• Corrosion Science and Technology
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• v.21 no.2
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• pp.77-88
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• 2022

Schiff base quinazoline derivative viz., 3-((2-hydroxy-3-methoxybenzylidene)amino)-2-methylquinazolin-4(3H)-one (SB-Q), was synthesized in this study. Its corrosion protection impact on mild steel (MS) in 1 M hydrochloric acid solution was examined by performing weight loss measurements. The protective efficacy of SB-Q on MS in 1 M HCl was investigated based on its concentrations, immersion period, and immersion temperature. SB-Q was found to be an efficient inhibitor for the corrosion of MS. Its inhibition efficiency was improved by increasing the concentration of SB-Q to an optimal concentration of 500 ppm. Its inhibition efficacy was 96.3% at 303K. Experimental findings revealed that its inhibition efficiency was increased with increasing immersion time, but decreased with an increase in temperature. The adsorption of SB-Q molecules was followed the Langmuir adsorption isotherm model. The adsorption of the examined inhibitor molecules on the surface of mild steel was studied by density functional theory (DFT). DFT investigation confirmed weight loss findings.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.947-948
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• 2011

Efficiency of Multi D.O.F spherical motor is one of the important performance indicators. So Through the reduction of eddy current loss on how to improve the efficiency were studied. Stator iron core's material with high permeability and resistivity of material using the eddy current loss was reduced. However, it was the disadvantages of production and economic. For these reasons, prevent eddy current loss of the iron core of multi D.O.F spherical motor as a viable alternative to motor using rotor with double-air gap.

• Journal of Korean Institute of Industrial Engineers
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• v.31 no.2
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• pp.164-172
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• 2005

A loss function approach to a multiresponse problem is considered, when process parameters are regarded as random variables. The variation of each response may be amplified through so called propagation of error (POE), which is defined as the standard deviation of the transmitted variability in the response as a function of process parameters. The forms of POE for each response and for a pair of responses are proposed and they are reflected in our loss function approach to determine the optimal condition. The proposed method is illustrated using a polymer case. The result is compared with the case where parameter fluctuation is not considered.

• Transactions of the Korean hydrogen and new energy society
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• v.32 no.6
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• pp.477-482
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• 2021

Hydrogen production, hydrogen production cost, and utilization rate were calculated assuming four cases of hydrogen production system in combination of photovoltaic power generation (PV), water electrolysis system (WE), battery energy storage system (BESS), and power grid. In the case of using the PV and WE in direct connection, the smaller the capacity of the WE, the higher the capacity factor rate and the lower the hydrogen production cost. When PV and WE are directly connected, hydrogen production occurs intermittently according to time zones and seasons. In addition to the connection of PV and WE, if BESS and power grid connection are added, the capacity factor of WE can be 100%, and stable hydrogen production is possible. If BESS is additionally installed, hydrogen production cost increases due to increase in Capital Expenditures, and Operating Expenditure also increases slightly due to charging and discharging loss. Even in a hydrogen production system that connects PV and WE, linking with power grid is advantageous in terms of stable hydrogen production and improvement of capacity factor.

• Journal of Korean Society for Quality Management
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• v.26 no.4
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• pp.65-78
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• 1998

Process capability indices, used to determine whether a production process is capable of producing items within a specified tolerance, have been widely used in process assessments. In this paper, we consider some process capability indices using loss function when process is contaminated normal. Also, we examine some small sample properties related to these estimaters by some simulations.

• Bulletin of the Korean Chemical Society
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• v.17 no.9
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• pp.826-830
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• 1996

Fourier transform infrared (FTIR) temperature studies were performed to examine the microstructural changes that occur in annealing process of the thin films of 1,2-polybutadiene (1,2-PBu)/palladium chloride (PdCl2) complex. The disappearance of the infrared absorption intensities at 1640, 1418, 994 and 910 cm-1 signifies the consumption of 1,2-vinyl groups of 1,2-PBu. The progressive loss of unsaturation and production of methyl groups as a function of temperature were identified by the enhanced infrared absorption intensities at 1447 and 1375 cm-1. The loss of pendent carbon-carbon double bond is considered to involve both palladium-catalyzed addition reaction and thermally induced cyclization.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.4
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• pp.667-674
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• 1999

Intensive livestock production has increased dramatically in Europe since the 1960s, particularly. in Northern and Central European countries, resulting in large increases in the nutrient pollution of surface and ground waters and in atmospheric emissions of ammonia. This has arisen due to inadequate management of the large amounts manure produced, particularly where there has been insufficient land area used for efficient nutrient reuse in crop production. Nutrient pollution from intensive livestock production has progressively degraded the quality of water resources in many parts of Europe, with eutrophication of many inland and coastal waters, as well as soil acidification and ecosystem degradation. These problems have been known for many years, and although there are various international agreements on transboundary pollution, it is largely left to individual countries to set and enforce standards. Consequently, a number of different approaches are employed, although the common feature of these is to encourage farmers to use the nutrients in animal manures efficiently according to crop requirements, which also reduces the potential for accumulation in soil and subsequent loss to the environment. This paper reviews nutrient production and use in Europe and some of the strategies employed to avoid and reduce nutrient pollution.

• Journal of the Korean Operations Research and Management Science Society
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• v.26 no.4
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• pp.143-153
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• 2001

In this study we develop a computer simulation model to evaluate the effects of various production and order processing policies measured in terms of on-time delivery rate and average waiting time of job orders. Policies considered include : eliminating inflated due date, lot splitting, loss time reduction, attaining full flexibility in production lines, and selective order promising scheme. Actual order-production data from a chemical company were used in the simulation model. Based on the simulation results, we make several suggestions that can significantly reduce the production lead time and increase the on-time delivery rate.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.154-158
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• 1997

This paper proposes a new resource allocation system where overall performance can be improved using production smoothing method. In economic point of view, market price is determined by the market mechanism that is subject to the law of demand and supply. Similarly, agents determine whether to allocate tasks to machines by profit and loss or not. In existing resource allocation system, tasks are exclusively allocated to agents with better manufacturing conditions, because they are evaluated by the only currency. But in the proposed resource allocation system, agents are evaluated by not only a currency but also machine specifications. Hereby, the production smoothing is achieved and we expect to improve system performance In this study, we propose a resource allocation system with consideration of Production Smoothing.

• Journal of the Korea Safety Management & Science
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• v.6 no.3
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• pp.131-140
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• 2004

The company was focusing on production which was partial mission rather than acquiring the information of customer in intensive process industry. The company accepted loss which is from over-production, losing of opportunity. After changing to web environment, supply chain is more complicated and need of customer is more various. As a result the company hard works on controlling production rates, production quantities in production area and gathering exact information which is about available resource and available quantities. Cooperated demand planning have to get decreasing of inventory, improving of customer service in supply chain management. Specially demand planning that considers allocation of capacity is executed in Iron-Industry. Demand planning must be classified by customer, region and supply position level.