SATELLITE SELECTION ALGORITHMS FOR POSITIONING, NAVIGATION AND TIMING USERS

Проведен обзор методов и алгоритмов формирования рабочего созвездия навигационных космических аппаратов при решении задач определения местоположения потребителя ГНСС. Появление новых орбитальных группировок и развитие прошлых поколений глобальных навигационных спутниковых систем (ГНСС) способствует увеличению как количества навигационных аппаратов, так и навигационных радиосигналов, излучаемых каждым спутником, в связи с чем решение проблемы выбора навигационных аппаратов является важной составляющей навигационной задачи. Рассмотрены исследования, посвященные типовым алгоритмам формирования рабочего созвездия, а также современным алгоритмам, построенным с привлечением элементов теории машинного обучения. Представлена связь ошибок определения координат потребителя, погрешностей определения псевдодальностей и пространственного расположения навигационных аппаратов и потребителя. Среди рассмотренных алгоритмов выделены три направления исследований: 1) нацеленных на поиск оптимального рабочего созвездия, обеспечивающего минимальную оценку выбранного геометрического фактора снижения точности; 2) нацеленных на поиск квазиоптимальных рабочих созвездий с целью уменьшения вычислительной сложности алгоритма ввиду большого количества видимых спутников; 3) позволяющих одновременно работать в совмещенном режиме по нескольким ГНСС. Приводятся особенности реализаций алгоритмов, их преимущества и недостатки. В заключении приведены рекомендации по изменению подхода к оценке эффективности алгоритмов, а также делается вывод о необходимости учета как геометрического расположения космических аппаратов, так и погрешности определения псевдодальности при выборе космического аппарата в рабочее созвездие The article provides an overview of methods and algorithms for forming a satellite constellation as a part of the navigation problem for the positioning, navigation and timing service. The emergence of new orbital constellations and the development of past GNSS generations increase both the number of navigation satellites and radio signals emitted by every satellite, and therefore the proper solution of satellite selection problem is an important component of the positioning, navigation and timing service. We considered the works devoted to typical algorithms of working constellation formation, as well as to modern algorithms built with the use of machine-learning theory elements. We present the relationship between user coordinates errors, pseudorange errors and the influence of spatial location of satellites and the user. Three directions of researche among reviewed algorithms are outlined: 1) finding the best satellite constellation that provides the minimum geometric dilution of precision; 2) finding quasi-optimal satellite constellation in order to reduce the computational complexity of the algorithm due to the large number of visible satellites; 3) possibility to work in a combined mode using radio signals of multiple GNSS simultaneously. The article presents the features of the algorithms' implementations, their advantages and disadvantages. The conclusion presents the recommendations to change the approach to assessing the performance of the algorithms, and concludes that it is necessary to take into account both the satellite geometric configuration, and pseudorange errors when satellite constellation is being formed

Essentials, Challenges, and Future Directions of Agricultural IoT

Agriculture plays a major role in the socio-economic structure of India. A recent report claimed that population of India is increasing faster than its capability to produce rice, wheat, and vegetables. The challenges in the area of agriculture are farming, watering, weather forecasting, marketing, and transportation. These challenges are to be addressed towards proper solution. If the infrastructure and productivity of the food increases, then India can easily feed its population as well as improve the exports of wheat and rice around the world. Internet of things (IoT) is an emerging technical area of agriculture domain. The advantage of IoT is to implement a smart agriculture management system with the help of analyzing the weather conditions of the field in order to optimize the usage of water, energy, fertilizers so as to maximize the crop yield. The objective of this study is to explore the possible contributions of IoT in Indian agriculture towards the improvements in irrigation infrastructure, agricultural productivity, food security, and rural job opportunities.

Circular economy – a new concept or a necessity

This article presents the idea of a circular economy (CE) as a practical implementation of postulates of the sustainable development of the economy. The focus is on the current situation of the use of natural resources and their capacity to meet global needs. The article has a theoretical character, enriched by presenting up-to-date statistical data concerning the use of natural resources. The main thesis of the article assumes that the CE model appears to be a proper solution for achieving sustainable development aims as it links environmental aspects with economic challenges. The aim of this article is to show the relationship between the increasing usage of natural resources and the need to save them through implementation of this complex solution. The results of the preliminary analysis indicate that the use of natural resources, corresponding to the level of global consumption, is still increasing and could threaten the possibility of meeting the needs of future generations.

Rethinking Basic Assumptions for Modeling Parasitic Capacitance in Inductors

<b>This paper rethinks the basic assumptions often used in analytically modeling parasitic capacitance in inductors. These assumptions are classified in two commonly-used physics-based analysis methods: the lumped capacitor network method and the energy conservation method. The lumped-capacitor network method is not the proper solution for calculating the equivalent parasitic capacitance in inductors at the first resonant frequency, but rather represents the equivalent parasitic capacitance above the last resonant frequency. The energy-conservation based method is shown to be more accurate and a reasonable solution to model the equivalent parasitic capacitance at the first resonant frequency. Multiple case studies of inductors are used for verifying the theory. </b>

Rethinking Basic Assumptions for Modeling Parasitic Capacitance in Inductors

<b>This paper rethinks the basic assumptions often used in analytically modeling parasitic capacitance in inductors. These assumptions are classified in two commonly-used physics-based analysis methods: the lumped capacitor network method and the energy conservation method. The lumped-capacitor network method is not the proper solution for calculating the equivalent parasitic capacitance in inductors at the first resonant frequency, but rather represents the equivalent parasitic capacitance above the last resonant frequency. The energy-conservation based method is shown to be more accurate and a reasonable solution to model the equivalent parasitic capacitance at the first resonant frequency. Multiple case studies of inductors are used for verifying the theory. </b>

Patriarchy and Inequality in Bharti Kirchner’s Sharmila’s Book and Pastries: A Novel of Desserts and Discoveries

Literature produced by men was a prejudiced one and focused mainly on the might of men and feebleness of female members. This was resisted by women writers and they started shattering the prejudiced views of men and gave a proper solution to it. Moreover, they violated the sanctities of women as mere service renders and broke the stereotyped images of women as the classical Sita or Kannagi who were projected as submissive partners having no identity of their own. It is only through the writings of women writers, the real identity of the women was recognized and they became equal partners at home and in the society. This awakening was highly instrumental in turning the dark pages of the history of literature and spread brightness and happiness everywhere. At present, gender inequality has gained global attraction and this has resulted in the production of vast literature.

