• Journal of Korean Society of Industrial and Systems Engineering
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• v.24 no.68
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• pp.31-36
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• 2001

Prior to the Independent Visual Background(IVB) luminance control experiment, we studied that IVB could reduce the simulator sickness depending on subject＇s knowledge about the IVB (expectation group) or non-IVB (no expectation group). As results of experiments from 12 subjects, expectation group＇s RSSQ scores were similar, no matter IVB was present or not. However, non-expectation group＇s RSSQ scores were lower when the IVB were present. The result from this experiment confirms the findings of Duh (2001), that an IVB may alleviate SS. However this effect was found only at the expectation group. Failure to replicate Duh＇s results could be due to several factors, such as individual differences in response to the IVB and the low number of subjects (n=6) in the no expectation group.

• Journal of Information Processing Systems
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• v.13 no.1
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• pp.114-127
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• 2017

This paper proposes a color image coding algorithm based on shape-adaptive all phase biorthogonal transform (SA-APBT). This algorithm is implemented through four procedures: color space conversion, image segmentation, shape coding, and texture coding. Region-of-interest (ROI) and background area are obtained by image segmentation. Shape coding uses chain code. The texture coding of the ROI is prior to the background area. SA-APBT and uniform quantization are adopted in texture coding. Compared with the color image coding algorithm based on shape-adaptive discrete cosine transform (SA-DCT) at the same bit rates, experimental results on test color images reveal that the objective quality and subjective effects of the reconstructed images using the proposed algorithm are better, especially at low bit rates. Moreover, the complexity of the proposed algorithm is reduced because of uniform quantization.

• Particle and aerosol research
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• v.7 no.4
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• pp.113-121
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• 2011

The aerosol nanoparticles are suspected to be exposed to workers in nanomaterial manufacturing facilities. However, the exposure assessment method has not been established. One of important issues is to characterize background level of nanoparticles in workplaces. In this study, intensive aerosol measurements were made at a $TiO_2$ manufacturing laboratory for five consecutive days in May of 2010. The $TiO_2$ nanoparticles were manufactured by the thermal-condensation process in a heated tube furnace. The particle number size distribution was measured using a scanning mobility particle sizer every 5 min, in order to detect particles ranging from 14.5 to 664 nm in diameter. Total particle number concentration shows a severe diurnal variation irrespective of manufacturing process, which was governed by nanoparticles smaller than 50 nm in diameter. During the background monitoring periods, significant peak concentrations were observed between 2 p.m. and 3 p.m. due to the infiltration of secondary aerosol particles formed by photochemical smog. Although significant increase in nanoparticle concentration was also observed during the manufacturing process twice among three times, these particle peak concentrations were lower than those observed during the background measurement. It is suggested that the investigation of background particle contamination is needed prior to conducting main exposure assessment in nanomaterial manufacturing workplaces or laboratories.

• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.301-308
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• 2002

As part of perfluorocarbon (PFC) tracer release experiment conducted at the western coastal area of Korea in February 2001, the background concentration level of perfluorocarbons (PFCs) in the atmosphere was determined by gas chromatography with electron capture detector. Prior to the PFC tracer release experiment in the field, air samples were collected using active samplers and the background concentrations of PFCs were determined. The concentrations of perfluoromethylcyclohexane ($C_7F_{14}$, PMCH) in the western coastal area of Korea were in the range of 5.8-8.7 fL/L. The mean concentration of the PMCH in the region exhibited no significant spatial and temporal variations. This concentration level is somewhat higher and has larger standard deviation than those of studies previously conducted in USA and Europe on the background concentration levels of PFCs. Because the background concentration of PMCH in Korea is still very low and consistent temporally and spatially, the PMCH tracer can be used suitably for the studies of long-range atmospheric transport.

• Journal of Sensor Science and Technology
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• v.22 no.6
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• pp.410-414
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• 2013

As one of the effective methods for researching the objective tinnitus detection, the GPIAS (Gap Pre-pulse Inhibition of Acoustic Startle) measurement has been used to verify the existence of animal tinnitus objectively. The level and pattern of the background sound presented prior to a startle pulse are closely related with the GPIAS results. But the effect of the starting point of the background sound on animal startle responses has not been reported yet. In this paper, we present the implementation of a GPIAS measurement system based on an unconstrained enclosure to avoid animals' excessive constraint stress and deal with the animals' growth. After the performance of our implemented system has been tested through the animal experiment using 4 SD-rats, the effect of starting point of stimulus background sound on the startle response has been studied by the use of our implemented system. Through the results, it is verified that our system can measure the inhibition of animal startle responses due the gap pre-pulse for GPIAS calculation and the background sound starting point does not significantly effect on the startle response and the GPIAS values if the background sound continues for more than 300msec before a gap pre-pulse is presented.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.2
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• pp.115-122
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• 2016

