컴퓨터 시스템의 성능 및 다양한 전산모사 프로그램의 발전으로 더 복잡한 원소로 이루어진 화학시스템의 해석이 가능해지고, 그에 따라 분자동역학 전사모사를 활용한 연구가 활발히 이루어지고 있다. 특히, 기존에는 실험위주로 진행되던 고분자 막에 대한 기체 투과 특성을 계산하는 연구가 관심을 받고 있고, 식품포장, 의약품등에 사용되고 있는 기체차단성 막 에 대한 분자동역학 연구가 많이 이루어지고 있다. 최근 실크 피브로인을 이용해 코팅막을 만들었을 때 기체 차단 효과가 나 타난다는 보고가 있었고, 본 연구에서는 이러한 실크 피브로인을 활용해 복합막을 만들었을 때 산소 차단 효과가 나타나는지 확인하고자 분자동역학 전산모사를 이용해 연구를 진행하였다. 단일 모델을 제작하고 기체 투과 특성을 계산하고 실험값과 비교를 통해 모델이 실제 실험 결과를 반영하는 것을 확인하였고, 실제 복합막 모델을 만들어 고분자 내에서 기체 이동경로 분석을 진행한 결과 산소 분자가 피브로인 영역을 통과하지 못하고 막히는 것을 보여주었다. 따라서, 실크 피브로인이 도입된 복합막이 산소 차단 성능이 우수하여, 식품포장 등에 유용할 것으로 기대된다.

In the nuclear fuel cycle (NFC) facilities, the failure of Heating Ventilation and Air Conditioning (HVAC) system starts with minor component failures and can escalate to affecting the entire system, ultimately resulting in radiological consequences to workers. In the field of air-conditioning and refrigerating engineering, the fault detection and diagnosis (FDD) of HVAC systems have been studied since faults occurring in improper routine operations and poor preventive maintenance of HVAC systems result in excessive energy consumption. This paper aims to provide a systematic review of existing FDD methods for HVAC systems therefore explore its potential application in nuclear field. For this goal, typical faults and FDD methods are investigated. The commonly occurring faults of HVAC are identified through various literature including publications from International Energy Agency (IEA) and American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). However, most literature does not explicitly addresses anomalies related to pressure, even though in nuclear facilities, abnormal pressure condition need to be carefully managed, particularly for maintaining radiological contamination differently within each zone. To build simulation model for FDD, the whole-building energy system modeling is needed because HVAC systems are major contributors to the whole building’s energy and thermal comfort, keeping the desired environment for occupants and other purposes. The whole-building energy modeling can be grouped into three categories: physics-based modeling (i.e., white-box models), hybrid modeling (i.e., grey-box models), and data-driven modeling (i.e., black-box models). To create a white-box FDD model, specialized tools such as EnergyPlus for modeling can be used. The EnergyPlus is open source program developed by US-DOE, and features heat balance calculation, enabling the dynamic simulation in transient state by heat balance calculation. The physics based modeling has the advantage of explaining clear cause-and-effect relationships between inputs and outputs based on heat and mass transfer equations, while creating accurate models requires time and effort. Creating a black-box FDD model requires a sufficient quantity and diverse types of operational data for machine learning. Since operation data for HVAC systems in existing nuclear cycle facilities are not fully available, so efforts to establish a monitoring system enabling the collection, storage, and management of sensor data indicating the status of HVAC systems and buildings should be prioritized. Once operational data are available, well-known machine learning methods such as linear regression, support vector machines, random forests, artificial neural networks, and recurrent neural networks (RNNs) can be used to classify and diagnose failures. The challenge with black-box models is the lack of access to failure data from operating facilities. To address this, one can consider developing black-box models using reference failure data provided by IEA or ASHRAE. Given the unavailability of operation data from the operating NFC facilities, there is a need for a short to medium-term plan for the development of a physics-based FDD model. Additionally, the development of a monitoring system to gather useful operation data is essential, which could serve both as a means to validate the physics-based model and as a potential foundation for building data-driven model in the long term.

