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Extraction of Muscle Areas from Ultrasonographic Images using Information of Fascia (근막 정보를 이용한 초음파 영상에서의 근육 영역 추출)

  • Kim, Kwang-Baek
    • Journal of Korea Multimedia Society
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    • v.11 no.9
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    • pp.1296-1301
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    • 2008
  • Ultrasonography constructs pictures of areas inside the body needs in diagnosis by bouncing high-enorgy sound waves(ultrasound) off internal tissues or organs. In constructing an ultrasonographic image, the weakness of bounding signals induces noises and detailed differences of brightness, so that having a difficulty in detecting and diagnosing with the naked eyes in the analysis of ultrasonogram. Especially, the difficulty is extended when diagnosing muscle areas by using ultrasonographic images in the musculoskeletal test. In this paper, we propose a novel image processing method that computationally extracts a muscle area from an ultrasonographic image to assist in diagnosis. An ultrasonographic image consists of areas corresponding to various tissues and internal organs. The proposed method, based on features of intensity distribution, morphology and size of each area, extracts areas of the fascia, the subcutaneous fat and other internal organs, and then extracts a muscle area enclosed by areas of the fascia. In the extraction of areas of the fascia, a series of image processing methods such as histogram stretching, multiple operation, binarization and area connection by labeling is applied. A muscle area is extracted by using features on relative position and morphology of areas for the fascia and muscle areas. The performance evaluation using real ultrasonographic images and specialists' analysis show that the proposed method is able to extract target areas being approximate to real muscle areas.

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Performance Improvement of Web Information Retrieval Using Sentence-Query Similarity (문장-질의 유사성을 이용한 웹 정보 검색의 성능 향상)

  • Park Eui-Kyu;Ra Dong-Yul;Jang Myung-Gil
    • Journal of KIISE:Software and Applications
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    • v.32 no.5
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    • pp.406-415
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    • 2005
  • Prosperity of Internet led to the web containing huge number of documents. Thus increasing importance is given to the web information retrieval technology that can provide users with documents that contain the right information they want. This paper proposes several techniques that are effective for the improvement of web information retrieval. Similarity between a document and the query is a major source of information exploited by conventional systems. However, we suggest a technique to make use of similarity between a sentence and the query. We introduce a technique to compute the approximate score of the sentence-query similarity even without a mature technology of natural language processing. It was shown that the amount of computation for this task is linear to the number of documents in the total collection, which implies that practical systems can make use of this technique. The next important technique proposed in this paper is to use stratification of documents in re-ranking the documents to output. It was shown that it can lead to significant improvement in performance. We furthermore showed that using hyper links, anchor texts, and titles can result in enhancement of performance. To justify the proposed techniques we developed a large scale web information retrieval system and used it for experiments.

LED Sensitive Light System Development by Brain-wave (LED감성조명 장치 개발을 통한 뇌파분석)

  • Choi, Keum-Yeon;Eo, Ik-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.1
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    • pp.61-66
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    • 2010
  • The purpose of this experiment is to analyze the basic status of brain. Which are consist of rest, attention and concentration, of the brain by measuring the temperature of color by changing RGB color after manufacturing LED-illumination stand. Basic status (rest, attention and concentration) of experimenter were measured temperature of colors having three difference temperature like as $2,300^{\circ}K$, $4,000^{\circ}K$ and $6,000^{\circ}K$. The results was shown that experimenter feels more comfortable and relaxation by decreasing the temperature of color. For example we can see the little increase of concentration index at $4,000^{\circ}K$ condition and we can estimate that right brain can be more activated at the $4,000^{\circ}K$ condition. But we can not find out any different at the $6,000^{\circ}K$ condition. Main cause of no difference from the color temperature was the similarity of color temperature under the general fluorescent lamp. And interface temperature of radiant heat design results LED and PCB was approximately 80 degrees to COMSOL Multiphysics, and changed until approximately 50 degrees until a floor plane of PCB, and verification as arranged chip LED to metal PCB, and it was possible, and a near radiant heat design was confirmed to an approximate value of, as a result, acid manufacture.

