• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.3
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• pp.1533-1556
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• 2017

The concept of trust in vehicular ad hoc networks (VANETs) is usually utilized to assess the trustworthiness of the received data as well as that of the sending entities. The quality of safety applications in VANETs largely depends on the trustworthiness of exchanged data. In this paper, we propose a self-organized distributed trust computing framework (DTCF) for VANETs to compute the trustworthiness of each vehicle, in order to filter out malicious nodes and recognize fully trusted nodes. The proposed framework is solely based on the investigation of the direct experience among vehicles without using any recommendation system. A tier-based dissemination technique for data messages is used to filter out non authentic messages and corresponding events before even going farther away from the source of the event. Extensive simulations are conducted using Omnet++/Sumo in order to investigate the efficiency of our framework and the consistency of the computed trust metrics in both urban and highway environments. Despite the high dynamics in such networks, our proposed DTCF is capable of detecting more than 85% of fully trusted vehicles, and filtering out virtually all malicious entities. The resulting average delay to detect malicious vehicles and fraudulent data is showed to be less than 1 second, and the computed trust metrics are shown to be highly consistent throughout the network.

• Journal of muscle and joint health
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• v.23 no.3
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• pp.152-158
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• 2016

Purpose:The purpose of this study was to examine the degree of joint pain, limitation of daily activities, and frequency of outpatient visits. Methods: This secondary analysis study used the data from the fifth Korean National Health and Nutrition Examination Survey (KNHNES). The data about general characteristics, prevalence and treatment of osteoarthritis, limitation of activities of daily living (ADL) and frequency of outpatient visits and hospitalization in 424 osteoarthritis patients over 50 years old were derived from the database. Data were analyzed with complex samples in SPSS ver. 20.0. Results: Among people with knee joint pain, 79.3% reported they had more than 4 out of 10 points of the degree of pain. Meanwhile, 97.3% of people with hip joint pain reported that they had more than 4 out of 10 points of the degree of pain. People reporting 10 out of 10 point of pain were 21.4% of those with knee joint pain and 25% of those with hip joint pain. The mean of the degree of knee joint pain was 6.35, and the mean of the degree of hip joint pain was 6.89 out of 10 points. About 50% of people with osteoarthritis visited an outpatient clinic within the last 2 weeks, and 27% had limitation of ADL. Conclusion: It is necessary to develop an integrated intervention program to improve quality of life in patients with osteoarthritis.

• Research in Community and Public Health Nursing
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• v.24 no.1
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• pp.11-19
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• 2013

Purpose: This study was carried out to investigate relations among daily livingabilities, self-efficacy, and Yangsaegn behavior, and influencing factors on Yangsaeng behavior among elderly men. Methods: Data were collected from 497 male elders in the D metropolitan city. Research tools included ADL, IADL, and the scale for self-efficacy and Yangsaeng behavior. The data were analyzed using frequency analysis, average and standard deviation, t-test, One-way ANOVA, Pearson's correlation coefficients, and multiple regression analysis with the SPSS/WIN 19.0 program. Results: The subjects' ADL score was 2.86, their IADL score of subjects 2.66 out of 3, and their self-efficacy score was 2.68 out of 4, and their Yangsaeng behavior score 3.46 out of 5. There were significant differences in Yangsaeng behavior among the subjects due to age, education level, monthly income, marital status, family structure, religion, health status, andperiodic health examination. There were significant positive correlations among ADL, IADL, self-efficacy, and Yangsaeng behavior. According to the research, influencing factors on Yangseng behavior in elderly men included self-efficacy, health status, ADL, education level, IADL, and family structure. Conclusion: Findings from this study can be used as basic data to develop Yangsaeng behavior programs for elderly men.

• Korean Journal of Community Nutrition
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• v.14 no.6
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• pp.789-797
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• 2009

In order to investigate the effects of frequent eating-out and breakfast skipping of working men on body mass index and nutrients intake status, working male adults aged 20 or over were selected (n = 1883) from the data of 2001 Korea national health and nutrition survey. The subjects were divided into 4 groups according to the eating-out frequency(high: once or more daily, low: less than once daily) and breakfast eating or not. Four groups were high eating-out with breakfast eating (n = 609), high eating-out with breakfast skipping (n = 192), low eating-out with breakfast eating (n = 877), and low eating-out with breakfast skipping (n = 205). High eating-out group showed higher body mass index (BMI) than low eating-out group, but the difference of BMI was disappeared when adjusted with age, residence region and family income. However high eating-out group in case of breakfast eating, compared with the low eating-out, showed higher intakes or densities of energy, fat, fat-energy% and higher ratio of energy-fat overintake, and also showed higher mean nutritional adequacy ratio and lower ratio of nutrients intake deficiency. Calcium, iron, vitamin A and C intakes were not affected by eating-out frequency, but were lowered by breakfast skipping. Breakfast skipping also decreased intake frequency of unprocessed cereals and increased those of ramyon and carbonated and alcoholic beverages. From the results frequent eating-out with breakfast eating caused increased intakes of energy and fat, but did not cause BMI increase. Breakfast skipping, but not eating-out, had negative influences on mineral and vitamin intakes. Accordingly good eating-out as well as breakfast eating should be exceedingly emphasized at nutrition education for the working males.

