bluuebunny/crossref_metadata_2025 huggingface dataset:
Closing the Phenotyping Gap: High Resolution UAV Time Series for Soybean Growth Analysis Provides Objective Data from Field Trials
Authors: Borra-Serrano Irene , De Swaef Tom , Quataert Paul , Aper Jonas , Saleem Aamir , Saeys Wouter , Somers Ben , Roldán-Ruiz Isabel , Lootens Peter
Published: May 2020

Close remote sensing approaches can be used for high throughput on-field phenotyping in the context of plant breeding and biological research. Data on canopy cover (CC) and canopy height (CH) and their temporal changes throughout the growing season can yield information about crop growth and performance. In the present study, sigmoid models were fitted to multi-temporal CC and CH data obtained using RGB imagery captured with a drone for a broad set of soybean genotypes. The Gompertz and Beta functions were used to fit CC and CH data, respectively. Overall, 90.4% fits for CC and 99.4% fits for CH reached an adjusted R2 > 0.70, demonstrating good performance of the models chosen. Using these growth curves, parameters including maximum absolute growth rate, early vigor, maximum height, and senescence were calculated for a collection of soybean genotypes. This information was also used to estimate seed yield and maturity (R8 stage) (adjusted R2 = 0.51 and 0.82). Combinations of parameter values were tested to identify genotypes with interesting traits. An integrative approach of fitting a curve to a multi-temporal dataset resulted in biologically interpretable parameters that were informative for relevant traits.
SMOS Third Mission Reprocessing after 10 Years in Orbit
Authors: Oliva Roger , Martín-Neira Manuel , Corbella Ignasi , Closa Josep , Zurita Albert , Cabot François , Khazaal Ali , Richaume Philippe , Kainulainen Juha , Barbosa Jose , Lopes Gonçalo , Tenerelli Joseph , Díez-García Raul , González-Gambau Veronica , Crapolicchio Raffaele
Published: May 2020

After more than 10 years in orbit, the SMOS team has started a new reprocessing campaign for the SMOS measurements, which includes the changes in calibration and image reconstruction that have been made to the Level 1 Operational Processor (L1OP) during the past few years. The current L1 processor, version v620, was used for the second mission reprocessing in 2014. The new version, v724, is the one run in the third mission reprocessing and will become the new operational processor. The present paper explains the major changes applied and analyses the quality of the data with different metrics. The results have been obtained with numerous individual tests that have confirmed the benefits of the evolutions and an end-to-end processing campaign involving three years of data used to assess the improvements of the SMOS measurements quantitatively.
Open Earth Observations for Sustainable Urban Development
Authors: Prakash Mihir , Ramage Steven , Kavvada Argyro , Goodman Seth
Published: May 2020

Our cities are the frontier where the battle to achieve the global sustainable development agenda over the next decade would be won or lost. This requires an evidence-based approach to local decision-making and resource allocation, which can only be possible if current gaps in urban data are bridged. Earth observation (EO) offers opportunities to provide timely, spatially disaggregated information that supports this need. Spatially disaggregated information, which is also demanded by cities for forward planning and land management, has not received much attention largely due to three reasons: (i) the cost of generating this data through traditional methods remains high; (ii) the technical capacity in geospatial sciences in many countries is low due to a shortage of skilled professionals who can find and/or process available data; and (iii) the inertia against disturbing routine workflows and adopting new practices that are not imposed through legal requirements at the country level. In support of overcoming the first two challenges, this paper discusses the importance of EO data in the urban context, how it is already being used by some city leaders for decision making, and what other applications it offers in the realm of urban sustainability monitoring. It also illustrates how the EO community, via the Group on Earth Observations (GEO) and its members, is working to make this data more easily accessible and lower barriers of use by policymakers and urban practitioners that are interested in implementing and tracking sustainable development in their jurisdictions. The paper concludes by shining a light on the challenges that remain to be overcome for better adoption of EO data for urban decision making through better communication between the two groups, to enable a more effective alignment of the produced data with the users’ needs.
A Neural Network-Based Rain Effect Correction Method for HY-2A Scatterometer Backscatter Measurements
Authors: Xie Xuetong , Wang Jing , Lin Mingsen
Published: May 2020

