• Title/Summary/Keyword: log-polar

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Concentration Level and Grading of Water Quality Components (COD, DIN, DIP, Chlorophyll-a) in Korean Coastal Waters: A Statistical Approach (한국 연안역 수질성분들(COD, DIN, DIP, Chlorophyll-a)의 해역별 농도 특성과 등급화: 통계적 접근)

  • Lim, Dhong-Il;Choi, Hyun-Woo;Kim, Yong-Ok;Jung, Hoi-Soo;Kang, Youg-Shil
    • Ocean and Polar Research
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    • v.33 no.1
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    • pp.13-20
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    • 2011
  • Comprehensive data collection was carried out between 2001-2006 to investigate the concentration levels of chlorophyll-a, nutrients (DIN and DIP), and COD for surface waters of Korean coastal areas. A statistical analysis of these parameters was carried out on the basis of the frequency distribution of their concentration. Furthermore, the numeric grading for chlorophyll-a, DIN, DIP, and COD concentrations were derived statistically from the normalized frequency distribution of log-transformed data. The statistical grading clearly reflects the water quality characteristics of three Korean coastal water bodies (Western, Southern and Eastern coastal zones), which indicate common environmental and ecological characteristics. So, this study could provide useful information to set up the guideline for water quality assessment of Korean coasts.

Visual Object Tracking using Surface Fitting for Scale and Rotation Estimation

  • Wang, Yuhao;Ma, Jun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.5
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    • pp.1744-1760
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    • 2021
  • Since correlation filter appeared in the field of object tracking, it plays an increasingly vital role due to its excellent performance. Although many sophisticated trackers have been successfully applied to track the object accurately, very few of them attaches importance to the scale and rotation estimation. In order to address the above limitation, we propose a novel method combined with Fourier-Mellin transform and confidence evaluation strategy for robust object tracking. In the first place, we construct a correlation filter to locate the target object precisely. Then, a log-polar technique is used in the Fourier-Mellin transform to cope with the rotation and scale changes. In order to achieve subpixel accuracy, we come up with an efficient surface fitting mechanism to obtain the optimal calculation result. In addition, we introduce a confidence evaluation strategy modeled on the output response, which can decrease the impact of image noise and perform as a criterion to evaluate the target model stability. Experimental experiments on OTB100 demonstrate that the proposed algorithm achieves superior capability in success plots and precision plots of OPE, which is 10.8% points and 8.6% points than those of KCF. Besides, our method performs favorably against the others in terms of SRE and TRE validation schemes, which shows the superiority of our proposed algorithm in scale and rotation evaluation.

A Study of the Retention Mechanism of the Monosubstituted Benzenes in Reversed-phase Liquid Chromatography (II) (역상 액체크로마토그래피에서 벤젠 일치환체들의 머무름 메카니즘에 관한 연구 (제 2 보))

  • Lee, Dai-Woon;Choi, Yong-Wook;Lee, Won
    • Journal of the Korean Chemical Society
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    • v.32 no.2
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    • pp.135-143
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    • 1988
  • The correlations between chromatographic parameters of monosubstituted benzenes and several physical parameters in reversed phase liquid chromatography were studied. The relationships between retention data and polarity index were investigated by plotting $log(log k'_S/k'_B)$ vs. $P'_S/P'_B$ which were relative retention and relative polarity index of monosubstituted benzenes with respect to benzene, respectively. The linear relationship between relative retention and polarity index was observed for the monosubstituted benzenes having polar group, while in case of those having nonpolar group, the good linearity was observed by combination with relative molecular weight i.e. $(P'_S/P'_B)/(MW_S/MW_B)$. Multivariant regression analysis, $a(P'_S/P'_B)+b(MW_S/MW_B)$+c did not give significantly better correlations compared to single variant analysis, $a[(P'_S/P'_B)/(MW_S/MW_B)]$+c, but multiple stepwise regression analysis was recommended when several physical parameters simultaneously were chosen. The best correlation between retention data for monosubstituted benzenes taken from the literature and substituent constant(${\pi}$), derived from hydrophobic parameter and the first order molecular connectivity index$(^1{\chi}^{\nu})$, was established for methanol/water mobile phase system. The larger the surface coverage of the stationary phase, the higher was the correlation coefficient between these two parameters and retention data.

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Substituent Effect on the Fungicidal Activity of New N-substituted Benzotriazol-1-yl Derivatives (새로운 N-치환 benzotriazol-1-yl유도체의 항균활성에 미치는 치환기 효과)

