• Title/Summary/Keyword: Age-diffusion model

Search Result 55, Processing Time 0.021 seconds

The Study on User's Continuance Intention of Traceability System between Agricultural and Marine Products (식품 유형간 이력추적시스템의 지속사용의도에 미치는 영향에 관한 연구)

  • Lee, Seung-Yook;Park, Hyeon-Suk
    • Journal of Distribution Science
    • /
    • v.14 no.4
    • /
    • pp.67-79
    • /
    • 2016
  • Purpose - Over recent years, we have concerned about safety and quality on food products because of delivery complexity. The dependence of foreign food products escalate supply of products. And there are often negligent accident of marine and agricultural products. Therefore, the complexity increases the importance of safety on food and information quality for consumers. In spite of the interest augmentation of various interested parties, there is decrease in reliability and effectiveness, if it would be established without the right directivity. For the study, we tried to examine the first considerations the point of - view in service environment and information quality with accepting and diffusing the Traceability System. Then, we tried to verify the relationships between the factors of TS and the determinants of behavior decision. Next, we made efforts to find the mutual relationship among distributors, producers, consumers and the other prerequisite factors from the point of view in service environment and information quality in order to operate effectively the information perspective and system. Research design, data, and methodology - For the purpose of this study, the samples of consumers were targeted to Traceability System, and 661 people have been investigated. Through theoretical discussion of previous research, nine hypotheses were established, the influence of Continuous User Intention in TS. In order to test the hypotheses, a survey had conducted for 661 consumers as opinion leaders in their 20s-60s as data, and structural equation modeling was used. The difference analysis between Agricultural and Marine Products in TS; SPSS 22.0 and AMOS 22.0 were used for statistical analysis. Results - The major findings from this study were as follow; all factors of information quality excluding completeness and a social-impact had effects on the ease of use; all factors excluding understand ability in information quality and a social-impact had effects on the usefulness; completeness and social-impact had effects on perceived value; the ease of use had effects on usefulness and perceived value; usefulness had effects on perceived value and the intention of continuous use. From the results of different analysis, the CPLT(Completeness) factor has positive effects on Easy of USE and PV(Perceived Value) strongly in agricultural products. On the other hand, Social Duty has positive effects on Easy of Use strongly in marine products. Conclusion - In the age of information overflowing, TS will be a burden for users if it places too much emphasis upon accessibility. To accept and diffuse TS safely, therefore, Information System should be settled first into initial market formation. In addition, if TS elements are considered in conjunction with information factors and user environment, the acceptance and diffusion of TS would make synergy effect, even better. That is, this study contributes to the acceptance and diffusion of Traceability System. Accordingly, information quality will be settled into initial market formation. Also, social-impact element will be considered in conjunction with information quality's factors, and it will make synergy effect.

A Moisture Diffusivity Model of Hardening Concrete (경화하는 콘크리트의 수분확산도 모형)

  • Jeong, Jin-Hoon
    • International Journal of Highway Engineering
    • /
    • v.7 no.1 s.23
    • /
    • pp.31-38
    • /
    • 2005
  • Concrete has higher vapor pressure than its surrounding ambient air immediately after placement. Moisture at concrete surface evaporates to the ambient air to adjust equilibrium of the vapor pressure between them. The moisture inside the concrete moves to the surface because the evaporation at the surface causes gradient of vapor pressure inside the concrete. Plastic cracking, degree of hydration, strength development, and others caused by velocity of the moisture movement significantly influences quality of concrete. In this paper, the moisture diffusivity of early-age concrete was back-calculated using governing equation of the moisture diffusion, and temperature and relative humidity of concrete measured in a laboratory. The moisture diffusivity of the concrete was modeled using the back-calculated moisture diffusivity. The relative humidity of the concrete calculated by finite element method (FEM) using the modeled moisture diffusivity as Input data coincided with the measured relative humidity well.

