• Journal of the Korean Operations Research and Management Science Society
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• v.18 no.2
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• pp.1-22
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• 1993

This paper deals with the problem of mixed model assembly line balancing. In mixed model assembly lines, tsks should be assigned to stations in such a manner that all stations have approximately the same amount of work on a production cycle basis. Further in balancing assembly lines, the related tasks, the performing task side and the team tasks should be considered to improve work methods, to give more job satisfaction to workers, and to allow greater flexibility in the design of assembly lines. In this paper, the heuristic dispatch assignment rule is developed to assign evenly tasks of each model to all stations. The heuristic method based on the assignment rule developed is presented for mixed model assembly line balancing with the considerations of the related tasks, the performing task side, and the team tasks. The proposed method is analyzed, and compared with other methods for line balancing.

• MALSORI
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• no.61
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• pp.31-48
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• 2007

This study investigated the roles of name agreement and word frequency in the English-Korean word translation task. Using the low-frequency homonyms with low name agreement as stimuli, Experiment 1 revealed that the name agreement of materials is a determinant which could modulate times to translate English words into Korean equivalents. On the contrary, Experiment 2 showed that the name agreement of materials does not play a decisive role in the translation task, using the low-frequency homonyms having high name agreement as stimuli. In Experiment 3, we identified that the frequency effects observed from previous two experiments are indeed brought about during the lexical access. Our findings suggest that the word frequencies of materials have a strong influence on English-Korean word translation times, and homonyms are represented independently each other in the lexeme level.

• Industrial Engineering and Management Systems
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• v.4 no.1
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• pp.36-46
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• 2005

In traditional production lines, such as assembly lines, each worker is usually assigned to a fixed task, which is beneficial since it reduces the amount of training needed for workers to master their assigned tasks. However, when workers complete their tasks at different speeds, the slowest worker will determine the overall pace of the production line and limit production. To avoid this problem, the self-balancing production line was introduced. In this type of production line, each worker works dynamically, thus they can maintain balanced production. Previous research analyzing the performance of these lines has ignored the walk-back time associated with dynamic workers. U-shaped production lines have also been analyzed and policies for such lines have been proposed. However, the walk-back time cannot be ignored in practice, and research taking this factor into account is needed to enable balanced production and thus the maximum production rate. In this paper, we propose production policies for a production line with the walk-back time taken into account, and define and analyze the conditions for self-balancing. Furthermore, we have compared the performance of such a line with that of other production lines under the same conditions, and the results show the superiority of this line in certain cases.

• Phonetics and Speech Sciences
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• v.2 no.4
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• pp.109-118
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• 2010

Using a speeded classification task (Garner, 1978), we investigated the perceptual interaction of distinctive features in Korean consonants. The main questions of this study were whether listeners can perceptually identify the component features that make up complex consonant sounds, whether these features are processed independently or dependently and whether there is a systematic hierarchy in their dependency. Participants were asked to classify syllables based on their difference in distinctive features in the task. Reaction times for this task were also gathered. For example, participants classified spoken syllables /ta/ and /pa/ as one category and /$t^ha$/ and /$p^ha$/ as another in terms of aspiration condition. In terms of articulation, participants classified /ta/ and /$t^ha$/ as one category and /pa/ and /$p^ha$/ as another. We assumed that the difference between their RTs represents their interdependency. We compared the laryngeal features and place features (Experiment 1), resonance features and place features (Experiment 2), and manner features and laryngeal features (Experiment 3). The results showed that distinctive features were not perceived in a completely independent way, but they had an asymmetric and hierarchical interdependency. The laryngeal features were found to be more independent compared to place and manner features. We discuss these results in the context of perceptual basis in phonology.

• Phonetics and Speech Sciences
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• v.13 no.2
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• pp.1-7
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• 2021

Speech is a spatiotemporally coordinated structure of constriction actions at discrete articulators such as lips, tongue tip, tongue body, velum, and glottis. Like other human movements (e.g., reaching), each action as a linguistic task is completed by a synergy of involved basic elements (e.g., bone, muscle, neural system). This paper discusses how speech tasks are dynamically related to joints as one of the basic elements in terms of robotics of speech production. Further this introduction of robotics to speech sciences will hopefully deepen our understanding of how speech is produced and provide a solid foundation to developing a physical talking machine.

