Qualitative Analysis by Derivative Spectrophotometry (II) - Computer-assisted spectral analysis using derivative spectra and Root Mean of Squares of differences -

Park, Man-Ki,Park, Jeong-Hill,Cho, Jung-Hwan The Pharmaceutical Society of Korea 1989 Archives of Pharmacal Research Vol.12 No.4

A computer program which can differentiate compounds whose absorbance spectra are very similar was developed. The program. [SPECMAN PLUS], written in Pascal provides automated spectral comparison techniques, utilizing the values of Root Mean of Squares (RMS) of differences. This comparison routine of the program can deal with spectra of compounds different concentrations and different spectral recording resolutions. In addition, the program was designed applicable to any spectral data of digital form. The program was applied to the UV spectra of 13 pencillins and 5 cephalosporins, whose absorbance spectra are so similar. As a result, all compounds examined could be differentiated from each other.

Performance Evaluation of Cancer Diagnostics Using Autoregressive Features with SVM Classifier : Applications to Brain Cancer Histopathology

D. Vaishali,R. Ramesh,J. Anita Christaline 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.6

Until the recent past, cancer diagnosis was made using histopathology methods, where the pathologists study biopsy samples and make inferences. These inferences are based on cell morphology and tissue distribution which represent randomness in growth and/or in placement. These methods are highly subjective/arbitrary and can sometimes lead to incorrect diagnosis. Nowadays, computer-assisted diagnostic (CAD), based on very large database, can aid in objective judgment. This study emphasizes the contribution of a two-dimensional (2D) autoregressive (AR) model for analysis and classification of histopathological images. In AR model, the parameters consist of a feature set of histopathological images obtained from biopsy samples taken from patients. These features are further used for analysis, synthesis and classification of cancer cells. The Yule-Walker Least Square (LS) method has been used for parameter estimation. The test statistics for the choice of a model order has also been suggested in this paper. It has been inferred that for a given sample image, the neighborhood is unique and solely depends on the properties of samples under consideration. Based on the features of AR parameters, samples are classified into two – healthy tissue and malignant tissue. The feature data sets have been classified using the linear kernel Support Vector Machine (SVM) classifier. In this work, we focus on measuring the performance of cancer diagnostic tests in terms of their recall, specificity, precision and F score. We observe that the fourth-order AR model gives promising results in performance evaluation using SVM classifier.

PCBs 독성 예측을 위한 주요 분자표현자 선택 기법 및 계산독성학 기반 QSAR 모델 개발

김동우 ( Dongwoo Kim ),이승철 ( Seungchel Lee ),김민정 ( Minjeong Kim ),이은지 ( Eunji Lee ),유창규 ( Changkyoo Yoo ) 한국화학공학회 2016 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.54 No.5

