• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.8
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• pp.338-343
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• 2017

In this study, blast furnace slag powder was used in concrete to help reduce carbon dioxide emissions and to recycle industrial waste. Blast furnace slag powder is a byproduct of smelting pig iron and is obtained by rapidly cooling molten high-temperature blast furnace slag. The powder has been used as an admixture for cement and concrete because of its high reactivity. Using fine blast furnace slag powders in concrete can reduce hydration heat, suppress temperature increases, improve long-term strength, improve durability by increasing watertightness, and inhibit corrosion of reinforcing bars by limiting chloride ion penetration. However, it has not been used much due to its low compressive strength at an early age. Therefore, this study evaluates the effects of steam curing for increasing the initial strength development of concrete made using slag powder. The relationship between compressive strength, SEM observations, and XRD measurements was also investigated. The concrete made with 30% powder showed the best performance. The steam curing seems to affect the compressive strength by destroying the coating on the powder and by producing hydrates such as ettringite and Calcium-Silicate-Hydrate gel.

• Journal of the Korean Society of Safety
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• v.20 no.3 s.71
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• pp.188-196
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• 2005

Accident reports from 1991 to 2000 of a steel company were used to analyze which factors induce industrial accidents. The subjects were 8,311 blue-collar workers, who sustained 114 occupational injuries and work on a continuous full-day 3-team 3-shift system of backward rotation(mornings to afternoons to nights). With respect to marital status, the occupational injury rate(OIR) on the married workers was significantly higher compared to unmarried workers. With respect to no, the OIR of those in their early 20s was significantly higher when compared to other age groups. The OIR of highly educated workers showed a reduction when compared with lower educated workers. The OIR of shift workers were significantly higher compared with the daytime workers. The OIR of type of work decreased across the steel manufacturing process, rolling process, machine maintenance section forwarding products section to the field management section. With respect to the block of shift work(morning, afternoon, and night shifts) by the type of work, the OIR of the night shift was higher than those of the morning shift in the steel manufacturing process or forwarding products section. The OIR of the machine maintenance section was slightly higher in the morning shift than those of the night shift. The OIR of the time of day of the shift workers reached a peak between 09:00 and 11:00. The OIR of a slight injury to shift workers decreased across the night, afternoon, to morning shifts whereas the OIR of a serious injury tended to decrease across the night, morning, to afternoon shift. The body parts most commonly injured were the arm and the crus.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.1
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• pp.9-15
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• 2023

The cement is a typical CO₂ emission industry. Manufacturing process improvements and increased use of alternative materials are needed to reduce energy consumption and CO₂ emissions. This study confirmed the basic characteristics of cement hydration by sintering CAF at low temperature as a CO₂ adsorbent material. For the hydration product of the synthetic CAF, crystal phase analysis, porosity, and structural images were confirmed, and the compressive strength was measured. The replacement rate of SCAF was 10, 20, and 100 %, and the compressive strength tended to decrease as the replacement rate increased. In addition, when the SCAF substitution rate is 100 %, the hydration products of the early age are calcium aluminum oxide hydrate (Ca₃Al₂O₆ x H₂O) and calcium iron hydroxide (Ca₃Fe(OH)₁₂), and at substitution rates of 10 and 20 %, CAF compounds other than general cement hydrates brownmillerite was observed. As for the porosity, the pore size increased and the porosity increased with the increase of the replacement ratio. As a result of this study, CAF manufactured by low-temperature sintering seems to be difficult to use alone and general curing for utilization as a CO₂ adsorbing material.

