In the mid-eastern part of the Yellow Sea, large-scale shelf ridges originated from erosion on sand-mud successions that have been presently eroded by strong tidal currents. A three-layered in situ geoacoustic model is provided down to 50 m for the subbottom sedimentary succession of a 45 m water depth using the Hamilton method. The succession is divisible into two-type units of Type-A and Type-B using high-resolution seismic profiles with a deep-drilled YSDP-104 core of 44.0 m in depth below the seafloor. Type-A unit mainly comprises sandy or gravelly sediments, whereas Type-B unit mostly consists of tidal muddy sediments with some thinner sand beds. P-wave speed values are positively compatible with the mean grain size and sediment type of the core sediments. For actual modeling, the geoacoustic property values of the models were compensated to in situ depth values below the seafloor. The detailed geoacoustic model contributes to simulating sound transmission through the sedimentary successions in erosional shelf ridges of variable geoacoustic properties distributed in shallow-water environments of the mid-eastern Yellow Sea.

한강 3개 보 구간 수변부 11개 지점을 대상으로 2023년 총 2회 채집된 저서성 대형무척추동물은 총 100종 평균 426.0 개체/m2였다. 여주보에서 64종으로 가장 많이 출현하였고, 강천보에서 59종, 이포보에서 54종, 한강보상류 에서 41종, 한강보하류에서 32종이 확인되었다. 전체 평균 개체밀도는 강천보에서 944.1 개체/m2로 가장 많았고, 한강보상류에서 282.7 개체/m2, 여주보에서 251.9 개체/m2, 이포보에서 180.6 개체/m2, 한강보하류에서 172.9 개체 /m2 순으로 확인되었다. 한강 보 구간에서는 플라나리아류, 실지렁이, 깔따구류 등이 우점함. 보구간의 특성상 상대적으로 단순한 하상 및 깊은 수심에 적응성이 높은 실지렁이, 깔따구류의 우점은 일반적인 특성으로 볼 수 있으며 일시적으로 수변부에서 밀집된 플라나리아류의 채집이 이뤄져 우점된 결과를 보인 것으로 보임. 한강 보 구간 수변부 및 중앙부 조사지점별 군집분석을 실시한 결과 한강보 하류는 3개 보에 비해 우점도가 높고 다양도 와 풍부도가 낮았으며 전반적으로 상류부에 위치한 한강보상류 등의 지점에서 군집안정성이 확보되고 있는 것으로 보이며 이러한 점은 상대적으로 다양한 미소서식환경에 기인한 것으로 판단된다.

Abstract Purpose : This study investigated the impact of knowledge and awareness of perception of harmful rays on the use of blue light blocking lenses among university students majoring in optometry. Methods : This study targeted 65 optometry students who responded to an online survey from September 2023 to October 2023. The survey used a survey tool with a total of 15 questions, including knowledge and awareness of perception of harmful rays and demands for guidelines. Statistical analysis was performed using SPSS 19.0. Results : The overall knowledge score about UV rays and blue light was 14.00±3.10 for optometry students and 12.30±3.50 for general university students, showing that the optometry students had higher knowledge (p<0.001). In the case of use of UV-blocking lenses, 70.8% of optometry students were found to be using them, which was higher than 51.5% of general university students. The use of glasses to block blue light was found to be 41.5% of optometry students and 36.9% of general university students. The correlation between perception of the importance of blocking harmful rays and the need for guidelines for the correct selection of blue light blocking lenses was r=0.528 (p<0.001). Conclusion : Optometry students' knowledge and perception of harmful rays were found to be higher than those of general university students, and it appears to have an impact on the use of harmful ray-blocking lenses. Therefore, it is necessary to strengthen education and establish guidelines for the correct selection of harmful ray blocking lenses.

