• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.6
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• pp.553-581
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• 2022

Shortly after tunnel boring machine (TBM) was introduced in the tunneling industry, the use of TBM has surprisingly increased worldwide due to its performance together with the benefit of being safely and environmentally friendly. One of the main cost items in the TBM tunneling in rock and soil is changing damaged or worn cutters. It is because that the cutter change is a time-consuming and costly activity that can significantly reduce the TBM utilization and advance rate and has a major effect on the total time and cost of TBM tunneling projects. Therefore, the importance of accurately evaluating the cutter life can never be overemphasized. However, the prediction of cutter wear in soil, rock including mixed face is very complex and not yet fully clarified, subsequently keeping engineers busy around the world. Various prediction models for cutter wear have been developed and introduced, but these models almost usually produce highly variable results due to inherent uncertainties in the models. In this study, a case study of design and construction of disc cutter change is introduced and analyzed, rather than proposing a prediction model of cutter wear. As the disc cutter is strongly affected by the geological condition, TBM machine characteristic and operation, authors believe it is very hard to suggest a generalized prediction model given the uncertainties and limitations therefore it would be more practical to analyze a real case and provide a detailed discussion of the difference between prediction and result for the cutter change. By doing so, up-to-date idea about planning and execution of cutter change in practice can be promoted.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.4
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• pp.585-591
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• 2019

Objective: This study investigated carcass characteristics and meat quality of purebred Pakchong 5, crossbred pigs sired by Pakchong 5, and crossbred pigs sired by Duroc. Methods: Forty-eight pigs (average body weight of 22.25 kg) were composed of three groups as purebred Pakchong 5 (PP), Large $White{\times}Landrace$ pigs sired by Pakchong 5 (LWLRP), and Large $White{\times}Landrace$ pigs sired by Duroc (LWLRD). Each group consisted of eight gilts and eight barrows. At 109-day-raising period, pigs were slaughtered, and carcass characteristics were evaluated. Longissimus thoracis (LT) muscles from left side of carcasses were evaluated for meat quality and chemical composition. Data were analyzed using general linear model procedure, where group, sex, and their interaction were included in the model. Results: The PP had greater carcass, total lean, and ham percentages than crossbred pigs (p<0.05). LWLRP had thicker backfat and more carcass fat percentage than LWLRD (p<0.05). There were no differences (p>0.05) on cutting percentages from tender loin, loin, boston butt, and picnic shoulder among groups. The PP and LWLRP had larger loin eye area (LEA) than LWLRD (p<0.05). Gilts had more loin percentage and lower $L^*$ value than barrows (p<0.05). No meat color parameters ($L^*$, $a^*$, and $b^*$) were affected by groups (p>0.05). PP and LWLRP had larger muscle fiber diameters than LWLRD (p<0.05). However, water holding capacity, Warner-Bratzler shear force values, and chemical composition of LT were not affected by group or sex (p>0.05). Conclusion: Pakchong 5 purebred has good carcass and lean percentages. Compared to Duroc crossbred pigs, Pakchong 5 crossbreds have similar carcass and lean percentages, larger LEA, and slightly more carcass fat, with comparable meat quality and chemical composition. Pakchong 5 boars are more affordable for very small- to medium-scale pig producers.

• Journal of Korea Entertainment Industry Association
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• v.13 no.3
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• pp.269-278
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• 2019

This study is intended to present the direction of art mask design development and help people's life care by producing an art mask with the motif of the characteristic of abjection concept. It went through the definition and characteristics of abject and abjection focusing on previous research, professional books and art works. The characteristics of abjection based on theoretical research are to express death with dead bodies and skulls, including the dismantling of ideal beauty standards, the expression of fragmented bodies, and the expression of sick and alienated bodies. This researcher produced 6 research works by combining the fascinating abjection, induced by ugly and disgusting abject, to design factors. These works fragmented each part of the facial form by the cutting and dismantling, and made viewers feel the abjection by giving a grotesque deformation. The results obtained through the research works are as follows. First, It was found that the abjection characteristics-applied works was helpful in the treatment of the mental wound of modern people. Second, the production of works based on the abjection characteristics paved the way to expand the scope of art mask design concepts and establish the new design ideas. Third, the application of the motif using the abjection characteristics to the art mask design showed that the use of various objects could express creative designs and secure diversity in using materials. In the future, this researcher hopes that such research will be used as the basic data of the follow-up study on art mask design, and it will help develop art mask designs.

