• Structural Engineering and Mechanics
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• v.39 no.6
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• pp.813-831
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• 2011

This paper presents an efficient version of Hilbert-Huang transform for nonlinear non-stationary systems analyses. An ensemble empirical mode decomposition (EEMD) is introduced to alleviate the problem of mode mixing between intrinsic mode functions (IMFs) decomposed by EMD. Yet the problem has not been fully resolved when a signal of a similar scale resides in different IMF components. Instead of using a trial and error method to select the "best" outcome generated by EEMD, a hybrid algorithm based on EEMD and EMD is proposed for multi-mode signal processing. The developed approach comprises the steps from a bandpass filter design for regrouping modes of the IMFs obtained from EEMD, to the mode extraction using EMD, and to the assessment of each mode in the marginal spectrum. A simulated two-mode signal is tested to demonstrate the efficiency and robustness of the approach, showing average relative errors all equal to 1.46% for various noise levels added to the signal. The developed approach is also applied to a real bridge structure, showing more reliable results than the pure EMD. Discussions on the mode determination are offered to explain the connection between modegrouping form on the one hand, and mode-grouping performance on the other.

• The Journal of Sustainable Design and Educational Environment Research
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• v.13 no.1
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• pp.75-85
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• 2014

In this study, the characteristics and the composition of the school groundrevels in Korea to identify the problem, were compared with Japan, where in geographic and culturally similar environment the composition of the school groundrevels analyzed. The spatial extent of this study is the development of metropolitan areas and small city within 10 years (range time) survey of the 34 elementary schools were analyzed. The results are as follows: First, the school groundrevels are flat step-like form of the composition for the same level of barrier-free should be provided. Second, if the lower places in slopes where to place buildings and playgrounds are placed in high places. Third, the external space and the interior space of the connection is the concept of fault tolerance and eliminate need for stairs. This study is a part of the urban Newtown and there are limitations to generalize the results. Therefore, this result on the general guidance of school groundrevel composition in order to objectify an additional studies are required.

• Journal of Power Electronics
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• v.14 no.1
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• pp.194-201
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• 2014

To increase the capacity of secondary cells, an appropriate serial composition of the battery modules is essential. The unbalance that may occur due to the series connection in such a serial composition is the main cause for declines in the efficiency and performance of batteries. Various studies have been conducted on the use of a passive or active topology to eliminate the unbalance from the series circuit of battery modules. Most topologies consist of a complex structure in which the Battery Management System (BMS) detects the voltage of each module and establishes the voltage balancing in the independent electrical power converters installed on each module by comparing the module voltage. This study proposes a new magnetic flux sharing type DC/DC converter topology in order to remove voltage unbalances from batteries. The proposed topology is characterized by a design in which all of the DC/DC convertor outputs connected to the modules converge into a single transformer. In this structure, by taking a form in which all of the battery balancing type converters share magnetic flux through a single harmonic wave transformer, all of the converter voltages automatically converge to the same voltage. This paper attempts to analyze the dynamic properties of the proposed circuit by using a Programmable Synthesizer Interface Module (PSIM), which is useful for power electronics analysis, while also attempting to demonstrate the validity of the proposed circuit through experimental results.

• Journal of ILASS-Korea
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• v.17 no.4
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• pp.171-177
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• 2012

To understand oxygenated fuel characteristics including spray penetration length and spray angle at a real engine ambient pressure condition, DME was injected into a high pressure chamber by a piezo injector common rail system. The piezo injector common rail system was able to apply steady injection pressure, rapid response, and accurate injection quantity. Injection and ambient pressure were varied to confirm a relation with spray form. Using a direct photographing technique, development process of DME spray was captured. DME injection quantity was enlarged linearly as increasing of the injection pressure. In the high pressure chamber, when the injection pressure was enlarged the penetration length and velocity were increased due to a big momentum of fuel particle at the same ambient pressure. When ambient pressure was increased, the DME spray penetration length and velocity were decreased since the high ambient density of nitrogen was acted as a resistance. Although the ambient pressure and injection pressure were varied, each case of spray angle was almost same since the spray angle had a connection of the injector nozzle geometry.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.4
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• pp.473-479
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• 2016

In connection with medical care, designs have been developed by forming relationships, typically supporting Visual Communication Design, Product Design and Environment Design healthcare environment aesthetically pleasing and convenient. However, in recent designs, expertise has increased, new areas specialized are merged with various areas and academic disciplines and subdivided. In addition, due to the development of technology, the design has been continuously changing, creating a new form of model by fusing with various industries, academics and services. Recognizing the changes and developments of these designs, we are promoting research on utilization of design in medical services, we can create a new value by getting out of design that we have limitedly used in areas of traditional design I will try to know about developing into a design.

