• Journal of the Korea Concrete Institute
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• v.24 no.3
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• pp.333-340
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• 2012

The current study prepared 9 laboratorial concrete mixes and 3 ready-mixed concrete batches to examine the size and shape effects in compression failure of lightweight aggregate concrete (LWC). The concrete mixes were classified into three groups: normal-weight, all-lightweight and sand-lightweight concrete groups. For each concrete mix, the aspect ratio of circular or square specimens was 1.0 and 2.0. The lateral dimension of specimens varied between 50 and 150 mm for each laboratorial concrete mix, whereas it ranged from 50 to 400 mm with an incremental variation of 50 mm for each ready-mixed concrete batch. Test observations revealed that the crack propagation and width of the localized failure zone developed in lightweight concrete specimens were considerably different than those of normal-weight concrete (NWC). In LWC specimens, the cracks mainly passed through the coarse aggregate particles and the crack distribution performance was very poor. As a result, a stronger size effect was developed in LWC than in NWC. Especially, this trend was more notable in specimens with aspect ratio of 2.0 than in specimens with that of 1.0. The prediction model derived by Kim et al. overestimated the size effect of LWC when lateral dimension of specimen is above 150 mm. On the other hand, the modification factors specified in ASTM and CEB-FIP provisions, which are used to compensate for the shape effect of specimen on compressive strength, were still conservative in LWC.

• Journal of Service Research and Studies
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• v.10 no.2
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• pp.77-89
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• 2020

This study analyzed the effect of Servant Leadership on leader trust and job engagement for the lower-level leader in airline crew occupations with the aim of identifying the possibility of establishing the theoretical framework of Servant Leadership in the service industry. As a result of the regression analysis, it was found that the social learning dimension of Servant Leadership has greater influence than the social exchange dimension on the leader trust, while the influence on job engagement is the opposite. The results of this analysis can be interpreted that trying to learn the words and actions of the Servant Leader is more effective in further consolidating the trust of the subordinates in the leader. On the other hand, the Servant Leader's words and actions for social exchange are inferred to have more influence on the job engagement. This study is targeted at air transport services, exposing limitations to the generalization of research results. Throughout leadership research and organizational research, including Servant leadership, further studies applying the social learning theory and social exchange theory presented in this paper are expected to produce theoretical results that will lead to the emergence of a new framework for research analysis.

• Journal of The Korean Association For Science Education
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• v.33 no.1
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• pp.17-29
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• 2013

High school 'science' in the 2009 revised curriculum in Korea was developed for the purpose of enhancing students' scientific literacy needed for citizenship in a democratic society. For this analysis, 'science' includes a variety of scientific topics from the origin of the universe to the birth of life, and the relationship between technology and modern society. It aims to make students understand the process of scientific inquiry and foster interest and curiosity about science. On the other hand, interest has been studied as a psychological construct to affect academic achievement and career selection of students. In this study, the authors investigated students' interest in high school 'science' in view of the 2009 revised curriculum. To carry this out, a survey tool was developed according to previous research, with 997 high school students' responses analyzed with descriptive statistics and factor analysis. The result showed that the students' interest in high school 'science' in view of the 2009 revised curriculum can be interpreted into three dimensions such as motivation, activity, and topic, which has several sub-dimensions. Students' interest in motivation dimension was higher than in activity or topic dimension, while the average value was slightly higher than the middle value. They showed different distribution of interest by gender and job orientation, especially in activity and topic dimensions. From this study, the authors can infer the multi-dimensional property of students' interest in high school 'Science' and the different distribution of interest by dimensions.

• Korean Journal of Social Welfare Studies
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• v.44 no.2
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• pp.465-497
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• 2013

This paper criticizes the ontological and epistemological dichotomy in social sciences including social welfare and probes into Critical Realism as an alternative paradigm. Many theories for social welfare have adhered to dichotomous ontological standpoint, 'agency' vs. 'social structure', and Eco-system approach have occupied dominant position to integrate this dichotomy. These theoretical standpoint have had great influence on social work practice. On the other hand, dichotomous epistemological standpoint which is constituted of different views of phenomena, 'positivism' and 'constructionism', have had great influence on social work research and practice. These dichotomous ontological and epistemological approach have a limit to reveal qualitative nature of the relationship between agency and social structure, to ponder the deeper reality, the mechanism of stratified reality, and the reality being independent of agency. Replacing these approaches, Critical Realism unfold the theoretical potential as an alternative paradigm for social welfare through the discussion on stratified realty(the empirical, the actual, and the real), intransitive/transitive dimension, double hermeneutics in these dimensions, and the conditions for conceptualization, duality of structure and practice, transformation model of agency and structure.