The backscattering coefficients measured by Ku-band scatterometers are strongly affected by rainfall, resulting in a systematic error in sea surface wind field retrieval. In rainy conditions, the radar signals are subject to absorption by the raindrops in their round-trip propagation through the atmosphere, while the backscatter of raindrops raises the echo energy. In addition, raindrops give rise to roughness by impinging the ocean surface, resulting in an increase in the echo energy measured by a scatterometer. Under moderate wind conditions, the comprehensive impact of rainfall causes the wind speeds retrieved by the scatterometer to be higher than their actual values. The HY-2A scatterometer is a Ku-band, pencil-beam, conically scanning scatterometer. To correct the systematic error of the HY-2A scatterometer measurement in rainy conditions, a neural network model is proposed according to the characteristics of the backscatter coefficients measured by the HY-2A scatterometer in the presence of rain. With the neural network, the wind fields of the European Centre for Medium-range Weather Forecasts (ECMWF) reanalysis data were used as the reference to correct the deviation in backscatter coefficients measured by the HY-2A scatterometer in rainy conditions, and the accuracy in wind speeds retrieved using the corrected backscatter coefficients was significantly improved. Compared with the cases of wind retrieval without rain effect correction, the wind speeds retrieved from the corrected backscatter coefficients by the neural network show a much lower systematic deviation, which indicates that the neural network can effectively remove the systematic deviation in the backscatter coefficients and the retrieved wind speeds caused by rain.
Can Low-Cost Unmanned Aerial Systems Describe the Forage Quality Heterogeneity? Insight from a Timothy Pasture Case Study in Southern Belgium
Authors: Michez Adrien , Philippe Lejeune , David Knoden , Sébastien Cremer , Christian Decamps , Bindelle Jérôme
Published: May 2020

Applied to grazing management, unmanned aerial systems (UASs) allow for the monitoring of vegetation at the level of each individual on the pasture while covering a significant area (>10 ha per flight). Few studies have investigated the use of UASs to describe the forage quality in terms of nutritive value or chemical composition, while these parameters are essential in supporting the productive functions of animals and are known to change in space (i.e., sward species and structure) and time (i.e., sward phenology). Despite interest, these parameters are scarcely assessed by practitioners as they usually require important laboratory analyses. In this context, our study investigates the potential of off-the-shelf UAS systems in modeling essential parameters of pasture productivity in a precision livestock context: sward height, biomass, and forage quality. In order to develop a solution which is easily reproducible for the research community, we chose to avoid expensive solutions such as UAS LiDAR (light detection and ranging) or hyperspectral sensors, as well as comparing several UAS acquisition strategies (sensors and view angles). Despite their low cost, all tested strategies provide accurate height, biomass, and forage quality estimates of timothy pastures. Considering globally the three groups of parameters, the UAS strategy using the DJI Phantom 4 pro (Nadir view angle) provides the most satisfactory results. The UAS survey using the DJI Phantom 4 pro (Nadir view angle) provided R2 values of 0.48, 0.72, and 0.7, respectively, for individual sward height measurements, mean sward height, and sward biomass. In terms of forage quality modeling, this UAS survey strategy provides R2 values ranging from 0.33 (Acid Detergent Lignin) to 0.85 (fodder units for dairy and beef cattle and fermentable organic matter). Even if their performances are of lower order than state-of-art techniques such as LiDAR for sward height or hyperspectral sensors (for biomass and forage quality modeling), the important trade-off in terms of costs between UAS LiDAR (>100,000 €) or hyperspectral sensors (>50,000 €) promotes the use of such low-cost UAS solutions. This is particularly true for sward height modeling and biomass monitoring, where our low-cost solutions provide more accurate results than state-of-the-art field approaches, such as rising plate meters, with a broader extent and a finer spatial grain.
Enhancing Methods for Under-Canopy Unmanned Aircraft System Based Photogrammetry in Complex Forests for Tree Diameter Measurement
Authors: Krisanski Sean , Taskhiri Mohammad , Turner Paul
Published: May 2020

The application of Unmanned Aircraft Systems (UAS) beneath the forest canopy provides a potentially valuable alternative to ground-based measurement techniques in areas of dense canopy cover and undergrowth. This research presents results from a study of a consumer-grade UAS flown under the forest canopy in challenging forest and terrain conditions. This UAS was deployed to assess under-canopy UAS photogrammetry as an alternative to field measurements for obtaining stem diameters as well as ultra-high-resolution (~400,000 points/m2) 3D models of forest study sites. There were 378 tape-based diameter measurements collected from 99 stems in a native, unmanaged eucalyptus pulchella forest with mixed understory conditions and steep terrain. These measurements were used as a baseline to evaluate the accuracy of diameter measurements from under-canopy UAS-based photogrammetric point clouds. The diameter measurement accuracy was evaluated without the influence of a digital terrain model using an innovative tape-based method. A practical and detailed methodology is presented for the creation of these point clouds. Lastly, a metric called the Circumferential Completeness Index (CCI) was defined to address the absence of a clearly defined measure of point coverage when measuring stem diameters from forest point clouds. The measurement of the mean CCI is suggested for use in future studies to enable a consistent comparison of the coverage of forest point clouds using different sensors, point densities, trajectories, and methodologies. It was found that root-mean-squared-errors of diameter measurements were 0.011 m in Site 1 and 0.021 m in the more challenging Site 2. The point clouds in this study had a mean validated CCI of 0.78 for Site 1 and 0.7 for Site 2, with a mean unvalidated CCI of 0.86 for Site 1 and 0.89 for Site 2. The results in this study demonstrate that under-canopy UAS photogrammetry shows promise in becoming a practical alternative to traditional field measurements, however, these results are currently reliant upon the operator’s knowledge of photogrammetry and his/her ability to fly manually in object-rich environments. Future work should pursue solutions to autonomous operation, more complete point clouds, and a method for providing scale to point clouds when global navigation satellite systems are unavailable.
To Blend or Not to Blend? A Framework for Nationwide Landsat–MODIS Data Selection for Crop Yield Prediction
Authors: Chen Yang , McVicar Tim R. , Donohue Randall J. , Garg Nikhil , Waldner François , Ota Noboru , Li Lingtao , Lawes Roger
Published: May 2020

