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        81.
        2022.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study was to examine the extent to which influencing factors impact the transference willingness of farmers. The research method is based on the survey data on transference willingness, and the binary logistic model was used to analyze the influencing factors. The results show that the educational level, annual household income, farm labor, and farmers' understanding of land transfer policy notably influence land transfer. Based on the results, suggestions include improving farmers' social security system, improving a sound market for rural land transfer, and deepening the promotion and explanation of land-related policies.
        4,000원
        82.
        2022.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Natural environmental resources are considered a prospective source of microorganisms capable of producing biocatalysts with great potential in industrial areas. Arable soil fertilized with peat moss is a habitat for various microorganisms. The present research focused on the isolation and identification of hydrolase-producing bacteria that thrive at a broad temperature range. In this study, a total of 33 strains were isolated from arable soil fertilized with peat moss (Silla Garden in Busan, South Korea). The isolated bacteria were mesophiles and thermophiles with a wide temperature range. Taxonomic identification showed that the isolated strains belonged to 2 phyla, 5 families, 10 genera, and 24 species. Subsequently, the isolated strains were screened for hydrolase (amylase, lipase, and protease) activity. All isolates possessed activity of at least one enzyme and six bacterial isolates produced combined extracellular enzymes. Diversity of soil bacteria species in the present study suggest the potential of soil bacteria in the various industrial applications.
        4,000원
        83.
        2022.05 구독 인증기관·개인회원 무료
        Gamma-ray spectroscopy, which is an appropriate method to identify and quantify radionuclides, is widely utilized in radiological leakage monitoring of nuclear facilities, assay of radioactive wastes, and decontamination evaluation of post-processing such as decommissioning and remediation. For example, in the post-processing, it is conducted to verify the radioactivity level of the site before and after the work and decide to recycle or dispose the generated waste. For an accurate evaluation of gamma-ray emitting radionuclides, the measurement should be carried out near the region of interest on site, or a sample analysis should be performed in the laboratory. However, the region is inaccessible due to the safety-critical nature of nuclear facilities, and excessive radiation exposure to workers could be caused. In addition, in the case of subjects that may be contaminated inside such as pipe structures generated during decommissioning, surveying is usually done over the outside of them only, so the effectiveness of the result is limited. Thus, there is a need to develop a radiation measurement system that can be available in narrow space and can sense remotely with excellent performance. A liquid light guide (LLG), unlike typical optical fiber, is a light guide which has a liquid core. It has superior light transmissivity than any optical fiber and can be manufactured with a larger diameter. Additionally, it can deliver light with much greater intensity with very low attenuation along the length because there is no packing fraction and it has very high radiation resistant characteristics. Especially, thanks to the good transmissivity in UV-VIS wavelength, the LLG can well transmit the scintillation light signals from scintillators that have relatively short emission wavelengths, such as LaBr3:Ce and CeBr3. In this study, we developed a radiation sensor system based on a LLG for remote gamma-ray spectroscopy. We fabricated a radiation sensor with LaBr3:Ce scintillator and LLG, and acquired energy spectra of Cs-137 and Co-60 remotely. Furthermore, the results of gamma-ray spectroscopy using different lengths of LLG were compared with those obtained without LLG. Energy resolutions were estimated as 7.67%, 4.90%, and 4.81% at 662, 1,173, and 1,332 keV, respectively for 1 m long LLG, which shows similar values of a general NaI(Tl) scintillator. With 3 m long LLG, the energy resolutions were 7.92%, 5.48%, and 5.07% for 662, 1,173, and 1,332 keV gamma-rays, respectively.
        84.
