• Journal of Institute of Control, Robotics and Systems
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• v.15 no.2
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• pp.139-147
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• 2009

When the visually impaired walks inside a building like corridor, a GPS cannot be useful for the walker in estimating his or her position unlike the case of outdoor space. This paper presents two novel methods to measure the walking distance using a low cost camera worn on the chest of the visually impaired. In the first method we analyze the periodic variation of image focusing values. Walking steps are counted by checking the period for the rough measure of the walking distance. The second method counts the step number by monitoring fixtures on the ceiling, which have a certain interval. Lamps on the ceiling appeared on the video are monitored in this paper. The T-S fuzzy theory is used to detect lamps, and the walking steps are estimated by the positional variation of the lamp due to the gait of the walker. The two methods are tested in real experiment, and the results are compared.

• Journal of information and communication convergence engineering
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• v.13 no.2
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• pp.74-80
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• 2015

In cognitive radios, spectrum sensing plays an important role in accurately detecting the presence or absence of a licensed user. However, the intervention of malicious users (MUs) degrades the performance of spectrum sensing. Such users manipulate the local results and send falsified data to the data fusion center; this process is called spectrum sensing data falsification (SSDF). Thus, MUs degrade the spectrum sensing performance and increase uncertainty issues. In this paper, we propose a method based on the Hausdorff distance and a similarity measure matrix to measure the difference between the normal user evidence and the malicious user evidence. In addition, we use the Dempster-Shafer theory to combine the sets of evidence from each normal user evidence. We compare the proposed method with the k-means and Jaccard distance methods for malicious user detection. Simulation results show that the proposed method is effective against an SSDF attack.

• Research in Community and Public Health Nursing
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• v.21 no.2
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• pp.156-168
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• 2010

Purpose: The purpose of this study was to construct a questionnaire to assess male workers' sobriety behavior based on Ajzen's Theory of Planned Behavior (TPB). Methods: A primary questionnaire with 56 questions was constructed based on literature review and structured interview with male workers. The Content Validity Index (CVI) was evaluated by a group of experts, construct validity was tested by principle component analysis, and reliability was evaluated by Cronbach's ${\alpha}$ and the test-retest reliability test. Results: Fifty two questions showed higher than .8 of CVI. Four factors explained 78.71% of the total variance among items for sobriety intention and direct measure, and six factors explained 67.99% of the total variance among indirect measure items and those factors coincided with the variables of TPB in factor analysis. Cronbach's ${\alpha}$ of this questionnaire was .873 and the result of test-retest reliabilty test was relatively reliable. A total of 41 items with 7-point scale were constructed in the final version. Conclusion: This questionnaire was valid and reliable to measure sobriety behavior based on TPB in male workers. It can be useful to evaluate the result of a sobriety program for male workers.

• Journal of the Korean Society for Library and Information Science
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• v.6
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• pp.87-103
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• 1979

Information storage and retrieval is a part of general communication process. In the Shannon's information theory, information contained in a message is a measure of -uncertainty about information source and the amount of information is measured by entropy. Indexing is a process of reducing entropy of information source since document collection is divided into many smaller groups according to the subjects documents deal with. Significant concepts contained in every document are mapped into the set of all sets of index terms. Thus index itself is formed by paired sets of index terms and documents. Without indexing the entropy of document collection consisting of N documents is $log_2\;N$, whereas the average entropy of smaller groups $(W_1,\;W_2,...W_m)$ is as small $(as\;(\sum\limits^m_{i=1}\;H(W_i))/m$. Retrieval efficiency is a measure of information system's performance, which is largely affected by goodness of index. If all and only documents evaluated relevant to user's query can be retrieved, the information system is said $100\%$ efficient. Document file W may be potentially classified into two sets of relevant documents and non-relevant documents to a specific query. After retrieval, the document file W' is reclassified into four sets of relevant-retrieved, relevant-not retrieved, non-relevant-retrieved and non-relevant-not retrieved. It is shown in the paper that the difference in two entropies of document file Wand document file W' is a proper measure of retrieval efficiency.

• Journal of the Korean Society of Safety
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• v.21 no.2 s.74
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• pp.22-28
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• 2006

This paper presents assessment of possibility on the human risk for the electromagnetic field of unbalanced two coupled three-phase transmission line using fuzzy theory. Three phase load flow program was developed which employed a Newton-Raphson method as a tool to analyze system unbalanced. This research presents a method of handling two coupled three phase transmission system unbalance analysis and unbalanced power demand as a function of voltages. As the results of case study, in case of 345[kV] T/L, the electric field intensity was 10.9540[kV/m], magnetic field intensity was 0.2567[G] in severest case. The results showed that the membership of a proposition fuzzy '10.9540 [kV/m] is hazardous' is 0.6349. As the analytic results using the fuzzy qualifier term, the membership in case of very false is 0.1379 and fairly false is 0.6124, respectively. In assessment of fuzzy measure possibility for the electromagnetic field, this paper used probability of fuzzy arid measure of fuzziness technique.

