• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.6
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• pp.40-45
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• 2016

It should be noted that the use of the lathe scrap for making fiber reinforced cementitious composites raised friendly environmental effect as well as economy because the lathe scrap is a by-product of steel manefactures and is occurred when lathe and milling works of them are conducted to process steel manufactures. Thus, the purpose of this experimental research is to investigate workability and strength characteristics of lathe scrap reinforced cementitious composites(LSRCCs). For this purpose, three types of lathe scraps were collected from processing plants of metal, and then LSRCCs containing these were made for 2mm width and 40mm length. As a result, it was observed from the test results that the workability of LSRCCs was slightly decreased than plain mortar and the flexural strength of LSRCCs were much larger than these of plain mortar and effect of types of lathe scrap on the characteristics of LSRCCs were somewhat large.

• Parasites, Hosts and Diseases
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• v.21 no.2
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• pp.187-192
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• 1983

In order to clarify infestation Pattern for the encysted larvae of digenetic trematodes from fresh-water fishes, this survey was carried out from March to September, 1983. A total of 380 fishes of 32 species wore collected with netting at the three reaches, upper, middle and lower in Mangyeong riverside area. After the fishes were dissected into small scraps, they were pressed under cover glass and examined-for the presence of those of digenetic trematodes with a microscope. The resillts obtailled were as follows; Out of a total of 380 knishes inspected, 320 fishes(84%) from 31 species were found positive with, digenetic trematode metacercariae; more than 10 species of the metacercariae Ivere detected in Pseuderasbora parva; .Gnnthepegen mtajimae, Microphysogokio yaluensis, Cultriculus eigenmanni and Gnnthopogon coreanus (more than 8 species) ; Aphyocypris chinensis (8 species) and etc. respectively. Clonorchis sinensis metacercariae were found positive from 93 fishes (25%) from 12 species and detection rates in other species of digenetic trematode metacercariae from various fishes were; Exorchis oviformis, 261 fisles (57%) from 28 species; Cyathocotyle criensalis, 47 fishcs (12%) from 12 species; Metorchis orientalis, 21 fishes (6%) from 12 species; Metagonimus yokogawai, 164 fishes (43%) from 26 species; Pseudesorchis major, 71 fishes (19%) from 18 species; Metacercaria haiegawai, 77 fishes (20%) from 25 species; Centrocestus armatus, 24 fishes (6%) from 7 species; Echinochasmus japonicus, 2 fishes (0.5%) from 2 species, and unidentified species, 34 fishes (9%) from 15 species respectively. The sums of average number of the encysted larvae of all species found in fish body/gram showed 83 in P.parva, Cobitis taenia (74.2), A. chinensis (28.5), Pseudoperilampus uyekii (26.6), G. majimae (19.6) and etc. respectively and the average peak number of each metacercaria in fish body/gram showed 21.7 C. sinensis, 245. ovifcrmis, 15, 3 M, crientalis and 6.1 5. japonicus in P. parva. 42.7 C. orientalis and 25.1 M. yohogawai in C. taenia; 8.3 C. armatus and 8.3 M. hasegawai in P. uyekii. 6.3 P. major in Carassius carassius, and 2.9 unidentified species in G, niajimae respectively.

• Resources Recycling
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• v.24 no.1
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• pp.43-50
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• 2015

An extensive literature survey and personal communication with relevant experts made it possible to understand economic and technical feasibility of disposable diaper recycling. Commercial level of soiled diaper recycling technology is currently available from a Dutch company, Knowaste Co., who owns a proprietary separation technology of the pulps, plastics and super absorbing polymer (SAP). In Korea, on the other hand, pre-consumer diaper recycling technology without material separation at its infancy converts manufacturing scraps into refuse plastic fuel (RPF), container/truck cargo boards or automobile boards/sheets. Although previous studies on feasibility of post-consumer recycling in Korea showed mutually contradictory implication, it was found out in this research that significantly positive economic feasibility can be obtained with pre-consumer diaper recycling. Subsequent recycling R&D including pre-consumer scrap and policy support may expedite 'Establishment of Sustainable Society.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.1
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• pp.35-41
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• 2006

