bluuebunny/crossref_metadata_2025 huggingface dataset:
Sub-ppm-Level Ammonia Detection Using Photoacoustic Spectroscopy with an Optical Microphone Based on a Phase Interferometer
Authors: Bonilla-Manrique Oscar E. , Posada-Roman Julio E. , Garcia-Souto Jose A. , Ruiz-Llata Marta
Published: July 2019

A sensitive optical microphone for photoacoustic spectroscopy based on the common path topology of a fibre laser Doppler vibrometer (FLDV) using phase-generated carrier demodulation and a slim diaphragm as an acoustic wave transducer was demonstrated. A resonant gas cell was adapted to enhance gas-detection performance and simultaneously provide efficient cancellation of the window background acoustic signal. Ammonia (NH3) was selected as the target gas. The absorption line was experimentally identified using a distributed feedback laser diode emitting at 1530 nm. The linearity and sensitivity of the gas sensor were measured using wavelength modulation spectroscopy with second harmonic detection. A Teflon diaphragm was used to implement the optical microphone, along with the FLDV, showing a minimum detectable pressure of 79.5 μPa/Hz1/2. The noise-equivalent absorption sensitivity for NH3 detection at the absorption line at 1531.7 nm was 1.85 × 10−8 W cm−1 Hz−1/2, and the limit of detection was 785 ppbv.
IPSCL: An Accurate Indoor Positioning Algorithm Using Sensors and Crowdsourced Landmarks
Authors: Jang Beakcheol , Kim Hyunjung , Kim Jong Wook
Published: July 2019

Indoor positioning technology has attracted the attention of researchers due to the increasing pervasiveness of smartphones and the development of sensor technology, along with the increase of indoor time. Sensor technology, which is one of the most commonly used data sources for indoor positioning, has the advantage that sensors can receive data from a smartphone without installing any additional device. However, the readings of built-in sensors are easily affected by the surrounding environment and are even occasionally different from each other which adversely influence the accuracy of indoor positioning. Moreover, once an error occurs, it can accumulate because there is not any reference point in the sensor, only in indoor positioning. In this paper, we present an accurate indoor positioning technology, which uses smartphone built-in sensors and Bluetooth beacon-based landmarks. Our proposed algorithm chooses proper one between values of sensors alternately based on their characteristics. It exploits landmarks as the reference points of indoor positioning. It also allows individuals to add the location where they repeatedly detect the same and special beacon received signal strength indicator values as a crowdsourced landmark. Extensive experimental results show that our proposed algorithm facilitates the acquisition of accurate heading direction and coordinates of the user.
3D Tdoa Problem Solution with Four Receiving Nodes
Authors: Díez-González Javier , Álvarez Rubén , Sánchez-González Lidia , Fernández-Robles Laura , Pérez Hilde , Castejón-Limas Manuel
Published: July 2019

Time difference of arrival (TDOA) positioning methods have experienced growing importance over the last few years due to their multiple applications in local positioning systems (LPSs). While five sensors are needed to determine an unequivocal three-dimensional position, systems with four nodes present two different solutions that cannot be discarded according to mathematical standards. In this paper, a new methodology to solve the 3D TDOA problems in a sensor network with four beacons is proposed. A confidence interval, which is defined in this paper as a sphere, is defined to use positioning algorithms with four different nodes. It is proven that the separation between solutions in the four-beacon TDOA problem allows the transformation of the problem into an analogous one in which more receivers are implied due to the geometric properties of the intersection of hyperboloids. The achievement of the distance between solutions needs the application of genetic algorithms in order to find an optimized sensor distribution. Results show that positioning algorithms can be used 96.7% of the time with total security in cases where vehicles travel at less than 25 m/s.
Design Procedure and Experimental Verification of a Broadband Quad-Stable 2-DOF Vibration Energy Harvester
Authors: Zayed Abdelhameed A. A. , Assal Samy F. M. , Nakano Kimihiko , Kaizuka Tsutomu , Fath El-Bab Ahmed M. R.
Published: July 2019

Vibration-based energy harvesters brought the idea of self-powered sensors to reality in the past few years. Many strategies to improve the performance of linear vibration energy harvesters that collect energy over a limited bandwidth have been proposed. In this paper, a bi-stable two degrees of freedom (2-DOF) cut-out vibration energy harvester employing a pair of permanent magnets is designed through a proposed design methodology. Based on this methodology, the nonlinear harvesters can be optimally designed such that the bandwidth can be widened for a targeted output voltage. The proper selection of the harvester parameters as well as the gap distances between the tip and the fixed magnets are the bases of this methodology. The mathematical modeling of the proposed harvester and the formula for the potential energy between the tip and the fixed magnets are presented. Additionally, to enhance the performance of the bi-stable energy harvester (BEH), a quad-stable energy harvester (QEH) was configured by adding more fixed magnets. Experiments were performed to validate the numerical simulations and the results showed that, the simulation and experimental results are consistent. The results indicate that, the QEH covers a wider bandwidth than the BEH and based on a figure of merit the QEH shows the best performance among many harvesters presented in the literature.
Recording of Bipolar Multichannel ECGs by a Smartwatch: Modern ECG Diagnostic 100 Years after Einthoven
Authors: Samol Alexander , Bischof Kristina , Luani Blerim , Pascut Dan , Wiemer Marcus , Kaese Sven
Published: July 2019

