• Nuclear Medicine and Molecular Imaging
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• v.42 no.4
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• pp.267-274
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• 2008

Purpose: Transient neurological deterioration (TND) is one of the complications after extracranial-intracranial bypass surgery, and it has been assumed to be caused by postoperative transient hyperperfusion. This study was performed to evaluate the relationship between TND and preoperative and postoperative cerebral perfusion status on brain perfusion SPECT following superficial temporal artery - middle cerebral artery (STA-MCA) anastomosis surgery. Materials and Methods: A total of 60 STA-MCA anastomosis surgeries of 56 patients (mean age: $50{\pm}16$ yrs; M:F=29:27; atherosclerotic disease: 33, moyamoya disease: 27) which were done between September 2003 and July 2006 were enrolled. The resting cerebral perfusion and cerebral vascular reserve (CVR) after acetazolamide challenge were measured before and 10 days after surgery using 99mTc-ethylcysteinate dimer (ECD) SPECT. Moreover, the cerebral perfusion was measured on the third postoperative day. With the use of the statistical parametric mapping and probabilistic brain atlas, the counts for the middle cerebral artery (MCA) territory were calculated for each image, and statistical analyses were performed. Results: In 6 of 60 cases (10%), TND occurred after surgery. In all patients, the preoperative cerebral perfusion of affected MCA territory was significantly lower than that of contralateral side (p=0.002). The cerebral perfusion on the third and tenth day after surgery was significantly higher than preoperative cerebral perfusion (p=0.001, p=0.02). In TND patients, basal cerebral perfusion and CVR on preoperative SPECT were significantly lower than those of non-TND patients (p=0.01, p=0.05). Further, the increases in cerebral perfusion on the third day after surgery were significant higher than those in other patients (p=0.008). In patients with TND, the cerebral perfusion ratio of affected side to contralateral side on third postoperative day was significantly higher than that of other patients (p=0.002). However, there was no significant difference of the cerebral perfusion ratio on preoperative and tenth postoperative day between patients with TND and other patients. Conclusion: In patients with TND, relative and moderate hyperperfusion was observed in affected side after bypass surgery. These finding may help to understand the pathophysiology of TND.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.5
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• pp.680-687
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• 1999

To understand the role of shelf sediment in phosphorus biogeochemical cycle, we carried out sequential sediment extraction (SEDEX) of P and porewater analysis on 14 core samples collected in the South Sea of Korea, SEDEX classified P-pools into 5 phases and results are grouped into two categories: reactive P (loosely sorbed-P and Fe bound-P) and refractory P (detrital inorganic-p, authigenic mineral-P and organic-P). Total P concentrations are decreased with sediment depth in all samples as a result of dissolution to porewater. Reactive P comprises about $20\~50\%$ of total P, and iron bound-P is the major form consisting $70\~80\%$ of reactive P-pool. Iron bound-P decreases sharply with depth. Depth profiles of dissolved P concentration in porewater show mirror image of iron bound-P, revealing the role of FeOOH as a regulator of reactive P supply to overlying water column. Authigenic mineral-P consists less than $5\%$ of total P, thus removal of reactive P by converting into refractory P seems inefficient in shelf sediment. This implies that continental shelf sediment sequesters P temporarily rather than permanently. Results show local variation. Nakdong estuary receiving large amount of terrigenous input shows the highest concentration of total P and reactive P. Here iron oxyhydroxides at the surface sediment control the water column flux of P from sediment. Although total P content at the surface is comparable (500$\~$600 ${\mu}g{\cdot}g^{-1}$) between the South Sea and East China Sea, the former contains more iron bound-P and less derital inorganic-P than the latter. Reasons for the difference seem due in part to particle texture, and to biological productivity which depends roughly on the distance from land.

• Korean Journal of Remote Sensing
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• v.24 no.2
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• pp.189-194
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• 2008