EU의 REACH 제도 도입에 따라 각종 화학물질에 대한 독성 및 활성 정보 확보를 위해 화학물질의 분자구조 정보를 기반으로 화학물질의 독성 및 활성을 예측하는 정량적구조활성관계(QSAR)에 대한 연구가 최근 활발히 진행되고 있다. QSAR 모델에 사용되는 분자표현자는 매우 다양하기 때문에 화학물질의 물성 및 활성을 잘 표현할 수 있는 주요한 분자표현자를 선택하는 과정은 QSAR 모델 개발에 있어 중요한 부분이다. 본 연구에서는 화학물질의 분자구조 정보를 나타내는 주요 분자표현자의 통계적 선택 방법과 부분최소자승법(Partial least square: PLS) 기반의 새로운 QSAR 모델을 제안하였다. 제안된 QSAR 모델은 130종의 폴리염화바이페닐(Polychlorinated biphenyl: PCB)에 대한 분배계수(log P)와 14종의 PCBs에 대한 반수 치사 농도(Lethal concentration 50%: LC50) 예측에 사용되고, 제안된 QSAR 모델 예측 정확도는 기존의 OECD QSAR Toolbox에서 제공하는 QSAR 모델과 비교하였다. 관심 화학물질의 분자표현자와 활성정보 간의 높은 상관관계를 갖는 주요 분자표현자를 선별하기 위해서, 상관계수(r)와 variable importance on projections (VIP)기법을 적용하였으며, 화학물질의 독성 및 활성정보를 예측하기 위해 선별된 분자표현자와 활성정보를 이용해 부분최소자승법(PLS)를 사용하였다. 회귀계수(R2)와 prediction residual error sum of square (PRESS)을 이용한 성능평가결과, 제안된 QSAR 모델은 OECD QSAR Toolbox의 QSAR 모델보다 PCBs의 log P와 LC50에 대하여 각각 26%, 91% 향상된 예측력을 나타내었다. 본 연구에서 제안된 계산독성학 기반의 QSAR 모델은 화학물질의 독성 및 활성정보에 대한 예측력을 향상시킬 수 있고 이러한 방법은 유독 화학물질의 인체 및 환경 위해성 평가에 기여할 것으로 판단된다. Recently, the researches on quantitative structure activity relationship (QSAR) for describing toxicities or activities of chemicals based on chemical structural characteristics have been widely carried out in order to estimate the toxicity of chemicals in multiuse facilities. Because the toxicity of chemicals are explained by various kinds of molecular descriptors, an important step for QSAR model development is how to select significant molecular descriptors. This research proposes a statistical selection of significant molecular descriptors and a new QSAR model based on partial least square (PLS). The proposed QSAR model is applied to estimate the logarithm of partition coefficients (log P) of 130 polychlorinated biphenyls (PCBs) and lethal concentration (LC50) of 14 PCBs, where the prediction accuracies of the proposed QSAR model are compared to a conventional QSAR model provided by OECD QSAR toolbox. For the selection of significant molecular descriptors that have high correlation with molecular descriptors and activity information of the chemicals of interest, correlation coefficient (r) and variable importance of projection (VIP) are applied and then PLS model of the selected molecular descriptors and activity information is used to predict toxicities and activity information of chemicals. In the prediction results of coefficient of regression (R2) and prediction residual error sum of square (PRESS), the proposed QSAR model showed improved prediction performances of log P and LC50 by 26% and 91% than the conventional QSAR model, respectively. The proposed QSAR method based on computational toxicology can improve the prediction performance of the toxicities and the activity information of chemicals, which can contribute to the health and environmental risk assessment of toxic chemicals.

정방형 공기덕트 유동의 축방향 속도분포에 관한 전산모사 연구

봉태근,조대환,최지운 한국기계기술학회 2013 한국기계기술학회 학술대회논문집 Vol.2013 No.02

In this paper, numerical investigation of transition characteristics in a square-sectional curved duct flow. Computational fluid dynamic(CFD) simulation was performed using the commercial CFD code FLUENT to investigate the transition characteristics. The flow development is found to depend upon Dean number and curvature ratio. The velocity profiles in center of the duct have lower value than those of the inner and outer walls.

정방형 공기덕트 유동의 축방향 속도분포에 관한 전산모사 연구

봉태근,조대환,최지운 한국기계기술학회 2013 한국기계기술학회 학술대회논문집 Vol.2013 No.08

Partial Least Squares-discriminant Analysis for the Prediction of Hemodynamic Changes Using Near Infrared Spectroscopy

서영욱,이승덕,고달권,김법민 한국광학회 2012 Current Optics and Photonics Vol.16 No.1

Using continuous wave near-infrared spectroscopy, we measured time-resolved concentration changes of oxy-hemoglobin and deoxy-hemoglobin from the primary motor cortex following finger tapping tasks. These data were processed using partial least squares-discriminant analysis (PLS-DA) to develop a prediction model for a brain-computer interface. The tasks were composed of a series of finger tapping for 15 sec and relaxation for 45 sec. The location of the motor cortex was confirmed by the anti-phasic behavior of the oxy- and deoxy-hemoglobin changes. The results were compared with those obtained using the hidden Markov model (HMM) which has been known to produce the best prediction model. Our data imply that PLS-DA makes better judgments in determining the onset of the events than HMM.

