scholarly journals Derivative NMR Spectroscopy for J-Coupled Multiplet Resonances using Short Time Signals (0.5KB) Encoded at Low Magnetic Field Strengths (1.5T). Part II: Water Unsuppressed

Author(s):  
Dževad Belkić ◽  
Karen Belkić

AbstractThe topic of this work is on reliable resolving of J-coupled resonances in spectral envelopes from proton nuclear magnetic resonance (NMR) spectroscopy. These resonances appear as multiplets that none of the conventional nonderivative shape estimators can disentangle. However, the recently formulated nonconventional shape estimator, the derivative fast Padé transform (dFPT), has a chance to meet this challenge. In the preceding article with a polyethylene phantom, using the time signals encoded with water suppressed, the nonparametric dFPT was shown to be able to split apart the compound resonances that contain the known J-coupled multiplets. In the present work, we address the same proton NMR theme, but with sharply different initial conditions from encodings. The goal within the nonparametric dFPT is again to accurately resolve the J-coupled resonances with the same polyethylene phantom, but using raw time signals encoded without water suppression. The parallel work on the same problem employing two startlingly unequal time signals, encoded with and without water suppression in the preceding and the current articles, respectively, can offer an answer to a question of utmost practical significance. How much does water suppression during encoding time signals actually perturb the resonances near and farther away from the dominant water peak? This is why it is important to apply the same dFPT estimator to the time signals encoded without water suppression to complement the findings with water suppression. A notable practical side of this inquiry is in challenging the common wisdom, which invariably takes for granted that it is absolutely necessary to subtract water from the encoded time signals in order to extract meaningful information by way of NMR spectroscopy.

Author(s):  
Dževad Belkić ◽  
Karen Belkić

AbstractThe theme of this study is within the realm of basic nuclear magnetic resonance (NMR) spectroscopy. It relies upon the mathematics of signal processing for NMR in analytical chemistry and medical diagnostics. Our objective is to use the fast Padé transform (both derivative and nonderivative as well as parametric and nonparametric) to address the problem of multiplets from J-coupling appearing in total shape spectra as completely unresolved resonances. The challenge is exacerbated especially for short time signals (0.5 KB, no zero filling), encoded at a standard clinical scanner with the lowest magnetic field strengths (1.5T), as is the case in the present investigation. Water has partially been suppressed in the course of encoding. Nevertheless, the residual water content is still more than four times larger than the largest among the other resonances. This challenge is further sharpened by the following question: Can the J-coupled multiplets be resolved by an exclusive reliance upon shape estimation alone (nonparametric signal processing)? In this work, the mentioned parametric signal processing is employed only as a gold standard aimed at cross-validating the reconstructions from nonparametric estimations. A paradigm shift, the derivative NMR spectroscopy, is at play here through unprecedentedly parametrizing total shape spectra (i.e. solving the quantification problem) by sole shape estimators without fitting any envelope.


2020 ◽  
Vol 23 (10) ◽  
pp. 1182-1194
Author(s):  
A.A. Akhmetzyanov ◽  
A.Yu. Sokolov

Subject. The article focuses on the advanced time-driven tools for allocating overhead expenses, which are based on process-based budgeting. Objectives. We articulate a technique for cost allocation so as to assess the cost of each process with reference to the common time driver. Methods. The study relies upon methods of systematization, classification, analogy and comparison, and summarizes the scientific literature on the subject. Results. The article presents our own suggestions on implementing TD-ABC and TD-ABB into the strategic management accounting process of developer companies. The principles were proved to help more effectively allocate overhead expenses and assess the capacity load of each process performed by functions, departments and employees. Carrying out a comparative analysis, we found certain reserves for utilizing resources more effectively. Conclusions and Relevance. The findings are of scientific and practical significance and can be used by developer and construction businesses. The conclusions can prove helpful for scientific papers, student books, and further research.


