bluuebunny/crossref_metadata_2025 huggingface dataset:
Anatase TiO2-Decorated Graphitic Carbon Nitride for Photocatalytic Conversion of Carbon Dioxide
Authors: Tseng I-Hsiang , Sung Yu-Min , Chang Po-Ya , Chen Chin-Yi
Published: January 2019

Three types of graphitic carbon nitride (gCN) nanosheets were derived from direct thermal condensation of urea, melamine, and dicyandiamide, respectively. As the sample (uCN) synthesized from urea exhibited porous morphology and highest surface area among other gCN, anatase TiO2 nanoparticles were then in-situ deposited on uCN via solvothermal process without further calcination. The resultant Ti/uCN_x samples remained with higher surface area and exhibited visible-light activity. The derived band structure of each sample also confirmed its ability to photoreduce CO2. XPS results revealed surface compositions of each sample. Those functional groups governed adsorption of reactant, interfacial interaction, electron transfer rate, and consequently influenced the yield of products. Carbon monoxide and methanol were detected from LED-lamp illuminated samples under appropriate moisture content. Samples with higher ratio of terminal amine groups produced more CO. The presence of hydroxyl groups promoted the initial conversion of methanol. The obtained Ti/uCN_0.5 and Ti/uCN_1.5 samples exhibited better quantum efficiency toward CO2 conversion and demonstrated stability to consistently produce CO under cycling photoreaction.
The Improvement Effect and Mechanism of Longitudinal Ultrasonic Vibration on the Injection Molding Quality of a Polymeric Micro-Needle Array
Authors: Gao Shan , Qiu Zhongjun , Ouyang Junhao
Published: January 2019

A polymeric micro-needle array with high quality has been fabricated using a longitudinal ultrasonic-assisted micro-injection molding (LUμIM) method. To realize the practicability and stability in actual industrial processing, this paper is aimed at studying the improvement mechanism of ultrasonic vibration on the molding quality. The melt-filling process in the micro-needle array cavity is simulated, and the improvement effect of ultrasonic vibration is discussed. The enhancement effect of ultrasonic vibration on material properties of polypropylene and polymethylmethacrylate parts are experimentally investigated. The results show that in the manufacturing of the micro-needle array part using LUμIM, the mold-filling quality is improved by the enhanced melt filling capability and pressure compensation effect, which are caused by the increased corner viscosity gradient, reduced the filling time and melt viscosity under ultrasonic vibration. Material properties of both the semi-crystalline polymer and amorphous polymer could be enhanced by the transformation of micromorphology. It is proved that for a semi-crystalline polymer, this novel method could be employed as a material properties enhancement method, and an optimal excitation voltage of ultrasonic vibration is obtained to achieve the best material properties.
A Comparative Study on the Characterization of Nanofibers with Cellulose I, I/II, and II Polymorphs from Wood
Authors: Wang Haiying , Li Suiyi , Wu Tiantian , Wang Xiaoxuan , Cheng Xudong , Li Dagang
Published: January 2019

Polymorphic changes in cellulose nanofibers (CNFs) are closely related to their properties and applications, and it is of interest to investigate how polymorphic changes influence their properties. A comparative study on the properties of CNFs with cellulose I, I/II, and II polymorphs from wood was conducted herein. CNFs were obtained by chemical extraction combined with a simple and efficient mechanical treatment (one pass through a grinder). This process resulted in a relatively high yield of 80–85% after a simple grinding treatment. The polymorphic changes in the CNFs and the chemical composition, morphology, tensile performances, and thermal properties were systematically characterized and compared. The X-ray diffraction and FTIR analyses verified the existence of three types of purified pulps and CNFs with cellulose I, cellulose I/II, and cellulose II polymorphs (CNF-I, CNF-I/II, CNF-II). Morphological observations presented that these three types of CNFs all exhibited high aspect ratios and entangled structures. Tensile testing showed that the CNF films all exhibited high tensile strengths, and the fracture strains of the CNF-I/II (11.8%) and CNF-II (13.0%) films were noticeably increased compared to those of the CNF-I film (6.0%). If CNF-II is used as reinforcing material, its larger fracture strain can improve the mechanical performance of the CNF composites, such as fracture toughness and impact strength. In addition, CNF-I, CNF-I/II, and CNF-II films showed very low thermal expansion in the range 20–150 °C, with the coefficient of thermal expansion values of 9.4, 17.1, and 17.3 ppm/K, respectively. Thermogravimetric analysis (TGA) revealed that the degradation temperature of CNF-I and CNF-II was greater than that of CNF-I/II, which was likely due to increased α-cellulose content. This comparative study of the characterization of CNF-I, CNF-I/II, and CNF-II provides a theoretical basis for the application of CNFs with different polymorphs and could broaden the applications of CNFs.
Orientation and Dispersion Evolution of Carbon Nanotubes in Ultra High Molecular Weight Polyethylene Composites under Extensional-Shear Coupled Flow: A Dissipative Particle Dynamics Study
Authors: Wang Junxia , Cao Changlin , Chen Xiaochuan , Ren Shijie , Chen Yu , Yu Dingshan , Chen Xudong
Published: January 2019

