Analysis Of Several Approaches Research Articles

Assistive Systems for Visually Impaired Persons: Challenges and Opportunities for Navigation Assistance.

The inability to see makes moving around very difficult for visually impaired persons. Due to their limited movement, they also struggle to protect themselves against moving and non-moving objects. Given the substantial rise in the population of those with vision impairments in recent years, there has been an increasing amount of research devoted to the development of assistive technologies. This review paper highlights the state-of-the-art assistive technology, tools, and systems for improving the daily lives of visually impaired people. Multi-modal mobility assistance solutions are also evaluated for both indoor and outdoor environments. Lastly, an analysis of several approaches is also provided, along with recommendations for the future.

A bibliometric literature review of stock price forecasting: From statistical model to deep learning approach.

We introduce a comprehensive analysis of several approaches used in stock price forecasting, including statistical, machine learning, and deep learning models. The advantages and limitations of these models are discussed to provide an insight into stock price forecasting. Traditional statistical methods, such as the autoregressive integrated moving average and its variants, are recognized for their efficiency, but they also have some limitations in addressing non-linear problems and providing long-term forecasts. Machine learning approaches, including algorithms such as artificial neural networks and random forests, are praised for their ability to grasp non-linear information without depending on stochastic data or economic theory. Moreover, deep learning approaches, such as convolutional neural networks and recurrent neural networks, can deal with complex patterns in stock prices. Additionally, this study further investigates hybrid models, combining various approaches to explore their strengths and counterbalance individual weaknesses, thereby enhancing predictive accuracy. By presenting a detailed review of various studies and methods, this study illuminates the direction of stock price forecasting and highlights potential approaches for further studies refining the stock price forecasting models.

On the Closure Problem of the Coarse-Grained Hydrodynamics of Turbulent Superfluids

The coarse-grained hydrodynamics of turbulent superfluid fluids describes the fluid flow in terms of two equations for the averaged normal and superfluid velocities. These two equations are coupled via the mutual friction term, which contains the quantity $${\mathcal {L}}(r,t)$$ –the vortex line density (VLD) of the vortex tangle. The question of how to treat the quantity $${\mathcal {L}}(r,t)$$ –the so-called closure procedure is crucial for the correct description of flow of turbulent superfluids. The article provides a critical analysis of several approaches to the closure procedure. The first one, which is usually referred to as HVBK method suggests to express the quantity $${\mathcal {L}}(r,t)$$ via coarse-grained vorticity $$\nabla \times {\mathbf {v}}_{s}$$ using the famous Feynman rule. This method and idea on the vortex bundle structure, which justifies the use of the HVBK approach, are analyzed and discussed in detail. Another approach that has been popular before, but is still used sometimes, is called the Gorter–Mellink relation. This method suggests that the VLD $${\mathcal {L}}(r,t)$$ is proportional to the squared relative velocity between normal and superfluid components $$\propto (v_{n}-v_{s})^{2}$$ . One more variant of the closure procedure, discussed in the paper, is based on the method in which the vortex line density $${\mathcal {L}}(r,t)$$ is not expressed directly via the velocity (and/or vorticity) field, but is an independent equipollent variable, controlled by a separate equation. The latter approach is called as hydrodynamics of superfluid turbulence (HST). The advantages and disadvantages of each method are discussed.

Five Approaches to Deal With Problem of DC Offset in Phase-Locked Loop Algorithms: Design Considerations and Performance Evaluations

The presence of the dc component in the phase-locked loop (PLL) input results in fundamental frequency oscillations in the phase and frequency estimated by the PLL. The removal of these oscillations is a challenging task because of their low frequency. The aim of this paper is to provide a detailed analysis of several approaches that little work has been conducted on their application for addressing the problem of dc offset in the PLL algorithms. These approaches include using the dq -frame delayed signal cancellation (DSC) operator and the notch filter (NF) as the PLL in-loop filtering stages, and using the $\alpha \beta$ -frame DSC operator, the complex coefficient filter, and a cross-feedback network for blocking the dc offset before the PLL input. Design aspects of these methods are presented, some methods to enhance their performances are proposed, and their advantages and disadvantages are evaluated.

Enhancing Public Health Law Communication Linkages

Although interest in the field of public health law has dramatically increased over the past two decades, there remain significant challenges in communicating and sharing public health law-related knowledge. Access to quality information, which may assist in a public health department's efforts to protect the public's health, welfare, and safety, varies widely from jurisdiction to jurisdiction, and interjurisdictional communication remains at best a patchwork quilt with many holes. What follows is an analysis of several approaches the Public Health Law Association or other public health law-related organizations might undertake to serve as a conduit for the identification, gathering, and dissemination of extant public health law information, as well as the development of new public health law-related content, with a particular focus on the use of electronic means for such efforts.

Sampling streaming data with replacement

Simple random sampling is a widely accepted basis for estimation from a population. When data come as a stream, the total population size continuously grows and only one pass through the data is possible. Reservoir sampling is a method of maintaining a fixed size random sample from streaming data. Reservoir sampling without replacement has been extensively studied and several algorithms with sub-linear time complexity exist. Although reservoir sampling with replacement is previously mentioned by some authors, it has been studied very little and only linear algorithms exist. A with-replacement reservoir sampling algorithm of sub-linear time complexity is introduced. A thorough complexity analysis of several approaches to the with-replacement reservoir sampling problem is also provided.

