• Membrane and Water Treatment
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• v.11 no.5
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• pp.363-374
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• 2020

Membrane distillation (MD) is a process used for water desalination. However, its commercialization is still hindered by its increased specific cost of production. In this work, several process configurations comprising Direct Contact and Permeate Gap distillation membrane units (PGMD/DCMD) were investigated to maximize the production rate and consequently reduce the specific water cost. The analysis was based on a cost model and an experimentally validated MD model. It was revealed that the best achievable water cost was approximately 5.1 $/㎥ with a production rate of 8000 ㎥/y. This cost can be further decreased to approximately 2 $/㎥ only if the heating and cooling energies are free of cost. Therefore, it is necessary to decrease the MD capital investment to produce pure water at economical prices.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.3
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• pp.479-482
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• 2002

Jookrhyuk (Bambusae Caulis in Liqamen) is one of the most important ingredients for treating Diabetes mellitus. Various aspects of quality of Jookrhyuk produced in Korea depending on carbonization process were compared. The pH Value was the highest in Jinyoungsangsa Jookrhyuk(pH 3.17) among the three different Jookrhyuk samples. Damyangsan Jookrhyuk that contains high level of total sugars(8.0 Brix, %) show incresed level of tar contents, it exhibited positive realationship between total sugar and tar contents. Concentration of methanol and phenolic compounds which are related to toxicity were the highest in Damyangsan Jookrhyuk(1.34㎎/㎖, 3.84㎎/㎖ respectively). The harmful heavy elements were not found in the evaluated Jookrhyuk samples. In coclusion, it was suggested that Bambusae Caulis in Liqamen should be further puryfied for using as main oral medicines for treating Diabetes mellitus.

• Journal of Microbiology and Biotechnology
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• v.6 no.6
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• pp.482-486
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• 1996

Batch fermentations of lactic acid were performed with Lactobacillus casei to investigate the effect of pH on cell growth and production of lactic acid and by-products. Maximum productivity of lactic acid increased with increasing pH from 5.0 to 6.5, and the extent of D-lactate production was different at each pH. Acetate and D-lactate concentrations increased even after the complete consumption of glucose in the medium. While a pH range of 6.0-6.5 was optimal for cell growth and lactic acid production, superior results were achieved at pH 6.0 when both maximum lactic acid productivity and minimum by-product formation were considered.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.51
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• pp.221-230
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• 1999

Many enterprises are performing the production planning computerization for survival in unlimited competing period. But it is very difficult to directly apply many production planning softwares to the domain-specific areas of many small enterprises because one enterprise is different from the others with respect to product type, production process, and order fulfillment method. Practically most small enterprises depend on experienced production managers in production planning, so then many problems such as overtime work and cost have been appeared. The purpose of this study is to develop production planning module for order-made production system in order to reduce overtime works and surplus costs. We developed production planning module with RDBMS, which is fit for small manufacturing company. Developing this software, we use Visual Basic 5.0 to provide GUI environment for the production planning module and Microsoft Access 97 is used to construct Database. This production planning module is applied to enhancement of productivity in M manufacturing company located in Asan.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.6
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• pp.76-81
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• 2019

In the mold-manufacturing field, various methods of advanced production technology are being used in the production of industrial-grade gear pulleys. Among the current methods are injection molding, hoop molding, insight molding, two-material molding, compound-mold molding, as well as engineering plastic mold. Currently, casting pulleys are inexpensive because they are produced in small quantities. However, they produce complications during the manufacturing process, are very unreasonable for mass production, and are disadvantageous in cost competitiveness. Pulleys are divided into hundreds of kinds and thousands of kinds, so the production methods vary. As these pulleys are made of a single material by a casting and welding method, they are not manufactured using injection molds consisting of different materials. In this research, pulleys, shafts, and reinforced plastic materials were incorporated using ANSYS software, and a low-cost, lightweight technology was applied for trial production with optimum design and extrusion technology.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.411-414
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• 2015

