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Microbial community analysis of an eco-friendly recirculating aquaculture system for olive flounder (Paralichthys olivaceus) using complex microbial probiotics (복합미생물 프로바이오틱을 이용한 환경친화적 넙치 순환여과양식시스템에서의 미생물군집 분석)

  • Rhee, Chaeyoung;Kim, Haham;Emmanuel, S. Aalfin;Kim, Hong-Gi;Won, Seonghun;Bae, Jinho;Bai, Sungchul C.;Koh, Sung-Cheol
    • Korean Journal of Microbiology
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    • v.54 no.4
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    • pp.369-378
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    • 2018
  • This study was conducted to evaluate effects of dietary microbial probiotics on the growth and disease resistance of olive flounder (Paralichthys olivaceus) in a recirculating aquaculture system (RAS), and the effects of the probiotic bioaugmentation on the microbial community structure and water quality. For the analysis, 80 juvenile fish (average weight, $25.7{\pm}7.6g$; average length, $15.2{\pm}1.7cm$) were fed a basal diet containing a commercial microbial product CES-AQ1 (CES; $1{\times}10^9\;CFU/kg$ diet) in an RAS for 8 weeks. Weight gain, the specific growth rate, feed efficiency, and protein efficiency ratio of the fish fed the CES diet in the RAS were 1.5~2.5 times higher than those of fish fed the basal diet alone, or the basal diet containing oxytetracycline (OTC), yeast plus bacterium, or Bacillus subtilis in a still water system. There was no significant difference in the pathogen challenge test between fish fed the OTC diet and fish fed the CES diet in the RAS, suggesting the CES-AQ1 probiotic used in the RAS as a potential replacement for antibiotics. The RAS biofilter maintained the highest microbial diversity and appeared to harbor microbial communities with ammonium oxidation, denitrification, and fish pathogen suppression functions. Ammonia, which is hazardous to fish, was significantly decreased to < 0.5 mg/L in 19 days, indicating the effectiveness of probiotic supplementation to maintain good water quality in RAS. These results suggest that the intestinal microbial communities of fish are stabilized by a probiotic-containing diet (CES) and that bioaugmentation with probiotics may be an eco-friendly and economical supplement for aquaculture of olive flounder, promoting both good water quality and fish health in an RAS.

Numerical modeling of secondary flow behavior in a meandering channel with submerged vanes (잠긴수제가 설치된 만곡수로에서의 이차류 거동 수치모의)

  • Lee, Jung Seop;Park, Sang Deog;Choi, Cheol Hee;Paik, Joongcheol
    • Journal of Korea Water Resources Association
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    • v.52 no.10
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    • pp.743-752
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    • 2019
  • The flow in the meandering channel is characterized by the spiral motion of secondary currents that typically cause the erosion along the outer bank. Hydraulic structures, such as spur dike and groyne, are commonly installed on the channel bottom near the outer bank to mitigate the strength of secondary currents. This study is to investigate the effects of submerged vanes installed in a $90^{\circ}$ meandering channel on the development of secondary currents through three-dimensional numerical modeling using the hybrid RANS/LES method for turbulence and the volume of fluid method, based on OpenFOAM open source toolbox, for capturing the free surface at the Froude number of 0.43. We employ the second-order-accurate finite volume methods in the space and time for the numerical modeling and compare numerical results with experimental measurements for evaluating the numerical predictions. Numerical results show that the present simulations well reproduce the experimental measurements, in terms of the time-averaged streamwise velocity and secondary velocity vector fields in the bend with submerged vanes. The computed flow fields reveal that the streamwise velocity near the bed along the outer bank at the end section of bend dramatically decrease by one third of mean velocity after the installation of vanes, which support that submerged vanes mitigate the strength of primary secondary flow and are helpful for the channel stability along the outer bank. The flow between the top of vanes and the free surface accelerates and the maximum velocity of free surface flow near the flow impingement along the outer bank increases about 20% due to the installation of submerged vanes. Numerical solutions show the formations of the horseshoe vortices at the front of vanes and the lee wakes behind the vanes, which are responsible for strong local scour around vanes. Additional study on the shapes and arrangement of vanes is required for mitigate the local scour.

