This study was conducted to determine the optimal spring seeding dates for alfalfa yield and feed value. The experiment was conducted annually for three years (2021~2023) at the field in the Department of Animal Resources Development, NIAS, located in Cheonan. The treatments involved six seeding dates ranging from February 24 to April 14, with 10days intervals. Alfalfa was harvested four times a year at the early flowering stage. Dry matter yield showed a tendency to decrease with delayed the seeding date. However, depending on the climatidc condisions in the seeding year, the dry matter yield on March 14 or 24 was comparable to that on February 24. Annual dry matter yield varied, influenced by the daylight conditions each year. The average feed value did not significantly differ within in the same year with delayed seeding dates (p>0.05). Therefore, the most stable period for alfalfa spring seeding in the central area of South Korea is considered to be from February 24 to April 4, with February 24 indentified as the optimal date.

This study was conducted to provide the basic information on environment effects on appearance of ichthyoplankton in the Yeongsan River Estuary in Spring and Summer from 2018 to 2020. Data were obtain from the database of ‘Coastal Ecosystem’ in “National Survey of Marine Ecosystem.” Among the abundance ichthyoplankton species, the Gobiidae spp. dominated, accounting for 85% of the total abundances with the secondary dominant species being the Parablennius yatabei, representing 3% of the abundances. Cluster analysis results revealed a composition differentiated between spring and summer. The Yeongsan River Estuary is known to be significantly influenced by the opening and closing of estuarine gates. In this study, the fluctuation in the number of occurrence groups and abundance among the years and season is attributed to the phenomenon of high water temperature period and the freshwater discharge.

This study deals with the vibration transmissibility of a vibration isolation device, which is composed of frictional damping and nonlinear softening springs, when its base is harmonically excited. The SCAP method, a type of averaging method, is employed to obtain steady-state responses. The vibration characteristics due to excitation of the base are investigated through the analysis of displacement transmissibility in the steady-state response. In this process, displacement transmissibility for design parameters is analyzed, and the stability of the response is also investigated. The vibration isolation effect due to frictional damping is found to be more effective in the case of the softening spring than in the case of the hardening spring. Additionally, the pattern of the jump phenomenon observed during frequency sweeping, both upward and downward, has been identified.

1개월과 3개월 장기 예보를 지원하기 위해 기상청에서 현업운용 중인 GloSea6 기후예측시스템에는 대기 중 대 기화학-에어로졸 물리과정(UKCA)이 연동되어 있지 않다. 본 연구에서는 저해상도의 GloSea6와 여기에 대기화학-에어로 졸 과정을 연동시킨 GloSea6-UKCA를 CentOS 기반 리눅스 클러스터에 설치하여 2000년 봄철에 대한 예비적인 예측 결과를 살펴보았다. 현업 고해상도 GloSea6 모델이 방대한 전산자원을 필요로 한다는 점을 고려할 때, 저해상도 GloSea6와 GloSea6-UKCA 모델은 대기화학-에어로졸 과정의 연동에 따른 효과를 살펴보기에 적합하다. 저해상도 GloSea6와 GloSea6-UKCA는 2000년 3월 1일 00Z부터 75일 간 구동되었으며, 두 모델이 예측한 2000년 4월 지상 기온과 일평균 강수량의 공간 분포를 ERA5 재분석자료와 비교하였다. GloSea6-UKCA가 예측한 기온과 강수 분포는 기존 GloSea6에 비해 ERA5 재분석자료에 보다 더 유사해졌다. 특히 우리나라를 포함한 동아시아 지역에 대해 과대 모의 경 향이 있던 봄철 지상 기온과 일평균 강수량의 예측 결과의 개선이 주목할 만하다. 또한 적분 시간에 따른 예측된 기온 과 강수량의 시계열에서도 GloSea6-UKCA가 GloSea6보다 재분석자료에 더 가까워진 시간 변화 경향을 살펴볼 수 있었 다. 이는 대기화학-에어로졸 과정이 GloSea6에 연동되었을 때 동아시아지역 봄철 예측 성능이 개선될 수 있음을 보여준다.

