• Computers and Concrete
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• v.32 no.2
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• pp.173-184
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• 2023

In this study, mechanical, flexural post-cracking, and torsional behaviors of recycled steel fiber-reinforced concrete (RSFRC) incorporating steel fibers obtained from recycling of waste tires were investigated. Initially, three concrete mixes with different fiber contents (0, 40, and 80 kg/m³) were designed and tested in fresh and hardened states. Subsequently, the flexural post-cracking behaviors of RSFRCs were assessed by conducting three-point bending tests on notched beams. It was observed that recycled steel fibers improve the post-cracking flexural behavior in terms of energy absorption, ductility, and residual flexural strength. What's more, torsional behaviors of four RSFRC concrete beams with varying reinforcement configurations were investigated. The results indicated that RSFRCs exhibited an improved post-elastic torsional behaviors, both in terms of the torsional capacity and ductility of the beams. Additionally, numerical analyses were performed to capture the behaviors of RSFRCs in flexure and torsion. At first, inverse analyses were carried out on the results of the three-point bending tests to determine the tensile functions of RSFRC specimens. Additionally, the applicability of the obtained RSFRC tensile functions was verified by comparing the results of the conducted experiments to their numerical counterparts. Finally, it is noteworthy that, despite the scatter (i.e., non-uniqueness) in the aspect ratio of recycled steel fiber (as opposed to industrial steel fiber), their inclusion contributed to the improvement of post-cracking flexural and torsional capacities.

• Geomechanics and Engineering
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• v.32 no.4
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• pp.361-373
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• 2023

This study aimed to investigate the engineering properties and mechanical behaviors of polymer-fibers treated sand. Para rubber (PR), natural fiber (NF), and geosynthetic fiber (GF) were used to reinforce poorly graded sand. A series of unconfined compressive and splitting tensile strength tests were performed to analyze the engineering behaviors and strength enhancement mechanism. The experiment results indicated that the PR-fibers mixture could firmly enhance the strength properties of sand. The stress-strain characteristics and failure patterns have been changed due to the increase of PR and fibers content. The presence of PR and fibers strengthened the sand and enhanced the stiffness and ductility behavior of the mixture. The stiffness of reinforced sand reaches an optimum state when both NF and GF are 0.5%, while the optimum PR contents are 20% and 22.5% for the mixture with NF and GF, respectively. An addition of PR and fiber into sand contributed to increasing interlocking zone and bonding of PR-sand interfacial.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.5 no.1
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• pp.1-18
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• 2010

Cultural industry along with cultural content that forms the center of cultural industry is the field whose interest is continually increasing due to the increase of weight in the national economy and the strengthening of importance in future value. Cultural content, particularly, accounts for the essential position in starting a business around one-person business, which recently arouses high interest in a nation. However, it is true that the debates on the rapid growth and identity of cultural content in contrast to the reinforcement of its position, and the criticisms about the lack in development of material and cultural content in staring a business show the limitation of overall cultural content in Korea. This research examines recognition of cultural industry or cultural content through terminologies of definition as well as the relationships of configures in accordance with the outcome of cultural content. Findings demonstrate that cultural content in Korea revealed the highest cultural orientation which is the same as existing interpretations, and as comparison objects, entertainment industry in the U.S. and creative industry in the UK contained the highest part of entertainment and creativity respectively. It reflects that mythical elements of language that has been discussed from the structuralist perspectives are projected in the relevant field. In conclusion, the conceptual definition of cultural content has the structure to project advantages and disadvantages of existing culture, and this limitation needs to be overcome in securing the items and business value in starting a business.

• Convergence Security Journal
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• v.13 no.5
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• pp.187-196
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• 2013

Recently, school violence has come to the fore as a social phenomenon. "Comprehensive countermeasures for eradication of school violence" as a policy safety are created by Safety Administration bureau and Ministry of Education, Science and Technology under the chairmanship of the Office of Prime Minister on Feb,2012. This policy is supposed to be test-operated for a year from March, 2012. but voices of concern about effectiveness have been brought up by some critics greatly. So 172 teachers in high school in Seoul were surveyed in order to examine the effectiveness of "Comprehensive countermeasures for eradication of school violence" with a questionnaire composed of 5 point Likert-type. Among the fundamental measures, there were a total of 12 countermeasures about 'Practices for personality education' (with the exception of unrelated one question). 'Expanding opportunities of various art education and Supporting reading activities' of them ranked highest on average. Then, 'Reflecting results of special feature related to character develops to the Selection of Admission officers and Self-directed learning was the next. And among the three countermeasures about 'Reinforcement of roles of the family and society', 'Pan governmental conducting annual campaign related to broadcast, press, civic group to combat school violence was highest. Finally, among the 7 countermeasures about 'Countermeasure about harmful factors of games and internet addiction', 'Reinforcement of preventive discipline about game and internet addiction' was highest and 'Development and Promotion of various educational contents for preventive discipline about game and internet addiction' was the next.

