bluuebunny/crossref_metadata_2025 huggingface dataset:
Analyzing different numerical linearization methods for the dynamic model of a turbofan engine
Authors: Montazeri-Gh Morteza , Rasti Ali
Published: May 2019

State equations of aircraft engine dynamics usually required for controller design, are not available in closed form, so the dynamic models are commonly linearized numerically. Development of model-based controllers for aeroengine in the recent years necessitates the use of accurate linear models. However, there is no comprehensive study about the accuracy of the linear models obtained from nonlinear engine models. In this paper, the accuracy of different numerical linearization methods for linearizing the dynamic model of a turbofan engine is investigated. For this objective, a thermodynamic model of a two-spool turbofan engine is considered and three various numerical linearization methods are defined. The first method is based on the perturbation technique, including ordinary and central difference perturbation. The second one is a system identification method and the third one is tuning the elements of the matrices of the linear state-space model using genetic algorithm. The accuracy analysis of the presented procedures is performed for both single-input and double-input cases. In the single-input case, the fuel mass flow rate and in the double-input, in addition to the fuel, the bleed air taken from between the two compressors are considered as control variables. Finally, by defining different error criterions, the accuracy of the linearization methods is evaluated. The results show that the linear model obtained from system identification and central difference perturbation methods have higher percentage of compliances compared to the others.
Study on horizontal vibration characteristics of high-speed elevator with airflow pressure disturbance and guiding system excitation
Authors: Liu Jie , Zhang Ruijun , He Qin , Zhang Qing
Published: May 2019

This paper aims to study the horizontal vibration dynamic characteristics of high-speed elevator by considering the combined effect of airflow and guiding system. The relationships of lateral force and overturning moment with horizontal displacement, deflection angle displacement and rated speed of the car are mathematically solved, and the horizontal vibration dynamic model of the car under the two excitations is established. For case model, the natural frequency and horizontal vibration response of the car are studied, and the guide-rail excitation frequency and car natural frequency are compared and analyzed. The results indicate that the higher the rated speed is, the more obvious the resonance phenomenon between the guide-rail and car will be in a certain range; the effect of airflow on horizontal vibration acceleration of the car with a speed lower than 6 m/s is small, but when the speed is over 6 m/s, the airflow will greatly affect the single-peak value of horizontal vibration acceleration, which is approximately a quadratic relationship; the deflection angle displacement has an increasing influence on horizontal vibration dynamic response with the increasing speed. The conclusions provide a theoretical guidance for the research and control on the horizontal vibration of high-speed elevator.
Microhardness evolution of pure titanium deformed by equal channel angular extrusion
Authors: Attarilar Shokouh , Salehi Mohammad-Taghi , Djavanroodi Faramarz
Published: May 2019

Microhardness homogeneity was assessed on commercial pure titanium processed by equal channel angular extrusion (ECAE). The operation was performed with die channel angle of 90° and processing temperature of 450 °C by route BC up to six passes. The Vickers microhardness measurements were investigated on both cross-sectional and longitudinal planes of the annealed, one-, two-, four-, and six-pass ECAEed titanium. It was found that the application of the process and the addition of pass numbers lead to the improvement of hardness magnitude. It was shown that there are some areas of microhardness heterogeneity in surrounding and bottom regions of the one-pass and two-pass specimens at the cross-sectional plane which is slightly disappeared by adding the pass numbers. Furthermore, there is a suitable amount of hardness homogeneity in the longitudinal plane, irrespective of the specimen condition. It can be concluded that a desirable homogeneity of hardness can be attained after imposing six passes of ECAE process on both cross-sectional and longitudinal planes of titanium.
Se diriger vers l’usine 4.0 chez Orano
Authors:   Direction de l’innovation, Orano
Published: May 2019

Au coeur du projet d’entreprise d’Orano, l’innovation et la digitalisation sont des rouages majeurs de l’action au quotidien. L’innovation est incontournable pour améliorer les performances industrielles du groupe, mais aussi la sûreté des opérations, l’ergonomie des postes de travail et pour transformer les méthodes de travail.
Assessment of tax subjects’ interaction under uncertainty of socio-economic processes
Authors: Kucherova Hanna , Serhieieva Liudmyla , Bilska Olha
Published: May 2019

Topicality of research into interactions between tax environment subjects is justified by growing uncertainty of changes in socio-economic processes. The aim of this study is to assess interaction between taxpayers, controlling bodies and public authorities in view of dominant paradigms and results of expert and sociological research on subjects with regard to the degree of their influence on tax environment climate. Interaction is defined as a certain type of relations between subjects that result in developing mutual influence which induces corresponding changes of their states. Interaction is essentially a poorly structured category, which dictates a need to use soft modeling and subjective evaluation methods (matrix models). According to the degree of influence on tax environment climate, public authorities are proved to be the most influential subject, while taxpayers are found to be the least influential. Summative value of subjects’ interaction is set as Very Good. It is determined by taxpayers’ data as the best among other subjects. Based on the analysis of dynamics in parameters and activity of interaction subjects it is argued that in order to improve subjects’ interaction productivity, it is appropriate to improve the mechanisms of subjects’ interaction with public authorities of all others.
Forecasting cryptocurrency prices time series using machine learning approach
Authors: Derbentsev Vasily , Datsenko Natalia , Stepanenko Olga , Bezkorovainyi Vitaly
Published: May 2019

