bluuebunny/crossref_metadata_2025 huggingface dataset:
DYNAMICS OF EPIDEMIOLOGICAL PARAMETERS OF TYPE 1 DIABETES MELLITUS IN CHILDREN IN THE REPUBLIC OF KARELIA
Authors: Varlamova T V , Dorchakova N V , Karapetyan T A
Published: May 2019

Type 1 diabetes mellitus is one of the most common autoimmune diseases in the world. The Republic of Karelia belongs to a group of regions with a high prevalence rate of type 1 diabetes mellitus (over 200 per 100,000 residents). In the last 20 years, type 1 diabetes incidence has increased 3.4 times, mostly due to the onset at an early age. The incidence rate of new cases of type 1 diabetes among children and adolescents does not show any clear linear dependence. Significant incidence occur every 4 or 5 years, which is most likely to be connected with an increase in the incidence of virus infection in these years. The primary incidence of type 1 diabetes mellitus among children per every 100 thousand of the child population is also higher in the Republic of Karelia compared to the Russian Federation. 17,4% children in Karelia have a genetic predisposition to type 1 diabetes mellitus (positive for HLA-DQB*0302 and/ or *02 and negative for the protective alleles *0602/03, *0301), which is lower than in Finland (23%).Genetic heterogeneity among ethnic populations in conjunction with environmental factors can determine the peculiarities of type 1 diabetes mellitus prevalence rate.
Nitrogen Washout and Venous Gas Emboli During Sustained vs. Discontinuous High-Altitude Exposures
Authors: Ånell Rickard , Grönkvist Mikael , Eiken Ola , Gennser Mikael
Published: May 2019

INTRODUCTION: The frequency of long-duration, high-altitude missions with fighter aircraft is increasing, which may increase the incidence of decompression sickness (DCS). The aim of the present study was to compare decompression stress during simulated sustained high-altitude
flying vs. high-altitude flying interrupted by periods of moderate or marked cabin pressure increase.METHODS: The level of venous gas emboli (VGE) was assessed from cardiac ultrasound images using the 5-degree Eftedal-Brubakk scale. Nitrogen washout/uptake was measured using a closed-circuit
rebreather. Eight men were investigated in three conditions: one 80-min continuous exposure to a simulated cabin altitude of A) 24,000 ft, or four 20-min exposures to 24,000 ft interspersed by three 20-min intervals at B) 20,000 ft or C) 900 ft.RESULTS: A and B induced marked and
persistent VGE, with peak bubble scores of [median (range)]: A: 2.5 (1–3); B: 3.5 (2–4). Peak VGE score was less in C [1.0 (1–2), P < 0.01]. Condition A exhibited an initially high and exponentially decaying rate of nitrogen washout. In C the washout rate was similar
in each period at 24,000 ft, and the nitrogen uptake rate was similar during each 900-ft exposure. B exhibited nitrogen washout during each period at 24,000 ft and the initial period at 20,000 ft, but on average no washout or uptake during the last period at 20,000 ft.DISCUSSION:
Intermittent reductions of cabin altitude from 24,000 to 20,000 ft do not appear to alleviate the DCS risk, presumably because the pressure increase is not sufficient to eliminate VGE. The nitrogen washout/uptake rate did not reflect DCS risk in the present exposures.Ånell R,
Grönkvist M, Eiken O, Gennser M. Nitrogen washout and venous gas emboli during sustained vs. discontinuous high-altitude exposures. Aerosp Med Hum Perform. 2019; 90(6):524–530.
Protein Content and Amino Acid Composition among Selected South African Sorghum Genotypes
Authors: Mofokeng M. A. , Shimelis H. , Tongoona P. , Laing M. D.
Published: May 2019

The presence of genetic diversity is essential for quality improvement to achieve balanced protein and amino acid levels in sorghum. The objective of this study was to determine the genetic diversity present among selected South African sorghum genotypes for protein and amino acid content and to select candidate lines for breeding or direct production. Fifty nine selected South African sorghum genotypes grown at two localities were analysed for crude protein content using near-infrared spectroscopy (NIR). Nineteen genotypes with high crude protein content from each location were selected and analysed for amino acid profiles using protein hydrolysates. The crude protein content of the genotypes varied from 7.69 to 16.18% across the two sites with a mean of 13.07%. The genotypes that had high crude protein content at both sites were Mammopane, AS16 M1, Macia-SA, AS19, Maseka-a-swere, and AS4. The genotype AS16cyc was the best candidate for high phenylananine content at 5.99%. Overall, the studied lines had great variability in their protein and amino acid profiles. Accessions with high protein content or amino acid values can be used in sorghum breeding programmes to increase grain nutritional quality.
Muhammed Ed-Destinâî’nin Âdâbü’l-Müftîn Adlı Risâlesi: İnceleme ve Tahkîk
Authors: Saylan Şenol
Published: May 2019

