bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and Fluorescence Spectroscopic Studies of Novel 9-phenylacridino-18-crown-6 Ether Type Sensor Molecules
Authors: Németh Tamás , Tóth Tünde , Balogh György Tibor , Huszthy Péter
Published: September 2017

The synthesis of two new 9-phenylacridino-18-crown-6 ether type sensor molecules [1 and (R,R)-2] was accomplished. The cation recognition ability of the achiral sensor molecule 1 towards various ions was studied in acetonitrile by UV/Vis and fluorescence spectroscopies. Our studies revealed the binding of Ag+, Cd2+, Ni2+, Pb2+, Zn2+ and NH4+ ions by the latter molecule. Selectivity of the chiral dimethyl-substituted analogue (R,R)-2 was studied toward the enantiomers of the hydrogen perchlorate salts of 1-phenylethylamine, 1-(1-naphthyl)ethylamine, phenylglycine methyl ester and phenylalanine methyl ester using fluorescence spectroscopy.
Why did Hume not Become an Atheist?: The Influence of Butler on Hume's Dialogues
Authors: Yajima Naoki
Published: September 2017

This article aims to illuminate the background and intention of Hume's Dialogues. It argues that ‘Cleanthes’ is significantly modeled after Butler's thought by showing the connection between Part IX of the Dialogues and Butler's early correspondence with Clarke regarding the concepts of probability and conceivability. This clarifies Philo's ‘reversal’ in Part XII. Butler's theory of probability provides a clue to Hume's moderate skepticism which stops short of endorsing atheism. Hume presents a philosophical narrative in which readers are invited to entertain philosophical thinking on natural theology as a preliminary to identifying ‘true’ religion rather than affirming atheism.
Interlayers Applied to CVD Diamond Deposition on Steel Substrate: A Review
Authors: Damm Djoille , Contin André , Barbieri Fernando , Trava-Airoldi Vladimir , Barquete Danilo , Corat Evaldo
Published: September 2017

Academics and industry have sought after combining the exceptional properties of diamonds with the toughness of steel. Since the early 1990s several partial solutions have been found but chemical vapor deposition (CVD) diamond deposition on steel substrate continues to be a persistent problem. The main drawbacks are the high carbon diffusion from gas phase into substrate, the transition metals on the material surface that catalyze sp2 bond formation, instead of sp3 bonds, and the high thermal expansion coefficient (TEC) mismatch between diamond and steels. An intermediate layer has been found necessary to increase diamond adhesion. Literature has proposed many efficient intermediate layers as a diffusion barrier for both, carbon and iron, but most intermediate layers shown have not solved TEC mismatch. In this review, we briefly discuss the solutions that exclusively work as diffusion barrier and discuss in a broader way the ones that also solve, or may potentially solve, the TEC mismatch problem. We examine some multilayers, the iron borides, the chromium carbides, and vanadium carbides. We go through the most relevant results of the last two and a half decades, including recent advances in our group. Vanadium carbide looks promising since it has shown excellent diffusion barrier properties, its TEC is intermediary between diamond and steel and, it has been thickened to manage thermal stress relief. We also review a new deposition technique to set up intermediate layers: laser cladding. It is promising because of its versatility in mixing different materials and fusing and/or sintering them on a steel surface. We conclude by remarking on new perspectives.
Zircon-Based Ceramic Coatings Formed by a New Multi-Chamber Gas-Dynamic Accelerator
Authors: Kovaleva Marina , Prozorova Mayya , Arseenko Maria , Tyurin Yuri , Kolisnichenko Oleg , Yapryntsev Maxim , Novikov Vseslav , Vagina Olga , Sirota Viacheslav
Published: September 2017

In this work, dense zircon-based ceramic coatings were obtained from inexpensive zircon powder on a steel substrate by using a new multi-chamber gas-dynamic accelerator. The microstructure and phase composition of the coating were characterized by scanning electron microscopy, optical microscopy, and X-ray diffraction. The mechanical properties of the coatings were evaluated using microindentation, wear tests and bonding strength tests. The results showed that the obtained zircon-based ceramic coatings were continuous without cracks and bonded well with substrate without a sublayer. The zircon-based ceramic coatings consisted of c-ZrO2 (major phase), m-ZrO2 and SiO2. The zircon-based ceramic coatings had a porosity of 0.1%, hardness of 526 ± 65 HV0.2, and a fracture toughness of 2.5 ± 0.6 (МPа∙m1/2). The coatings showed the low specific wear rate and average erosion rate. The failure mode occurring in the tested coatings was cohesive.
Modeling and Analysis of the Common Mode Voltage in a Cascaded H-Bridge Electronic Power Transformer
Authors: Yang Yun , Mao Chengxiong , Wang Dan , Tian Jie , Yang Ming
Published: September 2017

