Map Symbols Research Articles

A note on the space of all Toeplitz operators

Abstract We study Toeplitz operators on the space of all real analytic functions on the real line and the space of all holomorphic functions on finitely connected domains in the complex plane. In both cases, we show that the space of all Toeplitz operators is isomorphic, when equipped with the topology of uniform convergence on bounded sets, with the symbol algebra. This is surprising in view of our previous results, since we showed that the symbol map is not continuous in this topology on the algebra generated by all Toeplitz operators. We also show that in the case of the Fréchet space of all holomorphic functions on a finitely connected domain in the complex plane, the commutator ideal is dense in the algebra generated by all Toeplitz operators in the topology of uniform convergence on bounded sets.

Spatial configuration of warehouses of different sizes in the City of Cape Town municipality

Background: Various metropolitan areas have become key centres for logistics activities, leading to a significant increase in the number of warehouses. However, there is a gap in the literature regarding the locational patterns of warehouses of different sizes in Africa.Objectives: To analyse the locational patterns of warehouses of different sizes within the City of Cape Town municipality, South Africa. The analysis focuses on the main factors influencing the placement of warehouses: transport infrastructure, land availability, proximity to customers and land-use zoning.Method: The study categorised warehouses based on their building footprint sizes, using the classifications of xx-small, x-small, small, medium, x-large and mega. A total of 396 warehouses were categorised accordingly. Proportional symbol mapping was then conducted in ArcGIS 10.1, assigning each warehouse type a specific weighting.Results: The study found that the areas surrounding the Port of Cape Town predominantly accommodated x-small warehouses. A diverse concentration of warehouses was identified along the railway, near the junctions of regional and national roads and within the areas enclosed by these roads. In addition, warehouses of diverse sizes were primarily situated in the main industrial zones of the municipality.Conclusion: The City of Cape Town municipality is encouraged to promote the consolidation of particularly large warehouses in strategic locations. These include industrial areas not geographically near the Port of Cape Town but with railway access to the port.Contribution: The study will contribute towards enhancing the sustainability and efficiency of logistics processes within the City of Cape Town.

Polarized APSK modulation system with polymorphic SC signals

AbstractThis paper discusses a new symbol modulation scheme known as polarized amplitude and phase shift keying, (‐APSK) modulation with four rings in its basic form. The new scheme maps power‐polarized symbol pairs on its constellation in order to increase the number of data symbols. ‐APSK exploits a symbol mapper based on a conjugate power splitting algorithm. Product modulation is applied, where a voltage signal of a specified amplitude and phase is multiplied by another current signal of a specified amplitude and phase, thus forming polymorphic signals in the product constellation. At the receiver, an isolated detection is performed, where the voltage signal is detected independently of the received current signal. A selection combining scheme is then used. The results depict unity peak‐to‐average power ratio and low average symbol energy, which is desirable for Green communications in 5G networks. It presents lower bit error rates when compared with the state‐of‐the art ‐ary quadrature amplitude modulation, with a signal‐to‐noise ratio gap of at least . The proposed analytical framework closely matches the simulations for bit error rates under .

An additive variant of the differential symbol maps

An additive variant of the differential symbol maps

Visualization of explainable artificial intelligence for GeoAI

Shapley additive explanations are a widely used technique for explaining machine learning models. They can be applied to basically any type of model and provide both global and local explanations. While there are different plots available to visualize Shapley values, there is a lack of suitable visualization for geospatial use cases, resulting in the loss of the geospatial context in traditional plots. This study presents a concept for visualizing Shapley values in geospatial use cases and demonstrate its feasibility through an exemplary use case—predicting bike activity in a rental bike system. The visualizations show that visualizing Shapley values on geographic maps can provide valuable insights that are not visible in traditional plots for Shapley additive explanations. Geovisualizations are recommended for explaining machine learning models in geospatial applications or for extracting knowledge about real-world applications. Suitable visualizations for the considered use case are a proportional symbol map and a mapping of computed Voronoi values to the street network.

