• Environmental Engineering Research
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• v.21 no.2
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• pp.132-139
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• 2016

In early 90s the worldwide awareness about the energy crisis and global warming had been increased and emission reduction (by improving energy efficiency), as well as increasing the capacity of clean and renewable energies, showed themselves as the most important steps towards the sustainable development approach. However, investigations on Iran's environmental situation show huge decline in recent decades and apparently there is no sense of urgency about these issues through the vision of Iranian politicians. In this article the idea of replacing the old gas turbines of Polkalleh natural gas compressor station - as one of the main compressor stations of Iran - with newer and more efficient gas turbines is evaluated, emphatically for reducing greenhouse gases emissions and their environmental costs and decreasing natural gas consumption as well. Clearly such idea is costly, but analyzing its economic impacts, huge declines in annual costs and greenhouse gases emissions can be seen as well. So an investment about $95 million can decrease 40% of Polkalleh compressor station annual costs, 25% of natural consumption and 30% of $CO_2$ and $NO_x$ emissions. Besides the simple payback period of this investment is about 2.5 years from the cut-expenses of annual costs.

• Journal of the Society of Naval Architects of Korea
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• v.42 no.1 s.139
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• pp.57-63
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• 2005

This paper introduces basic research of optimum routing assessment system as voyage support purpose which can obtain safe and efficient route. In view point of safety, the prediction of ship motion should be evaluated in the condition of rough weather This part includes general seakeeping estimation based on 3 dimensional panel method and parametric roil prediction. For increasing voyage efficiency, ETA(Estimated Time of Arrival) and fuel consumption should be calculated considering speed reduction and power increase due to wave effects based on added resistance calculation and ship performance characteristics. Basically, the weather forecast is assumed to be prepared previously to operate this system. The idea of these factors in this system will be helpful to escape from dangerous voyage situation by wave conditions and to make optimum route planning based on ETA and fuel consumption.

• Journal of the Korean Applied Science and Technology
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• v.11 no.2
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• pp.39-54
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• 1994

I am going to survey major topics relating to the title by analyzing the following statistical data. 1 : Global trend of production and import of oil and relating materials 2 : Global trend of major oil production 3 : Capacity of Japanese factory for oil production 4 : Situation of mechanical expression based on raw materials 5 : Change of production amounts of Oil products 6 : Oil production of each items 7 : Imported amounts of oil products 8 : Vegetable oil meals, production, import and global trend 9 : Production of mayonnaise, dressing and edible processing oils 10 : Intake of nutrients, supply of lipids, and consumption of oils 11 : Global production of oleochemicals 12 : Sales amount of oleochemicals 13 : Capacities of fatty acid and fatty alcohol factories 14 : Oleochemical production in 1995 15 : Oleochemical procuction in asia 16 : Production of surfactants for industrial use 17 : Sales amount of detergents and washing materials 18 : Production of soap and synthetic detergent in Japan 19 : Consumption of soap. detergent, and synthetic detergent 20: Relation beween synthetic detergent production and popularization 21 : Biodegradability of soft detergent

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.544-547
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• 2002

According to the rising of national economic level. domestic consumption of vegetables having high additive values is increased continuously due to increased consumption of meat in last decade. These vegetables are produced almost in this country and are limited to import from neighbor countries in due of high transportation expenses for storing in refrigerated container. It is very important to mechanize the harvest work, forming more than 30% for their production cost, in order to cultivate variable vegetables at the same time according to their harvesting seasons. In this state its former harvest methods, with using of human power or semi-automatic harvest, caused to increase their production cost due to high labor cost and low working efficiency. The former onion harvest being operated almost by semi-automatic plant distributer mechanism have many limit and troublesome for cultivation spaces, vinyle mulched ridge, gravel mixture in soil. Therefore, it is necessary to develope a fully automatic and self-running situation and overcome above handicaps, even in the farm covered with vinyle house or mulch sheets. This newly developed onion harvest can be applied to plant various young trees and will be able to export together with onion haying their competition in the worldwide market in which the culinary vegetable method or farm conditions is similar to our country.

• Journal of Welding and Joining
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• v.9 no.4
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• pp.50-59
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• 1991

Large steel water pipes in Korea are joined prevalently by bell end method and welded at inside as well as outside of the pipes with the length of leg which is same as or larger than the thickness of pipes. This results in an excessive consumption of material and labor compared with foreign counturies such as USA, so that in our recent situation of requiring a number of water pipes such consumption is very ineffective and an improvement in weld design of water pipes is urgently necessary. In this experimental study, the possibility of reducing the length of leg to 85% of the pipe thickness was investigated through observations of microstructure and cross section of weldments, the tensile test, and the impact test of the field and laboratory specimens. As the results of this study, it was revealed that water pipes which have the leg of fillet about 0.8xthickness show a good weldability, have a greater strength than the base metal and absorb the enough energy to be safe in the working condition of the pipes.

