bluuebunny/crossref_metadata_2025 huggingface dataset:
Behaviors of Oxide Film during Semisolid Brazing of SiCp/6063Al Composite Materials
Authors: Xiao Jing , Li Shun , Bai Shuxin , Yan Jiuchun , Xiong Degan
Published: September 2018

The semisolid brazing of SiCp/6063Al under an applied pressure using Zn‐Al‐Cu filler metal was investigated. The samples to be joined were heated from 380°C to 382°C, 386°C, 392°C, and 410°C under a constant pressure of 10 MPa, respectively. Effects of the temperature on microstructural evolution and deformation behavior of the filler metal, interfacial structure, and shear strength of the bonded joint were discussed, and the disruption behavior of the surface oxide film was studied. The results show that, after heating, the solid grains of the filler metal transform into a globular structure surrounded by liquid. The degree of sphericity and the liquid fraction tend to improve with increasing temperature. During the heating process, the deformation of the filler metal is first accomplished by plastic deformation of solid grains and then by intergrain sliding and liquid flow. The surface oxides are broken and stripped by a cocontribution of compressive and shear stress which is caused by depressing and sliding of solid grains along the composites. It is found that the heating of 380°C to 392°C under pressure is the optimum condition to disrupt the surface oxide films and obtain sound bonds. The mechanical test results show that the maximum shear strength of the bond joints is as high as 105 MPa, reaching 78% that of the parent materials.
Finding Missing Links in Complex Networks: A Multiple‐Attribute Decision‐Making Method
Authors: Li Longjie , Bai Shenshen , Leng Mingwei , Wang Lu , Chen Xiaoyun
Published: September 2018

Link prediction, which aims to forecast potential or missing links in a complex network based on currently observed information, has drawn growing attention from researchers. To date, a host of similarity‐based methods have been put forward. Usually, one method harbors the idea that one similarity measure is applicable to various networks, and thus has performance fluctuation on different networks. In this paper, we propose a novel method to solve this issue by regarding link prediction as a multiple‐attribute decision‐making (MADM) problem. In the proposed method, we consider RA, LP, and CAR indices as the multiattribute for node pairs. The technique for order performance by similarity to ideal solution (TOPSIS) is adopted to aggregate the multiattribute and rank node pairs. The proposed method is not limited to only one similarity measure, but takes separate measures into account, since different networks may have different topological structures. Experimental results on 10 real‐world networks manifest that the proposed method is superior in comparison to state‐of‐the‐art methods.
Assessment of Adequate Margin to Liquefaction for Nuclear Power Plants
Authors: Katona Tamás János
Published: September 2018

Design of nuclear power plant shall provide an adequate margin to protect items ultimately necessary to prevent an early large radioactive release in the case of earthquakes exceeding those considered in the design. An essential question is how large the margin should be to be accepted as adequate. In the practice, depending on the country regulation, a plant margin of at least 1.4 or 1.67 times the design basis peak ground acceleration is required to be demonstrated. The catastrophe at the Fukushima Daiichi Nuclear Power Plant revealed the fundamental experience that the plants designed in compliance with nuclear standards can survive the effects of the vibratory ground motion due to disastrous earthquake but may fail due to effects of phenomena accompanying or generated by the earthquakes. Liquefaction is one of those secondary effects of beyond-design basis earthquakes that should be investigated for NPPs at soil sites. However, the question has not been investigated up to now, whether a “margin earthquake”, vibratory effects of which the plant can withstand thanks to design margin, will not induce liquefaction at soil sites and will not result in loss of safety functions. In the paper, a procedure is proposed for calculation of the probability and margin to liquefaction. Use of the procedure is demonstrated on a case study with realistic site-plant parameters. Criteria for probability for screening and acceptable probabilistic margin to liquefaction are proposed. The possible building settlement due to margin earthquake is also assessed.
Determination of Curdlan Oligosaccharides with High-Performance Anion Exchange Chromatography with Pulsed Amperometric Detection
Authors: Cao Lidong , Tian Huifang , Wu Miaomiao , Zhang Hongjun , Zhou Puguo , Huang Qiliang
Published: September 2018

The increasing interest of curdlan oligosaccharides (COS) in medicine and plant protection fields implies a necessity to identify and quantify this product. In the present study, an efficient and sensitive analytical method based on high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) was established for the simultaneous separation and determination of D-glucose and ß-1,3-linked COS ranging from (COS)2 to (COS)6 within 20 min. Detection limits were 0.01 to 0.03 mg/L. The optimized assay was performed on a CarboPac-PA100 analytical column (4 mm × 250 mm) using isocratic elution with water−0.2 M sodium hydroxide−0.5 M sodium acetate mixture (50 : 30 : 20, v/v/v) as the mobile phase at a flow rate of 0.8 mL/min. Regression equations indicated a good linear relationship (R2 = 0.9992–1.0000, n = 6) within the test ranges. Quality parameters including precision and accuracy were fully validated and found to be satisfactory. More important, the regression of natural logarithm values of retention times (log10 RT) versus the degree polymerization (DP), as well as the slope coefficient of each COS’s linear equation versus the corresponding DP, fitted a linear relationship well. These inherent linear relationships could provide valuable information to tentatively identify and quantify the COS even with the DP more than 6 without authentic standard. Furthermore, when the log10 RT was plotted against log10 flow rate for each COS, a perfect linear relationship was also observed.
A Study of Hydromagnetic Longitudinal Rough Circular Step Bearing
Authors: Adeshara Jatinkumar V. , Prajapati M. B. , Deheri G. M. , Patel R. M.
Published: September 2018

