• Journal of the Korean Society of Clothing and Textiles
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• v.5 no.1
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• pp.23-26
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• 1981

In this paper, the extraction mechanism of free formaldehyde in the urea formaldehyde resin finished cotton fabric is discussed. An empirical equation for formaldehyde release has been formulated. $$F=3.7\times10^{-3}\;H\;T^{2.2326}+440$$ in which, F: the amount of free formaldehyde extracted ($\mu$g/g) H: extraction time (min) T: extraction temperature ($^{\circ}C$)

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.6
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• pp.606-614
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• 2017

Amount of food waste has been increased annually in Korea and re-use of food waste as a fertilizer or soil amendment in agricultural field has been studied. Therefore, main purpose of this research was to determine optimum condition of hydrolysis for food waste management. Three different solvents, HCl, $H_2SO_4$, and KOH, were used and varied concentration at the range of 10~30% and hydrolysis time at the range of 1~3 hours were evaluated. In general, reduction rate of food waste was increased when concentration of solvent and hydrolysis time was increased except when KOH was used. Among different solvents, concentration, and hydrolysis time, the highest reduction rate (97.79%) was observed when 30% of HCl was used with temperature of $140^{\circ}C$ at 2 hours of hydrolysis time. In addition, neutralization effect of alkalic materials, shell waste (SW) and egg shell (ES) was evaluated. Both SW and ES increased pH of finished acid hydrolysis solution up to 7.61 indicating that neutralization effect of SW and ES was sufficient for finished acid hydrolysis solution. Contents of organic matter was also at the range of 10.7~13.04% and 5.53~8.04% respectively when HCl and $H_2SO_4$ were used as solvent. Overall, hydrolysis technique can be used to manage food waste with selected optimum condition in this study and characteristics of finished hydrolysis solution after neutralization might be suitable for soil amendments.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1995.04a
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• pp.476-486
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• 1995

In this paper, an attempt has been made to revise Raafat' s(1985) results on an inventory model for decaying raw materials and the finished product at a constant rate which was based on Goyal's integrated inventory model for a single product system. This paper is concerned with scheduling the frequencies of order quantity of several different raw materials on a production inventory model. The purpose of this paper is to present a simple method of deciding the frequencies of order quantity of raw materials, in the sense of minimizing the average total cost of the system. We describe on iterative procedure for directly determining near optimal frequencies of order quantity for the raw materials and the associated fundamental cycle time which can be used for constructing the production duration of the finished product. In cases where feasible schedules cannot be constructed using the values from the iterative procedure, the procedure provides a basis for changing the order quantity frequencies and the fundamental cycle time to obtain feasible schedules. An example is given to illustrate the derived results.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.26 no.3
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• pp.50-57
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• 2003

In this paper, we consider an integrated inventory system where a single supplier purchases and processes raw materials in order to deliver finished goods to a single buyer for effective implementation of Just-In-Time purchasing. An integrated JIT lot-splitting model of facilitating multiple shipments in small lots is developed in a JIT purchasing environment. Also, an iterative solution procedure is developed to find the order quantity for the finished goods and raw materials, and the number of shipments between buyer and supplier. We show by example that the integrated policy adopted by both buyer and supplier in a cooperative manner can provide them a greater economic benefit than seeking the local optimal inventory policy independently.

• Journal of the Korean Society of Clothing and Textiles
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• v.10 no.2
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• pp.59-67
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• 1986

To control the amounts of formaldehyde released from the cotton fabric finished with N-methylol compounds, glycerol was used as a formaldehyde-scavenging agent. It was observed the effects of catalysts and curing conditions when aftertreated with glycerol on melamine resin finished fabric. The effects of Different processes of glycerol treatment, and different resins, urea resin and melamine resin, were compared. The conclusions obtained from the results are as follows: 1) It was shown hatt the aftertreatment with glycerol (treated without catalyst) was more effective than treated with catalysts in controlling free formaldehyde. 2) The optimum curing temperature and curing time for the glycerol aftertreatment without adversely affecting the other properties of fabric was about $160^{\circ}C$, 3 min. 3) According to the increase of glycerol concentration in both aftertreatment and simultaneous treatment the amounts of free formaldehyde was reduced. The rate of decrease was manifest within the limits of $6\%$ in the case of simultaneous treatment with glycerol ana resins, and $3\%$ in the case of glycerol aftertreatment on resin finished fabrics. 4) Dry wrinkle recovery angle was decreased the increase of glycerol concentration. Melamine resin had a little adverse effect than urea resin, particulary glycerol aftertreatment. 5) The breaking strength was increased with the increase of glycerol concentration.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.2
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• pp.460-474
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• 1997