Upper Bounds for the Performance of Turbo-Like Codes and Low Density Parity Check Codes

  • Chung, Kyu-Hyuk;Heo, Jun
    • Journal of Communications and Networks
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    • v.10 no.1
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    • pp.5-9
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    • 2008
  • Researchers have investigated many upper bound techniques applicable to error probabilities on the maximum likelihood (ML) decoding performance of turbo-like codes and low density parity check (LDPC) codes in recent years for a long codeword block size. This is because it is trivial for a short codeword block size. Previous research efforts, such as the simple bound technique [20] recently proposed, developed upper bounds for LDPC codes and turbo-like codes using ensemble codes or the uniformly interleaved assumption. This assumption bounds the performance averaged over all ensemble codes or all interleavers. Another previous research effort [21] obtained the upper bound of turbo-like code with a particular interleaver using a truncated union bound which requires information of the minimum Hamming distance and the number of codewords with the minimum Hamming distance. However, it gives the reliable bound only in the region of the error floor where the minimum Hamming distance is dominant, i.e., in the region of high signal-to-noise ratios. Therefore, currently an upper bound on ML decoding performance for turbo-like code with a particular interleaver and LDPC code with a particular parity check matrix cannot be calculated because of heavy complexity so that only average bounds for ensemble codes can be obtained using a uniform interleaver assumption. In this paper, we propose a new bound technique on ML decoding performance for turbo-like code with a particular interleaver and LDPC code with a particular parity check matrix using ML estimated weight distributions and we also show that the practical iterative decoding performance is approximately suboptimal in ML sense because the simulation performance of iterative decoding is worse than the proposed upper bound and no wonder, even worse than ML decoding performance. In order to show this point, we compare the simulation results with the proposed upper bound and previous bounds. The proposed bound technique is based on the simple bound with an approximate weight distribution including several exact smallest distance terms, not with the ensemble distribution or the uniform interleaver assumption. This technique also shows a tighter upper bound than any other previous bound techniques for turbo-like code with a particular interleaver and LDPC code with a particular parity check matrix.

Analysis of behavior a River Levee based on the Earthquake Scenario (지진 시나리오 기반 하천 제방의 거동 변화 분석)

  • Kim, Jin-Man;Jin, Yoon-Hwa;Han, Heui-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.3
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    • pp.481-487
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    • 2020
  • This study examined the behavior change of river levees during an earthquake by numerical analysis. Unlike conventional research using artificial earthquake waves, earthquake analysis was performed using real earthquake waves. The behavior of a river levee before and after an earthquake was compared and analyzed quantitatively. Studies show that the river levee has a safety factor of approximately 28.5% due to an earthquake. On the other hand, the minimum standard safety factor is satisfied. Vertical effective stress has decreased by 81.8% due to excess pore-water pressure generated by the earthquake. In addition, liquefaction occurs in most of the foundation soil. An examination of the stress-displacement behavior due to the earthquake revealed a large amount of settlement in the backfill layer. Most of the foundation soil yielded. Therefore, the target river levee is quite vulnerable to earthquakes. Through the results of this study, the necessity of refreshing the seismic design standards for river levees is required. This study can be used as basic data for estimating the approximate damage level and vulnerable areas.

Characterization and Purification of Anti-Complement Polysaccharide from Spirodela polyrhiza

  • Min, Jin-Gi;Lee, Doo-Seog;Park, Jeong-Heum;Heo, Moon-Soo;Kim, Tae-Jin;Shim, Kil-Bo;Cho, Young-Je
    • Preventive Nutrition and Food Science
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    • v.9 no.1
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    • pp.21-28
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    • 2004
  • We purified and characterized a crude polysaccharide from Spirodela polyrhiza with anti-complement activities. The crude polysaccharide fraction (SP-0) which had potential anti-complement activity was extracted in hot water for 4 hrs at 10$0^{\circ}C$. The ethanol-precipitate, the crude polysaccharide traction (SP-1), showed a potent anti-complement activity. Further purification of the crude polysaccharide (SP-1) was carried out by cetavlon, ion exchange chromatography and gel column chromatography. Among cetavlon fractions, SP-4 showed the most potent anti-complement activity. When 100 $\mu\textrm{g}$/mL of SP-4 was incubated with an equal volume of normal human serum (NHS), the TCH$_{50}$ was reduced by about 78%. When the SP-4 fraction was further purified by DEAE-Sepharose (Cl$^{[-10]}$ ), the SP-4IIa, SP-4IIb and SP-4IIc, absorbed fractions, were almost the same as the anti-complement activities of SP-4. SP-4IIc, having the greatest potential activation and the highest yield by ion exchange chromatography, was further purified by gel column chromatography on a Sepharose CL-6B column. Four polysaccharide fractions of SP-4IIc-1, SP-4IIc-2, SP-4IIc-3 and SP-4IIc-4 were obtained, consisting mainly of arabinose, rhamnose, galactose and glucose, with approximate molecular weights of about 305,000, 132,000, 64,000 and 12,000, respectively. Among these subfractions, SP-4IIc-1 had the most potent anti-complement activity. When the SP-4IIc-1 aggregate was applied to a gel column chromatography in 10 mM and 50 mM NaCl solution, the position of the peak fractions shifted to a low molecular weight region, and the molecular weight of SP-4IIc-1 decreased with increased NaCl concentration in the gel column chromatography. It was found that the self-aggregation formed spontaneously in void volume by gel column chromatography using Sepharose CL-6B in water and the self-aggregation significantly affected the anti-complement function.