Aims: Feasibility study of accurate three lead ECG recording (Einthoven I, II and III) using an Apple Watch Series 4. Methods: In 50 healthy subjects (18 male; age: 40 ± 12 years) without known cardiac disorders, a 12-lead ECG and three bipolar ECGs, corresponding to Einthoven leads I, II and III were recorded using an Apple Watch Series 4. Einthoven I was recorded with the watch on the left wrist and the right index finger on the crown, Einthoven II with the watch on the left lower abdomen and the right index finger on the crown, Einthoven III with the watch on the left lower abdomen and the left index finger on the crown. Four experienced cardiologists were independently asked to assign the watch ECGs to Einthoven leads from 12-lead ECG for each subject. Results: All watch ECGs showed an adequate signal quality with 134 ECGs of good (89%) and 16 of moderate signal quality (11%). Ninety-one percent of all watch ECGs were assigned correctly to corresponding leads from 12-lead ECG. Thirty-nine subjects (78%) were assigned correctly by all cardiologists. All assignment errors occurred in patients with similar morphologies and amplitudes in at least two of the three recorded leads. Erroneous assignment of all watch ECGs to leads from standard ECG occurred in no patient. Conclusion: Recording of Einthoven leads I-III by a smartwatch is accurate and highly comparable to standard ECG. This might contribute to an earlier detection of cardiac disorders, which are associated with repolarization abnormalities or arrhythmias.
Inversion of Lake Bathymetry through Integrating Multi-Temporal Landsat and ICESat Imagery
Authors: Long Yuannan , Yan Shixiong , Jiang Changbo , Wu Changshan , Tang Rong , Hu Shixiong
Published: July 2019

Lake bathymetry provides valuable information for lake basin planning and treatment, lake watershed erosion and siltation management, water resource planning, and environmental protection. Lake bathymetry has been surveyed with sounding techniques, including single-beam and multi-beam sonar sounding, and unmanned ship sounding. Although these techniques have high accuracy, most of them require long survey cycles and entail a high degree of difficulty. On the contrary, optical remote sensing inversion methods are easy to implement, but tend to provide less accurate bathymetry measures, especially when applied to turbid waters. The present study, therefore, aims to improve the accuracy of bathymetry measurements through integrating Landsat Thematic Mapper imagery, the Ice, Cloud, and Land Elevation Satellite’s Geoscience Laser Altimeter System (ICESat/GLAS) data, and water level data measured at hydrological stations. First, the boundaries of a lake at multiple dates were derived using water extraction, initial boundary extraction, and Landsat Thematic Mapper/Enhanced Thematic Mapper (TM/ETM+) strip removal processing techniques. Second, ICESat/GLAS data were introduced to obtain additional topographic information of a lake. The striped topography of a lake’s area was then obtained through eliminating and correcting erroneous points and interpolating the values of unknown points. Third, the entire bathymetry of the lake was obtained through interpolating water level values of lake boundary points in various dates. Experiments show that accurate bathymetry (±1 m) can be successfully derived.
Human–Robot–Environment Interaction Interface for Smart Walker Assisted Gait: AGoRA Walker
Authors: Sierra M. Sergio D. , Garzón Mario , Múnera Marcela , Cifuentes Carlos A.
Published: July 2019

The constant growth of the population with mobility impairments has led to the development of several gait assistance devices. Among these, smart walkers have emerged to provide physical and cognitive interactions during rehabilitation and assistance therapies, by means of robotic and electronic technologies. In this sense, this paper presents the development and implementation of a human–robot–environment interface on a robotic platform that emulates a smart walker, the AGoRA Walker. The interface includes modules such as a navigation system, a human detection system, a safety rules system, a user interaction system, a social interaction system and a set of autonomous and shared control strategies. The interface was validated through several tests on healthy volunteers with no gait impairments. The platform performance and usability was assessed, finding natural and intuitive interaction over the implemented control strategies.
Hyperspectral-Based Estimation of Leaf Nitrogen Content in Corn Using Optimal Selection of Multiple Spectral Variables
Authors: Fan Lingling , Zhao Jinling , Xu Xingang , Liang Dong , Yang Guijun , Feng Haikuan , Yang Hao , Wang Yulong , Chen Guo , Wei Pengfei
Published: July 2019

