The design and fabrication of suitable waste forms with high thermal and structural stability are essential for the safe management and disposal of radioactive wastes. In particular, the thermal properties and temperature distribution of waste form containing high heat-generating nuclides such as Cs and Sr can be used to evaluate its thermal stability, but also provide useful information for the design of canisters, storage systems, and repositories. In this study, a new program code-based thermal analysis framework has been developed to facilitate the characterization, design, and optimization of the waste form. Matlab was used as a software development platform because it provides powerful mathematical computation and visualization components such as the partial differential equation (PDE) toolbox for solving heat transfer problems using finite element method, the App Designer for graphical user interface (GUI), and the MATLAB Compiler for sharing MATLAB programs as standalone applications and web applications. The thermal analysis results such as temperature distribution, heat flux, maximum/ minimum temperature, and centerline/surface temperature profile are visualized with graphs and tables. To evaluate the effectiveness of the developed program, several design and optimization studies were carried out for the SrTiO3 waste form, selected as a stable form of strontium nuclide.

This study attempts a comparison between AHP(Analytic Hierarchy Process) in which the importance weight is structured by individual subjective values and regression model with importance weight based on statistical theory in determining the importance weight of casual model. The casual model is designed by for students’ satisfaction with university, and SERVQUAL modeling methodology is applied to derive factors affecting students’ satisfaction with university. By comparison of importance weights for regression model and AHP, the following characteristics are observed. 1) the lower the degree of satisfaction of the factor, the higher the importance weight of AHP, 2) the importance weight of AHP has tendency to decrease as the standard deviation(or p-value) increases. degree of decreases. the second sampling is conducted to double-check the above observations. This study empirically checks that the importance weight of AHP has a relationship with the mean and standard deviation(or p-value) of independence variables, but can not reveal how exactly the relationship is. Further research is needed to clarify the relationship with long-term perspective.

The fabrication of waste forms with high thermal and structural stability is an essential technology for the safe management and disposal of radioactive wastes. In particular, the thermal characteristics of waste forms containing high heat-generating nuclides such as Cs and Sr can be used for the optimized design of the waste form to secure its thermal safety, and they also provide basic design data for the safe management of canisters, storage systems, and repositories. The Korea Atomic Energy Research Institute is actively developing processes and equipment for fabricating various types of high-level wastes into a stable glass or ceramic waste form. In previous research related to the thermal analysis of the waste form, a relatively simple analysis was performed by using the analytic solution of the one-dimensional steady-state heat conduction equation considering the decay heat properties of the waste. As a specific application study, the optimized diameter of the cylindrical glass waste form was proposed by evaluating the centerline temperature of the waste form. In this study, we extended previous research by introducing a more complicated model, and the main results are summarized as follows. First, an analytical solution was derived by applying the temperaturedependent thermal conductivity expressed in the general form of polynomial function to the onedimensional heat conduction problem previously studied. Second, the two-dimensional axisymmetric steady-state heat conduction problem with a more realistic cylinder model with finite length was modeled and solved by using the finite element method via Matlab’s PDE (partial differential equation) toolbox. Third, thermal analysis was performed on the SrTiO3 waste form, selected as a stable form of strontium nuclide, using the developed analytical and numerical methods. The differences in the temperature distribution and computation time were evaluated through a comparative study of both solutions. Although the problem considered in this study could easily be solved by using commercial CFD software such as ANSYS or SolidWorks, a code-based program was developed to facilitate parametric design study in conjunction with optimization algorithms. The analysis results could be used to evaluate the thermal stability of waste form and to optimize the shape and size of the waste form in consideration of the design constraints of storage systems or repositories.

Six Sigma is a philosophy and systematic methodology for quality improvement. It encourages continuous quality improvement efforts to achieve the ideal goal of 6σ. Sigma(σ) is a statistic representing the standard deviation of the normal distribution, and 6σ level means a level where the tolerance of the specification is six times the standard deviation of the process distribution. In terms of the defective rate, the 6σ level achieves the 0.002 defectives per one million units. However, in the field, the 6σ level is used in the sense of achieving 3.4 defects per one million opportunities, which shows a large gap from the 6σ level in the statistical viewpoint. This is because field practitioners accept a 1.5σ shift of the mean of process when calculating the defective rate under sigma level. It said that the acceptance of 1.5σ shift of the mean is from experience, but there is no research or theoretical explanation to support it logically. Although it is a non-scientific explanation based on experience, considering that there has been no objection to the 1.5σ shift for a long time and it is rather accepted, it is judged that there is a reasonable basis for the 1.5σ shift. Therefore, this study tries to find a reasonable explanation through detective power of control chart via the run-rules to the 1.5σ shift empirically recognized by practitioners.

This paper investigates the stress-reducing preventive maintenance model through numerical experiments. The preventive maintenance model is used to analyze the relationship between related conditions and variables to gain insight into the efficient operation of the system when performing preventive maintenance in real-world situations. Various preventive maintenance models have been developed over the past decades and their complexity has increased in recent years. Increasing complexity is essential to reflect reality, but recent models can only be interpreted through numerical experiments. The stress-reducing preventive maintenance is a newly introduced preventive maintenance concept and can only be interpreted numerically due to its complexity, and has received little attention because the concept is unfamiliar. Therefore, for information purposes, this paper investigates the characteristics of the stress-reducing preventive maintenance and the relationship between parameters and variables through numerical experiments. In particular, this paper is focusing on the economic feasibility of stress-reducing preventive maintenance by observing changes in the optimal preventive maintenance period in response to changes in environmental stress and the improvement factor. As a result, when either the environmental stress or the improve effect of stress-reducing preventive maintenance is low, it is not necessary to carry out the stress-reducing preventive maintenance at excessive cost. In addition, it was found that the age reduction model is more economical than the failure rate reduction model.