        2022.05 구독 인증기관·개인회원 무료
        In this study, the positions of Cs-137 gamma ray source are estimated from the plastic scintillating fiber bundle sensor with length of 5 m, using machine learning data analysis. Seven strands of plastic scintillating fibers are bundled by black shrink tube and two photomultiplier tubes are used as a gamma ray sensing and light measuring devices, respectively. The dose rate of Cs-137 used in this study is 6 μSv·h−1. For the machine learning modeling, Keras framework in a Python environment is used. The algorithm chosen to construct machine learning model is regression with 15,000 number of nodes in each hidden layer. The pulse-shaped signals measured by photomultiplier tubes are saved as discrete digits and each pulse data consists of 1,024 number of them. Measurements are conducted separately to create machine learning data used in training and test processes. Measurement times were different for obtaining training and test data which were 1 minute and 5 seconds, respectively. It is because sufficient number of data are needed in case of training data, while the measurement time of test data implies the actual measuring time. The machine learning model is designated to estimate the source positions using the information about time difference of the pulses which are created simultaneously by the interaction of gamma ray and plastic scintillating fiber sensor. To evaluate whether the double-trained machine learning model shows enhancement in accuracy of source position estimation, the reference model is constructed using training data with one-time learning process. The double-trained machine learning model is designed to construct first model and create a second training data using the training error and predetermined coefficient. The second training data are used to construct a final model. Both reference model and double-trained models constructed with different coefficients are evaluated with test data. The evaluation result shows that the average values calculated for all measured position in each model are different from 7.21 to 1.44 cm. As a result, by constructing the double-trained machine learning model, the final accuracy shows 80% of improvement ratio. Further study will be conducted to evaluate whether the double-trained machine learning model is applicable to other data obtained from measurement of gamma ray sources with different energy and set a methodology to find optimal coefficient.
        85.
        2022.05 구독 인증기관·개인회원 무료
        Since nuclear power plant (NPP) dismantling carries the possibility of radiation exposure from a hazardous environment, it’s important to minimize that by using a remote manipulator et al. However, due to complexity of nuclear facilities, it’s necessary for operators to increase their proficiency by operating in advance in a virtual environment. In this research, we propose a virtual manipulator system using a haptic device for NPP’s reactor vessel internals (RVI) dismantling which can realistically manipulate.
        86.
        2022.05 구독 인증기관·개인회원 무료
        The mechanical safety of the container designed according to the IP-2 type technology standard was analyzed for the temporary storage and transportation of Very-Low-Level-Waste (VLLW) for liquid occurring at the nuclear facilities decommissioning site. The container was designed and manufactured as a composite shielding container with the effect of storing and shielding liquid radioactive waste using High Density Polyethylene (HDPE) and eco-friendly shielding material (BaSO4) with corrosion and chemical resistance. The main material of the composite shielding container is HDPE and BaSO4, the material of the cover, cage and pallet is SUS304, and the angle guard is elastic rubber. The test and analysis requirements were analyzed for structural analysis of container drop and lamination test. As test requirements for IP-2 type transport containers should be verified by performing drop and lamination tests. There should be no loss or dispersion of contents through the 1.2 m high free-fall drop and lamination test for a load five times the amount of transported material. ABAQUS/Explicit, a commercial finite element analysis program, was used for structural analysis of the drop and lamination test of the transport and storage container. (Drop test) It was confirmed that the container was most affected when it falls from a 45-degree slope. Although plastic deformation was observed at the edge axis of the cover, it was evaluated that the range of plastic deformation was limited to the cover and cage, and stress within the elastic limit occurred in the inner container. In the analysis results for other falling direction conditions, it was evaluated that stress within the elastic limit was generated in the inner container except for minor plastic deformation. In the case of on-site simulation evaluation, deformation of the inner container and frame due to the drop impact occurred, but leakage and loss of contents, which are major evaluation indicators, did not occur. (Lamination test) The maximum stress was calculated to be 19.9 MPa under the lamination condition for a load 5 times the container weight, and the maximum stress point appeared at the corner axis of the pallet. The calculated value for the maximum stress is about 10%, assuming the conservative yield strength of SUS304 is 200 MPa. It was evaluated that stress within the limit occurred. In the case of on-site simulation evaluation, it was confirmed that there was no container deformation or loss of contents due to the load.
        87.
