Journal articles on the topic 'Avoiding cones conditions'

The advanced technique of shock-kinematic analysis of the bit roller cone interaction with rock in the process of oil and gas wells drilling is proposed. Preliminary investigations of the interaction of the roller cone bits with rock were based on assumptions far from reality: the concept of the instantaneous axis of rotation of the roller cone constant contact with rock, the absence of slipping, as well as the tooth reforming and sinking into rock. The principle of the roller cones action is the gradual destruction of the surface of the bottomhole due to the cutting-crushing chipping of rock with a bit tooth.The axial roller cone is considered, and the original method of planes projection is used to determine the regulation of tooth motion, taking into account: bit roller cones slipping along the surface of the bottomhole; phases of roller cone tooth sinking into rock; real change in the distance of the axis of rotation of the roller cone to the surface of the bottomhole due to tooth penetration into the rock; the substantiation of the conditions for avoiding the roller cone tooth entering to the previously obtained hole in the process of bottomhole crushing. Besides the moment of the drill string inertia, the moments of roller cones inertia are additionally taken into account under the condition of the oblique impact of the tooth on the rock.The technique allows to calculate the volume of the disintegrated rock on the bottomhole, both taking into account and without taking into account rock chipping and tooth forming. The obtained dependencies allow us to select transmitted ratios from the drill string to the crowns of the roller cones under the condition of avoiding the roller cone tooth to the previously obtained hole during rock destruction on the bottomhole. It allows increasing the efficiency of drilling by roller cones.

The lane change of vehicles for avoiding hitting a sudden obstacle represents a significant and unique problem for traffic accident experts. Most mathematic models for determining the lane change distance are based on theoretical research studies and a lot of simplifications and approximations. In order to analyse the influence of different drivers and vehicles on a manoeuvre, an experimental research study of lane change was carried out at the test track which enables repeatability in the same conditions. The drivers were instructed to drive through the test track at a maximum speed without displacing the traffic cones. Based on the statistical analyses of the successful lane change manoeuvres an empirical model for the calculation of lane change distance for obstacle avoidance was formed. This model can be applied in the procedure of traffic accident reconstructions as well as within the development of the concept of modern intelligent vehicles.

Zero-dimensional/one-dimensional computational fluid dynamics codes are used to simulate the performance of complete internal combustion engines. In such codes, the operation of a turbocharger compressor is usually addressed employing its performance map. However, simulation of engine transients may drive the compressor to work at operating conditions outside the region provided by the manufacturer map. Therefore, a method is required to extrapolate the performance map to extended off-design conditions. This work examines several extrapolating methods at the different off-design regions, namely, low-pressure ratio zone, low-speed zone and high-speed zone. The accuracy of the methods is assessed with the aid of compressor extreme off-design measurements. In this way, the best method is selected for each region and the manufacturer map is used in design conditions, resulting in a zonal extrapolating approach aiming to preserve accuracy. The transitions between extrapolated zones are corrected, avoiding discontinuities and instabilities.

Both efficiency and cavitation performance of the hydrofoil are the key technologies to design the tidal current turbine. In this paper, the hydrofoil efficiency and lift coefficient were improved based on particle swarm optimization method and XFoil codes. The cavitation performance of the optimized hydrofoil was also discussed by the computational fluid dynamic. Numerical results show the efficiency of the optimized hydrofoil was improved 11% ranging from the attack angle of 0-7? compared to the original NACA63-818 hydrofoil. The minimum pressure on leading edge of the optimized hydrofoil dropped above 15% at the high attack angle conditions of 10?, 15?, and 20?, respectively, which is benefit for the hydrofoil to avoiding the cavitation.

Architectural heritage masonry buildings located in seismic areas are highly prone to suffer damage under seismic loading, due to their structural features. In this study, the Salares medieval tower, which is placed in the province of Malaga (Spain) - a zone with high seismic hazard in the Iberian Peninsula- is adopted as a case study. This is a precious heritage building which exhibits severe damages, such as depth cracks and inclination. Owing to those reasons detailed seismic and dynamic analyses are crucial for its preservation. The present work is arranged in three sections that deal with seismic hazard analysis, selection of real acceleration time-histories representative of the site, and dynamic response by means of numerical models. In order to obtain the design earthquake at the specific location, different parameters were analyzed, namely the region seismic activity, the geotechnical and geological conditions at the site and the acceptable risk level. Hazard analysis was performed following deterministic and probabilistic methods. As far as the seismic input is concerned, real accelerogram representative of the 1884 Andalusia earthquake were selected. It was a destructive earthquake that caused catastrophic damages near the analyzed structure. The accelerograms thus obtained were used as input for subsequent non-linear dynamic analyses on three-dimensional finite element models. Different cracking capable constitutive models were considered in order to predict local and global collapse mechanisms. Moreover, the suitability of each model was discussed when crushing, high plastic deformation or response under cyclic loading are concerned. The aforementioned studies yield significant results in order to perform a comprehensive safety assessment under ground motion effects. Thus, regarding the seismic input, the obtained accelerogram provides a relevant application aimed at revising the maximum acceleration and the response spectra of the Codes, as seismic code recommendations are limited in those issues. Furthermore, the dynamic structural response via numerical approach, allows determining damage propagation and collapse probability as a main step to select appropriate repair measures. The followed method could be used to assess and improve the structural strength of similar architectural heritage buildings located in active seismic areas.

Character recognizers have generally focused on printed text on paper with an emphasis on generality rather than speed. This makes the proposed algorithms not applicable in the context of the very high-speed industrial validation of expiration codes printed on the metal surface of a can. The extreme demands of speed and the adverse effects of lighting and movement, among other things, make it necessary to develop an original and specific strategy. The strategy presented in this paper first selects which of the segmented shapes of a printed can are the best candidates for comparison with expected characters. This is followed by a technique based on the comparison of templates (templates matching), which we call “morphologies”, and are represented as bitmaps to take advantage of the hardware capabilities of general-purpose processors. The use of templates has the advantage of avoiding the construction of a feature vector. In an acquisition test in a real industrial plant, we have been able to successfully treat 438 cans in 44 s, with only one validation error in one character, achieving a compromise between speed and quality that is sufficient for industrial validation in the conditions cited.

INTRODUCTION: Oral conditions such as dental caries, periodontal diseases, tooth loss and trauma affect millions of people globally. These conditions can be prevented when detected early, thereby avoiding adverse outcomes. The prevalence of oral conditions has been reported in most provinces. However, there is a paucity of data in KwaZulu-Natal. AIM AND OBJECTIVE: This study aimed to determine the prevalence of oral conditions at public health facilities in two health districts in KwaZulu-Natal, South Africa. MATERIALS AND METHODS: A cross-sectional analytical study design was used to determine the nature of oral conditions treated in dental facilities in the eThekwini and uMgungundlovu districts, in KwaZulu-Natal. The study was conducted over a 5-month period (November 2018 - April 2019). After clinicians examined the patients they entered the data in the patients clinical records and selected information (routine medical history questions as well as 16 possible diagnosis codes) were entered into a data extraction template. The data were analyzed using statistical software SPSS. RESULTS: Dental caries was the most prevalent oral condition at 66.4% followed by periodontal disease at 11.7%, trauma at 7.3% and lastly tooth loss at 5.9% CONCLUSION: These findings contribute to knowledge on the prevalence of these oral conditions found in the province.

The construction of numerical solutions of Einstein's General Relativity equations is formulated as an initial-value problem. The space-plus-time (3 + 1) decomposition of the spacetime metric tensor is used to discuss the structure of the field equations. The resulting evolution system is shown to depend in a crucial way on the coordinate gauge. The mandatory use of singularity avoiding coordinate conditions (like maximal slicing or similar gauges) is explained. A brief historical review of Numerical Relativity is included, showing the enormous effort in constructing codes based in these gauges, which lead to non-hyperbolic evolution systems, using "ad hoc" numerical techniques. A new family of first order hyperbolic evolution systems for the vacuum Einstein field equations in the harmonic slicing gauge is presented. This family depends on a symmetric 3 × 3 array of parameters which can be used to scale the dynamical variables in future numerical applications.

BACKGROUND: Exposure to artificial stone machining, under the conditions in which marble workers work with this new product, can cause silicosis. OBJECTIVE: To examine the experiences of marble workers affected, both in workshop and during home installation of countertops, before diagnosis of silicosis. METHODS: Qualitative study in which 10 open-ended semistructured interviews were conducted with marble workers diagnosed with silicosis after machining artificial stone countertops in Cádiz, Spain. Interviews were recorded, transcribed, and coded using a directed content analysis. Codes were organized into themes. RESULTS: Interviews up to 120 minutes and transcript analysis revealed three themes: 1) Heavy exposure for piecework: construction boom in an environment of labor deregulation and high demand for the novel product; 2) Poor working conditions: dry machining of artificial stone without proper protection in the workshop and greater exposure during home installation of countertops; 3) Concatenated legal transgressions: deficiencies in prevention and health surveillance without safety conditions for the correct handling of artificial stone. CONCLUSIONS: The fight against an emerging occupational disease—artificial stone silicosis—should focus on detecting affected workers and avoiding new cases, forcing joint efforts to achieve rigorous compliance with health surveillance and protecting marble workers to achieve healthy and safe workplaces.

