Analytic Reference Research Articles

Adaptive Security Activities Selection Model Using Multi-Criteria Decision-Making Methods

Adaptive security activities are a list of recommended security activities to be integrated smoothly with the software development life cycle (SDLC) to produce a secure application software. Adaptive security activities are needed due to the emergence of factors and constraints which have been determined as one of the reasons for the underutilisation of security activities implementation, especially in the earlier phase of software development process. Security activities selection models were proposed to select and recommend security activities but the models were focused on certain factors or as a solution for specific constraints, and thus the recommended security activities were not adaptive. Consequently, an adaptive security activities selection (ASAS) model was proposed by combining the factors and constraints faced by the development team in selecting security activities. The model consisted of two integrated multi-criteria decisionmaking (MCDM) methods, namely Analytic Network Process (ANP) and Reference Ideal Method (RIM). ANP was used to prioritise and weight the criteria while RIM was used to measure and evaluate the security activities with the value of constraints in regard to each criterion. To validate the model a case study was performed on four inhouse web application development teams in the Malaysian public sector. The proposed model was able to recommend security activities in the requirement and design phase based on different constraints faced by each of the development teams. The model was adaptive due to its flexibility and ability to change and suit different evolved conditions when recommending the security activities.

Computer-Assisted Corpus Analysis: An Introduction to Concepts, Processes, and Decisions

<bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Problem:</b> This tutorial aims to guide readers through key concepts, basic processes, and common decision points that inform computer-assisted corpus-based research in technical, professional, and scientific communication (TPSC). <bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Key concepts:</b> Based on our collaborative experiences and an example developed for this tutorial, key concepts of corpus analysis useful to TPSC researchers and practitioners include the following: corpus location, text preparation, and programming language and software selection. <bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Key lessons:</b> These key concepts can be used to establish basic processes and decision points that, in turn, yield lessons related to the usefulness of lexicogrammatical language models and the significance of multidisciplinarity. <bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Implications:</b> Although corpus research is a growing and important part of the field of TPSC, challenges remain in terms of language model variety and ethical considerations. At least in part, these challenges can be met, respectively, by alignment between corpus and analytic tools and reference to the Common Rule and related international standards.

Utilization of Palliative Care in Veterans Admitted With Heart Failure Experiencing Homelessness.

Patients experiencing housing insecurity have numerous barriers affecting their utilization of medical care. Determine if housing insecurity is associated with palliative care (PC) encounters and hospice services in patients with heart failure who receive care in United States Veterans Affairs (VA) medical centers. This retrospective study included inpatients in VA hospitals with a primary diagnosis of congestive heart failure from 2010 to 2020. Housing stability was collected from coding and separated into three cohorts: at risk for homelessness, experiencing homelessness, and stably housed. The primary outcome was a PC encounter during admission and the stably housed cohort was used as the analytic reference. Inverse-probability-weighting (IPTW) was calculated to adjust the likelihood of receiving PC during the index admission. Seventy thousand eight hundred fourty nine veterans were identified. Veterans were identified as at risk for homelessness (n=4039, 5.7%), experiencing homelessness (n=1967, 2.8%) and stably housed (n=64,843, 91.5%). PC was delivered to veterans at risk for homelessness (n=484, 12.0%), veterans experiencing homelessness, (n=161, 8.2%) and patients with stable housing (n=6249, 9.6%). Relative to the stably housed and adjusted for IPTW, those at risk for homelessness received PC services similarly (adjusted OR=1.06, 95% CI 0.94,1.19) and those experiencing homelessness were at lower odds of receiving PC services (adjusted OR=0.62, 95% CI 0.52,0.75). Housing stability may be a factor in Veterans receiving PC during hospitalization for heart failure. While the logistical challenges of delivering PC and hospice to people experiencing homelessness are daunting, advocating for these services shows commitment to reducing suffering in life-limiting Illness.

State of knowledge and future research needs on microplastics in groundwater.

Microplastics (MPs) are widespread in aquatic and soil environments. This study targets the issue of MPs' transfer from soil to groundwater. Scientific papers were collected and analyzed using a text-mining approach that classifies text segments. This allowed the identification of four research topics and the organization of the results into a summarizing table. Those four topics are sources of groundwater MPs, main types of MPs (physico-chemical properties, polymer units, shapes, and size), human exposure (mainly drinking water), and potential environmental and human effects. Compared to the research of MP on aquatic or soil compartments, scientific data on MP in groundwater are less substantial. Current results show a divergence due to differences in context (alluvial aquifer, fractured rock aquifer, karst aquifer, etc), collecting, sampling, and analytical methods. This divergence requires further research with standardized analytic protocols and reference materials. The associated research gaps were identified by using the same approach. The following five topics emerged: (1) the transfer of MPs from soil to underground, (2) the contribution of groundwater to drinking water microplastic pollution, (3) the interaction with other contaminants, (4) the human and environmental effects, and (5) the protective and remediation solutions.