국립원예특작과학원에서는 2015년 거베라 신품종 ‘Red Velvet’ 을 육성하였다. ‘Red Velvet’은 2007년 10월부터 2008년 2월까지 주홍색 반겹꽃 스탠다드 거베라 ‘Rose’와 적색 반겹꽃 ‘Sabana’를 각각 모본과 부본으로 인공교배하여 얻은 187개체의 교배실생 분리집단으로부터 2008년부터 2015년까지 8년 동안의 개화 및 생육특성검정을 거쳐 선발된 절화용 스탠다드 거베라 품종이다. ‘Red Velvet’은 초세 강건한 갈색 화심의 적색(RHS R45B) 반겹꽃 대륜계통이다. 꽃의 평균 직경은 12.6±0.5cm이고, 내부설상화 및 통상화의 직경은 각각 5.7±0.3cm와 2.8±0.2cm이다. 꽃대는 꽃목직경이 상부 5.4±0.4mm, 중부 7.8±0.7mm 정도로 굵으며, 화경장은 60.0±8.1cm로 길다. 절화수명은 9.8±2.3일로 대조품종과 비슷하며, 연간 채화량은 48.3±4.8본/주로 많은 다수성 품종이다.

해충방제용 미생물 선발을 위해 2018년도에 공원·산림·유기농 근권 토양 87지점을 수집하여 갈색거저리를 이용한 insect-bait법 및 자연조건에서의 감염사충으로부터 곤충병원성 곰팡이를 132균주 분리하였다. 분리된 균주는 점박이응 애, 복숭아혹진딧물에 대한 살충활성 스크리닝을 통하여 각 해충별 살충활성을 보이는 56균주를 선발하였다. 선발된 균주들은 rDNA의 ITS영역을 이용하여 분류동정 하였다. 추가 적용범위 확대를 위해 무잎벌(종령 유충), 거세미나방류 (3~6령 유충)와 같은 지하부 이동성 해충의 방제 가능성을 탐색하기 위해 선발 곤층병원성 곰팡이의 포자 현탁액의 관주처리 방법으로 살충활성을 검정 중이다.

In the past, only one species known for Subtribe Physoderina from Korea. In this study reporting 2 genera and 2 species, Lachnoderma asperum Bates, 1883 and Physodera unicolor Ma, Shi & Liang, 2017, as new record to Korea. Taxonomic key, adult habitus, genitalia and distributional information are provided.

경기지역에 발생하는 돌발 및 남방계 해충의 발생실태 조사결과, 겨울철 경기지역 평균기온이 전년보다 3.7℃, 평년보다는 1.2℃ 낮게 경과함에 따라 포도 재배지 꽃매미 평균 월동난 부화율은 35.6%로 전년 대비 60% 감소하였음. 블루베리 재배지 갈색날개매미충의 평균 월동난 부화율은 26.9%로 전년 대비 50% 감소하였으며, 겨울철 피해가지 제거로 부화약충의 밀도는 매우 낮았음. 저온 적응성이 강한 미국선녀벌레의 경우 6월 중순 안성지역 평야 블루베리에서 약충이 가지당 최대 6.64마리 발견되었으나, 하절기 고온 등으로 성충의 밀도는 크게 감소되었음. 남방계 해충인 볼록총채벌레는 포도 재배지에서 5월 하순부터 발견되기 시작하여 7월 상순부터 급격히 증가하는 양상을 보인 가운데 지역별로는 남부지역(안성), 지대별로는 중산간지 > 산간지 > 평야지 순으로 높은 경향을 보였음.

The objective of this study was to evaluate the effect of treating dairy cattle with exogenous human chorionic gonadotrophin (hCG), five (5) days post artificial insemination (AI) on serum progesterone (P4) concentration and pregnancy rate. In this experiment, five days after AI, cows were assigned randomly to two groups namely: a) treated group (67) which were administrered with 1500 IU hCG (Chorulon) and b) control group (61), which received no treatment. On day 5, 10, 15 and 20 after the artificial insemination, blood samples from a total of 8 cows (4 from each group) were collected and were analyzed for serum P4 concentration. Cows were detected for estrus according to standing heat by visual observation. Cows that were detected still in estrus after days 18-24 were re-inseminated and recorded as not pregnant (open). Pregnancy diagnosis was conducted by ultrasonographic examination and transrectal palpation of the uterus on approximately 60 days in cows that observed to be not in estrus. The conception rate in hCG treated and control groups were 52.5 and 36.1%, respectively. The results proved that there were no significant differences in conception rate between two groups (p=0.0568). However, pregnancy rates were reduced by hCG treatment. Average serum P4 concentrations did not differ between Hcg-treated and control groups on day 5 (0.377 versus 0.375 ng/ml). On day 20 serum P4 concentrations were greater in the treated group compared with the control group (3.085 versus 2.010 ng/ml). The treatment with hCG seemed to increase P4 level compared with the control. In conclusion, the results of this study showed that 1500 IU of hCG administered on 5 day post AI increased conception rate in dairy cows. This was supported by the results on serum P4 concentration which was greater in hCG treated group.