• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.5
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• pp.40-52
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• 2010

A mobile ad hoc network is instant and heuristic, and it is also vulnerable and volatile. Since topology and route changes are frequent, no single routing protocol designed for a conventional network performs well. Some protocols suffer from significant performance degradation when the number of nodes increases, or when nodes become highly mobile. In this paper we investigate a way to adaptively select a routing protocol that fits to the real-time network conditions. The first phase of our study is to analyze the performances of two classes of routing protocols under various network scenarios. The second phase consists of constructing a routing protocol selection reference. All nodes continue to monitor the status of neighbor nodes and control packets exchanged. Then, the aggregated information is periodically compared against the protocol selection reference. The selected routing protocol is maintained throughout the network until the network property changes substantially. The performance of the proposed algorithm is verified by a set of computer simulations using the OPNET modeler. The experimental results show that selectively changing routing protocol adaptive to the network conditions greatly improves the efficacy of bandwidth utilization.

• Quality Improvement in Health Care
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• v.1 no.2
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• pp.60-72
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• 1994

Background: The number of outpatients visiting large university teaching hospitals has increased drastically with the introduction of a nationwide health care insurance in 1989 and the improvement of the socio-economic status of the population. This resulted in long waiting times for services, particularly prescribed drugs, which have been patients' chief complaints. Hospitals have tried to solve the problem with limited success because their approach lacked comprehensive research. The objective of this study is to investigate associations between waiting times and variables defining a total work system. Methods: Data for the outpatient pharmacy department in a tertiary care university teaching hospital located in Seoul was analyzed to achieve the study objective. Associations of pharmacy system variables -- work load, work force, pharmacist work schedule, machine problems, and inventory control -- with mean and 99th percentile of waiting times were examined by the hierarchical stepwise regression method. Day was a unit of the analyses. Results: The regression models explained 65.8% of variance in the mean waiting time and 61.34% in the 99th percentile of waiting times. The break-down of the printer for drug envelops, Automatic Tablet Counters (ATCs), and main computer system lasted longer than 30 minutes increased the mean for 7.7 minutes, 4.5 minutes, and 7.0 minutes, respectively, and the 99th percentile for 14.8 minutes, 9.0 minutes, and 15.7 minutes, respectively. Concerning the work force, study results showed that there were significant differences in the productivity of pharmacists with work experience more than three years, one to three years, and less than one year, and showed that peak time aid work by pharmacists at job assignments other than the outpatient pharmacy, part-time pharmacists, and the installation of ATCs were effective in reducing waiting times, Finally, study findings indicated that the operational policy of work assignment and rotation schedule, supply and inventory of drugs at work tables, and readiness for undisrupted work during the work hours could have a significant effect on waiting times. Conclusion: The study results indicated that efforts to reduce waiting times for prescribed drugs should be geared toward every components of the pharmacy work system ranging from work schedule of pharmacists and supply of dugs at work tables. These findings should provide hospital managers with right directions in battling the problem.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.6
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• pp.497-504
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• 2012

Finite element analysis is to approximate a geometry model developed in computer-aided design(CAD) to a finite element model, thus the conventional shape design sensitivity analysis and optimization using the finite element method have some difficulties in the parameterization of geometry. However, isogeometric analysis is to build a geometry model and directly use the functions describing the geometry in analysis. Therefore, the geometric properties can be embedded in the NURBS basis functions and control points so that it has potential capability to overcome the aforementioned difficulties. In this study, the isogeometric structural analysis and shape design sensitivity analysis in the generalized curvilinear coordinate(GCC) systems are discussed for the curved geometry. Representing the higher order geometric information, such as normal, tangent and curvature, yields the isogeometric approach to be the best way for generating exact GCC systems from a given CAD geometry. The developed GCC isogeometric structural analysis and shape design sensitivity analysis are verified to show better accuracy and faster convergency by comparing with the results obtained from the conventional isogeometric method.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.1
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• pp.71-78
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• 2020