The steel foundries with electric arc furnaces handling metal scraps have recently gained an attention as a potential source of dusts. The present study focuses on the analysis of dust emissions and removals during furnace charging and melting processes by commercial CFD software named FLUENT. A body fitted grid system consisting of 880,000 meshes was first generated by Gambit for the electric arc furnace with the capacity of 60 ton/cycle and then FLUENT was invoked to solve the corresponding NavierStokers equation for the momentum, temperature and dust concentration. The entire processes from metal charging to metal melting were simulated to investigate the unsteady behaviors of fluid flows and dust concentrations. The model simulation results showed that as the top of the electric arc furnace opened for metal charging, hot plumes bursted out from the furnace rose strongly by buoyance and escaped mostly through the main hood. Therefore, the capacity of main hoods determined the vent efficiency in the metal charging process. As the furnace was closed after the metal charging and the metal melting processes was followed, the hot flow stream stretching from the furnace to the main hood was dissipated fast and the flow from the inlet of the bottom of the left hand side to the main and monitoring hoods constituted the main stream. And there was only a slow flow in the right hand side of the furnace. Therefore, the dust concentrations were calculated higher in the left hand side of the furnace, which was consistent with observations.

• Resources Recycling
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• v.27 no.1
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• pp.22-30
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• 2018

In order to industrially recycle nickel, cobalt and rare earth elements included in waste NiMH batteries, electrode powder scraps were recovered by dismantle, crushing and classification from automobile waste battery module. As a result of leaching recovered electrode powder scrap with sulfuric acid solution, 99% of nickel, cobalt and rare earth elements were leached under reaction conditions of 1.0 M sulfuric acid solution, pulp density 25 g/L and reaction temperature $90^{\circ}C$ for 4 hours. In addition, the rare earth elements were able to separate from nickel / cobalt solution as cerium, lanthanum and neodymium precipitated under pH 2.0 using 10 M NaOH.

• Resources Recycling
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• v.27 no.1
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• pp.38-44
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• 2018

A large amount of Nd-Fe-B magnet scraps are generated during magnet manufacture process. In this study, selective chlorination of the rare earth elements by hydrogen chloride gas which obtained from the pyrolysis of polyvinyl chloride (PVC) was investigated. In thermogravimetric analysis, drastic weight loss was occurred at about 500 K and 710 K. At the isothermal experiments, the weight loss reaches about 30% above 673 K. XRD patterns characterized that after each experiments, ${\alpha}$-Fe, Nd oxychloride, Nd chloride, and Fe chlorides were formed, and the leaching residues remain only ${\alpha}$-Fe. The yields of Nd, Dy, and Fe for the isothermal experiment were increased with temperature and peaked at 873 K. As PVC ratio increased, the yields of Nd, Dy and Fe were also increased.

• Journal of the Korea Fashion and Costume Design Association
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• v.16 no.3
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• pp.219-238
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• 2014

This study attempted to investigate present condition and product planning of global eco-fashion brands that harmonize fashion and sustainability. As research subjects, this study selected 97 oversea fashion brands mentioned in books related to eco-fashion, Black(2011), Brown(2010), Fuad-luke(2009). As for research methods, materials and ethical practices of these selected 97 brands through literature data and their internet site homepages. This study analyzed oversea eco-brands collected 26 British brands, 22 American brands, 36 European brands such as Germany, France, Italy, Sweden, Spain, Finland and so on, except Britain and 13 other regions including Japan, India, Canada, Mexico, and New zealand. In conclusion, the product planning characteristics of these oversea eco-fashion brands can be summarized as follows; community and fair trade, ecological and slow design, recycle, reuse, redesign, and new eco-models. Firstly, brands of 'community and fair trade' manufactured products through fair trade and local community's artisan by ethical practices with organic fabrics. Secondly, brands of 'ecological and slow design' pursued timeless design and multi-functional design as luxury eco-fashion styles. They used organic textiles, hemp, bamboo, soya, tencell, sea cell, and self-sustaining plants. Thirdly, brands of 'recycle, reuse, redesign' aimed for upcycling high-end fashion and used vintage clothes, textile scraps, PET, parachutes, tires, safety belts, advertising banner and so on. In addition, brands of 'new models as eco-fashion' suggested zero-waste cutting, recycling over-printing technology, new sustainable business model, and ethical practices in the supply chain of the fashion industry.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1429-1436
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• 2011