Development of nutrition quotient for elementary school children to evaluate dietary quality and eating behaviors (학령기 아동 대상 영양지수 개발과 타당도 검증)

  • Lee, Jung-Sug;Hwang, Ji-Yun;Kwon, Sehyug;Chung, Hae-Rang;Kwak, Tong-Kyung;Kang, Myung-Hee;Choi, Young-Sun;Kim, Hye-Young
    • Journal of Nutrition and Health
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    • v.53 no.6
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    • pp.629-647
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    • 2020
  • Purpose: This study was undertaken to develop a nutrition quotient for elementary school children (NQ-C) for evaluating the overall dietary quality and eating behaviors. Methods: The NQ-C was developed by implementing 3 stages: item generation, item reduction, and validation. Candidate food behavior checklist (FBC) items of the NQ-C were derived from systematic literature reviews, expert in-depth interviews, statistical analyses of the fifth Korean National Health and Nutrition Examination Survey data, and national nutrition policies and recommendations. For the pilot survey, 260 elementary school students (128 second graders and 132 fifth graders) completed self-administered questionnaires as well as 24-hour dietary intakes, with the help of their parents and survey team staff, if required. Based on the pilot survey results, expert reviews, and priorities of national nutrition policy and recommendations, checklist items were reduced from 41 to 24. A total of 20 items for NQ-C were finally selected from results generated from 1,144 nationwide samples surveyed. Construct validity of the NQ-C was assessed using the confirmatory factor analysis, LInear Structural RELations. Results: Analyses of the exploratory factors of NQ-C identified that 5 dimensions of diet (balance, diversity, moderation, practice and environment) accounted for 46.2% of the total variance. Standardized path coefficients were used as weights of the items. The NQ-C and 5-factor scores of the subjects were calculated using the obtained weights of the FBC items. Conclusion: Our data indicates that NQ-C is a useful and suitable instrument for assessing nutrition adequacy, dietary quality, and eating behaviors of Korean elementary school children.

Very short-term rainfall prediction based on radar image learning using deep neural network (심층신경망을 이용한 레이더 영상 학습 기반 초단시간 강우예측)

  • Yoon, Seongsim;Park, Heeseong;Shin, Hongjoon
    • Journal of Korea Water Resources Association
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    • v.53 no.12
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    • pp.1159-1172
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    • 2020
  • This study applied deep convolution neural network based on U-Net and SegNet using long period weather radar data to very short-term rainfall prediction. And the results were compared and evaluated with the translation model. For training and validation of deep neural network, Mt. Gwanak and Mt. Gwangdeoksan radar data were collected from 2010 to 2016 and converted to a gray-scale image file in an HDF5 format with a 1km spatial resolution. The deep neural network model was trained to predict precipitation after 10 minutes by using the four consecutive radar image data, and the recursive method of repeating forecasts was applied to carry out lead time 60 minutes with the pretrained deep neural network model. To evaluate the performance of deep neural network prediction model, 24 rain cases in 2017 were forecast for rainfall up to 60 minutes in advance. As a result of evaluating the predicted performance by calculating the mean absolute error (MAE) and critical success index (CSI) at the threshold of 0.1, 1, and 5 mm/hr, the deep neural network model showed better performance in the case of rainfall threshold of 0.1, 1 mm/hr in terms of MAE, and showed better performance than the translation model for lead time 50 minutes in terms of CSI. In particular, although the deep neural network prediction model performed generally better than the translation model for weak rainfall of 5 mm/hr or less, the deep neural network prediction model had limitations in predicting distinct precipitation characteristics of high intensity as a result of the evaluation of threshold of 5 mm/hr. The longer lead time, the spatial smoothness increase with lead time thereby reducing the accuracy of rainfall prediction The translation model turned out to be superior in predicting the exceedance of higher intensity thresholds (> 5 mm/hr) because it preserves distinct precipitation characteristics, but the rainfall position tends to shift incorrectly. This study are expected to be helpful for the improvement of radar rainfall prediction model using deep neural networks in the future. In addition, the massive weather radar data established in this study will be provided through open repositories for future use in subsequent studies.

