• Journal of Navigation and Port Research
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• v.43 no.6
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• pp.469-474
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• 2019

One of the world's major resources is crude oil, the most fundamental part of the industry. There is no place that does not use crude oil. Petroleum refining products and chemical production industrial products are produced through nearby petrochemical complexes and ports after importing crude oil. There would be a possible relationship among the petrochemical complexes and nearby regional ports working with liquid cargoes. To confirm these relations, Ulsan Port, Daesan Port, and Yeosu Gwangyang Port were selected for this study. A Vector Auto Regressive model using time series data was applied. A Unit Root Test was performed. The relationship was confirmed through the Granger and Toda Yamamoto Causality Test.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.633-637
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• 2001

Oil fly ash is known as one source of raw materials from which vanadium and nickel metals can be recovered. The current recovery process of valuable metals from oil fly ash is mainly the hydrormetallurgy one. Nevertheless, a great amount about 50~80%, of unburned carbon remains as byproduct after hydrormetallursy process. In Taiwan, if hydrormetallursy processes have proceeded, it can be estimated that the annual production of unburned carbon is 25 thousand tons. From the viewpoint of resource recycling, this study is a preliminary study and investigates in recovery of sub micron- graphitized carbon from unburned carbon by a designed process. The designed process included the following steps: 1.selecting a portion with +400mesh size from unburned carbon; 2.treating the selected in ultrasonic waves; 3.using a 400mesh sieve to obtain the product which is under 400mesh; 4.Removal ash from the product. In regard to treatment by ultrasonic waves in the designed process, treating time of ultrasonic waves is a simple and only variance in this study. The results indicate that the production yields increase with the treating time of ultrasonic waves; the production yield in specific conditions of this study can reach about 23%, in which ash content in product is about 2.5%. According to results of SEM, TEM and XRD, the products from the designed process are flakes in shape, several microns in size and graphitized carbon in carbon crystal phase. Except to graphitized carbon, there are a little carbon blacks, which are graphite 2H in carbon crystal phase in the products. Conclusively, the designed process is possibly applicable, by which comes to the recovery of micron- graphitized carbon.

• Journal of Agricultural Extension & Community Development
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• v.23 no.3
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• pp.285-293
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• 2016

The increase in demand for leisure time by the public and the vitalization of agricultural tourism resulting from the expansion of the five-day work week are expected to greatly contribute to the rural economy, but actual studies analyzing the ripple effect of the agricultural tourism industry are lacking. In order to analyze the economic ripple effect, tourism or agricultural tourism must become an independent sector in the inter-industry relations table's sector classification, but because it is not, the study uses a method of analysis which involves creating a satellite account. However, because agricultural tourism has a clear main agent in farms unlike general tourism which does not, there is one method in which provisions are made by farms or farm villages and another method in which outside products are used. The purpose of the present is to measure the economic ripple effect of agricultural tourism with a focus on 162 subclasses by applying positive data from the education sector input into agricultural tourism. Satellite accounts which considered intermediate input were created and applied to positive data, the analysis of which revealed agricultural tourism to account for 462 billion won, which is 0.01% of the total production amount of 3,503,480 billion won, while the production inducement coefficient was 3.2895 units when the final demand of agricultural tourism occurs. When the production inducement coefficient is at 3.2895 units, highest sector was agricultural tourism at 0.9968 units followed by restaurants and bars at 0.3325 units, roadt transportation services at 0.3183 units, lodging services at 0.1520 units, and petroleum products at 0.1290 units.

• Journal of Korea Port Economic Association
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• v.36 no.4
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• pp.1-16
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• 2020

Since Korea has excellent port infrastructure and competitive petrochemical complexes, there is plenty of potential for creating an oil hub in Northeast Asia. In particular, Ship-to-Ship (STS), which creates high added values, contributes greatly to the national economy. In this study, the liquid cargo volumes of chemical industrial products, refined petroleum products, and crude oil were analyzed at the national and regional (Busan, Ulsan, and Yeosu/Gwangyang) levels. Additionally, a Granger causality analysis was performed between imports, exports, and transshipments, in pairs. ADF, PP, and KPSS were analyzed for the unit root test. In addition, the VAR model and expanded VAR model suggested by Toda and Yamamoto were used for further analyses. Findings revealed a difference in Granger causality depending on the region or cargo type. These findings suggest that policies and incentive schemes for ports need to be differentiated according to the region and cargo types. In addition, the different patterns in the relationship between transshipments and import-export petrochemical cargoes should be considered.

• Journal of Electrical Engineering and Technology
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• v.12 no.2
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• pp.559-568
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• 2017

Harmonic/inter-harmonic detection and analysis is an important issue in power system signal processing. This paper proposes a fast algorithm based on matching pursuit (MP) sparse signal decomposition, which can be employed to extract the harmonic or inter-harmonic components of a distorted electric voltage/current signal. In the MP iterations, the method extracts harmonic/inter-harmonic components in order according to the spectrum peak. The Fast Fourier Transform (FFT) and nonlinear optimization techniques are used in the decomposition to realize fast and accurate estimation of the parameters. First, the frequency estimation value corresponding to the maxim spectrum peak in the present residual is obtained, and the phase corresponding to this frequency is searched in discrete sinusoids dictionary. Then the frequency and phase estimations are taken as initial values of the unknown parameters for Nelder-Mead to acquire the optimized parameters. Finally, the duration time of the disturbance is determined by comparing the inner products, and the amplitude is achieved according to the matching expression of the harmonic or inter-harmonic. Simulations and actual signal tests are performed to illustrate the effectiveness and feasibility of the proposed method.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.440-444
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• 2003

