• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.456-462
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• 2012

In the new changing scenario, the goal of agriculture is shifting from traditional to sustainable and environment-friendly agriculture. Therefore, in this experiment, we analyzed economic efficiency of two methods of rice cultivation i.e. new cultural method and conventional method, at farmers' fields. In the new cultural method, cost of materials and machines (rice-transplanting and sowing machine) was found 245% higher than the conventional method. Depreciation of cost and working hours were also higher in the new cultural method by 1.9 and 1.1 time, respectively. However, cost of seeds and seedbed soil were 44.0% and 49.2% lower and total material cost was 4.4% lower than the conventional method. In the new cultural method, overall working cost of nursery raising and transplanting per 10a was 229.8% higher than the conventional method. However, in spite of high input cost, yield of rice in new cultural method was higher by 6.7% than the conventional method. Our results showed that new cultural method was better than the conventional method except the input cost. If government provide 80% subsidy for machine cost then its input cost will be reduced by 45.4% than the conventional method.

• Journal of Preventive Medicine and Public Health
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• v.43 no.6
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• pp.523-534
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• 2010

Objectives: We assessed impact of performance reporting information about the readmission rate, length of stay and cost of hip hemiarthroplasty. Methods: The data are from a nationwide claims database, National Quality Improvement Project database, of Health Insurance Review & Assessment Service in Korea. From January 2006 to April 2008, we received information of length of stay, readmission within 30 days, cost of 22 851 hip hemiarthroplasty episodes. Each episodes has retained the diagnoses of comorbidities and demographics. We used time-series analysis to assess the shifting of patients selections, between high volume (over 16 operations in a year) and low volume institutions, after performance reporting (December 2007). The changes of quality (readmission, length of stay) and cost were evaluated by multilevel analysis with adjustment of patient's factors and institutional factors after performance reporting. Results: As compared with the before performance reporting, the proportion of patients who choose the high volume institution, increased 3.45% and the trends continued 4 months at marginal significance (p = 0.059). After performance reporting, national average readmission rate, length of stay were decreased by 0.49 OR (95% CI=0.25 - 0.95) and 10% (${\beta}$=-0.102, p<0.01) and cost was not changed (${\beta}$=-0.01, p=0.27). The high volume institutions were more decreased than low volume in length of stay. Conclusions: After performance reporting, readmission rate, length of stay were decreased and the patient selections were marginally shifted from low volume institutions to high volume institutions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.10
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• pp.2619-2627
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• 2009

The ground fault is occupying 70% among the total number of faults in ungrounded distribution power system. When the ground fault occurs in ungrounded system, the fault current is so small that it is hard to detect. But fault handling is very important because to continue power supply during fault conditions may cause the fault spreading and the distribution device in trouble. This paper presents the fault line detection method by using GPT signal detecting zero sequence voltage, and the fault section detection method by detecting whether GPT signal is disappeared or not during shifting normally open switch, which is connecting switch between distribution lines with open state in order to restore the outage area under emergency situation, and during isolating each section one by one which belongs to the fault line. This method is efficient because there is no whole power interruption during the fault section detection, and it is possible to perform both the fault section detection and the service restoration for the outage area at the same time, and it can apply to various distribution system configuration. Program for the fault restoration was developed applying proposed method, and it has been validated by applying to the pilot project of distribution automation system in Vietnam which has the ungrounded distribution system.

• Polymer(Korea)
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• v.25 no.3
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• pp.359-366
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• 2001

Isothermal physical aging of a glass fiber/epoxy composite was examined at different aging temperatures ($T_a$) and degrees of conversion (monitored by the glass transition temperature, $T_g$) by means of the TBA torsion pendulum technique. The range of aging temperature was from 10 to $130^{\circ}C$ : the conversion was systematically changed from $T_g$=$76^{\circ}C$ to $T_g$=$177^{\circ}C$ (fully crosslinked). The effect of isothermal physical aging was manifested as perturbations of the modulus and mechanical loss vs. temperature in the vicinity of $T_a$ for all conversions. The rate of isothermal physical aging determined from the change of modulus with aging time at fixed aging temperature decreased and then increased with increasing conversion below T$_{a}$=9$0^{\circ}C$. There exists a superposition in aging rate vs. ($T_g$ -$T_a$) by shifting horizontally and vertically. This implies that the physical aging process is independent of the change of chemical structure as conversion proceeds. It has been found that water absorbed at the aging temperature below $70^{\circ}C$ during isothermal physical aging lowers the apparent aging rate. It is due to the absorbed water molecules forming strong polar interactions with hydroxyl group on network chain and reducing the segmental mobility during the physical aging.g.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.2
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• pp.128-139
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• 2017

