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Structural analysis, based on a global ship model, is vital for examining the structural strength and safety of a hull. In the “NASTRAN” global ship model, only the structural members and cargo tank of a ship are modeled and the outfit, electric system, and other tanks and liquid are omitted from the model. The additional weight of these omitted elements, however, constitutes part of the light weight of the ship and must be considered in conducting an accurate structural analysis of the ship. Generally, the weight of these omitted elements is calculated using the trim and stability information of the ship and is then added to the model. In such cases, the center of gravity of the global ship model, which now includes the weight of these omitted elements, must be adjusted to the target center of gravity required for the analysis. In this study, an algorithm was developed to satisfy the target center of gravity while distributing the weight of these omitted elements to the global ship model using Gaussian elimination. The algorithm was developed using C#, and its accuracy was verified by applying it to the global ship models.

This paper deals with free vibrations of the axially functionally graded (AFG) horseshoe arch. The modulus of elasticity and the mass density of AFG material of arch are chosen as a univariate quadratic function. The differential equations with the boundary conditions that govern the free vibration of such arch are derived and numerically solved to calculate natural frequencies and mode shapes. Natural frequencies of this study agree well with those of the finite element ADINA. Parametric studies of the geometrical and mechanical properties of the arch on frequencies and mode shapes are performed and extensively discussed.

L-ascorbic acid (L-AA; vitamin C) induces apoptosis in cancer cells. This study aimed to elucidate the molecular mechanisms of L-AA-induced apoptosis in human laryngeal epidermoid carcinoma Hep-2 cells. L-AA suppressed the viability of Hep-2 cells and induced apoptosis, as shown by the cleavage and condensation of nuclear chromatin and increased number of Annexin V-positive cells. L-AA decreased Bcl-2 protein expression but upregulated Bax protein levels. In addition, cytochrome c release from the mitochondria into the cytosol and activation of caspase-9, -8, and -3 were enhanced by L-AA treatment. Furthermore, apoptosis-inducing factor (AIF) and endonuclease G (EndoG) were translocated into the nucleus during apoptosis of L-AA-treated Hep-2 cells. L-AA effectively inhibited the constitutive nuclear factor-κB (NF-κB) activation and attenuated the nuclear expression of the p65 subunit of NF-κB. Interestingly, L-AA treatment of Hep-2 cells markedly activated Akt and mitogen-activated protein kinase (MAPK; extracellular signal-regulated kinase 1/2, p38, and c-Jun N-terminal kinase [JNK]) and and LY294002 (Akt inhibitor), SB203580 (p38 inhibitor) or SP600125 (a JNK inhibitor) decreased the levels of Annexin V-positive cells. These results suggested that L-AA induces the apoptosis of Hep-2 cells via the nuclear translocation of AIF and EndoG by modulating the Bcl- 2 family and MAPK/Akt signaling pathways.

최근 전력 수요가 급증하는 상황에서 많은 에너지 관련 연구들이 대체에너지 개발, 전력사용의 절감과 효율, 전력 사용의 시간차 분산 그리고 에너지 저장기술 등을 다루고 있다. 본 연구에서는 한 생산시설에서 수집된 전력사용량 시계열 데이터를 분석하면서 Peak 전력사용량과 그 시간대를 예측에 대한 중요성을 인지하였다. 이는 상시전력과 대체전력간의 전환, 에너지 거래 등에 있어서 필수적인 예측분석이기 때문에 더욱 실효성을 높일 수 있는 결과 도출을 위해 24시간의 단기 예측을 분석 목표로 설정하였다. 본 논문에서 수행한 시계열 분석방법으로 SARIMA모형과 계정성지수평화법이 사용되었고 이러한 분석모델이 향후 V2G 또는 ESS 관련된 현업에서 활용과 확장이 될 수 있도록 기대한다.

Recent studies have revealed that protein arginine methyltransferases (PRMTs) are responsible for diverse neurodegenerative diseases. However, their pathophysiological role in dopaminergic neuronal death in Parkinson's disease (PD) has not been evaluated. In this study, we demonstrated that 1-Methyl-4-phenylpyridinium iodide (MPP+), rotenone and paraquat, which cause dopaminergic neuronal cell death, increased PRMT1 expression in dopaminergic cell line. Dopaminergic neuronal cell death was increased by PRMT1 overexpression. MPP+-induced cell death was attenuated by PRMT1 knockdown. Poly (ADP-ribose) polymerase-1 (PARP1) expression and activity, poly-ADP-ribosylation (PARylation), were elevated by MPP+. Moreover, we found that PRMT1 positively regulates nuclear translocation of apoptosis-inducing factor (AIF). Elevated PRMT1 expression was observed in the substantia nigra pars compacta of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-injected mice. Furthermore, MPTP-induced dopaminergic neuronal death was reduced in PRMT1 haploinsufficient (prmt1+/-) mice. These data suggest that PRMT1 is implicated in PARP1/AIF-mediated dopaminergic neuronal cell death, which might be involved in the pathology of PD. Therefore, our results propose PRMT1 as a new target to develop a potential treatment of PD.