İftâ faaliyeti
ve usûlü ile ilgili hususlara ilk dönemlerde fürû-i fıkıh eserlerinin edebü’l-fetvâ
/ âdâbü’l-müftî adını taşıyan bölümlerinde yer verilmiş, ilerleyen süreçte
ise aynı adı taşıyan müstakil eserler kaleme alınmıştır.  Bu konudaki ilk müstakil eserler olarak İbnü’s-Salâh
eş-Şehrezûrî’nin Edebü’l-müftî ve’l-müsteftî’si ile İbn Hamdân’ın Sıfatü’l-müftî
ve’l-müsteftî adlı eseri zikredilebilir. Diğer mezheplere nispeten, Hanefî
mezhebinde fetvâ usûlünü konu edinen müstakil eserler daha geç bir dönemde
telif edilmiştir. Tespit edebildiğimiz kadarıyla ilk müstakil Hanefî fetvâ usûlü
eseri Muhammed ed-Destinâî’nin Âdâbü’l-müftîn adlı risâlesidir. IX.
(XV.) yüzyılın sonları veya X. (XVI.) yüzyılın başlarında kaleme alındığı
düşünülen bu eserin sadece tek nüshası tespit edilebilmiştir. Dört varaktan
müteşekkil risâlede, fetvâ kavramı ve türevleri, müftünün âdâbı ve şartları ile
müsteftînin âdabı konularına yer verilmektedir.

Bu makalede,
ilk müstakil Hanefî fetvâ usûlü eseri olan ve kaynaklarda hakkında fazla bilgi
bulunmayan Âdâbü’l-müftîn adlı risâle ile müellifi Muhammed ed-Destinâî
tanıtılacaktır. Ayrıca fetvâ usûlü literatürüne katkı düşüncesiyle bu muhtasar risâlenin
tahkikli metnine de yer verilecektir.
Fighting austerity: why after 80 years the General Theory is still relevant today
Authors: Marcuzzo Maria Cristina
Published: May 2019

In the aftermath of the 2007-8 crisis, the name of Keynes has again entered the list of economists to be read, whose ideas are to be taken seriously. After over twenty-five years of ostracism, spent praising the efficiency of free markets and running econometric tests to prove that economic policies are either ineffectual or even irrelevant, there has been an upsurge in the wave of references to Keynes in the media. Unfortunately, this has not been reflected in the academic scene, still dominated by the macroeconomics of anti- or pre-Keynesian inspiration that took hold between the 1970s and 1980s.
Macroeconomic flaws in the IMF’s ‘New’ Institutional view: The case of Brazil
Authors: Rafferty Devin Thomas
Published: May 2019

In 2012, the IMF issued its ‘New’ Institutional View which endorsed using capital controls for international financial stability, given certain prerequisites.  We argue this ‘View’ will be no more successful than the Fund’s other policy predecessors because it mandates solving capital flow-induced macroeconomic imbalances through ‘market-based’ adjustment measures rather than by using capital controls, thus relegating the latter to a secondary role.  To present our argument, we use Brazil’s recent history as a proxy for the IMF’s current platform.  This is because, despite explicitly not taking advice from the Fund, its actions have been, ironically, nonetheless consistent with the ‘New’ View’s updated prescriptions- which still culminated in crisis.  As a result, regardless of the revisions it made in the wake of the Great Financial Crisis, the Fund’s new stance is incapable of averting and stabilizing a crisis; indeed, the case of Brazil suggests it is instead a recipe for creating and amplifying financial macroeconomic fragility.
Fiscal policy rules in a stock-flow consistent model
Authors: Kappes Sylvio Antonio , Milan Marcelo
Published: May 2019

The present paper analyzes four fiscal policy rules in a Stock-Flow Consistent model. The rules are: (i) government expenditures as a fixed proportion of GDP; (ii) government deficit as a fixed proportion of GDP; (iii) government debt as a fixed proportion of GDP; and (iv) a balanced budget. Then the economic trends implied by each rule are analyzed, and they are all compared. Some of the main findings can be summarized as follows: the more expansionist (or less contractionist) rules present higher growth rates, as expected; there is an inverse relationship between government debt and private debt, with the former being higher under the first rule, and lower in the balanced budget rule, the opposite happening in the case of private debt. Finally, considering enterprises’ profitability, we conclude that the best fiscal rule for firms is the first one, and, for the banking sector, also not surprisingly, it is the balanced budget rule.
The internationalization of local currencies of emerging countries: the experience of the Mexican peso and the Chinese renminbi
Authors: Levy Noemi
Published: May 2019

Globalization introduced private and structural endogenous money (private monetary debts) as the main instrument of financial capital mobilization in the international financial system. A main consequence of this feature was the internalization of emerging economies currencies unfolding two successful experiences: the foreign exchange transactions related to the Mexican peso and the Chinese renminbi. The former currency internationalized as a result of the institutional changes unfolded in the Mexican economy and it’s insertion to the North American region (NAFTA); while the latter stemmed from a government strategy to influence the worldwide economy as a result of its accelerated economic growth and increased importance in the world economy. In this paper are discussed three main themes:  the way in which emerging economies currencies internationalized; the insertion of these economies in the international market, and the divergent developments of successful currency internationalization.
Examination of Acacia-Tree Gasification Process Under Varying Operating Parameters
Authors: Bodnár István , Iski Patrik , Skribanek Ádám
Published: May 2019

