• Journal of the Korea Society of Computer and Information
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• v.28 no.10
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• pp.171-178
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• 2023

In this paper, we propose a smart automated warehouse to maximize space utilization. Previous elevator-type automatic warehouses were designed with a maximum payload of 100kg on trays, which has the problem of extremely limiting the number of pallets that can be loaded within the space. In this paper, we design a smart warehouse that can maximize space utilization with a maximum vertical stiffness of 300kg. As a result of the performance evaluation of the implemented warehouse, the maximum payload was 500.6kg, which satisfied the original design and requirements, the lifting speed was 0.5m/s, the operating noise of the device was 67.1dB, the receiving and forwarding time of the pallet was 36.92sec, the deflection amount was 4mm, and excellent performance was confirmed in all evaluation items. In addition, the PLC control method, which designs the control UI and control panel separately, was integrated into the PC system to improve interoperability and maintainability with various process management systems. In the future, we plan to develop it into a fully automatic smart warehouse by linking IoT sensor-based logistics robots.

• Journal of Animal Environmental Science
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• v.18 no.2
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• pp.111-122
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• 2012

Establishment of the LFQC (Liquid Fertilizer Quality Certification) system is very urgent issue for recycling livestock manure as renewable resources in Korea faced with environmental problem of manure application to land due to intensive livestock farming. In this study, we investigated relevant laws and regulations on livestock manure fertilizer, certifications of eco-friendly agricultural products, government policies on livestock manure management to establish reasonable direction of Korean LFQC (Liquid Fertilizer Quality Certification) system. As a result from this study, the liquid fertilizers in 'LFQC' system could be classified as three levels according to the usage patterns in field; 1st. Individual Farm Level (IFL), 2nd. Joint Farm Level (JFL), and 3rd. Commercial Level (CML). And finally, we found some characteristics in 'Main Level-Grading Factors' of liquid fertilizer such as fertilizing value, harmfulness, stability, uniformity, economic effect, storage potential, commercial value, functionality. Those items were considered to be the key factors for the establishment of 'LFQC' system. More research on 'Evaluation Standards' for concrete guideline and on the 'Main Level-Grading Factors' be needed to complete Korean LFQC system.

• Journal of Science Education
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• v.44 no.1
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• pp.122-132
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• 2020

The purpose of this study is to examine the teacher expertise to be evaluated in the secondary science teacher employment test (TET, hereafter) in order to respond to changes in educational environments including the transition to competency-based curriculum, and ways to improve the first exam in major areas in the current TET. For this purpose, Delphi surveys and in-depth interviews were conducted with 18 professors of science education who have experience in the TET. According to the research results, teacher expertise such as subject teaching, student understanding, intelligence information utilization, community competencies, and so on were suggested. Ways to improve science content exam in the TET include securing fairness and validity by increasing the number of questions, strengthening the connection with the secondary school curriculum, updating assessment areas for certificate subjects periodically, etc. Ways to improve science education exam in the TET include research and development on the types of science education questions, introducing essay test to science education exam, development of a standardized curriculum on science education, etc. Based on the research results, the necessity of revising the curriculum for teacher training colleges, differentiating curriculum between teachers' colleges and natural science colleges, and reforming the teacher training system by introducing graduate school of education were suggested.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.6
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• pp.928-934
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• 2008

The objective of this study is to investigate the dyeing properties of safflower yellow dye on silk for the standardization of dyeing process and color reproducibility. Yellow colorants were water-extracted from safflower petals, concentrated, and freeze-dried to obtain colorants powder. The effects of dye concentration, dyeing temperature, and pH of dye bath were studied in terms of dye uptake and shade. Fastness to dry cleaning and light was evaluated. Dye uptake increased with raising temperature and brighter and more vivid yellow shade was obtained when dyed at $30^{\circ}C$. As colorants concentration increased, dye uptake increased progressively and the shade got darker and deeper. Maximum color strength was obtained at pH 3.5. It was speculated that the adsorption of colorants seemed to occur mainly by hydrogen bonding and physical force at pH 5.5 and by ionic bonding as well as hydrogen bonding below isoelectric point(pH 3.8-4.0). The results of reproducibility test showed acceptable color difference in the range of $1.11{\sim}2.01$. Washing fastness was fairly good as 4/5 rating, while light fastness was 2/3 rating.