Evaluation of Multi-Valued Data Transmission in Two-Dimensional Symbol Mapping using Linear Mixture Model

Evaluation of Multi-Valued Data Transmission in Two-Dimensional Symbol Mapping using Linear Mixture Model

A step in a new direction: NVIDIA GPU kernel driver memory forensics

In the ever-expanding landscape of computation, graphics processing units have become one of the most essential types of devices for personal and commercial needs. Nearly all modern computers have one or more dedicated GPUs due to advancements in artificial intelligence, high-performance computing, 3D graphics rendering, and the growing demand for enhanced gaming experiences. As the GPU industry continues to grow, forensic investigations will need to incorporate these devices, given that they have large amounts of VRAM, computing power, and are used to process highly sensitive data. Past research has also shown that malware can hide its payloads within these devices and out of the view of traditional memory forensics. While memory forensics research aims to address the critical threat of memory-only malware, no current work focuses on video memory malware and the malicious use of the GPU. Our work investigates the largest GPU manufacturer, NVIDIA, by examining the newly released open-source GPU kernel modules for the development of forensic tool creation. We extend our impact by creating symbol mappings between open and closed-source NVIDIA software that enables researchers to develop tools for both “flavors” of software. We specifically focus our research on artifacts found in RAM, providing the foundational methods to detect and map NVIDIA Object Compiler Structures for forensic investigations. As a part of our analysis and evaluation, we examined the similarities between open-and-closed kernel modules by collecting structure sizes and class IDs to understand the similarities and differences. A standalone tool, NVSYMMAP, and Volatility plugins were created with this foundation to automate this process and provide forensic investigators with knowledge involving processes that utilized the GPU.

Research on the Movement Speed of Situational Map Symbols Based on User Dynamic Preference Perception

When designing situational maps, selecting distinct and visually comfortable movement speeds for dynamic elements is an ongoing challenge for designers. This study addresses this issue by conducting two experiments to measure the human eye’s ability to discern moving speeds on a screen and examines how symbol movement speeds within situational maps affect users’ subjective experiences, task performance, and visual comfort. The first experiment measured participants’ speed discrimination capabilities for Landolt Ring of varying sizes moving at 0–256°/s, yielding speed discrimination thresholds of 7–23% and a sensitive velocity range of 1–64°/s. The second experiment evaluated observers’ visual perceptions of moving elements within a cognitive task across the same range of 1–64°/s, identifying three significant benchmarks—8°/s, 16°/s, and 32°/s. These can be utilized to categorize slow-, moderate-, and fast-moving symbols in situational maps. The findings can aid in designing human–machine interface environments with improved viewer experience and visual comfort for both Air Traffic Control interfaces and situational maps.

Investigating the Readability of School Geographic Map Symbols Using Eye-Tracking Technology

Geography atlas is an educational material that is very important in geography education. For the eye tracking experiment, six mineral maps were selected from different geography atlases for high school students. The aim of this study was to analyze which design of conventional symbols is more understandable for high school students. We hope that the presented methodology and the case study will help mapmakers to create more effective school geographic maps.

A Segmented Sliding Window Reference Signal Reconstruction Method Based on Fuzzy C-Means

Reference signal reconstruction serves as a crucial technique for suppressing multipath interference and noise in the reference channel of passive radar. Aiming at the challenge of detecting Low-Slow-Small (LSS) targets using Digital Terrestrial Multimedia Broadcasting (DTMB) signals, this article proposes a novel segmented sliding window reference signal reconstruction method based on Fuzzy C-Means (FCM). By partitioning the reference signals based on the structure of DTMB signal frames, this approach compensates for frequency offset and sample rate deviation individually for each segment. Additionally, FCM clustering is utilized for symbol mapping reconstruction. Both simulation and experimental results show that the proposed method significantly suppresses constellation diagram divergence and phase rotation, increases the adaptive cancellation gain and signal-to-noise ratio (SNR), and in the meantime reduces the computation cost.

Frequency Offset Estimation for UWB-OFDM System using Weight and Exhaustiveness based Monarch Butterfly Optimization Approach

The performance of an OFDM system has limitation because the carrier frequency offset (CFO) and sampling frequency offset (SFO) is not estimated correctly. Current methods propose the way of obtaining frequency estimation by using the evolutionary algorithm, but the evolution algorithm suffers from the premature convergence problem. In order to provide efficient frequency offset estimation, this paper proposed weight and exhaustiveness based monarch butterfly optimization approach. First, on the transmitter block, for modulating an input symbol, the Hybrid-Quadrature Phase-Shift Keying modulation scheme is used. Brunn’s IFFT is done at each transmitter for symbol mapping and then in each transmitter block cyclic prefix is inserted. After that, WE-MBO algorithm estimates the frequency offset. On receiver side, the inverse operation of the transmitter is performed. After comparison of proposed system with the existing system, the proposed system gave better performance.

