bluuebunny/crossref_metadata_2025 huggingface dataset:
Mapping Heavy Metal Concentrations in Beach Sands Using GIS and Portable XRF Data
Authors: Kim Sung-Min , Choi Yosoon
Published: February 2019

It is necessary to investigate the contamination of beach sands to ensure water safety, as they may contain potentially toxic trace elements. Tourists, oil spills, or replenishing sands can cause beach sand contamination. In this study, heavy metal contamination maps of lead (Pb) and zinc (Zn) were created for Wolpo Beach, on the eastern coast of Korea, using portable X-ray fluorescence and geographic information systems (GIS). Interpolation methods, such as kriging and inverse distance weighting, were used in this study and their results were compared. Understanding the spatial variation of potentially toxic trace elements in beach sand is necessary to determine suitable measures for preventing contamination. Sufficient sand data for understanding spatial patterns can be acquired by using rapid portable X-ray fluorescence analysis. As a result, we could create heavy metal concentration maps for the sand of Wolpo Beach. It was confirmed that the southern part of the target area is more contaminated than the northern part. However, there are no sand areas with highly concentrated heavy metal levels. In addition, no sample data exceed the soil contamination standards. This study demonstrates that portable X-ray fluorescence and geographic information systems can be utilized for investigating and preventing the contamination of beach sands by creating heavy metal concentration maps.
Quantification of the Photocatalytic Self-Cleaning Ability of Non-Transparent Materials
Authors: Minella Marco , Minero Claudio
Published: February 2019

The photo-induced reactivity of compounds at the surface of photocatalytic materials is used to maintain the cleanliness of the surface of glass, concretes and paints. A standard method to quantify the photocatalytic self-cleaning (SC) properties of non-transparent materials was recently published. It is based on the covering of the sample surface with a defined amount of dye and on the evaluation of the reflectance spectra of the coloured surface under irradiation. The calibration of the spectral changes allowed the quantification of the surface residual dye and the evaluation of the self-cleaning kinetics. The method was tested on seven white and coloured photocatalytic materials using methylene blue (MB), rhodamine B (RhB) and metanil yellow (MY). The main by-products of the MB photocatalytic degradation at the solid/solid interface were identified, showing that MB degradation in solution follows a path quite different from that at the solid/solid interface. Also MY showed a different order of photoreactivity. Furthermore, experiments at the solid/solid interface are more trustworthy than tests in solution for evaluating the self-cleaning ability. The differences of the photocatalytic phenomena at the solid/solid interface in comparison with the most studied photoactivated processes at the solid/liquid interface are outlined. Furthermore, photocatalytic materials showed selectivity toward some specific dyes. This encourages the use of more than one dye for the evaluation of the self-cleaning ability of a photocatalytic material.
Rate-Type Age-Dependent Constitutive Formulation of Concrete Loaded at an Early Age
Authors: Kim Seung-Gyu , Park Yeong-Seong , Lee Yong-Hak
Published: February 2019

A general formulation framework for an age-dependent constitutive equation of concrete is presented to account for the development of the elastic modulus at an early age. This is achieved by expanding the total stress vs. strain relation with respect to the time-varying elastic modulus. Two types of constitutive formulation frameworks are derived depending on whether (or not) the time-varying effect of the elastic modulus was taken into account in the linearized series expansion. The causes for the age-dependent deformations under sustained loads are defined in the formulation based on the two internal mechanisms of delayed elasticity and the ageing phenomenon. The ageing phenomenon is incorporated in a conventional delayed strain concept in terms of the variable elastic modulus with time. Four cases of age-dependent constitutive equations are formulated within the presented formulation framework by employing different types of creep models. The mechanical characteristics of the terms that comprise the various constitutive equations are examined and compared. Numerical application of the time-dependent test results of cylindrical specimens indicate that the creep formulation that considered the elastic modulus development showed a good agreement with the experimental result while the formulation that did not consider the elastic modulus development underestimated the result by 15%.
Advanced Mechanical Strength in Post Heat Treated SLM 2507 at Room and High Temperature Promoted by Hard/Ductile Sigma Precipitates
Authors: Saeidi Kamran , Alvi Sajid , Lofaj Frantisek , Petkov Valeri Ivanov , Akhtar Farid
Published: February 2019

Duplex stainless steel, 71 wt.% austenite, 13 wt.% ferrite and 16 wt.% sigma, was made upon heat treating of fully ferritic as-built selective laser melted (SLM) 2507 stainless steel at 1200 °C. Formation of sigma phase in the heat treated SLM 2507 was investigated using optical microscopy and scanning electron microscopy (SEM). The heat treated SLM 2507 demonstrated a yield strength of 686 MPa, ultimate tensile strength of 920 MPa and an elongation of 1.8% at room temperature with a brittle fracture morphology. Precipitation of sigma phase during heat treatment and slow cooling improved the mechanical and wear properties at high temperatures (1200 °C and 800 °C, respectively). The tensile strength and elongation of the heat treated SLM 2507 was measured 400 MPa and 20% as compared to casted duplex steel with 19 MPa and 30% elongation at 1200 °C. The 20 times higher mechanical strength as compared to casted duplex steel was attributed to sigma precipitates. Tribological behaviour of heat treated duplex SLM 2507 containing sigma at 800 °C showed very low wear rate of 4.5 × 10−5 mm3/mN compared to casted duplex steel with 1.6 × 10−4 mm3/mN.
The β-N-Acetylhexosaminidase in the Synthesis of Bioactive Glycans: Protein and Reaction Engineering
Authors: Bojarová Pavla , Kulik Natalia , Hovorková Michaela , Slámová Kristýna , Pelantová Helena , Křen Vladimír
Published: February 2019

