• Journal of Korea Water Resources Association
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• v.53 no.6
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• pp.395-408
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• 2020

This paper aims to develop and apply three different machine learning approaches (i.e., artificial neural networks (ANN), adaptive neuro-fuzzy inference systems (ANFIS), and wavelet-based neural networks (WNN)) combined with an evolutionary optimization algorithm and the k-fold cross validation for multi-step (days) streamflow forecasting at the catchment located in Algeria, North Africa. The ANN and ANFIS models yielded similar performances, based on four different statistical indices (i.e., root mean squared error (RMSE), Nash-Sutcliffe efficiency (NSE), correlation coefficient (R), and peak flow criteria (PFC)) for training and testing phases. The values of RMSE and PFC for the WNN model (e.g., RMSE = 8.590 ㎥/sec, PFC = 0.252 for (t+1) day, testing phase) were lower than those of ANN (e.g., RMSE = 19.120 ㎥/sec, PFC = 0.446 for (t+1) day, testing phase) and ANFIS (e.g., RMSE = 18.520 ㎥/sec, PFC = 0.444 for (t+1) day, testing phase) models, while the values of NSE and R for WNN model were higher than those of ANNs and ANFIS models. Therefore, the new approach can be a robust tool for multi-step (days) streamflow forecasting in the Seybous River, Algeria.

• Korean Journal of Microbiology
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• v.44 no.4
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• pp.271-276
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• 2008

Ribosome stalling by nascent sticky peptide has been reported in several organisms across the kingdom. To test whether small subunit (SSU) rRNA is involved in this phenomenon, we developed a genetic system that utilized the specialized ribosome system to isolate SSU rRNA mutants that enable ribosomes to bypass the SecM-derived sticky peptide in protein synthesis. In this system, CAT-SecM mRNA, which encodes CAT protein containing the sticky peptide derived from SecM, is only translated by specialized ribosomes. These ribosomes were shown to transiently stall on CAT-SecM mRNA followed by the synthesis of the sticky peptide. Expression of specialized ribosomes resulted in the decreased steady-state level of CAT-SecM mRNA, which is consistent with a notion that ribosome stalling induces mRNA degradation. Isolation and characterization of SSU rRNA mutations using this genetic system that are sufficient to circumvent ribosome stalling induced by the SecM-derived sticky peptide will provide evidence of SSU rRNA function in mRNA cleavage.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.21-21
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• 2012

수송용 산업의 하나인 국내 조선업계는 2008년 말 이후 세계 조선경기 불황 속에서도 2009년 451억달러, 2010년 491억달러의 사상최대 수출액을 달성한 바가 있고 세계 조선사 순위에서는 1위에서 5위까지 한국 조선소 등이 우위를 차지하고 있다. 그러나 개별 기업 경쟁력은 우위에 서있지만 중국과의 격차가 많이 좁혀지고 있어 안심할 수 없는 상황이다. 특히 최근에는 탄소배출량이 적은 친환경 선박의 제조가 선박업계 전반의 화두로 대두되고 있다. 이를 위해 다양한 시도가 시도되고 있는데 그중에 하나가 선박의 경량화이다. 금속외장 전선은 선박 무게의 10~13%를 차지하고 있고 전체 사용 전선의 30~40%를 차지하고 있어 선박에서의 금속외장 전선의 무게를 줄이기 위한 연구가 필요한 실정이다. 또한 조선산업 뿐만 아니라 자동차 분야에서도 금속 외장전선이 많이 사용되고 있으며, 자동차의 연비 향상을 위한 경량화 연구가 더욱 절실한 상황이다. 본 연구에서는 수송용으로 사용되는 전선의 금속외장을 경량 고강도 섬유를 활용한 하이브리드 wire로 대체하기 위한 편조 기술 및 편조 장치를 개발하기 위한 설계 및 기초연구를 수행하였다. 초경량 고강도 섬유 Armor의 제조기술 및 최적 공정 개발을 위한 연구로서 경쟁사 샘플에 대한 분석을 실시하였고, 사용된 섬유의 성분 분석 및 물성시험을 수행하였다. 또한 원형직기 개발을 위한 구조부 설계를 위해 ANSYS해석을 수행하고 저신율 고강도인 아라미드의 이징모션 시스템 개발을 위한 연구를 수행하였으며 개구 형성방법을 설계하였다. 그리고 초경량 고강도 hybrid 케이블 아라미드 편조 표면 및 내부 가교에 의한 가공 기술을 연구하였다. 아라미드 섬유의 발수성 향상을 위한 코팅재료 선정을 위한 연구를 수행하였고, 자외선 경화공정에서 조건별 데이터를 정립하여 솔루션을 제공하고자 한다.