The onus for monitoring crop growth from space is its ability to be applied anytime and anywhere, to produce crop yield estimates that are consistent at both the subfield scale for farming management strategies and the country level for national crop yield assessment. Historically, the requirements for satellites to successfully monitor crop growth and yield differed depending on the extent of the area being monitored. Diverging imaging capabilities can be reconciled by blending images from high-temporal-frequency (HTF) and high-spatial-resolution (HSR) sensors to produce images that possess both HTF and HSR characteristics across large areas. We evaluated the relative performance of Moderate Resolution Imaging Spectroradiometer (MODIS), Landsat, and blended imagery for crop yield estimates (2009–2015) using a carbon-turnover yield model deployed across the Australian cropping area. Based on the fraction of missing Landsat observations, we further developed a parsimonious framework to inform when and where blending is beneficial for nationwide crop yield prediction at a finer scale (i.e., the 25-m pixel resolution). Landsat provided the best yield predictions when no observations were missing, which occurred in 17% of the cropping area of Australia. Blending was preferred when <42% of Landsat observations were missing, which occurred in 33% of the cropping area of Australia. MODIS produced a lower prediction error when ≥42% of the Landsat images were missing (~50% of the cropping area). By identifying when and where blending outperforms predictions from either Landsat or MODIS, the proposed framework enables more accurate monitoring of biophysical processes and yields, while keeping computational costs low.
Assessing Typhoon-Induced Canopy Damage Using Vegetation Indices in the Fushan Experimental Forest, Taiwan
Authors: Peereman Jonathan , Hogan James Aaron , Lin Teng-Chiu
Published: May 2020

Cyclonic windstorms profoundly affect forest structure and function throughout the tropics and subtropics. Remote sensing techniques and vegetation indices (VIs) have improved our ability to characterize cyclone impacts over broad spatial scales. Although VIs are useful for understanding changes in forest cover, their consistency on detecting changes in vegetation cover is not well understood. A better understanding of the similarities and differences in commonly used VIs across disturbance events and forest types is needed to reconcile the results from different studies. Using Landsat imagery, we analyzed the change between pre- and post-typhoon VI values (ΔVIs) of four VIs for five typhoons (local name of cyclones in the North Pacific) that affected the Fushan Experimental Forest of Taiwan. We found that typhoons varied in their effect on forest canopy cover even when they had comparable trajectories, wind speeds, and rainfall. Most VIs measured a decrease in forest cover following typhoons, ranging from −1.18% to −19.87%; however, the direction of ΔVI–topography relationships varied among events. All typhoons significantly increased vegetation heterogeneity, and ΔVI was negatively related to pre-typhoon VI across all typhoons. Four of the five typhoons showed that more frequently affected sites had greater VI decreases. VIs ranged in their sensitivity to detect typhoon-induced changes in canopy coverage, and no single VI was most sensitive across all typhoons. Therefore, we recommend using VIs in combination—for example Normalized Difference Infrared Index (NDII) and Enhanced Vegetation Index (EVI), when comparing cyclone-disturbance-induced changes in vegetation cover among disturbances and across forests.
Numerical Modeling and Investigation of Amperometric Biosensors with Perforated Membranes
Authors: Hashem Zadeh Seyed Mohsen , Heidarshenas Mohammadhosein , Ghalambaz Mohammad , Noghrehabadi Aminreza , Saffari Pour Mohsen
Published: May 2020

The present paper aims to investigate the influence of perforated membrane geometry on the performance of biosensors. For this purpose, a 2-D axisymmetric model of an amperometric biosensor is analyzed. The governing equations describing the reaction-diffusion equations containing a nonlinear term related to the Michaelis–Menten kinetics of the enzymatic reaction are introduced. The partial differential governing equations, along with the boundary conditions, are first non-dimensionalized by using appropriate dimensionless variables and then solved in a non-uniform unstructured grid by employing the Galerkin Finite Element Method. To examine the impact of the hole-geometry of the perforated membrane, seven different geometries—including cylindrical, upward circular cone, downward circular cone, upward paraboloid, downward paraboloid, upward concave paraboloid, and downward concave paraboloid—are studied. Moreover, the effects of the perforation level of the perforated membrane, the filling level of the enzyme on the transient and steady-state current of the biosensor, and the half-time response are presented. The results of the simulations show that the transient and steady-state current of the biosensor are affected by the geometry dramatically. Thus, the sensitivity of the biosensor can be influenced by different hole-geometries. The minimum and maximum output current can be obtained from the cylindrical and upward concave paraboloid holes. On the other hand, the least half-time response of the biosensor can be obtained in the cylindrical geometry.
Optimal Central Frequency for Non-Contact Vital Sign Detection Using Monocycle UWB Radar
Authors: Rittiplang Artit , Phasukkit Pattarapong , Orankitanun Teerapong
Published: May 2020