The classical statistical approach using test data samples to estimate true value of Random Variables by calculating mean and variation (standard deviation or coefficient of variation) of samples is very useful to understand the existing condition of the structure. But with this classical approach, our prior knowledge through educational background and professional experience cannot provide any benefit to make decisions by the structural engineers. This paper shows the role of Bayesian methodology by providing chance of using valuable prior knowledge to come up with more accurate estimation of structural condition. This paper also shows how important it is to have a proper prior estimate of Random Variables and corresponding confidence level through gathering and studying more relevant information.

• Journal of Fashion Business
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• v.24 no.4
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• pp.19-29
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• 2020

The purpose of this study was to investigate Renaissance wall-covering fabrics through Flemish paintings, that provides the details of the origin and development of background of modern wallcovering. The methods of the study are as follows. First, the background of textile development of Flanders in the 14^th to 16^th centuries were examined through a prior study. Second, the shape and use of wallcoverings in paintings painted during that time were analyzed and the process of changing to modern forms was studied. The residential environment with many stone buildings in relatively humid and cold weather created a need for decorative fabrics. Back then, the wool and flax fabric were not allowed to be worn on the body, so the materials were used for the development of interior fabrics. The characteristics of wall covering in Flemish paint can be summarized with movable, allegory, and decoration. Movable stems from the arrival of the emerging aristocrats of Flanders, who had enormous commercial trade and carried decorative fabrics; the mobility has become an allegory in reality as the royal and aristocratic use of wall-decorated fabrics is the symbol of authority. In addition, unlike Italy, where silk was procured from the East, fabrics manufactured using flax and wool were not suitable for clothing in terms of religion and practicality and were used to decorate walls.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.3
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• pp.422-428
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• 2008

In this paper, we propose the robust object detection algorithm with spatial gradient information. To do this, first, we eliminate error values that appear due to complex environment and various illumination change by using prior methods based on hue and intensity from the input video and background. Visible shadows are eliminated from the foreground by using an RGB color model and a qualified RGB color model. And unnecessary values are eliminated by using the HSI color model. The background is removed completely from the foreground leaving a silhouette to be restored using spatial gradient and HSI color model. Finally, we validate the applicability of the proposed method using various indoor and outdoor conditions in a complex environments.

• Journal of the Institute of Convergence Signal Processing
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• v.12 no.1
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• pp.7-12
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• 2011

In this paper, we propose the technique detecting interest object region effectively in the images from periscope of submarine based on self-generated template. First, we extract the sea-sky line, and divide it into sky and sea area from background region based on the sea-sky line. In each divided background region, the blocks which can be represented in each background region are set as a reference template. After dividing an image into several same size of blocks, we apply multi template matching to the divided search blocks and histogram template to divide the image into object region and background region. Proposed algorithm is adapted to various images in which objects exist in the background of sea and sky. We verified that proposed algorithm performed properly without given informmed prby prior learning.ropso, regardless of the slope of sea-sky line and the locmed p of object based on sea-sky line, we verified that the objects region was segmented effectively from the input image.

• Journal of Ginseng Research
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• v.38 no.2
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• pp.106-115
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• 2014

Background: Gut microbiota is regarded as one of the major factors involved in the control of body weight. The antiobesity effects of ginseng and its main constituents have been demonstrated, but the effects on gut microbiota are still unknown. Methods: To investigate the effect of ginseng on gut microbiota, 10 obese middle-aged Korean women took Panax ginseng extracts for 8 wk and assessment of body composition parameters, metabolic biomarkers, and gut microbiota composition was performed using 16S rRNA gene-based pyrosequencing at baseline and at 8 wk. Significant changes were observed in body weight and body mass index; however, slight changes were observed in gut microbiota. We divided the participants into two groups, the effective and the ineffective weight loss groups, depending on weight loss effect, in order to determine whether the antiobesity effect was influenced by the composition of gut microbiota, and the composition of gut microbiota was compared between the two groups. Results: Prior to ginseng intake, significant differences of gut microbiota were observed between both at phyla and genera and the gut microbiota of the effective and ineffective weight loss groups was segregated on a principal coordinate analysis plot. Conclusion: Results of this study indicate that ginseng exerted a weight loss effect and slight effects on gut microbiota in all participants. In addition, its antiobesity effects differed depending on the composition of gut microbiota prior to ginseng intake.