• Journal of Life Science
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• v.14 no.5
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• pp.840-846
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• 2004

A study for expression of Korean Mistletoe (KM) lectin gene (A,B) in Saccharomyces cerevisiae was done using transforming system of yeast. In order to overexpress the genes efficiently in yeast, two lectin genes (A,B) were re-cloned and modified including Kozak translation initiation sequence using PCR amplification. The constructed plasmids containing modified lectin A and B genes were transformed to S. cerevisea INVSc (MAT G, his3 $\Delta$1, leu2, trpl-289, ura3-52). The transformed cells were identified by DNA sequencing with ABI3700 system and induced with 2% of galactose for recombinant KM lectin (rKM lectin) protein. The rKM lectin A and B proteins were determinated about 29kDa size of protein by SOS-P AGE and western blotting analysis. The expressed recombinant lectin was determinated 1.24∼1.75 $\mu\textrm{g}$ per 1 mg of cytosolic soluble protein by sandwich ELISA method. Moreover the lectin genes were expressed as maximum level at 36 h after galactose induction and lectin A gene was were repressed after 48 h.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.8
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• pp.521-529
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• 2017

Three-dimensional flow characteristics within a high-acceleration first-stage turbine vane passage has been investigated in a newly-built vane cascade for propulsion. The result shows that there is a strong favorable pressure gradient on the vane pressure surface. On its suction surface, however, there exists not only a much stronger favorable pressure gradient than that on the pressure surface upstream of the mid-chord but also a subsequent adverse pressure gradient downstream of it. By employing two different oil-film methods with upstream coating and full-coverage coating, a four-vortex model horseshoe vortex system can be identified ahead of each leading edge in the cascade, and the separation line of inlet boundary layer flow as well as the separation line of re-attached flow is provided as well. In addition, basic flow data such as secondary flow, aerodynamic loss, and flow turning angle downstream of the cascade are obtained.

• Membrane Journal
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• v.22 no.1
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• pp.62-71
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• 2012

In this study, for preparation of gas separation membrane with high permeability, hydroxy polyimide was synthesized using 6FDA and APAF. Synthesis of HPI was confirmed by H-NMR and FT-IR, thermal property of membrane was characterized by Differential scanning calorimetric (DSC) and thermogravimetric analyzer (TGA). Especially, the synthesized HPI can possible to search conversion to PBO at $450^{\circ}C$. To obtain the membrane having high permeability, ternary system consist of polymer, solvent and non-solvent additive was introduced, asymmetric HPI flat sheet membrane was prepared by phase inversion method. Finally, the change of morphology with each component was observed through FE-SEM.

• Korean Journal of Clinical Pharmacy
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• v.33 no.2
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• pp.122-127
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• 2023