The property of carbon nanotubes (CNTs)-based composites are significantly dependent on the orientation and dispersion evolution of CNTs in the polymer matrix. In this work, the dissipative particle dynamics (DPD) simulations are employed to discover the orientation and dispersion evolution of CNTs in ultra–high molecular weight polyethylene (UHMWPE) under extensional–shear coupled flow conditions for the first time. In this paper, we investigate the roles of the increasing extensional-shear coupled rate in morphology of CNTs/UHMWPE composites by varying CNTs concentration and observe that the system under consideration lies in the same evolution morphologies. When comparing our results for various morphologies, we notice that the orientation is affected more significantly by changing the extensional-shear coupled rates. A good alignment appears with an increase of extensional-shear coupled rates, which transform it into ordered morphology. In addition, a higher extensional-shear coupled rate does not necessarily contribute to better dispersion even though CNTs concentration varies, as shown by the mean square displacement (MSD) and the relative concentration distribution functions of CNTs in CNTs/UHMWPE composites.
Solubility Difference between Pectic Fractions from Creeping Fig Seeds
Authors: Wang Ri-si , He Xiao-hong , Lin Hong , Liang Rui-hong , Liang Lu , Chen Jun , Liu Cheng-mei
Published: January 2019

Crude water-extracted pectin (WEP) isolated from creeping fig seeds were mainly fractionated into WEP-0.3 and WEP-0.4 fractions. Fractions were confirmed to be nonstarch, nonreducing sugars, nonpolyphenols and protein-unbounded acidic polysaccharides. Interestingly, a significant difference in solubility was found between WEP-0.3 (higher solubility than WEP) and WEP-0.4 (remarkably insoluble), which was consistent with the amorphous and porous sponge-like structure of WEP-0.3 as well as the crystalline and dense rod-like state of WEP-0.4. However, the result of the FT-IR spectra was contradicted by the solubility of WEP-0.4, which possessed the lowest degree of methoxylation and ought to possess the highest solubility. Through mineral analysis, a considerably high content of Ca2+ was found in WEP-0.4, suggesting that the low solubility of WEP-0.4 was probably attributable to the formation of microgels during dialysis. Therefore, metal divalent cations in the dialysate were suggested to be depleted for the dialysis of low methoxyl pectin.
Electrospun Graphene Nanosheet-Filled Poly(Trimethylene Terephthalate) Composite Fibers: Effects of the Graphene Nanosheet Content on Morphologies, Electrical Conductivity, Crystallization Behavior, and Mechanical Properties
Authors: Huang Chien-Lin , Wu Hsuan-Hua , Jeng Yung-Ching , Liang Wei-Zhi
Published: January 2019

In this study the effects of increased graphene nanosheet (GNS) concentration on variations in the structure and properties of electrospun GNS-filled poly(trimethylene terephthalate) (PTT/GNS) composite fiber, such as its morphologies, crystallization behavior, mechanical properties, and electrical conductivity, were investigated. The effects of GNS addition on solution rheology and conductivity were also investigated. GNSs were embedded in the fibers and formed protrusions. The PTT cold crystallization rate of PTT/GNS composite fibers increased with the gradual addition of GNSs. A PTT mesomorphic phase was formed during electrospinning, and GNSs could induce the PTT mesomorphic phase significantly during PTT/GNS composite fiber electrospinning. The PTT/GNS composite fiber mats (CFMs) became ductile with the addition of GNSs. The elastic recoveries of the PTT/GNS CFMs with 170 °C annealing were better than those of the as-spun PTT/GNS CFMs. Percolation scaling laws were applied to the magnitude of conductivity to reveal the percolation network of electrospun PTT/GNS CFMs. The electrical conductivity mechanism of the PTT/GNS CFMs differed from that of the PTT/GNS composite films. Results showed that the porous structure of the PTT CFMs influenced the performance of the mats in terms of electrical conductivity.
Simulating the Filtration Effects of Cement-Grout in Fractured Porous Media with the 3D Unified Pipe-Network Method
Authors: Sun Zizheng , Yan Xiao , Han Weiqi , Ma Guowei , Zhang Yiming
Published: January 2019

In grouting process, filtration is the retention and adsorption of cement-grout particles in a porous/fractured medium. Filtration partly/even completely blocks the transportation channels in the medium, greatly decreasing its permeability. Taking into account filtration effects is essential for accurately estimating the grout penetration region. In this paper, the 3D unified pipe-network method (UPM) is adopted for simulating 3D grout penetration process in a fractured porous medium, considering filtration effects. The grout is assumed to exhibit two-phase flow, and the filtration effects depend on not only the concentration and rheology of the grout but also the porosity and permeability of the fractured porous medium. By comparing the model with the experimental results, we firstly verify the proposed numerical model. Then sensitivity analysis is conducted, showing the influences of grout injection pressures, the water–cement ratios of grout (W/C) and the grout injection rates on filtration effect. Finally, the grout filtration process in a complex 3D fractured network is simulated, indicating that the size of the grout penetration region is limited due to filtration.
Religion as a Human Right and a Security Threat—Investigating Young Adults’ Experiences of Religion in Finland
Authors: Niemi Pia-Maria , Kallioniemi Arto , Ghosh Ratna
Published: January 2019