        2022.05 구독 인증기관·개인회원 무료
        As the plan for the nuclear dismantlement due to the permanent shutdown of Kori-1 and Wolseong- 1 nuclear power plants has been concretized, a “movable radionuclide analysis system” is being developed that can quickly and accurately analyze large amounts of radioactive waste generated on the sites during dismantling. This system has various advantages from the perspective of strict regulations on the radioactive waste movement and social acceptability, such as preventing unexpected accidents while moving on the national highway or expressway, reducing various documents and immediate response to dismantling plans. Currently the system is being developed to be equipped with previously developed sample pretreatment and radioactivity measuring equipment and automated volatile and nonvolatile nuclide separation equipments, but to ensure mobile stability, it needs to analyze factors and establish stability standards. In the KS Q ISO/IEC 17025:2017 standard, the requirements for “facilities and environmental conditions” are a very important factor in building reliability for consumers as part of the quality guarantee for this facility. In order to meet the requirements, the technical standards of various test equipment to be installed in this facility were investigated. The physical, chemical, and radiological hazards that could affect the safety of the equipment and workers in the process of moving the equipment between nuclear power plants or between nuclear dismantling sites were derived from vibrations, rapid changes in temperature and humidity, and the spread of contamination from radioactive waste samples. Therefore, the scope of application of the law, which is the basis for securing stability during movement, was classified into two situations: movement from facility manufacturer to installation site (non-contaminated) and movement from primary to secondary use (contaminated). And in order to investigate the Nuclear Safety Act, enforcement ordinances, and radiation safety management, and to establish standards for packaging and transportation of radioactive materials, the results of transportation tests and transport details were compared and analyzed. Finally, the air suspension systems and the automatic temperature and humidity control devices were analyzed to establish standards for securing stability against the vibration and the sharp changes in the temperature and humidity, and countermeasures such as accident measures in accordance with the Enforcement Decree of the Nuclear Safety Act were also investigated.
        90.
        2022.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In vivo oocytes grow and mature in ovarian follicles whereas oocytes are matured in vitro in plastic culture dishes with a hard surface. In vivo oocytes show a superior developmental ability to in vitro counterparts, indicating suboptimal environments of in vitro culture. This study aimed to evaluate the influence of an agarose matrix as a culture substrate during in vitro maturation (IVM) on the development of pig oocytes derived from small antral follicles (SAFs). Cumulusoocyte complexes (COCs) retrieved from SAFs were grown in a plastic culture dish without an agarose matrix and then cultured for maturation in a plastic dish coated without (control) or with a 1% or 2% (w/v) agarose hydrogel. Then, the effect of the soft agarose matrix on oocyte maturation and embryonic development was assessed by analyzing intra-oocyte contents of glutathione (GSH) and reactive oxygen species (ROS), expression of VEGFA, HIF1A , and PFKP genes, and blastocyst formation after parthenogenesis. IVM of pig COCs on a 1% (w/v) agarose matrix showed a significantly higher blastocyst formation, intra-oocyte GSH contents, and transcript abundance of VEGFA. Moreover, a significantly lower intra-oocyte ROS content was detected in oocytes matured on the 1% and 2% (w/v) agarose matrices than in control. Our results demonstrated that IVM of SAFs-derived pig oocytes on a soft agarose matrix enhanced developmental ability by improving the cytoplasmic maturation of oocytes through redox balancing and regulation of gene expression.
        4,000원
        91.
        2022.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        People differ greatly in their capacity to persist in the face of challenges. Despite significant research, relatively little is known about cognitive factors that might be involved in perseverance. Building upon human threat-management mechanism, we predicted that perseverant people would be characterized by reduced sensitivity (i.e., longer detection latency) to threat cues. Our data from 5,898 job applicants showed that highly perseverant individuals required more time to correctly identify anger in faces, regardless of stimulus type (dynamic or static computer-morphed faces). Such individual differences were not observed in response to other facial expressions (happiness, sadness), and the effect was independent of gender, dispositional anxiety, or conscientiousness. Discussions were centered on the potential role of threat sensitivity in effortful pursuit of goals.
        4,000원
        92.
        2022.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The prevalence of cancer in companion dogs is growing nowadays with the increasing worldwide population of domestic dogs. Since there is a less established standard of care in veterinary medicine, investigational treatments, such as the development of biomarkers can be considered as a therapeutic intervention for early diagnosis. Despite the enormous efforts that have been invested in the search of biomarkers, still, there is a need for easy detection of significant biological markers for predicting canine cancers at an early stage. In this study, we have analyzed the expression pattern of previously reported 46 canine cancer-associated candidate genes in blood specimens using real-time qPCR. We hypothesized that analysis of gene expression in blood would provide preliminary evidence of local or systemic immunogenic response which further contribute to the easy and early diagnosis of canine cancer from blood specimen as an analytical tool. The datasets included a total of 22 blood samples collected from different breeds of dogs diagnosed with cancer and five from healthy normal dogs. RT-qPCR analysis was performed by employing the SYBR Green PCR mix to assess the expression of these 46 genes in a total of 27 samples. From our result, a total of nine genes (ROS1, C1QA, CD48, IL1b, TLR2, IL2R, CHI3L1, CTSS, and TLR7) were found to be significantly up-regulated (p < 0.05 and p < 0.01) in the cancer samples compared to non-cancer samples. The relative expression level of ROS1, C1QA, CD48, IL1b, TLR2, IL2R, CHI3L1, CTSS, and TLR7 genes was 5.74, 4.78, 3.94, 2.94, 2.57, 2.53, 2.50, 2.04, and 2.57, respectively, in cancer samples compared to non-cancer samples. Thus, our results reveal several highly expressed cancer genes that can be therapeutic target genes for further testing in canine cancers.
