Safeguards systems and measures are determined through diversion scenario analysis based on the facility design information submitted to the IAEA when a new nuclear facility is introduced. While the concept of safeguards-by-design (SBD), which considers the safeguards from the design phase for a facility operator to minimize unplanned changes or disruption to facility operations as well as for the IAEA to increase the efficiency and effectiveness in safeguards implementation, has been emphasized for more than a decade, there is no practical tool or guidance on how to apply it. In this study, we develop a diversion path analysis tool and introduce how to apply SBD using it. A diversion path analysis tool was developed based on the elements that constitute diversion and the algorithm generated based on the initial information of facility and nuclear material flow. The results of utilizing the analysis tool depending on a different level of facility information and the safeguards set-ups were compared through examples. Taking a typical light water reactor as an example, the test analyzed the automatic generation of dedicated routes, configuration of safeguards measures, and diversion path analysis. Through this, the application and limitations of the analysis tool are discussed, and ideas for utilization according to the SBD concept and necessary regulatory guidance are proposed. The results of this study are expected to be directly utilized to domestic nuclear control during the regulation process for a construction of new nuclear power systems, and furthermore, to enhance national credibility in the engagement with the IAEA for implementation of safeguards.

To evaluate the safeguards system or performance in a facility, it is crucial to analyze the diversion path for nuclear materials. However, diversion paths can range from the extremely simplified to the complicated depending on the level of knowledge and the specific person conducting the analysis. This study developed the diversion path analysis tools using an event tree and fault tree method to generating diversion paths systematically. The essential components of the diversion path were reviewed, and a logical flow was developed for systematically creating the diversion path. An algorithm was created based on the facility design components and logical flow, as well as the initial information of the nuclear materials and material flows. The event tree and fault tree analysis tools were used to test the path generation algorithm. The usage and limitations of these two logic methods are discussed, and ideas to incorporate the logic algorithm into practical program tools are suggested. The tests were analyzed on a typical light water reactor as an example, including automatic generation of dedicated pathways, configuration of safeguards measures, and analyzing paths with strategies for avoiding safeguard systems. The results led to the development of a draft pathway analyzer program that can be applied to general nuclear systems. The results of this study will be used to develop a program module that can systematically generate diversion paths using the event tree and fault tree method. It can help to guide and provide practical tools for implementing SBD.

Even though it is emphasized to apply safeguards-by-design (SBD) concept in the early phase of the design of a new nuclear facilities, there is no clear guideline or tools for the practical SBD implementation. Generally known approach is trying to review whether there is any conflicts or shortcomings on a conceptual safeguards components in a design information. This study tries to build a systematic tools which can be easily applied to safeguards analysis. In evaluating the safeguards system or performance in a facility, it is essential to analyze the diversion path for nuclear materials. Diversion paths, however, can be either extremely simplified or complicated depending on the level of knowledge and purpose of specific person who do analyze in the field. In the context, this study discusses the applicability of an event tree and fault tree method to generating diversion paths systematically. The essential components constituting the diversion path were reviewed and the logical flow for systematically creating the diversion path was developed. The path generation algorithm based on the facility design components and logical flow as well as the initial information of the nuclear materials and material flows was test using event tree and fault tree analysis tools. The usage and limitation of the applicability of this two logic methods are discussed and idea to incorporate the logic algorithm into the practical program tools is suggested.The results will be used to develop a program module which can systematically generate diversion paths using the event tree and fault tree method.

In order to effectively and efficiently apply safeguards to new nuclear facilities, it is recommended to apply safeguards-by-design concept. In evaluating the safeguards in the early stage of the design of a facility, it is essential to analyze the diversion path for nuclear materials. This study suggests a simple method which can generate diversion paths. The essential components constituting the diversion path were reviewed and the logical flow for systematically creating the diversion path was developed. The path generation algorithm is based on this components and logical flow as well as the initial information of the nuclear materials and material flows in a planned facilities. The results will be used to develop a program module which can systematically generate diversion paths using the event tree and fault tree method.

본 연구는 여름철 장미의 수출 환경 조건에서 황금(Scutellaria baicalensis) 추출물(SC용액, 특허출원번호 10-2019-0109867)의 절화수명연장 효과를 확인하고 수입산 절화보존제의 대체 가능성을 알아보고자 수행되었다. 건식 및 습식 수송 조건으로 구분하고, 습식 수송 조건은 절화보존제 처리 유무와 종류 에 대한 비교분석을 위해 물(tap water), Floralife 1%, SC용 액 300mg･L-1를 처리하였다. 그 결과, 절화수명 연장에는 습식수송 조건에서 절화보존제를 사용하는 것이 유리하였다. 특히 황금추출물 SC용액 처리구의 절화수명은 수돗물(7.7일)보다 1.7일 연장되었으며, 이러한 효과는 수입산 절화보존제인 Floralife의 효과와 유사하였다. 절화수명 종료 증상은 건식 수송 조건 경우 화색의 퇴화 증상이 상대적으로 많았으며, 습식 수송 조건의 경우 일반적인 장미 절화의 노화 증상인 꽃목굽 음과 꽃잎마름 증상이 전체의 60~70%를 차지하였다. 결론적으로 여름철 장미의 수출 환경에서 SC용액은 절화수명을 효 과적으로 연장시킬 수 있었으며, 그 효과는 기존 절화보존제인 floralife와 유사하여 친환경 대체 절화 보존제로 적용이 가능할 것으로 판단된다.

Developmental characteristics of immature stages of Ostrinia scapulalis (Lepidoptera: Crambidae), which is a main insect pest against legume crops, were investigated at constant temperatures to prepare fundamental data for integrated pest management. Egg, larva and pupa could survive at temperatures from 16oC to 36oC. Developmental periods of those stages became shorter with increasing temperature between 16 and 31oC, 16 and 36oC, and 16 and 34oC, respectively. The lower developmental thresholds and degree-days(DD) were determined as 13.0oC and 56.9DD, 13.8oC and 277.5DD, and 14.2oC and 90.8DD using a linear regression model between temperature and development rate. Other parameters for explaining development of this species were estimated using a few non-linear models for developmental rate, distribution, and survivorship.

거미는 산림 및 농작물 해충의 천적으로 알려져 있으며, 겨울철 벼 재배지에서 볏짚이나 논둑 등에 월동한다. 이 연구는 월동시기부터 모내기 전까지 유기 벼 재배지에 서식하는 거미상을 알아보기 위해 수행하였다. 거미의 발생을 조사하기 위해 함정트랩을 이용하였고, 농업과학원 유기재배포장에서 2018년 1월 중순부터 5월 중순까지 2주 간격으로 총 8회에 걸쳐 거미를 채집하였다. 조사가 이루어진 논은 거미가 월동 서식처로 이용할 수 있도록 볏짚을 걷어내지 않은 상태로 유지하였다. 조사 결과 6과 15종 359개체의 거미가 채집되었다. 그 중에서 애접시거미가 119개체(33%)로 가장 많았고, 들늑대거미(23%), 턱거미(17%), 각시긴손접시거미(8%) 순으로 나타났다. 또한 4월 중순(7회)에 가장 많은 개체가 채집되었고, 채집이 이루어질수록 거미의 개체수가 증가하는 경향을 보였다.