Deep neural networks (DNNs) gained in popularity as an effective machine learning algorithm, but their high complexity leads to the lack of model interpretability and difficulty in the verification of deep learning. Fuzzing, which is an automated software testing technique, is recently applied to DNNs as an effort to address these problems by following the trend of coverage-based fuzzing. However, new coverage metrics on DNNs may bring out the question of which layer to measure the coverage in DNNs. In this poster, we empirically evaluate the performance of existing coverage metrics. By the comparative analysis of experimental results, we compile the most effective layer for each of coverage metrics and discuss a future direction of DNN fuzzing.

1994년 유엔해양법 발효 이후 해양활동의 무대가 배타적 경제수역과 대륙붕까지 확대됨에 따라 각국은 자국의 권리를 강화해 나가고 있으며 국제사회는 국익을 확보하려는 다툼이 더욱 치열해지고 있다. 이와 관련하여 해양주권에 대한 연구가 많이 이루어졌으나 정책적인 연구에만 국한 되었을 뿐 실증적인 연구는 전무한 실정이다. 따라서 본 연구에서는 해양주권에 대한 실증적 인구를 위해 최근 빈번히 발생하고 있는 중국어선이 불법조업 사례를 대상으로 연구를 실시하였다. 해양주권 침해의 요인이 되는 요소를 선정하여 상관분석과 다중 회귀분석을 실시하였으며 또한 해양주권 침해의 경제적 파급영향을 분석하였다. 분석결과, 중국의 수산물 증가로 인해 발생한 중국 불법조업의 중가는 우리나라의 수산물 생산량을 감소시켰으며 이는 우리나라 어가 경제에 손실을 미쳤을 뿐만 아니라 우리나라 가계 경제에도 큰 부담을 초래 하였다.

In the shipbuilding industry, the non-destructive testing for welding quality inspection is mainly used for the permanent storage of the testing results and the radio-graphic testing which can visually inspect the interior of the welded part. Experts are required to properly detect the test results and it takes a lot of time and cost to manually Interpret the radio-graphic testing image of the structure over 500 blocks. The algorithms that automatically interpret the existing radio-graphic testing images to extract features through image pre-processing and classify the defects using neural networks, and only partial automation is performed. In order to implement the feature extraction and classification in one algorithm and to implement the overall automation, this paper proposes a method of automatically detecting welding defect using Faster R-CNN which is a deep learning basis. We analyzed the data to learn algorithms and compared the performance improvements using data augmentation method to artificially increase the limited data. In order to appropriately extract the features of the radio-graphic testing image, two internal feature extractors of Faster R-CNN were selected, compared, and performance evaluation was performed.

The conductive nanomaterials applicable to unconventional printing techniques have attracted a great deal of attention, and in particular, cost-effective copper-based electrode materials have been recognized as viable candidates for replacement of the expensive silver counterpart. In this study, we synthesize newly designed Cu/Cu10Sn3 core/shell nanoparticles, as an additive material for overcoming the critical drawbacks in Cu nanoparticle-based electrodes, in combination with a large-area processable, continuous photonic sintering process on a time scale of 10–3 s. By virtue of the low-melting point nature of the Cu10Sn3 phase, the facile electrode fabrication process is easily triggered, yielding resistivities of 27.8 and 12.2 μΩ cm under energy dose conditions of 0.97 and 1.1 J/cm2, respectively, at which highly conductive electrodes cannot be obtained from phase-pure Cu nanoparticles. The suspension mixture of Cu and Cu/Cu10Sn3 nanoparticles permits roll-to-roll processable, highly uniform Cu-based el...

The pile-cap connection part which transfers foundation loads through pile body is critical element regarding flexural and shea r force because the change of area, stress, and stiffness occurs in the this region suddenly. The purpose of this study is to investigate the s tructural behavior of pile-cap connection dependent on fabrication methods using conventional PHC pile and composite PHC pile. A series of test under cyclic lateral load was performed and the connection behavior was discussed. From the test results, it was found that the initial rotational stiffness of pile-cap connection was affected by the length of pile-head inserted in footing and the location of longitudinal reinforcing bars. The types of pile an d location of longitudinal reinforcing bars governed the behavior of pile-cap connection regarding load-carrying capacity, ductility, and energy dissipati on.Keywords: Pile-cap connection, Cyclic lateral load, PHC pile, Composite PHC pile 1 정회원, 충남대학교 건설방재연구소 박사후 연구원

