• Journal of Korean Society of Water and Wastewater
• /
• v.25 no.6
• /
• pp.885-892
• /
• 2011

In this study, LCA(Life Cycle Assessment) on 'Saemangum CSO Project' was carried out to evaluate environmental impact which occurred during the construction and operation periods and the potential environmental impact reduction was analyzed by comparing production and reduction level of pollution loads. LCA was conducted out according to the procedure of ISO14040 which suggested Goal and Scope Definition, Life Cycle Inventory Analysis, Life Cycle Impact Assessment and Interpretation. In the Goal and Scope Definition, the functional unit was 1 m3 of CSO, the system boundary was construction and operation phases, and the operation period was 20 years. For the data collection and inventory analysis, input energies and materials from civil, architecture, mechanical and electric fields are collected from design sheet but the landscape architecture field is excepted. LCIA(Life Cycle Impact Assessment) was performed following the procedure of Eco-Labelling Type III under 6 categories which were resource depletion, eutrophication, global warming, ozone-layer destruction, and photochemical oxide formation. In the result of LCA, 83.4% of environmental impact occurred in the construction phase and 16.6% in the operation phase. Especially 78% of environmental impact occurred in civil works. The Global warming category showed the highest contribution level in the environmental impact categories. For the analysis on potential environmental impact reduction, the reduction and increased of environmental impact which occurred on construction and operation phases were compared. In the case of considering only the operation phase, the result of the comparison showed that 78% of environmental impact is reduced. On the other hand, when considering both the construction and operation phases, 50% of environmental impact is increase. Therefore, this study showed that eco-friendly material and construction method should be used for reduction of environmental impact during life cycle, and it is strongly necessary to develop technology and skills to reduce environmental impact such as renewable energies.

• The Journal of the Korea Contents Association
• /
• v.20 no.12
• /
• pp.287-300
• /
• 2020

The present study applied the IPA(Importance-Performance Analysis) to derive several practical alternatives for the improvement of Chuncheon Silver Orchestra program using IPA(importance-performance analysis). Most importantly, this work performed a comparative study using sample data collected from two groups of silver member(N=53) and program operator(N=32). A careful literature review leaded to the development of six types of evaluation sectors, including 'connection with the local community', 'budget operation', 'program operation', 'manpower operation', 'public relations strategy' as well as 'environment for program operation'. This work further devised twenty-two evaluation items. The results indicated that silver member group rated 'manpower operation' the highest in their both perceived importance and performance. Program operator group rated 'budget operation' and 'manpower operation' rated the highest in their perceived importance and performance, respectively. The results form IPA matrix analysis provides an important implication that much efforts and interests should be sustainably given from the perspective of the silver member group and the program operator group coupled with four types of IPA quadrant, accordingly.

• Proceedings of the KSME Conference
• /
• 2000.04b
• /
• pp.199-204
• /
• 2000

A low temperature differential model stirling engine is manufactured, and its operation characteristics are measured and analyzed by SIMPLE analysis model, in which heat transfer processes are simply considered. The heat transfer coefficients between working fluid and heat sources in the analysis are estimated by comparing the P-V diagrams by experiment and by analysis. This result may be very useful for further design and manufacture of model Stilting engines as well as real engines because it provides a comparatively correct predictions of the operation conditions and power output. It will be also conveniently used as an educational material for mechanical engineering students because it can be a nice example of optimal design process to decide the phase angle and compression ratio of engine design with a simple but realistic simulation.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2006.05a
• /
• pp.381-385
• /
• 2006

This research introduces easy tool manufacturing method regarding tool manufacturing procedure. In the conventional method, wire cutting machining and lapping operation of corner and render region were performed after shrink-fitting to ensure the accuracy of gear profile. But lapping operation is very difficult due to corner and render is located deep inside of die. In this research, wire cutting operation was performed after $1^{st}$ ring was shrink-fitted to ease lapping operation and increase the accuracy of corner radius. Before $2^{nd}$ ring fitting, lapping was completed. Elastic deformation amount due to $2^{nd}$ ring fitting and cold forging was calculated through finite element analysis and wire cutting specification was offset in that amount. Comparison of gear dimension between analysis and forged part ensures the validity of new manufacturing methods.

