• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.2
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• pp.10-19
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• 2019

Management plan with repairing is essential for RC structures exposed to chloride attack since durability problems occur with extended service life. Conventionally deterministic method is adopted for evaluation of service life and repair cost, however more reasonable repair cost can be obtained through continuous repair cost from probabilistic maintenance technique. Unlike the previous researches considering only normal distribution of life time, PLTFs (Probabilistic Life Time Function) which can be capable of handling log and normal distributions are attempted for initial and repair service life, and repair cost is evaluated for OPC and GGBFS concrete. PLTF with log distributions in initial service life is more effective to save repair cost since it is more dominant after average than normal distribution. Repair cost in GGBFS concrete decreases to 30% of OPC concrete due to longer initial service life and lower repairing event. The proposed PLTF from the work can handle not only normal distributions but also log distributions for initial and repair service life, so that it can provide more reasonable repair cost evaluation.

• Journal of Forest and Environmental Science
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• v.34 no.6
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• pp.461-471
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• 2018

In this study, the deforestation and forest degradation areas have been obtained in Myanmar using a land cover lamp (LCM) and a tree cover map (TCM) to get the $CO_2$ potential reduction and the strength of occurrence was evaluated by using the geostatistical technique. By applying a multiple criteria decision-making method to the regions having high strength of occurrence for the $CO_2$ potential reduction for the deforestation and forest degradation areas, the priority was selected for candidate lands for REDD+ project. The areas of deforestation and forest degradation were 609,690ha and 43,515ha each from 2010 to 2015. By township, Mong Kung had the highest among the area of deforestation with 3,069ha while Thlangtlang had the highest in the area of forest degradation with 9,213 ha. The number of $CO_2$ potential reduction hotspot areas among the deforestation areas was 15, taking up the $CO_2$ potential reduction of 192,000 ton in average, which is 6 times higher than that of all target areas. Especially, the township of Hsipaw inside the Shan region had a $CO_2$ potential reduction of about 772,000 tons, the largest reduction potential among the hotpot areas. There were many $CO_2$ potential reduction hot spot areas among the forest degradation area in the eastern part of the target region and has the $CO_2$ potential reduction of 1,164,000 tons, which was 27 times higher than that of the total area. AHP importance analysis showed that the topographic characteristic was 0.41 (0.40 for height from surface, 0.29 for the slope and 0.31 for the distance from water area) while the geographical characteristic was 0.59 (0.56 for the distance from road, 0.56 for the distance from settlement area and 0.19 for the distance from Capital). Yawunghwe, Kalaw, and Hsi Hseng were selected as the preferred locations for the REDD+ candidate region for the deforestation area while Einme, Tiddim, and Falam were selected as the preferred locations for the forest degradation area.

• Phonetics and Speech Sciences
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• v.13 no.3
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• pp.79-90
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• 2021

This single-subject study examined the effects of repetitive speech training at the word and sentence levels using speech cues on the percentage of correct consonants (PCC) and speech intelligibility of children with cerebral palsy (CP). Three children aged between 5-8 years with a history of CP participated in the study. Thirty-minute intervention sessions were provided four times a week for four weeks. The intervention included repeated training of words and sentences containing target phonemes using two instructions of speech cues, "big mouse" and "strong voice". First, the children improved their average PCC and speech intelligibility, but an effect size analysis indicated that the effect was different for each child, and the effect size for speech intelligibility was higher than for PCC. Second, the intervention effect was generalized to untrained words and sentences. Third, the maintenance effects of PCC and speech intelligibility were very high. These findings suggests that repeated speech training using speech cues is an intervention technique that can help improve PCC and speech intelligibility in children with CP.

• Journal of Apiculture
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• v.32 no.3
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• pp.155-162
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• 2017

This research was carried out to evaluate the royal jelly production in Apis mellifera through the selection of superior honeybee lines. For the study, two inbred honeybee lines A and C were evaluated for the production of royal jelly by their workers, royal jelly production per colony (g), and the acceptance percentage of grafted larvae (%). The results showed that, the average royal jelly production per colony was highest ($33.7{\pm}7.41g$) in the inbred line C in comparison to other lines and the percentage of larvae acceptance ($87.8{\pm}7.5%$) was also highest in the inbred line C in comparison to other liens. The royal jelly produced by the three honeybee lines was analyzed for their trans-10-hydroxy-2-decenoic acid (10-HDA) content using a column liquid chromatography technique. Chromatographic results showed that the royal jelly produced by the inbred honeybee line C had the maximum amount of 10-HDA. We also observed age-dependent alterations of the major royal jelly proteins (MRJPs), which were differentially expressed in the two inbred lines and the commercial line, using quantitative real time-PCR (qRT-PCR).

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.3
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• pp.57-67
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• 2021

A thorough administration of the arterial road network requires a continuous supply of updated and accurate information about the traffic that travels on the roads. One of the ways to effectively obtain the traffic volume and weight distribution of heavy vehicles is the BWIM technique, which is actively being studied. Unlike previous studies, this study was performed to develop a simplified Bridge Weigh-In-Motion (BWIM) algorithm that can easily estimate the axle spacing and weight of a traveling vehicle by utilizing the structural characteristics of the bridge. A short span RC T-beam bridge with no crossbeam installed was selected for the study, and then the strain response characteristics of bridge deck and girder was checked through preliminary field test. Based on the preliminary field test results, a simplified BWIM algorithm suitable for the bridge to be studied was derived. The validity and accuracy of the BWIM algorithm derived in this study were verified through field test. As a result of the verification test, the proposed BWIM algorithm can estimate the axle spacing and gross weight of the travelling vehicles with the average percent error of less than 3%.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.1
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• pp.13-24
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• 2021

