• Title/Summary/Keyword: water-friendly

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Characteristics Evaluation of Lathe Scrap for Manufacturing Fiber Reinforced Cementitious Composites (섬유보강 시멘트 복합체 제조를 위한 선반 스크랩의 특성 평가)

  • Bae, Suho;Jeon, Juntai;Kwon, Soonoh;Lee, Hyunjin;Kim, Sungwook
    • Journal of the Society of Disaster Information
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    • v.10 no.3
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    • pp.432-441
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    • 2014
  • The purpose of this research is to investigate characteristics of lathe scrap for manufacturing fiber reinforced cementitious composites(FRCCs) to use lathe scrap as a alternative materials of steel fiber. It should be noted that the use of the lathe scrap for making FRCCs raised friendly environmental effect as well as economy because the lathe scrap was a by-product of steel manufactures. For this purpose, various steel scraps were collected from processing plants of metal and then their physical properties were evaluated. Also, steel scraps were classified and analyzed according to the KS D 2101 and then of these scraps, lathe scrap as a alternative materials of steel fiber was suggested. In addition, FRCCs containing lathe scraps were made according to their total volume fractions of 0.0, 0.5, 1.0, 1.5, and 2.0% for water-binder ratios of 30%, 40%, respectively, and then characteristics, such as the workability, compressive strength, and flexural strength of those were evaluated. It was observed from the test result that the compressive strengths at 7 and 28 days of FRCCs containing lathe scrap were slightly small but the flexural strengths at 28 days of those increased by 10% compared with plain concrete.

A Study on Mechanical Characteristics of Fiber Modified Emulsified Asphalt Mixture as Environmentally-Friend Paving Material (섬유보강 친환경 상온아스팔트 혼합물의 역학적 특성에 관한 연구)

  • Rhee Suk-Keun;Park Kyung-Won
    • International Journal of Highway Engineering
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    • v.8 no.2 s.28
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    • pp.23-30
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    • 2006
  • Emulsified Asphalt Mixture(EAM) is more environmentally-friendly and cost-effective than typical Hot Mix Asphalt (HMA) because EAM does not produce carcinogenic substances, e.g., naphtha, kerosene, during the both of manufacturing and roadway construction process. Also, it does not require heating the aggregates and asphalt binder. However, EAM has some disadvantages. Generally EAM has a less load bearing capacity and more moisture susceptibility than conventional HMA. The study evaluated a Fiber modified EAM (FEAM) to increase load bearing capacity and to decrease moisture susceptibility of EAM. Modified Marshall mix design was developed to find Optimum Emulsion Contents (OEC), Optimum Water Contents (OWC), and Optimum Fiber Contents (OFC). A series of test were performed on the fabricated specimen with OBC, OWC, and OFC. Tests include Marshall Stability, Indirect Tensile Strength, and Resilient modulus test. Comparison analyses were performed among EAM, Fiber modified EAM (FEAM), and typical HMA to verify the applicability of EAM and FEAM in the field. Test results indicated that both of EAM and FEAM have an enough capability to resist medium traffic volume based on the Marshall mix design criteria. Also the study found that fiber modification is effective to increase the load bearing capacity and moisture damage resistance of EAM.

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Study on the Ecological Restoration of Rock-exposed-cut-slope by Natural Topsoil Restoration Methods : In Case of Won-Ju Experiment (자연표토 복원공법에 의한 암절취비탈면의 생태적 복원에 관한 연구 : 원주사례지역을 중심으로)