Ultra-wideband (UWB) radar has become a critical remote-sensing tool for non-contact vital sign detection such as emergency rescues, securities, and biomedicines. Theoretically, the magnitude of the received reflected signal is dependent on the central frequency of mono-pulse waveform used as the transmitted signal. The research is based on the hypothesis that the stronger the received reflected signals, the greater the detectability of life signals. In this paper, we derive a new formula to compute the optimal central frequency to obtain as maximum received reflect signal as possible over the frequency up to the lower range of Ka-band. The proposed formula can be applicable in the optimization of hardware for UWB life detection and non-contact monitoring of vital signs. Furthermore, the vital sign detection results obtained by the UWB radar over a range of central frequency have been compared to those of the former continuous (CW) radar to provide additional information regarding the advantages and disadvantages of each radar.
Data Improvement Model Based on ECG Biometric for User Authentication and Identification
Authors: Barros Alex , Resque Paulo , Almeida João , Mota Renato , Oliveira Helder , Rosário Denis , Cerqueira Eduardo
Published: May 2020

The rapid spread of wearable technologies has motivated the collection of a variety of signals, such as pulse rate, electrocardiogram (ECG), electroencephalogram (EEG), and others. As those devices are used to do so many tasks and store a significant amount of personal data, the concern of how our data can be exposed starts to gain attention as the wearable devices can become an attack vector or a security breach. In this context, biometric also has expanded its use to meet new security requirements of authentication demanded by online applications, and it has been used in identification systems by a large number of people. Existing works on ECG for user authentication do not consider a population size close to a real application. Finding real data that has a big number of people ECG’s data is a challenge. This work investigates a set of steps that can improve the results when working with a higher number of target classes in a biometric identification scenario. These steps, such as increasing the number of examples, removing outliers, and including a few additional features, are proven to increase the performance in a large data set. We propose a data improvement model for ECG biometric identification (user identification based on electrocardiogram—DETECT), which improves the performance of the biometric system considering a greater number of subjects, which is closer to a security system in the real world. The DETECT model increases precision from 78% to 92% within 1500 subjects, and from 90% to 95% within 100 subjects. Moreover, good False Rejection Rate (i.e., 0.064003) and False Acceptance Rate (i.e., 0.000033) were demonstrated. We designed our proposed method over PhysioNet Computing in Cardiology 2018 database.
A Scalable Architecture for the Dynamic Deployment of Multimodal Learning Analytics Applications in Smart Classrooms
Authors: Huertas Celdrán Alberto , Ruipérez-Valiente José A. , García Clemente Félix J. , Rodríguez-Triana María Jesús , Shankar Shashi Kant , Martínez Pérez Gregorio
Published: May 2020

The smart classrooms of the future will use different software, devices and wearables as an integral part of the learning process. These educational applications generate a large amount of data from different sources. The area of Multimodal Learning Analytics (MMLA) explores the affordances of processing these heterogeneous data to understand and improve both learning and the context where it occurs. However, a review of different MMLA studies highlighted that ad-hoc and rigid architectures cannot be scaled up to real contexts. In this work, we propose a novel MMLA architecture that builds on software-defined networks and network function virtualization principles. We exemplify how this architecture can solve some of the detected challenges to deploy, dismantle and reconfigure the MMLA applications in a scalable way. Additionally, through some experiments, we demonstrate the feasibility and performance of our architecture when different classroom devices are reconfigured with diverse learning tools. These findings and the proposed architecture can be useful for other researchers in the area of MMLA and educational technologies envisioning the future of smart classrooms. Future work should aim to deploy this architecture in real educational scenarios with MMLA applications.
New Instrumented Trolleys and A Procedure for Automatic 3D Optical Inspection of Railways
Authors: Valigi Maria Cristina , Logozzo Silvia , Meli Enrico , Rindi Andrea
Published: May 2020