This paper describes the construction of the short-term forecasting model of cryptocurrencies’ prices using machine learning approach. The modified model of Binary Auto Regressive Tree (BART) is adapted from the standard models of regression trees and the data of the time series. BART combines the classic algorithm classification and regression trees (C&RT) and autoregressive models ARIMA. Using the BART model, we made a short-term forecast (from 5 to 30 days) for the 3 most capitalized cryptocurrencies: Bitcoin, Ethereum and Ripple. We found that the proposed approach was more accurate than the ARIMA-ARFIMA models in forecasting cryptocurrencies time series both in the periods of slow rising (falling) and in the periods of transition dynamics (change of trend).
Model for assessment of the financial security level of the enterprise based of the desirability scale
Authors: Hryhoruk Pavlo , Khrushch Nila , Grygoruk Svitlana
Published: May 2019

Modern economic realities of Ukraine in the conditions of growing destabilizing influences of external and internal environment convincingly prove that each year the influence of various threats on the level of financial security of economic entities increases. This necessitates constant monitoring of the financial security level in order to timely detect and neutralize possible crisis phenomena as a result of its decrease. The study aims to assess the financial security level of enterprises based on the theory of comprehensive assessment. The scientific and methodical approach to design a composite index of financial security and the identifying its level based on the double use of Harrington's desirability scale is proposed. The resulting model was tested on the particular enterprise data. The proposed approach may be used for another set of partial indicators, as well as in assessing the level of financial security at the national level. The results of the study may serve as the basis for making managerial decisions on raising the business entities financial security level and public administration.
Predicting activity results of the specialized tour operator
Authors: Drobotova Marina , Krasnomovets Viktoriia , Radchenko Olga , Romanov Artur
Published: May 2019

Hospitality provides wide opportunities for entrepreneurship. Feasibility and forecasting of results have always been relevant for implementation of entrepreneurial ideas. Aim of the study is to clarify specifics of forecasting of specialized tour operators’ activities. Forecasting methods in tourism, as a rule, are based on opinion polls and extrapolation techniques. Difficulties with forecasting of results are related to indefinite part of specialized tours in overall volume of tours. And for every specialized tour this part depends from character and number of factors, which define demand for tourist product. Result of the study is the proposed algorithm for finding of planned sales of specialized tours for ensuring of profitable activities. With the example of gastronomical tours, which have good perspectives in Ukraine, it is proved that planning of more than 25-30% of specialized tours in overall sales of tours is not feasible. Finding of this research can be applied to product development, as well as marketing and strategic planning.
Improvement of bankruptcy probability model based on the analysis of industrial enterprises of Ukraine
Authors: Melikhova Tetiana , Makarenko Andriy , Mikhailytsa Olena , Pozhuyev Andriy
Published: May 2019

In present work, the peculiarities of simulation model of enterprises bankruptcy probability that exist in European, world and domestic practices were considered. The scientific econometric approach was applied to determine the overall presence and strength of the relation between the economic indicators of industrial enterprises. A financial analysis of large industrial manufactures in the region of Ukraine was conducted. To form the information base of the study, the authors estimated liquidity, solvency, business activity and profitability ratios that affect the financial condition of enterprises. They revealed the most significant ratios of financial condition analysis. According to the analysis of existing models of bankruptcy probability in the context of these industrial enterprises, an improved model for assessing the risk of bankruptcy was proposed and evaluated. The proposed model for estimating the probability of bankruptcy, taking into account the influence of the most significant ratios of financial analysis, confirmed that the percentage of provided bankruptcies and stable activities are acceptable and indicate high quality of the resulting equation. The IBM SPSS Statistics system was used to process the data, check the assumptions and prepare valid conclusions. The improved model will allow it to be used in the practice of diagnosing the probability of bankruptcy of industrial enterprises, which will help identify the threat of bankruptcy in time and ensure stable operation of the industrial enterprise.
Globalization processes in the modern world challenging the national economy development
Authors: Kasych Alla , Vochozka Marek
Published: May 2019

The article studies theoretical, methodological and analytical aspects of the globalization processes development, which increasingly affect the economic dynamics of a particular country. Synthesis of scientific approaches by leading scientists allows establishing the key characteristics and forms of globalization. The authors highlight ecological and cultural globalization, which increasingly affect economic processes. Analytical studies have been conducted in the context of establishing and substantiating maj or challenges that are increasingly complex and large-scale. Thus, the nature of the challenges is identified in terms of opportunities and threats to the development of the national economy. This article identifies a possible list of globalisation challenges through their actions as opportunities or threats. Substantiated by the authors the key development trends of globalization evidences of its versatility, multi-vectoral focus and interdependence of forms.The authors suggest the key measures for responding to the challenges of the “catching-up” economy globalization.
Synthesis of Novel C
2-Symmetric Sulfur-Based Catalysts: Asymmetric Formation of Halo- and Seleno-Functionalized Normal- and Medium-Sized Rings
Authors: Jana Sadhan , Verma Ajay , Rathore Vandana , Kumar Sangit
Published: May 2019

