Hasil untuk "Analysis"

Menampilkan 20 dari ~2809580 hasil · dari DOAJ, arXiv

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arXiv Open Access 2026
Foundations for Agentic AI Investigations from the Forensic Analysis of OpenClaw

Jan Gruber, Jan-Niclas Hilgert

Agentic Al systems are increasingly deployed as personal assistants and are likely to become a common object of digital investigations. However, little is known about how their internal state and actions can be reconstructed during forensic analysis. Despite growing popularity, systematic forensic approaches for such systems remain largely unexplored. This paper presents an empirical study of OpenClaw a widely used single-agent assistant. We examine OpenClaw's technical design via static code analysis and apply differential forensic analysis to identify recoverable traces across stages of the agent interaction loop. We classify and correlate these traces to assess their investigative value in a systematic way. Based on these observations, we propose an agent artifact taxonomy that captures recurring investigative patterns. Finally, we highlight a foundational challenge for agentic Al forensics: agent-mediated execution introduces an additional layer of abstraction and substantial nondeterminism in trace generation. The large language model (LLM), the execution environment, and the evolving context can influence tool choice and state transitions in ways that are largely absent from rule-based software. Overall, our results provide an initial foundation for the systematic investigation of agentic Al and outline implications for digital forensic practice and future research.

en cs.CR, cs.AI
DOAJ Open Access 2025
Standardisation of bioimpedance assessment in young children: a feasibility study of home-based body composition measurement in Danish two-year-olds

Clara Barfod Parellada, Leigh C. Ward, Anne Mette Skovgaard et al.

Objective: Body composition takes a key position in monitoring obesity risk in children. Bioelectrical impedance analysis (BIA) offers a promising, non-invasive method, suitable for field use and young children. However, existing BIA protocols are not tailored to this age group, leaving a knowledge gap on procedures feasible and acceptable to children, parents, and health professionals. This study aimed to develop and assess the feasibility of implementing a standardised protocol for BIA measurements in young children. Methods: The settings of community health nurses (CHNs) in Denmark were used to develop a standardised protocol for BIA measurements of two-year-old children (January 2022–March 2025). Feasibility was evaluated in a community-based sample of 72 children, evaluating suitability, practicality, adaptation, resources, and acceptability. Results: The BIA protocol was developed through an iterative process exploring the children's reactions and cooperation during assessments. The final protocol was tested on 70 children (mean age 24.21 ± 1.21 months). A total of 50 children (71 %) completed the BIA measurements. CHNs reported the procedures as feasible, though challenges included child cooperation, equipment availability, and technical difficulties. Most parents (96 %) found procedures acceptable, and 79 % perceived their child accepted them. Conclusions: This first study to develop and test a standardised BIA protocol tailored young children, demonstrates feasibility in home settings and high acceptability among parents, children, and CHNs. Although no normative BIA data exists for young children, our findings support the potential for integrating body composition monitoring into community-based early obesity prevention programmes, conditioning developmentally appropriate assessment and training health professionals.

DOAJ Open Access 2025
Cigarette Smoke Exposure Leads to Organic and Mineral Bone Component Changes: The Importance of Rho Kinase Function in These Events

Alex Ferreira da Silva, Franciele Jesus Lima, Alyne Riani Moreira et al.

Aberrant Rho-associated kinase function could be associated with increased bone fragility. Since cigarette smoke (CS) exposure promotes the increase in bone fragility due to changes in bone tissue components, this study aimed to investigate how CS exposure could modulate the Rho kinase-associated bone structural changes. Mice were assigned to four groups: control; smoke; control with Rho kinase inhibitor administration; and smoke with a Rho kinase inhibitor. Bone samples were obtained to assess bone histomorphometry analysis, type I collagen composition, and MEPE expression in trabeculae. We observed that CS exposure induced decreased trabecular and osteoid thickness. A concomitant increase in the osteoclastic and erosion surfaces and a decrease in the mineralization surface were observed. Additionally, CS exposure decreased the type I collagen and MEPE expression. Rho kinase inhibitor administration recovered the bone mineralization and the collagen type I deposition. Conclusions: CS exposure increases Rho kinase activity in bone cells, leading to structural changes. The administration of a Rho GTPases inhibitor partially reverses these effects, likely due to the recovery in osteoblast activity.