This paper presents the thermokinetic modeling of the gasification process performed on the acacia-tree under varying operating circumstances and different humidity levels. Gasification does not produce flue gas, but due to imperfect burning, synthesis gas appears which is rich in flammable components (CO2 and H2). The chemical structure of this gas depends on the components of the fuel and the humidity level, but is also greatly affected by the technological parameters, such as pressure and temperature, as well as the air-ratio. The study shows the change of chemical composition, fuel value and the reaction efficiency as a function of varying gasification temperature and pressure. Rising temperature results in improved efficiency, while higher pressure worsens reaction efficiency. However, at higher temperature intervals, the effect of the pressure is neglectable.
Steady/Unsteady Flow Through Small Earthfill Dams
Authors: Botoș Marius Lucian , Kisfaludi-Bak Zsombor
Published: May 2019

Small earthfill dams, without permanent water storage, are simple operation constructions without any outlet operation or control systems, and which provide water storage in flood wave periods. From the seepage point of view, these simple constructions have a specific complex behavior. Even if generally the body of the dam can be considered to be homogeneous, infiltration through partially saturated materials is unsteady. The water level rapidly increases from the minimum to the maximum level as the water storage volume is relatively low.
Monitoring System of Rail Surface Crack Propagation
Authors: Nyikes Zoltán , Tokody Dániel , Kovács Tünde
Published: May 2019

Industrially produced rails can contain some inherent failures without evident damage. If a fracture propagates beyond a critical size, it can lead to breakage. The study of fracture mechanics suggests many different theories for detecting the fracture. Continuous monitoring of the rail surface state is necessary in order to assure uninterrupted and safe transportation.
Application Features of Ultrasonic Welding
Authors: Bagyinszki Gyula , Bitay Enikő
Published: May 2019

The technological advantages of ultrasonic welding: (no requirement for filler metal; use of small electrical transient resistance contacts; ability to weld thin materials to thick materials) results in a helium-solid weld seam; the computer configuration of the welding parameters can easily be solved; clean and safe workflow (no sparks, flame or smoke); can be integrated into the production line. This article deals with some of the additional application features of this welding process.
The Implementation of an Opencv-Based Traffic Sign Identifier Videoanalyst Software
Authors: Balázs Viktor , Szilágyi László , Apagyi Antal , Erdei Timotei István
Published: May 2019

Nowdays, accidents tend to happen because our attention is being split up by the ever-growing influx of information, losing the focus from the driving, traffic signs, and other signals. The consequences of these minor or major accidents weight down on our shoulders. During our project, we tried to eliminate, or help this issue, using present technology, improving upon that, trying to avoid these accidents. Our task consisted on implementing a software, that could identify traffic signs from any video streams.
Info-Communication Experts in The Defence Sector: Vocational Training Program
Authors: Farkas Tibor , Hronyecz Erika
Published: May 2019

Nowadays, international and national events clearly point out the need for cooperation between different defense organizations in crisis and emergency situations (disaster events, migration issues, and other emergencies) for successful tasks. The fundamental basis of this cooperation is always the command and control activity supported by modern technical equipment that ensures the coordinated implementation of tasks. The key, human element of info-communication support is the preparation and training of the successful professionals. In this paper, the authors intend to present the importance of vocational training.
Development of a Pressure Measuring Unit Based on a Thermal Conductivity Gauge and a Low-Cost Embedded Solution for Mid-Range Vacuum Applications
Authors: Fekete Albert-Zsombor , Jakab-Farkas László
Published: May 2019

This study presents the development of a pressure measuring unit based on a Pirani gauge and a dedicated embedded system, incorporating a simple, low-cost practical solution for significantly reducing the various measurement altering factors, such as drifts, offsets and set point drifts. This is achieved by eliminating the conventional differential analogue signal processing stage and replacing it with a high resolution analog to digital converter. Therefore the goal was to minimize the number of the electronic components whose operation is influenced by variations in ambient temperature. The main topics discussed in the paper include the presentation of the measuring circuit’s configuration, the development of a low-cost embedded system, the calibration method and the solution implemented for eliminating the platforms limitation regarding the precision of the different mathematical calculations.
Heat Transfer Modeling and Validation in the Case of Butt Welded Joints
Authors: Halász Gergely , Kuti János , Széll Károly
Published: May 2019

The aim of our work is to compare the results of a virtual model to measure heat transfer data for butt welded joints. The primary goal is to compare real-time measured temperature with the software simulated data. The virtual model is a copy of the real product, technically a virtual prototyping process is examined. Prior to any production process such as joining by butt welding, real process parameters are tested on the model and later by experiments. In the case of many parts, the joining process is a key technology, where knowledge of the thermal effects of welding on the microstructure in the heat affected zone and the joint are vital.
Workplace Noise Examination in a Laboratory (Case Study)
Authors: Kocsis Dénes
Published: May 2019

In this case study, the course and assessment of a work noise problem in a laboratory environment are described. Noise measurements are performed for the evaluation of workplace noise levels caused by the dominant sources at the site of the investigation. The results are evaluated according to the current Hungarian legislation, which is harmonized with the directives of the European Union. Based on the results noise protection interventions are shown to be required and proposals are described to solve the current situation.
About The Modernized Grinding Wheel Dressingdevice S Diamond-Pin Driving System by The Nilesgear Grinding Machines
Authors: Márton Loránd
Published: May 2019