Historically, in high-risk patients with cardiovascular disease, anticoagulants have been used in order to reduce the risk of stroke or other ischemic complications. However, despite this seemingly simple solution, drug selection and dosage control may provide a unique challenge when it comes to the anticoagulation therapy of individual patients. In this case report, a patient with multiple underlying conditions and two previous stroke episodes was admitted due to decompensated heart failure and was treated with anticoagulants to reduce the risk of developing secondary stroke(s). The initially prescribed anticoagulative agent, acenocoumarol, was discontinued and subsequently replaced with enoxaparin due to unstable INR and undiagnosed anaemia. Unfortunately, newer anticoagulants were contraindicated in this patient due to the previous implantation of the mechanical aortic valve. This study reveals and discusses the conundrum faced in prescribing anticoagulants to patients with multiple conditions of underlying diseases. Despite the aforementioned hurdles, anticoagulant therapy in these patients is crucial in avoiding potential life-threatening complications, including myocardial infarction and secondary stroke; proper prescription decisions may ultimately decrease morbidity and improve the quality of life of these high-risk patients.

If an accident happens, nature of the humans is to criticize somebody else instead understanding the mistake. Finally, European study says that in 80% of vehicle accidents especially motor vehicles, drivers criticize the other person instead of preventing the accident. In our assessment, we consider conditions of traffic in India. For any accident to happen, major cause is speed of the driver. So, we should go for new methods to eradicate such type of problems. Assessment of accidents are done to identify the reason or series of accidents that are occurred and to avoid fresh accidents of the same type. So, we are going for Self-sustained Debacle Repression method identified by the combination of different independent solutions. An SDR development shape tomorrow’s safe. It also comes with collision avoidance Mechanisms such as: Avoiding the collision using Ultrasonic Sensor and ARM processor and Collision Indication (car-to-Xs Communication) using ZIGBEE technology.

Advances in building-integrated photovoltaic (BIPV) systems for residential and commercial purposes are set to minimize overall energy requirements and associated greenhouse gas emissions. The BIPV design considerations entail energy infrastructure, pertinent renewable energy sources, and energy efficiency provisions. In this work, the performance of roof/façade-based BIPV systems and the affecting parameters on cooling/heating loads of buildings are reviewed. Moreover, this work provides an overview of different categories of BIPV, presenting the recent developments and sufficient references, and supporting more successful implementations of BIPV for various globe zones. A number of available technologies decide the best selections, and make easy configuration of the BIPV, avoiding any difficulties, and allowing flexibility of design in order to adapt to local environmental conditions, and are adequate to important considerations, such as building codes, building structures and loads, architectural components, replacement and maintenance, energy resources, and all associated expenditure. The passive and active effects of both air-based and water-based BIPV systems have great effects on the cooling and heating loads and thermal comfort and, hence, on the electricity consumption.

To simulate the mode of the RCP starting in an earlier inoperative loop, KORSAR/GP, a code supporting coupled numerical modeling of neutronic and thermal-hydraulic transients in a VVER reactor plant in operating and emergency conditions, was chosen as the computational tool. Studying these modes using thermal-hydraulic codes makes it possible to analyze the course of transients and certain emergency processes without using commercial test procedures, which contributes to laying the groundwork for addressing the issues involved in ensuring the reliability, operating safety and efficiency of nuclear power plants. Increased requirements to the safety of NPPs identify the need for avoiding excessive conservatism in the analysis based on which requirements to safety systems are formulated, as well as for enhancing the knowledge of the regularities of thermal-hydraulic transients based on advanced computer programs (or codes) designed for improved computational analysis of non-stationary thermal hydraulics in the water-cooled reactor circulation circuits in emergency and transient modes relying on inhomogeneous non-equilibrium mathematical models of two-phase flows and on a detailed description of the physical transient regularities. The purpose of the study is to analyze computationally the starting of a VVER-1000 RCP in an earlier inoperative loop at different reactor plant power values. To do this, one requires to develop the VVER-1000 reactor primary circuit computational pattern to model the transient taking place as one RCP is started, to conduct a further analysis, and to compare the key monitored reactor coolant and core parameters (power, temperature, flow rate, etc.).

Power electronic converters for power factor correction (PFC) play a key role in single-phase electrical power systems, ensuring that the line current waveform complies with the applicable standards and grid codes while regulating the DC voltage. Its verification implies significant complexity and cost, since it requires long simulations to verify its behavior, for around hundreds of milliseconds. The development and test of the controller include nominal, abnormal and fault conditions in which the equipment could be damaged. Hardware-in-the-loop (HIL) is a cost-effective technique that allows the power converter to be replaced by a real-time simulation model, avoiding building prototypes in the early stages for the development and validation of the controller. However, the performance-vs-cost trade-off associated with HIL techniques depends on the mathematical models used for replicating the power converter, the load and the electrical grid, as well as the hardware platform chosen to build it, e.g., microprocessor or FPGA, and the required number of channels and I/O types to test the system. This work reviews state-of-the-art HIL techniques and digital control techniques for single-phase PFC converters.

Perceived shortcomings in NZS 1170.5 [1] and some other Standards are highlighted and areas for improvement are suggested. A particular focus is placed on achieving the principal objective of achieving life safety at the limit state at which structural collapse is to be avoided. Topic areas commented on include: The objectives of earthquake resistant design, especially that of avoiding the collapse of structures The appropriateness of current classifications of buildings into importance levels The currency and adequacy of the design seismic hazard spectra requirements The justification for, and application of, a structural performance factor The force-based and displacement-based methods of analysis and design, and the effects of plastic hinging relieving member permanent load moments at plastic hinges adjacent to points of support Consideration of displacement effects, and effects on displacements, at the limit state at which collapse is to be avoided Achieving reparability Some shortcomings in the material Standards for both structural steel and reinforcing steel Consideration of site conditions, and in coastal locations the tsunami risk Comparability of New Zealand design requirements with other major design codes.

ObjectiveTo determine the proportion of children and young people (CYP) in England who are readmitted for the same condition.DesignRetrospective cohort study.SettingNational administrative hospital data (Hospital Episode Statistics).ParticipantsCYP (0-year-olds to 24-year-olds) discharged after an emergency admission to the National Health Service in England in 2009/2010.Main outcome measuresCoded primary diagnosis classified in six broad groups indicating reason for admission (infection, chronic condition, injury, perinatal related or pregnancy related, sign or symptom or other). We grouped readmissions as ≤30 days or between 31 days and 2 years after the index discharge. We used multivariable logistic regression to determine factors at the index admission that were predictive of readmission within 30 days.Results9% of CYP were readmitted within 30 days. Half of the 30-day readmissions and 40% of the recurrent admissions between 30 days and 2 years had the same primary diagnosis group as the original admission. These proportions were consistent across age, sex and diagnostic groups, except for infants and young women with pregnancy-related problems (15–24 years) who were more likely to be readmitted for the same primary diagnostic group. CYP with underlying chronic conditions were readmitted within 30 days twice as often (OR: 1.93, 95% CI 1.89 to 1.99) compared with CYP without chronic conditions.ConclusionsFinancial penalties for readmission are expected to incentivise more effective care of the original problem, thereby avoiding readmission. Our findings, that half of children come back with different problems, do not support this presumption.

The majority of fuqoha 'has defined fiqh as a result of understanding, tashawwur and critical reasoning (al-idrak) of a mujtahid. But on the other hand, fiqh as a result of ijtihad teryata is often described as divine law (sharia). As Ijma '(consensus), there are many differences in defining it, but until now there are still many fuqoha' who regard ijma 'as qath'i propositions which are level with texts and are sariari-made propositions' and even claim that those who oppose ijma 'including infidels. Humans often traditionalize actions that are considered good and are their daily needs, so that Islam also still recognizes and contributes to maintaining the tradition (‘Urf) into a method of observation, not only maintaining it but because it pays more attention to the benefit of the people. Because Islam comes in the context of regulating the social order that is oriented towards achieving benefit and avoiding loss (madlarat), moreover the texts of the Shari'a itself do not provide a detailed solution to the diversity of problems of each community. Traditionally the implications of Urf are very limited to only space and time, while legal decisions continue to apply even in different situations and conditions. So the view of jurisprudence towards the world (jurist's worldview) is intended as the development of the Urf concept in order to achieve the universality of maqashid al-sharia.

Persistently active neurons during mnemonic periods have been regarded as the mechanism underlying working memory maintenance. Alternatively, neuronal networks could instead store memories in fast synaptic changes, thus avoiding the biological cost of maintaining an active code through persistent neuronal firing. Such “activity-silent” codes have been proposed for specific conditions in which memories are maintained in a nonprioritized state, as for unattended but still relevant short-term memories. A hallmark of this “activity-silent” code is that these memories can be reactivated from silent, synaptic traces. Evidence for “activity-silent” working memory storage has come from human electroencephalography (EEG), in particular from the emergence of decodability (EEG reactivations) induced by visual impulses (termed pinging) during otherwise “silent” periods. Here, we reanalyze EEG data from such pinging studies. We find that the originally reported absence of memory decoding reflects weak statistical power, as decoding is possible based on more powered analyses or reanalysis using alpha power instead of raw voltage. This reveals that visual pinging EEG “reactivations” occur in the presence of an electrically active, not silent, code for unattended memories in these data. This crucial change in the evidence provided by this dataset prompts a reinterpretation of the mechanisms of EEG reactivations. We provide 2 possible explanations backed by computational models, and we discuss the relationship with TMS-induced EEG reactivations.

