• Journal of the Korea Institute of Building Construction
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• v.23 no.5
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• pp.583-593
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• 2023

For a holistic and precise assessment of safety benchmarks within a construction venture, it's paramount to delineate between the intrinsic features of the construction and its real-time, on-site performance metrics. In this study, we delved into genuine accident instances to discern the interplay between these construction attributes and on-ground performance determinants in relation to safety mishaps, employing the binomial logit analytical framework. Our scrutiny underscored that construction expenditure profoundly modulates the likelihood of fatal occurrences. Notably, variables pertinent to on-site safety protocols wielded considerable influence over both fatal mishaps and accidents implicating multiple personnel. These revelations intimate that while ascertaining the safety quotient of a construction initiative, a mere classification and recalibration based on fiscal dimensions can elucidate much. Yet, a comprehensive safety appraisal necessitates transcending quantitative indices, such as frequency of mishaps or casualty rates, to encapsulate the multifaceted interventions and strategies adopted at the construction locale.

• Advances in environmental research
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• v.6 no.3
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• pp.159-171
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• 2017

A successful oil well drilling depends largely on a good mud Program. During drilling, mud provides sufficient hydrostatic pressure, removes drill cuttings and cools drill bits. Mud additives are always required to provide sufficient hydrostatic pressure to ensure borehole stability. Barium Sulphate ($BaSO_4$) also known as barite is the prevalent weighting material but there is needed to develop local materials to augment the use of Barite. The present search is concerned on the early Carboniferous succession exposed in Um Bogma Formation, west central Sinai, Egypt as a new weighting agent in drilling fluids. The increases in the cost of drilling fluids and a shortage of using barite have introduced the locale dolomite as alternative weighting materials. The rheological properties of mud drilling samples weighted by local dolomite samples are being examined and investigated to know its potential to be used as a weighting material in drilling mud. Two mud samples were prepared which comprised of fresh water, caustic soda, bentonite and the weighting material. The weighting materials are added to achieve the required density. The first sample: Water-based mud with commercial barite of density between 10.00 lb/gm and 18.00 lb/gm. The second sample: Water-based mud with dolomite of density between 10.00 lb/gm and 18.00 lb/gm. These samples were analyzed and the density, rheological properties, aging of barite and dolomite and solid contents were investigated. At 10.00 lb/gm, the yield point of dolomite was $20.00lb/100ft^2$ and barite $22.00lb/100ft^2$ while the 10 second gel strength of dolomite was $30.00lb/100ft^2$ and $22.00lb/100ft^2$ for barite. Similarly, little difference was observed in plastic and apparent viscosities. At 10.00 lb/gm, the plastic and apparent viscosities of dolomite were 8.00 cp and 20.00 cp while barite was 8.00 cp and 24.00 cp. The result show that dolomite mud sample gave a little higher yield point and gel strength than barite mud sample. Therefore, dolomite has the potential to be used as weighting material in drilling mud in place of barite thereby enhancing the local content initiative of the government. When dolomite is sourced locally and used it will reduce overall mud and drilling costs.

• The Korean Journal of Mycology
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• v.46 no.1
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• pp.34-42
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• 2018

Tricholoma matsutake (Pine mushroom) is expensive, and its artificial cultivation has been tried in several countries. Until date, the only successful cultivation of artificial pine mushroom in pine forests uses matsutake-infected pine trees. The National Institute of Forest Science in Korea has been restudying this method since 2000. Success in fruit production and reproduction was achieved in 2010 and 2017, respectively, in the same locale. The successes proved that pine mushrooms could be cultivated artificially in the field using matsutake-infected pine trees. The fruiting of pine mushroom in October 2010 occurred 6 years, 6 months after the transplantation of matsutake-infected pine trees. Five pine mushrooms reoccurred in September 2017, 13 years, 5 months and 15 years, 5 months after the transplantation of the respective matsutake-infected pine trees. The distance between the matsutake-infected pine tree and the pine mushrooms was 12 cm at 6.6 years, 90~115 cm at 13.5 years, and 95 cm at 15.5 years. Fruiting bodies occurred 13~16 days after the underground temperature declined to below $19^{\circ}C$. In conclusion, the use of matsutake-infected pine trees remains the only way to artificially cultivate pine mushrooms. More knowledge of the environmental factors affecting matsutake fruiting would be beneficial.