A new approach for ground water treatment combines a permeable Fe(0) barrier to breakdown higher chlorinated solvents like PCE and TCE with a down gradient aerobic biological treatment system to biotransform less chlorinated solvents, such as DCE and vinyl chloride (VC). The expected bacterial performance down gradient of an Fe(0) barrier was evaluated through laboratory batch experiments with a toluene-degrading mixed culture that cometabolically transforms cis-1,2-DCE and VC. The amount of cis-1,2-DCE (initially at 2,000 ppb) and VC (initially at 2,000 ppb) transformed was controlled by the initial toluene(20,000 ppb) concentration. VC was removed much more effectively than Cis-1,2-DCE, and a higher toluene concentration in comparison to the co-substrate concentrations was needed for complete co-substrate removal. Overall, the coupling of an Fe(0) barrier and subsequent biodegradation appears feasible for remediation of complex mixtures of chlorinated solvents and petroleum hydrocarbons in groundwater.

• Applied Chemistry for Engineering
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• v.27 no.1
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• pp.10-15
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• 2016

In this new energy economy era, the importance of renewable energy resource needs to be highly addressed, as the demand of energy dramatically increases and fossil fuel is being exhausted. Lignocellulosic biomass is considered as the sustainable and renewable feedstock to produce biochemicals and biofuels that are the alternative for petroleum derived products. Furfural is a natural precursor for the range of furan based chemicals and solvents such as methylfuran, tetrahydrofuran, methyltetrahydrofuran, ethyltetrahydrofuryl ether, ethyl levulinate, levulinic acid, and alkanes. Thus, furfural should be a renewable platform chemical for biochemicals and renewable biofuels. In this paper, the concept of biorefinery, furfural production and its applications are briefly reviewed.

• Journal of Microbiology and Biotechnology
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• v.27 no.1
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• pp.1-8
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• 2017

The production of high-value chemicals from natural resources as an alternative for petroleum-based products is currently expanding in parallel with biorefinery. The use of lignocellulosic biomass as raw material is promising to achieve economic and environmental sustainability. Filamentous fungi, particularly Aspergillus species, are already used industrially to produce organic acid as well as many enzymes. The production of lignocellulose-degrading enzymes opens the possibility for direct fungal fermentation towards organic acids such as itaconic acid (IA) and fumaric acid (FA). These acids have wide-range applications and potentially addressable markets as platform chemicals. However, current technologies for the production of these compounds are mostly based on submerged fermentation. This work showed the capacity of two Aspergillus species (A. terreus and A. oryzae) to yield both acids by solid-state fermentation and simultaneous saccharification and fermentation. FA was optimally produced at by A. oryzae in simultaneous saccharification and fermentation (0.54 mg/g wheat bran). The yield of 0.11 mg IA/g biomass by A. oryzae is the highest reported in the literature for simultaneous solid-state fermentation without sugar supplements.

• Journal of Environmental Science International
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• v.13 no.4
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• pp.349-357
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• 2004

Emergy is a measure of the processes required to produce something expressed in units of the same energy form. Emergy based indices can provide insights into the thermodynamic efficiency of the process, the quality of its output, and the interaction between the process and its surrounding environment. However, in an industrial system, the inputs are mostly nonrenewable, renewable energy source is nearly zero, ultimate purpose is pursuit of profits in economic activity. In study, we present two indices based on emergy - EEE(Ecological Economic Efficiency) and ERI(Environmental Responsibility Index). The EEE is taken into account real value of product in market economy. The ERI is shown to be a function of the net yield of the economy, its ‘load’ on the environment and ecological economic efficiency. Manufacturing industry of Korea produced the 30% of total GDP in 2001. We applied these indices to manufacturing industry for environmental management and further sustainable industry. As a results, the highest ERI is 0.34 in recycling industries, the lowest ERI is 0.01 in coke, refined petroleum products which is dominated by ELR. The higher ERI, the more friendly to environment. The suggested indices help us understand relative contributions of various alternatives in company's production and consumption activity, and provide a tool of decision-making for the rearrangement of future industries. Furthermore, they contribute to environmental friendly operation and consumption.

• Journal of the Korean Wood Science and Technology
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• v.42 no.5
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• pp.499-509
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• 2014

Wood filler is a porous and anisotropic material having different size, shape, and aspect ratio. The use of wood fillers such as wood particle, wood flour, and wood pulp in wood plastic composites (WPCs) are growing rapidly because these wood fillers give improved strength and stiffness to WPCs. However, the wood fillers have originally poor compatibility with plastic matrix affecting the mechanical properties of WPCs. Therefore, to improve compatibility between wood and plastic, numbers of physical and chemical treatments were investigated. While the various treatments led to improved performances in WPC industries using petroleum-based plastics, full biodegradation is still issues due to increased environmental concerns. Hence, bio-based plastics such as polylactide and polyhydroxybutyrate having biodegradable characteristics are being applied to WPCs, but relatively expensive prices of existing bio-based plastics prevent further uses. As conventional processing methods, extrusion, injection, and compression moldings have been used in WPC industries, but to apply WPCs to engineered or structural places, new processing methods should be developed. As one system, co-extrusion technique was introduced to WPCs and the co-extruded WPCs having core-shell structures make the extended applications of WPCs possible.