• Journal of Korean Society of Water and Wastewater
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• v.29 no.3
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• pp.359-370
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• 2015

This study developed an up-flow wetland providing either an eco-friendly follow-up process of medium-sized public treatment facility for livestock manure or a non-point source pollution controller near livestock farms. The four bench-scale up-flow wetlands were operated with four different bed media sets. The removal efficiencies of the wetland effluent for CODCr, TN, TP, SS were 35.2 %, 29.5 %, 31.2 % and 52.2 % for set 1(Blank, without reed, with bio-ceramic), 40.6 %, 43.4 %, 42.2 % and 55.4 % for set 2(with bio-reed & without bio-ceramic), 45.2 %, 48.7 %, 46.6 % and 66.3 % for set 3(with bio-reed & bio-ceramic), 32.9 %, 27.3 %, 29.3 % and 54.1 % for Set 4(with reed & bio ceramic), respectively. The set 3 condition having a mixture of bio-reed and bio-ceramic showed the highest efficiency in the bench-scale evaluation. This study suggests a mixture of bio-reed and bio-ceramic as suitable bed media in the construction of artificial wetlands near livestock farms. Soils including the bed media were monitored during the evaluation for trace elements. Soil analysis results were satisfied with the Korean Soil Contamination Standard. This study showed that the up-flow constructed wetland was feasible to treat the effluent livestock wastewater treatment facility.

• Earthquakes and Structures
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• v.16 no.2
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• pp.197-208
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• 2019

The objective of this study is to propose new seismic intensity parameters based on the Hilbert spectrum and to associate them with the seismic damage potential. In recent years the assessment of even more seismic features derived from the seismic acceleration time-histories was associated with the structural damage. For a better insight into the complex seismic acceleration time-history, Hilbert-Huang Transform (HHT) analysis is utilized for its processing, and the Hilbert spectrum is obtained. New proposed seismic intensity parameters based on the Hilbert spectrum are derived. The aim is to achieve a significant estimation of the seismic damage potential on structures from the proposed new intensity parameters confirmed by statistical methods. Park-Ang overall structural damage index is used to describe the postseismic damage status of structures. Thus, a set of recorded seismic accelerograms from all over the word is applied on a reinforced concrete frame structure, and the Park-Ang indices through nonlinear dynamic analysis are provided and considered subsequently as reference numerical values. Conventional seismic parameters, with well-known seismic structural damage interrelation, are evaluated for the same set of excitations. Statistical procedures, namely correlation study and multilinear regression analysis, are applied on the set of the conventional parameters and the set of proposed new parameters separately, to confirm their interrelation with the seismic structural damage. The regression models are used for the evaluation of the structural damage indices for every set of parameters, respectively. The predicted numerical values of the structural damage indices evaluated from the two sets of seismic intensity parameters are inter-compared with the reference values. The numerical results confirm the ability of the proposed Hilbert spectrum based new seismic intensity parameters to approximate the postseismic structural damage with a smaller Standard Error of Estimation than this accomplished of the conventional ones.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.2
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• pp.41-46
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• 2011

Purpose: The result of exam using an imaging device is very closely related with the image quality. Moreover, this image quality can be changed according to the condition of image acquisition and evaluation method. In this study, we evaluated the image quality according to the difference of pre-set method in PET/CT image. Materials & Methods: PET/CT Discovery STe16 (GE Healthcare, Milwaukee, USA), Chest PET phantom (Experiment 1) and 94 NEMA phantom (Experiment 2) were used. Phantom were filled with $^{18}F$-FDG maintaining hot sphere and background ratio to 4:1. In the case of experiment 1, we set the radio activity concentration on 3.5, 6.0, 8.6 kBq/mL. In the case of experiment 2, we set the radio activity concentration on 3.3, 5.5, 7.7, 9.9, 12.1, 16.5 kBq/mL. All experiments were performed with the time-set method for 2 minutes 30 seconds per frame and the count-set method with one hundred million counts in 3D mode after CT transmission scan. For the evaluation of the image quality, we compared each results by using the NECR and SNR. Results: In the experiment 1, both the NECR and SNR were increased as radioactivity concentration getting increased. The NECR was shown as 53.7, 66.9, 91.4. and SNR was shown as 7.9, 10.0, 11.7. Both the NECR and SNR were increased in time-set method. But the count-set method's pattern was not similar with the time-set method. The NECR was shown as 53.8, 69.1, 97.8, and SNR was shown as 14.1, 14.7 14.4. The SNR was not increased in count-set method. In experiment 2, results of both the NECR and SNR were shown as 45.1, 70.6, 95.3, 115.6, 134.6, 162.2 and 7.1, 8.8, 10.6, 11.5, 12.7, 14.0. These results were shown similar patten with the experiment 1. Moreover, when the count-set method was applied, the NECR was shown as 42.1, 67.3, 92.1, 112.2, 130.7, 158.7, and SNR was shown as 15.2, 15.9, 15.6, 15.4, 15.5, 14.9. The NECR was increased but SNR was not shown same pattern. Conclusion: Increment of administered radioactivity improves the quality of image unconcerned with the pre-set method. However, NECR was not influenced by increment of total acquisition counts through simple increasing scan duration without increment of administered activity. In case of count-set method, the SNR was shown similar value despite of increment of radioactivity. So, the administered activity is more important than the scan duration. And we have to consider that evaluation of image quality using only SNR may not be appropriate.

