• Earthquakes and Structures
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• 제26권5호
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• pp.401-416
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• 2024

Long-span structures, such as bridges, can experience different seismic excitations at the supports due to spatially variability of ground motion. Regarding current bridge designing codes, it is just EC 2008 that suggested some regulations to consider it and in the other codes almost ignored while based on some previous studies it is found that the effect of mentioned issue could not be neglected. The current study aimed to perform a comprehensive study about the effect of spatially varying ground motions on the dynamic response of a reinforced concrete bridge under asynchronous input motions considering soil-structure interactions. The correlated ground motions were generated by an introduced method that contains all spatially varying components, and imposed on the supports of the finite element model under different load scenarios. Then the obtained results from uniform and non-uniform excitations were compared to each other. In addition, the effect of soil-structure interactions involved and the corresponding results compared to the previous results. Also, to better understand the seismic response of the bridge, the responses caused by pseudo-static components decompose from the total response. Finally, an incremental dynamic analysis was performed to survey the non-linear behavior of the bridge under assumed load scenarios. The outcomes revealed that the local site condition plays an important role and strongly amplifies the responses. Furthermore, it was found that a combination of wave-passage and strong incoherency severely affected the responses of the structure. Moreover, it has been found that the pseudo-static component's contribution increase with increasing incoherent parameters. In addition, regarding the soil condition was considered for the studied bridge, it was found that a combination of spatially varying ground motions and soil-structure interactions effects could make a very destructive scenarios like, pounding and unseating.

• 한국산업정보학회논문지
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• 제29권2호
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• pp.81-99
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• 2024

최근, 실시간으로 스트리머와 소비자간 특정 제품에 대한 소통을 지원하는 라이브 커머스가 급격히 성장하고 있다. 라이브 커머스는 시각적으로 제품 활용 방법 등을 제공함으로써, 소비자의 합리적 제품 구매를 돕는 비즈니스 모델을 갖추고 있다. 연구의 목적은 소비자가 라이브 커머스에서 느낄 수 있는 불확실성 요소를 제시하고, 스트리머와 플랫폼의 불확실성 감소를 위한 지원 방법을 제시하는 것이다. 연구는 선행연구를 통해 연구 가설을 수립하였으며, 20세 이상의 라이브 커머스를 경험한 이력이 있는 소비자로부터 설문을 받아 가설 검정에 적용하였다. 분석 결과, 스트리머의 자원 원천 신뢰성(신뢰성, 전문성, 평판)이 스트리머 불확실성을 감소시켜 구매 의도에 영향을 주는 것으로 나타났다. 또한, 플랫폼의 반품정책이 소비자의 제품 불확실성과 상호작용 효과를 가져 구매 의도에 영향을 주었다. 연구는 라이브 커머스 소비자의 제품 구매 과정에서의 불확실성 감소 방향을 제시함으로써, 라이브 커머스 플랫폼의 맞춤형 서비스 전략 수립에 기여한다.

• Steel and Composite Structures
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• 제50권1호
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• pp.1-13
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• 2024

The objective of this research is to study experimentally and numerically the behavior of steel beam columns with openings. Although the presence of openings in the beam columns is inevitable, finding ways to maintain strength is crucial. The studied parameters are opening shape, the ratio between opening height to specimen height, the percentage of opening location from support to beam column length, and web slenderness. Experimental tests are conducted including twelve specimens to study the effect of these parameters and record failure load, load deflection curve, and stress strain curve. Two failure modes are observed: local and flexural buckling. Interaction curves plotted from finite element model analysis are also used to expand the parametric study. Changing the location of the opening can decrease failure load by up to 7% and 60% in both normal and moment ratios respectively. Increasing the opening dimension can lead to a drop in the axial ratio by up to 29% and in the moment ratio by up to 74%. The weakest beam column behavior is noticed in specimens with rectangular openings which results from uneven and concentrated stresses around the opening. The main results of this research illustrate that the best location for opening is at 40% - 50% from beam column support. Also, it is advisable to use circular openings instead of rectangular openings in specimens having slender webs because moment ratios are raised by 85% accompanied by a rise in normal ratios by 9%.

