• Journal of Korean Institute of Industrial Engineers
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• v.30 no.1
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• pp.11-16
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• 2004

Oxygen is an essential element for human beings' physical and mental activities, and in particular, plays an important role in brain functions. The present study attempted to investigate the effects of supply of highly concentrated (30%) oxygen on human ability of visuospatial cognition, compared to air of normal oxygen concentration (21%). This study sampled eight male university students (the average age: 23.5) as subjects. An equipment that supplies 21% and 30% oxygen at a constant rate of 8L/min was developed. Two types of questionnaire containing 20 questions were developed to measure the ability of visuospatial cognition, and accuracy and reaction time were calculated from the result of task performance. The average accuracy was $50.63{\pm}8.63$ [%] and $62.50{\pm}9.64$[%] for 21%and 30% oxygen respectively, and a statistically significant difference was found in the accuracy between the two types of oxygen. The average reaction time was $6.60{\pm}O.77$ [sec] and $7.23{\pm}0.69$ [sec] for 21%and 30% oxygen respectively, and a statistically significant difference was not found in the reaction time. The results showed that there is no difference in the average reaction time but the average accuracy rises with the supply of highly concentrated (30%) oxygen, indicating that the supply of highly concentrated oxygen has a partially positive effect on the ability of visuospatial cognition.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.303-304
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• 2007

In this paper, we implement an automatic distance speech recognition system for voiced-enabled services. We first construct a baseline automatic speech recognition (ASR) system, where acoustic models are trained from speech utterances spoken by using a cross-talking microphone. In order to improve the performance of the baseline ASR using distance speech, the acoustic models are adapted to adjust the spectral characteristics of speech according to different microphones and the environmental mismatches between cross-talking and distance speech. Next we develop a voice activity detection algorithm for distance speech. We compare the performance of the base-line system and the developed ASR system on a task of PBW (Phonetically Balanced Word) 452. As a result it is shown that the developed ASR system provides the average word error rate (WER) reduction of 30.6 % compared to the baseline ASR system.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.9
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• pp.1492-1512
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• 2011

Due to multiple hops, mobility and time-varying channel, supporting delay sensitive real-time traffic in wireless local area network-based (WLAN) mesh networks is a challenging task. In particular for real-time traffic subject to medium access control (MAC) layer control overhead, such as preamble, carrier sense waiting time and the random backoff period, the performance of real-time flows will be degraded greatly. In order to support real-time traffic, an efficient adaptive packet scheduling (APS) scheme is proposed, which aims to improve the system performance by guaranteeing inter-class, intra-class service differentiation and adaptively adjusting the packet length. APS classifies incoming packets by the IEEE 802.11e access class and then queued into a suitable buffer queue. APS employs strict priority service discipline for resource allocation among different service classes to achieve inter-class fairness. By estimating the received signal to interference plus noise ratio (SINR) per bit and current link condition, APS is able to calculate the optimized packet length with bi-dimensional markov MAC model to improve system performance. To achieve the fairness of intra-class, APS also takes maximum tolerable packet delay, transmission requests, and average allocation transmission into consideration to allocate transmission opportunity to the corresponding traffic. Detailed simulation results and comparison with IEEE 802.11e enhanced distributed channel access (EDCA) scheme show that the proposed APS scheme is able to effectively provide inter-class and intra-class differentiate services and improve QoS for real-time traffic in terms of throughput, end-to-end delay, packet loss rate and fairness.

• Journal of IKEEE
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• v.23 no.1
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• pp.242-248
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• 2019

Fire flame and smoke detection algorithm studies are challenging task in computer vision due to the variety of shapes, rapid spread and colors. The performance of a typical sensor based fire detection system is largely limited by environmental factors (indoor and fire locations). To solve this problem, a deep learning method is applied. Because it extracts the feature of the object using several methods, so that if a similar shape exists in the frame, it can be detected as false postive. This study proposes a new algorithm to reduce false positives by using frame similarity before using deep learning to decrease the false detection rate. Experimental results show that the fire detection performance is maintained and the false positives are reduced by applying the proposed method. It is confirmed that the proposed method has excellent false detection performance.