This paper explores the standards for selecting language materials during the study of the diachronic grammar of Classical Chinese. The accuracy of language materials is crucial for ensuring the scientific validity of research conclusions. Due to previous limitations in research on the language materials of the Spring and Autumn period, such as posteriority and singularity, this paper argues that the increasing availability of excavated documents, especially ancient literary texts, provides a reliable research foundation for describing the grammar of Classical Chinese during this period. Therefore, this paper attempts to answer the following questions: 1) Which language materials should be used for the study of the grammar of Classical Chinese during the Spring and Autumn period? 2) Why should these language materials be selected? 3) What are the standards for selecting language materials during this period? The purpose of this study is to provide a reference for the diachronic study of Classical Chinese grammar.

The seismic retrofits of existing structures have been focused on the control of structural responses which can be achieved by providing displacement capacity through inelastic ductile action at supplemental devices. Due to their hysteretic characteristics, it is expected to sustain damage through repeated inelastic behaviors including residual deformation which might increase repair costs. To solve such drawbacks of existing yielding devices, this study proposes a self-centering disc spring brace that sustains large axial deformation without structural damage while providing stable energy dissipation capacity. The hysteretic behaviors of suggested brace are first investigated based on the quasi-static cyclic test procedure. Experimental results present the effective self-centering behavior and an analytical model is then suggested in order to reasonably capture the flag-shaped hysteretic behavior of the disc spring brace.

This study was aimed to determine the changes in CO2 concentration according to the temperatures of daytime and nighttime in the CO2 supplemental greenhouse, and to compare calculated supplementary CO2 concentration during winter and spring cultivation seasons. CO2 concentrations in experimental greenhouses were analyzed by selecting representative days with different average temperatures due to differences in integrated solar radiation at the growth stage of leaf area index (LAI) 2.0 during the winter season of 2022 and 2023 years. The CO2 concentration was 459, 299, 275, and 239 μmol·mol-1, respectively at 1, 2, 3, and 4 p.m. after the CO2 supplementary time (10:00-13:00) under the higher temperature (HT, > 18°C daytime temp. avg. 31.7, 26.8, 23.8, and 22.4°C, respectively), while it was 500, 368, 366, 364 μmol·mol-1, respectively under the lower temperature (LT, < 18°C daytime temp. avg. 22.0, 18.9, 15.0, and 13.7°C, respectively), indicating the CO2 reduction was significantly higher in the HT than that of LT. During the nighttime, the concentration of CO2 gradually increased from 6 p.m. (346 μmol·mol-1) to 3 a.m. (454 μmol·mol-1) in the HT with a rate of 11 μmol·mol-1 per hour (240 tomatoes, leaf area 330m2), while the increase was very lesser under the LT. During the spring season, the CO2 concentration measured just before the start of CO2 fertilization (7:30 a.m.) in the CO2 enrichment greenhouse was 3-4 times higher in the HT (>15°C nighttime temperature avg.) than that of LT (< 15°C nighttime temperature avg.), and the calculated amount of CO2 fertilization on the day was also lower in HT. All the integrated results indicate that CO2 concentrations during the nighttime varies depending on the temperature, and the increased CO2 is a major source of CO2 for photosynthesis after sunrise, and it is necessary to develop a model formula for CO2 supplement considering the nighttime CO2 concentration.

우리나라에 서식하는 주요 말벌류는 벌목(Hymenoptera)의 말벌아과(Vespinae)에 속하는 종들로 10종의 말벌속 (Vespa) 중 8종[장수말벌(V. mandarinia), 꼬마장수말벌(V. ducalis), 등검은말벌(V. velutina nigrithorax), 좀말 벌(V. analis), 말벌(V. crabro flavofasciata), 검정말벌(V. dybowskii), 털보말벌(V. simillima simillima), 황말벌 (V. simillima xanthoptera)]이 주를 이루고 있다. 특히 2003년 부산에서 처음 발견되었던 등검은말벌이 급속도로 확산되어 우리나라 양봉산업에 치명적인 피해를 주고 있는 현실이다. 이에 본 연구는 충남 주요 양봉지역인 공주, 청양, 논산에서 말벌 유인액을 주입한 포획기를 이용하여 4월부터 6월까지 봄철 출현하는 여왕말벌의 포획된 말벌 류 개체들을 조사하여 분포도와 특성을 알아보았다. 말벌 포획 개체수 조사결과, 등검은말벌의 분포율이 공주 76.3%, 청양 74.1%, 논산 58.0%로 가장 큰 비율을 보였으며, 꼬마장수말벌이 다음으로 공주와 청양지역은 밤나무 숲으로 12.4~16.0%를 보였던 반면, 소나무 숲을 이룬 논산에서는 31.8%로 최대 2.5배 정도 높은 분포 비율을 나타냈 다. 그리고 장수말벌은 5.2~8.6%의 분포율을 보였으며, 다른 지역보다 해발이 높았던 청양지역에서 장수말벌이 많게 조사되었다. 봄철 3개 지역에서 포획된 여왕말벌류의 총개체수(266마리)에 대한 평균 분포 비율은 등검은말 벌 69.5%, 꼬마장수말벌 19.9%, 장수말벌 6.8%, 말벌 2.6%, 그리고 좀말벌 1.1% 순으로 조사되었다.