The Computer Monitor's Image Evaluated at The Target of The Falsification According to The New Conception of The Falsification Made by Regarding the Reproduced Document as The Document of Document crime (복사문서의 문서간주가 창출한 새로운 변조개념에 의해 문서변조행위대상으로 평가되는 컴퓨터모니터 이미지)

  • Ryu, Seok-Jun
    • Journal of Legislation Research
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    • no.44
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    • pp.725-756
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    • 2013
  • In this paper, the possibility of extension of falsification conception was investigated to discuss the validity of this precedent. Consequently this extension was indispensible according to the article 237-2 of criminal code which regards the reproduced document as the document in the document crime. However, this is against the security of human right. On the contrary, there is not this kind of article in the German criminal code and the German precedents and majority theory are negative to regard it as the criminal document. And also, there is the pont of view that the reproduced document is not the criminal document because it's not the expression itself of document nominee's intention, so the article 237-2 should be demolished in Korea. According to this opinion, the serious reconsideration should be required in the legislation of this article 237-2. Nevertheless, if this extended conception is needed and it's possible, the meaning of the computer monitor's image is not able to be ignored in the conception of falsification. Therefore this should be regarded as the element of the falsification conception. In other words, this can't be evaluated as the object of falsification but the target of falsification, according to the conception extension, though the precedents do not regard it as the document in document crime.

Effect of Summer Sea Level Rise on Storm Surge Analysis (하계 해수면 상승이 폭풍해일고 분석에 미치는 영향)

  • Kim, A Jeong;Lee, Myeong Hee;Suh, Seung Won
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.33 no.6
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    • pp.298-307
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    • 2021
  • Typhoons occur intensively between July and October, and the sea level is the highest during this time. In particular, the mean sea level in summer in Korea is higher than the annual mean sea level about 14.5cm in the west coast, 9.0 to 14.5cm in the south coast, and about 9.0 cm in the east coast. When the rising the sea level and a large typhoon overlap in summer, it can cause surges and flooding in low-lying coastal areas. Therefore, accurate calculation of the surge height is essential when designing coastal structures and assessing stability in order to reduce coastal hazards on the lowlands. In this study, the typhoon surge heights considering the summer mean sea level rise (SH_m) was calculated, and the validity of the analysis of abnormal phenomena was reviewed by comparing it with the existing surge height considering the annual mean sea level (SH_a). As a result of the re-analyzed study of typhoon surge heights for BOLAVEN (SANBA), which influenced in August and September during the summer sea level rise periods, yielded the differences of surge heights (cm) between SH_a and SH_m 7.8~24.5 (23.6~34.5) for the directly affected zone of south-west (south-east) coasts, while for the indirect southeast (south-west) coasts showed -1.0~0.0 (8.3~12.2), respectively. Whilst the differences between SH_a and SH_m of typhoons CHABA (KONG-REY) occurred in October showed remarkably lessened values as 5.2~ 14.2 (19.8~21.6) for the directly affected south-east coasts and 3.2~6.3 (-3.2~3.7) for the indirectly influenced west coast, respectively. The results show the SH_a does not take into account the increased summer mean sea level, so it is evaluated that it is overestimated compared to the surge height that occurs during an actual typhoon. Therefore, it is judged that it is necessary to re-discuss the feasibility of the surge height standard design based on the existing annual mean sea level, along with the accurate establishment of the concept of surge height.

