Constellation Analysis Research Articles

Performance analysis of Hexagonal QAM constellations on quadrature spatial modulation with perfect and imperfect channel estimation

In this study, the quadrature spatial modulation (QSM) technique, which is a rational multiple-input multiple-output (MIMO) transmission technique and frequently encountered in recent studies in the literature, and the hexagonal quadrature amplitude modulation (HQAM) constellation technique, which combines symbols in an “optimum” way are combined. This new MIMO scheme has been named by the authors as HQAM-QSM. Also, the impact of imperfect channel knowledge on the performance of the proposed scheme is examined. The HQAM constellation technique is a technique that provides better results under the same power assumption than the conventional QAM constellation in terms of symbol separation and is more often encountered when it comes to energy-efficiency. Due to the nature of HQAM symbols, error-floor occurs when the QSM system is applied. Hence, the optimum angle is obtained by rotating the HQAM symbols. With this optimum angle, it has been seen that the error-floor disappeared and the performance of the system is improved. Besides, the HQAM technique performs similar bit error rates (BER) to QAM at high signal-to-noise ratio (SNR) values. From this point forth, in our study, the rational HQAM-QSM technique, which uses energy-efficient HQAM symbols instead of traditional modulated QAM symbols and also carries information effectively on two active antennas, is proposed. Performance analysis of the HQAM-QSM technique is performed on Rayleigh fading channels.

Сomparative study of the accuracy of Earth observation by satellite constellations in high elliptical orbits

The paper provides results of estimated accuracy comparisons for applied satellite constellations (ASC) in Molniya-type high elliptical orbits based on a previously presented criterion for analysis of accuracy parameters of ASC that observe targets on the Earth surface and/or in the layer above the surface, which is not dependent on specific features of the onboard equipment, but rather on the structure and dynamics of the ASC. The paper provides an algorithm for numerical simulations of ASC. The paper discusses accuracy parameters for ASC in high elliptical orbits in various orbital configurations, as well as a combined option involving spacecraft in geostationary orbit. It defines key trajectory design parameters driving the ASC accuracy. The results can be used for selecting the initial ASC configuration in high elliptical orbits during preliminary design phase. Key words: observation satellite systems, high elliptical orbits, accuracy criterion, satellite constellation analysis.

COMPARATIVE STUDY OF THE ACCURACY OF EARTH OBSERVATION BY SATELLITE CONSTELLATIONS IN HIGH ELLIPTICAL ORBITS

The paper provides results of estimated accuracy comparisons for applied satellite constellations (ASC) in Molniya-type high elliptical orbits based on a previously presented criterion for analysis of accuracy parameters of ASC that observe targets on the Earth surface and/or in the layer above the surface, which is not dependent on specific features of the onboard equipment, but rather on the structure and dynamics of the ASC. The paper provides an algorithm for numerical simulations of ASC. The paper discusses accuracy parameters for ASC in high elliptical orbits in various orbital configurations, as well as a combined option involving spacecraft in geostationary orbit. It defines key trajectory design parameters driving the ASC accuracy. The results can be used for selecting the initial ASC configuration in high elliptical orbits during preliminary design phase. Key words: observation satellite systems, high elliptical orbits, accuracy criterion, satellite constellation analysis.

Design and Analysis of CubeSat Microwave Radiometer Constellations to Observe Temporal Variability of the Atmosphere

Passive microwave satellite observations provide critical information for global forecast models, particularly in cloudy and/or precipitating conditions. The limited temporal sampling provided by current operational polar orbiters cannot capture rapidly changing conditions such as the development of convective storms. This is a significant issue for open-ocean weather systems such as tropical cyclones and hurricanes that can only be effectively monitored from satellites. The recent development and demonstration of miniaturized microwave radiometers on-board low-cost CubeSat satellites has the potential to dramatically improve the temporal and spatial sampling of all-sky microwave observations by deploying a substantial constellation of satellites in low Earth orbit. Two constellations of 60 CubeSats in 550 km orbits are compared to the current operational microwave sensors. One approach employs all polar orbiters, while the other approach uses multiple inclination orbits for increased sampling over convective storm regions. Both approaches reduce average revisit times to approximately ~20-30 minutes globally, and the multi-inclination approach also provides irregular 5-10 minute sampling over selected latitudes. Improved global temporal sampling would provide all-sky observations to global forecast models over rapidly-changing environments, while millimeter-wave observations over convective storm regions would be valuable for both forecasting and studying the development of convective storms. This study demonstrated that a constellation of low-cost CubeSats with microwave radiometers has the potential to provide equivalent temporal resolution to that observed from sensors on geostationary orbit.