• Fire Science and Engineering
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• v.23 no.2
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• pp.1-5
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• 2009

We studies wish to investigated establishment form of cabinet board, and confirm possibility of electrical disaster prevention through reappearance experiment of odor detection system. Established breaker consists of MCCB, RCD order in cabinet board for house, but industry is used together with. When imposed shock using shaker to terminal block that contact becomes in appropriate, flame was made sure. According to result that experiment attaching odor capsule in terminal block, capsule commissioned exactly by occurred heat. According to establishment position of sensor, difference of inspection time was about 10 seconds. Estimate odor inspection system by thing which electrical device accident prevention is available. When there is abnormal generated heat in connection of electric wire, accident prevention estimates that is possible by giving an alarm state of overheat to administrator.

• Journal of Pharmaceutical Investigation
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• v.40 no.spc
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• pp.97-102
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• 2010

A novel surface-attached solid dispersion is designed to improve the solubility and oral bioavailability of poorly water-soluble drugs without crystalline change. Accordingly, it draws increasing interest because of excellent stability and no pollution for accomplishing enhanced solubility and bioavailability, which have recently been highlighted in connection with a number of higher value-added poorly water-soluble drugs. In addition, excellent stability can be attained when the poorly water-soluble drugs are not dissolved but dispersed in water and provide no crystallinity change. This solid dispersion is given by means of attaching the dissolved carriers such as hydrophilic polymer and surfactant to the surface of dispersed drug particles followed by changing the hydrophobic drug to hydrophilic form. The aim of the present review is to outline the preparation, physicochemical property and bioavailability of novel surface-attached solid dispersion with improved solubility and bioavailability of poorly water-soluble drugs without crystalline change.

• Korean Institute of Interior Design Journal
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• v.20 no.2
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• pp.120-130
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• 2011

The purpose of this study is to propose cognitive ecological effects of fractal patterns in space design. This study investigated the perception and cognition problems regarding landscape patterns showing fractal properties from the cognitive perspective instead of the traditional speculative approach. In particular, the researcher has verified that fractal geometry theory and fractal pattern concept provide insight in space aesthetic values and cognitive effects. Research results are as follows. First, most environmentally-friendly fractal urban forms provide cognitive connectivity. In particular, this space provides a positive emotional response and preference to humans and displays self-organized complexity. This study found that such complexity of space form has characteristics corresponding to parallel cognitive structures of the human brain. Simultaneously, the researcher suggests that the fractal landscape pattern is an alternative for stiff and homogenized modern space. Second, fractal patterns provide hierarchical connectivity within the brain through continuous difference and repetition. In particular, self-similarities of fractal patterns administer significant visual grouping and coherence in human perception. It can be determined whether scaling coherence facilitates easier organization in cognitive organization. Third, fractal patterns in space design provide the basic method for achieving the connection between concept, construction, and urban factors. As a result, the researcher has suggested that scale distribution of geometrical factors, such as fractal patterns, an be a design method to connect various space typologies.

• Knowledge Management Research
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• v.15 no.4
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• pp.223-247
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• 2014

A large number of tasks being executed by individuals now are in a central requirement of the creative solutions consolidated with associates' multiple skills, knowledge bases and efforts who are capable of entertaining various viewpoints. Followed by such a variation, teams or groups were gradually settled in a major form of the enterprise's creative revelations. However, in spite of the consistent augmentation of team's application, researches of a group's ability that utilizes individual creative competence effectively are now in the excessively insufficient manner. Accordingly, this research is to verify mutual relationship between individual creativity and group creativity, and furthermore, to present integrative capability and knowledge sharing of the group as a distinctive variable to observe the mechanism of how the individual creativity becomes aggregated with the group creativity through a process. As a result, the relationship between the individual creativity and the group creativity was so significant that it showed that the integrative capability and knowledge sharing were mediated in the connection of the two variables. This research contributes to the comprehension of the relationship between individual and group creativity through the role of a group's integrative capability and knowledge sharing. In addition, further research direction with in-depth idea is presented to develop research on creativeness from the practical standpoint implicated in this research.

• Journal of Korean Society for Quality Management
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• v.30 no.3
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• pp.66-78
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• 2002

Process capability indices are being used as indicators for measurements of process capability for SPC of quality assurance system in industries. In view of the enhancement of customer satisfaction, process capability indices in which loss functions are used to deal with the economic loss In the processes deviated from the target, are in an adequate representation of the customer's perception of quality In this connection, the loss function has become increasingly important in quality assurance. Taguchi uses a modified form of the quadratic loss function to demonstrate the need to consider the proximity to the target while assessing its quality. But this traditional quadratic loss function is inadequate to assessing the quality and quality improvement since different processes have different sets of economic consequences on the manufacturing, Thereby, a flexible approach to the development of the loss function needs to be desired. In this paper, we introduce an easily understood loss function, based on reflection of probability density function of the normal distribution. That is, the Reflected Normal Loss function can be adapted to an asymmetric loss as well as to a symmetric loss around the target. We propose that, instead of the process variation, a new capability index, CpI using the Reflected Normal Loss Function that can accurately reflect the losses associated with the process and a new capability index CpI Is compared with the classical indices as $C_{p}$ , $C_{pk}$, $C_{pm}$ and $C_{pm}$ $^{+}$.>.+/./.