Middle-infrared (MIR) spectral region between 3.0 and $5.0\;{\mu}m$ in wavelength is useful for observing high temperature events such as volcanic activities and forest fire. However, atmospheric effects and sun irradiance in day time has not been well studied for this MIR spectral band. The objectives of this basic study is to evaluate atmospheric effects and eventually to estimate surface temperature from a single channel MIR image, although a typical approach utilize split-window method using more than two channels. Several parameters are involved for the correction including various atmospheric data and sun-irradiance at the area of interest. To evaluate the effect of sun irradiance, MODIS MIR images acquired in day and night times were used for comparison. Atmospheric parameters were modeled by MODTRAN, and applied to a radiative transfer model for estimating the sea surface temperature. MODIS Sea Surface Temperature algorithm based upon multi-channel observation was performed in comparison with results from the radiative transfer model from a single channel. Temperature difference of the two methods was $0.89{\pm}0.54^{\circ}C$ and $1.25{\pm}0.41^{\circ}C$ from the day-time and night-time images, respectively. It is also shown that the emissivity effect has by more largely influenced on the estimated temperature than atmospheric effects. Although the test results encourage using a single channel MR observation, it must be noted that the results were obtained from water body not from land surface. Because emissivity greatly varies on land, it is very difficult to retrieval land surface temperature from a single channel MIR data.

• The Korean Journal of Nuclear Medicine Technology
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• v.23 no.2
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• pp.20-24
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• 2019

Purpose Molecular Breast Imaging (MBI) scan is used in nuclear medicine, for which $^{99m}Tc-sestaMIBI$ is administered by intravenous injection. However, the breast uptake rate of $^{99m}Tc-sestaMIBI$ is less than 1% of the total dose administered, relying on blood flow conditions of organs. The purpose of this study is to evaluate the impact of changes to body temperature on the uptake of $^{99m}Tc-sestaMIBI$ in breast tissue. Materials and Methods We investigated 30 breast cancer patients who performed more than one follow-up MBI scan. All scans were acquired by Discovery 750B (Genral Electric Healthcare, USA). $^{99m}Tc-sestaMIBI$ injected with 740 MBq (20 mCi), after 60 minutes, gained bilateral breast CC (CranioCaudal), MLO (Medio Lateral Oblique) View. The follow-up examination was then classified into 15 body temperature control group and 15 body temperature non-control group, and gained breast image in the same way as before. The breast uptake rate was analyzed in the MLO View of the opposite side of the lesion, and blind images were evaluated. Results The breast uptake rate increased by 30.31% in the body temperature control group and it was statistically significant(P<0.05), and 0.96% in the body temperature non-control group, and it was not statistically significant(P=0.955). There was a significant difference in the uptake rate between the body temperature control and the non-control group of P value of 0.01. Evaluation of blind images showed significant results in terms of the quality of the images. Conclusion Increased breast tissue uptake was observed when the subject was kept warm. When the body temperature was raised after injection, dilation of the peripheral blood vessels can be achieved. As a result, the blood flow became smooth and the breast uptake rate increased. In addition, an increase in breast tissue uptake will improve the quality of images.

• Journal of Science Education
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• v.43 no.1
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• pp.157-172
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• 2019

The purpose of this study is to analyze the influence of number of targets on common knowledge generation and brain activity during the common life science discovery task performance. In this study, 35 preliminary life science teachers participated. This study was intentionally made a block designed for EEG recording. EEGs were collected while subjects were performing common discovery tasks. The sLORETA method and the relative power spectrum analysis method were used to analyze the brain activity difference and the role of activated cortical and subcortical regions according to the degree of difficulty of common discovery task. As a result of the study, in the case of the Theta wave, the activity of the Theta wave was significantly decreased in the frontal lobe and increased in the occipital lobe when the difficult difficulty task was compared with the easy difficulty task. In the case of Alpha wave, the activity of Alpha decreased significantly in the frontal lobe when performing difficult task with difficulty. Beta wave activity decreased significantly in the frontal lobe, parietal lobe, and occipital lobe when performing difficult task. Finally, in the case of Gamma wave, activity of Gamma wave decreased in the frontal lobe and activity increased in the parietal lobe and temporal lobe when performing the difficult difficulty task compared to the task of easy difficulty. The level of difficulty of the commonality discovery task is determined by the cingulate gyrus, the cuneus, the lingual gyrus, the posterior cingulate, the precuneus, and the sub-gyral where it was shown to have an impact. Therefore, the difficulty of the commonality discovery task is the process of integrating the visual information extracted from the image and the location information, comparing the attributes of the objects, selecting the necessary information, visual work memory process of the selected information. It can be said to affect the process of perception.