This paper focuses on new instrumented trolleys, allowing automated 3D inspection of railway infrastructures, using optical scanning principles and devices for defects and damage evaluation. Inspection of rolling components is crucial for wear evaluation and to schedule maintenance interventions to assure safety. Currently, inspection trolleys are mainly instrumented with 2D contact or optical sensors. The application of 3D non-contact digitizers proposed in this paper allows for a quick and more complete monitoring of the health conditions of railways, also in combination with a proper procedure for automatic 3D inspection. The results of the experimental tests using 3D portable optical scanners on railways are compared with results obtained by a trolley instrumented with 2D contact sensors. The results demonstrate the effectiveness of the trolleys mounting 3D handheld optical digitizers with proper automated software inspection procedures.
The Wearable Co-Design Domino: A User-Centered Methodology to Co-Design and Co-Evaluate Wearables
Authors: Francés Morcillo Leire , Morer-Camo Paz , Isabel Rodriguez Ferradas María , Cazón Martín Aitor
Published: May 2020

This paper presents a user-centered methodology to co-design and co-evaluate wearables that has been developed following a research-through design methodology. It has been based on the principles of human–computer interaction and on an empirical case entitled “Design and Development of a Low-Cost Wearable Glove to Track Forces Exerted by Workers in Car Assembly Lines” published in Sensors. Insights from both studies have been used to develop the wearable co-design domino presented in this study. The methodology consists of different design stages composed of an ideation stage, digital service development and test stages, hardware development and test stage, and a final test stage. The main conclusions state that it is necessary to maintain a close relationship between human factors and technical factors when designing wearable. Additionally, through the several studies, it has been concluded that there is need of different field experts that should co-design and co-evaluate wearable iteratively and involving users from the beginning of the process.
Shaping up the Future Spatial Plans for Urban Areas in Pakistan
Authors: Hussnain Muhammad Qadeer ul , Waheed Abdul , Wakil Khydija , Pettit Christopher James , Hussain Ejaz , Naeem Malik Asghar , Anjum Ghulam Abbas
Published: May 2020

Since 2007, more than fifty percent of our planet’s population is living in urban areas. In the coming decade, the rate of urbanization will be fastest in Asia and Africa. Within South Asian countries, urbanization has attained its fastest pace in Pakistan. Urban planners and agencies in Pakistan have tried various spatial plan making solutions to manage urban areas, but none have given the desired results. After a 20% increase in declared urban areas within last two decades, urban planners and policy makers are looking for a more innovative and realistic spatial planning solution, which could adjust to the uncertainties and complexities of real world. This research uses a mixed method approach comprising a two phased survey of professional planners, analyzed through the selective lexicon approach to document planners’ opinions about the reasons behind the poor performance and conformance of spatial plans. This study documents the planners’ understanding of the contemporary concept of ‘scenario planning’. To explore the solution, this paper presents a semi-systematic review of the literature on the application of the ‘scenario method in urban spatial planning’. As a result of this research, a comprehensive digital inventory of all spatial plans ever made in Pakistan has been developed. It has been found that 83% of the urban settlements in Pakistan are growing without a spatial plan and require immediate attention. Furthermore, in terms of the plan making process, twenty-seven major factors contributing to the failure of past plans have been identified and categorized under seven distinct plan making stages. Finally, a new process of spatial plan-making has been proposed, which is the fusion of scenario planning and the traditional plan-making process, backed by digital planning tools. In an era of smart cities and digitization, it is expected that the advancements in scenarios planning, coupled with a new data portal, will assist in addressing the implementation gap in practice, and result in more comprehensive data-driven spatial plans.
The Future of Yak Farming from the Perspective of Yak Herders and Livestock Professionals
Authors: Dorji Nedup , Derks Marjolein , Groot Koerkamp Peter W.G. , Bokkers Eddie A.M.
Published: May 2020

The declining number of yak farming families is perceived as a socio-political and economic concern in Bhutan. However, there is limited understanding of what influences herders’ plans and decisions on yak farming. We studied factors determining future perspectives of yak farming by interviewing yak herders and livestock professionals. We analysed relationships between herders’ characteristics and level of concerns, and future plans related to yak farming. Furthermore, relationships between level of concern and future plans were analysed. Most of the herder characteristics did not influence their future plans with yak farming. Age and level of perceived concern of the herders was associated with their wish for their children to continue yak farming in the future. Nevertheless, they expect that the number of yak farming families will decline in the next ten years. Additionally, most of the livestock professionals believe that the number of yak farming families will decline in the future. No differences were observed between the aggregated score of concern of herders and livestock professionals. The most important factors threatening the future of yak farming in Bhutan according to herders and livestock professionals are forage shortage, predation and no successor to take up yak farming.
Hyperspectral Inversion of Petroleum Hydrocarbon Contents in Soil Based on Continuum Removal and Wavelet Packet Decomposition
Authors: Chen Chaoqun , Jiang Qigang , Zhang Zhenchao , Shi Pengfei , Xu Yan , Liu Bin , Xi Jing , Chang ShouZhi
Published: May 2020

