• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.5
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• pp.481-486
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• 2012

We discuss the design, fabrication, and testing of a large-displacement electromagnetic actuator with the meander springs partially exposed to a magnetic field. We compared two prototypes: a prototype (F) of the conventional actuator with the meander springs fully exposed to a magnetic field and a prototype (P) of the proposed actuator with the meander springs partially exposed to a magnetic field. For a 5 Hz square input current varying from 10.40 mA, P showed an increase of $16.9{\pm}1.2%$ in the amplitude, which was greater than the increase in the case of F. Thus, we experimentally demonstrated the large-displacement actuation performance of the proposed actuator in a small volume and at low currents (below 40 mA). The proposed electromagnetic actuator can be used for low-power and large-displacement manipulation of optical switches and optical choppers.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.12 s.105
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• pp.1378-1388
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• 2005

Spatial control of sound is essential to deliver better sound to the listener's position in space. As it can be experienced in many listening environments. the quality of sound can not be manifested over every Position in a hall. This motivates us to control sound in a region we select. The primary focus of the developed method has to do with the brightness and contrast of acoustic image in space. In particular, the acoustic brightness control seeks a way to increase loudness of sound over a chosen area, and the contrast control aims to enhance loudness difference between two neighboring regions. This enables us to make two different kinds of zone - the zone of quiet and the zone of loud sound - at the same time. The other perspective of this study is on the direction of sound. It is shown that we can control the direction of perceived sound source by focusing acoustic energy in wavenumber domain. To begin with, the proposed approaches are formulated for pure-tone case. Then the control methods are extended to a more general case, where the excitation signal has broadband spectrum. In order to control the broadband signal in time domain, an inverse filter design problem is defined and solved in frequency domain. Numerical and experimental results obtained in various conditions certainly validate that the acoustic brightness, acoustic contrast, direction of wave front can be manipulated for some finite region in space and time.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.2-2
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• 2011

Single-walled carbon nanotubes (SWNTs) have been considered as a promising candidate for nextgeneration electronics due to its extraordinary electrical properties associated with one-dimensional structure. Since diversity in electronic structure depends on geometrical features, the major concern has been focused on obtaining the diameter, chirality, and density controlled SWNTs. Despite huge efforts, the controlled synthesis of SWNTs has not been achieved. There have been various approaches to synthesize controlled SWNTs by preparation of homogeneously sized catalyst because the SWNTs diameter highly depends on catalyst nanoparticles size. In this study, geometrically controlled SWNTs were synthesized using designed catalytic layers: (a) morphologically modified Al2O3 supporting layer (Fe/Al2O3/Si), (b) Mo capping layer (Mo/Fe/Al/Si), and (c) heat-driven diffusion and subsequent evaporation process of Fe catalytic nanoparticles (Al2O3/Fe/Al2O3/Si). These results clearly revealed that (a) the grain diameter and RMS roughness of Al2O3 supporting layer play a key role as a diffusion barrier for obtaining Fe nanoparticles with a uniform and small size, (b) a density and diameter of SWNTs can be simultaneously controlled by adjusting a thickness of Mo capping layer on Fe catalytic layer, and (c) SWNTs diameter was successfully controlled within a few A scale even with its fine distribution. This precise control results in bandgap manipulation of the semiconducting SWNTs, determined by direct comparison of Raman spectra and theory of extended tight binding Kataura plot. We suggest that these results provide a simple and possible way for the direct growth of diameter, density, and bandgap controlled SWNTs by precise controlling the formation of catalytic films, which will be in demand for future electronic applications.

• 한국공간정보시스템학회:학술대회논문집
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• 2000.06a
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• pp.93-105
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• 2000

GIS is a powerful toolbox in managing spatial data associated with attribute data. However GIS is short of spatial analysis function and graphic user interface(GUI) function in dealing with dynamic planning problems. Decision Support Systems(DSS) make up for the shortage of GIS by providing GUI function, modeling function and database function. Spatial Decision Support Systems(SDSS), a new kind of DSS, incorporate display function, basic spatial analysis function and manipulation function of spatial data and attribute data of GIS and GUI function, modeling function and database function of DSS in dealing with spatial planning problems. Planning Support Systems(PSS) add more advanced spatial analysis function and intertemporal function to the functions of SDSS. This study focuses on the modeling of a PSS for capacity expansion of water-distribution network depending upon land use planning by using GIS, value engineering(VE) and life cycle costing(LCC). The PSS shows a guideline about the investment of water-distribution networks related to urban growth management through generating certain numbers of dynamic alternatives to supply the amount of water caused by land use planning.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.32 no.3
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• pp.191-204
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• 2014