        4,000원
        93.
        2022.03 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        This study reports Chinese and Korean university EFL students’ perceptions of and attitudes toward online and face-to-face English language learning modes during COVID-19. Few previous studies have focused on how students thought of online and face-to-face learning experiences of subjects regarding new concept learning and delivery of new contents. Research gravitating around English courses showed students' mixed perceptions. The survey was conducted for 302 Korean and 337 Chinese university students who took communication-oriented English courses. Descriptive statistics and qualitative data analysis were used for analysis. Results indicated that students preferred face-to-face English learning with some specific indications of achieving a stronger help and quality for communicative competence in language. Online learning also benefited students with a sense of both flexibility and independence. Positive components of face-to-face learning for language education might be considered for online education while incorporation features such as flexibility and independence to enrich language education during COVID-19.
        6,400원
        94.
        2022.01 KCI 등재 구독 인증기관 무료, 개인회원 유료
        연구는 참외 재배 지에서 흰가루병, 담배가루이 및 두점박이응애가 동시에 발생하였을 때 45, 40, 35°C (대조구)의 온도에서 측창으로 환기 처리 시, 온실 내 온 ․ 습도의 변화, 병충해 발생과 잎말림, 그리고 개화조절에 미 치는 효과를 검토하였다. 3월 3일 ‘히든파워’ 대목에 접붙여진 ‘알찬꿀’ 참외를 40cm 간격으로 격리상에 심었고, 위 에 언급한 병해충이 모든 처리구에서 발생한 6월 18일부터 7월 13일까지 처리하였다. 온실의 온도는 맑은 날에는 설정 온도 지점까지 증가되었고, 45°C 환기 처리에서 고온 고습이 약 9시간 동안 유지되었다. 주간 최고 기온과 최 저 상대습도 차이는 45°C 환기 처리에서 가장 높았다. 환기 처리 11일 후에는 흰가루병과 두점박이응애 피해가 45°C 환기 처리에서 거의 회복되었지만 40°C와 35°C에서는 그렇지 않았다. 처리 14일 후, 담배가루이와 두점박이 응애 밀도는 45°C에서 유의하게 감소하였으나 흰가루병 증상은 유의하게 감소하지는 않았다. 잎말림은 고온에서 유발되었으나 45°C에서도 심하지 않았다. 처리 26일 후, 새로 나온 줄기의 15 마디의 개화수를 조사한 결과, 45°C에 서 암꽃이 전혀 나오지 않았고 수꽃은 1.2개로 나타났다. 이상의 결과는, 고온기에 45°C의 고온에서 2-3주간 환기 처리는 온실 내부의 고온 고습을 유도하여 흰가루병, 담배가루이, 두점박이응애를 통제하고, 개화를 억제하여 참외 의 영양 생장을 회복할 수 있는 방법으로 사료되었다.
        4,000원
        95.