The purpose of this study was to evaluate and compare the effectiveness of various low-viscosity resin systems used as rebonding agents to prevent microleakage at the margins of class I composite resin restorations. Seventy sound human premolars were selected for experiment. Class I cavities were prepared and each cavity was conditioned with a 37% phosphoric acid for 15 sec, rinsed with water for 15 sec, and dried with compressed air. Bonding agent(Scotchbond Multipurpose, 3M Co.) was applied and a hybrid composite resin (Z-100, 3M Co.) was placed using an incremental technic. The excess cured composite resin was carefully removed with Sof-Lex discs(3M Co.) to expose the original margins of the cavity. The following seven groups were established : group 1 was not rebonded and used as control group ; group 2 was rebonded with a Scotchbond Multipurpose(3M Co.) and finished ; group 3 was rebonded with a Fortify(BISCO) and finished ; group 4 was rebonded with a Concise white sealant(3M Co.) and finished ; group 5 was rebonded with a Concise white sealant(3M Co.) and not finished ; group 6 was rebonded with a P&F sealant(BISCO) and finished; group 7 was rebonded with a P&F sealant(BISCO) and not finished. The specimens were then subjected to 500 thermocycles between 5 & 65 with a 10 see dwell time and immersed in 2% methylene blue dye solution for 24 hours and sectioned with low-speed diamond cutter into two part under water condition. The extent of microleakage at rebonded margins was evaluated microscopically and scored for dye penetration according to the following scale : 0=no dye penetration ; 1=dye penetration to half-way along axial wall between enamel surface and DEJ ; 2=dye penetration beyond halfway along axial wall between enamel surface and DEJ ; 3=dye penetration to the full depth of DEJ or beyond DEJ. Selected samples were prepared for SEM observation to determine the depth of penetration of the rebonding agent into the marginal interface. The obtained results were as follows: 1. In the group 2 and 3, which is rebonded with a Scotchbond Multipupose and Fortify, dye penetration score were decreased significantly than that of group 1 (P<0.05), but group 4 and 6 were not statistically different from group 1(P>0.05). 2. There were significant differences between group 4, 6 and group 5, 7 when compared by dye penetration score (P<0.05). 3. In the SEM observation, Scotchbond Multipurpose and Fortify were penetrated within $30-40{\mu}m$ depth of the outermost surface. However, both sealants were failed to penetrate into the debonded interface.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1986.04a
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• pp.125-129
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• 1986

DDS network was implemented by utilizing the digital transmission in PSIN and finished field trial successfully for the first time in our country by DTC. Concept of DOS, how to implement, detail description of each section, comparison of DOS vs, analog data transmission system and result of field trial are presented.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.838-841
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• 2000

To improve the accuracy of products and improve the product quality, we need to enhance the machining accuracy of the machine tools. To this point of view, measurement and inspection of finished part as well as error analysis of machine tools has been studied for last several decades. OMM(On the Machine Measurement) has been issued to alternate with CMM, pointing out disadvantages of high expenses and lots of setting time in CMM. In this paper, we study 1) the spherical surface manufacturing by volumetric error compensation of machine tool, 2) the system development of OMM without detaching work piece from a bed of machine tool after working. 3) the generation of the finished part profile by On the machine measurement. Furthermore, the output of OMM is compared with that of CMM, and verified the feasibility of the measurement system.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.3
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• pp.1071-1090
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• 2016

Most of scheduling methods in the Grid only consider one special attribute of the resource or one aspect of QoS (Quality of Service) of the job. In this paper, we focus on the problem that how to consider two aspects simultaneously. Based on the requirements of the jobs and the attributes of the resources, jobs are categorized into three kinds: CPU-overload, memory-overload, and bandwidth-overload jobs. One job may belong to different kinds according to different attributes. We schedule the jobs in different categories in different orders, and then propose a scheduling method-MTS (multiple attributes scheduling method) to schedule Grid resources. Based on the comparisons between our method, Min-min, ASJS (Adaptive Scoring Job Scheduling), and MRS (Multi-dimensional Scheduling) show: (1) MTS reduces the execution time more than 15% to other methods, (2) MTS improves the number of the finished jobs before the deadlines of the jobs, and (3) MTS enhances the file size of transmitted files (input files and output files) and improves the number of the instructions of the finished jobs.

• Magazine of the Korean Society of Agricultural Engineers
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• v.40 no.5
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• pp.100-108
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• 1998

Compost stability represents the state of microbiological activity and measurements of respiration either through $CO_2$ evolution or $O_2$ uptake should provide the best indication of this state. Hog manure amended with sawdust was composted in a pilot-scale reactor vessels using continuous and intermittent aeration for 3 weeks. In this study we evaluated the $CO_2$ respiration rate effect of aeration method on the reduction of $CO_2$ evolution, and investigated the stability of fresh and finished compost for plant growth. The intermittently aerated composting is a practical proposition for a very stable compost making. The $CO_2$ respiration rate in the fresh and finished compost during intermittently aerated composting was maintained from 0.3 to 1.4 and was good for use in horticulture, while the continuously aerated composting was 7 to 23 and needed more time for compost curing.