• Clean Technology
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• v.5 no.1
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• pp.49-61
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• 1999

Fenton's oxidation can improve the biodegradability of refractory organic wastewater by generating $OH{\cdot}$ which is one of the most reactive species. Fenton's reagent is used to treat a variety of industrial waste containing a range of toxic organic compounds. But this process cannot be economical because of high chemical cost of $H_2O_2$, ferrous ion solution and high sludge disposal cost. In this study, we proposed a modified Fenton's oxidation process which can reduce the reagent cost and obtain better removal efficiencies with less Fenton's reagents, and have a good potential of sludge recycling. In modified Fenton reaction, ferrous ion solution is adjusted to optimal pH with NaOH. Then it added to the sample and reacted to $H_2O_2$. For the experiment, synthetic wastewater made of phenol, which is one of the typical water pollutants, was used and the ionic strength of this wastewater was controlled by adding $NaHCO_3$. The effects of DO, ionic strength, and $H_2O_2$ dosing methods were investigated. As a result, modified Fenton's treatment efficiencies are better than conventional Fenton's reaction treating leachate and dyeing wastewater. And modified Fenton's treatment efficiencies combined to the sludge recycling for a half of Iron dosage are as good as the conventional Fenton's for a normal Iron dosage.

• Journal of Korean Society of Forest Science
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• v.104 no.4
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• pp.549-557
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• 2015

Novel cpSSR primers were developed based on the sequence information of the Pinus koraiensis chloroplast genome. A total of 30 cpSSR loci were detected in the chloroplast genome, and a total of 30 primer sets flanking those loci were designed. All primer sets were successfully amplified for chloroplast DNA in P. koraiensis. The cross-species transferability of the 30 primer sets was considerably high in P. pumila (100%) and P. paviflora (97%) belonging to the same Subgenus (Strobus) of P. koraiensis. Meanwhile, the transferability was relatively low (73%) in P. densiflora and P. sylvestris belonging to Subgenus Pinus. A total of 13 cpSSR loci out of the 30 loci were polymorphic in the Mt. Jumbong population of P. koraiensis. The mean of haploid diversity(H) was 0.512. The number of haplotypes(N) and the haplotype diversity($H_e$) were 25 and 0.992, respectively. Of the 25 haplotypes, 22 were unique in the analyzed population. The unique haplotypes differentiated 22 individuals (79%) from the total of 28 individuals. In conclusion, the novel cpSSR primers developed in this study would be applicable to other Pinus species, especially the subgenus Strobus, and provide a high level of polymorphism for the study of genetic variation of P. koraiensis.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.3
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• pp.39-49
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• 2017

Standards suitable for local conditions on deciding one-way road are desperately required to solve traffic congestions at the backside roads in the old downtown areas which were not designated as a road by urban planning. Therefore, this study intends to re-establish a standard to decide one-way road which is regarded to be of the greatest effect among traffic system control methods in order to control one-way road system more efficiently. Also, this paper suggests a standard for such decision to improve efficiency of using backside roads and expand designation of one-way road. AHP (analytic hierarchy process) was carried out among the traffic experts to find out the factors to decide one-way road system. Its result reveals that importance of causing accident to walking quantity and traffic was high. 10,000 cases out of all the possible scenarios of accident by combining detailed evaluation items and scales were extracted to draw the outcomes of analyzing the scenarios, which were schematized in a graph. As a result, division by three sections of point of inflection was verified into $1{\leq}$ section A<1.91, 1.9$1{\leq}$ section B<2.08, and $2.08{\leq}$ section C<3. In other words, priority of deciding one-way road should be given to section C, the highest total point, while posterior to section A, where relatively low points are distributed. The standard on deciding one-way road suggested in this paper may be used for designating one-way road and basic data to re-establish the relevant system in the future.