Accurate and dynamic monitoring of crop nitrogen status is the basis of scientific decisions regarding fertilization. In this study, we compared and analyzed three types of spectral variables: Sensitive spectral bands, the position of spectral features, and typical hyperspectral vegetation indices. First, the Savitzky-Golay technique was used to smooth the original spectrum, following which three types of spectral parameters describing crop spectral characteristics were extracted. Next, the successive projections algorithm (SPA) was adopted to screen out the sensitive variable set from each type of parameters. Finally, partial least squares (PLS) regression and random forest (RF) algorithms were used to comprehensively compare and analyze the performance of different types of spectral variables for estimating corn leaf nitrogen content (LNC). The results show that the integrated variable set composed of the optimal ones screened by SPA from three types of variables had the best performance for LNC estimation by the validation data set, with the values of R2, root means square error (RMSE), and normalized root mean square error (NRMSE) of 0.77, 0.31, and 17.1%, and 0.55, 0.43, and 23.9% from PLS and RF, respectively. It indicates that the PLS model with optimally multitype spectral variables can provide better fits and be a more effective tool for evaluating corn LNC.
Energy, Carbon and Renewable Energy: Candidate Metrics for Green-Aware Routing?
Authors: Hossain Md. Mohaimenul , Georges Jean-Philippe , Rondeau Eric , Divoux Thierry
Published: July 2019

There are all sort of indications that Internet usage will go only upwards, resulting in an increase in energy consumption and CO2 emissions. At the same time, a significant amount of this carbon footprint corresponds to the information and communication technologies (ICT) sector, with around one third being due to networking. In this paper we have approached the problem of green networking from the point of view of sustainability. Here, alongside energy-aware routing, we have also introduced pollution-aware routing with environmental metrics like carbon emission factor and non-renewable energy usage percentage. We have proposed an algorithm based on these three candidate-metrics. Our algorithm provides optimum data and control planes for three different metrics which regulate the usage of different routers and adapt the bandwidth of the links while giving the traffic demand requirements utmost priority. We have made a comparison between these three metrics in order to show their impact on greening routing. The results show that for a particular scenario, our pollution-aware routing algorithm can reduce 36% and 20% of CO2 emissions compared to shortest path first and energy-based solutions, respectively.
Speckle Noise Filtering in Side-Scan Sonar Images Based on the Tucker Tensor Decomposition
Authors: Grabek Jakub , Cyganek Bogusław
Published: July 2019

Real signals are usually contaminated with various types of noise. This phenomenon has a negative impact on the operation of systems that rely on signals processing. In this paper, we propose a tensor-based method for speckle noise reduction in the side-scan sonar images. The method is based on the Tucker decomposition with automatically determined ranks of factoring tensors. As verified experimentally, the proposed method shows very good results, outperforming other types of speckle-noise filters.
NINQ: Name-Integrated Query Framework for Named-Data Networking of Things
Authors: Rehman Muhammad Atif Ur , Ullah Rehmat , Kim Byung Seo
Published: July 2019

Information-Centric Networking (ICN) is a paradigm shift from host-to-host Internet Protocol (IP)-based communication to content-based communication. In ICN, the content-retrieval process employs names that are given through different naming schemes such as hierarchical, flat, attribute, and hybrid. Among different ICN architectures, Named-Data Networking (NDN) has gained much interest in the research community and is actively being explored for the Internet of Things (IoT) and sensor networks, and follows a hierarchical naming format. NDN protocol follows a pull-based communication model where the content consumer gets content irrespective of the location of the content provider. The content provider in NDN and sensor networks can be considered to be a distributed database that monitors or controls the environment and caches the sensed data or controls information into their memory. The proposed Name-INtegrated Query (NINQ) framework for NDN-based IoT provides a flexible, expressive, and secure query mechanism that supports content retrieval as well as control and configuration command exchange among various nodes in a smart building. Different use cases are presented in this paper that expand on the behavior of proposed query framework in different scenarios. Simulation results of data collection and exchange of control commands show that proposed query framework significantly improves Interest Satisfaction Rate (ISR), Command Satisfaction Rate (CSR), energy efficiency, and average delay. Moreover, it is evident from the simulation results that proposed query framework significantly reduces the number of transmissions in the network in both data collection and exchange of control command scenarios, which improves the network performance.
A Wireless Visualized Sensing System with Prosthesis Pose Reconstruction for Total Knee Arthroplasty
Authors: Jiang Hanjun , Xiang Shaolin , Guo Yanshu , Wang Zhihua
Published: July 2019

The surgery quality of the total knee arthroplasty (TKA) depends on how accurate the knee prosthesis is implanted. The knee prosthesis is composed of the femoral component, the plastic spacer and the tibia component. The instant and kinetic relative pose of the knee prosthesis is one key aspect for the surgery quality evaluation. In this work, a wireless visualized sensing system with the instant and kinetic prosthesis pose reconstruction has been proposed and implemented. The system consists of a multimodal sensing device, a wireless data receiver and a data processing workstation. The sensing device has the identical shape and size as the spacer. During the surgery, the sensing device temporarily replaces the spacer and captures the images and the contact force distribution inside the knee joint prosthesis. It is connected to the external data receiver wirelessly through a 432 MHz data link, and the data is then sent to the workstation for processing. The signal processing method to analyze the instant and kinetic prosthesis pose from the image data has been investigated. Experiments on the prototype system show that the absolute reconstruction errors of the flexion-extension rotation angle (the pitch rotation of the femoral component around the horizontal long axis of the spacer), the internal–external rotation (the yaw rotation of the femoral component around the spacer vertical axis) and the mediolateral translation displacement between the centers of the femoral component and the spacer based on the image data are less than 1.73°, 1.08° and 1.55 mm, respectively. It provides a force balance measurement with error less than ±5 N. The experiments also show that kinetic pose reconstruction can be used to detect the surgery defection that cannot be detected by the force measurement or instant pose reconstruction.
Validation of Sentinel-3A/3B Satellite Altimetry Wave Heights with Buoy and Jason-3 Data
Authors: Yang Jungang , Zhang Jie
Published: July 2019