A Study for operation results of the comprehensive examination on tendering system in the cultural heritage repair and restoration, focusing on the cause of the decline in the winning bid rate (문화재수리 종합심사낙찰제·종합평가낙찰제 운영결과 및 낙찰률하락 원인 분석)

  • JUNG, Younghun;YUN, Hyundo
    • Korean Journal of Heritage: History & Science
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    • v.55 no.1
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    • pp.111-132
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    • 2022
  • The comprehensive examination on tendering system has been introduced to the Cultural Heritage repair and restoration field since 2016 to remedy the repair issues of South Gate in 2014. The Cultural Heritage Administration tried to attain the high performance of the cultural heritage repair and restoration works securing the proper payment for the repair and restoration works. It is high time to review the operating performance of the comprehensive examination on tendering system (hereinafter referred to as the "CEOTS"), as the system has been run for over 5 years to correspond with its original goal, i.e., "The Proper Payment in return for the High Performance of Repair and Restoration works." This study intends to analyze 114 tenders of CEOTS from 2016 to 2020. As a result of the analysis of 114 tenders, firstly, more than half of bid winners were in the top 20% of repair & restoration capacity disclosure amount list, which mostly fulfilled the goal of 'attaining high performance.' Secondly, as the winning bid rate is decreasing from 86.847% in 2017 to 85.488% in 2020, the goal of 'guarantee of a proper payment' is not achieved yet. Thirdly, the influence of Economic Evaluation section in CEOTS has been grown since the change of scoring system in CEOTS in 2019. This study identifies two reasons why the winning bid rate of CEOTS has decreased. Firstly, it is caused by the fact that 'the group that got more than 1st place' and 'the first place group' that are more than half of the total bidders have the decreasing bidding rate trend as the years go by. Secondly, the exclusion rate of 'the group that got more than 1st place' is higher than the exclusion rate of 'the group that got less than 1st place', which means the expected winning rate would be lowered. It is proposed that the revision of CEOTS code is needed, i.e. easing the strict rule concerning the exclusion rate as well as setting up the lower bidding limit to prevent the excessive decreasing winning bid rate.

The impact of functional brain change by transcranial direct current stimulation effects concerning circadian rhythm and chronotype (일주기 리듬과 일주기 유형이 경두개 직류전기자극에 의한 뇌기능 변화에 미치는 영향 탐색)

  • Jung, Dawoon;Yoo, Soomin;Lee, Hyunsoo;Han, Sanghoon
    • Korean Journal of Cognitive Science
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    • v.33 no.1
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    • pp.51-75
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    • 2022
  • Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation that is able to alter neuronal activity in particular brain regions. Many studies have researched how tDCS modulates neuronal activity and reorganizes neural networks. However it is difficult to conclude the effect of brain stimulation because the studies are heterogeneous with respect to the stimulation parameter as well as individual difference. It is not fully in agreement with the effects of brain stimulation. In particular few studies have researched the reason of variability of brain stimulation in response to time so far. The study investigated individual variability of brain stimulation based on circadian rhythm and chronotype. Participants were divided into two groups which are morning type and evening type. The experiment was conducted by Zoom meeting which is video meeting programs. Participants were sent experiment tool which are Muse(EEG device), tdcs device, cell phone and cell phone holder after manuals for experimental equipment were explained. Participants were required to make a phone in frount of a camera so that experimenter can monitor online EEG data. Two participants who was difficult to use experimental devices experimented in a laboratory setting where experimenter set up devices. For all participants the accuracy of 98% was achieved by SVM using leave one out cross validation in classification in the the effects of morning stimulation and the evening stimulation. For morning type, the accuracy of 92% and 96% was achieved in classification in the morning stimulation and the evening stimulation. For evening type, it was 94% accuracy in classification for the effect of brain stimulation in the morning and the evening. Feature importance was different both in classification in the morning stimulation and the evening stimulation for morning type and evening type. Results indicated that the effect of brain stimulation can be explained with brain state and trait. Our study results noted that the tDCS protocol for target state is manipulated by individual differences as well as target state.