Electronic power transformers (EPTs) have been identified as emerging intelligent electronic devices in the future smart grid, e.g., the Energy Internet, especially in the application of renewable energy conversion and management. Considering that the EPT is directly connected to the medium-voltage grid, e.g., a10 kV distribution system, and its cascaded H-bridges structure, the common mode voltage (CMV) issue will be more complex and severe. The CMV will threaten the insulation of the entire EPT device and even produce common mode current. This paper investigates the generated mechanism and characteristics of the CMV in a cascaded H-bridge EPT (CHB-EPT) under both balanced and fault grid conditions. First, the CHB-EPT system is introduced. Then, a three-phase simplified circuit model of the high-voltage side of the EPT system is presented. Combined with a unipolar modulation strategy and carrier phase shifting technology by rigorous mathematical analysis and derivation, the EPT internal CMV and its characteristics are obtained. Moreover, the influence of the sinusoidal pulse width modulation dead time is considered and discussed based on analytical calculation. Finally, the simulation results are provided to verify the validity of the aforementioned model and the analysis results. The proposed theoretical analysis method is also suitable for other similar cascaded converters and can provide a useful theoretical guide for structural design and power density optimization.
Work-Related Noise Exposure in a Cohort of Patients with Chronic Tinnitus: Analysis of Demographic and Audiological Characteristics
Authors: Ralli Massimo , Balla Maria Paola , Greco Antonio , Altissimi Giancarlo , Ricci Pasquale , Turchetta Rosaria , De Virgilio Armando , De Vincentiis Marco , Ricci Serafino , Cianfrone Giancarlo
Published: September 2017

Work-related noise exposure is one of the major factors contributing to the development of adult-onset hearing loss and tinnitus. The aim of this study was to analyze, in patients with chronic tinnitus and long-term occupational noise exposure, (A) characteristics of hearing loss, tinnitus, comorbidities, demographic characteristics and a history of work-related noise exposure and (B) differences among individuals employed in occupations with high and low risk of developing work-related noise-induced hearing loss (NIHL). One hundred thirty six patients with chronic tinnitus and at least a 10 year-long working history were divided into two groups based on the risk of their profession to induce NIHL. Individuals employed in jobs at high risk for NIHL were mostly males and exhibited a poorer hearing threshold, more evident in the left ear. Tinnitus was mostly bilateral; the next largest presentation was left-sided; patients described their tinnitus as buzzing or high-pitched. Correlation between age, length of tinnitus and worse hearing was found. Patients with a higher degree of hearing impairment were mostly males and were more likely to have a family history of hearing loss and at least one cardiovascular comorbidity. Our study shows some differences in individuals with tinnitus and a history of a profession associated with increased exposure to NIHL compared to those without such a history.
GeoSpark SQL: An Effective Framework Enabling Spatial Queries on Spark
Authors: Huang Zhou , Chen Yiran , Wan Lin , Peng Xia
Published: September 2017

In the era of big data, Internet-based geospatial information services such as various LBS apps are deployed everywhere, followed by an increasing number of queries against the massive spatial data. As a result, the traditional relational spatial database (e.g., PostgreSQL with PostGIS and Oracle Spatial) cannot adapt well to the needs of large-scale spatial query processing. Spark is an emerging outstanding distributed computing framework in the Hadoop ecosystem. This paper aims to address the increasingly large-scale spatial query-processing requirement in the era of big data, and proposes an effective framework GeoSpark SQL, which enables spatial queries on Spark. On the one hand, GeoSpark SQL provides a convenient SQL interface; on the other hand, GeoSpark SQL achieves both efficient storage management and high-performance parallel computing through integrating Hive and Spark. In this study, the following key issues are discussed and addressed: (1) storage management methods under the GeoSpark SQL framework, (2) the spatial operator implementation approach in the Spark environment, and (3) spatial query optimization methods under Spark. Experimental evaluation is also performed and the results show that GeoSpark SQL is able to achieve real-time query processing. It should be noted that Spark is not a panacea. It is observed that the traditional spatial database PostGIS/PostgreSQL performs better than GeoSpark SQL in some query scenarios, especially for the spatial queries with high selectivity, such as the point query and the window query. In general, GeoSpark SQL performs better when dealing with compute-intensive spatial queries such as the kNN query and the spatial join query.
Monitoring and Modeling of Spatiotemporal Urban Expansion and Land-Use/Land-Cover Change Using Integrated Markov Chain Cellular Automata Model
Authors: Rimal Bhagawat , Zhang Lifu , Keshtkar Hamidreza , Wang Nan , Lin Yi
Published: September 2017

Spatial–temporal analysis of land-use/land-cover (LULC) change as well as the monitoring and modeling of urban expansion are essential for the planning and management of urban environments. Such environments reflect the economic conditions and quality of life of the individual country. Urbanization is generally influenced by national laws, plans and policies and by power, politics and poor governance in many less-developed countries. Remote sensing tools play a vital role in monitoring LULC change and measuring the rate of urbanization at both the local and global levels. The current study evaluated the LULC changes and urban expansion of Jhapa district of Nepal. The spatial–temporal dynamics of LULC were identified using six time-series atmospherically-corrected surface reflectance Landsat images from 1989 to 2016. A hybrid cellular automata Markov chain (CA–Markov) model was used to simulate future urbanization by 2026 and 2036. The analysis shows that the urban area has increased markedly and is expected to continue to grow rapidly in the future, whereas the area for agriculture has decreased. Meanwhile, forest and shrub areas have remained almost constant. Seasonal rainfall and flooding routinely cause predictable transformation of sand, water bodies and cultivated land from one type to another. The results suggest that the use of Landsat time-series archive images and the CA–Markov model are the best options for long-term spatiotemporal analysis and achieving an acceptable level of prediction accuracy. Furthermore, understanding the relationship between the spatiotemporal dynamics of urbanization and LULC change and simulating future landscape change is essential, as they are closely interlinked. These scientific findings of past, present and future land-cover scenarios of the study area will assist planners/decision-makers to formulate sustainable urban development and environmental protection plans and will remain a scientific asset for future generations.
Dystrophic Cardiomyopathy: Complex Pathobiological Processes to Generate Clinical Phenotype
Authors: Tsuda Takeshi , Fitzgerald Kristi
Published: September 2017