COVID-19 and the state in Africa: The state is dead, long live the state

In this article, I am concerned about how countries around the world have coped and are coping with the unprecedented COVID-19 turn of events, which has brought all life to a screeching halt. The state everywhere has been called upon to respond effectively to the associated morbidities and mortalities and plot for a post-COVID-19 era. My interest lies in how the weakening of the state in Africa in the last 30 years complicates the continent’s capacity to confront the pandemic adequately. I focus primarily on the Ghanaian case as my analytic reference. I argue that in spite of the attempts in the public administration literature and neoliberalization policy formation to undermine the African state as a key vehicle for development, this pandemic brings it right back to the center of things.

Establishing guidelines to harmonize tumor mutational burden (TMB): in silico assessment of variation in TMB quantification across diagnostic platforms: phase I of the Friends of Cancer Research TMB Harmonization Project

BackgroundTumor mutational burden (TMB), defined as the number of somatic mutations per megabase of interrogated genomic sequence, demonstrates predictive biomarker potential for the identification of patients with cancer most likely...

Challenges in Developing Analytically Validated Laboratory-Derived Dietary Supplement Databases

The Dietary Supplement Label Database (DSLD) is sponsored by the Office of Dietary Supplements (ODS) and the National Library of Medicine (NLM). It provides a searchable, free database of the contents of ∼65,000 supplement labels. A companion database of analytically verified product labels [the Dietary Supplement Ingredient Database (DSID)] was created by ODS, NLM, and the USDA. There are considerable challenges to populating both databases, but the DSID faces unique analytic chemistry challenges. This article describes the challenges to creating analytically verified marketplace surveys of dietary supplement (DS) product content claims for inclusion in public databases. Nutritionists and public health scientists require information on actual exposures to DS constituents because labeled content may not match labeled product content. Analytic verification of composition of DSs provides a link to actual exposure. A public database of analytically derived DS content was developed to provide more accurate estimates of dietary intake in population-based epidemiologic studies. The DSID has conducted surveys of several types of vitamin- and mineral-containing DSs. Results showing label content claims as analytically derived values are available in the current DSID. A recent pilot project explored the feasibility of adding botanical DS products to the DSID. Candidates for future botanical DSID studies will be based on sales volume, potential public health impacts, and the availability of validated analytic methods and reference materials. Databases like DSID and the DSLD are essential for researchers and clinicians to evaluate dietary ingredient intakes in population-based epidemiologic studies. Together, these databases provide a picture of the DS marketplace. The DSID provides an analytic survey of marketed DSs. However, selection of future botanical supplements for DSID evaluation involves analytic challenges. Even when appropriate resources are available, method selection and data evaluation are resource- and time-consuming.

Reference Data for Polysomnography-Measured and Subjective Sleep in Healthy Adults.

Reference data for sleep are needed for the interpretation of clinical sleep parameters. This analysis aimed to provide polysomnography-measured, spectral analytic and subjective reference data based on a sample of healthy adults. In addition, effects of age and sex were investigated. The sample was selected from the archival database of the Sleep Center at the University Medical Center Freiburg and consisted of 206 healthy adults aged 19 to 73 years. For an adaptation and a second examination night, polysomnography parameters, spectral analytic data, and subjective sleep estimations are presented. With increasing age, sleep became shorter (less total sleep time, more wake time after sleep onset) and lighter (eg, more percentage of stage N1 sleep, increase in fast activity in the beta range). Sleep in females was deeper than sleep in males (eg, higher percentage of stage N3 sleep). Females had higher overall power density than males. Altogether, it is apparent that sleep parameters exhibit high standard deviations, suggesting a high variability within healthy adults and complicating the specification of reference values. Our data suggest that the informative value of sleep reference data in healthy individuals is limited because of high interindividual and intraindividual variation within sleep variables. More research, preferably in the form of meta-analyses and/or large international databases, is needed to further investigate the relevance of such reference data for mental and physical health. In the absence of such knowledge, giving patients feedback about deviations from the norm in their sleep profile may give rise to ill-founded concerns and worry.

