bluuebunny/crossref_metadata_2025 huggingface dataset:
Design and Stiffness Evaluation of a Compliant Joint with Parallel Architecture Realizing an Approximately Spherical Motion
Authors: Parvari Rad Farid , Vertechy Rocco , Berselli Giovanni , Parenti-Castelli Vincenzo
Published: April 2018

This paper introduces the design of a fully-compliant Spherical Joint (SJ), obtained by the in-parallel connection of two identical open chains each composed of three equal circular flexible beams, having coincident centers of curvature and mutually orthogonal axes of minimum rotational stiffness. Thanks to its particular topology, the SJ provides a fully isotropic behavior, the two chains being placed in space so as to be symmetric with respect to the beams’ center of curvature. At first, the overall system compliance matrix is derived by means of an analytical procedure, in order to obtain a parametric formulation of the SJ behavior within the small deflection range. Then, after finite element validation of the analytical model, an optimization study of the beam geometry is developed, with the aim of maximizing the ratio between the SJ primary to secondary compliance factors. At last, the potential advantages and drawbacks of the proposed design are discussed by numerically evaluating the joint performance in terms of parasitic motions within the large deflection range (namely, when large external loads are applied to the envisaged center of spherical motion).
Glutathione: Antioxidant Properties Dedicated to Nanotechnologies
Authors: Gaucher Caroline , Boudier Ariane , Bonetti Justine , Clarot Igor , Leroy Pierre , Parent Marianne
Published: April 2018

Which scientist has never heard of glutathione (GSH)? This well-known low-molecular-weight tripeptide is perhaps the most famous natural antioxidant. However, the interest in GSH should not be restricted to its redox properties. This multidisciplinary review aims to bring out some lesser-known aspects of GSH, for example, as an emerging tool in nanotechnologies to achieve targeted drug delivery. After recalling the biochemistry of GSH, including its metabolism pathways and redox properties, its involvement in cellular redox homeostasis and signaling is described. Analytical methods for the dosage and localization of GSH or glutathiolated proteins are also covered. Finally, the various therapeutic strategies to replenish GSH stocks are discussed, in parallel with its use as an addressing molecule in drug delivery.
Synthesis, Characterization, and Self-Assembly of a Tetrathiafulvalene (TTF)–Triglycyl Derivative
Authors: Pérez-Rentero Sónia , Eritja Ramon , Häring Marleen , Saldías César , Díaz David Díaz
Published: April 2018

In this work, we describe the synthesis, characterization, and self-assembly properties of a new tetrathiafulvalene (TTF)–triglycyl low-molecular-weight (LMW) gelator. Supramolecular organogels were obtained in various solvents via a heating–cooling cycle. Critical gelation concentrations (CGC) (range ≈ 5–50 g/L) and thermal gel-to-sol transition temperatures (Tgel) (range ≈ 36–51 °C) were determined for each gel. Fourier transform infrared (FT-IR) spectroscopy suggested that the gelator is also aggregated in its solid state via a similar hydrogen-bonding pattern. The fibrillar microstructure and viscoelastic properties of selected gels were demonstrated by means of field-emission electron microscopy (FE-SEM) and rheological measurements. As expected, exposure of a model xerogel to I2 vapor caused the oxidation of the TTF unit as confirmed by UV-vis-NIR analysis. However, FT-IR spectroscopy showed that the oxidation was accompanied with concurrent alteration of the hydrogen-bonded network.
Noise Attenuation Based on Wave Vector Characteristics
Authors: Lu Jun , Wang Yun , Chen Jingyi
Published: April 2018

Polarization filtering has been widely used to enhance signal-to-noise ratios for multicomponent seismic data. Polarization filters routinely depend on the ellipticity and directionality of spatial particle motions. However, factors such as noise and formation heterogeneity often make the polarization characteristics of body waves hard to distinguish. Here, we introduce a technique in the time domain for the separation of valid body waves and noise based on wave vector characteristics. First, we characterise the ground-roll polarization by the median wave vectors derived in large-scale moving time windows. For the suppression of ground roll, we fit the particle trajectory of ground roll by the least square method using all components simultaneously. Second, we apply three-stage smoothing to the ground-roll-removed multicomponent records. In each stage, we use mean or median vectors derived in small-scale moving-time or moving-trace windows to attenuate random noise and other non-ground-roll related coherent noise. The filter in the proposed method is not devised according to ellipticity and directionality. Instead, we use the wave vector decomposition to distinguish between noise and valid signals. Synthetic data and field data examples confirm that the proposed method can effectively suppress noise without damaging the high and low frequencies of a valid signal.
Microstructure and Mechanical Properties of the Dactylopodites of the Chinese Mitten Crab (Eriocheir sinensis)
Authors: Wang Ying , Li Xiujuan , Li Jianqiao , Qiu Feng
Published: April 2018

