• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.05a
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• pp.160-164
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• 2007

In the steel industry, there is a need to produce large forged parts for the automobile industries, the flight and shipping industries ad military industries. In the steel-industry application, a cogging technique for cast ingots is required, because the major parts are needed as one large body in order to obtain higher quality. Therefore, cogging process is the primary step in manufacturing of practically large open-die forging. In the cogging process, internal voids have to be eliminated as defects, The present work is concerned with the elimination of the internal voids in large ingots so as obtain sound products. In this study, hot compression tests were carried out to obtain the flow stress of cast microstructure at different temperature and strain rates. The FEM analysis are performed to investigate the overlap defect of cast ingots during cogging stage. The measure flow stress data were used to simulate the cogging process of cast ingot using the practical material properties. Also the analysis of void closure are performed by using the $DEFORM^{TM}$-3D. The calculated results of void closure behavior are compared with the measured results before and after cogging, which are scanned by the X-ray scanner. From this result, the criteria for deformation amounts effect on the void closure can be investigated by the comparison of practical experiment and numerical analysis.

• Journal of Conservation Science
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• v.33 no.5
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• pp.381-390
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• 2017

Desalination is the main focus of the stabilization of iron artifacts. However, drawbacks such as re-corrosion are noted due to the uncertainty in the elimination of the corrosive factors and artifacts. Several studies have been carried out on the effects of corrosion inhibitors to overcome these shortcomings. In this study, the effects of type 3 water treatment on corrosion inhibitors were investigated. Surfaces of samples that contained film corrosion inhibitors on their surfaces were analyzed. The results revealed that the surface rust was removed from the sample of type 1 No. 2 that was mainly composed of phosphate. The average weight reduction rates of re-corrosion samples were 0.58, 0.03, and 0.07% for type 1 No. 2, type 2 No. 2, and type 3 No. 2 respectively. The changes in the $Cl^-$ ion, a corrosive agent were found to be 28.60, -4.08, and -1.94 ppm for type 1 No. 2, type 2 No. 2, and type 3 No. 2 respectively. The water-treated films were analyzed by X-ray photoelectron spectroscopy (XPS). It was found that type 2 No. 2 had less Fe the basis metal, than that in type 3 No. 2 indicating much better film. Moreover, Si content was higher in type 2 No. 2, based on the silicate content, than in type 3 No. 2. They are speculated to be the reason or the formation of a better film. Type 1 No. 2, which is mainly composed of phosphate, would be inappropriate as a metal artifact conservation treatment. It was determined that type 2 No. 2 and type 3 No. 2 water treatments, which are mainly composed of silicate, provided excellent corrosion inhibiting effects. Corrosion inhibitors could be used as emergency treatment agents during the excavation of iron artifacts.

• Journal of Environmental Impact Assessment
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• v.28 no.6
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• pp.549-555
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• 2019

The purpose of this study is to ensure optimal operating conditions for improving the removal efficiency of phosphorus (P) and nitrogen (N) that are the causative agents of eutrophication by utilizing functional media. The main ingredients of the functional media used in this study are Si, Al, and Fe, SiO₂, KAlSiO₃O₈, Al₂O₂·2SiO₂O, H₃Al₂Si₂O₉, Fe₃O₄O), and berylite. To identify the maximum efficiency of the filtration process, the processing efficiency experiment was carried out according to flow method, velocity, and thickness of residual media. The flow method carried out two experiments, 50 m/day, 100 m/day, 150 m/day, 200 m/day, 250 m/day, and 20 cm, 40 cm, 50 cm, 60 cm, 80 cm of lead depth. Experiments have shown that SS, T-N, and T-P all showed higher elimination efficiency of the upflow current conditions than the downflow current conditions, and that the processing efficiency of the linearity is the highest at SS 50 m/day, T-N 150 m/day and T-P 100 m/day. In addition, the analysis of the removal efficiency according to the residual thickness showed that SS, T-N, and T-P all showed the highest efficiency at 60 cm. In addition, the analysis of the removal efficiency according to the residual thickness showed that SS, T-N, and T-P all showed the highest efficiency at 60 cm. It is considered desirable to set the top-down flow conditions and residual thickness of 60 cm and adjust the velocity of the line according to the target media for removal.

• Korean Journal of Community Nutrition
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• v.7 no.6
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• pp.833-843
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• 2002

This study was carried out to investigate the effect of hygiene education on the microbiological changes of processing utensils and the environmental in the manufacture of cereals and to evaluate the Cd, Pb contents and nutrient compositions of 11 cereals. The result of microbiological evaluation was that fungi, coliforms and staphylococcus species were detected in employees, on equipment, utensils and environments in the first inspection. Fungi were detected in most of the cereals, staphylococcus species were detected in soybeans, perilla seeds and sea tangle How, and bacillus cereus was detected in sorghum and black sesame seeds. The water content of rice, barley, glutinous rice, brown rice and carrot flour in packaged products, and in carrot flour, angelica keiskei, carrot, sea mustard and potato in bulk products was in excess of 8.0%. The Pb content of cereals was 0.14-0.51 mg/kg and Cd was not found. The acid value of Job s tears flour and black sesame seed flour was higher than 5.0 mg/g oil. Cereals were manufactured from 41 different cereals and grains, legumes, seeds and nuts, vegetables, potatoes, seaweeds, fruits, glucose and salt. The average content of cereals and grains, legumes, and seeds and nuts in cereals was 75.75%, 16.19% and 4.93%, respectively. The mean nutrient content per 100 g of cereals was calories 365.8kcal, protein 13.3 g, fats 5.9 g, carbohydrates 63.4 g, Ca 91.8 mg, p 269.9 mg, Fe 3.15 mg, Na 76.2 g, K 421.8 mg, Zn 2.33 mg, Vit. A 12.5 R.E., Vit. B$_1$0.23 mg, Vit. $B_2$ 0.16 mg, Vit. $B_6$ 0.46 mg, Niacin 3.5 mg, Vit. C 1.36 mg, folic acid 62.3 $\mu$g and Vit. E 1.24 mg. When nutrients value of 48 g of cereals and 200 $m\ell$l of milk was compared to 1/3 of the RDA, the values were below than 60% of 1/3 of the RDA except Na, K, Vitamin $B_1$ and C contents. The average carbohydrate : protein : fat ratio of energy intake was 54.27 : 17.45 : 28.28, respectively. Therefore, a training program consisting of the education of the staff in surveillance and standard operating procedures, the elimination of dangerous procedures, sanitation checklist, the implementation of Preparation methods and standard recipes for cereals is required.

