정서표상에 대한 논의 중 첫 번째는 정서가 차원에서의 정서표상, 두 번째는 감각양상에 따른 정서표상을 설명하는 것이 다. 선행연구에서는 정서표상을 설명하기 위해 정서가 모델(부호 정서가, 비부호 정서가), 감각양상에 따른 정서표상 모델 (감각보편성, 감각특징성)들이 제시되었다. 본 연구에서는 최근에 등장한 ASMR을 이용하여 기존 연구에서 제시된 모델들 을 비교하여 어떠한 모델이 정서표상을 잘 설명하는지 확인하고자 하였다. 본 연구에서 사용한 자료는 Kim & Kim(2022) 에서 수집한 3개의 정서유형(부정, 중립, 긍정) 및 2개의 감각양상(청각, 시청각)으로 구분된 ASMR 자극에 대한 정서평정 자료를 사용하였다. 이후, 해당 자료에 대한 다차원척도법, 표상 유사성 분석 및 이원 변량분석, 다중회귀분석 및 이원 변량 분석을 실시하였다. 다차원척도법 결과, 비부호 정서가에 비해 부호 정서가, 감각특징성에 비해 감각보편성에서 자극의 정 서유형 간 구분이 잘 이루어졌다. 다차원척도법 결과와 유사하게, 표상 유사성 분석 및 다중회귀분석 결과 또한 비부호 정서가에 비해 부호 정서가, 감각특징성에 비해 감각보편성이 유의하게 정서표상을 잘 설명하였다. 이러한 결과는 정서가 모델 중 1차원의 양극단에 긍정과 부정이 위치하는 모델이 ASMR에 대한 정서표상을 잘 설명하며, 감각양상과 상관없이 정서표상이 일관적임을 시사한다.

Modular construction is an economical and efficient construction that reduces time and costs by manufacturing units in factories and constructing them on site. Currently, the demand for modular construction is increasing not only abroad but also domestically. As the demand for modular construction increases, a lot of development and research on connections between modular units are being conducted. Connections between modular units should be quick and simple to assemble when assembling units on site, and should be in a form that allows each unit to be connected regardless of direction. In addition, it must be able to exert sufficient strength against external loads. In this study, a connection between modular units using connecting steel plates and bolts was proposed, and the nonlinear behavior of the connection to external lateral force was analyzed through finite element analysis, and resistance performance was evaluated.

Reinforcement learning (RL) is widely applied to various engineering fields. Especially, RL has shown successful performance for control problems, such as vehicles, robotics, and active structural control system. However, little research on application of RL to optimal structural design has conducted to date. In this study, the possibility of application of RL to structural design of reinforced concrete (RC) beam was investigated. The example of RC beam structural design problem introduced in previous study was used for comparative study. Deep q-network (DQN) is a famous RL algorithm presenting good performance in the discrete action space and thus it was used in this study. The action of DQN agent is required to represent design variables of RC beam. However, the number of design variables of RC beam is too many to represent by the action of conventional DQN. To solve this problem, multi-agent DQN was used in this study. For more effective reinforcement learning process, DDQN (Double Q-Learning) that is an advanced version of a conventional DQN was employed. The multi-agent of DDQN was trained for optimal structural design of RC beam to satisfy American Concrete Institute (318) without any hand-labeled dataset. Five agents of DDQN provides actions for beam with, beam depth, main rebar size, number of main rebar, and shear stirrup size, respectively. Five agents of DDQN were trained for 10,000 episodes and the performance of the multi-agent of DDQN was evaluated with 100 test design cases. This study shows that the multi-agent DDQN algorithm can provide successfully structural design results of RC beam.

한반도에 분포하는 백악기 육성퇴적층 중 경상누층군 퇴적물의 기원지 조성과 조구조 환경에 대한 연구는 활발 하게 이루어진 반면에 그 외 퇴적층에 대한 사암의 암석학적 연구는 아직 부족하다. 본 연구에서는 부산 기장군 일광 읍 신평리 해안가 일대에 분포하는 백악기 이천리층의 사암을 대상으로 암석기재학적 연구를 수행하여 기원지의 특성 에 대한 예비 해석 결과를 보고하였다. 이천리층 사암은 미성숙한 조성과 조직을 나타내며 백악기 당시 유라시아 동쪽 연변부에서 일어난 고태평양판의 섭입에 의해 융기하여 발달한 화산호로부터 단시간에 퇴적물이 생성되어 운반된 것으 로 보인다. 그리고 사암 내 부수광물로 크롬 첨정석이 다수 관찰되는데, 이는 기원지에 초고철질암이 분포하였음을 의 미한다. 향후 추가 연구를 바탕으로 크롬 첨정석 기원암의 형성 환경 뿐만 아니라 이천리층 퇴적 당시 경상분지 동남 부의 조구조 환경에 대한 해석과 경상누층군과의 층서 대비가 가능할 것으로 기대된다.

해양을 이용하려는 수요자 증가에 따라, 해양공간을 합리적으로 배분하기 위해 해양공간계획(Marine Spatial Planning)제도가 도 입되었다. 이 중 어업활동보호구역은 수산자원보호 등 어업활동 보호를 위해 지정되었다. 그러나, 어업활동보호구역을 주로 항해하는 어 선은 우리나라에서 발생하는 해양사고의 약 70 %를 차지할 정도로 위험에 노출되어 관리가 필요하다. 본 연구의 목적은 어업활동보호구 역 내 어선 통항 안전 확보를 위해 어업활동보호구역과 항만·항행구역에서 발생하는 해양사고를 분석하는 것이다. 이를 위해 해양용도구 역의 교통량을 조사하고 선종별, 사고 유형별, 톤수별, 사고원인별, 인명피해별로 해양사고를 조사하였다. 분석 결과 각 유형별 단위 면적 당 해양사고는 대부분 항만·항행구역에서 더 많이 발생하였으나 전체적으로 발생한 해양사고는 어업활동보호구역이 높았다. 특히 인명사 고가 많이 발생하여 통항 안전관리가 필요한 것으로 식별되었다.

