• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.5
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• pp.1036-1057
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• 2013

Wireless body area network (WBAN) is a promising candidate for future health monitoring system. Nevertheless, the path to mature solutions is still facing a lot of challenges that need to be overcome. Energy efficient scheduling is one of these challenges given the scarcity of available energy of biosensors and the lack of portability. Therefore, researchers from academia, industry and health sectors are working together to realize practical solutions for these challenges. The main difficulty in WBAN is the uncertainty in the state of the monitored system. Intelligent learning approaches such as a Markov Decision Process (MDP) were proposed to tackle this issue. A Markov Decision Process (MDP) is a form of Markov Chain in which the transition matrix depends on the action taken by the decision maker (agent) at each time step. The agent receives a reward, which depends on the action and the state. The goal is to find a function, called a policy, which specifies which action to take in each state, so as to maximize some utility functions (e.g., the mean or expected discounted sum) of the sequence of rewards. A partially Observable Markov Decision Processes (POMDP) is a generalization of Markov decision processes that allows for the incomplete information regarding the state of the system. In this case, the state is not visible to the agent. This has many applications in operations research and artificial intelligence. Due to incomplete knowledge of the system, this uncertainty makes formulating and solving POMDP models mathematically complex and computationally expensive. Limited progress has been made in terms of applying POMPD to real applications. In this paper, we surveyed the existing methods and algorithms for solving POMDP in the general domain and in particular in Wireless body area network (WBAN). In addition, the papers discussed recent real implementation of POMDP on practical problems of WBAN. We believe that this work will provide valuable insights for the newcomers who would like to pursue related research in the domain of WBAN.

• Journal of The Korean Association of Information Education
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• v.17 no.2
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• pp.225-232
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• 2013

The smart education is performed in the education field, but the contents related to the subject class performed in the various smart devices are insufficient and it is necessary to continue training teacher and learner for the app development education. Therefore this study developed and applied the contents production education program of the game type web app around elementary science 6 grade 1 term utilizing Storyline authoring tools, similar to PowerPoint and be executable in the various devices. After educating students, we investigate the convenience of the use of Storyline, satisfaction level of learning contents work activity, and the continued availability, and etc,. They are interested in the activity of the smart educational contents development and they wished to participate in the continued app development education and activity in spite of it make difficulty for using English menu.

• Journal of Environmental Health Sciences
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• v.43 no.4
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• pp.307-313
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• 2017

Objectives: Chemicals derived from various environment media contaminates food across the food supply chain. In Korea, levels of contaminants in food have been sporadically measured by monitoring programs of different government agencies. There is difficulty with data compilation and integrated analysis across media. Therefore, the aim of this study was to propose an overall integrated database and analytical platform design for the 'ECO-FOOD NET (Environmental COntaminant reduction platform for FOOD through an interagency collaboration NETwork)', a tool to support the reduction of environmental contaminants in food. Methods: We developed a new data structure and standardized protocols for the compilation of integrated data. In addition, we conducted subject-oriented logical and physical relational database modeling and created the architecture design of the platform. Results: We established a standardized code system related to exposure media and route, analysis method and food matrix. In addition, we designed the seven software modules of 'About the System', 'Introduction to Interagency Work', 'Media-Chemicals Profiles', 'Method Bank', 'Monitoring Data Base', 'Integrated Media Analysis', and 'Risk-Benefit Analysis'. Conclusions: This study will contribute to decision-making as a tool for executing risk management, such as sustainable reduction policies of contaminants in food.

• 한국공간정보시스템학회:학술대회논문집
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• 2007.06a
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• pp.246-251
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• 2007

The purpose of this study is to develop a grid based model for calculating the critical nonpoint source (NPS) pollution load (BOD, TN, TP) in Nak-dong area in South Korea. In the last two decades, NPS pollution has become a topic for research that resulted in the development of numerous modeling techniques. Watershed researchers need to be able to emphasis on the characterization of water quality, including NPS pollution loads estimates. Geographic Information System (GIS) has been designed for the assessment of NPS pollution in a watershed. It uses different data such as DEM, precipitation, stream network, discharge, and land use data sets and utilizes a grid representation of a watershed for the approximation of average annual pollution loads and concentrations. The difficulty in traditional NPS modeling is the problem of identifying sources and quantifying the loads. This research is intended to investigate the correlation of NPS pollution concentrations with land uses in a watershed by calculating Expected Mean Concentrations (EMC). This work was accomplished using a grid based modelling technique that encompasses three stages. The first step includes estimating runoff grid by means of the precipitation grid and runoff coefficient. The second step is deriving the gird based model for calculating NPS pollution loads. The last step is validating the gird based model with traditional pollution loads calculation by applying statistical t-test method. The results on real data, illustrate the merits of the grid based modelling approach. Therefore, this model investigates a method of estimating and simulating point loads along with the spatially distributed NPS pollution loads. The pollutant concentration from local runoff is supposed to be directly related to land use in the region and is not considered to vary from event to event or within areas of similar land uses. By consideration of this point, it is anticipated that a single mean estimated pollutant concentration is assigned to all land uses rather than taking into account unique concentrations for different soil types, crops, and so on.