• 한국컴퓨터정보학회논문지
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• 제29권2호
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• pp.79-86
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• 2024

본 논문에서는 단일 영역 정보만을 활용하는 기존의 방법론을 개선하기 위해, 물체의 맥락영역에 대한 정보를 함께 물체 추적에 활용하는 새로운 기법을 제시한다. 기존의 방법론들은 모든 후보 영역들을 독립적으로 처리하는 구조로, 비슷한 외양의 영역들이 등장하는 경우 이를 성공적으로 구분하지 못하는 문제점을 보여주었다. 이는 주어진 장면 내에 등장하는 모든 후보 물체 영역들에 대한 맥락 정보를 고려하지 못하여 생기는 문제이다. 제안하는 방법론에서는 비슷한 외양의 영역들 간의 특징점 정보 교환을 보조하고 이들 간의 구별성을 높이는 것을 목표로 하였다. 이를 구현하기 위해 MLP-믹서 (MLP-Mixer) 모델을 활용하여 맥락영역 간의 정보 교환을 모델링하는 모듈을 제시하였다. 이를 통해 구현된 특징점 채널별, 영역간의 상호작용 연산은 영역의 개별 특징점 표현에 대해 장면 맥락 정보가 내장될 수 있도록 보조한다. 제안한 방법론의 성능을 평가하기 위해 대규모 물체 추적 데이터셋인 LaSOT을 사용하였고, 성능 평가 결과 제안한 알고리즘은 AUC 지표 기준 0.560의 높은 성능과 함께 65fps의 실시간 속도로 동작함을 확인하였다.

• 한국재료학회지
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• 제34권2호
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• pp.85-94
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• 2024

The optimization of deacetylation process parameters for producing chitosan from isolated chitin shrimp shell waste was investigated using response surface methodology with central composite design (RSM-CCD). Three independent variables viz, NaOH concentration (X₁), radiation power (X₂), and reaction time (X₃) were examined to determine their respective effects on the degree of deacetylation (DD). The DD of chitosan was also calculated using the baseline approach of the Fourier Transform Infrared (FTIR) spectra of the yields. RSM-CCD analysis showed that the optimal chitosan DD value of 96.45 % was obtained at an optimized condition of 63.41 % (w/v) NaOH concentration, 227.28 W radiation power, and 3.34 min deacetylation reaction. The DD was strongly controlled by NaOH concentration, irradiation power, and reaction duration. The coefficients of correlation were 0.257, 0.680, and 0.390, respectively. Because the procedure used microwave radiation absorption, radiation power had a substantial correlation of 0.600~0.800 compared to the two low variables, which were 0.200~0.400. This independently predicted robust quadratic model interaction has been validated for predicting the DD of chitin.

• Journal of Ginseng Research
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• 제48권4호
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• pp.373-383
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• 2024

Background: Network pharmacology has emerged as a powerful tool to understand the therapeutic effects and mechanisms of natural products. However, there is a lack of comprehensive evaluations of network-based approaches for natural products on identifying therapeutic effects and key mechanisms. Purpose: We systematically explore the capabilities of network-based approaches on natural products, using Panax ginseng as a case study. P. ginseng is a widely used herb with a variety of therapeutic benefits, but its active ingredients and mechanisms of action on chronic diseases are not yet fully understood. Methods: Our study compiled and constructed a network focusing on P. ginseng by collecting and integrating data on ingredients, protein targets, and known indications. We then evaluated the performance of different network-based methods for summarizing known and unknown disease associations. The predicted results were validated in the hepatic stellate cell model. Results: We find that our multiscale interaction-based approach achieved an AUROC of 0.697 and an AUPR of 0.026, which outperforms other network-based approaches. As a case study, we further tested the ability of multiscale interactome-based approaches to identify active ingredients and their plausible mechanisms for breast cancer and liver cirrhosis. We also validated the beneficial effects of unreported and top-predicted ingredients, in cases of liver cirrhosis and gastrointestinal neoplasms. Conclusion: our study provides a promising framework to systematically explore the therapeutic effects and key mechanisms of natural products, and highlights the potential of network-based approaches in natural product research.