Purpose The purpose of this paper is to explore primary care psychological therapists’ experiences of working with mid-life and older women presenting with intimate partner violence (IPV) and develop a theoretical framework using a grounded theory approach to identify the experiences of those practitioners working with this phenomenon. Design/methodology/approach Interviews with 17 practitioners were conducted. The data analysis was informed by a grounded theory approach, which requires three states of data coding: open, axial and selective. Data codes were thematically sorted into causal, contextual, strategic, intervening, interactional and consequential conditions. Findings A core state of therapist helplessness was uncovered. The framework demonstrates that psychological therapists can doubt their ability to work meaningfully with women over 45 years of age experiencing IPV. To avoid the core state of helplessness, therapists use strategies such as avoiding asking questions about partner violence, making assumptions of how patients interpret their own experiences, addressing symptoms rather than the root cause and going above and beyond in attempts to rescue patients. The consequence of therapists’ helplessness often results in burnout. Research limitations/implications The framework identifies barriers in working effectively with IPV and women in the mid-to older-aged populations. Originality/value This study is the first to suggest a framework that is grounded in practitioner experience with capability to transfer to a range of professionals working with mid-to older-aged women such as forensic, medical and specialist psychologists.

Ribonucleotide reductase (RNR) is the only enzyme specifically required for the synthesis of deoxyribonucleotides (dNTPs). Surprisingly, Escherichia coli cells carrying the nrdA101 allele, which codes for a thermosensitive RNR101, are able to replicate entire chromosomes at 42 °C under RNA or protein synthesis inhibition. Here we show that the RNR101 protein is unstable at 42 °C and that its degradation under restrictive conditions is prevented by the presence of rifampicin. Nevertheless, the mere stability of the RNR protein at 42 °C cannot explain the completion of chromosomal DNA replication in the nrdA101 mutant. We found that inactivation of the DnaA protein by using several dnaAts alleles allows complete chromosome replication in the absence of rifampicin and suppresses the nucleoid segregation and cell division defects observed in the nrdA101 mutant at 42 °C. As both inactivation of the DnaA protein and inhibition of RNA synthesis block the occurrence of new DNA initiations, the consequent decrease in the number of forks per chromosome could be related to those effects. In support of this notion, we found that avoiding multifork replication rounds by the presence of moderate extra copies of datA sequence increases the relative amount of DNA synthesis of the nrdA101 mutant at 42 °C. We propose that a lower replication fork density results in an improvement of the progression of DNA replication, allowing replication of the entire chromosome at the restrictive temperature. The mechanism related to this effect is also discussed.

The significance of the regional disproportions at the territory of Serbia, when it comes to demographic resources, imposes in front of the social community a task for public policy measures to be more efficient and more precisely addressed towards the local communities where the limit of their possible acting has not been perturbated yet. Thus, defining of coherent public policies requires good research of the demographic processes and problems on all levels and defining developmental solutions in accordance with them. Dimensioning of demographic potentials is one of the challenges and priorities of spatial planning as well, as a controlling instrument that has been gaining significance in modern conditions. Foreign experience in this field, i.e. the system of spatial planning in European countries, with the special attention paid to the ways of solving problems connected to demographic processes and appearances, is undoubtedly instructive for the domestic practice and the establishment of public policies on state and lower regional levels. Given the fact that the inequality in development is caused, above all, by the expressive metroplization and polarization of the Serbian territory, in modern conditions it is considered that the application of the polycentric development model could help avoiding further excessive economic and demographic concentration. It includes economic competitiveness and social equality (sustainable development) as pre-requisites for the diminishing of local disparities to the acceptable minimum. In that sense, it is considered that a group of middle sized towns represents a pivot in establishing homogeneous national urban system which would lead to the increase in the degree of settlement network consistency. It is necessary that the endeavour to decentralize Serbia be elaborated with concrete measures and instruments that would route further state development, meaning affirmation of the middle sized towns.

Metal sulphides are highly important for the technology of semiconductor film materials. The potential of these compounds has not been exhausted yet when it comes to creating optoelectronic devices, solar cells, and luminescent devices based on them. The goal of this work was to determine the nature of interaction of sulphides in polycrystalline layers of CdS–MemSn, where Me are metals of groups I–VII of the periodic table. Cadmium sulphide was chosen as the common component of all studied systems due to the great photoelectric and luminescent properties of this well-studied material.It was shown that using aerosol spray pyrolysis of the solutions of thiourea complexes, we can obtain solid solutions and chemical compounds of CdS–MеmSn at temperatures not exceeding 500 °C. The main electric, optical, and luminescent properties of the layers were described.It was established that the use of aerosol spray pyrolysis of the solutions of thiourea coordination compounds allows significantly expanding the areas of solubility during the formation of solid sulphide solutions. The specific character of solid-phase interaction and nonequilibrium of the processes occurring during the deposition of layers allow avoiding structural incompatibility of the components expressed in the form of typical factors, such as the non-uniformity of crystal structure, differences in the chemical nature of the components, and discrepancies in sizes of substituting/penetrating atoms.Under such conditions of deposition of films (the lower threshold of deposition temperatures is determined by the temperature of decomposition of the most thermally stable thiourea coordination compound and does not exceed 250 °С), the solid-phase interactions of most sulphides cannot be achieved. Therefore, the interaction occurs at the moment of thermal destruction of complex compounds due to the emerging valence opportunities of their structural fragments

Lightweight constructions represent an economical alternative to traditional buildings, one of whose main drawbacks is the very high energy load needed to keep internal comfort conditions, as they are unable to curb rapid variations of temperature. When compared to heavier weight materials buildings, it is estimated that to maintain a thermally comfortable temperature range of 18-24?C, low weight materials use between 2 and 3 times the heating and cooling energy needed by a heavy weight material construction. The research concept is based upon the fact that outdoor/indoor heat exchanges (which play a significant part of lightweight buildings cooling and heating loads) can be potentially controlled by a new fiber insulation that possesses a thermally active heat storage capacity. During the day, when temperature rises, the peak loads can be largely absorbed by a PCM (Phase Change Material) - enhanced fiber insulation layer, only to be slowly discharged back to the environment later (during the night time, when outside temperature drops), without affecting the interior building energy balance, as it is aided by the presence of an standard low heat transfer fiber insulation layer. This approach will provide a much slower response of the building envelope to daily temperature fluctuations, helping in maintaining inside temperature in a comfortable range and thus avoiding the need for extra energy consumptions to accomplish it. Effective levels of indoor comfort will be also guaranteed by the well known fiber materials excellence, when it comes to reduce airborne noise transmission and its superior performance upon controlling the sound resonance in construction cavities. Development of such material is in final phase in frame of European FP7 project STOREPET (FP7-SME-2011-2, Proposal 286730). Project participant from SEE is Construction Cluster ?Dundjer? from Nis. Development and application of project results will be presented in this paper.

The COVID-19 pandemic has caused many negative socio-economic consequences for seafarers and shipowners of such importance that, on the one hand, it inspired and, on the other hand, it became an impulse to undertake research in this direction. It seems that avoiding at least some consequences would be possible if both shipowners and ship masters operated based on safety management procedures strictly adapted to the pandemic situation. Of course, many crisis management procedures have been developed in maritime practice so far. Still, they mainly relate to such events as maritime incidents, maritime accidents, maritime disasters, oil spills, terrorist attacks, or sea piracy. However, they do not consider the specificity of a crisis situation created for the safety of the ship’s crew by the global pandemic. Its appearance made all maritime transport entities, especially shipowners, aware of the lack of preparation for such an eventuality. Based on the general recommendations of international organizations, such as the WHO (World Health Organization) or the IMO (International Maritime Organization), they began developing and implementing urgent procedures for handling ships under COVID-19 conditions. Since the recommendations were formulated generally and the pandemic spread very quickly, the prevention and response procedures for a ship found to be affected by COVID-19 were developed ad hoc and, therefore, were often flawed. Consequently, it was concluded that it is worth creating a universal model of the procedure for dealing with a sea-going ship in pandemic conditions and reducing the adverse socio-economic consequences for shipowners and seafarers. This became the primary goal of the research undertaken in this direction, and this goal was closely related to the adopted central research hypothesis. The substance of the matter comes down to the fact that knowledge of the factors causing coronavirus infections will allow the development and implementation of effective procedures for handling ships in pandemic conditions. It will also reduce the risk and consequences of coronavirus infections. COVID-19 infections can be caused by many factors that are beyond the control of the shipowner and the ship’s captain. Still, there are also those factors that they can control and thus eliminate or at least reduce the risk of contracting the coronavirus by the crew. Thus, their correct identification, ranking their importance in terms of the risk of infection, and then focusing on the elimination of the most important of them is the basis for building a universal model, in the sense of the possibility of applying to any sea-going ship in pandemic conditions. The work includes RCA (Root Cause Analysis), stratification analysis, weighted Ishikawa diagram, and Lorenz-Pareto chart. The primary sources of information used in the research came from the literature review, the analysis of normative acts, the analysis of documentation and procedures on board ships in pandemic conditions, questionnaire research, direct and focus interviews, and participant observation.