Traffic accident at intersections takes 44.3% of total number of accidents on entire road network of Korea in 2014. Although several studies addressed contributory factors of accidents at signalized intersection, very few is known about the factors at rural unsignalized intersections. The objective of this study is therefore to investigate specific characteristics of crashes at rural unsignalized intersection and to identify contributory factors in causing crashes by statistical approach using the Ordered Logistic Regression Model. The results show that main type of car crashes at unsignalized intersection during the daytime is T-bone crashes and the number of crashes at 4-legged intersections are 1.53 times more than that at 3-legged intersections. Most collisions are caused by negligence of drivers and violation of Right of Way. Based upon the analysis, accident severity is modeled as classified by two types such as 3-legged intersection and 4-legged intersection. It shows that contributory factors in causing crashes at rural unsignalized intersections are poor sight distance problem, average daily traffic, time of day(night, or day), angle of intersection, ratio of heavy vehicles, number of traffic violations at intersection, and number of lanes on minor street.Keywords: ordered logistic regression, safety, severity, traffic violation, unsignalized intersection

The present study is aimed at investigating the effects of the exogenous estrogen 17β-estradiol (E2) on odontoblastic differentiation in human dental pulp cells (HDPCs) immotalized with hTERT gene and their molecular mechanism. Proliferation was detected by BrdU assay, and odontoblast differentiation induction was evaluated by the expression of dentin sialophosphoprotein (DSPP), dentin sialoprotein (DSP) and dentin matrix protein1 (DMP1), and alkaline phosphatase (ALP) activity and mineralization. Estrogen receptor-α (ER-α), c-Src, and mitogen-activated protein kinases (MAPKs) were examined and their inhibitors were used to determine the roles on odontogenic induction. E2 significantly promoted the HDPC proliferation, which was mediated by extracellular signal-related kinase 1/2. E2 upregulated DSPP, DSP, and DMP1 as the odontogenic differentiation markers and enhanced ALP activity and mineralization. E2 increased phosphorylation of ER-α and fulvestrant, an ER downregulator, significantly downregulated DSPP, DMP1, and DSP induced by E2. Moreover, E2 treatment activated c-Src and MAPKs upon odontogenic induction, whereas chemical inhibition of c-Src and MAPKs decreased expression of DSPP, DMP1, and DSP and mineralization augmented by E2. Moreover, fulvestrant reduced E2-induced phosphorylation of c-Src and MAPK and inhibition of c-Src by PP2 attenuated activation of MAPKs during E2-induced odontoblastic differentiation. Taken together, these results indicated that E2 stimulates odontoblastic differentiation of HDPCs via coordinated regulation of ER-α, c-Src, and MAPK signaling pathways, which may play a key role in the regeneration of dentin.

This paper deals with planar free vibrations of the horseshoe elliptic uniform arch. Simultaneous differential equations governing free vibrations of such arch are derived, in which the axial extensional deformation is included and the radial and tangential deformations are normalized by the intercept of the horizontal axis. The differential equations are numerically solved for calculating natural frequencies with their corresponding mode shapes. In parametric studies, effects of the rotatory inertia, aspect ratio, subtended angle and slenderness ratio on frequency parameters are extensively discussed. Typical mode shapes of the radial and tangential deformations are presented in figures.

This paper presents free vibrations of the tapered horseshoe circular arch with a constant volume. The volume of the arch is constant, and the cross-sectional shape of the arch is square and circular. The taper function of the arch is a quadratic function. Differential equations with the boundary conditions that govern the free vibration of such arches are derived and numerically solved to calculate natural frequencies and mode shapes. The natural frequencies of this study agree well with those of the finite element ADINA. Parametric studies of the geometrical and cross-sectional properties of the arch on frequencies and mode shapes are performed and discussed.

Traditionally, optical proximity correction (OPC) on cell array patterns in memory layout uses simple bias rules to correct hierarchically-placed features, but requires intensive, rigorous lithographic simulations to maximize the wafer process latitude. This process requires time-consuming procedures to be performed on the full chip (excluding the cell arrays) to handle unique cell features and layout placements before (and even sometimes after) OPC. The time required limits productivity for both mask tapeouts and the wafer process development. In this paper, a new cell array OPC flow is introduced that reduces turnaround-time for mask tapeouts from days to hours, while maintaining acceptable OPC quality and the perfect geometric consistency on the OPC output that is critical for memory manufacturing. The flow comprises an effective sub-resolution assist features (SRAFs) insertion and OPC for both the cell array and the peripheral pattern areas. Both simulation and experimental results from actual wafer verification are discussed.

In this study, we suggest the chemical methodology that allows for the facile controllability of phase transformation between face-centered cubic and hexagonal close-packed structures for Ni nanoparticles with a 0.4–2 nm thick shallow surface oxide layer, resulting in a maximum saturation magnetization of 33.2 emu g−1. As a first proof-of-concept of the potential for the formation of flexible, printed magnetic devices on cost-effective polyethylene terephthalate (PET) and paper substrates, it is demonstrated that the resulting Ni nanoparticles, prepared in the form of magnetic fluids, are transformed into bulk-like patterned Ni architectures via air-brush printing and instant photonic annealing in a timescale of 10−3 s, exhibiting highly flexible properties under the harsh conditions of 10 000 times repeated bending tests.