The significance of the cartographic sign: influences of symbol shape on intuitive judgments

ABSTRACT Some of the maps we encounter in our daily lives have become simpler and smaller, to the extent that they may employ only a single symbol to depict a particular incident. As maps and their symbols are never neutral, research on visual semiotics emphasizes the importance of exploring the implicit, connotative effects of signs on human responses. This study, therefore, aimed to assess the influence of simple monothematic web maps on map users’ judgments. It examined how the severity of negative geospatial events was perceived when represented by cartographic point symbols that varied in shape. In total, 72 maps (12 negative topics, each depicted by six map symbols) were rated by 82 participants. The results showed that asymmetric star symbols led to the highest estimates of the events’ perceived severity, followed by symmetric star symbols. Triangle and rhomb led to the lowest ratings. Circle and square showed the most variable results: they led to high and low ratings depending on the map topic. The findings demonstrate that map symbols influence how people imagine geospatial events. These findings call for a more vigorous focus on the connotative meanings of visual signs in cartographic research and practice.

Fixation-related potentials during mobile map assisted navigation in the real world: The effect of landmark visualization style.

An often-proposed enhancement for mobile maps to aid assisted navigation is the presentation of landmark information, yet understanding of the manner in which they should be displayed is limited. In this study, we investigated whether the visualization of landmarks as 3D map symbols with either an abstract or realistic style influenced the subsequent processing of those landmarks during route navigation. We utilized a real-world mobile electroencephalography approach to this question by combining several tools developed to overcome the challenges typically encountered in real-world neuroscience research. We coregistered eye-movement and EEG recordings from 45 participants as they navigated through a real-world environment using a mobile map. Analyses of fixation event-related potentials revealed that the amplitude of the parietal P200 component was enhanced when participants fixated landmarks in the real world that were visualized on the mobile map in a realistic style, and that frontal P200 latencies were prolonged for landmarks depicted in either a realistic or abstract style compared with features of the environment that were not presented on the map, but only for the male participants. In contrast, we did not observe any significant effects of landmark visualization style on visual P1-N1 peaks or the parietal late positive component. Overall, the findings indicate that the cognitive matching process between landmarks seen in the environment and those previously seen on a map is facilitated by more realistic map display, while low-level perceptual processing of landmarks and recall of associated information are unaffected by map visualization style.

Symbol of Communication between Worship Leader and Music Priest in Maintaining Harmonization of Worship Music at GBI Lembang Bandung

Music has an important role in Christian worship. Harmonious music is solemnity if the Worship leader and musician church can carry out their duties properly. Worship leader and musician communicate using symbols when leading worship. This research aims to determine how the meaning of the communication symbols of church music groups in maintaining the harmonization of worship music. This research uses qualitative method with a symbolic interaction study approach. Data was collected through observation, interviews and documentation. The informant determination technique used is purposive sampling.. The results of the study found 2 parts of the symbol. Namely song map and keytone. The song map symbol is a part of a song element that is used when the music is already running and is given when the musical verse is about to end, with the aim of bridging every movement of the musical verse. Keytone symbols are used to align the chords. The language used verbally and nonverbally. The key tone is used by worship leaders to music priests, and music priests to one another. The music priest has a dominant role according to the symbol of the song map. The keyboardist has a role on the cooling down section, guitarist on interlude, drums on full music and overtones. Worship leaders and music priests must have spiritual criteria as pulpit ministers, because spiritual criteria are the main key to be good to God.

How can children best learn map skills? a step-by-step approach

ABSTRACT This study contributes to our understanding of children's development of map-reading skills through a systematic ‘step-by-step approach’. Utilising an ecological research design, we investigated how children perceive and utilise maps in a large-scale outdoor environment. A total of 156 children, aged 5–11 (both boys and girls), participated in the study, tasked with locating ten controls in the terrain using five different types of maps. The study measured accuracy in wayfinding (the number of correctly identified controls) and efficiency in wayfinding (the time spent on the task). The results revealed that children exhibited better mastery of perspective maps compared to symbolic maps, with older children demonstrating significantly greater proficiency with symbolic maps than younger children. Notably, there were no significant differences in performance between boys and girls.

