bluuebunny/crossref_metadata_2025 huggingface dataset:
FUNCTIONAL DESCRIPTION OF THE ZONING OF LOCAL TERRITORIES OF THE GLOBE BY QUANTITY AND DESTRUCTIVE ENERGY OF TECTONIC EXTREME ORIGIN SITUATIONS
Authors: Tiutiunyk V. , Chernogor L. , Kalugin V. , Agazade T.
Published: May 2020

In conditions of uneven distribution of sources of danger across the territory of the state, each territory has its own levels of natural, technogenic, social and military loads, which influence on the composition of forces, tactical and technical characteristics of the means of the functioning geoinformation security system, namely the national security system.
In Ukraine the civil defense system is functioning to ensure the implementation of state policy in the field of civil defense for protection of the population, territories, environment and property from emergencies by preventing such situations, eliminating their consequences and providing assistance to victims in peacetime and during a special period. The system consists of functional and territorial subsystems and is aimed to solving the issues of ensuring the necessary level of security of the state in the conditions of emergency. At the same time, the issues of implementation of the monitoring function and development of effective decisions by all local subsystems, which aimed at prevention and localization of different emergencies, remain completely open to the state.
In this paper in order to further develop the scientific and technical foundations for creating an artificial intelligence system for monitoring emergencies of tectonic origin have been presented the results of a mathematical description of the hierarchical clustering local territories of the globe in terms of the amount and of destructive energy of tectonic origin emergency situations. The results have been obtained by discriminant and canonical multivariate statistical analysis of the Earth's seismic activity in the Sun – Earth – Moon nonlinear energy interaction system. The discriminant and canonical analyzes of the results of hierarchical clustering (zoning) of the local territories of the globe according to the level of seismic activity were carried out using the statistical packages STATISTICA 6.1 and SPSS 2.0. The results obtained in this work are the basis for further comprehensive assessment of the interconnections between the main parameters of the Earth’s movement in the Sun – Earth – Moon system and the main parameters of the tectonic hazard of seismically active local territories of the Earth, aimed at developing the scientific and technical foundations for creating an artificial intelligence system for monitoring emergencies of tectonic origin.
Keywords: emergency, seismic activity, seismic hazard, emergency monitoring of tectonic origin, discriminant analysis, canonical analysis
FORMATION OF RESIDUAL STRENGTH OF STRUCTURAL FIBER IN CONDITIONS AFTER FIRE
Authors: Bilym P. , Rosokha V. , Nikitchenko О. , Garbuz A. , Zhiglo A.
Published: May 2020

The article presents the results of dynamic mechanical tests of fiberglass specimens under the conditions of the effects of intense heating on them, which corresponded to the development of a slowly developing fire.
It is established that with intensive heating at the initial stage of fire, the considered type of fiberglass loses its initial strength, but then, upon cooling, acquires increased rigidity, while maintaining sufficient integrity and relative structural functionality.
In our view, this increase is due to the significant increase in the carbon fraction in the polymer binder with the formation of a more densely packed structure due to the formation of sites with associated aromatic fragments. At the same time, the drop in strength occurs due to the formation of a sufficient number of voids (pores and cracks), the occurrence of which is characteristic of materials of organic nature (plastics based on synthetic polymers) in the process of thermal oxidation destruction under intense heating. It is established that the degree of conservation of the load-bearing strength of the fiberglass can be arranged in the following order: bending> stretching> compression. This behavior of the material indicates the use of additional structural measures when using it as the supporting elements of construction and technological structures.
The determining factor in the observed modification of the composite is the extent of the passage of the pyrolytic transformations of the polymer bond, which can indirectly be characterized by a change in the dynamic mechanical properties of the material under intense heating.
The main role is played by the binder component - the epoxidized naphthalene type oligomer, whose function is reduced to the ability to play a role in the volume of the polymer matrix of coke formation germs.
The above composition of components and the method of its production allows to develop polymeric composite materials without the use of additional components - flame retardants (retardants), which complicate the technology of obtaining the composite and in some cases reduce its initial physical and mechanical properties.
Keywords: fiberglass, residual strength, fire aftereffect, dynamic mechanical tests, epoxidised dinaftol
MODERN METHODS OF ANALYSIS OF THE CITY DEVELOPMENT
Authors: Denysenko N. , Tryhub О. , Zavialova A. , Vakulchyk I.
Published: May 2020

