bluuebunny/crossref_metadata_2025 huggingface dataset:
Urban Metabolism of Three Cities in Jing-Jin-Ji Urban Agglomeration, China: Using the MuSIASEM Approach
Authors: Wang Xiaoyue , Wu Shuyao , Li Shuangcheng
Published: August 2017

Urban problems—such as resources depletion, environment pollution and waste generation—usually occur during rapid urbanisation processes, especially in mega-urban agglomerations. Finding solutions to sustainable urban development is a global research interest, and urban metabolism is an effective approach to analysing the socio-economic system and ecosystem. In this study, three cities in the Jing-Jin-Ji urban agglomeration in China—Beijing, Tianjin and Tangshan—were selected as study cases. Multiscale integrated analysis of the societal and ecosystem metabolism (MuSIASEM) method and complete decomposition model were applied to reveal the metabolic characteristics and evolutionary trajectories of the three cities from multiple levels and dimensions. Results showed that the metabolic patterns of Beijing, Tianjin and Tangshan were service-dominated, technology and capital aggregation-dominated and traditional industry-dominated, respectively. The evolution of economic efficiency, ecological pressure and social welfare in the three cities were different because of the stage of urban development where they were located. Tianjin and Tangshan showed positive correlations between economic growth and energy consumption, whereas Beijing demonstrated a more neutral correlation. In the future, issues—such as overpopulation, labour shortage and low efficiency of energy and labour—are likely to be the key factors that impede sustainable development in the three cities, respectively. Several policy implications were raised, including the combination of population dispersal and competitive industry relocation policies for Beijing, attracting young labour in the short term and transforming the economic growth patterns in the long term for Tianjin, and industrial upgrades and technical innovation for Tangshan.
Using Knowledge Transfer and Rough Set to Predict the Severity of Android Test Reports via Text Mining
Authors: Guo Shikai , Chen Rong , Li Hui
Published: August 2017

Crowdsourcing is an appealing and economic solution to software application testing because of its ability to reach a large international audience. Meanwhile, crowdsourced testing could have brought a lot of bug reports. Thus, in crowdsourced software testing, the inspection of a large number of test reports is an enormous but essential software maintenance task. Therefore, automatic prediction of the severity of crowdsourced test reports is important because of their high numbers and large proportion of noise. Most existing approaches to this problem utilize supervised machine learning techniques, which often require users to manually label a large number of training data. However, Android test reports are not labeled with their severity level, and manual labeling is time-consuming and labor-intensive. To address the above problems, we propose a Knowledge Transfer Classification (KTC) approach based on text mining and machine learning methods to predict the severity of test reports. Our approach obtains training data from bug repositories and uses knowledge transfer to predict the severity of Android test reports. In addition, our approach uses an Importance Degree Reduction (IDR) strategy based on rough set to extract characteristic keywords to obtain more accurate reduction results. The results of several experiments indicate that our approach is beneficial for predicting the severity of android test reports.
Risk Evaluation in Failure Mode and Effects Analysis Using Fuzzy Measure and Fuzzy Integral
Authors: Liu Haibin , Deng Xinyang , Jiang Wen
Published: August 2017

Failure mode and effects analysis (FMEA) is a popular and useful approach applied to examine potential failures in different products, designs, processes, and services. As a vital index, the risk priority number (RPN) can determine the risk priorities of failure modes by some risk factors such as occurrence (O), severity (S), and detection (D). However, in FMEA, the traditional risk priority number approach has some shortcomings, especially in setting the weight of risk factors. This paper presents an improved risk priority number approach based on a fuzzy measure and fuzzy integral. A fuzzy measure is used to reflect the importance of the individual indicators and the indicator set and a fuzzy integral is a nonlinear function defined on the basis of fuzzy measure. The weights of risk factors given by domain experts are seen as fuzzy densities to generate a λ -fuzzy measure which can reflect the weights’ difference and relevance about risk factors. Then, the Choquet integral is used to fuse every value of risk factors about failure modes so as to obtain the comprehensive evaluation result. The result can reflect the comprehensive risk level, so it has a definite physical significance. Finally, an illustrative example and a comparison with another approach are given to show the effectiveness of the proposed approach in the paper.
BATCP: Bandwidth-Aggregation Transmission Control Protocol
Authors: Amezcua Valdovinos Ismael , Perez Diaz Jesus , Garcia Villalba Luis , Kim Tai-hoon
Published: August 2017

