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The purchasing behavior of the individual is a complex one and includes several aspects. Buying from physical stores and buying online are two options to make the purchase in all countries; one older, one newer. Obviously, online shopping is related to the advent of the Internet.There are differences between online buying behavior and buying behavior in physical stores. Buying from online stores means quite a few different details than buying from physical stores.There are also common points between the two types of buying behavior. There is sometimes also the middle way (i.e. to combine online purchases with those in physical stores), with several possible forms. One of these is searching for information online by shoppers, followed by buying from the physical store. Before the global coronavirus pandemic (Covid-19), with its peak in the period 2020-2022, most shoppers around the Globe did not shop online. The global Coronavirus pandemic has increased the number of those who have resorted to online shopping, out of necessity. After the global Coronavirus pandemic, the trend is to return to buying mainly from physical stores. It remains to be seen what the future will hold for us, in terms of the relationship between the two purchase options, which have both advantages and disadvantages. It is not very easy to predict what will be, related to the two buying behaviors.

Abstract Sporadic E (Es) layers are plasma irregularities significantly affecting radio communication and navigation systems. And, their dominant formation mechanism at mid‐latitudes, known as the wind shear theory, suggests that they serve as indicators of the atmosphere‐ionosphere coupling processes in the mesosphere and lower thermosphere region. On 15 January 2022, the Hunga Tonga‐Hunga Ha'api submarine volcanic eruption provided a unique opportunity to investigate the Es layer responses to lower atmospheric perturbations. Using the FORMOSAT‐7/COSMIC‐2 radio occultation and ground‐based ionosonde observations, this study reveals the spatial‐temporal behaviors of the Es layers after the Hunga volcanic eruption. The results show that significant Es layer perturbations occurred over the northwest of the epicenter ∼4 hr after the eruption and lasted for approximately ∼22 hr. We also calculated the geographical distribution of the vertical ion convergence (VIC) using neutral winds obtained from the Michelson Interferometer for Global High‐resolution Thermospheric Imaging on the Ionospheric Connection Explorer (ICON) satellite. A comparison of the geographical distribution of positive VIC and Es layer perturbations shows a good agreement, which indicates that the enhanced Es layers are caused by strong VIC associated with the atmospheric perturbations due to the eruption. This study presents observational evidence for coupling between the Es layer and lower atmospheric perturbations, which can be helpful for understanding the occasionality and variability of Es layer occurrence.

Using two separate databases of in situ ionospheric observations, we present case studies and perform a statistical investigation of the link between energetic precipitating particles during the polar night and high-latitude F-region steepening density spectra. Our study covers approximately 3 years of data obtained near the peak of the 24th solar cycle from four Defense Meteorological Satellite Program satellites and from the European Space Agency’s Swarm satellites. Focusing on the midnight sector of the auroral oval, we found that there is a near-perfect co-location between high-energy precipitating particles and occurrence of dissipating F-region plasma density spectra. This is because the precipitating energy flux strongly enhances the E-region Pedersen conductivity, allowing fast and efficient dissipation of kilometer-scale F-region irregularities. Spectra that are possibly non-dissipating are in turn co-located with the distribution of soft electron precipitation. Together, dissipating and non-dissipating density spectra constitute two distinct irregularity regimes. Surprisingly, we also found that efficient dissipation notwithstanding, high-energy precipitating particles cause a net increase in the F-region irregularity power, suggesting that growth and dissipation are interlinked and that some of the observed F-region irregularities may conceivably be generated in the E region. This work is expected to be beneficial for the classification of F-region in situ density spectra and suggests that such density spectra can be used to infer the presence of high-energy or low-energy precipitations based on spectral properties.

Due to the frequent climatic changes occurring worldwide, which are related to extreme meteorological parameters as well as human activities, it is obvious that these influence the flow regimes of rivers. River flow is the most important factor determining the hydrological regime of any river. This has a substantial influence on the water resources and the environment surrounding the river. Hydrotechnical structures are also dimensioned on the basis of the flow as the primary input parameter. The flow conditions have different properties and correlations with the material of the river bed. In this paper, possible dependencies and phenomena are investigated using real case studies on two rivers in Croatia - examples of river courses in alluvium and karst areas - with regard to homogeneity and isotropy analyses. For this purpose, rescaled adjusted partial sums and innovative polygon trend analysis methods will be applied on the form of a combination of methods at the same watercourses. It has been shown that the analysed time series of the flows do not exhibit homogeneity and isotropy. In addition, fluctuations and irregularities were detected in the same time series. This is key information for determining the reliability of the flow forecast.

Surveying (geodesy) and cartographic documentation, their types, and their flow (circulation) are the basis for the uniformity of the work carried out in the pre-design, design, and execution of construction works, ultimately having a representation in the operational (exploitation) and maintenance of railway infrastructure. The type and circulation of surveying and cartographic documentation constitute an important element for the transport sector. The aim of the present scientific research work was to define the state of irregularity of the standard of uniform surveying-cartographic documentation, their type, and their circulation (Ig-1) in interaction with rail transport problems. A case study method was used corresponding to a factual description, which aimed to analyze and evaluate the existing standard. This is important from a theoretical and, above all, a practical point of view. The results show an extensive space of irregularities occurring, violating legal regulations and professional ethics. At the same time, good practice solutions have been implemented to optimize the negative impact when interacting with rail transport problems. The authors’ position on the irregularities was forwarded to an infrastructure manager. The irregularities that occur significantly contribute to the limitations of surveying and cartographic documentation harmonization, and these have an impact on fully functional rail transport.