There has been substantiated the necessity of using modern methods of socio-economic and marketing analysis of city development in order to make effective strategic decisions. The sequence of conducting the SWOT analysis of an area is generalized. It is proved that the analysis of the area development involves, first and foremost, the search for territorial identity and uniqueness. A modern toolkit for conducting a SWOT analysis of an area is offered, which is an analysis of internal strengths and weaknesses, as well as external opportunities and threats and also justification of the most effective strategies for the area development.
It is stated that SWOT-analysis is a necessary element of research, a mandatory preliminary step while drawing up strategic and marketing plans of any level. The data obtained in the result of the analysis serve as the basis for the development of strategic goals and objectives of the area. SWOT analysis enables to assess whether the area has the internal strengths and resources to realize its capabilities and counter threats, and which internal weaknesses require an early elimination.
Creating a map of anchors - zones of gravity helps to justify the points of growth when developing strategic decisions. The example of the town of Lutsk shows the objects and territories that can attract potential customer - consumers and encourage the interest in visiting Lutsk increasing the consumer flow.
In order to study the strengths and weaknesses of the area in-depth, the real estate market was analyzed and residential real estate was broken down into spatial development categories in Lutsk. There are four categories of local territories in the town: developing, moderately prosperous, moderately depressed, and depressed
There has also been carried out a SWOT analysis of the mutual impact of opportunities and threats on the environment and the strengths and weaknesses of Lutsk. The analysis is presented in the form of tables. The factors are ranked by their importance and the final results of the analysis are formulated in the form of sound strategic decisions.
It is emphasized that under the current stage of development in Ukraine it is advisable to take into account the available resource potential, uniqueness and competitive advantages of a city/town to overcome weaknesses and threats when determining the optimal development strategy and making effective project decisions.
Keywords: strategic approach, city, center of gravity, SWOT analysis, spatial development.
PROJECT ACTIVITIES OF PUBLIC AUTHORITIES AS OBJECTS OF SCIENTIFIC RESEARCH
Authors: Khrenova-Shymkina R.
Published: May 2020

The article deals with the nature and content of project activity as an object of scientific research. It is determined that the project management toolkit provides opportunities for ensuring the efficiency of public administration and the need for its decentralization, facilitating business development by improving the provision of public services, while reducing their cost and complexity. The essence of the concept of project management has been investigated and the relationship of projects with the activities of public authorities, the government, which can be traced through the implementation of programs at the state level or measures to fulfill the commitments undertaken by local authorities, has been identified. Attention is drawn to the fact that the project activity of public authorities has a number of features, among which the key are its regulation (time constraint), compliance with community requests, focus on territorial unit development and openness. The author also suggested a scheme of project activity and considered all components of this process. Particular attention is paid to the factors that improve the effectiveness of project implementation: the knowledge component - human capital, process monitoring, sources of funding and communications. The article also presents the author's classification of the project activity of public authorities, depending on the goals, the main types of project activity were separated: social orientation (solving problems of overcoming poverty, preserving the health of the population, observing human rights, ensuring the well-being and safety of children, etc.); infrastructural character (development of public transport network, improvement of public services, improvement of logistics on roads, location and number of pre-school educational institutions, etc.); environmental orientation (environmental protection, conservation of reserves, construction of treatment plants and introduction of the best treatment technologies, development of secondary production, etc.); investment nature (development of recreation and tourism areas, the spread of digital technologies in public services (SMART technologies), implementation of joint projects with business companies within the framework of corporate social responsibility programs and public-private partnerships, etc.).
Keywords: project activity, public authorities, human capital, communications, monitoring.
CLUSTER ANALYSIS OF THE UKRAINE REGIONS ON THE LEVEL OF WASTE MANAGEMENT SYSTEM DEVELOPMENT
Authors: Khandogina О.
Published: May 2020

The cluster analysis of the regions of Ukraine by economic, environmental and social indicators characterizing regional economic development and development of the waste management system is carried out in the paper. Three groups of regions characterized by similar features are identified. The average values of the studied indicators by separate clusters are determined. It was established, for example, that the regions from the first cluster are characterized by a low level of the waste management system development, in the regions from the second group modern technologies of waste management is more actively introducing in comparison with other regions. Discriminant analysis was conducted. The results of the analysis show that regions are differentiated mostly by five indicators: average tariff for waste management for the population, financing of waste management system, area of landfills and damps, amount of waste collection per capita, the rate of waste recycling sector development. The developed model determines the distribution of regions into groups with an accuracy of 100% at the significance level p <0.005. Classification discriminatory functions were obtained for groups of regions. The indicators influenced the distribution of regions into clusters are established. The results of the analysis highlight the irregularity of regional waste management systems development. The cluster approach allows classifying regions of Ukraine according to complex of indicators. Differentiated strategies for improving the waste management system at regional level as well as comprehensive ratings of the regional waste management systems development could be developed on the basis of such analysis.
Keywords: municipal solid waste, regional development, waste management system, cluster analysis, discriminant analysis.
Pembangkitan Kode Sampa MBROLA untuk Lirik Pupuh Pucung Berdasarkan Padalingsa dan Diftong
Authors: Eka Giri Gunawan I Putu , Agung Indrawan I Gusti
Published: May 2020