DOAJ Open Access 2025
Effects of light intensity on erythrophore number and astaxanthin amount in the skin of coral trout Plectropomus leopardus

Nannan Zhao, Jin Gao, Shuyuan Fu et al.

Numerous studies have reported that environmental background color alters the skin color of aquaculture fish. In the present study, we investigated the effects of light intensity on skin coloration, chromatophores numbers, astaxanthin content and gene expression in 7-month-old coral trout Plectropomus leopardus. After been feeding astaxanthin-free diet (AFD) for 30 days, the fish in control group (under natural light) showed little change in skin color. In contrast, the skin color of fish in light-treat group (under 300 lux white light) changed from dark-brown to orange-red, associated with erythrophores number increase, xanhtrophores number reduction and astaxanthin amount increase on the skin. Transcriptomic analysis indicated that several genes related to carotenoid transport, metabolism, cell apoptosis and autophagy show significant variation between the light-treat and control groups. These results suggest that background light intensity affect the proliferation of erythrophores and the acquisition of astaxanthin in the skin of coral trout.

Aquaculture. Fisheries. Angling
arXiv Open Access 2025
Voltage-sensitive distribution factors for contingency analysis and topology optimization

Maurizio Titz, Dirk Witthaut, Joost van Dijk et al.

Topology optimization is a promising approach for mitigating congestion and managing changing grid conditions, but it is computationally challenging and requires approximations. Conventional distribution factors like PTDFs and LODFs, based on DC power flow, fail to capture voltage variations, reactive power, and losses, thereby limiting their use in detailed optimization tasks such as busbar splitting. This paper introduces generalized distribution factors derived from a voltage-sensitive linearization of the full AC power flow equations. The proposed formulation accurately reflects reactive power flows, Ohmic losses, and voltage deviations while remaining computationally efficient. We derive and evaluate generalized PTDFs, LODFs, and topology modification factors using matrix identities. We discuss potential applications including voltage-aware N-1 security analysis and topology optimization with a focus on busbar splitting. Numerical experiments demonstrate close agreement with full AC solutions, significantly outperforming the traditional DC approximation.

en math.OC, eess.SY
DOAJ Open Access 2024
Research on automatic roadway formation and surrounding rock stability control technology by roof cutting and pressure relief in Qianyingzi Coal Mine

Aiguo SUN, Haitao LI, Xuezheng CHENG et al.

According to the engineering geological characteristics and production technology level of Qianyingzi Coal Mine, the stability control technology of surrounding rock of the cutting roof and pressure relief roadway is proposed. For the advanced section, lagging section and stable section of the mining roadway, technical measures of advanced reinforcement support, side wall protection and lagging temporary support were proposed. Through the real-time monitoring system, the stress of anchor cable and surrounding rock deformation of goaf roadway are monitored, the deformation characteristics of roadway and stope surrounding rock are studied, and the law of mine pressure development in self-formed roadway without coal pillar is revealed by the comparison and analysis with the existing goaf roadway. The results show that the deformation rate of surrounding rock reaches the maximum at the position of 170 m away from the working face, and the deformation of surrounding rock is the most intense at this stage, and then tends to be gentle, and the deformation of surrounding rock reaches the stable stage when the working face lags 220 m. The application effect of the pre-cracking blasting cutting roof for gob-side entry retaining in the W3233 working face of Qianyingzi Coal Mine has reached the expected goal.