Abstract. In recent years there has been a great effort by the agents of the AECO sector aimed at an efficient use of data interoperability between the participating disciplines and the applicability in the specific software. In this context, the BIM (Building Information Modeling) methodology, moves in a collaborative data management environment to monitor and control the design, planning, cost control, construction processes. and building maintenance. But to enjoy the benefits of BIM in its fifth dimension (5D), cost and time savings, it is essential to properly plan each phase of the project and manage the information effectively within the same team.Therefore, this research aims to validate an effective method for the creation of the information of a constructive entity using codes, disaggregated by budget line items, necessary for the mapping of data in the structure of the IFC file (Industry Foundation Classes) and the confrontation with the filtering rules in quantification programs, in 1 to 1 relationship. Under normal conditions, the item to be measured would have a quality or parameter that distinguishes it from another item. All elements are mapped following an IFC structure using the eCOB standard. This information will be collected in the quantification program to compare it with the information established in the rule corresponding to each item.The analyzed and tested method, based on a proper structuring and classification of data of the elements that make up the BIM model, has been productive and efficient in avoiding random decision-making by the operator who analyzes the quantifications and that may lead to errors or inaccuracies when applying the metric. The result of the study shows that the combinations of parameters, influences by the possible variables of the constructive element, can be considerably reduced. The percentage of rules would decrease by a ratio of 17/120 in the IFC information mapping process to be validated in quantification and valuation software, improving data exchange and interoperability in an international environment.

The purpose of the article is to implement a systematic analysis of the factors of the formation of a stable system of political governance. To clarify the functions and structure of a stable political system, the characteristics of stability are highlighted, according to which the political system: has signs of legitimacy; is able to cope with the threat of illegitimate violence; supports the constitu-tional system; reproduces a model of behavior based on stability. Methodologically, the article is based on the works of classical and modern scientists (P. M. Khomyakov, M.A. Gaydes, I.B . Rodionov, A. A. Khomiakov). Makarycheva), devoted to the systematic analysis of political systems. The paper also uses morphological analysis, analysis of political efficiency, and in the final part — the method of state-management design. The author comes to the conclusion that the functions and structure of the modern political system should be considered from the point of view of the defini-tions of “political stability”, viewed through the prism of the absence of political threats, adaptive irremovability of political subjects and the balance of political forces. Political stability implies that the distribution of resources in society involves not only the institutional subsystem of the political system, but also the functional, regulatory and ideological subsystems. Morphological analysis demonstrates that a stable political system is characterized by a balanced interaction of subsystems, in which at least the institutional, regulatory and functional subsystems jointly determine the process of functioning and development of the political system. Stability is the basis and guarantee of po-litical development in the modern world, and stability is not contrary to innovative development or development in general. Both stability and development are the basic conditions for the development of a modern political system, methods of avoiding negative adaptation in the global environment. Stability is not synonymous with closeness — on the contrary, it implies horizontal and vertical mobility, a constitutional system, and a focus on maintaining the activity of political actors. At the same time, all these processes cannot be allowed to take their course and develop outside the political control of the vertical structures of power. Integrity as a system-wide property is an integral basis for the stability of the political system.

В статье представлена характеристика осужденных - жертв неправомерного применения физической силы и (или) специальных средств, включающая в себя основные уголовно-правовые и уголовно-исполнительные признаки данных осужденных, учитывание которых может оказать научно-методическую помощь в выработке оптимальных мер по профилактике подобного применения. Автор приходит к выводу, что эти осужденные характеризовались за время отбывания наказания в целом отрицательно. Ими являются мужчины зрелого возраста, с низким уровнем образования, повторно осужденные за преступления против собственности, жизни и здоровья, в сфере незаконного оборота оружия и наркотических средств, частично признавшие вину в совершенном преступлении, содержащиеся в исправительных колониях строгого режима, для лиц, ранее отбывавших лишение свободы, негативно относящиеся к порядку и условиям отбывания наказания, в связи с чем поставленные на профилактический учет по основаниям, связанным с проявлениями отрицательной реакции на установленные режимные требования, избегающие выполнять возложенные на них в процессе отбывания наказания обязанности, не стремящиеся к исправлению, положительно относящиеся к проявлениям криминальной субкультуры, поддерживающие и пропагандирующие ее среди осужденных. Для обеспечения эффективности воспитательной работы с ними необходимы методы принуждения. Эти осужденные отличаются весьма негативными психологическими характеристиками. The article describes the characteristics of convicts - victims of the unlawful use of physical force and (or) special means, including the main criminal law and criminal executive signs of data of convicted persons, taking into account which can provide scientific and methodological assistance in developing optimal measures to prevent such use. The author comes to the conclusion that these convicts were characterized during the period of serving the sentence as a whole negatively. They are men of mature age, with a low level of education, re-convicted of crimes against property, life and health, in the sphere of illicit trafficking in weapons and narcotic drugs, who partially pleaded guilty of the crime committed, in the correctional colonies of strict regime for those who have previously served imprisonment, negatively related to the order and conditions of serving the sentence, in connection with which they are put on a preventive record on the grounds related to manifestations of a negative reaction to tanovlenii security requirements, avoiding to carry out their process of serving the sentence duties without seeking to correct positively related to the manifestations of the criminal subculture, supports and promotes it among the convicts. To ensure the effectiveness of educational work with them, coercive methods are necessary. These convicts are distinguished by very negative psychological characteristics.

Abstract Research purpose. Modern work is increasingly taking place in temporary workgroups embedded in decentralized work environments that transcend organizational boundaries. The first implementations of the shared workspace idea emerged in the 1990s in the CSCW research area and are now firmly integrated into the working world with systems such as Google Drive, OneDrive or Dropbox. However, when it comes to accessing documents, problems arise in terms of coordinating access to documents. Who can access the documents, modify them, and upload them back to the shared workspace? It should be noted that concurrent changes can lead to inconsistencies. Furthermore, incorrect changes to the content of documents can have economic and legal consequences. Who is responsible for this? Strict access control can avoid this problem if necessary. However, it contradicts the approach of agile cooperation, which benefits, among other things, from access to documents that is not restricted in terms of time and place. Design / Methodology / Approach. The article proposes a semantic approach for access coordination of shared workspaces. Its basis is the legal distinction between the levels of legal control (owner) and material control (possessor). The owner of an object has the right and the duty to allow the other participants of the shared workspace to access it, i.e., to have material control. This is done through an agreement between the owner and the possessor, which specifies the conditions of material control. In addition to coordinating access, the owner is also responsible for arbitrating in case of conflict and deciding which changes are valid and which are not. Findings. Transferring the distinction between owner and possessor leads to three possible classes of conflicts: Ownership vs ownership, ownership vs possession, and possession vs possession. Conflict schemes within these classes of conflict are analyzed in detail. On the one hand, it is possible to use strict, conflict-avoiding settings, but this tends to limit cooperation. On the other hand, greater cooperation agility can be enabled if the owner situationally controls access or if the owner has preset flexible response tactics in case a conflict arises. A closer look at possible conflict classes shows that it is necessary to adapt the legal concepts of owner and possessor to the cooperation situation. Originality / Value / Practical implications. The concept of the legal distinction between owner and possessor has not yet been applied to the domain of access coordination in shared workspaces. This approach can introduce the previously missing semantics for access coordination, at least on an informal basis. It also improves participants’ awareness of the context of cooperation.

Under the conditions of society's movement towards a civil war at the end of 1917 - the first half of 1918, the images of “Others” (allies or opponents) acted as meaningful elements of the constructed identities of its potential participants and influenced the ideas they put forward. An analysis of the formation of the image of the UK, France, Japan and the USA in the non-Soviet periodical press of the East of Russia in the period from the end of 1917 to the summer of 1918 reveals the peculiarities of the foreign policy context's influence on public sentiment and the content of propaganda discourses of political opponents of the Bolsheviks. The aim of this work is to determine the content of the image of the Allies, constructed in the periodical press of the East of Russia, and to identify its influence on the ideological aspect of the formation of the anti-Bolshevik movement at this stage. The main source for the study were non-Soviet newspapers and magazines - party, cooperative and private publications published in the Urals, Siberia and the Far East in the period from November 1917 until August 1918. The author comes to the conclusion that the image of the Entente countries and the United States, which was formed in the non-Bolshevik periodical press of the East of Russia at that time, was distinguished by the duality of content. The change in value judgments, which were elements of this image, depended on a number of factors - the incoming information about the policies of the allied countries and the course of the World War, the perception of the external and internal political actions of the Bolsheviks, the peculiarities of the functioning of the information field itself. According to socialists (Social Democrats and SocialistRevolutionaries), the “imperialistic” Entente and the United States were no longer allies and helpers of Russia, which was sometimes expressed in the using of the term “former allies”. The analysis of the vicissitudes of international relations from the point of view of the class approach seriously forced the Siberian “revolutionary democracy” to fear an invasion from the East, which undoubtedly promoted to the formation of an opinion about the allies as a threat in the relevant publications. Liberals, in particular, the publications of constructive democrats, did not agree with their opponents from the left and viewed allies more as a potential helper, although they expressed concerns about the consequences of a possible intervention. At the same time, the key value-based attitude of the anti-Bolshevik forces was also being formed - the necessity of rallying society and creating a firm government capable of starting the revival of the country. Both socialists and liberals persistently sought to root in the minds of readers the idea that the unity of the whole society around the Constituent Assembly would create a new government - more effective than the Soviet one, thereby ensuring peace and avoiding the intervention of the Entente and the United States.