Duchenne muscular dystrophy (DMD), Becker muscular dystrophy (BMD), and X-linked dilated cardiomyopathy (XL-DCM) consist of a unique clinical entity, the dystrophinopathies, which are due to variable mutations in the dystrophin gene. Dilated cardiomyopathy (DCM) is a common complication of dystrophinopathies, but the onset, progression, and severity of heart disease differ among these subgroups. Extensive molecular genetic studies have been conducted to assess genotype-phenotype correlation in DMD, BMD, and XL-DCM to understand the underlying mechanisms of these diseases, but the results are not always conclusive, suggesting the involvement of complex multi-layers of pathological processes that generate the final clinical phenotype. Dystrophin protein is a part of dystrophin-glycoprotein complex (DGC) that is localized in skeletal muscles, myocardium, smooth muscles, and neuronal tissues. Diversity of cardiac phenotype in dystrophinopathies suggests multiple layers of pathogenetic mechanisms in forming dystrophic cardiomyopathy. In this review article, we review the complex molecular interactions involving the pathogenesis of dystrophic cardiomyopathy, including primary gene mutations and loss of structural integrity, secondary cellular responses, and certain epigenetic and other factors that modulate gene expressions. Involvement of epigenetic gene regulation appears to lead to specific cardiac phenotypes in dystrophic hearts.
Research on High Layer Thickness Fabricated of 316L by Selective Laser Melting
Authors: Wang Shuo , Liu Yude , Shi Wentian , Qi Bin , Yang Jin , Zhang Feifei , Han Dong , Ma Yingyi
Published: September 2017

Selective laser melting (SLM) is a potential additive manufacturing (AM) technology. However, the application of SLM was confined due to low efficiency. To improve efficiency, SLM fabrication with a high layer thickness and fine powder was systematically researched, and the void areas and hollow powders can be reduced by using fine powder. Single-track experiments were used to narrow down process parameter windows. Multi-layer fabrication relative density can be reached 99.99% at the exposure time-point distance-hatch space of 120 μs-40 μm-240 μm. Also, the building rate can be up to 12 mm3/s, which is about 3–10 times higher than the previous studies. Three typical defects were found by studying deeply, including the un-melted defect between the molten pools, the micro-pore defect within the molten pool, and the irregular distribution of the splashing phenomenon. Moreover, the microstructure is mostly equiaxed crystals and a small amount of columnar crystals. The averages of ultimate tensile strength, yield strength, and elongation are 625 MPa, 525 MPa, and 39.9%, respectively. As exposure time increased from 80 μs to 200 μs, the grain size is gradually grown up from 0.98 μm to 2.23 μm, the grain aspect ratio is close to 1, and the tensile properties are shown as a downward trend. The tensile properties of high layer thickness fabricated are not significantly different than those with a coarse-powder layer thickness of low in previous research.
Self-Assembled Gold Nano-Ripple Formation by Gas Cluster Ion Beam Bombardment
Authors: Tilakaratne Buddhi , Chen Quark , Chu Wei-Kan
Published: September 2017

In this study, we used a 30 keV argon cluster ion beam bombardment to investigate the dynamic processes during nano-ripple formation on gold surfaces. Atomic force microscope analysis shows that the gold surface has maximum roughness at an incident angle of 60° from the surface normal; moreover, at this angle, and for an applied fluence of 3 × 1016 clusters/cm2, the aspect ratio of the nano-ripple pattern is in the range of ~50%. Rutherford backscattering spectrometry analysis reveals a formation of a surface gradient due to prolonged gas cluster ion bombardment, although the surface roughness remains consistent throughout the bombarded surface area. As a result, significant mass redistribution is triggered by gas cluster ion beam bombardment at room temperature. Where mass redistribution is responsible for nano-ripple formation, the surface erosion process refines the formed nano-ripple structures.
Polymeric Nanocomposite Membranes for Next Generation Pervaporation Process: Strategies, Challenges and Future Prospects
Authors: Roy Sagar , Singha Nayan
Published: September 2017

Pervaporation (PV) has been considered as one of the most active and promising areas in membrane technologies in separating close boiling or azeotropic liquid mixtures, heat sensitive biomaterials, water or organics from its mixtures that are indispensable constituents for various important chemical and bio-separations. In the PV process, the membrane plays the most pivotal role and is of paramount importance in governing the overall efficiency. This article evaluates and collaborates the current research towards the development of next generation nanomaterials (NMs) and embedded polymeric membranes with regard to its synthesis, fabrication and application strategies, challenges and future prospects.
Rheology of Fly Ash Mixed Tailings Slurries and Applicability of Prediction Models
Authors: Lee Joon Kyu , Ko Junyoung , Kim Young Sang
Published: September 2017

