• New & Renewable Energy
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• v.19 no.2
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• pp.13-22
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• 2023

With the increased interest in renewable energy, various hydrogen production technologies have been developed. Hydrogen production can be classified into green, blue, gray, and pink hydrogen depending on the production method; each method has different technical performance, costs, and CO₂ emission characteristics. Hence, selecting the technology priorities that meet the company strategy is essential to develop technologically and economically feasible projects and achieve the national carbon neutrality targets. In addition, in early development technologies, analyzing the technology investment priorities based on the company's strategy and establishing investment decisions such as budget and human resources allocation is important. This study proposes a method of selecting priorities for various hydrogen production technologies as a specific implementation plan to achieve the national carbon neutrality goal. In particular, we analyze key performance indicators for technology, economic feasibility, and environmental performance by various candidate technologies and suggest ways to score them. As a result of the analysis using the aforementioned method, the priority of steam methane reforming (SMR) technology combined with carbon capture & storage (CCS) was established to be high in terms of achieving the national carbon neutrality goal.

• Journal of Microbiology and Biotechnology
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• v.21 no.12
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• pp.1250-1256
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• 2011

In this study, Bacillus licheniformis cells were immobilized by entrapment in calcium alginate beads and were used for production of alkaline protease by repeated batch process. In order to increase the stability of the beads, the immobilization procedure was optimized by statistical full factorial method, by which three factors including alginate type, calcium chloride concentration, and agitation speed were studied. Optimization of the enzyme production medium, by the Taguchi method, was also studied. The obtained results showed that optimization of the cell immobilization procedure and medium constituents significantly enhanced the production of alkaline protease. In comparison with the free-cell culture in pre-optimized medium, about 7.3-fold higher productivity was resulted after optimization of the overall procedure. Repeated batch mode of operation, using optimized conditions, resulted in continuous production of the alkaline protease for 13 batches in 19 days.

• Proceedings of the Korea Society for Simulation Conference
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• 1999.04a
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• pp.47-52
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• 1999

In this paper we propose new approximate method for the performance analysis of closed-loop production system with unreliable machines and random processing times. The approximate method decomposes the production system consisting of K machines into a set of K subsystems, each subsystem consisting of two machines separated by a finite buffer. Then, each subsystem is analyzed by analyzing method n isolation. The population constraint of the closed-loop production system is taken into account by prescribing that the sum of average buffer level in the subsystems is equal to the number of customers in the closed-loop production system,. We establish a set of equations that characterizes unknown parameters of the servers in the subsystems. An iterative procedure is then used to determine the unknown parameters. Experimental results show that these methods provide a good estimation of the throughput.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.389-392
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• 2002

Local Mechanical work is researched which spending unnecessary labors and time due to unnecessary material accumulation and fabricated on site. Accordingly, this study analyzes the work process of mechanical equipments by Lean Production principles. Value Stream Analysis(VSA) uncovers waste factor of the existing method and manufactory production method using Value Stream Mapping(VSM). In the results, this study presents improvement of the existing method problems and negative factors of manufactory production.

• The Transactions of the Korean Institute of Power Electronics
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• v.8 no.4
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• pp.359-365
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• 2003

This paper describes the on-line readymixed concrete production system using CAN network, which is a leading industrial control network. The CAN network interface circuits for moisture sensor and load cell sensor we designed for CAN network of readymixed concrete production system, respectively, and also the method for networking 2-states devices such as limit switch and lamp is suggested. The operating status of a overall remicon production system is monitored, and also the system is controlled with host computer through the network. The CAN network interface method is applied to the real readymixed concrete production system to verify the performance of proposed method.