• BMB Reports
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• v.40 no.5
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• pp.757-764
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• 2007

Marbling of cattle meat is dependent on the coordinated expression of multiple genes. Cattle dramatically increase their intramuscular fat content in the longissimus dorsi muscle between 12 and 27 months of age. We used the annealing control primer (ACP)-differential display RT-PCR method to identify differentially expressed genes (DEGs) that may participate in the development of intramuscular fat between early (12 months old) and late fattening stages (27 months old). Using 20 arbitrary ACP primers, we identified and sequenced 14 DEGs. BLAST searches revealed that expression of the MDH, PI4-K, ferritin, ICER, NID-2, WDNMI, telethonin, filamin, and desmin (DES) genes increased while that of GAPD, COP VII, ACTA1, CamK II, and nebulin decreased during the late fattening stage. The results of functional categorization using the Gene Ontology database for 14 known genes indicated that MDH, GAPD, and COP VII are involved in metabolic pathways such as glycolysis and the TCA cycle, whereas telethonin, filamin, nebulin, desmin, and ACTA1 contribute to the muscle contractile apparatus, and PI4-K, CamK II, and ICER have roles in signal transduction pathways regulated by growth factor or hormones. The final three genes, NID-2, WDNMI, and ferritin, are involved in iron transport and extracellular protein inhibition. The expression patterns were confirmed for seven genes (MDH, PI4-K, ferritin, ICER, nebulin, WDNMI, and telethonin) using real-time PCR. We found that the novel transcription repressor ICER gene was highly expressed in the late fattening stage and during bovine preadipocyte differentiation. This information may be helpful in selecting candidate genes that participate in intramuscular fat development in cattle.

• Clinical and Experimental Pediatrics
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• v.48 no.3
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• pp.284-291
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• 2005

Purpose : Flow cytometric automated reticulocyte analysis is a superior method to manual reticulocyte counting, with respect to precision and sensitivity. Furthermore, flow cytometric analysis is able to measure immature reticulocyte fraction(IRF) and reticulocyte cellular indices(RCI : cell hemoglobin content : CHr, mean cell volume : MCVr, cell hemoglobin concentration mean : CHCMr, distribytion width : RDWr, HDWr, CHDWr). In this study, we investigated the mean values and clinical significances of IRF and RCI in healthy children and pediatric anemia patients. Methods : IRF and RCI were measured with an automated blood cell analyzer, ADVIA 120(Bayer, USA) using oxazine 750 dye, in 57 healthy children and 61 children with anemia. The anemia group consisted of 27 iron deficiency anemia(IDA) patients and 34 patients with anemia associated with acute infection(AAI). We compared the mean values of IRF and RCI in the control group classified according to age, between anemia groups and the control group, and between the IDA group and the AAI group. Results : For the normal control group, the mean values of IRF, CHr, MCVr and HDWr were higher in neonates when compared to older children. The mean values of IRF and RDWr were significantly higher, and the mean values of CHr and CHCMr were significantly lower in the IDA group when compared to the control group. The mean value of IRF was significantly higher, and the mean value of CHDWr was significantly lower in the AAI group when compared to the control group. The mean values of IRF, CHr and CHCMr were significantly lower in the IDA group when compared to the AAI group. Conclusion : We could determine the normal mean values of IRF and RCI in healthy children classified according to age for understanding of hematopoietic response differences according to age. The evaluation of IRF and RCI by automated reticulocyte analyzer seemed to be accurate and clinically useful for the early diagnosis of anemia and the differentiation of IDA from AAI.

• Economic and Environmental Geology
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• v.28 no.3
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• pp.185-197
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• 1995