Axiological constellations in literary response writing: Critical SFL praxis in an ELA classroom

To engage in critical praxis, teachers of literary response writing need concepts and methods for understanding the efficacy of teaching practices in helping students develop particular dispositions towards texts and the social issues they represent. In this article, the author uses concepts from Legitimation Code Theory (LCT) and Systemic Functional Linguistics (SFL) to reveal the value positions constructed by 8th grade English language arts (ELA) students in essays produced in a critical literary analysis unit. After reading excerpts from two Harry Potter novels, students compared the main characters’ views on elvish enslavement as evidenced by the passages. This study uses axiological constellation analysis to explore the language choices in essays that constructed contrasting stances towards Harry’s character and the representation of elvish enslavement in the texts. The study contributes to understanding how values are constructed in literary response writing and how these relate to broader sociopolitical discourses, with implications for critical praxis in subject English education.

Agro‐morphological and phenotypic variability of sweet basil genotypes for breeding purposes

AbstractThe genus Ocimum is very complicated due to the presence of huge morphological variability along with genetic diversity. Basil (Ocimum basilicum L.) has pharmacological properties to treat headaches, coughs, diarrhea, constipation, warts, worms, and kidney malfunction and potential as a therapeutic agent in treating various age‐related diseases. In this study, a total of 74 genotypes were used in 2017 and 61 genotypes were adapted. Among the 61 genotypes, 50 genotypes were sown in 2018. The present investigation composed of basil genotypes was undertaken to characterize the genotypes based on morphological and phenological features, herbs, and essential oil yield of genotypes. A wide range of variations for traits like days to first cutting (56.92–101.6 d), plant height (13.67–71.90 cm), branch number (3.28–19.43 plant−1), fresh herb yields (12.94–274.11 g plant−1), and essential oil yield (0.04–1.71%) were observed and can be useful for breeding purposes. PI 652070 and PI 296391 were found superior with the highest herbs yield as compared with other genotypes. Overall, PI 358469 and Ames 32309 genotypes exhibited the highest essential oil content. A constellation analysis was conducted to investigate the genetic diversity of basil genotypes. According to the constellation plot analysis, 46 basil genotypes and four cultivars were evaluated according to morphological, yield, and International Association for the Protection of New Plant Varieties (UPOV) properties, and most of the basil genotypes and one cultivar (Midnight) were located in the same group. As a result of the constellation plot analysis, Moonlight and Dino cultivars were located in the same group with PI 141198 (Maryland, USA) and genotypes originated from Georgia, Iran, Afghanistan, Ethiopia, and Hungary located in the same main group. Other genotypes of the same origin were found in a different main group.

Rethinking Suburban Governance in the CEE Region: A Comparison of Two Municipalities in Poland and Lithuania

In this article, we seek to analyse and compare the modalities of suburban governance in Polish and Lithuanian municipalities looking at the territorial development trends typical for the Central Eastern Europe region. The theoretical elaborations on suburban governance are evolving towards the analysis of constellations of diverse actors, institutions and processes that define the politics and design of suburban spaces. We assume that there are similarities and differences in suburban governance in the analysed localities compared to Western countries in terms of networks, actors and territorialisation of local politics. Despite both suburban municipalities showing similarities in suburban development patterns (growing middle-class population, economic capital accumulation, suburban sprawl and interconnectedness with the metropolitan zone), the analysis reveals the main differences in terms of composition and importance of horizontal and vertical networks, the role of local stakeholders and collective action. The article concludes that both localities represent a specific approach to suburban governance marked by low stakeholders’ participation, dependence on the top down vertical state and regional networks and the creation of urban-suburban policies within metropolitan areas.