Purpose In mature industries, downward vertical (line) extension has become an increasingly popular strategy, particularly for automobile manufacturers aiming at expanding their consumer bases and/or avoiding competition in higher market segment. This paper aims to examine how Mercedes-Benz (MB) practiced a downward vertical line extension within the same product category. When commercialized as a product line innovation, the MB A-Class was the first and most symbolic move made by a premium brand in the automobile industry. Design/methodology/approach This paper investigates the microfoundations of a vertical downward extension strategy. To do so, the authors adopt a narrative style to analyze the story of the MB A-Class from its inception to its commercialization. Secondary data sources, such as company websites, annual reports, internal documents, books, public relations and press releases, were used. Qualitative as well as quantitative performance outcomes were assessed using market and product sales in Western Europe (1997-2016) and the results of an MB brand image survey conducted in 1998 following the accident faced by the A-Class. Findings The case illustrates that contrary to initial assumptions, lower-quality extensions may be relevant for prestige brands under certain conditions and identifies four strategy components that may drive a successful downward stretch: combine organizational, product, process and marketing innovation with the support of dynamic capabilities; manage paradoxes/contradictions in terms of product development; target the high-end of a lower consumer segment; and adopt a “brand humility talk scheme”. Research limitations/implications Existing studies primarily focus on consumers’ evaluations of vertical step-down extensions. Rare are the articles that adopt the company’s perspective. Moreover, additional research is needed to assess the short- and long-term impacts of vertical downward extension on performance outcomes. Practical implications The case of the MB A-Class encourages top executives to consider the trade-offs inherent to a down-market strategic move: keeping the (premium) brand’s standards high within a reduced cost/price envelope while learning the codes of the new/bottom of the market. In addition, the A-Class may serve as a fundamental school case for marketing managers and creative advertising agencies on what should and should not be done, whether at the product or at the advertising level. Originality/value This paper demonstrates that a premium brand that practiced a vertical downward line extension can expand its sales in a mass market, by targeting a small but growing segment with a high willingness to pay for more expensive products. This adds to the contention that it is not the downscale extension product price per se that negatively affects the parent brand but rather where it stands in the hierarchy of the market segment considered and the ability of the premium brand to integrate the downscale extension to its own history (i.e. combining its original values with tangible product benefits while backing the cause of the new market). Finally, the story of the A-Class strongly suggests that any company needs to upgrade its capabilities as part of the learning process of a new market to convert a business opportunity into a market success.

SiN film has been one of essential materials for electronic devices for its high dielectric properties as well as both chemical and thermal stabilities. However, it is found that SiN film made by LPCVD(Low Pressure Chemical Vapor Deposition) in certain process conditions has the weakness of dielectric voltage durability, which leads to the charge breakdown(Qbd) in application uses. The occurrence frequency of this Qbd strongly depends on the temperature of N2 anneal which is processed after deposition[Ref.1]. However, the details of the breakdown mechanism have not been cleared. In this study, in order to find the key defect which mainly causes the Qbd, we perform ESR measurements for the SiN samples annealed at several temperatures of 700 – 1150 degree C, and also measure FTIR(Fourier Transform Infrared) spectrum for SiN samples, in order to estimate the N2 anneal effect on the change of crystal bonds. SiN samples were made by LPCVD using a mixture gas of SiH2Cl2 and NH4 on the Si(0 0 1) substrate at the temperature of 700 degree C. Standard SiN layer thickness were designed to be 54 nm for checking the N2 anneal temperature dependency, and some other samples were grown to have thicker SiN layer of 100 nm and 150 nm for checking the SiN layer thickness dependency. After SiN deposition, the annealing process with N2 atmosphere has been done at 700 – 1150 degree C. We also prepared a non-annealed sample for comparison. ESR spectrum of each SiN samples have been obtained using JEOL JES-RE2X spectrometer at room temperature with the microwave of 9.4 GHz, 0.4 mW. To get statistically sufficient signals, we accumulated approximately 300 times of field scan in the range of ± 7.5 mT at the center field of 335 – 337 mT. We performed fitting analyses for obtained spectrum using 14 peaks with differential shape of Gaussian for background, and Lorentzian for other signals. Fig.1 shows the ESR spectra after UV irradiation and the fitted curves for SiN sample annealed at 900 degree C. We found K center, which is from SiN layer, E’ center, which is from oxide layer between SiN layer and Si substrate, and Pb center, which is from upper a few atomic layers of Si substrate, and we also found the unknown signal, named M signal, having unignorable amount of peak at the g-value of 2.0037, which locates between Pb and E’ center. We expect this unknown signal to be attributed to the dangling bond of Si partially oxidized. We can infer that the breakdown starts with Pb center and M signal at 900C and increases with increasing temperature observed as E’ center. We also measured ESR signal peaks for samples with different SiN layer thickness and found the intensities of Pb center and M signal changes irrelevant to SiN layer thickness while the K center increase linearly as the function of SiN thickness. This confirms us that the M signal comes from interface region just above and/or near Si substrate, not from the inside of SiN film. We measured FTIR spectrum for SiN samples at room temperature by means of transmission mode using Fisher Scientific NICOLET8700. Each FTIR measurement has done after N2 purging for 1 – 2 hours avoiding air contamination. The close-up of Si-H stretching signal in FTIR spectrum is shown in Fig.2. With increasing N2 anneal temperature, Si-H intensity decreases, and at 1150 C, splits into two peaks, which means that partially oxidized back-bond state, H-Si(-O,H), disappeared and became the two states of H-Si(-O), and H-Si(-H). This change corresponds to the decrease of M signal intensity at high N2 anneal temperature observed in ESR measurements. [Ref.1] “Effect of N2-Anneal Temperature on Silicon Nitride Film: (I) Time-Dependent Dielectric Breakdown and ESR Evaluations” (Consolidated presentation in this conference) Figure 1