Mining engineering. Metallurgy
DOAJ Open Access 2024
Performance and farmers preferred traits of Jersey × local cows in the tropics: the case of Angolelana Tera district, North Shewa zone, Ethiopia

Abebe Bereda, Beshah Agune, Zelalem Yilma

The objectives of this research were to assess the productive and reproductive performances, and crossbred Jersey farmers preferences traits in Angolelana Tera district, Amhara region, Ethiopia. A total of 158 smallholders holding Jersey crossbreed recruited from seven Kebeles were interviewed face to face using a semi structured questionnaire. Index for traits preferences and one-way analysis of variance for reproductive and productive performances differences of dairy cattle breeds were employed using Statistical Package for Social Science (SPSS) version 25. Milk yield, growth and traction in Holstein-Friesian crossbred, while milk fat, fertility and growth in Jersey crossbred, and disease’s resistant ability, traction power and adaptation to local climates in indigenous breed were the most valued traits by farmers in the study district. The overall mean of the most reproductive and productive performance parameters of Jersey crossbred namely age at first calving (30.56 months), lactation length (241.32 days), calving interval (441.79 days), number of services per conception (1.55) and longevity (16.53 years) were significantly better than its counterpart Holstein-Friesian crossbreed with the corresponding values of 32.91 months, 227.28 days, 447.59 days, 1.86 and 15.03 years, respectively. However, no significant variations were observed between the two crossbreeds of Holstein-Friesian and Jersey on age at first service and days open in the present study. Generally, indigenous breeds significantly lower productive and reproductive performances than crossbred cattle. In conclusion, although some parameters are antagonistic with the standards recommended for modern dairy farming, Jersey crossbreed performed well in the district. These indicates that the project looks targeted on the right breed in the right place with necessary training approaches on caring of crossbred Jersey breed and milk processing. Therefore, the wide use of Jersey crossbreed must be promoted in the district together with necessary improved management packages.

Social Sciences
DOAJ Open Access 2024
Genetic diversity in pointed gourd (Trichosanthes dioica) genotypes for fruit yield and quality traits under eastern plateau and hill region

ANKIT KUMAR SINHA, BHAVANA P, A K SINGH et al.

The experiment was conducted during summer seasons of 2021–22 and 2022–2023 at ICAR-Research Complex for Eastern Region, Farming System Research Centre for Hill and Plateau Region, Plandu, Ranchi, Jharkhand focused on assessing the genetic diversity for fruit yield and quality parameters among 46 unique pointed gourd (Trichosanthes dioica Roxb.) genotypes. The data collected underwent thorough statistical analyses, encompassing genetic variability, analysis of variance (ANOVA), correlation coefficients, path analysis, exploration of genetic divergence and biochemical characterization. The ANOVA results revealed significant variations across the selected genotypes in terms of fruit yield and quality traits. Key attributes, such as the number of fruits/plant, harvest frequency, pulp seed ratio and total phenol content, displayed significant positive correlations with total fruit yield. The noteworthy was the positive direct effect of pulp weight on total fruit yield indicated by a coefficient of 0.99. Further, this study identified total fruit yield as the primary contributor to the observed genetic diversity. Cluster analysis results in to the grouping of 46 genotypes into 12 distinct clusters based on D2 values. The study highlighted significant variability among pointed gourd genotypes, suggesting ample opportunities for selection-based improvement. Selection based on characteristics such as the number of fruits per plant, pulp weight and pulp seed ratio is expected to enhance yield potential. Identified genotypes, such as Swarna Alaukik, HAP-79, HAP-70 (for yield-related attributes) and HAP-106 (for quality traits), emerged as promising which hold potential for future breeding initiatives and are recommended for cultivation in the eastern plateau and hill region for augmenting yield potential. Cluster III and cluster XII offer diverse genetics for breeding. Crossing these clusters can create new high-yield cultivars. This strategic cultivation aims to enhance the nutritional well-being of the local population in that area.

DOAJ Open Access 2024
Estimation and Characteristics of Low-Frequency Ambient Sea Noise from Far-Field Ships

Xuegang Li, Yang Shi, Cheng Zhao et al.