The dactylopodites of the Chinese mitten crab (Eriocheir sinensis) have evolved extraordinary resistance to wear and impact loading after direct contact with rough surfaces or clashing with hard materials. In this study, the microstructure, components, and mechanical properties of the dactylopodites of the Chinese mitten crab were investigated. Images from a scanning electron microscope show that the dactylopodites’ exoskeleton was multilayered, with an epicuticle, exocuticle, and endocuticle. Cross sections and longitudinal sections of the endocuticle revealed a Bouligand structure, which contributes to the dactylopodites’ mechanical properties. The main organic constituents of the exoskeleton were chitin and protein, and the major inorganic compound was CaCO3, crystallized as calcite. Dry and wet dactylopodites were brittle and ductile, respectively, characteristics that are closely related to their mechanical structure and composition. The findings of this study can be a reference for the bionic design of strong and durable structural materials.
In Situ Experimental Study of the Friction of Sea Ice and Steel on Sea Ice
Authors: Wang Qingkai , Li Zhijun , Lu Peng , Cao Xiaowei , Leppäranta Matti
Published: April 2018

The kinetic coefficient of friction μk was measured for sea ice, stainless steel, and coated steel sliding on a natural sea ice cover. The effects of normal stress (3.10–8.11 kPa), ice columnar grain orientation (vertical and parallel to the sliding direction), sliding velocity (0.02–2.97 m·s–1), and contact material were investigated. Air temperature was higher than −5.0 °C for the test duration. The results showed a decline of μk with increasing normal stress with μk independent of ice grain orientation. The μk of different materials varied, partly due to distinct surface roughnesses, but all cases showed a similar increasing trend with increasing velocity because of the viscous resistance of melt-water film. The velocity dependence of μk was quantified using the rate- and state- dependent model, and μk was found to increase logarithmically with increasing velocity. In addition, μk obtained at higher air temperatures was greater than at lower temperatures. The stick-slip phenomenon was observed at a relatively high velocity compared with previous studies, which was partly due to the low-stiffness device used in the field. Based on the experimental data, the calculation of physical models can be compared.
Experimental Study of Ground Subsidence Mechanism Caused by Sewer Pipe Cracks
Authors: Karoui Tarek , Jeong Seong-Yun , Jeong Yeong-Hoon , Kim Dong-Soo
Published: April 2018

Simultaneous leakage of soil particles and groundwater into underground vacant spaces caused by sewer pipe defects and cracks can cause underground cavities and even ground collapse on the surface. Numerical studies of this problem are limited, and the mechanism of ground subsidence caused by leakage of soil and groundwater into construction sites has yet to be verified. In this study, the factors affecting the mechanism of ground subsidence are verified via physical modelling of a sewer pipe defect. Through visual inspection and particle image velocimetry analysis, it has been found that the groundwater flow direction, hydraulic gradient around the leakage point, and strength of the ground to support itself are the main factors that dominate the mechanism of ground subsidence. These factors can affect ground deformation and cavity expansion direction, ground subsidence development and collapse speed, and occurrence of sudden ground collapse, respectively. It was also found that pore pressure fluctuates when cavity cavern collapse and cavity expansion occur.
Experimental Analysis on Pre-Stress Friction Loss of Crushed Limestone Sand Concrete Beams
Authors: Xiao Yunfeng , Zhang Yaoting , Lu Jiezhi , Liu Yong , Cheng Wenjie
Published: April 2018

This paper presents an experimental research work that evaluates the pre-stress loss caused by friction in crushed limestone sand (CLS) concrete members with post-tensioning. A total of 26 full-scale pre-stressed concrete beams were constructed and tested for the friction loss experiment. The considered variables mainly included the duct-forming materials, wires of tendons and arrangement of ducts. The tensile forces at both active and passive ends of specimen were recorded by steps, and then the pre-stress friction loss for each case was calculated. The result shows that the proportion of pre-stress friction loss in specimen with multi-wire tendons is in the range of 10–40%, with the trend first increasing before decreasing. The pre-stress friction loss in specimen with curve duct accounts for 10–30%. The pressure on the curved part definitely increases the friction when compared with the straight duct. The pre-stress friction loss in specimen with rubber hose reaches nearly 40%, which is larger than the metal bellow and plastic bellow. The suggested values for each case are proposed for a deviation coefficient κ of 0.0017–0.007 and a friction coefficient μ of 0.108–0.858. This can provide reliable theoretical support for the design and construction.
Active Noise Control Using Modified FsLMS and Hybrid PSOFF Algorithm
Authors: Walia Ranjan , Ghosh Smarajit
Published: April 2018

Active noise control is an efficient technique for noise cancellation of the system, which has been defined in this paper with the aid of Modified Filtered-s Least Mean Square (MFsLMS) algorithm. The Hybrid Particle Swarm Optimization and Firefly (HPSOFF) algorithm are used to identify the stability factor of the MFsLMS algorithm. The computational difficulty of the modified algorithm is reduced when compared with the original Filtered-s Least Mean Square (FsLMS) algorithm. The noise sources are removed from the signal and it is compared with the existing FsLMS algorithm. The performance of the system is established with the normalized mean square error for two different types of noises. The proposed method has also been compared with the existing algorithms for the same purposes.
Circulating MicroRNA Biomarkers in Melanoma: Tools and Challenges in Personalised Medicine
Authors: Mumford Sophie L. , Towler Benjamin P. , Pashler Amy L. , Gilleard Onur , Martin Yella , Newbury Sarah F.
Published: April 2018