Kurangnya minat masyarakat untuk belajar tembang bali akan mengakibatkan semakin hilangnya budaya bali. Salah satu faktor peyebab kurang tertarik nya masyarakat untuk belajar tembang bali adalah media pembelajaran tembang bali yang kurang menarik dan tidak interaktif. Pupuh pucung merupakan salah satu bagian dari sekar alit yang merupakan bagian tembang bali. Sekar alit/pupuh memiliki aturan dalam penulisan liriknya yang disebut dengan padalingsa yang terdiri dari guru wilangan yaitu jumlah suku kata dalam setiap barisnya, guru dingdong yaitu huruf vokal pada kata terakhir setiap barisnya dan guru gatra yaitu jumlah baris dalam satu baitnya. Penelitian ini akan menciptakan suatu aplikasi yang interaktif yang bisa digunakan untuk mencoba lirik dari pupuh pucung sesuai dengan aturan padalingsa pupuh pucung. Penelitian ini membahas bagaimana analisis dan konversi lirik pupuh pucung ke kode sampa yang digunakan di program sintesis suara MBROLA. Hasil dari penelitian ini adalah kode sampa MBROLA yang dibangkitkan berdasarkan aturan padalingsa dan diftong bahasa bali.
Cunning as a snake: Thomas More and the right to stay silent (with a long digression on Seneca)
Authors: Faro Giorgio
Published: May 2020

The article examines the reasons for silence in Thomas More, starting from his History of King Richard the III, considering then his actions as speaker of the House of Commons and later as Chancellor, and, finally, his refusal to take the oath to uphold the Acts of Succession and Supremacy. Another relevant subtopic takes a cue from Seneca's assertions about silence (in his Œdipus) to allow the author, after careful reading of a paper published by F. Mitjans on Moreana, to correct an assertion made, in an earlier essay, in regard to the Seneca details in Lockey's copy of Holbein's More family portrait, as well as to present a more analytical assessment of the relevance of Seneca's presence in More's works (only More's two latter works are taken into account here). It turns out that More cites Seneca more often than has been thought, but with certain fairly crucial reservations, which should—at least in part—explain More's apparent reluctance to quote Seneca's name: another case of silence, which needs to be probed.
Automated Determination of Friction Coefficient
Authors: Farmos Rudolf László , Hodgyai Norbert , Forgó Zoltán , Egyed-Faluvégi Erzsébet
Published: May 2020

The presented research is designed to meet a particular challenge facing the industry. Its aim is to automate the process of friction coefficient determination, using a method that enables quick and easy repeatability of measurements developed by S.C. Plasmaterm S.A in Târgu Mureş.
CAD Solution to Determine Points from Chipping Tool Solid Model Cutting Edges
Authors: Tolvaly-Roşca Ferenc , Máté Márton , Forgó Zoltán , Pásztor Judit
Published: May 2020

The Mixed CAD Generating Method, developed by the first author and presented in previous papers, is able to generate gear teeth gaps from a special points cloud. The generation method requires only a few specific points from the cutting edges of the generating tools. These points can be obtained in a first approach through a simple drawing of the cutting edges. The drawings can use either mathematical equations, or simply the construction and design principles of the cutting tools. In the case of multi-edge cutting tools of a higher level of complexity, or in case of the absence of the edge equations, there exists a simpler approach. It consists in building a solid model, or obtaining the solid model of the tools from the tool’s designer or manufacturer. In these cases, the generating points are downloaded from the solid model. This paper presents two possibilities of obtaining these points with usual CAD methods.
Impact of Different Photovoltaic Models on the Design of a Combined Solar Array and Pumped Hydro Storage System
Authors: Al-Masri Hussein M. K. , Magableh Sharaf K. , Abuelrub Ahmad , Saadeh Osama , Ehsani Mehrdad
Published: May 2020

The impact of different photovoltaic models for a combined solar array and pumped hydro storage system was investigated. Al-Wehda dam located in Harta city in the northern of Jordan was used to validate the approach. The two-diode (TD), single-diode (SD), and ideal single-diode (ISD) solar models were evaluated in terms of the solar array size, reliability, and ecological effects. The impoundment of Al-Wehda dam was taken as the upper reservoir of the pumped hydro facility of the proposed renewable energy system. It was found that the PV power is more accurately modelled by considering the recombination loss in the TD solar model. This leads to a more realistic sizing and precise system evaluation. Results were obtained using the particle swarm optimization (PSO) algorithm and the whale optimization algorithm (WOA) for validation purposes. For instance, the PSO results showed that the realistic TD model is reliable, with an index of reliability of 98.558%. Further, it is the most ecological solution with an annual emissions reduction of 21.5198 Gg. The optimized values are 44,840 solar panels and 65.052 M.m3 of the lower reservoir volume for the TD model. The number of PV panels are reduced by 16.67% and 7.93%, respectively, with the ISD and SD relative to the TD model.
Unsupervised Detection of Changes in Usage-Phases of a Mobile App
Authors: Chae Hoyeol , Kang Ryangkyung , Seok Ho-Sik
Published: May 2020