• Journal of The Korean Association For Science Education
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• v.34 no.4
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• pp.393-406
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• 2014

Pedagogical Content Knowledge (PCK) is intrinsically domain/topic-specific knowledge for teachers' expertise. On the basis of this idea about PCK, we investigated in-service science teachers' topic-specific PCK on the unit of stars and universe in terms of teachers' knowledge and practices. We observed four middle school science teachers' classes for eighth graders, and took the videos of the classes. The topics of the classes covered constellation, annual parallax and the distance of stars, and the expansion of the universe. We also examined the teachers' pedagogical thinking through video stimulated recall interviews. In addition, we developed a protocol to analyze the levels of participant teachers' PCK and the characteristics revealed in their classes on each topic. Results of the study showed that the participant teachers' level of PCK varied across the topics of classes and the sub-components of PCK. We also identified teaching orientations played key roles in shaping overall characteristics of their PCK. Moreover, astronomical thinking such as spatial thinking and system thinking, was not appropriately embedded as the specific practices into the astronomical concepts in their instructions. We discussed the implications on the progressions of teachers' PCK in terms of their professional development.

• Sleep Medicine and Psychophysiology
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• v.19 no.2
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• pp.89-96
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• 2012

Objectives: Individuals differ in their biological rhythms. This study investigated the association between the morningness-eveningness and sleep patterns, daytime sleepiness and fatigue in Korean male adolescents. Methods: Participants were 501 eleventh grade male students ($16.9{\pm}0.2$ years of age) in one male high school in Seoul. Each student completed the Korean translation of composite scale (KtCS), Epworth sleepiness scale (ESS), Fatigue Severity Scale (FSS) and a questionnaire about their sleep schedule. Results: The evening group had shorter weekday sleep time than the intermediate (p<0.001) or morning group (p=0.029). The evening group had more daytime napping (16.8%, p<0.001), high rate of caffeine use (58.8%, p<0.001) and snoring (18.5%, p=0.037). The evening group showed more daytime sleepiness (8.7, SD=3.2, p<0.001) and severe fatigue (4.4, SD=1.2, p<0.001) than the intermediate or morning group. Conclusion: Adolescents with eveningness have higher problems in weekday sleep, daytime sleepiness and fatigue. An intervention program for sleep problem in these adolescents should be considered.

• The KIPS Transactions:PartD
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• v.11D no.3
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• pp.709-716
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• 2004

This paper describes an intelligent real-time monitoring system of a semiconductor processing equipment, which determines normal or not for a wafer in processing, using multiple time-series pattern recognition. The proposed system consists of three phases, initialization, learning and real-time prediction. The initialization phase sets the weights and tile effective steps for all parameters of a monitoring equipment. The learning phase clusters time series patterns, which are producted and fathered for processing wafers by the equipment, using LBG algorithm. Each pattern has an ACI which is measured by a tester at the end of a process The real-time prediction phase corresponds a time series entered by real-time with the clustered patterns using Dynamic Time Warping, and finds the best matched pattern. Then it calculates a predicted ACI from a combination of the ACI, the difference and the weights. Finally it determines Spec in or out for the wafer. The proposed system is tested on the data acquired from etching device. The results show that the error between the estimated ACI and the actual measurement ACI is remarkably reduced according to the number of learning increases.

• Composites Research
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• v.29 no.1
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• pp.1-6
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• 2016

Low-speed impact was localized on a stiffened composite structure, using 4 FBG sensors with 100 kHz-sampling rate interrogator and devised localization algorithm. The composite specimen consists of a main spar and several stringers, and the overall size of the specimen's surface is about $0.8{\times}1.2m$. Pre-stored reference data for 247 grid locations and 36 stiffener locations are gathered and used as comparison target for a random impact signal. The proposed algorithm uses the normalized cross-correlation method to compare the similarities of the two signals; the correlation results for each sensor's signal are multiplied by others, enabling mutual compensation. 20 verification points were successfully localized with a maximum error of 43.4 mm and an average error of 17.0 mm. For the same experimental setup, the performance of the proposed method is evaluated by reducing the number of sensors. It is revealed that the mutual compensation between the sensors is most effective in the case of a two sensor combination. For the sensor combination of FBG #1 and #2, the maximum localization error was 42.5 mm, with average error of 17.4 mm.