The synthesis of novel, highly functionalized, C
2-symmetric sulfur-based catalysts is developed and their catalytic applications are explored in asymmetric bromo-, iodo- and seleno-functionalizations of alkenoic acids. This protocol provides the corresponding normal- and medium-sized bromo, iodo and selenolactones in up to 98% yield and 83% stereoselectivity.
Smell Preservation following Unilateral Endoscopic Transnasal Approach to Resection of Olfactory Groove Meningioma: A Multi-institutional Experience
Authors: Orgain Carolyn A. , Kuan Edward C. , Alvarado Raquel , Adappa Nithin D. , Jonker Benjamin P. , Lee John Y. K. , Palmer James N. , Winder Mark , Harvey Richard J.
Published: May 2019

Introduction Olfactory groove meningiomas (OGMs) are often associated with loss of smell following resection. Loss of smell has a measurable impact on quality of life. Smell preservation has been previously described in open approaches for early stage or unilateral OGMs. Evidence of smell preservation in endoscopic approaches is lacking.

Design A multi-institutional retrospective review was performed on consecutive patients who underwent unilateral endoscopic endonasal resection of OGM. A gross total resection was achieved with preservation of the contralateral olfactory cleft and bulb. Olfactory function was assessed with a six-point olfactory symptom score and the Sniffin' Sticks 12-item smell identification test (SS-12). Contralateral olfactory bulb volume was measured on postoperative magnetic resonance imaging.

Results Four patients (age 42.0 ± 7.5, 75% female) were assessed. Olfactory function was assessed at 21.8 ± 5.6 months following surgery. All patients reported some degree of smell preservation (75% described a slight/mild impairment in smell or better). Olfactory identification was preserved with an SS-12 score of 9 ± 1.4 (anosmia defined as ≤6). The olfactory bulb volume was calculated to be 47.4 ± 15.9 mm3 (normal >40 mm3).

Conclusion Smell preservation is possible following unilateral endoscopic endonasal resection of carefully selected OGM.
Cluster Preface: Electrochemical Synthesis and Catalysis
Authors: Kawamata Yu , Baran Phil S.
Published: May 2019

Yu Kawamata was born in Japan in 1988, and he completed his undergraduate education at Kyoto University. He obtained his master’s degree and his Ph.D. at the same university under the supervision of Professor Keiji Maruoka, and he undertook a short-term internship at The Scripps Research Institute working on natural product synthesis with Professor Phil S. Baran. Upon completion of his doctoral studies, he returned to the Baran laboratory as a research associate and currently is pursuing his postdoctoral studies on organic electrochemistry.Phil S. Baran was born in New Jersey in 1977 and completed his undergraduate education at New York University in 1997. After earning his Ph.D. at The Scripps Research Institute (TSRI) in 2001, he pursued postdoctoral studies at Harvard University until 2003, at which point he returned to TSRI to begin his independent career. He was promoted to the rank of professor in 2008 and is currently the Darlene Shiley Professor of Chemistry. The mission of his laboratory is to educate students at the intersection of fundamental organic chemistry and translational science.
Investigation of L-Carnitine Concentrations in Treated Patients with Maple Syrup Urine Disease
Authors: Kumru Burcu , Oztürk Hismi Burcu
Published: May 2019

Maple syrup urine disease (MSUD), also known as branched-chain α ketoaciduria, is a metabolic disorder caused by an inborn deficiency in the activity of the branched-chain α-ketoacid dehydrogenase complex. Severe neurological damage occurs in most patients with MSUD although the exact mechanism of neurotoxicity still remains unknown. Studies have suggested that neuropathology in patients with MSUD may be related to oxidative stress. L-carnitine mediates the transport of fatty acids into the mitochondria that are required for β-oxidation and ATP production. Along with the important roles it plays in lipid metabolism, L-carnitine also protects tissues from oxidative damage through its antioxidant properties. The study included a total of 15 patients with MSUD who attended regular follow-up visits, and 15 age-matched healthy control subjects, and aimed to investigate L-carnitine levels in treated patients with MSUD and healthy control subjects. L-carnitine levels were found to be significantly lower in the patient group than in the healthy controls. No significant correlation was identified between the plasma branched-chain amino acids leucine, isoleucine, valine, and L-carnitine levels. Patients with MSUD can be treated with adjuvant therapy with L-carnitine supplementation.
Trametinib Induces Neurofibroma Shrinkage and Enables Surgery
Authors: Vaassen Pia , Dürr Nikola , Röhrig Andreas , Willing Rainer , Rosenbaum Thorsten
Published: May 2019

Plexiform neurofibromas are congenital peripheral nerve sheath tumors characteristic of neurofibromatosis type 1 (NF1)—a frequent neurocutaneous disorder caused by mutations of the NF1 tumor suppressor gene. Since plexiform neurofibromas are a major cause of the burden of disease and may also progress to malignancy, many efforts have been undertaken to find a cure for these tumors. However, neither surgery nor medication has so far produced a breakthrough therapeutic success. Recently, a clinical phase I study reported significant shrinkage of plexiform neurofibromas following treatment with the MEK inhibitor selumetinib. Here, we report an 11-year-old NF1 patient with a large plexiform neurofibroma of the neck that had led to a sharp-angled kinking of the cervical spine and subsequent myelopathy. Although surgical stabilization of the cervical vertebral column was urgently recommended, the vertebral column was inaccessible due to extensive tumor growth. In this situation, treatment with the MEK inhibitor trametinib was initiated which resulted in a 22% reduction in tumor volume after 6 months of therapy and finally enabled surgery. These data show that MEK inhibitors may not lead to complete disappearance of NF1-associated plexiform neurofibromas but can be an essential step in a multimodal therapeutic approach for these tumors. The course of our patient suggests that MEK inhibitors are likely to play a significant role in providing a cure for one of the most devastating manifestations of NF1.
Oxytocin and Oxytocinase in the Obese and Nonobese Parturients during Induction and Augmentation of Labor
Authors: De Tina Annemaria , Juang Jeremy , McElrath Thomas F. , Baty Jack D. , Palanisamy Arvind
Published: May 2019