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.343-355
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• 2022

This study investigated the consumption tendency and awareness of paprika in order to expand and promote the consumption of Capsicum annuum L. The research investigated the relationship of preference and loyalty based on emotional response of paprika according to the semantic differential scale. The survey was conducted from January to February 2022 using a random sampling method targeting 155 general people, and a total of 142 questionnaires were analyzed excluding 13 wrong answers. The nine items on the awareness of paprika showed to be consisted of three factors such as 'Food taste', 'Usability', and 'Economics' by factor analysis. Regarding to the awareness of paprika the positive answer that 'I think paprika is good for health' among the nine questions was the highest at 92.3%. In the preference aspect of shape, blocky type had the highest preference for the shape of paprika, followed by mini and conical types in order of preference (p < 0.001). As for color preference, yellow paprika was the most preferred, followed by orange, red, and green, showing statistical significance. The emotional response of paprika by paprika image showed a statistically significant difference in the four colors. The words such as 'bright', 'clean', and 'spirited' appeared as representative emotional vocabulary for paprika. Multiple regression analysis was performed to examine the effect of paprika on the three factors of awareness, preference, and loyalty due to the quality of life. As a result, the higher the paprika preference and quality of life, and the higher the taste and availability factors, the higher the paprika awareness and loyalty. As the variable that has the most influence on the loyalty of the survey respondents, preference was found to have the highest explanatory power at 43%. From these results, it was judged as a very important factor in the survey on the shape and color preference of paprika. Therefore, the recent increase in awareness that paprika is good for health is thought to act as a positive factor in revitalizing the domestic market and increasing consumption of paprika in the future. Also, among the three types of paprika, the yellow blunt type showed the highest preference. Therefore, in order to produce and promote this type of paprika, it is also important to increase the cultivation to suit the purchasing propensity of consumers.

• Korean Journal of Remote Sensing
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• v.38 no.6_1
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• pp.1445-1462
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• 2022

Compact Advanced Satellite 500-4 (CAS500-4), which is scheduled to be launched in 2025, is a mid-resolution satellite with a 5 m resolution developed for wide-area agriculture and forest observation. To utilize satellite images, it is important to establish a precision sensor model and establish accurate geometric information. Previous research reported that a precision sensor model could be automatically established through the process of matching ground control point (GCP) chips and satellite images. Therefore, to improve the geometric accuracy of satellite images, it is necessary to improve the GCP chip matching performance. This paper proposes an improved GCP chip matching scheme for improved precision sensor modeling of mid-resolution satellite images. When using high-resolution GCP chips for matching against mid-resolution satellite images, there are two major issues: handling the resolution difference between GCP chips and satellite images and finding the optimal quantity of GCP chips. To solve these issues, this study compared and analyzed chip matching performances according to various satellite image upsampling factors and various number of chips. RapidEye images with a resolution of 5m were used as mid-resolution satellite images. GCP chips were prepared from aerial orthographic images with a resolution of 0.25 m and satellite orthogonal images with a resolution of 0.5 m. Accuracy analysis was performed using manually extracted reference points. Experiment results show that upsampling factor of two and three significantly improved sensor model accuracy. They also show that the accuracy was maintained with reduced number of GCP chips of around 100. The results of the study confirmed the possibility of applying high-resolution GCP chips for automated precision sensor modeling of mid-resolution satellite images with improved accuracy. It is expected that the results of this study can be used to establish a precise sensor model for CAS500-4.

• Korean Journal of Remote Sensing
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• v.37 no.3
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• pp.449-461
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• 2021

Analysis Ready Data (ARD) for optical satellite images represents a pre-processed product by applying spectral characteristics and viewing parameters for each sensor. The atmospheric correction is one of the fundamental and complicated topics, which helps to produce Top-of-Atmosphere (TOA) and Top-of-Canopy (TOC) reflectance from multi-spectral image sets. Most remote sensing software provides algorithms or processing schemes dedicated to those corrections of the Landsat-8 OLI sensors. Furthermore, Google Earth Engine (GEE), provides direct access to Landsat reflectance products, USGS-based ARD (USGS-ARD), on the cloud environment. We implemented the Orfeo ToolBox (OTB) atmospheric correction extension, an open-source remote sensing software for manipulating and analyzing high-resolution satellite images. This is the first tool because OTB has not provided calibration modules for any Landsat sensors. Using this extension software, we conducted the absolute atmospheric correction on the Landsat-8 OLI images of Railroad Valley, United States (RVUS) to validate their reflectance products using reflectance data sets of RVUS in the RadCalNet portal. The results showed that the reflectance products using the OTB extension for Landsat revealed a difference by less than 5% compared to RadCalNet RVUS data. In addition, we performed a comparative analysis with reflectance products obtained from other open-source tools such as a QGIS semi-automatic classification plugin and SAGA, besides USGS-ARD products. The reflectance products by the OTB extension showed a high consistency to those of USGS-ARD within the acceptable level in the measurement data range of the RadCalNet RVUS, compared to those of the other two open-source tools. In this study, the verification of the atmospheric calibration processor in OTB extension was carried out, and it proved the application possibility for other satellite sensors in the Compact Advanced Satellite (CAS)-500 or new optical satellites.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.40 no.2
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• pp.24-33
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• 2022