The purpose of this study is to conduct a comparative analysis between Korea and the United States of the supply process of unit modular housing at both the factory production phase and the transportation and lifting phase, as part of an attempt to invigorate the unit modular housing market in Korea. Unlike the practice in the United States, one of Korea's unique characteristics is that the floor is constructed with reinforced concrete and hot water heating system. To do this, the wet method in Korea is used that includes concrete placement, curing and constructing hot water floor heating system at the factory production phase, which results in a longer production time and also requires the lifting of heavier loads. In the United States, interior and exterior finishing works of modular housing are performed by different companies, and the distance between the unit module factory and the construction site is quite far. This kind of dualized production structure may cause confusion when it comes to schedule management, procurement management, and stock management. Moreover, problems caused by external environmental factors such as wind and rainfall were reported in the course of long-distance transportation. The results of this case comparison are expected to provide fundamental data that will reduce the amount of trial and error in the unit module production, transportation and lifting work in Korea, which has a comparatively small number of unit modular housing cases.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.57-58
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• 2000

Production of dye-decolorizing enzyme was investigated with the cultivation of Geotrichum candidum Dec1 (abbreviated to Dec1) using molasses as a cheap raw materials. Molasses was found to stimulate the enzyme production as well as a role of carbon source, because the production increased with molasses content up to 50 g/L. However, the severe inhibition of dye-decolorizing enzyme activity was observed even at low concentration of molasses 10 g/L when purified decolorizing peroxidase was used. Its inhibitory effect was reduced through the cultivation of Dec1. The fractions of molasses separated by a gel chromatography showed the different degrees of inhibition. As a way to reduce the inhibitory effect, the dilution of culture broth was examined, and the total decolorizing activity for Reactive blue 5 increased 7 times as much as that of original culture broth by 30 times dilution. On the basis of result, we proposed a process scheme which can fully utilize both positive and negative effect of molasses in dye-decolorizing process using molasses.

• Journal of the Korea Institute of Building Construction
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• v.2 no.2
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• pp.157-164
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• 2002

In this study, attempts to analyze the case study of production design were carried out through: 1) exploration of the factors influencing the interface between architectural and production design phases; 2)application of precast technologies. Building design and construction planning in Japan may be characterized by ample use of Production Design which extends over the whole projects phases. Taking a composite construction system for apartment buildings which allow for alternative combination of different technologies as a case study object, three projects have been chosen to analyze actual process of determining product sub-system and their specification. And the expectancies of this paper are that it can be used as efficient data for improvement of system to systematize Constructability(Buildability) in korea.

• Journal of Technology Innovation
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• v.6 no.1
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• pp.187-214
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• 1998

This paper tries to examine the effectiveness of inventory reduction to the productivity increase and the impact of production environments on its effectiveness utilizing the Profit Impact of Market Strategy (PIMS) Database from the Strategic Planning Institute, a large data set that covers a variety of manufacturing activities from the early 1970s to late 1980s. The empirical results of this paper support the robustness of the principle of "Lean Production" or JIT system (also referred to as "Stockless Production"). We also find that the overall environment in which manufacturing strategic business units operate is an important factor in determining the different degrees of effectiveness of the work-in process (and raw materials) invertory reductions. In particular, we find that the effectiveness of the work-in process reduction varies according to the position in the product life cycly as well as the complexity and characteristics of the production processes.roduction processes.

• Journal of Microbiology and Biotechnology
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• v.20 no.8
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• pp.1251-1258
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• 2010

During the nitrogen-fixing process, ammonia ($NH_3$) is incorporated into glutamate to yield glutamine and is generally not secreted. However, in this study, $NH_3$-excreting strains of nitrogen-fixing Paenibacillus were isolated from soil. The ammonium production by the Paenibacillus strains was assayed in different experiments (dry biomass, wet biomass, cell-free extract, and cell-free extract adsorbed on nano $TiO_2$ particles) inside an innovative bioreactor containing capsules of $N_2$ and $H_2$. In addition, the effects of different $N_2$ and $H_2$ treatments on the formation of $NH_3$ were assayed. The results showed that the dry biomass of the strains produced the most $NH_3$. The dry biomass of the Paenibacillus strain E produced the most $NH_3$ at 1.50, 0.34, and 0.27 ${\mu}M$ $NH_3$/mg biomass/h in the presence of $N_2$ + $H_2$, $N_2$, and $H_2$, respectively, indicating that a combined effluent of $N_2$ and $H_2$ was vital for $NH_3$ production. Notwithstanding, a cell-free extract (CFE) adsorbed on nano $TiO_2$ particles produced the most $NH_3$ and preserved the enzyme activities for a longer period of time, where the $NH_3$ production was 2.45 ${\mu}M$/mg CFE/h over 17 h. Therefore, the present study provides a new, simple, and inexpensive method of $NH_3$ production.