• Geophysics and Geophysical Exploration
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• v.11 no.2
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• pp.109-115
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• 2008

It is very important to estimate the physical properties of survey area and delineate the geological basement in marine site survey for the design of offshore structures. For the purpose of providing high quality data by means of engineering site survey, it is necessary to apply several survey techniques and carry out the integrated interpretation to each other. In this study, we applied single channel seismic reflection method and OBC (Ocean Bottom Cable) type seismic refraction method at shallow marine. We used a dual boomer-single channel streamer as a source-receiver in seismic reflection survey and airgun source-the developed OBC type streamer in seismic refraction survey. We made 24 channels OBC type streamer which has 4m channel interval and each channel is composed of single hydrophone and preamplifier. We tested the field applicability of the proposed method and applied the typical seismic data processing methods to the obtained reflection data in order to enhance the data quality and image resolution. In order to estimate the geological velocity distribution from refraction data, seismic refraction tomography technique was applied. Therefore, we could successfully perform time-depth conversion using the velocity information as an integrated interpretation. The proposed method could provide reliable geologic information such as sediment layer thickness and 3D basement depth map.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.7
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• pp.157-168
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• 2014

We propose an novel artificial visual attention model that is capable of automatic detection and segmentation of saliency region on natural images in this paper. The proposed model is based on human visual perceptions in biological vision and contains there are main contributions. Firstly, we propose a novel framework of artificial visual attention model based on the opponent process theory using intensity and color features, and an entropy filter is designed to perceive salient regions considering the amount of information from intensity and color feature channels. The entropy filter is able to detect and segment salient regions in high segmentation accuracy and precision. Lastly, we also propose an adaptive combination method to generate a final saliency map. This method estimates scores about intensity and color conspicuous maps from each perception model and combines the conspicuous maps with weight derived from scores. In evaluation of saliency map by ROC analysis, the AUC of proposed model as 0.9256 approximately improved 15% whereas the AUC of previous state-of-the-art models as 0.7824. And in evaluation of salient region segmentation, the F-beta of proposed model as 0.7325 approximately improved 22% whereas the F-beta of previous state-of-the-art models.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.7
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• pp.32-37
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• 2008

Satellite communication systems including the DVB-S2 (Digital Video Broadcasting - Satellite Version 2) system require operations under low signal-to-noise ratio (SNR) and large frequency offset values, and the initial frame synchronization process necessitates a robust correlation method. While a variety of conventional correlation structures exist for the initial synchronization, each method has different characteristics and performance in different channel environments. In this paper, we propose new correlation methods which exhibit enhanced performance in low SNR and large frequency offsets, and analyze their performance. The proposed methods use the magnitude sum and vector sum of extended differential correlation values, to maximize the correlation between the received signal and the synchronization sequence by using the spanned differential correlation result. The magnitude sum correlation method has better performance compared to conventional methods including the approximated ML (Maximum likelihood) method for SNR values below 4 dB with or without frequency offsets. The vector sum correlation method has improved performance over the magnitude sum method for channels with relatively small frequency offsets.

• Ecology and Resilient Infrastructure
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• v.2 no.2
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• pp.137-146
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• 2015

Lateral connectivity between a main channel and a former channel plays an integral role in maintaining ecological functions of stream-floodplain ecosystems. This study virtually restored the connectivity of the former channel, which is currently isolated by channelization, in the Mangyeong River, Korea. Fish habitat improvement after the connectivity restoration was evaluated using River2D, two-dimensional depth-averaged hydraulic modeling, depending on normal and flood flow conditions. Target fish species were crucian carp (Carassius auratus), which are known as lentic species, and pale chub (Zacco platypus), known as lotic species. The weighted usable area (WUA) of the two species was increased after the connectivity restoration: the two-way connection between the main and formal channels was more effective than the one-way connection. The result of the physical habitat simulation at a flood flow condition demonstrated an increased rate of the WUA than during a normal flow condition. In particular, the WUA of pale chub increased about four times on the two-way connectivity restoration. This result suggests that habitat availability of both lentic and lotic fish species will increase after a connectivity restoration, and a two-way connectivity restoration may be more effective. In addition, the restored formal channel would function as a shelter for fish during the flood season.