The emergence of religiously motivated terrorist attacks and the increasing xenophobia expressed in Europe concern religions in many ways. Questions related to religion also lie at the core of educational aims and practices used to create national cohesion and understanding about different types of values and worldviews. However, despite the topicality of the issue, we have little knowledge about the ways in which young adults experience religions in a secular state. In order to contribute to the discussion regarding the relationships between religion, nationality, security, and education, this study focuses on investigating how politically active young adults experience the role of religions in Finnish society. The qualitative data of this study were collected from young adults (18–30-year-olds) through an online questionnaire distributed through political youth organisations. The content analysis of the responses (altogether 250 respondents) identified five main orientations towards religions. The findings highlight the importance of providing young people with education about different faiths and worldviews for reducing prejudices, especially those related to Islam. The findings also highlight the need to address in education and society the possible but not as self-evident relationship between violence and religion, and to do this more explicitly than is currently done.
Mine Sited after Mine Activity: The Brownfields Methodology and Kuzbass Coal Mining Case
Authors: Cehlár Michal , Janočko Juraj , Šimková Zuzana , Pavlik Tomas , Tyulenev Maxim , Zhironkin Sergey , Gasanov Magerram
Published: January 2019

Operating life of a mine lasts from a few years to several decades. Mine closure occurs once the mineral resource is exhausted, or operations are no longer profitable. Mine closure plans are required by most regulatory agencies worldwide before a mining closure permission is granted, and must demonstrate that the site will not pose a threat to the environment and health of the society in future. The article describes a new tool, the brownfields methodology, which can help to promote the revitalization of old mining areas as a part of their technological modernization and subsoil full extraction with environmental damage reduction.
Integration and Visualization of Mineralogical and Topographical Information Derived from ASTER and DEM Data
Authors: Kurata Kana , Yamaguchi Yasushi
Published: January 2019

This paper proposes a method of combining and visualizing multiple lithological indices derived from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data and topographical information derived from digital elevation model (DEM) data in a single color image that can be easily interpreted from a geological point of view. For the purposes of mapping silicate rocks, carbonate rocks, and clay minerals in hydrothermal alteration zones, two new indices derived from ASTER thermal infrared emissivity data were developed to identify silicate rocks, and existing indices were adopted to indicate the distribution of carbonate rocks and the species and amounts of clay mineral. In addition, another new method was developed to visualize the topography from DEM data. The lithological indices and topographical information were integrated using the hue–saturation–value (HSV) color model. The resultant integrated image was evaluated by field survey and through comparison with the results of previous studies in the Cuprite and Goldfield areas, Nevada, USA. It was confirmed that the proposed method can be used to visualize geological information and that the resulting images can easily be interpreted from a geological point of view.
Distributed Scatterer InSAR Reveals Surface Motion of the Ancient Chaoshan Residence Cluster in the Lianjiang Plain, China
Authors: Liu Yuzhou , Ma Peifeng , Lin Hui , Wang Weixi , Shi Guoqiang
Published: January 2019

The Lianjiang Plain in China and ancient villages distributed within the plain are under the potential threat of surface motion change, but no effective monitoring strategy currently exists. Distributed Scatterer InSAR (DSInSAR) provides a new high-resolution method for the precise detection of surface motion change. In contrast to the first-generation of time-series InSAR methodology, the distributed scatterer-based method focuses both on pointwise targets with high phase stability and distributed targets with moderate coherence, the latter of which is more suitable for the comprehensive environment of the Lianjiang Plain. In this paper, we present the first study of surface motion change detection in the Lianjiang Plain, China. Two data stacks, including 54 and 29 images from Sentinel-1A adjacent orbits, are used to retrieve time-series surface motion changes for the Lianjiang Plain from 2015 to 2018. The consistency of measurement has been cross-validated between adjacent orbit results with a statistically significant determination coefficient of 0.92. The temporal evolution of representative measuring points indicates three subzones with varied surface patterns: Eastern Puning (Zone A) in a slight elastic rebound phase with a moderate deformation rate (0–40 mm/year), Chaonan (Zone B) in a substantial subsidence phase with a strong deformation rate (−140–0 mm/year), and Chaoyang (Zone C) in a homogeneous and stable situation (−10–10 mm/year). The spatial distribution of these zones suggests a combined change dynamic and a strong concordance of factors impacting surface motion change. Human activities, especially groundwater exploitation, dominate the subsidence pattern, and natural conditions act as a supplementary inducement by providing a hazard-prone environment. The qualitative and quantitative analysis of spatial and temporal details in this study provides a basis for systematic surface motion monitoring, cultural heritage protection and groundwater resources management.
Video Monitoring Application of CMOS 4T-PPD-APS Under γ-ray Radiation
Authors: Xu Shoulong , Zou Shuliang , Han Yongchao , Qu Yantao , Zhang Taoyi
Published: January 2019