Coal fly ash has potential applications in the management of reactive mine tailings. The shear stress versus shear rate curves obtained during viscometer tests are presented to describe the rheological behaviors of tailings slurries mixed with fly ash. The investigation was conducted on specimens prepared with different fly ash additions as well as prepared at variable conditions of temperature, mixing time, and CaCl2 solution. It was observed that the rheological properties of ash-tailings slurry mixtures are influenced by the hydration of fly ash as well as the particle packing and arrangement. Rheological properties of specimen mixtures were determined from the resulting flow curves using the existing rheological models. The performance of prediction models in calculating the rheological properties of the mixed specimens, as quantified by the root mean square error (RMSE), varied with the mixture constituents, temperature, and time. In general, the Papanastasion, Herschel-Bulkley, Sisko, and Robertson-Stiff models were found to be favorable for use with mixtures of fly ash and tailings slurries, compared to the Bingham, Modified Bingham, Casson, and De Kee models.
Anti-HIV Activities and Mechanism of 12-O-Tricosanoylphorbol-20-acetate, a Novel Phorbol Ester from Ostodes katharinae
Authors: Chen Huan , Zhang Rong , Luo Rong-Hua , Yang Liu-Meng , Wang Rui-Rui , Hao Xiao-Jiang , Zheng Yong-Tang
Published: September 2017

APOBEC3G is a member of the human cytidine deaminase family that restricts Vif-deficient viruses by being packaged with progeny virions and inducing the G to A mutation during the synthesis of HIV-1 viral DNA when the progeny virus infects new cells. HIV-1 Vif protein resists the activity of A3G by mediating A3G degradation. Phorbol esters are plant-derived organic compounds belonging to the tigliane family of diterpenes and could activate the PKC pathway. In this study, we identified an inhibitor 12-O-tricosanoylphorbol-20-acetate (hop-8), a novel ester of phorbol which was isolated from Ostodes katharinae of the family Euphorbiaceae, that inhibited the replication of wild-type HIV-1 and HIV-2 strains and drug-resistant strains broadly both in C8166 cells and PBMCs with low cytotoxicity and the EC50 values ranged from 0.106 μM to 7.987 μM. One of the main mechanisms of hop-8 is to stimulate A3G expressing in HIV-1 producing cells and upregulate the A3G level in progeny virions, which results in reducing the infectivity of the progeny virus. This novel mechanism of hop-8 inhibition of HIV replication might represents a promising approach for developing new therapeutics for HIV infection.
Effect of Vertical Shoot-Positioned, Scott-Henry, Geneva Double-Curtain, Arch-Cane, and Parral Training Systems on the Volatile Composition of Albariño Wines
Authors: Vilanova Mar , Genisheva Zlatina , Tubio Miguel , Álvarez Katia , Lissarrague Jose , Oliveira José
Published: September 2017

Viticultural practices influence both grape and wine quality. The influence of training systems on volatile composition was investigated for Albariño wine from Rías Baixas AOC in Northwest Spain. The odoriferous contribution of the compounds to the wine aroma was also studied. Volatile compounds belonging to ten groups (alcohols, C6-compounds, ethyl esters, acetates, terpenols, C13-norisoprenoids, volatile phenols, volatile fatty acids, lactones and carbonyl compounds) were determined in Albariño wines from different training systems, Vertical Shoot-Positioned (VSP), Scott-Henry (SH), Geneva Double-Curtain (GDC), Arch-Cane (AC), and Parral (P) during 2010 and 2011 vintages. Wines from GDC showed the highest total volatile composition with the highest concentrations of alcohols, ethyl esters, fatty acids, and lactones families. However, the highest levels of terpenes and C13-norisoprenoids were quantified in the SH system. A fruitier aroma was observed in Albariño wines from GDC when odor activity values were calculated.
Wound Healing Potential of Chlorogenic Acid and Myricetin-3-O-β-Rhamnoside Isolated from Parrotia persica
Authors: Moghadam Sara , Ebrahimi Samad , Salehi Peyman , Moridi Farimani Mahdi , Hamburger Matthias , Jabbarzadeh Ehsan
Published: September 2017

Wound healing is a complex physiological process that is controlled by a well-orchestrated cascade of interdependent biochemical and cellular events, which has spurred the development of therapeutics that simultaneously target these active cellular constituents. We assessed the potential of Parrotia persica (Hamamelidaceae) in wound repair by analyzing the regenerative effects of its two main phenolic compounds, myricetin-3-O-β-rhamnoside and chlorogenic acid. To accomplish this, we performed phytochemical profiling and characterized the chemical structure of pure compounds isolated from P. persica, followed by an analysis of the biological effects of myricetin-3-O-β-rhamnoside and chlorogenic acid on three cell types, including keratinocytes, fibroblasts, and endothelial cells. Myricetin-3-O-β-rhamnoside and chlorogenic acid exhibited complementary pro-healing properties. The percentage of keratinocyte wound closure as measured by a scratch assay was four fold faster in the presence of 10 µg/mL chlorogenic acid, as compared to the negative control. On the other hand, myricetin-3-O-β-rhamnoside at 10 µg/mL was more effective in promoting fibroblast migration, demonstrating a two-fold higher rate of closure compared to the negative control group. Both compounds enhanced the capillary-like tube formation of endothelial cells in an in vitro angiogenesis assay. Our results altogether delineate the potential to synergistically accelerate the fibroblastic and remodelling phases of wound repair by administering appropriate amounts of myricetin-3-O-β-rhamnoside and chlorogenic acid.
Senna singueana: Antioxidant, Hepatoprotective, Antiapoptotic Properties and Phytochemical Profiling of a Methanol Bark Extract
Authors: Sobeh Mansour , Mahmoud Mona , Hasan Rehab , Cheng Haroan , El-Shazly Assem , Wink Michael
Published: September 2017