• Journal of Veterinary Clinics
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• v.19 no.3
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• pp.277-282
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• 2002

This study was designed to evaluate the effects of anesthetics on waveform of SEPs and to authorize possible anesthetic protocol for measurement of the somatosensory evoked potentials (SEPs). Thirteen anesthetic methods were used. The SEPs were recorded on two channels (between the 5th and 6th lumbar vertebra as the channel 1 and between the 11th and 12th thoracic vertebra as the channel 2) following stimulation of posterior tibial nerve. ID analyze SEPs wave, latency and conduction velocity were measured. Among thirteen anesthetic methods, standard SEPs waveforms were observed in dogs anesthetized with following six methods: Acepromazine + Thiepfntal Na + Isoflurane, Acepronazine + Propofol + Isoflurane, Diazepam + Xylazine, Xylazine + Ketamine, Acepromazine + Propofol infusion and Propofol infusion. Above six methods could be used with sufficient anesthetic depth. The differences of latency and conduction velocity among six groups were minimal compared to general waveform of SEPs. These results indicate that the six anesthetic methods can be used for recording SEPs in the dog. In particular, Diazepam + Xylazine and XylaBine + Ketamine as injectable anesthesia are considered more convenient than other four methods in veterinary medicine.

• Korean Journal of Microbiology
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• v.47 no.4
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• pp.295-301
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• 2011

Aquaporin is a water channel protein, which is classified as Major Intrinsic Protein (MIP), found in almost all organisms from bacteria to human. To date, more than 200 members of this family were identified. There are two major categories of MIP channels, orthodox aquaporins and aquaglyceroporins, which facilitate the diffusion across biological membranes of water or glycerol and other uncharged compounds, respectively. The full genome sequencing of various fungal species revealed 3 to 5 aquaporins in their genome. Although some functions of aquaporins found in yeast were characterized, however, no functional characteristics were studied so far in filamentous fungi, including Aspergillus sp. In this study, one orthodox aquaporin homolog gene, aqpA, and four aquaglyceroporin homologs, aqpB-E, in a model filamentous fungus Aspergillus nidulans were identified and the function of the aqpA gene was characterized. Knock-out of the aqpA gene didn't show any obvious phenotypic change under the osmotic stress, indicating that the function of the gene does not involved in the osmotic stress response or the function could be redundant. However, the mutant showed antifungal susceptibility resistance phenotype, suggesting that the function of the aqpA gene could be involved in sensing the antifungal substances rather than the osmotic stress response.

• Journal of the Korean Society for Nondestructive Testing
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• v.20 no.6
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• pp.538-544
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• 2000

A phased array ultrasonic nondestructive inspection system is being developed to obtain images of the interior of steel structures by modifying a medical ultrasound imaging system. The medical system consists of 64 individual transceiver channels that can drive 128 array elements. Several modifications of the system were required mainly due to the change of sound speed. It was necessary to fabricate array transducers for steel structure and to obtain A-scan signal that is necessary for the nondestructive testing. Boundary diffraction wave model was used for the prediction of radiation beam field from array transducers, which provided guidelines to design array transducers. And a RF data acquisition board was fabricated for the A-scan signal acquisition along a selected un line within an image. For the proper beam forming in the transmission and reception for steel structure, delay time was controlled. To demonstrate the performance of the developed system and fabricated transducers, images of artificial specimens and A-scan signals for selected scan lines were obtained in a real time fashion.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.35 no.4
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• pp.134-143
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• 2017