• Proceedings of the KIPE Conference
• /
• 1998.10a
• /
• pp.636-641
• /
• 1998

In this paper, operation characteristics of the Zero-voltage-Switching(ZVS) mode and Non-Zero-Voltage-Switching (NZVS) mode of the active clamp (ACL) forward converter are compared through the loss analysis. The losses of semiconductor devices, transformer and passive elements of the converter are analyzed and compared for each type of operation mode. In order to verify the validity of the analysis, we have built a 50W ACL forward converter and measured the losses of the converter. From the experiment it is known that the ACL forward converter shows nearly same loss distribution for both of operation modes

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2013.05a
• /
• pp.173-175
• /
• 2013

In tall building construction, the equipment operation plans have an effect on productivity. Equipment, used in tall building construction, has operating plans of each it and restrictively operate owing to the first placed equipment operation. Therefore the interference of equipment was occur frequently. As it, the productivity is less effective and the construction delay occurs. This research was analysis the interference elements between the equipment for constructing the efficient equipment associated operational processes. The interference elements between the equipment derive through expert advice and analysis using IPA. Through the IPA, this research deducted the interference elements located 'Concentrate Here' which is the highest importance and the lowest performance.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.57 no.4
• /
• pp.383-387
• /
• 2008

This paper analyzes the operation characteristics of a self excited induction generator with Steinmetz connection. For this analysis, the symmetrical components analysis is used to obtain the related expressions and the excitation capacitance and the magnetizing reactance are determined in turn by the condition of self excitation which includes the input impedance of the generator as viewed across load terminals. Two simultaneous equations of the condition of self excitation itself are solved by using the real and imaginary function in an application software. This method is applied to simulate the operation characteristics when the generator is driven at rated speed and the specified excitation capacitor is connected across the lagging phase. The results show that better operation characteristics except generated frequency are obtained by using relatively large excitation capacitance and resistive load.

• Journal of Korea Port Economic Association
• /
• v.28 no.3
• /
• pp.151-165
• /
• 2012

This study is to develop a job model through job analysis on port security operation using a DACUM Method. Total 8 duties and 59 tasks are drawn through job analysis on port security operation. DACUM committee evaluated the degree of importance, difficulty and frequency of execution by each work with ABC rankings. In dosing so, job analysis model on port security operation by completing a DACUM research chart including job, duty and task in the field of port security operation is concluded. Such a Job model development could be used as a basic data and information for developing a short and long-run education programme in the field of port security operation.

• Journal of Korean Society of Water and Wastewater
• /
• v.34 no.6
• /
• pp.495-502
• /
• 2020

The 37 indicators for performance evaluation of public sewage management agencies are divided into four major categories (agency manpower management ability, wastewater treatment plant operation and management, sludge and water reuse, service quality) in the first stage, and the necessity and score acquisition for the detailed indicators by each major category in the second stages. Priority was investigated through the Analytic Hierarchy Process (AHP) analysis technique for ease and relevance of company efforts. Also, based on the results of this analysis, integrated type weighting and relative importance were analyzed. As a result of the analysis, the weight and relative importance of the first stage classification were in the order of wastewater treatment plant operation and maintenance, operation agency manpower management ability, sludge and water reuse, and service quality. As a result of analyzing the weights and priorities of the detailed performance indicators in the second stage, it was found that operator's career years, the percentage of certification holding rate in operators, compliance with the effluent water quality standards, training times for operators, and efforts to manage hazardous chemicals were important. Some of the indicators of operation agency performance evaluation may include indicators in which the performance of the company's efforts is underestimated or overestimated. In order to improve this, it is necessary to give weights in consideration of the necessity of the indicator, the relevance of the company's efforts, and the ease of obtaining scores.

• The Mathematical Education
• /
• v.59 no.2
• /
• pp.167-183
• /
• 2020

This study is an analysis study on the number and operation area of middle school mathematics curriculum. This study is a literature analysis study that analyzes the historical transition process of number and operation area, and suggests the restructuring direction of mathematics learning contents for numbers and operation areas based on the results. In order to achieve this research purpose, the contents of the number and operation areas suggested from the 1st middle school mathematics curriculum to the 2015 revised middle school mathematics curriculum were considered. In addition, in this study, analysis of the mathematical learning contents of number and operation area was conducted. The details of the study are as follows. First, it was decided as a tertiary mathematics curriculum as a criterion for analysis. Second, a basic analysis framework was developed by subdividing the content of mathematics learning into content elements and terminology elements. Third, on the basis of the developed analysis framework, mathematics learning contents that are the core issues of number and operation area were extracted. Fourth, the extracted mathematics learning contents were compared with foreign curriculum. Finally, based on the analysis results, the direction of restructuring for the number and operation area of middle school was suggested. The results of this study are expected to be the basis for the development of a new curriculum.