• Journal of Information Science Theory and Practice
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• v.4 no.4
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• pp.64-74
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• 2016

In this paper we define a two parametric new generalized useful average code-word length $L_{\alpha}^{\beta}$(P;U) and its relationship with two parametric new generalized useful information measure $H_{\alpha}^{\beta}$(P;U) has been discussed. The lower and upper bound of $L_{\alpha}^{\beta}$(P;U), in terms of $H_{\alpha}^{\beta}$(P;U) are derived for a discrete noiseless channel. The measures defined in this communication are not only new but some well known measures are the particular cases of our proposed measures that already exist in the literature of useful information theory. The noiseless coding theorems for discrete channel proved in this paper are verified by considering Huffman and Shannon-Fano coding schemes on taking empirical data. Also we study the monotonic behavior of $H_{\alpha}^{\beta}$(P;U) with respect to parameters ${\alpha}$ and ${\beta}$. The important properties of $H_{{\alpha}}^{{\beta}}$(P;U) have also been studied.

• Ocean and Polar Research
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• v.29 no.1
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• pp.69-80
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• 2007

This paper attempts to measure the environmental value of the Nakdong-river estuary, which is ecologically important but confronted with the threat of development. Especially, in order to elicit the environmental values of its four attributes, contingent valuation method(CVM) based on multi-attribute utility theory is applied and the CVM survey was rigorously designed to comply with the guidelines for best-practiced CVM studies. We surveyed a randomly selected sample of 400 and 350 households in Busan and six large cities(Seoul, Incheon, Daegu, Daejeon, Gwangju, and Ulsan), respectively and asked respondents questions in person-to-person interviews about how they would willing to pay for the estuary conservation and management program. Respondents overall accepted the contingent market and were willing to contribute a significant amount(2,457 won in Busan and 3,560 won in six large cities), on average, per household per year, which implies that there exists a large difference between the two. The aggregate values of the Nakdong-river estuary in Busan and six large cities amount to 2.92 and 22.32 billion won, respectively, per year. In addition, expanding the values to Korea produces 51.34 billion won per year. The quantitative values can be utilized in planning and decision-making about development versus conservation of the estuary.

• Journal of Korean Association for Spatial Structures
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• v.17 no.2
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• pp.53-62
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• 2017

This study aims to establish a seismic resistance performance evaluation method that makes sure to secure the seismic resistance performance of the existing mid-low story reinforced concrete structures. This study focuses on the development of the seismic resistance performance evaluation method for the overall seismic resistance performance evaluation on the buildings by applying fuzzy theory. This seismic resistance performance evaluation method considers the mutual relations among the type of force, the type of member, the type of story, and the states of deterioration of the buildings. The total seismic resistance performance index from this method was calculated by the intensity weight of each evaluation item, fuzzy measure, fuzzy integration. Moreover, the evaluation methodology was established in this study to identify the performance level of the Immediate Occupancy, Life Safe, Collapse Prevention by applying the fuzzy theory.

• The Journal of Economics, Marketing and Management
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• v.8 no.2
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• pp.27-38
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• 2020

Purpose: Strategic management scholars have investigated the effects of corporate social responsibility (CSR) on firm financial performance, identifying various impacts of CSR activities showing conflicting results. Meanwhile, relatively less attention has been paid to the antecedents of CSR activities. According to upper echelons theory, organizational outcomes are predicted by characteristics of CEOs and top management team members. Corporate social responsibility is a type of organizational outcome influenced by such top leader characteristics and choices. Recognizing the importance of exploring new antecedents of CSR activities, I examine whether CEO humility affects CSR outcomes. Research design, data and methodology: The KEJI index was set as a dependent variable to measure CSR activities. Among the 200 sample companies registered in the KEJI database in 2014, 85 companies were finally selected and analyzed to measure CEO humility, as independent variable. I also examine the moderating effects of firm slack on the relationship between CEO humility and CSR activities. Results: There is a positive relationship between CEO humility and corporate social responsibility activities and this relationship is negatively moderated by firm slack. Conclusions: This paper contributes to understanding positive impacts of having humble CEOs on corporate social responsibility outcomes and recognizes the role of firm slack.

• Journal of Institute of Control, Robotics and Systems
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• v.5 no.6
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• pp.647-655
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• 1999

For linear time-varying systems described by the triple (A(t),B(t),C(t)) where A(t),B(t),C(t) are the system, the input, and the output matrices, respectively, we propose concepts for measures of modal and gross controllability /observability. We introduce a differential algebraic eigenbvalue theory for linear time-varying systems to calculate the PD-eigenvalues and left and right PD-eigenvectors of the system matrix A(t) which will be used to derive the concepts for the measures. The time-dependent angle between the left PD-eigenvectors of the system matrix A(t) and the columns of the input matrix B(t), and the magnitude of the each element of the input matrix B(t) are used to propose the modal controllability measure. Similarly, the time-dependent angle between the right PD-eigenvectors of the system matrix A(t) and the rows of the output matrix C(t) are used to propose the madal observability measure. Gross measure of controllability of a mode from all inputs and its gross measure of observability in all outputs for the linear time-varying systems are also proposed. Numerical examples are presented to illustrate the proposed concepts.