Natural products are considered as an important source for the discovery of new drugs to treat aging-related degenerative diseases and liver injury. The present study profiled the chemical constituents of a methanol extract from Senna singueana bark using HPLC-PDA-ESI-MS/MS and 36 secondary metabolites were identified. Proanthocyanidins dominated the extract. Monomers, dimers, trimers of (epi)catechin, (epi)gallocatechin, (epi)guibourtinidol, (ent)cassiaflavan, and (epi)afzelechin represented the major constituents. The extract demonstrated notable antioxidant activities in vitro: In DPPH (EC50 of 20.8 µg/mL), FRAP (18.16 mM FeSO4/mg extract) assays, and total phenolic content amounted 474 mg gallic acid equivalent (GAE)/g extract determined with the Folin-Ciocalteu method. Also, in an in vivo model, the extract increased the survival rate of Caenorhabditis elegans worms pretreated with the pro-oxidant juglone from 43 to 64%, decreased intracellular ROS inside the wild-type nematodes by 47.90%, and induced nuclear translocation of the transcription factor DAF-16 in the transgenic strain TJ356. Additionally, the extract showed a remarkable hepatoprotective activity against d-galactosamine (d-GalN) induced hepatic injury in rats. It significantly reduced elevated AST (aspartate aminotransferase), and total bilirubin. Moreover, the extract induced a strong cytoplasmic Bcl-2 expression indicating suppression of apoptosis. In conclusion, the bark extract of S. sengueana represents an interesting candidate for further research in antioxidants and liver protection.
Detecting Drought-Induced Tree Mortality in Sierra Nevada Forests with Time Series of Satellite Data
Authors: Byer Sarah , Jin Yufang
Published: September 2017

A five-year drought in California led to a significant increase in tree mortality in the Sierra Nevada forests from 2012 to 2016. Landscape level monitoring of forest health and tree dieback is critical for vegetation and disaster management strategies. We examined the capability of multispectral imagery from the Moderate Resolution Imaging Spectroradiometer (MODIS) in detecting and explaining the impacts of the recent severe drought in Sierra Nevada forests. Remote sensing metrics were developed to represent baseline forest health conditions and drought stress using time series of MODIS vegetation indices (VIs) and a water index. We used Random Forest algorithms, trained with forest aerial detection surveys data, to detect tree mortality based on the remote sensing metrics and topographical variables. Map estimates of tree mortality demonstrated that our two-stage Random Forest models were capable of detecting the spatial patterns and severity of tree mortality, with an overall producer’s accuracy of 96.3% for the classification Random Forest (CRF) and a RMSE of 7.19 dead trees per acre for the regression Random Forest (RRF). The overall omission errors of the CRF ranged from 19% for the severe mortality class to 27% for the low mortality class. Interpretations of the models revealed that forests with higher productivity preceding the onset of drought were more vulnerable to drought stress and, consequently, more likely to experience tree mortality. This method highlights the importance of incorporating baseline forest health data and measurements of drought stress in understanding forest response to severe drought.
A Feasibility Study of Sea Ice Motion and Deformation Measurements Using Multi-Sensor High-Resolution Optical Satellite Images
Authors: Hyun Chang-Uk , Kim Hyun-cheol
Published: September 2017

Sea ice motion and deformation have generally been measured using low-resolution passive microwave or mid-resolution radar remote sensing datasets of daily (or few days) intervals to monitor long-term trends over a wide polar area. This feasibility study presents an application of high-resolution optical images from operational satellites, which have become more available in polar regions, for sea ice motion and deformation measurements. The sea ice motion, i.e., Lagrangian vector, is measured by using a maximum cross-correlation (MCC) technique and multi-temporal high-resolution images acquired on 14–15 August 2014 from multiple spaceborne sensors on board Korea Multi-Purpose Satellites (KOMPSATs) with short acquisition time intervals. The sea ice motion extracted from the six image pairs of the spatial resolutions were resampled to 4 m and 15 m yields with vector length measurements of 57.7 m root mean square error (RMSE) and −11.4 m bias and 60.7 m RMSE and −13.5 m bias, respectively, compared with buoy location records. The errors from both resolutions indicate more accurate measurements than from conventional sea ice motion datasets from passive microwave and radar data in ice and water mixed surface conditions. In the results of sea ice deformation caused by interaction of individual ice floes, while free drift patterns of ice floes were delineated from the 4 m spatial resolution images, the deformation was less revealing in the 15 m spatial resolution image pairs due to emphasized discretization uncertainty from coarser pixel sizes. The results demonstrate that using multi-temporal high-resolution optical satellite images enabled precise image block matching in the melting season, thus this approach could be used for expanding sea ice motion and deformation dataset, with an advantage of frequent image acquisition capability in multiple areas by means of many operational satellites.
Thermal Flow Sensors for Harsh Environments
Authors: Balakrishnan Vivekananthan , Phan Hoang-Phuong , Dinh Toan , Dao Dzung , Nguyen Nam-Trung
Published: September 2017