Polycystic Ovarian Syndrome (PCOS) is a complex endocrine disorder affecting reproductive-aged women, characterized by clinical manifestations such as hyperandrogenism, menstrual irregularities, and polycystic ovaries. Despite its prevalence and impact on women's health, the pathogenesis of PCOS remains incompletely understood. This review provides a comprehensive critical appraisal of existing literature on PCOS pathogenesis, addressing knowledge gaps and highlighting its multifactorial nature. A systematic literature review identified relevant articles published up to the knowledge cutoff date in 2023, focusing on molecular, genetic, hormonal, and environmental factors contributing to PCOS pathogenesis. Electronic databases, including PubMed, MEDLINE, and Embase, were systematically searched using predefined terms. Eligible studies investigated molecular, genetic, hormonal, and environmental factors associated with PCOS pathogenesis. The critical appraisal revealed diverse studies enriching our understanding of PCOS. Molecular and genetic studies highlighted alterations in signaling pathways, hormonal dysregulation, and the role of insulin resistance. Environmental factors, including lifestyle and exposure to endocrine-disrupting chemicals, were implicated. Heterogeneity in study designs and methodologies underscored the need for standardized approaches to enhance comparability. This review synthesizes current evidence on PCOS critical appraisal and pathogenesis, emphasizing its multifaceted nature. Standardization of study designs and methodologies will facilitate future comparisons, enabling the development of targeted therapeutic interventions and personalized management strategies for women affected by PCOS.

This article examines the mandate of Forensic Investigations Unit in the fight against fraud, corruption, financial misconduct, irregularities, and maladministration in the public sector of South Africa. Fraud, corruption, financial misconduct, irregularities and maladministration in public service have dire consequences to the lives of ordinary South Africans as these offences derail government efforts of improving the delivery of services such as construction of roads, access to clean water, electricity and housing. Thus, section 85(b) of the Public Finance Management Act, 1 of 1999 (PFMA) requires the Minister of Finance to craft regulations stipulating matter relating to the investigations of allegations of financial misconduct. The study employed a qualitative research approach including thoroughly revised several legislations such as Acts, regulations, policies and frameworks. Eight (8) participants from Forensic Investigations Units ranging from state departments/ institutions were interviewed using open-ended interview questions. The study followed purposive sampling as participant were selected purposively. The study found that it is the responsibility of Minister of Finance to craft regulations stipulating matter relating to the investigations of allegations of financial misconduct in the public sector. The study recommends the amended of Public Service Act of 1994 (PSA) interchangeable with Part three of Public Service Regulations of 2016 (PSR), PFMA and Treasury Regulations of 2001 to provide a Forensic Investigations Unit with clear mandate as these Acts and regulations remain silent on investigations performed by internal Forensic Investigations Units of the government departments/ institutions including State-Owned Entities (SOEs).

The study of issues related to the study of the state of the soil on the surface of the most constant technological track is relevant, since the movement of the running wheels along narrow tracks determines the traction and coupling properties of machine-tractor units, their vibrations, the stability of movement and the controllability of movement. The рurpose of this study was to increase the efficiency of the process of profiling microroughnesses of the soil surface located in areas that form a track along which the running wheels of machine-tractor units will move, by substantiating a new scheme of an automated profilograph and developing methods for its use. For this study, modern methods of experimental research based on IT technologies were used. In particular, an automated complex has been developed for measuring and evaluating the microprofile of soil surface irregularities on the very track of the tramline. The results of the experimental studies in this matter showed that the standard deviation of the soil surface irregularities reaches ±0.84 cm. This gives reason to consider the harmonic components of these functions as damped, having normalized correlation functions. The graphs constructed using PC showed that most of the dispersions of soil surface irregularities on the ruts themselves are concentrated in the range of 0…0.3 sm-1. It was established that the generator of the formation of irregularities in the longitudinal profile of traces of a permanent technological track is the parameters of the treads of the wheels of the machines moving along it. The obtained results of the study can be used in the selection of protectors of pneumatic tires of the running wheels of machine-tractor units moving on two tracks

About the importance of food products, probably not much needs to be said. Regardless of the country, people's life is not possible without the consumption of food products. Like any other products, food products must have labels. The role of labels is basically the same as for any product: the label must inform the buyer or consumer about several aspects. An incomplete or incorrect label of a food product can lead to dangers for buyers or consumers. The interest in labeling food products all over the world is a big one, due to the importance of food products. And it is normal to be like that. In order to protect the consumer, all countries must have an appropriate legislative and institutional framework. Modern countries have these two tools necessary to defend the interests of their citizens, who are both buyers and consumers. The legislation of each country regulates which details must appear on the labels of food products. This reality has been reached in time, as a result of advances in consumer protection, especially consumer information. Practice shows that there are many problems caused by food labeling, and problems occur in all countries, regardless of their degree of development. The problem of irregularities encountered by consumers in the labelling of food products remains one of continued interest, at a global level.

Abstract We develop a climatological model for the Arctic ionosphere based on more than one solar cycle of data (2010–2021) of the rate of change of the total electron content index (ROTI) maps from the International GNSS Service (IGS). The IGS ROTI maps are daily averaged in magnetic latitude and local time coordinates. To develop a climatological model, the ROTI maps are decomposed into base functions and coefficients using the empirical orthogonal function (EOF) method. The EOF method converges very quickly, and the first four EOFs reflect the majority (96%) of the total data variability. Furthermore, different EOF components can reflect different drivers of ionospheric irregularities. The first EOF reflects the averaged ROTI activity and the impact of the solar radiation and geomagnetic activity; the second EOF reflects the impact of the interplanetary magnetic field (IMF) Bz and electric field; the third and fourth EOFs reflect the dawn‐dusk asymmetry around the auroral oval and polar cap, and they can be related to the IMF By. To build an empirical model, we fit the EOF coefficients using helio‐geophysical indices from four different categories (solar activity; geomagnetic indices; IMF; the solar wind coupling function). The final EOF model is dependent on seven selected indices (F10.7P, Kp, Dst, Bt, By, Bz, and EKL). The statistical data‐model comparisons show satisfactory results with a good correlation coefficient. However, the model cannot capture the significant expansion of the dayside ROTI activity during strong geomagnetic storms. Future effort is needed to provide corrections to the model during severe storms.