Background: This study was aimed to identify the safety signals of metoclopramide in Korea Adverse Event Reporting System (KAERS) database by proportionality analysis methods. Methods: The study was conducted using Korea Institute of Drug Safety and Risk Management-Korea Adverse Event Reporting System Database (KIDS-KD) reported from January 2013 to December 2017 through KAERS. Signals of metoclopramide that satisfied the data-mining indices of proportional reporting ratio (PRR), reporting odds ratio (ROR) and information component (IC) were defined. The detected signals were checked whether they included in drug labels in the Ministry of Food and Drug Safety (MFDS), U.S. Food and Drug Administration (FDA) and Micromedex^®. Results: A total number of drug AE reports associated with all drugs of data in this study was 2,665,429. Among them, the number of AE reports associated with metoclopramide was 22,583. Forty-two meaningful signals of metoclopramide were detected that satisfied with the criteria of data-mining indicies. Especially neurological signals including extrapyramidal reactions, represented in the safety letter of regulatory agencies were identified in this study. Conclusion: Neurological signals of metoclopramide including extrapyramidal reactions were detected. It is believed that this search for signals can contribute to ensuring safety in the use of metoclopramide.

• Journal of Agricultural Extension & Community Development
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• v.21 no.4
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• pp.1227-1259
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• 2014

This paper explores agricultural extension systems, extension challenges, research and extension models, governance structures of agricultural extension and advisory services in Sudan. Agricultural extension services in Sudan are provided by a variety of governmental department and corporation. The Technology Transfer and Extension Administration under the Ministry of Agriculture and Irrigation, had been launched during mid 2000's aims at making extension systems farmer driven and farmer accountable by way of new institutional arrangements for technology dissemination in the form of community participation approach at the state level, to make the extension reforms have the active participation of farmers/farmer groups. The main problem facing agricultural extension services in developing countries is poor link between extension organization and research. Both extension administration and Agricultural Research Corporation (ARC) are operating as departments of ministry of Agricultural and irrigation for very long time. There are three recommendations to achieve the effectiveness of the Agricultural Research Corporations (ARC) in reaching farmers. Firstly, extension staff members should be assigned to every ARC station. Secondly, the ARC might increase positions for Agricultural development specialist or Farming System Research (FSR) specialist. Their role would be to reflect the needed of farmer and translate them to the researchable topics. Thirdly, researcher should conduct more research on farmer's fields.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.1
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• pp.78-85
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• 2023

This study evaluates the performance of reinforced concrete columns using hybrid fiber sheets for structural behavior. The purpose of this method is to improve the load-bearing capacity of the reinforced structure by impregnating a hybrid fiber sheet, which is woven by arranging aramid and glass fibers uniaxially and attached to an aged concrete structure requiring reinforcement with epoxy. In particular, not only the weight reduction of the material obtained by using a fiber lighter than the steel material, but also the low-strength, high-toughness fiber element among the fibers used delays the brittle fracture of the high-strength, low-toughness fiber element. The low-strength, high-toughness fiber element among the fibers used delays the brittle fracture of the high-strength, low-toughness fiber element, resulting in weight reduction compared to steel. The study conducted structural tests on four specimens, with the hybrid reinforcement method and failure mode as main variables. Specimen size and loading conditions were chosen to be comparable with previous studies. The structural performance of the specimen was evaluated using energy dissipation capacity and ductility. Analysis shows that excellent results can be obtained with the hybrid fiber sheet reinforcement.

• Journal of Life Science
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• v.23 no.7
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• pp.863-868
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• 2013

The XylP gene, which encodes endoxylanase in Bacillus sp. HY-20, was subcloned, and two expression plasmids, pG-xylP and pGMF-xylP were constructed. These plasmids, which contain different signal sequences, XylP s.s and $MF{\alpha}_{opt}$ s.s, respectively, for the secretory expression of endoxylanase, were transformed into Saccharomyces cerevisiae SEY2102 and FY833, respectively. The recombinant endoxylanases were successfully expressed, with a total activity range of 23.7-70.1 unit/ml according to the expression system and host strain. The endoxylanase activity in SEY2102/pGMF-xylP reached a maximum of 88.1 unit/ml in baffled flask culture. Most of the recombinant endoxylanase was efficiently secreted in the extracellular fraction, and the $MF{\alpha}_{opt}$ s.s was more efficient for secreting endoxylanase in yeast than the XylP s.s. Therefore, the expression system developed in this study produces large extracellular amounts of endoxylanase using S. cerevisiae as the host strain, and it could be used in bioethanol production and industrial applications.