In this paper, we discuss the potential use of four transistor active pixel sensor (4T-APS) as a video monitor at a nuclear accident site with a high level of γ radiation. The resistance and radiation responses to γ radiation were investigated by radiation experiments using 137Cs and 60Co γ-ray sources. The radiation resistance of 4T-APS was studied by testing the mean and the maximum dark current of the sensors after irradiation. A random spatial distribution of radiation response events was observed upon analyzing these events on the video images in a given time during irradiation. The background dependence of the 4T-APS was also studied by comparing the grayscale incremental value of the images with different color and grayscale backgrounds: the radiation response events were obvious on the images with a background having a smaller grayscale value or a deeper color. Finally, the color saturation and resolution of the images were tested using a vector oscilloscope and a test card. When the total ionizing dose was less than or equal to the damage threshold, no significant performance deterioration of 4T-APS was observed in an environment with sufficient light.
Wearable Potentiometric Sensors for Medical Applications
Authors: Cuartero María , Parrilla Marc , Crespo Gaston A.
Published: January 2019

Wearable potentiometric sensors have received considerable attention owing to their great potential in a wide range of physiological and clinical applications, particularly involving ion detection in sweat. Despite the significant progress in the manner that potentiometric sensors are integrated in wearable devices, in terms of materials and fabrication approaches, there is yet plenty of room for improvement in the strategy adopted for the sample collection. Essentially, this involves a fluidic sampling cell for continuous sweat analysis during sport performance or sweat accumulation via iontophoresis induction for one-spot measurements in medical settings. Even though the majority of the reported papers from the last five years describe on-body tests of wearable potentiometric sensors while the individual is practicing a physical activity, the medical utilization of these devices has been demonstrated on very few occasions and only in the context of cystic fibrosis diagnosis. In this sense, it may be important to explore the implementation of wearable potentiometric sensors into the analysis of other biofluids, such as saliva, tears and urine, as herein discussed. While the fabrication and uses of wearable potentiometric sensors vary widely, there are many common issues related to the analytical characterization of such devices that must be consciously addressed, especially in terms of sensor calibration and the validation of on-body measurements. After the assessment of key wearable potentiometric sensors reported over the last five years, with particular attention paid to those for medical applications, the present review offers tentative guidance regarding the characterization of analytical performance as well as analytical and clinical validations, thereby aiming at generating debate in the scientific community to allow for the establishment of well-conceived protocols.
A Comprehensive Study of the Potential Application of Flying Ethylene-Sensitive Sensors for Ripeness Detection in Apple Orchards
Authors: Valente João , Almeida Rodrigo , Kooistra Lammert
Published: January 2019

The right moment to harvest apples in fruit orchards is still decided after persistent monitoring of the fruit orchards via local inspection and using manual instrumentation. However, this task is tedious, time consuming, and requires costly human effort because of the manual work that is necessary to sample large orchard parcels. The sensor miniaturization and the advances in gas detection technology have increased the usage of gas sensors and detectors in many industrial applications. This work explores the combination of small-sized sensors under Unmanned Aerial Vehicles (UAV) to understand its suitability for ethylene sensing in an apple orchard. To accomplish this goal, a simulated environment built from field data was used to understand the spatial distribution of ethylene when subject to the orchard environment and the wind of the UAV rotors. The simulation results indicate the main driving variables of the ethylene emission. Additionally, preliminary field tests are also reported. It was demonstrated that the minimum sensing wind speed cut-off is 2 ms−1 and that a small commercial UAV (like Phantom 3 Professional) can sense volatile ethylene at less than six meters from the ground with a detection probability of a maximum of 10 % . This work is a step forward in the usage of aerial remote sensing technology to detect the optimal harvest time.
Sensitivity of a Ratio Vegetation Index Derived from Hyperspectral Remote Sensing to the Brown Planthopper Stress on Rice Plants
Authors: Tan Ye , Sun Jia-Yi , Zhang Bing , Chen Meng , Liu Yu , Liu Xiang-Dong
Published: January 2019

Remote sensing end-products related to vegetation have potential applications in monitoring the health of crops. The sensitivity of a spectral index to crop stress determines its application prospect. Our aim in this study was to explore the sensitivity of a ratio vegetation index (RVI) to identify the damage caused by brown planthoppers (BPHs) on rice plants, and to evaluate the potential application of hyperspectral end-products to monitor population size of BPH. Different numbers of the second-instar nymphs were released onto potted rice at the tillering stage. The plants were exposed to BPH for two, four, six, and eight days, and reflectance from the damaged rice was measured using a hyperspectral spectroradiometer. Measurements were done again two, four, and six days after exposure (recover days), and then the spectral index RVI746/670 was compared among rice plants infested with different numbers of BPH. The relationships between RVI746/670, the number of BPH and exposure day were simulated by linear and curve models. BPH damage resulted in a decreased spectral index RVI746/670 of rice plants. RVI746/670 well indicated the damage of rice plants caused by six–eight BPH nymphs per plant in six–eight days, but the index could not identify the damage of these nymphs in two days. The RVI746/670 showed a two–four-day delay to indicate a slight BPH damage. The spectral index RVI746/670 could indicate the physiologic compensation of plants for the feeding of BPH and the post-effect of BPH damage on rice. The RVI746/670 of rice showed a quadratic curve relation with the number of BPH nymphs and a quadratic or linear relation with the exposure day. The recover day had no significant effects on RVI746/670. The RVI746/670 (Y) could be simulated by a quadratic surface model based on the number of BPH (N) and exposure day (T): Y = 3.09427 + 0.59111T + 0.44296N − 0.03683T2 − 0.03035N2 − 0.08188NT (R2 = 0.5228, p < 0.01). In summary, the spectral index RVI746/670 of rice is sensitive to damage caused by BPH.
Design of Acoustical Bessel-Like Beam Formation by a Pupil Masked Soret Zone Plate Lens
Authors: Tarrazó-Serrano Daniel , Castiñeira-Ibáñez Sergio , Minin Oleg V. , Candelas Pilar , Rubio Constanza , Minin Igor V.
Published: January 2019