Exploring actors, their constellations, and roles in digital agricultural innovations

Agricultural innovations can emerge from multi-actor cooperation and so actors, their roles, and their activities will likely influence the character of novel farming practices. Recent studies suggest that such cooperation might be particularly relevant for the digitalization of farming, reflected in the transition from mechanical to data-based agricultural tools and practices, collectively referred to as smart farming technologies (SFT). Here, we aim to understand which actors are involved, the roles they have, and how they contribute to the innovation processes leading to SFT use in farm management. To do so, we selected 6 SFT innovations from different European regions. Timeline and constellation analyses were used to study the actors and their contribution to different phases of the innovation processes. We observed 13 different categories of actors that had three different types of actor roles: developer, supporter, and end-user. We found the highest number of both actor diversity and number of roles during the initiation phase, with a subsequent decrease over the next two phases. Farmers were the only actors who took on all 3 roles, and most actors were supporters. Farmer and IT-experts made up the most common constellation for agricultural apps. Constellations made up of farmers, advisors, and agri-tech actors were the most common in innovative practices dependent on GPS. The divide in the technological complexity and the degree of required learning and change for farmers in SFT innovation processes was reflected by the two innovation categories we studied, namely agricultural apps and in-field practices dependent on GPS. These could therefore constitute a defining difference in how to determine actor constellations in SFT innovation processes.

Isolation and characterization of low pathogenic H7N7 avian influenza virus from a red-crowned crane in a zoo in South Korea

BackgroundSouth Korea conducts annual national surveillance programs to detect avian influenza (AI) in domestic poultry, live bird markets, and wild birds. In March 2017, an AIV was isolated from fecal samples in an outdoor aviary flight cage in a zoo in Korea.ResultsNucleotide sequencing identified the isolate as low pathogenic avian influenza virus (LPAIV) H7N7, and DNA barcoding analysis identified the host species as red-crowned crane. This isolate was designated A/red-crowned crane/Korea/H1026/2017 (H7N7). Genetic analysis and gene constellation analysis revealed that A/red-crowned crane/Korea/H1026/2017 (H7N7) showed high similarity with four H7N7 LPAIVs isolated from wild bird habitats in Seoul and Gyeonggi in early 2017.ConclusionsConsidering the genetic similarity and similar collection dates of the viruses, and the fact that zoo bird cages are vulnerable to AIV, it is likely that fecal contamination from wild birds might have introduced LPAIV H7N7 into the red-crowned crane at the zoo. Therefore, our results emphasize that enhanced biosecurity measures should be employed during the wild bird migration season, and that continued surveillance should be undertaken to prevent potential threats to avian species in zoos and to humans.

It Takes More than Two to Tango: Identifying Roles and Patterns in Multi-Actor Smart Service Innovation

Smart service systems enable innovative value propositions based on smart products and data-driven value creation. Grounded in service-dominant logic as our theoretical lens, we argue that smart service innovation takes place in ecosystems of collaborating actors, as a single actor does not possess all required resources and competencies. We empirically explore smart service innovation using an interview study of 14 experts who were involved in real-world smart service systems engineering projects. As a result, we conceptualize 17 roles that describe the resources and competencies required for smart service innovation at an abstract level. Through the analysis of actor-role constellations in our sample of projects, we further identify four patterns that exhibit different strategic approaches to smart service innovation. Our results advance the theoretical understanding of smart service systems through an empirically grounded systematization of roles, which reflect the resources and competencies required for smart service innovation. With this study, we shed light on the multi-actor and inter-organizational settings of service innovation processes, which have been under-researched so far. Our insights are further helpful for practitioners, who participate in the smart service innovation and who need to analyze their strategic position in service ecosystems.

