• Research in Mathematical Education
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• v.19 no.2
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• pp.89-100
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• 2015

The study investigated pre-service teachers' knowledge and computational skills by using Triangular Arithmagon. Participants included 90 pre-service teachers from two schools in the United States and Taiwan. The Triangular Arithmagons Test (TAT) was used to measure pre-service teachers' performance in whole number, fractions, and decimals operations (i.e., addition, subtraction, multiplication, and division), each of which included level-1 (basic) and level-2 (advanced) tests. MANOVA analysis was performed to compare the performance between teachers from the United States and Taiwan. Results indicated that overall, pre-service teachers in Taiwan outperformed those in the United States, especially on the advanced-level tests. Pre-service teachers in the United States were found to have poor ability of solving complex operation problems. Different curriculum plans and teaching methods may lead to the performance gap between the two countries.

• Education of Primary School Mathematics
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• v.5 no.1
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• pp.41-55
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• 2001

The purpose of this study was to compare and analyze the curricula of kindergarten and elementary school and to present a plan for connecting the two curricula. The curricula emphasized mathematical thinking and problem solving instead of fragmentary knowledge and adopted the streamed curriculum based on children’s ability and interest. And both of them consisted of number and operation, geometry, measurement, statistics, and put emphasis on activity such as real life experience, play, manipulation of concrete objects, and communication. However, there are some kinds of differences between them, because the kindergarten curriculum is not included in the common curriculum, from 1st grade to 10th grade. Thus, this study recommended several ideas based. Thus, this study recommended several ideas based on theories to connect the mathematics curricula of kindergarten and elementary school.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.2
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• pp.204-210
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• 1988

The residue number system offers the possibility of high-speed operation and error detection/correction because of the separability of arithmetic operations on each digit. A compact residue arithmetic module named the self-checking pulse-train residue arithmetic circuit is effectively employed as the basic module, and an efficient error detection/correction algorithm in which error detection is performed in each basic module and error correction is performed based on the parallelism of residue arithmetic is also employed. In this case, the error correcting circuit is imposed in series to non-redundant system. This design method has an advantage of compact hardware. Following the proposed method, a 2nd-order recursive fault-tolerant digital filter is practically implemented, and its fault-tolerant ability is proved by noise injection testing.

• Nuclear Engineering and Technology
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• v.48 no.1
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• pp.114-128
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• 2016

The development of operational performance indicators is of utmost importance for nuclear power plants, since they measure, track, and trend plant operation. Leading indicators are ideal for reducing the likelihood of consequential events. This paper describes the operational data analysis of the information contained in the Corrective Action Program. The methodology considers human error and organizational factors because of their large contribution to consequential events. The results include a tool developed from the data to be used for the identification, prediction, and reduction of the likelihood of significant consequential events. This tool is based on the resilience curve that was built from the plant's operational data. The stress is described by the number of unresolved condition reports. The strain is represented by the number of preventive maintenance tasks and other periodic work activities (i.e., baseline activities), as well as, closing open corrective actions assigned to different departments to resolve the condition reports (i.e., corrective action workload). Beyond the identified resilience threshold, the stress exceeds the station's ability to operate successfully and there is an increased likelihood that a consequential event will occur. A performance indicator is proposed to reduce the likelihood of consequential events at nuclear power plants.

• Journal of Power Electronics
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• v.10 no.2
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• pp.155-164
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• 2010

This paper presents a voltage control algorithm for a hybrid multilevel inverter based on a staged-perception of the inverter voltage vector diagram. The algorithm is applied to control a three-stage eighteen-level hybrid inverter, which has been designed with a maximum number of symmetrical levels. The inverter has a two-level main stage built using a conventional six-switch inverter and medium- and low- voltage three-level stages constructed using cascaded H-bridge cells. The distinctive feature of the proposed algorithm is its ability to avoid the undesirable high switching frequency for high- and medium- voltage stages despite the fact that the inverter's dc sources voltages are selected to maximize the number of levels by state redundancy elimination. The high- and medium- voltage stages switching algorithms have been developed to assure fundamental switching frequency operation of the high voltage stage and not more than few times this frequency for the medium voltage stage. The low voltage stage is controlled using a SVPWM to achieve the reference voltage vector exactly and to set the order of the dominant harmonics. The inverter has been constructed and the control algorithm has been implemented. Test results show that the proposed algorithm achieves the desired features and all of the major hypotheses have been verified.

