• Magazine of the Korea Concrete Institute
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• v.11 no.2
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• pp.241-249
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• 1999

To estimate the compressive strength of concrete more realistically, relative large number of data are necessary. However, it is very common in practice that only limited data are available. The purpose of the present paper is therefore to propose a realistic method to estimate the compressive strength of concrete with limited data in actual site. The Bayesian method of statistical analysis has been applied to the problem of the estimation of compressive strength of concrete. The mean compressive strength is considered as the random parameter and a prior distribution is selected to enable updating of the Bayesian distribution of compressive strength of concrete reflecting both existing data and sampling observations. The updating of the Bayesian distribution with increasing data is illustrated in numerical application. It is shown that by combining prior estimation with information from site observation, more precise estimation is possible with relatively small sampling. It is also seen that the contribution of the prior in determining the posterior distribution depends on its sharpness or flatness in relation to the sharpness or flatness of the likelihood function. The present paper allows more realistic determination of concrete strength in site with limited data.

• Journal of Korean society of Dental Hygiene
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• v.21 no.6
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• pp.751-761
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• 2021

Objectives: The purpose of this study was to examine the relationship between limited oral function and cardiovascular disease in adults over 40 years of age. Methods: Data from the Seventh Korean National Health and Nutrition Examination Survey (2016-2018) was used. In this study, 8,766 adults over the age of 40 years were included as study subjects. They completed a health survey which included current prevalence of hypertension, stroke, myocardial infarction, and angina pectoris, as well as information about blood tests, physical measurements, and oral examinations. Statistical analyses were carried out using complex sample cross-tabulation analysis, general linear model, and logistic regression analysis. Results: The study showed that limited oral function was experienced by patients with stroke (61.3%), myocardial infarction (49.1%), cardiovascular disease (38.5%), hypertension (38.1%), and angina (36.4%) (p<0.05). In patients with stroke, the risk of limited oral function was 2.393 times higher than in patients without stroke. Patients with hypertension were 1.233 times more at risk of speaking difficulty than those without hypertension. Conclusions: Limited oral function is associated with cardiovascular disease. To improve oral health, it is necessary to provide integrated, health-based oral care.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.5
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• pp.585-595
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• 2007

Representative impacts and effectiveness of surface meteorological observation data assimilation were examined in order to use wind resources estimation around southern coastal area of the Korean Peninsula. The data used in study are observational wind and temperature data at 5 and 41 sites of Regional Meteorological Offices and Automatical Weather Systems, respectively. Observation wind speed data tends to show small effective radius with limited area. Especially assimilation impacts of data observed at peninsula type sites like Yeosu play only around the inside of the peninsula. This limited effective radius for wind speed is caused by the strong correlation between topography and wind speed. And the efficient radius for surface air temperature is larger than that of wind. Data assimilation for observational air temperature is useful to increase the accuracy of wind energy estimation. However assimilation of wind data requires special care in its application due to high sensitivity of topographical complexity.

• Nuclear Engineering and Technology
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• v.54 no.9
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• pp.3205-3214
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• 2022

The aim of this study is to provide a clear and accessible method to obtain accurate true-stress strain data, and to extend the limited material data beyond the ultimate tensile strength (UTS) for AISI 304L. AISI 304L is used for the outer construction for some types of nuclear transport packages, due to its post-yield ductility and high failure strain. Material data for AISI 304L beyond UTS is limited throughout literature. 3D digital image correlation (DIC) was used during a series of uniaxial tensile experiments. Direct method extracted data such as true strain and instantaneous cross-sectional area throughout testing such that the true stress-strain response of the material up to failure could be created. Post processing of the DIC data has a considerable effect on the accuracy of the true stress-strain data produced. Influence of subset size and smoothing of data was investigated by using finite element analysis to inverse model the force displacement response in order to determine the true stress strain curve. The FE force displacement response was iteratively adapted, using subset size and smoothing of the DIC data. Results were validated by matching the force displacement response for the FE model and the experimental force displacement curve.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.4
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• pp.1-10
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• 2010

This present paper's goal is to show a virtual human agent's movement-data loci based on realistically limited perception data is human-like. To determine human-likeness of the movement-data loci, we consider interactions between two parameters: Realistically Limited Perception (RLP) data and Incremental Movement-Path data Generation (IMPG). That is to consider how the former (i.e., RLP), one of the simulated parameters of human thought or its elements dictates the latter (i.e., IMPG), one of the simulated parameters of human movement behavior. Mapping DB is a prerequisite for navigation in an agent system because it functions as an interface between perception and movement behavior. Although Hill et al. studied mapping DB methodology based on RLP, their research dealt only with a rendering camera's view point data. The agent system in this present paper was integrated with the Hill's mapping DB module and then the two parameters' interaction was considered on a military reconnaissance mission with unexpected enemy emergence. Movement loci that were generated by the agent and subjects were compared with each other. The agent system in this present research verifies that it can be a functional test bed for producing human-like movement-data loci although the human-likeness of agent is the result of a pilot test, determined by two parameters (RLP and IMPG) and only 30 subjects.

