• 제목/요약/키워드: quantitative models

검색결과 1,006건 처리시간 0.025초

Glucosamine Inhibits Lipopolysaccharide-induced Inflammatory Responses in Human Periodontal Ligament Fibroblasts

  • Kim, Eun Dam;Park, Hyun-Jung;Baek, Jeong-Hwa
    • International Journal of Oral Biology
    • /
    • 제39권4호
    • /
    • pp.221-228
    • /
    • 2014
  • Glucosamine is commonly taken by the elderly without prescription as a nutritional supplement to attenuate the progression or symptoms of osteoarthritis. Previous studies demonstrated that glucosamine shows anti-inflammatory effects in tissues such as blood vessels and the heart. However, there have been few reports about the effects of glucosamine on oral inflammatory diseases. Therefore, in this study, the effects of glucosamine on lipopolysaccharide (LPS)-induced inflammatory responses were investigated using human periodontal ligament fibroblasts (HPDLFs). HPDLFs were incubated in the presence and absence of glucosamine (10 mM) for 24 h, followed by treatment with E. coli LPS (100 ng/ml) or vehicle. Quantitative RT-PCR and ELISA results showed that LPS exposure significantly increased the levels of IL-6 and IL-8 mRNA and protein, while the effect was significantly suppressed by glucosamine treatment. Glucosamine did not attenuate, but slightly increased, the LPS-induced activation of mitogen activated kinases (ERK, p38, JNK). However, it suppressed the LPS-induced increase in the DNA binding affinity and transcriptional activity of NF-${\kappa}B$. These results suggest that glucosamine exerts anti-inflammatory effects on HPDLFs exposed to LPS via inhibition of NF-${\kappa}B$ activity, necessitating further studies using animal periodontitis models.

핀테크 기반 주식투자 최적화 모델 구축 사례 연구 : 기관투자자 대상 (A Case Study on the Establishment of an Equity Investment Optimization Model based on FinTech: For Institutional Investors)

  • 김홍곤;김소담;김희웅
    • 지식경영연구
    • /
    • 제19권1호
    • /
    • pp.97-118
    • /
    • 2018
  • The finance-investment industry is currently focusing on research related to artificial intelligence and big data, moving beyond conventional theories of financial engineering. However, the case of equity optimization portfolio by using an artificial intelligence, big data, and its performance is rarely realized in practice. Thus, the purpose of this study is to propose process improvements in equity selection, information analysis, and portfolio composition, and lastly an improvement in portfolio returns, with the case of an equity optimization model based on quantitative research by an artificial intelligence. This paper is an empirical study of the portfolio based on an artificial intelligence technology of "D" asset management, which is the largest domestic active-quant-fiduciary management in accordance with the purpose of this paper. This study will apply artificial intelligence to finance, analyzing financial and demand-supply information and automating factor-selection and weight of equity through machine learning based on the artificial neural network. Also, the learning the process for the composition of portfolio optimization and its performance by applying genetic algorithms to models will be documented. This study posits a model that the asset management industry can achieve, with continuous and stable excess performance, low costs and high efficiency in the process of investment.

Re-conceptualization of Business Model for Marketing Nowadays: Theory and Implications

  • FIRMAN, Ahmad;PUTRA, Aditya Halim Perdana Kusuma;MUSTAPA, Zainuddin;ILYAS, Gunawan Bata;KARIM, Kasnaeny
    • The Journal of Asian Finance, Economics and Business
    • /
    • 제7권7호
    • /
    • pp.279-291
    • /
    • 2020
  • This study aims to develop the concept of innovation models with the marketing channel construct approach, marketing innovation, product segmentation, and customer insight; as well as improvements to the theory of resource-based combined with the method of service-dominant logic. This study approach is based on quantitative descriptive conducted with three stages of testing scenarios. The first test is the mapping of the innovation model construct through testing the validity and reliability with the moderation of customer orientation variables. The second scenario examines the relationship of influence between the independent variables on the dependent variable of 29 hypothetical analysis equation modeling. The unit of analysis was conducted on 497 SMEs involved in the food and beverage sectors, with the criteria being SMEs must have a rating of 4-5 points on the Go-Food applications software. The results shown that: 1) the construct used to develop an innovative model both directly and via moderation is positive and significant; 2) Through a complicated relationship that involves all components of the variable, it outlines a positive and significant effect except for the path of analysis (μ5). The theoretical and managerial implications state that the service-dominant logic approach and resource-based view theory have extreme reliability and interrelations.