• Tunnel and Underground Space
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• v.29 no.4
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• pp.243-261
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• 2019

Microseismic monitoring technologies have been recognized for its superiority over traditional methods and are used in domestic and overseas underground mines. However, the complex gangway layout of underground mines in Korea and the mixed structure of excavated space and rock masses make it difficult to estimate the microseismic propagation and to determine the arrival time of microseismic wave. In this paper, experimental studies were carried out to determine the source location according to various arrival picking methods and dimensional conditions. The arrival picking methods used were FTC (First Threshold Cross), Picking window, AIC (Akaike Information Criterion), and 2-D and 3-D source generation experiments were performed, respectively, under the 2-D sensor array. In each experiment, source location algorithm used iterative method and genetic algorithm. The iterative method was effective when the sensor array and source generation were the same dimension, but it was not suitable to apply when the source generation was higher dimension. On the other hand, in case of source location using RCGA, the higher dimensional source location could be determined, but it took longer time to calculate. The accuracy of the arrival picking methods differed according to the source location algorithms, but picking window method showed high accuracy in overall.

• Journal of the Korean Society of Food Culture
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• v.23 no.5
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• pp.582-594
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• 2008

This study aimed at evaluating current sanitation management performances in Korean-Food restaurants by their operation types and to develop sanitary training posters based on the risk factors, in an attempt to improve the level of sanitation management in Korean food service facilities. Eighteen Korean-food restaurants that are managed by franchisor, franchisees as well as self-managed with large-scale and small-scale restaurants in Seoul and Gyeonggi-Do, were evaluated by on-the-spot inspectors with an auditing tool consisting of three dimensions, nine categories and thirty four items. Data were analyzed using SPSS. The total score of each group showed that restaurants managed by franchisees ranked the highest (59 out of 100 points), while self-managed, small-scale restaurants ranked the lowest (44 out of 100 points). In the categorization of sanitation management compliance, the dimensions of food hygiene during production recorded the lowest compliance rate of 47.7% (22.89/48.0 points) followed by the dimension of environmental hygiene 59.3% (20.17/34.0 points) and personal hygiene 60.5% (10.89/18.0 points). This indicated the need for urgent improvement. The items which showed the lowest compliance rates were 'proper thawing of frozen foods' (0%), 'notifying and observing heating/reheating temperature' (6%), 'using of hand-washing facility and proper hand-washing' (33%), 'monitoring temperature of frozen-foods and cold-foods' (35%), and 'prevention of cross-contamination' (36%) among thirty four items. Self-managed, small-scale restaurants, in particular, needed to improve sanitary practices such as 'sanitation education for employee', 'verifying the employee health inspection reports', 'storing food on the shelves 15 cm distance away from the wall', 'suitability of ventilation capacity of hoods' and 'cleanliness of drainage'. On the basis of the findings of this study, we developed sanitary training posters, especially for small-scale restaurant operators. This could be an effective tool to educate food service employees on sanitary knowledge and principles and could be used to improve the existing sanitary conditions in Korean food service facilities.

• Korean Journal of Applied Biomechanics
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• v.16 no.4
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• pp.39-47
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• 2006

This study long jump action to each situation on a chessboard and section of sight disabled person and normal person through third dimension reflex analysis mechanical special quality because do comparative analysis sight disabled person's exercise ability and technology structure of action that run understand. As can do better without danger of injury map and training of exercise item that action that run is included, do offer of pabulum by purpose. Through this study, conclusion is as following. 1. Sight disabled persons' long jump average recording (121.84cm) showing normal persons' average recording (259.27cm) and much differences, show that motion of body is not big to Touch-down from Ready action. 2. Each phase body center composition(r) average speed displayed result that it is more meaning more than Each phase time required. 3. Began in line carriage without body back stretching in 1 situation on Event one are sight disabled persons. Was expose that do not bend enough knee and ankle than normal person in Event two. Was expose that body is not drooped for surface of land in Event three, and knee and ankle were expose that do not unfold easily than normal person. Was expose that do not bend enough on Touch-down knee by relation that can not grasp position of the floor in Event four. 4. When taking off, the average of horizontal speed of body center are 1.80m/sec for blind people and 3.53m/sec for the normal. In this connection, the study shows that the difference of horizontal speed between the blind and the normal is bigger than difference of vertical speed, which are 1.56m/sec for the blind and 1.98m/sec for the normal. Also, composite speed also shows us big difference between 2.41m/sec of the blind and 4.07m/sec of the normal. The speed body center of take-off was expose that average adjuster are big width of deceleration than average - beginning disabled person's average by 2.23m/sec - 1.71m/sec in the vertical speed. 5. If examine change of high and low for z Sign of right hand, change of high and low showed as is small than normal person is sight obstacle, and all hand movements are small and was expose that do not use enough reaction of body as well as in ready action.