This study analyzed the chemical characteristics and physiological activity of five kinds of fresh vegetables produced in trees in early spring and tried to use them as basic data for wild vegetable producers and processed food manufacturers using wild vegetables. The crude protein, minerals, ascorbic acid, folate, total phenol, total flavonoid, DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity and ACE (angiotensin converting enzyme) inhibitory activity were determined. Five spring wild vegetables contain high protein and phosphorus, indicating that they are useful food ingredients as sources of protein and phosphorus. Vitamin C content was high in R. venicifera and C. sinensis shoots, and in particular, R. venicifera and A. cortex shoots have high folic acid (folate) contents of 1,903.91 ug% and 1,525.35 ug%, respectively, which is considered a good food for folic acid intake in spring. The total phenol content was between 0.52% and 1.27%, and it was the highest in C. sinensis of 1.27%, followed by the order of R. venicifera, A.cortex, K.pictus, and A. elata, which tended to be consistent with the total flavonoid content. As for DPPH radical scavenging ability, C. sinensis (55.93%) showed the highest activity, and ACE inhibitory activity showed the highest activity in A. cortex (88.04%).

Phytoplankton communities, with emphasis on picoplankton and nanoplankton, were investigated in Gamak Bay, South Korea, where freshwater input and coastal water intrusion shape ecosystem functions. Shellfish farms and fish farms are located in the inner bay and outer bay, respectively, and tides translocate uneaten food and urine production from aquaculture farms toward the inner bay. Water masses were distinctly different based on a significantly different density between the surface and bottom layer and among three water masses, including the inner bay, outer bay, and Yeosu Harbor. Phytoplankton communities were quantified using flow cytometry and size-fractionated chlorophyll-a (chl-a) was measured. Salinity was a principal variable separating phytoplankton communities between the surface and bottom layer, whereas Si(OH)4 controlled the communities in the inner bay, and NH4 + and PO4 3- governed the outer bay communities. While phycocyanin-containing (PC) cyanobacteria dominated in the outer bay, phycoerythrin-containing (PE) cyanobacteria dominance occurred with cryptophyte dominance, indicating that nutrients affected the distribution of pico- and nanoplankton and that cryptophytes potentially relied on a mixotrophic mode by feeding on PE cyanobacteria. Interestingly, picoeukaryotes and eukaryotes larger than 10 μm were mostly responsible for the ecological niche in the western region of the bay. Given that chl-a levels have historically declined, our study highlights the potential importance of increased small phytoplankton in Gamak Bay. Particularly, we urge an examination of the ecological role of small phytoplankton in the food supply of cultivated marine organisms.

Ammonia (NH3) is a basic gas in the atmosphere and is known to play an important role in producing adverse health and environmental effects. Atmospheric NH3 causes stunted livestock growth, decreased visibility, and induces lung diseases when high concentrations occur. In addition, atmospheric NH3 reacts with acidic species (sulfuric acid, nitric acid, etc.) and produces secondary inorganic aerosol. In this study, the NH3 concentration and ventilation of Rooms 1 to 3 inside a sow facility were measured during the period from March 25 to May 31, 2021. It was difficult to conduct long-term field experiments at housing where pigs are raised. However, in order to improve the accuracy and reliability of the data, repeated experiments were conducted in three pig rooms in the same environment. The average concentration of NH3 in Rooms 1 to 3 was measured to be 7.6 ± 2.7 ppm, 8.2 ± 2.8 ppm, and 8.2 ± 2.7 ppm, respectively. The average internal temperatures were 21.0 oC, 21.2 °C, and 21.8 °C, and the internal humidity was 49.3%, 49.2%, and 49.2%, respectively. The ventilation per pig in Rooms 1 to 3 was measured as 60.4m3/hour∙pig, 62.5m3/hour∙pig, and 64.9m3/hour∙pig, respectively. At this time, NH3 emissions from Rooms 1 to 3 were found to be 6.9 ± 0.8 g/day∙pig, 7.9 ± 1.5 g/day∙pig, and 8.2 ± 1.3 g/day∙pig, respectively. As a result of the correlation analysis, the NH3 concentration was analyzed as producing a negative correlation between the ventilation (r=-0.73) and the internal temperature (r=-0.60) increase. Finally, as a result of calculating the national NH3 emission factor, the NH3 emission of one sow room in spring was 7.7 ± 1.4 g/day∙pig, and the NH3 emission of one year was 2.8 kg/ year∙pig.