N-Acetylhexosamine oligosaccharides terminated with GalNAc act as selective ligands of galectin-3, a biomedically important human lectin. Their synthesis can be accomplished by β-N-acetylhexosaminidases (EC 3.2.1.52). Advantageously, these enzymes tolerate the presence of functional groups in the substrate molecule, such as the thiourea linker useful for covalent conjugation of glycans to a multivalent carrier, affording glyconjugates. β-N-Acetylhexosaminidases exhibit activity towards both N-acetylglucosamine (GlcNAc) and N-acetylgalactosamine (GalNAc) moieties. A point mutation of active-site amino acid Tyr into other amino acid residues, especially Phe, His, and Asn, has previously been shown to strongly suppress the hydrolytic activity of β-N-acetylhexosaminidases, creating enzymatic synthetic engines. In the present work, we demonstrate that Tyr470 is an important mutation hotspot for altering the ratio of GlcNAcase/GalNAcase activity, resulting in mutant enzymes with varying affinity to GlcNAc/GalNAc substrates. The enzyme selectivity may additionally be manipulated by altering the reaction medium upon changing pH or adding selected organic co-solvents. As a result, we are able to fine-tune the β-N-acetylhexosaminidase affinity and selectivity, resulting in a high-yield production of the functionalized GalNAcβ4GlcNAc disaccharide, a selective ligand of galectin-3.
One-Pot Synthesis of Triazolobenzodiazepines Through Decarboxylative [3 + 2] Cycloaddition of Nonstabilized Azomethine Ylides and Cu-Free Click Reactions
Authors: Ma Xiaoming , Zhang Xiaofeng , Qiu Weiqi , Zhang Wensheng , Wan Bruce , Evans Jason , Zhang Wei
Published: February 2019

A one-pot synthesis of triazolobenzodiazepine-containing polycyclic compounds is introduced. The reaction process involves a decarboxylative three-component [3 + 2] cycloaddition of nonstabilized azomethine ylides, N-propargylation, and intramolecular click reactions.
Hydrogels and Their Applications in Targeted Drug Delivery
Authors: Narayanaswamy Radhika , Torchilin Vladimir P.
Published: February 2019

Conventional drug delivery approaches are plagued by issues pertaining to systemic toxicity and repeated dosing. Hydrogels offer convenient drug delivery vehicles to ensure these disadvantages are minimized and the therapeutic benefits from the drug are optimized. With exquisitely tunable physical properties that confer them great controlled drug release features and the merits they offer for labile drug protection from degradation, hydrogels emerge as very efficient drug delivery systems. The versatility and diversity of the hydrogels extend their applications beyond targeted drug delivery also to wound dressings, contact lenses and tissue engineering to name but a few. They are 90% water, and highly porous to accommodate drugs for delivery and facilitate controlled release. Herein we discuss hydrogels and how they could be manipulated for targeted drug delivery applications. Suitable examples from the literature are provided that support the recent advancements of hydrogels in targeted drug delivery in diverse disease areas and how they could be suitably modified in very different ways for achieving significant impact in targeted drug delivery. With their enormous amenability to modification, hydrogels serve as promising delivery vehicles of therapeutic molecules in several disease conditions, including cancer and diabetes.
Electrospun Antimicrobial Films of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Containing Eugenol Essential Oil Encapsulated in Mesoporous Silica Nanoparticles
Authors: Melendez-Rodriguez Beatriz , Figueroa-Lopez Kelly J. , Bernardos Andrea , Martínez-Máñez Ramón , Cabedo Luis , Torres-Giner Sergio , M. Lagaron Jose
Published: February 2019

The main goal of this study was to develop poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) films with long-term antimicrobial capacity of interest in food packaging applications. To this end, eugenol was first highly efficiently encapsulated at 50 wt.-% in the pores of mesoporous silica nanoparticles by vapor adsorption. The eugenol-containing nanoparticles were then loaded in the 2.5–20 wt.-% range into PHBV by electrospinning and the resultant electrospun composite fibers were annealed at 155 °C to produce continuous films. The characterization showed that the PHBV films filled with mesoporous silica nanoparticles containing eugenol present sufficient thermal resistance and enhanced mechanical strength and barrier performance to water vapor and limonene. The antimicrobial activity of the films was also evaluated against foodborne bacteria for 15 days in open vs. closed conditions in order to simulate real packaging conditions. The electrospun PHBV films with loadings above 10 wt.-% of mesoporous silica nanoparticles containing eugenol successfully inhibited the bacterial growth, whereas the active films stored in hermetically closed systems increased their antimicrobial activity after 15 days due to the volatile portion accumulated in the system’s headspace and the sustained release capacity of the films. The resultant biopolymer films are, therefore, potential candidates to be applied in active food packaging applications to provide shelf life extension and food safety.
Intracellular Imaging with Genetically Encoded RNA-Based Molecular Sensors
Authors: Sun Zhining , Nguyen Tony , McAuliffe Kathleen , You Mingxu
Published: February 2019