• Anxiety and mood
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• v.7 no.1
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• pp.48-53
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• 2011

Objective : Korean Version of Beck-II Depression Inventory to verify the reliability and validity of the proposed standards are practical and standardized, cut-off score by establishing a baseline indicating the presence of depression and depression On in the evaluation was to evaluate the clinical usefulness. Methods : 739 patients with major depression using the SCID and normal controls were 302 study subjects. Of patients with clinically significant medical condition, or psychotic disorders, organic mental disorder, epilepsy or seizure disorder, eating disorders are associated with patients taking anti-convulsants experienced in the past, patients were excluded from the study. Results : The main findings of this study were as follows. First, with respect to the KBDI-II items, the correlation between them ranged from 0.51 to 0.74, and was 0.60 over all questions. Further, the overall correlation of the KBDI-II plates showing confidence 'normal' than it was verified that. Second, the BDIII was used in each group to examine internal consistency and thus, whether Cronbach's alpha values were greater than 0.94. Third, the principal component analysis sought to extract factors in a way consistent with the results inspected last 3 factors were extracted and the total variance explained was 47.3%. Fourth, the Cutting calculated the score on the KBDI-II for ROC (Receiver operator characteristic) analysis yielding 18 dot, with the highest sensitivity and specificity was seen. Conclusion : Based on the results of this Study, the KBDI-II cut-off point should be valid as prescribed in 18 is considered.

• Korean Journal of Psychosomatic Medicine
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• v.9 no.2
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• pp.153-163
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• 2001

This study was attempted to investigate the discriminant validity of Korean version of Eating Attitude Test-26(KEAT-26) and to provide the sensitivity, specificity and efficiency according to cutting score, which may be useful to determine the optimal cutoff point on various purposes. The KEAT-26 was administered to 108 female patients with eating disorders, 179 female participants in body slimming center, 120 female athletic college students, 227 female college students, and 183 healthy normal women. Validity was tested by ANOVA and ROC curve analysis. The results revealed that the total score of the KEAT-26 showed a statistically significance between groups and that the score of the KEAT-26 of eating disorders group was significantly higher than that of the other groups in post hoc test. In comparison of the 4 subfactor score of the KEAT-26 between groups, significant differences in main effect within groups were found in all subfactors except factor IV. ROC curve analysis showed 80% of efficiency to discriminate eating disorders group from normal control group using cutoff score on maximum discriminant efficiency and 69% of efficiency to discriminate eating disorders group from high risk groups for eating disorders. Each cutoff score on maximum in efficiency was as follows ; 25 between eating disorders group and participants in body slimming center, 19 between eating disorders group and healthy normal woman, 23 between eating disorders group and athletic college students, 21 between eating disorders group and college students. Using 22(T score 65) of the KEAT-26 as the cutoff score, sensitivity was 54%, specificity was 84%, and overall efficiency was 80%. These results indicate that the KEAT-26 has a good discriminant validity in Korean population and also suggest that the KEAT-26 may be useful assessment tool to screen the disordered eating problems on clinical and epidemiological purposes.

• Journal of Science Education
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• v.38 no.3
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• pp.525-542
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• 2014

This study was performed to look into the difficulty of students in understanding science stories in 6th grade science textbooks and to analyze those factors. To do this, 6th grader (N=65) were selected from J Elementary School located in Gyeonggi-do Siheung-si as study subjects. 26 science stories in 6th grade science textbooks were classified by field and context (complement of knowledge, science history of scientists, science in life, cutting-edge science technology, environment issues) in which the characteristics were investigated and analyzed. Also, a survey about the difficulty in understanding science stories(26 items) was conducted(65 students) and a semi-structured interview was conducted for students to clarify the meaning of collected data from surveys(4 students). As result of analyzing surveys on science story context in science textbooks and interviews, 4 fields of 'energy,' 'matter,' 'life,' and 'earth' were evenly mentioned. Science in life and complement of science knowledge were mentions most for context and this had relation with the characteristic of science textbooks to provide many opportunities to apply learned knowledge in actual social issues. Reactions of students on science stories were mostly positive that they help studying science, but there was also difficulty in well understanding science stories. Difficulty of understanding context, problems of context suggesting methods, difficulty of science terminology, lack of interest, and etc. were analyzed as factors. Specific causes were mentioned to be description type class, unimportant context, lack of explanation on suggested context, problem of pictures by students.