Tunnel boring machine (TBM) is widely used for tunnel excavation in hard rock and soft ground. In the perspective of TBM-based tunneling, one of the main challenges is to drive the machine optimally according to varying geological conditions, which could significantly lead to saving highly expensive costs by reducing the total operation time. Generally, drilling investigations are conducted to survey the geological ground before the TBM tunneling. However, it is difficult to provide the precise ground information over the whole tunnel path to operators because it acquires insufficient samples around the path sparsely and irregularly. To overcome this issue, in this study, we proposed a geological type classification system using the TBM operating data recorded in a 5 s sampling rate. We first categorized the various geological conditions (here, we limit to granite) as three geological types (i.e., rock, soil, and mixed type). Then, we applied the preprocessing methods including outlier rejection, normalization, and extracting input features, etc. We adopted a deep neural network (DNN), which has 6 hidden layers, to classify the geological types based on TBM operating data. We evaluated the classification system using the 10-fold cross-validation. Average classification accuracy presents the 75.4% (here, the total number of data were 388,639 samples). Our experimental results still need to improve accuracy but show that geology information classification technique based on TBM operating data could be utilized in the real environment to complement the sparse ground information.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.333-339
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• 2020

Pheromone-based techniques are becoming a viable strategy of insect pest management as facilitated by the exponential increase in numbers of pheromone identifications from many insect pests. This is the report on the efficacy of pheromone-mediated chemical communication disruption (PCD) technique against the Korean population of smaller clearwing moths, Synanthedon tenuis (Butler) (Lepidoptera: Sesiidae) using its female sex pheromone component, (Z, Z)-3, 13-octadecadien-1-ol. The PCD trials were carried out four times during 2016 and 2017 in persimmon orchards located at Suncheon and Jinju Cities in Korea, and the PCD efficacy was expressed as the mean differences in the seasonal catches of S. tenuis males in the PCD and control plots. The seasonal male moth catches in monitoring traps installed in the PCD plots were significantly lower as compared with those installed in the control plots. Consequently, the PCD efficacy in the experimental orchards ranged from 95.2-100% with an average efficacy of 98.8 ± 1.2%, revealing a future possibility of pheromone-based management of S. tenuis.

• The Journal of the Korea Contents Association
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• v.21 no.5
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• pp.234-246
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• 2021

The purpose of this study is to develop the main subjects of the job-based curriculum by deriving the job analysis results of general security job workers in the physical protection field responsible for responding to threats to nuclear materials and nuclear facilities. In the job analysis stage, FGI was conducted on 7 content experts to derive 8 duties and 55 tasks. In addition, knowledge and skills were drawn for each task. In the analysis of educational needs, surveys were conducted for workers in general security jobs to derive the top 25 educational priorities through t-test and Borich needs assess model. At the stage of selecting core tasks and organizing required/optional contents, 42 tasks, both above average or at least one of them, were derived as core tasks based on the result of evaluation of importance and difficulty ratings of 55 tasks through a questionaire. In addition, tasks applied to the top 25 rankings derived from Borich needs assess model were applied as the required contents when designing courses, and tasks which applied only one of them were selected as optional contents. At the stage of required/optional modules and educational contents, four required modules and five optional modules were derived by drifting similar tasks between the required and optional contents. Based on the above results, the study suggested academic and practical implications and future suggestions.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.6
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• pp.655-662
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• 2021

This study aimed to estimate exploitable groundwater for the sustainable supply of groundwater in the Jinju region of South Gyeongsang Province. As an integrated hydrologic analysis model, SWAT-MODFLOW was used to estimate the distributed groundwater recharge in consideration of land use and soil distribution. As a result of calibration of the model, the coefficient of determination between the observed flow and the simulated flow was 0.75-0.80, which was good. The simulated groundwater recharge rate showed a spatio-temporal distribution due to heterogeneous watershed characteristics. The amount of groundwater recharge shows lower values over winter and spring, but it increases according to the pattern of precipitation in summer and autumn. The calculated average annual groundwater recharge was compared with the result using the baseflow separation method of natural flow, and the deviation of both results was small, within 3 %, confirming the validity of the estimated groundwater recharge. Exploitable groundwater is defined as the amount of recharge corresponding to low flow with 10 years of return period. Therefore, in this study, 14.2 % of the annual precipitation was found to be exploitable as a result of calculating the amount of recharge at a 10-year frequency using a statistical frequency analysis technique.

• Journal of the Korea Society of Computer and Information
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• v.27 no.7
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• pp.115-124
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• 2022

The purpose of this study is to analyze and present keywords, trends, and language networks of keywords for each year of the pedagogical exam of the secondary teacher's employment exam for the 2019~2022 school year. The main research methods were text mining technique and language network analysis method, and analysis programs were KrKwic, Wordcloud Maker, Ucinet6, NetDraw, etc. The research results are as follows; First, keywords such as teacher, student, curriculum, class, and evaluation appeared in the top rankings, and keywords (online, wiki, discussion ceremony, information, etc.) that reflect the recent online class progress in the current COVID-19 situation also tended to appear. The keywords with high frequency of occurrence in the four-year integrated text were student(44), teacher(39), class(27), school(18), curriculum(16), online(10), and discussion method(8). Second, the overall language network of the keywords with high frequency of 4 years showed a significant level of density(0.566), total number of links(492), and average degree of links(16.4). The degree centrality was found in the order of teacher(199.0), class(197.0), student(185.0), and school(150.0). Betweenness centrality was found in the order of teacher(30.859), class(18.956), student(16.054), and school (15.745). It is expected that the results of this study will serve as data to be considered for preparatory teachers, institutions and related persons, and teachers and administrators of secondary school teacher training institutions.