Genotoxic Effects of Radiofrequency-Electromagnetic Fields. IntroductionRadiation is energy emission in the form of electromagnetic waves emitted from the solar system and natural resources on earth. The currents produced by the elementary particles formed by the electric current create the magnetic field. Earth's surface is under the influence of the geomagnetic field emanating from the sun. However, the outer liquid also has a magnetic field created as a result of heat transfer in the core. Therefore, all living organisms on earth live under the influence of electromagnetic fields (EMF). Today, besides these natural energy resources, rapidly developing technological developments provide most of the convenience in our lives and expose people to artificial electromagnetic fields. However, man's magnetic field is also under the influence of other natural and artificial magnetic fields around him. In particular, by ionizing radiation, which carries enough energy to break down the genetic material, die cells as a result of DNA damaging, and other diseases, especially cancer, can develop as a result of tissue damage. Electromagnetic Fields in Our LivesToday, apart from natural geomagnetic fields, radiation is emitted from many technological devices. The spectrum of these fields includes many different types of radiation, from subatomic radiation such as gamma and X-rays to radio waves, depending on their wavelengths. Though, as a result of the rapid increase of technological growth, the duration and amount of exposure to EMF is also steadily increasing. On the other hand, wireless gadgets such as computers, smartphones and medical radiological devices have become a necessity for humans. Almost everyone is exposed to radiofrequency electromagnetic fields (RF-EMF) from cell phone and base station antennas or other sources. Thus, the damage caused by the radiation to the environment affects living organisms even many kilometres away unlimitedly. All organisms in the world live under the influence of these negative environmental changes and a large part of the world population is exposed to radiofrequency (RF) radiation for a long time in their daily lives. So, though we are not aware of it, our organs and tissues are constantly exposed to radiation. Therefore, radiation adversely affects human, animal and plant health and disrupts the environment and ecological balance. An example of negative effects, radiation can cause genetic changes in the body (Figure 1). Radiation is divided into ionizing and non-ionizing. Ionizing radiations cause electron loss or gain in an atom or group of atoms in the medium they pass through. Thus, positively or negatively charged ions are formed. High energy X, gamma, ultraviolet and some visible rays in the ionized region of the electromagnetic spectrum can be counted. Since gamma rays, X rays and ultraviolet rays can ionize the molecules in living things more, they can easily disrupt the chemical structure of tissues, cells and DNA molecules in living organisms. Therefore, they can be very dangerous and deadly to living things. The energy of the waves in the non-ionizing region of the electromagnetic spectrum is low and the energy levels are insufficient for the ionization of molecules. Electricity, radio and TV waves, microwaves, and infrared rays are not ionizing because they have low energy. Waves emitted from electronic devices (cell phones, computers, microwave ovens, etc.) are absorbed by the human and animal body. The amount of energy absorbed by the unit biological tissue mass per unit time is called the specific absorption rate (SAR), and its unit is W/kg. Risks of Electromagnetic Fields on Living ThingsDepending on the structure of the tissues and organs, the radiation must reach a certain threshold dose for the effect to occur. Radiation levels below the threshold dose are not effective. Depending on the structure of the tissues and organs, the radiation must reach a certain threshold dose. The effects of small doses of waves are negligible. However, the clinical effects of waves above a certain threshold may increase. High dose waves can cause cell death in tissues. Damages in the cell may increase the risk of cancer and hereditary damage after a while, and somatic effects in people exposed to radiation may cause cancer to appear years later. There is much research on the effects of RF fields. In vitro and in vivo studies on rats, plants and different tissues of humans; suggests that the RF fields are not genotoxic and the fact that harmful effect is due to the heat effect. The contradictory results on this issue have brought about discussions. Therefore, there are still concerns about the potential adverse effects of RFR on human health. A good understanding of the biological effects of RF radiation will protect against potential damages. Due to these uncertainties, with the electromagnetic field project of the World Health Organization, experimental and modelling studies on the biological effects of RF radiation have been accelerated. In 2011, the International Agency for Research on Cancer decided that RF-EMR waves could be potentially carcinogenic to humans (2). Considering that almost everyone, including young children, uses mobile phones in addition to other technological devices, the danger of electromagnetic waves has increased social interest. Genotoxic Effects of EMFIn addition to stimulating apoptosis and changes in ion channels, RF-EMF waves also have a potential effect on genetic material. The radiation absorbed by organisms causes the ionization of target molecules. In particular, biological damage may occur as a result of stimulation/ionization of atoms and disruption of molecular structures while ionizing radiation passes through tissue. As a result of ionization in the cell, electron increases and free electrons cause damage, especially in macromolecules and DNA. Free electrons move directly or indirectly. Free electrons directly affect the phosphodiester or H-bonds of DNA. As a result, the phosphodiester bonds of DNA in the cell are broken, single or double-stranded breakages and chemical toxins increase. DNA double-strand breaks are the most relevant biologic damage induced by ionizing radiation (3,4). There are no cells that are resistant to radiation. The nucleus of the cell and especially the chromosomes in dividing cells are very sensitive to radiation. One of the most important effects of radiation on the cell is to suppress cell growth. In particular, growth is impaired in cells exposed to radiation during cell division (mitosis). Consequently, cells with a high division rate are more sensitive to radiation. DNA damage in somatic cells can lead to cancer development or cell death. Cell death can occur as a result of breaking down DNA because ionizing radiation has enough energy to break down the cell's genetic material. Thus, tissues are damaged and cancer development may be triggered. DNA damage caused by radiation in cells is repaired by metabolic repair processes. If the breaks in DNA as a result of DNA damage caused by radiation in cells are not too large, they can be repaired by metabolic repair processes. Still, errors may occur during this repair. Chromosomes containing different genetic codes and information may also occur. In the cell, the released electrons interact with water molecules, indirectly causing the water to be reactively divided into two parts. Free radicals carry an electron that is not electrically shared in their orbits. Free radicals can cause genetic damage in DNA such as nucleotide changes, double and single-strand breaks. Radiation can cause chromosomes to break, stick together and rearrange. All these changes can lead to mutations or even further, the death of the cell. However, in addition to ionizing radiation, extracellular genotoxic chemicals and intracellular oxidative metabolic residues can also create stress in cells during DNA replication and cell division. Damage may occur during DNA replication under such environmental stress conditions. To date, conflicting results have been reported regarding the genotoxic effects of RF-EMF waves on genetic material. It has been reported that the energy of low EM fields is not sufficient to break the chemical bonds of DNA, but the increase in exposure time is effective on the formation of oxygen radicals and the disruptions in the DNA repair process. The absorption of microwaves can cause significant local warming in cells. For example, an increase in temperature has been observed in cells in culture media exposed to waves of high SAR levels. However, there is evidence that reactive oxygen species are formed in cells indirectly and experimentally exposed to RF-EMF waves. Free oxygen radicals can create nucleotide entries in DNA as well as bind cellular components to DNA bases (5). The frequency of polymorphisms observed in DNA repair mechanism genes in children with acute leukaemia living close to high energy lines reveals the effect of this energy on the repair process. Significant evidence has been reported that genotoxic effects occur in various cell types when exposed to RF-EMF waves (6-10). Here, it has been reported that cells exposed to RF-EMF waves (1.800 MHz, SAR 2 W/kg) cause oxidative damage in mitochondrial DNA, DNA breaks in neurons and DNA breaks in amniotic cells (6,10). Similarly, the damage has been reported in lymphocytes exposed to various RF-EMF waves (8). However, exposure to RF-EMF waves is known to cause chromosome imbalance, changes in gene expression, and gene mutations. Such deleterious genetic effects have also been reported in neurons, blood lymphocytes, sperm, red blood cells, epithelial cells, hematopoietic tissue, lung cells, and bone marrow (1,11,12). It has been found that exposure to RF-EMF radiation also increases chromosome numerical aberrations (6,13). It has also been reported that increased chromosome separation in mouse oocytes exposed to EM and increased DNA fragmentation and apoptosis in fly egg cells (14,15). However, increased DNA breaks have been reported in the blastomeres of embryos of pregnant mice exposed to a frequency of 50 Hz, and a decrease in the number of blastocysts has been reported (16). Genetic damages to sex cells can lead to persistent genetic diseases in subsequent generations. Today, X-ray devices used for medical diagnosis have become one of the largest sources of radiation. These radiological procedures used for diagnosis constitute an important part of ionizing radiation. During these processes, the human body is visibly or invisibly affected by X-rays. As a matter of fact, X-rays have effects of disrupting the structure and biochemical activities of DNA, RNA, proteins and enzymes that are vital in the organism (17). Many studies on this subject have revealed that radiation has suppressive and mutational effects on DNA synthesis. These effects can cause serious damage to the cell as well as DNA and chromosome damage. In a recent study, chromosome damage was investigated in patients with X-ray angiography and personnel working in radiological procedures (18). Our findings showed that the beams used in interventional radiological procedures caused chromosomal damage and the rate of chromosomal abnormalities (CAs) increased significantly in patients after the procedure and this damage increased with the amount of radiation dose. Therefore, the radiation dose to be given to the patient should be chosen carefully. Besides, our findings showed that the frequency of CA is significantly higher in personnel working in radiological procedures. This reveals that interventional cardiologists are exposed to high radiation exposure. For this reason, we can say that the personnel working in radiological procedures (physician, health technician and nurse) are very likely to get diseases after years because they are exposed to low doses but long-term X-rays. Therefore, both the potential risks and safety of exposure to medical radiological devices must be continuously monitored. Furthermore, the fact that chromatid and chromosome breaks are very common among structural CAs in our findings suggests that they may be the cause of malignancy. Because, there are many cancer genes, tumour suppressor genes, enzyme genes involved in DNA repair and important genes or candidate genes responsible forapoptosis on these chromosomes. All this information shows that patients are more susceptible to DNA damage and inappropriate radiological examinations should be avoided. Therefore, X-ray and other diagnostic imaging techniques should not be applied unless necessary, and physicians and patients should be more careful in this regard. It has been reported that RF-EMR waves emitted from wireless communication device mobile phones have a genotoxic effect on human and mammalian cells (6,19). In a recent study; The effects of 900 and 1800 MHz cell phone frequencies on human chromosomes were investigated in amniotic cell cultures (6). Here, it has been reported that chromosome packing delays, damage and breaks occur in amniotic cells exposed to 900 and 1800 MHz every day at 3, 6 and 12 hours for twelve days. However, it was found that the frequency of 1800 MHz caused more CAs than 900 MHz, and the amount of damage increased with increasing usage time. These results confirm that GSM-like RF-EMR causes direct genotoxic effects in human in vitro cultures and has adverse effects on human chromosomes, and these effects increase in parallel with exposure time. This shows us that the mobile phone carries a risk for human health and these genetic damages can cause cancer. Therefore, necessary precautions should be taken for these harmful effects of mobile phones. Among these measures, the periods of mobile phone use should be kept short, especially the exposure of developing children and infants to mobile phones should be prevented, and avoiding excessive use of mobile phones may be one of the precautions against cancer. However, in order to evaluate it in more detail, the effects of mobile phones with environmental mutagens and/or carcinogens should be considered in subsequent researches. ConclusionToday, in parallel with the increasing technological developments, the demand of the society for electronic devices and phones and the frequency ranges of electronic devices are constantly increasing. Waves emitted from electronic devices are absorbed by human and animal bodies. Especially, the use of phones by contact with our body and the increase in usage time affects not only adults but also young children. Therefore, there is increasing concern in society about the negative biological effects of EM waves emitted from phones and other electronic devices. Results from all studies show that RF-EMF waves may be carcinogenic due to their genotoxic effect. Because cancer is a disease that occurs as a result of genetic damage. Considering these negative and harmful effects, regulations following international standards regarding the use of electronic devices should be made and society should be made aware of the risks.References Kim JH.; Lee K.; Kim HG.; Kim KB.; Kim HR. 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Two-dimensional (random) walks in cones are very natural both in combinatorics and probability theory: they are interesting for themselves and also because they are strongly related to other discrete structures. While walks restricted to the first quadrant have been studied a lot, the case of planar, non-convex cones – equivalent to the three-quarter plane after a linear transform – has been approached only recently. In this article we develop an analytic approach to the case of walks in three quadrants. The advantage of this method is to provide uniform treatment in the study of models corresponding to different step sets. After splitting the three quadrants in two symmetric convex cones, the method is composed of three main steps: write a system of functional equations satisfied by the counting generating function, which may be simplified into one single equation under symmetry conditions; transform the functional equation into a boundary value problem; and finally solve this problem, using a concept of anti-Tutte's invariant. The result is a contour-integral expression for the generating function. Such systems of functional equations also appear in queueing theory with the famous Join-the-Shortest-Queue model, which is still an open problem in the non-symmetric case.