• Journal of Korean Port Research
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• v.13 no.2
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• pp.245-254
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• 1999

This paper aims to derive the strategies for the container terminal in Pusan. So it has focused on analyzing the current conditions of Pusan container terminal while evaluating the difficulties arising from the existing facilities/equipment and the operating system in the Pusan Korea Container Terminal through the workers at the container terminal and at off-dock CY. The object of this study is to assist the existing terminals to operate the facilities/equipment reasonably and to contribute shaping the ports policy which will be the basis of constructing new ports that will remain competitive while maintaining superiority over the ports in northeast area. According to the analysis 68% of the supplier answered that their terminal services which are the most important factor in running a terminal were superior to the other while only 28% of the user answered that they thought the current services were superior. For the areas of supplementing the terminal the people working at the terminal answered in the order of business operation equipment the number of berth service and management ability while the user answered in the order of service computer system transportation system and equipment. According to the regression analysis it became clear that there should be more effort toward improving or supplementing the facility scale facility usage charge transportation facilities which will assist in developing competitiveness of the terminal. It was also noted that management ability and business ability were mentioned as the important factors in operating a terminal.

• Journal of the Korean Society for Railway
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• v.19 no.2
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• pp.234-242
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• 2016

In express operation plans for urban trains, it is effective for the reduction of the number of sidetracks to apply a high performance train that has improved acceleration/deceleration ability and a regular train to local and express trains, respectively. In this research, based on a plan to use a high performance train for a local train, an optimization methodology is suggested to reduce the number of sidetracks and the operation time of the local train simultaneously. The optimization solver applied in this research is a genetic algorithm; headway, location of sidetrack and waiting time at the sidetrack are considered as design variables in the optimization problem. Consequently, by applying this system to Seoul metro line no.7, the effect of the suggested methodology was verified by obtaining the proper optimum solution.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.30 no.3
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• pp.291-314
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• 2019

In this study, to improve the satisfaction of library users in the hospital and to examine how to activate the library in the future, the satisfaction of library, facilities and environment, staff, service, We conducted a demand survey and searched for the operation plan of the library that satisfied the user. As a result, in order to revitalize the library in the hospital, first, in the case of the collection, it is necessary to expand the number of collections of various topics with the latest contents. Second, it is urgent to expand the number of library staff in the hospital. In addition, it is necessary to improve communication expertise based on medical expertise and ability to respond quickly to user requests. Third, it is necessary to expand the size of library and convenience facilities in the hospital by facilities and environment. Fourth, in case of service, it is necessary to improve service quality and provide various services. Experts should provide subject search service, medical information source service, general health information service (patient and carer) according to the user. Finally, in the case of programs, it is necessary to expand the infrastructure for program operation, to diversify the targets, and to extend the program continuity.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.3
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• pp.71-82
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• 2016

The ISO (International Organization for Standardization) 9000 QMS (Quality Management System) standards specify requirements that need to demonstrate an organization's ability to consistently provide products or services. Korean companies have been implementing ISO 9000 QMS to compete in global markets. ISO 9000 QMS standards have been revised in 1994, 2000, 2008, and 2015 since the first release in 1987. The key change in ISO 9001:2015 is focused on risk-based thinking. It means that risk inherent within an organization is early identified and proactively controlled by use of all aspects of QMS rather than taking preventive actions. In this article we did literature review mainly on empirical study related to motivation and operation performance of ISO 9000 implementation. We present the necessity of changeover, features of new version, and comparison between new and old version. In order to see how well organizations can implement the new ISO 9001:2015 we focus on manufacturing companies that are going to convert to ISO 9001:2015 registration. We collect their key characteristics such as yearly sales, the number of MPI (Management Performance Indicators), the number of KPI (Key Performance Indicators), the number of quality control engineers, quality control engineer work experience, and the degree of adaptiveness between new ISO 9001:2015 QMS and QMS currently operating in manufacturing companies. Especially the degree of adaptiveness is analyzed by correlation analysis, regression analysis, ANOVA, and t-tests to discover the relationships among their characteristics. We found out that the degree of adaptiveness is linearly related to quality control engineer work experience and the number of MPI and KPI that is practically utilized in manufacturing companies. We summarize the implications discovered to help manufacturing industry convert to ISO 9001:2015 registration.

• Journal of Korean Society of Forest Science
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• v.104 no.4
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• pp.607-614
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• 2015

This study aims to analyze the current status of timber production operation and the effects of the forestry mechanization projects on timber production. In order to increase the domestic timber production, it is necessary to propel forestry mechanization project, improve policy and institution, broaden forest-road network, enlarge the number of forest workers, enhance timber production and supply system, provide forestry machines, establish forest operation system, and train forest workers. In addition, the reestablishment of policy goals, the consistency of policy, and the rearrangement of laws and institution are considered more important. To improve the results and effects of forestry mechanization project, it is necessary to drive of forestry mechanization project, the spread of forestry machines, the cultivation of trainer ability, the development of training materials, and the teaching of field skill. In order to meet timber buyersí preference, timber needs to be produced through whole tree logging operation system. Expanding the proportion of domestic timber among total timber demand in Korea requires price competitiveness, and the supply ability of high quality product from the perspective of length and width.