Genetically encodable sensors have been widely used in the detection of intracellular molecules ranging from metal ions and metabolites to nucleic acids and proteins. These biosensors are capable of monitoring in real-time the cellular levels, locations, and cell-to-cell variations of the target compounds in living systems. Traditionally, the majority of these sensors have been developed based on fluorescent proteins. As an exciting alternative, genetically encoded RNA-based molecular sensors (GERMS) have emerged over the past few years for the intracellular imaging and detection of various biological targets. In view of their ability for the general detection of a wide range of target analytes, and the modular and simple design principle, GERMS are becoming a popular choice for intracellular analysis. In this review, we summarize different design principles of GERMS based on various RNA recognition modules, transducer modules, and reporting systems. Some recent advances in the application of GERMS for intracellular imaging are also discussed. With further improvement in biostability, sensitivity, and robustness, GERMS can potentially be widely used in cell biology and biotechnology.
Impaired Skeletal Muscle Branched-Chain Amino Acids Catabolism Contributes to Their Increased Circulating Levels in a Non-Obese Insulin-Resistant Fructose-Fed Rat Model
Authors: David Jérémie , Dardevet Dominique , Mosoni Laurent , Savary-Auzeloux Isabelle , Polakof Sergio
Published: February 2019

Elevated plasma branched-chain amino acids (BCAA) levels are often observed in obese insulin-resistant (IR) subjects and laboratory animals. A reduced capacity of the adipose tissues (AT) to catabolize BCAA has been proposed as an explanation, but it seems restricted to obesity models of genetically modified or high fat–fed rodents. We aimed to determine if plasma BCAA levels were increased in a model of IR without obesity and to explore the underlying mechanisms. Rats were fed with a standard diet, containing either starch or fructose. BCAA levels, body weight and composition were recorded before and after 5, 12, 30, or 45 days of feeding. Elevated blood BCAA levels were observed in our IR model with unaltered body weight and composition. No changes were observed in the liver or the AT, but instead an impaired capacity of the skeletal muscle to catabolize BCAA was observed, including reduced capacity for transamination and oxidative deamination. Although the elevated blood BCAA levels in the fructose-fed rat seem to be a common feature of the IR phenotype observed in obese subjects and high fat–fed animals, the mechanisms involved in such a metabolic phenomenon are different, likely involving the skeletal muscle BCAA metabolism.
Mechanism and Potential of Egg Consumption and Egg Bioactive Components on Type-2 Diabetes
Authors: Wang Xiaofeng , Son Myoungjin , Meram Chalamaiah , Wu Jianping
Published: February 2019

Type-2 diabetes (T2D) is one of the major global health challenges and a substantial economic burden. Egg and egg-derived components have been indicated to possess antioxidant, anti-inflammatory, anti-hypertensive, immunomodulatory, and anti-cancer activities. However, the scientific evidence about the benefits of egg on T2D is debatable. The relationship between egg consumption and the risk of T2D from observational epidemiological studies is not consistent. Interventional clinical studies, however, provide promising evidence that egg consumption ameliorates the risk of T2D. Current research progress also indicates that some egg components and egg-derived peptides might be beneficial in the context of T2D, in terms of insulin secretion and sensitivity, oxidative stress, and inflammation, suggesting possible application on T2D management. The current review summarizes recent clinical investigations related to the influence of egg consumption on T2D risk and in vivo and in vitro studies on the effect and mechanism of egg components and egg-derived peptides on T2D.
pH-Sensitive Polyampholyte Microgels of Poly(Acrylic Acid-co-Vinylamine) as Injectable Hydrogel for Controlled Drug Release
Authors: Chen Yanmin , Sun Peijian
Published: February 2019

pH-sensitive polyampholyte microgels of poly(acrylic acid-co-vinylamine) (P(AA-co-VAm)) were developed as an injectable hydrogel for controlled drug release. The microgels of P(AA-co-VAm) were prepared via inverse suspension polymerization of acrylic acid and N-vinylformamide followed by hydrolysis of poly(N-vinylformamide) (PNVF) chains of the resultant microgels under basic condition. The pH-sensitivity of the P(AA-co-VAm) microgels in zeta potential and swelling ratio were investigated using a zeta potential analyzer and optical microscope. The results showed that both the zeta potential and the swelling ratio of the microgels were highly affected by the solution pH. By changing the pH of P(AA-co-VAm) microgel dispersion, the interparticle interaction and the swelling ratio of the microgels could be well adjusted and a colloidal hydrogel could be fabricated at moderate pH, showing a pH-triggered reversible fluid-gel transition. Using the polyampholyte P(AA-co-VAm) microgels as an injectable hydrogel drug release system, a sustained drug release could be achieved, indicating the great potentials of the pH-sensitive P(AA-co-VAm) microgels for controlled drug delivery.
Highly Selective Copper Ion Imprinted Clay/Polymer Nanocomposites Prepared by Visible Light Initiated Radical Photopolymerization
Authors: Msaadi Radhia , Yilmaz Gorkem , Allushi Andrit , Hamadi Sena , Ammar Salah , Chehimi Mohamed M. , Yagci Yusuf
Published: February 2019

