• Progress in Medical Physics
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• v.14 no.3
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• pp.203-210
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• 2003

PET (positron emission tomography) permits the investigation of physiological and biochemical processes in vivo. The accuracy of quantifying PET data is affected by its finite spatial resolution, which causes partial volume effects. In this study, we developed a method for partial volume correction using Hoffman phantom PET and MR data, and applied various FWHM (full width at half maximum) levels. We also applied this method to PET images of normal controls and tested for the possibility of clinical application. $^{18}$ F-PET Hoffman phantom images were co-registered to MR slices. The gray matter and white matter regions were then segmented into binary images. Each binary image was convolved by 4, 8, 12, 16 mm FWHM levels. These convolved images of gray and white matter were merged corresponding to the same level of FWHM. The original PET images were then divided by the convolved binary images voxel-by-voxel. These corrected PET images were multiplied by binary images. The corrected PET images were evaluated by analyzing regions of interests, which were drawn on the gray and white matter regions of the original MR image slices. We calculated the ratio of white to gray matter. We also applied this method to the PET images of normal controls. On analyzing the corrected PET images of Hoffman phantom, the ratios of the corrected images increased more than that of the uncorrected images. With the normal controls, the ratio of the corrected images increased more than that of the uncorrected images. The ratio increase of the corrected PET images was lower than that of the corrected phantom PET images. In conclusion, the method developed for partial volume correction in PET data may be clinically applied, although further study may be required for optimal correction.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.3
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• pp.147-166
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• 2023

Seed color is controlled by several genes and is a key trait in determining the metabolite content and biological activities of legume genotypes. In this study, 296 adzuki bean accessions, including 159 grey, 99 red, and 38 white adzuki beans, were grown in Korea. Variations in total phenolic content (TPC), total saponin content (TSC), DPPH^• scavenging activity, ABTS^•+ scavenging activity, and ferric reducing antioxidant power (FRAP) were assessed and were reported to be in the ranges of 1.52-8.24 mg GAE/g, 14.36-114.22 mg DE/g, 0.23-12.84 mg AAE/g, 1.05-17.66 mg TE/g, and 0.59-13.14 mg AAE/g, respectively, with a wide variation across adzuki beans. Except for DPPH^• scavenging activity, the average values declined in the order gray > red > white adzuki beans, each demonstrating a significant variation (p < 0.05). White adzuki beans, which showed low metabolite content and antioxidant activity, were clearly separated from the gray and red genotypes using principal component and hierarchical cluster analyses. Moreover, TPC, TSC, and antioxidant activities were strongly correlated, regardless of seed color. Overall, the diversity of the TPC, TSC, and antioxidant activity in a broad population of adzuki bean genotypes was determined. Furthermore, this study found that seed color variation in adzuki beans had a significant effect on the metabolite content and antioxidant activity. Superior accessions with high levels of TPC, TSC, and antioxidant activity were also discovered and could be used for functional plant breeding and human consumption. The findings of this study may be useful for understanding the relationship between seed coat color and metabolite concentration in adzuki beans, paving the way for molecular-level analyses.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.1
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• pp.12-17
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• 2010

Wild and cultured fish including olive flounder, sea bass, rock bream, yellowtail, gray mullet, gizzard shad, black rockfish, red seabream and squid were collected from a fish market located on the coast of Korea, and the antibiotic content of their muscle was investigated. Tetracycline group antibiotics were not detected in the 108 individuals of 9 species of wild fish. However, oxytetracycline (OTC) and tetracycline(TC) were detected in some samples of the 111 individuals in 7 cultured live fish species. The detected ranges of OTC and TC were ND~ 0.06 and ND~ 0.03, respectively. Five different fluoroquinolone antibiotics were also tested for, but were not detected in the wild fish species. Only small amount of criprofloxacin(ND~0.029 mg/kg) were detected in a few cultured fish samples. Oxolinic acid was not detected in either wild and cultured fish samples. Results showed that even very low levels of antibiotics could be detected by the testing methods used. Antibiotics were identified in a few fish samples but levels were far below the maximum allowable limits of the Korean Food Code, and the safety of fish being sold in markets, with regard to antibiotic levels, was confirmed.

