Mo-ODS alloys have excellent mechanical properties, including an improved recrystallization temperature, greater strength due to dispersed oxides, and the ability to suppress grain growth at high temperatures. In ODS alloys, the dispersed Y2O3 and added Ti form Y-Ti-O complex oxides, producing finer particles than those in the initial Y2O3. The complex oxides increase high-temperature stability and improve the mechanical properties of the alloy. In particular, the use of TiH2 powder, which is more brittle than conventional Ti, can enable the distribution of finer oxides than is possible with conventional Ti powder during milling. Moreover, dehydrogenation leads to a more refined powder size in the reduction process. This study investigated the refinement of Yi2Ti2O7 in a nano Mo-ODS alloy using TiH2. The alloy compositions were determined to be Mo-0.5Ti-0.5Yi2O3 and Mo-1.0Ti-0.5Yi2Oi2. The nano Mo-ODS alloys were fabricated using Ti and TiH2 to explore the effects of adding different forms of Ti. The sintered specimens were analyzed through X-ray diffraction for phase analysis, and the microstructure of the alloys was analyzed using scanning electron microscopy and transmission electron microscopy. Vickers hardness tests were conducted to determine the effect of the form of Ti added on the mechanical properties, and it was found that using TiHi2 effectively improved the mechanical properties.

In this study, a core-shell powder and sintered specimens using a mechanically alloyed (MAed) Ti-Mo powder fabricated through high-energy ball-milling are prepared. Analysis of sintering, microstructure, and mechanical properties confirms the applicability of the powder as a sputtering target material. To optimize the MAed Ti-Mo powder milling process, phase and elemental analyses of the powders are performed according to milling time. The results reveal that 20 h of milling time is the most suitable for the manufacturing process. Subsequently, the MAed Ti-Mo powder and MoO3 powder are milled using a 3-D mixer and heat-treated for hydrogen reduction to manufacture the core-shell powder. The reduced core-shell powder is transformed to sintered specimens through molding and sintering at 1300 and 1400oC. The sintering properties are analyzed through X-ray diffraction and scanning electron microscopy for phase and porosity analyses. Moreover, the microstructure of the powder is investigated through optical microscopy and electron probe microstructure analysis. The Ti-Mo core-shell sintered specimen is found to possess high density, uniform microstructure, and excellent hardness properties. These results indicate that the Ti-Mo core-shell sintered specimen has excellent sintering properties and is suitable as a sputtering target material.

This study examines and proposes standardization approaches to address the heterogeneous issues of metadata in drone imagery within the agricultural sector. Image metadata comes in various formats depending on different camera manufacturers, with most utilizing EXIF and XMP. The metadata of cameras used in fixed-wing and rotary-wing platforms, along with the metadata requirements in image alignment software, were analyzed for sensors like DJI XT2, MicaSense RedEdge-M, and Sentera Double4K. In the agricultural domain, multispectral imagery is crucial for vegetation analysis, making the provision of such imagery essential. Based on Pix4D SW, a comparative analysis of metadata attributes was performed, and necessary elements were compiled and presented as a proposed standardization (draft) in the form of tag information.

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.

This study investigates the melting point and brazing properties of the aluminum (Al)-copper (Cu)-silicon (Si)-tin (Sn) alloy fabricated for low-temperature brazing based on the alloy design. Specifically, the Al-20Cu-10Si-Sn alloy is examined and confirmed to possess a melting point of approximately 520oC. Analysis of the melting point of the alloy based on composition reveals that the melting temperature tends to decrease with increasing Cu and Si content, along with a corresponding decrease as the Sn content rises. This study verifies that the Al-20Cu-10Si-5Sn alloy exhibits high liquidity and favorable mechanical properties for brazing through the joint gap filling test and Vickers hardness measurements. Additionally, a powder fabricated using the Al-20Cu-10Si-5Sn alloy demonstrates a melting point of around 515oC following melting point analysis. Consequently, it is deemed highly suitable for use as a low-temperature Al brazing material.

In this study, Tröger’s Base (TB) chemistry is exploited to introduce tunable microporosity in commercially available polyimide membranes. Considering that TB is a rigid, V-shaped and bridged alicyclic amine, there have been notable reports on accessing feasibility in TB for gas separation membrane applications. However, this presentation shows a different but much viable preparation approach in comparison to the already reported ones. This approach only requires commercially available monomers with two preparation steps, thus it can accommodate scalable and practical productions. Five different kinds of homopolymers and six copolymers were explored to demonstrate structure-property-performance relationships and to evaluate practical applicability towards industrial level.

