DISTRIBUTIONS OF AIR TRAFFIC CONTROL STUDENTS’ ATTITUDES TOWARDS WORKLOAD

Mental workload is a well-known concept with a long development history. It can be used to examine students’ attitudes at the end of the educational process and compare them in groups or separately. However, building a continuous workload profile across the range of task complexity increase is still an urgent issue. All four groups of methods used to define mental workload have such flaws for the workload profile construction process as significant time requirements, single value processing and post-processing of the received results. Only one of them can be used without modifications to construct the operator’s attitude chart (profile) regarding the workload range and it doesn’t operate with more reliable absolute values. To resolve this problem, a special workload assessment grid was developed, considering the advantages of a subjective group of methods and seven core characteristics. The reasoning for grid axes choice, threshold values, and question formulation were provided. Statistics were calculated for the full sample, different grades, and educational institutions. Comparison of the received responses with referential values, cross-comparison between institutions and different grades were performed. The results contribute to such important aspects of workload, as redlines, workload profiling, and operator’s comparison.

The Effects of Absorbing Materials on the Homogeneity of Composite Heating by Microwave Radiation

When cured in a microwave, flat thin composite panels can experience even heat distribution throughout the laminate. However, as load and geometric complexity increase, the electromagnetic field and resulting heat distribution is altered, making it difficult to cure the composite homogeneously. Materials that absorb and/or reflect incident electromagnetic radiation have the potential to influence how the field behaves, and therefore to tailor and improve the uniformity of heat distribution. In this study, an absorber was applied to a composite with non-uniform geometry to increase heating in the location which had previously been the coldest position, transforming it into the hottest. Although this result overshot the desired outcome of temperature uniformity, it shows the potential of absorbing materials to radically change the temperature distribution, demonstrating that with better regulation of the absorbing effect, a uniform temperature distribution is possible even in non-uniform composite geometries.

Multiple evolutionary origins and losses of tooth complexity in squamates

Teeth act as tools for acquiring and processing food, thus holding a prominent role in vertebrate evolution. In mammals, dental-dietary adaptations rely on tooth complexity variations controlled by cusp number and pattern. Complexity increase through cusp addition has dominated the diversification of mammals. However, studies of Mammalia alone cannot reveal patterns of tooth complexity conserved throughout vertebrate evolution. Here, we use morphometric and phylogenetic comparative methods across fossil and extant squamates to show they also repeatedly evolved increasingly complex teeth, but with more flexibility than mammals. Since the Late Jurassic, multiple-cusped teeth evolved over 20 times independently from a single-cusped common ancestor. Squamates frequently lost cusps and evolved varied multiple-cusped morphologies at heterogeneous rates. Tooth complexity evolved in correlation with changes in plant consumption, resulting in several major increases in speciation. Complex teeth played a critical role in vertebrate evolution outside Mammalia, with squamates exemplifying a more labile system of dental-dietary evolution.

Splitting Choice and Computational Complexity Analysis of Decision Trees

Some theories are explored in this research about decision trees which give theoretical support to the applications based on decision trees. The first is that there are many splitting criteria to choose in the tree growing process. The splitting bias that influences the criterion chosen due to missing values and variables with many possible values has been studied. Results show that the Gini index is superior to entropy information as it has less bias regarding influences. The second is that noise variables with more missing values have a better chance to be chosen while informative variables do not. The third is that when there are many noise variables involved in the tree building process, it influences the corresponding computational complexity. Results show that the computational complexity increase is linear to the number of noise variables. So methods that decompose more information from the original data but increase the variable dimension can also be considered in real applications.

Nutshells as Efficient Biosorbents to Remove Cadmium, Lead, and Mercury from Contaminated Solutions

The release of potentially toxic elements into the environment, and their effects on aquatic ecosystems still present a real threat. To avoid such contamination, the use of biological sorbents as an alternative to conventional and expensive water remediation techniques has been proposed. The present study evaluated the potential of 0.5 g L−1 of peanut, hazelnut, pistachio, walnut, and almond shells to remove the requisite concentrations of cadmium (Cd), lead (Pb), and mercury (Hg) from contaminated water. Hazelnut shells were identified as the sorbent with the highest potential and were evaluated in mono- and multi-contaminated mineral water. The influence of sorbent-intrinsic and solution-intrinsic characteristics were assessed. Differences among sorbents were attributed to varying percentages of their main components: cellulose, hemicellulose, and lignin. Matrix complexity increase caused a decrease in Cd removal, presumably due to the diminution in electrostatic interaction, and complexation with anions such as Cl−. When simultaneously present in the solution, contaminants competed, with Pb showing higher affinity to the sorbent than Hg. High efficiencies (>90%) obtained for hazelnut shells for all elements in ultrapure water and for Pb and Hg in mineral water) reveals the high potential of this low-cost and abundant waste for use in the remediation of contaminated waters (circular economy).