Korean melon (Cucumis melo L.) is an environment in which most farming work can affect the increase in musculoskeletal diseases, and the stems are attracted to the ground in order to grow no-heating cultivation. In this study, growth and productivity were compared according to the type of high-bed. The narrower the surface area at the bottom of the high-bed, the faster the initial growth, which was advantageous. The bed is which the height if 70 cm, the surface temperature has risen due to the increase in direct solar radiation inflow since April, requiring side light blocking to block the inflow of solar radiation. In terms of fruit quality, the 200 cm width treatment had higher fruit sugar content and better hardness than the 160 cm treatment. From April to September, the total yield was 6.8 kg/plant of treatment A, 8.7 kg/plant of treatment B, 5.8 kg/plant of treatment C, treatment B mainly 50% higher than treatment C, and 27% higher than treatment A. Therefore, the bed form suitable for Korean melon high bed is 200 cm wide, 40 cm high between the surface and the bed, and the surface of the passage between the beds is 30cm high from the ground to the bed.

참외는 동북아시아 지역에서 대부분 재배되고 있고, 한국에 서 주로 생산되는 과일로서 단위면적당 수확량은 지속적으로 향상되고 있지만 재배방식은 토경재배에 국한되어 있기 때문 에 규모화, 생력화를 위한 수경재배 기술 개발이 필요하다. 본 연구에서는 보온부직포를 이용한 수경재배로 참외를 재배할 때 영양생장기 배양액 내 질산태질소 비율에 따른 참외 생육 의 변화를 확인했다. 배양액에서 질산태질소 비율이 증가할 수록 초장은 길어지고, 엽장, 엽폭, 절간장도 함께 증가하였다. 생육 30일차의 SPAD값은 질산태질소 비율이 증가할수록 감 소하였다. 질산태질소 비율에 낮을수록 암꽃 개화가 빨리 되 었고, 과실 성숙에서는 처리 간 차이가 없었다. 질산태질소 비 율에 따른 과실의 형태는 차이가 없었고, 경도는 질산태질소 의 비율이 낮을수록 높아 과실이 단단하였다. 3월에서 7월까 지 총 수확량은 KM3 5,650kg/10a, KM1 4,439kg/10a로 KM3가 27% 높았고 특히, 참외 가격이 높은 3월에서 5월까지 수량은 KM3가 KM1보다 36% 높았다. 따라서 12월 정식되 어 봄철부터 생산되는 참외의 수경재배에 적합한 질산태질소는 6.5－10me·L-1 수준으로 공급하는 것이 적당할 것으로 판 단되었다.

The domestic representative nuclear fuel cycle facilities are post-irradiation examination facility (PIEF) and Irradiated Examination Facility (IMEF) at KAERI. They have regularly operated since 1991 and 1993, respectively. Due to the long period of use, the facilities are ageing, and maintenance costs are increasing every year. The maintenance methods have mainly been breakdown maintenance (BM) and partially preventive maintenance (PM). They involve replacing components that have problems through periodic inspections by on-site inspectors. However, these methods are not only uncertain in terms of replacement cycles due to worker’s deviation on the inspection results, but also make it difficult to respond accidents developed through failures on the critical equipment that confines radioactive material. Therefore, an advanced operation and maintenance studied in 2022 through all of nuclear facilities operated at KAERI. Advancement strategy in four categories (safety, sustainability, performance, innovativeness) was analyzed and their priorities according to a facility environment were determined so a roadmap for advanced operation and maintenance could be developed. The safety and sustainability are higher importance than the performance and innovativeness because facilities at KAERI has an emphasis on research and development rather than industrial production. Thus, strategy for advancement has focused even more on strengthening the safety and sustainability. To enhance safety, it has been identified that immediate improvement of aged structures, systems, and components (SSCs) through large-scale replacement is necessary, while consideration of implementing an ageing management program (AMP) in the medium to long term is also required. Facility sustainability requires strengthening operation expertise through training, education, and cultivation of specialized personnel for each system, and addressing outstanding regulatory issues such as approval of radiation environment report on the nuclear fuel processing facilities and improvement work according to fire hazard analysis. One of the safety enhancement methods, AMP, is a new maintenance approach that has not been previously applied, so it had to be thoroughly examined. In this study, an analysis was conducted on the procedure and method for introducing an AMP. An AMP for nuclear fuel cycle facilities was developed by analyzing the AMP applied to the BR2 research reactor in Belgium and modifying it for application to nuclear fuel cycle facilities. The ageing management for BR2 has the objective to maintain safety, availability and cost efficiency and three-step process. The first step is the classification of SSCs into four classes to apply graded approach. Secondly, ageing risk is assessed to identify critical failure modes, their frequency and precursors. Final step involves defining measures to reduce the ageing risk to an acceptable level in order to integrate the physical and economic aspects of ageing into a strategy for inspection, repair, and replacement. Similar approach was applied to the nuclear fuel cycle facility. Firstly, the SSCs of nuclear fuel cycle facilities have been classified according to their safety and quality classifications, as well as whether they are part of the confinement boundary. The SSCs involved in the confinement boundary were given more weight in the classification process, even if they are not classified as safety-class. A risk index for ageing was introduced to determine which prevention and mitigation measure should be chosen. By multiplying the health index and the impact index, the ageing risk matrix provides a numerical score that represents guidance on the prevention and mitigation of ageing effect. The health index is determined by combining the likelihood of failure and engineering evaluation of the current condition of SSCs, whereas the impact index is calculated by taking into account the severity of consequences and the duration of downtime resulting from a failure. This ageing management has to be thoroughly reviewed and modified to suit each facility before being applied to nuclear fuel cycle facilities.

