• ALGAE
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• v.18 no.3
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• pp.225-232
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• 2003

Species composition, community structure and biodiversity of marine benthic community were studied in the rocky shore of Dongbaekseom, Busan. A total of 82 species of marine algae including 4 Cyanophyta, 11 Chlorophyta, 20 Phaeophyta and 47 Rhodophyta are listed. The dominant algal species were Ulva pertusa, Chondria crassicaulis, Corallina spp. and Melobesioidean algae. Sargassum thunbergii, Chondracanthus intermedia, Gelidium divaricatum and Ralfsia verrucosa were subdominant in cases of different seasons and vertical layers. Chthamalus challengeri, Littorina brevicula and Mytilus edulis were dominant zoobenthic species upper-middle layer of the intertidal zone. The community structure of this area seemed to be controlled by spatial competition with benthic marine algae. The species diversity indices estimated from different sources were quite different. Indices from coverage were 1.87, 3.98 from frequency, 2.26 from the average of total frequency and coverage and 2.15 from importance value. The similarity indices on the present study showed decreasing trends comparing to the previous benthic algal composition researches.

• Journal of the Korea Society of Computer and Information
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• v.26 no.11
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• pp.149-156
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• 2021

Among various implementation techniques of recommender systems, collaborative filtering selects nearest neighbors with high similarity based on past rating history, recommends products preferred by them, and has been successfully utilized by many commercial sites. Accurate estimation of similarity is an important factor that determines performance of the system. Various similarity measures have been developed, which are mostly based on integrating traditional similarity measures and several indices already developed. This study suggests a similarity measure of a novel approach. It separates the common rating area between two users by the magnitude of ratings, estimates similarity for each subarea, and integrates them with weights. This enables identifying similar subareas and reflecting it onto a final similarity value. Performance evaluation using two open datasets is conducted, resulting in that the proposed outperforms the previous one in terms of prediction accuracy, rank accuracy, and mean average precision especially with the dense dataset. The proposed similarity measure is expected to be utilized in various commercial systems for recommending products more suited to user preference.

• Korean Journal of Remote Sensing
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• v.36 no.1
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• pp.55-65
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• 2020

Image classification needs the spectral similarity comparison between spectral features of each pixel and the representative spectral features of each class. The spectral similarity is obtained by computing the spectral feature vector distance between the pixel and the class. Each spectral feature contributes differently in the image classification depending on the class separability of the spectral feature, which is computed using a suitable vector distance measure such as the Bhattacharyya distance. We propose a method to determine the weight value of each spectral feature in the computation of feature vector distance for the similarity measurement. The weight value is determined by the ratio between each feature separability value to the total separability values of all the spectral features. We created ten spectral features consisting of seven bands of Landsat-8 OLI image and three indices, NDVI, NDWI and NDBI. For three experimental test sites, we obtained the overall accuracies between 95.0% and 97.5% and the kappa coefficients between 90.43% and 94.47%.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.153-154
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• 2008

This paper presents a window-based software package for the education and training for the reduction of power system by using locational marginal price (LMP), clustering, and similarity indices of each bus. The developed package consists of three modules: 1) the LMP module, 2) the Clustering module and 3) the Reduction module. Each module has a separated and interactive interface window. First of all, LMPs are created in the LMP module, and then the Clustering module carries out clustering based on the results of the LMP module. Finally, groups created in this Clustering module are reduced by using the similarity indices of each bus. The developed package displays a variety of tables for results of the LMPs of base network, voltages, phases and power flow of reduced network so that the user can easily understand the reduction of network. To demonstrate the performance of the developed package, it is tested for the IEEE 39-bus power system.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.733-740
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• 2003

To find a new substance with superior melanogenesis inhibitory activity, the bioactivities of alkyl-3,4-dihydroxy-5-substituted benzoate (A) and N-alkyl-3,4-dihydroxy-5-substituted benzamide (B) derivatives as substrate of tyrosinase were measured in mouse melanoma cells. And the bioactivities analyzed using comparative molecular similarity indices analysis (CoMSIA). From the CoMSIA model, when cross-validation value (q$^2$) is 0.713 at four components, the pearson correlation coefficient ($r^2$) is 0.900. Unknown compounds were predicted, using QSAR analyzed results from the CoMSIA methods. Excellent agreement was obtained between the measured and the predicted bioactivities of unknown compounds. As the results of prediction from CoMSIA, we could conclude that the bioactivities were increased from pl$_{50}$=3.18-4.80 to above 5.17 by creation of 6-methylheptyl, n-pentylphenyl and 2-hydroxypentylphenyl group etc,.,.