• The Korean Journal of Physiology and Pharmacology
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• v.14 no.6
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• pp.413-417
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• 2010

To understand the function of edges in perception of moving objects, we defined four questions to answer. Is the focus point in visual motion detection of a moving object: (1) the body or the edge of the object, (2) the leading edge or trailing edge of the object, (3) different in scotopic, mesopic and photopic luminance levels, or (4) different for colored objects? We measured the Optomotor Response (OMR) and Edge Triggering Response (ETR) of goldfish. We used a square and sine wave patterns with black and red stripes and a square wave pattern with black and grey stripes to generate OMR's and ETR's in the goldfish. When we used black and red stripes, the black leading edges stimulated an ETR under scotopic conditions, red leading edges stimulated an ETR under photopic conditions, and both black and red leading edges stimulated an ETR under mesopic luminance levels. For black and gray stripes, only black leading edges stimulated an ETR in all three light illumination levels. We observed less OMR and ETR results using the sine wave pattern compared to using the square wave pattern. From these results, we deduced that the goldfish tend to prefer tracking the leading edge of the pattern. The goldfish can also detect the color of the moving pattern under photopic luminance conditions. We decided that ETR is an intriguing factor in OMR, and is suitable as a method of behavioral measurement in visual system research.

• Journal of Acupuncture Research
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• v.27 no.5
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• pp.13-24
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• 2010

Objectives : This study was designed to investigate the effects of bee venom acupuncture at Shinsu($BL_{23}$) and Daejangsu($BL_{25}$) on neuropathic pain induced by tibial and sural nerve injury in rats. Methods : Neuropathic pain model was made by partial resection of tibial and sural nerve. Three weeks after the neuropathic surgery, bee venom acupuncture was firstly injected at $BL_{23}$ and $BL_{25}$, then we measured withdrawal responses induced by von Frey filament and acetone stimulation. Bee venom acupunctures were injected 6times on every 2days. Measurement of withdrawal responses were conducted on the same days. After bee venom acupuncture injection, expression levels of c-Fos, nocieptin and KOR-3 were observed through using immunohistochemistry. Results : In this experiment, bee venom acupunctures at $BL_{23}$ and $BL_{25}$ decreased levels of withdrawal responses induced by von Frey filament and acetone stimulation respectively. In addtion, expression levels of c-Fos, nociceptin and KOR-3 in central gray part of brain in rats were decreased by bee venom acupuncture. Conclusions : These results imply that bee venom acupuncture was useful to treat patients with neuropathic pain, and related mechanisms were involved in opioid and their receptors such as nociceptin and KOR-3.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.45 no.2
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• pp.10-20
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• 2008

Generally, to acquire an HDR image, many images that cover the entire dynamic range of the scene with different exposure times are required, then these images are fused into one HDR image. This paper proposes an efficient method for the HDR image acquisition with small number of images. First, we estimated scenic dynamic range using two images with different exposure times. These two images contain the upper and lower limit of the scenic dynamic range. Independently of the scene, according to varied exposure times, similar characteristics for both the maximum gray levels in images that include the upper limit and the minimum gray levels in images that include the lower limit are identified. After modeling these characteristics, the scenic dynamic range is estimated using the modeling results. This estimated scenic dynamic range is then used to select the proper exposure times for the acquisition of an HDR image. We selected only three proper exposure times because entire dynamic range of the cameras could be covered by three dynamic range of the cameras with different exposure times. To evaluate the error of the HDR image, experiments using virtual digital camera images were carried out. For several test images, the error of the HDR image using proposed method was comparable to that of the HDR image which utilize more than ten images for the HDR image acquisition.

• Agricultural and Biosystems Engineering
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• v.4 no.1
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• pp.8-15
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• 2003

In Korea, quality evaluation of dried oak mushrooms are done first by classifying them into more than 10 different categories based on the state of opening of the cap, surface pattern, and colors. And mushrooms of each category are further classified into 3 or 4 groups based on its shape and size, resulting into total 30 to 40 different grades. Quality evaluation and sorting based on the external visual features are usually done manually. Since visual features of mushroom affecting quality grades are distributed over the entire surface of the mushroom, both front (cap) and back (stem and gill) surfaces should be inspected thoroughly. In fact, it is almost impossible for human to inspect every mushroom, especially when they are fed continuously via conveyor. In this paper, considering real time on-line system implementation, image processing algorithms utilizing artificial neural network have been developed for the quality grading of a mushroom. The neural network based image processing utilized the raw gray value image of fed mushrooms captured by the camera without any complex image processing such as feature enhancement and extraction to identify the feeding state and to grade the quality of a mushroom. Developed algorithms were implemented to the prototype on-line grading and sorting system. The prototype was developed to simplify the system requirement and the overall mechanism. The system was composed of automatic devices for mushroom feeding and handling, a set of computer vision system with lighting chamber, one chip microprocessor based controller, and pneumatic actuators. The proposed grading scheme was tested using the prototype. Network training for the feeding state recognition and grading was done using static images. 200 samples (20 grade levels and 10 per each grade) were used for training. 300 samples (20 grade levels and 15 per each grade) were used to validate the trained network. By changing orientation of each sample, 600 data sets were made for the test and the trained network showed around 91 % of the grading accuracy. Though image processing itself required approximately less than 0.3 second depending on a mushroom, because of the actuating device and control response, average 0.6 to 0.7 second was required for grading and sorting of a mushroom resulting into the processing capability of 5,000/hr to 6,000/hr.

• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.504-506
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• 1993

The Joint Photographic Experts Group (JPEG) standard was proposed by the International Standardization Organization (ISO/SC 29/WG 10) and the CCITT SG VIII as an international standard for digital continuous-tone still image compression. The JPEG standard has been widely accepted in electronic imaging, computer graphics, and multi-media applications, however, due to the lossy character of the JPEG compression its application in the field of medical imaging has been limited. In this paper, the JPEG standard was applied to a series of head sections of magnetic resonance (MR) images (256 gray levels, $256{\times}256$ size) and its performance was investigated. For this purpose, DCT-based sequential mode of the JPEG standard was implemented using the CL550 compression chip and progressive and lossless coding was implemented by software without additional hardware. From the experiment, it appears that the compression ratio of about 10 to 20 was obtained for the MR images without noticeable distortion. It is also noted that the error signal between the reconstructed image by the JPEG and the original image was nearly random noise without causing any special-pattern-related artifact. Although the coding efficiency of the progressive and hierarchical coding is identical to that of the sequential coding in compression ratio and SNR, it has useful features In fast search of patient Image from huge image data base and in remote diagnosis through slow public communication channel.

• BMB Reports
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• v.39 no.4
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• pp.400-405
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• 2006

A 16-month old boy was referred to our hospital for evaluation of recurrent generalized tonic clonic seizures. Metabolic evaluation revealed significant hyperammonemia ($1,112\;{\mu}g/dl$). Amino acid/acylcarnitine screening using tandem mass spectrometry showed markedly increased plasma levels of citrulline ($1,350\;{\mu}M/l$) with undetectable levels of arginine and arginosuccinic acid. Urinary excretion of citrulline was markedly increased ($38,617\;{\mu}M/g$ creatinine). Brain MRI findings showed diffuse high-signal intensity lesions, that involved gray and white matter in both frontal lobes and insula with edematous changes; these findings were consistent with the acute stage of citrullinemia (CTLN). Mutation analysis of the argininosuccinate synthetase (ASS) gene, in this patient, showed a Gly324Ser mutation in exon 13, and a 67-bp duplication mutation in exon 15 (c.1128-6_1188dup67). The patient was confirmed as having late-onset CTLN1 and treated with anticonvulsants, lactulose enema, protein restricted diet and arginine. Here we describe a case of late-onset CTLN1 in a patient by biochemical analyses and ASS gene mutation confirmation. This is the first report of a Korean patient with late-onset CTLN1 confirmed by ASS gene mutation identification.

• Journal of the Korean Society of Safety
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• v.28 no.4
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• pp.26-32
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• 2013

A digital image correlation(DIC) method is a whole-field measurement technique that acquires surface displacements and strains from images information which characterized a random speckle as intensity grey levels. Recently years, this DIC method is being developed and used increasingly in various research. In this study, we tried to apply to aluminum alloy(Al 6061-T6) using DIC method and strain gauge. DIC results demonstrated the usefulness and ability to determine a strain. The test specimen used in this study was an aluminum alloy(Al 6061-T6, thickness 1 mm). For a strain measurement, a strain gauge was attached at the center of a specimen. A specimen was lightly sprayed with a white paint and a black dot pattern was sprayed on its fully dried white surface to obtain a random speckle. The experimental apparatus used to perform the tensile test consisted of universal dynamic tester(5 kN; T.O. Co.) under displacement speed of 0.5, 1.0 and 3.0 mm/min. A Model 5100 B Scanner(V. Co.) used to obtain a strain. A CCD camera connected to a PC uses to record the images of the specimen surface. After acquisition, the images were transferred to PC where the DIC software was implemented. An acquired image was evaluated by the DIC program. DIC method for displacement and strain was suggests and it results show a good consistent remarkably. DIC results demonstrated the usefulness and ability to determine surface strain was better than by using classical measurements. The strain field measurement using a DIC is so useful that it can be applied to map strain distributions at a full area. DIC method can evaluate a strain change so it can predict a location of fracture. The findings of the investigation suggest that the DIC method is an efficient and reliable tool for full-field monitoring and detailed damage characterization of materials.