  • Nam, Sang-Joon;Suk, Won-Jin;Kim, Nam-Choon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.2 no.4
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    • pp.54-63
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    • 1999
  • This study was conducted to suggest the ecological restoration and environmentally friendly revegetation technology for the rock-exposed cut-slopes by the Natural Topsoil Restoration Methods (NTRM) with the following restoration objectives; (1) prevention or reduction of wind and water erosion, (2) provision of food and cover for variety of animal species, (3) improvement of the visual or aesthetic quality of the disturbed slopes. On Nov. in 1995, the 5cm thick layer of artificial soil and 2cm thick layer of straw-mulching was attached at rock-exposed cut-slopes by NTRM without using anchor wire and anchor pin. The main results during four years surveying on the ground-coverage effect, plant growth, species diversity and importance values were summarized as follows. 1. Artificial soil attached at rock exposed cut-slopes was not eroded until recovered by tree and herbaceous vegetation in spite of not using anchor wire and anchor pin. Also it shows low soil hardiness and has almost the same amount of bacteria and fungi with in surrounding natural topsoil. 2. In 'combination for the woody vegetation', Lespedeza cyrtobotrya, Albizzia julibrissin, Rhus chinensis, Indigofera pseudo-tinctoria occupied upper layer vegetation. Since three years after seeding, Indigofera pseudo-tinctoria had overwhelmed the other woody plants and cool season foreign grasses, Erigeron canadensis, Taraxacum mongolicum, Commelina communis, Arundinella hirta (Thunberg) and Oenothera erythrosepala grows at lower part of the vegetation, 3. The heights of the Rhus chinensis grows 1.8m, Indigofera pseudo-tinctoria 2.0m, so it seems that the objectives of woody vegetation with native plants could be accomplished. 4. After 4 years later after seeding in 'combination for the herbaceous vegetation', the most dominant plant was Indigofera pseudo-tinctoria, the next was in order of cool-season grasses, Taraxacum mongolicum, Erigeron canadensis, lxeris dentata (Thunberg), Oenothera erythrosepala, Arundinella hirta (Thunberg). The diversity index in 'combination for woody vegetation' was higher than that in 'combination for the herbaceous vegetation'. The tendency of the intrusion of secondary succession plants was more effective in 'combination for the herbaceous vegetation' than in 'combination for the woody vegetation'.

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Efficacy of callus induced from Ullengdo niche plants for skin protection (식물세포배양기술을 이용한 울릉도 자생식물의 세포주 개발 및 피부세포 효능)

  • Choi, Yun Hui;Jung, Hae Soo;Cho, Moon Jin;Song, Mi Young;Seo, Hyo Hyun;Moh, Sang Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.8
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    • pp.5070-5077
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    • 2014
  • Many countries in the world have protected their native plants and utilized them as industrial materials in each country. In this aspect, it is increasingly important to develop cosmetics materials using native plants in Korea. Cosmetic materials have been developed with niche plants, such as Campanula takesimana Nakai, Dianthus superbus, Aster spathulifolius in Ullengdo, in which a specific plant distribution by distinct climate and environment was present. Water and ethanol extractions were performed from the calluses of Campanula takesimana Nakai, Dianthus superbus, Aster spathulifolius. HPLC analysis revealed different compositions and functions of effective elements in each ethanol extract. For example, all types of ethanol extracts showed an ability to heal wounds. In particular, the expression of the inflammation-related gene, COX-2, was decreased in response to the ethanol extracts of Dianthus superbus. These results indicate that the ethanol extracts from niche plants' calluses in Ullengdo are natural and environmentally-friendly compounds, and can be used as medical supplies associated with anti-inflammation and wound healing.

Application Case of Test Construction of Hydro-Seeding Measures with Seed-Fertilizer-Soil Materials on the Slopes Along the National Road Between Munduk and Wubokgu (문덕우복구간 국도비탈면 종비토뿜어붙이기 시험시공 적용사례)

  • Jeon, Gi-Seong;Woo, Kyung-Jin
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.10 no.6
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    • pp.130-138
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    • 2007
  • To protect the surface of ground-cutting slopes occurring at the national road substitute detour [roundabout road]construction jobsite between Munduk and Wubokgu within the jurisdiction of Pohang-si and environment-friendly road construction, a test execution of re-vegetation measures on the major slopes was done and the results are as follows : As a result of finding out the number of sprouting individuals on the test construction site, the average number of sprouting individuals on the three test spots by the method of revegetation measures D, revegetation measures A, and revegetation measures B was 1,292 number of per square meter, 1,190 number of per square meter, and 1,095 number of per square meter respectively, which statistics were higher than those of test spot by the revegetation measures C. As a result of finding out living plant's breeding index [weight in dried state], the average dried weight of living plant at the test spot by the method of revegetation measures B, in case of foreign herbal species, was the highest marking 8.96 grams per square meter, and the next was 6.86grams per square meter by the method of revegetation measures D, and the next after was 6.80 grams per square meter by the method of revegetation measures A, and the last 5.93 grams per square meter by the method of revegetation measures C. As a result of finding out the covering degree on the slopes, the same average covering degree of 80% and 77.5% in revegetation measures A and revegetation measures D individually, which showed a somewhat higher covering degree than those of revegetation measures B and revegetation measures C. As a result of finding out appearing plants on the test construction site, seeding plant life was found to be sprouting on all test spot while native and foreign herbal species and herbaceous plant as well as shrubs were growing in good harmony with each other. However, in case of revegetation measures B and revegetation measures C method, foreign plant species are dominantly growing. As a result of inspecting rifts on the slopes and the excavated state by water, there existed cracks in some of base materials only in revegetation measures C method applied spot.