Objective To investigate differences in oxytocin (OXT) biodistribution between nonobese and obese parturients during labor.

Study Design Patients with body mass index (BMI) of either ≥ 18 ≤ 24.9 kg/m2 (“nonobese”) or ≥ 30 kg/m2 (“obese”) undergoing elective induction of labor were included (N = 25 each). Blood samples were collected at baseline (T0), and 20 minutes after maximal OXT augmentation or adequate uterine contractions (T1) for OXT and oxytocinase assays. A mixed-model repeated-measures analysis of variance was used to test for group versus time interaction and analysis of covariance to detect a difference in OXT level at T1. Data presented as mean ± standard deviation or median (interquartile range), with p < 0.05 considered significant.

Results The mean BMIs (kg/m2) were 22.1 ± 1.6 and 35.9 ± 5.1 in the nonobese and obese groups, respectively. No differences were observed in either the duration of OXT infusion, total dose of OXT, or plasma OXT (pg/mL) either at T0 or T1. However, plasma oxytocinase (ng/mL) was significantly lower at T0 (1.41 [0.67, 3.51] vs. 0.40 [0.29, 1.12]; p = 0.03) in the obese group.

Conclusion We provide preliminary evidence that the disposition of OXT may not be different between obese and nonobese women during labor.
Near-infrared electroluminescence from metal-oxide-semiconductor devices with erbium-doped gadolinium oxide on silicon
Authors: Jin Chunyan , Liu Junqing , Sun Jiaming
Published: May 2019

Metal-oxide semiconductor (MOS) devices with Er-doped gate oxides as the light-emitting layers are considered as one of the most promising strategies to achieve silicon-based electroluminescence (EL). In this work, Er-doped Gd2O3 (Gd2O3:Er) films were grown on silicon by atomic layer deposition. The main cubic Gd2O3 phase and hexagonal Gd9.33(SiO4)6O2 phase were obtained in Gd2O3:Er films after thermal annealing treatment. Moreover, 900 °C and 1100 °C were identified as the optimal annealing temperatures for the photoluminescence from Gd2O3 phase and Gd9.33(SiO4)6O2 phase films, respectively. Based on this, the MOS devices were further fabricated with annealed Gd2O3:Er films as the light-emitting layers. Analysis on the current-voltage characteristics of the MOS devices indicates that the electron transportation at the EL-enabling voltages is dominated by Fowler-Nordheim tunneling. More importantly, Er-related EL in the near-infrared region from MOS devices was detected at ∼1530 nm as a function of the Er dopant concentration. The external quantum efficiency reaches 4% for the 900 °C-annealed Gd2O3:0.47%Er MOS device and 8% for the 1100 °C-annealed Gd9.33(SiO4)6O2:2.97% Er MOS device. It is believed that this work has laid the foundation for developing near-infrared silicon-based emitters using Gd2O3:Er films.
Observations of shock-induced chemistry with subnanosecond resolution
Authors: Olles Joseph D. , Wixom Ryan R. , Knepper Robert , Tappan Alexander S.
Published: May 2019

We report observations of the effects of shock-induced chemical reactions that build to a steady detonation in an energetic material. The chemical reactions in certain materials initiate and build quickly, such that traditional characterization techniques for energetics cannot provide the spatial fidelity necessary to resolve the onset and build-up of reactions. In this work, physical vapor deposition was used to create films of an energetic material with precisely controlled thicknesses to investigate the growth to detonation resulting from shock-induced chemical reactions with microscale spatial resolution. Finite duration shocks were supplied from a well-defined electrically-driven flyer. The velocity of the transmitted shock was measured by photonic Doppler velocimetry with subnanosecond resolution. Initiation experiments were performed on deposited hexanitrostilbene samples ranging from 30 to 150 μm thickness to observe the emergent effects of chemical energy release. The resulting output interface velocity was observed to increase from that predicted for an unreacted shock to that of a chemically supported detonation within 100 μm. A build-up to detonation has not previously been quantified in such a short distance.
Self-organizing plasma behavior in RF magnetron sputtering discharges
Authors: Panjan Matjaž
Published: May 2019