Madness and spiritualist philosophy of mind: Maine de Biran and A. A. Royer-Collard on a ‘true dualism’

ABSTRACT The exchange between the philosopher Pierre Maine de Biran and the psychiatrist Antoine-Athanase Royer-Collard has been read either as an exemplary case of the influence of philosophy on medicine or as a “dialogue of the deaf” (Braunstein, Broussais et le matérialisme, 47). However, these two readings imply a clear distribution of roles between the philosopher and the doctor. This article instead examines the metaphysical nature of the discussion between the two spiritualists in their aim to establish a ‘true spiritualism’ from a common problem: the nature of madness. Based on a constellation analysis of Biran’s Nouvelles considérations sur les rapports du Physique et du Moral and Royer-Collard’s 1821 lecture on this manuscript, the article shows that both thinkers are concerned with the most appropriate form of dualism, and how it is possible to establish a relationship between the two fundamental aspects of man – the physical and moral – without denaturing each of them. Paradoxically, the analysis makes manifest a reversal of roles: whereas Biran has a static conception of dualism leading to an organic conception of madness, Royer-Collard demands a dynamic dualism that makes it possible to conceive a causal role for the mind in madness.

Worldwide Coverage Mobile Systems for Supra-Smart Cities Communications: Featured Antennas and Design

Current terrestrial mobile communications networks can’t provide worldwide coverage. Satellite communications are expensive, and terminals are large and heavy. Worldwide mobile coverage requires the use of satellites providing an appropriate QoS, including polar regions. The analysis of the potential satellite constellations demonstrates that LEO one is the best solution. A new generation of low cost, small size, lightweight and global mobile coverage LEO satellites is emerging. The main limitation of the terminals is the antenna size factor, and innovative antennas must be developed to meet this goal. This paper investigates the technologies and techniques for designing and developing antennas aimed at LEO satellite communications in Smart Cities and beyond, which are especially beneficial for mobile communications in areas without 4G/5G coverage. The paper focuses on the terrestrial segment and future mobile devices, remarking the design constraints. In this scenario, the paper reviews the most relevant technologies and techniques used to design suitable antennas. The investigation analyses the state-of-the-art and most recent advances in the design of antennas operating in the Ku-band. The main contribution of the authors is a novel antenna design approach based on SIW technology. The antenna features are compared with other approaches, highlighting the benefits, advantages and drawbacks. As a conclusion, the proposed antenna demonstrates to be a good solution to meet the design constraints for such an application: light, low cost, small size factor.

Short-term space safety analysis of LEO constellations and clusters

The large satellite constellations currently planned and deployed in Low Earth Orbit (LEO) bear some similarities with the clusters of derelict objects abandoned in different altitude bands in LEO. Given these similarities, an analysis of the collision risk associated with these orbital systems is performed with different analytical and numerical techniques.Different tools developed at IFAC-CNR for short to long-term constellation impact analysis are applied to ascertain the immediate (i.e., 1–20 years) effects related to the constellation deployment and execution and to evaluate the risk associated to the accumulation of massive derelict objects in a restricted region of space (i.e., clusters). The intra-group collision probability caused by the repeated orbital crossing between the members of two selected constellations and of some of the clusters of objects in LEO are computed, cumulated over the time span of the analysis (20 years) and compared. While the collision probability obtained in the case of the constellation could be efficiently mitigated by proper management and operations (i.e., debris mitigation practices and collision avoidance), the high level of risk associated with the clusters of derelict uncontrolled objects cannot be avoided, unless pro-active actions are undertaken to remove the large targets from the space. From all the analysis performed, the cluster located around 975 km of altitude stands up as particularly dangerous population in the already critical LEO region.

