COVID-19가 전 세계를 강타하면서 각 국가는 대혼란에 빠졌다. 전 세계 화물교역은 80 % 이상이 해상운송을 통해 이루어지고 있어 화물과 여객을 포함한 해상운송업은 COVID-19의 큰 영향을 받는 산업으로 예측되었다. 따라서 본 연구의 목적은 코로나 팬데믹 (Coronavirus Pandemic) 발생 전후로 아시아 주요 항만 컨테이너 항구의 팬데믹 전후 운영효율성을 분석하는 것이다. 항만의 운영효율성을 분석하기 위해서 자료포락분석(DEA)을 이용하였다. 본 연구의 분석 기간은 5년(2016~2020년)으로 2016년, 2017년, 2018년, 2019년을 코로나 이전으로 하고, 2020년을 포스트 코로나 시대로 설정하였다. 또한, 분석 대상으로는 아시아 상위 10개 항구 중 동종 DMU의 DEA 요건을 충족시킨 상하이, 광저우, 선전, 닝보-저우산, 부산 및 싱가포르 총 7개 항구를 선택하였다. DEA의 CCR 및 BCC 모델의 결과는 몇 가지 비효율성이 확인되었음에도 COVID-19 팬데믹 발생 시점에서 몇 개월 이후부터는 전반적으로 운영효율성이 코로나 이전 몇 년 동안보다 상대적으로 높았음을 확인하였다. 하지만 일부 항만 (부산, 광저우)의 경우에는 더욱 나은 운영효율성을 위해서 항만의 규모와 운영의 기술적 능력 등을 제고 할 필요가 있다.

This study examines the Gyeongju Seokguram Grotto restoration project (1961-1962) by architect Kim Chung Up (1922-1988) and introduces the documents he wrote at the time of planning. The study highlights Kim’s Plan attempt to adopt Buckminster Fuller’s idea of the Geodesic Dome, while inheriting the architect Pai Ki Hyung’s previous design plan which was nullified. As Seokguram Grotto’s water leak and deterioration issues have been brought up, the four-times survey was carried out by experts team between 1958 and 1960, under Ministry of Education’s direction. Pai designed an initial restoration plan based on the survey’s result, which was a double-dome structure with a concrete film on the outer periphery as a way to protect Seokguram Grotto in January 1961. However, as drawbacks, such as the heavy load of the concrete dome, and non-installation of entrance hall, have been indicated in the review process, the Cultural Properties Committee rejected the plan. Subsequently, Kim was appointed as the supervisor of the second restoration project. Kim drew up a process management schedule to be implemented from August 1961 to December 1963 and designed the conception plans for the second restoration design. This study analyzes Kim’s Plan by examining sketches, site plans, floor plans, and sections. Kim planned to maintain the idea of the double-dome structure proposed by Pai while applying Buckminster Fuller’s idea of the Geodesic Dome. Kim planned to lighten the dome structure by applying a steel-frame Geodesic Dome so that the dome structure could be supported by its own. The study is expected to reclaim the omitted parts from Seokguram Grotto's historical description and Kim's careers.

PURPOSES : The purpose of this study was to develop the evaluation methodologies for spraying amount and sprayed condition of curing compound based on IoT technology when concrete pavements are constructed. METHODS : To measure the spraying amount of curing compound, a turbine type flowmeter was selected and a number of laboratory experiments were performed to verify the applicability of the selected sensor. To evaluate the uniformity of the sprayed curing compound on the concrete pavement surface, image process technologies were examined using pictures taken from the actual construction sites and from the test specimens. RESULTS : By performing experiments using water and curing compound, the selected flowmeter was verified to properly be applied to measure the spraying amount of curing compound with an acceptable accuracy. By conducting image processing using pictures of the sprayed curing compound on the concrete pavement surface, it was found that the 8 color analysis method was the best to evaluate the uniformity of the sprayed curing compound. CONCLUSIONS : From this study, it was concluded that the spraying amount of curing compound could be accurately measured using a turbine type flowmeter and the uniformity of the sprayed curing compound on the concrete pavement surface could be properly evaluated using an image processing technology.

