• 한국방송∙미디어공학회:학술대회논문집
• /
• 한국방송공학회 2003년도 정기총회 및 학술대회
• /
• pp.215-218
• /
• 2003

본 논문에서는 MPEG-7에 정의된 오디오 서술자를 이용한 오디오 특징을 기반으로 한 음악 검색 알고리즘을 제안한다. 특히 timbral 특징들은 음색 구분을 용이하게 할 수 있어 음악 검색뿐만 아니라 음악 장르 분류 또는 Query by humming에 이용 될 수 있다. 이러한 연구를 통하여 오디오 신호의 대표적인 특성을 표현 할 수 있는 특징벡터를 구성 할 수 있다면 추후에 멀티모달 시스템을 이용한 검색 알고리즘에도 오디오 특징으로 이용 될 수 있을 것이다 본 논문에서는 방송 시스템에 적용 할 수 있도록 검색 범위를 특정 컨텐츠의 O.S.T 앨범으로 제한하였다. 즉, 사용자가 임의로 선택한 부분적인 오디오 클립만을 이용하여 그 컨텐츠 전체의 O.S.T 앨범 내에서 음악을 검색할 수 있도록 하였다. 오디오 특징벡터를 구성하기 위한 MPEG-7 오디오 서술자의 조합 방법을 제안하고 distance 또는 ratio 계산 방식을 통해 성능 향상을 추구하였다. 또한 reference 음악의 템플릿 구성 방식의 변화를 통해 성능 향상을 추구하였다. Classifier로 k-NN 방식을 사용하여 성능 평가를 수행한 결과 timbral spectral feature들의 비율을 이용한 IFCR(Intra-Feature Component Ratio) 방식이 Euclidean distance 방식보다 우수한 성능을 보였다.

• International Journal of Computer Science & Network Security
• /
• 제23권1호
• /
• pp.1-10
• /
• 2023

Open surface water body extraction is gaining popularity in recent years due to its versatile applications. Multiple techniques are used for water detection based on applications. Different applications of Radar as LADAR, Ground-penetrating, synthetic aperture, and sounding radars are used to detect water. Shortwave infrared, thermal, optical, and multi-spectral sensors are widely used to detect water bodies. A stereo camera is another way to detect water and different methods are applied to the images of stereo cameras such as deep learning, machine learning, polarization, color variations, and descriptors are used to segment water and no water areas. The Satellite is also used at a high level to get water imagery and the captured imagery is processed using various methods such as features extraction, thresholding, entropy-based, and machine learning to find water on the surface. In this paper, we have summarized all the available methods to detect water areas. The main focus of this survey is on water detection especially in small patches or in small areas. The second aim of this survey is to detect water hazards for unmanned vehicles and off-sure navigation.

• 정보과학회 논문지
• /
• 제42권6호
• /
• pp.699-706
• /
• 2015

최근 이미지 컨텐츠에 쉽게 접근할 수 있는 인터넷 환경과 이미지 편집 기술들의 보급으로 근-복사 이미지가 폭발적으로 증가하면서 관련 연구가 활발하게 이루어지고 있다. 그러나 근-복사 이미지 검출 방법으로 주로 쓰이는 BoF(Bag-of-Feature)는 고차원의 지역 특징을 저차원으로 근사화하는 양자화과정에서 서로 다른 특징들을 같다고 하거나 같은 특징을 다르다고 하는 한계가 발생할 수 있으므로 이를 극복하기 위한 후-검증 방법이 필요하다. 본 논문에서는 BoF의 후-검증 방법으로 SIFT(Scale Invariant Feature Transform) 기술자를 128bit의 이진 코드로 변환한 후 BoF 방법에 의하여 추출된 짧은 후보 리스트에 대하여 변환한 코드들간의 거리를 비교하는 방법을 제안하고 성능을 분석하였다. 1500장의 원본이미지들에 대한 실험을 통하여 기존의 BoF 방법과 비교하여 근-복사 이미지 검출 정확도가 4% 향상됨을 보였다.

• 대한화학회지
• /
• 제54권4호
• /
• pp.363-373
• /
• 2010

마약인 모르핀, 헤로인, 코데인, 펜타조신 그리고, 버프레노파인에 대하여 범밀도함수이론에 근거하여 계산 연구를 수행하였다. 약물특이 분자단과 치환기의 기하학적 파라미터는 B3LYP/6-31+G(d) 레벨로 계산하였고, 전자의 구조는B3LYP/6-311++G(d,p) 레벨로 같은 혼성 범함수를 사용하여 계산하였다. 원자의 전하분포는 Mulliken 개체 수 분석에 의하여 구하였다. 보고된 생물학적 활성, 계산된 분배 계수, 전자 및 기하학적 분석을 토대로 펜타조신과 버프레노파인을 새로 제시된 유사화합물에 대한 모델화합물로 선택하였으며, 이들 유사화합물에 대하여 연구한 뒤, 모델화합물과 비교하였다. 본 연구 결과는 약물특이 분자단의 기하학적 구조와 전자 구조가 다른 치환기의 존재 하에서도 변함없이 유지된다는 것을 보여주었다. 제시된 유사화합물들도 모델 분자의 특성을 갖고 있기 때문에, 이들 유사화합물들도 생물학적 활성을 나타낼 것 같다.