• Journal of Korean society of Dental Hygiene
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• v.10 no.2
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• pp.283-295
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• 2010

Objectives : It surveyed the recognition level of oral health in class teachers who have influence of students' oral health knowledges and behaviors in our country, developed a program available for supplementing reinforcement in school oral health education, and planned the knowledge contents necessary for school oral health education hereafter. Methods : To arrange the basic data necessary for school oral health program, it carried out questionnaire survey by personal self-administration targeting 460 teachers for 19 elementary schools where are located in Jinhae city from May 7, 2007 to June 13. The following conclusions were obtained. Results : 1. The path of acquiring oral health knowledge was shown the high frequency with 23.9% and 23.3%, respectively, through publicity brochure and dental clinic. As for the opinion about the aim of maintaining dental hygiene, the prevention of dental caries was the highest with 53.7%. 2. The opinion about which the regular visit to the dentist is very effective for preventing dental caries accounted for 56.7%. The opinions about which the limit to sugar intake and the use of dental floss are effective for preventing dental caries accounted for 52.2% and 46.3%, respectively. 3. The opinion about which the fluoridation beverage intake and the sealant are effective for preventing dental caries accounted for 33.9% and 33.0%, respectively. 4. The opinion about which the regular toothbrushing without toothpaste has a little effect and has no effect on preventing dental caries accounted for 42.6% and 38.5%, respectively. Conclusions : The elementary-school age period, which is the most core field out of the whole oral health, is the important period that is formed the basis of lifelong oral health care. It surveyed the recognition level of oral health in class teachers who are in charge of direct health care while making continuous life with students, and developed program available for supplementing reinforcement in school oral health education. Through this, there will be necessity for cultivating ability available for properly managing oral health for the whole life by allowing elementary-school students, who will be led to future adults' oral health, to be formed the attitudes toward the rationally oral health care.

• Composites Research
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• v.13 no.6
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• pp.1-8
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• 2000

The fabrication Process of $Al_2O_{3p}$/AC8A composites by pressureless infiltration technique and the effects of additive Mg content and volume fraction of particulate reinforcement on mechanical and wear properties were investigated. It was found that the bending strength decreased with increasing volume fraction of $Al_2O_{3p}$ particles. Whereas hardness increased with volume fraction of $Al_2O_{3p}$ particles. The decrement of strength in case of high volume fraction of $Al_2O_{3p}$ particles was attributed to high porosity level. In terms of additive Mg content, $Al_2O_{3p}$/AC8A composites containing around 5~7wt% of additive Mg indicated the highest strength, and hardness values increased with additive Mg contents. Wear resistance of AC8A alloy were improved by reinforcement of $Al_2O_{3p}$ particles especially at high sliding velocity. Wear property of $Al_2O_{3p}$/AC8A composites and AC8A alloy exhibited different aspects. $Al_2O_{3p}$/AC8A composites indicated more wear loss than AC8A alloy at slow velocity region. However a transition point of wear loss was found at middle velocity region which shows the minimum wear loss and wear loss at high velocity region exhibited almost same value as at slow velocity region, whereas wear loss of AC8A alloy almost linearly increased with sliding velocity. It was found that $Al_2O_{3p}$/AC8A composites containing $Al_2O_{3p}$ volume fraction of 20% exhibited abrasive wear surface regardless of sliding velocity and $Al_2O_{3p}$/AC8A composites containing $Al_2O_{3p}$ volume fraction of 40% showed slightly adhesive wear surface at low sliding velocity, and it progressed to severe wear as increasing the sliding velocity.

• Advances in concrete construction
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• v.10 no.2
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• pp.171-183
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• 2020

The main objective of this study is the assessment of the ability of limestone mortars to resist to different chemical attacks. The ability of polypropylene (PP) fibres waste used as reinforcement of these concrete materials to enhance their durability is also studied. Crushed sand 0/2 mm which is a fine limestone residue obtained by the crushing of natural rocks in aggregates industry is used for the fabrication of the mortar. The fibres used, which are obtained from the waste of domestic plastic sweeps' fabrication, have a length of 20 mm and a diameter ranging between 0.38 and 0.51 mm. Two weight fibres contents are used, 0.5 and 1%. The durability tests carried out in this investigation included the water absorption by capillarity, the mass variation, the flexural and the compressive strengths of the mortar specimens immersed for 366 days in 5% sodium chloride, 5% magnesium sulphate and 5% sulphuric acid solutions. A mineralogical analysis by X-ray diffraction (XRD) and a visual inspection are used for a better examination of the quality of tested mortars and for better interpretation of their behaviour in different solutions. The results indicate that the reinforcement of limestone mortar by PP fibres waste is an excellent solution to improve its chemical resistance and durability. Moreover, the presence of PP fibres waste does not affect significantly the water absorption by capillarity of mortar nether its mass variation, when exposed to chloride and sulphate solutions. While in sulphuric acid, the mass loss is higher with the presence of PP fibres waste, especially after an exposure of 180 days. The results reveal that these fibres have a considerable effect of the flexural and the compressive behaviour of mortar especially in acid solution, where a reduction of strength loss is observed. The mineralogical analysis confirms the good behaviour of mortar immersed in sulphate and chloride solutions; and shows that more gypsum is formed in mortar exposed to acid environment causing its rapid degradation. The visual observation reveals that only samples exposed to acid attack during 366 days have showed a surface damage extending over a depth of approximately 300 ㎛.