This article discusses the effect of longitudinal roughness on the performance of hydromagnetic squeeze film in circular step bearing. To characterize the random roughness of the bearing surfaces the stochastic model of Christensen and Tonder has been employed. The stochastically averaged Reynolds’ type equation is solved using suitable boundary conditions to obtain the pressure distribution and then the load bearing capacity is computed. The results are presented in graphical form. The graphical results presented here establish that the hydromagnetic lubrication offers significant help to the longitudinal roughness pattern to enhance the performance of the bearing system. Of course, conductivities of the plates, standard deviation, and the supply pressure contribute towards reducing the negative effect induced by variance (+ve) and skewness (+ve).
Green Synthesis of Iron Nanoparticles: Application on the Removal of Petroleum Oil from Contaminated Water and Soils
Authors: Murgueitio Erika , Cumbal Luis , Abril Mayra , Izquierdo Andrés , Debut Alexis , Tinoco Oscar
Published: September 2018

Iron nanoparticles were produced using the extract of mortiño berry (Vaccinium floribundum) (vZVI) as reducing and stabilizer agent. Fresh nanoparticles were characterized using TEM, XRD, and FTIR techniques, while laboratory experiments were conducted to assess the removal of total petroleum hydrocarbons (TPHs) from water and soil after treatment with synthesized nanoscale iron particles. Nanoparticles as produced were spherical in the range of 5–10 nm. After treatment with vZVI nanoparticles, water contaminated with two concentrations of TPHs (9.32 mg/L and 94.20 mg/L) showed removals of 85.94% and 88.34%, respectively, whereas a contaminated soil with a TPHs concentration of 5000 mg/kg treated during 32 h with nanoparticles reached a removal of 81.90%. Results indicate that the addition of vZVI nanoparticles produced strong reducing conditions, which accelerate removal of TPHs and suggest that these nanoparticles might be a promising technology to clean up TPHs contaminated water and soils.
Evaluation of Routine Microscopy Performance for Malaria Diagnosis at Three Different Health Centers in Brazzaville, Republic of Congo
Authors: Mayengue Pembe Issamou , Kouhounina Batsimba Dezi , Dossou-Yovo Louis Régis , Niama Roch Fabien , Macosso Lucette , Pembet Singana Brice , Louzolo Igor , Bongolo Loukabou Nadia Claricelle , Sekangue Obili Géril , Kobawila Simon Charles , Parra Henri Joseph
Published: September 2018

Background. In Republic of Congo, malaria diagnosis still widely relies on microscopy. We aimed to evaluate the performance of routine microscopy for malaria diagnosis at three different health centers in Brazzaville. Methods. A total of 259, 416, and 131 patients with clinical signs of uncomplicated malaria were enrolled at the Hôpital de Mfilou, Centre de Santé Intégré “Maman Mboualé,” and Laboratoire National de Santé Publique, respectively. Two thick blood smears were prepared for each patient, the first being examined by routine microscopists and the second by expert. Results. At the Hôpital de Mfilou, sensitivity was 62.1% and specificity was 67.3%. Positive and negative predictive values were 55.6% and 72.9%, respectively. At the Centre de Santé Intégré “Maman Mboualé,” sensitivity was 94.2% and specificity was 33.6%. Positive and negative predictive values were 50% and 89.1%, respectively. At the Laboratoire National de Santé Publique, sensitivity and specificity were high with 91.7% and 94.9%, respectively. Positive and negative predictive values were 64.7% and 99.1%, respectively. Conclusion. The performance of routine malaria microscopy in Brazzaville remains inaccurate with large variations among different health centers. Therefore, repeated training including supervision and evaluation would improve routine malaria diagnosis for better management of malaria in Brazzaville, the Republic of Congo.
Properties of a Prototype Corium of Nuclear Reactor
Authors: Skakov Mazhyn K. , Mukhamedov Nurzhan Ye. , Deryavko Ilya I. , Batyrbekov Erlan G.
Published: September 2018

The paper studies structure, phase composition, and thermophysical properties (TPP) (specific heat capacity, thermal diffusivity, and heat conductivity) of a prototype corium of a fast nuclear reactor (melt of core materials of nuclear reactor produced under out-of-pile conditions). The obtained data will be used to get more accurate understanding of main regularities of actual interaction of core materials of a nuclear reactor under a severe accident.
Testing of Weakly Weathered Granites of Different Porosities Using a Split Hopkinson Pressure Bar Technique
Authors: Yan Lei , Liu Liansheng , Zhang Shenghui , Lan Depei , Liu Jiangchao
Published: September 2018

