• Resources Recycling
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• v.3 no.2
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• pp.24-27
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• 1994

Rapid increases of bulky home electric appliances such as televisions, refrigerators, washing machines, etc are about to create many problems in their waste management in Korea. This paper summarizes the present status of the discarded appliances treatment including the estimations of their quantity, constituent materials, and recyclings.

• Fisheries and Aquatic Sciences
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• v.14 no.3
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• pp.230-233
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• 2011

To determine the cost-effectiveness of converting fish waste into liquid fertilizer, this study analyzed the production of 3 L of liquid fertilizer from the fermentation of fish waste. The total product cost of the fertilizer was calculated to be $165.26 for a one-batch operation. If the seed culture was repeated five times, the total product cost could be reduced to $36.39/L. According to this analysis, the reutilization of fish waste as liquid fertilizer was not particularly economically attractive at present, and plant-scale production would be necessary for commercialization. This is the first cost-effectiveness analysis of the bioconversion of fish waste into liquid fertilizer.

• Journal of environmental and Sanitary engineering
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• v.14 no.4
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• pp.29-34
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• 1999

1.The domestic waste generated in Iksan city was 177 tons a day last year. 27 tons of that were recycled daily. Due to increased awareness the recycling rate also increased. 2. It is preferred to get continuous publicity and to enforce the program steadily to activate exchange centers and places like a flea market for reusable things, which will lead to increase the life-span of the current designated landfill site. 3. Because burying food waste in underground will be prohibited from year 2005, the reutilization of food waste by feeding domestic animals like ducks and making artificial fertilizer are preferred. 4. The case of Iksan city is expected to be a model to other cities by establishing a display room to accommodate its detail work demonstration, displaying modeled utilization items and exchange center, incinerator, duck ranch, lawn ground, etc. for making a city as an environmental preservation city model.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.202-208
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• 2001

Aluminum dross should be recycled in consideration of characteristics of the dross and its reutilization after processing. In this study, aluminum dross generated in the domestic secondary aluminum industry was processed to use it as raw material for producing aluminum hydroxide. Sample dross was classified according to its size. The dross smaller than 1mm was leached with sodium hydroxide solution to extract the remaining aluminum from the dross into the solution, and then aluminum hydroxide precipitate was recovered from the leach liquor. Purity of the obtained aluminum hydroxide was above 98 percent, and particle size of the sample was in range of 3-39${\mu}{\textrm}{m}$. From the result, it was suggested that this process could be applicable to recycling of aluminum dross.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.381-384
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• 2005

The purpose of this study reutilization of waste fine tailing (FT) as admixture for cement and concrete. Various admixtures were made of Fine tailings and 2 Types of OPC, fly-ash and blast furnace slag. Cement mortars and concrete with FT are tested for fluidity and compressive strength. Also, the hydration reactivity of cement mortar with FT was examined by XRD and SEM morphology analysis. This work showed that the waste fine tailing could be effectively utilized as replacement materials of cement without any decrease in the strength if we can control the blaine of materials like cement, blast furnace slag and fly ash.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.297-300
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• 2004

The purpose of this study reutilization of waste fine tailing as admixture for cement. We observe tailing's basic properties such as shape, physical and chemical basic features. Also, various admixtures were made of 2 Types of tailings, OPC, fly-ash and blast furnace slag. The basic properties of the cement mortars incorporation with these admixtures were examined and analyzed under a verity of experimental conditions. This work showed that the tailing separated coarse materials could be effectively utilized as replacement materials of cement without any decrease in the strength if we can control the blaine of materials like OPC, slag and fly ash.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.8
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• pp.5-14
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• 2000

The treatment of technical consumer products after using is important for the conservation of our environment. In this paper the demanufacturing technology that is required to maximize the recycling rate of end-of-life products is introduced, The definitions including types of the recycling are described. The factors that have to regard in the design stage of products in order to maximize the recycling rate of the products are introduced. The objective assessment methods for the design for environment are described. Finally disassembly process and future prospect of the automations are discussed.

• Geomechanics and Engineering
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• v.29 no.2
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• pp.171-182
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• 2022

Reusing the used pile has not yet been implemented due to the unpredictability of the bearing capacity evolution. This paper presents an analytic approach to estimate the sides shear setup after the dissipation of pore pressure. Long-term evolution of adjacent soil is simulated by viscoelastic-plastic constitutive model. Then, an innovative concept of quasi-overconsolidation is proposed to estimate the strength changes of surrounding soil. Total stress method (α method) is employed to evaluate the long term bearing capacity. Measured data of test piles in Louisiana and semi-logarithmic time function are cited to validate the effectiveness of the presented method. Comparisons illustrate that the presented approach gives a reasonably prediction of the side shear setup. Both the presented method and experiment show the shaft resistance increase by 30%-50%, and this highlight the potential benefit of piles reutilization.

• Journal of Biomedical Engineering Research
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• v.45 no.2
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• pp.57-65
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• 2024

Recently, several studies have been conducted to lower the cost of transport of human by adding external joint stiffness elements. However, it has not been clearly elucidated whether adaptation time is required for human subjects to adapt to the added external joint stiffness. In this study, carbon plates in the form of shoe midsoles were added to the metatarsophalangeal joint, and the lower limb joint torque and mechanical energy consumption were compared before and after a total of 5 sessions (2.5 weeks) of running. A total of 11 young healthy participants exhibited higher elastic energy storage in carbon plates in the fifth session compared to the first session, and lower power in the ankle joint. This suggests that a single training session may be insufficient to validate the efficiency effect of added joint stiffness, and the human body seems to increase the elastic energy stored in the assistive joint stiffness and its reutilization.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.1
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• pp.54-59
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• 2011

This test established the bioavailability and sample input by mixing the maintaining the microbial machine parts and food waste leachates in weight of 2:1 as advanced experiment, maintaining the constant temperature, agitating and observing its weight and property change for 60 hours. And, I injected daily the established microbial machine parts and food waste leachates rate, maintained the temperature in the reactor with $55{\sim}65^{\circ}C$, and agitated with constant speed. I studied the recycling possibility of food waste leachates by extracting the sample after 24 hours, verifying its characteristics, and repeating the food waste leachates input and sample extraction for about 40 days. Considering all about the results of this study, I saw that 87.32% of food waste leachates was reduced, and the solid of bluebug or food included in the food waste leachates was decomposed within 24 hrs. pH for 43 days after 9 days of stabilization period was maintained from 3.7~3.9 and the ignition loss from 88.67~87.3%, and the quantity of organic matter from 77.6~80.88%. With the similar result daily maintained, it is considered to progress more the minimization by inputting the future food waste leachates. C/N rate satisfies the less than 25 that is the composting basis within 8 days, maintaining between 13~15, with 2% of salt not exceeded, it is able to recycle as the compost of food waste leachates as based on the composting with no extracted heavy metal content.