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

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
• /
• 2011.04a
• /
• pp.131-138
• /
• 2011

Currently, many forest residues have been generated by the National Forest Management Operation. Unfortunately, most of the forest residues are supposed to be used as raw materials for burning fuels like wood pellets. Even though the forest biomass must be effectively used for making high value-added products, they may be subject to disposable raw materials for wood pellets. Wood pellets are regarded as burning fuels with less contribution to the decrease in carbon gas emission, compared to raw materials for kraft pulps. In this study, we studied whether or not forest biomass mixed with various ages and, species could be used as raw materials for kraft pulps.

• Tribology and Lubricants
• /
• v.30 no.1
• /
• pp.52-58
• /
• 2014

Because food crops serve as the raw materials for biodiesel, the increasing use of biodiesel as an alternative fuel can lead to adverse effects such as food price inflation and may contribute to global starvation. To solve these problems, efforts are being made to explore various nonedible raw materials for producing biodiesel. Different raw materials impart different fuel characteristics to biodiesel. In this study, we synthesized pure fatty acid methyl ester (FAME), which is a biodiesel component, and then analyzed its fuel properties. The fuel properties of pure FAME would be useful in producing biodiesel from various new raw materials.

• Food Science and Industry
• /
• v.53 no.4
• /
• pp.366-373
• /
• 2020

Due to environmental changes such as diet and fine dust, the public has a growing interest in health. With the growing interest in health, consumption of health functional foods to prevent diseases has increased, and the health functional food market is also growing. However, most health functional foods rely on imported raw materials, and the development of health functional foods using domestic raw materials is urgently needed. Therefore, in this paper, provides information on functional raw materials for health functional foods that have been recognized by using domestic agricultural products in Rural Development Administration, and insists that R&D should be more active in order to increase more domestic raw materials in the health functional food market in the future.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.29 no.2 s.43
• /
• pp.233-250
• /
• 2003

We often use the KCID(Korean Cosmetic Ingredient Dictionary) and ICID(International Cosmetic Ingredient Dictionary) within cosmetics research and within their export and import. so far, we do not have a database of a cosmetics' raw materials. Because of this, we consume a lot of time to find the raw material data that is needed. This study constructs a cosmetics' raw material database and develops the program to retrieve it. We used a Linux machine as the equipment for this study and we used Apache web server, MySQL database server and PHP as the tools of this study. 11,817 kinds of raw materials data were registered as ICID, 866 kinds of raw materials data were registered as KCID and 28,008 kinds of raw materials data with registered trade name into the database. Also, The database was composed of the database of the association form. The database of the online form could ultimately reduce the task time as soon as it did its purpose. The product of this study can become a good basis of data to reconfigure. In the future, it can become a good database in relation with different databases.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.23 no.3
• /
• pp.97-100
• /
• 1997

These days, the raw materials that have the cell recovering effect are used commonly in cosmetics. In this study, six materials were rested for the characteristics of recovering effect both on vivo and in vitro. Tested raw materials were Soypol, 3-APPA, Apple extract, Polygonatum japonicum extract, Scutellarkd baicalensis extract, Aloe extract. Among these materials, Soypol and 3-APPA were synthesized and others were made by extraction at the Pacific R&D Center. Human forearm skin and cultured skin cell were damaged by sodium lauryl sulfare and then raw materials were applied for open treatment on SLS damaged human skin or cells. The recovering effects of raw materials in vivo were evaluated by measuring transepidermal water loss, skin hydration and erythema and in vitro effects of proliferationg cells were assessed by neutral red uptake assay. In the in vivo study, only the evaluation by TEWL showed correlation with the visual score. Our of six materials, 3-APPA had the most positive effect in both in vivo and in vitro studies and the correlation was r=0.8286 (p=0.042).