In the South African government sector, public procurement is a strategic mechanism through which the government could be able to achieve the mandatory socioeconomic objectives. To this extent, the government procures goods and services from the private sector which can be estimated around eight hundred billion rand annually. Although there are numerous policy frameworks and systems to ensure that the management of the public procurement processes are fair, equitable, transparent, and cost-effective; the public procurement management practice, particularly in the delivery of construction goods and services, remains vulnerable to mismanagement and irregularities. To this extent, the nature of the irregularities and the stages at which they occur in the public procurement system remains unclear. To address this gap of knowledge, a content analysis method and the associated techniques of in-Vivo coding and word frequency analysis were used for the analysis of the secondary data. The study revealed that poor and or non-performance were the most frequent irregularities in the procurement of public construction services. The principal theoretical implication of this study is that rigorous proficiency measures should be applied to scrutinize and evaluate the potential of the contractors in terms of capacity to deliver in accordance with the contractual agreements prior to the awarding of contracts.

In the article action of the anisotropic irregularities in an ionosphere on a satellite channel is investi- gated. Relations between the exponent, characterising depth of fadings in a communication channel, with sta- tistical performances of the aniisotropic irregularities in an ionosphere are spotted.

There are presented the results of analysis of some irregularities in the series of displacement coordinates on the Earth’s surface for the geographic North Pole in order to relate them temporally to some global jerks in the geomagnetic field. The calculations were made using the International Earth Rotation and Reference Systems Service (IERS) data on the average daily motions of the North Pole from 1962 to 2021 and the information on global jerks in the geomagnetic field measured by the magnetic observatories throughout the world. The identification and analysis of the irregularities in the pole displacement along the Earth’s surface were performed by the Fourier Method and wavelet methods for time series analysis, methods of fixed threshold determination and minimax analysis of the non-Gaussian noise, phase and pseudo-phase space methods, and stroboscopic methods of construction of Poincare maps.The analysis of local Fourier spectra and wavelet-spectra reveals irregularities in the displacement of the North Pole in the time intervals from 1967.04.09 to 1967.11.30, from 1974.03.29 to 1974.09.12, and from 2005.11.03 to 2006.03.07. It is supposed that energy reconstructions which caused short-term pole deviations from the trajectory and starting to follow its previous trajectory at the return points are related to the specific features of oscillatory interactions in the process of the translational-rotational motion of the Earth’s in the Solar System. The time of marking specific points on graphs of the displacement of the pole along the surface of the Earth in 1967 and 1974 is ahead of global geomagnetic jerk occurrence times.

In the frame of this work, a robotic Automated fiber placement - AFP in situ process was applied to obtain high quality thermoplastic composite structures. Automated fiber placement (AFP) with laser assisted heating (LAFP) is an attractive manufacturing technology for the development of lightweight and high performance components, primarily for the aerospace, automotive, military and many other dominant industries worldwide. For the samples laminate plates produced with the AFP procedure, the flexural strength was investigated, and optical images were analyzed for irregularities such as pore content and weaker interlaminar bonding between the layers.

Public procurement is an area very vulnerable to corruption, which was especially evident during the Covid-19 virus pandemic. Pandemic called for prompt state response, including urgent public procurement procedures that resulted in numerous irregularities (e.g., “Silver Raspberry” case). The possibility of discretionary decision-making contributed to irregularities, and the absence of financial controls, which due to the urgency of the procedure could not be implemented in a timely manner. Therefore, if financial control systems are not able to function smoothly, the question of modalities of strengthening transparency and control in public procurement procedures arises. One possibility to inform the public about irregularities is through whistleblowers. However, this also depends on the level of whistleblower protection in respective national legislation. Whistleblowers in public procurement can face a variety of challenges. Starting from the assumption that the protection of whistleblowers and the whistleblowing process itself needs to be further improved, authors offer recommendations for improving the position of whistleblowers in public procurement procedures at the national level of European countries based on the application of dogmatic-legal method and content analysis.

The main objective of this study is to analyze the regulation of the State of Alarm (requirements and procedure for its adoption), by relating it to the demands arising from the principle of proportionality, made up of the sub-principles of necessity, suitability and proportionality in the strict sense and, this, for the purpose of determining whether the declaration in Spain, in 2020, of the State of alarm on the occasion of the Coronavirus, as well as the measures adopted with the declaration itself and its subsequent course, may pose doubts of legality and generate, by extension, problems, especially from the point of view of the responsibility of the Government in the near future.

The collapse and damage of large number of buildings during the November 26, 2019 (Mw 6,4) Albania earthquake caused 51 fatalities and injuries to at least 910 people. Most of collapsed or heavily damaged buildings were RC frame buildings. Although RC frame system is considered as very ductile seismic force-resisting system, its behaviour during earthquake highly depends on: (1) regularity in plan and elevation, and (2) global and local ductility. Based on the authors' visit to the earthquake-affected area on behalf of the Serbian Association of Earthquake Engineering and observations of collapsed and damaged buildings, it was concluded that among main reasons for underperformance of these flexible systems were inadequate analysis of interaction between infill walls and RC frames and reinforcement detailing of RC members.

Nematic liquid crystal planar and smoothly-irregular waveguide structures were studied experimentally and by the computer modeling. Two types of optical smoothly-irregular waveguide structures promising for application in telecommunications and control systems are studied by numerical simulation: liquid crystal waveguides and thin film solid generalized waveguide Luneburg lens. Study of the behavior of these waveguide structures where liquid crystal layer can be used to control the properties of the entire device, of course, promising, especially since such devices are also able to perform various sensory functions when changing some external parameters, accompanied by a change in a number of their properties. It can be of interest to researchers not only in the field of the integrated optics but also in some others areas: nano-photonics, optofluidics, telecommunications, and control systems. The dependences of the attenuation coefficient (optical losses) of waveguide modes and the effective sizes (correlation radii) of quasi-stationary irregularities of the liquid-crystal layers on the linear laser radiation polarization and on the presence of pulse-periodic electric field were experimentally observed. An estimate was made of the correlation radii of liquid-crystal waveguide quasi-stationary irregularities. The obtained results are undoubtedly important for further research of waveguide liquid crystal layers, both from the theoretical point of view, and practical – in the organization and carrying out new experimental researches, for example, when developing promising integrated-optical LC sensors.

