• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.308-315
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• 1996

The utilization of high flowing concrete in construction sites is a world wide trend, and it will be increase to need for high flowing concrete in our construction sites. While it is quite easy to make high-flowing concrete in the laboratory, controlling slump in the field long enough to ensure easy placement once the concrete arrives at job site can be difficult. This study is the experimental study on the high-flowing and engineering properties of high flowing concrete using river sand and crushed stone according to the replacement percentage of fly-ash. As a results of this study is the mix proportion of replacement percentage of fly-ash 30% better than the others. And it is confirm to possibility of manufacture of the high flowing concrete.

• Journal of the Korea Institute of Building Construction
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• v.8 no.3
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• pp.111-117
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• 2008

This study provides the setting time prediction method of super retarding concrete incorporating mineral admixtures at the same time including fly ash(FA), blast furnace slag(BS) based on maturity method. The setting time was retarded, as super retarding agent contents increase and curing temperature decreases. In addition, apparent activation energy by Arrhenius function was ranged from $24{\sim}35KJ/mol$ with slightly difference along with mixture proportion. This value is smaller than existing value $30{\sim}50KJ/mol$. It is Indicated that equivalent age using setting time can be a proper method to predict setting time and it also exhibited comparable relativity between prediction value and measurement value. Therefore, this study provided setting time prediction value with super retarding agent contents and mineral admixture combination. Setting time prediction equation provided herein is possibly valid for estimating precise setting time of the super retarding concrete at the job site.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.100-101
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• 2018

Environmental problems caused by air pollution have been considered as serious critical issues in global perspectives. Controlling greenhouse gases has become one of the major environmental problems in construction fields as well. However, similar studies were mainly focused on suggestion of various methodologies for measuring CO₂ emissions of construction equipment and calculating emissions. This study aims to analyze the correlation between the CO₂ emissions and RPMs of equipment by the construction process based on row data collected from construction equipment actually operated in job sites. This study allows site personnels to determine the amount of emitted CO₂ under particular construction equipment under specific conditions during the targeted construction operations. The research findings expect to be used as fundamental informations for establishing environment-friendly construction operation planning.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.200-201
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• 2015

As manpower shortage of national construction site is continuing, a manpower of foreign laborers are steadily increasing. The construction industry impacts the purpose for productivity of laborers as labor-intensive industry against different industry. Therefore, there is a need of analysis of foreign laborer's productivity. This study analyzes to use foreign labor's psychological productivity factors as a basic standard by comparing to Korean's. Construction foreign laborers seem to put bigger priority on "accomplishment of task," and "job satisfaction," than Korean workers, according to the response results in Likert 5-point Scale Measurement with 11 kinds of psychological causes in theories regarding productivity factors. Thus, this study expects to use as baseline data for productivity management of construction foreign laborers.

• Journal of Digital Convergence
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• v.5 no.1
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• pp.141-157
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• 2007

Due to the development of Internet and networking technologies, it is much more easier to get in touch with public service through the web services such as tax, travel information, getting a job, etc. In order to measure the quality of official government web sites, we are to test the difference between the web quality of the government sites and the offline feature of the same official service by means of customer perspectives. The resulting of this study show that the quality of official web site has been improved so far though such areas as privacy, security needed to be updated. Especially the web interface or contact point of the digital media should be reflected customer's need so that the online materials may be quickly updated according to the request of client's.

• Solar Energy
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• v.20 no.3
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• pp.85-95
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• 2000

As the industry has been growing rapidly, the problem of environmental pollution has been on the rise seriously. In this paper, we used solar cells at the power supply unit of the equipment, which has been sold at present, for measuring the quality of water in order to complement the problem. Also, to get rid of the inconvenience that the examiners must go the job site, check and collect the polluted water we set the goal at designing the water pollution alarm system which measures the quality of water automatically using one-chip microprocessor and materializing the program.

• Journal of the Korea Institute of Building Construction
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• v.8 no.5
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• pp.119-125
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• 2008

In this paper, the estimation of super retarding concrete incorporating mineral admixtures at the same time including fly ash(FA), blast furnace slag(BS) are studied based on maturity method. The setting time was retarded, as super retarding agent contents increase and curing temperature decreases. In addition, apparent activation energy by Arrhenius function was ranged from $24\sim35$ KJ/mol with slightly difference along with mixture proportion. This value is smaller than existing value $30\sim50$ KJ/mol. Based on strength development estimation. it exhibited comparable relativity between prediction value and measurement value. Therefore, this study provided effective strength development prediction value with super retarding agent contents and mineral admixture combination. Strength development prediction equation provided herein is possibly valid for estimating accurate strength development of the super retarding concrete at the job site.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.13-14
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• 2013

Mechanical splices has been applied in nuclear power plant according to ASME(American Society of Mechanical Engineering) and ACI(American Concrete Institute) Code requirements. In particular sleeve with ferrous filler metal splices and cold roll formed parallel threaded splices have been used in domestic nuclear power plants. The objective of this study is to find out the constructability of the mechanical splices which had been used in Korea nuclear job site and to review the technical trends in the near future.

• The Korean Journal of Emergency Medical Services
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• v.21 no.1
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• pp.59-73
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• 2017

Purpose: This study aimed to enhance the efficiency of clinical training education by understanding paramedic students' perceptions of their hospital clinical training experiences. Methods: The subjects were 31 third paramedic students who participated in a population survey from June 25 to August 13, 2016. A Q card and Q sample distribution chart were created, and the P sample was selected by Q classification. The collected data were analyzed by factorial analysis using PC QUANL. Results: Four different perceptions were identified from the survey, which explained 44.1% of the variables. The four types were classified as Self-improvement-oriented (Type 1), Training-site avoidant (Type 2), Confidence acquiring (Type 3), and Over-willed (Type 4). Conclusion: Paramedic instructors and clinical training managers may want to consider these four perception types when planning clinical training and education programs to improve job performance.

• Journal of the Korean Society of Safety
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• v.20 no.4 s.72
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• pp.87-96
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• 2005

In the construction industry, most safety related researches have been focused on the safety matters in construction job site while the safety issues regarding facility management have been received limited attention. Hence, this research aimed to uncover the problems of current safety management practices then suggest improvement plans. Through the questionnaire suey and analysis, following conclusions were drawn. Regarding the safety mindset, participation rate in safety prevention activities is average at most. Therefore, the extra attention and effort by property owners and managers are required. Examination of accidents indicated that 88% of them were stemmed from unsafe activities, 10% from unstable mentality and 2% from unavoidable natural disasters. Therefore, 90% of these accidents could be prevented by eliminating unsafe activities. In addition to the above findings, several other facts and suggestions are detailed.