  • PDF

The Prediction of Durability Performance for Chloride Ingress in Fly Ash Concrete by Artificial Neural Network Algorithm (인공 신경망 알고리즘을 활용한 플라이애시 콘크리트의 염해 내구성능 예측)

  • Kwon, Seung-Jun;Yoon, Yong-Sik
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.26 no.5
    • /
    • pp.127-134
    • /
    • 2022
  • In this study, RCPTs (Rapid Chloride Penetration Test) were performed for fly ash concrete with curing age of 4 ~ 6 years. The concrete mixtures were prepared with 3 levels of water to binder ratio (0.37, 0.42, and 0.47) and 2 levels of substitution ratio of fly ash (0 and 30%), and the improved passed charges of chloride ion behavior were quantitatively analyzed. Additionally, the results were trained through the univariate time series models consisted of GRU (Gated Recurrent Unit) algorithm and those from the models were evaluated. As the result of the RCPT, fly ash concrete showed the reduced passed charges with period and an more improved resistance to chloride penetration than OPC concrete. At the final evaluation period (6 years), fly ash concrete showed 'Very low' grade in all W/B (water to binder) ratio, however OPC concrete showed 'Moderate' grade in the condition with the highest W/B ratio (0.47). The adopted algorithm of GRU for this study can analyze time series data and has the advantage like operation efficiency. The deep learning model with 4 hidden layers was designed, and it provided a reasonable prediction results of passed charge. The deep learning model from this study has a limitation of single consideration of a univariate time series characteristic, but it is in the developing process of providing various characteristics of concrete like strength and diffusion coefficient through additional studies.

Qualitative and Quantitative Magnetic Resonance Imaging Phenotypes May Predict CDKN2A/B Homozygous Deletion Status in Isocitrate Dehydrogenase-Mutant Astrocytomas: A Multicenter Study

  • Yae Won Park;Ki Sung Park;Ji Eun Park;Sung Soo Ahn;Inho Park;Ho Sung Kim;Jong Hee Chang;Seung-Koo Lee;Se Hoon Kim
    • Korean Journal of Radiology
    • /
    • v.24 no.2
    • /
    • pp.133-144
    • /
    • 2023
  • Objective: Cyclin-dependent kinase inhibitor (CDKN)2A/B homozygous deletion is a key molecular marker of isocitrate dehydrogenase (IDH)-mutant astrocytomas in the 2021 World Health Organization. We aimed to investigate whether qualitative and quantitative MRI parameters can predict CDKN2A/B homozygous deletion status in IDH-mutant astrocytomas. Materials and Methods: Preoperative MRI data of 88 patients (mean age ± standard deviation, 42.0 ± 11.9 years; 40 females and 48 males) with IDH-mutant astrocytomas (76 without and 12 with CDKN2A/B homozygous deletion) from two institutions were included. A qualitative imaging assessment was performed. Mean apparent diffusion coefficient (ADC), 5th percentile of ADC, mean normalized cerebral blood volume (nCBV), and 95th percentile of nCBV were assessed via automatic tumor segmentation. Logistic regression was performed to determine the factors associated with CDKN2A/B homozygous deletion in all 88 patients and a subgroup of 47 patients with histological grades 3 and 4. The discrimination performance of the logistic regression models was evaluated using the area under the receiver operating characteristic curve (AUC). Results: In multivariable analysis of all patients, infiltrative pattern (odds ratio [OR] = 4.25, p = 0.034), maximal diameter (OR = 1.07, p = 0.013), and 95th percentile of nCBV (OR = 1.34, p = 0.049) were independent predictors of CDKN2A/B homozygous deletion. The AUC, accuracy, sensitivity, and specificity of the corresponding model were 0.83 (95% confidence interval [CI], 0.72-0.91), 90.4%, 83.3%, and 75.0%, respectively. On multivariable analysis of the subgroup with histological grades 3 and 4, infiltrative pattern (OR = 10.39, p = 0.012) and 95th percentile of nCBV (OR = 1.24, p = 0.047) were independent predictors of CDKN2A/B homozygous deletion, with an AUC accuracy, sensitivity, and specificity of the corresponding model of 0.76 (95% CI, 0.60-0.88), 87.8%, 80.0%, and 58.1%, respectively. Conclusion: The presence of an infiltrative pattern, larger maximal diameter, and higher 95th percentile of the nCBV may be useful MRI biomarkers for CDKN2A/B homozygous deletion in IDH-mutant astrocytomas.