Flow sensing in hostile environments is of increasing interest for applications in the automotive, aerospace, and chemical and resource industries. There are thermal and non-thermal approaches for high-temperature flow measurement. Compared to their non-thermal counterparts, thermal flow sensors have recently attracted a great deal of interest due to the ease of fabrication, lack of moving parts and higher sensitivity. In recent years, various thermal flow sensors have been developed to operate at temperatures above 500 °C. Microelectronic technologies such as silicon-on-insulator (SOI), and complementary metal-oxide semiconductor (CMOS) have been used to make thermal flow sensors. Thermal sensors with various heating and sensing materials such as metals, semiconductors, polymers and ceramics can be selected according to the targeted working temperature. The performance of these thermal flow sensors is evaluated based on parameters such as thermal response time, flow sensitivity. The data from thermal flow sensors reviewed in this paper indicate that the sensing principle is suitable for the operation under harsh environments. Finally, the paper discusses the packaging of the sensor, which is the most important aspect of any high-temperature sensing application. Other than the conventional wire-bonding, various novel packaging techniques have been developed for high-temperature application.
A Tailored Ontology Supporting Sensor Implementation for the Maintenance of Industrial Machines
Authors: Maleki Elaheh , Belkadi Farouk , Ritou Mathieu , Bernard Alain
Published: September 2017

The longtime productivity of an industrial machine is improved by condition-based maintenance strategies. To do this, the integration of sensors and other cyber-physical devices is necessary in order to capture and analyze a machine’s condition through its lifespan. Thus, choosing the best sensor is a critical step to ensure the efficiency of the maintenance process. Indeed, considering the variety of sensors, and their features and performance, a formal classification of a sensor’s domain knowledge is crucial. This classification facilitates the search for and reuse of solutions during the design of a new maintenance service. Following a Knowledge Management methodology, the paper proposes and develops a new sensor ontology that structures the domain knowledge, covering both theoretical and experimental sensor attributes. An industrial case study is conducted to validate the proposed ontology and to demonstrate its utility as a guideline to ease the search of suitable sensors. Based on the ontology, the final solution will be implemented in a shared repository connected to legacy CAD (computer-aided design) systems. The selection of the best sensor is, firstly, obtained by the matching of application requirements and sensor specifications (that are proposed by this sensor repository). Then, it is refined from the experimentation results. The achieved solution is recorded in the sensor repository for future reuse. As a result, the time and cost of the design process of new condition-based maintenance services is reduced.
Life Cycle Impact Assessment in the Arctic: Challenges and Research Needs
Authors: Pettersen Johan , Song Xingqiang
Published: September 2017

Life cycle assessment (LCA) is increasingly used for environmental assessment of products and production processes to support environmental decision-making both worldwide and in the Arctic. However, there are several weaknesses in the impact assessment methodology in LCA, e.g., related to uncertainties of impact assessment results, absence of spatial differentiation in characterization modeling, and gaps in the coverage of impact pathways of different “archetypal” environments. Searching for a new resource base and areas for operation, marine and marine-based industries are continuously moving north, which underlines the need for better life cycle impact assessment in the Arctic, particularly to aid in industrial environmental management systems and stakeholder communications. This paper aims to investigate gaps and challenges in the application of the currently available impact assessment methods in the Arctic context. A simplified Arctic mining LCA case study was carried out to demonstrate the relevance of Arctic emissions at the midpoint and endpoint levels, as well as possible influences of the Arctic context on the impact assessment results. Results of this study showed that significant research gaps remain in Arctic-dependent life cycle impact assessment, particularly on: (i) the possible influences of the Arctic-specific features on characterization factors for impact assessment (such as seasonality, cold climate, precipitation, and marine dependence); and (ii) the coverage of impact pathways, especially on the under-addressed marine impacts and marine/near-shore dispersion processes. Addressing those identified research gaps and demand for future Arctic life cycle impact assessment could increase the credibility of LCA as an environmental decision-making support tool for Arctic industries and better support sustainable Arctic development.
Study on the Climate Adaption Planning for an Industrial Company with Regional Risk of the Water Supply System—A Case in Taiwan
Authors: Chen Pei-Yuan , Huang Syu-Jie , Yu Chia-Yii , Chiang Pen-Chi , Liu Tzu-Ming , Tung Ching-Pin
Published: September 2017

Extreme uneven spatial and temporal distributions of rainfall pose the risk of water shortage to the industries in Taiwan, particularly during dry seasons, which may be worsen under climate change. This study aims to develop adaptation actions for an industrial company to reduce the risk of droughts. The Formosa Plastics Corporation (FPC) in Chuoshui River watershed is selected as a study case and an integrated risk assessment tool of water resources TaiWAP is used. The water shortage of FPC is mainly in the dry seasons because the water rights of public and agricultural uses are prioritized over industrial use. The considered adaptation options including water reuse, a desalination plant, smart agricultural water management, and rainwater harvesting. The results show that the waste-water reuse and sea-water desalination are the most effective adaptation options, which reduces the water shortage risks 33–44% per day in the return period of ten years. The results are generalized for the reference of other studies. The risk assessment and adaptation measure identification of the company require regional information. Moreover, some adaptation measures that the company implements help reduce the water shortage of the region and are consequently beneficial to the company, e.g., smart agricultural water management.
Estimation of Sediment Yield Change in a Loess Plateau Basin, China
Authors: Zhang Ling , Karthikeyan Raghupathy , Zhang Hui , Tang Yuxuan
Published: September 2017