• Archives of design research
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• v.14 no.4
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• pp.157-165
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• 2001

The method to make ceramic pigments for 4 colour instead of ink in the process of the of set-printing and put them on the decal paper in the ceramic industry has been used to produce complicated images such as photographs or famous masterpieces. Offset-printing which is the production method for mass production, had enough worth to suffer the past high price of the production line. But today it is not suitable for the production method of small quantity and many kinds corresponding to needs for the various tastes and designs of consumers. Therefore I will put 4 colour printing method on the silkscreen, handiwork, suitable for the production method for small quantities and many variations to develop the methods that permit to cost effectively reproduce complex, high resolution, multicolor images. The study is expected to give value to ceramists who do various works and to be offered as the foundation in the field of design and expression.

• Resources Recycling
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• v.13 no.1
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• pp.59-67
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• 2004

A universal plasma-chemical module (PChM) for the industrial processing of different hydrocarbon raw material pyrolysis was designed and tested. Laboratory investigations for the plasma-chemical method of acetylene production from natural gas and different coals were made. Similar laboratory tests on the industrial production of acetylene as a raw material for organic syn-thesis were developed using the PChM. A comparison of the suggested plasma-chemical method with the traditional process of acetylene production were carried out. The outlook of the plasma-chemical method was shown.

• Journal of the Korean Professional Engineers Association
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• v.10 no.3
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• pp.17-26
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• 1977

In order to obtain the most practical and economically efficient method for refining of kenaf fiber and the production possibility of bag dproucts by using kenaf, Various chemicals and conditions of treatment for refining of kenaf bark were examined. Refining by the retting method was found much beneficial in quality of fiber and in processing cost than the chemical mettled. Bag products by using kenaf bark has good quality , and for practical use, Even if the production cost is slightly more expensive than jute bag, it could be reduced by planned mass production.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.6
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• pp.864-873
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• 2013

In developing countries, biogas energy production is seen as a technology that can provide clean energy in poor regions and reduce pollution caused by animal manure. Laboratories in these countries have little access to advanced gas measuring equipment, which may limit research aimed at improving local adapted biogas production. They may also be unable to produce valid estimates of an international standard that can be used for articles published in international peer-reviewed science journals. This study tested and validated methods for measuring total biogas and methane ($CH_4$) production using batch fermentation and for characterizing the biomass. The biochemical methane potential (BMP) ($CH_4$ NL $kg^{-1}$ VS) of pig manure, cow manure and cellulose determined with the Moller and VDI methods was not significantly different in this test (p>0.05). The biodegradability using a ratio of BMP and theoretical BMP (TBMP) was slightly higher using the Hansen method, but differences were not significant. Degradation rate assessed by methane formation rate showed wide variation within the batch method tested. The first-order kinetics constant k for the cumulative methane production curve was highest when two animal manures were fermented using the VDI 4630 method, indicating that this method was able to reach steady conditions in a shorter time, reducing fermentation duration. In precision tests, the repeatability of the relative standard deviation (RSDr) for all batch methods was very low (4.8 to 8.1%), while the reproducibility of the relative standard deviation (RSDR) varied widely, from 7.3 to 19.8%. In determination of biomethane concentration, the values obtained using the liquid replacement method (LRM) were comparable to those obtained using gas chromatography (GC). This indicates that the LRM method could be used to determine biomethane concentration in biogas in laboratories with limited access to GC.

• Transactions of the Korean hydrogen and new energy society
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• v.17 no.2
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• pp.218-226
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• 2006

It can be obtained from hydrocarbon and water, specially production of hydrogen from natural gas is most commercial and economical process among the hydrogen production methods, and has been used widely. However, conventional hydrogen production methods are dependent on fossil fuel such as natural gas and coal, and it may be faced with problems such as exhaustion of fossil fuels, production of greenhouse gas and increase of feedstock price. Thermochemical hydrogen production by nuclear energy has potential to efficiently produce large quantities of hydrogen without producing greenhouse gases. However, nuclear hydrogen must be economical comparing with conventional hydrogen production method. Therefore, hydrogen production cost was analyzed and estimated for nuclear hydrogen as well as conventional hydrogen production such as natural gas reforming and coal gasification in various range.