Global warming affects critical natural resources, one of which is the oceans that occupy 70% of the total cover of the earth. In other words, ocean warming is a subset of global warming which needs to be addressed urgently. Purple laver (pyropia spp.) is one of the most vulnerable items to climate change although it is a major export product of Korean fisheries. The purpose of this study is to analyze the causality of how climate change caused by global warming affects the increase or decrease of PLP (purple laver production). The target area for analysis was set to Maro-hae between Jindo-gun and Haenam-gun. We selected marine environmental factors and meteorologic factors that could affect PLP as variables, as well as co-integration tests to determine long-term balance, and the Granger causticity tests. As a result, PLP and marine environmental factors WT (water temperature), pH, and DO confirmed that long-term equilibrium relationships were established, respectively. However, there is only causality with WT and it is confirmed that there is only a correlation between pH and DO (dissolved oxygen). There was no long-term equilibrium relationship between PLP and HDD (heating degree days) and there is a causal effect that HDD affects PLP; however, it was less clear than that of WT. The relationship between PLP and RF (rainfall), WS (wind speed), SS (percentage of sunshine), and FF (farm facilities) was all balanced in the long term, and causality exists. Based on the results of the analysis, policy proposals were made.

최근 건설시장에 4차 산업혁명기술의 급속한 확산과 도입, 적용이 트랜드로 부각되고 있다. BIM 기술은 4차 산업혁명 기술의 근간을 이루는 다차원 정보체계이다. 이러한 정보기반체계를 활용한 하천분야도 유지관리를 위한 현행화 방안 등 적극적인 연구검토가 되고 있다. 최근 하천 전문가들의 하천분야 BIM도입 효과에 필요성을 반영하여 적극적인 연구와 현행화 작업을 해야 된다. 그리고 첨단기술을 반영한 시설물 유지관리 정보체계를 활성화하고 관리계획 수립 및 운영을 위해서는 다양한 정보체계를 구축하기 위한 도구 및 지원소프트웨어의 개발이 반드시 필요할 것으로 전망된다. 하천시설의 유지운영을 위한 연구로 기본적으로 기존 도면자료를 이용하여 3차원 정보모델을 구축하고 이를 활용한 손상을 점검하고 정보화하며 보수보강을 위한 자료로 활용토록 하는 것이다. 이는 기존 도면방식에 없는 정보체계를 하천시설물을 3D 모델링과 함께 유지관리정보를 속성으로 구축하는 방법을 연구하여 유지운영을 위한 점검, 손상 관리를 보다 효과적이고 활용성이 높은 관리방안을 제시하고자 하였다.

In this study, the flow by impingement at water dust collector with movable nozzle was analyzed by computational fluid technique. The velocity and vorticity of the dust collector were compared by positioning the nozzle to up and down. Also, the mean velocity were compared through three specific locations that were the diffuser inlet, movable nozzle surface and dust collector outlet. It can be checked that the vorticity and velocity magnitude are verified by the fluid solver of Fluent. As the result of this study, the movable nozzle located at 4cm down from initial position of the nozzle shows the great characteristics of vorticity and velocity distribution for dust collection.

Building Information Modeling (BIM) tools have not only increased the use of technology in the design process, but also increased the need for more information standard systems. The object classification system consists of 327 types of construction results obtained from 25 kinds of facilities, 174 types of parts, and 207 types of construction parts. In the previous study, the property classification system was developed into 4 major classifications, 13 middle classifications, 58 small classifications (category), and 333 attribution information of roads and rivers. It is extremely difficult to input the property information according to such extensive object classification. In addition, the development of external applications such as Revit plug-ins has created a need to automate specific and repetitive tasks. Therefore, following the BIM property classification system, an attribute input program was implemented for the system to enhance the productivity and convenience of the BIM users.

용존 6가 우라늄은 다양한 화학종으로 존재하며, 화학종의 분포는 수용액의 pH에 의존한다. 산성 및 중성 근처의 pH 환경 에서는 대표적으로 UO2 2+, UO2OH+, (UO2)2(OH)2 2+, (UO2)3(OH)5 + 화학종이 공존한다. 수용액 속에 비결정성 실리카가 콜로이드 성질의 부유입자 상태로 존재할 때 용존 화학종은 실리카 표면에 쉽게 흡착된다. 이 연구에서는 표면 흡착 화학종의 분 포가 용존 화학종의 분포를 따르는지 조사하였다. 시료의 pH 값이 3.5-7.5인 조건에서 3종의 용존 화학종(UO2 2+, UO2OH+, (UO2)3(OH)5 +)과 2종의 표면 흡착 화학종(≡SiO2UO2, ≡SiO2(UO2)OH‐ 또는 ≡SiO2(UO2)3(OH)5 ‐)의 시간 분해 발광(luminescence) 스펙트럼을 측정하였다. pH 변화에 따른 각 화학종의 스펙트럼 변화 양상을 비교한 결과로 표면 흡착 U(VI) 화학종의 분포는 용존 U(VI) 화학종의 분포와 다르다는 것을 확인하였다.