This paper deals with criteria and conditions that must be fulfilled by a modern grinding wheel dressing system. Its main task is the correct drawing of the given profile. By this task, the diamond pin’s axis must close during the motion at a constant angle with the normal of the wheel’s surface. This study presents the build-up and the proposed control strategy of the dressing device. Two control methods were analysed and compared.
Finite Element Modeling of Upsetting Considering Heat Generation
Authors: Mihalovits Roland , Gonda Viktor , Széll Károly
Published: May 2019

In this article, a finite element modeling of the upsetting of a cylindrical workpiece is presented. In the modeling, the effects of friction, heat generation from deformation, and heat losses from conduction and convection are considered.
Bending-Testing of Arrows
Authors: Pécsi Levente , Pásztor Judit , Kakucs András
Published: May 2019

Archery is a tradition, a style of martial arts and a competitive sport, while at the same time being an art form. The equipment consists of a bow and arrows. The deflection of the arrow is a very important characteristic, one which has a decisive influence on how and if the arrow reaches the target. This has a tremendous impact on the performance of the archer in both competition and archery demonstrations. The quantification and measurement of arrow deflection is equally important to both manufacturers and archers. It is affected by the arrow’s static bending. In this paper the bend of the arrow shall be determined.
Chip Removal Specialities in Multi-Directional Turning
Authors: Ráczi Viktor , Sipos Sándor , Farkas Gabriella
Published: May 2019

For machining of increasingly complicated geometries, the longitudinal and transverse turning operations should be performed with a single tool. Leading manufacturing companies have developed a number of constructions. The world’s largest manufacturer has recently revolutionised turning by launching roughing and finishing tools. The roughing insert can work with “high feed turning” in four different directions of movement. This tool has a unique chip forming and removal, it forms a unique machined surface. This study gives an overview of the results achieved in this area.
Pruning Optimization over Threshold-Based Historical Continuous Query
Authors: Qin Jiwei , Ma Liangli , Liu Qing
Published: May 2019

With the increase in mobile location service applications, spatiotemporal queries over the trajectory data of moving objects have become a research hotspot, and continuous query is one of the key types of various spatiotemporal queries. In this paper, we study the sub-domain of the continuous query of moving objects, namely the pruning optimization over historical continuous query based on threshold. Firstly, for the problem that the processing cost of the Mindist-based pruning strategy is too large, a pruning strategy based on extended Minimum Bounding Rectangle overlap is proposed to optimize the processing overhead. Secondly, a best-first traversal algorithm based on E3DR-tree is proposed to ensure that an accurate pruning candidate set can be obtained with accessing as few index nodes as possible. Finally, experiments on real data sets prove that our method significantly outperforms other similar methods.
Real-Time Arm Gesture Recognition Using 3D Skeleton Joint Data
Authors: Paraskevopoulos Georgios , Spyrou Evaggelos , Sgouropoulos Dimitrios , Giannakopoulos Theodoros , Mylonas Phivos
Published: May 2019

In this paper we present an approach towards real-time hand gesture recognition using the Kinect sensor, investigating several machine learning techniques. We propose a novel approach for feature extraction, using measurements on joints of the extracted skeletons. The proposed features extract angles and displacements of skeleton joints, as the latter move into a 3D space. We define a set of gestures and construct a real-life data set. We train gesture classifiers under the assumptions that they shall be applied and evaluated to both known and unknown users. Experimental results with 11 classification approaches prove the effectiveness and the potential of our approach both with the proposed dataset and also compared to state-of-the-art research works.
The Efficiency of a Low Dose of Biochar in Enhancing the Aromaticity of Humic-Like Substance Extracted from Poultry Manure Compost
Authors: Jindo Keiji , Sánchez-Monedero Miguel A. , Matsumoto Kazuhiro , Sonoki Tomonori
Published: May 2019

Using biochar as a bulking agent in composting is gradually becoming popular for the minimization of nitrogen losses during the process and the improvement in compost quality. While a wide range of different biochar doses is applied, not much clear information was available about the optimum ratio. This study presents the impact of adding a low dose (2% v/v) of slow-pyrolysis oak biochar (Quercus serrate Murray), into poultry manure on the recalcitrant characteristic of humified organic matter. The influence in the chemical composition of humic-like substance was evaluated in poultry manure compost prepared with (PM+B) and without biochar (PM). The shift to slightly more stable chemical composition was shown in humic acid-like (HA) and fulvic acid-like (FA) extracted from PM+B compost, by increasing the proportion of aromatic carbon groups and thermal stability measured by thermogravimetry. We conclude that the addition of 2% biochar moderately enhances the recalcitrance of humified organic carbon and this could be feasible for the implementation of the biochar use in composting since only a small amount is required.
Biostimulant Application with a Tropical Plant Extract Enhances Corchorus olitorius Adaptation to Sub-Optimal Nutrient Regimens by Improving Physiological Parameters
Authors: Carillo Petronia , Colla Giuseppe , El-Nakhel Christophe , Bonini Paolo , D’Amelia Luisa , Dell’Aversana Emilia , Pannico Antonio , Giordano Maria , Sifola Maria , Kyriacou Marios , De Pascale Stefania , Rouphael Youssef
Published: May 2019