• Journal of the Mineralogical Society of Korea
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• v.15 no.2
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• pp.85-94
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• 2002

XRF, XRD, EPMA have been used to investigate microstructures and mineralogical changes caused by the faulting and fluids associated with faulting in the Quaternary fault gouge zones at the Sangchon, Ipsil and Wangsan faults located at the southeastern part of the Korean Peninsula. The chemical compositions of faulted rocks and protoliths analyzed by XRF show that the fault gouges are relatively enriched in TiO$_2$, P$_2$O$_{5}$, MgO, and Fe$_2$O$_3$) compared with protoliths, indicating that the fluids associated with faulting were highly activated. XRD results show that the fault gouges predominantly consist of quartz, feldspar, calcite and clay minerals. Clay minerals formed in the gouge zones are mainly composed of smectite characterized by a dioctahedral sheet. Based on EPMA analyses various kinds of sulfide, carbonate, phosphate minerals were identified in the gouge zones and protoliths. Xenotime of grey fault gouge of the Sangchon fault and sulfide minerals of contact andesitic rock of Ipsil fault and contact grey andesitic rock of Wangsan fault were probably formed by inflow of hydrothermal solution associated with faulting prior to the Quaternary. Carbonate minerals of contact andesitic rock and gouge zone of the Ipsil fault were formed by inflow of fluid associated with faulting prior to the Quaternary. They are heavily fractured and have reaction rim on their edge, indicating that faultings and inflow of fluids were highly activated after carbonate minerals were formed. Calcites of Wangsan fault seemed to be formed in syntectonic or posttectonic Quaternary faulting.g.

• Proceedings of the Technology Innovation Conference
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• 1997.07a
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• pp.222-223
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• 1997

By analyzing the successful innovation case of potato microtuber mass production technology, a representative case of technology-push type creative innovation in an imitation oriented research culture, this paper attempts to figure out conceptual model of creative innovation that is initiated by the public laboratories in catching-up country, Stages of creative innovation can be divided into the internal R&D stage and the external commercialization stage. Success of the internal R&D stage depended on autonomy to secure creative research idea and commitment of individual researchers. Psychological pressure evoked from sportlights of mass media and commitment of sponsor increased the intensity of research efforts of the researcher Recognition of research problem and its significance was intensified by site visits of agricultural fields, and the recognized higher impacts of expected research results and knowledge creation achieved were a fundamental source of self-motivation. In the stage of commercialization stage, various legal, socio-economic, and psychological barriers were confronted. In a catching-up country lacking of experiences of creative innovation, creative innovation process can be regarded as a barrier elimination and cultural revolution process. Among the barriers, psychological refusal of farmers to corn-sized potato seeds was critical, which finally enforced to further researches to enlarge the size of potato seeds. In addition, the researcher has concentrated his research efforts in one specialized research area by getting a series of similar research project funds rather than diversification. It was lucky for him to have a chance to carry out a series of similar researches in one research area during the last 10 years. In getting research funds from government and private companies continuously in one research area, both internal and external promoters played significant roles.

• Korean Journal of Soil Science and Fertilizer
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• v.8 no.3
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• pp.135-152
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• 1975

The following informations are known from physical and chemical characteristics of orchard soils and nutritional diagnosis of orange leaves in Jeju. 1. Most orange orchards are located on terrace and cindercone thus soil moisture and microclimate of an orchard will greatly be affected by its topography. 2. Excessive well drainage, shallow soil depth, high content of gravels, low solid phase ratio and strong wind will give severe problem of soil moisture and wind errosion, thus the exte- nsion of soil depth is necessary for maintain nutrients, water and sufficient root volume. 3. Available soil water was significantly and positively correlated with organic matter content and clay content also contributes to available soil water. Vinyl mulching was greatly helpful for soil water conservation, wind errosion prevention, soil temperature increases during winter. 4. Abundant amphoteric amorphous allophane take a key role to fix phosphorus and also rations and thus it is the major factor to determine fertilizer efficiency. Lime and phosphorus must be applied in deeper soil layer. Release of filed phosphorus must be reevluated for availability. 5. Organic matter such as see weeds will greatly increase fertilizer efficiency and low fertilizer efficiency during spring may be related to available soil water. 6. Nitrogen was in superoptimum and Mg was enough but P and Ca were somewhat deficient according to leaf analysies while K was deficient according to fruit analysis. Phosphorus application increased sugar/acid ratio and potassium decreases rind percentage. 7. Manganese deficiency and toxicity appeared in a few places. Iron and boron were enough. Most places showed tendency of copper excess but some places showed copper deficiency. 8. Soiling after elimination of rock base, application of slow release fertilizer and abundant organic matter, vinyl mulching and drip irrigation will increase fertilizer efficiency greatly and fruit yield drastically.