Tungsten skarns in the Chungju mine which consists mainly of strata-bound type iron ore deposits are found in the vicinity of the contact between the age-unknown Kyemeongsan Formation and granitic rock intrusions of Mesozoic age($134{\pm}2Ma$). Tungsten skarns were formed extensively from alumina and silica-rich schistose rocks by the introduction of calcium and iron from hydrothermal solution. The skarns comprise a metasomatic column and are subdivided into four facies; garnet facies, wollastonite facies, epidote facies and chlorite facies. The skarn process in time-evolutional trend can be divided broadly into the four facies in terms of the paragenetic sequence of calc-silicates and their chemical composition. Skarn and ore minerals were formed in the following sequence; (1) garnet facies, adjacent to biotite granite, containing mainly garnet(>Ad96) and magnetite, (2) wollastonite facies containing mainly wollastonite and garnet(Ad95~60), (3) epidote facies, containing mainly epidote(Ps35~31), quartz, andradite-grossular(Ad63~50), and scheelite, (4) chlorite facies, adjacent to and replacing schist, containing mainly chrolite, muscovite, quartz, calcite, epidote(Ps31~25), hematite and sulfides. The mineral assemblage and mineral compositions. suggest that the chemical potentials of Ca and Fe increased toward the granitic rock, and the component Al, Mg, K, and Si decreased from the host rock to granitic rock. The homogenization temperature and salinity of fluid inclusion in scheelite, quartz and epidote of epidote facies skarn is $300-400^{\circ}C$ and 3-8wt.% eqiv. NaCl, respectively. ${\delta}^{34}S$ values of pyrite and galena associated with chlorite facies skarn is $9.13{\sim}9.51%_{\circ}$ and $5.85{\sim}5.96%_{\circ}$, respectively. The temperature obtained from isotopic com· position of coexisting pyrite-galena is $283{\pm}20^{\circ}C$. Mineral assemblages and fluid inclusion data indicate that skarn formed at low $X_{CO_2}$, approximately 0.01. Temperature of the skarn mineralization are estimated to be in the range of $400^{\circ}C$ to $260^{\circ}C$ and pressure to be 0.5 kbar. The oxygen fugacity($fo_2$) of the skarn mineralization decreased with time. The early skarn facies would have formed at log $fo_2$ values of about -25 to -27, and late skarn facies would have formed at log $fo_2$ values of -28 to -30. The estimated physicochemical condition during skarn formation suggests that the principal causes of scheelite mineralization are reduction of the ore·forming fluid and a decrease in temperature.

• Journal of Conservation Science
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• v.35 no.5
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• pp.508-517
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• 2019

This study analyzed on alloys and by-product samples produced through the reproduction experiment of bronze mirror with geometric designs. The alloy ratio used in the first and second reproduction experiments was based on the analysis results of bronze mirror with geometric designs(Cu 61.68%, Sn 32.25%, Pb 5.46%) which is the national treasure No. 141. As a result of portable X-ray fluorescence analysis on the raw materials used in the reproduction experiment, the contents of copper raw materials were 98.85 wt% for Cu, tin raw materials were 99.03 wt% for Sn, and lead raw materials were 70.19 wt% for Pb, and 21.81 wt% for Sn. Sn and Pb were added 5 wt% more considering the evaporation amount of tin and lead during alloy melting. The result produced by the first reproduction experiment were 58.75 wt% for Cu, 36.87 wt% for Sn, 4.39 wt% for Pb, and the other result produced by the second reproduction experiment were 58.66 wt% for Cu, 35.89 wt% for Sn, and 5.50 wt% for Pb. The composition of the components was about 3.00 wt% in Cu and Sn respectively, and the microstructure was similar to the previous studies because the δ phase was observed mainly. The results of this study will be used as basic data for the materialistic characteristics of ancient bronze mirror in the future.

• Journal of the Daesoon Academy of Sciences
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• v.17
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• pp.113-134
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• 2004

According to Hans Kippenberg, the foundation of an academic study of religions coincided with the beginnings of modernization. Since the second half of the nineteenth century most European countries were involved in a process of rapid social change. The repercussions that this had for daily life were momentous. Instead of working for their traditional needs, people now had to produce goods for a market. Old customs ceded to private contracts and political laws. The superior knowledge of science replaced the inherited worldview. This deep changed severed societies from their ties to the past. Many educated people in Europe believed in an imminent end of all religions. Had not the scientific progress superseded the religious worldview? Historians had to come to terms with that expectation when they directed their attention to historical religions. Friedrich Max Muller introduced a new science, so-called Religionswissenschaft through the study of the ancient Vedic sources. He thought that genuine religion was a taste for, and sense of, the infinite. From his point of view, the Indian sources confirm that nature is more than mechanical laws. Thus his interpretation sought to contradict the materialist ideology of his day. Edward Burnett Tylor described religions as a kind of natural philosophy. His notion of 'soul' functioned to explain natural events. This legacy of the past cannot be missed even in modern society. Only the concept of the soul may preserve human dignity in an age of materialism. Gerardus van der Leeuw, also tried to perform the same function of the cultural critique for the renewal of the religious imagination in modern, rationalized Europe imprisoned in the iron-cage. In this respect, we could think that the interpretations of the history of the History of Religions in the light of the intellectual history are very suggestive for the korean student of religion. It helps them to describe the early history of the study of religion in Korea. For example, Yi Neung Wha(李能和) is regarded as 'a father of korean religious studies, but no one could present a proper answer for the question of why and through which connection of his intellectual milieu he was interested in the religious history and the study of religion. We would discover its signification in his confrontation of the prevailing social thought, such as social evolutionism.