• Journal of Ceramic Processing Research
• /
• v.20 no.spc1
• /
• pp.109-112
• /
• 2019

γ-dicalcium silicate(γ-C2S) is known as a polymorphism of belite. Due to its high CO2 fixed capacity and the low CO2 emission production process, γ-C2S has attracted more and more attention of researchers. For the further development of application of γ-C2S in building construction industry. In this study, we aim to investigate the method for synthesizing high purity of γ-C2S. The influence of different raw materials and calcination temperatures on the purity of γ-C2S was also evaluated. Several Ca bearing materials were selected as the calcium source, the materials which' s main component is SiO2 were used as the silicon source. Raw materials were mixed and were calcined under different temperatures. The results reveal that the highest purity could be obtained using Ca(OH)2 and SiO2 powder as raw materials. And for the practical application, a relatively economic synthesis method using natural mineral materials- limestone and silica sand as raw materials was developed, by this method, the purity of the synthetic γ-C2S was 77.6%.

• Journal of Korean Society for Quality Management
• /
• v.46 no.3
• /
• pp.497-508
• /
• 2018

Purpose: The purpose of this study is to research the revision efficiency of the referenced specifications/standards for raw and subsidiary materials in the field of national defense. Methods: Firstly, it was carried out to investigate the all of the Korean military drawings and establish the database for specifications/standards referenced in the field of national defense. Secondly, it was reviewed the validity of referenced specifications/standards of raw and subsidiary materials. Finally, proposal documents were made for invalid referenced specifications/standards of raw and subsidiary materials in order to suggest alternative specifications/standards. Results: All of the specifications/standards referenced in the Korean military drawings were 11,924 kinds and raw and subsidiary specifications/standards were 2,711 kinds. The proposal documents for revision of invalid referenced specifications/standards were suggested and approved by the military procurement standardization committee of DAPA (Defense Acquisition Program Administration). Therefore, the revision process of 472 kinds of referenced specifications/standards and 160,177 papers of the Korean military drawings were finished. Conclusion: Based on the results of this investigation, it could be significantly reduce to administrative costs and efforts through revision of referenced specifications/standards instead of conventional engineering change.

• Resources Recycling
• /
• v.30 no.1
• /
• pp.53-59
• /
• 2021

Waste vinyl generated from household waste has been used as a solid refuse fuel (SRF) due to the presence of impurities such as soil, metal, and glass; however, the amount of SRF used has been decreasing owing to recent environmental problems, thereby necessitating the need for recycling. In this study, the mixed recycled raw material produced from household waste vinyl and polyethylene (PE) single recycled raw material produced from agricultural waste vinyl were examined. Raw material analysis revealed that waste vinyl was mainly composed of polyethylene, and approximately 2% of ash remained in the mixed recycled raw material, whereas no ash was found in the PE single recycled raw material. In addition, the analysis of tensile strength according to the mixing ratio of the two recycled raw materials revealed that the highest tensile strength was approximately 16 MPa under the heat treatment temperature of 200 ℃, compression pressure of 30 MPa, and a mixing ratio of 3:7 (mixed:PE single). In addition, the highest bending strength was approximately 39 MPa under the heat treatment temperature of 200 ℃, compression pressure of 30 MPa, and a mixing ratio of 3:7 (mixed:PE single). Therefore, the possibility of recycling waste vinyl was suggested by investigating the change in strength characteristics according to the mixing ratio of the recycled raw materials.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.37 no.3
• /
• pp.50-58
• /
• 2005

It is generally known that paper industry is the second largest industry in the use of process water, and also have the highest environmental impact load in the contaminant sources. Paper is produced from the mixtures composed of 1% fibrous raw materials and 99% water. The optimum use of process water effects on the quality properties of paper and the environmental impact load of waste water treatment. In this research, the kinds of fibrous raw material & additives used in the paperboard production line were investigated, and the quantification of environmental loads and the environmental effects of process water on COD potential were evaluated. The NBDCODs were also analyzed from process water by the method of waste water treatment in paper mill and applied for the optimum use of recycling water, and zero effluent process. In the fibrous raw materials, KOCC caused the highest COD potentials, and sack paper & UKP was comparatively low. The NBDCOD of KOCC largely reduced after biological treatment because of easily biodegradable properties, but AOCC contained non-biodegradable materials. In chemical additives, COD was high in turns of rosin>starch>deaeration agent>dye, NBDCOD greatly reduced in starch and deaeration agent. In the case of 2 kinds of paperboard product, the COD potentials was mainly high in starch, AOCC and KOCC.