• International Journal of Fuzzy Logic and Intelligent Systems
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• v.13 no.2
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• pp.100-105
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• 2013

In this study, we analyze the balance of quadruped walking robots. For this purpose, a simplified polygonal model of a quadruped walking configuration is considered. A boundary-range-based balance margin is used for determining the system stability of the polygonal walking configuration considered herein. The balance margin enables the estimation of the walking configuration's balance for effective walking. The usefulness of the balance margin is demonstrated through exemplary simulations. Furthermore, balance compensation by means of foot stepping is addressed.

• Nuclear Engineering and Technology
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• v.34 no.1
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• pp.68-79
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• 2002

The approach for evaluating the critical heat flux (CHF) margin using the departure from nucleate boiling ratio (DNBR) concept has been widely applied to PWR core design, while DNBR in this approach does not indicate appropriately the CHF margin in terms of the attainable power margin-to-CHF against a reactor core condition. The CHF power margin must be calculated by increasing power until the minimum DNBR reaches a DNBR limit. The Critical Power Ratio (CPR), defined as the ratio of the predicted CHF power to the operating power, is considered more reasonable for indicating the CHF margin and can be calculated by a CPR orrelation based on the heat balance of a test bundle. This approach yields directly the CHF power margin, but the calculated CPR must be corrected to compensate for many local effects of the actual core, which are not considered in the CHF test and analysis. In this paper, correction of the calculated CPR is made so that it may become equal to the DNB overpower margin. Exemplary calculations showed that the correction tends to be increased as power distribution is more distorted, but are not unduly large.

• Korean Journal of Applied Biomechanics
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• v.27 no.3
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• pp.205-210
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• 2017

Objective: The aim of the study was to investigate the age-related ability of dynamic balance recovery through perturbation response during standing. Method: Six older and 6 younger adults participated in this study. External perturbation during standing as pulling force applied at the pelvic level in the anterior direction was provided to the subject. The margin of stability was quantified as a measure of postural stability or dynamic balance recovery, and using principal component analysis (PCA), the regularity of the margin of stability (MoS) was calculated. Results: Our results showed that in the older adult group, 60.99% and 28.63% of the total variance were captured using the first and second principal components (PCs), respectively, and in the younger adult group, 81.95% and 10.71% of the total variance were captured using the first and second PCs, respectively. Conclusion: Ninety percent of the total variance captured using the first two PCs indicates that the older adults had decreased regularity of the MoS than the younger adults. Thus, the results of the present study suggest that aging is associated with non-regularity of dynamic postural stability.

• The Journal of Fisheries Business Administration
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• v.35 no.1
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• pp.169-191
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• 2004

This Study attempts to analysis the degrees of the efficiency of fisheries marketing channel's effectiveness, which are traditional marketing channel's effectiveness of fisheries wholesale markets and Discount Store's effectiveness such as margin, marketing performance. The study methodologies include not only a field sample survey but also a field interview. The results of this study are summarized as follows. First, at the numbers of fisheries marketing channel's margin factors, traditional marketing channel's margin factors are more than discount store's margin factors. Secondly, at the comparative study result of marketing channel margin efficiency, traditional marketing channel's prices are similar to discount store's prices. That is, consumers have bought similar retail price's seafood products through traditional marketing channels as well as discount stores cannels. Finally, however most consumers prefer discount stores to traditional retail stores because of discount store's multi-functions such as assortment of goods, freshness, exchange, refund and employee's kindness. In conclusion, the most important factor of fisheries marketing management is to realize the appropriate balance between marketing margin and consumer satisfaction.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.11
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• pp.1495-1504
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• 2013

Renewable energy integration and increased system complexities make system operator maintain supply and demand balance harder than before. To keep the grid frequency in a stable range, an appropriate spinning reserve margin should be procured with consideration of ever-changing system situation, such as demand, wind power output and generator failure. This paper propose a novel concept of dynamic reserve, which arrange different spinning reserve margin depending on time. To investigate the effectiveness of the proposed dynamic reserve, we developed a new short-term reliability criterion that estimates the probability of a spinning reserve shortage events, thus indicating grid frequency stability. Uncertainties of demand forecast error, wind generation forecast error and generator failure have been modeled in probabilistic terms, and the proposed spinning reserve has been applied to generation scheduling. This approach has been tested on the modified IEEE 118-bus system with a wind farm. The results show that the required spinning reserve margin changes depending on the system situation of demand, wind generation and generator failure. Moreover the proposed approach could be utilized even in case of system configuration change, such as wind generation extension.