• Journal of Information Technology Applications and Management
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• v.15 no.3
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• pp.195-208
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• 2008

In an emergency management case, evaluating the economic value of information technology investments is a challenging problem due to the effects of decision making, uncertainty of disasters, and difficulty of measurements. Risk assessment and recovery process, one of the major functions in emergency management, consists of (1) measurement of damages or losses, (2) recovery planning, (3) reporting and approving budgets, (4) auctioning off recovery projects to constructors, and (5) construction for the recovery. Specifically and of our interest, measurement of damages or losses is often a costly and time-consuming process because the wide range of field surveys should be performed by a limited pool of trained agents. Managers, therefore, have to balance accuracy of the field survey against the total time to complete the survey. Using information technologies to support field survey and reporting has great potential to reduce errors and lowers the cost of the process. However, existing cost benefit analysis framework may be problematic to evaluate and justify the IT investment because the cost benefit analysis often include the long-run benefit of IT that is difficult to quantify and overlook the impact of managerial control upon the investment outcomes. Therefore, we present an alternative cost-centric control model that conservatively quantifies all cost savings to replace benefits in cost benefit analysis and incorporate the managerial control. The model provides a framework to examine how managerial decision making and uncertainty of disaster affect the economic value of IT investments. The current project in Emergency Agency in South Korea is introduced as a case to apply the cost-centric control model. Our work helps managers to better evaluate and justify IT-related investment alternatives in emergency management.

• Journal of the Korean earth science society
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• v.30 no.6
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• pp.692-698
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• 2009

Wavelet transform has been widely used in terms that it may overcome the shortcoming of conventional Fourier transform. Fourier transform has its difficulty to explain how the transformed domain, frequency, is related with time. Traditional semblance technique in Fourier transform was devised to compare two time series on the basis of their phase as a function of frequency. But this method is known not to work well for the non-stationary signal. In this study, we present two applications of the wavelet-based semblance method to geophysical data. Firstly, we show filtered geomagnetic signal remained with components of high correlation to each observatory. Secondly, highly correlated residual signal of gravity and magnetic survey data, which are also filtered by this semblance method, is present.

• Journal of the Korea Convergence Society
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• v.9 no.12
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• pp.75-80
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• 2018

This study was conducted to provide basic data on the dental hygienists Happiness Index and identify factors influencing dental hygienists A self-administered questionnaire survey was conducted dental hygienists in Jeollabuk-do(Jeonju, Iksan, Gunsan) from October to November 2017. Data were analyzed using t-test, ANOVA and multiple regression. As the result of study, Happiness Index of socioeconomic level has increased when the more work career, and more monthly wage, and better interpersonal relationship. Happiness Index of psychological well-being has increased when younger group and more monthly wage, and better interpersonal relationship. Therefore, in order to increase the happiness index of dental hygienists, economic compensation such as incentives and if the education of the communication method of the cases where the most difficulty case of the communication situation in the human relationship is confirmed is preceded, the quality of the medical service provided to the patient due to the happy working life will be improved.

• International Journal of Computer Science & Network Security
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• v.21 no.5
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• pp.243-255
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• 2021

This study aimed to identify the effectiveness of the use of distance-evaluation tools and methods among students with learning difficulties from the teachers' point of view, to achieve this goal. A scale was built, and the psychometric characteristics were validated. It consisted, in its final form, of 17 items distributed on four axes, in addition to three open questions. It was applied to a random sample of (149) teachers of students with learning difficulties in Makkah Region. The results showed that teachers' keenness to encourage students with learning difficulties, so that they would not feel frustrated with the distance learning process. It was also evident that teachers did not use achievement portfolios in the evaluation process. In connection with the appropriate evaluation methods, the majority indicated the use of work sheets and visual evaluation methods that rely on audio and visual skills, such as presenting videos, pictures, audio and games, and applying short objective tests. Among the proposals to improve evaluation methods and tools: Individual evaluation, attention to individual treatment, obligating personal attendance of students to school, splitting the required tasks, and not increasing the skills required to be mastered. As for the obstacles that teachers face: Lack of time, difficulty in communicating with students with distance learning difficulties and problems related to the Internet such as interruption, weakness, or lack of availability.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.1
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• pp.37-53
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• 2021

The purpose of this study is to analyze the types of latent profiles depending on the job satisfaction of youth entrepreneurs in South Korea and examine the influence of related variables. Latent profile analysis (LPA) was conducted using data from the 12th year of the Youth Panel Study. Results of the study revealed that there were five latent profiles based on job satisfaction among young entrepreneurs: lowest job satisfaction, mid-low job satisfaction, middle job satisfaction, mid-high job satisfaction, and highest job satisfaction. By applying multinomial logistic analysis, the influencing factors for each latent profiles have been derived. Gender, marital status, subjective health, self-esteem, entrepreneurial motivation, difficulty in start-up, person-job fit, intrinsic or extrinsic job values, business scale, income, work hour, education or training, and labor insurance were significant predictors of youth entrepreneurs' job satisfaction. Based on these results, the article discusses practical implications that can enhance the job satisfaction of young entrepreneurs.

• Journal of Korea Entertainment Industry Association
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• v.14 no.8
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• pp.63-75
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• 2020

This paper researches the relationship between Youtube K-pop music video views and visual characteristics. K-pop music video, which is the subject of study has intrigued the world since 'Gangnam Style' became Youtube's most viewed video in 2012. This paper questions the existence of element that are related to music video views which is not externally visible and the availability of the discovering the specific element. Previous studies had difficulty in searching the inherent elements of the music video associated with views because they chose a research method that compares music videos based on one or two pieces of work and had a biased result. Therefore, this paper goals to divide nine music videos according to the number of views in three groups and analyze their visual characteristics to find out the differences between the groups and their each features. This paper will contribute to the development of music video field in Youtube market where the number of views is getting more important recently.