The emerging role of plant biostimulants in enhancing nutrient efficiency is important for maintaining soil fertility under sub-optimal nutrient regimens. We aimed to elucidate the morpho-physiological and biochemical effects as well as mineral composition changes of greenhouse jute (Corchorus olitorius L.) treated with a commercial vegetal-derived biostimulant from a tropical plant extract (PE; Auxym®, Italpollina, Rivoli Veronese, Italy). Plants were sprayed in weekly intervals with a solution containing 2 mL·L−1 PE. Jute plants were supplied with three nutrient solution concentrations: full-, half-, and quarter-strength. Decreasing macronutrient concentrations in the nutrient solution (NS), especially at quarter-strength, triggered a decrease in several morphological (plant height, leaf number, and dry biomass) and physiological (net CO2 assimilation rate (ACO2) and SPAD (Soil Plant Analysis Development) index) parameters. PE application triggered specific ameliorative effects in terms of fresh yield at both half- and quarter-strength nutrient solution (15.5% and 29.5%, respectively). This was associated with an enhancement in ACO2, SPAD index, and especially the nutritional status (high nitrate, K, and Mg contents, and low Na content). The foliar application of PE, strongly increased chlorophyll b content, enhancing jute plant adaptation to fluctuating light and therefore the efficiency of photosynthesis, positively affecting starch, soluble proteins, and total amino acids content but only when jute plants were irrigated with full-strength NS, compared to the respective control treatment. At lower nutrient strength, PE reprogrammed the nitrogen distribution, allowing its remobilization from glutamate, which was quantitatively the major amino acid under lower nutrient strength, but not from chlorophylls, thus maintaining efficient photosynthesis. We confirmed that PE Auxym® acts in a balanced manner on the main metabolic pathways of the plant, regulating the uptake and transport of mineral nutrients and protein synthesis, increasing the accumulation of essential amino acids under full nutritive solutions, and re-distributing nitrogen from amino acids to allow leaf growth and expansion even under sub-optimal nutrient conditions. Overall, the use of natural plant biostimulants may be a potential solution in low-input conditions, where environmental constraints and restricted use of fertilizers may affect potential crop productivity.
Analyzing Spatial Community Pattern of Network Traffic Flow and Its Variations across Time Based on Taxi GPS Trajectories
Authors: Yu Wenhao , Guan Menglin , Chen Zhanlong
Published: May 2019

The transport system is a critical component of the urban environment in terms of its connectivity, aggregation, and dynamic functions. The transport system can be considered a complex system due to the massive traffic flows generated by the spatial interactions between land uses. Benefiting from the recent development of location-aware sensing technologies, large volumes of traffic flow data (e.g., taxi trajectory data) have been increasingly collected in spatial databases, which provides new opportunities to interpret transport systems in cities. This paper aims to analyze network traffic flow from the perspective of the properties of spatial connectivity, spatial aggregation, and spatial dynamics. To this end, we propose a three level framework to mine intra-city vehicle trajectory data. More specifically, the first step was to construct the network traffic flow, with nodes and edges representing the partitioned regions and associated traffic flows, respectively. We then detected community structures of network traffic flow based on their structural and traffic volume properties. Finally, we analyzed the variations of those communities across time for the dynamic transport system. Through experiments in Beijing city, we found that the method is effective in interpreting the mechanisms of urban space, and can provide references for administrative divisions.
Optical 3-D Profilometry for Measuring Semiconductor Wafer Surfaces with Extremely Variant Reflectivities
Authors: Chen Liang-Chia , Duong Duc-Hieu , Chen Chin-Sheng
Published: May 2019

A new surface profilometry technique is proposed for profiling a wafer surface with both diffuse and specular reflective properties. Most moiré projection scanning techniques using triangulation principle work effectively on diffuse reflective surfaces, on which the reflected light beams are assumed to be well captured by optical sensors. In reality, this assumption is no longer valid when measuring a semiconductor wafer surface having both diffuse and specular reflectivities. To resolve the above problem, the proposed technique uses a dual optical sensing configuration by engaging two optical sensors at two different viewing angles, with one acquiring diffuse reflective light and the other detecting at the same time specular surface light for achieving simultaneous full-field surface profilometry. The deformed fringes measured by both sensors could be further transformed into a 3-D profile and merged seamlessly for full-field surface reconstruction. Several calibration targets and industrial parts were measured to evaluate the feasibility and accuracy of the developed technique. Experimental results showed that the technique can effectively detect diffuse and specular light with repeatability of one standard deviation below 0.3 µm on a specular surface and 2.0 µm on a diffuse wafer surface when the vertical measuring range reaches 1.0 mm. The present findings indicate that the proposed technique is effective for 3-D microscale surface profilometry in in-situ semiconductor automated optical inspection (AOI).
Modelling and Simulation of Pseudo-Noise Sequence-Based Underwater Acoustic OSDM Communication System
Authors: Liu Lanjun , Zhao Hao , Li Ming , Zhou Lin , Jin Jiucai , Zhang Jie , Lv Zhichao , Ren Hui , Mao Jicun
Published: May 2019

