• Journal of the Korean Institute of Gas
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• v.27 no.4
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• pp.62-69
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• 2023

The use of low-grade coal is continuously increasing with the development of combustion technology and cost reduction for coal used in thermal power plants . During combustion, the latent heat of evaporation due to moisture is large, and there is a risk of spontaneous combustion and dust explosion during the process of storing and pulverizing coal. This study compared and evaluated the minimum explosive concentration and explosive strength of four types of coal dust-fine, coal dust-coarse, wood pallet+organic dust, and wood chip with coal powder collected from domestic power plant D. The minimum explosive concentration of coal dust was measured according to JIS Z 8818:2002, and the explosion strength was tested according to ASTM E1226 using a Siwek 20 L Chamber Apparatus. As a result of the minimum explosive concentration test, it was found that coal dust-fine has a risk of dust explosion, and since an explosion occurs at a dust concentration of 130 g/m³ of wood chips, it was found that there is a risk of explosion at the lowest dust concentration. According to the dust explosion class standard, Kst is less than 200 bar m/s, and all samples fall under the explosion class St 1, and the dust has a low risk of explosion.

• Journal of The Korean Association For Science Education
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• v.27 no.1
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• pp.37-49
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• 2007

The purpose of this study was to classify the logical forms of scientific explanations provided by teachers in secondary earth science classrooms, to examine the characteristics of the scientific explanations in different forms, and to identify the roles of the teacher and students in discursive practices for scientific explanations. Data came from the earth science teachers who participated in overseas teacher in-service programs in the years 2003 and 2004. A total of 18 video-taped lessons and their verbatim transcriptions were analyzed. The result showed that deductive-nomological explanations occurred most frequently in earth science classrooms and that the deductive-nomological model was well-suited to those problems for which there existed firmly established scientific laws or principles to construct scientific explanations. However, abductive explanations were presented when the classes dealt with retrodictive tasks of earth science. The statistical-probabilistic and statistical-relevance models were also employed in explaining weather proverbs and unusual changes of weather, respectively. Most of the scientific explanations were completed through the teachers' monologic utterances, and students assumed passive roles in discursive practices for developing scientific explanations. Implications for science lessons and science education research were discussed.

• Journal of Music and Human Behavior
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• v.21 no.2
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• pp.51-75
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• 2024

This case study aimed to develop a therapeutic rap protocol based on narrative components for improving discourse skills of adolescents with mild intellectual disability (ID) and to explore its applicability. The protocol matched narrative elements (background, initiating event, internal response, attempts, and reaction) with rap components (verse, hook, and interjections), guiding participants to narrate their experiences in a connected discourse form. The protocol was also structured to gradually increase in difficulty, considering the developmental levels of adolescents with ID and it included steps for understanding discourse structures, applying narrative elements to content creation, and expanding narratives. Post-intervention analysis of the stories and rap lyrics created by participants to express their real-life experiences showed that participants increased the length of their stories and rap compositions, with notable improvements in rhythmicity and the inclusion of narrative elements. These findings suggest that, instead of constructing rap from random utterances, providing a structured framework reflecting discourse structure enhanced participants' understanding of event context and logical connections. Furthermore, the various elements and rhythmic features of rap can strengthen motivation and organization in discourse. This study highlights the therapeutic potential of rap in addressing the unique developmental needs of adolescents with mild ID, thereby diversifying and systematizing music therapy interventions for this population.

• Journal of Music and Human Behavior
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• v.4 no.1
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• pp.21-30
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• 2007

Unlike other common forms of speech disorder, such as phonological disorder or dysphonia, stuttering has not been studied within the context of music therapy. Most cases of stuttering display no difficulty in singing, and fluency within the musical structure does not translate to fluency in speech. Hence, musical approach has been generally considered to be ineffective to the treatment of stuttering. However, the fundamentals of music therapy assume its extensive application in treating variety of speech disorders, including the case of stuttering. Presented in this paper are the case studies designed to validate the efficacy of music therapy as a remedy for stuttering. This study enrolled 6 children with stuttering and conducted 20 individual sessions over a period of 10 weeks. The sessions focused on the Melodic Intonation Therapy, Reinforcement of speech rhythm, song writing and singing. Musical elements were structured to enhance the verbal expression and rhythmic senses, as well as to facilitate the initiation of verbal communication. The result is as follows. First, it was noticed that the disfluency had been decreased in before and after of the music therapy in every child although the result was somewhat different depending the child. The overall result of the investigation shows the significant difference statistically. And categorically speaking, the significant difference was checked in the frequency of the stuttering. In the steps of the session, the increase and decrease was happened repeatedly, and then after it was decreased little by little. Secondly, the Communication Attitude was decreased in before and after of the music therapy, and also there was significant difference statistically. although the avoidance behavior was decreased in before and after of the music therapy, the increase and the decrease was repeated irregularly in the steps of session. All the results described above shows that music therapy gives positive effect to decrease in disfluency of stuttering child and also to develop the Communication Attitude. And new possibility and effectiveness can be proposed in the musical approach to the stuttering.

