Effects of the extrusion temperature and die angle on the tensile properties of SiCIyAl composites in powder extrusion have been investigated. SiCP/Al composites were extruded at various extrusion temperatures (450, 500, ) under the extrusion ratio of 25 : 1. The ram speed was maintained at 13 cm/min for all the extrusion conditions. The surface of the extruded rod appeared to be smooth without tearing at 450 and 50, whereas it was very rough due to tearing at . It was found that the tensile strength and elongation of the composites extruded at are greater than those of composites extruded at This is due to the easier plastic deformation of composite extruded at , compared with the composites extruded at . The effect of die angle was examined under 20=60, 120, die angles at extrusion temperature of under 25:1 extrusion ratio. The tensile strength of the composites extruded with 20=approved to be higher than that of the composties extruded with 28 : 120 and This is attributable to the higher extrusion pressure, which mixed composite powders could be densely consolidated at elevated temperatures, resulting from high friction force between billet and sliding surface of conical die.

The 4.8GHz formaldehyde absorption line in the dark clouds in M17 and NGC 2024 regions has been mapped. In both nebulae, we detected two H2CO line components. In M17, the 24km S-1 cloud is closely associated with the HII region located in front of the radio continuum source, and the 19km S-1 cloud is associated with the visual dark clouds with a larger extent which are closer to us. The 19km S-1 cloud has a mass motion approaching to the HII region. In both clouds, a velocity gradient from the north-east to the south-west directions is observed. The linewidth has no variation indicating no collapsing motion. In NGC 2024, the 9km S-1 feature is extended along the dark bar in front of the bright nebula and a weak second component at 13km S-1 is confined to the immediate vicinity of the radio source. Indications are that the 9km S-1 cloud is physically associated with the dark bar and the 13km S-1 cloud is located behind the radio source. The angular extent, the column density, and the total mass of the clouds are derived. The radial velocities of other molecular lines observed in these clouds are compared.

실험선 제주 402호의 조종성능을 전속전진중 최대타각으로 전타한 때의 선회권측정과 10˚, 20˚, 30˚Z시험에서 산출된 조종성지수를 분석, 검토한 결과를 요약하면 다음과 같다. 1. 선회종거는 우현선회시가 79.1m로 배의 길이의 약 2.6배였으며, 좌현선회시는 81.4m로서 배의 길이의 약 2.7배였다. 또, 선회경은 배의 길이의 약 2.6배로서 우현선회시가 78.3m로서 좌현선회시 80.4m보다 작았다. 2. 선회권시험시 속력저감율은 0.49였으며, 평균선회각속도는 우현선회시가 4.3˚/sec, 좌현선회시는 4˚/sec이었다. 3. Z시험 결과 over shot angle은 우현전타시가 좌현전타시보다 더 컸으며, 좌우타전타시의 평균값은 10˚Z시험시가 10.5˚, 20˚Z시험시가 20.5˚, 30˚Z시험시가 29.5˚로 다소 큰 편이었다. 4. 10˚, 20˚, 30˚Z시험에서 K' 및 T'의 값은 각각 0.755, 0.566, 0.481 및 3.468, 1.621, 1.547로서 대체적으로 선회성은 대각도 전타 일수록 나쁘거나, 추종성은 대각도 전타 일 수 록 좋았다.

This paper aims at finding out the optimum operating condition to reduce fuel consumption for the training ship Pusan 402 with controllable pitch propeller. For this purpose, this paper examints the variation of ship speed and fuel consumption in accordance with the change of engine revolution and propeller pitch. The results obtained are as follows: 1. When engine revolution is constant, the ship speed sluggishly increases according to the increase of propeller pitch but fuel consumption extremely increases. The higher revolution the engine is, the more remarkable this tendency is. 2. As the engine revolution becomes lower, the fuel consumption per mile decreases. Howt.er = the fuel consumption under the same engine revolution differs according to the propeller pitch. 3. Specific fuel consumption is uniformed about 180g/ps.h at any case of load. 4. Among the various operating conditions which yield the same ship speed, fuel consumption lowers in the case of lower engine revolution and larger propeller pitch.