• Korean Journal of Environment and Ecology
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• v.25 no.4
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• pp.470-478
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• 2011

Aster altaicus var. uchiyamae is on the list of endangered species in Korea. Using amplified fragment length polymorphism (AFLP) markers, we investigated the genetic diversity within and among four populations (Guram, Dori Island, Samhap, and Danyang) of A. altaicus var. uchiyamae. We also present the collecting strategies that most efficiently capture the genetic diversity of A. altaicus var. uchiyamae. Four AFLP primer combinations produced a total of 936 bands, of which 934 (99.8%) were polymorphic. A high level of genetic diversity (PPB = 45.3%, h = 0.104, I = 0.168, hs = 0.108) was recognized within the populations of A. altaicus var. uchiyamae. A low degree of genetic differentiation ($G_{ST}$ = 0.075, ${\theta}^B$ = 0.079) was detected among the populations. In addition, analysis of molecular variance (AMOVA) showed that genetic variation was greater within populations (91%) than among populations (9%). These results indicate that the high rate of gene flow has played an important role in forming the present populations of A. altaicus var. uchiyamae. According to maximization strategy, 17, 16, and 11 individuals captured all of the genetic variation in Dori Island, Samhap, and Guram population, respectively. The determination the minimum population size of A. altaicus var. uchiyamae in terms of the genetic information is critical and thereby gain reliable decision support for ex situ conservation of the endangered species, A. altaicus var. uchiyamae.

• Journal of Korea Water Resources Association
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• v.48 no.2
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• pp.79-90
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• 2015

In this study, the water quality parameters of Geum-river were estimated using Landsat 8 satellite image data which had launched in March 2013. The goal of this research is to predict HAB and to monitor spatial pattern of total nitrogen (TN) and total phosphorus (TP) because both TN and TP are the dominant factors of the growth of harmful algal blooms (HABs). To investigate the relationship between satellite band reflectance and in situ measurement value, Pearson' correlation coefficient analysis was used. The band2, 3, 4 and 5 reflectance values among 11 bands of Landsat 8 were used which was highly associated with detecting TN and TP. The 20 in situ data set with satellite's overpass time were identified. TN showed positive relation with band 2 (0.48), band3 (0.62), band4 (0.57) at a significance level of p<0.05. TP also showed high correlation for band2 (0.59), band3 (0.59), band4 (0.58) at a significance level of p<0.01. The optimal regression equation models were constructed for TN and TP based on multiple regression equations. The estimated concentration based on derived regression equations of TN and TP were compared with in situ measurement data. Finally, the spatial pattern of the two parameters was able be monitored through mapping on November 12, 2013 and April 21, 2014.

• Journal of the HCI Society of Korea
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• v.13 no.3
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• pp.17-33
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• 2018

Humans process aesthetic functions of objects such as form, size, color, and texture through vision, while at the same time observe them with a symbolic function by a new psychological interpretation based on their past experience. Therefore, it is more important to study and understand the thoughts and psychological influences of how humans perceive with their eyes than what humans simply look with them. With this research purpose in the background, this study will demonstrate in detail the cognitive characteristics of analog and digital images as a symbolic function with a "formative" point of view. Five hypotheses were established, which were proven through the following tests: smartphone, most frequently used in our daily lives, is simplified to a two-dimensional line drawing form, which is set to instances where the R(radius) is applied to the horizontal line of the two-dimensional form of smartphone, where Run-in-R(radius) is applied, and R(radius) rounding is applied to the edges of those shapes. The shapes were combined to form 12 pairs, which was used in a test to the test subjects. As a result, some human characteristics were observed; in specific, some helped prove objectively how humans perceived analog and digital images as psychologically stronger as a symbolic function. If people's thoughts and feelings gained through such study could be stored in database as one value and be provided to product designers, I believe it could be developed into design form as a basic emotional design that consumers desire.