Effective management of melanoma depends heavily on early diagnosis. When detected in early non-metastatic stages, melanoma is almost 100% curable by surgical resection, however when detected in late metastatic stages III and IV, 5-year survival rates drop to ~50% and 10–25%, respectively, due to limited efficacy of current treatment options. This presents a pressing need to identify biomarkers that can detect patients at high risk of recurrence and progression to metastatic disease, which will allow for early intervention and survival benefit. Accumulating evidence over the past few decades has highlighted the potential use of circulating molecular biomarkers for melanoma diagnosis and prognosis, including lactate dehydrogenase (LDH), S100 calcium-binding protein B (S100B) and circulating tumor DNA (ctDNA) fragments. Since 2010, circulating microRNAs (miRNAs) have been increasingly recognised as more robust non-invasive biomarkers for melanoma due to their structural stability under the harsh conditions of the blood and different conditions of sample processing and isolation. Several pre-analytical and analytical variables challenge the accurate quantification of relative miRNA levels between serum samples or plasma samples, leading to conflicting findings between studies on circulating miRNA biomarkers for melanoma. In this review, we provide a critical summary of the circulating miRNA biomarkers for melanoma published to date.
Perceived Discrimination among Black Youth: An 18-Year Longitudinal Study
Authors: Assari Shervin , Gibbons Frederick X. , Simons Ronald L.
Published: April 2018

Background: Recent research has suggested vulnerability to perceived racial discrimination (PRD) as a mechanism behind high levels of depression seen in high socioeconomic status (SES) Black males. To better understand the effects of gender and SES on shaping experiences of PRD among Black youth in the United States, we used data from the Family and Community Health Study (FACHS) to explore the trajectory of PRD in Black youth by gender, SES, and place. Methods: Data came from FACHS, 1997–2017, which followed 889 children aged 10–12 years old at Wave 1 (n = 478; 53.8% females and n = 411; 46.2% males) for up to 18 years. Data were collected in seven waves. The main predictors of interest were gender, SES (parent education and annual family income), age, and place of residence. Main outcomes of interest were baseline and slope of PRD. Latent growth curve modeling (LGCM) was used for data analysis. Results: Gender, SES, place, and age were correlated with baseline and change in PRD over time. Male, high family income, and younger Black youth reported lower PRD at baseline but a larger increase in PRD over time. Youth who lived in Iowa (in a predominantly White area) reported higher PRD at baseline and also an increase in PRD over time. High parental education was not associated with baseline or change in PRD. Conclusion: In the United States, Black youth who are male, high income, and live in predominantly White areas experience an increase in PRD over time. Future research is needed on the interactions between gender, SES, and place on exposure and vulnerability of Black youth to PRD. Such research may explain the increased risk of depression in high SES Black males.
Carbon-Coated Nickel Nanoparticles: Effect on the Magnetic and Electric Properties of Composite Materials
Authors: Plyushch Artyom , Macutkevič Jan , Banys Jūras , Kuzhir Polina , Kalanda Nikolay , Petrov Alexander , Silvestre Clara , Uimin Mikhail A. , Yermakov Anatoly Ye. , Shenderova Olga
Published: April 2018

Nickel nanoparticles coated with few layers of carbon have been embedded into the polydimethylsiloxane (PDMS) matrix in concentrations up to 11 vol %. Dielectric and magnetic properties of composite materials have been studied in wide frequency (20 Hz–1 MHz) and temperature (130–430 K) ranges. It was demonstrated that the temperature behavior of dielectric properties is determined by glass transitions in the PDSM matrix below 200 K and the Maxwell–Wagner relaxation above room temperature. The possibility of using fabricated composites on the basis of the PDMS matrix for producing a wide range of passive electromagnetic components, such as frequency-selective filters, wide-band detectors/sensors of a bolometric type, and even electromagnetic “black holes” is also discussed.
Thermodynamic Behaviour of Mixed Films of an Unsaturated and a Saturated Polar Lipid. (Oleic Acid-Stearic Acid and POPC-DPPC)
Authors: Torrent-Burgués Juan
Published: April 2018

Mixed fatty acids or mixed phospholipids systems with saturated-unsaturated hydrocarbon chains are of biological interest. In this work, the monolayers of oleic acid-stearic acid (OA-SA) and palmitoyloleoylphosphatidylcholine-dipalmitoylphosphatidylcholine (POPC-DPPC) have been studied. From the surface pressure-area isotherms, elastic modulus values and virial equation coefficients can be obtained. Thermodynamic treatment also yields excess (GE) and mixing (ΔGmix) free energies. Results indicate positive GE values, that is, molecular interactions in the mixed films are less favourable, due to the presence of unsaturation; however, the mixture is slightly favourable due to the entropic factor that affords positive ΔGmix values. For the OA-SA system, a high SA content and surface pressure facilitate the phase separation, even though a certain miscibility between both components still remains. For the POPC-DPPC system, the most favourable mixing conditions occur for XPOPC ≈ 0.4. For these mixed systems, the values of the elastic modulus are more similar to those of more fluid components (OA or POPC); analysis of the virial coefficients shows that the b1 virial coefficient values lie between those of the individual components and are higher than values suitable for an ideal mixing.
Hepatitis C in Pregnancy
Authors: Dibba Pratima , Cholankeril Rosann , Li Andrew A. , Patel Meera , Fayek Mariam , Dibble Christy , Okpara Nnenna , Hines Autumn , Ahmed Aijaz
Published: April 2018