Previous studies and observations of the earthquake have shown that frame filled with concrete 3d panel wall, can have adverse effects on the seismic behavior of structures. On the other hand, yielding dampers that used with steel braces, have a high capacity to absorb and depreciating energy from the earthquake. In this paper, targets are reducing damage to the infills and moment frame in during of the earthquake, reduce the horizontal and vertical irregularities in structure. To rech these targets, Three experimentally models with half scale were constructed and tested on the shaking table under 7 scale accelerated. Also, for investigate the Effective of parameters in the seismic behavior of moment frames, using Abaqus software, finite element analysis was performed after verification of model behavior with experimentally results. Experimentally results showed that use the yielding connection between wall and frame, reduces the lateral displacement and plastic strain in the structure. Numerical analyzes showed that by adding the yielding connection to the frame and infill wall, The frame has linear behavior In high intensity earthquake, and not be created plastic hinges in the members of the frame. The input energy is amortized only in the connections. So the number and geometric specification of these connections can affect the lateral hardness and lateral strength of the structure.

The foundations and the operating framework of the institutions of the European Union and its Member States are determined by legal acts established at the EU level. The legal bases at the EU level contain key standards in the scope of protection of the financial interests of the European Union and are the main determinants for the individual EU countries when their legal institutions create legal bases at the national level. The aim of this article is to present the main legal basis for the protection of the financial interests of the European Union at the EU level, which will help to examine the impact of these provisions on detecting irregularities and fraud in the EU.

External public audit of non-reimbursable EU funds involves the application of those specific audit procedures to obtain adequate and sufficient audit evidence regarding the legality and regularity of transactions, the completeness and accuracy of the data entered in the accounts, as well as the compliance of the management and control systems with the applicable regulations so that the audit opinion to be substantiated. The article presents essential aspects regarding the audit actions on EU non-reimbursable funds, summarizes the results of the audit activity carried out by the Audit Authority, with particular reference to the programming period 2007-2013, considering its completion, following the impact of the audit opinions through the irregularities or the frauds identified and the reporting to the European Commission, in view of using the audit results for continuing the financing process. The main responsibility for fraud prevention and detection lies with the managing authorities. However, the success of the fight against fraud depends on the joint efforts of managing and certification authorities, auditors and other stakeholders. Each participant in the chain must play its role in protecting the EU's financial interests.

Abstract We report the proposal and results of a low‐cost, easy‐to‐build GPS‐based sensor for detection and monitoring ionospheric irregularities through the detection of amplitude scintillation. The system is based on the Raspberry Pi single‐board computer combined with an Adafruit Ultimate GPS peripheral, which is capable of measuring (at 10‐Hz rate) the intensity of the L1 signals transmitted by GPS satellites. We introduce and discuss results of short‐ and long‐term observations obtained with a prototype of this system deployed in Presidente Prudente, a low magnetic latitude site in Brazil. The deployment and observations were carried out to test the ability of the system to detect ionospheric scintillations and, therefore, monitor the occurrence of ionospheric irregularities associated with equatorial spread F. Our results show that this low‐cost sensor is indeed capable of detecting scintillation events associated with equatorial spread F. Comparison with simultaneous, collocated measurements made by a commercial scintillation monitor are also presented. The joint observations allowed us to quantify the performance of the low‐cost monitor and to identify sources of potential limitations. While the sensor cannot (and it was not intended to) substitute commercial scintillation monitors, the low cost allows its use in studies of ionospheric irregularities (space weather) that require observations made by distributed arrays of small instruments (DASI). Furthermore, the simplicity of the sensor design stimulates its use in educational and citizen science initiatives.

One of the essentials aims of the ECA’s special report on fighting fraud in spending EU funds is improving the correlation between the European Union law and national legal systems of Member States and developing cooperation of EU authorities with Member States in its implementation. The first part of the article describes the basic regulations of the EU law on fighting against financial fraud in spending EU budget funds. In the second part, the assessment of operations of the EU bodies (especially the European Commission) and suggested recommendations are presented. The example of Poland describes a diversified situation in the matters of fighting financial fraud in the EU spending in particular Member States.

Romania’s accession to the European Union has opened new horizons for our country from the perspective of recovering the economic gaps that exist between us and the Member States. The 12 years have meant a lot of work, representing an effort made by both the governors and the direct beneficiaries. The absorption capacity of the European funds has gradually increased from one year to the next between 2007 and 2015. Thus, for example, in terms of the total amounts received from the EU budget the differences from one year to another are significant: 417.02 million euro in 2007; 641.92 million euro in 2008; 909.12 million euro in 2009, 505.73 million euro in 2010, reaching 2884.47 million euro in 2013, 3536.81 million euro in 2014, 2591.36 million euro in 2015 and 3663.96 million euro in 20162. The question that arises is whether or not this money has contributed decisively to diminishing the gaps between Romania and the countries of the western European Union. The irregularities detected by the Managing Authorities and the Audit Authority in the procurement procedures carried out within the projects financed by these funds only confirm that this money has not always been directed where it is needed.

The equatorial plasma bubble (EPB) phenomenon is an important component of space weather as the ionospheric irregularities that develop within EPBs can have major detrimental effects on the operation of satellite-based communication and navigation systems. Although the name suggests that EPBs occur in the equatorial ionosphere, the nature of the plasma instability that gives rise to EPBs is such that the bubbles may extend over a large part of the global ionosphere between geomagnetic latitudes of approximately ±15°. The scientific challenge continues to be to understand the day-to-day variability in the occurrence and characteristics of EPBs, such as their latitudinal extent and the development of irregularities within EPBs. In this paper, basic theoretical aspects of the plasma processes involved in the generation of EPBs, associated ionospheric irregularities, and observations of their characteristics using different techniques will be reviewed. Special focus will be given to observations of scintillations produced by the scattering of VHF and higher frequency radio waves while they propagate through ionospheric irregularities associated with EPBs, as these observations have revealed new information about the non-linear development of Rayleigh–Taylor instability in equatorial ionospheric plasma, which is the genesis of EPBs.