The maneuverabilities of the M. S. PUSAN 402 are studied, based on maneuvering indices and the data obtained from her Z test. The results obtained are summarized as follows: 1. The maneuvering indices K' and T' of the M. S. PUSAN 402 are 1. 490, 1.030 at 10˚ Z test and 2.644, 1.153 at 20˚ Z test and 3.382. 1. 027 at 30˚ Z test respectively. The above calculated values K', T' showed that her maneuverabilities are more increased when the rudder is used to large angle than to smaIl angle. 2. As her maneuvering indices K' and T' at 10˚ Z test are higher than the standard maneuvering indices of fishing boats, her turning ability was found to be higher but her obeying ability lower. 3. When the M. S. PUSAN 402 took a turn at her 10˚ test, running distance was about 8.4 times her own length and didn't exceed the standard maneuvering distance, 5 to 11 times ship's own length, therefore she was considered to have good maneuverabilities syntheticaIly.

NGC 7023 have been observed in ^(12)CO and ^(13)CO (J=1→ 0) molecular line emissions. It possesses bipolar molecular outflows which are moving out both eastward and westward in Right Ascension with a velocity range of ±9 ㎞s^(-1) with an inclination of ∼80° The mass loss rate is ∼10^(-5)M◎_(yr)^(-1) with an assumed stellar wind velocity of ∼100㎞s^(-1); the dynamical age of this outflow is ∼5.5×10⁴ years. The bipolar molecular outflows would be collimated by the molecular disk surrounding HD 200775, which is explained by either the velocity gradient of ∼0.25 ㎞s^(-1) are min^(-1) in the position-velocity map of ^(12)CO along the Declination or the peak temperature maps of both ^(12)CO and ^(12)CO. The outflows also yield high density regions at their ends, producing the region of the low mass star formation.

The Colloid Formation and Migration (CFM) international joint research initiative continues as a part of the GTS’s Radionuclide Retardation Programme, which has been in progress since 1984. This project focuses on examining the formation of colloids from a bentonite-engineered barrier system and exploring how these colloids impact the migration of radionuclides in fractured host rock when subjected to advective flow. Phase 1 of the project was launched in 2004 and concluded in early 2008, focusing on preliminary studies related to in-situ boundary conditions, predicting models, and supplementary lab works. Following that, Phase 2 spanned from 2008 to 2013 and aimed at fortifying the field setup by adding three new monitoring boreholes and suitable instrumentation in both the boreholes and tunnel. This phase also tested the system’s resilience while mapping the flow domain. Phase 3 kicked off in January 2014 and extended until December 2018. During this period, the Long-term In-situ Test (LIT) was introduced in May 2014, featuring a set of compacted bentonite rings laced with radionuclide tracers. These were placed in a borehole to serve as a colloid and radionuclide source. CFM Phase 4 initiative commenced in January 2019, marking the successful deployment of the i-BET (In-situ Bentonite Erosion Test). This project component involves placing approximately 50 kg of compacted bentonite in a natural water-conducting shear zone. Korea Atomic Energy Research Institute (KAERI) joined CFM in 2008 to examine the behavior of colloid generation and migration with radionuclides in the Underground Research Laboratory. The fourth phase of the CFM project was also scheduled to include a post-mortem evaluation of the LIT and additional tracer experiments in the well-mapped MI shear zone. This study aims to provide an interim update on the ongoing i-BET, a key component of Phase 4 of the CFM project. We will also discuss the current status of the post-mortem analysis for the LIT experiment. In addition, we will outline plans for the forthcoming Phase VI of the project. These plans will continue to advance our understanding of radionuclide migration and the influence of bentonite-based disposal systems.