AbstractIn this article we are interested in finding positive discrete harmonic functions with Dirichlet conditions in three quadrants. Whereas planar lattice (random) walks in the quadrant have been well studied, the case of walks avoiding a quadrant has been developed lately. We extend the method in the quarter plane—resolution of a functional equation via boundary value problem using a conformal mapping—to the three-quarter plane applying the strategy of splitting the domain into two symmetric convex cones. We obtain a simple explicit expression for the algebraic generating function of harmonic functions associated to random walks avoiding a quadrant.

Sheet metal forming processes for manufacturing truncated cones can be divided into methods which use shape related tooling to produce the required form, for example, spinning and deep drawing, and processes that utilise kinematics to produce the required geometry, for example, roller, air and swivel bending. Such kinematic forming methods can achieve high degrees of forming flexibility but require process models to avoid elaborate trial and error approaches. For the incremental manufacture of cones, CNC swivel bending as yet lacks such a process model. In addition, with the current ‘state of the art’ processes, the manufactured cones exhibit geometric defects with respect to concentricity and skewing. In this study, the operation of a CNC bending machine fitted with an upper beam that can be inclined was investigated. The proposed inclination of the beam corresponds to the desired conical shape of the product. The machine was provided with a radial sheet feed mechanism (back-gauge) to feed material in even segments between bent corners thus avoiding geometric imperfections. A plasto-mechanic process model was developed to deliver the process parameters for swivel bending of specific conical geometries. The process model was validated by numerical simulations and practical bending experiments. Coarsely segmented conical shapes can be manufactured using the analytically calculated process parameters. For conical geometries, the process modifications of sequential swivel bending showed satisfactory improvements in the initial bending defects, that is, lack of concentricity and skewing. Compared with the target geometries, a tendency towards larger diameters remained in the experiments and is explained by the boundary conditions of the sequential process and if a larger number of bending increments is carried out. The present study delivers a first approach to determine the process parameters for the sequential operation of a swivel bending machine in order to provide relevant process parameters for the industrial production of conical components.

Abstract Background Sports motoring and racing imply high physical and psychological stress, during pre-competition phases and the competition itself. Therefore, there is growing interest of racing teams for new technologies providing real-time monitoring of psychophysiological reactions of pilots to highly-demanding driving and vehicle dynamics, to improve personalized training, while reducing human risks and costs. Professional Driving Simulators (PDS) are ideal to assess in real-time vehicle dynamics under any kind of programmable virtual driving conditions, but a direct connection with the driver's physiology is still limited. A novel wearable system and software have been developed, providing simultaneous assessment of pilot's stress reactions, by real-time calculation and monitoring of time-variant heart rate variability (TV-HRV) spectral parameters (SP) and of skin potential response (SPR), in correlation with vehicle's dynamics. Purpose This study aimed to demonstrate the reliability of the method in detecting the pilot's stress induced by different driving demands. Methods 10 volunteers (age 26±2.3 years) were enrolled to pilot a racing car under realistic conditions simulated by the DIM® PDS (Vi-grade). The study protocol consisted of 5-minutes baseline rest, sitting in the cockpit; 5-minutes driving along a straight highway without obstacles; 6-minutes of medium-stress slalom between cones, avoiding collision; 8-minutes racing 4 laps on a race track, at maximum possible speed, but avoiding crashes. ECG and SPR signals were acquired (1 Khz sample rate), with the Vi-BioBox connected to textile wearable sensors. A proprietary software was developed to analyze and stream the TV-HRV and SPR data in real-time to WINTAX4 data logging software for automotive racing industry. Real-time assessment of the pilot's stress was based on the integration of transient changes of HRV-SP and of the Root Mean Square value of two SPR signals (SPRRMS). To validate the accuracy of the real-time HRV analysis, all data were analyzed also off-line with Kubios Premium 3.4.1. software. Results The Vi-BioBox signals were adequate for real-time calculation and monitoring of transient variations of HRV-SP. A good correlation was found between transient stress-induced increment of pilots' SPRRMS values and the occurrence of driving errors (pink-red spots automatically transferred onto the race track – Figure 1). A good match was found between the real-time HRV values calculated by the VI-BioSoft and their off-line calculation with Kubios (v. 3.4.1 Premium). Two pilots, suffering simulator sickness, had prodromal alteration of cardiac autonomic modulation. Conclusion The integration of a Vi-grade PDS with the novel system for real-time calculation and telemetric monitoring of time-variant HRV and SPRRMS provides immediate information about pilot's autonomic response to driving demands and emotional reaction to vehicle's dysfunction, driving errors and bad performance. Funding Acknowledgement Type of funding sources: None. Figure 1

Now a day’s road accident is one of the principal concerns in our states. Reckless automobile driving and driver drowsiness are the major motives in the back of those road accidents. The alarming rate of accidents and uncontrollable automobiles on the streetdemand an automatic system that could guide drivers right now in dangerous conditions. While any obstacle (just like the human, vehicle, and some other item) comes in front of the vehicle, control speed of the vehicle is the viable strategy to keep away from injuries. While a driver in a drowsy state or sleep state, give warning to the driver and control the velocity of the vehicle is the possible way to keep away from injuries. We endorse a solution in our mission to avoid avenue injuries and to manipulate the rate of automobiles. The machine will locate boundaries and motive force drowsiness using an ultrasonic Sensor and eye blink sensor and Arduino will execute a collision-avoidance gadget according to a pre-burnt code in the Arduino. The machine has also velocity manipulate features. It’s going to reduce or increase the rate of the vehicle relying on the impediment distance from the shifting car to decrease the damage or collision of an accident. Furthermore, if any obstacle from the bottom comes in the direction of cars, right now a buzzer will alert the driving force, and if any quick circuit happens in the engine element smoke sensor detecting and gives alert to the driving force and stop the automobile.

AbstractIn this paper, a construction of $$(n,k,\delta )$$ ( n , k , δ ) LDPC convolutional codes over arbitrary finite fields, which generalizes the work of Robinson and Bernstein and the later work of Tong is provided. The sets of integers forming a (k, w)-(weak) difference triangle set are used as supports of some columns of the sliding parity-check matrix of an $$(n,k,\delta )$$ ( n , k , δ ) convolutional code, where $$n\in {\mathbb {N}}$$ n ∈ N , $$n>k$$ n > k . The parameters of the convolutional code are related to the parameters of the underlying difference triangle set. In particular, a relation between the free distance of the code and w is established as well as a relation between the degree of the code and the scope of the difference triangle set. Moreover, we show that some conditions on the weak difference triangle set ensure that the Tanner graph associated to the sliding parity-check matrix of the convolutional code is free from $$2\ell $$ 2 ℓ -cycles not satisfying the full rank condition over any finite field. Finally, we relax these conditions and provide a lower bound on the field size, depending on the parity of $$\ell $$ ℓ , that is sufficient to still avoid $$2\ell $$ 2 ℓ -cycles. This is important for improving the performance of a code and avoiding the presence of low-weight codewords and absorbing sets.

The architecture design today has new expressive features due to the parametric and computational modelling software, which greatly amplify the potential of language. This condition makes it possible to generate customised elements and systems through a process of cyber-physical interaction between design and architectural production. As well as the geometric constraints, dictated by manufacturing and assembly processes of materials, they can be incorporated in the generative design codes. The article examines the possibility to also include the main conditions that enable the selective disassembly of the elements and their reuse at the end of life, avoiding the generation of parts that are not remanufacturable or reusable.

AbstractAcute carbon monoxide poisoning is the leading cause of intoxication from exogenous substances in the world. It is also a major cause of morbidity and mortality due to poisoning in the USA. In the USA, it determines to 50,000 visits per year in emergency departments with a mortality ranging from 1 to 3%. Although prevalence and incidence data reveal the large impact of carbon monoxide poisoning on public health, some studies have shown that errors in its diagnosis have a high incidence (30%) and that awareness campaigns have allowed the reduction of the same to 5%. In addition, many diagnostic and/or therapeutic errors were found both in small first aid situations and in the context of rescue units belonging to prestigious hospitals. To formulate a diagnosis, the collection of clues from the environment in which the patient is found is essential. Especially when the routine use of environmental gas detectors or handheld CO-oximeters is not possible, the emergency doctor, in addition to concentrating on the clinical presentation of the case, will have to give a quick overview of the patient and his environment. In addition to age, sex, and already known comorbidities, it is not irrelevant to evaluate socio-economic and cultural characteristics, hygiene conditions, habits, etc.The purpose of this study is to provide useful information to the doctor who comes first to the site of intoxication to reduce diagnostic and therapeutic errors in the pre- and intra-hospital phase as much as possible.