Development of Environmental-friendly N-Acyl Taurates Manufacturing Process and Evaluation of their Physical Properties (N-Acyl Taurates의 환경친화적인 제조공정 개발 및 이의 물성 연구)

  • Park, Ji Na;Song, Ah Ram;Jeong, Yong Wu;Bae, Jae Heum;Ji, Heung Jin;Lim, Ho
    • Clean Technology
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    • v.11 no.4
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    • pp.195-204
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    • 2005
  • A new condensation process for manufacturing N-acyl taurates which generates less pollutant and produces more than 60 % yield in comparison with the conventional process has been developed in this work. Its optimum process conditions are at $210{\sim}230^{\circ}C$ of reaction temperature and 6 ~ 9 hour of reaction time when Parasol 123 of petroleum refired oil is employed as process solvent and mixed catalysts of sulfonic acid and phosphoric acid are utilized as process catalyst. And the qualities of N-acyl taurates produced by this new process are similar to or better than those of imported product judging from their acid value, amine value and color. Thus, it can be said that the newly developed process for manufacturing N-acyl taurates in this work is better than the conventional process. The physical properties of N-acyl taurates produced in this work such as surface tension, foaming power, foaming stability, hard water stability, and emulsifying power etc. were compared with those of commercially available anionic surfactants. And the experimental results show that N-acyl taurates shows good physical properties and that they can be alternative to conventional anionic surfactants.

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Forged Product Characteristic and Cold Rolling Simulation for High-Nitrogen Stainless Steel (HNS) (TP304계 고질소 스테인레스강의 단조특성과 냉간압연 모사)

  • Lee, M.R.;Lee, J.W.;Kim, B.K.;Kim, Y.D.;Shin, J.H.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2009.05a
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    • pp.310-313
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    • 2009
  • Several high nitrogen stainless steel ingots(100kg) were fabricated with changing Ni and $[N]_2$ contents by Pressurized Vacuum Induction Melting(P_VIM). After free forging process, chemical compositions, microstructure and mechanical properties were estimated. Hardness was increased with the increase of $[N]_2$ content. Furthermore, microstructure including a lot of tempering twins was observed with optical microscope. Mechanical properties were estimated as function of solution treatment temperature and cooling method(air/water) under duration time of 1 hr on sample that were fabricated with Ni content under the atmospheric $[N]_2$ pressure. At solution treatment range of $1050{\sim}1100^{\circ}C$, hardness was decreased with the increase of solution temperature and there were little discrepancy of microstructure and hardness with cooling method. Computer simulation was carried out in order to inspect pass schedule in cold rolling process. When the condition of simulation was roll speed of 2.5mpm, rolling rate $15{\sim}17%$ per pass, it was ascertained that the formation such as deformation by sticking and lamellar sliver etc. was restricted from a simulation.

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A Comparison of the Preference and Consumption Status of Non-Alcohol and Alcohol Beverages of Korean and Chinese University Students in the Jeonbuk Area (전북지역 한국대학생과 중국대학생의 일반음료와 알코올음료의 기호도와 섭취실태 비교)