Determinants of Mobile Application Use: A Study Focused on the Correlation between Application Categories (모바일 앱 사용에 영향을 미치는 요인에 관한 연구: 앱 카테고리 간 상관관계를 중심으로)

  • Park, Sangkyu;Lee, Dongwon
    • Journal of Intelligence and Information Systems
    • /
    • v.22 no.4
    • /
    • pp.157-176
    • /
    • 2016
  • For a long time, mobile phone had a sole function of communication. Recently however, abrupt innovations in technology allowed extension of the sphere in mobile phone activities. Development of technology enabled realization of almost computer-like environment even on a very small device. Such advancement yielded several forms of new high-tech devices such as smartphone and tablet PC, which quickly proliferated. Simultaneously with the diffusion of the mobile devices, mobile applications for those devices also prospered and soon became deeply penetrated in consumers' daily lives. Numerous mobile applications have been released in app stores yielding trillions of cumulative downloads. However, a big majority of the applications are disregarded from consumers. Even after the applications are purchased, they do not survive long in consumers' mobile devices and are soon abandoned. Nevertheless, it is imperative for both app developers and app-store operators to understand consumer behaviors and to develop marketing strategies aiming to make sustainable business by first increasing sales of mobile applications and by also designing surviving strategy for applications. Therefore, this research analyzes consumers' mobile application usage behavior in a frame of substitution/supplementary of application categories and several explanatory variables. Considering that consumers of mobile devices use multiple apps simultaneously, this research adopts multivariate probit models to explain mobile application usage behavior and to derive correlation between categories of applications for observing substitution/supplementary of application use. The research adopts several explanatory variables including sociodemographic data, user experiences of purchased applications that reflect future purchasing behavior of paid applications as well as consumer attitudes toward marketing efforts, variables representing consumer attitudes toward rating of the app and those representing consumer attitudes toward app-store promotion efforts (i.e., top developer badge and editor's choice badge). Results of this study can be explained in hedonic and utilitarian framework. Consumers who use hedonic applications, such as those of game and entertainment-related, are of young age with low education level. However, consumers who are old and have received higher education level prefer utilitarian application category such as life, information etc. There are disputable arguments over whether the users of SNS are hedonic or utilitarian. In our results, consumers who are younger and those with higher education level prefer using SNS category applications, which is in a middle of utilitarian and hedonic results. Also, applications that are directly related to tangible assets, such as banking, stock and mobile shopping, are only negatively related to experience of purchasing of paid app, meaning that consumers who put weights on tangible assets do not prefer buying paid application. Regarding categories, most correlations among categories are significantly positive. This is because someone who spend more time on mobile devices tends to use more applications. Game and entertainment category shows significant and positive correlation; however, there exists significantly negative correlation between game and information, as well as game and e-commerce categories of applications. Meanwhile, categories of game and SNS as well as game and finance have shown no significant correlations. This result clearly shows that mobile application usage behavior is quite clearly distinguishable - that the purpose of using mobile devices are polarized into utilitarian and hedonic purpose. This research proves several arguments that can only be explained by second-hand real data, not by survey data, and offers behavioral explanations of mobile application usage in consumers' perspectives. This research also shows substitution/supplementary patterns of consumer application usage, which then explain consumers' mobile application usage behaviors. However, this research has limitations in some points. Classification of categories itself is disputable, for classification is diverged among several studies. Therefore, there is a possibility of change in results depending on the classification. Lastly, although the data are collected in an individual application level, we reduce its observation into an individual level. Further research will be done to resolve these limitations.