Under the fierce competition and budget constraints, most mobile apps are launched without sufficient tests. Thus, there exists a great demand for automated app testing. Recent developments in various machine learning techniques have made automated app testing a promising alternative to manual testing. This work proposes novel approaches for one of the core functionalities of automated app testing: the detection of changes in usage-phases of a mobile app. Because of the flexibility of app development languages and the lack of standards, each mobile app is very different from other apps. Furthermore, the graphical user interfaces for similar functionalities are rarely consistent or similar. Thus, we propose methods detecting usage-phase changes through object recognition and metrics utilizing graphs and generative models. Contrary to the existing change detection methods requiring learning models, the proposed methods eliminate the burden of training models. This elimination of training is suitable for mobile app testing whose typical usage-phase is composed of less than 10 screenshots. Our experimental results on commercial mobile apps show promising improvement over the state-of-the-practice method based on SIFT (scale-invariant feature transform).
Spectral Domain Optical Coherence Tomography Imaging Performance Improvement Based on Field Curvature Aberration-Corrected Spectrometer
Authors: Lee Seung Seok , Song Woosub , Choi Eun Seo
Published: May 2020

We designed and fabricated a telecentric f-theta imaging lens (TFL) to improve the imaging performance of spectral domain optical coherence tomography (SD-OCT). By tailoring the field curvature aberration of the TFL, the flattened focal surface was well matched to the detector plane. Simulation results showed that the spot in the focal plane fitted well within a single pixel and the modulation transfer function at high spatial frequencies showed higher values compared with those of an achromatic doublet imaging lens, which are commonly used in SD-OCT spectrometers. The spectrometer using the TFL had an axial resolution of 7.8 μm, which was similar to the theoretical value of 6.2 μm. The spectrometer was constructed so that the achromatic doublet lens was replaced by the TFL. As a result, the SD-OCT imaging depth was improved by 13% (1.85 mm) on a 10 dB basis in the roll-off curve and showed better sensitivity at the same depth. The SD-OCT images of a multi-layered tape and a human palm proved that the TFL was able to achieve deeper imaging depth and better contrast. This feature was seen very clearly in the depth profile of the image. SD-OCT imaging performance can be improved simply by changing the spectrometer’s imaging lens. By optimizing the imaging lens, deeper SD-OCT imaging can be achieved with improved sensitivity.
A Holistic Cybersecurity Maturity Assessment Framework for Higher Education Institutions in the United Kingdom
Authors: Aliyu Aliyu , Maglaras Leandros , He Ying , Yevseyeva Iryna , Boiten Eerke , Cook Allan , Janicke Helge
Published: May 2020

As organisations are vulnerable to cyberattacks, their protection becomes a significant issue. Capability Maturity Models can enable organisations to benchmark current maturity levels against best practices. Although many maturity models have been already proposed in the literature, a need for models that integrate several regulations exists. This article presents a light, web-based model that can be used as a cybersecurity assessment tool for Higher Education Institutes (HEIs) of the United Kingdom. The novel Holistic Cybersecurity Maturity Assessment Framework incorporates all security regulations, privacy regulations, and best practices that HEIs must be compliant to, and can be used as a self assessment or a cybersecurity audit tool.
Statistical Error Propagation Affecting the Quality of Experience Evaluation in Video on Demand Applications
Authors: Wahab Abdul , Ahmad Nafi , Schormans John
Published: May 2020

In addition to the traditional Quality of Service (QoS) metrics of latency, jitter and Packet Loss Ratio (PLR), Quality of Experience (QoE) is now widely accepted as a numerical proxy for the actual user experience. The literature has reported many mathematical mappings between QoE and QoS, where the QoS parameters are measured by the network providers using sampling. Previous research has focussed on sampling errors in QoS measurements. However, the propagation of these sampling errors in QoS through to the QoE values has not been evaluated before. This is important: without knowing how sampling errors propagate through to QoE estimates there is no understanding of the precision of the estimates of QoE, only of the average QoE value. In this paper, we used industrially acquired measurements of PLR and jitter to evaluate the sampling errors. Additionally, we evaluated the correlation between these QoS measurements, as this correlation affects errors propagating to the estimated QoE. Focusing on Video-on-Demand (VoD) applications, we use subjective testing and regression to map QoE metrics onto PLR and jitter. The resulting mathematical functions, and the theory of error propagation, were used to evaluate the error propagated to QoE. This error in estimated QoE was represented as confidence interval width. Using the guidelines of UK government for sampling in a busy hour, our results indicate that confidence intervals around estimated the Mean Opinion Score (MOS) rating of QoE can be between MOS = 1 to MOS = 4 at targeted operating points of the QoS parameters. These results are a new perspective on QoE evaluation and are of potentially great significance to all organisations that need to estimate the QoE of VoD applications precisely.
Analysis of Chronic Periodontitis in Tonsillectomy Patients: A Longitudinal Follow-Up Study Using a National Health Screening Cohort
Authors: Byun Soo Hwan , Min Chanyang , Kim Yong Bok , Kim Heejin , Kang Sung Hun , Park Bum Jung , Wee Ji Hye , Choi Hyo Geun , Hong Seok Jin
Published: May 2020