Nuclear magnetic resonance (NMR) and damage impact testing, using a split Hopkinson pressure bar (SHPB) technique, were conducted on weakly weathered granites of different porosities. Based on this, this study determined and analysed the pore structure and distribution, propagation characteristics of stress waves, changes in initial tangent modulus, and energy dissipation in weakly weathered granites of different porosities. The research demonstrated that the nature of the internal porosity of weakly weathered granites changed with total porosity. Pore structure significantly influenced the amplitude of reflected waves and distortion of transmitted waves. Under constant‐damage impact loads, the initial tangent modulus decreased with increasing porosity, whereas the stress‐strain curves, after reaching the peak stress, had similar shapes. Peak stress and average strain rate showed a strong power‐law correlation with porosity, and peak stress decreased in a power‐law correlation with the increase of average strain rate. In other words, the difference in average strain resulted from different porosities when the incident energy was same, and the average strain was negatively correlated with porosity. Under damaging impact, the energy absorbed per unit volume decreased with increasing porosity. The research results reveal dynamic characteristics of natural porous rocks under damage impacts, which provide a reference for studying damage effects of porous rocks under the effects of stress waves.
Tests of Inclined Concrete‐Filled Steel Tubular Stub Columns under Vertical Cyclic Loading
Authors: Hansapinyo Chayanon , Buachart Chinnapat , Chaimahawan Preeda
Published: September 2018

This paper presents an experimental study on the cyclic behavior of fifteen concrete‐filled steel tubular columns subjected to vertical cyclic loading. All test samples’ cross‐sectional area is 75 × 75 mm2 square, and they are 500 mm long. The main variables in the test are the thickness of the steel tube (1.8 and 3.0 mm with the width‐to‐thickness ratios (b/t) of 41.7 and 25), the strength of the infilled concrete (no‐fill, 23 MPa, and 42 MPa), and the inclined angle (0, 4, and 9 degrees). The results show that all samples failed due to local buckling in compression followed by tearing of the steel tube in tension. The inclination angles of 4 and 9 degrees decreased the vertical compressive capacity of the 1.8 mm vertical hollowed steel column by 34 and 39 percent, respectively. However, the infilled concrete and thicker tube (3.0 mm) could substantially reduce the adverse effect of the inclination angle. The compressive ductility of the hollowed column with the thinner tube was significantly enhanced by the infilled concrete as well.
Characteristics, Outcomes, and Cost Patterns of High-Cost Patients in the Intensive Care Unit
Authors: Reardon Peter M. , Fernando Shannon M. , Van Katwyk Sasha , Thavorn Kednapa , Kobewka Daniel , Tanuseputro Peter , Rosenberg Erin , Wan Cynthia , Vanderspank-Wright Brandi , Kubelik Dalibor , Devlin Rose Anne , Klinger Christopher , Kyeremanteng Kwadwo
Published: September 2018

Background. ICU care is costly, and there is a large variation in cost among patients.Methods. This is an observational study conducted at two ICUs in an academic centre. We compared the demographics, clinical data, and outcomes of the highest decile of patients by total costs, to the rest of the population.Results. A total of 7,849 patients were included. The high-cost group had a longer median ICU length of stay (26 versus 4 days,P<0.001) and amounted to 49% of total costs. In-hospital mortality was lower in the high-cost group (21.1% versus 28.4%,P<0.001). Fewer high-cost patients were discharged home (23.9% versus 45.2%,P<0.001), and a large proportion were transferred to long-term care (35.1% versus 12.1%,P<0.001). Patients with younger age or a diagnosis of subarachnoid hemorrhage, acute respiratory failure, or complications of procedures were more likely to be high cost.Conclusions. High-cost users utilized half of the total costs. While cost is associated with LOS, other drivers include younger age or admission for respiratory failure, subarachnoid hemorrhage, or after a procedural complication. Cost-reduction interventions should incorporate strategies to optimize critical care use among these patients.
Dynamics of Nonlinear Primary Oscillator with Nonlinear Energy Sink under Harmonic Excitation: Effects of Nonlinear Stiffness
Authors: Sun Min , Chen Jianen
Published: September 2018

The dynamics of a system consisting of a nonlinear primary oscillator, subjected to a harmonic external force, and a nonlinear energy sink (NES) are investigated. The analytical solutions for the steady-state responses are obtained by the complexification-averaging method and the analytical model is confirmed by numerical simulations. The results indicate that the introduction of the NES can effectively suppress the vibrations of the primary oscillator. However, as the excitation amplitude increased, the NES may lose its efficiency within certain frequency range due to the appearance of the high response branches. Following the results analysis, it is concluded that this failure can be eliminated by reducing the nonlinear stiffness of the NES properly. The effects of nonlinear stiffness of the primary oscillator on the corresponding responses are also studied. The increase in this nonlinear stiffness can reduce the response amplitude and alter the frequency band where the high branches exist.
Surface Morphology of Structural Plane and Effects of the Shear Strength Parameters
Authors: He Dongliang , Yang Weijun , Cheng Yanhui
Published: September 2018