Hierarchical Distribution Matching for Probabilistic Amplitude Shaping

Probabilistic amplitude shaping—implemented through a distribution matcher (DM)—is an effective approach to enhance the performance and the flexibility of bandwidth-efficient coded modulations. Different DM structures have been proposed in the literature. Typically, both their performance and their complexity increase with the block length. In this work, we present a hierarchical DM (Hi-DM) approach based on the combination of several DMs of different possible types, which provides the good performance of long DMs with the low complexity of several short DMs. The DMs are organized in layers. Each upper-layer DM encodes information on a sequence of lower-layer DMs, which are used as “virtual symbols”. First, we describe the Hi-DM structure, its properties, and the encoding and decoding procedures. Then, we present three particular Hi-DM configurations, providing some practical design guidelines, and investigating their performance in terms of rate loss and energy loss. Finally, we compare the system performance obtained with the proposed Hi-DM structures and with their single-layer counterparts: a 0.19dB SNR gain is obtained by a two-layer Hi-DM based on constant composition DMs (CCDM) compared to a single-layer CCDM with same complexity; a 0.12dB gain and a significant complexity reduction are obtained by a Hi-DM based on minimum-energy lookup tables compared to a single-layer DM based on enumerative sphere shaping with same memory requirements.

Multiple evolutionary origins and losses of tooth complexity in squamates

Teeth act as tools for acquiring and processing food and so hold a prominent role in vertebrate evolution1,2. In mammals, dental-dietary adaptations rely on tooth shape and complexity variations controlled by cusp number and pattern – the main features of the tooth surface3,4. Complexity increase through cusp addition has dominated the diversification of many mammal groups3,5-9. However, studies of Mammalia alone don’t allow identification of patterns of tooth complexity conserved throughout vertebrate evolution. Here, we use morphometric and phylogenetic comparative methods across fossil and extant squamates (“lizards” and snakes) to show they also repeatedly evolved increasingly complex teeth, but with more flexibility than mammals. Since the Late Jurassic, six major squamate groups independently evolved multiple-cusped teeth from a single-cusped common ancestor. Unlike mammals10,11, reversals to lower cusp numbers were frequent in squamates, with varied multiple-cusped morphologies in several groups resulting in heterogenous evolutionary rates. Squamate tooth complexity evolved in correlation with dietary change – increased plant consumption typically followed tooth complexity increases, and the major increases in speciation rate in squamate evolutionary history are associated with such changes. The evolution of complex teeth played a critical role in vertebrate evolution outside Mammalia, with squamates exemplifying a more labile system of dental- dietary evolution.

Providing Clarity on Big Data Technologies

Big Data is a term that gained popularity due to its potential benefits in various fields, and is progressively being used. However, there are still many gaps and challenges to overcome, especially when it comes to the selection and handling of relevant technologies. A consequence of the huge number of manifestations in this area, growing each year, the uncertainty and complexity increase. The lack of a classification approach causes a growing demand for more experts with a broad knowledge and expertise. Using various techniques of ontology engineering and following the design science methodology, this work proposes the Big Data Technology Ontology (BDTOnto) as a comprehensive and sustainable classification approach to classify big data technologies and their manifestations. In particular, a reusable, extensible and adaptable artifact in the form of an ontology will be developed and evaluated.

The Valences of Communication in a Crisis Situation

The frequency with which it is used - ubiquitously integrating with the linguistic arsenal of modern man - places next to the concept of crisis the meaning of those categories of events that bring with them deviations from the axis of a natural and desirable course of daily life. Such eventual frameworks (from natural disasters, economic recession, pandemic, to situations that upset to reconfigure family life, etc.), through their diversity and complexity, increase the difficulty of exhaustive theoretical classification of the concept. There are situations that take place against a background of accentuated emotional vulnerability, with behavioral changes not specific to ordinary life contexts, with exaggerated response reactions, the one in question being in a perpetual search for answers. As a tool that vigorously proves its potential in interpersonal relations in general, effective communication remains indispensable for the trajectory of the crisis situation, whatever its configuration. Integrating a perspective of interdisciplinary approach - anthropological, chronological (historical), psycho-socio-behavioral, and crisis management - the article highlights the interdependence of the concepts of crisis and communication, emphasizing the need for effective cooperation between the two, which becomes an imperative of the situation. crisis.

Efficient Hybrid Cryptography Algorithm

Cryptography is the operation of transferring a specific message to prevent an attacker from accessing the contents of a message. To increase the level of security in any communication, both parties must have a copy of the encryption key. The Data Encryption Standard algorithm is insufficient due to its weak key generation, so that the key must be reconfigured to make this algorithm more secure, effective, and stronger. The key for encryption enhances securities of the Data Encryption Standard algorithm. This research assumed a combination of two efficient encryption algorithms to achieve the goal of information security by adding a new level of security to the Data Encryption Standard algorithm using the elliptic curve cryptography algorithm. This aim was met by adding two new key functions; the first one is EncK(), and the second one is DecK() for an encryption and decryption key of the Data Encryption Standard algorithm to make this algorithm more secure against attackers. The results obtained from this research also demonstrate good resistance against a brute-force attack, which makes the system more effective by applying the elliptic curve cryptography algorithm to encrypt and decrypt keys using the Data Encryption Standard. In addition, these modifications enhance the degree of complexity, increase key search space, and make the ciphered message more difficult for an attacker to crack.