의사결정나무 변수 선정 방법을 적용한 대축적 생물다양성 지도 구축 (Mapping Biodiversity throughoptimized selection of input variables in decision tree models)

  • 김도연;허준;김창재
    • 환경영향평가
    • /
    • 제20권5호
    • /
    • pp.663-673
    • /
    • 2011
  • In the face of accelerating biodiversity loss and its significance in our coexistence with nature, biodiversity is becoming more crucial in sustainable development perspective. To estimate biodiversity in the future which provides valuable information for decision making system especially in the national level, a quantitative approach must be studied forehand as a baseline of the present status. In this study, we developed a large-scale map of Plant Species Richness (PSR, typical indicator of biodiversity) for Young-dong and Pyung-chang provinces. Due to the accessibility of appropriate data and advance of modelling techniques, reduction of variables without deteriorating the predictive power is considered by applying Genetic algorithm. In addition, a number of Correctly Classified Instances (CCI) with 10-fold cross validation which indicates the predictive power, was carried out for evaluation. This study, as a fundamental baseline, will be beneficial in future land work as well as ecosystem restoration business or other relevant decision making agenda.

Sediment Fluxes in Shelf Seas Modelling and Monitoring

  • Prandel, David
    • Journal of the korean society of oceanography
    • /
    • 제37권3호
    • /
    • pp.144-153
    • /
    • 2002
  • This is a review paper, assessing progress reported in a Special Issue (Prandle and Lane, 2000) of Coastal Engineering focusing on simulation of SPM in the North Sea, against issues over a diverse range of shelf seas and their coastal margins. The broad objectives of reproducing the characteristics of sediment fluxes off an open coast and relating these to tidal and wave forcing were achieved. However, accurate computation of these fluxes remains sensitive to largely empirical coefficients used in determining erosion and deposition rates. Bed roughness strongly influences both these coefficients and the associated near-bed current magnitudes (including wave impact thereon). Bed roughness can change significantly over a tidal cycle and dramatically over seasons or in the course of a major event. Accurate simulation of sediment fluxes on a day-to-day basis is constrained by dependency on the initial distribution of mobile sediments. The latter depends on rates and locations of original sources and the time history of preceding events. Remote sensing via aircraft could provide data for assimilation into such models to circumvent these constraints. The approaches described here can be readily applied to other coastal regions to indicate the likely distributions and pathways of known sediment sources. However quantitative simulations will require an associated observational programme. A subsequent stage is to understand the evolving balance between the forecasted sediment movement - the resulting morphological adjustments and thence modifications to the prevailing tidal current and wave regimes.

Landsat영상과 현지조사에 의한 여름철 논과 산림의 기온저감효과 평가 (Assessment of the ATC Effect for Paddy Field and Forest Using Landsat Images and In-situ Measurement)

  • 박종화;나상일;김진수
    • 한국수자원학회:학술대회논문집
    • /
    • 한국수자원학회 2007년도 학술발표회 논문집
    • /
    • pp.1943-1947
    • /
    • 2007
  • The objective of this research was to find a direct and indirect method to estimate land surface temperature (LST) efficiently, using Landsat images and in-situ measurement. Agricultural fields including paddy fields have long been known to have multi-functions beneficial to the environment and ecology of the urban surrounding areas. Among these functions, the ambient temperature cooling (ATC) effect are widely acknowledged. However, quantitative and regional assessment of such effect has not had many investigations. Thermal remote sensing has been used over urban areas to assess ATC effect, to perform land cover classifications and as input for models of urban surface atmosphere exchange. Here, we review the use of thermal remote sensing in the study of paddy fields and urban climates, focusing primarily on the ATC effect. Landsat satellite images were used to determine the surface temperatures of different land cover types of a $441km^2$ study area in Cheongju, Korea. The results show that the ATC are a function of paddy area percentage in Landsat pixels. Pixels with higher paddy area percentage have more significant cooling effect.

  • PDF

LANDSAT영상을 이용한 여름철 청주지역의 토지피복과 지표면온도와의 관계 분석 (Analysis of the Relationship Between Land Cover and Land Surface Temperature at Cheongju Region Using Landsat Images in Summer Day)