There is an urgent demand worldwide for the development of highly selective adsorbents and sensors of heavy metal ions and other organic pollutants. Within these environmental and public health frameworks, we are combining the salient features of clays and chelatant polymers to design selective metal ion adsorbents. Towards this end, the ion imprinting approach has been used to develop a novel nanohybrid material for the selective separation of Cu2+ ions in an aqueous solution. The Cu2+-imprinted polymer/montmorillonite (IIP/Mt) and non-imprinted polymer/montmorillonite (NIP/Mt) nanocomposites were prepared by a radical photopolymerization process in visible light. The ion imprinting step was indeed important as the recognition of copper ions by IIP/Mt was significantly superior to that of NIP/Mt, i.e., the reference nanocomposite synthesized in the same way but in the absence of Cu2+ ions. The adsorption process as batch study was investigated under the experimental condition affecting same parameters such as contact time, concentration of metal ions, and pH. The adsorption capacity of Cu2+ ions is maximized at pH 5. Removal of Cu2+ ion achieved equilibrium within 15 min; the results obtained were found to be fitted by the pseudo-second-order kinetics model. The equilibrium process was well described by the Langmuir isothermal model and the maximum adsorption capacity was found to be 23.6 mg/g. This is the first report on the design of imprinted polymer nanocomposites using Type II radical initiators under visible light in the presence of clay intercalated with hydrogen donor diazonium. The method is original, simple and efficient; it opens up new horizons in the general domain of clay/polymer nanocomposites.
Development of Bio-Based Films and 3D Objects from Apple Pomace
Authors: Gustafsson Jesper , Landberg Mikael , Bátori Veronika , Åkesson Dan , Taherzadeh Mohammad J. , Zamani Akram
Published: February 2019

Extensive quantities of apple pomace are generated annually but its disposal is still challenging. This study addresses this issue by introducing a new, environmentally-friendly approach for the production of sustainable biomaterials from apple pomace, containing 55.47% free sugars and a water insoluble fraction, containing 29.42 ± 0.44% hemicelluloses, 38.99 ± 0.42% cellulose, and 22.94 ± 0.12% lignin. Solution casting and compression molding were applied to form bio-based films and 3D objects (i.e., fiberboards), respectively. Using glycerol as plasticizer resulted in highly compact films with high tensile strength and low elongation (16.49 ± 2.54 MPa and 10.78 ± 3.19%, respectively). In contrast, naturally occurring sugars in the apple pomace showed stronger plasticizing effect in the films and resulted in a fluffier and connected structure with significantly higher elongation (37.39 ± 10.38% and 55.41 ± 5.38%, respectively). Benefiting from the self-binding capacity of polysaccharides, fiberboards were prepared by compression molding at 100 °C using glycerol or naturally occurring sugars, such as plasticizer. The obtained fiberboards exhibited tensile strength of 3.02–5.79 MPa and elongation of 0.93%–1.56%. Possible applications for apple pomace biomaterials are edible/disposable tableware or food packaging.
Drought and Human Impacts on Land Use and Land Cover Change in a Vietnamese Coastal Area
Authors: Tran Hoa Thi , Campbell James B. , Wynne Randolph H. , Shao Yang , Phan Son Viet
Published: February 2019

Drought is a dry-weather event characterized by a deficit of water resources in a period of year due to less rainfall than normal or overexploitation. This insidious hazard tends to occur frequently and more intensively in sub-humid regions resulting in changes in the landscape, transitions in agricultural practices and other environmental-social issues. The study area is in the sub-humid region of the northern coastal zone of Binh Thuan province, Vietnam—Tuy Phong district. This area is indicated as a subject of prolonged droughts during 6-month dry seasons, which have occurred more frequently in recent years. Associated with economic transitions in agricultural practicing, urbanization, and industrialization, prolonged droughts have resulted in rapid changes in land use and land cover (LULC) in Tuy Phong, especially in three coastal communes: Binh Thanh, Lien Huong, and Phuoc The. A bi-temporal analysis using high-resolution data, the 2011 WorldView2 and the 2016 GeoEye1, was examined to assess LULC changes from observed severe droughts in those three communes. Results showed a dramatic reduction in the extent of hydrological systems (about 20%), and significant increases of tree canopies in urban areas and near the coastal areas (approximately 76.8%). Paddy fields declined by 51% in 2016; such areas transitioned to inactive status or were alternated for growing drought-tolerant plants. Shrimp farming experienced a recognizable decrease by approximately 44%. The 2014 map and field observations during summer 2016 provide references for object-based classification and validation. Overall agreement of results is about 85%.
Classification of Crops, Pastures, and Tree Plantations along the Season with Multi-Sensor Image Time Series in a Subtropical Agricultural Region
Authors: Lira Melo de Oliveira Santos Cecília , Augusto Camargo Lamparelli Rubens , Kelly Dantas Araújo Figueiredo Gleyce , Dupuy Stéphane , Boury Julie , Luciano Ana Cláudia dos Santos , Torres Ricardo da Silva , le Maire Guerric
Published: February 2019