Wind loads and wind-resistant behaviour of large cylindrical tanks in square-arrangement group. Part 2: CFD simulation and finite element analysis

Qing Liu,Yang Zhao,Shuqi Cai,Shi-lin Dong 한국풍공학회 2020 Wind and Structures, An International Journal (WAS Vol.31 No.6

To investigate the structural behaviour of grouped tanks under wind loads, 2 problems need to be figured out, wind pressures on tank shells and critical loads of the shell under these pressure distribution patterns. Following the wind tunnel tests described in the companion paper, this paper firstly seeks to obtain wind loads on the external wall in a squarely-arranged cylindrical tank group by numerical simulation, considering various layouts. The outcomes demonstrate that the numerical method can provide similar results on wind pressures and better insights on grouping effects through extracted streamlines. Then, geometrically nonlinear analyses are performed using several selected potentially unfavourable wind pressure distributions. It is found that the critical load is controlled by limit point buckling when the tank is empty while excessive deformations when the tank is full. In particular, significant reductions of wind resistance are found on grouped full tanks compared to the isolated tank, considering both serviceability and ultimate limit state, which should receive special attention if the tank is expected to resist severe wind loads with the increase of liquid level.

Evolutionary Reconstruction

Mohsin Bilal,Muhammad Shams-ur-Rehman,Muhammad Arfan Jaffar 한국산학기술학회 2013 SmartCR Vol.3 No.4

Pseudo-deconvolution is an effective approach to restore space variant degradation (SVD), where each sub-problem is treated as an optimization problem that simultaneously performs image de-blurring and de-noising. De-blurring is an inverse problem primary to visual processing systems. It becomes ill-posed if noise taints the blurry image. Thus the problem is very sensitive to small perturbation in the data. Additive noise has made obsolete classical approaches of inverse filtering and linear algebraic restorations. The restoration formulation for the ill-posed inverse degradations is constrained least square error (CLSE) minimization. Generally, regularization of solutions by “smoothness constraint” is an addition in the classical approaches to cater to the sensitivity of solutions for small perturbations. In this paper, two well-known evolutionary computation (EC) algorithms: 1) the genetic algorithm (GA) with binary and real encoding schemes, and 2) the particle swarm algorithm (PSO), are proposed to evolve the estimated image in order to obtain an optimal solution for restoration with adaptive regularization. Thus the restoration framework presented in this paper is new and novel, such that it reconstructs the image guided by evolutionary computations. Furthermore, modifications in the initial evolutionary framework are proposed to make it a novel hybrid meta-heuristic approach for real-world restoration applications. Quantitative and visual results of the proposed framework are presented in the paper, with comparative analysis within the EC domain and state-of-the-art methods.

Aryabhata의 제곱근 풀이법 -Aryabhatiya를 중심으로-

차유만 ( You Man Cha ),정승석 ( Seung Suk Jung ) 인도철학회 2013 印度哲學 Vol.0 No.39

The paper is to explore the square roots computation in the Aryabhatiya written by Aryabhata(476-550 CE), the first mathematician-astronomers from the classical age of Indian mathematics and Indian astronomy. The difficulty of his explanation on the square roots computation is not from mathematical complications but from implicated descriptions of Sanskrit. In addition, his computations have been in- included cluded numerous exceptional rules. Aryabhata`s regulations implicated in the verse of the Aryabhatiya 2.4 can be basically applied under the square root of five digits. Thorough the application of his calcu-lations, lations, however, it is possible to be calculated the square root of higher oder. For calculating of the square roots Aryabha.a accurately provides the method that the answer can be obtained by repeatedly calculations of its approximations. For example, in order to calculation more than five dig-its of the square the process of root seventeen steps calcu-lations lations is necessary stages. the application of these methods can solved the approximation of irrational number square roots. Thus, it would be understood that the exceptional rules for the necessity of practical application are due to narrow down the approximate estimate for calculating the square roots. This calculated methods do not appeared in any liter-atures atures before the Aryabhatiya of Aryabhataya. Accordingly, it can not be determinated whether the methods is Aryabhata`s thought or is existed previous Aryabhata. Nevertheless, it is noticeably evaluated the worthy of mathematical performance that the calculating of the square roots of single figures can be extended to be solved the higher digits numbers` one. Like identifying in this paper, the rules of calculating appeared in Indian mathematical literatures would be indis-pensably needed for more accurate examinations. Especially it has to be needed that for applied strong implicated de-scriptions scriptions in Sanskrit literatures has to be preceded by careful and diversified methods investigation.