The surface morphology of a discontinuous structural plane in a natural rock mass is irregular. In studies on the shear strength of discontinuous structural planes, Barton introduced the joint roughness coefficient (JRC) to describe and calibrate the morphological characteristics of a rough structural plane. To describe Barton’s typical rough profile model, researchers commonly conduct a comparison based on a standard curve. This approach does not guarantee graphic precision. With subjective comparison reference drawing, the size and angle of a structural plane cannot be quantitatively controlled, and small bumps cannot be described. When the influence of the roughness coefficient of a rock surface is discussed, errors are caused by comparing Barton’s typical roughness profile model and a general structural surface model. This paper proposed a new method to simulate Barton’s typical structural surface. A numerical model of a complex structural plane is built automatically. The effects of cohesion and internal friction angle on the shear strength of the structural plane are discussed by changing the value of the shear strength parameters.
Process of Air Ingress during a Depressurization Accident of GTHTR300
Authors: Shiga Tomoya , Tanaka Yudai , Takada Tetsuaki
Published: September 2018

A depressurization accident is the design-basis accidents of a gas turbine high temperature reactor, GTHTR300, which is JAEA’s design and one of the Very-High-Temperature Reactors (VHTR). When a primary pipe rupture accident occurs, air is expected to enter the reactor core from the breach and oxidize in-core graphite structures. Therefore, it is important to know a mixing process of different kinds of gases in the stable and unstable density stratified fluid layer. In order to predict or analyze the air ingress phenomena during the depressurization accident, we have conducted an experiment to obtain the mixing process of two component gases and the characteristics of natural circulation. The experimental apparatus consists of a storage tank and a reverse U-shaped vertical rectangular passage. One side wall of the high temperature side vertical passage is heated and the other side wall is cooled. The other experimental apparatus consists of a cylindrical double coaxial vessel and a horizontal double coaxial pipe. The outside of the double coaxial vessel is cooled and the inside is heated. The results obtained in this study are as follows. When the primary pipe is connected at the bottom of the reactor pressure vessel, onset time of natural circulation of air is affected by not only molecular diffusion but also localized natural convection. When the wall temperature difference is large, onset time of natural circulation of air is strongly affected by natural convection rather than molecular diffusion. When the primary pipe is connected at the side of the reactor pressure vessel, air will enter the bottom space in the reactor pressure vessel by counter-current flow at the coaxial double pipe break part immediately. Afterward, air will enter the reactor core by localized natural convection and molecular diffusion.
Decade-Long Changes in Disparity and Distribution of Transit Opportunity in Shenzhen China: A Transportation Equity Perspective
Authors: Zhou Qingfeng , Dai Donghui , Wang Yaowu , Fan Jianshuang
Published: September 2018

Efficiency and equity have always been the two points of focus of transport projects. Compared with efficiency, equity is easily overlooked in the evaluation of transport projects. Many studies emphasize that defining and operationalizing costs and benefits and the distributive principle are critical parts in the assessment of transportation equity. However, the scope and time frame of the assessment target are also critical. In this paper, we took China’s fastest urbanizing city, Shenzhen, as a case study to assess transport equity by comparing accessibility among groups. First, the public transport system was divided into bus and subway, and the residents were divided into two groups: urban village and nonurban village. Second, we adopted an enhanced potential opportunity model to measure residents’ bus and subway accessibility and summarized them as transit opportunity. Third, we used the Dagum Gini coefficient decomposition and kernel density estimation method to explore the fair distribution of transit opportunity among groups and districts from 2011 to 2020. Decade-long changes in disparity and distribution of transit opportunity gave us a clear picture. On the one hand, the development of Shenzhen public transport system had a positive effect. All populations are benefiting, and their accessibility is increasing. On the other hand, it also had a negative effect to exacerbate inequality between populations. For the absolute value of the opportunity, Shenzhen’s urban village populations do have fewer transportation opportunities than nonurban villages, and this gap between them will be wider more and more. The public transport system is more inclined to improve the population with high initial opportunity and make them higher. The results illustrated the importance of examining transportation equity over an extended period and could provide information on urban development strategies.
Prevalence of Stress and Associated Factors among Regular Students at Debre Birhan Governmental and Nongovernmental Health Science Colleges North Showa Zone, Amhara Region, Ethiopia 2016
Authors: Abebe Ayele Mamo , Kebede Yilma Girma , Mengistu Fikir
Published: September 2018

Background. Stress is very common among medical students across the globe with the prevalence of 80%. In Ethiopia, the prevalence is 47.7% among college students. Unless it is managed early, it leads to deterioration of academic performance and overall dissatisfaction with life and different serious health problems including anxiety, depression, and suicide. The objective of this study is to assess the prevalence of academic related stress among Debre Birhan governmental and nongovernmental health science college regular students 2015/16. Method. A cross-sectional study was conducted on a sample of 422 health science students selected by stratified proportional random sampling at Debre Birhan governmental and nongovernmental health science colleges in North Shewa zone, Amhara region, Ethiopia in 2016. Data was collected using the Depression Anxiety Stress Scaling (DASS-21). The level of significance of association for multivariable was determined at P value <0.05. Result. Prevalence of stress among Debre Birhan governmental and nongovernmental health science college regular students is 4.1%. There is a significant association between stress and sex AOR = 8.525 (1.023, 71.077), fear of examination AOR = 5.096 (1.183, 21.96), living in uncomfortable environment AOR = 14.86 (3.84, 57.515), and perceived present illness AOR = .030 (0.003, 0.286). Depression and anxiety were also seen among 19.7% and 23.6%, respectively. Conclusion. According to this study, the prevalence of stress among governmental and nongovernmental health science college regular students is not high. However, depression and anxiety were found to be higher than stress and they need immediate management plan. Colleges had better prepared simple screening tool and support students to prevent stress before they cause severe mental health problems.
Dynamics of Lotka-Volterra Competition Systems with Fokker-Planck Diffusion
Authors: Chung Jaywan , Kwon Ohsang
Published: September 2018