• The Journal of Economics, Marketing and Management
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• v.5 no.1
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• pp.21-26
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• 2017

Purpose - This study extracts performance-reward factors based on the previous studies related to Herzberg's two-factor theory and performance-reward and proposes a research method to identify how these factors have an influence on task performance directly related to production performance and contextual performance that has an indirect influence. Research Design, Data, and Methodology - This study draws performance-reward factors through Focus Group Interview(FGI), classifies them into economic/uneconomic and direct/indirect factors, draws maintenance/improvement factors and unnecessary ones through IPA, and maximizes the effectiveness of performance-reward factors. Results - It also identifies how performance-reward factors have an influence on internal and external motives based on previous studies, classifies performance-reward factors into task performance and contextual performance and identifies the influence relationship between these, and proposes a research model to identify the roles of equity sensitivity based on equity theory. Conclusion - The findings from this study are expected to lay the groundwork for drawing various methods to reduce the turnover rate of employees and be important resources for reinforcing the competitiveness of businesses by classifying the performance -reward factors that may cause internal and external motives from the small and medium-sized manufacturing perspective and presenting methods to identify if these have an influence on task performance and contextual performance.

• Journal of the Korea Society for Simulation
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• v.25 no.2
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• pp.75-81
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• 2016

By using simulation, fixed location production method and flow production method have been compared to improve the productivity of deckhouse preceding outfitting process. In this paper, we analyze that the suggested flow production system instead of fixed location production can improve productivity. In current preceding outfit production system which adopts fixed location production, where a block occupies an area and does not move until the work finishes. On the other hand, in improved flow production system, the block moves instead of workers and equipment. Though the output of two systems are almost the same when we did not consider the moving time and waiting time of blocks, the flow production will be better when the variability of task time will be reduced.

• Proceedings of the KSPS conference
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• 2002.11a
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• pp.165-168
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• 2002

This research was conducted to investigate the priming effect in Korean and English word production by Korean speakers. Picture-naming with distractors was used as experimental task. The type of target language, the type of distractor language and SOA(Stimulus Onset Asynchrony) were used as variables. Cross-linguistic priming effect and within-linguistic priming effect were mesured to investigate bilinguals' conceptual system.

• Journal of the Korean Operations Research and Management Science Society
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• v.24 no.4
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• pp.13-26
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• 1999

When we try to design a production planning system for a manufacturing company, it is a time consuming task to analyze various planning activities and identify inter-relationship among a lot of decisions made for the production planning. Most of the research efforts have been concentrated to well-organized independent decision-making problems that may usually be identified only after analyzing the characteristics of the decision-making process as a whole. In this paper, a methodology is suggested to characterize the whole process of the production planning for a manufacturing company and reduce the complexity of decision-making problems. The methodology is based on an experience of developing a production planning software for an automobile component manufacturer in korea. First, it is explained how to identify and represent the dependency among various decision-making variables. And a methodology is proposed to analyze the identified dependency among decision variables and identify decision-making process. Lastly, a practical example is provided to illustrate the analysis procedure in this paper.

• English Language & Literature Teaching
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• v.18 no.1
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• pp.23-43
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• 2012

This study investigates the effects of three different types of instruction, namely form-based, comprehension-based, and production-based on the development of Korean university students' (n=137) comprehension and production of English relative clauses (RCs). The extent of improvements was analyzed by administering pre-and post-tests consisting of two comprehension tests (selecting the right form of RCs and the right picture descriptions) and one production test (combining two sentences). Findings of this study suggest that all three types of instruction increased participants' comprehension and productions of RCs. However, there appeared differential effects by the instruction type. It was found production-based instruction was most effective in promoting comprehension, followed by comprehension-based instruction. Comprehension-based instruction worked best with the development of production, suggesting that the effects of comprehension training did not only work for increasing comprehension skills, but also transfer to production skills. The type or level of tasks employed for each instruction appeared to play an important role in causing such results. Form-based instruction displayed the lowest improvements in both comprehension and production of RCs. A sentence-combination task employed for form-based instruction appear to result in mere explicit rule explanations without chances to notice rules in context or use their knowledge in practice.