Haptic search asymmetry does not occur due to different-shaped tactile symbols on capsule paper.

Previous research on haptic search using sandpaper with different roughness levels as a target and distractors showed that rough sandpaper among fine "pops out" and can be searched for in a shorter time than when the roles of the target and distractors are reversed. However, it is not clear whether the same search asymmetry occurs with differences in the shapes of tactile symbols on capsule paper. To explore this possibility, we conducted a haptic search experiment using circles with or without a dot on capsule paper as a target and distractors, which are often used as point symbols in tactile maps for the blind. Contrary to our expectations, haptic search asymmetry did not occur between these two tactile symbols. Regardless of target type, the search times increased in proportion to the number of items (distractors plus target), as participants tended to adopt serial search strategy in which they placed their index or middle finger on the tactile symbol to distinguish it every time they found a new one. The ratio of the search times for target-absent to target-present trials is precise alignment with the occurrence rate of repetitive search trials.

TRNA: The operational RNA code and protein folding

tRNA: The operational RNA code and protein folding Charles W. Carter, Jr., from the Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, relates molecular recognition used in genetic coding to structures of aminoacyl-tRNA synthetases and their cognate tRNAs. Genetic coding is simultaneously widely understood and little appreciated. Widely understood because Marshall Nierenberg worked out the codon assignments within a decade or so of the double helical structure of DNA by Watson and Crick (1). Little appreciated because a code, as far as we know, is something Nature had never produced – a symbolic mapping of the physical chemistry of the 20 amino acid side chains. The Morse code is a widely appreciated example. Like inheritance, the genetic code is a property of biology.

$C^{\ast}$-algebraic approach to the principal symbol. III

We treat the notion of principal symbol mapping on a compact smooth manifold as a \ast -homomorphism of C^{\ast} -algebras. Principal symbol mapping is built from the ground, without referring to the pseudodifferential calculus on the manifold. Our concrete approach allows us to extend Connes trace theorem for compact Riemannian manifolds.

Discovering Promising Biomarkers and Therapeutic Targets for Duchenne Muscular Dystrophy: a Multiomics Meta-Analysis Approach.

Duchenne muscular dystrophy (DMD) is a genetic disorder that causes muscle weakness and degeneration. In this study, we identified potential biomarkers and drug targets for DMD through a comprehensive meta-analysis of mRNA profiles. We conducted an in-depth analysis of three microarray datasets from the GEO database, utilizing the Affymetrix platform. A rigorous data pre-processing pipeline encompassed background correction, normalization, log2 transformation and probe-to-gene symbol mapping. Robust multi-array average method followed by Limma package in R was employed to ensure differential expression analysis within individual datasets, yielding gene-specific p-values. We identified 63 genes exhibiting statistically significant differential expression across the three datasets (p < 0.05) and an absolute log fold change > 1.5. Functional enrichment analyses of these differentially expressed genes were done, followed by pathway analyses. Our results suggested pertinent biological processes, molecular functions and cellular components associated with DMD. Finally, eight hub genes-COL6A3, COL1A1, COL3A1, COL1A2, POSTN, TIMP1, THBS2 and SPP1-were pinpointed as central players in the network. Two differentially expressed genes with substantial absolute log-fold changes, namely, DMD, downregulated and MYH3, upregulated, were identified as potential therapeutic candidates. In light of these findings, our work contributes not only to understanding DMD at the molecular level but also presents potential targets for therapeutic strategies. Finally,our study facilitates the development of therapeuticinterventions that can effectively control and mitigate the impact of DMD.

Dual Toeplitz operators on the orthogonal complement of the harmonic Bergman space

&lt;p&gt;This paper aimed to give some partial answers to the zero-product problem and commutativity problem concerning dual Toeplitz operators with nonharmonic symbols on the orthogonal complement of the harmonic Bergman space. Using the symbol map, we described the necessary condition for $ S_{\varphi_1}S_{\varphi_2}\cdots S_{\varphi_N} = 0 $ with radial symbols. Furthermore, we established the sufficient and necessary conditions for $ S_{\varphi}S_{ \psi} = S_{\psi}S_{\varphi} $ with $ \varphi(z) = az^{p_1}\overline{z}^{q_1}+bz^{p_2}\overline{z}^{q_2} $ and $ \psi(z) = z^{s}\overline{z}^{t} $.&lt;/p&gt;