Self-organized plasma structures, called spokes, have been previously reported for continuous and pulsed magnetron discharges. Here, we demonstrate that spokes also form in the oscillatory RF magnetron sputtering (RFMS) regime. We used an intensified charge-coupled device camera and electrical probes to investigate the rotating plasma patterns. The spokes in RFMS were compared to the spokes in classical DC magnetron sputtering (DCMS) at similar discharge conditions. In both regimes, stable plasma patterns were observed for a wide range of discharge parameters. For similar gas pressures and discharge powers, the number of spokes in the RFMS regime was always larger than that in the DCMS regime. The number of spokes changed sequentially when the working gas pressure was increased for both magnetron operations. In the DCMS regime, a single spoke was observed at the lowest argon pressure (0.25 Pa), and a second spoke was observed only at the highest pressure (2 Pa). In the same pressure range, the plasma in the RFMS regime displayed four spokes at the lowest pressure and six or seven spokes at the highest pressure. The influence of discharge power on the number of spokes was less pronounced for both magnetron regimes. We analyzed the spoke patterns by examining the inelastic collisions between electrons and argon atoms. For this purpose, we simulated the dissipation of electron energy in the drift direction and compared the calculations to the length and number of spokes for particular discharge conditions. Overall, the simulations agree well with the observed plasma patterns in DCMS and RFMS.
On-demand droplet loading of ultrasonic acoustic levitator and its application for protein crystallography experiments
Authors: Tsujino Soichiro , Shinoda Akira , Tomizaki Takashi
Published: May 2019

Higher throughput has been ever demanded in the state-of-the-art protein crystallography beamlines for applications such as the screening of drug targets in protein-ligand complex structures at room temperature. As a potential method to achieve an order of magnitude higher throughput, we explore capturing of ejected droplets by an acoustic levitator to remotely load single protein crystal samples to an acoustic levitation diffractometer at the Swiss Light Source synchrotron facility. The results from X-ray diffraction experiments support the feasibility of this method as a fully automated sample delivery for high-throughput serial crystallography experiments using the acoustic levitation.
A new tool to assess ecosystem health in large subtropical reservoirs: Development and validation of a Planktonic Index of Biotic Integrity
Authors: Pomari Juliana , Kane Douglas D. , Ferreira Rosa A. R. , Nogueira Marcos G.
Published: May 2019

We developed and validated a Planktonic Index of Biotic Integrity for subtropical reservoirs to assess their ecosystem health. For this purpose, we analyzed the phytoplankton and zooplankton communities and determined reservoir trophic status in the Paranapanema River system (Southeast Brazil). Eleven dams were constructed in the main course of this river to supply hydropower plants. Three of the reservoirs are accumulation systems (i.e. with high water retention times), whereas the others are run-of-the-river systems. For the study the three larger reservoirs (Jurumirim, Chavantes and Capivara) were selected. Physical, chemical, and biological (phytoplankton and zooplankton) data were obtained in two sampling campaigns carried out in March (wet season) and October (dry season) of 2011. For each reservoir we sampled six stations, arranged on a gradient established between the lotic (Paranapanema River entrance) and lentic (dam) areas. According to the Trophic State Index for tropical/subtropical reservoirs, the sampling stations were categorized between ultraoligotrophic and mesotrophic. Four metrics achieved significant discrimination (out of a set of 20 candidate metrics). The individual metric scores were summed to provide a Planktonic Index of Biotic Integrity score, which ranged as Mesotrophic (4-9), Oligotrophic (10-14) and Ultraoligotrophic (15-20), corresponding to the classification of fair, good and excellent, respectively. Following the longitudinal sequence, Jurumirim was classified as Oligotophic (Good) and both Chavantes and Capivara as Ultraoligotrophic (Excellent). This study demonstrated that the Planktonic Index of Biotic Integrity is a potential tool for monitoring large subtropical reservoirs, as planktonic organisms are sensitive to environmental changes and this index integrates distinct temporal and spatial scales.
RAB6 and microtubules restrict protein secretion to focal adhesions
Authors: Fourriere Lou , Kasri Amal , Gareil Nelly , Bardin Sabine , Bousquet Hugo , Pereira David , Perez Franck , Goud Bruno , Boncompain Gaelle , Miserey-Lenkei Stéphanie
Published: May 2019

To ensure their homeostasis and sustain differentiated functions, cells continuously transport diverse cargos to various cell compartments and in particular to the cell surface. Secreted proteins are transported along intracellular routes from the endoplasmic reticulum through the Golgi complex before reaching the plasma membrane along microtubule tracks. Using a synchronized secretion assay, we report here that exocytosis does not occur randomly at the cell surface but on localized hotspots juxtaposed to focal adhesions. Although microtubules are involved, the RAB6-dependent machinery plays an essential role. We observed that, irrespective of the transported cargos, most post-Golgi carriers are positive for RAB6 and that its inactivation leads to a broad reduction of protein secretion. RAB6 may thus be a general regulator of post-Golgi secretion.
The complex of MCMV proteins and MHC class I evades NK cell control and drives the evolution of virus-specific activating Ly49 receptors
Authors: Železnjak Jelena , Lisnić Vanda Juranić , Popović Branka , Lisnić Berislav , Babić Marina , Halenius Anne , L’Hernault Anne , Roviš Tihana Lenac , Hengel Hartmut , Erhard Florian , Redwood Alec J. , Vidal Silvia M. , Dölken Lars , Krmpotić Astrid , Jonjić Stipan
Published: May 2019