• Korean Journal of Culture and Social Issue
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• v.28 no.2
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• pp.83-106
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• 2022

The current study examined the effects of the type and context of self-talk on task performance, task-post emotion, and perceived stress. Participants were 100 undergraduates in Busan. Participants were randomly assigned to one of four the experimental groups that were set by combining the narrative condition (the first-person versus non-first-person) to the content condition (self-reinforcing versus self-critic) to measure their pre and post intervention responses. For the analysis, we performed two-ways analysis of variance using the difference value of dependent variables comparing the pre and post-intervention. As a result of the analysis, we found that content condition of self-talk significantly influenced task performance, task-related confidence, emotion response, and perceived stress. That is, the self-reinforcement self-talk group showed better performance, higher task-related confidence, more positive emotion, lower negative emotion and less perceived stress than the self-critic self-talk group. The contents conditions of self-talk interacted with the narrative condition of self-talk to predict perceived stress, indicating that only non-first person/self-reinforceing self-talk group showed reduced levels of perceived stress.

• The Journal of Korean Society for School & Community Health Education
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• v.6
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• pp.89-107
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• 2005

The purposes of this study were to investigate the recognition and the needs and problems of in-service education for school nurse, and to suggest the desirable guidelines, for supples the basic data of in-service education for school nurse to upgraded the quality as school nurse's professional specialist. The subjects of this study were 376 school nurses who were working in Jollanamdo. The research instruments used in this study was 'Needs of In-service Education questionnaire'. 305 collected Data were analyzed with the frequency analysis, $x^2$-test. The conclusions were as follows; First of all, the most important motives for the school nurses to participate in-service education are the enhancement of their specialties on teaching profession, self-realizations as educators, and improvement of health teaching skill. However, the motives to obtain the skill for school management or to obtain a high rank qualification and promotion are quite low. School nurses are generally satisfied with duration, time, place of in-service education, But they are not satisfied with contents of in-service education, professional specialist and understanding of real educational situation of the instructors. On the urgent problem of school nurses, promotion of health teaching skill was highest in the rank, and establishment of firm educational philosophy and a sense of teaching profession, proceed to university and graduate school ranked next, respectively. Second, the need of a school nurses on in-service education direction ranked the application of teachers' character and need, practicable and concrete educational programs, planning of school health development, reinforcement of health education, expansion of practical knowledge and on reflection thought, respectively. The need of a school nurses on in-service education contents(major part) ranked health education, health promoting program of student, knowledge and practice of practical medicine and oriental medicine, consultation process, health education of advanced country, respectively. The need of in-service education supervisory organization, the need for a cities provinces educational office was highest in the rank. The need of in-service education type, duty training ranked high, and abroad training, qualification training, general training ranked next. the need for specialist for lecturer of in-serve education ranked among the highest, along with school nurses and university professor. The need of school nurses on education method(duplication answer), need for conference and discussion teaching was highest in the rank. The need on evaluation method, evaluation through a examination ranked the highest. On the needs of in-service education times, need for vacation during the winter and summer was the highest. As for the duration, 31 to 60 hours in duration of in-service education was need most, and most school nurses need cities and provinces in-service training institute as the location of in-service education. On the organization size, need for 21 to 30 people was the highest, where as need for 41 people was relatively low. Lastly, on the problem of in-service education for school nurses, lack of opportunity of in-service education for school nurses was highest in the rank, and improperness of in-service education contents and method, lack of incentive ranked next, respectively.

• The Journal of the Korea Contents Association
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• v.21 no.12
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• pp.202-216
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• 2021

Since the first 12 ones were designated in 1969, 228 places have been designated as tourism sites, and about 70 percent of them were designated before the 2000s. It shows that changes in most of tourism sites are needed in terms of physical, functional and environmental aspects. However, there are still not enough academic progress and policy consideration regarding the decline of tourism sites and the regeneration of them. This study aims to find the causes of decline and the factors to activate in tourism sites, to draw important conditions to recover the attractiveness of tourism sites in decline from the comprehensive analysis of causes and factors, and to apply the conditions to a real case in severely declining stage. According to the findings, the conditions for recovery could be restructured into four categories: 'The upgrade of hardware such as facilities in tourism site', 'the development of software such as contents and programs', 'the reinforcement of local capacity and institutional grounds' and 'the expansion of functions and the building of networks with various external stakeholders such as expert groups, related enterprises, talented individuals and so forth.