• Proceedings of the KSR Conference
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• 2006.11b
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• pp.345-349
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• 2006

There has been an increasing demand for the mitigation of noise and vibration caused by KTX. One of considered noise reduction methods which is to enlarge mud-flap in gangway was selected and the replacement of all KTX mud-flaps by improved mud-flaps was completed recently. To investigate the noise characteristics of KTX with improved mud-flap, the measurement was performed. Based on the measurement results, the assessment of noise level, noise characteristics by speed and pure tone analysis for various track conditions was executed. It is shown that the use of improved mud-flap is effective to reduce the interior noise of KTX.

• Journal of the Korean Geophysical Society
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• v.5 no.1
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• pp.51-62
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• 2002

Investigation of underwater sedimentary layers has been carried out with GPR(Ground Penetration Radar) survey. FPR survey has been proved to be very satisfactory since the target area has shallow water depth of about 2.5 m, is a lake with no water flow, and the thickness of mud layer, which is a main survey target, is relatively thin. The results clearly showed the underwater sedimentary layers, which includes mud, sand, gravel and basement layer. Specially, the distribution and total amount of mud layers from the survey results can be used as a basic data for the dredging of mud layer in the area.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.70-71
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• 2021

An increasing amount of red mud (RM) is being generated globally with the growth in alumi-num production. To avoid the RM becoming a pollutant, methods for effectively recycling RM at a low cost are being investigated. This study proposes a method for recycling RM as a construc-tion material. The cement paste with neutralized liquefied red mud had higher compressive strength than that of plain cement paste and cement paste with liquefied red mud without neutralization at 1 d of aging; this indicates that nitric acid neu-tralization increases the early-age strength.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.6
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• pp.656-665
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• 2019

Environmental monitoring was conducted to identify the characteristics and patterns of sedimentary environments of tidal flats in 12 areas on the west coast of Korea. The habitat of the mud shrimp Upogebia major contained higher organic and mud contents compared to the habitat of the manila clam Ruditapes philippinarum. In particular, the mud content increased from 84.38% to 89.18% in the Seongam-4 area, where the mud shrimp and manila clam coexist, and the mean grain size exhibited a finer particle size, from 5.48 Φ to 5.80 Φ. In the mud shrimp habitat, the sediment mud content was > 60% and the mean grain size was > 5 Φ. Additionally, the mud shrimp only inhabited open coast tidal flat areas. The management of shellfish aquaculture farms by physical methods should be continued based on comparison of the sedimentary environments in the Boryeong and Seongam areas in response to the damage to the mud shrimp habitat.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.2
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• pp.124-137
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• 2010

This study was started with the objective of restoring abandoned embanked farms, which are recently increasing, to mud flat by putting in least amount of energy in the aspect of environmental restoration. For the direction and establishment of the proposal for the restoration of mud flat using embanked farms, a case of Maipo Wetland in Hongkong was analyzed, and a proposal was prepared considering the condition of mud flat in Gochang. The restoration of mud flat in Gochang is intended to create various wetland ecological spaces as well as to provide opportunities for experience, education, recreation, and tourism. Effort was made to development an environment closest to the local ecological environment considering the shape and topographical condition of existing abandoned farms. For construction of the habitat, a target species was chosen and the plan for selection, planting, and management of species of trees suitable for the target species was established. In addition, the water level will be controlled by water gates to conform to the resting, spawning, breeding, and migration period considering the behavioral pattern of waders, the target species. The research on the restoration of mud flat in Korea is in incipient stage and this study provided an opportunity to review the possibility of restoration of abandoned embanked farms to mud flat. For the success of mud flat restoration from a long-term perspective, development of acclimating design infrastructure, technology improvement for mud flat restoration, and basis of partnership for the maintenance should be prepared in a systematical way.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.2
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• pp.26-33
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• 2016

The alkali-slag-red mud(ASRC) cement belongs to clinker free cementitious material, which is made from alkali activator, blast-furnace slag(BFS) and red mud in designed proportion. This study is to investigate strength and pore characteristics of alkali-activated slag cement(NC), clinker free cementitious material, and ordinary portland cement(C) mortars using polymer according to red mud content. The results showed that the hardened alkali-activated slag-red mud cement paste was mostly consisted of C-S-H gel, being very fine in size and extremely irregular in its shape. So the hardened ASRC cement paste has lower total porosity, less portion of larger pore and more portion of smaller pore, as compared with those of hardened portland cement paste, and has higher strength within containing 10 wt.(%) of alkali-activated slag cement(NC) substituted by red mud.