The validation of significant wave height (SWH) data measured by the Sentinel-3A/3B SAR Altimeter (SRAL) is essential for the application of the data in ocean wave monitoring, forecasting and wave climate studies. Sentinel-3A/3B SWH data are validated by comparisons with U. S. National Data Buoy Center (NDBC) buoys, using a spatial scale of 25 km and a temporal scale of 30 min, and with Jason-3 data at their crossovers, using a time difference of less than 30 min. The comparisons with NDBC buoy data show that the root-mean-square error (RMSE) of Sentinel-3A SWH is 0.30 m, and that of Sentinel-3B is no more than 0.31 m. The pseudo-Low-Resolution Mode (PLRM) SWH is slightly better than that of the Synthetic Aperture Radar (SAR) mode. The statistical analysis of Sentinel-3A/3B SWH in the bin of 0.5 m wave height shows that the accuracy of Sentinel-3A/3B SWH data decreases with increasing wave height. The analysis of the monthly biases and RMSEs of Sentinel-3A SWH shows that Sentinel-3A SWH are stable and have a slight upward trend with time. The comparisons with Jason-3 data show that SWH of Sentinel-3A and Jason-3 are consistent in the global ocean. Finally, the piecewise calibration functions are given for the calibration of Sentinel-3A/3B SWH. The results of the study show that Sentinel-3A/3B SWH data have high accuracy and remain stable.
Adaptive Motion Artifact Reduction Based on Empirical Wavelet Transform and Wavelet Thresholding for the Non-Contact ECG Monitoring Systems
Authors: Xu Xiaowen , Liang Ying , He Pei , Yang Junliang
Published: July 2019

Electrocardiogram (ECG) signals are crucial for determining the health status of the human heart. A clean ECG signal is critical in analysis and diagnosis of heart diseases. However, ECG signals are often contaminated by motion artifact noise in the non-contact ECG monitoring systems. In this paper, an ECG motion artifact removal approach based on empirical wavelet transform (EWT) and wavelet thresholding (WT) is proposed. This method consists of five steps, namely, spectrum preprocessing, spectrum segmentation, EWT decomposition, wavelet threshold denoising, and EWT reconstruction. The proposed approach was used to process real ECG signals collected by the non-contact ECG monitoring equipment. The results of quantitative study and analysis indicate that this approach produces a better performance in terms of restorage of QRS complexes of the original ECG with reduced distortion, retaining useful information in ECG signals, and improvement of the signal to noise ratio (SNR) value of the signal. The output results of the practical ECG signal test show that motion artifact in the real recorded ECG is effectively filtered out. The proposed method is feasible for reducing motion artifacts from ECG signals, whether from simulation ECG signals or practical non-contact ECG monitoring systems.
Laplacian Eigenmaps Network-Based Nonlocal Means Method for MR Image Denoising
Authors: Yu Houqiang , Ding Mingyue , Zhang Xuming
Published: July 2019

Magnetic resonance (MR) images are often corrupted by Rician noise which degrades the accuracy of image-based diagnosis tasks. The nonlocal means (NLM) method is a representative filter in denoising MR images due to its competitive denoising performance. However, the existing NLM methods usually exploit the gray-level information or hand-crafted features to evaluate the similarity between image patches, which is disadvantageous for preserving the image details while smoothing out noise. In this paper, an improved nonlocal means method is proposed for removing Rician noise in MR images by using the refined similarity measures. The proposed method firstly extracts the intrinsic features from the pre-denoised image using a shallow convolutional neural network named Laplacian eigenmaps network (LEPNet). Then, the extracted features are used for computing the similarity in the NLM method to produce the denoised image. Finally, the method noise of the denoised image is utilized to further improve the denoising performance. Specifically, the LEPNet model is composed of two cascaded convolutional layers and a nonlinear output layer, in which the Laplacian eigenmaps are employed to learn the filter bank in the convolutional layers and the Leaky Rectified Linear Unit activation function is used in the final output layer to output the nonlinear features. Due to the advantage of LEPNet in recovering the geometric structure of the manifold in the low-dimension space, the features extracted by this network can facilitate characterizing the self-similarity better than the existing NLM methods. Experiments have been performed on the BrainWeb phantom and the real images. Experimental results demonstrate that among several compared denoising methods, the proposed method can provide more effective noise removal and better details preservation in terms of human vision and such objective indexes as peak signal-to-noise ratio (PSNR) and structural similarity index measure (SSIM).
Predicting Traffic and Risk Exposure in the Maritime Industry
Authors: Vander Hoorn Stephen , Knapp Sabine
Published: July 2019