The prevalence of hepatitis C in pregnancy is as high as 3.6% in large cohorts. The prevalence of hepatitis C acquired by vertical transmission is 0.2% to 0.4% in the United States and Europe. Although screening is not recommended in the absence of certain risk factors, the importance of understanding hepatitis C in pregnancy lies in its association with adverse maternal and neonatal outcomes. There is potential for those infants infected by vertical transmission to develop chronic hepatitis C, cirrhosis or hepatocellular carcinoma. The risk of vertical transmission is increased when mothers are co-infected with Human Immunodeficiency Virus (HIV) or possess a high viral load. There is no clear data supporting that mode of delivery increases or reduces risk. Breastfeeding is not associated with increased risk of transmission. Premature rupture of membranes, invasive procedures (such as amniocentesis), intrapartum events, or fetal scalp monitoring may increase risk of transmission. In pregnant patients, hepatitis C is diagnosed with a positive ELISA-3 and detectable Hepatitis C Virus (HCV) RNA viral load. Infants born to HCV-infected mothers should be tested for either HCV RNA on at least two separate occasions. Although prevention is not possible, there may be a role for newer direct acting anti-viral medications in the future.
Self-Medication with Antibiotics, Attitude and Knowledge of Antibiotic Resistance among Community Residents and Undergraduate Students in Northwest Nigeria
Authors: Ajibola Olumide , Omisakin Olusola Akintoye , Eze Anthonius Anayochukwu , Omoleke Semeeh Akinwale
Published: April 2018

This study set out to evaluate self-medicated antibiotics and knowledge of antibiotic resistance among undergraduate students and community members in northern Nigeria. Antibiotic consumption pattern, source of prescription, illnesses commonly treated, attitude towards antibiotics, and knowledge of antibiotic resistance were explored using a structured questionnaire. Responses were analyzed and summarized using descriptive statistics. Of the 1230 respondents from undergraduate students and community members, prescription of antibiotics by a physician was 33% and 57%, respectively, amongst undergraduate students and community members. We tested the respondents’ knowledge of antibiotic resistance (ABR) and found that undergraduate students displayed less knowledge that self-medication could lead to ABR (32.6% and 42.2% respectively). Self-medication with antibiotics is highly prevalent in Northwest Nigeria, with most medicines being purchased from un-licensed stores without prescription from a physician. We also observed a significant gap in respondents’ knowledge of ABR. There is an urgent need for public health authorities in Nigeria to enforce existing laws on antibiotics sales and enlighten the people on the dangers of ABR.
Distributed One Time Password Infrastructure for Linux Environments
Authors: Benito Peral Alberto , Sandoval Orozco Ana Lucila , García Villalba Luis Javier , Kim Tai-Hoon
Published: April 2018

Nowadays, there is a lot of critical information and services hosted on computer systems. The proper access control to these resources is essential to avoid malicious actions that could cause huge losses to home and professional users. The access control systems have evolved from the first password based systems to the modern mechanisms using smart cards, certificates, tokens, biometric systems, etc. However, when designing a system, it is necessary to take into account their particular limitations, such as connectivity, infrastructure or budget. In addition, one of the main objectives must be to ensure the system usability, but this property is usually orthogonal to the security. Thus, the use of password is still common. In this paper, we expose a new password based access control system that aims to improve password security with the minimum impact in the system usability.
Finite Difference Method for Time-Space Fractional Advection–Diffusion Equations with Riesz Derivative
Authors: Arshad Sadia , Baleanu Dumitru , Huang Jianfei , Al Qurashi Maysaa Mohamed , Tang Yifa , Zhao Yue
Published: April 2018

In this article, a numerical scheme is formulated and analysed to solve the time-space fractional advection–diffusion equation, where the Riesz derivative and the Caputo derivative are considered in spatial and temporal directions, respectively. The Riesz space derivative is approximated by the second-order fractional weighted and shifted Grünwald–Letnikov formula. Based on the equivalence between the fractional differential equation and the integral equation, we have transformed the fractional differential equation into an equivalent integral equation. Then, the integral is approximated by the trapezoidal formula. Further, the stability and convergence analysis are discussed rigorously. The resulting scheme is formally proved with the second order accuracy both in space and time. Numerical experiments are also presented to verify the theoretical analysis.
Transfer Information Energy: A Quantitative Indicator of Information Transfer between Time Series
Authors: Caţaron Angel , Andonie Răzvan
Published: April 2018

We introduce an information-theoretical approach for analyzing information transfer between time series. Rather than using the Transfer Entropy (TE), we define and apply the Transfer Information Energy (TIE), which is based on Onicescu’s Information Energy. Whereas the TE can be used as a measure of the reduction in uncertainty about one time series given another, the TIE may be viewed as a measure of the increase in certainty about one time series given another. We compare the TIE and the TE in two known time series prediction applications. First, we analyze stock market indexes from the Americas, Asia/Pacific and Europe, with the goal to infer the information transfer between them (i.e., how they influence each other). In the second application, we take a bivariate time series of the breath rate and instantaneous heart rate of a sleeping human suffering from sleep apnea, with the goal to determine the information transfer heart → breath vs. breath → heart. In both applications, the computed TE and TIE values are strongly correlated, meaning that the TIE can substitute the TE for such applications, even if they measure symmetric phenomena. The advantage of using the TIE is computational: we can obtain similar results, but faster.
Against the Odds: Insights from a Statistician with Dyscalculia
Authors: Lewis Katherine E. , Lynn Dylan M.
Published: April 2018