• Toxicological Research
• /
• 제35권4호
• /
• pp.295-301
• /
• 2019

In this review, we describe the absorption rates (Caco-2 cell permeability) and hepatic/plasma pharmacokinetics of 53 diverse chemicals estimated by modeling virtual oral administration in rats. To ensure that a broad range of chemical structures is present among the selected substances, the properties described by 196 chemical descriptors in a chemoinformatics tool were calculated for 50,000 randomly selected molecules in the original chemical space. To allow visualization, the resulting chemical space was projected onto a two-dimensional plane using generative topographic mapping. The calculated absorbance rates of the chemicals based on cell permeability studies were found to be inversely correlated to the no-observed-effect levels for hepatoxicity after oral administration, as obtained from the Hazard Evaluation Support System Integrated Platform in Japan (r = -0.88, p < 0.01, n = 27). The maximum plasma concentrations and the areas under the concentration-time curves (AUC) of a varied selection of chemicals were estimated using two different methods: simple one-compartment models (i.e., high-throughput toxicokinetic models) and simplified physiologically based pharmacokinetic (PBPK) modeling consisting of chemical receptor (gut), metabolizing (liver), and central (main) compartments. The results obtained from the two methods were consistent. Although the maximum concentrations and AUC values of the 53 chemicals roughly correlated in the liver and plasma, inconsistencies were apparent between empirically measured concentrations and the PBPK-modeled levels. The lowest-observed-effect levels and the virtual hepatic AUC values obtained using PBPK models were inversely correlated (r = -0.78, p < 0.05, n = 7). The present simplified PBPK models could estimate the relationships between hepatic/plasma concentrations and oral doses of general chemicals using both forward and reverse dosimetry. These methods are therefore valuable for estimating hepatotoxicity.

• Bulletin of the Korean Chemical Society
• /
• 제33권10호
• /
• pp.3285-3292
• /
• 2012

The interaction of thiazole drug with (6,0) zigzag single-walled boron nitride nanotube of finite length in gas and solvent phases was studied by means of density functional theory (DFT) calculations. In both phases, the binding energy is negative and presenting characterizes an exothermic process. Also, the binding energy in solvent phase is more than that the gas phase. Binding energy corresponding to adsorption of thiazole on the BNNT model in the gas and solvent phases was calculated to be -0.34 and -0.56 eV, and about 0.04 and 0.06 electrons is transferred from the thiazole to the nanotube in the phases. The significantly changes in binding energies and energy gap values by the thiazole adsorption, shows the high sensitivity of the electronic properties of BNNT towards the adsorption of the thiazole molecule. Frontier molecular orbital theory (FMO) and structural analyses show that the low energy level of LUMO, electron density, and length of the surrounding bonds of adsorbing atoms help to the thiazole adsorption on the nanotube. Decrease in global hardness, energy gap and ionization potential is due to the adsorption of the thiazole, and consequently, in the both phases, stability of the thiazole-attached (6,0) BNNT model is decreased and its reactivity increased. Presence of polar solvent increases the electron donor of the thiazole and the electrophilicity of the complex. This study may provide new insight to the development of functionalized boron nitride nanotubes as drug delivery systems for virtual applications.

• 지능정보연구
• /
• 제11권1호
• /
• pp.17-33
• /
• 2005

자기공명영상과 계층적 신경망을 이용하여 간경변증을 단계별로 분류하고자 하였다. 내원한 231명의 데이터를 분석하였으며, 각 단계별 분류는 정상,1, 2, 3단계로 분류하였다. TI강조 자기공명 간 영상으로부터 정상 간 실질과 간 경변 결절을 추출하고, 간 경화증의 단계를 객관적으로 해석 분류하였다. 간 경변 분류기 구현은 계층적 신경망을 이용하였고, 명암도 분석과 간 결절 특성을 통하여 정상간과 3단계의 간 경변으로 구분하였다. 제안한 신경망 분류기는 오류 역전파 알고리듬을 이용하였다. 분류결과 인식율이 정상군은 $100\%$, 1 단계는 $82.8\%$, 2 단계는 $87.1\%$, 3 단계는 $84.2\%$의 분류율을 나타내었다. 신경망 분류 결과와 전문의 판독 결과를 서로 비교한 결과 인식률은 매우 높게 나타났다. 만일 더욱더 충분한 데이터나 파라미터를 가지고 지속적으로 수행한다면 간 경변 환자들에게 임상적으로 지원하는 도구뿐만 아니라 의료전문 신경망으로도 기대된다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제14권8호
• /
• pp.3312-3327
• /
• 2020