Maritime regulators, port authorities, and industry require the ability to predict risk exposure of shipping activities at a micro and macro level to optimize asset allocation and to mitigate and prevent incidents. This article introduces the concept of a strategic planning tool by making use of the multi-layered risk estimation framework (MLREF), which accounts for ship specific risk, vessel traffic densities, and meets ocean conditions at the macro level. This article’s main contribution is to provide a traffic and risk exposure prediction routine that allows the traffic forecast to be distributed across the shipping route network to allow for predicting scenarios at the macro level (e.g., covering larger geographic areas) and micro level (e.g., passage way, particular route of interest). In addition, the micro level is introduced by providing a theoretical idea to integrate location specific spatial rate ratios along with the effect of the risk control option to perform sensitivity analysis of risk exposure prediction scenarios. Aspects of the risk exposure estimation routine were tested via a pilot study for the Australian region using a comprehensive and unique combination of datasets. Sources of uncertainties for risk assessments are described in general and discussed along with the potential for future developments and improvements.
A Comparative Study of Traditional and Contemporary Building Envelope Construction Techniques in Terms of Thermal Comfort and Energy Efficiency in Hot and Humid Climates
Authors: Lotfabadi Pooya , Hançer Polat
Published: July 2019

Expectations of traditional and contemporary buildings are different in terms of thermal comfort. Traditional buildings mostly achieve comfort through passive means, without HVAC support, but old levels of thermal satisfaction do not meet today’s expectations, although their passive thermal performances are notable for contemporary building designs. In this regard, the current study tries to investigate the possibility of comparing traditional and contemporary buildings’ construction techniques to achieve thermal comfort from an architectural point of view. In other words, is it possible to achieve passive building design by considering vernacular architecture principals as a reference? Likewise, how well can architects define insulation layers in contemporary construction surfaces in hot and humid climates? To this end, a dynamic, numerical, thermal calculation case study has been modeled in Famagusta, Northern Cyprus, to answer the above-mentioned questions. A mixed-use mode benefitting free-run periods is proposed and compared with a mode providing 24 hours of air-conditioning in different scenarios using the same initial settings. Thus, different floor-to-ceiling heights, insulation placements and indoor conditions have been tested separately in both winter and summer periods. The results show that thermal comfort can be achieved in free-run periods only during a limited percentage of the year. Furthermore, although increasing building heights may lead to a rise in the free-run periods, in contemporary buildings it increases the total energy usage of the buildings between 6% and 9% in the mixed mode. Therefore, vernacular architecture strategies are proper in their own context. However, this energy usage can still be controlled and optimized by such considerations as insulation material placement. In this regard, the best envelope properties for different building functions are proposed for application in hot and humid climates.
Shifting Towards Sustainable Tourism: Organizational and Financial Scenarios for Solid Waste Management in Tourism Destinations in Tunisia
Authors: Chaabane Wassim , Nassour Abdallah , Bartnik Sabine , Bünemann Agnes , Nelles Michael
Published: July 2019

Tourism in Tunisia generates large amounts of solid waste, especially during the summer, and doubles the amount in most big tourism cities like Hammamet, which makes its management more complicated. Municipalities lack the financial means to ensure sustainable solid waste management (SWM) in tourist areas and need an intervention from all actors to reduce financial and technical pressures and implement sustainable solutions. This paper presents a descriptive research method that focuses on an analysis of the current SWM concept in tourism areas in Tunisia and proposes new sustainable organizational and financial models. These are based on the collaboration of different stakeholders at both national and local levels; and supported by extending the responsibility of the producer through the creation of a new system operator to take charge of the organization and financing of packaging disposal and recycling activities. In addition, the extension of the recovered material for recycling through extended producer responsibility (EPR) could support the system. The performance of current SWM shows that it has failed to ensure the cleanliness of tourism destinations is sustainable. Tunisia generates 2.8 million tons of municipal solid waste (MSW), between 20% to 30% of which are recyclable materials. The current system for packaging in Tunisia (ECO-Lef) only collected 3400 tons in 2018 compared to 15,800 tons in 2010, and the total recycling rate in the country does not exceed 5%, which makes the waste management system inefficient and unsustainable. Proposed solutions should be supported by legal and technical interventions, such as waste prevention, minimization, sorting at source, and the provision of education programs for citizens and tourism establishments.
Pyrolysis and Thermogravimetric Study to Elucidate the Bioenergy Potential of Novel Feedstock Produced on Poor Soils While Keeping the Environmental Sustainability Intact
Authors: Ahmad Muhammad Sajjad , Mehmood Muhammad Aamer , Luo Huibo , Shen Boxiong , Latif Muhammad , Ghani Wan Azlina Wan Ab Karim , Alkhattabi Nuha Abdulhamid , Aloqbi Akram Ahmed , Jambi Ebtihaj Jamaluddin , Gull Munazza , Rashid Umer
Published: July 2019