• Journal of The Korean Association For Science Education
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• v.27 no.9
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• pp.818-831
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• 2007

Recognizing the importance of abductive inquiry in Earth science, some theoretical approaches that deploy abduction have been researched. And, it is necessary that the abductive inquiry in a geological field excursion as a vivid locale of Earth science inquiry should be researched. We developed a geological field trip based on the abductive learning model, and investigated students' abductive inference, thinking strategies used in those inferences, and the impact of a teacher's pedagogical intervention on students' abductive inference. Results showed that students, during the field excursion, could accomplish abductive inference about rock identification, process of different rock generation, joints generation in metamorpa?ic rocks, and terrains at the field trip area. They also used various thinking strategies in finding appropriate rules to construe the facts observed at outcrops. This means that it is significant for the enhancement of abductive reasoning skills that students experience such inquiries as scientists do. In addition, a teacher's pedagogical interventions didn't ensure the content of students' inference while they helped students perform abductive reasoning and guided their use of specific thinking strategies. Students had found reasoning rules to explain the 01: served facts from their wrong prior knowledge. Therefore, during a geological field excursion, teachers need to provide students with proper background knowledge and information in order that students can reason rues for persuasive abductive inference, and construe the geological features of the field trip area by the establishment of appropriate hypotheses.

• Korean Journal of Environmental Biology
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• v.36 no.1
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• pp.73-81
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• 2018

This study was conducted to understand the current status of the translocated species using a precede study and a model to evaluate the potential invasiveness that could adversely affect the aquatic ecosystem in the Gangneungnamdae Stream. A total of 12 translocated species were investigated and identified from 9 sites in a precede study, and steadily increased since 1982. For the study, which utilized research based on the total FISK (Fish Invasivenss Screening Kit) scores, all of the non-native fishes in Gangneungnamdae Stream were classified into two groups: namely as a high and a medium risk of becoming invasive. It was determined that there were two species (Zacco platypus and Pseudorasbora parva) that were determined to have posed the highest risk. The study determined that the mean scores were shown to have ranged from $3.06({\pm}0.16)-3.42({\pm}0.13)$. Consequently, the habitat analysis showed that the determined QHEI (Qualitative Habitat Evaluation Index) values in the stream averaged 146 (88-171), indicating that an optimal habitat condition did exist in that locale. It can be inferred that compared to land use in the surrounding watersheds, the QHEI values and frequency of translocated species showed the lower the altitude of stream, the QHEI values were decreased and in case of land use pattern, a noted decreased forest and grassland area, and gradually increased urbanized area was seen to exist in the region. The correlation between the fish assemblage, QHEI, land use pattern of surrounding watershed and number of translocated species was identified and analyzed when the stream altitude decreased, and the number of species was increased (r= - 0.782, p=0.0127), the number of species was decreased (r= - 0.737, p=0.0234), and finally when the QHEI values were decreased, it was noted that the urbanized area was increased (r=0.292, p=0.446). In the case of the number of translocated species, when the number of translocated species was increased, the associated urbanized area was increased.

• Journal of the Economic Geographical Society of Korea
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• v.9 no.1
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• pp.23-38
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• 2006

This study attempts to investigate the spatial characteristics of cultural economies of Bukchon in Seoul, where abundant cultural assets exist. This area has been the administrative-political core locale since 14C, therefore, a lot of traditional- and contemporary-cultural facilities are remains, This area possessed unique place characteristics by coexisting traditional and modern cultures, and thus attracted to culture demanders. Recently many economic activities have increased in this area, and most of them are related with the cultural elements of the region, In particular creative retail shops, which produce goods by flexible-specialized production system, have been agglomerated in this area, The goods are designed, produced, and sold at the shop place. Most of them are uniquely designed hand made products, and produced a few amount. The economic value of these products related with the cultural environment of Bukchon. These creative shops emerged at the front of Samcheongdong street in the beginning, and then have diffused into the inside of Samcheongdong street and Hwagae street. The shops have very unique exteriors related with traditional houses in this area, and located on roadsides where are not many passerby. Most owners of the retail stores are highly educated and studied design, and produce goods by themselves at the shops. The reason that they opened their shops in Bukchon is directly related with the unique cultural environment of this area. They hope that more unique and artistic stores join this area so that developed this area as culture and fashion combined area.