Timely and efficient land-cover mapping is of high interest, especially in agricultural landscapes. Classification based on satellite images over the season, while important for cropland monitoring, remains challenging in subtropical agricultural areas due to the high diversity of management systems and seasonal cloud cover variations. This work presents supervised object-based classifications over the year at 2-month time-steps in a heterogeneous region of 12,000 km2 in the Sao Paulo region of Brazil. Different methods and remote-sensing datasets were tested with the random forest algorithm, including optical and radar data, time series of images, and cloud gap-filling methods. The final selected method demonstrated an overall accuracy of approximately 0.84, which was stable throughout the year, at the more detailed level of classification; confusion mainly occurred among annual crop classes and soil classes. We showed in this study that the use of time series was useful in this context, mainly by including a small number of highly discriminant images. Such important images were eventually distant in time from the prediction date, and they corresponded to a high-quality image with low cloud cover. Consequently, the final classification accuracy was not sensitive to the cloud gap-filling method, and simple median gap-filling or linear interpolations with time were sufficient. Sentinel-1 images did not improve the classification results in this context. For within-season dynamic classes, such as annual crops, which were more difficult to classify, field measurement efforts should be densified and planned during the most discriminant window, which may not occur during the crop vegetation peak.
Soil Moisture Variability in India: Relationship of Land Surface–Atmosphere Fields Using Maximum Covariance Analysis
Authors: Pangaluru Kishore , Velicogna Isabella , A Geruo , Mohajerani Yara , Ciracì Enrico , Charakola Sravani , Basha Ghouse , Rao S. Vijaya Bhaskara
Published: February 2019

This study investigates the spatial and temporal variability of the soil moisture in India using Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) gridded datasets from June 2002 to April 2017. Significant relationships between soil moisture and different land surface–atmosphere fields (Precipitation, surface air temperature, total cloud cover, and total water storage) were studied, using maximum covariance analysis (MCA) to extract dominant interactions that maximize the covariance between two fields. The first leading mode of MCA explained 56%, 87%, 81%, and 79% of the squared covariance function (SCF) between soil moisture with precipitation (PR), surface air temperature (TEM), total cloud count (TCC), and total water storage (TWS), respectively, with correlation coefficients of 0.65, −0.72, 0.71, and 0.62. Furthermore, the covariance analysis of total water storage showed contrasting patterns with soil moisture, especially over northwest, northeast, and west coast regions. In addition, the spatial distribution of seasonal and annual trends of soil moisture in India was estimated using a robust regression technique for the very first time. For most regions in India, significant positive trends were noticed in all seasons. Meanwhile, a small negative trend was observed over southern India. The monthly mean value of AMSR soil moisture trend revealed a significant positive trend, at about 0.0158 cm3/cm3 per decade during the period ranging from 2002 to 2017.
Digital Aerial Photogrammetry for Uneven-Aged Forest Management: Assessing the Potential to Reconstruct Canopy Structure and Estimate Living Biomass
Authors: Jayathunga Sadeepa , Owari Toshiaki , Tsuyuki Satoshi
Published: February 2019

Scientifically robust yet economical and efficient methods are required to gather information about larger areas of uneven-aged forest resources, particularly at the landscape level, to reduce deforestation and forest degradation and to support the sustainable management of forest resources. In this study, we examined the potential of digital aerial photogrammetry (DAP) for assessing uneven-aged forest resources. Specifically, we tested the performance of biomass estimation by varying the conditions of several factors, e.g., image downscaling, vegetation metric extraction (point cloud- and canopy height model (CHM)-derived), modeling method ((simple linear regression (SLR), multiple linear regression (MLR), and random forest (RF)), and season (leaf-on and leaf-off). We built dense point clouds and CHMs using high-resolution aerial imagery collected in leaf-on and leaf-off conditions of an uneven-aged mixed conifer–broadleaf forest. DAP-derived vegetation metrics were then used to predict the dominant height and living biomass (total, conifer, and broadleaf) at the plot level. Our results demonstrated that image downscaling had a negative impact on the accuracy of the dominant height and biomass estimation in leaf-on conditions. In comparison to CHM-derived vegetation metrics, point cloud-derived metrics performed better in dominant height and biomass (total and conifer) estimations. Although the SLR (%RMSE = 21.1) and MLR (%RMSE = 18.1) modeling methods produced acceptable results for total biomass estimations, RF modeling significantly improved the plot-level total biomass estimation accuracy (%RMSE of 12.0 for leaf-on data). Overall, leaf-on DAP performed better in total biomass estimation compared to leaf-off DAP (%RMSE of 15.0 using RF modeling). Nevertheless, conifer biomass estimation accuracy improved when leaf-off data were used (from a %RMSE of 32.1 leaf-on to 23.8 leaf-off using RF modeling). Leaf-off DAP had a negative impact on the broadleaf biomass estimation (%RMSE > 35% for SLR, MLR, and RF modeling). Our results demonstrated that the performance of forest biomass estimation for uneven-aged forests varied with statistical representations as well as data sources. Thus, it would be appropriate to explore different statistical approaches (e.g., parametric and nonparametric) and data sources (e.g., different image resolutions, vegetation metrics, and leaf-on and leaf-off data) to inform the interpretation of remotely sensed data for biomass estimation for uneven-aged forest resources.
Improving the Performance of Galileo Uncombined Precise Point Positioning Ambiguity Resolution Using Triple-Frequency Observations
Authors: Liu Gen , Zhang Xiaohong , Li Pan
Published: February 2019

