PURPOSES : The process of extracting and recovering an asphalt binder from an asphalt mixture is harmful to the human body and can affect the properties of the asphalt binder owing to the presence of residual solvent quantities. This study was conducted to determine the properties of aged asphalt binders based on rejuvenator content without extracting and recovering the asphalt binders using RAP mortar. METHODS : After extracting and recovering aged binders from waste asphalt, a rejuvenator was added at a certain rate to evaluate the physical and rheological properties of the binder based on the added amount. RESULTS : When the rejuvenator content was greater than necessary, the absolute viscosity was not properly measured owing to the behavior of the rejuvenator. The phase angle was measured to be almost 90°, thus indicating that it acted as a liquid . In addition, the shear strain and nonrecovery compliance also increased significantly. CONCLUSIONS : If an excess rejuvenator quantity was added to the aged binder, the absolute viscosity was not properly measured, the phase angle was measured to be almost 90°, and the shear strain increased significantly. It is also necessary to conduct the same tests on different types of RAPs to ensure that the results of this study are reasonable.

This study aims to present a method to evaluate the relative risk of failure due to liquefaction of domestic small to medium-sized earthfill dams with a height of less than 15 m, which has little information on geotechnical properties. Based on the results of previous researches, a series of methods and procedures for estimating the probability of dam failure due to liquefaction, which calculates the probability of liquefaction occurrence of the dam body, the amount of settlement at the dam crest according to the estimation of the residual strength of the dam after liquefaction, the overtopping depth determined from the amount of settlement at the dam crest, and the probability of failure of the dam due to overtopping was explicitly presented. To this end, representative properties essential for estimating the probability of failure due to the liquefaction of small to medium-sized earthfill dams were presented. Since it is almost impossible to directly determine these representative properties for each of the target dams because it is almost impossible to obtain geotechnical property information, they were estimated and determined from the results of field and laboratory tests conducted on existing small to medium-sized earthfill dams in previous researches. The method and procedure presented in this study were applied to 12 earthfill dams on a trial basis, and the liquefaction failure probability was calculated. The analysis of the calculation results confirmed that the representative properties were reasonable and that the overall evaluation procedure and method were effective.

The need for an intelligent information-based ship accident prevention and control system for various marine accidents is very clearly emerging. As it is a variety of marine accidents, the causes are diverse. Therefore, it can be said that it is very important to prevent these marine accidents and their causes in advance. Therefore, a study was conducted on an intelligent information-based ship safety management decision support system that provides information necessary for decision-making at sea and land through an integrated management device for ships that informs safety-related risks in real-time ship operation. In the future, we intend to pursue the development of a system that can aim for safer and more economical ship operation by linking it to navigation instruments through the evaluation and analysis of AI, IoT, and big data.

Failure diagnoses on large diesel engine are commonly detected when a deviation or fluctuation in its temperature, pressure, vibration or noise set parameter limits arises. These parameters can be easily monitored and can provide information of the engine’s present state depending on external environment and operating conditions. On the other hand, long term monitoring and condition management can be interfaced into the engine’s existing operating system. The approach is seen to keep track of monitored machines’ status using resonance and vibration amplitude. In particular, these signals will be able to identify complex vibration characteristic pertaining to such as engine torque output and support mounts. In this paper, a basic research for large diesel engine diagnosis was carried-out. The failure diagnosis collects and monitors the vibration state time history by using various vibration signals with reference to ISO 13373-1. Further, this monitoring system in the field of large diesel engines has not been applied practically and the results of this study are presented herein.

The object of this study is to evaluate whether the means of egress of Jechon Sports Center and Miryang Sejong Hospital, where massive fire human casualties occurred in 2017 and 2018 respectively, comply with NFPA 101(Life Safety Code), and to suggest the need for supplementation of domestic means of egress regulations. The study evaluated the number and arrangement of the means of egress, travel distance, common path of travel, dead end and discharge from exit for each building by applying the means of egress regulations of NFPA 101. As a result of the evaluation through NFPA 101, the travel distance was appropriate, but some of the other items except for the travel distance did not meet NFPA 101. The regulations that need to be supplemented are 1)occupant load calculation 2)egress capacity calculation 3)continuous concept of means of egress 4)concept of common path of travel. It is especially necessary to revise the requirement for fire door of the evacuation floor(normal 1st floor) of the stairwell in case of below the five story building.