Downlink Coverage and Rate Analysis of Low Earth Orbit Satellite Constellations Using Stochastic Geometry

As low Earth orbit (LEO) satellite communication systems are gaining increasing popularity, new theoretical methodologies are required to investigate such networks' performance at large. This is because deterministic and location-based models that have previously been applied to analyze satellite systems are typically restricted to support simulations only. In this paper, we derive analytical expressions for the downlink coverage probability and average data rate of generic LEO networks, regardless of the actual satellites' locality and their service area geometry. Our solution stems from stochastic geometry, which abstracts the generic networks into uniform binomial point processes. Applying the proposed model, we then study the performance of the networks as a function of key constellation design parameters. Finally, to fit the theoretical modeling more precisely to real deterministic constellations, we introduce the effective number of satellites as a parameter to compensate for the practical uneven distribution of satellites on different latitudes. In addition to deriving exact network performance metrics, the study reveals several guidelines for selecting the design parameters for future massive LEO constellations, e.g., the number of frequency channels and altitude.

Accuracy criterion and analysis of continuous earth observation constellations

A criterion for analyzing the accuracy characteristics of applied satellite constellations (ASC) possible structures for observing targets in the Earth surface and/or near-surface layer is proposed. The criterion is not related to features of onboard hardware and depends on structure, parameters and dynamics of ASC. The criterion is based on consideration of determination accuracy of the objects geographical coordinates. An algorithm for numerical simulation of ASC is presented. Comparative accuracy estimates for various types of ASC are presented. Accuracy characteristics of Walker constellations and Near-Polar Satellite Constellations with various pattern types are considered. The main design-ballistic parameters that determine the accuracy of ASC and affect the cost of their creation are determined, and the nature of these parameters influence also shown. Results can be used for initial decision of ASC pattern during preliminary design stage. Key words: observing satellite constellations, accuracy criterion, analysis of observation constellations, Walker constellations, Near-Polar Satellite Constellations.

A multi-method approach to explore environmental governance: a case study of a large, densely populated dry forest region of the neotropics

Semiarid regions are often secondary on the national to global (scientific) agenda, especially if abundant vegetation elsewhere draws attention and the local population is considered backwards thinking and poverty-stricken. The Caatinga, our case study, is such a region, home to millions of Brazilians and a vast biodiversity. Unfortunately, a widely uncoordinated land use change and biodiversity decline are happening, while farmers’ livelihoods are at risk. We hypothesize substantial weaknesses in the current governance practices. To explore governance of the less noticed region, we conducted interviews and field visits and complemented the findings with the literature and internet resources. Our multi-method approach combines the social–ecological systems framework with constellation analysis and dynamic modeling. The aim was to understand the current state of governance in the region and identify clues for more sustainable land management. The use and conservation of Caatinga are negotiated at multiple levels, which are only sporadically interlinked. The conversion of forest land into alternative land uses shifts and shares responsibility among different sectors, while cross-sectoral cooperation is rarely observed. The region and its population face massive prejudices. Obstructing attitudes, such as thinking in dichotomies, and paternalistic and opportunistic approaches, are being addressed by some new coalitions taking alternative action. It is unlikely that these isolated initiatives will converge by themselves to a larger transformation toward sustainable resource use. There is a need to bring the dispersed actions in a more focused and coordinated approach, integrating socioeconomic and ecological concerns, values, and partnerships.

An integrative approach to the facile functional classification of dorsal root ganglion neuronal subclasses

Somatosensory neurons have historically been classified by a variety of approaches, including structural, anatomical, and genetic markers; electrophysiological properties; pharmacological sensitivities; and more recently, transcriptional profile differentiation. These methodologies, used separately, have yielded inconsistent classification schemes. Here, we describe phenotypic differences in response to pharmacological agents as measured by changes in cytosolic calcium concentration for the rapid classification of neurons in vitro; further analysis with genetic markers, whole-cell recordings, and single-cell transcriptomics validated these findings in a functional context. Using this general approach, which we refer to as tripartite constellation analysis (TCA), we focused on large-diameter dorsal-root ganglion (L-DRG) neurons with myelinated axons. Divergent responses to the K-channel antagonist, κM-conopeptide RIIIJ (RIIIJ), reliably identified six discrete functional cell classes. In two neuronal subclasses (L1 and L2), block with RIIIJ led to an increase in [Ca] i Simultaneous electrophysiology and calcium imaging showed that the RIIIJ-elicited increase in [Ca] i corresponded to different patterns of action potentials (APs), a train of APs in L1 neurons, and sporadic firing in L2 neurons. Genetically labeled mice established that L1 neurons are proprioceptors. The single-cell transcriptomes of L1 and L2 neurons showed that L2 neurons are Aδ-low-threshold mechanoreceptors. RIIIJ effects were replicated by application of the Kv1.1 selective antagonist, Dendrotoxin-K, in several L-DRG subclasses (L1, L2, L3, and L5), suggesting the presence of functional Kv1.1/Kv1.2 heteromeric channels. Using this approach on other neuronal subclasses should ultimately accelerate the comprehensive classification and characterization of individual somatosensory neuronal subclasses within a mixed population.