To study the rapid estimation method and characteristics of low-frequency ambient sea noise generated by far-field ships, firstly, based on the reciprocity principle of sound fields and the fact that the number of noise sources significantly exceeds the number of receiving array elements, the positions of noise sources and receiving array elements were swapped to effectively reduce the sound field estimates and the running time. Secondly, a vertical directionality analysis method for ambient noise generated by ship noise was derived. And lastly, the ambient sea noise generated by ship noise in the Philippine Sea was estimated and analyzed, and the validity of the estimation method was verified based on measured data in the region. The estimation method presented in this paper can be used to predict the level and directionality of ambient noise generated by ship noise in a large area of sea, and acts as technical support for the meaningful use of sonar arrays in the actual marine environment.

Naval architecture. Shipbuilding. Marine engineering, Oceanography
DOAJ Open Access 2024
Canopy Structural Changes in Black Pine Trees Affected by Pine Processionary Moth Using Drone-Derived Data

Darío Domingo, Cristina Gómez, Francisco Mauro et al.

Pine species are a key social and economic component in Mediterranean ecosystems, where insect defoliations can have far-reaching consequences. This study aims to quantify the impact of pine processionary moth (PPM) on canopy structures, examining its evolution over time at the individual tree level using high-density drone LiDAR-derived point clouds. Focusing on 33 individuals of black pine (<i>Pinus nigra)</i>—a species highly susceptible to PPM defoliation in the Mediterranean environment—bitemporal LiDAR scans were conducted to capture the onset and end of the major PPM feeding period in winter. Canopy crown delineation performed manually was compared with LiDAR-based methods. Canopy metrics from point clouds were computed for trees exhibiting contrasting levels of defoliation. The structural differences between non-defoliated and defoliated trees were assessed by employing parametric statistical comparisons, including analysis of variance along with post hoc tests. Our analysis aimed to distinguish structural changes resulting from PPM defoliation during the winter feeding period. Outcomes revealed substantive alterations in canopy cover, with an average reduction of 22.92% in the leaf area index for defoliated trees, accompanied by a significant increase in the number of returns in lower tree crown branches. Evident variations in canopy density were observed throughout the feeding period, enabling the identification of two to three change classes using LiDAR-derived canopy density metrics. Manual and LiDAR-based crown delineations exhibited minimal differences in computed canopy LiDAR metrics, showcasing the potential of LiDAR delineations for broader applications. PPM infestations induced noteworthy modifications in canopy morphology, affecting key structural parameters. Drone LiDAR data emerged as a comprehensive tool for quantifying these transformations. This study underscores the significance of remote sensing approaches in monitoring insect disturbances and their impacts on forest ecosystems.

Motor vehicles. Aeronautics. Astronautics
arXiv Open Access 2024
Understanding data analysis aspects of TMS-EEG in clinical study: a mini review and a case study with open dataset

Hua Cheng

Concurrency of transcranial magnetic stimulation with electroencephalography (TMS-EEG) technique is a powerful and challenging methodology for basic research and clinical applications. Aspects considered in experiments for effective TMS-EEG recordings and analysis, including artifact management, data analysis and interpretation and protocols. mini review offers an extensive insight of TMS-EEG methodology in experimental and computational procedures. Case study aims to leverage an openly available, high-quality EEG dataset to delve into the alterations in cortical activity. By applying Intermittent theta-burst stimulation (iTBS) and continuous theta-burst stimulation (cTBS) to the left dorsolateral prefrontal cortex (DLPFC) in healthy individuals, we observe changes in oscillatory patterns within the EEG data. The dataset includes meticulously extracted resting-state EEG recordings, TMS-evoked potential data, and MRI scans. To process these data, we utilized Brainstorm, an open-source Matlab application, which facilitated noise reduction through independent component analysis and signal-space projection techniques. It allowed us to identify, visualize, and analyze TMS-evoked potentials (TEPs) and TMS-induced oscillations (TIOs). In addition, the study presents detailed plots of resting-state EEG power, local mean field power (LMFP), TMS-related spectral perturbation (TSRP), and inter-trial phase clustering (ITPC). Paired t-tests and cluster-based permutation tests have been performed for statistical analysis. The wealth and quality of this dataset make it ideal for examining the neuromodulatory impact of TBS on the prefrontal cortex. Brainstorm's extensive feature set greatly supports the exploration of such neurological data. Future research directions could concentrate on conducting source localization analyses and comparative group studies.

