments are commonly composed of quartz, illite and goethite in the result of x-ray diffraction. After heat treatment at 98$0^{\circ}C$, the hematite peaks are distinctly shown. In consideration of heavy metals (include Fe) for steam sediments, Fe ranges 22575~34713 ppm, Zn 41.66~970.3 ppm, Cd 0.52~52.07 ppm, Cu 1.25~198.5 ppm and Pb 0.43~77.35 ppm.