본 연구에서는 약용식물 추출물을 함유한 숙취해소 음료가 항산화 및 알코올 분해에 미치는 영향을 조사하기 위하여, 약용식물 추출물의 총 페놀성화합물 함량, 총 플라보노이드 함량 및 DPPH radical 소거활성 및 ALDH(aldehyde dehydrogenase) 활성을 측정하였고, 약용식물 추출물을 함유한 숙취해소 음료의 복용이 음주 후 호흡 중 알코올 농도에 미치는 영향을 조사하였다. 항산화활성은 빼빼목 추출물 에서 높은 수치(total phenolic compound 97.5.6mg/g, total flavonoid 306.5mg/g, DPPH radical 소거능 80.1%)를 나타냈으며 Acetaldehyde(ALDH)에 대한 활성은 헛개 및 울금 추출물에서 306% 및 292%로 가장 높은 활성을 나타내어, 헛개 및 울금 추출물이 ALDH 제거에 효과적인 것으로 나타났다. 헛개 및 울금 추출물이 함유된 숙취해소 음료를 이용하여, 임상실험을 실시한 결과, 시간경과에 따라 대조군에 비해 숙취해소음료 섭취군에서 알코올 농도가 감소되는 경향을 나타냈으며 흡연자에 비해 비 흡연자가, 남성에 비해 여성에게 숙취해소 음료의 섭취가 더 효과적인 것으로 확인되었다.

The oocyte undergoes various events during In vitro maturation (IVM) and subsequence development. One of the events is production of reactive oxygen species (ROS) that is a normal process of cell metabolism. But imbalances between ROS production and antioxidant systems induce oxidative stress that negatively affect to mammalian reproductive process. In vitro environments, In vitro matured oocytes have many problems, such as excessive production of ROS and imperfect cytoplasmic maturation. Therefore, In vitro matured oocytes still have lower maturation rates and developmental competence than in vivo matured oocytes. In order to improve the IVM and In vitro culture (IVC) system, antioxidants, vitamins were added to the IVM, IVC medium. Antioxidant supplementation was effective in controlling the production of ROS and it continues to be explored as a potential strategy to overcome mammalian reproductive disorders. Based on these studies, we expect that the use of antioxidants in porcine oocytes could improved maturation and development rates.

This study was carried out to investigate the characterization of iron oxide nanotubes (INTs) by anodization method and applied adsorption isotherms and kinetic models for phosphate adsorption. SEM analysis was conducted to examine the INTs surface formation. Further XRD and XPS analysis were performed to observe the crystal structure of INTs before and after phosphate adsorption. AFM analysis was conducted to determine of Fe foil surface before and after anodization. Phosphate stock solution for adsorption experiment was prepared by KH2PO4. The batch experiment was conducted using 20 ml phosphate stock solution and 40 cm3 of INTs in 50 ml conical tube. Adsorption isotherms were applied Langmuir and Freundlich models for adsorption equilibrium test of INTs. Pseudo first order and pseudo second order models were applied for interpretation of adsorption rate by reaction time. The determination coefficient (R2) values of Langmuir and Freundlich models were 0.9157 and 0.8876 respectively.

Polymeric materials have been widely used in energy-related applications including fabrication of batteries and fuel cells, pressure retarded osmosis, gas separation and reverse electrodialysis processes. Despite these various versatility, their poor mechanical properties still remain as obstacles for applying to industrial levels. As a way of improving the mechanical properties, Tröger's Base (TB) which is a rigid, V-shaped, and bridged bicyclic amine have been recently introduced. In this work, polyimides incorporating TB units (PI-TBs) were synthesized in-situ polycondensation reaction using dimethoxymethane (DMM). PI-TB membranes were prepared and physicochemical characteristics including mechancial properties were investigated.

The aim of this study was to evaluate effect of α-linolenic acid (ALA) on viability, acrosome reaction and mitochondrial intact in frozen-thawed boar sperm. The boar semen was collected by gloved-hand method and cryopreserved in 20% egg yolk freezing extender containing ALA (0, 3, 5, and 10 ng/mL) with 0.05% ethanol. The frozen-boar spermatozoa were thawed at 37.5°C for 45 sec in water-bath. The spermatozoa samples were evaluated the plasma membrane integrity, acrosome reaction, and mitochondrial integrity using flow cytometry. In results, population of live sperm with intact plasma membrane was significantly higher in control and 3 ng/mL ALA treatment group than ethanol group (p<0.05). In contract, dying sperms were higher in ethanol group than 3 ng/mL ALA treatment (p<0.05). Acrosomal membrane damage in all sperm population was reduced in 3 ng/mL ALA groups compared with ethanol treatment (p<0.05). However, acrosome damage in live sperm population was no significant difference among the all treatment groups. Mitochondrial integrity was not influenced by ALA treatments in both of live and all sperm population. In conclusion, this results show that supplement of ALA during the cryopreservation process could reduce the membrane damages including plasma and acrosomal membrane, whereas ALA did not influence to mitochondria in boar spermatozoa. Therefore, these results suggest that ALA can protect against the membrane damage derived cryo-stress, and cryopreservation efficiency of boar semen would be improved by use of ALA.