This study aimed to compare the risk of chronic periodontitis (CP) between participants who underwent tonsillectomy and those who did not (control participants) using a national cohort dataset. Patients who underwent tonsillectomy were selected from a total of 514,866 participants. A control group was included if participants had not undergone tonsillectomy from 2002 to 2015. The number of CP treatments was counted from the date of the tonsillectomy treatment. Patients who underwent tonsillectomy were matched 1:4 with control participants who were categorized based on age, sex, income, and region of residence. Finally, 1044 patients who underwent tonsillectomy were matched 1:4 with 4176 control participants. The adjusted estimated value of the number of post-index date (ID) CP did not reach statistical significance in any post-ID year (each of p > 0.05). In another subgroup analysis according to the number of pre- ID CP, it did not show statistical significance. This study revealed that tonsillectomy was not strongly associated with reducing the risk of CP. Even though the tonsils and periodontium are located adjacently, and tonsillectomy and CP may be related to bacterial inflammation, there was no significant risk of CP in patients undergoing tonsillectomy.
Aerodynamic Performance of a High-Speed Train Passing through Three Standard Tunnel Junctions under Crosswinds
Authors: Miao Xiujuan , He Kan , Minelli Guglielmo , Zhang Jie , Gao Guangjun , Wei Hongliang , He Maosheng , Krajnovic Sinisa
Published: May 2020

The aerodynamic performance of a high-speed train passing through tunnel junctions under severe crosswind condition was numerically investigated using improved delayed detached-eddy simulations (IDDES). Three ground scenarios connected with entrances and exits of tunnels were considered. In particular a flat ground, an embankment, and a bridge configuration were used. The numerical method was first validated against experimental data, showing good agreement. The results show that the ground scenario has a large effect on the train’s aerodynamic performance. The bridge case resulted in generally smaller drag and lift, as well as a lower pressure coefficient on both the train body and the inner tunnel wall, as compared to the tunnel junctions with flat ground and embankment. Furthermore, the bridge configuration contributed to the smallest pressure variation in time in the tunnel. Overall, the study gives important insights on complicated tunnel junction scenarios coupled with severe flow conditions, that, to the knowledge of the authors, were not studied before. Beside this, the results can be used for further improvements in the design of tunnels where such crosswind conditions may occur.
DFIQ, a Novel Quinoline Derivative, Shows Anticancer Potential by Inducing Apoptosis and Autophagy in NSCLC Cell and In Vivo Zebrafish Xenograft Models
Authors: Huang Hurng-Wern , Bow Yung-Ding , Wang Chia-Yih , Chen Yen-Chun , Fu Pei-Rong , Chang Kuo-Feng , Wang Tso-Wen , Tseng Chih-Hua , Chen Yeh-Long , Chiu Chien-Chih
Published: May 2020

Lung cancer is one of the deadliest cancers worldwide due to chemoresistance in patients with late-stage disease. Quinoline derivatives show biological activity against HIV, malaria, bacteriuria, and cancer. DFIQ is a novel synthetic quinoline derivative that induces cell death in both in vitro and in vivo zebrafish xenograft models. DFIQ induced cell death, including apoptosis, and the IC50 values were 4.16 and 2.31 μM at 24 and 48 h, respectively. DFIQ was also found to induce apoptotic protein cleavage and DNA damage, reduce cell cycle-associated protein expression, and disrupt reactive oxygen species (ROS) reduction, thus resulting in the accumulation of superoxide radicals. Autophagy is also a necessary process associated with chemotherapy-induced cell death. Lysosome accumulation and lysosome-associated membrane protein-2 (LAMP2) depletion were observed after DFIQ treatment, and cell death induction was restored upon treatment with the autophagy inhibitor 3-methyladenine (3-MA). Nevertheless, ROS production was found to be involved in DFIQ-induced autophagy activation and LAMP2 depletion. Our data provide the first evidence for developing DFIQ for clinical usage and show the regulatory mechanism by which DFIQ affects ROS, autophagy, and apoptosis.
Reliable Surrogate Modeling of Antenna Input Characteristics by Means of Domain Confinement and Principal Components
Authors: Pietrenko-Dabrowska Anna , Koziel Slawomir
Published: May 2020

A reliable design of contemporary antenna structures necessarily involves full-wave electromagnetic (EM) analysis which is the only tool capable of accounting, for example, for element coupling or the effects of connectors. As EM simulations tend to be CPU-intensive, surrogate modeling allows for relieving the computational overhead of design tasks that require numerous analyses, for example, parametric optimization or uncertainty quantification. Notwithstanding, conventional data-driven surrogates are not suitable for handling highly nonlinear antenna characteristics over multidimensional parameter spaces. This paper proposes a novel modeling approach that employs a recently introduced concept of domain confinement, as well as principal component analysis. In our approach, the modeling process is restricted to the region containing high-quality designs with respect to the performance figures of antennas under design, identified using a set of pre-optimized reference designs. The model domain is spanned by the selected principal components of the reference design set, which reduces both its volume and dimensionality. As a result, a reliable surrogate can be constructed over wide ranges of both operating conditions and antenna parameters, using small training datasets. Our technique is demonstrated using two antenna examples and is favorably compared to both conventional and constrained modeling approaches. Application case studies (antenna optimization) are also discussed.
Improved Predictive Control in Multi-Modular Matrix Converter for Six-Phase Generation Systems
Authors: Toledo Sergio , Maqueda Edgar , Rivera Marco , Gregor Raúl , Wheeler Pat , Romero Carlos
Published: May 2020