• The Korean Journal of Food And Nutrition
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• v.11 no.1
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• pp.87-98
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• 1998

This study was conducted to investigate Osteoporosis on the effect of dietary factors and past young age period's dairy products consumption on BMD in 170 postmenopausal Korean women without diagnosed disease. Bone mineral density(BMD) of lumbar spine was investigated by dual energy X-ray absorptiometry. Dietary assesment of the subjects were measured by Cognitive Food Frequency Recall method. The measurements of group average were 57.9kg of body weight, 36.73 of BMI(Body Mass Index), 2103.3㎉ of energy, 638.7mg of dietary calcium, 70.3g of protein, and 10.58mg of iron. Nutrient intake levels were similar to or more than the level of Korean Recommended Dietary Allowances. Bone Mineral Density(BMD) of Lumbar spine(L2-L4) of group average was 0.912g/$\textrm{cm}^2$, and under 50 yr's 1,02g/$\textrm{cm}^2$, 50~54 yr's 0.92g/$\textrm{cm}^2$, 55~59 yr's 0.85g/$\textrm{cm}^2$, over 60 yr's 0.85g/$\textrm{cm}^2$, had been getting low degree on aging. BMD of the Lumbar spine was positively correlated with calorie, body weight, dietary calcium, protein, phosphorus and serum albumin. Past dairy products consumption experiment was highly significant on BMD in teenage period(R square = 26, p-value 0.0031). Particularly in over 60 yr group, the correlations between BMD and past dairy products consumption in teenage period had shown highly significance(r=0.48, p<0.02). 55~59 yr age group had also positive correlation(R squae = 0.29, p<0.05). This results confirm that the most effective way of preventing osteoporosis and the fractures is to maximize peak bone mass in early life and to minimize bone loss through the balanced intake of Ca and other nutrients and regular physical activity.

• Korean Journal of Heritage: History & Science
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• v.54 no.2
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• pp.4-21
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• 2021

A stone mold from the Sabi period of Baekje was excavated at the western tombs in Neungsan-ri, Buyeo where there was a recent excavation survey (2016). It was believed and reported that such stone molds were used for copper needles during the early Iron Age; however, a close re-examination of the form revealed that they were used for bifid ornamental hairpins. Given its casting form, the stone mold of Neungsan-ri is estimated to have been used to make bifid ornamental hairpins in a ∩ shape, narrowing down toward the tip. It is considered an artifact of the Goryeo dynasty. The stone used to make the bifid ornamental hairpin mold of Neungsan-ri was chlorite-schist, the principal minerals of which include chlorite, amphibole, and talc. Similar rocks are in nearby Buyeo (Oesan-myeon), Cheongyang, Gongju, and Yesan. They are mainly found between Jiseon-ri, Oesan-myeon, Buyeo, Sucheol-ri, Yesane-up, and Yesan. Nearly 70 bifid ornamental hairpins from the Goryeo dynasty were excavated at Neungsan-ri, Buyeo and the surrounding areas. Among them, the bronze ones excavated from the tombs of Songguk-ri, Buyeo are estimated to have been made using this mold as they closely resemble the Neungsan-ri mold. Stone was likely the preferred material for molds to make bronze artifacts as it was easy to sink a die. Regarding the bifid ornamental hairpin cast excavated in Neungsan-ri, they obtained stones in nearby areas 20~50km from their location, made bronze artifacts, and distributed them to nearby sites during the Goryeo dynasty. These artifacts suggest that the casting technology of using a stone mold was still employed then.