The objective of this study is to evaluate the antioxidant components, elastase inhibition activities, and melanin synthesis rates of Korean traditional Actinidia (Actinidia arguta) fruits and leaves depending on the ethanol extraction concentrations. The total polyphenol content was the highest in the 50% ethanol extract of both fruits and leaves, with values of 634.1 mg GAE/100 g and 3,985.2 mg GAE/100 g, respectively. The total flavonoid content was the highest in the fruit 90% extract and leaf 50% extract at 191.9 mg/100 g and 2655.6 mg/100 g, respectively. The vitamin C content was the highest in the 50% extract of leaves at 2990.3 mg/100 g. Elastase inhibition was the highest at 56.9% in the leaf 50% extract at a concentration of 1,000 μg/mL. Melanin synthesis inhibition showed the highest melanin synthesis inhibitory effect among the extracts, as the leaf 50% extract showed an inhibitory rate of 65% or more. Therefore, the antioxidant components, elastase inhibition activities, and melanin synthesis inhibitory rate were better in leaves than in fruits. The leaf 50% extract was particularly the best among the extracts. Korean traditional Actinidia leaves can be considered as potential sources for new functional materials.

본 연구는 후박나무 용기묘를 대상으로 전광, 35%, 55%, 75% 차광수준에 따른 생장 특성 및 생리적 반응을 알아보고자 실시하였다. 후박나무 묘목은 차광 시 상대적으로 지상부의 생장특성을 보여주는 지표들이 높은 경향을 보였으며, 전광에서는 뿌리와 관련된 지표인 뿌리건중비, 뿌리생장에 서 유의적으로 높은 경향을 보였다. 또한, 전광에서의 낮은 광보상점과 높은 순양자수율은 이미 후박나무가 내음성을 가지고 있고, 광이 부족한 환경에 노출된 차광처리구들에서 암호흡량의 감소, PIABS 및 SFIABS의 증가로 광합성 기구의 활력을 효율적으로 증가시키는 것을 알 수 있다. 한편, 전광은 지상부 비율의 증가, 낮은 T/R율과 가장 높은 순광합성속도를 보여 광합성으로 합성되는 탄수화물이 지상부 뿐만 아니라 지하부의 생장 역시 증가시킨 것을 알 수 있는 결과였다. 따라서 후박나무 용기묘는 전광조건에서 생장 및 생리적 특성이 가장 양호한 경향을 보였다.

Cyanobacterial resting cells, such as akinetes, are important seed cells for cyanobacteria’s early development and bloom. Due to their importance, various methods have been attempted to isolate resting cells present in the sediment. Ludox is a solution mainly used for cell separation in marine sediments, but finding an accurate method for use in freshwater is difficult. This study compared the two most commonly used Ludox methods (direct sediment treatment and sediment distilled water suspension treatment). Furthermore, we proposed a highly efficient method for isolating cyanobacterial resting cells and eDNA amplification from freshwater sediments. Most of the resting cells found in the sediment were akinete to the Nostocale and were similar to those of Dolichospermum, Cylindrospermum, and Aphanizomenon. Twenty times more akinetes were found in the conical tube column using the sediment that had no treatment than in the sample treated by suspending the sediment in distilled water. Akinete separated through Ludox were mainly spread over the upper and lower layers in the column rather than concentrated at a specific depth in the column layer. The mibC, Geo, and 16S rDNA genes were successfully amplified using the sediment directly in the sample. However, the amplification products of all genes were not found in the sample in which the sediment was suspended in distilled water. Therefore, 5 g to 10 g of sediment is used without pretreatment when isolating cyanobacterial resting cells from freshwater sediment. Cell isolation and gene amplification efficiency are high when four times the volume of Ludox is added. The Ludox treatment method presented in this study isolates cyanobacterial resting cells in freshwater sediment, and the same efficiency may not appear in other biotas. Therefore, to apply Ludox to the separation of other biotas, it is necessary to conduct a pre-experiment to determine the sediment pretreatment method and the water layer where the target organism exists.

This study compares the abundance and community structure of zooplankton organisms from pelagic regions, and considers particularly the trophic levels vs. zooplankton abundances and biomass. Zooplankton samples were collected three times from May to November 2022, at 30 temperate lakes and reservoirs, which belong to four different river basins. The total zooplankton abundance, biomass and species index were showed considerable spatial variation. The spatial pattern of rotifer abundance was similar to that of total zooplankton abundance, while there were not showed similar patterns of zooplankton biomass (μg L-1) in lentic ecosystems. The rotifer strongly dominated the zooplankton assemblage in smaller lentic system than that of larger. A total of 130 species of zooplankton were identified (83 rotifers, 34 cladocerans and 13 copepods). The total average of zooplankton abundance and biomass were 213.7±342.3 Ind. L-1 (n=129) and 1382.8±1850.4 μg L-1, respectively. Total and average of zooplankton abundance were usually dominated by the rotifers (>56.9%), while those of zooplankton biomass were dominated by the cladocerans and copepods (>73.6%) in lentic ecosystems. Considering the Trophic State Index (TSI), the factors of zooplankton abundance and biomass were included in between meso- and eutrophic states (27 lakes, 90% of all). The mean abundance and biomass of zooplankton in eutrophic systems were higher than that of meso- and hypertrophic systems. From this result, we suggest that management strategy for the lentic ecosystem water environment has to be focused more on small-sized lakes and reservoirs, in terms of zooplankton assemblages.