Āryabhaṭa의 제곱근 풀이법_Āryabhaṭīya를 중심으로_

차유만,정승석 인도철학회 2013 印度哲學 Vol.0 No.39

The paper is to explore the square roots computation in the Āryabhaṭīya written by Āryabhaṭa(476–550 CE), the first mathematician-astronomers from the classical age of Indian mathematics and Indian astronomy. The difficulty of his explanation on the square roots computation is not from mathematical complications but from implicated descriptions of Sanskrit. In addition, his computations have been included numerous exceptional rules. Āryabhaṭa’s regulations implicated in the verse of the Āryabhaṭīya 2.4 can be basically applied under the square root of five digits. Thorough the application of his calculations, however, it is possible to be calculated the square root of higher oder. For calculating of the square roots Āryabhaṭa accurately provides the method that the answer can be obtained by repeatedly calculations of its approximations. For example, in order to calculation more than five digits of the square the process of root seventeen steps calculations is necessary stages. the application of these methods can solved the approximation of irrational number square roots. Thus, it would be understood that the exceptional rules for the necessity of practical application are due to narrow down the approximate estimate for calculating the square roots. This calculated methods do not appeared in any literatures before the Āryabhaṭīya of Āryabhaṭa. Accordingly, it can not be determinated whether the methods is Āryabhaṭa’s thought or is existed previous Āryabhaṭa. Nevertheless, it is noticeably evaluated the worthy of mathematical performance that the calculating of the square roots of single figures can be extended to be solved the higher digits numbers’ one. Like identifying in this paper, the rules of calculating appeared in Indian mathematical literatures would be indispensably needed for more accurate examinations. Especially it has to be needed that for applied strong implicated descriptions in Sanskrit literatures has to be preceded by careful and diversified methods investigation. 본론에서는 Āryabhaṭa의 제곱근 풀이법의 다양한 변용을 고찰한다. 이 과정에서 그의 연산법이 의외로 많은 예외 규정을 필요로 한다는 것을 살펴볼 수 있었다. 이와 동시에 일부 연산법의 응용을 통해서 보다 높은 단위의 제곱근을 연산할 수 있다는 것도 확인할 수 있었다. 제곱근을 구하기 위해 Āryabhaṭa가 제시하는 방식은 엄밀히 말해서 근사치를 구하는 것을 반복하여 그 해답을 구하는 방식이다. 이 방식은 무리수의 경우라도 근사치를 구하는 데는 사용될 수 있을 것이다. 그리고 약간의 응용력을 발휘해야 하는 예외 규정을 필요로 하는 것도, 그 발상 자체가 근사치를 좁혀 가는 방식으로 답을 구하고자 하기 때문이라고 이해할 수 있다. Āryabhaṭa가 함축적으로 서술한 연산법은 작은 수의 제곱근을 구하는 것을 확장하여, 보다 큰 수의 제곱근을 구하는 방식으로 응용할 수 있다는 사실은 특기할 만한 수학적 성과라고 평가할 만하다. 다만 인도의 수학적 문헌에 나타난 계산법에 대한 보다 정밀한 검토가 이루어져야 할 것이다. 특히 함축성이 강한 규정적 서술을 공식화하여 적용하는 데에는 신중하고 다각적인 검토가 선행되어야 할 것이다.