Abstract The midlatitude ionospheric trough (MIT) is a well‐known feature in the topside ionosphere. Previous MIT related studies mainly focused on the MIT structure itself, while few studies focused on irregularities inside the MIT region. In this study, we provided for the first time the magnetic latitude and magnetic local time distribution of irregularities within the MIT, by using the Swarm in situ plasma measurements. Orbital cases show that both the MIT equatorward and poleward walls are embedded with small‐scale irregularities. Further statistical analysis reveals that the particle precipitation is the dominant mechanism for the dayside MIT region irregularities, while nightside MIT region irregularities are strongly related with the temperature gradient drift instability. The Swarm observations show that the temperature gradient drift instability occur not only in MIT equatorward wall but also in MIT polarward wall, which is different to the theoretical prediction of Hudson and Kelley (1976, https://doi.org/10.1029/JA081i022p03913).

Abstract While low and high‐latitude ionospheric scintillation have been extensively reported, significantly less information is available about the properties of and conditions leading to mid‐latitude scintillations. Here, we report and discuss scintillation observations made in the Southern United States (UT Dallas, 32.99°N, 96.76°W, 43.2°N dip latitude) on June 1st, 2013. The measurements were made by a specialized dual‐frequency GPS‐based scintillation monitor which allowed us to determine main properties of this mid‐latitude scintillation event. Additionally, simultaneous airglow observations and ionospheric total electron content (TEC) maps provided insight on the conditions leading to observed scintillations. Moderate amplitude scintillations (S4>∼0.4) occurred in both L1 and L2C signals, and severe (S4 > ∼0.8) events occurred in L2C signals at low (

Abstract Daytime equatorial spread F (ESF) is not as common as nighttime ESF due to the presence of a highly conducting E‐layer during the daytime which counteracts the development of F‐layer plasma irregularities. This study presents two rare daytime ESF‐like events which occurred over an interval ∼2 h and were detected by the HF Doppler receiver located in Lagos (LAG: geographic: 3.27°E, 6.48°N; dip latitude −1.72°) and the Lowell Digisonde at Ilorin (ILR; 4.68°E, 8.50°N; dip latitude −1.25°), managed by Lowell GIRO Data Center (LGDC). Analysis of the first event revealed ∼30 min periodic oscillations in iso‐heights of ionospheric electron density. Shorter period (∼15 min) oscillations appeared simultaneously in HF Doppler measurements and these oscillations lasted nearly 3 h. Close inspection of the ionograms from ILR during this interval (1500–1800 UT) showed the occurrence of small‐scale spreading in the F‐layer trace which varied in altitude as the disturbance progressed. Computation of the linear growth rate of the collisional Rayleigh‐Taylor instability showed that the plasma instability was seeded by a traveling ionospheric disturbance (TID). The characteristics of the second event suggest that horizontal stratifications in plasma density distribution at the reflecting ionospheric layer were responsible for the spread F traces in the ionograms. Analysis of GPS TEC data from Nigeria during these events revealed the presence of wave structures consistent with TIDs.

This study examines procurement irregularities, as one of the most unexplored threats in the procurement process of construction projects. It also tests the suppositions associated with the contributions of irregularities to corruption in construction procurement. An expert survey is conducted with 62 construction-related practitioners selected via non-probabilistic sampling in the context of a Ghana, to assess the criticalities of the irregularities. Eighteen irregularities were identified within the context selected for this study. A soft computing technique known as the Fuzzy Synthetic Evaluation (FSE) method is employed to examine the identified irregularities. Other relevant techniques including factor analyses, normalization, and descriptive tools are employed to factorize the identified irregularities and test the hypotheses. Out of the 18 irregularities, 11 were revealed to be critical. The findings reveal that the top three irregularities were: payments for uncompleted works, sourcing of proforma invoices from the same supplier and the lack of proper coordination among key departments. Moreover, four constructs were developed using the identified measurement items. They are administrative-specific, procedural, compliance and contract monitoring irregularities. Out of the four, the topmost critical construct turns out to be compliance irregularities. Theoretically, this study advances the scholarship of construction by shedding lights on the irregularities associated with the procurement processes of construction projects. It also contributes to an in-depth understanding of the noted irregularities. In practical terms, this study contributes to the procurement planning and policy-making process, it assists decision makers in putting in place measures to prevent or extirpate the likelihood of any of the irregularities’ occurrences.

This study presents observations of nighttime spread F/ionospheric irregularities and spread Es at low and middle latitudes in the South East Asia longitude of China sectors during the recovery phase of the 7–9 September 2017 geomagnetic storm. In this study, multiple observations, including a chain of three ionosondes located about the longitude of 100°E, Swarm satellites, and Global Navigation Satellite System (GNSS) ROTI maps, were used to study the development process and evolution characteristics of the nighttime spread F/ionospheric irregularities at low and middle latitudes. Interestingly, spread F and intense spread Es were simultaneously observed by three ionosondes during the recovery phase. Moreover, associated ionospheric irregularities could be observed by Swarm satellites and ground-based GNSS ionospheric TEC. Nighttime spread F and spread Es at low and middle latitudes might be due to multiple off-vertical reflection echoes from the large-scale tilts in the bottom ionosphere. In addition, we found that the periods of the disturbance ionosphere are ~1 h at ZHY station, ~1.5 h at LSH station and ~1 h at PUR station, respectively. It suggested that the large-scale tilts in the bottom ionosphere might be produced by LSTIDs (Large scale Traveling Ionospheric Disturbances), which might be induced by the high-latitude energy inputs during the recovery phase of this storm. Furthermore, the associated ionospheric irregularities observed by satellites and ground-based GNSS receivers might be caused by the local electric field induced by LSTIDs.