2020 ◽  
Vol 86 (8) ◽  
pp. 43-48
Author(s):  
V. V. Semenov

Development of the technologies simulating optical processes in an arbitrary dispersed medium is one of the important directions in the field of optical instrumentation and can provide computer simulation of the processes instead of using expensive equipment in physical experiments. The goal of the study is simulation of scattering of optical radiation by aerosol media using the finite element method to show a practical significance of the results of virtual experiments. We used the following initial conditions of the model: radius of a spherical particle of distilled water is 1 μm, wavelength of the incident optical radiation is 0.6328 μm, air is a medium surrounding the particle. An algorithm for implementation of the model by the finite element method is proposed. A subprogram has been developed which automates a virtual experiment for a group of particles to form their random arrangement in the model and possibility of changing their geometric shape and size within predetermined intervals. Model dependences of the radiation intensity on the scattering angle for single particle and groups of particles are presented. Simulation of the light transmission through a dispersed medium provides development of a given photosensor design and determination of the minimum number of photodetectors when measuring the parameters of the medium under study via analysis of the indicatrix of scattering by a group of particles.


Chaotic systems behavior attracts many researchers in the field of image encryption. The major advantage of using chaos as the basis for developing a crypto-system is due to its sensitivity to initial conditions and parameter tunning as well as the random-like behavior which resembles the main ingredients of a good cipher namely the confusion and diffusion properties. In this article, we present a new scheme based on the synchronization of dual chaotic systems namely Lorenz and Chen chaotic systems and prove that those chaotic maps can be completely synchronized with other under suitable conditions and specific parameters that make a new addition to the chaotic based encryption systems. This addition provides a master-slave configuration that is utilized to construct the proposed dual synchronized chaos-based cipher scheme. The common security analyses are performed to validate the effectiveness of the proposed scheme. Based on all experiments and analyses, we can conclude that this scheme is secure, efficient, robust, reliable, and can be directly applied successfully for many practical security applications in insecure network channels such as the Internet


Eng ◽  
2021 ◽  
Vol 2 (1) ◽  
pp. 99-125
Author(s):  
Edward W. Kamen

A transform approach based on a variable initial time (VIT) formulation is developed for discrete-time signals and linear time-varying discrete-time systems or digital filters. The VIT transform is a formal power series in z−1, which converts functions given by linear time-varying difference equations into left polynomial fractions with variable coefficients, and with initial conditions incorporated into the framework. It is shown that the transform satisfies a number of properties that are analogous to those of the ordinary z-transform, and that it is possible to do scaling of z−i by time functions, which results in left-fraction forms for the transform of a large class of functions including sinusoids with general time-varying amplitudes and frequencies. Using the extended right Euclidean algorithm in a skew polynomial ring with time-varying coefficients, it is shown that a sum of left polynomial fractions can be written as a single fraction, which results in linear time-varying recursions for the inverse transform of the combined fraction. The extraction of a first-order term from a given polynomial fraction is carried out in terms of the evaluation of zi at time functions. In the application to linear time-varying systems, it is proved that the VIT transform of the system output is equal to the product of the VIT transform of the input and the VIT transform of the unit-pulse response function. For systems given by a time-varying moving average or an autoregressive model, the transform framework is used to determine the steady-state output response resulting from various signal inputs such as the step and cosine functions.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Asahi Sato ◽  
Toshihiko Masui ◽  
Akitada Yogo ◽  
Takashi Ito ◽  
Keiko Hirakawa ◽  
...  

AbstractAlthough serum markers such as carcinoembryonic antigen (CEA) and carbohydrate antigen (CA19-9) have been widely used in screening for pancreatic cancer (PC), their sensitivity and specificity are unsatisfactory. Recently, a novel tool of analyzing serum using the short-time Fourier transform (STFT) of free induction decays (FIDs) obtained by 1H-NMR has been introduced. We for the first time evaluated the utility of this technology as a diagnostic tool for PC. Serum was obtained from PC patients before starting any treatments. Samples taken from individuals with benign diseases or donors for liver transplantation were obtained as controls. Serum samples from both groups underwent 1H-NMR and STFT of FIDs. STFT data were analyzed by partial least squares discriminant analysis (PLS-DA) to clarify whether differences were apparent between groups. As a result, PLS-DA score plots indicated that STFT of FIDs enabled effective classification of groups with and without PC. Additionally, in a subgroup of PC, long-term survivors (≥ 2 years) could be discriminated from short-term survivors (< 2 years), regardless of pathologic stage or CEA or CA19-9 levels. In conclusion, STFT of FIDs obtained from 1H-NMR have a potential to be a diagnostic and prognostic tool of PC.


