• 대한기계학회논문집A
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• 제30권5호
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• pp.520-527
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• 2006

The design of major industrial facilities for the prevention of fatigue failure is customarily done by defining a set of transients and performing a calculation of cumulative usage factor. However, sometimes, the inherent conservatism or lack of details as well as unanticipated transients in old plant may cause maintenance problems. Even though several famous on-line monitoring and diagnosis systems have been developed world-widely, in this paper, a new system fur fatigue monitoring and life evaluation of crane is proposed to reduce customizing effort and purchasing cost. With regard to the system, at first, comprehensive operating transient data has been acquired at critical locations of crane. The real-time data were classified, by using adaptive resonance theory that is one of typical artificial neural network, into representative stress groups. Then the each classified stress pattern was mapped to calculated cumulative usage factor in accordance with ASME procedure. Thereby, promising results were obtained fur the crane and it is believed that the developed system can be applicable to other major facilities extensively.

• International Journal of Automotive Technology
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• 제7권1호
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• pp.43-49
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• 2006

In this paper, an index for the evaluation of a vehicle intake booming noise and intake sound quality were developed through a correlation analysis and a multiple factor regression analysis of objective measurement and subjective evaluation data. At first, an intake orifice noise was measured at the wide-open throttle test condition. And then, an acoustic transfer function between intake orifice noise and interior noise at the steady state condition was estimated. Simultaneously, subjective evaluation was carried out with a 10-scale score by 8 intake noise and vibration expert evaluators. Next, the correlation analysis between the psychoacoustic parameters derived from the measured data and the subjective evaluation was performed. The most critical factor was determined and the corresponding index for intake booming noise and sound quality are obtained from the multiple factor regression method. And, the optimal design of intake system was studied using the booming noise and the sound quality evaluation index for expectation performance of intake system. Conclusively, the optimal designing parameters of intake system from noise level and sound quality whose point of view were extracted by adapting comparative weighting between the booming noise and sound quality evaluation index, which optimized the process. These work could be represented guideline to system engineers, designers and test engineers about optimization procedure of system performance by considering both of noise level and sound quality.

• The Journal of Asian Finance, Economics and Business
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• 제8권3호
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• pp.619-628
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• 2021

Enterprise system (ES) reflects a significant IT commitment to achieve corporate goals and satisfy its thrust toward a sustainable competitive advantage. This research investigates the required ES architecture, the value of a well-planned ES, and the human factor capabilities that drive the effective implementation of ES from a management perception. This paper examined the critical factors shaping the business systems' performance, architecture readiness, experts' readiness, and enterprise systems planning. Based on an extensive literature review, the attributes of factors mentioned earlier were identified, classified and then statistically examined using the author's' proposed conceptual structural model. This study employs a quantitative research methodology, with a random sampling technique. This paper has used the data collected from 510 respondents working in service, engineering and health sectors in OMAN. The study model analysis utilized both exploratory and confirmatory factor analysis, followed by a structural equation modeling using SPSS 25 and EQS6.3 statistical tools. The results unveil a piece of remarkable and robust evidence suggesting that ES planning is the most significant aspect of influencing performance, followed by IT personnel, staff and consumers expertise, and architecture readiness.

• Journal of Ginseng Research
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• 제44권2호
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• pp.282-290
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• 2020

Background: Ginseng is a commonly used herbal medicine in treating various medical conditions. Chronic gut inflammation is a recognized factor for the development of colorectal cancer (CRC). In this project, Asian ginseng berry polysaccharide preparations were used to assess their effects on CRC and related immune regulation mechanisms. Methods: Ginseng berry polysaccharide extract (GBPE) and purified ginseng berry polysaccharide portion (GBPP) were used to evaluate their activities on human HCT-116 and HT-29 CRC cell proliferation. Interleukin-8 secretion analysis was performed on HT-29 cells. Naive CD4 cell isolation and T-helper cell differentiation were performed and determined using flow cytometry for Th1 and Treg in addition to cell cycle and apoptotic investigation. Results: GBPE and GBPP significantly inhibited interleukin-8 secretion and cancer cell proliferation, inhibited CD4⁺IFN-γ⁺ cell (Th1) differentiation, and decreased CD4⁺FoxP3⁺ cell (Treg) differentiation. Compared to the GBPE, GBPP showed more potent antiinflammatory activities on the malignant cells. This is consistent with the observation that GBPP can also inhibit Th1-cell differentiation better, suggesting that it has an important role in antiinflammation, whereas Treg cells hinder the body's immune response against malignancies. Supported by cell cycle and apoptosis data, GBPE and GBPP, at various degrees, remarkably enhanced the anticancer activities of 5-fluorouracil. Conclusion: Data from this project suggested that Asian ginseng berry potentially has clinical utility in managing enteric inflammation and suppressing CRC through immunomodulation mechanisms.

• BMB Reports
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• 제49권8호
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• pp.437-442
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• 2016

We aimed to study the role of protein L-isoaspartyl methyltransferase (PIMT) in neuronal differentiation using basic fibroblast growth factor (bFGF)-induced neuronal differentiation, characterized by cell-body shrinkage, long neurite outgrowth, and expression of neuronal differentiation markers light and medium neurofilaments (NF). The bFGF-mediated neuronal differentiation of PC12 cells was induced through activation of mitogen-activated protein kinase (MAPK) signaling molecules [MAPK kinase 1/2 (MEK1/2), extracellular signal-regulated kinase 1/2 (ERK1/2), and p90RSK], and phosphatidylinositide 3-kinase (PI3K)/Akt signaling molecules PI3Kp110β, PI3Kp110γ, Akt, and mTOR. Inhibitors (adenosine dialdehyde and S-adenosylhomocysteine) of protein methylation suppressed bFGF-mediated neuronal differentiation of PC12 cells. PIMT-eficiency caused by PIMT-specific siRNA inhibited neuronal differentiation of PC12 cells by suppressing phosphorylation of MEK1/2 and ERK1/2 in the MAPK signaling pathway and Akt and mTOR in the PI3K/Akt signaling pathway. Therefore, these results suggested that PIMT was critical for bFGF-mediated neuronal differentiation of PC12 cells and regulated the MAPK and Akt signaling pathways.

