North Korea has repeatedly provoked using unmanned aerial vehicles (UAVs), and the threat posed by UAVs continues to escalate, as evidenced by recent directives involving the use of waste-laden balloons and the development of suicide drones. North Korea’s small UAVs are difficult to detect due to their low radar cross-section (RCS) values, necessitating the efficient deployment and operation of assets for effective response. Against this backdrop, this study aims to predict the infiltration routes of enemy UAVs by considering their perspective, avoiding key facilities and obstacles, and propose deployment strategies to enable rapid detection and response during provocations. Utilizing the Markov Decision Process (MDP) based on previous studies, this research presents a model that reflects both UAV flight characteristics and regional environments. Unlike previous models that designate a single starting point, this study addresses the practical challenge of uncertainty in initial infiltration points by incorporating multiple starting points into the scenarios. By aggregating and integrating the probability maps derived from these variations into a unified map, the model predicts areas with a high likelihood of UAV infiltration over time. Furthermore, based on case studies in the capital region, this research proposes deployment strategies tailored to the specifications of currently known anti-drone integrated systems. These strategies are expected to support military decision-making by enabling the efficient operation of assets in areas with a high probability of UAV infiltration.
The risk of inflammatory conditions caused by obesity is associated with an increased predisposition for additional pathological conditions, including cardiovascular risk factors. Adipose tissue stores energy and contributes to endocrine and immune functions that regulate homeostasis throughout the body. The effects of honokiol on vascular homeostasis in adipose tissue in high-fat diet (HFD)-induced obese mice are unclear. This study examined the protective effect of honokiol, an extract of traditional alkaloid herbs, on vascular endothelial cells in epididymal adipose tissue (EAT) and its regulatory effect on other metabolic parameters, such as the lipid droplet diameter, macrophage infiltration, and inflammation in HFDinduced obese mice. A HFD increased the density of platelet endothelial cell adhesion molecule-1 (PECAM-1)-1-positive vascular endothelial cells in EAT, which was decreased significantly by the honokiol treatment. Honokiol ameliorated the HFD-induced increase in lipid droplet diameter and increased macrophage infiltration in adipose tissue. Honokiol ameliorated the up-regulation of pro-inflammatory molecules and F4/80-positive macrophage infiltration in the adipose tissue of HFD-induced obese mice. Obese mice administered honokiol exhibited reduced mRNA expression of M1 macrophage (F4/80, TNF-, mIL-1, CD11c, and CCL2) and M2 macrophage (Arginase-1, FIZZ1, CD206, and TGF-1) markers in EAT. The vascular permeability was detected by Evans blue dye leakage in EAT of obese mice and treated mice with honokiol. These data suggest that honokiol regulates the angiogenic effects in adipose tissue and inflammation in HFDinduced obese mice.
The current study was intended to synthesize and characterize the physical, chemical, and mechanical properties of carbon/ carbon (C/C) composites using the chemical vapor infiltration (CVI) process. To that end, carbon fiber felt (CF) was used as a preform, and methane and hydrogen were employed as reactive and carrier gases, respectively. After deciding on the optimum temperature (1050 °C), the composite samples were produced at different times (0–195 h). Then the samples were studied for their phase and microstructure characteristics using XRD, SEM, FESEM, FTIR, and Raman spectroscope. The results showed that by increasing the CVI process time up to 195 h, the density of the produced samples increased from 0.20 to 1.62 g/cm3, and the specific surface area decreased from 58.78 to 0.23 m2/ g. Also, by increasing the process duration, the deposition rate decreased due to the reduction of the available surface for carbon deposition. In other words, due to the increase in density, and decrease in both porosity and specific surface area, the thermal conductivity coefficient and the bending strength of the samples increased. The composite specimens’ SEM images of the fracture surface indicated a weak interface between the carbon fibers and the carbon layer developed by the CVI process. The structural analyses showed that the morphology of carbon growth during the CVI process was initially laminar, but changed to rough-laminar (RL) with the higher duration of the CVI process.