We consider competition systems of two species which have different dispersal strategies and interspecific competitive strengths. One of the dispersal strategies is random dispersal and the other is a Fokker-Planck diffusion whose motility is piecewise constant and jumps up when the resource is not enough. In this paper, first we show the Fokker-Planck diffusion allows ideal free distribution. Next we show the linear stability of semitrivial steady states is determined exactly by a threshold on the interspecific competitive strengths. Some conditions for coexistence and global asymptotic stability are also provided.
Hermitian Operators and Isometries on Banach Algebras of Continuous Maps with Values in Unital Commutative C⁎-Algebras
Authors: Hatori Osamu
Published: September 2018

We study isometries on algebras of the Lipschitz maps and the continuously differentiable maps with the values in a commutative unital C⁎-algebra. A precise proof of a theorem of Jarosz concerning isometries on spaces of continuous functions is exhibited.
Fault Diagnosis of Bearing by Utilizing LWT‐SPSR‐SVD‐Based RVM with Binary Gravitational Search Algorithm
Authors: Fei Sheng-wei
Published: September 2018

The fault diagnosis method of bearing based on lifting wavelet transform (LWT)‐self‐adaptive phase space reconstruction (SPSR)‐singular value decomposition (SVD)‐based relevance vector machine (RVM) with binary gravitational search algorithm (BGSA) is presented in this study, among which LWT‐SPSR‐SVD (LSS) is presented for feature extraction of the bearing vibration signal, the dynamic characteristics of lifting wavelet coefficients′ (LWCs′) reconstructed signals of the bearing vibration signal can be reflected by SPSR for LWCs′ reconstructed signals of the bearing vibration signal, and BGSA is used to select the embedding space dimension and time delay of phase space reconstruction (PSR) and kernel parameter of RVM. In order to show the superiority of LWT‐SPSR‐SVD‐based RVM with BGSA (LSS‐BGSA‐RVM), the traditional RVM trained by the training samples with the features based on LWT‐SVD (LS‐RVM) is used to compare with the proposed LSS‐BGSA‐RVM method. The experimental result demonstrates that compared with LS‐RVM, LSS‐BGSA‐RVM can achieve the higher diagnosis accuracy for bearing.
A Study of Ordered Ag-Groupoids in terms of Semilattices via Smallest (Fuzzy) Ideals
Authors: Amjid Venus , Yousafzai Faisal , Hila Kostaq
Published: September 2018

An ordered AG-groupoid can be referred to as an ordered left almost semigroup, as the main difference between an ordered semigroup and an ordered AG-groupoid is the switching of an associative law. In this paper, we define the smallest one-sided ideals in an ordered AG-groupoid and use them to characterize a strongly regular class of a unitary ordered AG-groupoid along with its semilattices and fuzzy one-sided ideals. We also introduce the concept of an orderedAG⁎⁎⁎-groupoid and investigate its structural properties by using the generated ideals and fuzzy one-sided ideals. These concepts will verify the existing characterizations and will help in achieving more generalized results in future works.
Comparative Glycopeptide Analysis for Protein Glycosylation by Liquid Chromatography and Tandem Mass Spectrometry: Variation in Glycosylation Patterns of Site-Directed Mutagenized Glycoprotein
Authors: Hahm Young Hye , Hahm Sung Ho , Jo Hyoun Young , Ahn Yeong Hee
Published: September 2018

Glycosylation is one of the most important posttranslational modifications for proteins, including therapeutic antibodies, and greatly influences protein physiochemical properties. In this study, glycopeptide mapping of a reference and biosimilar recombinant antibodies (rAbs) was performed using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) and an automated Glycoproteome Analyzer (GPA) algorithm. The tandem mass analyses for the reference and biosimilar samples indicate that this approach proves to be highly efficient in reproducing consistent analytical results and discovering the implications of different rAb production methods on glycosylation patterns. Furthermore, the comparative analysis of a mutagenized rAb glycoprotein proved that a single amino acid mutation in the Fc portion of the antibody molecule caused increased variations in glycosylation patterns. These variations were also detected by the mass spectrometry method efficiently. This mapping method, focusing on precise glycopeptide identification and comparison for the identified glycoforms, can be useful in differentiating aberrant glycosylation in biosimilar rAb products.
Critical Length and Collapse of Interlayer in Rock Salt Natural Gas Storage
Authors: Wang Yingjie , Liu Jianjun
Published: September 2018