The travel notes and nature poems found in historic literary men's works can be considered historical records related to scenic sites. Such travel notes and nature poems are based on the writers' personal characters, experiences, learning and etc. Such works clearly show the characters of each literature, information of the related objects and the writers' thoughts of the objects. This study, thus, looked into Euisang on Xīsāishān Mountain that could be the origin of Eobusa(漁父詞) loved and sung by Korean historic literary men, and found that the Korean and Chinese literary men's thoughts were shown through their ways to enjoy Xīsāishān Mountain and their Euisang on the mountain, which was different between the Korean and Chinese literary men depending on the geographical locations described in their poems. In detail, the study results are: 1. Such difference of the ways to enjoy Xīsāishān Mountain, the scenic site described in historic Korean and Chinese literary men's work is broadly classified into the ways to enjoy the scenic site by seeing it in person and the ways to enjoy it under the mental structure of speculation. 2. Xīsāishān Mountain in Wuxing is the background of Yújiāzi(漁家子) of the painting Zhāngzhìhé, is boasting its distinguished beautiful nature, and is the place where the Confucian Study of Hú(湖學) was originated. It is also the place known of its warmhearted climate. Therefore, Euisang on Xīsāishān Mountain under such beautiful and warmhearted circumstance are realized as the complete freedom and seclusion in Taoism and the satisfaction with the given environment and position in Confucianism. 3. Xīsāishān Mountain in Wǔchāng is a military strategic point with rugged mountain terrain and scenery that has been a historic ferocious battlefield and related with the loyal civil servant Qū Yuán. The Euisang on Xīsāishān Mountain in Wǔchāng, therefore, represents the nature scenery of a rugged fortress and patriotism of Confucianism. 4. The Korean literary men's way to enjoy Xīsāishān Mountain is Shinyu(神遊: spiritual travel), so that their Euisang is formed according to the direction of the writer's values. Especially it is noted that Korean Euisang on Xīsāishān Mountain is originally based on the painting Zhāngzhìhé that shows the complete free mood of Taoism; and the Euisang on Xīsāishān Mountain that came from the mindful image by the poet monk Qíjǐ of Tang dynasty and Kim Si-seup appears with such Buddhist ways to seek the truth as SakGongIlYeo(色空一如: Being full is essentially as same as being vacant) and GyeonSeongSeongBul(見性成佛: Everybody can become Buddha by enlightenment).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.1
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• pp.20-26
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• 2023

Fiber content in the storage roots of sweetpotato varies between different varieties. For examples, the high fiber content of certain types has a poor texture when steamed or roasted. This study was conducted to evaluate the optimal sieve mesh size for separating fibers, the chemical composition of fibers and differences in fiber content among different varieties. We found that the separated fiber content (dry weight) of mashed and steamed sweetpotato was higher after washing three times (143.3 mg/100 g) compared with that washed five times (128.4 mg/100 g). The Hogammi variety remained 85.9% of total fiber content at 10 mesh (2,000 ㎛) and 9.6% of total fiber content at 30 mesh (600 ㎛), and Jinyulmi remained 74.9 and 16.7% of total fiber content , respectively. Therefore, a 30 mesh sieve was considered the most suitable for fiber separation. Among the 10 studied cultivars, Jinhongmi showed the lowest amount of fiber (24.8 mg/100 g) and Hogammi had the highest amount (111.4 mg/100 g), which was 4.5 times larger than that of Jinhongmi. Cellulose, hemicellulose and lignin content of separated fibers showed no difference between the viscous-type Hogammi and powdery-type Jinyulmi varieties, with averages of 32.5, 22.3 and 29.6%, respectively. Correlation results using the Image J program showed a significant correlation between the distribution of the stained area and the fiber content (R = 0.74, p < 0.05). Staining distribution differed among varieties, suggesting that a simple fiber content test could be performed using the staining method on raw sweetpotato. These results provide useful information to help inform farmers on the fiber content of different sweetpotato varieties.