This study focused on using indirect filtration through riverbeds to produce high-quality drinking water. Data on water quality from a water intake facility(capacity 10,000 m3/day) and nearby rivers were collected over a three-year period. The average intake facility specifications were found to be a specific surface area of 58 balls/m2, a mean particle size of 24 mm, an inflow velocity of 2.2 cm/sec, and a burial depth of 5 m. The water quality improvement rate was assessed as grade Ia, surpassing the adjacent river’s water quality. Correlation analysis showed a weak correlation between opening ratio, Suspended Solid (SS), and Biochemical Oxygen Demand (BOD) compared to total coliforms and fecal coliforms. The correlation coefficient R value of SS was -0.614, BOD was –0.588, total coliforms -0.870, and fecal coliforms -0.958. The R value shows a negative value, which showed that the larger the opening rate, the lower the removal rate of water pollutants. The correlation coefficient R values according to the depth of burial were found to be BOD 0.914, SS-0.124, total coliforms 1.000, and fecal coliforms 0.866. The deeper the burial depth, the higher the removal rate of BOD and microbial groups.

본 연구는 대학에서 미래 일자리 지형변화에 대응하고 신기술분야의 주요 직무를 성공적으로 수행하기 위한 핵심 직무역량 도출을 국내 K대학의 사례를 통해 제시하는데 그 목적이 있다. 이를 위해 신기술분야 로 지능형드론 및 UAM 신기술분야를 선정하고 지역산업 및 K대학 역량 분석 기반으로 핵심직무역량 도출하고자 신기술분야 사례분석-신산업 분야 직무 역량 정의-산업체 전문가 의견 수렴(FGI)-대학 교원 인터뷰 및 설문조사-산업현장성 검증 단계로 연구를 진행하였다. 주요 연구결과는 다음과 같다. 첫째, 신 기술분야의 문헌 및 자료분석을 통해 직무역량을 정의하고 산업 전문가 의견수렴을 통해 직무기초역량 11개, 직무기술역량 43개, 및 초직능적 기술역량 28개 후보군이 도출되었다. 둘째, 관련 대학 교원을 대상 으로 설문조사 결과, 총 7개의 직무기초역량, 9개의 직무기술역량, 8개의 초직능적 기술역량으로 직무역 량 모델을 구성하였다. 셋째, 도출된 직무역량을 토대로 지역 산업 현장 검증을 설문조사를 실시하였고 최종 선정을 위해 각 역량에 대한 Needs Weight를 산출하였다. 그 결과 직무기초역량으로 ‘직업적 윤리 의식, 창의적 사고, 혁신적 사고, 융합적사고, 미래지향적 사고’, 초직능적기술역량은 ‘문제인식 및 문제해 결력, 자기주도성, 탐구정신, 협동 및 기술협력, 의사소통’ , 직무기술역량은 ‘이동체 제어기술, 설계/제작/ 제어능력, 무선통신기술, 센서시스템 활용기술, ICT 기술이해 및 활용’ 등으로 규명되었다. 결과를 토대로 신기술분야의 핵심직무역량 도출을 위한 시사점과 연구의 한계점을 제시하였다.

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.