Orthogonal signal division multiplex (OSDM) is an emerging signal modulation technology which has a lower peak-to-average power ratio (PAPR) and a flexible subcarrier system architecture. Particularly, it can be seen as a bridge between the single-carrier modulation and the orthogonal frequency division multiplexing (OFDM) modulation in the frequency domain. Aiming at the development trend and demand of underwater acoustic hybrid and adaptive modulation communication technology, a pseudo-noise (PN) sequence-based underwater acoustic OSDM communication system is proposed in this paper. A data frame structure with PN sequence is designed to solve the multipath and Doppler effect of underwater acoustic channel. On the basis of the PN sequence, a compressive sensing method based on the orthogonal matching pursuit (OMP) algorithm and the minimum mean square error (MMSE) algorithm is designed for channel estimation and equalization. On the basis of the system construction, the relationship among the OSDM vector length M, the OSDM subcarrier number N, and the underwater acoustic channel length is further studied for adaptive modulation of underwater acoustic communication. Finally, the proposed system is verified by simulation. The OSDM system has lower and controllable PAPR. When the OSDM vector length M is bigger than the channel length, and the system subcarrier flexibility is guaranteed, the bit error rate (BER) of the OSDM system is lower than that of the OFDM system and the single-carrier system. The PN sequence-based compressive sensing channel estimation and equalization with the OMP and MMSE algorithms has a good performance to resist the multipath effect of underwater acoustic channel.
Weightage Effect during Back-Calculation of Rock-Mass Quality from the Installed Tunnel Support in Rock-Mass Rating and Tunneling Quality Index System
Authors: Kim Jonguk , Rehman Hafeezur , Ali Wahid , Naji Abdul Muntaqim , Yoo Hankyu
Published: May 2019

In extensively used empirical rock-mass classification systems, the rock-mass rating (RMR) and tunneling quality index (Q) system, rock-mass quality, and tunnel span are used for the selection of rock bolt length and spacing and shotcrete thickness. In both systems, the rock bolt spacing and shotcrete thickness selection are based on the same principle, which is used for the back-calculation of the rock-mass quality. For back-calculation, there is no criterion for the selection of rock-bolt-spacing-based rock-mass quality weightage and shotcrete thickness along with tunnel-span-based rock-mass quality weightage. To determine this weightage effect during the back-calculation, five weightage cases are selected, explained through example, and applied using published data. In the RMR system, the weightage effect is expressed in terms of the difference between the calculated and back-calculated rock-mass quality in the two versions of RMR. In the Q system, the weightage effect is presented in plots of stress reduction factor versus relative block size. The results show that the weightage effect during back-calculation not only depends on the difference in rock-bolt-spacing-based rock-mass quality and shotcrete along with tunnel-span-based rock-mass quality, but also on their corresponding values.
Effects of Varying Noise Levels and Lighting Levels on Multimodal Speech and Visual Gesture Interaction with Aerobots
Authors: Abioye Ayodeji Opeyemi , Prior Stephen D. , Saddington Peter , Ramchurn Sarvapali D.
Published: May 2019

This paper investigated the effects of varying noise levels and varying lighting levels on speech and gesture control command interfaces for aerobots. The aim was to determine the practical suitability of the multimodal combination of speech and visual gesture in human aerobotic interaction, by investigating the limits and feasibility of use of the individual components. In order to determine this, a custom multimodal speech and visual gesture interface was developed using CMU (Carnegie Mellon University) sphinx and OpenCV (Open source Computer Vision) libraries, respectively. An experiment study was designed to measure the individual effects of each of the two main components of speech and gesture, and 37 participants were recruited to participate in the experiment. The ambient noise level was varied from 55 dB to 85 dB. The ambient lighting level was varied from 10 Lux to 1400 Lux, under different lighting colour temperature mixtures of yellow (3500 K) and white (5500 K), and different background for capturing the finger gestures. The results of the experiment, which consisted of around 3108 speech utterance and 999 gesture quality observations, were presented and discussed. It was observed that speech recognition accuracy/success rate falls as noise levels rise, with 75 dB noise level being the aerobot’s practical application limit, as the speech control interaction becomes very unreliable due to poor recognition beyond this. It was concluded that multi-word speech commands were considered more reliable and effective than single-word speech commands. In addition, some speech command words (e.g., land) were more noise resistant than others (e.g., hover) at higher noise levels, due to their articulation. From the results of the gesture-lighting experiment, the effects of both lighting conditions and the environment background on the quality of gesture recognition, was almost insignificant, less than 0.5%. The implication of this is that other factors such as the gesture capture system design and technology (camera and computer hardware), type of gesture being captured (upper body, whole body, hand, fingers, or facial gestures), and the image processing technique (gesture classification algorithms), are more important in developing a successful gesture recognition system. Some further works were suggested based on the conclusions drawn from this findings which included using alternative ASR (Automatic Speech Recognition) speech models and developing more robust gesture recognition algorithm.
Measurement of Elastic Properties of Brittle Materials by Ultrasonic and Indentation Methods
Authors: Wu Shih-Jeh , Chin Pei-Chieh , Liu Hawking
Published: May 2019