• Journal of Korean Society of Transportation
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• v.17 no.3
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• pp.97-116
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• 1999

The growing demand for the real time traffic information is bringing about the category and number of traffic collection mechanism in the era of ITS. There are, however, two problems in making data into information using various traffic data. First, the information making process of making data into the representative information, for each traffic collection mechanism, for the specified analysis periods is required. Second, the integration process of fusing each representative information into "the information" for each link out of each source is also required. That is, both data reduction and/or data to information process and information fusion are required. This article is focusing on the development of information fusing algorithm based on voting technique, fuzzy regression, and, Bayesian pooling technique for estimating the dynamic link travel time of networks. The proposed algorithm has been validated using the field experiment data out of GPS probes and detectors over the roadways and the estimated link travel time from the algorithm is proved to be more useful than the mere arithmetic mean from each traffic source.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.585-588
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• 2008

KICT has been carried out inventory research on the cut slopes of national roads. Inventory research results are basic data using cut slope management system. Inventory data are classified by general status, cut slope characteristics and inspector opinion. Inventory data are utilized to figure out dangerous slopes and decide survey ranking of detailed safety diagnostication. This paper drew the distribution area of dangerous cut slopes using inventory data in Chungcheongdo, and verified efficiency on distribution area of dangerous cut slopes by comparing occurrence frequency of real collapsed cut slopes.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.2
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• pp.315-326
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• 2001

This study is to suggest data for setting school uniform size with the size satisfaction degree through finding out the physical body change and uniform size problems following an increase in age during middle school girl days. For this purpose, by analyzing the physical body size data of 13~15 age of girls among $\ulcorner$human body size data of the youth for product design$\lrcorner$publicized under sponsorship of National Technology Quality Institute in 1999 the physical body size change by part following an increase in age during middle school girl days was found out and the most frequent physical body size by grade was suggested. Questionnaire about uniform production status and product size at the object of uniform makers were measured directly, a school uniform wearing status and size satisfaction degree by part were at the abject of middle school girls were examined by means of questionnaire and unsatisfactory factors in uniform size were found out. Based on collected data the most optimum product size in each part by item were suggested. The method of suggesting the most optimum size suitability by item was decided based on the result of survey into corresponding title and product size by maker and that of survey into the size satisfaction degree of middle school girls by maker, and the product size of maker showing the highest size satisfaction degree was selected as the most optimum product size.

• Journal of the Korean Data and Information Science Society
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• v.6 no.1
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• pp.105-110
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• 1995

In this paper, we shall convey preservation of some partial orderings and closures of some positive ageing classes under k-out-of-n systems of like components. That is, if the life time of a component A is larger than that of a component B in any of the NBU, DMRL, NBUE, HNBUE, NBUFR and NBUFRA orderings, then a k-out-of-n system formed by i.i.d.. components of type A has larger life time, in that ordering, than that of a similar system consisting of n i.i.d. components type of B. And using these partial orderings, closures of positive aging classes(NBU, DMRL, NBUE, HNBUE, NBUFR and NBUFRA) under the coherent system like components.

• Asian Journal of Business Environment
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• v.12 no.4
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• pp.13-24
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• 2022

Purpose: Motivated by an expedited growth and distribution of Online Food-Delivery (OFD) services, especially during the recent Covid-19 pandemic, this research aims to explore 1) how consumers' sustainability considerations are associated with satisfaction with the services via opt-out cutlery options and 2) the role of the pandemic in the relationships between sustainability considerations, attitudes toward opt-out cutlery options, and satisfaction with the OFD services. Data and Methodology: An analysis of survey data using 434 consumers in the United States recruited from Amazon M-Turk was conducted using structural equation modeling. Results: Findings suggest that consumers' environmental, health, and ethical considerations are positively related to their attitudes toward opt-out cutlery options. Furthermore, attitudes toward opt-out cutlery options are positively related to satisfaction with the OFD services only when they feel connected with the environment, driven by perceived threats of an infectious disease (i.e. Covid-19). Conclusion: The study findings provide new insights to managers in the OFD service industry on how to promote sustainable consumption during the pandemic.

• Journal of the Korean Solar Energy Society
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• v.31 no.3
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• pp.89-94
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• 2011

In this study, we measured the wind data as new and renewable energy resources and carried out the evaluation of uncertainty about these data with the authentic standards. These data collected at the 20 locations in korea. We carried out the processing and evaluation about these data with standards as ISO, GUM, and IEC. Whereby these data become standards data and the credibility are gained. These data include some information as direction, humidity, pressure, temperature, and energy density. The annual average of wind speed(in Hamo) was measured as 9.5m/s, then the uncertainty was evaluated as ${\pm}0.88m/s$. We judge the credibility of data by expression of reliability quantitatively. In additional, the standards data is able to approach anywhere and it will be used to support of related research and industry.