Students with dyscalculia are typically thought of by both researchers and educators as having deficits. The deficit language permeates studies of dyscalculia as well as assessments and documentation of students in schools. In this paper, we offer an alternative to the dominant narrative. We understand disabilities, and dyscalculia specifically, as resulting from cognitive differences—not deficits—which lead to issues of access. We provide a case study of Dylan (second author), an individual with dyscalculia who decided to major in statistics at University of California, Berkeley and become a statistician. Although she experienced significant issues of access—both in the standard tools used to do mathematics, and in navigating the structures at the university—she developed systems to enable her to compensate. She collaborated in this research enterprise in order to share with researchers, teachers, parents, and students her experiences with dyscalculia and how she was able to succeed in higher level mathematics. Informed by previous empirical work, we collected video recordings of Dylan’s deliberate efforts to share insights and strategies with another student with dyscalculia. In this work, Dylan challenges dominant and problematic myths about ability and mathematics.
All-in-One Wafer-Level Solution for MMIC Automatic Testing
Authors: Ding Xu , Wang Zhiyu , Liu Jiarui , Zhou Min , Chen Wei , Chen Hua , Mo Jiongjiong , Yu Faxin
Published: April 2018

In this paper, we present an all-in-one wafer-level solution for MMIC (monolithic microwave integrated circuit) automatic testing. The OSL (open short load) two tier de-embedding, the calibration verification model, the accurate PAE (power added efficiency) testing, and the optimized vector cold source NF (noise figure) measurement techniques are integrated in this solution to improve the measurement accuracy. A dual-core topology formed by an IPC (industrial personal computer) and a VNA (vector network analyzer), and an automatic test software based on a three-level driver architecture, are applied to enhance the test efficiency. The benefit from this solution is that all the data of a MMIC can be achieved in only one contact, which shows state-of-the-art accuracy and efficiency.
Wireless Power Transfer System for Rotary Parts Telemetry of Gas Turbine Engine
Authors: He Xiaoming , Shu Wenjun , Yu Bing , Ma Xiaodong
Published: April 2018

A novel wireless power transfer approach for the rotary parts telemetry of a gas turbine engine is proposed. The advantages of a wireless power transfer (WPT) system in the power supply for the rotary parts telemetry of a gas turbine engine are introduced. By simplifying the circuit of the inductively-coupled WPT system and developing its equivalent circuit model, the mathematical expressions of transfer efficiency and transfer power of the system are derived. A mutual inductance model between receiving and transmitting coils of the WPT system is presented and studied. According to this model, the mutual inductance between the receiving and the transmitting coils can be calculated at different axial distances. Then, the transfer efficiency and transfer power can be calculated as well. Based on the test data, the relationship of the different distances between the two coils, the transfer efficiency, and transfer power is derived. The proper positions where the receiving and transmitting coils are installed in a gas turbine engine are determined under conditions of satisfying the transfer efficiency and transfer power that the telemetry system required.
Radar Waveform Recognition Based on Time-Frequency Analysis and Artificial Bee Colony-Support Vector Machine
Authors: Liu Lutao , Wang Shuang , Zhao Zhongkai
Published: April 2018

In this paper, a system for identifying eight kinds of radar waveforms is explored. The waveforms are the binary phase shift keying (BPSK), Costas codes, linear frequency modulation (LFM) and polyphase codes (including P1, P2, P3, P4 and Frank codes). The features of power spectral density (PSD), moments and cumulants, instantaneous properties and time-frequency analysis are extracted from the waveforms and three new features are proposed. The classifier is support vector machine (SVM), which is optimized by artificial bee colony (ABC) algorithm. The system shows well robustness, excellent computational complexity and high recognition rate under low signal-to-noise ratio (SNR) situation. The simulation results indicate that the overall recognition rate is 92% when SNR is −4 dB.
A Novel Dual-Scale Deep Belief Network Method for Daily Urban Water Demand Forecasting
Authors: Xu Yuebing , Zhang Jing , Long Zuqiang , Chen Yan
Published: April 2018