Distributed generation systems are emerging as a good solution as part of the response to the world’s growing energy demand. In this context multi-phase wind generation systems are a feasible option. These systems consist of renewable AC sources which requires efficient and controlled power conversion stages. This work proposes a novel predictive current control strategy that takes advantage of a multi-modular matrix converter topology in the power stage of a six-phase generation system. The proposed method uses a coupling signal between the modules to decrease the error and the total harmonic distortion compared to independent control of each module. Experimental results validate the new control strategy showing the improvement regarding the target parameters.
A Systematic PVQV-Curves Approach for Investigating the Impact of Solar Photovoltaic-Generator in Power System Using PowerWorld Simulator
Authors: Muhammed Abdullahi Oboh , Rawa Muhyaddin
Published: May 2020

With the recent growing interest in renewable energy integrated power systems across the globe for the various economic and environmental benefits, it is also significant to consider their influence on voltage stability in power systems. Therefore, this paper reports the static voltage stability impact of solar photovoltaic generation on power networks using PowerWorld simulator power-voltage (P–V)- and voltage-reactive power (V–Q)-curves to investigate the renewable energy generator model performance suitability. The impact of varying power factor control and static voltage droop control of a photovoltaic plant on the maximum generated power, threshold voltage profile and reactive power marginal loading has been examined. Besides, the concept of percentage change in voltage-power sensitivity has been systematically utilized to determine the optimal location for the solar photovoltaic generator on the power grid and the feasible penetrations have been defined for selected system buses. From the simulation results it can be concluded that in a steady-state analysis of the grid integrated power system the effects of power factor (pf) control and voltage droop control should be considered by power grid engineers for effective system operation and, equally, the application of percentage change in voltage-power sensitivity should be extended to real networks to determine the best positions for multiple installations of renewable energy resources.
Forced Convection in Porous Media Using Al2O3 and TiO2 Nanofluids in Differing Base Fluids
Authors: Saghir M. Z. , Welsford C.
Published: May 2020

The following work presents a numerical evaluation of the use of TiO2 and Al2O3 nanofluids operating with ethylene glycol and water as base fluids—as well as an experimental evaluation of Al2O3-water nanofluid. Both numerical and experimental systems were tested and operated under various flow and heat transfer conditions, including four flow rates and three heat fluxes. When compared, the numerical schemes and experimental results showed deviation of under two degrees Celsius. This led the authors to conclude that the numerical scheme accurately reflected the experimental conditions. When all combinations of mixtures were compared numerically, it was found that ethylene glycol provided the highest average Nusselt number, while water offered significantly lower pumping requirements. When comparing nanoparticles, it was found that, in a carrying-fluid of water, TiO2 had superior performance by approximately one percent.
Numerical–Experimental Performance Assessment of a Non-Concentrating Solar Thermoelectric Generator (STEG) Operating in the Southern Hemisphere
Authors: Calderón-Henao Nelson , Venturini Osvaldo José , Franco Emerson Henrique Medina , Eduardo Silva Lora Electo , Scherer Helton Fernando , Maya Diego Mauricio Yepes , Ando Junior Oswaldo Hideo
Published: May 2020

This study assesses the performance of a solid-state semiconductor-based hybrid photovoltaic-thermoelectric device that aims to harness both solar irradiance and heat dissipated from photovoltaic cells operating in Foz do Iguaçu city. Initially, the technologies involved, and the arrangement of the proposed device are presented; the modeling process of the generator operation under local operating conditions and taking into account solar energy availability is described later. The thermal energy harvesting brings out an average annual efficiency gain of 4.42% and a maximum efficiency increase of 6.05% (in the fall equinox) compared to standalone PV cell operation. The power output increase due to the utilization of the heat dissipated by the PV cells was substantial, reaching values ranging from 14.82% to 40.54%, depending on the time of year. The novelty of this research stems from the field power generation forecast, in southern hemisphere, for a new STEG device that combines photovoltaic cells and solid-state thermoelectric modules.
HousEEC: Day-Ahead Household Electrical Energy Consumption Forecasting Using Deep Learning
Authors: Kiprijanovska Ivana , Stankoski Simon , Ilievski Igor , Jovanovski Slobodan , Gams Matjaž , Gjoreski Hristijan
Published: May 2020