Compared with the traditional ionospheric-free linear combination precise point positioning (PPP) model, the un-differenced and uncombined (UDUC) PPP model using original observations can keep all the information of the observations and be easily extended to any number of frequencies. However, the current studies about the multi-frequency UDUC-PPP ambiguity resolution (AR) were mainly based on the triple-frequency BeiDou navigation satellite system (BDS) observations or simulated data. Limited by many factors, for example the accuracy of BDS precise orbit and clock products, the advantages of triple-frequency signals to UDUC-PPP AR were not fully exploited. As Galileo constellations have been upgraded by increasing the number of 19 useable satellites, it makes using Galileo satellites to further study the triple-frequency UDUC-PPP ambiguity resolution (AR) possible. In this contribution, we proposed the method of multi-frequency step-by-step ambiguity resolution based on the UDUC-PPP model and gave the reason why the performance of PPP AR can be improved using triple-frequency observations. We used triple-frequency Galileo observations on day of year (DOY) 201, 2018 provided by 166 Multi-GNSS Experiment (MGEX) stations to estimate original uncalibrated phase delays (UPD) on each frequency and to conduct both dual- and triple-frequency UDUC-PPP AR. The performance of UDUC-PPP AR based on post-processing mode was assessed in terms of the time-to-first-fix (TTFF) as well as positioning accuracy with 2-h observations. It was found that triple-frequency observations were helpful to reduce TTFF and improve the positioning accuracy. The current statistic results showed that triple-frequency PPP-AR reduced the averaged TTFF by 19.6% and also improved the positioning accuracy by 40.9%, 31.2% and 23.6% in the east, north and up directions respectively, compared with dual-frequency PPP-AR. With an increasing number of Galileo satellites, it is expected that the robustness and accuracy of the triple-frequency UCUD-PPP AR can be improved further.
Real-Time Monitoring of Jet Trajectory during Jetting Based on Near-Field Computer Vision
Authors: Zhu Jinsong , Li Wei , Lin Da , Zhao Ge
Published: February 2019

A novel method of near-field computer vision (NFCV) was developed to monitor the jet trajectory during the jetting process, which was used to precisely predict the falling point position of the jet trajectory. By means of a high-resolution webcam, the NFCV sensor device collected near-field images of the jet trajectory. Preprocessing of collected images was carried out, which included squint image correction, noise elimination, and jet trajectory extraction. The features of the jet trajectory in the processed image were extracted, including: start-point slope (SPS), end-point slope (EPS), and overall trajectory slope (OTS) based on the proposed mean position method. A multiple regression jet trajectory range prediction model was established based on these trajectory characteristics and the reliability of the model was verified. The results show that the accuracy of the prediction model is not less than 94% and the processing time is less than 0.88 s, which satisfy the requirements of real-time online jet trajectory monitoring.
Improvement of 3D Power Line Extraction from Multiple Low-Cost UAV Imagery Using Wavelet Analysis
Authors: Fryskowska Anna
Published: February 2019

Three-dimensional (3D) mapping of power lines is very important for power line inspection. Many remotely-sensed data products like light detection and ranging (LiDAR) have been already studied for power line surveys. More and more data are being obtained via photogrammetric measurements. This increases the need for the implementation of advanced processing techniques. In recent years, there have been several developments in visualisation techniques using UAV (unmanned aerial vehicle) platform photography. The most modern of such imaging systems have the ability to generate dense point clouds. However, image-based point cloud accuracy is very often various (unstable) and dependent on the radiometric quality of images and the efficiency of image processing algorithms. The main factor influencing the point cloud quality is noise. Such problems usually arise with data obtained via low-cost UAV platforms. Therefore, generated point clouds representing power lines are usually incomplete and noisy. To obtain a complete and accurate 3D model of power lines and towers, it is necessary to develop improved data processing algorithms. The experiment tested the algorithms on power lines with different voltages. This paper presents the wavelet-based method of processing data acquired with a low-cost UAV camera. The proposed, original method involves the application of algorithms for coarse filtration and precise filtering. In addition, a new way of calculating the recommended flight height was proposed. At the end, the accuracy assessment of this two-stage filtration process was examined. For this, point quality indices were proposed. The experimental results show that the proposed algorithm improves the quality of low-cost point clouds. The proposed methods improve the accuracy of determining the parameters of the lines by more than twice. About 10% of noise is reduced by using the wavelet-based approach.
Long-Term Ground Settlements over Mined-Out Region Induced by Railway Construction and Operation
Authors: Jiang Shuo , Wang Yimin
Published: February 2019