This work focused on exploring the bioenergy potential of biomass produced on salt-affected soils by growing two types of grasses, namely Parthenium hysterophorus (carrot grass) and Pennesetum benthiumo (mott grass), without using fertilizers or pesticides. The whole plant biomass of both grasses was pyrolyzed at three heating rates (10, 30, and 50 °C min−1) in a joined Thermogravimetry–Differential Scanning Calorimetry (TGA–DSC) analyzer under an inert (nitrogen) environment. The pyrolysis of both grasses was shown to occur in a three-stage process, while most of the thermal transformation occurred at the temperature range of 240–400 °C. The pyrolytic behavior was assessed by estimating the kinetic parameters, using the isoconversional models of Kissenger–Akahira–Sunose and Ozawa–Flynn–Wall. The average values of the activation energy of carrot and mott grasses were shown to be 267 kJ mol−1 (R2 ≥ 0.98) and 188 kJ mol−1 (R2 ≥ 0.98), indicating the suitability of both grasses for co-pyrolysis. Whereas, the difference in the values of enthalpy change and the activation energy was shown to be <~5 kJ mol−1 at each fractional point, which indicated that the product formation was being favored. Moreover, the high heating values of carrot grass (18.25 MJ kg−1) and mott grass (18.63 MJ kg−1) have shown a remarkable bioenergy potential and suitability of co-pyrolysis for both grasses. This study will lead to establishing an energy-efficient and cost-effective process for the thermal transformation of biomass to bioenergy.
Are Ecological Modernization Narratives Useful for Understanding and Steering Social-Ecological Change in the Argentine Chaco?
Authors: Mastrangelo Matías E. , Aguiar Sebastián
Published: July 2019

During the past decades, the Ecological Modernization Theory, and associated ideas such as the Forest Transition Theory and Land Sparing Hypothesis, have dominated the academic and policy arenas regarding the solutions to current environmental crises. However, critiques were raised as these theories, originally conceived for developed countries, started to be applied in developing countries for explaining and prescribing social-ecological transitions. Here, we assess the validity of five key assumptions of Ecological Modernization narratives as applied to the Argentine Chaco, a global deforestation hotspot. We reviewed existing literature and conducted straightforward analysis to disentangle relationships among key variables. Although agriculture intensified, there is no evidence that this intensification inhibited agricultural expansion. Rural depopulation took place between 2001 and 2010; however, deforestation rates did not decrease, and the quality of life of migrants did not increase compared to those that stayed in rural areas. Our review suggests that the consequences of agriculture intensification on biodiversity and the provision of multiple ecosystem services exceeds the area used. Therefore, available evidence does not support the assumed causal relationships of Ecological Modernization, and even contradicts most assumptions. We propose a series of analytical shifts to better capture the complexity of social-ecological transitions in modern commodity frontiers.
Success of Social Media Marketing Efforts in Retaining Sustainable Online Consumers: An Empirical Analysis on the Online Fashion Retail Market
Authors: Wang Yong , Chowdhury Ahmed Shamim , Deng Shejun , Wang Haizhong
Published: July 2019

This research examines the overall performance achievement of social media marketing (SMM) in Bangladesh by determining whether social media is successful in creating brand consciousness (i.e., brand preference, brand attachment, brand association, and brand loyalty) toward online consumers, which in turn may lead to buying commitment. In total, 564 Bangladeshi consumers were surveyed to monitor their responsiveness toward social media-aided motivations. We selected the online buying environment in Bangladesh, which is an emerging market established less than one decade ago. We specifically choose the entire local fashion industry as our target market, excluding the websites of international fashion brands operated overseas. We used the holistic concept of the five aspects of SMM, namely, interaction, entertainment, customization, electronic word of mouth (eWOM), and trendiness. Moreover, we statistically calculated the performance of social media through the consequences of five measures, namely, brand loyalty, brand preference, brand attachment, brand association, and buying commitment. We used regular linear multiple regression, correlation, and descriptive statistics to obtain statistical results. The study found strong evidence that SMM efforts (SMMEs) of the local Bangladeshi fashion industry are successful in establishing consumer attachment and preference. However, they fail to secure committed buyers when the measurement scale is below 50%. In line with the results of previous studies on consumer loyalty, our results demonstrate that SMMEs fail to create committed buyers. Lack of loyalty and association drive consumers to become uncommitted buyers.
Operating Performance of Chinese Online Shopping Companies: An Analysis Using DuPont Components
Authors: Hao Yue , Choi Seung Uk
Published: July 2019