Short-term load forecasting is integral to the energy planning sector. Various techniques have been employed to achieve effective operation of power systems and efficient market management. We present a scalable system for day-ahead household electrical energy consumption forecasting, named HousEEC. The proposed forecasting method is based on a deep residual neural network, and integrates multiple sources of information by extracting features from (i) contextual data (weather, calendar), and (ii) the historical load of the particular household and all households present in the dataset. Additionally, we compute novel domain-specific time-series features that allow the system to better model the pattern of energy consumption of the household. The experimental analysis and evaluation were performed on one of the most extensive datasets for household electrical energy consumption, Pecan Street, containing almost four years of data. Multiple test cases show that the proposed model provides accurate load forecasting results, achieving a root-mean-square error score of 0.44 kWh and mean absolute error score of 0.23 kWh, for short-term load forecasting for 300 households. The analysis showed that, for hourly forecasting, our model had 8% error (22 kWh), which is 4 percentage points better than the benchmark model. The daily analysis showed that our model had 2% error (131 kWh), which is significantly less compared to the benchmark model, with 6% error (360 kWh).
Dual Targeting of Stromal Cell Support and Leukemic Cell Growth by a Peptidic PKC Inhibitor Shows Effectiveness against B-ALL
Authors: Ruiz-Aparicio Paola Fernanda , Vanegas Natalia-Del Pilar , Uribe Gloria Inés , Ortiz-Montero Paola , Cadavid-Cortés Camila , Lagos Jimmy , Flechas-Afanador Jessica , Linares-Ballesteros Adriana , Vernot Jean-Paul
Published: May 2020

Mesenchymal stem cells (MSC) favour a scenario where leukemic cells survive. The protein kinase C (PKC) is essential to confer MSC support to leukemic cells and may be responsible for the intrinsic leukemic cell growth. Here we have evaluated the capacity of a chimeric peptide (HKPS), directed against classical PKC isoforms, to inhibit leukemic cell growth. HKPS was able to strongly inhibit viability of different leukemic cell lines, while control HK and PS peptides had no effect. Further testing showed that 30% of primary samples from paediatric B-cell acute lymphoblastic leukaemia (B-ALL) were also strongly affected by HKPS. We showed that HKPS disrupted the supportive effect of MSC that promote leukemic cell survival. Interestingly, ICAM-1 and VLA-5 expression increased in MSC during the co-cultures with B-ALL cells, and we found that HKPS inhibited the interaction between MSC and B-ALL cells due to a reduction in the expression of these adhesion molecules. Of note, the susceptibility of B-ALL cells to dexamethasone increased when MSC were treated with HKPS. These results show the relevance of these molecular interactions in the leukemic niche. The use of HKPS may be a new strategy to disrupt intercellular communications, increasing susceptibility to therapy, and at the same time, directly affecting the growth of PKC-dependent leukemic cells.
Mitochondrial pH Nanosensors for Metabolic Profiling of Breast Cancer Cell Lines
Authors: Ripoll Consuelo , Roldan Mar , Contreras-Montoya Rafael , Diaz-Mochon Juan J. , Martin Miguel , Ruedas-Rama Maria J. , Orte Angel
Published: May 2020

The main role of mitochondria, as pivotal organelles for cellular metabolism, is the production of energy (ATP) through an oxidative phosphorylation system. During this process, the electron transport chain creates a proton gradient that drives the synthesis of ATP. One of the main features of tumoral cells is their altered metabolism, providing alternative routes to enhance proliferation and survival. Hence, it is of utmost importance to understand the relationship between mitochondrial pH, tumoral metabolism, and cancer. In this manuscript, we develop a highly specific nanosensor to accurately measure the intramitochondrial pH using fluorescence lifetime imaging microscopy (FLIM). Importantly, we have applied this nanosensor to establish differences that may be hallmarks of different metabolic pathways in breast cancer cell models, leading to the characterization of different metabophenotypes.
Liquid Biopsy for the Diagnosis of Viral Hepatitis, Fatty Liver Steatosis, and Alcoholic Liver Diseases
Authors: Shabangu Ciniso Sylvester , Huang Jee-Fu , Hsiao Hui-Hua , Yu Ming-Lung , Chuang Wan-Long , Wang Shu-Chi
Published: May 2020

During the progression from hepatitis to fibrosis, cirrhosis, and liver failure, the accumulation of stressed/damaged hepatocyte elements associated with liver inflammation is critical. The causes of hepatocyte injuries include viral hepatitis infections, alcoholic hepatitis, and non-alcoholic fatty liver disease. Hepatocyte-derived extracellular vesicles (Hep-EVs) released from stressed/damaged hepatocytes are partly responsible for liver disease progression and liver damage because they activate non-parenchymal cells and infiltrate inflammatory cells within the liver, which are in turn are an important source of EVs. This cell-to-cell signaling is prevalent during inflammation in many liver diseases. Accordingly, special emphasis should be placed on liquid biopsy methods for the long-term monitoring of chronic liver diseases. In the present review, we have highlighted various aspects of current liquid biopsy research into chronic liver diseases. We have also reviewed recent progress on liquid biopsies that focus on cell-free DNA (cfDNA), long non-coding RNA (lncRNA), and the proteins in EVs as potential diagnostic tools and novel therapeutic targets in patients with viral hepatitis, fatty liver steatosis, and alcoholic liver diseases.
Adherent-Invasive E. coli: Update on the Lifestyle of a Troublemaker in Crohn’s Disease
Authors: Chervy Mélissa , Barnich Nicolas , Denizot Jérémy
Published: May 2020

