The utilization of pig slurry (PS) as an organic fertilizer plays a pivotal role in nutrient recycling within agricultural systems. However, this practice concomitantly leads nitrogen (N) losses through ammonia (NH₃) volatilization and nitrous oxide (N₂O) emissions. The objective of this study was to investigate the effect of wood biochar on mitigating NH3 and N2O emissions and enhancing N retention from PS-applied soil, and plant biomass production during the vegetative growth of rapeseed (Brassica napus L.). The experiment consisted of three treatments: 1) water (non-PS), 2) PS, and 3) PS combined with wood biochar (PS+WB). The PS+WB treatment resulted in the maintenance of elevated soil water content during the experimental period. The PS+WB treatment significantly enhanced soil nitrogen retention compared to PS alone, maintaining higher total N and NH₄⁺-N levels while reducing NO₃⁻ -N accumulation. Wood biochar application also leds to substantial reductions in NH₃ and N₂O emissions, mitigating environmental N losses. The PS+WB treatment resulted in an improvement of shoot biomass, crude protein content, and total digestible nutrients, indicating enhanced forage quality. The increased soil moisture content in PS+WB further contributed to plant growth benefits. These findings demonstrate that wood biochar is an effective amendment for improving nitrogen retention, reducing gaseous N emissions, and enhancing crop productivity in PS-amended soils.

This study aimed to evaluate the effectiveness of a zeolite and sulfuric acid mixture (ZS) as an air filter to mitigate the emissions of ammonia (NH3), nitrous oxide (N2O), and methane (CH4) during the composting of cattle manure. Compared to the control group (blank), ZS reduced NH3 emissions by 91.4%, N2O emissions by 33.6%, and CH4 emissions by 20.0% over the 100-day composting period. Additionally, sulfuric acid in the ZS reacted with NH3, storing it as ammonium sulfate [(NH4)2SO4], which can serve as a source of nutrients such as nitrogen (N) and sulfur (S). To evaluate the fertilizing efficiency of [(NH4)2SO4] in ZS for maize growth, we applied four treatments: control (non-N fertilizer), collected ZS (cZS), cattle manure (organic fertilizer, OF), and urea (chemical fertilizer, CF). Compared to the control, cZS increased total dry weight (DW) by 48%, total digestible nutrients (TDN) by 7.3%, and crude protein (CP) by 77.8%. No significant differences were found among the applications of cZS, OF, and CF. These results suggest that the zeolite mixed with sulfuric acid effectively reduces hazardous gas emissions such as NH3, CH4, and N2O during cattle manure composting. Furthermore, the collected zeolite can potentially be reused as fertilizer, suggesting a positive opportunity for resource recycling to mitigate environmental pollution.

This study aimed to evaluate the efficiency of combining acidification with adsorbents (zeolite and biochar) to mitigate the environmental impacts of pig slurry, focusing on ammonia (NH3) emission and nitrate (NO3 -) leaching. The four treatments were applied: 1) pig slurry (PS) alone as a control, 2) acidified PS (AP), 3) acidified pig slurry with zeolite (APZ), and 4) acidified pig slurry with biochar (APB). The AP mitigates NH3 emission and NO3 - leaching compared to PS alone. Acidification reduced the cumulative NH3 emission and its emission factor by 35.9% and 12.5%, respectively. The APZ and APB increased NH4 +-N concentration, with the highest level in APB, compared to AP. The NH4 + adsorption capacity of APB (0.90 mg g-1) was higher than that of APZ (0.63 mg g-1). The APB and APZ treatments induced less NH3 emission compared to AP. The cumulative NH3 emission was reduced by 12.2% and 27.6% in APZ and APB, respectively, compared to AP treatment. NO3 - leaching began to appear on days 12 and 13, and its peak reached on days 16 and 17, which were later than AP. The cumulative NO3 - leaching decreased by 17.7% and 25.0% in APZ and APB, respectively, compared to AP treatment. These results suggest that combining biochar or zeolite with acidified pig slurry is an effective method to mitigate NH3 emission and NO3 - leaching, with biochar being particularly effective.