The measurements of acoustic properties of three brittle materials i.e., ITO (alkaline earth boro-aluminosilicate) glass, bulk metallic glass (BMG) and nickel-based superalloy (CM247LC) are conducted in this work to obtain various properties. The elastic moduli of materials are derived from the results by simple acoustic speed-elasticity relationship and compared with the data obtained with nanoindentation. The difference between the Young’s modulus of ITO glass by ultrasonic and nanoindentation is 0.83%, a perfect match within range error. As for BMG, the difference (Young’s modulus) is 23.59%, and 5.11% for the CM247LC superalloys. The pulse-echo method proves to be reliable for homogeneous amorphous glass, however, the elastic moduli of metallic glass and CM247LC superalloy by ultrasonic are quite different from those by nanoindentation. The difference is large enough to cover the maximal error associated with the nanoindentation method. The relationship of acoustic speed and elastic constants must be reviewed in dealing with compound materials.
Monitoring the Joint Area of Composite Membrane Materials
Authors: Winger Hans , Döbrich Oliver , Saeed Hassan , Gereke Thomas , Nocke Andreas , Cherif Chokri
Published: May 2019

Textile membranes are suitable for a wide range of applications due to their user-adjustable properties, which can be modified based on both the textile reinforcement structure and the coating material. Complex dynamic loads are involved in typical usage scenarios for load-bearing components of textile architecture, e.g., unsupported convertible roofs of halls or stadiums, temporary buildings, large-volume consumable media storage and the main sail of sailing boats. It is generally known that particularly in the area of membrane joints, successive degradation of seam strength may occur. This paper addresses the realization of an in situ measurement system for textile surface formation in textile membranes, which is introduced locally in the area of the joining zone and is compatible with the materials as well as the ultrasonic welding process itself. These development efforts are supported by a numerical investigation in terms of the serviceability and residual load-carrying capacity of the joining zone and the textile membrane surface area.
Reconstruction of Photoacoustic Tomography Inside a Scattering Layer Using a Matrix Filtering Method
Authors: Rui Wei , Liu Zhipeng , Tao Chao , Liu Xiaojun
Published: May 2019

Photoacoustic (PA) tomography (PAT) has potential for use in brain imaging due to its rich optical contrast, high acoustic resolution in deep tissue, and good biosafety. However, the skull often poses challenges for transcranial brain imaging. The skull can cause severe distortion and attenuation of the phase and amplitude of PA waves, which leads to poor resolution, low contrast, and strong noise in the images. In this study, we propose an image reconstruction method to recover the PA image insider a skull-like scattering layer. This method reduces the scattering artifacts by combining a correlation matrix filter and a time reversal operator. Both numerical simulations and PA imaging experiments demonstrate that the proposed approach effectively improves the image quality with less speckle noise and better signal-to-noise ratio. The proposed method may improve the quality of PAT in a complex acoustic scattering environment, such as transcranial brain imaging.
Effect of Incorporating Waste Limestone Powder into Solid Waste Cemented Paste Backfill Material
Authors: Hu Jianhua , Ding Xiaotian , Ren Qifan , Luo Zhouquan , Jiang Quan
Published: May 2019

To effectively reuse waste limestone powder, which is a major solid waste around mines, we replaced limestone powder back into a part of cement in solid waste cemented paste backfill (SWCPB) and studied the parameters of pore structures. To optimize the pore microstructure characteristics of SWCPB in mines, two different components and grade tailings were selected. The samples were characterized by scanning electron microscopy (SEM) and nuclear magnetic resonance (NMR) to examine the pore properties and microstructure of SWCPB. The results showed that (1) at the later curing stage, with the optimization of pore characteristics and microstructure through the limestone powder admixture, the strength of SWCFB was guaranteed at a 20% replacement degree of cement. (2) Porosity, macropore proportion, and the average pore radius all negatively correlated with limestone powder content, which were reduced by 7.15%, 46.35%, and 16.37%, respectively. (3) Limestone powder as a crystal nucleus participated in the hydration reaction and was embedded into the product to enhance the strength.
Coupled Dual-Loop Optoelectronic Oscillator Based on Stimulated Brillouin Scattering
Authors: Fan Feng , Zhu Wenwu , Wang Jiabin , Hu Jingjing , Gu Yiying , Wu Zhenlin , Han Xiuyou , Zhao Mingshan
Published: May 2019

A tunable optoelectronic oscillator (TOEO) with coupled dual-loop (CDL) based on stimulated Brillouin scattering (SBS) is proposed. In our scheme, the CDL is constructed by cascading a dual-output Mach–Zehnder intensity modulator (DOMZM) and a single output Mach–Zehnder intensity modulator (MZM). One optical output of the DOMZM is directly injected to the MZM, and the other optical output of the DOMZM is transformed into microwave signals to modulate the MZM. The narrow gain spectrum of SBS is used to select the oscillation frequency and realize frequency tunability. By joining the CDL, we can not only increase side mode suppression ratio (SMSR) and decrease phase noise, but also improve stability of the TOEO. Experimental results show that microwave signals from 2 GHz to 18 GHz with the SMSR as high as 60 dB and the phase noise as low as −95 dBc/Hz at 10 kHz frequency offset are achieved. Furthermore, the frequency drift is less than 0.3 ppm and the power drift is lower than 0.2 dB at 10 GHz within 30 min in lab condition.
A Short Note on Integral Transformations and Conversion Formulas for Sequence Generating Functions
Authors: Schmidt Maxie D.
Published: May 2019