이 논문의 목적은 기독공동체가 본질적 목회를 추구하면서 건강한 성장을 이루는 성경적 목회 패러다임을 도출하는 것이다. 이에 이 연구는 교회 운동의 두 축인 교회성장학(church growth)과 선교적 교회론(missional ecclesiology)을 살핀다. 연구의 진행은 두 이론을 대표할 만한 학자들의 견해를 살핀 다음 다시 두 이론의 공통점과 합일점을 이해하여 상호보완적으로 결합한다. 이는 초기 교회성장학의 선교 정신을 재이해하면서 선교적 교회론과의 협력을 통해 본질적 교회성장을 추구하기 위해서다. 또한, 교회성장과 선교(또는 통전적 선교)의 관계를 동일선상에서 해석하는 ‘통전사적 궤도’(holistichistorical Orbit)의 관점 때문이다. 다시 말해, 하나님의 선교는 구속 사적(redemptive-historical)이고 약속사적(promise-historical) 인 선교의 양방향을 모두 아우르기 때문에 궁극적으로 교회성장과 선교는 우선성의 논의주제가 아니라 ‘하나님 나라’(Kingdom of God) 를 위한 절대적이고 유기적인 동역 관계라는 의미다. 이런 관점에서 이 논문은 두 이론의 ‘통섭’을 중시하고 이로 인한 교회성장을 ‘통섭적 교회성장’(church growth of consilience)이라고 칭한다. 이런 측면 에서 이 연구는 중도주의적이고 연결주의적이며, 모이고 흩어지는 교회론적 균형을 통해 ‘참된 교회의 성장’을 추구한다.

This study analyzes the importance and implementation of countermeasures to reduce safety accidents that may occur during fishing in coastal gillnet fishing. Safety accidents that may occur in coastal gillnet fishing were classified into 56 measurement items in six areas: slips and trips, contact with machinery, falls, struck by object, musculoskeletal symptoms, and electrical shock. 35 fishermen belonging to coastal gillnet associations in Tongyeong and Namhae were selected as samples, and the importance and implementation of the proposed measurement items were investigated in the field. In addition, the results were evaluated visually by IPA analysis. As a result of the analysis, the importance of struck by object was the highest, and the implementation of slips and trips was the highest. On the other hand, prevention of musculoskeletal damage was found to be the lowest in both importance and implementation. The area with the most significant difference in importance and implementation by the classified area for measurement items was struck by object, and the area with the minor difference was slips and trips. Among the measurement items, the importance is highly recognized, but there are items with low implementation. To improve their level of implementation, countermeasures such as continuous education, economic support, and structural change of fishing boats should be prepared; moreover, policy support activities for implementation should be carried out.

본 연구는 최근 다시금 논란이 되는 복지 사각지대 문제를 다룬다. 먼 저, 현재 복지 사각지대 해소를 위해 어떤 제도들이 있는지 확인하고, 현 제도의 한계가 무엇인지를 확인한다. 그리고 현 제도의 한계를 바탕으로 제도적 개선점이 무엇인지를 고민해보고자 한다. 논의는 크게 세 측면에 서 이루어진다. 먼저 저소득층 대상 복지제도의 핵심인 국민기초생활보 장제도의 개선 방향이다. 두 번째는 복지 사각지대 발굴체계 개선에 관 한 논의이다. 마지막으로, 기존 제도가 아닌 대안적 사회보장제도에 관한 논의를 짧게 소개하고자 한다. 이러한 논의를 바탕으로 앞으로 복지 사 각지대 문제 개선을 위한 과정에 이바지하고자 한다.

선박용 엔진에서 배출되는 배기가스에는 다량의 수분과 미세먼지를 포함하고 있다. 미세먼지에는 여과성 미세먼지와 배기 배 출 후 액상으로 변화하는 응축성 미세먼지가 포함되어 있으며 배출 전에 걸러지는 고체상 미세먼지보다 응축성 미세먼지가 더 많은 것으 로 보고되고 있다. 본 연구에서는 배기가스의 배기열과 수분을 회수하고 응축성 미세먼지를 제거하기 위한 실험장치를 실험실 내의 가스 보일러 배기가스를 이용하여 테스트 하였다. 배기가스는 1차적으로 냉각방식으로 수분과 응축성 미세먼지가 제거되고 2차적으로 흡수제 방식에 의해 추가적으로 수분이 제거되었다. 상대습도 측정에 의한 배기가스 수분 제거율을 계산하면 1단계 배기냉각 방식으로 73%, 2단 계 흡수제 방식으로 90% 제거되는 것으로 측정되었다. 이 과정에서 응축성 미세먼지는 80~90% 제거되는 것으로 측정되었다. 개발 시스템 에 의해 회수된 열은 공정열로 활용할 수 있으며, 회수된 물은 수처리 과정을 통해 공정수로 활용할 수 있다. 또한 현재 관리 규제가 되고 있지 않지만 미세먼지의 주요 원인인 응축성 미세먼지를 효과적으로 제거할 수 있을 것으로 기대된다.