This study was conducted to examine the dry matter yield and weed control of alfalfa according to postemergence herbicides treatment during spring seeding alfalfa. The seeding time of alfalfa was April 21, 2021, the seeding amount was 20 kg/ha, and the seeding method was by 20 cm wide. The alfalfa harvest was carried out at the early bloom stage (10% of flowering), and the harvest date was June 29, 2021. The test treatments were non herbicide (NH), hand weeding (HW), herbicide 1 (Trifluralin, H1), herbicide 2 (S-metolachlor, H2), herbicide 3 (Alachlor, H3), and herbicide 4 (Pendimethalin, H4). Alfalfa plant height was significantly highest in H2 (62.1±1.4 cm) followed by H3 (61.7±1.6 cm), HW (58.5±1.0 cm), H1 (57.2±1.3 cm), H4 (56.1±1.3 cm), and NH (54.1±1.2 cm) (p<0.05). Based on HW, H2 and H3 were high and H1 and H4 were short, but NH was significantly shorter than HW and H1~H4 (p<0.05). The dry matter yield of alfalfa in NH, HW, H1, H2, H3, and H4 were 717.2±94.2, 2,613.8±254.1, 1,667.8±94.1, 2,498.3±120.2, 2,435.0±118.3, and 1,793.7±354.3 kg/ha. HW is the highest among them (p<0.05). The feed composition of alfalfa was 22~24% of the dry matter yield, and the CP content were significantly higher in NH (23.6 %) (p<0.05). The NH had higher (p<0.05) NDF and ADF, but RFV was lower (p<0.05). The weed plant height was NH 98.0±3.3cm, HW 73.3±1.7 cm, H1 91.9±1.5 cm, H2 53.3±5.8 cm, H3 81.4±3.5 cm and H4 96.6±2.2 cm, and H2 was significantly smallest in the group (p<0.05). The weed dry matter yield was NH 4,770.4±232.5 kg/ha, HW 316.3±91.9 kg/ha, H1 2,353.4±173.7 kg/ha, H2 114.5±10.2 kg/ha, H3 752.7±440.6 kg/ha and H4 2,220.6±775.6 kg/ha. The weed control value was HW 94.1%, H1 53.5%, H2 98.2%, H3 84.9%, H4 48.7%, the weed value of H2 is similar to weed control value of HW. Considering the above results, postemergence herbicide treatment controlled weeds by more than 50% compared with no treatment, and among herbicides, H2 (S-metolachlor) was found to be on a similar level to hand weeding.

본 연구는 중국 산둥성 쯔보시 인민공원과 치성호 공원 이용자 설문조사 결과를 바탕으로 식재경관 조성지표 간의 상관성 및 유형화 특성을 분석할 목적으로 시도되었다. 연구결과를 요약하면 다음과 같다. 대부분 식재경관 조성지표 간 상관성이 있었으며, 사계절 경관과 흥미로운 식재와의 상관성이 가장 높았고 식물의 안전성과 식물 공간구축의 상관성이 그 다음이었다. 요인분석 결과, 미적 요인, 재료적 요인, 이용적 요인, 관리적 요인으로 유형화되었으며, 식물 층위의 미·꽃모양의 다양성·꽃색의 다양성·친근한 식물·교목과 관목 비율·식물의 상징성이 미적 요인에서 뚜렷한 영향을 미쳤다. 재료적 요인은 식물의 공간구축과 사계절 경관, 이용적 요인은 나무의 그늘과 식물종다양성, 관리적 요인은 식물 보호 관리가 비교적 영향이 큰 것으로 나타났다.