The fuel fabrication facility has been built and is being operated by KAERI since licensing research reactor fuel fabrication in 2004. After almost 20 years of operation, outdated equipment for fabrication or inspection has been replaced by automated, digitalized ones to assure a higher quality of nuclear fuels. However, the generation of a large amount of radioactive waste is another concern for the replacement in terms of its volume and various types of it that should be categorized before disposal. The regulatory body, NSSC (Nuclear Safety and Security Commission) released a notice related to the classification of radioactive wastes, and most accessory equipment can be classified into the clearance levels, called self-disposal waste. In this study, the practice of self-disposal of metal radioactive waste is carried out to reduce its volume and downgrade its radioactivity. For metal radioactive waste, which is expected to occupy the most amount, analysis status and legal limitations were performed as follows: First, the disposal plan was established after an investigation of the use history for equipment. Second, those were classified by types of materials, and their surface radio-contamination was measured for checking self-disposable or not. After collecting data, the plan for the self-disposal was written and submitted to the Korea Institute of Nuclear Safety (KINS) for approval.

One of the promising candidates for accident-tolerant fuel (ATF), a ceramic microcell fuel, which can be distinguished by an unusual cell-like microstructure (UO2 grain cell surrounded by a doped oxide cell wall), is being developed. This study deals with the microstructural observation of the constituent phases and the wetting behaviors of the cell wall materials in three kinds of ceramic microcell UO2 pellets: Si-Ti-O (STO), Si-Cr-O (SCO), and Al-Si-Ti-O (ASTO). The chemical and physical states of the cell wall materials are estimated by HSC Chemistry and confirmed by experiment to be mixtures of Si-O and Ti-O for the STO; Si-O and Cr-O for SCO; and Si-O, Ti-O, and Al-Si-O for the ASTO. From their morphology at triple junctions, UO2 grains appear to be wet by the Si-O or Al-Si-O rather than other oxides, providing a benefit on the capture-ability of the ceramic microcell cell wall. The wetting behavior can be explained by the relationships between the interface energy and the contact angle.

사고저항성 핵연료의 일환으로 UO2 입자가 세라믹 셀 벽으로 둘러싸인 미세구조를 갖는 세라믹 미소셀 UO2 소결체를 개발 중이다. 이는 핵분열생성물들을 UO2 펠렛 내에 포집하여 펠렛 외부로의 방출을 저감함으로써 봉내압 상승을 완화하고 응력부식균열 발생률을 낮춘다. 생성량이나 방사능 측면에서 위험한 핵분열생성물 중 하나로 여겨지는 세슘은 세라믹 미소셀 소결체 내에서 셀 물질과 화학반응 하여 포집될 수 있다. 따라서, 세슘 포집능은 해당 화학반응의 열역학적, 속도론적 특성에 의해 결정된다. 역으로, 미소셀 소결체의 조성설계 시 해당 반응에 대한 열역학적 예측이 필수적이다. 본 연구는 세라믹 현재 개발 중인 여러 미소셀 조성(Si-Ti-O, Si-Cr-O, Si-Al-O)에 대해 세슘의 포집능을 평가하는 열역학적 계산을 다룬다. 계 산에 앞서 먼저 HSC Chemistry를 이용해 세슘과 셀 물질의 물리/화학적 상태를 정의한 후, LWR 정상운전 모사환경에서 계 산된 세슘포텐셜(ΔGCs)과 산소포텐셜(ΔG02)에 근거하여 세슘포집 반응성을 평가하였다. 계산 결과에 근거하면, 세슘 포집 반응은 상기 모든 조성에서 자발적일 것으로 예상되며 이로써 조성설계의 근거를 제시함과 동시에 세슘의 포집능을 평가하는 효과적인 방법을 제공한다.

Insect pollinators of the endanger orchid Cypripedium japonicum were surveyed and identified during two years, as a part of a conservation project of the orchid at Jukyeup-san and Hwaak-san (Mt.), South Korea. In total 40 individuals of 16 species in 4 families were identified. The dominant family was Halictidae, and Lasioglossum exiliceps Vachal visited the most frequently C. japonicum during the surveys. The average visiting frequency was 2.5 individuals per hour and the highest 4.3, from 12:00 – 13:00 in a day. After 15:00 insects did not visit the flowers at all. However, all of the visiting insects were found to not carry a pollinium or pollens of the orchard on their bodies; pollen carryover by any of the visiting insects did not occur at all. The orchid seems to require certain pollinators in particular body thickness due to its unique pollination mechanism. The orchid has two exit route openings, around 1 cm in diametre, where the entrapped insects can exit and an anther is situated just in front of each opening. It was inferred that a pollen carrier should be around 1 cm in body thickness. Therefore, the candidate species as the proper pollen carriers can be Tetralonia nipponensis Perez, Xylocopa appendiculata circumvolans Smith and Bombus consobrinus Dahlbom among the surveyed visitors.

Achondroplasia is associated with craniofacial abnormality, musculoskeletal deformations, and respiratory, cardiovascular abnormalities. So, anesthetic management is one of clinical challenges. Herein, we report and discuss a case of achondroplastic patient underwent osteosynthesis for femur fracture, which was chosen on the base of patient’s anatomical and physiological characteristics. The patient had thoracolumbar kyphosis (21.8°), previous spine surgery, short neck, obstructive sleep apnea, and mild cervical limitation. Intubation was conducted with smaller cuffed endotracheal tube under videolaryngoscope guidance. Mechanical ventilation was applied with volume control mode, using a tidal volume of 8-10 ml/kg without positive end-expiratory pressure. The patient was supine after placing support under shoulders and head during intubation and surgery. Intraoperative body temperature was maintained using air-forced waring blanket. Complete and careful preoperative evaluation is absolutely important to select the appropriate anesthetic method. Ideal anesthetic management in each case should be based on an individualized decision-making.

Hartmann’s procedure is most often used if immediate anastomosis is not feasible and considered very high risk of anastomotic leakage. The reversal of Hartmann operation has a significant benefit in patient's quality of life, but there are disadvantages because it is procedure of a high degree of complexity. For reversal of Hartmann operation to be truly beneficial, morbidity rate should be reasonable. The aim of this study is therefore to review clinical outcomes of the conversion of Hartmann procedure and define the complication rate of reversal of Hartmann operation in a contemporary practice. Patients undergoing an elective reversal of Hartmann’s procedure at Chosun University Hospital between January 2011 and December 2016 were included in our analysis, and the medical records were retrospectively reviewed. Total 70 patients underwent Hartmann reversal during this period. There were 33 men (47.1%) and the mean age was 67.7±14.5. The most frequent indications for Hartmann’s procedure were complicated diverticulitis in 37 patients (52.9%). Major morbidity rate was 14.3 % (10 patients), anastomotic leakage rate of 4.3% and mortality rate was 2.9% (2 patients). The most common complication was wound infection (25.7%). Univariate analysis demonstrated that there were no statistically significant variables. This study demonstrates that patients who underwent reversal of their Hartmann’s operation did not have increased postoperative morbidity based on advanced age, higher ASA score, presence of multiple comorbidities, type of operation, and longer operation time.