CMVs efficiently target MHC I molecules to avoid recognition by cytotoxic T cells. However, the lack of MHC I on the cell surface renders the infected cell susceptible to NK cell killing upon missing self recognition. To counter this, mouse CMV (MCMV) rescues some MHC I molecules to engage inhibitory Ly49 receptors. Here we identify a new viral protein, MATp1, that is essential for MHC I surface rescue. Rescued altered-self MHC I molecules show increased affinity to inhibitory Ly49 receptors, resulting in inhibition of NK cells despite substantially reduced MHC I surface levels. This enables the virus to evade recognition by licensed NK cells. During evolution, this novel viral immune evasion mechanism could have prompted the development of activating NK cell receptors that are specific for MATp1-modified altered-self MHC I molecules. Our study solves a long-standing conundrum of how MCMV avoids recognition by NK cells, unravels a fundamental new viral immune evasion mechanism, and demonstrates how this forced the evolution of virus-specific activating MHC I–restricted Ly49 receptors.
Effect of Laser Beam Conditioning on Fabrication of Micro-Channels in Al2O3 Bio-ceramics Using Nd:YAG Laser
Authors: Abdo Basem M. A. , Al-Tamimi Abdulaziz , Al-Ahmari Abdulrahman , Alkhalefah Hisham
Published: May 2019

In the present study, laser micro-milling tests were carried out to fabricate micro-channels on Alumina bio-ceramics (Al2O3), using a Q-Switched 30W Nd:YAG pulsed laser. A systematic approach based on a full factorial Design of Experiment (DoE) has been successfully applied with the aim to detect which and how the key input laser process parameters affect the channel dimensional accuracy. The examined process parameters were the laser beam scanning speed, the pulse frequency and the pulse intensity. Optical microscope was used to analyze the channel geometries responses (i.e. channel's top width, bottom width, depth, and taper wall angle). Moreover, mathematical models for predicting the micro-channel geometries are successfully proposed for controlled micro-milling of micro-channels in Al2O3. Results reveal that, the change of scanning speed and laser intensity significantly affected the ablated channel’s geometries. Further it is observed that the channel depth and width increase linearly with increasing of laser intensity and decreasing of scanning speed and not much affected by changing of pulse frequency. Finally, the experimental results bear a good agreement with the proposed prediction models.
Obtaining Radiation-resistant Material by SHS Method
Authors: Kozhanova Maria , Kozhanov Anton , Golubenko Igor , Bikberdina Narkiza , Boronenko Marina
Published: May 2019

All The first results of obtaining radiation-resistant material by the SHS method are presented in the article. Synthesis of material based on the system Fe2O3-Al-Cr2O3-MoO3-Ti. The resulting material was irradiated with an electron beam of 1.8 MeV. The synthesis process was filmed by an action video camera. Fourier image analysis revealed the instability of combustion regimes and predicted the quality of reaction products. A comparative analysis of the microstructure of the samples before and after irradiation with electrons confirmed the results of the FFT. Despite the relatively low quality of the synthesis products, the embrittlement occurred at the absorbed dose of 70 Mrad. In the future, it is planned to improve the methodology for identifying unstable synthesis modes and adjusting the percentage ratio of the charge components.
Multi-Objective Scheduling Simulation of Adaptive Job Shop based on Modified SOMA Algorithm
Authors: Jiang Danding , Wang Mingwei , Zhao Ying , Jiang Tengyuan
Published: May 2019

In this paper, an effective modified Self-Organization Migrating Algorithm (SOMA) is proposed to solve multi-objective adaptive job shop scheduling with the criterion to minimize the processing cost, minimize makespan, minimize the total machine loads. The modified SOMA stresses the balance between global exploration and local exploitation by introduce adaptive step, and improved the population diversity in the process of individual migration by introduce quadratic interpolation, which effectively avoided the premature and improved the convergence of the SOMA. Finally, through the 4×6 job shop scheduling problem verify the performance of the modified SOMA algorithm, the computational results show that the proposed modified SOMA efficiently solves adaptive job shop scheduling.
Survey: The Evolution of the Usage of Augmented Reality in Industry 4.0
Authors: Gallala Abir , Hichri Bassem , Plapper Peter
Published: May 2019

The usage of Augmented Reality (AR) in industrial and modern manufacturing is more and more growing since the fourth industrial revolution. Using AR boost the digitization of the industrial production lines, gain time and money and improve maintenance tasks as well as the human-machine interaction. This paper is a literature review of the use of AR in industries including the use cases in different type of application such as design, simulation, maintenance, remote assistance, human-robot interaction and robot programming.
Performance evaluation of lime and microbial cementation in residual soil improvement
Authors: Umar M , Kassim K A , Zango M U , Muhammed A S
Published: May 2019