The image performance of acoustic and ultrasound sensors depends on several fundamental parameters such as depth of focus or lateral resolution. There are currently two different types of acoustic diffractive lenses: those that form a diffraction-limited spot with a shallow depth of focus (zone plates) and lenses that form an extended focus (quasi-Bessel beams). In this paper, we investigate a pupil-masked Soret zone plate, which allows the tunability of a normalized angular spectrum. It is shown that the depth of focus and the lateral resolution can be modified, without changing the lens structure, by choosing the size of the pupil mask. This effect is based on the transformation of spherically-converging waves into quasi-conical waves, due to the apodization of the central part of the zone plate. The theoretical analysis is verified with both numerical simulations and experimental measurements. A Soret zone plate immersed in water with D/2F = 2.5 and F = 4.5 λ changes its depth of focus from 2.84 λ to 5.9 λ and the lateral resolution increases from 0.81 λ to 0.64 λ at a frequency of 250 kHz, by modifying the pupil mask dimensions of the Soret zone plate.
Engagement to Enhance Community: An Example of Extension’s Land-Grant Mission in Action
Authors: Burkhart-Kriesel Cheryl , Weigle Jason L. , Hawkins Jennifer
Published: January 2019

Engagement is a foundational practice for the Extension systems of land-grant universities and is demonstrated through its’ work in partnership with individuals, organizations and communities. This article will share how an Extension-led effort, focused on an aspect of community development, integrated several components of engagement starting with the initial conversation through the evaluation process. Practitioner reflections on two examples that occurred in different states will highlight the processes and tools that helped nurture engagement between faculty and community and support the development of a sustainable and resilient community. The multi-state implementation will illustrate the unique depth and breadth of public participation that can be achieved when academic institutions are focused on engagement to strengthen communities.
Crowd Logistics Platform’s Informative Support to Logistics Performance: Scale Development and Empirical Examination
Authors: Zhang Mingyu , Xia Yuhuan , Li Shuang , Wu Wenbing , Wang Shuxiang
Published: January 2019

Using the organization information processing theory, we explored the process through which the informative support of crowd logistics platforms affects logistics performance. After collecting data from 321 respondents from two crowd logistics companies in China, we proposed and tested the theoretical framework empirically using SEM. To conduct the empirical study, we developed scales for platform’s informative support and the degree of logistics resources-demand match, respectively. The results indicate that a platform’s informative support improves logistics performance via two mediators, i.e., logistics resources-demand match and logistics agility. Moreover, a platform’s ease of use moderates the indirect process through which its informative support promotes logistics performance via logistics resources-demand match. However, a platform’s ease of use has no significant effect on the indirect process of its informative support affecting logistics performance via logistics agility. This paper extends our understanding on how the informative support of crowd logistics platforms predicts logistics performance.
Impacts of Green Production Decision on Social Welfare
Authors: Zhang Zheng , Wang Yingtong , Meng Qingchun , Luan Xinyang
Published: January 2019

As an important approach of achieving sustainable development, green production plays a significant role in improving the ecological environment and total social welfare. In order to clarify the impacts of green production on social welfare favorably, this paper assumes that there are two types of consumers in the market: the green and the brown. Green consumers have green preference, focusing on the environmental and physical attributes of products; while brown consumers only value the physical attributes. We have obtained some intriguing conclusions through the use of the Hotelling model, as follows: (i) The total social welfare will benefit from green production. Meanwhile, we also find that the social welfare is likely to reach the highest value in scenario BG (i.e., both enterprises implement green production) or scenario SG (i.e., only one enterprise implements green production). (ii) Moreover, the total social welfare is always positively related to the degree of consumer green preference and unit of environmental benefit parameters in scenario SG and scenario BG. (iii) Finally, in scenario BG, the proportion of green consumers has a positive effect on the total social welfare, while only when certain conditions are satisfied, the higher proportion of green consumers will benefit the social welfare in scenario SG. Our findings can provide useful managerial insights for policy-makers in the development of green production.
Sustainability Development in Mathematics Education—A Case Study of What Kind of Meanings Do Prospective Class Teachers Find for the Mathematical Symbol “23”?
Authors: Joutsenlahti Jorma , Perkkilä Päivi
Published: January 2019