Water demand forecasting applies data supports for the scheduling and decision-making of urban water supply systems. In this study, a new dual-scale deep belief network (DSDBN) approach for daily urban water demand forecasting was proposed. Original daily water demand time series was decomposed into several intrinsic mode functions (IMFs) and one residue component with ensemble empirical mode decomposition (EEMD) technique. Stochastic and deterministic terms were reconstructed through analyzing the frequency characteristics of IMFs and residue using generalized Fourier transform. The deep belief network (DBN) model was used for prediction using the two feature terms. The outputs of the double DBNs are summed as the final forecasting results. Historical daily water demand datasets from an urban waterworks in Zhuzhou, China, were investigated by the proposed DSDBN model. The mean absolute percentage error (MAPE), normalized root-mean-square error (NRMSE), correlation coefficient (CC) and determination coefficient (DC) were used as evaluation criteria. The results were compared with the autoregressive integrated moving average (ARIMA) model, feed forward neural network (FFNN) model, support vector regression (SVR) model, EEMD and their combinations, and single DBN model. The results obtained in the test period indicate that the proposed model has the smallest MAPE and NRMSE values of 1.291099 and 0.016625, respectively, and the largest CC and DC values of 0.976528 and 0.953512, respectively. Therefore, the proposed DSDBN method is a useful tool for daily urban water demand forecasting and outperforms other models in common use.
Review of Voltage and Frequency Grid Code Specifications for Electrical Energy Storage Applications
Authors: Luo Xing , Wang Jihong , Wojcik Jacek D. , Wang Jianguo , Li Decai , Draganescu Mihai , Li Yaowang , Miao Shihong
Published: April 2018

To ensure the stability and reliability of the power network operation, a number of Grid Codes have been used to specify the technical boundary requirements for different countries and areas. With the fast propagation of the usage of Electrical Energy Storage (EES), it is quite important to study how the EES technology with its development can help the Grid Code realization. The paper provides a comprehensive study of Great Britain (GB) Grid Code mainly on its voltage and frequency relevant specifications, with a comparison of other countries’ grid operation regulations. The different types of EES technologies with their technical characteristics in relation to meeting Grid Codes have been analysed. From the study, apart from direct grid-connection to provide grid services on meeting Grid Codes, EES devices with different technologies can be used as auxiliary units in fossil-fuelled power plants and renewable generation to support the whole systems’ operation. The paper also evaluates the potentials of different types of EES technologies for implementing the relevant applications based on the Grid Codes. Some recommendations are given at the end, for the EES technology development to help the Grid Code realization and to support the relevant applications.
Analysis of Syngas Production from Biogas via the Tri-Reforming Process
Authors: Chein Rei-Yu , Hsu Wen-Hwai
Published: April 2018

The tri-reforming process was employed for syngas production from biogas at elevated pressures in this study. In the tri-reforming process, air and water were added simultaneously as reactants in addition to the main biogas components. The effects of various operating parameters such as pressure, temperature and reactant composition on the reaction performance were studied numerically. From the simulated results, it was found that methane and carbon dioxide conversions can be enhanced and a higher hydrogen/carbon monoxide ratio can be obtained by increasing the amount of air. However, a decreased hydrogen yield could result due to the reverse water–gas shift reaction. A higher level of methane conversion and hydrogen/carbon monoxide ratio can be obtained with increased water addition. However, negative carbon dioxide conversion could result due to the water–gas shift and reverse carbon dioxide methanation reactions. The dry reforming reaction resulting in positive carbon dioxide conversion can only be found at a high reaction temperature. For all cases studied, low or negative carbon dioxide conversion was found because of carbon dioxide production from methane oxidation, water–gas shift, and reverse carbon dioxide methanation reactions. It was found that carbon dioxide conversion can be enhanced in the tri-reforming process by a small amount of added water. It was also found that first-law efficiency increased with increased reaction temperature because of higher hydrogen and carbon monoxide yields. Second-law efficiency was found to decrease with increased temperature because of higher exergy destruction due to a more complete chemical reaction at high temperatures.
Triple Line-Voltage Cascaded VIENNA Converter Applied as the Medium-Voltage AC Drive
Authors: Zou Jia , Wang Cong , Cheng Hong , Liu Jinqi
Published: April 2018

A novel rectifier based on a triple line-voltage cascaded VIENNA converter (LVC-VC) was proposed. Compared to the conventional cascaded H-bridge converters, the switch voltage stress is lower, and the numbers of switches and dc capacitors are fewer under similar operating conditions in the proposed new multilevel converter. The modeling and control for the LVC-VC ware presented. Based on the analysis of the operation principle of the new converter, the power factor correction of the proposed converter was realized by employing a traditional one-cycle control strategy. The minimum average value and maximum harmonic components of the dc-link voltages of the three VIENNA rectifier modules ware calculated. Three VIENNA dc-link voltages were unbalanced under the unbalanced load conditions, so the zero sequence current was injected to the three inner currents for balancing three VIENNA dc-link voltages. Simulation and the results of the experiment verified the availability of the new proposed multilevel converter and the effectiveness of the corresponding control strategy applied.
Economics of Renewable Energy Integration and Energy Storage via Low Load Diesel Application
Authors: Hamilton James , Negnevitsky Michael , Wang Xiaolin
Published: April 2018