• Environmental Engineering Research
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• v.15 no.3
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• pp.167-172
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• 2010

The effects of low impact development (LID) techniques, such as green roofs and porous pavements, on the runoff and pollutant load from an apartment complex were simulated using the Site Evaluation Tool (SET). The study site was the Olympic Village, a preexisting apartment complex in Seoul, South Korea, which has a high percentage of impervious surfaces (approximately 72% of the total area). Using the SET, the effects of replacing parking lots, sidewalks and driveways (37.5% of the total area) having porous pavements and rooftops (14.5% of the total area) with green roofs were simulated. The simulation results indicated that LID techniques reduced the surface runoff, and peak flow and pollutant load, and increased the evapotranspiration and soil infiltration of precipitation. Per unit area, the green roofs were better than the porous pavements at reducing the surface runoff and pollutant loads, while the porous pavements were better than green roofs at enhancing the infiltration to soil. This study showed that LID methods can be useful for urban stormwater management and that the SET is a useful tool for evaluating the effects of LID on urban hydrology and pollutant loads from various land covers.

• Journal of Korean Society of Water and Wastewater
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• v.24 no.6
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• pp.743-751
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• 2010

It requires an interim performance assessment for BTL business of the sewerage rehabilitation which continues from 2005 till now. Means, It is necessary to make an interim performance assessment and an analysis of an business effect of the sewerage rehabilitation BTL projects which still continues, and we presented an improvement method of the new sewerage rehabilitation project in future. This paper has conducted an analysis of the business effect for 3 local government BTL projects which are completed and under operation as of now in Jincheon-Gun, Cheongju-Si and Gangjin-Gun. As a method of business effect analysis, we conducted a business effect of the 3 places using the index set which we previously set for the business effect analysis. The index set in this research was sectionalized to an improvement effect of operating wastewater treatment plant, an benefit effect of the direct cost, an benefit effect of the indirect cost and an environment friendly effect. We, in this paper, conducted an business effect analysis for 3 sewerage rehabilitation BTL projects which are completed or under operation recently as a demonstration, however we judge that an business effect analysis shall be conducted in a stage that a significant time for operation has passed since the completion of the construction in order to induce an actual business effect of the sewerage rehabilitation BTL project.

• Proceedings of the Korean Society for Quality Management Conference
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• 2006.11a
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• pp.251-259
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• 2006

Evaluation of the work of art with intention of the artist different is not a possibility of free oneself from the limit which estimates an evaluation at value of appreciator. We tried new interpreting about the work of art in this paper. The work of art respects the intention of the artist to make it and interprets intention until now. After critics distinguish by a period, an area that they set to philosophical thought which is the time and interpreted. We set to each one subjectivity and interpreted between artist to make the work of art and appreciator. But in this paper, we tied various criteria which appreciates the work of art. We tried so that we presented the intimacy each other newly. Otherwise we tied with the subjectivity of the individual and are the try to be an objectification low through statistical technique. We looked into the culture and art in the introduction and explain the discussion about the work of art interpreting which the main subject. We set the category 6 area, and explain an each criteria explanation and assessment method. We tried to propose new interpreting as the intimacy to be multivariate data analysis result of the assessment analysis. Stopping from the thing which sees the work of art knows, it will be able to give meaning thing from this research prerequisite.