Soil erosion is one of the most serious land degradation problems and the primary environmental issue in the Loess Plateau region of China. To identify the critical sub-basins and assess the impacts of land use change and climatic variability change on soil loss, this study tested the feasibility of the Soil and Water Assessment Tool (SWAT) model on sediment load simulation in the upper Sang-kan (USK) River basin. Based on a land use map of 1986, the SWAT model (Scenario 0) was calibrated at a monthly step using climate data from 1979 to 1985; then it was validated using climate data from 1986 to 1990. The monthly sediment simulation results indicated that the model did not work as well as streamflow simulation, indicating lower NS (Nash-Sutcliffe Efficiency) and r2 values of 0.68, 0.69 and 0.61, 0.59 for the calibration period and validation period, respectively. This model could perform well under relatively low rainfall events, but it underestimated or overestimated the sediment load under high rainfall events. Comparing the results of scenarios with different land use maps (year of 1986 vs. 2012) and climate periods (1979–1990 vs. 2001–2012), it can be concluded that: (i) extreme and severe erosion almost always happened in FRST (forest land) and RNGE (grassland) in the hilly area; (ii) long-term traditional farming weakens the soil anti-erosion capability of land, leading to higher soil erosion, while forest can improve the soil structure, enhance the soil anti-erosion capability, and reduce soil erosion; (iii) both land use change and climatic change have led to the sediment yield decrease in the USK basin. Acting as the major influencing factor, land use change contributed to about 64.9% of the sediment yield reduction in the USK river basin.
Simulating Laboratory Braided Rivers with Bed-Load Sediment Transport
Authors: Yang Haiyan , Lin Binliang , Sun Jian , Huang Guoxian
Published: September 2017

Numerical models provide considerable assistance in the investigation of complicated processes in natural rivers. In the present study, a physics-based two-dimensional model has been developed to simulate the braiding processes and morphodynamic changes in braided rivers. The model applies the basic hydrodynamic and sediment transport principles with bed morphology deformation and a TVD (Total Variation Diminishing) scheme to predict trans-critical flows and bed morphology deformation. The non-equilibrium transport process of graded bed load sediment is simulated, with non-uniform sediments, secondary flows, and sheltering effects being included. A multiple bed layer technique is adopted to represent the vertical sediment sorting process. The model has been applied to simulate the bed evolution process in an experimental river with bed load transport. Comparisons between the experimental river and predicted river are analysed, including their pattern evolution processes, important braiding phenomena, and statistical characteristics. Avulsion activities have been found in the braiding evolution process, representing the primary ways in which channels form and disappear in braided rivers. The increases in the active braiding intensity and total braiding intensity show similar trends to those observed in the experimental river. Statistical methods are applied to assess the scale-invariant topographic properties of the simulated river and real rivers. The model demonstrated its potential to predict the morphodynamics in natural rivers.
Relaxation near Supermassive Black Holes Driven by Nuclear Spiral Arms: Anisotropic Hypervelocity Stars, S-stars, and Tidal Disruption Events
Authors: Hamers Adrian S. , Perets Hagai B.
Published: September 2017

Nuclear spiral arms are small-scale transient spiral structures found in the centers of galaxies. Similarly to their galactic-scale counterparts, nuclear spiral arms can perturb the orbits of stars. In the case of the Galactic center (GC), these perturbations can affect the orbits of stars and binaries in a region extending to several hundred parsecs around the supermassive black hole (SMBH), causing diffusion in orbital energy and angular momentum. This diffusion process can drive stars and binaries to close approaches with the SMBH, disrupting single stars in tidal disruption events (TDEs), or disrupting binaries, leaving a star tightly bound to the SMBH and an unbound star escaping the galaxy, i.e., a hypervelocity star (HVS). Here, we consider diffusion by nuclear spiral arms in galactic nuclei, specifically the Milky Way GC. We determine nuclear-spiral-arm-driven diffusion rates using test-particle integrations and compute disruption rates. Our TDE rates are up to 20% higher compared to relaxation by single stars. For binaries, the enhancement is up to a factor of ∼100, and our rates are comparable to the observed numbers of HVSs and S-stars. Our scenario is complementary to relaxation driven by massive perturbers. In addition, our rates depend on the inclination of the binary with respect to the Galactic plane. Therefore, our scenario provides a novel potential source for the observed anisotropic distribution of HVSs. Nuclear spiral arms may also be important for accelerating the coalescence of binary SMBHs and for supplying nuclear star clusters with stars and gas.
The JCMT BISTRO Survey: The Magnetic Field Strength in the Orion A Filament
Authors: Pattle Kate , Ward-Thompson Derek , Berry David , Hatchell Jennifer , Chen Huei-Ru , Pon Andy , Koch Patrick M. , Kwon Woojin , Kim Jongsoo , Bastien Pierre , Cho Jungyeon , Coudé Simon , Di Francesco James , Fuller Gary , Furuya Ray S. , Graves Sarah F. , Johnstone Doug , Kirk Jason , Kwon Jungmi , Lee Chang Won , Matthews Brenda C. , Mottram Joseph C. , Parsons Harriet , Sadavoy Sarah , Shinnaga Hiroko , Soam Archana , Hasegawa Tetsuo , Lai Shih-Ping , Qiu Keping , Friberg Per
Published: September 2017