Variability of particulate organic carbon concentration in the north polar Atlantic based on ocean color observations with Sea‐viewing Wide Field‐of‐view Sensor (SeaWiFS)

We use satellite data from Sea‐viewing Wide Field‐of‐view Sensor (SeaWiFS) to investigate distributions of particulate organic carbon (POC) concentration in surface waters of the north polar Atlantic Ocean during the spring–summer season (April through August) over a 6‐year period from 1998 through 2003. By use of field data collected at sea, we developed regional relationships for the purpose of estimating POC from remote‐sensing observations of ocean color. Analysis of several approaches used in the POC algorithm development and match‐up analysis of coincident in situ–derived and satellite‐derived estimates of POC resulted in selection of an algorithm that is based on the blue‐to‐green ratio of remote‐sensing reflectance Rrs (or normalized water‐leaving radiance Lwn). The application of the selected algorithm to a 6‐year record of SeaWiFS monthly composite data of Lwn revealed patterns of seasonal and interannual variability of POC in the study region. For example, the results show a clear increase of POC throughout the season. The lowest values, generally less than 200 mg m−3, and at some locations often less than 50 mg m−3, were observed in April. In May and June, POC can exceed 300 or even 400 mg m−3 in some parts of the study region. Patterns of interannual variability are intricate, as they depend on the geographic location within the study region and particular time of year (month) considered. By comparing the results averaged over the entire study region and the entire season (April through August) for each year separately, we found that the lowest POC occurred in 2001 and the highest POC occurred in 2002 and 1999.

Analysis of Uncertainties in Dynamic Thermophysical Measurements

A technique of analyzing the dependence of the uncertainty of results as applied to a thermophysical experiment is presented. The dependence of the uncertainty of the result of investigation of a sample under a temperature change on the number, uncertainty, and place and moment of experimental sampling is investigated. A comparative analysis of several approaches to solution of this problem is given.

Semiqualitative modelling of bioprocesses

This paper deals with semiqualitative modelling of bioprocesses with a view to their supervision. An analysis of several approaches for modelling shows the difficulties involved in taking into account in a same framework, quantitative and qualitative knowledge, generally available about a process that we want to control. We propose an original approach, placed in the context of semiqualitative modelling, that is supported by a knowledge model the variables and parameters of which are defined by intervals. For these semiqualitative models, we study their properties in simulation and prediction, and more precisely, their fitting based on experimental data. We show that pertinent predictions in a short time can be obtained, making of these semiqualitative models interesting tools for the development of systems for bioprocess supervision

Rural water supply and related services in developing countries — Comparative analysis of several approaches

The proposed paper deals with a comparative analysis of several approaches possible and actually used for a joint action of local institutions and foreign aid in the field of water supply and related services such as sanitation to villages and small rural agglomerations (market towns, etc.) in developing countries. This comparative analysis is based on examples of actual programmes in this field. The authors have participated in most of the programmes selected as examples, at various levels and in various capacities, from conception to design, implementation and/or evaluation (i.e. rural development programmes in Ivory Coast, Ghana (upper region), Benin and Ethiopia. The authors were not involved in other examples such as water supply and/or sanitation to small urban centres in Benin, Ivory Coast, etc. They have, however, witnessed them directly and have obtained, therefore, first-hand information on their organization, execution and results. Several typical examples of actual projects are briefly defined and characterized. The paper undertakes, then, to compare, in a clinical fashion, the advantages and drawbacks of the approaches taken in the various examples presented. The paper finally proposes a recommendation for a realistic approach to joint action between local/domestic and foreign financing/assistance agencies and executing bodies (consultants, contractors) in the field of rural water supply, sanitation, and more generally, health improvement. The definition of this line of approach is made in terms of logical framework, i.e. goals, purposes, outputs and inputs at the various stages of the project, up to actual evaluation of execution and impact if possible; description of practical indicators of the two types of evaluation. A particular attention is given to the problems of technological choices, in view of the constraints imposed by the natural environment, by the human and social patterns; in view also of the institutions and the economy. Another point of importance taken into consideration by the paper is the problem of information, education, and support to users for the introduction, implementation, operation and maintenance of technical developments at village level. Conclusions are drawn as to the relative advantages of this approach over the “classical” approach and its replicability.

Water Plan Ranking and the Public Interest

The public interest, which often serves as the basis for ranking alternative Federal water resources plans, is defined in terms of the following: What factors should be considered, and how should the factors be weighed relative to one another in ranking proposals? Answers to this question provide the framework for an analysis of several approaches that have been used in ranking alternatives, (e.g., economic efficiency, weighted sum of objectives). In the course of examining these approaches, an argument is made in support of trends toward the direct involvement of citizens in the determination of factors and weights. The approaches examined, as they are commonly employed in practice, are shown to be less than satisfactory in terms of involving citizens in determining factors and weights. A process is outlined which integrates public involvement activities into the ranking of alternatives and which has been found useful in the context of Corps of Engineers' water resources studies.