• International Journal of Highway Engineering
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• v.16 no.5
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• pp.67-72
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• 2014

PURPOSES : This study focuses on conducting pavement rehabilitation for more deteriorated roads given a limited government budget. METHODS : Therefore, we apply a optimization programming model of the permutation algorithm used for rehabilitating more deteriorated pavement areas, which is subjected to the limited budget. RESULTS : The permutation algorithm was evaluated in terms of determining the maximized rehabilitation of deteriorated pavement areas, using the newly developed performance models such as fatigue cracking, rutting, international roughness index(IRI) through the surveying data from 2006 to 2012. When compared with a traditional model of the so-called worst-first sequence(WFS) method, the permutation algorithm worked better than the WFS method, resulting in covering more deteriorated pavement areas given the limited government budget. CONCLUSIONS : Through a case study, it could be concluded that the permutation algorithm provides more reliable results in terms of rehabilitating more deteriorated pavement areas given the limited budget.

• Journal of Biomedical Engineering Research
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• v.29 no.1
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• pp.46-51
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• 2008

We describe a backprojection filtering method for limited angle tomography. In order to reduce blur artifacts originated from the out-of-planes and control high-frequency noise, we employed two band-limited window functions, and which were realized by Hann filters in this study. Based on the experimentally measured data, the performance of the developed method is demonstrated by comparing with the conventional shift-and-add and filtered backprojection methods. Application of the developed method to the dental imaging has a potential to be used for the preoperative evaluation of the jaw for dental implants with much reduced patient dose instead of the conventional dental computed tomography.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.6
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• pp.592-598
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• 2000

The locality of data references at the distributed shared memory systems affects the performance significantly. Data allocation methods by considering the locality of data references can improve the performance of DSM systems. This paper evaluates the performance for the dynamic limited directory scheme which data allocation methods can apply very effectively. The information of the data allocation is used by the dynamic limited directory scheme to set the presence bit effectively. And the proper use of the presence bit improves the performance by reducing memory overhead and using directory pool efficiently. Simulations are conducted using three application programs which have various data sharing. The results show that the optimal data allocation method improves the performance up to 3.6 times in the proposed scheme.

• Korean Journal of Adult Nursing
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• v.22 no.3
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• pp.291-302
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• 2010

Purpose: This study was a secondary data analysis aimed at identifying the predictors of health-related quality of life (HRQoL) of the home-dwelling disabled person by using EQ-5D which is a standardized instrument used as a measure of health outcome. Methods: Data were drawn from the 3rd Korea National Health and Nutritional Examination Survey conducted by the Ministry of Health and Welfare (MOHW). Subjects were 1,021 home-dwelling disabled persons over 19 years of age. Data were analyzed by using descriptive statistics, t-test, Pearson's correlation, one-way ANOVA, Scheff$\acute{e}$ test, and Stepwise multiple regression. Results: HRQoL (Health Related Quality of Life) is differentiated within age, genders, educational level, employment status, economic status, types and grades of disability, health problems associated with limited mobility, and the limited duration of time. HRQoL is correlated with age, number of cohabiters, educational level, grades of disability, activities of daily living (ADL), and instrumental ADL (IADL). HRQoL is significantly associated with ADL, health problems in connection with limited mobility, employment status, types of disability, marital status, grades of disability, and the limited duration of time. These factors explained 63.7% of variance in HRQoL. Conclusion: HRQoL among the disabled is related to their characteristics, ADL, and IADL. For this reason, it is necessary to develop health programs to promote those variables required to improve HRQoL.

• Journal of Korea Society of Digital Industry and Information Management
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• v.12 no.3
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• pp.75-85
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• 2016

MANET is a network composed only mobile network having limited resources and has dynamic topology characteristics. Therefore, every mobile node acts as a route and delivers data by using multi-hop method. In particular, group communication such as multicast is desperately needed because of characteristics such as battery life of limited wireless bandwidth and mobile nodes. However, the multicast technique can have different efficient of data transmission according to configuring method of a virtual topology by the movement of the nodes and the performance of a multicast can be significantly degraded. In this paper, the region based security multicast technique is proposed in order to increase the efficiency of data transmission by maintaining an optimal path and enhance the security features in data transmission. The group management node that manages the state information of the member nodes after the whole network is separated to area for efficient management of multicast member nodes is used. Member node encrypts using member key for secure data transmission and the security features are strengthened by sending the data after encrypted using group key in group management node. The superiority of the proposed technique in this paper was confirmed through experiments.