Single Intramuscular-dose Toxicity of Water soluble Carthmi-Flos herbal acupuncture (WCF) in Sprague-Dawley Rats

  • Lee, Hyung-Geol;Kim, Sungchul;Jung, Da-Jung;Choi, Yoo-Min;Sin, Min-Seop;Choi, Seok-Woo;Song, Beom-Yong;Kim, Jong-Uk;Hong, Seung-Won;Yook, Tae-Han
    • Journal of Pharmacopuncture
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    • v.17 no.1
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    • pp.27-34
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    • 2014
  • Objectives: This experiment was conducted to examine the toxicity of Water soluble Carthmi-Flos herbal acupuncture (WCF) by administering a single intramuscular dose of WCF in 6-week-old, male and female Sprague-Dawley rats and to find the lethality dose for WCF. Methods: The experiment was conducted at Biotoxtech according to Good Laboratory Practices under a request by the Korean Pharmacopuncture Institute. This experiment was performed based on the testing standards of "Toxicity Test Standards for Drugs" by the Ministry of Food and Drug Safety. Subjects were divided into 4 groups: 1 control group in which normal saline was administered and 3 test groups in which 0.1, 0.5 or 1.0 mL of WCF was administered; a single intramuscular dose was injected into 5 males and 5 females in each group. General symptoms and body weights were observed/measured for 14 days after injection. At the end of the observation period, hematological and clinical chemistry tests were performed, followed by necropsy and histopathological examinations of the injected sections. Results: No mortalities were observed in any group. Also, symptoms, body weight, hematology, clinical chemistry and necropsy were not affected. However, histopathological examination of the injected part in one female in the 1.0-mL group showed infiltration of mononuclear cells and a multi-nucleated giant cell around eosinophilic material. Conclusion: Administration of single intramuscular doses of WCF in 3 groups of rats showed that the approximate lethal dose of WCF for all rats was in excess of 1.0 mL, as no mortalities were observed for injections up to and including 1.0 mL.

Archaeomagnetic Secular Variation of the Neolithic Age in Korea: Focusing on the Mid-Western Region Sites (한반도 신석기시대의 고고지자기 변동: 중서부지역 유적을 중심으로)

  • Sung, Hyong Mi
    • Journal of Conservation Science
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    • v.29 no.3
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    • pp.223-229
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    • 2013
  • It is not known in details for the A.D. period as the archaeomagnetic dating method to be fully facilitated in Korea but it has prepared for the revised shape of standard curve to trace the geomagnetic field variation, and there were cases to increase the survey on relics on the B.C. period to find out for the detailed archaeomagnetic field variation on the Bronze Age to the Early Iron Age. Furthermore, the survey cases on the relics on the Neolithic Age began to emerge a little by little archaeomagnetic field variation of the Neolithic Age through 34 pieces of the archaeomagnetic measurement data as making active advancement around mid-western region. Data is insufficient yet that it is difficult to find out the detailed trend of modification but it is estimated for approximate appearance. The archaeomagnetic field variation of the Neolithic Age made changes without breaking away from the scope of changes in the A.D. period as in the same way with the Bronze Age, and comparing to the variation of archaeomagnetic field for the Bronze Age, the magnetic inclination shifted within the scope of having almost no difference, but the declination is shown to skewed toward the east in its overall appearance. In addition, the comparison was made with the data of the Jomon Age in Japan and the archaeomagnetic measurement data of Korea has a little bit more depth for while the declination is skewed toward the east for 10 degree or more compared to those of Japan. However, in the part where the data is concentrated most intensely, the data for both countries has significant part to overlap to each other that the archaeomagnetic field variation of the Neolithic Age of Korea showed overall similar variation with certain partial changes when compared to those of Japan.