• Journal of Integrative Natural Science
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• v.8 no.4
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• pp.273-284
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• 2015

Chemoattractant Receptor Homologous molecule expressed on Th2 cells (CRTh2) is a chemoattractant receptor with seven transmembrane helices targeted for inflammatory diseases such as asthma and allergic rhinitis. In this study, pharmacophore based Comparative Molecular Similarity Indices Analysis (CoMSIA) were performed on the series of 2-(2-(benzylthio)-1H-benzo[d]imidazol-1-yl) acetic acids derivatives. Initially, GASP module was used for generation of pharmacophore models using five highly active compounds from the dataset. Among the generated pharmacophores, the best pharmacophore model was selected based on fitness score and was used as template for the alignment of compounds which was used for CoMSIA analysis. The best predictions were obtained utilizing steric, hydrophobic and H-bond acceptor parameters showing a $q^2$=0.559 and $r^2$=0.730. 15 test set compounds was used to investigate the predictive ability of the CoMSIA model. Contour maps suggested that presence of bulky substituents and H-bond acceptor atoms at $5^{th}$ position of benzene ring will increase the activity of the compounds. The results obtained from this study will be useful to design more potent CRTh2 antagonists.

• Journal of Korean Society for Quality Management
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• v.49 no.2
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• pp.145-159
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• 2021

Purpose: A statistical similarity evaluation to compare pharmacokinetics(PK) profile data between nonclinical and clinical experiments has become a significant issue on many drug development processes. This study proposes a new similarity index by considering important parameters, such as the area under the curve(AUC) and the time-series profile of various PK data. Methods: In this study, a new profile similarity index(PSI) by using the concept of a process capability index(Cp) is proposed in order to investigate the most similar animal PK profile compared to the target(i.e., Human PK profile). The proposed PSI can be calculated geometric and arithmetic means of all short term similarity indices at all time points on time-series both animal and human PK data. Designed simulation approaches are demonstrated for a verification purpose. Results: Two different simulation studies are conducted by considering three variances(i.e., small, medium, and large variances) as well as three different characteristic types(smaller the better, larger the better, nominal the best). By using the proposed PSI, the most similar animal PK profile compare to the target human PK profile can be obtained in the simulation studies. In addition, a case study represents differentiated results compare to existing simple statistical analysis methods(i.e., root mean squared error and quality loss). Conclusion: The proposed PSI can effectively estimate the level of similarity between animal, human PK profiles. By using these PSI results, we can reduce the number of animal experiments because we only focus on the significant animal representing a high PSI value.

• The Korean Journal of Pesticide Science
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• v.7 no.2
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• pp.100-107
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• 2003

To improve the growth inhibitory activity against the shoot and root of rice plant (Oryza sativa L) and barnyard grass (Echinochloa crus-galli), a series of N-substituted phenyl-3,4-dimethylmaleimdes derivatives as substrates were synthesized and then their the inhibitory activities of protoporphyrinogen oxidase (1.3.3.4), protox were measured. The quantitative structure-activity relationships (QSAR) between structures and the inhibitory activities were studied quantitatively using the 2D-QSAR method. And also, molecular sharp similarity between the substrate derivatives and protogen, substrare of protox enzyme were studied. The activities of the two plants indicated that barnyard grass had a higher activity than the rice plant and their correlation relationships have shown in proportion for each. Accordingly, the results of SARs suggest that the electron donating groups as $R_2=Sub.X$ group will bind to phenyl ring because the bigger surface area of negative charged atoms in the substrate molecule derivatives may increase to the higher the activity against barnyard grass. Based on the molecular shape similarity, when the derivatives and protogen, subsbrate of protox enzyme were superimposed by atom fitting, the similarity indices (S) were above 0.8 level but the correlation coefficients (r) between S values and the activities showed not good.

• Journal of Integrative Natural Science
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• v.9 no.3
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• pp.177-184
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• 2016

CXC chemokine receptor 2 (CXCR2) is a prominent chemokine receptor on neutrophils and it regulates the neutrophilic inflammation in the lung diseases. CXCR2 antagonist may reduce the neutrophil chemotaxis and alter the inflammatory response. Hence, in the present study, ligand based Comparative Molecular Similar Indices Analysis (CoMSIA) was performed on a series of CXCR2 antagonist named pyrimidine-5-carbonitrile-6-alkyl derivatives. The optimum CoMSIA model was obtained with statistically significant cross-validated coefficients ($q^2$) of 0.582 and conventional coefficients ($r^2$) of 0.987 with steric, electrostatic, hydrophobic, donor and acceptor fields. The contour maps suggest the important structural modifications and this study can be used to guide the development of potent CXCR2 antagonist.

• Korean Journal of Microbiology
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• v.25 no.3
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• pp.229-237
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• 1987

To determine the characteristics of heterotrophic bacterial community in estuarine ecosystem, water and sediment samples were taden from Naktong estuary. All isolates were compared with 73 characters and described by cluster analysis. With same characters, 30 reference strains were able to divide into approximate species level at 80% similarity (S value). Diversity indices ($H^{1}$) of sediment column isolates were higher than water column isolates. The bacterial community commonly appeared in water and sediment column was reduced with going to downstream. Tolerance indices for temperature (Pt) and salinity (Ps) were also higher in sediment isolates than in water isolates. The bacterial community in sediment column is believed to be composed with diverse populations compared to water column and maintains its stability against various environmental changes with high physiological tolerances.