The conversion of all carbon preforms to dense SiC by liquid infiltration can become a low-cost and reliable method to form SiC-Si composites of complex shape and high density. Reactive sintered silicon carbide (RBSC) is prepared by covering Si powder on top of 0.5-5.0 wt% Y2O3-added carbon preforms at 1,450 and 1,500°C for 2 hours; samples are analyzed to determine densification. Reactive sintering from the Y2O3-free carbon preform causes Si to be pushed to one side and cracking defects occur. However, when prepared from the Y2O3-added carbon preform, an SiC-Si composite in which Si is homogeneously distributed in the SiC matrix without cracking can be produced. Using the Si + C = SiC reaction, 3C and 6H of SiC, crystalline Si, and Y2O3 phases are detected by XRD analysis without the appearance of graphite. As the content of Y2O3 in the carbon preform increases, the prepared RBSC accelerates the SiC conversion reaction, increasing the density and decreasing the pores, resulting in densification. The dense RBSC obtained by reaction sintering at 1,500 oC for 2 hours from a carbon preform with 2.0 wt% Y2O3 added has 0.20% apparent porosity and 96.9% relative density.
The conversion of carbon preforms to dense SiC by liquid infiltration is a prospectively low-cost and reliable method of forming SiC-Si composites with complex shapes and high densities. Si powder was coated on top of a 2.0wt .% Y2O3-added carbon preform, and reaction bonded silicon carbide (RBSC) was prepared by infiltrating molten Si at 1,450oC for 1-8 h. Reactive sintering of the Y2O3-free carbon preform caused Si to be pushed to one side, thereby forming cracking defects. However, when prepared from the Y2O3-added carbon preform, a SiC-Si composite in which Si is homogeneously distributed in the SiC matrix without cracking can be produced. Using the Si + C → SiC reaction at 1,450oC, 3C and 6H SiC phases, crystalline Si, and Y2O3 were generated based on XRD analysis, without the appearance of graphite. The RBSC prepared from the Y2O3-added carbon preform was densified by increasing the density and decreasing the porosity as the holding time increased at 1,450oC. Dense RBSC, which was reaction sintered at 1,450oC for 4 h from the 2.0wt.% Y2O3-added carbon preform, had an apparent porosity of 0.11% and a relative density of 96.8%.
This research combines the liquid carbon precursor infiltration process for carbon/carbon composites with the fabrication procedure for organic, carbon-matrix friction materials in automotive. In the densification process, different liquid carbon precursors and numbers of densification cycle are adopted to investigate the influence on physical and mechanical properties, microstructure and tribological behavior. Experimental results indicate that the infiltration of liquid carbon precursors could improve the physical, mechanical properties and tribological performances of organic friction materials. The open porosity decreases with the number of densification cycle. Both bulk density and hardness increase with the number of densification cycle. The resin-based specimens show higher hardness and lower open porosity than those of the pitch-based specimens after each densification cycle. The tribological measurement of specimens with different carbon precursors shows that the pitch-based specimen shows lower and more stable friction coefficients and exhibits lower weight losses in comparison with other carbon precursors. Morphological observations show that a large area of smooth lubricative film was easily presented on the worn surfaces of the pitch-based specimens, whereas it was seldom observed on the worn surfaces of the preform specimen and resin-based specimens.
The purpose of this study was to analyze the effects of sewerage facilities through I/I analysis by rainfall by selecting areas where storm overflow diverging chamber is remained due to the non-maintenance drainage equipment when the sewerage system was reconstructed as a separate sewer system. Research has shown that wet weather flow(WWF) increased from 106.2% to 154.8% compared to dry weather flow(DWF) in intercepting sewers, and that the WWF increased from 122.4% to 257.6% in comparison to DWF in storm overflow diverging chamber. As a result, owing to storm overflow diverging chamber of partially separate sewer system with untreated tributary of sewage treatment plant, rainfall-derived infiltration/inflow(RDII) has been analyzed 2.7 times higher than the areas without storm overflow diverging chamber. Meanwhile, infiltration quantity of this study area was relatively higher than that of other study areas. Therefore, it is necessary to reduce infiltration quantity through sewer pipe maintenance nearby river. Drainage equipment maintenance should be performed not to operate storm overflow diverging chamber in order to handle the appropriate sewage treatment plant capacity for rainfall because it is also expected that RDII due to rain will occur after maintenance. In conclusion, it is necessary to recognize aRDII(allowance of rainfall-derived infiltration/inflow) and to be reflected it on sewage treatment plant capacity because aRDII can occur even after maintenance to the complete separate sewer system.
