• Transactions of Materials Processing
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• v.32 no.5
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• pp.247-254
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• 2023

This study conducted the wear tests on bending punches coated with PVD CrN and examined the surface quality of the product formed by each punch in the forming of uncoated TRIP1180 sheets. The study quantitatively estimated the surface quality of the product by measuring the roughness and imaging the product surface. The correlation between the punch wear depth and the product surface roughness was quantitatively analyzed. The results showed that before failure occurs, the product roughness was comparable with that of the as-received, and the product surface was smooth without scratches and defects. However, after failure, the punch wear is caused by fretting wear mechanism, and a punch whose coating is not completely peeled plows the product surface, resulting in severe scratches with grooves and ridges on the product surface. Severe wear on the punch surface caused by fretting wear can rapidly degrade the product surface quality as it is directly affected by the punch surface condition, and the product surface quality accurately reflects the punch wear condition.

• Korean Journal of Materials Research
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• v.18 no.6
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• pp.313-317
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• 2008

[ $LaFeO_3$ ] powders were synthesized using a method involving solution combustion, and the surface properties of these powders were examined by x-ray photoelectron spectroscopy. As the amount of fuel increased during the synthesis, the $LaFeO_3$ powders became amorphous with a large plate-like shape. It was found that the O 1s spectra were composed of two types of photoelectrons by deconvolutioning the spectra. Photoelectrons with higher binding energy come from adsorbed oxygen ($O^-$) whereas those with lower energy come from lattice oxygen ($O^{2-}$). The ratio of adsorbed and lattice oxygen increased as the ratio of the fuel and nitrate (${\Phi}$) increased. The binding energy of both types of oxygen increased as ${\Phi}$ increased due to the formation of carbonates.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.3
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• pp.261-272
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• 2014

Home appliances go through a couple of packaging stages from the plant to consumers. The primary packaging, inner packaging for each part, happens for protection after products leave the plant. The secondary packaging happens in the unit of product, ensuring cushioning packaging to protect products from movement. The final tertiary packaging is for transportation and delivery. Each stage of product packaging, however, costs a lot of money because of disposable packaging materials used in each stage including vinyl, tapes, Styrofoam, and corrugated cardboards. Discarded packaging materials also cause environmental problems. In an effort to come up with a measure to solve those problems, this study proposed a plan to minimize logistics costs with semi-permanent packaging materials to replace disposable ones including Styrofoam, vinyl, and corrugated cardboards in the stages of inner packaging, cushioning packaging, product unit-based packaging, and transportation. The study also developed a model to cut down logistics costs by reducing various packaging stages including the primary, secondary, and tertiary stage only to the secondary one through module-type products instead of the transportation- and delivery-type ones, as well as demonstrated the excellence of the study through numerical analysis.

• Journal of Korean Society for Quality Management
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• v.16 no.1
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• pp.78-87
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• 1988

The purpose of this study is to develop the algorithm applicable to the integrated production inventory model under quantity discount. To achieve this purpose, the integrated production inventory model which unifies the inventory problem of raw materials and the finished product for a single product manufacturing system is considered. The product is manufactured in batches and the raw materials are obtained from outside suppliers but some of the raw materials are discounted according to the purchasing quantity. The intergrated production inventory problem considered in this study is formulated by the non-linear mixed integer programming model, and the optimal solution is obtained by using the algorithm developed by Goyal. Then, the algorithm developed by this study is applied to the quantity discount problem, and the optimal solution is revised by this results. The quantity discount algorithm of the integrated production inventory model developed by this study gives a systematic procedure to obtain the optimum policy to minimize the total cost in any case. The numerical example involving 20 raw materials and 5 raw materials among them are discounted according to the purchasing quantity is given to verify the mathematical model and the algorithm developed in this study.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.116-117
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• 2014

This study is to environmental safety assessment of ground solidification materials using industrial by-products. also, physical and chemical properties were investigated. as a result, compared to conventional cement the survival rates are capable, was judged to be possible utilizing of ECO-friendly ground solidification materials.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.13 no.1
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• pp.29-41
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• 2002