With the rapid development of railway construction and the massive exploitation of mineral resources, many railway projects have had to cross mining areas and their caverns. However, the settlement of the ground surface may cause severe damage to human-built structures and lead to the loss of human lives. The research on ground deformation monitoring over caverns is undoubtedly important and has a guiding role in railway design. Settlement observation points were set up around the mine, establishing a ground subsidence monitoring level network that has been in operation for 11 years. The ground settlement and lateral displacement along the designed railway were studied. A finite element model was established to predict the long-term ground settlements over the mined-out region induced by designed railway embankment construction and train operation. The results show that the predicted ground settlement induced by railway embankment construction is smaller than the ground settlement induced by the mined-out cavity. One train pass-by has an insignificant impact on the safety of train operation. However, when the number of train pass-bys increases to 10,000,000 times and 20,000,000 times, the cumulative deformations of the ground at different depths are quite large, which may affect the safety of the railway operation. Thus, it is necessary to deal with settlement issues when designing railway construction.
ESD for Public Administration: An Essential Challenge for Inventing the Future of Our Society
Authors: Păvăloaia Vasile-Daniel , Georgescu Mircea Radu , Popescul Daniela , Radu Laura-Diana
Published: February 2019

The role of local and central public administrations in promoting sustainable development and building up a better future for society is essential. In order to fulfill this mission, employees in public administration sector must engage in long life learning processes, for the purpose of developing skills such as: anticipation, interdisciplinarity, diversity of perspectives, working with incomplete or complex information, participation in sustainable development processes, cooperation, individual decision-making capacities, empathy, solidarity, and self-motivation. The Education for Sustainable Development as a component of lifelong learning is, in this light, of utmost importance. In this spirit, this paper investigates what is the Romanian public sector employees’ perception of long life learning as an essential premise of Education for Sustainable Development, by analysing on the one hand the degree of digital maturity of public institutions in Romania, and on the other hand the interest of employees in such institutions to engage in Education for Sustainable Development function of the following disjunct behavioural/emotional states: Disappointment, Conflicts, Satisfaction/Contentment, Doubt, Exhaustion, Attachment.
Research on Two-Way Logistics Operation with Uncertain Recycling Quality in Government Multi-Policy Environment
Authors: Tan Yue , Guo Chunxiang
Published: February 2019

With the emphasis on environmental protection issues, countries have introduced a number of circular economy-related policies aimed at guiding enterprises to green development and green innovation. At the same time, they are encouraged to strengthen the combination of forward logistics and reverse logistics, providing an effective way to improve resource shortages and reduce environmental pollution. However, the quality of recycled products in reverse logistics is often uncertain, which not only increases the risk of production decisions of remanufacturers, but also affects the sales of new products in the forward logistics to a certain extent. Based on the uncertainty of recycling quality of waste products and the controllability of remanufacturing technology level, this paper studies the impact of various regulatory environments on the operation of a two-way logistics system. We solve the decision model of the system through game theory. The results show that the government’s policy can improve product recycling quality and remanufacturing technology. However, recycling rewards and punishments, remanufacturing technology subsidies, and recycling payment factors need to be within a certain range to ensure the effectiveness of the trading market. When the recycling regulation has been implemented, it is beneficial for manufacturers to choose to improve their remanufacturing technology level. This means that the combined effect of multiple policies is more conducive to the operation of a two-way logistics system.
Big Data: From Forecasting to Mesoscopic Understanding. Meta-Profiling as Complex Systems
Authors: Minati Gianfranco
Published: February 2019

We consider Big Data as a phenomenon with acquired properties, similar to collective behaviours, that establishes virtual collective beings. We consider the occurrence of ongoing non-equivalent multiple properties in the conceptual framework of structural dynamics given by sequences of structures and not only by different values assumed by the same structure. We consider the difference between modelling and profiling in a constructivist way, as De Finetti intended probability to exist, depending on the configuration taken into consideration. The past has little or no influence, while events and their configurations are not memorised. Any configuration of events is new, and the probabilistic values to be considered are reset. As for collective behaviours, we introduce methodological and conceptual proposals using mesoscopic variables and their property profiles and meta-profile Big Data and non-computable profiles which were inspired by the use of natural computing to deal with cyber-ecosystems. The focus is on ongoing profiles, in which the arising properties trace trajectories, rather than assuming that we can foresee them based on the past.
Thiol-free chemoenzymatic synthesis of β-ketosulfides
Authors: Heredia Adrián A , López-Vidal Martín G , Kurina-Sanz Marcela , Bisogno Fabricio R , Peñéñory Alicia B
Published: February 2019

A preparation of β-ketosulfides avoiding the use of thiols is described. The combination of a multicomponent reaction and a lipase-catalysed hydrolysis has been developed in order to obtain high chemical diversity employing a single sulfur donor. This methodology for the selective synthesis of a set of β-ketosulfides is performed under mild conditions and can be set up in one-pot two-step and on a gram-scale.
THE ANALYSIS OF THE INFLUENCE OF EXTERNAL ENVIRONMENT FACTORS ON THE EFFICIENCY OF MAINTENANCE CONTRACTORS ACTIVITIES
Authors: Vilutiene Tatjana , Malinauskas Pranas
Published: February 2019