• Korean Journal of Agricultural Science
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• v.47 no.2
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• pp.283-290
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• 2020

In 2018, 647 thousand tons of eggs were produced and consumed. However, the issue of pesticides used for egg in 2017 made Korean consumers worry about the food safety of eggs, and the volume of egg consumption decreased. The Korean egg industry also has another problem due to an unclear and inefficient marketing structure at the farm level. This marketing situation of eggs at the farm level in Korea needs a large-scale restructuring of the market structure, including introducing an EPC (egg processing center). Especially, the introduction of an EPC has been discussed by government officers and specialists, but the social benefit of an EPC, which will be the driving point for approving an EPC, has not been measured yet. The purpose of this study was to measure the effect of introducing an EPC in Korea. Through an analysis using EDM (equilibrium displacement model), a few findings are presented. First, the introduction of an EPC may increase the transparency of price discovery and decrease the transaction cost. And thus, it results in a higher producer price, lower consumer price, and larger quantity at market equilibrium. Second, an EPC will improve the level of food safety of eggs, which can increase the satisfaction of domestic producers and consumers. Third, the introduction of an EPC may create new consumption of eggs. Based on these three effects, the new social benefits in monetary terms from the introduction of an EPC in Korea could be 23.9 - 35.2 billion won.

• Industrial Engineering and Management Systems
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• v.9 no.4
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• pp.294-302
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• 2010

There is a trend toward the world's manufacturing sites moving to East Asia. After manufacture, these products are transported to the advanced nations for their consumption demands. Among such advanced nations, the U.S.A. has the largest demand, and then Japan and European countries follow. It should be noted that the infrastructures of the Asian districts used for the production sites are rather limited, and the volume of products transported from these districts of Asia to the U.S.A is becoming tremendously large. This situation is causing very serious traffic problems. New products are required to be transported swiftly by air. Once the consumption and market demands are stable however, the products should be sent rather slowly, but in larger amounts. However, the airports of China are quite restricted in capacity, while the transportation volume is becoming large. As a result, transportation cost and the time required for transportation are increasing. Now, a third method is appearing. This is the so-called Sea and Air transportation. The cost and time in transit of this mode take mean positions between Air and Ocean services. At present there exists no well-thought-out strategy for how to allocate these three methods of transportation. This paper is an attempt to theoretically describe this mechanism and to discover the optimal way to allocate the three modes. For this purpose, several mathematical properties of value and cost of the products are defined, and on this basis a simulation of the transportation is established.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.27 no.4
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• pp.52-64
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• 2019

The purpose of this study is to analyze the impact of macroeconomic variables on air passenger demand and provide useful information to airport managers and policymakers. Therefore, using the quarterly macroeconomic indicators from 2002 to 2017, the relationship with air passenger demand was demonstrated by multiple regression analysis. In the previous studies, they used GDP, Korea Treasury Bond, KOSPI index, USD/KRW Exchange Rate, and WTI Crude Oil Price variables. In this study, we used the Coincident Composite Index, Employment Rate, Consumer Sentiment Index, and Private Consumption Rate used as additional variables. It has confirmed that if the consumption of research results expands or the economic environment is right, it will affect the increase in international passengers. In other words, it confirmed that the overall economic situation acts as the main factor determining air passenger demand. It confirmed that the economic environment at the past has a significant impact on air passenger demand.

• International journal of advanced smart convergence
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• v.11 no.2
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• pp.118-127
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• 2022

Barrage language is a new media language based on Internet video. It is a representative expression of the Internet environment regardless of its format and content. As a unique movie viewing characteristic provided by the barrage function, the timeliness of feedback, entertainment, and interactivity of the content are excellent. Characteristic. Barrage language itself is closely related not only to the value of linguistic research, but also to the spread of the Internet in the Internet environment. Based on the current situation of Chinese video sites, this thesis explores how Barrage is an organic cycle of culture and consumption in a specific platform and group, and analyzes its propagation methods and effects. By analyzing the characteristics of content production patterns unique to the barrage culture, implications and reference values for production activities of other cultures, the effect of popularization on viewers and the production and consumption of the 'barrage' culture of the industry is studied, and furthermore, the 'barrage' culture is It was designed to be a reference for the development of the platform, internet culture, and animation industry culture.

• Journal of Electrochemical Science and Technology
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• v.13 no.2
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• pp.261-268
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• 2022

In this study, electrochemical treatment of urban wastewater with electrical conductivity of 1000 μS cm^-1 and chemical oxygen demand of 250 mg L^-1 was investigated using the variables of initial pH value, current density and flow rate. Electrocoagulation was used, in which aluminum and stainless steel were selected, as the electrochemical treatment process. The electrocoagulation process was operated in continuous mode. The data obtained in experimental studies show that the best COD removal efficiency occurred in experiments where the initial pH value was 6. The increase in current density from 5 A to 15 A decreased the removal efficiency from 79 to 67%. The increase in flow rate under constant current density also reduced the efficiency of removal as expected. In experiments in which current density and flow rate were examined together, the increase in flow rate allowed the application of higher current densities. This situation led to considerable reductions in energy consumption values, even if the COD removal efficiency did not significantly increase. The high COD removal obtained with the use of high flow rate and high current density indicates that the electrocoagulation process can be used for high flow rate municipal wastewater treatment.