• Structural Engineering and Mechanics
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• v.49 no.4
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• pp.491-498
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• 2014

During the past years, the protection of the environment has become a major concern out passing the state frontiers to reach a planetary dimension. Depository waste sites have become a serious problem in terms of their locations and costs. On the other hand, the construction industry has a leading place in terms of quantities of waste produced from the start to the end of each construction site, by the large amounts of raw materials used and their respective consequences on the environment. The recycling of quarry wastes products, of demolished concrete, bricks and large quantities of waste resulting from the transformation of marble blocks can provide ideal solutions and advantages for the preservation of the environment, to become a supplementary source of aggregates. The main purpose of this study is to show technically the possibility of recuperating the aggregates of marble wastes as a partial substitute or total in the mortars. The aggregates used in this study is a sand of marble wastes (excess loads of sand exposed to bad weather conditions) of the quarry derived from Fil-fila marble (Skikda, east of Algeria). To achieve this work, we have studied the effect of sand substitution of marble wastes in the mortar with rates of (25, 50, 75, 100%); comparing the results obtained with reference samples (0%), the properties when the samples are fresh, and the mechanical performances of mortars at solid state (loss and gain of weight, dimensional variations). The introduction of recycled sand in the mortars gives good results and can be used as granulates.

• The Journal of Pediatrics of Korean Medicine
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• v.20 no.3
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• pp.33-50
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• 2006

Objectives : Oriental medicine has set the no herb medicamentous dose for child, on the other hand the western medicine has it standardizing of age, weight or dimension of body. Therefore, we aimed to research the herb medicamentous dose for child being in being used in clinic. Methods : We made up a question of the oriental medical doctors of the master's and doctor's course in ○○ university. Results : 1. Child dose of herb medicine a time likes this. 1 pack is written prescription most at children patients under 1 year. 1 pack and 2 packs are written prescription most at children patients over 1 under 2. 2 packs are written prescription most at children patients over 2 under 3. 4 packs are written prescription most at children patients over 3 under 4. 10 packs are written prescription most at children patients over 8 under 14. Dose of herb medicine written prescription at children patients over 5 under 8 is in decentralization from 2 to 10 packs. 2. 2 or 3 times are most in a number of taking medicine a day. 3. 3 days are common in period of taking medicine under 5, over 10 days are common over 5. 4. It is necessary to regulating child dose of herb medicine.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.3
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• pp.270-276
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• 2001

The treatment of mandibular subcondylar fractures is a matter of controversy. The majority of mandibular subcondylar fracture are treated by closed reduction, but the displaced or dislocated mandibular subcondylar fractures may be treated by open reduction. The characteristics of open reduction are the anatomical reduction, the functional restoration, the rapid function, the maintenance of vertical ramus dimension, the better appearance and the less resultant TMJ problem etc. When an open reduction is considered, the wire, miniplate, lag screw and Kirschner wire are available with internal fixation. Of these, Kirschner wire is a simple method relatively and correct positioning of the wire achieves rigid fixation. But many open reduction methods for mandibular subcondylar fractures require extraoral approach. The extraoral approach has some problems, the facial scar and the risk of facial nerve injury. On the other hand, the intraoral approach eliminates the potency of the facial scar and the facial nerve injury, but is difficult to access the operation site. Since the intraoral approach was first described by Silverman (1925), the intraoral approach to the mandibular condyle has been developed with modifications. The purpose of this article is to describe the intraoral technique with the Kirschner wire on mandibular subcondylar fractures. Conclusion : The intraoral reduction with Kirschner wire on mandubular subcondylar fractures avoids the facial scar and facial nerve injury and is simple method to the extraoral approach. And it has minimal morbidity and better esthetics.