CH4 is a typical and special detonation mixture. Based on the experimental method, digital image processing was performed to study the detonation stability theory of methane. A premixed CH4 + 2O2 mixture was ignited in a tube with an inner diameter of 50.8 mm under different initial pressures. Smoked foils were used to record the cellular structure of spinning detonation. The average detonation velocity measured is similar with the CJ detonation velocity and it demonstrates that steady detonation happens when the initial pressure is higher than 5 kPa. The triple point trajectory leaves a very irregular pattern in smoked foils. In order to decrease human error, the digital processing technology was utilized and improved. The CH4 + 2O2 mixture shows high degree of irregularity in the computation of histograms and the autocorrelation function. The cellular size and gap of the unstable premixed CH4 + 2O2 were given. It is found that the results measured by digital image processing are accurate and by eyes are too big. The research can calculate the cellular size and the degree of instability of the unstable premixed CH4 + 2O2 and improves the quantitative irregular calculation method.

Public procurement is an important part of the current economic reality. The economic development of Romanian companies taking part in the bidding process closely depends on the national public system and it cannot be achieved without an efficient and correct procurement process. This study is focused on the irregularities found as a result of a complex research regarding the public procurement system. The main objective of this research is to build a model- an applicable strategy for identifying irregularities in procurement procedures and, as such avoiding them, by taking into consideration the particularities of the bidding process, its content and methods. The number of procurement appeals gives information about participant companies’ level of dissatisfaction, while the number of the admitted appeals shows the real leaks from the system. Considering these aspects, the current paper discusses about the public procurement process and it presents the critical phases of the public procurement procedure, by emphasizing the possible weaknesses and activities that can generate irregularities in this area. Thus, by analyzing the content of many officially admitted complaints related to the public bidding process, the paper reveals the main problematic aspects of the public procurement system, contributing thus to improvement and increased satisfaction for all participants taking part in the process.

Livelihood Empowerment Against Poverty (LEAP) is a flagship programme of the National Social Protection Strategy (NSPS) targeted at the vulnerable and extremely poor in Ghana. Based on the peculiar characteristics that the participants of the LEAP programme exude, a combination of non-probability sampling techniques was deployed, namely; purposive and snowballing. Using a qualitative research strategy under an interpretive philosophical paradigm, this paper explored how beneficiaries of the LEAP programme are riddled with certain irregularities which were identified in this paper to be an insufficiency of cash amount given, as well as the difficulty in accessing complimentary service. It is shown that these identified irregularities warrants a responds from the government judging from the fact that the beneficiaries who face these irregularities constitute the bottom 20 per cent of the poor in Ghana.

We analyze the amplitude scintillation on L-band signals over San Miguel de Tucumán (Argentina), focusing on the multi-scale variability and speculating on the possible relationship between forcing factors from the geospace and the ionospheric response. The site is nominally located below the expected position of the southern crest of the Equatorial Ionospheric Anomaly (EIA). For this scope, we concentrate on the period 1–31 March 2011, during which one minor and one moderate storm characterize the first half of the month, while generally quiet conditions of the geospace stand for the second half. By leveraging on the Adaptive Local Iterative Filtering (ALIF) signal decomposition technique, we investigate the multi-scale properties of Global Navigation Satellite Systems (GNSS) amplitude scintillation and helio-geophysical parameters, looking for possible cause-effect mechanisms relating the former to the latter. Namely, we identify resonant modes in the Akasofu (ε) parameter as likely related to the frequency components in the time evolution found for the amplitude scintillation index, hence modulating the scintillation itself.

Public procurement represents an important part of the current economy reality. The economical growth of the bidding Romanian companies is closely connected with the public system and cannot be possible without an efficient and correct procurement process. The number of the procurement appeals identifies informations about the satisfaction of the economic operators, while the admitted appeals show the irregularities from the system. This paper presents which are the critical phases of the public procurement procedure, in order to emphasize the weakness, to highlight possible activities that can generate irregularities in the process. According to the admitted complains, the paper shows the irregularities from public procurement system, which can be identified in time by the economic operators. This study is focused on the research of irregularities from public procurement system and the objective of the research is to compose an applicable strategy of identification and avoidance of irregularities from tender procurement procedures. It puts forward suggestions and opinions on the bidding process, content and methods.

To become a a net beneficiary of EU funds, Romania must ensure an absorption rate as higher as it can. The appreciation of the these funds' management and formulating opinions in support of improving the absorption of European funds in the future can be done with the audit because it is a guarantee for good performance by our country, but also by public authorities, of commitments which they have undertaken.

Plasma bubbles that occur in the equatorial F-region make up one of the most distinguishing phenomena in the ionosphere. Bubbles represent plasma depletions with respect to the background ionosphere, and are the major source of electron density irregularities in the equatorial F-region. Such bubbles are seen as plasma depletion holes (in situ satellite observations), vertical plumes (radar observations), and emission-depletion bands elongated in the north-south direction (optical observations). However, no technique can observe the whole three-dimensional structure of a bubble. Various aspects of bubbles identified using different techniques indicate that a bubble has a “shell” structure. This paper reviews the development of the concepts of “bubble” and “shell” in this context.

This manuscript presents a method to identify the occurrence of Equatorial Plasma Bubbles (EPBs) with data gathered from receivers of Global Navigation Satellite System (GNSS). This method adapts a previously existing technique to detect Medium Scale Travelling Ionospheric Disturbances (MSTIDs), which focus on the 2nd time derivatives of total electron content estimated from GNSS signals (2DTEC). Results from this tool made possible to develop a comprehensive analysis of the characteristics of EPBs. Analyses of the probability of occurrence, effective time duration, depth of the depletion and total disturbance of the EPBs show their dependence on local time and season of the year at global scale within the latitude belt from 35°N to 35°S for the descending phase of solar cycle 23 and ascending phase of solar cycle 24, 2002–2014. These results made possible to build an EPBs model, bounded with the Solar Flux index, that simulates the probability of the number of EPBs and their characteristics expected for a representative day at given season and local time (LT). The model results provided insight into different important aspects: the maximum occurrence of bubbles take place near the equatorial anomaly crests, asymmetry between hemispheres and preferred longitudes with enhanced EPBs activity. Model output comparisons with independent observations confirmed its soundness.