• Journal of Intelligence and Information Systems
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• v.18 no.2
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• pp.157-175
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• 2012

It is difficult to evaluate the performance of process innovation of e-procurement which has large scale and complex processes. The existing evaluation methods for measuring the effects of process innovation have been mainly done with statistically quantitative methods by analyzing operational data or with qualitative methods by conducting surveys and interviews. However, these methods have some limitations to evaluate the effects because the performance evaluation of e-procurement process innovation should consider the interactions among participants who are active either directly or indirectly through the processes. This study considers the e-procurement process as a complex system and develops a simulation model based on MAS(Multi-Agent System) to evaluate the effects of e-procurement process innovation. Multi-agent based simulation allows observing interaction patterns of objects in virtual world through relationship among objects and their behavioral mechanism. Agent-based simulation is suitable especially for complex business problems. In this study, we used Netlogo Version 4.1.3 as a MAS simulation tool which was developed in Northwestern University. To do this, we developed a interaction model of agents in MAS environment. We defined process agents and task agents, and assigned their behavioral characteristics. The developed simulation model was applied to G2B system (KONEPS: Korea ON-line E-Procurement System) of Public Procurement Service (PPS) in Korea and used to evaluate the innovation effects of the G2B system. KONEPS is a successfully established e-procurement system started in the year 2002. KONEPS is a representative e-Procurement system which integrates characteristics of e-commerce into government for business procurement activities. KONEPS deserves the international recognition considering the annual transaction volume of 56 billion dollars, daily exchanges of electronic documents, users consisted of 121,000 suppliers and 37,000 public organizations, and the 4.5 billion dollars of cost saving. For the simulation, we analyzed the e-procurement of process of KONEPS into eight sub processes such as 'process 1: search products and acquisition of proposal', 'process 2 : review the methods of contracts and item features', 'process 3 : a notice of bid', 'process 4 : registration and confirmation of qualification', 'process 5 : bidding', 'process 6 : a screening test', 'process 7 : contracts', and 'process 8 : invoice and payment'. For the parameter settings of the agents behavior, we collected some data from the transactional database of PPS and some information by conducting a survey. The used data for the simulation are 'participants (government organizations, local government organizations and public institutions)', 'the number of bidding per year', 'the number of total contracts', 'the number of shopping mall transactions', 'the rate of contracts between bidding and shopping mall', 'the successful bidding ratio', and the estimated time for each process. The comparison was done for the difference of time consumption between 'before the innovation (As-was)' and 'after the innovation (As-is).' The results showed that there were productivity improvements in every eight sub processes. The decrease ratio of 'average number of task processing' was 92.7% and the decrease ratio of 'average time of task processing' was 95.4% in entire processes when we use G2B system comparing to the conventional method. Also, this study found that the process innovation effect will be enhanced if the task process related to the 'contract' can be improved. This study shows the usability and possibility of using MAS in process innovation evaluation and its modeling.

• Korean Journal of Community Nutrition
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• v.20 no.3
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• pp.220-235
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• 2015

Objectives: The purpose of this study was to investigate how clinical nutrition services is provided at a long term care hospital in Korea and to investigate job satisfaction levels of the clinical dietitians. Methods: Survey questionnaire was sent to dietitians working at a long term care hospital in Korea. The participating hospitals (n=240) were randomly selected from 1,180 long- term care hospitals using a stratified sampling method. A total of 134 long term care hospital s and 223 dietitians completed the survey of clinical nutrition service s and job satisfaction questionnaires The job satisfaction questionnaire included 27 job satisfaction questions on task, stability vision, working conditions, and relationship areas. Results: The average nutritional screening rate was 17.9% and the rate of computerized nutritional screening system was 9.7% in the participating hospitals. Nutritional intervention rate was only 3.2% of all patients. KOIHA (Korea Institute for Healthcare Accreditation) accreditated hospitals showed only 50% performance rate of nutrition service evaluation area. This shows that after achieving KOIHA accredition, many hospitals do not emphasize the performance of nutritional services. The job satisfaction scores in all four areas ranged from 2/5 to 3/5, implying generally low job satisfaction level in hospital dietitians. Linear regression analysis results showed that the "hospital adequacy grade" type was a significant predictor of job satisfaction level for two areas (working conditions & relationship). Conclusions: There is a need to provide proper standardized clinical nutrition services as a primary treatment and we observed large variations in the quality of nutritional service s in long term care hospitals. Therefore, government and local hospitals have to work on implementing nutritional programs and policies for improved service and care.