In the case of power generation using renewable energy, power production may not be smooth due to the influence of the weather. The energy storage system (ESS) is used to increase the efficiency of solar and wind power generation. ESS has been continuously fired due to a lack of battery protection systems, operation management, and control system, or careless installation, leading to very big casualties and economic losses. ESS stability and battery protection system operation management technology is indispensable. In this paper, we present a battery level calculation algorithm and a failure prediction algorithm for ESS optimization and stable operation. The proposed algorithm calculates the correct battery level by accumulating the current amount in real-time when the battery is charged and discharged, and calculates the battery failure by using the voltage imbalance between battery cells. The proposed algorithms can predict the exact battery level and failure required to operate the ESS optimally. Therefore, accurate status information on ESS battery can be measured and reliably monitored to prevent large accidents.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.6 no.2
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• pp.228-239
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• 1999

In 1990 Home Care Education Programs started when legislation established certification for Home Care Nurses. The Ministry of Health and Welfare proposed a home care education curriculum which has 352 class hours and 248 hours of 'family nursing and practice'. Though Home Care Education Programs have been offered in 11 home care educational institutes, there has been no formal revision for the home care education programs. Also a first and second home care demonstration projects have been carried out, but there has been no research on outcomes for home care education as applied in home care practice. The purposes of this study were to identify the important content areas for home care nursing as perceived by home care nurses, and to identify their clinical competence in each of these areas, and from these to identify the education needs. The sample was 107 home care nurses who were working in home care demonstration hospitals and community-based institutions which have been offering home care services. Responses were received from 88 nurses, comprising a 82.2% return rate, and 86 were included in the final analysis. The instrument used was a modification of the instrument developed by Caie-Lawrence et(1995) and Moon's(1991) instrument on home care knowledge. The instrument's Cronbach's coefficient was 0.982. Among the respondents, 64% were working at home care demonstration hospitals and 36% were working at community-based institutions. Their home care experiences were from one month to six years, with a mean of 20.6 months. The importance rating for home care education content was 3.42 0.325, which means importance was rated relatively high. Technical aspects of home care were identified the most important. Five items 'education skill', 'counseling skill', 'interview skill', 'wound care skill', 'bed sore care skill' received 100% importance ratings. The competency rating was 2.87 0.367 and 'technical aspects of home care' was the highest, and 'application to home care skill' was the lowest. Home care nurses' education needs were identified and compared to the importance ratings and competency ratings. Eleven items were identified as the highest in the importance areas and eleven items were in the lowest competency areas. High importance ratings matched with low competency ratings determined training needs, but there was no matching items in this study. In the lowest competency areas four items were excluded, because of not being applicable in current home care practice. Therefore total eighteen items were identified as home care education needs. These items are 'bed sore care skill', 'malpractice', 'wound care skill', 'general infection control', 'change and management of tracheostomy tubes', 'CVA patient care', 'Hospice care', 'pain management', 'urinary catheterization and management', 'L-tube insertion and managements', 'Respirator use and management skill', 'infant care', 'prevention to burnout', 'child assessment', 'CAPD', 'infant assessment', 'computer literacy', and 'psychiatry patient care'.

• Journal of Digital Convergence
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• v.10 no.10
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• pp.333-338
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• 2012

Human resource management is bringing the various changes with the IT technology. In particular, if HRM is non-scientific method such as group management, physical plant, working hours constraints, personal contacts, etc, the current enterprise human resources management(e-HRM) appeared in the individual dimension management, virtual workspace (for example: smart work center, home work, etc.), working time flexibility and elasticity, computer-based statistical data and the scientific method of analysis and management has been a big difference in the sense. Therefore, depending on changes in the environment, companies have introduced a variety of techniques as RFID card, fingerprint time & attendance systems in order to build more efficient and strategic human resource management system. In this paper, time and attendance, access control management system was developed using multi camera for 2D and 3D face recognition technology-based for efficient enterprise human resource management. We had an issue with existing 2D-style face-recognition technology for lighting and the attitude, and got more than 90% recognition rate against the poor readability. In addition, 3D face recognition has computational complexities, so we could improve hybrid video recognition and the speed using 3D and 2D in parallel.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.37 no.5
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• pp.94-104
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• 2000