  • Rho, Jeongok;Chang, Eunha
    • Korean Journal of Human Ecology
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    • v.21 no.4
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    • pp.805-817
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    • 2012
  • This study was conducted to investigate the preference and consumption status of non-alcohol and alcohol beverages of Korean and Chinese university students in the Jeonbuk area. Self-administered questionnaires were collected from 241 Korean and 198 Chinese students. Statistical data analysis was completed using SPSS v. 12.0. 'Water' was the most commonly consumed non-alcohol beverages by all Korean and Chinese students. The intake frequency of 'carbonated drink' (p<.001), 'fruits/vegetable juice' (p<.05), and 'vinegar drink' (p<.01) of Chinese male students was significantly higher than the Korean male students. The intake frequency of 'ionic drink' (p<.001; p<.01) of Korean male and female students was significantly higher than the Chinese male and female students. The intake frequency of 'fruits/vegetable juice' (p<.001), 'milk' (p<.01), and 'soymilk' (p<.05) of Chinese female students was higher than the Korean female students. For the choosing the non-alcohol beverages, the Chinese female students were more health-oriented than the Korean female students (p<.01). 'Beer' was the most commonly consumed alcohol beverages by the Korean male and female and Chinese male students whereas 'Wine' was the most commonly consumed alcohol beverages by the Chinese female students. The intake frequency of 'Soju' of Korean male (p<.001) and female (p<.001) students was higher than the Chinese male and female students. The intake frequency of 'Wine' of Chinese male (p<.05) and female (p<.001) students higher than the Korean male and female students. Compared with the Chinese female students, the Korean female students more funds have to spend, in order to buy alcohol beverages (p<.01). More 81% of the Korean male and 80% of the female students reported drinking alcohol in 'beer house' whereas 78% of the Chinese male and 65% of female students drunken the alcohol in the 'beer house' or at 'home' (p<.01; p<.001). In conclusion, a practically and foreigner-friendly alcohol policies of university should be devised to reduce the alcohol consumption of students and related problems.

A Study on Watertightness Improvement of Hybrid Method Using Polyvinyl Acetate(PVAc) (폴리비닐아세테이트(PVAc)를 이용한 복합공법의 수밀성능 향상에 관한 연구)

  • Ryou, Jae Suk;Song, Il Hyun;Lee, Yong Soo
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.16 no.4
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    • pp.18-24
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    • 2012
  • In this study, hybrid method using polyvinyl acetate (PVAc) which has a strong adhesion and flexibility in which acrylic copolymer chemical-reaction reacts with cement, and is eco-friendly, is to improve the watertightness. The hybrid method is applied applied primarily waterproof stuff comprising silicate system and secondary mortar mixed with PVAc on the concrete surface. And then, in order to evaluate the performance, the properties of bond strength and amount of water absorption were measured. Based on the above experiments, mock-up specimens for field application were fabricated, and then the properties were evaluated as laboratory experiments. As the results, specimens cast from hybrid method using PVAc showed the best results on watertightness and bond strength. And also, with respect to experiment of mock-up specimens, the properties were in agreement with laboratory results. Especially, it could know that PVAc has strengthening effect from the results of the compressive strength. Due to outstanding results of carbonation depth and resistance to chloride ion penetration, it may be applied in weak areas such as underground and marine structures.

Study on the Thermal Characteristics of Concrete Using Micro Form Admixture (마이크로기포제를 사용한 콘크리트의 열적 특성에 관한 연구)

  • Park, Young Shin;Kim, Jung Ho;Jeon, Hyun Kyu;Seo, Chee Ho
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.17 no.2
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    • pp.101-109
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    • 2013
  • Recently, it is certain that the increase of heating and cooling energy consumption by radical change in climate condition has caused serious problems related to environmental and energy concerns associated with increase of fossil fuel usage and carbon dioxide production as well as global warming. So, various actions to reduce greenhouse gas exhaustion and energy consumption have been prepared by world developed countries. Our government has also been trying to seek energy control methods for houses and buildings by proclaiming political polices on low-carbon green growth and construction and performance standards for environment-friendly housing. The energy consumption by buildings approximately reaches 25% of total korea energy consumption, and the increasing rate of energy consumption by buildings is stiffer than the rate by the other industries. The greatest part in the buildings of the energy consumption is building facade. While lots of research projects for reducing energy consumption of the facade have been conducted, but a few research projects on concrete comprising more than 70% of outsider of buildings has been tried. This research presents here a study to improve the insulation property of structural concrete formed by micro form admixture (MFA) with experimentally reviewing the physical, mechanical and thermal characteristics of the concrete. As the results of this experiment, in the case of concrete mixed with MFA, slump loss has been improved. As the mixing ratio of MFA increases, the compressive strength is decreased and thermal conductivity is increased. Also it was found that water-cement ratio increases, the compressive strength is decreased and thermal conductivity is increased. but, there was not big influence by the change of fine aggregate ratio.