The existence of an interlayer has a significant effect on the stability of a rock salt gas storage cavity; therefore, an uncontrollable collapse of the interlayer would cause a series of issues. In this study, three types of mechanical instability criteria are comprehensively calculated. The limit radius of the interlayer is computed under different criteria, and the collapse radius of the interlayer is obtained by comparison. The calculation results of the mathematical model are highly accurate with respect to actual engineering logging data, in general with over 90% of accuracy. It is demonstrated that, besides the physical and mechanical characteristics of the sandwich, the location of the interlayer in the cavity and concentration of the brine also have an important effect on the collapse of the interlayer. The brine at the bottom of the cavity is nearly saturated. Therefore, an interlayer at this location does not easily collapse. The mathematical model established in this study is used in the seismic design and prediction of interlayer collapse during the construction of salt‐cavern gas storage facilities in China.
Prediction of Pollutant Emissions from Bluff-Body Stabilised Nonpremixed Flames
Authors: Munteanu Nelu , Amzaini Shokri M.
Published: September 2018

Construction of a stable flame is one of the critical design requirements in developing practical combustion systems. Flames stabilised by a bluff-body are extensively used in certain types of combustors. The design promotes mixing of cold reactants and hot products on the flame surface to improve the flame stability. In this study, bluff-body stabilised methane-hydrogen flames are computed using the steady laminar flamelet combustion method in conjunction with the Reynolds-averaged Navier-Stokes (RANS) approach. These flames are known as Sandia jet flames and have different jet mean velocities. The turbulence is modelled using the standard k-ϵ model and the chemical kinetics are modelled using the GRI-mechanism with 325 chemical reactions and 53 species. The computed mean reactive scalars of interest are compared with the experimental measurements at different axial locations in the flame. The computed values are in reasonably good agreement with the experimental data. Although some underpredictions are observed mainly for NO and CO at downstream locations in the flame, these results are consistent with earlier reported studies using more complex combustion models. The reason for these discrepancies is that the flamelet model is not adequate to capture the finite-rate chemistry effects and shear turbulence specifically, for species with a slow time scale such as nitrogen oxides.
The Sources of Reactive Oxygen Species and Its Possible Role in the Pathogenesis of Parkinson’s Disease
Authors: Weng Minrui , Xie Xiaoji , Liu Chao , Lim Kah-Leong , Zhang Cheng-wu , Li Lin
Published: September 2018

Parkinson’s disease (PD) is the second most common neurodegenerative disorder characterized by progressive loss of dopaminergic neurons in the substantia nigra. The precise mechanism underlying pathogenesis of PD is not fully understood, but it has been widely accepted that excessive reactive oxygen species (ROS) are the key mediator of PD pathogenesis. The causative factors of PD such as gene mutation, neuroinflammation, and iron accumulation all could induce ROS generation, and the later would mediate the dopaminergic neuron death by causing oxidation protein, lipids, and other macromolecules in the cells. Obviously, it is of mechanistic and therapeutic significance to understand where ROS are derived and how ROS induce dopaminergic neuron damage. In the present review, we try to summarize and discuss the main source of ROS in PD and the key pathways through which ROS mediate DA neuron death.
An Investigation into Tetrodotoxin (TTX) Levels Associated with the Red Dorsal Spots in Eastern Newt (Notophthalmus viridescens) Efts and Adults
Authors: Spicer Mackenzie M. , Stokes Amber N. , Chapman Trevor L. , Brodie Edmund D. , Brodie Edmund D. , Gall Brian G.
Published: September 2018

We investigated the concentration of tetrodotoxin (TTX) in sections of skin containing and lacking red dorsal spots in both Eastern newt (Notophthalmus viridescens) efts and adults. Several other species, such as Pleurodeles waltl and Echinotriton andersoni, have granular glands concentrated in brightly pigmented regions on the dorsum, and thus we hypothesized that the red dorsal spots of Eastern newts may also possess higher levels of TTX than the surrounding skin. We found no difference between the concentrations of TTX in the red spots as compared to neighboring skin lacking these spots in either efts or adults. However, efts with more red dorsal spots had elevated TTX levels relative to efts with fewer spots.
Modeling and Simulation Study of Two-Phase Collaborative Behaviors Oriented to Open Source Design Process
Authors: Zhang Shuo , Li Yingzi
Published: September 2018

Open source design (OSD) is an emerging cluster design mode based on Internet, and it takes full advantage of knowledge, technology, and resources among designers to promote product development. In this mode, designers’ behaviors of collaboration have important influence on product development process. In this paper, firstly collaboration flow including two types of collaboration relations between designers in open source design is depicted. Secondly, two-phase collaborative behavior model including partner selection and response is built by means of utility functions. At last, simulation experiment including 4 scenarios is designed based on open source project of mobile phone and conducted by multiagent simulation, and contrastive analysis is carried out to study collaboration behaviors’ impact on open source design process. The results show that the two-phase collaborative behavior model elaborately describes structure evolution of Open Source Community (OSC) as well as designers’ collaboration behaviors and that different ways of partner selection behaviors have significant impact on the evolution of OSD process as well as OSC structure. Furthermore, the results suggest that designers should better consider more the factor of matching degree between designers but less collaboration record.
Cell Disruption of Chaetoceros calcitrans by Microwave and Ultrasound in Lipid Extraction
Authors: Nogueira Daniela Almeida , da Silveira Juliane Machado , Vidal Évelin Mendes , Ribeiro Natália Torres , Veiga Burkert Carlos André
Published: September 2018