The purpose of this note is to provide an expository introduction to some more curious integral formulas and transformations involving generating functions. We seek to generalize these results and integral representations which effectively provide a mechanism for converting between a sequence’s ordinary and exponential generating function (OGF and EGF, respectively) and vice versa. The Laplace transform provides an integral formula for the EGF-to-OGF transformation, where the reverse OGF-to-EGF operation requires more careful integration techniques. We prove two variants of the OGF-to-EGF transformation integrals from the Hankel loop contour for the reciprocal gamma function and from Fourier series expansions of integral representations for the Hadamard product of two generating functions, respectively. We also suggest several generalizations of these integral formulas and provide new examples along the way.
A Data-Driven Machine Learning Approach for Corrosion Risk Assessment—A Comparative Study
Authors: Ossai Chinedu I.
Published: May 2019

Understanding the corrosion risk of a pipeline is vital for maintaining health, safety and the environment. This study implemented a data-driven machine learning approach that relied on Principal Component Analysis (PCA), Particle Swarm Optimization (PSO), Feed-Forward Artificial Neural Network (FFANN), Gradient Boosting Machine (GBM), Random Forest (RF) and Deep Neural Network (DNN) to estimate the corrosion defect depth growth of aged pipelines. By modifying the hyperparameters of the FFANN algorithm with PSO and using PCA to transform the operating variables of the pipelines, different Machine Learning (ML) models were developed and tested for the X52 grade of pipeline. A comparative analysis of the computational accuracy of the corrosion defect growth was estimated for the PCA transformed and non-transformed parametric values of the training data to know the influence of the PCA transformation on the accuracy of the models. The result of the analysis showed that the ML modelling with PCA transformed data has an accuracy that is 3.52 to 5.32 times better than those carried out without PCA transformation. Again, the PCA transformed GBM model was found to have the best modeling accuracy amongst the tested algorithms; hence, it was used for computing the future corrosion defect depth growth of the pipelines. This helped to compute the corrosion risks using the failure probabilities at different lifecycle phases of the asset. The excerpts from the results of this study indicate that my technique is vital for the prognostic health monitoring of pipelines because it will provide information for maintenance and inspection planning.
Network Contractility during Cytokinesis—From Molecular to Global Views
Authors: Leite Joana , Osorio Daniel Sampaio , Sobral Ana Filipa , Silva Ana Marta , Carvalho Ana Xavier
Published: May 2019

Cytokinesis is the last stage of cell division, which partitions the mother cell into two daughter cells. It requires the assembly and constriction of a contractile ring that consists of a filamentous contractile network of actin and myosin. Network contractility depends on network architecture, level of connectivity and myosin motor activity, but how exactly is the contractile ring network organized or interconnected and how much it depends on motor activity remains unclear. Moreover, the contractile ring is not an isolated entity; rather, it is integrated into the surrounding cortex. Therefore, the mechanical properties of the cell cortex and cortical behaviors are expected to impact contractile ring functioning. Due to the complexity of the process, experimental approaches have been coupled to theoretical modeling in order to advance its global understanding. While earlier coarse-grained descriptions attempted to provide an integrated view of the process, recent models have mostly focused on understanding the behavior of an isolated contractile ring. Here we provide an overview of the organization and dynamics of the actomyosin network during cytokinesis and discuss existing theoretical models in light of cortical behaviors and experimental evidence from several systems. Our view on what is missing in current models and should be tested in the future is provided.
Drug Delivery Systems: Study of Inclusion Complex Formation between Methylxanthines and Cyclodextrins and Their Thermodynamic and Transport Properties
Authors: Santos Cecília I. A. V. , Ribeiro Ana C. F. , Esteso Miguel A.
Published: May 2019

This paper presents an analysis of the molecular mechanisms involved in the formation of inclusion complexes together with some structural interpretation of drug–carrier molecule interactions in aqueous multicomponent systems comprising methylxanthines and cyclodextrins. The determination of apparent partial molar volumes ( φ V ) from experimental density measurements, both for binary and ternary aqueous solutions of cyclodextrins and methylxanthines, was performed at low concentration range to be consistent with their therapeutic uses in the drug-releasing field. The estimation of the equilibrium constant for inclusion complexes of 1:1 stoichiometry was done through the mathematical modelling of this apparent molar property. The examination of the volume changes offered information about the driving forces for the insertion of the xanthine into the cyclodextrin molecule. The analysis on the volumes of transfer, Δ φ V , c , and the viscosity B-coefficients of transfer, ΔB, for the xanthine from water to the different aqueous solutions of cyclodextrin allowed evaluating the possible interactions between aqueous solutes and/or solute–solvent interactions occurring in the solution. Mutual diffusion coefficients for binary, and ternary mixtures composed by xanthine, cyclodextrin, and water were measured with the Taylor dispersion technique. The behavior diffusion of these multicomponent systems and the coupled flows occurring in the solution were analyzed in order to understand the probable interactions between cyclodextrin–xanthine by estimating their association constants and leading to clearer insight of these systems structure. The measurements were performed at the standard (298.15 ± 0.01) K and physiological (310.15 ± 0.01) K temperatures.