The accuracy and reliability of the target tracking is very critical issue in the design of automotive collision warning radar A significant problem in multi-target tracking (MTT) is the target-to-measurement data association If an incorrect measurement is associated with a target, the target could diverge the track and be prematurely terminated or cause other targets to also diverge the track. Most methods for target-to-measurement data association tend to coalesce neighboring targets Therefore, many algorithms have been developed to solve this data association problem. In this paper, a new multi-target data association method based on order statistics is described The new approaches. called the order statistics probabilistic data association (OSPDA) and the order statistics joint probabilistic data association (OSJPDA), are formulated using the association probabilities of the probabilistic data association (PDA) and the joint probabilistic data association (JPDA) filters, respectively Using the decision logic. an optimal or near optimal target-to-measurement data association is made A computer simulation of the proposed method in a heavy cluttered condition is given, including a comparison With the nearest-neighbor CNN). the PDA, and the JPDA filters, Simulation results show that the performances of the OSPDA filter and the OSJPDA filter are superior to those of the PDA filter and the JPDA filter in terms of tracking accuracy about 18% and 19%, respectively In addition, the proposed method is implemented using a developed digital signal processing (DSP) board which can be interfaced with the engine control unit (ECU) of car engine and with the d?xer through the controller area network (CAN)

• The Journal of Society for e-Business Studies
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• v.20 no.1
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• pp.183-199
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• 2015

Due to the Four Major Rivers Restoration Project, Nakdong River Estuary Barrage's designed flood quantity has been largely increased, and this has caused to construct several drainage gates at the right side of Eulsukdo island to secure the safety of downstream river area. For successful functioning of Nakdong River Estuary Barrage, such as flood control, disaster prevention, and the securing of sufficient water capacity, drainage gates at the both sides of island have to operate systematically and reliably. To manage this under restricted personnel and resources, we have implemented the IOS (Integrated Operation System) by integrating previous facilities and resources via information and communication technologies. The IOS has been designed to have higher availability and fault tolerance to function continuously even with the partial system's failure under the emergency situation like flood. Operators can use the system easily and acknowledge alarms of facilities through its IWS (Integrated Warning System) earlier. Preparing for Integrated Water Resources Management and Smart Water Grid, the architecture of IOS conformed to open system standards which will be helpful to link with the other systems easily.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.3
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• pp.64-70
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• 2016

The recent development of modern weapon system by SOS (System of System) has required users to have more exact decision making. It is possible to achieve the control of complex weapon system more efficiently and effectively by increasing usability. Accordingly, many studies on graphical display have been conducted for several years in the field of HCI (Human Computer Interaction) and GUI (Graphic User Interface), starting from its design stage. Therefore, this paper focuses on evaluating the system GUI usability and analyzing several important points based on performance model, which is a tool for the evaluation and the improvement of service quality. Performance Model, the main focus of this study, reflects user expectations (which is defined as user importance in this paper). The study consists of four steps. First, 34 checklists are drawn from the existing studies related to GUI usability evaluation by using a heuristic method, and then the checklists are matched with 11 weapon system design factors. Next, the study evaluates the importance of GUI element and the usability of weapon system "A" with the checklists twice respectively. Third, the performance of user importance ($P_i$) and the performance of usability ($P_u$) are calculated by modifying a numerical formula for normalization in this step. Finally, the study compares the approach it takes and the existing usability evaluation method, demonstrating that there is a significant difference between the two methods as a result. In addition, 4 improvement factors are suggested for weapon system "A" as "Shortcut" and "Description of Abbreviation," and so on. Although it is necessary to conduct more studies for higher reliability and validity of the results, this study is meaningful considering it takes a new point of view.

• Korean Journal of Remote Sensing
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• v.33 no.5_2
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• pp.631-640
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• 2017

The estimation of rice yield affects the income of farmers as well as the fields related to agriculture. Moreover, it has an important effect on the government's policy making including the control of supply demand and the price estimation. Thus, it is necessary to build the crop yield estimation model and from the past, many studies utilizing empirical statistical models or artificial neural network algorithms have been conducted through climatic and satellite data. Presently, scientists have achieved successful results with deep learning algorithms in the field of pattern recognition, computer vision, speech recognition, etc. Among deep learning algorithms, the SSAE (Stacked Sparse AutoEncoder) algorithm has been confirmed to be applicable in the field of forecasting through time series data and in this study, SSAE was utilized to estimate the rice yield in South Korea. The climatic and satellite data were used as the input variables and different types of input data were constructed according to the period of rice growth in South Korea. As a result, the combination of the satellite data from May to September and the climatic data using the 16 day average value showed the best performance with showing average annual %RMSE (percent Root Mean Square Error) and region %RMSE of 7.43% and 7.16% that the applicability of the SSAE algorithm could be proved in the field of rice yield estimation.