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.767-786
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• 2011

This study analyzed and compared characteristic of vegetation structure in Bonghwa mountain, the base Mt. outside urban area, and Hakseoung neighborhood park, Ilsan neighborhood park and Musil neighborhood park, disconnected residual Mt. inside urban area of Wonju. Regarding vegetation of urban forest in Wonju, Quercus mongolica forest and Robinia pseudo-acacia forest were widely distributed in the base Mt. outside urban area. Quercus acutissima forest and Robinia pseudo-acacia forest were widely distributed in the disconnected residual Mt. inside urban area. Forests in both areas were managed as part of forest management campaign. Analysis on importance value of a community classified by DCA and DBH class categorized communities into three groups according to the expected ecological succession. Community B was the one to be maintained as Pinus densiflora community. Community A, D and d were expected to be maintained as Quercus spp. Community. Community C, E, F, e, f and g were classified as exotic plant community. Ecological succession was suspended in both base Mt. outside urban area and disconnected residual Mt. inside urban area. However, importance value of Quercus spp. which appeared in the understory layer and shrub layer and their DBH class showed that the potential for ecological succession of exotic plant community was higher in base Mt. outside urban area than disconnected residual Mt. inside urban area. According to the analysis on number of species and individuals and species diversity, understory and shrub layer were reduced due to Forest Management campaign and plant species which appear at an earlier stage of succession varied as time went by since the campaign began. Species diversity comparison between natural and artificial forest showed no clear difference in both base Mt. outside urban area and disconnected residual Mt. inside urban area due to man-made disruption such as thinning and brush cutting. Six communities in base Mt. outside urban area had 17.76~52.22% of similarity index. Four communities in disconnected residual Mt. inside urban area showed 13.34~37.01% of similarity index, which was lower than base Mt. outside urban area. Among naturalized plants, Tupatorium rugosum and Phytolacca americana appeared more in disconnected residual Mt. inside urban area.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.1
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• pp.121-137
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• 2022

The purpose of this study is to present the necessary success factors and strategies for high-tech social ventures and stakeholders in the related ecosystem by empirically identifying factors that affect their sustainable performance. Based on prior research, the dimensions of three performance factors were presented: core technology competency, core business competency, and social mission orientation. Then, such sub-dimensions such as technology innovation orientation, R&D capability, business model, customer orientation, social network, and social mission pursuit were derived. For empirical analysis, a survey was conducted on domestic high-tech social ventures, and the significance of the hypothesis was tested through PLS-structural equation analysis of the collected 243 valid data. As a result, it was found that the technology innovation orientation was embedded as an abstract organizational and cultural characteristic in the high-tech social venture, which is a research sample, and thus did not significantly affect the dependent variable. In other words, aiming for the latest cutting-edge technology alone cannot affect performance, and it is a result of proving the need for substantial influencing factors that can strengthen it. On the other hand, the business model had a significant effect only on social performance, which is presumed to be the limitation of measurement tools developed for social enterprises, and the results of additional multi-group analysis to determine the cause also supported the basis for this estimation. Excluding the previous two performance factors, R&D competency, customer orientation, social network, and social mission pursuit were all found to have a significant positive (+) effect on social and economic performance. This study laid a foundation for related research by identifying high-tech social ventures emerging in the ecosystem of a social economy and expanded empirical research models related to the performance of existing social enterprises and social ventures. However, in the research method or process, there were limitations such as factor derivation or verification for balance of dual performance, subjective measurement method, and sample representativeness. It is expected that more in-depth follow-up studies will continue by supplementing future limitations and designing improved research models.

• Restorative Dentistry and Endodontics
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• v.25 no.3
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• pp.390-398
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• 2000

