• Resources Recycling
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• v.7 no.3
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• pp.17-26
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• 1998

A study on the recovery of silver and nitric acid in the liquid waste resulted from the mediated electrochemical oxidation(MEO) process was conducted. The removal of silver in the concentrated nitric acid solutions was carried out by the electrodeposition. The removal efficiency more than 98% could be obtained in nitric acid concentrations less than 3 M with the current efficiency of nearly 100%. The experimonts on the evaporation for the recovery of nitric acid were performed as well. At the evaporation factor of 25., the degree of nitric acid recovery in 3.5 M nitric acid solution containing 0.5 to 1.0 mol% NaNO, was 80~90% resulting in 2.8~3.1 M nitric acid. The design factors and operating conditions of the distillation tower were analyzed by using MEH model derived by Maphtali-Sandholm with the throughput of 4 kg/hr for the enrichment of dilute nitric acid solution recovered by evaporation to reuse in the MEO process. The distillation column composed of eleven theoretical stages having the overall tray efficiency of 70% are needed to obtain 1.03 kg/h of 12M nitric acid and 2.97 kg/h of water with feed being introduced to the column at tray 6 from the bottom at the reflux ratio of 0.25, the reboiler with the heat load of 2.7 kW, and the condenser with the cooling load of 0.5 kW.

• The Korean Journal of Archival Studies
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• no.53
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• pp.229-259
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• 2017

The purpose of this study is to find out the level of the classification system of the government-funded research institutes and to search the future direction of the classification scheme of these research institutes. As a result of analyzing the classification system and regulations of the 23 government-funded research institutes, it is found that the regulations of the records management of most institutions are basically based on other regulations before Public Records Act. In addition, there are not many institutions in which the record production system that reflects the Public Records Act is introduced, and the production and classification of the records are performed separately, and the classification scheme in which the organization classification and the functional classification are mixed is often used only as a reference tool for setting retention period. To overcome this situation, it is necessary to improve the regulation, classification scheme and system. The revision of the law at the national level and establishment of records management regulations at the institutional level should be made. A special classification scheme for 'research' which is a core function of the research institute should be designed and this classification scheme must be applied from the registration stage of records. The fact that the record management obligation is ignored and the production records are not properly managed is to deny the value of the research field records by themselves. I hope that the records management of government-funded research institutes will be moved in place as soon as possible and practical issues will be communicated to academia and good ideas for better development will be returned to the field of practice.

• Journal of the Korea Society of Computer and Information
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• v.27 no.10
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• pp.267-274
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• 2022

The purpose of this study is to investigate the learning satisfaction and perception of the students who have taken the online classes of the Digital Innovation Sharing University in the field of new energy industry, and to analyze the relationship between the learning satisfaction and core competencies. In order to achieve this purpose, the results of the learning satisfaction survey of a total of 470 students who took the digital innovation sharing university classes in the new energy industry were analyzed in both quantitative and qualitative methods. As a result of quantitative analysis, students' learning satisfaction was generally above average, and they were particularly satisfied with the setting and operation of educational goals. In addition, it was found that students' learning satisfaction had a statistically significant effect on students' core competencies. As a result of the qualitative analysis, it was possible to confirm the direction of improvement of the curriculum in the areas of function, operation, and content. Based on the results of this study, it is expected that the digital innovation sharing university curriculum quality management feedback system will be prepared in the future, and it will be the foundation for the continuous establishment of the curriculum quality management system.