We determine the magnetic field strength in the OMC 1 region of the Orion A filament via a new implementation of the Chandrasekhar–Fermi method using observations performed as part of the James Clerk Maxwell Telescope (JCMT) B-Fields In Star-forming Region Observations (BISTRO) survey with the POL-2 instrument. We combine BISTRO data with archival SCUBA-2 and HARP observations to find a plane-of-sky magnetic field strength in OMC 1 of

mG, where

mG represents a predominantly systematic uncertainty. We develop a new method for measuring angular dispersion, analogous to unsharp masking. We find a magnetic energy density of

J m−3 in OMC 1, comparable both to the gravitational potential energy density of OMC 1 (∼10−7 J m−3) and to the energy density in the Orion BN/KL outflow (∼10−7 J m−3). We find that neither the Alfvén velocity in OMC 1 nor the velocity of the super-Alfvénic outflow ejecta is sufficiently large for the BN/KL outflow to have caused large-scale distortion of the local magnetic field in the ∼500 yr lifetime of the outflow. Hence, we propose that the hourglass field morphology in OMC 1 is caused by the distortion of a primordial cylindrically symmetric magnetic field by the gravitational fragmentation of the filament and/or the gravitational interaction of the BN/KL and S clumps. We find that OMC 1 is currently in or near magnetically supported equilibrium, and that the current large-scale morphology of the BN/KL outflow is regulated by the geometry of the magnetic field in OMC 1, and not vice versa.
A Multi-band Study of the Remarkable Jet in Quasar 4C+19.44
Authors: Harris D. E. , Lee N. P. , Schwartz D. A. , Siemiginowska A. , Massaro F. , Birkinshaw M. , Worrall D. M. , Cheung C. C. , Gelbord J. M. , Jorstad Svetlana G. , Marscher Alan P. , Landt H. , Marshall H. , Perlman E. S. , Stawarz L. , Uchiyama Y. , Urry C. M.
Published: September 2017

We present arcsecond-resolution data in the radio, IR, optical, and X-ray for 4C+19.44 (=PKS 1354+195), the longest and straightest quasar jet with deep X-ray observations. We report results from radio images with half to one arcsecond angular resolution at three frequencies, plus Hubble Space Telescope and Spitzer data. The Chandra data allow us to measure the X-ray spectral index in 10 distinct regions along the 18″ jet and compare with the radio index. The radio and X-ray spectral indices of the jet regions are consistent with a value of

throughout the jet, to within

uncertainties. The X-ray jet structure to the south extends beyond the prominent radio jet and connects to the southern radio lobe, and there is extended X-ray emission, both in the direction of the unseen counter-jet, and also coincident with the northern radio lobe. This jet is remarkable because its straight appearance over a large distance allows the geometry factors to be taken as fixed along the jet. Using the model of inverse Compton scattering of the cosmic microwave background (iC/CMB) by relativistic electrons, we find that the magnetic field strengths and Doppler factors are relatively constant along the jet. If instead the X-rays are synchrotron emission, they must arise from a population of electrons distinct from the particles producing the radio synchrotron spectrum.
Rapid X-Ray Variations of the Geminga Pulsar Wind Nebula
Authors: Hui C. Y. , Lee Jongsu , Kong A. K. H. , Tam P. H. T. , Takata J. , Cheng K. S. , Ryu Dongsu
Published: September 2017

A recent study by Posselt et al. reported the deepest X-ray investigation of the Geminga pulsar wind nebula (PWN) by using Chandra X-ray Observatory. In comparison with previous studies of this system, a number of new findings have been reported, and we found that these suggest the possible variabilities in various components of this PWN. This motivates us to carry out a dedicated search for the morphological and spectral variations of this complex nebula. We have discovered variabilities on timescales from a few days to a few months from different components of the nebula. The fastest change occurred in the circumstellar environment at a rate of 80% of the speed of light. One of the most spectacular results is the wiggling of a half light-year long tail as an extension of the jet, which is significantly bent by the ram pressure. The jet wiggling occurred at a rate of about 20% of the speed of light. This twisted structure could possibly be a result of a propagating torsional Alfv́en wave. We have also found evidence of spectral hardening along this tail for a period of about nine months.
Le rôle des Technologies de l’Information et de la Communication dans la dynamique d’un réseau d’innovation : une approche ANT
Authors: Fuhrer Chantal , Hoareau Émilie , Cucchi Alain
Published: September 2017

L’objectif de cette étude est de mieux comprendre la dynamique d’un réseau d’innovation et plus particulièrement le rôle des Technologies de l’Information et de la Communication (TIC) dans cette dynamique. Une approche Actor-Network Theory (ANT) est mobilisée. Le terrain d’investigation, QualiREG 1 , est un réseau d’innovation unissant les acteurs de territoires de l’Océan Indien. L’analyse des témoignages des acteurs montre que les TIC interviennent différemment tout au long du cycle. Ainsi les Technologies de l’Information (TI) et le face-à-face permettent l’exploration de l’environnement et la mobilisation des ressources des innovateurs. Les Technologies de la Communication (TC) activent le lien qui les unit. Des recherches supplémentaires sont nécessaires avant de généraliser les résultats de cette étude de cas. Néanmoins, elle apporte une approche complémentaire autour du débat sur les liens entre l’innovation et la technologie. Codes JEL : M, O