Besides genetic polymorphisms and environmental factors, the intestinal microbiota is an important factor in the etiology of Crohn’s disease (CD). Among microbiota alterations, a particular pathotype of Escherichia coli involved in the pathogenesis of CD abnormally colonizes the intestinal mucosa of patients: the adherent-invasive Escherichia coli (AIEC) pathobiont bacteria, which have the abilities to adhere to and to invade intestinal epithelial cells (IECs), as well as to survive and replicate within macrophages. AIEC have been the subject of many studies in recent years to unveil some genes linked to AIEC virulence and to understand the impact of AIEC infection on the gut and consequently their involvement in CD. In this review, we describe the lifestyle of AIEC bacteria within the intestine, from the interaction with intestinal epithelial and immune cells with an emphasis on environmental and genetic factors favoring their implantation, to their lifestyle in the intestinal lumen. Finally, we discuss AIEC-targeting strategies such as the use of FimH antagonists, bacteriophages, or antibiotics, which could constitute therapeutic options to prevent and limit AIEC colonization in CD patients.
Influence of Bovine Serum Albumin (BSA) on the Tribocorrosion Behaviour of a Low Carbon CoCrMo Alloy in Simulated Body Fluids
Authors: Yoneyama Choshun , Cao Shoufan , Igual Munoz Anna , Mischler Stefano
Published: May 2020

Tribocorrosion, as the interaction between mechanical wear and electrochemical corrosion, has been found to be the main problem causing the failure and limiting the lifetime of metal-on-metal artificial hip joints. Better understanding of the tribocorrosion mechanisms of CoCrMo alloys is needed in order to reduce the degradation of this alloy, especially in the presence of proteins as one of the organic components present in synovial fluid. In this study, tribocorrosion tests of a low carbon CoCrMo alloy in phosphate buffer solution (PBS) with and without bovine serum albumin (BSA) in two different concentrations at different applied potentials (passive and cathodic) were carried out. The results show that the effect of proteins on wear and friction was concentration and potential dependent. In the cathodic domain (absence of very thin passive film), wear was very low in all solutions and the friction was significantly reduced by the addition of BSA to PBS even at low BSA concentrations. However, in the passive domain, the friction and wear were found not to be affected when the BSA concentration was 0.5 g/L, while they were reduced when increasing the BSA concentration to 36 g/L. The tribocorrosion results were rationalized through an existing tribocorrosion model and the effect of BSA on wear and friction was explained by the consideration of physical factors such as changes in viscosity and double layer structure, because in the present results no tribofilm formation was observed.
Effect of Boron Content and Cooling Rate on the Microstructure and Boride Formation of β-Solidifying γ-TiAl TNM Alloy
Authors: Bernal Daniel , Chamorro Xabier , Hurtado Iñaki , Madariaga Iñaki
Published: May 2020

Boron is a unique and popular grain refiner element in cast titanium aluminide (TiAl) alloys, as it helps to improve mechanical properties if properly alloyed. However, the formation mechanism of different types of borides in cast TiAl alloys is not yet clearly understood. This study seeks to correlate the chemical composition and cooling rate during solidification of cast TiAl alloys, with the type of boride precipitated and the resulting microstructure. Several β-solidifying γ-TiAl alloys of the TNM family were cast, alloying boron to a starting Ti-44.5Al-4Nb-1Mo-0.1B (at.%) alloy. The alloys were manufactured with an induction skull melting furnace and poured into a stepped 2, 4, 8 and 16 mm thickness mold to achieve different cooling rates. On one hand, the results reveal that boron contents below 0.5 at.% and cooling rates during solidification above 10 K/s promote the formation of detrimental ribbon borides. On the other hand, boron contents above 0.5 at.% and cooling rates during solidification below 10 K/s promote the formation of a refined microstructure with blocky borides. Finally, the formation mechanisms of both ribbon and blocky borides are proposed.
Residual Stress and Microstructure of a Ti-6Al-4V Wire Arc Additive Manufacturing Hybrid Demonstrator
Authors: Mishurova Tatiana , Sydow Benjamin , Thiede Tobias , Sizova Irina , Ulbricht Alexander , Bambach Markus , Bruno Giovanni
Published: May 2020

Wire Arc Additive Manufacturing (WAAM) features high deposition rates and, thus, allows production of large components that are relevant for aerospace applications. However, a lot of aerospace parts are currently produced by forging or machining alone to ensure fast production and to obtain good mechanical properties; the use of these conventional process routes causes high tooling and material costs. A hybrid approach (a combination of forging and WAAM) allows making production more efficient. In this fashion, further structural or functional features can be built in any direction without using additional tools for every part. By using a combination of forging basic geometries with one tool set and adding the functional features by means of WAAM, the tool costs and material waste can be reduced compared to either completely forged or machined parts. One of the factors influencing the structural integrity of additively manufactured parts are (high) residual stresses, generated during the build process. In this study, the triaxial residual stress profiles in a hybrid WAAM part are reported, as determined by neutron diffraction. The analysis is complemented by microstructural investigations, showing a gradient of microstructure (shape and size of grains) along the part height. The highest residual stresses were found in the transition zone (between WAAM and forged part). The total stress range showed to be lower than expected for WAAM components. This could be explained by the thermal history of the component.