  • 박종화;김진수;나상일
    • 한국농공학회논문집
    • /
    • 제48권5호
    • /
    • pp.39-48
    • /
    • 2006
  • The objective of this research was to find an indirect method to estimate land surface temperature (LST) efficiently, using Landsat images. Agricultural fields including paddy fields have long been known to have multi-functions beneficial to the environment and ecology of the urban surrounding areas. Among these functions, the ambient temperature cooling (ATC) effect is widely acknowledged. However, quantitative and regional assessment of such effect has not been performed. Thermal remote sensing has been used over urban areas to assess the ATC effect, Thermal Island Effect(TIE), and as input for models of urban surface atmosphere exchange. Here, we review the use of thermal remote sensing in the study of paddy fields and urban climates, focusing primarily on the ATC effect. Landsat satellite images were used to determine the surface temperatures of different land cover types of a $44km^{2}$ study area in Cheongiu, Korea. The results show that the ATC is a function of paddy area percentage in Landsat pixels. Landsat pixels with higher paddy area percentage have much more cooling effect. The use of satellite data may contribute to a globally consistent method for analysis of ATC effect.

문항반응이론을 이용한 컴포넌트 기반의 U-러닝 시스템 (The Component based U-Learning System using Item Response Theory)

  • 정화영
    • 인터넷정보학회논문지
    • /
    • 제8권6호
    • /
    • pp.127-133
    • /
    • 2007
  • u-러닝 환경은 수 없이 많은 단계를 거쳐 발전되어 왔으며, 현재에는 학습자의 학습 결과 분석과 양적인 사용, 질적인 평가 등을 통하여 정립되고 있다. 일반적으로 개선된 학습 효과와 학습자의 학습 결과분석을 위하여 대부분의 학습 시스템이 문항분석방법을 이용되고 있다. 그러나 오늘날 학습 시스템은 문항분석이론 대신에 문항반응이론을 사용하고 있다. 문항분석이론은 시험에 대한 각각의 가능한 응답에 대한 확률을 위해 명확한 모델을 제시한다. 따라서 본 연구에서는 문항반응이론을 이용한 경량 컴포넌트 기반의 u-러닝 시스템을 제시하고자 한다. u-러닝에 적용된 기기는 윈도우 모바일 5.0 환경의 PDA로 하였다.

  • PDF

Phrase positional effects on F0 peak timing in Tokyo Japanese

  • 조혜선
    • 말소리와 음성과학
    • /
    • 제3권3호
    • /
    • pp.69-75
    • /
    • 2011
  • This paper investigates phrase positional effects on the timing of F0 (pitch) peaks in Tokyo Japanese disyllabic words with varying accent type (HL or LH) and phrase position (final or non final). The F0 peak timing was normalized by the total word duration ('normalized H timing'). The normalized H timing was significantly affected by accent type and phrase position. The H timing was later in the LH accent type than in the HL accent type, and in non final positions than in final positions. In addition, to examine the validity of the quantitative results, different models of phrase position effects were compared by measuring H timing in two approaches: normalization versus relative distance measures. For the normalization measures, the H timing was measured as the time of the F0 peak divided by the total word duration or by the duration of the tone bearing syllable. For the relative distance measures, the H timing was measured as the distance in milliseconds from the end of the word or from the end of the associated syllable. The best model was the normalization by the total word duration, rather than by the duration of the tone bearing syllable. This means that phrase positional effects on the timing of F0 peaks in Japanese disyllabic words are best modeled in terms of proportion of the total word duration.

  • PDF

DEM 융합 기법을 이용한 다중영상스테레오 방법 (Multi-Image Stereo Method Using DEM Fusion Technique)

  • 임성민;우동민
    • 대한전기학회논문지:시스템및제어부문D
    • /
    • 제52권4호
    • /
    • pp.212-222
    • /
    • 2003
  • The ability to efficiently and robustly recover accurate 3D terrain models from sets of stereoscopic images is important to many civilian and military applications. A stereo matching has been an important tool for reconstructing three dimensional terrain. However, there exist many factors causing stereo matching error, such as occlusion, no feature or repetitive pattern in the correlation window, intensity variation, etc. Among them, occlusion can be only resolved by true multi-image stereo. In this paper, we present multi-image stereo method using DEM fusion as one of efficient and reliable true multi-image methods. Elevations generated by all pairs of images are combined by the fusion process which accepts an accurate elevation and rejects an outlier. We propose three fusion schemes: THD(Thresholding), BPS(Best Pair Selection) and MS(Median Selection). THD averages elevations after rejecting outliers by thresholding, while BPS selects the most reliable elevation. To determine the reliability of a elevation or detect the outlier, we employ the measure of self-consistency. The last scheme, MS, selects the median value of elevations. We test the effectiveness of the proposed methods with a quantitative analysis using simulated images. Experimental results indicate that all three fusion schemes showed much better improvement over the conventional binocular stereo in natural terrain of 29 Palms and urban site of Avenches.