• Phonetics and Speech Sciences
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• v.3 no.1
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• pp.35-43
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• 2011

The purpose of this paper is to evaluate the viability of employing the intonation exaggeration technique proposed in [4] in teaching English prosody to university students. Fifty-six female university students, twenty-two in a control group and the other thirty-four in an experimental group, participated in a teaching experiment as part of their regular coursework for a five-and-a-half week period. For the study material of the experimental group, a set of utterances was synthesized whose intonation contours had been exaggerated whereas the control group was given the same set without any intonation modification. Recordings from both before and after the teaching experiment were made and one sentence set was chosen for analysis. The parameters analyzed were the pitch range, words containing the highest and lowest pitch points, and the 3-dimensional comparison of the three prosodic features [2]. An AXB and subjective rating test were also performed along with a qualitative screening of the individual intonation contours. The results showed that the experimental group performed slightly better in that their intonation contour was more similar to that of the model native speaker's utterance. This appears to suggest that the intonation exaggeration technique can be employed in teaching English prosody to students.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.5
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• pp.496-504
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• 2003

The purpose of this study was (1) to identify the experimental bias which could appear person perception as results of presentation methods (2) to find out the most desirable method in presentation of stimulus. The research was a quasi experiment and the subjects were 773 male and female undergraduate students. The experimental instruments consisted of a set of stimulus and semantic differential scales of 7- point hi-polar adjectives. The collected data were analyzed by Factor Analysis, ANOVA(analysis of variance), Scheffe＇s multiple range test. The independent variables were presentation orders and presentation time of stimulus. The results were as follows: First, five factors which were potency, sociality, appearance, evaluation, activity impression dimensions emerged to account for the methods of development of stimulus. Second, the presentation order of stimulus in the combination of four stimuli sets had significant effects on the 3 impressional factors(sociality, appearance, evaluation). The presentation order of stimuli in the combination of eight stimuli set had significant effects on the 3 impressional factors(potency, sociality, appearance) and the presentation order of stimuli in the combination of eight stimuli set showed a significant effect on memorization of stimulus and the results support the recency effect. Third, the presentation time of stimuli had significant effects on the 2 impressional factors(potency, activity). 30 seconds presentation as well as free duration time resulted less experimental bias than 3 seconds presentation.

• Journal of the Korean Society of Safety
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• v.26 no.4
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• pp.87-95
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• 2011

The urgent VAI(Vital Area Identification) method development is required since 'The Act of Physical Protection and Radiological Emergency' that is established in 2003 requires an evaluation of physical threats in nuclear facilities and an establishment of physical protection in Korea. The KAERI(Korea Atomic Energy Research Institute) has developed the VAI methodology and VAI software called as VIPEX(Vital area Identification Package EXpert) for identifying the vital areas. This study is to demonstrate the applicability of KAERI's VAI methodology to a hypothetical facility, and to identify the importance of information of cable and piping runs when identifying the vital areas. It is necessarily needed to consider cable and piping runs to determine the accurate and realistic TEPS(Top Event Prevention Set). If the information of cable and piping runs of a nuclear power plant is not considered when determining the TEPSs, it is absolutely impossible to acquire the complete TEPSs, and the results could be distorted by missing it. The VIPEX and FTREX(Fault Tree Reliability Evaluation eXpert) properly calculate MCSs and TEPSs using the fault tree model, and provide the most cost-effective method to save the VAI and physical protection costs.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.58 no.4
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• pp.359-366
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• 2022

In this study, the load fluctuation of the main engine is considered to be a disturbance for the jacket coolant temperature control system of the low-speed two-stroke main diesel engine on the ships. A nonlinear PID temperature control system with satisfactory disturbance rejection performance was designed by rapidly transmitting the load change value to the controller for following the reference set value. The feed-forwarded load fluctuation is considered the set points of the dual loop control system to be changed. Real-coded genetic algorithms were used as an optimization tool to tune the gains for the nonlinear PID controller. ITAE was used as an evaluation function for optimization. For the evaluation function, the engine jacket coolant outlet temperature was considered. As a result of simulating the proposed cascade nonlinear PID control system, it was confirmed that the disturbance caused by the load fluctuation was eliminated with satisfactory performance and that the changed set value was followed.