Downstream processing, such as cell disruption and extraction, constitutes a key step in microalgal-based industrial bioprocesses, mainly due to high costs and environmental impact. In this context, extraction technologies need to be improved, including the use of nonconventional cell disruption techniques suitable for scale-up, such as microwave and ultrasound. Therefore, this study aimed at investigating the effects of different methods of cell disruption (microwave and ultrasound) on lipid extraction from biomass of the diatom Chaetoceros calcitrans cultured in mixotrophic conditions in a medium with natural sea water and residual glycerol, with different treatment times. Both techniques applied to the biomass were efficient; that is, the results were 24.6 ± 1.3% lipids (ultrasound for 5 min) and 24.2 ± 0.9% lipids (microwave for 40 s), with no significant differences between them (p≥0.05). Likewise, there was no significant difference regarding the chemical disruption with hydrochloric acid 2 M as control (24.2 ± 1.0%). The ultrasound method consumed less energy than the microwave method. Both cell disruption methods applied to the biomass resulted in changes in the fatty acid profiles, that is, percentages of saturated fatty acids increased from 7.7% (control) to 16.6% (microwave) and 15.5% (ultrasound), whereas polyunsaturated ones increased from 12.8% (control) to 22.8% (microwave) and 21.8% (ultrasound). Concerning monounsaturated fatty acids, percentages decreased from 79.5% (control) to 60.6% (microwave) and 62.7% (ultrasound).
QoE‐Aware Scheduling Algorithm for Adaptive HTTP Video Delivery in Wireless Networks
Authors: Rodrigues Frederico , Sousa Ivo , Queluz Maria Paula , Rodrigues António
Published: September 2018

In the last years, the video content consumed by mobile users has increased exponentially. Since mobile network capacity cannot be increased as fast as required, it is crucial to develop intelligent schedulers that allocate radio resources very efficiently and are able to provide a high Quality of Experience (QoE) to most of the users. This paper proposes a new and effective scheduling solution—the Maximum Buffer Filling (MBF) algorithm—which aims to increase the number of satisfied users in video streaming services provided by wireless networks. The MBF algorithm uses the current buffer level at the client side and the radio channel conditions, which are reported to the network by the client, as well as the bitrate of the requested video segment. The proposed scheduling strategy can also fulfill different satisfaction criteria, since it can be tuned to maximize the numbers of users with high QoE levels or to minimize the number of users with low QoE levels. A simulation framework was developed, considering a Long Term Evolution (LTE) scenario, in order to assess the performance of the proposed scheduling scheme and to compare it with other well‐known scheduling solutions. The results show the superior performance achieved by the proposed technique, in terms of the number of satisfied and unsatisfied users.
Ultra-Short-Term Prediction of Wind Power Based on Fuzzy Clustering and RBF Neural Network
Authors: Hui Huang , Rong Jia , Songkai Wang
Published: September 2018

High-precision wind power forecast can reduce the volatility and intermittency of wind power output, which is conducive to the stable operation of the power system and improves the system's effective capacity for large-scale wind power consumption. In the wind farm, the wind turbines are located in different space locations, and its output characteristics are also affected by wind direction, wake effect, and operation conditions. Based on this, two-step ultra-short-term forecast model was proposed. Firstly, fuzzy C-means clustering (FCM) theory was used to cluster the units according to the out characteristics of wind turbines. Secondly, a prediction model of RBF neural network is established for the classification clusters, respectively, and the ultra-short-term power forecast is performed for each unit. Finally, the above results are compared with the RBF single prediction model established by unclassified g wind turbines. A case study of a wind farm in northern China is carried out. The results show that the proposed method can effectively improve the prediction accuracy of wind power and prove the effectiveness of the method.
John Bell and the Great Enterprise
Authors: Sudbery Anthony
Published: September 2018

I outline Bell's vision of the "great enterprise" of science, and his view that conventional teachings about quantum mechanics constituted a betrayal of this enterprise. I describe a proposal of his to put the theory on a more satisfactory footing, and review the subsequent uses that have been made of one element of this proposal, namely Bell's transition probabilities regarded as fundamental physical processes.Quanta 2018; 7: 68–73.
Good person, good citizen? The discourses that Chinese youth invoke to make civic and moral meaning
Authors: Xiang Xin , Zhao Xu , Zhang Siwen , Lee Ashley , Li Yiyu , Haste Helen , Liu Zhi , Cotnam-Kappel Megan
Published: September 2018