en q-bio.NC
arXiv Open Access 2024
Wave packet analysis of semigroups generated by quadratic differential operators

S. Ivan Trapasso

We perform a phase space analysis of evolution equations associated with the Weyl quantization $q^{\mathrm{w}}$ of a complex quadratic form $q$ on $\mathbb{R}^{2d}$ with non-positive real part. In particular, we obtain pointwise bounds for the matrix coefficients of the Gabor wave packet decomposition of the generated semigroup $e^{tq^{\mathrm{w}}}$ if $\mathrm{Re} (q) \le 0$ and the companion singular space associated is trivial. This result is then leveraged to achieve a comprehensive analysis of the phase regularity of $e^{tq^{\mathrm{w}}}$ with $\mathrm{Re} (q) \le 0$, thereby extending the $L^2$ analysis of quadratic semigroups initiated by Hitrik and Pravda-Starov to general modulation spaces $M^p(\mathbb{R}^d)$, $1 \le p \le \infty$, with optimal explicit bounds.

en math.AP, math.FA
DOAJ Open Access 2023
The Development of a Secure Internet Protocol (IP) Network Based on Asterisk Private Branch Exchange (PBX)

Mubarak Yakubova, Olga Manankova, Assel Mukasheva et al.

The research problem described in this article is related to the security of an IP network that is set up between two cities using hosting. The network is used for transmitting telephone traffic between servers located in Germany and the Netherlands. The concern is that with the increasing adoption of IP telephony worldwide, the network might be vulnerable to hacking and unauthorized access, posing a threat to the privacy and security of the transmitted information. This article proposes a solution to address the security concerns of the IP network. After conducting an experiment and establishing a connection between the two servers using the WireShark sniffer, a dump of real traffic between the servers was obtained. Upon analysis, a vulnerability in the network was identified, which could potentially be exploited by malicious actors. To enhance the security of the network, this article suggests the implementation of the Transport Layer Security (TLS) protocol. TLS is a cryptographic protocol that provides secure communication over a computer network, ensuring data confidentiality and integrity during transmission. Integrating TLS into the network infrastructure, will protect the telephone traffic and prevent unauthorized access and eavesdropping.

Technology, Engineering (General). Civil engineering (General)
DOAJ Open Access 2023
Toward an integrated approach for mental health and psychosocial support and peacebuilding in North-East Nigeria: programme description and preliminary outcomes from ‘Counselling on Wheels’

Sharli Paphitis, Fatima Akilu, Natasha Chilambo et al.

Background Despite theoretical support for including mental health and psychosocial support (MHPSS) with peacebuilding, few programmes in conflict-affected regions fully integrate these approaches. Aims To describe and assess preliminary outcomes of the Counselling on Wheels programme delivered by the NEEM Foundation in the Borno State of North-East Nigeria. Method We first describe the components of the Counselling on Wheels programme, including education and advocacy for peace and social cohesion through community peacebuilding partnerships and activities, and an MHPSS intervention open to all adults, delivered in groups of eight to ten people. We then conducted secondary analysis of data from 1550 adults who took part in the MHPSS intervention, who provided data at baseline and 1–2 weeks after the final group session. Vulnerability to violent extremism was assessed with a locally developed 80-item scale. Symptoms of common mental disorders were assessed with the Depression, Anxiety and Stress Scale (DASS-21) and Post-Traumatic Stress Disorder Scale (PTSD-8). Data were analysed through a mixed-effect linear regression model, accounting for clustering by community and adjusted for age and gender. Results After taking part in group MHPSS, scores fell for depression (−5.8, 95% CI −6.7 to −5.0), stress (−5.5, 95% CI −6.3 to −4.6), post-traumatic stress disorder (−2.9, 95% CI −3.4 to −2.4) and vulnerability to violent extremism (−44.6, 95% CI −50.6 to −38.6). Conclusions The Counselling on Wheels programme shows promise as a model for integrating MHPSS with community peacebuilding activities in this conflict-affected region of Africa.

