• Resources Recycling
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• v.25 no.6
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• pp.58-64
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• 2016

Paper industry discharges many by-products and quantity of PSA (Paper sludge ash) has been increased. In this study, hydration water was added to PSA for use as cement admixture. PSA with added water was mixed with anhydrite and this mixture was used as cement substitute. Physical properties of PSA cement were changed by contents of PSA, but PSA cement containing PSA less than 10% had similar properties to those of OPC. Compressive strength of PSA cement mortar had a certain relationship with $Ca(OH)_2$ content. Compressive strength at 3 days increased, as $Ca(OH)_2$ content increased. However, the strength at 28 days increased, as $Ca(OH)_2$ content decreased.

• Journal of agriculture & life science
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• v.44 no.3
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• pp.7-14
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• 2010

Alternative subirrigation way, capillary wick system (CWS) was tested to reduce labor cost, waste water, contamination of ground water, and use of fungicide compared to overhead irrigation system (OIS). CWS helped reduce remarkably the working hours for watering from 4 hours in OSI to just 5 minutes. Labor cost was saved 98% in CWS compared to OIS. By the physical characteristics of various growing media, 1 coconut coir+2 perlite (v/v) mixture was selected because it had an ideal distribution of three phase, e.g. 1 solid: 1 liquid: 2 gas phase. Medium mixture containing scoria had so high bulk and particle density to hurt root. In bark-containing medium, the liquid phase and the percent saturation of liquid phase with time elapsed was lower than that of other mixture. It meant that the mixture contained very low level of water. Application of CWS for cyclamen pot production played an important role in reducing the incident of fusarium wilt symptom from 18% in conventional over watering system to 4%. Cyclamen pot irrigated by capillary wick had shorter petiole and more leaves than those by overhead watering. As a result, this system was highly beneficial to get uniform pot products with high quality. It improved water and nutrient solution efficiency relative to conventional overhead irrigation system (OIS).

• Advances in concrete construction
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• v.3 no.1
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• pp.55-69
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• 2015

Tailing Material (TM) and Fly Ash (FA) are obtained as waste products from the mining and thermal industries. Studies were carried out to explore the possibility of utilizing TM as a part replacement to fine aggregate and FA as a part replacement to cement, in concrete mixes. The effect of replacing fine aggregate by TM and cement by FA on the standard sized specimen for compressive strength, split tensile strength, and flexural strengths are evaluated in this study. The concrete mix of M40 grade was adopted with water cement ratio equal to 0.40. Concrete mix with 35% TM and 65% natural sand (TM35/S65) has shown superior performance in strength as against (TM0/S100, TM30/S70, TM40/S60, TM50/S50, and TM60/S40). For this composition, studies were performed to propose the optimal replacement of Ordinary Portland Cement (OPC) by FA (Replacement levels studied were 20%, 30%, 40% and 50%). Replacement level of 20% OPC by FA, has shown about 0-5% more compressive strength as against the control mix, for both 28 day and 56 days of water curing. Interestingly results of split tensile and flexural strengths for 20% OPC replaced by FA, have shown strengths equal to that of no replacement (control mix).

• Nuclear Engineering and Technology
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• v.40 no.4
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• pp.311-318
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• 2008

In modem power reactors, nuclear fuels have recently reached 55,000 MWd/MtU from the initial average burnup of 35,000 MWd/MtU to reduce the fuel cycle cost and waste volume. At such high burnups, a fuel pellet produces fission products proportional to the burnup and creates a typical high burnup structure around the periphery region of the pellet, producing the so called 'rim effect'. This rim region of a highly burnt fuel is known to be ca. $200\;{\mu}m$ in width and is known to affect the fuel integrity. To characterize the local burnup in the rim region, solid sampling in the micro meter region by laser ablation is needed so that the distribution of isotopes can be determined by ICP-MS. For this procedure, special radiation shielding is required for personnel safety. In this study, we installed a radiation shielded laser ablation ICP-MS system, and a performance test of the developed system was conducted to evaluate the safe operation of instruments.

• Mass Spectrometry Letters
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• v.9 no.4
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• pp.91-94
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• 2018

Bilin tetrapyrroles are metabolic products of the breakdown of porphyrins within a species. In the case of mammals, these bilins are formed by the catabolism of heme and can be utilized as either biomarkers in disease or as an indicator of human waste contamination. Although a small subset of bilin tandem mass spectrometry reports exist, limited data is available in online databases for their fragmentation. The use of fragmentation data is important for metabolomics analyses to determine the identity of compounds detected within a sample. Therefore, in this study, the fragmentation of bilins generated by positive ion mode electrospray ionization is examined by collision-induced dissociation (CID) as a function of collision energy on an FT-ICR MS. The use of the FT-ICR MS allows for high mass accuracy measurements, and thus the formulas of resultant product ions can be ascertained. Based on our observations, fragmentation behavior for hemin, biliverdin and its dimethyl ester, phycocyanobilin, bilirubin, bilirubin conjugate, mesobilirubin, urobilin, and stercobilin are discussed in the context of the molecular structure and collision energy. This report provides insight into the identification of structures within this class of molecules for untargeted analyses.