화석연료의 사용에 따른 지구 온난화 및 기상 이변으로 인하여 온실가스 저감 문제가 대두되고 있으며, 그에 따 라 에너지 소모 없이 셀프 쿨링이 가능한 소재에 대한 연구가 활발히 진행되고 있다. 그 중에서도 실크는 천연 쿨링 소재로 알려져 있으나, 기존의 혼합 공정에서는 실크를 화학적으로 분말화 시키기 때문에 복사 냉각 효과가 사라지는 문제점이 있어, 복사냉각을 위한 필름 또는 코팅제 형태로 제조하는데 어려움을 겪고 있다. 본 연구에서는 실크 피브로인의 고유구조를 훼손 하지 않는 물리적 분쇄 공정을 거친 실크 분말을 사용하여 다양한 형태의 막을 제조하고, 코팅제로서의 적용가능성을 살펴보 고자 연구를 수행하였다. 이를 위해 실크 피브로인 분말이 도입된 전기방사 복합막 및 평막 형태의 복합막을 제조하였으며, 용액의 점도가 막 제조 및 제조된 막의 물성에 큰 영향을 미치는 것을 관찰하였다.

Background: The leaf temperature (TLEAF) is one of the most important physical parameters governing water and carbon flux, including evapotranspiration, photosynthesis and respiration. Cnidium officinale is one of the important folk medicines for counteracting a variety of diseases, and is particularly used as a traditional medicinal crop in the treatment of female genital inflammatory diseases. In this study, we developed a model to estimate TLeaf of Cnidium officinale Makino based on black globe temperature (TBGT). Methods and Results: This study was performed from April to July 2018 in field characterized by a valley and alluvial fan topography. Databases of TLEAF were curated by infrared thermometry, along with meteorological instruments, including a thermometer, a pyranometer, and an anemometer. Linear regression analysis and Student’s t-test were performed to evaluate the performance of the model and significance of the parameters. The correlation coefficient between observed TLEAF and calculated TBGT obtained using an equation, developed to predict TLEAF based on TBGT was very high (r2 = 0.9500, p < 0.0001). There was a positive relationship between TBGT and solar radiation (r2 = 0.8556, p < 0.0001), but a negative relationship between TBGT and wind speed (r2 = 0.9707, p < 0.0001). These results imply that heat exchange in leaves seems to be mainly controlled by solar radiation and wind speed. The correlation coefficient between actual and estimated TBGT was 0.9710 (p < 0.0001). Conclusions: The developed model can be used to accurately estimate the TLeaf of Cnidium officinale Makino and has the potential to become a practical alternative to assessing cold and heat stress.