• Biomolecules & Therapeutics
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• 제32권4호
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• pp.467-473
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• 2024

In this study, we investigated the potential protective effects of (+)-afzelechin (AZC), a natural compound that is derived from Bergenia ligulata, on lipopolysaccharide (LPS)-induced inflammatory responses. AZC is known to have antioxidant, anticancer, antimicrobial, and cardiovascular protective properties. However, knowledge regarding the therapeutic potential of AZC against LPS-induced inflammatory responses is limited. Thus, we investigated the protective attributes of AZC against inflammatory damage caused by LPS exposure. We examined the effects of AZC on heme oxygenase (HO)-1, cyclooxygenase (COX)-2, and inducible nitric oxide synthase (iNOS) in LPS-activated human umbilical vein endothelial cells (HUVECs). In addition, the effects of AZC on the expression of iNOS, tumor necrosis factor (TNF)-α, and interleukin (IL)-1β were analyzed in the lung tissues of LPS-injected mice. Data revealed that AZC promoted the production of HO-1, inhibited the interaction between luciferase and nuclear factor (NF)-κB, and reduced the levels of COX-2/PGE2 and iNOS/NO, thereby leading to a decrease in the signal transducer and activator of transcription (STAT)-1 phosphorylation. Moreover, AZC facilitated the nuclear translocation of Nrf2, increased the binding activity between Nrf2 and the antioxidant response elements (AREs), and lowered the expression of IL-1β in the LPS-treated HUVECs. In the animal model, AZC significantly reduced the expression of iNOS in the lung tissue structure and the TNF-α level in the bronchoalveolar lavage fluid. These findings demonstrate that AZC possesses anti-inflammatory properties that regulate iNOS through the inhibition of both NF-κB expression and p-STAT-1. Consequently, AZC has potential as a future candidate for the development of new clinical substances for the treatment of pathological inflammation.

• International Journal of Stem Cells
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• 제16권3호
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• pp.269-280
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• 2023

Background and Objectives: The colonic epithelial layer is a complex structure consisting of multiple cell types that regulate various aspects of colonic physiology, yet the mechanisms underlying epithelial cell differentiation during development remain unclear. Organoids have emerged as a promising model for investigating organogenesis, but achieving organ-like cell configurations within colonic organoids is challenging. Here, we investigated the biological significance of peripheral neurons in the formation of colonic organoids. Methods and Results: Colonic organoids were co-cultured with human embryonic stem cell (hESC)-derived peripheral neurons, resulting in the morphological maturation of columnar epithelial cells, as well as the presence of enterochromaffin cells. Substance P released from immature peripheral neurons played a critical role in the development of colonic epithelial cells. These findings highlight the vital role of inter-organ interactions in organoid development and provide insights into colonic epithelial cell differentiation mechanisms. Conclusions: Our results suggest that the peripheral nervous system may have a significant role in the development of colonic epithelial cells, which could have important implications for future studies of organogenesis and disease modeling.

• International Journal of Computer Science & Network Security
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• 제23권12호
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• pp.187-193
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• 2023

Large software systems are being produced with a noticeably higher level of quality with component-based software engineering (CBSE), which places a strong emphasis on breaking down engineered systems into logical or functional components with clearly defined interfaces for inter-component communication. The component-based software engineering is applicable for the commercial products of open-source software. Software metrics play a major role in application development which improves the quantitative measurement of analyzing, scheduling, and reiterating the software module. This methodology will provide an improved result in the process, of better quality and higher usage of software development. The major concern is about the software complexity which is focused on the development and deployment of software. Software metrics will provide an accurate result of software quality, risk, reliability, functionality, and reusability of the component. The proposed metrics are used to assess many aspects of the process, including efficiency, reusability, product interaction, and process complexity. The details description of the various software quality metrics that may be found in the literature on software engineering. In this study, it is explored the advantages and disadvantages of the various software metrics. The topic of component-based software engineering is discussed in this paper along with metrics for software quality, object-oriented metrics, and improved performance.

• 산업융합연구
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• 제22권3호
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• pp.27-37
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• 2024

본 연구의 목적은 유도 참여자의 커뮤니티 특성이 가치, 태도, 행동(VAB) 및 지속참여의도에 미치는 영향을 분석하는 것이다. 연구대상 표집은 편의표본추출법(n=192)을 사용하였으며, SPSS 26.0과 AMOS 26.0을 사용하여 확인적 요인분석, 상관관계 분석, 구조방정식 모델링을 실시하였다. 본 연구의 결과는 다음과 같다. 1) 유도 참여자의 커뮤니티 속성 중 평판, 즐거움, 상호작용, 사회적 연결감은 유의한 영향을 미쳤다. 2) 가치-태도-행동(VAB)은 위계적으로 유의미한 영향을 미치는 것으로 나타났다. 3) 행동 의도는 지속 의도에 유의미한 영향을 미치는 것으로 나타났다. 이를 통해 유도 커뮤니티는 참여자의 유도참여를 높이기 위해 긍정적인 가치를 창출할 수 있는 참여자 중심의 조직문화를 구축할 필요가 있다.