The article presents the analysis of factors influencing the efficiency of dwelling maintenance contractors activities. The criteria characterizing the activities of maintenance contractors were determined performing the financial analysis of the company. The influence of external environment factors on maintenance contractors activities indicators was determined by calculating their correlation coefficients. In order to verify the calculation results the specialists from maintenance companies and heads of dwelling owners associations were interrogated. They showed the main maintenance problems and factors which influence the efficiency of maintenance process.
ESTIMATION OF EXTERNAL WALLS DECISIONS OF MULTISTOREY RESIDENTIAL BUILDINGS APPLYING METHODS OF MULTICRITERIA ANALYSIS
Authors: Zavadskas Edmundas Kazimieras , Ustinovičius Leonas , Turskis Zenonas , Ambrasas Gintautas , Kutut Vladislavas
Published: February 2019

This paper analyses the most widespread designs of external walls of the multi‐storey residential buildings now in use. Such 49 alternative designs of external walls of multi‐storey residential buildings are analyzed using multicriteria analysis program under uncertainty. Few ways of the decision are applied for the decision of the problem: the method of distance to an ideal point, Baye's rule and Wald's rule. To project and understand effective construction of a building, it is necessary to execute exhaustive analysis of all decisions (planimetric, prolongation of term and quality of buildings operation, improvement of architectural decisions, etc.). The level of a design of external walls efficiency of multi‐storey residential buildings depends on very many factors, including: cost of the construction work, used materials and building mechanisms, aesthetics, properties of service, thermal insulation properties, durability, etc. The offered decision of the choice of the effective decision problem using the system of the criteria having different dimensions takes into account the rational estimation of economic, climatic, social conditions and traditions and also allows better to satisfy architectural, functional, service, comfort and other requirements of the client. It also allows to reduce design, building and operational expenses. The choice of a variant mainly depends on needs and existing financial ability of the customer. The offered system of the effective decision choice using the principles of the multi‐criteria analysis is described in the presented paper. There is an opportunity on the basis of the offered system to compare alternative design decisions of external walls of multi‐storey residential buildings and the choice of the most effective variants.
KNOWLEDGE MANAGEMENT AND “BRITA IN PUBS” PROJECT
Authors: Kaklauskas Artūras , Kanapeckiene Loreta
Published: February 2019

Driven by the rapid shift to information‐based products and business strategies the discipline of knowledge management is emerging as the inevitable next step toward productivity and competitiveness in modern business — and a major market opportunity for vendors of a variety of information-related computer products. The proper analysis of the terminology of technologies that contribute to knowledge management solutions is the subject of this paper. This paper provides a high‐level overview of a number of key terms and concepts, describes the framework, provides examples of how to use it and explores a variety of potential application areas. The main comparative analysis of the definitions which were received from different terminology systems has been completed. It provides a framework for characterizing various tools (methods, practices and technologies) available to multiple criteria decision‐making in the dwelling‐housing procedure. In this paper we present a short description of “BRITA in PuBs” project.
STRUCTURAL‐TECHNOLOGICAL FACTORS OF EFFICIENCY OF FLOORS WITH PERMANENT REINFORCED CONCRETE FORMWORK
Authors: Marčiukaitis Gediminas , Bistrickaite Reda
Published: February 2019

Problems associated with the development of reinforced concrete floors, the main element of a building, are considered in this article. Structural and technological factors effecting the advantages of floors with permanent formwork being the modern type of such structures are investigated. Rational diagrams, ways of manufacture and erection of these structures are presented. Essential peculiarities for design and analyses of such structures based on the investigations performed by the author and other investigators are indicated. This shall be taken into account for obtaining not only economical, but a reliable and rigid structure as well. Economical comparison of various types of floors is presented.
A COMPARATIVE ANALYSIS OF ENGLISH AND LITHUANIAN TECHNICAL TERMS
Authors: Marina Valerija
Published: February 2019

The paper presents a comparative analysis of English and Lithuanian metaphorical terms based on the names of the parts of human body, plants, animals, materials, clothes, utensils, etc. The analysis is aimed at identifying their common and differing features as well as spotting the specific patterns of English terms presenting difficulties for speakers of Lithuanian in their comprehension, translation and usage. It has been found that metaphorical terms are used by both languages, however, they are more common in English. The differences lie not only in the number of the respective terms but in the semantic structure as well. English terms of the models considered often do not allow for literal translation. The difficulties of their comprehension and translation may be overcome by applying the theory of linguistic relativity. Different approaches of the English and Lithuanian languages to classifying the objects of reality are also considered within the framework of linguistic relativity and some case studies are presented.
PROJEKTMANAGEMENT AM KONSTRUKTIONSBEISPIEL VANDALISMUSGESCHÜTZTER LEUCHTENSYSTEME
Authors: Pracht Friedhelm
Published: February 2019

Unfortunately public buildings and municipal transportation facilities are vandalised. We have the same problem with luminaires in the mentioned application areas. Luminaires are not only exposed to weather but also to increasing vandalism. For the purpose of the product responsibility and the subsequent recycling, namely to work with as few different non‐polluting and easy to depollute materials as possible, this issue is discussed with regard to the realisation of a new vandal‐resistant liminaire system with high safety classification IP 65 and optionally in protection class I and II (double insulated).