󰡔유몽천자(牖蒙千字)󰡕는 한국개신교선교사 게일(James Scarth Gale(한국명 : 奇一), 1863-1937)과 그의 조사(pundit) 이창직(李昌稙, 1866-1936)이 함께 편찬한 경신 학교와 정신여학교의 교과서이다. 이 책은 총 4권으로 구성된 교재다. 여기에 실린 내용 은 자연과학, 사회과학, 서양의 역사, 서양의 인물, 서양의 문학, 우리의 한문고전에 관한 것 등으로 이루어져 있다. 더불어 개화기에 우리의 어문 생활에 필요하다고 생각한 한자 와 관련 정보, 한자어, 국한문, 한문에 관한 지식을 정식 학교 교육을 받는 학생들에게 알 려 주기 위하여 편찬한 것이다. 본고에서는 이러한 󰡔유몽천자󰡕 전집의 체계와 구성, 전 집을 구성하는 3가지 문체 유형, 그리고 전집에 새겨져 있는 개신교선교사의 문체실험의 역사를 고찰했다.

The metal bush assembling process is a process of inserting and compressing a metal bush that serves to reduce the occurrence of noise and stable compression in the rotating section. In the metal bush assembly process, the head diameter defect and placement defect of the metal bush occur due to metal bush omission, non-pressing, and poor press-fitting. Among these causes of defects, it is intended to prevent defects due to omission of the metal bush by using signals from sensors attached to the facility. In particular, a metal bush omission is predicted through various data mining techniques using left load cell value, right load cell value, current, and voltage as independent variables. In the case of metal bush omission defect, it is difficult to get defect data, resulting in data imbalance. Data imbalance refers to a case where there is a large difference in the number of data belonging to each class, which can be a problem when performing classification prediction. In order to solve the problem caused by data imbalance, oversampling and composite sampling techniques were applied in this study. In addition, simulated annealing was applied for optimization of parameters related to sampling and hyper-parameters of data mining techniques used for bush omission prediction. In this study, the metal bush omission was predicted using the actual data of M manufacturing company, and the classification performance was examined. All applied techniques showed excellent results, and in particular, the proposed methods, the method of mixing Random Forest and SA, and the method of mixing MLP and SA, showed better results.

Ambient Air Vaporizer (AAV) is an essential facility in the process of generating natural gas that uses air in the atmosphere as a medium for heat exchange to vaporize liquid natural gas into gas-state gas. AAV is more economical and eco-friendly in that it uses less energy compared to the previously used Submerged vaporizer (SMV) and Open-rack vaporizer (ORV). However, AAV is not often applied to actual processes because it is heavily affected by external environments such as atmospheric temperature and humidity. With insufficient operational experience and facility operations that rely on the intuition of the operator, the actual operation of AAV is very inefficient. To address these challenges, this paper proposes an artificial intelligence-based model that can intelligent AAV operations based on operational big data. The proposed artificial intelligence model is used deep neural networks, and the superiority of the artificial intelligence model is verified through multiple regression analysis and comparison. In this paper, the proposed model simulates based on data collected from real-world processes and compared to existing data, showing a 48.8% decrease in power usage compared to previous data. The techniques proposed in this paper can be used to improve the energy efficiency of the current natural gas generation process, and can be applied to other processes in the future.

본 보고는 2020년 산림 지역에서 대발생하여 큰 피해를 준 매미나방과 대벌레에 의한 피해면적과 피해수종에 대해 기술하였다. 매미나방에 의한 식엽 피해는 강원(1,638 ha), 경기(1,134 ha), 충북(726 ha), 서울(476 ha) 등 중부지방을 중심으로 심각하였다. 대벌레는 서울시 은평구와 고양시 덕양구 사이에 위치한 봉산(약 19 ha)에서 대발생하였다.

2017년 발생한 포항 지진으로 인하여 천장재, 외장재, 커튼월 등 비구조재의 파괴에 의한 피해가 다수 보고되었으며 비구조재의 내진설계가 중요해지고 있다. 본 연구에서는 임팩트해머 테스트를 통해 행어볼트 길이에 따른 천장재의 고유진동수와 감쇠비를 식별하였다. 또한 천장재가 벽 또는 다른 구조체에 충돌하는 경우 발생하는 충격효과를 정확히 고려하기 위해 충돌실험을 수행하였다. 식별된 천장재의 동특성과 충격지속시간을 바탕으로 실제로 천장재가 지진하중으로 인하여 주변 구조물과 충돌이 발생하는 경우에 대한 천장재 응답특성을 수치해석을 통하여 분석하였다. 수치해석 시뮬레이션 결과, 충격하중은 이격거리에 따라 선형적으로 증가하는 경향을 보였으며, 달대길이와는 무관한 것으로 나타났다.