• Journal of the Korean Society of Clothing and Textiles
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• v.43 no.1
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• pp.138-153
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• 2019

This study aimed at exploring the system of reverse logistics for clothing, which refers to the whole process of moving clothes from their final destination for the purpose of capturing value or for proper disposal. In-depth interviews were conducted with stakeholders of reverse logistics system for clothing. Out of 51 individuals contacted, 12 participated in the research, resulting in 23.5% response rate. All the stages in Korean reverse logistic system for clothing were identified, but the flow of the resources in the system was not smooth and the collectors were often illegal or unauthorized companies. Domestic markets for reused or refurbished clothing were limited, and most of the products on this stage were exported. In general, collectors and exporters of reused clothes emphasized economic value over environmental value in their business when compared to manufacturer. Most participants acknowledged the importance of information exchange, but little social interaction was found among stakeholders.

• Advances in concrete construction
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• v.12 no.6
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• pp.469-477
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• 2021

Keratin fibres are waste products of the poultry industry. Natural materials made from chicken feather fibres (CFFs) are used in concrete-reinforced composites in this study. Brittleness is a major problem of high-strength concrete (HSC) that leads to sudden failure at the ultimate capacity of concrete. Hence, this work aims to investigate effects of using CFFs on improving the brittle behaviour of HSC. Two scenarios are performed to analyse the effectiveness of using CFFs. HSC containing different ratios of CFF (0% as the control, 0.5%, 1%, 1.5%, 2%, and 3%) by volume are tested in the first scenario. Glass fibres (GF) are used to replace CFFs in the other scenario. Tests of fresh, hardened and morphological properties for concrete are performed. Results showed the enhanced brittle behaviour of HSC when using both types of fibres. The preferable ratio of both types of fibres is 1% by volume. Flexural and splitting tensile strengths increased by about 44.9 % and 42.65 % for mixes containing 0.1% GF, respectively. While they were increased by about 21.6 % and 21.16 % for mixes containing 0.1% CFF, respectively.

• Advances in concrete construction
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• v.12 no.5
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• pp.419-427
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• 2021

The overuse level of cement for civil industry has several undesirable social and ecological consequences. Substitution of cement with industrial wastes, called by-products, such as fly ash, ground granulated blast furnace slag, silica fume, metakaoline, rice husk ash, etc. as the mineral admixtures offers various advantages such as technical, economical and environmental which are very important in the era of sustainability in construction industry. The paper presents the experimental investigations for assessing the mechanical properties of the concrete made using the Pozzolanic waste materials (supplementary cementitious materials) such as fly ash and silica fume as the cement replacing materials. These materials were used in eight trial mixes with varying amount of ordinary Portland cement. These SCMs were kept in equal proportions in all the eight trial mixes. The chemical admixture (High Range Water Reducing Admixture) was also added to improve the workability of concrete. The compressive strengths for 7, 28, 40 and 90 days curing were evaluated whereas the flexural and tensile strengths corresponding to 7, 28 and 40 days curing were evaluated. The study corroborates that the Pozzolanic materials used in the present investigation as partial replacement for cement can render the sustainable concrete which can be used in the rigid pavement construction.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.2
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• pp.127-132
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• 2022

The growth of e-commerce market requires more delivery packagings, which protect goods from the damage factors on the delivery. In this study, we have analyzed the distribution environment data (vibration and impact) measured in previous study and compared with global standards (ISTA, ASTM), so that we developed the testing method for Field-to-Lab simulation suitable to the domestic delivery. In order to verify the efficacy of this method, we took the Field-to-Lab tests for 3 packaged products (detergents set, glass tableware set, small furniture), which has been frequent breakages or damages on the actual delivery by e-commerce order, so that we could find out the test results were similar to those of the actual delivery occasions. In addition, we could perform redesign and improvement of the parcel delivery packagings for safe transportation by taking this Field-to-Lab test repeatedly. This test methods was finally proposed to be Korean industrial standard (KS), and is expected to be useful as a designing tool for the packaging optimization between protecting goods and reducing packaging waste.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.26 no.1
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• pp.61-68
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• 2023

In North Korea, the production of courage tombs continues, and it is known that the activity rate is higher than that of old tombs. However, pot seedling are planted using hoes and shovels used for planting old tombs with exposed roots and low activity rates. This is believed to result in excessive force when stepping on the container grave with a hoe in the planting process, resulting in the collapse of the container grave or the waste of labor due to the creation of unnecessary planting holes. Therefore, when planting courage graves at North Korean afforestation sites, it is necessary to improve the work of making planting holes using general hoes in a way that improves labor productivity in a more efficient manner. As part of inter-Korean technical cooperation to improve the North Korean afforestation method, this study was conducted with the aim of developing efficient container seedlings and using them for North Korean forest restoration projects. It is believed that developing planting equipment exclusively for container graves for forest restoration in North Korea in South Korea and providing equipment and production technology to North Korea can contribute to the development of forest restoration technology in North Korea. If the Yonggeomyo Development Planting Equipment is provided to North Korea, it will be a realistic inter-Korean forest cooperation project to avoid international sanctions by recognizing the excellence of the development products by directly using its own materials through technical cooperation.