Throughfall (TF)—as a diffusive hydrological water flux—significantly affects ecohydrological and biogeochemical processes within forest ecosystems. Recent investigations have revealed the impact on TF generation processes within unmanaged coniferous plantations of under-canopy structures, particularly those laden with dead branches, as well as upper-canopy structures. However, spatiotemporal variations in TF in such plantations remain unexplored. We investigated these variations in TF in a 33-year-old unmanaged Japanese cypress (Chamaecyparis obtusa Endl.) plantation, laden with dead branches, with a high stand density (SD) of 2,500 stems ha−1. Over a two-year period (May 2017 to May 2019), we conducted weekly TF measurements using 28 manual-type TF collectors. We compared the present TF ratio and canopy water storage capacity (S) with those of previous investigations conducted on Japanese cypress plantations. Moreover, we assessed key indices contributing to spatiotemporal TF variations (canopy cover: CC and distance to the nearest stem: TFd) and potentially influential dead branch indices (number of dead branches: TFdb and vertical spacing length on a stem: TFs) to elucidate TF spatial patterns. The results showed that the TF ratio was notably lower than that in previous studies (n = 13), with SD (r = –0.92, p < 0.001) and S (r = –0.87, p < 0.001) emerging as key influential factors among other stand-structure parameters. Spatial TF patterns exhibited a decreasing trend as the gross rainfall (GR) increased. Temporal stability was not significantly associated with CC (r = 0.120, p = 0.544), TFd (r = 0.068, p = 0.731), TFdb (r = 0.211, p = 0.281), or TFs (r = 0.206, p = 0.292) for any of the TF collectors. These findings underscore the important role of GR in determining the spatial variation of TF. Collectively, our results contribute to an enhanced understanding of TF spatiotemporal heterogeneity in unmanaged Japanese cypress plantations with dead branches.

목적: 본 연구는 COVID-19의 대유행 동안 20~30대 성인을 대상으로 컴퓨터시각증후군 (CVS, computer vision syndrome) 관련 눈의 자각증상과 시력 관련 불편감을 파악하고, 눈 건강을 위해 사용하는 예방법을 알아보고자 하였다. 방법 : 2021년 12월부터 2022년 2월까지 안경 또는 콘택트렌즈 처방과 상담을 위해 일개 안경원에 내원 했던 20~30대 성인 중에서 전신질환 및 안질환, 안과적 수술 경험이 없는 150명을 대상으로 하였다. 연구도구는 대상자의 일반적인 특성(3문항), CVS 자각증상(16문항), 시력 관리(2문항), 눈의 조절기능 이상(2문항), 청색광 차단 안경사용(2문항), 근거리교정(1문항)으로 총 26문항으로 구성된 설문지를 이용하였다. 결과 : 전체 대상자들의 CVS 자각증상은 “눈물이 많이 발생한다”가 109명(72.7%)으로 가장 높은 빈도를 보였 고, 그다음은 “눈이 아프다”가 104명(69.3%)으로 나타났다. CVS 자각증상 중 시력 관련 자각증상은 “사물이 흐 려보인다”가 106명(70.7%)으로 가장 많았다. 시력 관리방법으로는 “시력의 저하를 느껴서”가 105명(70.0%)으로 가장 많았고, 청색광 차단 안경 사용하는 대상자는 150명(84.7%)으로 80% 이상의 대상자들이 기능을 넣어서 사 용하고 있다. 결론 : CVS 자각증상 16문항 중 14문항에서 50% 이상으로 나타났다. 청색광 차단 안경을 사용하지 않는 대상 자는 CVS 자각증상 중 시력과 관련된 “시력이 나빠지는 것 같다”가 69.6%로 가장 높게 나타났다. COVID-19 대 유행 동안 자각적인 불편증상과 시력저하를 호소하는 대상자가 높게 나타나고 있다. 따라서 안경처방 시 생활환 경, 사용시간 및 자각적 증상에 대하여 문진이 필요하다고 생각된다.

At a time when the demand for drones is increasing, a plan to utilize drone images was sought for efficient promotion of cadastral resurvey. To achieve the purpose of this study, the technical and legal status of drone images was reviewed, and through this, the possibility of using it for cadastral resurvey was primarily reviewed. subsequently, an experiment was conducted targeting the project district to examine whether drone images were applied to boundary extraction, which is the primary process of cadastral resurvey. As a result of the experiment, it was found that boundary extraction from images is possible. However, in some cases, it is impossible due to field conditions or image quality. Therefore, it is necessary first to apply cases where boundary extraction is possible to cadastral resurvey and seek solutions for some impossible cases. In particular, the image quality problem may have problems with the current technology, but it will also have problems with the existing drone equipment. So, standard for drone calibration should also be established. Finally, the cadastral resurvey surveying procedure using drones was also presented.