Controlling food materials, is getting more significant in hotel management nowadays as the selling of food beverage continue to rise. F&B managers have been required to have new management of the food materials by a fierce competition, an increase in cost, the shortened span of product life and customer's demand that is becoming more various and sophisticated since Korea was placed under the influence of IMF. I'm going to analyze the factors that cause waste and loss through a series of the process to purchase inspect, store food materials, make a product with that materials and sell the product in order to make more profits by making the circulation of the food materials easier and more efficiently. I studied how 3 chain hotels of A group purchase, store the food materials and control stock. I made up questionnaires about the circulation and control of food materials to 107 cooks in order to know what the cooks who are working at the hotel regard as a real problem and a practical solution. This research indicates that purchasing, producing and selling departments don't establish the mutual connection, a professional purchasing manager is strongly needed and there is difficulty in predicting the proper timing to supply. Also the research shows that A hotel group controls the food materials by analyzing the amount of consumption, stock, setting up the period of validity and uses slowly moving food materials in stock mainly by introducing the menu that aims at four seasons. As a result, the research suggests that we should introduce the concept of food producing factory, as it were, Central Kitchen that is based on the network among various kitchens to improve the flow of the food materials.

• Journal of the Korean Geotechnical Society
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• v.20 no.2
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• pp.97-105
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• 2004

The purpose of this study is to provide the ways of recycling of by-product limes as lightweight fill, backfill materials, and lightweight blocks by performing experimental study. New lightweight fill materials and blocks were devised by mixing by-product lime, weathered granite soil, small pieces of waste EPS, and Portland cement. Physical, geotechnical, and environmental properties of the lightweight mixed soils and blocks were analysed by laboratory experiments for mixed samples manufactured with various mixing ratios. KMS tests were also performed to evaluate the concentration variation of the chemical components of the light weight blocks leachates. It is expected that this study will contribute to resolving the problem of by-product lime disposal as well as to recycling the by-product limes as fill materials and blocks.

• Journal of the Korean institute of surface engineering
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• v.29 no.6
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• pp.728-734
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• 1996

To obtain the relation in the electrochemical reduction of $CO_2$ in aqueous $KHCO_3$ colution between an activity for the product and the nature of Cu electrode, the electrode surface was characterized by using two methods: X-ray photoelectron spectroscopy (XPS) and photoelectron emission (PE) measurement. Electrolyses were performed with Cu electrodes pretreated in several ways. The distribution of the products changed drastically with electrolysis time and the pretreatment method. The features in XPS spectra were closely connected with the product distribution. The oxide film at the electrode surface was gradually reduced to bare Cu metal with electrolysis time, resulting in a variation of the product distribution. PE was measured by verying the wavelength of incident light at several temperatures. The dependence of PE on the measurement temperature changed greatly before and after electrolysis.

• Transactions of Materials Processing
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• v.8 no.6
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• pp.563-568
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• 1999

The study has been performed for the relation between die and product in closed die upsetting by the experiment. The strain of die has been given by the simple experiment using the strain gauge located at the outer surface of die and the deformation history of die and product has been given by the experiment and Lame's formula. The inner pressure of die causes the deformation of die that affects the accuracy of dimension and shape of product. The product with accurate dimension and shape can be obtained by analysing elastic deformation of die during upsetting process. The deformation of die during metal forming process has been usually predicted by the experience of industrial engineers or finite element analysis. But it is difficult to predict the dimension of product at unloading and ejected states. The study has given useful result for the deformation history of die and product through the experiment and Lame's formula at closed die upsetting, and can be applied in the die design for product with accurate dimension.

• Transactions of Materials Processing
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• v.10 no.1
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• pp.75-79
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• 2001

The study has been performed for the relation between die and product during forward extrusion by the experiment. Stains of the die have been given by the simple experiment using the strain gauge located at the outer surface of the die. The history of the deformation of the die and the product has been given by the experiment and Lame's formula. The inner pressure of the die causes the deformation of die that affects the accuracy of dimension as well as shape of the product. The product with accurate dimension and shape can be obtained by analysing elastic deformation of the die during the process. The deformation of the die during metal forming process has been usually predicted by the experience of industrial engineer or finite element analysis. But it is difficult to predict the dimension of the product at unloading and ejected states. In the present study, useful results for the deformation history of the die and the product were obtained through the experiment and Lame's formula in forward extrusion which can be applied to the die design for the product with accurate dimension.