• Issues in Feminism
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• v.18 no.2
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• pp.149-206
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• 2018

This essay is focused on finding women's voice in oral narratives of social memory of national violence and resistance. The books of oral narratives of women who had experienced the national violence and participated in the resistance through historic events such as 5.18, have been published recently. This study is based on the materials that have interviewed women experienced the historic event '5.18' in Gwangju. In this study, there are analyses of the materials of the memory of violence and resistance of '5.18', which have contained the texts written by intellectual males and the oral narratives of females directly involved. So far, the memory and experience of women have not been presented in its entirety in the field of social discourse of '5.18'. In the field women's words were translated in men's words, so the real words disappeared and in the end remained unspoken words. And besides, the existence of women are substituted with the limited images (for example women's body destroyed) presented by men's words in memorial materials. In narratives of '5.18', women are reduced to the images of bodies destroyed by national violence. The destroyed bodies are places for exhibition and disclosure of national violence. Women are not presented as the subjects of the social resistance in oral or written narratives of '5.18'. The images of females are only vehicles to urge the male subjects to resist against unjust violence. In this context, men are interpreted for the protectors of sisters, daughters, wives. Since 1980s, the symbol of '5.18 Gwangju' has represented the most ideal community in Korean society. But women have been on the borderline or outside of the community in fact. However, women intend to construct themselves as the subjects of resistance through the spoken words. They have tried to make the politic places for themselves in the social field by speaking and speaking constantly. The desire to speak out is becoming stronger for women, so these days more words are spoken by more women and more oral narratives made by women are revealed in social discoursive field. So the place for women's voice is expanding in social memorial field of '5.18'.

• Journal of The Korean Association For Science Education
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• v.36 no.1
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• pp.45-61
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• 2016

The purpose of this study is to explore students' epistemic goals and considerations in designing an experiment task and to investigate how a shift in the students' epistemology affected their argumentation. Four 7th grade students were selected as a focus group. According to the results, when they designed their own experiment, their epistemic goal was 'scientific sense-making' and their epistemic considerations - the perception of the nature of the knowledge product was 'this experiment should explain how something happened', the perception of the justification was 'we need to use our interpretation of the data' and the perception of the audience was 'constructor' - contributed to designing their experiment actively. When students tried to select one argument, their epistemic goal shifted to 'winning a debate', showing 'my experiment is better than the others' with the perception of the audience, 'competitor'. Consequently, students only deprecated the limits of different experiment so that they did not explore the meaning of each experiment design deeply. Eventually, student A's experiment design was selected due to time restrictions. When they elaborated upon their result, their epistemic goal shifted to 'scientific sensemaking', reviewing 'how this experiment design is scientifically valid' through scientific justification - we need justification to make members accept it - acting as 'cooperator'. Consequently, all members engaged in a productive argumentation that led to the development of the group result. This study lays the foundation for future work on understanding students' epistemic goals and considerations to prompt productive argumentation in science classrooms.

• Fire Science and Engineering
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• v.31 no.5
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• pp.53-62
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• 2017

Electric power which is the energy source of economy and industries requires long distance transportation due to regional difference between its production and consumption, and it is supplied through the multi-loop transmission and distribution system. Prior to its actual use, electric power flows through several transformations by voltage transformers in substations depending on the characteristics of each usage, and a transformer has the structure consisting of the main body, winding wire, insulating oil and bushings. A transformer fire that breaks out in substations entails the primary damage that interrupts the power supply to houses and commercial facilities and causes various safety accidents as well as the secondary economic losses. It is considered that causes of such fire include the leak of insulating oil resulting from the destruction of bottom part of bushings, and the chain reaction of fire due to insulating oil that reaches its ignition point within 1 second. The smoke detector and automatic fire extinguishing system are established in order to minimize fire damage, but a difficulty in securing golden time for extinguishing fire due to delay in the operation of detector and release of gas from the extinguishing system has become a problem. Accordingly, this study was carried out according to needs of active mechanism to prevent the spread of fire and block the leak of insulating oil, in accordance with the importance of securing golden time in extinguishing a fire in its early stage. A bushings fireproof structure was developed by applying the high temperature shape retention materials, which are expanded by flame, and mechanical flame cutoff devices. The bushings fireproof structure was installed on the transformer model produced by applying the actual standards of bushings and flange, and the full scale fire test was carried out. It was confirmed that the bushings fireproof structure operated at accurate position and height within 3 seconds from the flame initiation. It is considered that it could block the spread of flame effectively in the event of actual transformer fire.