Premature fracture failure of blades occurred in four of a refinery's gas turbine compressors. In order to evaluate the probability of combustion instability's effects on failure of the blades; i.e., choking and chamber resonance problems, 3D models of the combustion chamber structure and combustion flow were studied with finite element and computation fluid dynamics codes, respectively. Comparison of results of combustion chamber natural frequencies with combustion swirl frequency showed that the chamber structure is not under resonance. In order to verify probability of choking, the combustion product flow's Mach number was studied. Results of the Mach number distribution showed that the flow is subsonic in the transition piece area but, due to existence of supersonic flow conditions near the swirl vanes it may become supersonic in some critical conditions. Thus, it is suggested to operators that, for avoiding choking probabilities, it is better that engine operation be maintained close to optimum design conditions. Results of simulations showed that the fracture of the blades is not due to combustion problems.

The cooling of a nuclear reactor depends on a suitable fluid flow pattern among its fuel elements aiming the removal of heat produced in the fuel. In case of light water reactors, an excess of heat drives the fluid to change its phase from liquid to vapor, significantly reducing its capacity to remove heat and leading the reactor to a Loss of Coolant Accident. Numerical simulations using a CFD code is a suitable tool to address this kind of problem and explore the conditions that should be avoided during the reactor operation. The commercial CFD codes had proven to be reliable to simulate with a high accuracy and confidence the thermal-hydraulics of a sort of equipment and systems, avoiding spending efforts and financial resources in the development of new codes that, essentially, perform the same tasks. Despite of it, the CFD codes must be validated, such as against experimental results. To comply with this objective, a benchmark fuel element was purposed and experimentally essayed to provide experimental results for CFD codes calibration. The results of this essay are provided to the four types of subchannels for a 5x5 PWR fuel element, with results provided as density and void fraction. This work presentes the preliminary results obtained with CFD numerical simulations using the ANSYS-CFX® code for the central subchannel with active rods for stead state operation. The results demonstrated that the ANSYS-CFX® is adequate to simulate with high accuracy the flow in this subchannel.

Abstract Background Cardiac amyloidosis (CA) is a rapidly progressive infiltrative cardiomyopathy, whose role is emerging as a not-so-rare disorder leading to heart failure (HF). Myocardial bridge (MB) is the most common inborn coronary artery variant, and its clinical relevance is still matter of debate. The exceptional coexistence of these two conditions could accelerate disease progression and worsen the already compromised clinical conditions. Case summary We present the case of a 76-year-old female patient experiencing relapsing HF decompensation and presenting to our center with dyspnea at rest and severe peripheral congestion. Echocardiogram showed severe concentric hypertrophy, severe biventricular contractile dysfunction and third degree diastolic disfunction. Coronary angiography excluded epicardial atherosclerotic disease, though displaying a long intramyocardial course of left anterior descending artery (LAD). Physiological invasive test was achieved in terms of instantaneous wave-free ratio (iFR), both at baseline and after inotropic and chronotropic stimuli, and attested hemodynamic significance. Concurrently, the diagnostic flowchart for cardiac amyloidosis was accomplished, by means of both invasive (periumbilical fat biopsy, bone marrow aspiration) and non-invasive tests (99mTc-diphosphonate scintigraphy, serum-urine immunofixation) that confirmed the suspect of primary amyloidosis. Acute heart failure therapy was personalized according to the singularity of the case, avoiding both nitrates and β-blockers, then first cycle of chemotherapy was started. Discussion Our clinical case shows a unique interaction between infiltrative cardiomyopathy and coronary artery abnormality. Amyloidosis can contribute to the ischemic burden of the MB and this may, in turn, abbreviate the path to heart failure decompensation.

Abstract Instability to high toroidal mode number (n) ballooning modes has been proposed as the primary gradient-limiting mechanism for tokamak equilibria with negative triangularity (δ) shaping, preventing access to strong H-mode regimes when δ is sufficiently negative. To understand how this mechanism extrapolates to reactor conditions, we model the infinite-n ballooning stability as a function of internal profiles and equilibrium shape using a combination of the CHEASE and BALOO codes. While the critical δ required for avoiding 2nd stability to high-n modes is observed to depend in a complicated way on various shaping parameters, including the equilibrium inverse aspect ratio, elongation and squareness, equilibria with negative triangularity are robustly prohibited from accessing the 2nd stability region, offering the prediction that that negative triangularity reactors should maintain L-mode-like operation. In order to access high-n 2nd stability, the local shear over the entire bad curvature region must be sufficiently negative to overcome curvature destabilization on the low field side. Scalings of the ballooning-limited pedestal height are provided as a function of plasma parameters to aid future scenario design.

In the event of natural disasters such as earthquakes, tsunamis, landslides, floods and droughts, water occupies a key role in disaster relief. The presence of water is important for drinking, cooking and support the refugee areas of environmental sanitation and avoiding disaster victims of diseases waterborn disease. Water problem in disaster conditions may occur partly as a result: the disturbance of water sources because change of water quality, to become turbid or salty, the destruction of a piping system, treatment plant damage, disruption of distribution systems, or the scarcity of water in evacuation areas. Introduction of water quality becomes important to determine which process technology will be used and saved investments in emergency conditions. Priority handling of clean water usually comes first in the refugee areas with communal system, because the need of water for bathing, washing and toilet is big enough, while for a drink in the early events during disaster dominated by bottled water, but for their long-term, they have to boil water. For remote areas and difficult to reach individuals who usually use system more simple and easily operated. Water Supply Technology for emergency response has the characteristic 1). Able to operate with all sorts of water conditions (flexible adaptable), 2). Can be operated easily, 3). Does not require much maintenance, 4). Little use of chemicals, and 5). Portable and easy removable (Mobile System). Keywords : Water Quality, Water Treatment Technology, Drinking Water, Emergency Response, filtration, ceramic filtration, Ultra filtration, Reverse Osmosis, Ultraviolet Sterilizer, Ozonizer, Disinfection.

Abstract Green’s functions with continuum spectra are a way of avoiding the strong bounds on new physics from the absence of new narrow resonances in experimental data. We model such a situation with a five-dimensional model with two branes along the extra dimension z, the ultraviolet (UV) and the infrared (IR) one, such that the metric between the UV and the IR brane is AdS5, thus solving the hierarchy problem, and beyond the IR brane the metric is that of a linear dilaton model, which extends to z → ∞. This simplified metric, which can be considered as an approximation of a more complicated (and smooth) one, leads to analytical Green’s functions (with a mass gap mg ∼ TeV and a continuum for s >$$ {m}_g^2 $$ m g 2 ) which could then be easily incorporated in the experimental codes. The theory contains Standard Model gauge bosons in the bulk with Neumann boundary conditions in the UV brane. To cope with electroweak observables the theory is also endowed with an extra custodial gauge symmetry in the bulk, with gauge bosons with Dirichlet boundary conditions in the UV brane, and without zero (massless) modes. All Green’s functions have analytical expressions and exhibit poles in the second Riemann sheet of the complex plane at s = $$ {M}_n^2 $$ M n 2 − iMnΓn, denoting a discrete (infinite) set of broad resonances with masses (Mn) and widths (Γn). For gauge bosons with Neumann or Dirichlet boundary conditions, the masses and widths of resonances satisfy the (approximate) equation s = −4$$ {m}_g^2{\mathcal{W}}_n^2 $$ m g 2 W n 2 [±(1 + i)/4], where $$ \mathcal{W} $$ W n is the n-th branch of the Lambert function.

Abstract The detection of GW190521 by the LIGO–Virgo collaboration has revealed the existence of black holes (BHs) in the pair-instability (PI) mass gap. Here, we investigate the formation of BHs in the PI mass gap via star – star collisions in young stellar clusters. To avoid PI, the stellar-collision product must have a relatively small core and a massive envelope. We generate our initial conditions from the outputs of a hydro-dynamical simulation of the collision between a core helium burning star (∼58 M⊙) and a main-sequence star (∼42 M⊙). The hydro-dynamical simulation allows us to take into account the mass lost during the collision (∼12 M⊙) and to build the chemical composition profile of the post-collision star. We then evolve the collision product with the stellar evolution codes parsec and mesa. We find that the post-collision star evolves through all the stellar burning phases until core collapse, avoiding PI. At the onset of core collapse, the post-collision product is a blue super-giant star. We estimate a total mass loss of about 1 M⊙ during the post-collision evolution, due to stellar winds and shocks induced by neutrino emission in a failed supernova. The final BH mass is ≈87 M⊙. Therefore, we confirm that the collision scenario is a suitable formation channel to populate the PI mass gap.