In recent years, multi-camera systems have been recognized as an affordable alternative for the collection of 3D spatial data from physical surfaces. The collected data can be applied for different mapping(e.g., mobile mapping and mapping inaccessible locations)or metrology applications (e.g., industrial, biomedical, and architectural). In order to fully exploit the potential accuracy of these systems and ensure successful manipulation of the involved cameras, a careful system calibration should be performed prior to the data collection procedure. The calibration of a multi-camera system is accomplished when the individual cameras are calibrated and the geometric relationships among the different system components are defined. In this paper, a new single-step approach is introduced for the calibration of a multi-camera system (i.e., individual camera calibration and estimation of the lever-arm and boresight angles among the system components). In this approach, one of the cameras is set as the reference camera and the system mounting parameters are defined relative to that reference camera. The proposed approach is easy to implement and computationally efficient. The major advantage of this method, when compared to available multi-camera system calibration approaches, is the flexibility of being applied for either directly or indirectly geo-referenced multi-camera systems. The feasibility of the proposed approach is verified through experimental results using real data collected by a newly-developed indirectly geo-referenced multi-camera system.

• Journal of Chest Surgery
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• v.46 no.4
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• pp.265-273
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• 2013

Background: The safety and efficacy of arterial composite grafts for total arterial revascularization have been demonstrated. The saphenous vein (SV) is a widely used graft because of its accessibility, sufficient length, and ease of manipulation. Our aim was to compare mid-term outcomes of saphenous vein Y-grafts with radial artery Y-grafts joined by anastomosis to the left internal thoracic artery. Materials and Methods: Records of off-pump coronary artery bypass grafting with composite Y-grafts based on the left internal thoracic artery technique in 552 patients were analyzed retrospectively. After propensity score matching, 79 radial arterial (RA) composite grafts (RA group) and 79 saphenous vein composite grafts (SV group) were compared. The duration of mean follow-up was $24.6{\pm}14.6$ months (range, 1 to 55 months). Results: There were no differences in surgical mortality, all-cause mortality, or morbidity among the groups. Rates of 4-year survival were 91.7% and 96.3% in the RA and SV groups, respectively (p=0.519). The coronary reintervention-free survival rate and freedom from major adverse cardiovascular or cerebrovascular events were similar in the two groups (p=0.685, p=0.564). Conclusion: Construction of composite Y-grafts using the radial artery or saphenous vein showed similar mid-term results. Long-term follow-up and randomized trials will be needed to confirm our present conclusions.

• Journal of Animal Science and Technology
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• v.58 no.6
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• pp.22.1-22.15
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• 2016

Background: Dietary manipulation is a common practice to mitigate gaseous emission from livestock production facilities, and the variation of fat level in the diet has shown great influence on ruminal volatile fatty acids (VFA) and enteric methane generation. The changes in dietary fat levels influence rumen chemistry that could modify manure nutrient composition along with odor and gaseous emissions from manure management facilities. Methods: A field experiment was carried out on beef cattle feedlots to investigate the effect of four levels of dietary fat concentrations (3 to 5.5 %) on the manure composition and gaseous emissions (methane-$CH_4$, nitrous oxide-$N_2O$, carbon dioxide-$CO_2$ and hydrogen sulfide-$H_2S$) from the feedlot pen surface. The experiment was carried out over a 5-month period from June to October during North Dakota's summer-fall climatic condition. Air and manure sampling was conducted five times at a 20-30 day intervals. Results: Overall, this research indicated that fat levels in diet have no or little effect on the nutrient composition of manure and gaseous emission from the pens with cattle fed with different diet. Though significant variation of gaseous emission and manure composition were observed between different sampling periods, no effect of high fat diet was observed on manure composition and gaseous emission. Conclusions: It can be concluded that addition of fat to animal diet may not have any impact on gaseous emission and manure compositions.