Chinese online shopping industry has grown dramatically in recent decades. The purpose of this study is to investigate the key factors that affect the operating performance of online shopping companies in China. In particular, the study examines the three features of Chinese online shopping companies: (i) Multi-complex products/a single-special product, (ii) online store only/online and offline stores, (iii) US-listed/China-listed. The tests are leveraged by applying DuPont analysis which is widely used for identifying the sources of operating performance. DuPont analysis decomposes ROA (return on assets) into ATO (asset turnover) and PM (profit margin). A higher ATO represents efficient use of assets while a higher PM indicates efficient cost structure. By using seven Chinese online shopping companies, we find that companies selling multi-complex products have a higher ATO than companies selling a single-special product. However, multi-complex companies’ PM is lower than that of single-special companies, with no difference in ROA between those two groups. Second, online shopping companies with offline stores have a lower PM and ROA than online store only companies. Lastly, we document that US-listed online shopping companies have a higher ATO, PM, and ROA than China-listed companies. The results of this study provide important implications for the future development of the Chinese shopping industry. The findings may present the current situation and shortcomings of the companies, thereby playing a guiding role in the management and development of online shopping companies in China.
Hydroponic Lettuce Production Using Treated Post-Hydrothermal Liquefaction Wastewater (PHW)
Authors: Jesse Samuel D. , Zhang Yuanhui , Margenot Andrew J. , Davidson Paul C.
Published: July 2019

Post-hydrothermal liquefaction wastewater (PHW) is a byproduct of the hydrothermal liquefaction (HTL) process. Previous research indicates that PHW is free of pathogens and contains nutrients needed for crop growth, but may contain metal(loid)s. This study evaluated the ability of differentially treated PHW for effective and safe hydroponic lettuce production. Water containing only hydroponic fertilizer (Source Water 1) had the highest total dry yield of all five treatments; 3.1 times higher than Source Water 2 (diluted PHW with sand filtration), 3.5 times higher than Source Water 3 (diluted PHW with sand + carbon filtration), 2.6 times higher than Source Water 4 (diluted and nitrified PHW with sand filtration), and 1.3 times higher than Source Water 5 (diluted PHW supplemented with hydroponic fertilizer). Findings also indicated that while PHW was below the US Department of Agriculture Foreign Agriculture Service maximum levels for cadmium, lead, and mercury in food, the concentration of arsenic was 1.6, 2.4, and 2.0 times higher than the maximum level for Source Waters 2, 3, and 4, respectively. There was no detectable E. coli or fecal coliforms in any of the treated PHW. While nitrogen was present in the raw PHW, only 0.03% was NO3-N and NO2-N. Diluted PHW supplemented with hydroponic fertilizer had lower lettuce yield than hydroponic fertilizer alone, indicating a potential non-nutrient inhibition of plant growth by PHW. Therefore, this research demonstrates that treated PHW does not pose a biological contamination risk for lettuce, but may entail levels of arsenic in edible leaf tissues that are in excess of safe levels. Additional treatment of PHW can benefit crop production by allowing crop utilization of a greater fraction of total nitrogen in the raw PHW.
Bibliometric Analysis on Smart Cities Research
Authors: Guo Yi-Ming , Huang Zhen-Ling , Guo Ji , Li Hua , Guo Xing-Rong , Nkeli Mpeoane Judith
Published: July 2019

Smart cities have been a global concern in recent years, involving comprehensive scientific research. To obtain a structural overview and assist researchers in making insights into the characteristics of smart cities research, bibliometric analysis was carried out in this paper. With the application of the bibliometric analysis software VOSviewer and CiteSpace, 4409 smart cities were identified by the core collection of the Web of Science in publications between 1998 and 2019 and used in the analysis of this paper. Concretely, this research visually demonstrates a comprehensive overview of the field relating to smart cities in terms of the production of regular publications, main domain of smart cities researchers, most influential countries (institutions, sources and authors), and interesting research directions in the smart city researches. We also present the research collaboration among countries (regions), organizations and authors based on a series of cooperation analyses. The bibliometric analysis of the existing work provided a valuable and seminal reference for researchers and practitioners in smart cities-related research communities.
An Observatory Framework for Metropolitan Change: Understanding Urban Social–Ecological–Technical Systems in Texas and Beyond
Authors: Bixler R. Patrick , Lieberknecht Katherine , Leite Fernanda , Felkner Juliana , Oden Michael , Richter Steven M. , Atshan Samer , Zilveti Alvaro , Thomas Rachel
Published: July 2019

In Texas and elsewhere, the looming realities of rapid population growth and intensifying effects of climate change mean that the things we rely on to live—water, energy, dependable infrastructure, social cohesion, and an ecosystem to support them—are exposed to unprecedented risk. Limited resources will be in ever greater demand and the environmental stress from prolonged droughts, record-breaking heat waves, and destructive floods will increase. Existing long-term trends and behaviors will not be sustainable. That is our current trajectory, but we can still change course. Significant advances in information communication technologies and big data, combined with new frameworks for thinking about urban places as social–ecological–technical systems, and an increasing movement towards transdisciplinary scholarship and practice sets the foundation and framework for a metropolitan observatory. Yet, more is required than an infrastructure for data. Making cities inclusive, safe, resilient, and sustainable will require that data become actionable knowledge that change policy and practice. Research and development of urban sustainability and resilience knowledge is burgeoning, yet the uptake to policy has been slow. An integrative and holistic approach is necessary to develop effective sustainability science that synthesizes different sources of knowledge, relevant disciplines, multi-sectoral alliances, and connections to policy-makers and the public. To address these challenges and opportunities, we developed a conceptual framework for a “metropolitan observatory” to generate standardized long-term, large-scale datasets about social, ecological, and technical dimensions of metropolitan systems. We apply this conceptual model in Texas, known as the Texas Metro Observatory, to advance strategic research and decision-making at the intersection of urbanization and climate change. The Texas Metro Observatory project is part of Planet Texas 2050, a University of Texas Austin grand challenge initiative.
Assessment of the Economic and Social Impact Using SROI: An Application to Sport Companies
Authors: Lombardo Giovanni , Mazzocchetti Andrea , Rapallo Irene , Tayser Nader , Cincotti Silvano
Published: July 2019