arXiv Open Access 2023
Convergence analysis of Laguerre approximations for analytic functions

Haiyong Wang

Laguerre spectral approximations play an important role in the development of efficient algorithms for problems in unbounded domains. In this paper, we present a comprehensive convergence rate analysis of Laguerre spectral approximations for analytic functions. By exploiting contour integral techniques from complex analysis, we prove that Laguerre projection and interpolation methods of degree $n$ converge at the root-exponential rate $O(\exp(-2ρ\sqrt{n}))$ with $ρ>0$ when the underlying function is analytic inside and on a parabola with focus at the origin and vertex at $z=-ρ^2$. As far as we know, this is the first rigorous proof of root-exponential convergence of Laguerre approximations for analytic functions. Several important applications of our analysis are also discussed, including Laguerre spectral differentiations, Gauss-Laguerre quadrature rules, the scaling factor and the Weeks method for the inversion of Laplace transform, and some sharp convergence rate estimates are derived. Numerical experiments are presented to verify the theoretical results.

en math.NA, math.CA
DOAJ Open Access 2022
Phytochemical, Proximate and Mineral Composition, Antioxidant and Antidiabetic Properties Evaluation and Comparison of Mistletoe Leaves from Moringa and Kolanut Trees

Olugbenga David Oloruntola, Simeon Olugbenga Ayodele

This study evaluates the chemical properties of mistletoe leaves powder from moringa trees (MLPM) and mistletoe leaves powder from kola nut trees (MLPK). The MLPM and MLPK were subjected to phytochemical analysis, vitamin A determination, lipid peroxidation inhibition activity, 2, 2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) analysis, proximate and mineral composition analysis, alpha-amylase inhibitory activity and alpha-glucosidase inhibitory activity. Total phenol, steroids, and tannins concentrations were higher in MLPK than in MLPM; steroids was higher in MLPK than in MLPM; whereas total flavonoids and saponins concentrations, were equivalents. MLPK had greater vitamin A concentrations and DPPH than MLPM. The lipid peroxidation inhibition of MLPM and MLPK did not differ significantly. MLPM had higher moisture, crude fibre, and ash content than MLPK. Furthermore, MLPK had larger fat, crude protein, and nitrogen-free extract contents than MLPM. The MLPM and MLPK have similar Zn (0.9 vs. 1.3 mg/kg), Ca (20.1 vs. 13.1 mg/kg), Mg (66.1 vs. 70.2 mg/kg), and P (185.8 vs. 183.5 mg/kg) contents. The alpha-amylase inhibitory action of MLPM (40.40%) and MLPK (35.07%) were similar. MLPK (44.37%), on the other hand, has a stronger alpha-glucose inhibitory action than MLPM (32.47%). Finally, phenol, steroids, tannins, and steroids varied between MLPM and MLPK, with phenol, steroids, and tannins being greater in MLPK. The MLPM had higher vitamin A concentrations and antioxidant activity than MLPK. The MLPM and MLPK inhibited alpha-amylase and alpha-glucosidase activity.

Agriculture, Agriculture (General)
DOAJ Open Access 2022
Identifying strawberry DOF family transcription factors and their expressions in response to crown rot