In this study, a thermal-gradient chemical vapor infiltration (TG-CVI) process was numerically studied in order to enhance the deposition uniformity within the preform. The computational fluid dynamics technique was used to solve the governing equations for heat transfer and gas flow during the TG-CVI process for two- and three-dimensional (2-D and 3-D) models. The temperature profiles in the 2-D and 3-D models showed good agreement with each other and with the experimental results. The densification process was investigated in a 2-D axisymmetric model. Computation results showed the distribution of the SiC deposition rate within the preform. The results also showed that using two-zone heater gave better deposition uniformity.
PURPOSES : This study mechanically analyzed the performance of road substructures with focus on infiltration trenches of pavement substructures. METHODS: Water contents and response times for precipitation of pavement substructures were investigated via sensors buried near the infiltration trench to measure water contents. RESULTS : The results of the water contents of pavement systems constructed with an infiltration trench yield levels that were slightly increased by approximately 2% compared to those measured from general pavement systems. This water content difference of 2% resulted in a decrease in service life of less than two years. CONCLUSIONS: Service life reduction due to an infiltration trench is minimal, particularly when the trench is installed with proper caution.
Metal matrix composites(MMC) can obtain mechanical characteristics of application purposes that a single material is difficult to obtain. Al2 O3/AC8A composites were fabricated by low pressure infiltration process. The purpose is establishing the optimal casting conditions for composite preparation under low pressure. It is known the inorganic binder help infiltration. Therefore Al2O3 fiber preform's optimum sinter temperature is 1160℃, added inorganic binder is mixed binder(SiO2 sol:Al2O3 sol=5:2). And three fibers have been compared (Al2O3 80%/SiO2 20%, Al2O3 80%/SiO2 10% and Al2O3 97%/SiO2 3%). Al2O3/AC8A composites was made by each melting temperatures(650℃, 700℃, 750℃) and wear test was performed about effect of temperatures, kind of fiber, matrix and composites, aging time. Wear test is Ball on disk wear test. The resistance increased with the low melting temperature and Al2O3 80%/SiO2 20% fiber.
Ni and Ni-Cr reinforced Al alloy (AC8A) composites were fabricated by low pressure infiltration process. Porous Ni was applied as preform. Ni reinforced AC8A composites were fabricated under 0.3 MPa at 650, 700 and 750 degrees centigrade, respectively, while Ni-Cr reinforced AC8A composites were fabricated under low pressure limited to the maximum of 0.5 Mpa at 750, 800 and 850 degrees centigrade, respectively. Microstructure and phase composition of the composites were evaluated by optical microscope, X-Ray diffraction (XRD), electro-probe micro analyzer (EMPA). Intermetallic compounds Al3Ni and CrSi were observed in the composites. The results indicate that the grain size has been increasing with the increase of the infiltration temperatures. However, the wear resistance of Ni/AC8A and Ni-Cr AC8A peaked at 650 degree centigrade and 800 degrees centigrade, respectively. In addition, based on the wear characteristics and wear surfaces, Ni-Cr/AC8A composites have a better wear resistance than Ni/AC8A composites and AC8A.
온실의 난방부하 중 틈새환기전열부하 산정방법은 설계 기준마다 제각각이고, 온실의 규모에 따라 각각의 방법에는 큰 차이가 있으므로 보다 정확히 국내에 적용할 수 있는 방법을 정립할 필요가 있다. 본 연구에서는 원예시설의 환경설계 중 난방부하 산정방법 정립에 필요한 기초자료를 제공할 목적으로 다양한 종류의 보온커튼을 설치한 단동 및 연동 플라스틱 온실에서 추적가스법을 이용하여 틈새환기율을 실측하였으며, 온실의 틈새환기 전열부하 산정방법을 검토하였다. 연동온실의 틈새환기 율은 0.042~0.245h-1의 범위로 측정되었으며 단동온실의 틈새환기율은 0.056~0.336h-1의 범위로 측정되어 단동온 실이 약간 큰 것으로 나타났다. 온실의 틈새환기율은 단동, 연동 구분없이 보온커튼의 층수에 따라 크게 감소하는 것으로 나타났다. 또한 틈새환기율은 온실의 실내외 기온차가 커질수록 증가하는 경향을 보였으나, 실험기간 동안의 낮은 풍속 범위에서 외부 풍속에 따른 틈새환기 율의 변화는 일정한 경향을 찾을 수 없었다. 온실의 난방설계를 위한 틈새환기율은 적정 실내외 기온차에서의 값을 제시할 필요가 있고, 최대난방부하 산정의 기준이 되는 낮은 풍속 범위에서 풍속에 따른 틈새환기율의 변화는 고려하지 않아도 되는 것으로 고찰되었다. 다만 강 풍지역에서는 열관류율을 포함하여 최대난방부하를 약간 증가시키는 보정계수의 적용이 필요할 것으로 판단되었다. 온실의 틈새환기전열부하 산정방법을 검토한 결과 틈새환기전열계수와 온실의 피복면적을 이용하는 방법은 문제가 있는 것으로 나타났으며, 틈새환기율과 온실의 체적을 이용하는 방법이 합리적인 것으로 판단되었다.