There are many types of foam molding methods. The most commonly used methods are the pressure foaming method, in which foam resin is mixed with a foaming agent at high temperature and high pressure, and the normal pressure foaming method, which foams at high temperature without pressure. The polymer resins used for foaming have different viscosities. For foaming under normal pressure, they need to be designed and analyzed for optimal foaming conditions, to obtain resins with low melt-viscosity or a narrow optimal viscosity range. This study investigated how changes in viscosity, molding temperature, and cross-link foaming conditions affected the characteristics of the molded foam, prepared by blending rubber polymer with biodegradable resin. The morphologies of cross sections and the cell structures of the normal pressure foam were investigated by SEM analysis. Properties were also studied according to cross-link/foaming conditions and torque. Also, the correlation between foaming characteristics was studied by analyzing tensile strength and elongation, which are mechanical properties of foaming composites.

목적: 대학생을 대상으로 자외선을 포함한 청색광과 같은 유해광선에 대한 지식과 인식도를 알아보고자 하였다. 방법 : 2023년 4월부터 5월까지 온라인 설문 조사에 응답한 충남지역 대학생 103명을 대상으로 하였다. 설문 은 대상자의 일반적 특성에 관한 문항, 자외선과 청색광 차단렌즈의 착용실태에 대한 문항, 자외선과 청색광에 대 한 지식도 및 인식도 문항, 그리고 차단렌즈 선택을 위한 가이드라인의 요구도 문항으로 구성된 총 15문항의 설문 도구를 사용하였다. 통계분석은 SPSS 18.0을 사용하였다. 결과 : 자외선 차단을 위해 안경이나 콘택트렌즈를 착용하는 비율은 56.3%로 나타났으나 청색광 차단 안경이 나 콘택트렌즈를 사용하는 경우는 35.9%로 상대적으로 낮은 비율로 나타났다. 자외선과 청색광의 유해성에 관한 지식도는 각각 2.58±0.91, 2.44±0.98로 조사되었으며, 자외선과 청색광으로부터 눈 보호가 중요하다고 생각하 는 항목의 평균 점수는 각각 3.49±0.61, 3.35±0.68점으로 조사되어 자외선과 청색광 차단의 중요성에 대한 인 식도는 높은 것으로 나타났다. 결론 : 대학생들의 자외선과 청색광에 대한 지식도와 인식도는 높은 수준이었으나 청색광 차단렌즈에 올바른 선택법에 대한 지식은 낮은 수준을 나타냈다. 이에 청색광 차단렌즈의 올바른 선택을 위한 교육 강화와 가이드라 인의 구축이 필요할 것으로 판단된다.

Governments around the world are enacting laws mandating explainable traceability when using AI(Artificial Intelligence) to solve real-world problems. HAI(Human-Centric Artificial Intelligence) is an approach that induces human decision-making through Human-AI collaboration. This research presents a case study that implements the Human-AI collaboration to achieve explainable traceability in governmental data analysis. The Human-AI collaboration explored in this study performs AI inferences for generating labels, followed by AI interpretation to make results more explainable and traceable. The study utilized an example dataset from the Ministry of Oceans and Fisheries to reproduce the Human-AI collaboration process used in actual policy-making, in which the Ministry of Science and ICT utilized R&D PIE(R&D Platform for Investment and Evaluation) to build a government investment portfolio.

The inclusion of conductive carbon materials into lithium-ion batteries (LIBs) is essential for constructing an electrical network of electrodes. Considering the demand for cells in electric vehicles (e.g., higher energy density and lower cell cost), the replacement of the currently used carbon black with carbon nanotubes (CNTs) seems inevitable. This review discusses how CNTs can contribute to the development of advanced LIBs for EVs. First, the reason for choosing CNTs as a conducting agent for the cathode is discussed in terms of energy density. Second, the reinforcing effect of CNTs on the anode is described with respect to the choice of silicon as the active material. Third, the development of water-based cathode fabrication as well as dry electrode fabrication with aid of CNTs is discussed. Fourth, three technical hurdles, that is, the price, dispersion issue, and entrapped metal impurities, for widespread use of CNTs in LIBs are discussed.