Chun LUO, Yuyang HU, Bo SHU

Crown rot is one of the most destructive diseases of cultivated strawberry. The DOF family transcription factors, which involved in biotic stress, has not been studied in responding to strawberry crown rot. In this study, the DOFs of Fragaria × ananassa, F. iinumae, F. nilgerrensis, F. viridis, and F. vesca were characterized. One hundred and eighteen FaDOFs, twenty-two FiDOFs, twenty-three FnDOFs, twenty-five FviDOFs and thirty-seven FvDOFs were identified. Gene cluster analysis showed nearly seventy segmental duplication and seventeen tandem duplications for DOF family expansion in octaploid strawberry. In addition, 59 FaDOFs showed syntenic relationships with 32 AtDOFs, which were located on all F.×ananassa chromosomes except Fvb4-1 and Fvb4-2. Except for five DOFs of diploid strawberries had syntenic relationships to one FaDOF, most of them corresponded to multiple FaDOFs. Gene expression analysis revealed that 107 FaDOFs were expressed in crown, and most of them were downregulated by crown rot, while some FaDOFs such as FaDOF107, 12, 82, 91, 90 and 101 were upregulated, whose regulation was not always consistent with the cis-elements in their promoters. Together, these results provided a basis for further functional studies of the FaDOFs.

Forestry, Agriculture (General)
DOAJ Open Access 2022
Observer-Based Robust Finite-Time Trajectory Tracking Control for a Stratospheric Satellite Subject to External Disturbance and Actuator Saturation

Shurui Huang, Yueneng Yang, Ye Yan et al.

The stratospheric satellite is regarded as an ideal stratosphere flight platform and is able to accomplish various missions such as surveillance, earth observation, and remote sensing, which requires a robust and effective trajectory tracking control method to support these tasks. A novel observer-based robust finite-time control scheme is proposed to address the trajectory tracking control problem dedicated to a stratospheric satellite in the presence of external disturbance and actuator saturation. Firstly, an extended state observer (ESO) is adopted to observe the unavailable velocity states and unknown disturbances simultaneously, and the estimated data are utilized in the robust control law design. Then, an auxiliary system based on anti-windup compensator is developed to directly compensate for the actuator saturation difference. After that, a backstepping nonsingular fast terminal sliding mode control (BNFTSMC) strategy is designed to track the desired trajectory with high accuracy, fast convergence rate, and finite-time convergence. Then, a stability analysis using Lyapunov-based theory is performed, in which the stabilization of the stratospheric satellite system and finite-time convergence are proven. Furthermore, a number of simulations are conducted further to verify the excellent performance of the designed control strategy.

Motor vehicles. Aeronautics. Astronautics
arXiv Open Access 2022
Basics of Fourier Analysis for High-Energy Astronomy

T. M. Belloni, D. Bhattacharya

The analysis of time variability, whether fast variations on time scales well below the second or slow changes over years, is becoming more and more important in high-energy astronomy. Many sophisticated tools are available for data analysis and complex practical aspects are described in technical papers. Here, we present the basic concepts upon which all these techniques are based. It is intended as a condensed primer of Fourier analysis, dealing with fundamental aspects that can be examined in detailed elsewhere. It is not intended to be a presentation of detailed Fourier tools for data analysis, but the reader will find the theoretical basis to understand available analysis techniques.

en astro-ph.IM
arXiv Open Access 2022
Bugs as Features (Part I): Concepts and Foundations for the Compositional Data Analysis of the Microbiome-Gut-Brain Axis

Thomaz F. S. Bastiaanssen, Thomas P. Quinn, Amy Loughman

There has been a growing acknowledgement of the involvement of the gut microbiome - the collection of microbes that reside in our gut - in regulating our mood and behaviour. This phenomenon is referred to as the microbiome-gut-brain axis. While our techniques to measure the presence and abundance of these microbes have been steadily improving, the analysis of microbiome data is non-trivial. Here, we present a perspective on the concepts and foundations of data analysis and interpretation of microbiome experiments with a focus on the microbiome-gut-brain axis domain. We give an overview of foundational considerations prior to commencing analysis alongside the core microbiome analysis approaches of alpha diversity, beta diversity, differential feature abundance and functional inference. We emphasize the compositional data analysis (CoDA) paradigm. Further, this perspective features an extensive and heavily annotated microbiome analysis in R in the supplementary materials, as a resource for new and experienced bioinformaticians alike.

en q-bio.GN, stat.AP

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