Scintillation is one of the most challenging problems in Global Navigation Satellite Systems (GNSS) navigation. This phenomenon appears when the radio signal passes through ionospheric irregularities. These irregularities represent rapid changes on the refraction index and, depending on their size, they can produce also diffractive effects affecting the signal amplitude and, eventually producing cycle slips. In this work, we show that the scintillation effects on the GNSS signal are quite different in low and high latitudes. For low latitude receivers, the main effects, from the point of view of precise navigation, are the increase of the carrier phase noise (measured by σϕ) and the fade on the signal intensity (measured by S4) that can produce cycle slips in the GNSS signal. With several examples, we show that the detection of these cycle slips is the most challenging problem for precise navigation, in such a way that, if these cycle slips are detected, precise navigation can be achieved in these regions under scintillation conditions. For high-latitude receivers the situation differs. In this region the size of the irregularities is typically larger than the Fresnel length, so the main effects are related with the fast change on the refractive index associated to the fast movement of the irregularities (which can reach velocities up to several km/s). Consequently, the main effect on the GNSS signals is a fast fluctuation of the carrier phase (large σϕ), but with a moderate fade in the amplitude (moderate S4). Therefore, as shown through several examples, fluctuations at high-latitude usually do not produce cycle slips, being the effect quite limited on the ionosphere-free combination and, in general, precise navigation can be achieved also during strong scintillation conditions.

The purpose of our analysis is to contribute to fighting fraud detrimental to the European Union's financial interests by the dissemination of the knowledge in the field of administrative measures for preventing fraud and irregularities related to the EU Structural funds. In this study we present some theoretical issues as well as the results of a comparative analysis between member states which offer some answers to the question about how much fraud is committed in the EU Structural funds and who are the “champions” of fraud in the last years. Our analysis is structured on 4 parts: a) Romania and the European Funds b) Irregularities and fraud in the management of the EU projects; c) Management tools of Member States to prevent frauds in EU funds- a comparative analysis; d) Conclusions regarding Romanian administrative measures to better prevention of cases of suspected fraud.

The objectives of the paper are both seismic instrumentation for damage assessment and enhancing of seismic resistance of buildings. In according with seismic design codes in force the buildings are designed to resist at seismic actions. Due to the time evolution of these design provisions, there are buildings that were designed decades ago, under the less stringent provisions. The conceptual conformation is nowadays provided in all Codes of seismic design. According to the Code of seismic design P100-1:2006 the asymmetric structures do not have an appropriate seismic configuration; they have disadvantageous distribution of volumes, mass and stiffness. Using results of temporary seismic instrumentation the safety condition of the building may be assessed in different phases of work. Based on this method, the strengthening solutions may be identified and the need of seismic joints may be emphasised. All the aforementioned ideas are illustrated through a case study. Therefore it will be analysed the dynamic parameter evolution of an educational building obtained in different periods. Also, structural intervention scenarios to enhance seismic resistance will be presented.

This paper investigates the relative scintillation level associated with cusp dynamics (including precipitation, flow shears, etc.) with and without the formation of polar cap patches around the cusp inflow region by the EISCAT Svalbard radar (ESR) and two GPS scintillation receivers. A series of polar cap patches were observed by the ESR between 8:40 and 10:20 UT on December 3, 2011. The polar cap patches combined with the auroral dynamics were associated with a significantly higher GPS phase scintillation level (up to 0.6 rad) than those observed for the other two alternatives, i.e., cusp dynamics without polar cap patches, and polar cap patches without cusp aurora. The cusp auroral dynamics without plasma patches were indeed related to GPS phase scintillations at a moderate level (up to 0.3 rad). The polar cap patches away from the active cusp were associated with sporadic and moderate GPS phase scintillations (up to 0.2 rad). The main conclusion is that the worst global navigation satellite system space weather events on the dayside occur when polar cap patches enter the polar cap and are subject to particle precipitation and flow shears, which is analogous to the nightside when polar cap patches exit the polar cap and enter the auroral oval.

A total solar eclipse occurred on 20 March 2015, with a totality path passing mostly above the North Atlantic Ocean, which resulted in a partial solar eclipse over Belgium and large parts of Europe. In anticipation of this event, a dedicated observational campaign was set up at the Belgian Solar-Terrestrial Centre of Excellence (STCE). The objective was to perform high-quality observations of the eclipse and the associated effects on the geospace environment by utilising the advanced space- and ground-based instrumentation available to the STCE in order to further our understanding of these effects, particularly on the ionosphere. The study highlights the crucial importance of taking into account the eclipse geometry when analysing the ionospheric behaviour during eclipses and interpreting the eclipse effects. A detailed review of the eclipse geometry proves that considering the actual obscuration level and solar zenith angle at ionospheric heights is much more important for the analysis than at the commonly referenced Earth’s surface or at the plasmaspheric heights. The eclipse occurred during the recovery phase of a strong geomagnetic storm which certainly had an impact on (some of) the ionospheric characteristics and perhaps caused the omission of some “low-profile” effects. However, the analysis of the ionosonde measurements, carried out at unprecedented high rates during the eclipse, suggests the occurrence of travelling ionospheric disturbances (TIDs). Also, the high temporal and spatial resolution measurements proved very important in revealing and estimating some finer details of the delay in the ionospheric reaction and the ionospheric disturbances.

The paper presents an analysis and evaluation of selected aspects of the enterprise X, there is shown the selection of the method of pro‐quality, which is possible to apply and this method was carried out step by step to follow its course and find out whether the company will bring tangible benefits.