A Review of Methodology for Evaluating the Performance of Atmospheric Transport and Dispersion Models and Suggested Protocol for Providing More Informative Results

Many models exist for predicting the atmospheric transport and dispersion of material following its release into the atmosphere. The purpose of these models may be to support air quality assessments and/or to predict the hazard resulting from releases of harmful materials to inform emergency response actions. In either case it is essential that the user understands the level of predictive accuracy that might be expected. However, contrary to expectation, this is not easily determined from published comparisons of model predictions against data from dispersion experiments. The paper presents and reviews the methods adopted and issues involved in comparing the predictive performance of atmospheric transport and dispersion models to experimental data, by reference to a number of experimental data sets and comparison results. It then presents an approach which is designed to make the performance of atmospheric dispersion models more transparent, through clearly defining the basis on which the comparison is made, and comparing the performance of the chosen model to that of a reference model. Such an approach establishes a clear baseline against which the accuracy of models can be evaluated and the performance benefits of more sophisticated approaches quantified. The use of a simple analytic reference model applicable to continuous ground level releases in open terrain and urban areas is shown as a proof-of-principle.

Conditional Lyapunov exponents and transfer entropy in coupled bursting neurons under excitation and coupling mismatch

This work has a twofold aim: (a) to analyze an alternative approach for computing the conditional Lyapunov exponent (λcmax) aiming to evaluate the synchronization stability between nonlinear oscillators without solving the classical variational equations for the synchronization error dynamical system. In this first framework, an analytic reference value for λcmax is also provided in the context of Duffing master-slave scenario and precisely evaluated by the proposed numerical approach; (b) to apply this technique to the study of synchronization stability in chaotic Hindmarsh-Rose (HR) neuronal models under uni- and bi-directional resistive coupling and different excitation bias, which also considered the root mean square synchronization error, information theoretic measures and asymmetric transfer entropy in order to offer a better insight of the synchronization phenomenon. In particular, statistical and information theoretical measures were able to capture similarity increase between the neuronal oscillators just after a critical coupling value in accordance to the largest conditional Lyapunov exponent behavior. On the other hand, transfer entropy was able to detect neuronal emitter influence even in a weak coupling condition, i.e. under the increase of conditional Lyapunov exponent and apparently desynchronization tendency. In the performed set of numerical simulations, the synchronization measures were also evaluated for a two-dimensional parameter space defined by the neuronal coupling (emitter to a receiver neuron) and the (receiver) excitation current. Such analysis is repeated for different feedback couplings as well for different (emitter) excitation currents, revealing interesting characteristics of the attained synchronization region and conditions that facilitate the emergence of the synchronous behavior. These results provide a more detailed numerical insight of the underlying behavior of a HR in the excitation and coupling space, being in accordance with some general findings concerning HR coupling topologies. As a perspective, besides the synchronization overview from different standpoints, we hope that the proposed numerical approach for conditional Lyapunov exponent evaluation could outline a valuable strategy for studying neuronal stability, especially when realistic models are considered, in which analytical or even Jacobian evaluation could define a laborious or impracticable task.

Comparative study on mesh-based and mesh-less coupled CFD-DEM methods to model particle-laden flow

A comparative study on mesh-based and mesh-less Computational Fluid Dynamics (CFD) approaches coupled with the Discrete Element Method (DEM) is presented. As the mesh-based CFD approach a Finite Volume Method (FVM) is used. A Smoothed Particle Hydrodynamics (SPH) method represents mesh-less CFD. The unresolved fluid model is governed by the locally averaged Navier-Stokes equations. A newly developed model for applying boundary conditions in the SPH is described and validation tests are performed. With the help of the presented comparative tests, the similarities and differences of DEM-FVM and DEM-SPH methods are discussed. Three test cases, comprised of a single solid particle sedimentation test, flow through a porous block and sedimentation of a porous block, are performed using both methods. Drag forces acting on solid particles highly depend on local fluid fractions. For comparative reasons, the size of a cell in FVM is chosen such that fluid fractions match those computed in SPH. In general, DEM-FVM and DEM-SPH methods exhibit good agreement with analytic reference results. Differences between DEM-SPH and DEM-FVM approaches were found mostly due to differences in computed local fluid fractions.