• Journal of Technology Innovation
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• v.25 no.4
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• pp.263-284
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• 2017

The purpose of this research is to analyze the performance of national R&D projects and to find out measures to improve the performance indicators, focusing on energy HRD projects. The main analysis target is 86 energy manpower projects supported since 2010. The performance indicators of the energy HRD projects are related to the research capacity, the number of emission workers, industry-university linkage, job creation and so on, and analyzed by using the 11 indicators of human resource performance index called KPI index. As a result of analyzing the attainment level of the proposed target by task, the index with the highest achievement level is the corporation linkage rate, and the index with the lowest achievement level is the participating company employment. As a result of examining the effects of job creation in company - linked activities, it was found that the greater the number of participating companies in the business, the greater the employment creation effect of the number of internships. As a result of the above analysis, the following policy alternatives are proposed. First, it is necessary to consider adding indicators that can express the quality performance of the business and performance indicators that can express actual business linkages. Second, it is necessary to strengthen the management of differentiated performance indicators according to policy performance targets and major target groups. Third, it is necessary to improve information input and accumulation system along with improvement of performance index.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.3
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• pp.1121-1139
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• 2015

In texture-plus-depth format, depth map compression is an important task. Different from normal texture images, depth maps have less texture information, while contain many homogeneous regions separated by sharp edges. This feature will be employed to form an efficient depth map coding scheme in this paper. Firstly, the histogram of the depth map will be analyzed to find an appropriate threshold that segments the depth map into the foreground and background regions, allowing the edge between these two kinds of regions to be obtained. Secondly, the two regions will be encoded through rate distortion optimization with a shape adaptive wavelet transform, while the edges are lossless encoded with JBIG2. Finally, a depth-updating algorithm based on the threshold and the depth range is applied to enhance the quality of the decoded depth maps. Experimental results demonstrate the effective performance on both the depth map quality and the synthesized view quality.

• The Journal of Korea Robotics Society
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• v.13 no.3
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• pp.151-156
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• 2018

Military robots are expected to play an important role in the future battlefield, and will be actively engaged in dangerous, repetitive and difficult tasks. During the robots perform the tasks a human operator controls the robots in a supervisory way. The operator recognizes battlefield situations from remote robots through an interface of the operator control center, and controls them. In the meantime, operator workload, controller interface, robot automation level, and task complexity affect robot operability. In order to assess the robot operability, we have developed ROSim (Robot Operational Simulator) incorporating these operational factors. In this paper, we introduce the results of applying ROSim experimentally to the assessment of reconnaissance robot operability in a battle field. This experimental assessment shows three resulting measurements: operational control workload, operational control capability, mission success rate, and discuss its applicability to the defense robot research and development. It is expected that ROSim can contribute to the design of an operator control center and the design analysis of a human-robot team in the defense robot research and development.

• Journal of the Korea Institute of Building Construction
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• v.11 no.3
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• pp.238-246
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• 2011

Choosing the best-performance materials is a crucial task for the successful completion of a project in the construction field. In general, the process of material selection is performed through the use of information by a highly experienced expert and the purchasing agent, without the assistance of logical decision-making techniques. For this reason, the construction field has considered various artificial intelligence (AI) techniques to support decision systems as their own selection method. This study proposes the application of a systematic and efficient support vector machine (SVM) model to select optimal exterior materials. The dataset of the study is 120 completed construction projects in South Korea. A total of 8 input determinants were identified and verified from the literature review and interviews with experts. Using data classification and normalization, these 120 sets were divided into 3 groups, and then 5 binary classification models were constructed in a one-against-all (OAA) multi classification method. The SVM model, based on the kernel radical basis function, yielded a prediction accuracy rate of 87.5%. This study indicates that the SVM model appears to be feasible as a decision support system for selecting an optimal construction method.