• Journal of Korean Society of Transportation
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• v.21 no.4
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• pp.113-132
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• 2003

Using nonradial data envelopment analysis(DEA) under assumptions of strong disposability and variable returns scale, this paper annually estimates productive. technical and allocative efficiencies of three publicly-owned rail transit properties which are different in terms of organizational type: Seoul Subway Corporation(SSC, local public corporation), the Seoul Metropolitan Electrified Railways sector (SMESRS) of Korea National Railroad(the national railway operator controlled by the Ministry of Construction and Transportation(MOCT)), and Busan Urban Transit Authority (BUTA, the national authority controlled by MOCT). Using the estimation results of Tobit regression analysis. the paper next computes their true productive, true technical and true allocative efficiencies, which reflect only the impacts of internal factors such as production activity by removing the impacts of external factors such as an organizational type and a track utilization rate. And the paper also computes an organizational efficiency and annually gross efficiencies for each property. The paper then conceptualized that the property produces a single output(car-kilometers) using four inputs(labor, electricity, car & maintenance and track) and uses unbalanced panel data consisted of annual observations on SSC, SMESRS and BUTA. The results obtained from DEA show that, on an average, SSC is the most efficient property on the productive and allocative sides, while SMESRS is the most technically-efficient one. On the other hand. BUTA is the most efficient one on the truly-productive and allocative sides, while SMESRS on the truly-technical side. Another important result is that the differences in true efficiency estimates among the three properties are considerably smaller than those in efficiency estimates. Besides. the most cost-efficient organizational type appears to be a local public corporation represented by SSC, which is also the most grossly-efficient property. These results suggest that a measure to sort out the impacts of external factors on the efficiency of rail transit properties is required to assess fairly it, and that a measure to restructure (establish) an existing(a new) rail transit property into a local public corporation(or authority) is required to improve its cost efficiency.

• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.469-475
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• 2022

As the recent structure construction is constructed as a large-scale and deep underground excavation in close proximity to the building, the installation of retaining wall and supporters (Struts) has become complicated, and the number of supporters to avoid interference of the structural slab has increased. This construction process becomes a factor that causes an increase in construction joints of a structure, leakage and an increase in wall cracks. In addition, this reduced the durability and workability of the structure and led to an increase in the construction period. This study planned to dismantle the two struts simultaneously as a plan to reduce the construction joints, and corrected the earth pressure by assuming the reaction force value by the initial earth pressure and the measured data as the response ratio. After recalculating the corrected earth pressure through the iterative trial method, it was verified by numerical analysis that simultaneous disassembly of the two struts was possible. As a result of numerical analysis applying the final corrected earth pressure, the measured value for the design reaction force was found to be up to 197%. It was analyzed that this was due to the effect of grouting on the ground and some underestimation of the ground characteristics during design. Based on the result of calculating the corrected earth pressure in consideration of the response ratio performed in this study, it was proved analytically that the improvement of the brace dismantling process is possible. In addition, it was considered that the overall construction period could be shortened by reducing cracks due to leakage and improving workability by reducing construction joints. However, to apply the proposed method of this study, it is judged that sufficient estimations are necessary as there are differences in ground conditions, temporary facilities, and reinforcement methods for each site.

• Clean Technology
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• v.10 no.2
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• pp.73-87
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• 2004