This paper evaluates the social impact of a football club and its philanthropic organization on the local community and its stakeholders, namely supporters, sponsors, players, and shopkeepers. The methodology used is the Social Return on Investment (SROI). SROI methodology includes all the beneficiaries that are beyond the scope of the company’s accounting and its fiscal and financial statements. The aim is to assess both the benefits and the negative impacts of a company’s activities on stakeholders. This type of analysis combines the use of qualitative, quantitative and financial information gathered and analyzes them in order to estimate the amount of “value”, including mental health and well-being, created or destroyed by a business activity, by a project or by the overall operation of an organization. The sport club under review in the present analysis is called Virtus Entella, an Italian football club playing in the second division. An SROI indicator was applied in reference to the business activity that took place during the championship season 2017/2018. Results show that the social impact created during the championship amounts to approximately 44 million Euro against a financial investment of 15 million Euro, producing an SROI ratio of 2.98:1. This outcome suggests that for every euro invested by the football club, about 3 Euros of social value is created.
Understanding Food Literacy in Urban Gardeners: A Case Study of the Twin Cities, Minnesota
Authors: Grubb Megan , Vogl Christian R.
Published: July 2019

Substantial urbanization has allowed individuals to become increasingly spatially and psychologically distanced from the food system and agricultural practices. Food literacy (FL) has been described as a promising approach to reconnect the city with the country and furthermore address public health issues such as obesity and diet-related disease. The present study examined urban gardening through the lens of the FL approach to determine whether a relationship exists between gardening and FL. The research further investigated the relationship between FL and gardener demographics, participation in educational garden events and socialization among gardeners. Data was collected using an online questionnaire targeted to reach community gardeners (n = 181) in Minneapolis and Saint Paul, Minnesota. The research utilized a novel exam and self-perception based measurement tool to assess gardeners’ level of FL. Results indicated a moderately positive relationship between the years of gardening experience and higher individual FL scores. Participants with higher levels of FL were older individuals and more highly educated. There was no significant difference in FL between gardeners who attended educational events and those that had not. The present research presents an initial investigation into the relationship between food literacy and gardening. This research indicates gardening may warrant consideration in holistic approaches to food literacy but further investigation would be valuable.
Erratum: Feng, X., et al. Gas Multiple Flow Mechanisms and Apparent Permeability Evaluation in Shale Reservoirs. Sustainability 2019, 11, 2114
Authors: Feng Xuelei , Ma Fengshan , Zhao Haijun , Liu Gang , Guo Jie
Published: July 2019

The authors did not notice during the proofreading phase that we have accidentally deleted a related reference of Figure 1 [...]
Antecedents of Knowledge Interaction in the Sustainable Interdisciplinary Research Team: A Mixed Research Method
Authors: Cheng Xue , Pan Wei , Zhang Qingpu
Published: July 2019

This paper mainly focuses on two questions: (1) Which factors mainly influence knowledge interaction in a sustainable interdisciplinary research team (SIDRT)? and (2) How are knowledge interaction processes structured in a SIDRT? This paper first defines the conception of knowledge interaction in a SIDRT from the complex system perspective. Then the model of key influencing factors in a SIDRT is constructed through grounded theory, including subjects’ attributes, objects’ characteristics, environment, and resources of knowledge interaction. Furthermore, we propose hypotheses and empirically validate our conceptual model. The combination of the two methods can strengthen the research conclusions from different angles. Finally, based on our qualitative and quantitative results, the theoretical and practical implications are discussed.
Two-Dimensional Finite Element in General Plane Motion Used in the Analysis of Multi-Body Systems
Authors: Chircan Eliza , Scutaru Maria-Luminiţa , Pruncu Cătălin Iulian
Published: July 2019

A description of the motion equation of a single two-dimensional finite element used to model a multi-body system with elastic elements is made in the article. To establish them, the Lagrange’s equations are used. Obtaining the dynamic response of a system with deformable components has become important for technical applications in recent decades. These engineering applications are characterized by high applied loads and high acceleration and velocities. A study of such mechanical systems leads to the identification of different mechanical phenomena (due to high deformations, resonance phenomena, and stability). Coriolis effects and relative motions significantly modify the motion equations and, implicitly, the dynamic response. These effects are highlighted in this paper for plane motion.