• Cross-Cultural Studies
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• v.50
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• pp.77-101
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• 2018

Even in our modern era, the projection of monsters in the recent literature contains the critical imagination of human existence for the posthuman age. The meaning of the monster-abject, especially as from the perspective of feministic criticism, contains criticism of the violent and oppressive patriarch as observed in the modern times. This article focuses on the gendered imagination of the discussions of the "abject" discussed by Julia Kristeva, and the "monstrous femine" discussed by Barbara Creed. Kim Eon-Hee's poems and Han Kang's novels, which have been examined extensively for analysis, show that the practical strategy of abject that goes beyond hate and sublime, wonder and joy through the imagination and concepts of monsters. The monster-abject strategy of Kim Eon-Hee's poem can be summarized by the narrative method of mirroring and the imagination of the truncated body. Mirroring falsification, which mimics the male speaker, is a method that some feminists strategically utilize in relation to the problem of female aversion in recent years as noted in the literature. In Kim Eon-Hee's poem, "becoming a man" and "imitating a man," through the method of mirroring appear as an image of cutting to dismantle the body. In that way, the narrative strategy of the abject that draws out abominations and bizarre effects which contains a strong critique of the patriarchal dominant ideology. The monster-abject strategy of Han-Kang's novel is embodied through the being of plants and the process of vegetarian-anorexia process. The world of the adject which was oppressed in the Han-Kang's novel, returns to the senses of the body through the symbol of the body. It is noted that the fictional characters who realize the repressed desire through the pathological symptom expressed by the female, go on to body perform active transformation. The sense of a body in a novel is not only a rejection of the world of animalman-civilization, but also a radically questioning of the noted and recognized boundaries between human beings and non-human being entities. The two writer's works show that the imagination of the monster-adject is not limited to rejecting the existing gender categories, but also goes in the direction of exploring the possibilities of various associated gender actions.

• Journal of Intelligence and Information Systems
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• v.27 no.2
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• pp.17-32
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• 2021

Speaker recognition is generally divided into speaker identification and speaker verification. Speaker recognition plays an important function in the automatic voice system, and the importance of speaker recognition technology is becoming more prominent as the recent development of portable devices, voice technology, and audio content fields continue to expand. Previous speaker recognition studies have been conducted with the goal of automatically determining who the speaker is based on voice files and improving accuracy. Speech is an important sociolinguistic subject, and it contains very useful information that reveals the speaker's attitude, conversation intention, and personality, and this can be an important clue to speaker recognition. The final ending used in the speaker's speech determines the type of sentence or has functions and information such as the speaker's intention, psychological attitude, or relationship to the listener. The use of the terminating ending has various probabilities depending on the characteristics of the speaker, so the type and distribution of the terminating ending of a specific unidentified speaker will be helpful in recognizing the speaker. However, there have been few studies that considered speech in the existing text-based speaker recognition, and if speech information is added to the speech signal-based speaker recognition technique, the accuracy of speaker recognition can be further improved. Hence, the purpose of this paper is to propose a novel method using speech style expressed as a sentence-final ending to improve the accuracy of Korean speaker recognition. To this end, a method called sentence sequencing that generates vector values by using the type and frequency of the sentence-final ending appearing in the utterance of a specific person is proposed. To evaluate the performance of the proposed method, learning and performance evaluation were conducted with a actual drama script. The method proposed in this study can be used as a means to improve the performance of Korean speech recognition service.

• Phonetics and Speech Sciences
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• v.14 no.3
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• pp.87-101
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• 2022

In addition to administering a questionnaire (J-survey), which questions individuals on subjective vocal fatigue, voice samples were collected before and after speech-language pathology sessions from 50 female speech-language pathologists in their 20s and 30s in the Daejeon and Chungnam areas. We identified significant differences in Korean Vocal Fatigue Index scores between the fatigue and non-fatigue groups, with the most prominent differences in sections one and two. Regarding acoustic phonetic characteristics, both groups showed a pattern in which low-frequency band energy was relatively low, and high-frequency band energy was increased after the treatment sessions. This trend was well reflected in the low-to-high ratio of vowels, slope LTAS, energy in the third formant, and energy in the 4,000-8,000 Hz range. A difference between the groups was observed only in the vowel energy of the low-frequency band (0-4,000 Hz) before treatment, with the non-fatigue group having a higher value than the fatigue group. This characteristic could be interpreted as a result of voice abuse and higher muscle tonus caused by long-term voice work. The perturbation parameter and shimmer local was lowered in the non-fatigue group after treatment, and the noise-to-harmonics ratio (NHR) was lowered in both groups following treatment. The decrease in NHR and the fall of shimmer local could be attributed to vocal cord hypertension, but it could be concluded that the effective voice use of speech-language pathologists also contributed to this effect, especially in the non-fatigue group. In the case of the non-fatigue group, the rhamonics-to-noise ratio increased significantly after treatment, indicating that the harmonic structure was more stable after treatment.