Plant diseases are a significant yield and quality constraint for farmers around the world due to their severe impact on agricultural productivity. Such losses can have a substantial impact on the economy which causes a reduction in farmer's income and higher prices for consumers. Further, it may also result in a severe shortage of food ensuing violent hunger and starvation, especially, in less-developed countries where access to disease prevention methods is limited. This research presents an investigation of Directional Local Quinary Patterns (DLQP) as a feature descriptor for plants leaf disease detection and Support Vector Machine (SVM) as a classifier. The DLQP as a feature descriptor is specifically the first time being used for disease detection in horticulture. DLQP provides directional edge information attending the reference pixel with its neighboring pixel value by involving computation of their grey-level difference based on quinary value (-2, -1, 0, 1, 2) in 0°, 45°, 90°, and 135° directions of selected window of plant leaf image. To assess the robustness of DLQP as a texture descriptor we used a research-oriented Plant Village dataset of Tomato plant (3,900 leaf images) comprising of 6 diseased classes, Potato plant (1,526 leaf images) and Apple plant (2,600 leaf images) comprising of 3 diseased classes. The accuracies of 95.6%, 96.2% and 97.8% for the above-mentioned crops, respectively, were achieved which are higher in comparison with classification on the same dataset using other standard feature descriptors like Local Binary Pattern (LBP) and Local Ternary Patterns (LTP). Further, the effectiveness of the proposed method is proven by comparing it with existing algorithms for plant disease phenotyping.

• 한국치위생학회지
• /
• 제3권2호
• /
• pp.183-196
• /
• 2003

Purpose: This study sought to identify factors associated with dental hygienists' decisions to leave one dental office and commence practice in another. In addition to, the reasons dental hygienists stay in the profession were investigated. Demographic descriptors, including education level, marital status and age, and employment setting were also examined. Methods: Currently practicing dental hygienists in Korea were surveyed from March to May 2003. Data were collected through a questionnaire. The survey collected information concerning the 461 respondents' personal characteristics and reasons associated with changing positions and staying. Data were analyzed using frequency distributions, independent t-tests and chi-square analyses. All statistical analyses were conducted using the Statistical Package for Social Scientists(SPSS v.10, Chicago, Illinois). Results: The primary reasons for taking up another employment were found to be better offer, inadequate salary and personal conflict with dentist. Secondary reasons stated for changing their job revealed additional factors including inadequate salary, better offer, and lack of benefits. The primary influence in deciding to remaining in the practice of dental hygiene was self-development. Family responsibility, safe environment and professional collaboration were also important factors in deciding to remain in workforce. Conclusion: The position changes of dental hygienists are primarily influenced by better offer. Inadequate salary and conflict with dentist were also important factors in deciding to change employment positions. The findings suggest that dental hygienists who remain in the workforce are positively influenced mainly by self-development. Employers of dental hygienists should be aware of these factors in employing process. If more hygienists could remain longer in their positions, the manpower situation would be affected positively.

• 한국조경학회지
• /
• 제13권1호
• /
• pp.43-66
• /
• 1985

Korea needs proper and rational public policies on conservation and use of forest land and other natural resources because of the accelerating expansion of national land developments in recent years. Unfortunately, there is no systematic planning system to support the needs. Generally, forest land use planning needs suitability analysis based on efficient land classification system. The goal of this study was to classify a forest land using multivariate satistical methods. A case study was carried out in winter of 1983 on a mountainous area higher than 100m above sea level located at Mt. Kwanak in Anyang -city, Kyung-gi-do (province). The study area was 19.80 km$^2$wide and was divided into 1, 383 Operational Taxonomic Units (OTU's) by a 120m$\times$120m grid. Fourteen descriptors were identified and quantified for each OTU from existing national land data : elevation, slope, aspect, terrain form, geologic material, surface soil permeability, topsoil type, depth of the solum, soil acidity, forest cover type, stand size class, stand age class, stand density class, and simple forest soil capability class. For this study, a FORTRAN IV program was written for input and output map data, and the computer statistics packages, SPSS and BMD, were used to perform the multivariate statistical analysis. Fourteen variables were analyzed to investigate the characteristics of their fire quench distribution and to estimate the correlation coefficients among them. Principal component analysis was executed to find the dimensions of forest land characteristics, and factor scores were used for proper samples of OTU throughout the study area. In order to develop the classes of forest land classification based on 102 surrogates, cluster and discriminant analyses of principal descriptor variable matrix were undertaken. Results obtained through a series of multivariate statistical analyses were as follows ; 1) Principal component analysis was proved to be a useful tool for data selection and identification of principal descriptor variables which represented the characteristics of forest land and facilitated the selection of samples.