• Journal of Biomedical Engineering Research
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• v.32 no.1
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• pp.7-14
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• 2011

This study suggested an optimized algorithm for detecting the loss of balance(LOB) in the seated position. And the sensitivity analysis was performed in order to identify the role of each design variable in the algorithm. The LOB algorithm consisted of data processing of measured signals, an internal model of the central nervous system and a control error anomaly(CEA) detector. This study optimized design variables of a CEA detector to obtain improved values of the success rate(SR) of detecting the LOB and the margin time(MT) provided for preventing the falling. Nine healthy adult volunteers were involved in the experiments. All the subjects were asked to balance their body in a predescribed seated posture with the rear legs of a four-legged wooden chair. The ground reaction force from the right leg was measured from the force plate while the accelerations of the chair and the head were measured from a couple of piezoelectric accelerometers. The measured data were processed to predict the LOB using a detection algorithm. Variables S2, h2 and hd are related to the detector: S2 represents a data selecting window, h2 a time shift and hd an operating period of the LOB detection algorithm. S2 was varied from 0.1 to 10 sec with an increment of 0.1 sec, and both h2 and hd were varied from 0.01 to 1.0 sec with an increment of 0.01 sec. It was found that the SR and MT were increased by up to 9.7% and 0.497 sec comparing with the previously published case when the values of S2, h2 and hd were set to 4.5, 0.3 and 0.2 sec, respectively. Also the results of sensitivity analysis showed that S2 and h2 had considerable influence on the SR while these variables were not so sensitive to the MT.

• Korea Journal of Hospital Management
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• v.9 no.1
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• pp.22-45
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• 2004

This study was performed to identify factors affecting the profitability of private hospitals in Korea different and to make informations that could be very helpful to hospitals in improving profitability. Data used in this study were collected from 112 hospitals with complete general data of present conditions as well as financial statements(balance sheets, income statements). They were chosen from hospitals that passed the standardization audit undertaken by the Korean Hospital Association from 1998 to 2001 for the purpose of accrediting training hospitals. The dependent variables were used operating margin to total assets and operating margin to gross revenues as proxy indicators for profitability. The independent variables were ownership type, location, bed size, period of establishment, debt to total assets, current ratio, fixed ratio, total asset turnover, average length of stay, bed occupancy rate, admission ratio of outpatients, personnel costs per adjusted inpatient, and fiscal years. The factors had significantly positive effect on operating margin to total assets and operating margin to gross revenues were bed size, total asset turnover. And the factors had significantly negative effect on operating margin to total assets and operating margin to gross revenues were period of establishment, debt to total assets, average length of stay, personnel costs per adjusted inpatient. The adjusted $R^2$ of multiple regression equation was 25.2%, 21.4% respectively. It is very important for private hospitals to improve profitability by raising total asset turnover, and reducing debt to total assets, average length of stay, and personnel costs per adjusted inpatient using the rational and efficient business strategy.

• Journal of the Korean Institute of Intelligent Systems
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• v.21 no.6
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• pp.673-678
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• 2011

This paper analyzes the standing balance of four-legged robots which are useful for delivering objects or investigating of information. For this, we specify an effective model of general four-legged robots and propose a boundary condition based on the standing stability of the four-legged walking. To verify such a standing balance, we consider some exemplary free motions at the standing mode of the robot and discuss on the robot's balance margin. The analysis specified in this paper will be applicable for effective balancing control of various quadruped robotic walking.

• Journal of Korean Clinical Health Science
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• v.4 no.2
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• pp.582-592
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• 2016

Purpose. For more effective hospital management, it analyzes the trend through general characteristics, balance sheet, income statement, and financial ratio analysis, grasps the causes of the problems, and analyzes management of the hospital in order to use the result as baseline data for development of the hospital in the future. Methods. The collected data of 3 years from 2011 to 2013 about 3 tertiary hospitals in metropolitan cities from Alio (provider of public institution information; www.alio.go.kr), Health Insurance Review & Assessment Service (www.hira.or.kr), and the website of the Ministry of Health and Welfare (www.mw.go.kr) were analyzed and general characteristics, balance sheet, income statement, and financial ratio, analysis are used as data. Results & Conclusions. From the result of data analysis from 2011 to 2013, general characteristics, balance sheet, income statement, financial ratio analysis, and pie charts could lead to conclusions as follows. In the result of comprehensive analysis, the 3 tertiary hospitals showed increase of fixed expense due to extension of the buildings and so did the scale of fund and asset. Although medical revenue increased, the margin of increase for medical expense was greater than that of medical revenue, which consequently led to loss. In prediction for the 3 tertiary hospitals based on characteristics so far, it is expected to see improved revenue structure after building extension is completed, but it is necessary to exert management effort to maintain its optimal level by enhancement in stability of management and inventory turnover through management of inventories.

• Korea Journal of Hospital Management
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• v.18 no.3
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• pp.43-61
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• 2013

The purpose of this study is to analyze the relations between publicness and profitability of national university hospitals in Korea. Finance and management data from 2008 to 2010 were collected from balancing accounts and annual reports in 13 national university hospitals. The dependant variables are used profitability indicators which are operating margin, net profit to gross revenues, normal profit to gross revenues. The independent variables are publicness indicators which are medical social work, ratio of medical aid in inpatients, ratio of medical aid in outpatients, publicness index. The results show that operating margin, net profit to gross revenues in profitability indicators are affected by medical social work in publicness indicators. Normal profit to gross revenues in profitability indicators is strong related to medical social work and hospital province in publicness indicators. Based on these results, this study suggests implications to balance the publicness and the profitability in national university hospitals.