• Tuberculosis and Respiratory Diseases
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• 제80권3호
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• pp.304-310
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• 2017

Background: Chronic obstructive pulmonary disease (COPD), is a chronic inflammatory disorder. We evaluated whether white blood cell (WBC) count, is associated with the severity of COPD, independent of other inflammatory conditions, such as metabolic syndrome. Methods: The WBC counts were compared between 1227 COPD patients and 8679 non-COPD adults older than 40. The relationships between the WBC count, lung function, and symptoms score in COPD patients, were determined, using general linear regression analyses. Results: The WBC count was negatively associated with forced vital capacity (FVC, L), FVC (% predicted), forced expiry volume in one second ($FEV_1$, L), and $FEV_1$ (% predicted) in COPD patients. Additionally, the WBC count was independently associated with the quality of life measure, by EQ5D-index score. However, this relationship between WBC count, and disease severity, was not significant in current smokers, because of the confounding effect of smoking, on the WBC count. Conclusion: The WBC count is associated with current smoking status and COPD severity, and a risk factor for poor lung function, and quality of life, especially in non-currently smoking COPD patients. The WBC count can be used, as an easily measurable COPD biomarker.

• 지질공학
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• 제27권1호
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• pp.31-40
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• 2017

한계평형법에 의한 비탈면 안정성 해석은 활동면을 반복적인 해석 후 임계면을 설정하여 해석을 수행하고, 지반이 균질한 경우에만 적용이 가능하며, 안전율만 산정 할 수 있는 단점이 있다. 그러나 강도감소법을 적용한 해석에서는 수행자가 여러 가지 측면에 대해서 판단하고, 안전율을 산정 할 수 있는 장점 등이 있다. 본 연구에서는 동일한 크기의 비탈면을 대상으로 한계평형해석과 강도감소법을 활용하여 경사도 변화에 따른 두 해석법 간의 안전율 변화 양상과 점착력과 내부마찰각의 변화에 따른 안전율 변화 추이를 비교 분석하였다. 각각의 해석법에 따른 안정해석 분석 결과 지반내 응력, 변위와 변형률 등을 종합적으로 검토할 수 있는 강도감소법이 활용도가 높을 것으로 판단된다.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2003년도 추계학술대회 논문집
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• pp.1221-1222
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• 2003

본 연구는 Usability 중심의 웹사이트 평가를 위한 프레임워크 모델의 구축을 목표로 한다. 이를 위해 기존에 구축된 웹사이트 평가 방법론을 분석하여 평가 요소 별 중요도를 설정하였다. 비교 분석을 통해 나온 문제점들을 기초로 웹사이트평가를 위한 평가요인(Critical Factor)을 선정하여 새로운 프레임워크 모델 $C^3$ISP(Contents, Community, Commerce, Interface, Security, Performance)를 제시하였다. 향후 연구과제로는 프레임워크의 유용성을 분석하기 위한 Running Test를 실시한다.

• 터널과지하공간
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• 제18권6호
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• pp.447-456
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• 2008

노천광산에서 사면설계는 안정성과 경제성 측면에서 동시에 접근하여 결정해야 한다. 또한 일반 도로나 철도 연변의 사면과는 달리 대부분 지보나 보강없이 굴착해야 하기 때문에 사면각도가 가장 중요한 설계 변수이다. 본 연구에서는 인도네시아 파시르에 위치한 노천채광방식의 대규모 석탄광산 사면에 대하여 안정성 측면에서의 사면 각도 및 한계사면높이를 결정하였으며 이러한 설계가 가지고 있는 불확실성을 보완할 수 있는 계측 및 계측자료 해석을 수행하였다. 연구 결과, 사면각도(Overall Elope angle) $30^{\circ}$를 유지하는 경우 안전율 1.5를 확보하는 최대개발심도는 $353{\sim}438m$로 계산되었으나 강도정수에 대한 민감도분석결과를 고려할 때 사면높이는 300m를 초과하지 않는 것이 바람직하다. 또한 변위계측자료에 대한 역변위속도 분석 결과가 현장사면 사례와 잘 일치하여 이 방법을 통해 사면의 불안정성 및 파괴시기를 대략적으로 예측할 수 있을 것으로 판단된다.

• Journal of Welding and Joining
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• 제3권2호
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• pp.52-63
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• 1985

Fillet welded joints, specially in ship structure, are well known the critical part where stress concentrate or crack initiates and grows. This paper is concerned with the study of the behavior of fatigue crack growth t the root and toe of load carrying cruciform fillet welded joints under three points bending by the determination of stress intensity factor from the J-Integral, using the Finite Element Method. The stress intensity factor was investigated in accordance to the variation of the weld size (H/Tp). weld penetration (a/W) and plate thickness (2a'/Tp). As mixed mode is occurred on account of shearing force under the three points bending, Stern's reciprocal theory is applied to confirm which mode is the major one. The main results may be summarized as follows 1) The calculation formula of the stress intensity factor at the both of root and toe of the joint was obtained to estimate the stress intensity factor in the arbitrary case. 2) The change of stress field around crack tip gives much influence on each other at the roof and toe as H/Tp decreases. 3) Mode I is a major mode under the three points bending.