A Study on the Impact of Oil Price Volatility on Korean Macro Economic Activities : An EGARCH and VECM Approach (국제유가의 변동성이 한국 거시경제에 미치는 영향 분석 : EGARCH 및 VECM 모형의 응용)

  • Kim, Sang-Su
    • Journal of Distribution Science
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    • v.11 no.10
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    • pp.73-79
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    • 2013
  • Purpose - This study examines the impact of oil price volatility on economic activities in Korea. The new millennium has seen a deregulation in the crude oil market, which invited immense capital inflow into Korea. It has also raised oil price levels and volatility. Drawing on the recent theoretical literature that emphasizes the role of volatility, this paper attends to the asymmetric changes in economic growth in response to the oil price movement. This study further examines several key macroeconomic variables, such as interest rate, production, and inflation. We come to the conclusion that oil price volatility can, in some part, explain the structural changes. Research design, data, and methodology - We use two methodological frameworks in this study. First, in regards to the oil price uncertainty, we use an Exponential-GARCH (Exponential Generalized Autoregressive Conditional Heteroskedasticity: EGARCH) model estimate to elucidate the asymmetric effect of oil price shock on the conditional oil price volatility. Second, along with the estimation of the conditional volatility by the EGARCH model, we use the estimates in a VECM (Vector Error Correction Model). The study thus examines the dynamic impacts of oil price volatility on industrial production, price levels, and monetary policy responses. We also approximate the monetary policy function by the yield of monetary stabilization bond. The data collected for the study ranges from 1990: M1 to 2013: M7. In the VECM analysis section, the time span is split into two sub-periods; one from 1990 to 1999, and another from 2000 to 2013, due to the U.S. CFTC (Commodity Futures Trading Commission) deregulation on the crude oil futures that became effective in 2000. This paper intends to probe the relationship between oil price uncertainty and macroeconomic variables since the structural change in the oil market became effective. Results and Conclusions - The dynamic impulse response functions obtained from the VECM show a prolonged dampening effect of oil price volatility shock on the industrial production across all sub-periods. We also find that inflation measured by CPI rises by one standard deviation shock in response to oil price uncertainty, and lasts for the ensuing period. In addition, the impulse response functions allude that South Korea practices an expansionary monetary policy in response to oil price shocks, which stems from oil price uncertainty. Moreover, a comparison of the results of the dynamic impulse response functions from the two sub-periods suggests that the dynamic relationships have strengthened since 2000. Specifically, the results are most drastic in terms of industrial production; the impact of oil price volatility shocks has more than doubled from the year 2000 onwards. These results again indicate that the relationships between crude oil price uncertainty and Korean macroeconomic activities have been strengthened since the year2000, which resulted in a structural change in the crude oil market due to the deregulation of the crude oil futures.

Influence of Discontinuous Layer on Plankton Community Structure and Distribution in Masan Bay, Korea (마산만에서 관찰된 불연속층과 플랑크톤 군집구조와의 관계)

  • HAN Myung-Soo;KIM Se-Wha;KIM Young-Ok
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.24 no.6
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    • pp.459-471
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    • 1991
  • The community structure and micro-scale distribution of plankton in relation to hydrography were investigated in Masan Bay, Korea in October 1989. Warmer and less saline waters with stratification was located in the inner part of the Pudo Strait, and chlorophyll-a and nutrients were higher. Both phytoplankton biomass and nutrients was changed dramatically around the Strait. Offshore/oceanic species in phytoplankton i.e., Chaetoceres decipiens, Rhizosolenia stolterforthii, Rhizosolenia styliformis and Ceratium trichoceros and zooplankton i.e., Sagitta enflata, Oncaea uenusta and Oikopluera longicaudata occurred mainly in well mixed waters of the outer part. This suggests that discontinuous layer seems to play an important role as an approximate border for the plankton population. This layer was located between Station 3 and Station 4 near the Pudo Strait, since the layer consisted of a series of micro-scale discontinuties of salinity and dissolved inorganic nutrients gradient. Phytoplankton patchs of more than 801e1 were found only in the inner part of the bay. Depletion of silicate caused by a rapid assimilation of phytoplankton in the inner part of the bay seemed to be responsible for the decline of blooms.

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