2012 ◽  
Vol 2012 ◽  
pp. 1-14 ◽  
Author(s):  
Yingdong Liu

A one-dimensional cellular automaton traffic flow model, which considers the deceleration in advance, is addressed in this paper. The model reflects the situation in the real traffic that drivers usually adjust the current velocity by forecasting its velocities in a short time of future, in order to avoid the sharp deceleration. The fundamental diagram obtained by simulation shows the ability of this model to capture the essential features of traffic flow, for example, synchronized flow, meta-stable state, and phase separation at the high density. Contrasting with the simulation results of the VE model, this model shows a higher maximum flux closer to the measured data, more stability, more efficient dissolving blockage, lower vehicle deceleration, and more reasonable distribution of vehicles. The results indicate that advanced deceleration has an important impact on traffic flow, and this model has some practical significance as the result matching to the actual situation.


Author(s):  
В. М. Ловинська

Мета статті – розробити нормативи оцінки компонентів стовбура надземної фітомаси соснових деревостанів в умовах Північного Степу України. Методика дослідження. У представленій роботі використана методика збору та обробки дослідного матеріалу проф. П.І. Лакиди. Зроблено статистичну обробку, кореляційний аналіз та пошук регресійних залежностей компонентів фітомаси стовбура сосни звичайної від таксаційних показників деревостану. Результати дослідження. Сформовано робочий масив даних, який характеризує компоненти фітомаси стовбура для оцінювання біотичної продуктивності штучних соснових деревостанів. Розроблено та наведено математичні моделі оцінки фітомаси деревостанів сосни звичайної за компонентами деревини стовбура, деревини стовбура у корі, кори стовбура. Визначено, що збільшення усіх досліджуваних компонентів надземної фітомаси стовбурів відбувається зі зростанням середніх висот та діаметрів деревостанів. Елементи наукової новизни. На основі регресійних моделей побудовано нормативно-інформаційні таблиці для зони Північного Степу України. Практична значущість. Одержані системи нормативів надають можливість оцінювання екологічних та енергетичних ресурсів, а також розрахувати депонування вуглецю у штучних соснових деревостанах досліджуваного регіону. The purpose of the article is to develop the standards for evaluating the trunk components of the aboveground phytomass of pine stands in the Northern Steppe of Ukraine. Methods of research. The method of collecting and processing the research material, developed by Professor P.I. Lakyda, was used in the presented paper. The statistical processing, correlation analysis and the search of regression dependences of phytomass components of the common pine trunk on the taxation indices of the tree stand were made.           The research results. The working data mass has been formed concerning the results of field and laboratory researches, which characterizes the components of the trunk phytomass for assessing biotic productivity of artificial pine stands in the Northern Steppe of Ukraine. Correlation analysis of the relation closeness of the main phytomass components of the tree stands with their basic taxational signs was carried out. A direct close relation of the trunk phytomass components in the bark and wood without bark with the average tree diameter and the height of stands has been established. The value of correlation coefficient of the bark phytomass with all taxational indices, except the density, demonstrates the moderate relation. Mathematical models have been developed and obtained to assess ordinary pine stands’ phytomass by the components of the trunk wood, trunk wood in the bark, and bark of the trunk. It has been determined that the increase of all the studied components of the aboveground trunk phytomass occurred together with increasing the average heights and diameters of tree stands. The elements of scientific novelty. Standard and information tables have constructed on the basis of regression models for the zone of the Northern Steppe of Ukraine. Practical significance. The obtained systems of standards enable to evaluate ecological and power resources and calculate the carbon sequestration in artificial pine tree stands of the studied region.


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