In a time of transition, China is formulating principles for moral and civic responsibility and action that will serve the new goals for an expanding world power. How do young Chinese people define the ‘good person’ and ‘good citizen’, and the qualities to which they should aspire, in this changing climate? How do these mesh with the public messages and the historical traditions from which they derive? Using discourse analysis we report data from 8th and 11th grade students in Shanghai and Nantong that reveal four discourses around civic and moral responsibilities, norms and goals. Discourse analysis enables us to identify the underlying explanatory narratives that attribute causality and consequence, position people and institutions, imply judgements and values, and prescribe acceptable or expected actions. The four discourses are (1) Obeying Rules and Laws; (2) Building and Maintaining Relationships; (3) Striving towards Moral Perfection and High ‘Quality’; and (4) Loving One’s Country and Contributing to Society.
A new wild: Reimagining the potential of indigenous biodiversity in Aotearoa, New Zealand
Authors: Abbott Mick , Blackburne Kate , Boyle Cameron , Lee Woody , Pickett Tenille
Published: September 2018

This article presents ways to rethink current approaches to protected areas in New Zealand, which have been dominated by problematic colonial ideas that uniformly construct such places as separate from people and as reminiscent of a pre-human past. This has resulted in the strict separation of productive landscapes from protected landscapes in Aotearoa, New Zealand. A re-evaluation of the idea of allocating further lands that have high endemic biodiversity values solely for protection is considered in light of the country’s public conservation lands reaching 33 per cent of the country’s total land area and still continuing to grow. Using a design-directed research approach we put forward seven alternatives to imagining protected areas that act as speculative futures from which to reimagine and expand the potential of New Zealand’s indigenous biodiversity beyond solely preservation-focused approaches that have been based on a fortress conservation model. These futures are not prescriptive but opportunities to extend the value that New Zealand’s indigenous biodiversity might have, and consider its capacity to foster deep connections between people and place, in ways in which both endemic biodiversity and people thrive.
Art therapy training for relief workers to provide support and sustainability
Authors: Bardot Heidi
Published: September 2018

This article looks at training mental health and relief workers, interacting directly with refugee populations, to utilize art therapy techniques in response to trauma. The workshop trainings served two purposes: to educate front-line workers in utilizing techniques to expand the breadth of work and provide sustainable art therapy services, and to provide support for the trainees from vicarious trauma and burnout from the work. The second aspect of the workshop concentrated on group exercises to provide team cohesion and more internally focused techniques for self-care. Specific techniques were introduced, and cultural and site-specific modifications were explored.
The development of well-being and supervision programmes for caregivers in post conflict Cambodia: A creative response to the need for long term sustainability
Authors: Herbert Carrie
Published: September 2018

This article will describe a creative arts therapy action research that engages organizations in a collaborative process in the development of effective responses to staff care and organizational well-being in the context of post conflict humanitarian work in Cambodia. Creative Arts Therapy techniques used in supervision, de-briefing and assessment processes were developed to support staff care well-being practice and policy creation in Cambodia with non-governmental organizations. This model revealed an acute need for effective staff care and well-being programmes across agencies and demonstrated a subsequent reduction in the levels of work-related stress and vicarious trauma. The model proposes the development of national guidelines for policy and practice alongside the building of capacity in national staff for ongoing evolution and implementation. It is further recommended that such developments need adequate time, support and resource investment for integration into a policy, structure and programming of an organization.
Manipulation of rumen fermentation by bioindustrial products of cashew nut shell (Anacardiumoccidentale) to reduce methane and enhance other products
Authors: Saenab Andi , KG Wiryawan , Y Retnani , Wina Elizabeth
Published: September 2018

One of the strategies to reduce methane produced by ruminants is by the application of feed additive from plant materials. One of the potential plants is cashew plant especially its shell. The cashew nut shell can be processed to become 3 bioindustrial products; ie biofat, biochar, biosmoke. The aim of this research was to evaluate the effectivity of different levels of biofat, biochar and biosmoke against methane and other fermented products.This experiment was arranged in block randomised design. The treatments were: Control (substrate=S), Biofat: S+0.25 µLmL-1, S+0.5 µLmL-1, S+0.75 µLmL-1; Biochar: S+0.1 mgmL-1, S+0.2 mgmL-1, S+0.3 mgmL-1; Biosmoke: S + 2.5 µLmL-1, S+5.0 µLmL-1, S + level7.5 µLmL-1. Each treatment was done in duplicates and the in vitro experiment was repeated 4 times. The measured variables were: total gas production, methane production, (dry matter, organic matter, NDF) degradability, ammonia concentration (NH3) and partial VFA concentration. The results showed that biofat, biochar and biosmoke reduced methane productionas much as  43.88%, 24.21%, 37.88%  at the highest level of inclusion, respectively. NH3 slightly increased by biochar and biosmoke addition compared to control. Molar proportion of acetic acid decreased and propionic acid increased by addition of cashew nut shell bioindustrial products compared to control. Organik matter degradability decreased significantly with biofat and biosmoke addition. Different mechanisms of biofat, biochar and biosmoke were proposed in affecting rumen fermentation. It can be concluded that each bioindustrial product of cashew nut shell (biofat, biochar and biosmoke) can be utilised as feed additive to reduce methane and increase propionic acid in the rumen fermentation.