Phishing Webpage Classification via Deep Learning-Based Algorithms: An Empirical Study

Phishing detection with high-performance accuracy and low computational complexity has always been a topic of great interest. New technologies have been developed to improve the phishing detection rate and reduce computational constraints in recent years. However, one solution is insufficient to address all problems caused by attackers in cyberspace. Therefore, the primary objective of this paper is to analyze the performance of various deep learning algorithms in detecting phishing activities. This analysis will help organizations or individuals select and adopt the proper solution according to their technological needs and specific applications’ requirements to fight against phishing attacks. In this regard, an empirical study was conducted using four different deep learning algorithms, including deep neural network (DNN), convolutional neural network (CNN), Long Short-Term Memory (LSTM), and gated recurrent unit (GRU). To analyze the behaviors of these deep learning architectures, extensive experiments were carried out to examine the impact of parameter tuning on the performance accuracy of the deep learning models. In addition, various performance metrics were measured to evaluate the effectiveness and feasibility of DL models in detecting phishing activities. The results obtained from the experiments showed that no single DL algorithm achieved the best measures across all performance metrics. The empirical findings from this paper also manifest several issues and suggest future research directions related to deep learning in the phishing detection domain.

Entrapment of Phenylalanine Ammonia-Lyase in Nanofibrous Polylactic Acid Matrices by Emulsion Electrospinning

Immobilization of the recombinant, plant-derived Petroselinum crispum phenylalanine ammonia lyase (PcPAL) in electrospun matrices have the potential to create promising, easy-to-use biocatalysts. Polylactic acid (PLA) a biologically inert, commercial biopolymer, was chosen as the material of the carrier system. PLA could be electrospun properly only from water-immiscible organic solvents, which limits its application as a carrier of sensitive biological objects. The emulsion electrospinning is a proper solution to overcome this issue using non-ionic emulsifiers with different hydrophilic-lipophilic balance (HLB) values. The stabilized emulsion could protect the sensitive PcPAL dissolved in the aqueous buffer phase and improve fiber formation, plus help to keep the biocatalytic activity of enzymes. In this study, the first approach is described to produce PLA nanofibers containing PcPAL enzymes by emulsion electrospinning and to use the resulted biocatalyst in the ammonia elimination reaction from l-phenylalanine.

FROM EXCAVATION DATA TO HBIM ENVIRONMENT AND CLOUD SHARING: THE CASE STUDY OF <i>DOMUS REGIA, SACRARIA MARTIS ET OPIS</i> (ROMAN FORUM, ROME - ITALY)

The importance of the Digital Atlas of Rome has been crucial in order to map and analyse archaeological remains of the monumental layout of ancient Rome, enhancing the contextual connections and easing the interpretation the original city-scapes and architecture. Then, the main goal has been twofold: to recompose the archaeological framework of available knowledge and to propose reconstructive hypotheses of ancient buildings. The Domus Regia, Sacraria Martis et Opis is one of these important buildings, excavated and documented over the years. In this regard, the archaeological data and the hypothetical reconstruction of the Domus Regia have been the focus of this project. In fact, the beginning of this integrative project is due to the desire to investigate how different methodology and workflows can be combined synergistically in a HBIM platform in order to ease data documentation, management and dissemination. Informative platforms and cloud solutions may be the proper solution for integrating metric data with semantic archaeological data, including and updating previous analyses. For this reason, the Domus Regia data has been managed inside a FOSS HBIM platform (FreeCAD), which was designed as a dynamic environment for modelling parametrically the ancient building and connecting related IFC objects with semantic information. Then, the resulted HBIM model has been valued and shared by using BIMData cloud platform and tested inside another environment developed ad-hoc for archaeological purposes.

Combating the constitutional crisis in Poland – Can the European Union provide an effective remedy?

Recent constitutional reforms in Poland have demonstrated a lack of respect for the rule of law and for the fundamental values which form the foundations of the EU legal order. The Polish authorities have substantially deviated from principles that the country has accepted as a part of the Copenhagen criteria. The aim of the article is to analyse the mechanisms and procedures applied by the EU institutions to address the systemic threats to the rule of law in Poland. The main focus of the assessment is on the effectiveness of the measure and its potential for a proper solution to the problem. The response provided by the EU demonstrate that there has been a shift from a political to judicial enforcement of values. The article argues that the remedies that were deemed to be the least suitable to address the systemic deficiencies in the rule of law – an infringement action and a preliminary ruling procedure – proved to be the most effective remedy to defend independence of the Polish judiciary. Unexpectedly, the most efficient institution to ensure the respect for values enshrined in Article 2 TEU in Poland proved to be the CJEU, providing extensive interpretation of Article 19 (1) TEU and Article 47 of the Charter. Nevertheless the values are still much more difficult to enforce than the law. While the most serious infringements have been reversed, this has not prevented the Polish authorities from further violating the rule of law.