• Journal of the Korean Society of Clothing and Textiles
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• v.16 no.3 s.43
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• pp.209-221
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• 1992

A standpoint art's style, present-day Western dress was establishing a systematic, theoritical value in sphere of fine art's meaning & it's expression on the modern fashion. For this reason, I selected Impressionism (a broad senes: be included Impressionism, Neo-Impressionism, Post-Impressionism) that was designated 'the revolution of color'. In the previous paper, 1 already discussed about the modern fashion under the influence of the color of Impressionism, from this study, Neo-Impressionism's techniques & it's influence on the modern fashion was investigated. The Impressionists had purposely used uneven brushwork & a vivid palette to transmit the intensity & immediacy of nature, whereas the Neo-Impressionists utilized methodically applied dots, a technique commonly described as Pointillism, to achieve their rationalist goal of eliminating the fugitive & the casual in order to seize a more fundamental reality. Of all them, Seurat had already become interested in the posible analogies between science, music & psychology on the on hand & art on the other, and scientist's books & articles offered a wealth of theoretical support. 1'articulary, it was corroborated that effects of sadness, calm, or happiness could be achieved through manipulation of color & design. The conclusions are as follow: 1. Through the modern fashion, a space between pattern & pattern was reflected unstable balances & harmonies, that, Neo-Impressionist emphasized the distinction between outdoor & subject, between elaborately clothed & nude figures, corresponded to modern fashion's pattern. 2. The modern fashion was presented a small border or band within the pattern itself which colors complemented those of the adjacent pictorial surface and mediated between the painted image & its enclosure.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.4
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• pp.1-14
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• 2015

A manipulation of zoysiagrass's lateral stems and soil-media; used for slope revegetation, is expected to facilitate the production of high-quality grass. To study the influences on the growth of zoysiagrass depending upon various soil-media conditions, two different types of soil are used. The results obtained - through investigation of its cover rates, leaf color and number - are summarized as follows. In mountain regions soil, there are no significant differences in growth and development of grass in treatments: zoysiagrass's lateral stems treatments with 1cm, 2cm, and 3cm soil-media and treatment with only seeding. Zoysiagrass, in most of the treatments, show about the same growth rates, and at the end, fair visual quality. Zoysiagrass's lateral stems treatments with 2cm, 3cm show slightly better growth, however, thickness of soil-media need not be more than 1cm to obtain an expected quality of lawn. In decomposed granite soil, there appears statistical significance in growth of the grass in treatments: zoysiagrass's lateral stems treatments with 1cm, 2cm, and 3cm soil-media and treatment with only seeding. The thicker the soil-media, the better the growth of grass, and that in treatment with seeding-only shows poor quality in general. And therefore, it is efficacious to plant in 3cm soil-media when quick formation of lawn is necessary; however, using 2cm soil-media is ultimately the most cost-efficient way of formation. But, when time allows - that is, more than three months - 1cm soil-media in decomposed granite soil is reasonable to formate just as effective lawn. And so when performing seeding, additional covering, fertilization or increasing the quantity of seed must be considered.

• Journal of Fashion Business
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• v.24 no.4
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• pp.85-98
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• 2020

The Internet of Things (IoT) shopping environment can provide benefits and risks to consumers, including shopping convenience and invasion of consumer rights, respectively. We experimentally tested whether exposure to information regarding the benefits and risks of IoT shopping would elicit changes to consumer perceptions of the importance of shopping convenience and rights to information, as well as shopping intention among young online shopping consumers. The participants (N=218) were randomly assigned into one of two experimental conditions. The control group was exposed to a news article and a video emphasizing the shopping convenience of the Amazon Dash Button service, while the experimental group was exposed to the same news article and video provided to the control group, along with a news article about the judgment of the Munich court that the Dash Button violates German consumer law. We found an interaction effect of experimental condition and time on changes to the perceived importance of shopping convenience and shopping intention. The changes to the perceived relative importance of shopping convenience to consumer rights to information from pre- to post-manipulation differed significantly between the two experimental groups. The results of this study emphasize the importance of providing information on both the benefits and risks of IoT shopping. This was the first experimental study to examine the possibility of the invasion of consumer rights to information in the IoT shopping environment. This study urges researchers, marketers, and policy makers to focus more on consumer rights to information in the newly coming IoT shopping environment.