Railway is one of the public transportation systems along with shipping and aviation. With the recent introduction of high speed train, its proportion is increasing rapidly, which results in the higher risk of catastrophic failures. The wheel bearing to support the train is one of the important components requiring higher reliability and safety in this aspect. Recently, many studies have been made under the name of prognostics and health management (PHM), for the purpose of fault diagnosis and failure prognosis of the bearing under operation. Among them, the most important step is to extract a feature that represents the fault status properly and is useful for accurate remaining life prediction. However, the conventional features have shown some limitations that make them less useful since they fluctuate over time even after the signal de-noising or do not show a distinct pattern of degradation which lack the monotonic trend over the cycles. In this study, a new method for feature extraction is proposed based on the observation of relative frequency energy shifting over the cycles, which is then converted into the feature using the information entropy. In order to demonstrate the method, traditional and new features are generated and compared using the bearing data named FEMTO which was provided by the FEMTO-ST institute for IEEE 2012 PHM Data Challenge competition.

• Journal of the Korean Society of Costume
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• v.25
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• pp.249-268
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• 1995

Parody has recently prevailed as one of the important techniques of creation in art. The purposes of this study are to reaffirm the pos-ition of fashion as an art by clarifying parody depicted in fashion and to make an opportunity to reconsider the meaning of creation in fashion design through the significance of par-ody. For these purposes, documentary studies about parody in literature and art which had been discussed more often were preceded as a framework of this research. framework of this research. Basedd upon that, parody phenomena in fashion as well as art were analyzed. The synthetic results are as follows ; 1. Parody is a kind or critical technique and can be conceived as a process of creation. The established primary style (material) which is well-known and familiar is imitated and then is recreated in new manner through the three types of parodization, that is, the change of its external form, the change of its internal mean-ing and the shift from its place (i.e. displace-ment). 2. Parody in fashion is also analyzed based upon the three types of parodization which designer's will and expression is necessarily required. First, the parody through the change of external form is to have its effect of novelty, unexpectedness, playfulness, wit, mackery, satire, irony, paradox by changing the form of the original through imitation with similarity, transformation, exaggeration, em-phasis. Second, the parody through the change of internal meaning is to bring about paradox, irony, contempt, satire, unex-pectedness by applying the original to inappro-priate subject through its substitution, inver-sion. Third, the parody through displacement is to pursue a jarring incongruity that results from shifting the original to other context. Its effect consists of paradox, unexpectedness, playfulness, ridicule, mockery, satire, irony. In general, the parody technique in fashion can be used to have an intention of expressing seriousness, playfulness, satire, grotesque. The representative designers using the parody technique are Lagerfeld, Ricci, YSL, Yama-moto, Castelbajac, Gaultier, Mugler, West-sood, Steiner and so on. 3. Parody is the technique which imitates and then recreates the preceding style ; is at the same time the method which challenges the existing concept of originality-singleness and uniqueness. It reflects the more flexible concept of modern creation in art as well as fashion. The imitation as the creation, the characteristic of parody is recognized as an creative expressiveness, publicity, intention. Thus it differenciates from copy which is uncritical mimicry.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.9
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• pp.54-62
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• 2015