담배가루이(Bemisia tabaci)는 난방제 해충으로 살충제를 이용한 화학적 방제를 포함한 여러 가지 방법으로 방제를 수행하고 있다. 이러한 다양한 방법 가운데 하나로 담배가루이를 방제하기 위하여 RNA interference(RNAi)를 이용하려고 한다. 이를 위하여 본 연구에서는 RNAi에 이용하기 위한 target유전자를 선발하기 위해 담배가루이 cDNA library를 제작하였고, 완성한 cDNA library는 Tobacco rattle virus(TRV) RNA2 vector에 LR recombination한 다음, Agrobacterium tumefaciens(GV2260)에 transformation하였다. A. tumefaciens(GV2260)에 transformation된 cell은 토마토에 Agro-infiltration시킨 후, TRV RNA2 vector의 CP detection을 통해 접종되었는지 확인하였다. 그 결과, unknown유전자가 삽입된 TRV RNA2 vector 27개 대부분과 control로 사용된 TRV original vector가 접종된 것으로 확인되었다. 접종이 확인된 유전자는 토마토에 Agro-infiltration시킨 후 담배가루이가 섭식하였을 때, RT-qPCR을 통해 담배가루이 체내에서의 유전자발현량의 감소를 측정하고, 유전자 감소에 의한 살충 또는 기피효과가 나타나는지 행동학적 변화로 확인하고자 한다. 이는 RNAi적용에 적합한 target유전자를 선발할 수 있을 것으로 사료된다.
The purpose of this study is to analyze the structural stability of pavement due to water infiltration at the road with infiltration trench as using the FEM(finite element analysis). Five cases for FEM is divided considering the amount of rainfall and rain duration time. The results of FEM show that the more rainfall in a short period time is faster the change of moisture content. Also, it is the proportional relationship between and changing area of moisture content of more than 40% due to rainfall. Case 3 and 4 are necessary to check the installation of infiltration trench because of moisture content of more than 40%, recovery time of initial moisture content, and changing area of more than 40%. Case 1,2, and 5 have no a significant effect on road pavement structure due to lower moisture content and shorter duration time of higher moisture content.
In this study, current sewer infiltration/Inflow(I/I) computation and application method was examined about improvement and adequacy relating to the main issues raised by the field for practitioners. The results of review about infiltration calculation method were considered to be in need of improvement at‘standards of minimum sewage calculation’. Furthermore, the results of review about I/I application method were considered to be in need of improvement at‘standards of seasonal infiltration application’and‘the relative decrease in the Annual evaluation standards’. In addition, annual I/I analysis at JC County for the four years(2009 ~ 2012) in respect of operation flow and rainfall data was conducted. The result of annual infiltration analysis, compared average daily sewage generated average infiltration rate was found in 21.95 %, infiltration by unit was found in 0.31 m3/day/cm/km and 0.12 m3/day/day, respectively. The result of annual inflow analysis, average rainfall - Inflow equations was found y = 5.499x(R2 0.793), and the average Inflow quantity by sewer extension was predicted to 0.66 m3/mm-km.