MO-FG-CAMPUS-JeP1-02: Proton Range Verification of Scanned Pencil Beams Using Prompt Gamma Imaging

Purpose: Prompt gammas are emitted along the proton beam path and have an emission profile correlated with the depth dose profile. In this study, the accuracy of in-vivo proton range verification using a 1-D prompt gamma camera is assessed. Methods: The 1-D camera is comprised of a tungsten slit collimator positioned in front of a linear array of LYSO scintillating crystals coupled to silicon photomultipliers. The imaged gamma profiles of individual pencil beam spots and energy layers were analyzed by determining the relative shifts from the expected gamma profiles based on analytic prediction or reference measurements. The range retrieval precision was evaluated by reproducibility measurements and by irradiation through a heterogeneous phantom composed of materials with known stopping power ratios. The camera was evaluated at clinical doses in pencil beam scanning mode on a head-and-neck phantom (HN). Two scenarios were studied: 5 mm systematic range error; and setup error of 10 mm transverse to the proton beam. Results: The camera range retrieval precision was 2 mm at clinical doses. For the heterogeneous phantom and HN phantom studies, the discrepancies between the analytic model and measurements were less than 2 mm for both spot and iso-energy layer analysis. For the simulated 5 mm range error, the retrieved shifts were 4.3±2.0 mm. For the 10 mm setup error, large shifts (> 4 mm) were observed for some spots due to differences in the irradiated and expected beam path from the measurements without setup error. Conclusion: Our studies demonstrated that in-vivo proton range verification is feasible using a 1D prompt gamma camera with a 2 mm range retrieval precision. Pencil beam spot under or over ranging can be detected via comparison between measured and expected profiles.

Improving the Calibration Efficiency of an Array Fed Reflector Antenna Through Constrained Beamforming

Calibrating for the radiation pattern of a multi-beam Phased array feed (PAF) based radio telescope largely depends on the accuracy of the pattern model, and the availability of suitable reference sources to solve for the unknown parameters in the pattern model. It is shown how the efficiency of this pattern calibration for PAF antennas can be improved by conforming the beamformed far field patterns to a two-parameter physics-based analytic reference model through the use of a linearly constrained minimum variance (LCMV) beamformer. Through this approach, which requires only a few calibration measurements, an accurate and simple pattern model is obtained. The effects of the model parameters on the directivity and sidelobe levels of multiple scanned beams are investigated, and these results are used in an example PAF beamformer design for the proposed MeerKAT antenna. Compared to a typically used maximum directivity (MaxDir) beamformer, the proposed constrained beamforming method is able to produce beam patterns over a wide Field-of-View (FoV) that are modeled with a higher degree of accuracy and result in a significant reduction in pattern calibration complexity.

Bio-inspired adaptive feedback error learning architecture for motor control

This study proposes an adaptive control architecture based on an accurate regression method called Locally Weighted Projection Regression (LWPR) and on a bio-inspired module, such as a cerebellar-like engine. This hybrid architecture takes full advantage of the machine learning module (LWPR kernel) to abstract an optimized representation of the sensorimotor space while the cerebellar component integrates this to generate corrective terms in the framework of a control task. Furthermore, we illustrate how the use of a simple adaptive error feedback term allows to use the proposed architecture even in the absence of an accurate analytic reference model. The presented approach achieves an accurate control with low gain corrective terms (for compliant control schemes). We evaluate the contribution of the different components of the proposed scheme comparing the obtained performance with alternative approaches. Then, we show that the presented architecture can be used for accurate manipulation of different objects when their physical properties are not directly known by the controller. We evaluate how the scheme scales for simulated plants of high Degrees of Freedom (7-DOFs).

La explicación: Su naturaleza psicológica y su papel en la investigación científica

Customarily explanations in scientific situations are envisaged as a process of depart¬mg from events investigated to move toward abstractive constructions. The standard and most appealling procedure is to symbolize and mathematize events. Essentially, explana¬tion is regarded as very different from description of events.By confrast, to grant the necessity of clinging to events, explanation is simply a more analytic reference to things and events than ordinary description, but still explanation is esentially description. While maintaining contact with events, explanation connists of relating things and events ixt a more elaborate way than superficial examination.Because of the prominent place of linguistics and symbolic factors in description and explanation, the role of such features are briefly examined as they contribute to the total process in science and common affairs.