Although NAND flash-based SSD (Solid-State Drive) provides superior performance in comparison to HDD (Hard Disk Drive), it has a major drawback in write endurance. As a result, the lifetime of SSD is determined by the workload and thus it becomes a big challenge in current technology trend of such as the shifting from SLC (Single Level Cell) to MLC (Multi Level cell) and even TLC (Triple Level Cell). Most previous studies have dealt with wear-leveling or improving SSD lifetime regarding hardware architecture. In this paper, we propose the optimal configuration of host I/O stack focusing on file system, I/O scheduler, and link power management using JEDEC enterprise workloads in terms of WAF (Write Amplification Factor) which represents the efficiency perspective of SSD life time especially for host write processing into flash memory. Experimental analysis shows that the optimum configuration of I/O stack for the perspective of SSD lifetime is MinPower-Dead-XFS which prolongs the lifetime of SSD approximately 2.6 times in comparison with MaxPower-Cfq-Ext4, the best performance combination. Though the performance was reduced by 13%, this contributions demonstrates a considerable aspect of SSD lifetime in relation to I/O stack optimization.

• Transactions of the Korean Society of Mechanical Engineers
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• v.9 no.5
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• pp.590-597
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• 1985

A recursive geometric adaptive control method to compensate for machining straightness error in the finished surface due to tool deflection and guideway error generated by end milling process is developed. The relationship between the tool deflection and the feedrate is modeled by a modified Taylor's tool life equation. Without a priori knowledge on the variations off cutting parameters, time varying parameters are then estimated by an exponentially windowed recursive least squares method with only post-process measurements of the straightness error. The location error is controlled by shifting the milling bed in the direction perpendicular to the finished surface and adding a certain amount of feedrate with respect to the tool deflection model before cutting. The waviness error is compensated by adjusting the feedrate during machining. Experimental results show that location error is controlled within a range of fixturing error of the bed on the guideway and that about 60% reduction in the waviness error can be achieved within a few steps of parameter adaption under wide operating ranges of cutting conditions even if the parameters do not converge to fixed values.

• Journal of the Korean Wood Science and Technology
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• v.27 no.2
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• pp.15-22
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• 1999

Polymeric meterials that are used for noise and vibration damper in wood/polymer/wood sandwich composites, must have a high loss factor(tan ${\delta}$), and at the same time the storage modulus(E) of $5{\times}10^7$ to $10^9$ dyne/$cm^2$ must withstand over a wide temperature and frequency ranges. In this study, the series of epoxy resinlpolyacrylate interpenetrating polymer networks(IPNs) were synthesized by simultaneous polymerization. Their dynamic tensile properties were measured at 110Hz using Rheovibron instrument. Composite damping factor(tan ${\delta}_c$) and dynamic bending modulus($E_c,\;E_^{\prime\prime}c$) of wood/polymer/wood sandwich composites were measured at 110Hz using a Rheovibron in bending mode of vibration. These dynamic tensile studies indicated that cured epoxy resin/polyacrylates IPNs were semicompatible in the sense that both the shifting of T($E^{\prime\prime}_{max}$) or T(tan ${\delta}_{max}$) and the broadening of glass transition temperature range were observed. Especially, the cured Epikote871/P(n-BMA) IPNs of composition 70/30 to 50/50 showed a relatively high tan a and appropriate E' value over a wide temperature range; consequently the tan a e curves of wood/IPNs/wood sandwich composites was broadened over a wide temperature range.

• Journal of Internet Computing and Services
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• v.12 no.5
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• pp.171-179
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• 2011

In this paper it is hypothesized that word stimuli that are presented by Google’s search word, would improve the quality of the design solution, so this research examines the effect of related search word stimuli in concept generation and analyzes the results through the processes of creative cognition. In the process of concept generation, words are given as stimuli which are generated through Google's related search and these search words are given by 5 levels. Google search is based on the collaboration philosophy. People's participation and contribution recreate knowledge and information, so these renewed and related search words update in real time by people are used as stimuli. Two problems are provided with related search words. After the design concept generation the results are analyzed by 3 bases: the usage of related search words and those of frequency, creativity, and Finke's 12 Geneplore model. These are the results of the research. Many levels of related search words are used in design concept generation but especially higher levels which are more related to search words are more used than lower levels. The usage of multi words and conjunction with higher levels and lower levels words are observed in creative results. On the creative cognitive processes, it is more creative when using association and mental transformation with the related search words than using the related search words simply. Creative outputs also use conceptual interpretation, functional inference, and contextual shifting of creative cognitive processes of Finke's 12 Geneplore model.