It has been 15 years since Jeju Island first was designated as one of UNESCO Biosphere Reserve areas. Jeju currently holds 5 UNESCO designations and the UNFAO Globally Important Agricultural Heritage (GIAHS). The 5 UNESCO global heritages that Jeju honors are the World Natural Heritage, Biosphere Reserve, Global Geoparks Network, Chilmeoridanggut Intangible Cultural Heritage (ICH) and JejuHaenyeo ICH. The UNFAO GIAHS that Jeju honors is Jeju Batdam Agricultural Heritage System. Those global titles are highly valued and recognized for environmental preservation and those global designations have attracted more visitors to the island. It is essential to see if Jeju global level heritages are recognized as they deserve attentions from home and abroad yet no holistic analysis on those 6 global level designations as a whole has been progressed to see the perception level among residents and visitors. The study aims to see the perception level of Jeju global Heritages, impact of global recognitions and the channels of the perception level. UNESCO World Natural Heritage and Haenyeo ICH have showed the highest perception level due to designation process and the amount of promotion by the managing division of Jeju municipality. The routine survey as per the result of the study regarding the perception level of those global designations could benefit Jeju tourism direction and help to preserve the island and culture.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.1
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• pp.379-384
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• 2021

Despite the numerous graduates being produced in practical music and history, which have not been shorter than 30 years, the employment of students remains an unsolvable task. Most graduates are employed by private institutes as music instructors or got involved in band activities, which are non-regular work and not stable. The rapid development of K-pop along with national strength has changed our lives as well. As a result, the cultural and artistic fields, which were previously recognized only as luxury, have rapidly become popular. In the form of learning, internalized and experiencing, not just watching has a huge impact on improving the quality of our lives. This is reflected in national policies including the operation of cultural arts, education programs in elementary, middle, and high schools, and art programs designed to improve the welfare of residents at local community centers. It is time to expand its job-horizon to the relevant fields, and thus focus on promoting programs related to obtaining certificates to help our students find jobs. In addition, the government should create a course for music teacher certification in the field of practical music that differs from the current music teacher certification of secondary schools. It is very urgent to establish the teaching course in four-year universities or graduate schools of practical music education.

• Natural Product Sciences
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• v.27 no.2
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• pp.86-98
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• 2021

This study was designed to characterize the effect of ginsenoside-Rg2 (Rg2), one of panaxatriol saponins isolated from Korean ginseng root, on the release of catecholamines (CA) in the perfused model of the rat adrenal medulla, and also to establish its mechanism of action. Rg2 (3~30 µM), administered into an adrenal vein for 90 min, depressed acetylcholine (ACh)-induced CA secretion in a dose- and time-dependent manner. Rg2 also time-dependently inhibited the CA secretion induced by 3-(m-chloro-phenyl-carbamoyl-oxy)-2-butynyltrimethyl ammonium chloride (McN-A-343), 1.1-dimethyl-4-phenyl piperazinium iodide (DMPP), and angiotensin II (Ang II). Also, during perfusion of Rg2, the CA secretion induced by high K⁺, veratridine, cyclopiazonic acid, methyl-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoro-methyl-phenyl)-pyridine-5-carboxylate (Bay-K-8644) depressed, respectively. In the simultaneous presence of Rg2 and N^ω-nitro-L-arginine methyl ester hydrochloride ʟ-NAME), the CA secretion induced by ACh, Ang II, Bay-K-8644 and veratridine was restored nearly to the extent of their corresponding control level, respectively, compared to those of inhibitory effects of Rg2-treatment alone. Virtually, NO release in adrenal medulla following perfusion of Rg2 was significantly enhanced in comparison to the corresponding spontaneous release. Also, in the coexistence of Rg2 and fimasartan, ACh-induced CA secretion was markedly diminished compared to the inhibitory effect of fimasartan-treated alone. Collectively, these results demonstrated that Rg2 suppressed the CA secretion induced by activation of cholinergic as well as angiotensinergic receptors from the perfused model of the rat adrenal gland. This Rg2-induced inhibitory effect seems to be exerted by reducing both influx of Na⁺ and Ca²⁺ through their ionic channels into the adrenomedullary cells as well as by suppressing Ca²⁺ release from the cytoplasmic calcium store, at least through the elevated NO release by activation of NO synthase, which is associated to the blockade of neuronal cholinergic and AT₁-receptors. Based on these results, the ingestion of Rg2 may be helpful to alleviate or prevent the cardiovascular diseases, via reduction of CA release in adrenal medulla and consequent decreased CA level in circulation.