Background : Angelica tenuissima Nakai is a major medicinal plant around GyeoungBuk Area. Powdery mildew of Angelica tenuissima Nakai caused a Erysiphe heraclei DC. is a major disease. It was found leaf of Angelica tenuissima after rainy season. There was no agicultural chemical registration on Angelica tenuissima. Ecofriendly control needs Angelica tenuissima for GAP. Methods and Results : The seedlings used for the test were sowed and cultivated in mid-February at Bonghwa herbal crop research institute. The irrigation water was irrigated through a drip irrigation system. Powdery mildew occurred after rainfall lasted more than 2 days at the end of June. The pathogen (Erysiphe heraclei DC.) was identified by observing the diseased plants with an optical microscope. Bordeaux mixture was tested using Gold Bordeaux which was listed in the eco-friendly material list and the magnification was 500 times for the medicinal efficacy test and 250 times for the damage test. For the chemical treatment 40 ㎖ of Bordeaux mixture was added to 20 ℓ of water to prepare 500 times of the solution and the treatment was sufficiently wetted to the plant at about 8:00 am. The first treatment was treated at 7. 5 days, the second treatment at 7. 13 days, the third treatment at 7. 26 days, and the final investigation at 7.26 days. The occurrence of powdery mildew was sufficient to evaluate the treatment effect at 13.0% in untreated control and the control value was low at 33.5% in one treatment but 74.0% in control after 2 treatments showed significant control effect. 89.2% respectively. As a result it is effective to control the powdery mildew of Bordeaux solution at least once every seven days to improve the control effect. Conclusion : Control value of bordeaux mixture was higher than after two times of treatment. Bordeaux mixture treatment of powdery mildew on Angelica tenuissima control 89.2% and it can use a producing ecofriendly agricultural product.

Background : Angelica dahurica, Ligusticum sinense and Ledebouriella seseloides are cultivated in small areas in Korea. Domestic cultivation area is around 10 ha, and cultivated varieties have not been developed yet. Therefore, the quality of the product is not uniform, and industrialization is difficult. Lately, studies on the development of varieties have been carried out using domestic collecting germplasm. Methods and Results : Germplasm was collected in Gangwon-do, Chungcheongbuk-do, Gyeongsangbuk-do, Jeollanam-do and Jeju-do and sowed in pots in March 2017. Angelica dahurica was used the collected in Gyeongsangbuk-do, Jeollanam-do, Ligusticum sinense was used the collected in Gangwon-do and Gyeongbuk-do and Ledebouriella seseloides was used the collected Jeju-do. In May of 2017, those were planted and the stem and leaf characteristics were compared and analyzed 1-year. It was bloomed in the second years of 2018, and stem, leaf and flowering characteristics were compared and analyzed. In the first year of growth characteristics, Angelica dahurica showed lower leaf and stem growth in Jeollanam-do collected germplasm. However, there was no statistical significance. Growth characteristics of Ligusticum sinense were higher in Gangwon-do collection than in Gyeongsangbuk-do, but there was no statistical significance. Ledebouriella seseloides was no significant difference between the groups in Jeju-do. In the second years, individual selection were carried out for popullation improvement. The Angelica dahurica showed green and purple stalks and the collected germplasm of Jeollanam-do showed relatively low growth. Ligusticum sinense and Ledebouriella seseloides were no significant differences in growth and color between stem and leaf, stem and stem Conclusion : All three crops were cross pollination, and collected open pollination. Therefore, there were many segregation by germplasm and genetic variation was large. Furthermore, it is considered that statistical significance does not appear. If genetic uniformity is increased through continuous selection and population improvement, it will be possible to cultivate varieties using germplasm. Genetic variation will be a good source of genetic resources.

Background : Rehmannia glutinosa is a perennial herb belonging to family Scrophulariaceae. This study was breeding of R. glutinosa cultivar with insect tolerance and high-yielding. Methods and Results : ‘Chunggang’ is developed by the medicinal crop breeding team of National Institute of Horticulture and Herbal Science (NIHHS), Rural Development Administration (RDA), during the period from 2005 to 2017. The reproduction of Rehmannia glutinosa has been accomplished mainly by vegetative propagation with its seedlings. This cultivar was selected from seedling of RG10. The plant type of Chungang is some rising from ground. Regional yield trials conducted at three site from 2016 to 2017. The root yield of ‘Chunggang’ was 22.3 ton per hectare, which was increased 11% compared with ‘Jihwang 1’ (check variety). Also, ‘Chunggang’ has higher insect tolerance compared with ‘Jihwang 1’. Conclusion : ‘Chunggang’ is a insect tolerance and high-yielding Rehmannia glutinosa cultivar.