In this article, our focus is on sustainable development in mathematics education from the point of view of teacher training. The aim was to develop prospective teachers’ content knowledge and pedagogical content knowledge of school mathematics. As a case study, we chose the mathematical symbol “a/b”, and examined how prospective class teachers in Finland connect it to the concepts of fraction, ratio, division, rational number or probability. Mathematics textbooks often have a central role in lessons, and they affect strongly how pupils understand concepts and the relationships between them. We chose languaging as a multi-semiotic approach to interpreting what kind of meanings the prospective class teachers gave the mathematical symbol “a/b”. The results show that some of these concepts are difficult to see at the same time from the given mathematical symbol. The concept of ratio is particularly difficult for prospective class teachers to interpret. Pictorial presentation supported the interpretations. Mathematics learning materials and teacher education should develop in accordance with the results of the study.
Exploring “Company Personas” for Informing Design for Sustainability Implementation in Companies
Authors: Ali Faheem , Stewart Raphaëlle , Boks Casper , Bey Niki
Published: January 2019

The need for understanding the context of the case company during Design for Sustainability (DfS) implementation has been a long identified need among the researchers in the field. Yet, studies on company context have primarily focused on studying, enlisting, and prescribing standardized solutions for companies or clustering companies based on similarities. Such approaches have not been able to overcome the organizational “soft side” challenges that have been long addressed in DfS literature. This explorative paper takes insights from 20 case interviews conducted in Norwegian and Danish manufacturing companies and with sustainability experts and uses the concept of persona from design studies to explore the potential of defining “company personas” to better define the context of the company. The interview analysis produced 14 dimensions, including both hitherto identified factual needs of companies and soft-side elements required to create a company persona, thereby informing practitioners and researchers to take a DfS implementation approach tailored to the company context.
Developing the Romanian Organic Market: A Producer’s Perspective
Authors: Popa Iulia Diana , Dabija Dan-Cristian
Published: January 2019

Romania’s organic market increasingly resembles its Western counterparts: a vegetarian diet, disease prevention through consumption of organic food produced according to specific standards, preferring quality over quantity—all relevant factors influencing purchasing behaviour. It is the task of consumerist organisations to educate consumers on the benefits of the above factors, a process influenced by social and cultural trends, experience, lifestyle, motivations and preferences. The market is attractive to domestic producers offering an increasing assortment of organic food types. This paper aims to highlight the most relevant features of the rapidly expanding Romanian organic market from the perspective of organic producers. To this effect, it reviews the literature dealing with the main factors influencing consumer behaviour and attitudes. The qualitative research among producers reveals strategic directions pursued in order to understand and adapt to market characteristics and dynamics. The results allow better understanding of organic consumers’ behaviour in the emerging markets and highlight strategies to increase market success. Healthy lifestyle, desire to protect the environment, product quality and attractive prices are all important factors determining consumption of organic products. Whilst aware of these factors, producers point to the lack of education for developing an organic mentality and identifying organic products, poor distribution of products and lack of financial support across the entire logistics chain.
Place vs. Node Transit: Planning Policies Revisited
Authors: Olaru Doina , Moncrieff Simon , McCarney Gary , Sun Yuchao , Reed Tristan , Pattison Cate , Smith Brett , Biermann Sharon
Published: January 2019

A core contemporary planning approach is the promotion of transit-oriented developments (TODs) and in recent times cities have committed substantial financial investment to encourage sustainable precincts around public transport. Evaluation of the success of TODs is key for continuing the planning efforts. A frequently applied framework for characterizing TODs draws on Bertolini’s Node-Place (N-P) model, enriched through application in various contexts. We offer here an extension to the N-P model, using a case study in a low-density city, Perth, Western Australia. A typology of railway stations is developed using 43 indicators and then linear models are applied to ascertain the association between patronage and station precinct features. The results show that various types of measures are required to increase public transport ridership for the four clusters that emerged from the analysis. Density alone does not lead to increased use of public transport; it must be associated with city-wide accessibility, as well as access/egress to and from the station.
Stability Analysis of Surrounding Rock in Paste Backfill Recovery of Residual Room Pillars
Authors: Zhou Nan , Yan Hao , Jiang Shuyin , Sun Qiang , Ouyang Shenyang
Published: January 2019

A method of paste backfill recovery for residual room coal pillars is hereby proposed. The principles and processes of this method are systemically explained to address issues such as mining-induced earthquakes from spontaneous destabilization, surface subsidence, and low recovery rates. These are caused by the instability of residual coal pillars due to their spontaneous combustion in room-and-pillar mining in medium-to-small coalmines in the northern Shaanxi area. This method is based on the local abundance of surface aeolian sand and solid wastes to be used as paste-backfilling materials in coalmines in the northern Shaanxi area. Uniaxial compressive strength, bleeding rate, and slump tests were performed on paste-backfilled samples constituted at different ratios based on the types of materials involved in paste backfilling in the northern Shaanxi region, thereby helping to confirm the optimal ratios for paste-backfilling materials for the Ershike coal mine. A simulation was conducted to investigate the failure, goaf vertical stress distribution, and surface deformation properties of paste-backfilled pillars and coal pillars, where paste backfilling was used with paste-backfilling materials constituted at different compressive strengths. This was to verify the experimental results that would be obtained with paste-backfilling materials constituted at different ratios, and reveal the mechanism by which paste backfilling of residual room pillars can maintain the mine’s surrounding rock stability. These study results are of great instructive significance to the safe recovery of residual room pillars in China’s western mining areas.
Symmetric Face Normalization
Authors: Su Ya , Liu Zhe , Ban Xiaojuan
Published: January 2019