One-quarter of the world’s population lives without access to electricity. Unfortunately, the generation technology most commonly employed to advance rural electrification, diesel generation, carries considerable commercial and ecological risks. One approach used to address both the cost and pollution of diesel generation is renewable energy (RE) integration. However, to successfully integrate RE, both the stochastic nature of the RE resource and the operating characteristics of diesel generation require careful consideration. Typically, diesel generation is configured to run heavily loaded, achieving peak efficiencies within 70–80% of rated capacity. Diesel generation is also commonly sized to peak demand. These characteristics serve to constrain the possible RE penetration. While energy storage can relieve the constraint, this adds cost and complexity to the system. This paper identifies an alternative approach, redefining the low load capability of diesel generation. Low load diesel (LLD) allows a diesel engine to operate across its full capacity in support of improved RE utilization. LLD uses existing diesel assets, resulting in a reduced-cost, low-complexity substitute. This paper presents an economic analysis of LLD, with results compared to conventional energy storage applications. The results identify a novel pathway for consumers to transition from low to medium levels of RE penetration, without additional cost or system complexity.
Ex Machina: Analytical platforms, Law and the Challenges of Computational Legal Science
Authors: Lettieri Nicola , Altamura Antonio , Giugno Rosalba , Guarino Alfonso , Malandrino Delfina , Pulvirenti Alfredo , Vicidomini Francesco , Zaccagnino Rocco
Published: April 2018

Over the years, computation has become a fundamental part of the scientific practice in several research fields that goes far beyond the boundaries of natural sciences. Data mining, machine learning, simulations and other computational methods lie today at the hearth of the scientific endeavour in a growing number of social research areas from anthropology to economics. In this scenario, an increasingly important role is played by analytical platforms: integrated environments allowing researchers to experiment cutting-edge data-driven and computation-intensive analyses. The paper discusses the appearance of such tools in the emerging field of computational legal science. After a general introduction to the impact of computational methods on both natural and social sciences, we describe the concept and the features of an analytical platform exploring innovative cross-methodological approaches to the academic and investigative study of crime. Stemming from an ongoing project involving researchers from law, computer science and bioinformatics, the initiative is presented and discussed as an opportunity to raise a debate about the future of legal scholarship and, inside of it, about the challenges of computational legal science.
Bifurcation Mechanism Design—From Optimal Flat Taxes to Better Cancer Treatments
Authors: Yang Ger , Basanta David , Piliouras Georgios
Published: April 2018

Small changes to the parameters of a system can lead to abrupt qualitative changes of its behavior, a phenomenon known as bifurcation. Such instabilities are typically considered problematic, however, we show that their power can be leveraged to design novel types of mechanisms. Hysteresis mechanisms use transient changes of system parameters to induce a permanent improvement to its performance via optimal equilibrium selection. Optimal control mechanisms induce convergence to states whose performance is better than even the best equilibrium. We apply these mechanisms in two different settings that illustrate the versatility of bifurcation mechanism design. In the first one we explore how introducing flat taxation could improve social welfare, despite decreasing agent “rationality,” by destabilizing inefficient equilibria. From there we move on to consider a well known game of tumor metabolism and use our approach to derive potential new cancer treatment strategies.
Reactive Chemicals and Electrophilic Stress in Cancer: A Minireview
Authors: Sakanyan Vehary
Published: April 2018

Exogenous reactive chemicals can impair cellular homeostasis and are often associated with the development of cancer. Significant progress has been achieved by studying the macromolecular interactions of chemicals that possess various electron-withdrawing groups and the elucidation of the protective responses of cells to chemical interventions. However, the formation of electrophilic species inside the cell and the relationship between oxydative and electrophilic stress remain largely unclear. Derivatives of nitro-benzoxadiazole (also referred as nitro-benzofurazan) are potent producers of hydrogen peroxide and have been used as a model to study the generation of reactive species in cancer cells. This survey highlights the pivotal role of Cu/Zn superoxide dismutase 1 (SOD1) in the production of reactive oxygen and electrophilic species in cells exposed to cell-permeable chemicals. Lipophilic electrophiles rapidly bind to SOD1 and induce stable and functionally active dimers, which produce excess hydrogen peroxide leading to aberrant cell signalling. Moreover, reactive oxygen species and reactive electrophilic species, simultaneously generated by redox reactions, behave as independent entities that attack a variety of proteins. It is postulated that the binding of the electrophilic moiety to multiple proteins leading to impairing different cellular functions may explain unpredictable side effects in patients undergoing chemotherapy with reactive oxygen species (ROS)-inducing drugs. The identification of proteins susceptible to electrophiles at early steps of oxidative and electrophilic stress is a promising way to offer rational strategies for dealing with stress-related malignant tumors.
How Well Do COP22 Attendees Understand Graphs on Climate Change Health Impacts from the Fifth IPCC Assessment Report?
Authors: Fischer Helen , Schütte Stefanie , Depoux Anneliese , Amelung Dorothee , Sauerborn Rainer
Published: April 2018

Graphs are prevalent in the reports of the Intergovernmental Panel on Climate Change (IPCC), often depicting key points and major results. However, the popularity of graphs in the IPCC reports contrasts with a neglect of empirical tests of their understandability. Here we put the understandability of three graphs taken from the Health chapter of the Fifth Assessment Report to an empirical test. We present a pilot study where we evaluate objective understanding (mean accuracy in multiple-choice questions) and subjective understanding (self-assessed confidence in accuracy) in a sample of attendees of the United Nations Climate Change Conference in Marrakesh, 2016 (COP22), and a student sample. Results show a mean objective understanding of M = 0.33 for the COP sample, and M = 0.38 for the student sample. Subjective and objective understanding were unrelated for the COP22 sample, but associated for the student sample. These results suggest that (i) understandability of the IPCC health chapter graphs is insufficient, and that (ii) particularly COP22 attendees lacked insight into which graphs they did, and which they did not understand. Implications for the construction of graphs to communicate health impacts of climate change to decision-makers are discussed.
Analysis of Land Use Change and Expansion of Surface Urban Heat Island in Bogor City by Remote Sensing
Authors: Nurwanda Atik , Honjo Tsuyoshi
Published: April 2018