  • Yu, Seong-Jae;Sung, Min-Gyu;Kim, Dae-Whang;Sung, Nack-Do
    • Applied Biological Chemistry
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    • v.40 no.1
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    • pp.80-84
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    • 1997
  • Series of new chiral N-substituted benzotriazol-1-yl derivatives were synthesized and their fungicidal activities in vitro against gray mold(Botrytis cinerea), black spot(Alternaria kikuchiana) and phytophthora blight(Phytophthora capsici) were measured by the agar medium dilution method. The substituents effects between the fungicidal activities (obs. $pI_{50}$) and a various physicochemical parameters of phenoxy or thiophenoxy group(X) & alkyl or phenyl group(Y) were analyzed by the multiple regression technique. From the analyzed substituent effects, the structure-activity relationship(SAR) equations shows that the antifungal activities depend on the parameters for the optimal molecular hydrophobicity($({\Sigma}logP)_{opt}$), Van der Waals (${\Sigma}Vw$>0) volume(${\AA}^3$) and inductive constant with electron withdrawing group(${\sigma}_I$,Y>0). The activity in affected by the inductive effect (${\sigma}_I$,Y>${\sigma}_g$X) of Y-group rather than the X-group. The phenoxy substituents, 1, showed higher antifungal activity tn the thiophenoxy substituents, 2. For 1, polar substituent constant(${\sigma}^*$) was an important factor in determining the activity. And the tribromomethyl substituent, 1g showed the highest activity against the tee fungi.

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HVS Model-based Watermarking Robust to Lossy Compression, Cropping, and Scaling (유손실 압축, 잘라내기 및 신축에 대해 견고한 HVS 모델 기반 워터마킹)

  • Hong, Su-Gi;Jo, Sang-Hyeon;Choe, Heung-Mun
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.38 no.5
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    • pp.548-555
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    • 2001
  • In this paper, we proposed a HVS(human visual system) model-based digital image watermarking which is not only invariant to rotation and translation but also more robust to lossy compression, cropping, and scaling as compared to the conventional method. Fourier transform and log-polar mapping is used to make the proposed algorithm invariant to rotation and translation, and in addition, watermark energy is embedded maximally based on spatial frequency sensitivity of HVS without the deterioration of the invisibility. As a result, the robustness of watermarking is improved both in general image processing operations such as cropping, low pass filtering, and lossy compression and in geometrical transforms such as rotation, translation, and scaling. And, by disjoint embedding of the watermark and the template without intersection, the deterioration of invisibility and robustness is prevented. Experimental results show that proposed watermarking is about 30~75 [%] more robust af compared to the conventional methods.

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LPM-Based Digital Watermarking for Forgery Protection in Printed Materials (인쇄물의 위조 방지를 위한 LPM기반의 디지털 워터마킹)

  • Bae Jong-Wook;Lee Sin-Joo;Jung Sung-Hwan
    • Journal of Korea Multimedia Society
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    • v.8 no.11
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    • pp.1510-1519
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    • 2005
  • We proposed a digital watermarking method that it is possible to identify the copyright because the watermark is detected in the first print-scan and to protect a forgery because the watermark is not detected in the second print-scan. The proposed algorithm uses LPM and DFT transform for the robustness to the distortion of pixel value and geometrical distortion. This methods could improve watermark detection performance and image quality by selecting maximum sampling radius in LPM transform. After analyzing the characteristics of print-scan process, we inserted the watermark in the experimentally selected frequency bands that survives robustly to the first print-scan and is not detected in the second print-scan, using the characteristic of relatively large distortion in high frequency bands of DFT As the experimental result, the original proof is possible because average similarity degree 5.13 is more than the critical value 4.0 in the first print-scan. And the detection of forgery image is also possible because average similarity degree 2.76 is less than the critical value 4.0 in the second print-scan.

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Bacteriological Characteristics of Unidentified Vibrio sp., Hemolysin Producer Isolates front Brackish Water -1. Bacteriological Characteristics of Vibrio sp., D9 (V. kumkang) Similar to V. mimicus (기수에서 분리된 용혈독소를 생산하는 미분류 Vibrio sp.의 세균학적 특징 -1. V. mimicus와 유사한 Vibrio sp. D9의 세균학적 특성)

  • KIM Young-Man;OH Hee-Kyung
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.33 no.6
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    • pp.585-590
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    • 2000
  • A hemolysin producing strain was isolated from Kum rivet estuary located in west part of Korea. In the process of identification the isolated strain was similar to V. mimicus but did not show characteristics of known Vibrio species; therefore, the strain was designated as Vibrio sp. D9 ( V. kumkang) tentatively and further identification study was carried out by comparing its bacteriological characteristics, Morphologically Vibrio sp. D9 was a typical straight roe with a polar flagellium. Among known Vibrio species no identical strains were found when using automatic bacteria identification system ($MicioLog^(TM)$system, release 4.0, Biolog Inc., USA) which evaluated the ability of metabolizing 95 kinds of carbon and nitrogen sources. Vibrio sp. D9 showed 18 and 13 different responses as compared to V. mimicus and V. cholerae, respectively. Clear hemolysis zones were observed with the strain against human and sheep blood agar plate, Hemolytic toxicity was confirmed by strong vascular permeability and fatal toxicity against mouse was also observed. Thus the strain was a pathogenic vibrio. Growth conditions for Vibrio sp. D9 were salinity of $0{\~}5.0{\%}$, pH of $6.4{\~}9.8$, temperature of $15{\~}41^{\circ}C$, respectively.