Chronic hyperplastic candidiasis (CHC) is characterized by epithelial hyperplasia of the oral mucosa associated with candidal hyphae. The immune status of host is one of the factors that induce clinically evident candidal infection. Host defense mechanisms include inflammatory cells, epithelial barrier, and antimicrobial peptides such as human beta 2 defensin (hBD-2). In the present study, we investigated the densities of CD4+/CD8+ T lymphocytes and hBD-2 expression of epithelial cells in CHC. Immunohistochemical staining was performed on 10 cases of CHC using CD4, CD8 and hBD-2. Ten specimens of chronic mucositis were selected for comparison, and went through the same examination. hBD-2 was expressed in the spinous cell layers and the keratin layers of 7 CHC patients, while the epithelium of chronic mucositis did not demonstrate the hBD-2 expression except for one case. Also, hBD-2 expression was stronger when the hyphae invaded the upper stratum spinosum (P =.019). However, the densities of CD8+ T lymphocytes were significantly lower in the CHC patients, suggesting that the ability of CD8+ T cells to enter the epithelium and target the pathogenic hyphae was decreased in CHC. Increased hBD-2 expression seemed to be significantly associated with the candidal infection, while not promoting the cell-mediated immune reaction in CHC.
This study aims to overview and review the infiltration of Japanese Buddhism and it's influences on the construction and architectural characteristics of Japanese Buddhist temple from the opening of ports to Independence Day of Korea. Infiltration of Japanese Buddhism had been sustained during 70 years from the foundation of Higashi Hongan-ji Temple(東本願寺) in Pusan, by Shinshu Otani School(真宗大谷派) which was one of Japanese Buddhism, to Independence Day of Korea. This study is to be promoted on the following subjects ; 1) the circumstance around the infiltration of Japanese Buddhism 2) Buddhism policy of Japanese Governor and infiltration on Korean Buddhism 3) increasing trend, distribution and construction of Japanese Buddhist temples near downtown areas 4) for the conclusion, case research on Bondang, Gori, and open space and analysis on the architecture style of Japanese Buddhist temples Accordingly, Korean Buddhism had been subordinated to Japanese Buddhism, and the management system and memorial service of Korean Buddhism had to be affected by Japanese Buddhism. This study is considered meaningful for the elementary research to examine the aspects of Japanese style on Korean Buddhist architecture at that time.
C/SiC composites were prepared by boron nitride (BN)-assisted liquid silicon infiltration (LSI), and their anti-oxidation and mechanical properties were investigated. The microstructures, bulk densities, and porosities of the C/SiC composites demonstrated that the infiltration of liquid silicon into the composites improved them, because the layered-structure BN worked as a lubricant. Increasing the amount of BN improved the anti-oxidation of the prepared C/SiC composites. This synergistic effect was induced by the assistance of BN in the LSI. More thermally stable SiC was formed in the composite, and fewer pores were formed in the composite, which reduced inward oxygen diffusion. The mechanical strength of the composite increased up to the addition of 3% BN and decreased thereafter due to increased brittleness from the presence of more SiC in the composite. Based on the anti-oxidation and mechanical properties of the prepared composites, we concluded that improved anti-oxidation of C/SiC composites can be achieved through BN-assisted LSI, although there may be some degradation of the mechanical properties. The desired anti-oxidation and mechanical properties of the composite can be achieved by optimizing the BN-assisted LSI conditions.
A highly porous Biphasic Calcium Phosphate (BCP) scaffold was fabricated by the sponge replica method with a microwave sintering technique. The BCP scaffold had interconnected pores ranging from 80 μm to 1000 μm, which were similar to natural cancellous bone. To enhance the mechanical properties of the porous scaffold, infiltration of polycaprolactone (PCL) was employed. The microstructure of the BCP scaffold was optimized using various volume percentages of polymethylmethacrylate (PMMA) for the infiltration process. PCL successfully infiltrated into the hollow space of the strut formed after the removal of the polymer sponge throughout the degassing and high pressure steps. The microstructure and material properties of the BCP scaffold (i.e., pore size, morphology of infiltrated and coated PCL, compressive strength, and porosity) were evaluated. When a 30 vol% of PMMA was used, the PCL-BCP scaffold showed the highest compressive strength. The compressive strength values of the BCP and PCL-BCP scaffolds were approximately 1.3 and 2MPa, respectively. After the PCL infiltration process, the porosity of the PCL-BCP scaffold decreased slightly to 86%, whereas that of the BCP scaffold was 86%. The number of pores in the 10 μm to 20 μm rage, which represent the pore channel inside of the strut, significantly decreased. The in-vitro study confirmed that the PCL-infiltrated BCP scaffold showed comparable cell viability without any cytotoxic behavior.