본 논문은 2022학년도 교양 음악 과목의 현황 및 성격을 파악하기 위하여 서울 소재 12개 대 학교를 선정하여 개설 현황과 강의개요의 내용을 분석하였다. 개설 현황 분석에 있어서는 개설 과목의 수와 주제를 분석했으며, 특히 자료가 일반인에게 공개되어 있는 10개 대학의 경우에는 2008학년도 자료와 비교하여 시대적 추이를 가늠하고자 했다. 개설 과목이 현저히 증가한 대학의 경우에는 교양교육을 전담하는 기관 또는 주체가 뚜렷함을 보여 주었으며, 개설 과목의 성격 역시 담당 기관 및 주체의 운영 방식과 직접적인 연관이 있음을 알 수 있었다. 교양 음악 과목의 주제 를 분석한 결과, 서양음악이 거의 절반을 차지하는 반면, 한국음악, 대중음악, 융복합의 순서로 그 나머지를 구성하며 세계음악은 미미한 것으로 나타났다. 슐러의 ‘독립적 음악 능력’에 기초하여 과목의 성격을 분류한 결과는 현재 이론적인 측면이 76%를 차지함으로써 연주와 창조의 측면이 부족한 것으로 분석되었다. 한편, 강의 개요의 내용을 요르겐슨의 다섯 가지 음악 교육철학에 기 초하여 질적연구 소프트웨어 엔비보로 코딩 분석하였다. 이때, 강의의 성격 및 강의개요서 서술방 식에 따라 분석 결과가 상이하게 나타날 수 있으며, 실질적인 강의의 내용과 동일하지 않을 수 있 음을 한계로 밝힌다. 연구의 결과, 지식과 가치, 특히 음악적 지식과 가치를 가장 중요하게 다루 고 있으며, 다음으로 실기 능력의 전수, 개인의 경험과 표현의 증대, 사회적 기여, 다양한 문화의 유지의 순서로 중요하게 여기는 것으로 나타났다.

The Korea Laboratory Accreditation Scheme (KOLAS) is the national accreditation body responsible for providing accreditation services to testing and calibration laboratories. The primary objective of KOLAS is to promote the quality and reliability of laboratory testing by providing nationally and internationally recognized accreditation services. Laboratories accredited by KOLAS are required to meet rigorous international standards set by the International Organization for Standardization (ISO) and are subject to regular assessments to ensure ongoing compliance with the standards. KOLAS accreditation is highly regarded both domestically and internationally, and is recognized for providing high-quality and reliable testing services. The nuclear analysis laboratory at KINAC has been working to establish a quality management system to ensure the external reliability of analytical results and to secure its position as an authorized testing agency. To achieve this, a detailed manual and procedure for nuclear material analysis were developed to conform to the international standards of ISO/IEC 17025. This study presents the preparation process for establishing the management system, focusing on meeting technical and quality requirements for the implementation of the ISO/IEC 17025 standard in the KINAC nuclear analysis laboratory, specifically in the field of chemical testing (dosimetry, radioactive, and neutron measurement subcategories). The preparation process involved two tracks. The first track focused on satisfying technical requirements, with Thermal Ionization Mass Spectrometer (TIMS) and Inductively Coupled Plasma-Mass Spectrometer (ICP-MS) selected as the major equipment for analysis. Analytical methods for determining isotope ratios and concentrations of nuclear materials were determined, and technical qualification was ensured through participation in proficiency test programs, inter-experimenter comparison tests, and uncertainty reports. The second track focused on developing the quality system, including quality manuals, procedures, and guidelines based on the requirements of the ISO/IEC 17025 standard. Various implementation documents were produced during the six-month pilot period, in accordance with the three levels of documents required by the standard. Implementation of ISO/IEC 17025 is expected to have a systematic quality management process for the analysis lab’s operations and to increase confidence in KINAC’s nuclear analysis.