Water as a Weapon of War in the Tigris-Euphrates Basin

The paper aims to present water as a weapon of war in the Tigris-Euphrates Basin, as well as the role and significance of water for a new architecture of global security. The main goal of the study is to find an answer to the research question of whether water the Tigris-Euphrates Basin will be still a tool for fighting or cooperation as an effective tool for facing strategic challenges. The research hypothesis is that the issue of challenges related to water in the Euphrates River basin will, first of all, follow the social and political-economic relations between Turkey, Iraq and Syria and external factors. The research was conducted using a descriptive-analytical method. Moreover, this research is based on the neorealist theory of international relations, and the concept of international constellation analysis, as well as the theory of neo-institutionalism. Future anarchical global security architecture will lead to a hegemonic system of water relations. Therefore, without international coordination and far-reaching strategy in the face of the emerging anarchic global security structure, stable water cooperation in this region cannot be reached.

Bridging Theories and Practices: Boundary Objects and Constellation Analysis as Vehicles for Interdisciplinary Knowledge Integration

Knowledge integration is a major challenge of interdisciplinary research. Substantially different stocks of knowledge based on different scientific backgrounds, uses of language, methodologies, and epistemologies must be integrated into the research process. Addressing this challenge, this paper exemplifies the process of interdisciplinary knowledge integration drawing on the example of the junior research group DynaMo—Mobility-Energy Dynamics in Urban Areas that deals with the sustainable transformation of urban mobility systems. This paper shows how we apply the boundary object concept in combination with the method of Constellation Analysis as vehicles for interdisciplinary knowledge integration. By innovatively combining the boundary object concept with Constellation Analysis we a) suggest a self-reflective tool for structuring the process of knowledge integration and b) further operationalize the boundary object with the help of core concepts. The approach is illustrated with the boundary object sustainable transformation of urban passenger mobility used by DynaMo. In doing so, the paper aims to add an instrument to the toolkit of inter- and transdisciplinary research and offers practical knowledge for its application.

Good Governance: A Framework for Implementing Sustainable Land Management, Applied to an Agricultural Case in Northeast-Brazil

Land management needs to cope with persistent environmental and societal changes. This requires functional governance systems. The purpose of this research is to develop a good governance framework for the implementation of sustainable land management. Good governance theory is extensive, although its operationalization remains difficult. We derived a set of good governance attributes from the literature: (i) the functionality of the regulatory framework, (ii) the legitimacy and accountability of the actors, (iii) the fairness and transparency of the decision-making processes, and (iv) quality control and adaptiveness. These constitute a framework which, supported by guiding questions, facilitates the evaluation of governance attributes to assess sustainable land management practices. We applied the scheme to a case study in Northeast Brazil regarding sustainable land management where biological pest control is considered to be a biodiversity-related ecosystem service. Since its adoption often falls short of expectations, we scrutinized its governance system. First, experts answered our guiding questions, and second, we involved local stakeholders in the discussion of good governance attributes through the participatory approach of constellation analysis. Trust in agricultural consultants and issues of the practical application of pest control turned out to be crucial. The workshop participants requested a model farm to build more trust and experience. There was considerable demand for policy at the national planning level to formulate and monitor the content of the agricultural advisory program. Our conceptualized framework of good governance questions provides systematization for planning and steering the implementation of sustainable land management practices.