Image registration is an important process in image processing which is used to improve the performance of computer vision related tasks. In this paper, a novel self-registration method, namely symmetric face normalization (SFN) algorithm, is proposed. There are three contributions in this paper. Firstly, a self-normalization algorithm for face images is proposed, which normalizes a face image to be reflection symmetric horizontally. It has the advantage that no face model needs to be built, which is always severely time-consuming. Moreover, it can be considered as a pre-processing procedure which greatly decreases the parameters needed to be adjusted. Secondly, an iterative algorithm is designed to solve the self-normalization algorithm. Finally, SFN is applied to the between-image alignment problem, which results in the symmetric face alignment (SFA) algorithm. Experiments performed on face databases show that the accuracy of SFN is higher than 0.95 when the translation on the x-axis is lower than 15 pixels, or the rotation angle is lower than 18°. Moreover, the proposed SFA outperforms the state-of-the-art between-image alignment algorithm in efficiency (about four times) without loss of accuracy.
Inspired by Human Eye: Vestibular Ocular Reflex Based Gimbal Camera Movement to Minimize Viewpoint Changes
Authors: B. Adithya , B. N. Pavan Kumar , Chai Young Ho , Patil Ashok Kumar
Published: January 2019

Human eyeballs move relative to the head, resulting in optimal changes in the viewpoint. We tested similar vestibular ocular reflex (VOR)-based movement on Zenmuse-X3 gimbal camera relative to pre-defined YAW movements of the DJI Matrice-100 unmanned aerial vehicle (UAV). Changes in viewpoint have various consequences for visual and graphical rendering. Therefore, this study investigated how to minimize these changes. OpenGL visualization was performed to simulate and measure viewpoint changes using the proposed VOR-based eyeball movement algorithm and compared with results of VOR based gimbal movement. The gimbal camera was setup to render images (scenes) on flat monitors. Positions of pre-fixed targets in the images were used to measure the viewpoint changes. The proposed approach could successfully control and significantly reduce the viewpoint changes and stabilize the image to improve visual tracking of targets on flat monitors. The proposed method can also be used to render real-time camera feed to a head-mounted display (HMD) in an ergonomically pleasing way.
Local Convergence of a Family of Weighted-Newton Methods
Authors: Behl Ramandeep , K. Argyros Ioannis , Machado J.A. , Alshomrani Ali
Published: January 2019

This article considers the fourth-order family of weighted-Newton methods. It provides the range of initial guesses that ensure the convergence. The analysis is given for Banach space-valued mappings, and the hypotheses involve the derivative of order one. The convergence radius, error estimations, and results on uniqueness also depend on this derivative. The scope of application of the method is extended, since no derivatives of higher order are required as in previous works. Finally, we demonstrate the applicability of the proposed method in real-life problems and discuss a case where previous studies cannot be adopted.
Some Results on the Symmetric Representation of the Generalized Drazin Inverse in a Banach Algebra
Authors: Qin Yonghui , Liu Xiaoji , Benítez Julio
Published: January 2019

Based on the conditions a b 2 = 0 and b π ( a b ) ∈ A d , we derive that ( a b ) n , ( b a ) n , and a b + b a are all generalized Drazin invertible in a Banach algebra A , where n ∈ N and a and b are elements of A . By using these results, some results on the symmetry representations for the generalized Drazin inverse of a b + b a are given. We also consider that additive properties for the generalized Drazin inverse of the sum a + b .
Singularities for One-Parameter Developable Surfaces of Curves
Authors: Zhao Qiming , Pei Donghe , Wang Yongqiao
Published: January 2019

Developable surfaces, which are important objects of study, have attracted a lot of attention from many mathematicians. In this paper, we study the geometric properties of one-parameter developable surfaces associated with regular curves. According to singularity theory, the generic singularities of these developable surfaces are classified—they are swallowtails and cuspidal edges. In addition, we give some examples of developable surfaces which have symmetric singularity models.
Regulatory Limits to Corporate Sustainability: How Climate Change Law and Energy Reforms in Mexico May Impair Sustainability Practices in Mexican Firms
Authors: Lloret Antonio , Domenge Rogerio , Castro-Hernández Mildred
Published: January 2019