Acacetin, which is present in damiana (Turnera diffusa ) and black locust (Robinia pseudoacacia ), has several pharmacologic activities such as antioxidant, anti-inflammatory, and anti-proliferative effects on cancer cells. However, the effect of acacetin on head and neck cancers has not been clearly established. This study aimed to examine the effects of acacetin on cell growth and apoptosis induction in FaDu human pharyngeal carcinoma cells. These were investigated by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay, Live/Dead cell assay, 4′,6-diamidino-2-phenylindole dihydrochloride staining, caspase-3 and caspase-7 activation assay, and immunoblotting in FaDu cells. Acacetin induced FaDu cell death in a dose-dependent manner, with an estimated IC50 value of 41.9 µM, without affecting the viability of L-929 mouse fibroblasts as normal cells. Acacetin treatment resulted in nuclear condensation in the FaDu cells. It promoted the proteolytic cleavage of procaspase-3, -7, -8, and -9 with increasing amounts of the cleaved caspase isoforms in FaDu cells. Acacetin-induced apoptosis in FaDu cells was mediated by the expression of Fas and activation of caspase-8, caspase-3, and poly (ADP-ribose) polymerase. Immunoblotting showed downregulation of the anti-apoptotic mitochondrial proteins Bcl-2 and Bcl-xL, but upregulation of the mitochondria-dependent pro-apoptotic proteins Bax and Badin FaDu cells after acacetin treatment. These findings indicate that acacetin inhibits cell proliferation and induces apoptotic cell death in FaDu human pharyngeal carcinoma cells via both the death receptor-mediated extrinsic apoptotic pathway and the mitochondria-mediated intrinsic apoptotic pathway.

The development of drugs from natural plant sources is at growing interest due to the limitations of chemical drugs in terms of side effects and cost-effective factors of natural medicines. Among the various components contained in natural plant materials, flavonoids are of increasing interest because of their extended biological benefits. Flavonoids are classified into various types according to their structure and possess different activities depending on the structure. In this study, the flavonoids contained in Artemisia, native to Korea were examined and reviewed. HPLC chromatograms of three Artemisia species (Artemisia annua L., Artemisia iwayomogi and Artemisia argyi H.) were examined from published sources and their component analysis by MS data were summarized. The various flavonoids of Artemisia were classified into 12 types according to the main structure, and 10 flavonoids based on various activities were examined. The 10 flavonoids were identified as quercetin, kaempferol, rhamnetin, diosmetin, luteolin, methoxyflavone, catechin, apigenin, malvidin and genkwanin with extensive reported studies till date. The ten flavonoids examined have been reported to be effective in preventing and treating various diseases and exhibit activities such as anti-cancer, anti-inflammatory, antioxidant, antiviral, anti-obesity, anti-diabetic and anti-Alzheimer. The collective results from the reported studies suggest that the three types of Korean native Artemisia, contains various flavonoids with beneficial activities and may have therapeutic effects against diseases.

Reliability analysis of the components frequently starts with the data that manufacturer provides. If enough failure data are collected from the field operations, the reliability should be recomputed and updated on the basis of the field failure data. However, when the failure time record for a component contains only a few observations, all statistical methodologies are limited. In this case, where the failure records for multiple number of identical components are available, a valid alternative is combining all the data from each component into one data set with enough sample size and utilizing the useful information in the censored data. The ROK Navy has been operating multiple Patrol Killer Guided missiles (PKGs) for several years. The Korea Multi-Function Control Console (KMFCC) is one of key components in PKG combat system. The maintenance record for the KMFCC contains less than ten failure observations and a censored datum. This paper proposes a Bayesian approach with a Dirichlet mixture model to estimate failure time density for KMFCC. Trends test for each component record indicated that null hypothesis, that failure occurrence is renewal process, is not rejected. Since the KMFCCs have been functioning under different operating environment, the failure time distribution may be a composition of a number of unknown distributions, i.e. a mixture distribution, rather than a single distribution. The Dirichlet mixture model was coded as probabilistic programming in Python using PyMC3. Then Markov Chain Monte Carlo (MCMC) sampling technique employed in PyMC3 probabilistically estimated the parameters’ posterior distribution through the Dirichlet mixture model. The simulation results revealed that the mixture models provide superior fits to the combined data set over single models.