• Journal of the Korean GEO-environmental Society
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• v.23 no.4
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• pp.21-27
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• 2022

Recently, numerous studies are being performed to examine alkali-activated cement which uses industrial by-products, such as GGBS and fly ash, as well as alkali activators. Alkali-activated cement is a type of binder that exerts the same strength as cement without using cement by mixing industrial by-products with alkali activators. Alkali activators, which are used mainly for carbon-reducing technologies and alkali activation, are expensive and difficult to apply in the field due to risks related to strong alkalinity. Therefore, this study intends to explore methods to use red mud as a substitute for an alkali activator. To that end, this study has evaluated engineering properties, such as flow and strength, of CLSM that uses red mud and paper sludge ash as binders and its possibility to cause soil pollution. This study also aims to present the appropriate mixing ratios of red mud and paper sludge ash to produce CLSM.

• The Korea Journal of Herbology
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• v.23 no.2
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• pp.81-85
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• 2008

Objectives : The aim of this study is to collect data for toxicity and safety of Mud chrysanthemum indicum. Methods : In this study, we investigated the acute toxicity for buthanol-extracted Mud schrysanthemum indicum, 25 male and 25 female mice were observed for 14days after one day oral administration of Mud chrysanthemum indicum at the respective doses of 0(control group), 1024, 1280, 1600 and 2000mg/kg. Results : We observed survival rates, general toxicity, change of body weight and autopsy. No abnormality was found for all cases. Conclusions : The data confirmed that Mud chrysanthemum indicum is free from, the toxicity and safety problems. Compared with the control group, we could not find any toxic alteration in all treated groups (1024, 1280, 1600 and 2000mg/kg), In conclusion, LD50 of Mud chrysanthemum indicum was over 2000 mg/kg and it is very safe to mice.

• Journal of the Korean housing association
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• v.22 no.6
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• pp.61-69
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• 2011

Korea's traditional house type, the Hanok, has been the essence of Korean domestic culture for hundreds of years. However, Hanok, have begun to disappear as result of urbanization. Because mud walls are crude and weak in water walls are also easily broken by impact. There are further problems in that construction cost is expensive and takes more time than modern house construction, and that the maintenance of Hanok is more difficult than people sometimes predict. Despite much interest in Hanok construction, there is a lack of in younger generation. Thus seeking new ways of maintaining Korea's traditional housing culture and extending Korean traditional houses is important. This study proposes directions for creating new residential environments for the future generation of Korea. A Dry-wall alternative to the Korean traditional mud wall is particularly needed. Dry-walling, made by sustainable materials such as mud board and wood, can strengthen the advantages and make up for the weaknesses of the Korea traditional mud wall. In this study, both wall types underwent various evaluations in terms of their performance in insulation testing, freezing and thawing testing, impacting testing and weight measuring (the size of material in this experiment was $69cm{\times}105cm$). On all of these tests, findings revealed that the dry-wall alternative performed better than traditional mud wall.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.3
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• pp.276-283
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• 2016

Red mud is an inorganic by-product produced from the mineral processing of alumina from Bauxite ores. the development of alkali-activated slag-red mud cement can be a representative study aimed at recycling the strong alkali of the red mud as a construction material. This study is to investigate the optimum water content, compressive strength, moisture absorption coefficient and efflorescence of alkali-activated slag-red mud soil pavement according to the recycling fine aggregate content. The results showed that the optimum water content, moisture absorption coefficient and efflorescence area of alkali-activated slag-red mud soil pavement increased but the compressive strength of that decreased as the recycled fine aggregate content increased.