Microbially Induced Calcite Precipitation (MICP) is a technique that utilizes the concept of microbial involvements in calcium carbonate precipitation within the soil matrix structure. This leads to the cementation of the soil particles and consequently improving the strength and stiffness of the soil. In this study microbial carbonate precipitations were induced in tropical residual soil via urea hydrolysis. An isolate of urease active strain of Klebsiella pneumoniae UM123 was used to precipitates calcite into the soil with the aim of improving the engineering properties of the soil. Bacteria concentrations of 2.9 × 106 cfu/ml and 0.5 M cementation reagents concentrations were used to evaluate the strength and hydraulic conductivity of the soil. Treatment durations of 24, 36, 48 and 60 hours were used in the study. The results obtained indicated a general increase in the strength and reduction of hydraulic conductivity of the treated soil with the increase in treatment durations up to 48 hours. It was also revealed that the higher the amount of calcite precipitated the more the strength improvement and reduction of hydraulic conductivity. Appropriate percentage of lime that satisfied the initial consumption and fixation capacity of the soil sample was found to be 6%. Though, combination of MICP with lime does not significantly improve the strength at early stage of the treatment, it has substantially reduced the hydraulic conductivity of the treated residual soil particularly at the early curing period when lime alone increases the hydraulic conductivity.
Influence of tree type to suction development and the stability of slope
Authors: Bello N , Rees S W , Salisu S A
Published: May 2019

The overall aim of this research is to provide an assessment of suction development in a typical soil slope embankment. In particular, it demonstrated how different type of trees via their water-uptake demands enhances the stability of soil slope cutting, within a London clay formation. A total of 7 analyses were performed. The first analysis was performed to determine the saturated undrained Factor of Safety of the un-vegetated case study slope. A mature Oak tree was then superimposed on both the slope toe and its crest, and it was discovered that the presence of the tree at such locations increased the slope Factor of Safety by 2.15% and 2.00% respectively. A mature Horse Chestnut tree was then considered on the slope, and the tree enhanced the slope Factor of Safety by 2.01% and 1.94% on the toe and the crest respectively. The next analysis considered the effect of mature Poplar tree with a root zone deeper than both the Oak and the Chestnut; the Poplar tree increased the slope Factor of Safety by 12.65% and 2.77% at the toe and the crest respectively, indicating tree species with deeper root zone produced greater impacts than those with shallow root zone. Although 2% increase in Factor of Safety is not overlay significant but 12.7% is, therefore the findings indicate the magnitude at which trees with deep root zone enhanced the slope factor of safety albeit more on the slope toe.
Prediction of shear wave velocity in underground layers using Particle Swarm Optimization
Authors: Anak Upom Mark Ruben , Asmawisham Alel Mohd Nur , Ab Kadir Mariyana Aida , Yuzir Ali
Published: May 2019

Shear wave velocity (Vs) is considered a key soil parameter in the field of earthquake engineering. The time-averaged shear wave velocity in the upper 30 m (Vs30) layer of soil is used to classify seismic site class. In-situ Vs test is sometimes unsuitable to the project’s need due to financial reasons, noisy environment on site or simply the lack of expertise. This paper attempts to develop a global prediction model for Vs using Standard Penetration Resistance (Nspt), depth (z) and soil type (s

t)
as the independent parameters. Two approaches to modelling would be taken; a multi-linear regression (MLR) model and an ensemble (EN-PSO) model. The EN-PSO model attempts to improve upon the accuracy of the MLR model prediction ability using the ensemble learning method. A dataset was compiled from literatures for this paper. 5 Base models were developed: MLR, Random Forest (RFR), Support Vector Machine (SVR), Artificial Neural Network (ANN) and k-Nearest Neighbor (KNN) which are combined into an ensemble model named EN-PSO. The weights for EN-SPO was then calculated using Particle Swarm Optimization (PSO). The performance of each models were then compared and it was shown that EN-PSO was the best in terms of: MAE (Mean Absolute Error) = 22.085, MAPE (Mean Absolute Percentage Error) = 9.1 %, RMSE (Root Mean Square Error) = 31.741 and R2 Coefficient of Determination) = 0.895. In addition, it was also shown that the EN-PSO model was able to improve upon the performance of the MLR model, which the most accurate among the Base models. Comparisons were also made between EN-PSO and other suggested Universal Vs correlations and EN-PSO was shown to outperform the other correlation based on prediction using a modified Test set. Three new empirical correlations as alternative for the EN-PSO model was also presented.
Peat modification integrating Geopolymer and fly ash
Authors: Mohamed Jais I B , Abdullah N , Md Ali M A , Johar M A
Published: May 2019

Peat is known of its high compressibility, low shear strength, natural moisture content and long-term settlement. This indicates that peat is problematic, and it is necessary to improve the soil so that it can be used for supporting foundations. Fly ash is one of the source materials for geopolymer binders and available abundantly worldwide. It is considered as eco-friendly when it is used in the construction industry since it is a recycled material. A geopolymer mix known as Geopolymer Flexible Activator (GeoFlexA) and fly ash is used as an alternative solution to solve ground settlement issues related to soft soils. The purpose of this research is to modify peat by binding GeoFlexA and fly ash together. This research is carried out to determine the effect of GeoFlexA admixture and fly ash to the strength of peat. The index property tests include moisture content, organic content, fibre content, specific gravity and pH test only. Compaction test and Unconfined Compressive Test (UCT) is used to prepare samples and to analyse the strength respectively. The UCT was conducted after the samples were prepared in the mould and allowed to cure under 0, 7, 14, 28 and 56 days. Various percentages of fly ash used are 5%, 10%, 15% and 20% while a constant GeoFlexA admixture is used at 40% of the soil weight. The experimental results demonstrated that the compressive strength of the modified peat increases significantly with the fly ash content and curing time. These indicated that the mixture of GeoFlexA and fly ash can promote to an enhanced compressive strength of peat, hence, become a potential admixture for modifying peat.
Assessment of building vulnerability by integrating rapid visual screening and geographic information system: A case study of Ranau township
Authors: Mohamad I I , Mohd Yunus M Z , Harith N S H
Published: May 2019