본 논문에서는 실제 공연장을 예제 건물로 하여 공연장에 발생한 진동을 측정한 결과를 바탕으로 공연장 구조물의 안전성에 대해 해석적으로 평가하였다. 수치해석 프로그램은 MIDAS GEN을 사용하였으며, 바닥판은 합성효과를 고려하여 모델링 하였다. 해석결과 진동계측실험을 통해 구한 바닥판 고유진동수와 유사한 결과를 보였다. 또한 군중의 율동에 의한 동적하중을 시간이력해석으로 해석하여 진동계측 실험과 유사한 수준의 바닥판 가속도 응답을 확인하였다. 이 모델을 사용하여 예제 공연장의 최대관람인원인 400명의 집단율동 시 발생하는 상황에 대하여 분석하였다. 그 결과 기둥과 보의 가해지는 외력은 설계 내력을 하회하여 안전성에 문제없음을 확인하였다. 또한 공연 시 발생하는 수평방향 진동수준은 지진하중의 2% 수준으로 수직수평 모두 안전성에 문제가 없는 것을 확인하였다.

The present study was carried out to deduce optimum harvesting time based on fruit traits that were examined with fruits hanging the higher part (HP, higher than or equal to 2m height from the ground) and lower part (LP, lower than or equal to 1.5m height from the ground) on ‘Niitaka’ tree. The fruits of HP compared to of LP tended to be heavy and showed significantly higher soluble solid contents (SSC), hardness and gravity at each of the harvest time. On the basis f the discrepancies of the fruit traits between HP and LP, harvest time for the fruits of LP are acquired to be delayed for raising fruit weight and SSC. Due to the substantial probability of flesh pithiness based on the dramatic decrease of fruit gravity, it is necessary that the fruits of LP distributed just after harvesting or stored for short-term period.

국내 출원 예정인 알스트로메리아 유망 교잡 계통 C269의 기내번식체계 조건 구명을 통해 국산묘의 안정적인 보급에 기 여하고자 본 연구를 수행하였다. 생장점을 MS배지에 치상하 여 초대배양 후, 준비된 근경 생장점은 근경 증식을 위해 6-Benzylaminopurin(BAP)와 Kinetin(KIN)처리를 하였다. KIN 처리구의 경우, 신초 발생량이 많고 조밀하게 생장 했다. 이는 근경 증식을 위한 근경 분리가 힘들어 근경 증식에는 적합하 지 않았다. BAP 처리구의 경우 0.2mg·L-1이하의 농도 배지 에서 키운 근경을 분리하여 증식 시키는 것이 적합할 것으로 생각되었다. 뿌리 발근 배지는 1-Naphthaleneacetic acid(NAA) 0.25mg·L-1첨가 배지에서 가장 많은 뿌리가 발생되었다. 하 지만, NAA 호르몬 처리에 의한 비정상적인 뿌리 비대가 발생 되었다. 반대로 무처리구에서는 정상적인 뿌리, 세근 및 뿌리 털 발생이 더 좋았다. 순화 과정 중에는 호르몬 처리구 보다 무처리구가 많은 생존률을 보였을 뿐만 아니라 신초 발생 및 지상부 생육도 무처리구에서 왕성하였다. 결론적으로 알스트 로메리아 교잡 계통 C269는 BAP 0.2mg·L-1처리에서 근경을 증식한 후 MS 배지로 옮겨 치상 후 발근을 유도하여 순화를 시키는 것이 효과적인 증식체계로 판단되었다.

The purpose of this study is to accurately estimate the wind-induced responses of a tall building structure for using the estimated responses in the process of calculating the optimal force of an active control device. Kalman filter was used for the estimation process and a 3-storied model structure on a shaking table was tested for the verification of the estimation accuracy. The system matrices of the model were constructed based on the mode parameters obtained by the system identification. The estimated displacement matched up well with the measured one. Finally, the wind-induced responses of a real 39-storied building structure excited by the typhoon MUIFA were estimated.