The purpose of this study was to evaluate the apical fitness of non-standardized gutta-percha cones in root canals prepared with rotary Ni-Ti root canal instruments of various tapers and apical tip sizes. Simulated sixty curved root canals of plastic blocks were prepared with crown-down technique using rotary root canal instruments of Maillefer ProFile$^{(R)}$ .04 and .06 taper (Maillefer Instrument SA, Switzerland). Specimens were divided into six groups and prepared as follows: Group 1, prepared up to size 25 of .04 taper ; Group 2, prepared up to size 30 of .04 taper ; Group 3, prepared up to size 35 of .04 taper ; Group 4, prepared up to size 25 of .06 taper ; Group 5, prepared up to size 30 of .06 taper ; Group 6 ; prepared up to size 35 of .06 taper. After cutting off the coronal portion of plastic, blocks perpendicular to the long axis of the canal with the use of a diamond saw, apical 5mm of canal space was analyzed. Prepared apical canal spaces were duplicated using rubber base impression material to evaluate two dimensional total area of apical canal space. Various sized gutta-percha cones were applied in the 5mm-apical canal space, which were size 25, size 30 and size 35 standardized gutta-percha cone, Diadent Dia-Pro ISO-.04$^{TM}$ and .06$^{TM}$(Diadent, Korea), and medium-fine (MF), fine (F), fine-medium (FM) and medium (M) sized non-standardized gutta-percha cones (Diadent, Korea). Coronal excess gutta-percha were cut off with a sharp blade. Photographs of impressed apical canal spaces and gutta-percha cones were taken with a CCD camera under a stereomicroscope and stored in a computer. Areas of the total canal space and gutta-percha cones were calculated using a digitalized image analysing program, CompuScope (Sungjin Multimedia Co., Korea). Ratio of apical fitness was obtained by calculating the area of gutta-percha cone to the total area of the canal space. The data were analysed statistically using One-way Analysis of Variance and Duncan's Multiple Range Test. The results were as follows: 1. In canals prepared up to size 25 ProFile$^{(R)}$ of .04 taper, non-standardized MF and F cones occupied significantly more canal space than Dia-Pro ISO-.04$^{TM}$ or size 25 standardized ones (p<0.05). 2. In canals prepared up to size 30 ProFile$^{(R)}$ of .04 taper, non-standardized F cones occupied significantly more canal space than Dia-Pro ISO-.04$^{TM}$ or size 30 standardized ones (p<0.05), and non-standardized MF cones occupied more canal space than size 30 standardized ones (p<0.05). 3. In canals prepared up to size 35 ProFile$^{(R)}$ of .04 taper, there was no significant difference in canal space occupation among non-standardized MF and F, size 35 standardized, and Dia-Pro ISO-.04$^{TM}$ cones (p>0.05). 4. In canals prepared up to size 25 ProFile$^{(R)}$ of .06 taper, non-standardized MF and F cones occupied significantly more canal space than Dia-Pro ISO-.06$^{TM}$, or size 25 standardized ones (p<0.05), and Dia-Pro ISO-.06$^{TM}$, cones occupied significantly more space than size 25 standardized ones (p<0.05). 5. In canals prepared up to size 30 ProFile$^{(R)}$ of .06 taper, non-standardized FM cones occupied significantly more canal space than Dia-Pro ISO-.06$^{TM}$ or size 30 standardized ones (p<0.05), and non-standardized F cones occupied significantly more canal space than size 30 standardized ones (p<0.05). 6. In canals prepared up to size 35 ProFile$^{(R)}$ of .06 taper, non-standardized M and FM, Dia-Pro ISO-.06$^{TM}$ occupied significantly more canal space than size 35 standardized ones (p<0.05). In summary, in both canals prepared with .04 or .06 taper ProFile$^{(R)}$, non-standardized cones showed better fitness than Dia-Pro ISO$^{TM}$ or standardized ones, which was more characteristic in smaller canals.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.36 no.4
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• pp.39-49
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• 2018

"Annals of The Joseon Dynasty" is a book recording the Joseon Dynasty's historical facts in an annalistic format. The King's amusement activities through "Annals of The Joseon Dynasty" which were established by the Ye-ak(禮樂) system were analyzed. The results are as follows. The king's amusement activities that were performed during the Joseon Dynasty period could be classified as state banquets, military banquets, and banquets for play. The analysis of the king's amusement activity was divided into five stages. The characteristic of [1 period : King Taejo~Sejo(Yejong)] was dominated the military banquets of the Goryeo Dynasty. Neo-Confucianism is the establishment of political and social turning of the ballast, considerations of military culture, culture, and Hoeryeyeon Jinpungjeong, a cloud of dust and elders banquets such as Giroyeon and Yangnoyeon on the nature of the party. A lasting ordinance was institutionalized[2 period : King Seongjong~Jungjong]. In the chopper and jeongyujaeran, Hong Kyung Rae led a royal amusement activities are stagnant, often produce isolated storage compute in the gloomy situation[3 period : King Injong~Hyeonjong]. Revival period is pride of the amusement activity through the culture of Joseon Dynasty royal culture [4 period : King Sukjong~Jeongjo]. The throne, crashed due to political power is an ebb of royal amusement activities, while also rapidly waning[5 period : King Seonjo~Seonjong]. During the early Joseon Dynasty, hunting took place around the forest area northeast of Hanyang and during King Seongjong's period, it took place closer to the capital city, while in Lord Yeonsan's period, it was expanded to a 39 kilometer radius area from the palace, and banquets such as various forms of entertainment of Cheoyongmu, and Flower-viewing. The Joseon kings who enjoyed hunting were King Sejong, Sejo, Seongjong, Yeonsan, and Jungjong. Most of hunting objects were tigers, bears, deer and roe deer, leopards, boars, their animals and falconry took, and the purpose of the hunting was to perform ancestral rites to the royal ancestry or the royal tombs. Lord Yeonsan's hunting activities had negative effects after King Jungjong the king's hunting activity decreased sharply. However, there were also positive aspects of Lord Yeonsan's Prohibition of cutting woods ect. In conclusion, the expansion of the King's garden(庭:courtyard${\rightarrow}$園:privacy garden${\rightarrow}$苑:king's garden${\rightarrow}$苑?:national hunting park) is evident which starts from formal and informal activities that took place in Oejo, Chijo, and Yeonjo, which went further to the separate and secret gardens, and then even further, thus setting the amusement activity area as a 39 kilometer radius range from Hanyang.