In most of industrial fields, cleaning is employed for removing soils on their products or parts. Halogenated cleaning agents such as CFC-113, 1,1,1-TCE(1,1,1-trichloroethane), MC(methylene chloride) and TCE (trichloroethylene) have been used as cleaning ones in most of companies in the world since their excellent performance of cleaning ability and good material compatibility. However, CFC-113 and 1,1,1-TCE which are ozone destruction substances are not used any more in the advanced countries because of the which are ozone destruction substances are not used any more in the advanced countries because of the Montreal protocol. MC and TCE are now used restrictively at small part of industrial fields in most of countries since they are known to be hazardous or carcinogenic materials. Thus, it is indispensible that the alternative cleaning agents which are environmental-friendly and safe, and show good cleaning ability should be developed or utilized for replacement of the halogenated cleaning agents. Aqueous/semi-aqueous cleaning agents are evaluated to be promising alternative ones among various alternatives in environmental and economical view point. In this study, commercially available 12 aqueous and 6 semi-aqueous cleaning agents were selected and their physical properties, cleaning abilities, rinsing abilities and recycling of contaminated rinse water were measured and analyzed. Aqueous cleaning agents with higher wetting index showed better cleaning ability compared with those with lower wetting index. However wetting index did not have any correlation with cleaning ability in semi-aqueous cleaning agents. It was observed that soil concentration in aqueous and semi-aqueous cleaning agents should be maintained below the certain concentrations which depend on types of clearing agents. More than 70% soils in contaminated rinse water by some of aqueous and semi-aqueous clearing agents could be separated by simple settling method. This means that some cleaning agents with high oil-water separation efficiency will be effiective for recycling oil-contaminated rinse water. It was found that contaminated rinse water with aqueous agents was purified easiy by ultrafiltration method with PAN membrane of 30 kDa.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.12
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• pp.1688-1693
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• 2011

This study was evaluated mass production processes for flour noodles containing perilla leaf (FNPL) and to examine the antioxidant properties of FNPL. The processes for perilla leaf preparation before dough making were the main focus. The sensory evaluation was used as a tool to determine the optimal conditions for each step in the process. The appearance, taste, flavor, texture and overall acceptability were evaluated using a 9 point scale sensory evaluation. Eight minutes blanching of perilla leaf in boiling water (1:30, w/v) was found to be a suitable time to remove the unpleasant leaf flavor remaining in the final noodle product when fresh perilla leaf was used. The appearance, taste, texture and overall acceptability of FNPL were significantly different from FNPLs prepared with other blanching times. The appearance of FNPL containing 40% (w/v) perilla leaf homogenates was the best. In the dough making process, additional water was not required when 6 portions of 40% perilla leaf homogenate were added to 10 portions of flour, suggesting that the water adding step in the dough preparation process can be skipped. The antioxidant activity of FNPL was expressed as the radical scavenging activity. The DPPH ($IC_{50}$; 0.56 mg/mL), super oxide radical ($IC_{50}$; 9.53 mg/mL) and hydroxy radical scavenging activities ($IC_{50}$; 169.2 ${\mu}g$/mL) of FNPL were increased 19.6 (p<0.001), 1.4 (p<0.01) and 17.8 fold, respectively, compared to those for flour noodle (p<0.001). In conclusion, perilla leaf added to noodles at a final concentration of 19% (w/w) can increase the sensory and antioxidant properties of flour noodles.

• 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.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.1
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• pp.55-62
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• 2008

This study investigated the status and problems of marine-related environmental impact assessment and a utilization-consultation system in Korea and suggested improvement of the review organization. Also, it conducted SWOT analysis based on evaluation of functions, roles and performance of the marine environmental impact assessment center and proposed development strategies of the center through introduction of expert opinions and advanced systems. The performance statement-review by the center in 2007 included 358 cases in total; 165 (46.1%) for consultation on utilization of sea area, 104 for environmental impact assessment (29.0%), and 89 (24.9%) for prior environmental review. The consultation on utilization of sea area can be divided into that for public water surface-use (41%) and reclamation (32%), and sea aggregate extraction process (21%). Although bad impacts on marine environment are reducing under the current system, there are some limits and problems to supplement it in terms of content, system and operation. Review system on sea area utilization-impact(marine environmental impact assessment center) by marine environmental management law needs to obtain expertise, fairness and efficiency and, to do so, have operational supports and institutional improvement to maximize its own functions and roles. At the same time, it is necessary for the center to establish identity and the status as a professional review organization by setting active development strategies inside the center. Finally, it should strengthen an consultation system of marine environmental impact assessment led by the related ministry to achieve effective coastal management.