Rice is the most important staple food and the consumption is increasing in Europe and America. It is expected that the rice price will be increased due to the unstable supply and demand because of abiotic stress. Experts expect that the rice supply of Korea will be deficient in 2050 for the reason of global warming. Conventional breeding methods need to be supplemented with recent biotechnology to meet the problem such as growing population and climate change. Using rice biotechnology, a number of agronomically important traits and nutritional value have been improved. In this paper, the current situation of rice cultivation and production situation and supply and consumption in the major country were investigated to prepare future food security. Also the research trends of rice biotechnology and kinds of transformed rice as well as safety issues were reviewed by considering the scientific, social and economic values of rice.

This study was carried out for characterization of MIO synthesized in our laboratory by co-precipitation method and applied isotherm and kinetic models for adsorption properties. XRD analysis were conducted to find crystal structure of synthesized MIO. Further SEM and XPS analysis was performed before and after phosphate adsorption, and BET analysis for surface characterization. Phosphate stock solution was prepared by KH2PO4 for characterization of phosphate adsorption, and batch experiment was conducted using 50 ml conical tube. Langmuir and Freundlich models were applied based on adsorption equilibrium test of MIO by initial phosphate solution. Pseudo first order and pseudo second order models were applied for interpretation of kinetic model by temperature. Surface area and pore size of MIO were found 89.6 m2/g and 16 nm respectively. And, the determination coefficient (R2) value of Langmuir model was 0.9779, which was comparatively higher than that of Freundlich isotherm model 0.9340.

Porous metallic glass compact (PMGC) are developed by electro-discharge sintering (EDS) process of gas atomized Zr41.2Ti13.8Cu12.5Ni10Be22.5 metallic glass powder under of 0.2 kJ generated by a 450 μF capacitor being charged to 0.94 kV. Functional iron-oxides are formed and growth on the surface of PMGCs via hydrothermal synthesis. It is carried out at 150oC for 48hr with distilled water of 100 mL containing Fe ions of 0.18 g/L. Consequently, two types of iron oxides with different morphology which are disc-shaped Fe2O3 and needle-shaped Fe3O4 are successfully formed on the surface of the PMGCs. This finding suggests that PMGC witih hydrothermal technique can be attractive for the practical technology as a new area of structural and functional materials. And they provide a promising road map for using the metallic glasses as a potential functional application.

본 연구는 계방산 가문비나무 및 전나무 임분의 산림식생유형분류와 정량적 분석을 위하여 Z-M 식물사회학적 방법으로 식생구조의 유형분류를 실시한 결과, 군락단위에서 가문비나무군락, 전나무군락으로 분류되었으며 가문비나무군락은 군단위에서 흰인가목군과 부게꽃나무군으로 세분되었으며, 전나무군락은 복장나무군과 생강나무군으로 세분되었다. 분류된 식생단위를 기준으로 중요치를 산출한 결과, 가문비나무는 식생단위 1과 2의 교목층에서 각각 30.73%, 20.25%로 비교적 높게 나타나 당분간 가문비나무의 우점이 계속될 것이라 판단되었다. 또한 종다양도를 분석한 결과 식생단위 4의 종다양도 지수는 0.6976으로 가장 낮았으며, 식생단위 2의 종다양도 지수는 1.1256으로 가장 높게 나타났다. 군락간의 유사도는 식생단위 1과 4, 2와 4가 각각 0.2880과 0.3626으로 낮게 나타났으며 식생단위 1과 2, 3과 4의 군락유사성은 각각 0.5411과 0.5041로 나타나, 군락 간 구성종의 차이가 크지 않은 군락으로 판단되었다. 종간연관에 대한 Chi-square matrix와 성좌표를 각각 분석한 결과, 크게 2개의 유형으로 나뉘어졌는데 Ⅰ유형의 식물 종들은 대부분 식물사회학적으로 분류된 가문비나무군락에서 주로 출현하는 식별종과 표징종이었으며, Ⅱ유형의 식물종은 전나무군락에서 주로 출현하는 식물종으로, 비교적 습한 곳에 나타나는 종들로 나뉘어졌다. 이러한 결과는 각 수종들이 선호하는 생육환경이 비슷한 종들끼리는 정의 상관이 인정되고, 선호하는 환경이 다른 종들끼리는 부의 상관을 보이는 것으로 판단된다.