• Journal of Korean Society of Water and Wastewater
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• v.32 no.1
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• pp.11-18
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• 2018

As the sequencing batch reactor process is a time-oriented system, it has advantages of the flexibility in operation for the biological nutrient removal. Because the sequencing batch reactor is operated in a batch system, respiration rate is more sensitive and obvious than in a continuous system. The variation of respiration rate in the process well represented the characteristics of biological reactions, especially nitrification. The respiration rate dropped rapidly and greatly with the completion of nitrification, and the maximum respiration rate of nitrification showed the activity of nitrifiers. This study suggested a strategy to control the aeration of the sequencing batch reactor based on respirometry. Aeration time of the optimal aerobic period required for nitrification was daily adjusted according to the dynamics of respiration rate. The aeration time was mainly correlated with influent nitrogen loadings. The anoxic period was extended through aeration control facilitating a longer endogenous denitrification reaction time. By respirometric aeration control in the sequencing batch reactor, energy saving and process performance improvement could be achieved.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.1061-1064
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• 2008

A completion of settling process takes a lot of time for dredged materials of high moisture content, such as contaminated sludge, in landfill site. In general, additives (e.g. flocculants) are used for reducing settling time of such colloidal material, which results in the increase of sludge volume, and hence much space is required in landfill site. This study is to suggest alternative method in order to enhance the settling process of cohesive clayey soils. A number of gravitational sedimentation tests as well as electrokinetic experiments were conducted to investigate the variation of initial moisture content on the settling behaviour of clay slurry. Surface settlement, electric current and local voltage gradient were monitored during the experiment, and moisture content and soil pH were measured after the experiment. From the results, the application of electrokinetics was found to be effective in volume reduction (i.e. increase of settling velocity and decrease of final moisture content) by comparison with gravitational settling process.

• Journal of Korean Association for Spatial Structures
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• v.20 no.3
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• pp.91-98
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• 2020

For form stability of membrane structures, membrane material is required to be in tension. Therefore, in planning and maintenance management, the engineer should consider enough about introduction of stress during construction and re-introduction of stress after completion. Clamping part is an important portion with the function for introducing tension into membrane materials, and the function to transmit stress to boundary structures, such as steel frames. Then, the purpose of this research is to clarify stress condition and stress transfer mechanism including clamping part of membrane structures, and to grasp the changing tendency of membrane structures with the passage of time. In this research, following previous one, we perform well-balanced evaluation by conducting tensile fractured tests of clamping part's specimens, and by measuring individually the amount of displacement of not only overall specimen's length but membrane material and clamping part. Thereby, we consider the influence the difference in the hardness of edge rope and the difference in the direction of thread affect modification and fracture load.

• Physical Therapy Korea
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• v.25 no.1
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• pp.53-61
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• 2018

Background: The process of language translation, adaptation, and cross-cultural validation of tools for use in multiple countries requires the adoption of well-established, comprehensive, and rigorous methodological approaches. Back translation, which is the most recommended method, permits the detection of errors in the translation and the identification of words or phrases that cannot be accurately or literally translated. Objects: The aim of this study was to verify the content validity of a Korean version of a Balance Evaluation Systems test (BESTest) by using a back-translation method. Methods: This research was conducted in six steps: 1) translation of the BESTest into Korean, 2) evaluation of the translation conformity of Korean-translated BESTest, 3) evaluation of the degree of translation comprehension, 4) back translation of Korean BESTest, 5) evaluation of the technical and conceptual equivalence, and 6) completion of the Korean version of BESTest by the translation verification committee. Results: In this study, Korean version of the BESTest achieved a rating of more than 3 (moderate) for translation comprehension, and technical equivalence and conceptual equivalence of back translation were evaluated as 3 (moderate) or more. Conclusion: The Korean version of the BESTest has proven content validity and is an appropriate tool to measure balance function.

• Korean Journal of Health Education and Promotion
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• v.13 no.2
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• pp.115-129
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• 1996

This study was designed to provide the material for the development of policies for the improvement of the quality of life the elderly by identifying the relationship among general characteristics, mental health, physical health and social health which exert an effect on the improvement of the quality of old people’s lives, development of a model capable of enhancing the quality of life for the elderly and establishing the future direction of health education. 1000 old people who were more than 60 years old were selected as subjects for this study, and the interview and inquire methods using the questionnaire and the self-completion method were employed to obtain data. 1. It was shown that there was a significant difference between the home elderly and Institutionalized elderly in terms of all measured items except stress item of general characteristic, as well as on almost measured items of physical health, mental health and social health, and it was shown that there was the interaction between departments. 2. Since it was shown that general characteristics, mental health, physical and social health were interrelated, it can be seen that one characteristic is mutually related to other characteristics.