Analysis of Fire Occurrence Characteristics According to Ignition Heat Sources (발화열원에 따른 화재발생 특성 분석)

  • Lee, Kyung-Su;Kim, Tae-Hyeung;Lee, Jae-Ou
    • Journal of the Society of Disaster Information
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    • v.18 no.2
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    • pp.280-289
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    • 2022
  • Purpose: In this study, the characteristics of fire occurrence according to ignition heat sources such as operating equipment, cigarette/lighter fire, and flame/fire were analyzed. Method: One-way ANOVA and cross-analysis were used to analyze the characteristics of fire occurrence by verifying the difference between the ignition environment, fire damage status and scale, and cause of ignition according to the ignition heat source. Result: The fire occurrence characteristics were analyzed through As a result of the analysis, it was found that fires caused by operating devices occurred more frequently on weekdays than other ignition heat sources, and the number of victims and the number of victims were the highest, so mobilization of firefighting power and property damage were the greatest. The initial ignition was generated by electric and electronic devices, and the combustion was expanded by the synthetic resin. For fires caused by cigarette and lighter fires, the most fires occurred on Saturdays and Sundays, and the mobilization of the police force was more characteristic than the mobilization of the firefighting force. In particular, it was found that the initial ignition and combustion expansion were caused by paper, wood, and hay. Fires caused by sparks and sparks occurred most frequently on Saturdays and Sundays, and initial ignition and combustion expansion were found to be caused by paper, wood, and hay. In particular, it showed the characteristic that it occurred in the place farthest from the fire station. The common characteristic of all ignition heat sources was that the fire occurred most frequently in the afternoon time, and the fire type was predominantly the building structure fire, and only the ignition point was burned the most. Conclusion: In order to prevent fire and minimize damage, it is necessary to analyze the tendency of fire occurrence and to prepare appropriate preparations according to the fire occurrence factors. In order to analyze the characteristics of fire occurrence using public data in the future, it is necessary to standardize disaster data and to open and activate data.

Soon Chul Jung's Melody Development Technique from the Viewpoint of Motive Unit Analysis (모티브(Motive) 단위 분석 관점으로 바라본 정순철 동요의 선율 전개기법)

  • Son, Mi-Jin;Chung, Jae-Youn
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.2
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    • pp.35-46
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    • 2021
  • The purpose of this research is to analyze Soon Chul Jung's children's songs, who is one of the four great children's songwriters in Korea along with Geuk Young Yoon, Nan Pa Hong and Tae Jun Park. Soon Chul Jung has contributed by actively participate into children's movement at Japanese colonial period through writing self-composed children's songs. Since children's songs are made for the age group without the sense of sound, children's songs necessitate 'easy to sing-along' melody writing process. Like so, when writing the melody that are easy to be sang along, utilization of development technique using a unit called motive can be the potent way. This method has an advantage of being sang more with ease if actively implemented, and can be done by utilizing the smallest unit of the melody called motive, especially by lightly transform and repeat the unit, consequently structuring the song altogether. To investigate and analyze this motive-based development technique of Soon Chul Jung's songs, 38 out of 40 written songs considered eligible for the research were confirmed and chosen from 'Soon Chul Jung's bibliography and choreography' and each songs were analyzed based on 17 different development techniques which were standardized in the textbook 'Melody in Songwriting' adopted as a textbook of the Berklee college of Music, and also compared these song-writing pipelines with other great songwriters' representatives mentioned above. As a result, it was almost linear that the song's pitch variation in combination with thinning or extension were used frequently and repeatedly, otherwise implicating melody duplication for more than 2 bars and motive repetition were not in his favor, while these methods were often used when writing children's songs. This finding could be viewed as a character of his songwriting.