Due to resource constraints, securities regulators cannot find or punish all firms that have conducted irregular or even illegal activities (hereafter referred to as fraud). Those who study securities regulations can only find the instances of fraud that have been punished, not those that have not been punished, and it is these unknown cases that would make the best control sample for studies of enforcement action criteria. China’s mandatory management earnings forecasts solve this sampling problem. In the A-share market, firms that have not forecasted as mandated are likely in a position to be punished by securities regulators or are attempting to escape punishment, and their identification allows researchers to build suitable study and control samples when examining securities regulations. Our results indicate that enforcement actions taken by securities regulators are selective. The probability that a firm will be punished for irregular management forecasting is significantly related to proxies for survival rates. Specifically, fraudulent firms with lower return on assets (ROAs) or higher cash flow risk are more likely to be punished. Further analysis shows that selective enforcement of regulations has had little positive effect on the quality of listed firms’ management forecasts.

The 2015 St. Patrick’s day storm was the first storm of solar cycle 24 to reach a level of “Severe” on the NOAA geomagnetic storm scale. The Norwegian Mapping Authority is operating a national real-time kinematic (RTK) positioning network and has in recent years developed software and services and deployed instrumentation to monitor space weather disturbances. Here, we report on our observations during this event. Strong GNSS (Global Navigation Satellite System) disturbances, measured by the rate-of-TEC index (ROTI), were observed at all latitudes in Norway on March 17th and early on March 18th. Late on the 18th, strong disturbances were only observed in northern parts of Norway. We study the ionospheric disturbances in relation to the auroral electrojet currents, showing that the most intense disturbances of GNSS signals occur on the poleward side of poleward-moving current regions. This indicates a possible connection to ionospheric polar cap plasma patches and/or particle precipitation caused by magnetic reconnection in the magnetosphere tail. We also study the impact of the disturbances on the network RTK and Precise Point Positioning (PPP) techniques. The vertical position errors increase rapidly with increasing ROTI for both techniques, but PPP is more precise than RTK at all disturbance levels.

This work presents a contribution to the understanding of the ionospheric triggering of L-band scintillation in the region over São Paulo state in Brazil, under high solar activity. In particular, a climatological analysis of Global Navigation Satellite Systems (GNSS) data acquired in 2012 is presented to highlight the relationship between intensity and variability of the total electron content (TEC) gradients and the occurrence of ionospheric scintillation. The analysis is based on the GNSS data acquired by a dense distribution of receivers and exploits the integration of a dedicated TEC calibration technique into the Ground Based Scintillation Climatology (GBSC), previously developed at the Istituto Nazionale di Geofisica e Vulcanologia. Such integration enables representing the local ionospheric features through climatological maps of calibrated TEC and TEC gradients and of amplitude scintillation occurrence. The disentanglement of the contribution to the TEC variations due to zonal and meridional gradients conveys insight into the relation between the scintillation occurrence and the morphology of the TEC variability. The importance of the information provided by the TEC gradients variability and the role of the meridional TEC gradients in driving scintillation are critically described.

The ROTI (Rate of TEC index) is a commonly used measure of ionospheric irregularities level. The algorithm to calculate ROTI is easily implemented, and is the same from paper to paper. However, the sample rate of the GNSS data used, and the time interval over which a value of ROTI is calculated, varies from paper to paper. When comparing ROTI values from different studies, this must be taken into account. This paper aims to show what these differences are, to increase the awareness of this issue. We have investigated the effect of different parameters for the calculation of ROTI values, using one year of data from 8 receivers at latitudes ranging from 59° N to 79° N. We have found that the ROTI values calculated using different parameter choices are strongly positively correlated. However, the ROTI values are quite different. The effect of a lower sample rate is to lower the ROTI value, due to the loss of high-frequency parts of the ROT spectrum, while the effect of a longer calculation time interval is to remove or reduce short-lived peaks due to the inherent smoothing effect. The ratio of ROTI values based on data of different sampling rate is examined in relation to the ROT power spectrum. Of relevance to statistical studies, we find that the median level of ROTI depends strongly on sample rate, strongly on latitude at auroral latitudes, and weakly on time interval. Thus, a baseline “quiet” or “noisy” level for one location or choice or parameters may not be valid for another location or choice of parameters.

We directly compare the relative GPS scintillation levels associated with regions of enhanced plasma irregularities called auroral arcs, polar cap patches, and auroral blobs that frequently occur in the polar ionosphere. On January 13, 2013 from Ny-Ålesund, several polar cap patches were observed to exit the polar cap into the auroral oval, and were then termed auroral blobs. This gave us an unprecedented opportunity to compare the relative scintillation levels associated with these three phenomena. The blobs were associated with the strongest phase scintillation (σϕ), followed by patches and arcs, with σϕ up to 0.6, 0.5, and 0.1 rad, respectively. Our observations indicate that most patches in the nightside polar cap have produced significant scintillations, but not all of them. Since the blobs are formed after patches merged into auroral regions, in space weather predictions of GPS scintillations, it will be important to enable predictions of patches exiting the polar cap.

Small scale ionospheric disturbances can lead to fluctuations of the received satellite signal, so-called signal scintillations. For global navigation satellite systems (GNSS) this reduces the positioning accuracy. Particular strong events can even lead to a loss of lock between satellite and receiver. All GNSS signals are affected by this phenomenon. The influence of the short scale disturbances on the different GNSS signals is expected to be different for each signal, since the signals are transmitted by different carrier frequencies and are constructed in different ways. In this paper, we compare the occurrence rate of signal scintillations between the different global navigation satellite systems and their different signal frequencies. In particular, we consider GPS L1, L2, and L5, GLONASS L1 and L2, and Galileo E1 and E5a. This analysis uses data from a high-rate GNSS station of the German Aerospace Center (DLR) placed in Bahir Dar, Ethiopia at 11°36′ N 37°23′ E. The station collects 50 Hz raw data from which the amplitude scintillation index S4 is calculated. The data has been collected for the whole year 2013. Since the number of strong scintillation events with S4 > 0.5 was smaller than expected, additionally weak scintillation events with S4 ≥ 0.25 are taken into account. An algorithm is used that provides a soft barrier for S4 ≥ 0.25. The resulting events are shown as daily and seasonal averages. Finally, the overall influence of short scale ionospheric disturbances in the form of signal scintillations on the GNSS signals is estimated.