In this paper, a new tube-radius-measuring algorithm has been proposed for effectively measuring the radii of small tubes under severe noise conditions that can also perform well when metal scraps that make it difficult to measure the radius correctly are inside the tube hole. In the algorithm, we adopt a fuzzy searching method that searches for the center of the inner circle by using fuzzy parameters for distance and orientation from the initial search point. The proposed algorithm has been implemented and tested on both synthetic and real-world tube images, and the performance is compared to existing circle-detection algorithms, such as the Hough transform and RANSAC methods, to prove the accuracy and effectiveness of the algorithm. From this comparison, it is concluded that the proposed algorithm has excellent performance in terms of measurement accuracy and computation time.

• Clean Technology
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• v.23 no.3
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• pp.256-269
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• 2017

In response to national and international regulations for resource circulation and to reduce greenhouse gas emissions, the automotive industry has tried to reuse scrap parts and defective products produced in the disposal or production stages as recycled resources. Attempts have been made to reach the target recycling rate by reducing the number of material types required for each part. Moreover, in order to achieve greenhouse gas reduction targets while maintaining the performance of existing products, lighter components are being developed. Existing products were 100% incinerated at the disposal stage, but the uni-materialized products were improved to be possible that it could be recycled 90% through scraps and the defective product in the pre-production and production stage. It also appears that the fuel efficiency improves through 56% lightweight compared to the existing product. In this paper, a preliminary assessment is conducted on the applicability of uni-materialized product development of car parts. The environmental impact values of existing products and developed prototypes are compared and analyzed through life cycle assessment.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.11 s.176
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• pp.45-50
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• 2005

In this study, the casting/forging process was applied in manufacturing a low control arm, in order to prove that application of casting/forging process to Al6061 is likely to get the effect of light weight compared with existing steel products and to reduce the cost of materials. Firstly, In order to set up the optimum casting condition of the forging material, Al6061, casting experiments were carried out by controlling pouring temperature of the aluminum for casting, mold temperature, and pouring time. $700^{\circ}C$ pouring temperature, $300^{\circ}C$ mold temperature and 10-second pouring time were taken into account as the optimum casting conditions. With respect to a hot forging test, it is practiced on the basis of a temperature of materials, strain rate, and reduction rate so as to observe each microstructure and examine strain-stress curve simultaneously; examine tensile test and hardness test; eventually set up the optimum hot forging condition. A hot forging test, tensile test, hardness experiment, and microstructure observation were carried out on condition of $70\%$ reduction rate, $500^{\circ}C$ temperature of materials, and 1 strain rate. As a result of those experiments, 330MPa tensile strength, $16.4\%$ elongation, and 122.8Hv hardness were recorded. In oder to get a sound preform which has no unfitting cavity and less flash, two preforms were proposed on the basis of volume rate of the final product; the optimum volume rate of preform for the low control arm was $115\%$. In conclusion, it is confirmed that using the forging material rather than casting materials in casting/forging process is likely to get more superior mechanical properties. Compared with Al6061, performed by means of general forging, moreover, cast/forged Al6061 can not only stimulate productivity by reducing production processes, but cut down the cost of materials by reusing forging scraps.