Hyperspectral remote sensing is widely used to detect petroleum hydrocarbon pollution in soil monitoring. Different spectral pretreatment methods seriously affect the prediction and analysis of petroleum hydrocarbon contents (PHCs). This study adopted a combined spectral data preprocessing technique that improves the prediction accuracy of petroleum hydrocarbons in soil. We combined continuum removal and wavelet packet decomposition (CR–Daubechies 3 (db3)) to process the hyperspectral reflectance data of 26 soil samples in the oil production work area in China and judged the correlation between spectral reflectance and petroleum hydrocarbons in soil. Partial least squares regression was used to construct an optimal model for the inversion of PHCs in soil and the leave-one-out cross-validation was used to select the best factor number. The best model of soil petroleum hydrocarbon inversion was determined by comprehensively comparing the initial spectrum, db3 to high-frequency spectrum, db3 to low-frequency spectrum, after-continuum removal spectrum, CR-db3 to high-frequency spectrum, and CR-db3 to low-frequency spectrum comprehensively. The main contributions of this study are as follows: (1) three-layer decomposition with CR-db3 can improve the correlation between spectral reflectance and PHCs and effectively improve the sensitivity of the spectrum to PHCs; (2) the prediction accuracy of the high-frequency spectrum of wavelet packet decomposition for PHCs in soil is higher than that of low-frequency information; (3) the proposed petroleum hydrocarbon prediction model based on CR-db3 processed spectra to obtain high-frequency information is optimal (coefficient of determination = 0.977, root mean square error of calibration = 3.078, root mean square error of cross-validation = 4.727, root mean square error of prediction = 4.498, ratio of performance to deviation = 6.12).
An Evaluation of Air Transport Sector Operational Efficiency in China based on a Three-Stage DEA Analysis
Authors: Song Mingli , Jia Guangshe , Zhang Puwei
Published: May 2020

Air transport provides important transportation services for economic development; meanwhile, its operation requires massive resource inputs into the air transport sector (ATS). In order to ensure sustainable development of air transport industry, improve the utilization efficiency of resources, and coordinate the development of the ATS and the macroeconomy, the operational efficiency of the industry should be evaluated accurately. However, few studies have analyzed the operational performance of ATSs across different regions. This study therefore constructs an index system and applied a three-stage data envelopment analysis (DEA) approach, which considers various regional environmental factors and statistical noise, to evaluate regional ATS operational performance. China’s 30 provincial ATS operational efficiencies in year 2017 are empirically evaluated using the proposed model. The empirical results show that different levels of environmental factors, such as regional GDP, openness, technical markets, technological development, and consumption, pose various influences on provincial ATS operational efficiency in China. Operational performance evaluation results eliminating these environmental effects in the third stage show considerable differences with that stage 1 results. In addition, corresponding development strategy implications in different provinces and regions are put forward according to the evaluation results.
Can Fishing Tourism Contribute to Conservation and Sustainability via Ecotourism? A Case Study of the Fishery for Giant African Threadfin Polydactylus quadrifilis on the Kwanza Estuary, Angola
Authors: Butler Edward C. , Childs Amber-Robyn , Saayman Andrea , Potts Warren M.
Published: May 2020

It has been suggested that tourism fisheries can raise the value of landed catch, provide alternative livelihoods for local artisanal fishers and, because recreationally caught fishes are often released, simultaneously conserve stocks. However, for fishing tourism to meet ecotourism standards, sustainable, local economic benefit is imperative. This study aimed to assess the direct economic contribution of the recreational fishery for Polydactylus quadrifilis on the Kwanza Estuary, Angola. The recreational fishery contributed significantly to economic productivity in an otherwise rural area, generating a total revenue (TR) of $236,826 per four-month fishing season. Based on TR, P. quadrifilis was 3.6–32.6 times more valuable than the same fish caught and sold in the artisanal sector. However, high rates of economic leakage (86.1% of local TR) reduced the value of recreationally caught fish to below that of artisanally caught fish. Important sources of economic leakage were via the non-local sourcing of lodge supplies, services and staff and through the repatriation of profits. Capacity building within the local community is suggested to reduce leakages and to create ‘linkages’ with the recreational fishery. Greater community involvement, including the provision of business shares and greater communication and control, is suggested to achieve sustainability and incentivise the protection of recreationally important fishery species.
Automatic 3D Modeling and Reconstruction of Cultural Heritage Sites from Twitter Images
Authors: Doulamis Anastasios , Voulodimos Athanasios , Protopapadakis Eftychios , Doulamis Nikolaos , Makantasis Konstantinos
Published: May 2020