This paper aims to show that sustainable behavior by firms may be impaired by regulatory restrictions. We challenge the assumption that regulation aimed at curbing greenhouse gas emissions (GHG) in the form of a target to meet the Country’s GHG emissions commitments will promote sustainable corporations. We argue that, in fact, such regulation may impair sustainability practices because it creates unintended consequences. This paper tackles the efficiency of the institutional framework chosen through the lenses of the analytical themes of fit, scale, and interplay, then we use a systems dynamic approach to represent how regulation in the arenas of energy efficiency and GHG emissions reduction may withhold competitive business outcomes and corporate sustainability schemes. We exemplify and simulate a single regulation scheme: a clean energy target for firms; and found that as a result of such scheme, the system is dominated by negative feedback processes resulting in lesser outcomes that would be better tackled by firms not being subject to the restrictions imposed by the regulation.
Trace Element Uptake by Herbaceous Plants from the Soils at a Multiple Trace Element-Contaminated Site
Authors: Nworie Obinna Elijah , Qin Junhao , Lin Chuxia
Published: January 2019

The uptake of trace elements by wild herbaceous plants in a multiple trace element-contaminated site was investigated. The bioaccumulation factor (BF) of trace elements was markedly variable among the different plant species. On average, the BF for various trace elements was in the following decreasing order: Zn > Cu > Mn > Ni > As > Pb > Cr. The translocation factor among the investigated plant species was also considerably variable and showed the following decreasing order: Mn > Zn > Ni > Cu > Cr > As > Pb. Several hyperaccumulating plants were identified: Artemisia vulgaris for As, Mn and Zn, Phalaris arundinacea for Mn and Ni, Heracleum sphondylium for Cr and Zn, and Bistorta officinalis for Mn and Zn. The marked accumulation of trace elements in the plant tissue suggests that the site may not be suitable for urban agricultural production. The plant tissue-borne trace elements could affect microbial activities and consequently interfere with the ecosystem functioning in the affected areas.
Monitoring the Disulfide Bonds of Folding Isomers of Synthetic CTX A3 Polypeptide Using MS-Based Technology
Authors: Huang Sheng-Yu , Wei Tin-Yu , Liu Bing-Shin , Lin Min-Han , Chiang Sheng-Kuo , Chen Sung-Fang , Sung Wang-Chou
Published: January 2019

Native disulfide formation is crucial to the process of disulfide-rich protein folding in vitro. As such, analysis of the disulfide bonds can be used to track the process of the folding reaction; however, the diverse structural isomers interfere with characterization due to the non-native disulfide linkages. Previously, a mass spectrometry (MS) based platform coupled with peptide dimethylation and an automatic disulfide bond searching engine demonstrated the potential to screen disulfide-linked peptides for the unambiguous assignment of paired cysteine residues of toxin components in cobra venom. The developed MS-based platform was evaluated to analyze the disulfide bonds of structural isomers during the folding reaction of synthetic cardiotoxin A3 polypeptide (syn-CTX A3), an important medical component in cobra venom. Through application of this work flow, a total of 13 disulfide-linked peptides were repeatedly identified across the folding reaction, and two of them were found to contain cysteine pairings, like those found in native CTX A3. Quantitative analysis of these disulfide-linked peptides showed the occurrence of a progressive disulfide rearrangement that generates a native disulfide bond pattern on syn-CTX A3 folded protein. The formation of these syn-CTX A3 folded protein reaches a steady level in the late stage of the folding reaction. Biophysical and cell-based assays showed that the collected syn-CTX A3 folded protein have a β-sheet secondary structure and cytotoxic activity similar to that of native CTX A3. In addition, the immunization of the syn-CTX A3 folded proteins could induce neutralization antibodies against the cytotoxic activity of native CTX A3. In contrast, these structure activities were poorly observed in the other folded isomers with non-native disulfide bonds. The study highlights the ability of the developed MS platform to assay isomers with heterogeneous disulfide bonds, providing insight into the folding mechanism of the bioactive protein generation.
Phylodynamic Analysis of Ebola Virus Disease Transmission in Sierra Leone
Authors: Jansen van Vuren Petrus , Ladner Jason T. , Grobbelaar Antoinette A. , Wiley Michael R. , Lovett Sean , Allam Mushal , Ismail Arshad , le Roux Chantel , Weyer Jacqueline , Moolla Naazneen , Storm Nadia , Kgaladi Joe , Sanchez-Lockhart Mariano , Conteh Ousman , Palacios Gustavo , Paweska Janusz T.
Published: January 2019

We generated genome sequences from 218 cases of Ebola virus disease (EVD) in Sierra Leone (SLE) during 2014–2015 to complement available datasets, particularly by including cases from a period of low sequence coverage during peak transmission of Ebola virus (EBOV) in the highly-affected Western Area division of SLE. The combined dataset was utilized to produce phylogenetic and phylodynamic inferences, to study sink–source dynamics and virus dispersal from highly-populated transmission hotspots. We identified four districts in SLE where EBOV was introduced and transmission occurred without onward exportation to other districts. We also identified six districts that substantially contributed to the dispersal of the virus and prolonged the EVD outbreak: five of these served as major hubs, with lots of movement in and out, and one acted primarily as a source, exporting the virus to other areas of the country. Positive correlations between case numbers, inter-district transition events, and district population sizes reaffirm that population size was a driver of EBOV transmission dynamics in SLE. The data presented here confirm the role of urban hubs in virus dispersal and of a delayed laboratory response in the expansion and perpetuation of the EVD outbreak in SLE.