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Establishment of Analytical Method for Pymetrozine Residues in Crops Using Liquid-Liquid Extraction(LLE) (액-액 분배법을 활용한 작물 중 pymetrozine의 잔류분석법 확립)

  • Yoon, Ji-Young;Moon, Hye-Ree;Park, Jae-Hun;Han, Ye-Hoon;Lee, Kyu-Seung
    • The Korean Journal of Pesticide Science
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    • v.17 no.2
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    • pp.107-116
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    • 2013
  • Polar pesticides like pymetrozine (log $P_{ow}$: -0.18) are known to be difficult to analyze. The analytical method of pymetrozine using hydromatrix included in the official method of KFDA was uncommon and provided ambiguous evidence to confirm both the identity and the quantity. Therefore, precise single residue analytical method was developed in representative crops for using liquid-liquid extraction (LLE). The pymetrozine residue was extracted with methanol from 11 representative crops which comprised apple, blueberry, broccoli, cabbage, cherry, crown daisy, hulled rice, Korean cabbage, potato, rice and watermelon. The extract was purified serially by liquid-liquid extraction (LLE) and silica solid phase extraction (SPE). For rice and hulled rice samples, n-hexane partition was additionally adopted to remove nonpolar interferences, mainly lipids. The residue levels were analyzed by HPLC with DAD, using $C_8$ column. LOQ (limit of quantitation) of pymetroizinie was 1 ng (S/N > 10) and MQL (method quantitation limit) was 0.01 mg/kg. Mean recoveries from 11 crop samples fortified at three levels (MQL, 10 ${\times}$ MQL and 50 ${\times}$ MQL) in triplicate were in the range of 83.1~98.5% with coefficients of variation (CV) of less than 10%, regardless of sample type, which satisfies the criteria of KFDA. The method established in this study could be applied to most of crops as an official and general method for analysis of pymetrozine residue.

Distribution of Electrically Conductive Sedimentary Layer in Jeju Island Derived from Magnetotelluric Measurements (MT 탐사자료를 이용한 제주도 지역의 전도성 퇴적층 분포 연구)

  • Lee, Choon-Ki;Lee, Heuisoon;Oh, Seokhoon;Chung, Hojoon;Song, Yoonho;Lee, Tae Jong
    • Geophysics and Geophysical Exploration
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    • v.17 no.1
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    • pp.28-33
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    • 2014
  • We investigate the spatial distribution of highly conductive layer using the one-dimensional inversions of the new magnetotelluric (MT) measurements obtained at the mid-mountain (400 ~ 900 m in elevation) western area of Jeju Island and the previous MT data over Jeju Island, Korea. The conductive layer indicates the sedimentary layer comprised of Seoguipo Fomation and U Formation. There is a definite positive correlation between the top of conductive layer and the earth surface in elevation. On the contrary, the bottom of conductive layer has a negative correlation with the surface elevation. In other words, the conductive layer has a shape of convex lens, which is thickest in the central part. The basement beneath the conductive layer could be concave in the central part of Jeju Island. A kriging considering the correlation between the layer boundary and the surface elevation provides a reliable geoelectric structure model of Jeju Island. However, further studies, i.e. three-dimensional modeling and interpretation integrated with other geophysical or logging data, are required to reveal the possible presence of three-dimensional conductive body near the subsurface vent of Mt. Halla and the causes of the bias in the depths of layer estimated from MT and core log data.

Bacteriological Characteristics of Unidentified Vibrio sp., Hemolysin Producer Isolated from Brackish Water -2. Bacteriological Characteristics of Vibrio sp. E10 Similar to Vibrio mimicus- (기수에서 분리된 용혈독소를 생산하는 미분류 Vibrio sp.의 세균학적 특징 -2. Vibrio mimicus와 유사한 Vibrio sp. E10의 세균학적 특성-)

  • Kim Young Man;Yu Hong Sik;Oh Hee Kyung
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.6
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    • pp.545-550
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    • 2002
  • A hemolysin producing bacterial strain which belong to Vibrio species was isolated from the Kum River estuary. In the process of identification, the strain did not show characteristics of known Vibrio species; thus, the strain was designated as Vibrio sp, E10 (V. kunsan) tentatively and further identification study was carried out by comparing its bacteriological characteristics. Morphologically Vibrio sp, E10 was comma shaped rod with a polar flagellium. Clear hemolysis zones were observed with the strain against human and sheep blood agar. Hemollytic toxicity was confirmed by strong vascular Permeability and fatal toxicity against mouse was also observed. Therefore the strain was a pathogenic vibrio. Growth conditions for Vibrio sp. E10 were ranged salinity of 0$\~$$4.5\%$, pH of 6.2$\~$9.2, temperature of 14$\~$42$^{\circ}C$, respectively, 16S rDNA partial sequence of Vibrio sp, E10 showed $99\%$ homology with dozens of V. cholerae species including V, cholerae El Tor N16961 and V, snmisnfus ATCC 33653T. This strain belonged to Proteobacteria; gamma subdivision; Vibrionacea: Vibrio. But, among knorn Vibrio species no identical styains were found when using automatic bacteria identification system ($MicroLog^{TM}$system, release 4.0, Biolog Inc., USA) which evaluated the ability of metabolizing 95 kinds of carbon and nitrogen sources. Vibrio sp, E10 showed 18 and 11 different responses as compared to V. mimicus and V, cholerae, respectively.