Bogor as one of the satellite cities of Jakarta Metropolitan experiences rapid population growth and urban development. The urban landscape that is changed by urban development affects the city expansion, the increase of land surface temperature (LST), and the urban heat island (UHI). Objectives of this study are to analyze the city expansion, to analyze the LST characteristic of each land use type, and to examine the correlation between LST change and land use change that is affected by the city expansion. We examined the development of the UHI through the city expansion and the increasing of LST. Landsat 5 TM in 1990, 1997, 2007, and Landsat 8 OLI/TIRS in 2017 were used in this study. For the land used classification, we used Local Climate Zone (LCZ) classification system. The result shows that Bogor has experienced city expansion in the last 27 years. According to the rate of city expansion in the different period, the highest city expansion occurred in 1997–2007 by 8213.7 ha in the analyzed area. In the analysis of relationship between LST and LCZ, there are differences of LSTs among LCZ categories. We also found the area that shows a high LST value expanded broadly towards suburban area with urban development. The temperature differences between urban and suburban were 1.36 °C in 1990, 2.33 °C in 1997, 2.97 °C in 2007, and 2.26 °C in 2017. We defined urban change degree to quantify the land use change, and it is compared with LST change. By the analysis, strong influence of urban expansion on the distribution of surface UHI was observed.
Assessing the Influence of Spatio-Temporal Context for Next Place Prediction using Different Machine Learning Approaches
Authors: Urner Jorim , Bucher Dominik , Yang Jing , Jonietz David
Published: April 2018

For next place prediction, machine learning methods which incorporate contextual data are frequently used. However, previous studies often do not allow deriving generalizable methodological recommendations, since they use different datasets, methods for discretizing space, scales of prediction, prediction algorithms, and context data, and therefore lack comparability. Additionally, the cold start problem for new users is an issue. In this study, we predict next places based on one trajectory dataset but with systematically varying prediction algorithms, methods for space discretization, scales of prediction (based on a novel hierarchical approach), and incorporated context data. This allows to evaluate the relative influence of these factors on the overall prediction accuracy. Moreover, in order to tackle the cold start problem prevalent in recommender and prediction systems, we test the effect of training the predictor on all users instead of each individual one. We find that the prediction accuracy shows a varying dependency on the method of space discretization and the incorporated contextual factors at different spatial scales. Moreover, our user-independent approach reaches a prediction accuracy of around 75%, and is therefore an alternative to existing user-specific models. This research provides valuable insights into the individual and combinatory effects of model parameters and algorithms on the next place prediction accuracy. The results presented in this paper can be used to determine the influence of various contextual factors and to help researchers building more accurate prediction models. It is also a starting point for future work creating a comprehensive framework to guide the building of prediction models.
Adropin Contributes to Anti-Atherosclerosis by Suppressing Monocyte-Endothelial Cell Adhesion and Smooth Muscle Cell Proliferation
Authors: Sato Kengo , Yamashita Tomoyuki , Shirai Remina , Shibata Koichiro , Okano Taisuke , Yamaguchi Maho , Mori Yusaku , Hirano Tsutomu , Watanabe Takuya
Published: April 2018

Adropin, a peptide hormone expressed in liver and brain, is known to improve insulin resistance and endothelial dysfunction. Serum levels of adropin are negatively associated with the severity of coronary artery disease. However, it remains unknown whether adropin could modulate atherogenesis. We assessed the effects of adropin on inflammatory molecule expression and human THP1 monocyte adhesion in human umbilical vein endothelial cells (HUVECs), foam cell formation in THP1 monocyte-derived macrophages, and the migration and proliferation of human aortic smooth muscle cells (HASMCs) in vitro and atherogenesis in Apoe−/− mice in vivo. Adropin was expressed in THP1 monocytes, their derived macrophages, HASMCs, and HUVECs. Adropin suppressed tumor necrosis factor α-induced THP1 monocyte adhesion to HUVECs, which was associated with vascular cell adhesion molecule 1 and intercellular adhesion molecule 1 downregulation in HUVECs. Adropin shifted the phenotype to anti-inflammatory M2 rather than pro-inflammatory M1 via peroxisome proliferator-activated receptor γ upregulation during monocyte differentiation into macrophages. Adropin had no significant effects on oxidized low-density lipoprotein-induced foam cell formation in macrophages. In HASMCs, adropin suppressed the migration and proliferation without inducing apoptosis via ERK1/2 and Bax downregulation and phosphoinositide 3-kinase/Akt/Bcl2 upregulation. Chronic administration of adropin to Apoe−/− mice attenuated the development of atherosclerotic lesions in the aorta, with reduced the intra-plaque monocyte/macrophage infiltration and smooth muscle cell content. Thus, adropin could serve as a novel therapeutic target in atherosclerosis and related diseases.