The earthquake may cause many deaths and injuries and extensive property damage and dramatically change the geographic structure of the impacted area. Vulnerability in the context of building structure can be defined as inability to resist the earthquake loadings and unfortunately the majority of existing buildings in Ranau Township were built consequently without seismic consideration. The rapid development had increased the probability of building damages due to the earthquake activities that appeared around the area since. This study aims to identify, evaluate buildings and calculated vulnerability using the Rapid Visual Screening (RVS) method through the framework of Geographic Information System (GIS). The results of this study revealed that from 245 buildings, the damage level for 21 buildings were in grade 3, 11 buildings under grade 2 and other buildings in grade 1 i.e. heavy, moderate and little damages, respectively. After knowing the vulnerability level of buildings, the developer may do an early prevention to avoid further damages due to earthquakes in the future. This method can be used in moderate seismicity region such as Sabah as an early detection for building vulnerabilities.
Effect of rainfall on the compaction of dense-graded hot mix asphalt
Authors: Ismail S , Hassan N A , Yaacob H , Warid M N M , Mashros N , Mohamed A , Hassan S A , Azahar N M
Published: May 2019

Unpredictable tropical weather particularly rainfall can possibly interfere the compaction work of asphalt pavement. Heavy rainfall often leads the asphalt to cool and harden quickly and become difficult to compact. This study evaluates the effect of rainfall on the compaction properties of hot mix asphalt (HMA). A dense-graded mix of AC14 was prepared using 60/70 PEN bitumen and compacted at different temperatures. A handy steel roller was used to compact the slab samples with the size of 305 mm × 305 mm × 50 mm. The cooling rate and time available for compaction (TAC) were monitored using thermocouple under different levels of artificial rainfall and wind speed generated in the laboratory to simulate the wet conditions. The slabs were then cored at 100 mm diameter and tested for the volumetric properties. The result shows that environmental conditions and mix temperature determines the cooling rate and final density of the asphalt pavement. In addition, the TAC decreases as the compaction temperature reduces. Alternatively, working under light and moderate rainfall during the asphalt paving operation reasonably achieves the required degree of compaction (DOC). However, paving works under heavy rainfall reduce TAC, compactibility and density of the asphalt mat.
Modification of emulsified bitumen using Styrene-Butadiene Rubber (SBR)
Authors: Jin T H , Warid M N M , Idham M K , Hainin M R , Yaacob H , Hassan N A , Ismail C R , Afiqah R N
Published: May 2019

This paper evaluates the performance of using different percentage of styrene-butadiene rubber (SBR) in rapid-setting emulsion (RS-2K). The polymer modified bitumen emulsions were blended at various percentages of SBR, i.e. 5%, 7%, 9%, 11% and 13%. The investigation focused on the optimum percentage of SBR added into the polymer modified bitumen emulsion and the performance of the polymer modified bitumen emulsion. There are several laboratory tests involved such as penetration test, softening point test and dynamic shear rheometer test that were done in order to determine the physical and rheological properties of bitumen emulsion. Based on the results, it shows that the physical properties of the polymer modified bitumen improved compared to unmodified bitumen emulsion. For rheological properties, by adding the SBR in the bitumen emulsion, the rutting resistance of the bitumen emulsion is improved. From the isochronal curve, the polymer modified bitumen emulsion shows improvement in the complex modulus, G* as comparing to unmodified bitumen emulsion. The optimum percentage of the SBR is 13% as it shows better performance compared to other percentages.
Performance evaluation of asphalt micro surfacing – a review
Authors: Usman K R , Hainin M R , Idham M K , Warid M N M , Yaacob H , Hassan N A , Azman M , Puan O C
Published: May 2019

In spite the fact that micro surfacing receives accolades by researchers of being the most cost-effective, environmentally friendly, and functionally viable pavement preventive maintenance amongst the various asphalt surface treatments (AST). However, there has not been a universally standardised mix design, acceptable material type, compatible polymer-binder combination, laboratory-field correlational performance tests, and its field dependency performance indicators. The requirements set by the International Slurry Surfacing Association (ISSA), Malaysian Jabatan Kerja Raya (JKR-public works department) and American Society for Testing and Materials (ASTM) are stated to be guides. This study brings to fore the challenges, methodologies adopted and successes recorded towards solving the aforementioned concerns by various researches globally from existing literatures with emphasis on material-type effects, mix design methodology, serviceability/environmental performance, incorporation of industrial wastes and emulsion-polymer compatibility amongst others in micro surfacing. Hence, the contents of relevant published journal articles, theses, academic and industrial reports published within the last two decades (1979 - 2019) that met the selection criteria aforementioned were critiqued. Result indicated improvement in key pavement surface functional performance parameters as a function of enhanced polymer(s) used in improving desired performance, type of aggregate and its gradation, pre-treatment condition and ultimately emulsion type. However, there is a lack of total consensus on the mix design, even though polymers are unanimously agreed by researchers to improve performance. Future advances in micro surfacing should focus on the use of industrial wastes, synthetic material and especially by-products from industrial processes.