This paper presents an approach for leveraging the abundance of images posted on social media like Twitter for large scale 3D reconstruction of cultural heritage landmarks. Twitter allows users to post short messages, including photos, describing a plethora of activities or events, e.g., tweets are used by travelers on vacation, capturing images from various cultural heritage assets. As such, a great number of images are available online, able to drive a successful 3D reconstruction process. However, reconstruction of any asset, based on images mined from Twitter, presents several challenges. There are three main steps that have to be considered: (i) tweets’ content identification, (ii) image retrieval and filtering, and (iii) 3D reconstruction. The proposed approach first extracts key events from unstructured tweet messages and then identifies cultural activities and landmarks. The second stage is the application of a content-based filtering method so that only a small but representative portion of cultural images are selected to support fast 3D reconstruction. The proposed methods are experimentally evaluated using real-world data and comparisons verify the effectiveness of the proposed scheme.
Critical Gap Comparison between One-, Two-, and Three-Lane Roundabouts in Qatar
Authors: Shaaban Khaled , Hamad Hassan
Published: May 2020

A critical gap value of a roundabout is mainly affected by the interactions between the circulating vehicles and vehicles entering the roundabout. These interactions are impacted by many factors, including the number of circulating lanes, the aggressiveness of local drivers, vehicle types, and the number of approaching lanes. Therefore, it is essential to locally investigate critical gap values before conducting any studies to improve capacity and delay at roundabouts. The purpose of this study is to measure and compare the critical gap values for different types of roundabouts in Qatar. More than 10,000 measurements were collected. The results showed that the critical gap values were 2.24 s, 2.55 s, and 2.40 s for the one-, two-, and three-lane roundabouts, respectively. These values are also quite low when compared to values calculated in other countries, which can be an indication of driver aggressiveness and risky behavior. The study is one of the first efforts to compare three types of roundabouts and to understand the difference in operation between them in this region. The results of this study can help engineers, planners, and public agencies to plan, study, and design similar facilities.
The Status of Sustainable Social Innovation in Malta
Authors: Sammut Nicholas , Spiteri Diana , Sammut Joseph Paul , Coppola Irene , Lepre Roberta , Lebrun Benjamin
Published: May 2020

Governments are increasingly using social innovation to stimulate economic growth and address social issues sustainably. Unfortunately, due to its size, Malta faces a very different challenge to sustainably kick-start high-value-added innovative ecosystems compared to larger states. This is due to a number of issues, including diseconomies of scale, that tend to impede conventional innovation policy efforts. Based on grassroots data, this paper presents the results of a study which determined the status of social innovation in Malta and presents a few recommended measures that can be implemented in order to stimulate social innovation sustainably in Malta and possibly in similar small jurisdictions.
A Multi-Filovirus Vaccine Candidate: Co-Expression of Ebola, Sudan, and Marburg Antigens in a Single Vector
Authors: Sebastian Sarah , Flaxman Amy , Cha Kuan M. , Ulaszewska Marta , Gilbride Ciaran , Sharpe Hannah , Wright Edward , Spencer Alexandra J. , Dowall Stuart , Hewson Roger , Gilbert Sarah , Lambe Teresa
Published: May 2020

In the infectious diseases field, protective immunity against individual virus species or strains does not always confer cross-reactive immunity to closely related viruses, leaving individuals susceptible to disease after exposure to related virus species. This is a significant hurdle in the field of vaccine development, in which broadly protective vaccines represent an unmet need. This is particularly evident for filoviruses, as there are multiple family members that can cause lethal haemorrhagic fever, including Zaire ebolavirus, Sudan ebolavirus, and Marburg virus. In an attempt to address this need, both pre-clinical and clinical studies previously used mixed or co-administered monovalent vaccines to prevent filovirus mediated disease. However, these multi-vaccine and multi-dose vaccination regimens do not represent a practical immunisation scheme when considering the target endemic areas. We describe here the development of a single multi-pathogen filovirus vaccine candidate based on a replication-deficient simian adenoviral vector. Our vaccine candidate encodes three different filovirus glycoproteins in one vector and induces strong cellular and humoral immunity to all three viral glycoproteins after a single vaccination. Crucially, it was found to be protective in a stringent Zaire ebolavirus challenge in guinea pigs in a one-shot vaccination regimen. This trivalent filovirus vaccine offers a tenable vaccine product that could be rapidly translated to the clinic to prevent filovirus-mediated viral haemorrhagic fever.
Investigating the Additional Components of Uncertainty of Measurment Result of Unsteady Flow
Authors: Kostyk I. V. , Matiko F. D. , Roman V. I.
Published: May 2020