• Journal of the Korean Society of Fashion and Beauty
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• v.6 no.1
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• pp.53-59
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• 2008

This study focused on the expression technique and work manufacturing of nail design. Any woman that wants to be pretty is interested in nail design which is considered as a means to express beauty, intelligence and sensuality. These days, nail design carries heavy weight in completion of total fashion coordination. Good dress, elegant hair style, bright make-up and well-trimmed nails are requirements of modem women. These days, the range of nail design is more expanding and its importance is getting bigger. To maintain and establish such developmental flow properly, we have to break our stereotyped view on nails and accept it in open view. And we have to actively participate in development of new products and technologies and perform academic research on nail design. For the purpose, we have to consider further studies which contribute to understanding exact meaning of nails and necessity and importance of nails.

• Korean Medical Education Review
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• v.17 no.2
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• pp.57-59
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• 2015

Student research has been proposed as an educational strategy to fulfill the current requirements in basic medical education (BME) and to compatible with the self-directed development of professionalism. It is commonly accepted that the goals of student research are to develop the competencies of critical, reflective, and self-directed thinking; problem-solving; and creativity; as well as to acquire the skills necessary to search for information and analyze the literature; to cultivate the talent of mastering a specialized field through deeply intensified learning; and to establish close relationships between students and supervisors. To successfully implement student research, authorities on BME should to plan the procedure for the student research projects and allocate personal and material resources adequately in order to provide the opportunity for self-evaluation and reflection through the completion of daily records, to develop the habit of consistently evaluating one's own study, and to maintain a collegial relationship between students and supervisors by offering the proper feedbacks in a timely and consistent manner. In conclusion, despite several obstacles and difficulties in the establishment of successful student research projects, student research could provide students the motivation to develop themselves into expert academic researchers, and play a role in educating students to help solve patients' problems based on scientific evidence in the future.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.3
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• pp.243-249
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• 2015

In direct vehicle teleoperation, a human operator drives a vehicle at a distance through a pair of master and slave device. However, if there is time delay, it is difficult to remotely drive the vehicle due to slow response. In order to address this problem, we introduced a novel methodology of shared vehicle teleoperation using a virtual driving interface. The methodology was developed with four components: 1) virtual driving environment, 2) interface for virtual driving environment, 3) path generator based on virtual driving trajectory, 4) path following controller. Experimental results showed the effectiveness of the proposed approach in simple and cluttered driving environment as well. In the experiments, we compared two sampling methods, fixed sampling time and user defined instant, and finally merged method showed best remote driving performance in term of completion time and number of collision.

• English Language & Literature Teaching
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• v.12 no.2
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• pp.215-235
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• 2006

This paper explores the effects of two different methods of instruction for 106 low-level Korean learners of English at a college in learning request expressions. Both of the methods contained the focus-on-form and function characteristics, while the degree of explicitness for input enhancement was differentiated. Abundant email samples written by English native speakers for the input were provided and email writing practice for the output was proceeded for both groups of the students in the treatment sessions. The numbers of target forms used in pretest and posttest results were compared quantitatively: The tests included email writing and open-ended Discourse Completion Test (DCT). The results indicated that the target pragmatic features were slightly better learned under the condition of relatively high degree of explicit instruction with metapragmatic information, even though the difference was statistically insignificant. In addition, the students' use of request strategies both in email and DCT was affected positively by the treatment with email input and output. That is, the students applied the request strategies they learned through email into their oral production (open-ended DCT) as well as their email writing. Further study on the output effect of target features in advancing pragmatic competence is suggested.

• Korean Journal of Organic Agriculture
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• v.25 no.4
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• pp.861-873
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• 2017

The present study was conducted to investigate the developmental characteristics of Propylea japonica Thunberg (Coleoptera : Coccinellidae), a predator of aphids under laboratory conditions. The development times of the egg and immature stages of Propylea japonica were investigated at ten constant temperatures(15, 17.5, 20, 22.5, 25, 27.5, 30, 32.5, 35 and $38{\pm}1^{\circ}C$; 14L:10D; $60{\pm}5%$ RH). Development time was longest at $17.5^{\circ}C$. The developmental periods of P. japonica from the time of egg oviposited to adult emergence was 36.9 days at $17.5^{\circ}C$, and it decreased ash temperature increasing. Threshold temperature of development and degree days of the P. japonica from egg to adult were $11.9^{\circ}C$ and 196.0 respectively. The Briere 2 and Lactin 2 modes were best fitted for all development stages. The distribution of completion of each development stage was explain relatively well that 2-parameter, 3-parameter and Logistic model except egg and pupal stage.