As Jeju people hopes to make an effort to find its place for 4.3 Grand Tragedy in the Sun, they will contribute to world peace beyond the Jeju 4.3 Tragedy. It will be a starting point that Jeju people propose to U.S. Congress “the Korea Jeju Human Rights and Peace Island Act 2021". It was meaningful that Jeju National University students suggested their idea about enactment of Jeju 4.3 Reconciliation Act to U.S. Congress at the meeting of both office of Congressman Mark Takano and Congresswoman Judy Chu on May 1, 2019. It may be going forward for us to do Jeju Massacre Consultation based on Jeju 4.3 Reparative Justice with cooperation of both U.N. lawyer and international law professors. It would be a historic achievement in the Human Rights and Democracy in 21st century similar to the Civil Liberty Act 1988 to Japanese Internment cases and the Hong Kong Human Rights and Democracy Act 2019 to Hong Kong democratization.

본 연구는 합천호에서 2002~2017년까지 16년간의 장기간 동안 수질변수를 이용하여 부영양화 특성, 경험적 모델분석 및 몬순강도에 따른 수질변이 특성을 분석하였다. 장기간의 연별 수질 분석에서 합천호는 중영양 ~부영양 상태로 분석되었고, 계절별 수질분석에서 부영양화 현상은 하절기 이후 심화되는 것으로 나타났다. 장기간의 수질변이 특성은 유역의 점오염원 및 비점 오염원이 크게 변하지 않는 상황 하에서 매년 강우 사상 (집중 강우 vs. 약한 강우) 및 계절적인 강우강도에 의해 조절되는 것으로 분석되었다. 총인(TP), 총질소(TN), 생물학적 산소요구량(BOD) 및 이온 농도변화는 건기해(Dry year)와 홍수해 (Wet year)의 비교분석에서 뚜렷한 차이를 보여 영양염류, 유기물 농도 및 이온농도 변동에 가장 중요한 역할을 하는 것으로 분석되었다. 특히, 수질 변수 중 매년 영양염 지표(TP, TN), 유기물 지표(BOD, COD), 총 부유물질 농도 및 1차생산력의 지표 (Chl-a)는 강수량과 정상관관계를 보였다. 녹조의 지표인 Chl-a 농도는 총인, 총질소, 및 BOD와 높은 상관관계를 보여, 타 호수처럼 영양염의 과도한 증가시기에 Chl-a농도가 낮아지는 특성과는 차이를 보였다. Log-전환된 총질소, 총인 및 Chl-a에 대한 경험적 모델(Empirical model) 분석에 따르면, Chl-a 농도는 인(phosphorus) 농도에 의해 1차적으로 조절되며, 질소(N)농도는 유의한 영향을 주지 않는 것으로 나타났다. 이는 Log10TN, Log10TP, Log10CHL의 상류, 중류, 하류구간에 대한 공간적 회귀분석에서 총인과 Chl-a는 p <0.005의 유의적인 상관관계를 나타내었으나 총질소와 Chl-a는 p > 0.005의 결과를 보여, 녹조번성에 대해 인(P)이 핵심역할을 하는 것으로 분석 되었다. 또한, 총질소와 총인 모두 Chl-a와 댐에 가까운 하류구간(Lacustrine zone)에 비해 상류구간(Riverine zone)에서 더 유의적인 결과를 보여, 상류역에서 무기성 부유물의 농도의 영향에 의한 광제한 효과(Light limitation)가 거의 나타나지 않는 것으로 분석되었다.

An artificial neural network (ANN) model is developed for the analysis and simulation of correlation between flake powder metallurgy parameters and properties of AA2024-SiC nanocomposites. The input parameters of the model are AA 2024 matrix size, ball milling time, and weight percentage of SiC nanoparticles and the output parameters are density and hardness. The model can predict the density and hardness of the unseen test data with a correlation of 0.986 beyond the experimental data. A user interface is designed to predict properties at new instances. We have used the model to simulate the individual as well as the combined influence of parameters on the properties. Moreover, we have analyzed the calculated results from the powder metallurgical point of view. The developed model can be used as a guide for further composite development.

We present the analysis of KMT-2016-BLG-0212, a low flux-variation (Iflux−var ∼ 20 mag) microlensing event, which is in a high-cadence (Γ = 4hr −1) field of the three-telescope Korea Microlensing Telescope Network (KMTNet) survey. The event shows a short anomaly that is incompletely covered due to the brief visibility intervals that characterize the early microlensing season when the anomaly occurred. We show that the data are consistent with two classes of solutions, characterized respectively by low-mass brown-dwarf (q = 0.037) and sub-Neptune (q < 10−4) companions. Future high-resolution imaging should easily distinguish between these solutions.

Foreign Reception Hall in Gyeongungung Palace was constructed during 1899-1902 according to Yesigjangjeong (禮式章程), Korean Empire's modern diplomatic protocol. This bulilding is a case worthy of notice, because its construction process was written in Jubon(奏本), Korean Empire's official document. Yesigjangjeong(禮式章程) regulates the process of diplomat's audience with Emperor Gojong. The process suggested that Foreign Reception Hall was designed as the place of the end as well as the beginning for audience. According to the process, diplomat came through main gate, Daehanmun and outer gate of main hall(Junghwajeon Hall, Audience Hall), then arrived at the stair to Foreign Reception Hall. After waiting time in the hall, he was going to be granted an audience with Emperor. And he exited through Foreign Reception Hall as the reverse way. This hall was constructed as western-style. Subcontracted carpenters and wood sculptors and laborers from China represents that chinese workers were prevailed in the government construction at that time. And modern building materials, such as glass, colored brick, sanitary wares and lightings were applied, which showed the new landscape in the middle of Gyeongungung Palace. Above all, official documents related with this hall reveals Korean Empire supervised this construction for diplomatic protocol. That is the identity of western-style buildings in Gyeongungung Palace.

The subfamily Nitidulinae in Korea is reviewed with a pictorial key to species. In total, 30 species of 18 genera are recognized including three newly recorded genera, each with one species respectively: Nitidula rufipes (Linnaeus, 1767), Stelidota multiguttata Reitter, 1877 and Hebasculinus japonus (Reitter, 1877). Pictorial key to tribes, genera and species with illustrations of habitus are provided.