According to the ROK-IAEA Comprehensive Safeguards Agreement (CSA), the ROK submits inventory change reports (ICRs), physical inventory lists (PILs), and material balance reports (MBRs). Suppose inventory changes occur in each material balance area (MBA). In that case, the facility operators prepare ICRs monthly, conduct physical inventory taking (PIT) every 12 to 18 months, and submit PILs and MBRs to KINAC. KINAC reviews ICR presented by the facility operators, submits it to the IAEA, and reports it to the Nuclear Safety and Security Commission (NSSC). Various methods have been prepared and implemented to minimize errors in reviewing the accounting reports submitted by the facility operators. Accordingly, this paper analyzes the mistakes in the accounting reports that occurred over the past two years and proposed methods to improve them. The basis for carrying out the accounting reports is stipulated mainly in the CSA and the Nuclear Safety Act. First, Article 63 of the CSA describes the rationale for submitting the accounting reports, and the details are described in detail in the subsidiary arrangement. Article 98 of the Nuclear Safety Act stipulates information related to accounting reports, and details are described in the regulations on reporting internationally regulated materials, etc., of the NSSC Notice No. 2017-84. Among the accounting reports submitted in 2021, a total of 36 errors were confirmed. There were ten errors related to inventory changes, followed by six errors in the material balance period (MBP) in the header information. There were four cases of spacing, weight mismatch, and overdue errors, and the rest were related to grammar errors. There were a total of 30 errors in the accounting reports identified in 2022. MBP errors of header information, which occurred the second most in 2021, was the highest with nine, followed by six inventory change errors and five weight mismatch and overdue errors, respectively. Compared to 2021, the total number of errors has decreased by about six, which is interpreted as the result of outreach activities through accounting reporting workshops and nuclear control education conducted by KINAC. Accounting reporting is the most critical part of the Nuclear Material Accounting and Control (NMAC) system. Efforts to check errors in accounting reports and improve report quality through outreach activities could be confirmed by the statistics of the two years analyzed earlier. In the future, if the reporting program used by the facility operators is improved to minimize errors and manage the accounting reporting system through continuous maintenance work, the quality of the accounting reports will be upgraded to the next level.

This study investigated the effect of May 31, 2022 Miryang wildfire on fine particle concentrations in Busan and Gimhae, which are neighboring urban areas. In addition, fine particle characteristics and air pollution concentrations were investigated in Miryang, where haze occurred. The Miryang city wildfire that occurred on May 31, 2022, at 0925 LST, was driven by strong north winds and increased fine particle concentrations in Dongsangdong and Jangyoodong, Gimhae City, which are approximately 35 km to the southeast and south, respectively, of the wildfire occurrence site. Furthermore, the fine particle concentration in Myeongjidong, which is approximately 50 km south-southeast of the wildfire site, exhibited a temporary increase at 1400 LST owing to the effects of wildfire smoke. On the morning of June 1, the day after the fire, the Miryang area had very bad visibility because of the smoke from the fire. Therefore the PM10 and PM2.5 concentrations in Naeildong, 3 km south of the wildfire site, were 276 μg/㎥ and 222 μg/㎥, respectively, at 1200 LST. In addition, the gases O3, CO, and SO2 showed high concentrations at the time of haze generation. This study provides insights into policy making in response to the rapid increase in fine dust when wildfire occurs near cities.

This study investigated the effect of volcanic materials that erupted from the Nishinoshima volcano, Japan, 1,300 km southeast of the Busan area at the end of July 2020, on the fine particle concentration in the Busan area. Backward trajectory analysis from the HYSPLIT model showed that the air parcel from the Nishinoshima volcano turned clockwise along the edge of the North Pacific high pressure and reached the Busan area. From August 4 to August 5, 2020, the concentration of PM10 and PM2.5 in Busan started to increase rapidly from 1000 LST on August 4, and showed a high concentration for approximately 13 hours until 2400 LST. The PM2.5/PM10 ratio showed a relatively high value of 0.7 or more, and the SO2 concentration also showed a high value at the time when the PM10 and PM2.5 concentrations were relatively high. The SO4 2- concentration in PM2.5 in Busan showed a similar trend to the change in PM10 and PM2.5 concentrations. It rose sharply from 1300 LST on August 4, at the time where it was expected to have been affected by the Nishinoshima Volcano. This study has shown that the occurrence of high concentration fine particle in Busan in summer has the potential to affect Korea not only due to anthropogenic factors but also from natural causes such as volcanic eruptions in Japan.