Predicting the Solubility of the Sparingly Soluble Solids 1,2,4,5-Tetramethylbenzene, Phenanthrene, and Fluorene in Various Organic Solvents by Molecular Simulation

We present a simple method to estimate the solubility of weakly soluble solids in different solvents. The method involves the calculation of the residual chemical potential of a single solute molecule in the solvent of interest using an appropriate atomistic free energy simulation technique. In the present method, an expanded ensemble calculation is used, along with a combined Wang−Landau/Bennett's acceptance ratio method. To avoid the simulation of the solid phase and the use of analytic reference states, a single experimental solubility data point for the solute in a single reference solvent is also required. The method has advantages over more empirical descriptor-based methods in that the simulations enable insight into the underlying molecular driving forces responsible for solubility trends. Results are presented for the solubility of 1,2,4,5-tetramethylbenzene, phenanthrene, and fluorene in the solvents hexane, octane, ethanol, 1-octanol, cyclohexane, benzene, and 1,4-dioxane. Overall, agreement be...

Iterative learning-based decentralized adaptive tracker for large-scale systems: A digital redesign approach

In this paper, a digital redesign methodology of the iterative learning-based decentralized adaptive tracker is proposed to improve the dynamic performance of sampled-data linear large-scale control systems consisting of N interconnected multi-input multi-output subsystems, so that the system output will follow any trajectory which may not be presented by the analytic reference model initially. To overcome the interference of each sub-system and simplify the controller design, the proposed model reference decentralized adaptive control scheme constructs a decoupled well-designed reference model first. Then, according to the well-designed model, this paper develops a digital decentralized adaptive tracker based on the optimal analog control and prediction-based digital redesign technique for the sampled-data large-scale coupling system. In order to enhance the tracking performance of the digital tracker at specified sampling instants, we apply the iterative learning control (ILC) to train the control input via continual learning. As a result, the proposed iterative learning-based decentralized adaptive tracker not only has robust closed-loop decoupled property but also possesses good tracking performance at both transient and steady state. Besides, evolutionary programming is applied to search for a good learning gain to speed up the learning process of ILC.

Adaptive path following controller of underactuated ships using serret-frenet frame

This paper presents an adaptive path following control law to steer underactuated ships along a predefined path at a constant forward speed with uncertain parameters due to changes of added mass matrices. The proposed controller is based on analytic model predictive control and model reference adaptive control. The Serret-Frenet frame is used to describe the ship dynamics. The analytic model predictive control provides a systematic method rather than try-and-error method to get appropriate control parameters to guarantee the stability of the closed-loop system, and the well-defined relative degree is guaranteed by introducing output-redefinition. An identification algorithm based on model reference adaptive control is used to identify the uncertain parameters. Numerical simulations are provided to demonstrate the validity of the proposed control law.

Digital redesign of the decentralised adaptive tracker for linear large-scale systems

A novel digital redesign of the analogue model-reference-based decentralized adaptive tracker is proposed for the sampled-data large scale system consisting of N interconnected linear subsystems, so that the system output will follow any trajectory specified at sampling instant which may not be presented by the analytic reference initially, and shows that the proposed decentralized controller induces a good robustness on the decoupling of the closed-loop controlled system. The adaptation of the analogue controller gain is derived by using the model-reference adaptive control theory based on Lyapunov's method. In this article, it is shown that using the sampled-data decentralized adaptive control system it is theoretically possible to asymptotically track the desired output with a desired performance. It is assumed that all the controllers share their prior information and the principal result is derived when they cooperate implicitly. Based on the prediction-based digital redesign methodology, the optimal digital redesigned tracker for the sampled-data decentralised adaptive control systems is newly proposed. An illustrative example of interconnected linear system is presented to demonstrate the effectiveness of the proposed design methodology.

Weighted LBF for spaceborne general bistatic SAR processing

Loffeld’s bistatic formula (LBF) is the first two-dimensional analytic point target reference spectrum derived for general bistatic SAR frequency domain focusing. The phase history is expanded in Taylor series around the individual points of stationary phase of the transmitter-target and target-receiver phase histories, respectively, and thus the common bistatic stationary phase point can be obtained using the method of stationary phase. Unfortunately, it shows limitations for extreme bistatic configurations, namely the highly squinted mode and space-surface application. The weighted LBF (WLBF) is proposed in this paper based on the different contributions of total phase modulation from the transmitter and receiver. The formulae we derived are compared with that of the original literature. The extreme bistatic stripmap SAR data can be focused using WLBF, which accommodates the spaceborne squint geometry using the modified effective velocity solution. A point target simulation example is presented to verify the accuracy of the new WLBF spectrum.