The additional components of uncertainty of measurement result of unsteady flow by means of pressure differential flowmeter are investigated in the article. In particular, the authors considered in detail the technique for estimating the additional component of uncertainty, caused by the nonlinearity of the flowrate dependence on the pressure drop on the standard primary device, as well as the additional component, which is related to the absence of the inertial term in the root expression of the quasi-steady flow equation. On the example of four differential pressure signals that reproduce the pulsating and unsteady flow modes of the fluid, the estimating the named components is carried out and the dependence of these components of uncertainty on the basic characteristics of the differential pressure signal (root mean square amplitude of pulsations and the maximum relative deviation) is demonstrated. It is shown that the increase of these signal characteristics leads to an increase in the corresponding components of the uncertainty and, consequently, in the resulting additional uncertainty of the measured value of flowrate. Particularly, for the investigated pressure drop signals for which the root mean square amplitude does not exceed 20% of the mean pressure drop, the resulting additional uncertainty of the measured flowrate reaches 0.5%. Since the additional uncertainty caused by unsteady flow is systematic and has a positive sign, it is possible to determine the correction coefficient based on this additional uncertainty and to correct the measured value of the flowrate by considering the correction factor in the flow equation. However, the authors propose to correct the measured value of the flowrate only if it is impossible to identify the causes of unsteady flow and to eliminate their impact on the flowrate.
State Primary Standard of Gas Volume and Flow Rate Units for the Pressure Range of 1 MPa to 5 MPa (PVTt-15)
Authors: Rozhnov M. S. , Kuzmenko Yu. V. , Melnyk D. M. , Levbarg O. S. , Rak A. M. , Pashun V. I. , Pohribna L. M.
Published: May 2020

For the first time in Ukraine a primary measurement standard of gas volume and flow rate units in a pressure range of 1 MPa to 5 MPa has been created. The standard is based on realisation of the units by PVTt principle and units dissemination using critical Venturi nozzles. Gas passing through the nozzle during its calibration fills an evacuated collection tank located downstream the nozzle, and the respective time interval is measured. Mass flow rate is calculated by multiplying the volume of the collection tank by the gas density change and dividing by the tank filling time. Density values are determined by the equation of state and the measured initial and final pressure and temperature values. The structural and functional scheme of the measurement standard is shown in Figure 3.
The standard consists of two units. The first unit is intended to realise, keep and transfer the units of gas volume and flow rate. The general view of the block is shown in Figure 4. The unit contains high pressure collection tank, precision water thermostat, vacuum pump, piston gas pressure gauge, flow switch, fine filter, a set of seven Venturi nozzles with diameters from 0.1 mm to 3.0 mm. The second unit is designed to form a stationary gas flow and provide a critical gas flow rate (at the speed of sound) at the nozzle throat. In the case of an elementary reversible adiabatic (isoentropic) process at a critical velocity, the mass flow rate of gas passing through the nozzle is maximally possible. The unit consists of equipment for reducing the pressure from 150 bar to 70 bar and from 70 bar to 10 bar, the heat exchanger and the instruments measuring the pressure and temperature of the gas flow. The created measurement standard will assure metrological traceability of the measurements of gas volume and volume flow rate at high pressures for the flow rate up to
100 m3/h and calibration of the primary reference nozzles with a throat diameter from 0.1 mm to 3 mm.
THE ARTICLE IS ELLIMINATED
Authors: Board Editorial
Published: May 2020

As the result of the article V. U. Ihnatkin, Yu. L. Zabulonov, Yu. M. Tuz, O. V. Farrakhov
«Calculation and Estimation of the Uncertainty of Pollution Emissions in the Environment»
https://doi.org/10.33955/2307-2180(2)2020.34-39
revision for borrowings from third parties work this article had been elliminated according to the policy of anti-plgiarism as such, that contains, in fact, the complete plagiarism with the similar article published by «Measurement Technics» journal, Russia, N 2, 2009
Metrological Activity At the Enterprise
Authors: Dziabenko O. M.
Published: May 2020

When organizing metrological activity at an enterprise, the question arises of the need to organize verification (metrological confirmation) of measuring equipment that is not used in the field of legislatively regulated.
In the international standards «Quality Management Systems» (ISO 9001, EN 9100, AQAP-2110), to ensure that the requirements of Section 7.1.5 «Resources for Monitoring and Measurement» are met, the requirement is established that all measuring equipment, as part of a measurement management system, must have metrological confirmation in accordance with the requirements of ISO 10012.
Metrological confirmation provides for the calibration and verification of measuring equipment.
Laboratory specialists who carry out metrological confirmation of measuring instruments, establish a relationship between the values of the values that provide the standards, and the result of measuring this quantity using measuring instruments (carry out calibration), based on this ratio establish the conformity / non-compliance of the measuring instruments with the established requirements (carry out verification) and draw up the corresponding supporting document.
After comparing the concepts of metrological confirmation and verification of measuring instruments, we can conclude that metrological confirmation (calibration and verification) of measuring equipment is essentially nothing more than verification of measuring instruments.
Metrological activities to ensure the uniformity of measurements in enterprises should comply with the requirements of ISO 10012: 2003. This standard establishes general requirements and contains recommendations for the management of measurement processes and metrological confirmation of the suitability of measuring equipment, which is used to maintain and demonstrate compliance with metrological requirements.
Compliance with the requirements set forth in the ISO 10012 standard makes it possible to ensure compliance with the measurement requirements and the management of measurement processes established by the international standards «Quality Management Systems».