        2021.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        기술 트렌드가 증가함에 따라, 엄청난 양의 데이터가 생성되고 있습니다. 많은 양의 데이터가 소비되는 기술 분야 중 하나는 컴퓨터 비전이다. 인간은 기계와 비교할 때 시각에 영향을 미치는 표정, 조명 또는 시야각과 같은 외부 조건에서도 얼굴이나 사물을 쉽게 감지하고 인식할 수 있다. 그 이유는 그것과 관련된 높은 차원 의 데이터 때문이다. 데이터 차원성은 모든 관측치에서 측정되는 변수의 총 수를 말합니다. 이번 사업은 안 면인식시스템에 적합한 다양한 차원감소 기법을 비교하고 조도가 다양한 안면이미지로 구성된 다양한 데이 터세트로 테스트해 모델의 정확도 향상에 도움이 되는 기법의 앙상블 모델을 제안하고 성능을 측정하는 것 이 목적이다.렉스 배경과 표현. 제안된 앙상블 모델은 주성분 분석(PCA)과 로컬 선형 임베딩(LLE)이라는 두 가지 차원 감소 기술의 혼합에서 벡터를 추출하고, 이를 밀도 높은 컨볼루션 신경망(CNN)을 통해 전달하여 야생 면(LFW) 데이터 세트의 얼굴을 예측한다. 이 모형은 0.95의 검정 정확도와 0.94의 검정 F1 점수로 수행 됩니다. 제안된 시스템은 시스템이 얼굴을 예측할 수 있는 제안된 앙상블 모델과 통합된 웹캠에서 라이브 비 디오 스트림을 캡처하는 플라스크를 사용하여 개발된 웹 앱을 포함한다.
        4,600원
        96.
        2021.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 최근 코로나19 여파로 가파른 성장세를 보이고 있는 1인 게임 방송의 시청이 이를 송출하는 인터 넷 방송 플랫폼의 속성과 연관성이 있을 것으로 보았다. 본 연구에서는 설문조사를 통해 1인 게임 방송의 시 청 동기를 도출한 후, 시청 동기와 이용자 특성이 플랫폼 자체 속성과 이용자 속성에 미치는 영향을 검증하 기 위해 다중 회귀분석을 실시하였다. 연구결과, 인터넷 방송 플랫폼을 통해 게임 콘텐츠를 시청하는 이용자 들은 참여자들 간의 상호작용과 플랫폼 자체의 편리성과 정보 전달 속도를 중요시 하는 것으로 확인되었다. 이러한 속성들은 더 큰 데이터의 전송과 소통의 중요성이 강조되는 메타버스 영역에서도 적용될 수 있을 것 으로 보이며, 메타버스와 함께 더욱 확장되어 나갈 게임 방송 플랫폼의 발전을 위한 실무적 함의를 제공하고 자 한다.
        4,900원
        97.
        2021.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        농촌 종점 물류는 농촌 주민들의 온라인 쇼핑에 영향을 주는 중요한 요인임. 농촌 인터넷 쇼핑의 서비스 품질은 양호한 종점 물류 배송과 지원이 필요함. 농촌 이커머스의 발전에 의 하여 농촌 주민들이 서비스의 품질에 대한 기대치도 높아지고 있음. 본 연구에서는 이커머스 만족도를 통한 농촌 종점 물류 서비스 품질이 농촌 주민의 온라인 구매행위에 어떠한 영향 미치는지 검토하고, 농촌 종점 물류 서비스의 발전을 위한 개 선 및 발전전략을 제시하였음. 본 연구에서는 구조방정식모델 (SEM)과 온충린의 매개효과 테스트를 적용하여 분석하였음. 1. 신뢰성과 서비스 편의성은 만족도에 긍정적 영향을 미치며, 원가절약은 만족도에 부정적 영향을 미침. 2. 만족도는 인터넷 쇼핑에 긍정적인 영향을 미치는 것으로 나타났음. 3. 만족도는 반응성과 구매행위 사이에 매개효과가 있고 경제와 구매행위 사이에도 매개효과가 있는 것으로 나타났음.
        4,600원
        98.
        2021.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The growth characterization and enzyme productivity of halotolerant microorganisms isolated from the Nakdong River estuary wetland in Korea were investigated in this study. The isolation of halotolerant microorganisms was carried out through their cultivation at 37oC for several days using a marine agar medium. After a single-colony isolation, 16 pure colonies were obtained, and phylogenetic analysis was done using 16S-based ID service in the EzBioCloud database. The isolated strains were divided into 3 phyla, 5 families, 7 genera, and 13 species. Possible industrial applications of the strains were confirmed upon testing for amylolytic, lipolytic, and proteolytic activity to confirm the possible production of hydrolytic enzymes, growth at a pH range of 5 to 9, and various salt concentrations being tested. Thirteen strains possessed at least one enzyme activity, and 5 strains possessed 2 enzyme activities. Eight strains could tolerate up to 10% NaCl concentration. This result indicated that isolated strains had shown the possible application in food and cosmetic industries. Therefore, this study would contribute to securing domestic biological resources and improving hydrolytic enzyme activity using these strains.
        4,000원
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