The Transmission Control Protocol (TCP) is the most used transport protocol to exchange reliable data between network devices. A considerable number of extensions have been implemented into TCP to achieve better performance. In this paper, we will present, describe, implement, and analyze a new protocol extension called Bandwidth-Aggregation TCP (BATCP), which enables the concurrent use of network interfaces, to improve network performance on multi-homed nodes. BATCP allows the use of multiple TCP connections to accept multiple IP addresses from a multi-homed node, scheduling segments among them based on a scheduling algorithm. Our results show that BATCP achieves full exploitation of each network interface, achieving up to 100 % network utilization using two ADSL connections in real-world scenarios. MultiPath TCP (MPTCP) is currently being standardized, and achieves up to 96 % of network utilization when in ideal conditions. BATCP and MPTCP are the only protocols tested on real-world scenarios. Related work such as the Proxy Inverse Multiplexer, called PRISM, and bandwidth aggregation with Stream Control Transmission Protocol (SCTP) achieve 80 % utilization or less with network simulators.
The Preparation and Identification of a Monoclonal Antibody against Domoic Acid and Establishment of Detection by Indirect Competitive ELISA
Authors: Saeed Abdullah , Ling Sumei , Yuan Jun , Wang Shihua
Published: August 2017

Domoic acid (DA) is a potent toxin, marine biotoxin, and primarily produced by Pseudo-nitzschia. The DA hapten was coupled with bovine serum albumin (BSA), and ovalbumin (OVA) as carrier proteins. DA-BSA conjugate was used as immunogen and DA-OVA as coating antigen. Cell fusion between spleen cells and sp2/0 myeloma cells developed 1C3 hybridoma clone producing 1C3 monoclonal antibody (mAb). Hybridoma was injected into the mice to produce ascites, and further purified by caprylic acid/ammonium sulfate method. The mAb was of IgG3 subclass, and was specific to DA with high affinity (2.5 × 108 L/mol). Moreover, western blot exhibited significant specificity to the DA antigens. Indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) showed DA working range of 0.006–0.2 ng/mL. The IC50 was 0.03 ng/mL with low limit of detection (LOD) of 0.006 ng/mL. Average DA recovery from spiked shellfish extract was 100.56% ± 2.8% with the coefficient variation of 0.01–0.1%. Hence, mAb producing 1C3 hybridoma was successfully developed and could be used to detect DA in contaminated samples.
Interference of Apoptosis by Hepatitis B Virus
Authors: Lin Shaoli , Zhang Yan-Jin
Published: August 2017

Hepatitis B virus (HBV) causes liver diseases that have been a consistent problem for human health, leading to more than one million deaths every year worldwide. A large proportion of hepatocellular carcinoma (HCC) cases across the world are closely associated with chronic HBV infection. Apoptosis is a programmed cell death and is frequently altered in cancer development. HBV infection interferes with the apoptosis signaling to promote HCC progression and viral proliferation. The HBV-mediated alteration of apoptosis is achieved via interference with cellular signaling pathways and regulation of epigenetics. HBV X protein (HBX) plays a major role in the interference of apoptosis. There are conflicting reports on the HBV interference of apoptosis with the majority showing inhibition of and the rest reporting induction of apoptosis. In this review, we described recent studies on the mechanisms of the HBV interference with the apoptosis signaling during the virus infection and provided perspective.
Adaption of FMDV Asia-1 to Suspension Culture: Cell Resistance Is Overcome by Virus Capsid Alterations
Authors: Dill Veronika , Hoffmann Bernd , Zimmer Aline , Beer Martin , Eschbaumer Michael
Published: August 2017

Foot-and-mouth disease virus (FMDV) causes a highly contagious disease with catastrophic economic impact for affected countries. BHK21 suspension cells are preferred for the industrial production of FMDV vaccine antigen, but not all virus strains can be successfully propagated in these cells. Serotype Asia-1 is often affected by this phenomenon. In this study, the Asia-1 strain Shamir was used to examine viral, cellular and environmental factors that contribute to resistance to cell culture infection. Cell media composition, pH and ammonium chloride concentration did not affect Asia-1 differently than other serotypes. Virus replication after transfection of viral genome was not impaired, but the adhesion to the cells was markedly reduced for Asia-1 in comparison to serotype A. The Asia-1 Shamir virus was successfully adapted to grow in the resistant cells by using a closely related but susceptible cell line. Sequence analysis of the adapted virus revealed two distinct mutations in the capsid protein VP1 that might mediate cell attachment and entry.
Defining Runoff Indices and Analyzing Their Relationships with Associated Precipitation and Temperature Indices for Upper River Basins in the Northwest Arid Region of China
Authors: Wang Shaoping , Ding Yongjian , Iqbal Mudassar
Published: August 2017

The northwest arid region (NAR) of China, located in a cold region, has been experiencing extreme weather and runoff events for years. Summer (from June to August) is the main season for forming runoff in this region. Summer runoff is contributed by glacial runoff in addition to precipitation in glacierized basins. The upper basins of Hei River, Shule River, Kaidu River, and Manas River with different glacier coverage and available daily average discharge data were selected in this study. Two runoff indices—maximum discharge difference (MDD) and accumulated direct discharge (ADD)—were defined and calculated for each runoff event in the time series of daily average discharge during 1961–2007. To provide scientific knowledge for managing water resources and preventing disasters, the relationships between summer runoff indices and their associated precipitation and temperature variables were obtained by linear regression analysis. Results suggest that the regulation of glacier on runoff is more significant with the increase of glacier coverage.
The Impact of Cropland Balance Policy on Ecosystem Service of Water Purification—A Case Study of Wuhan, China
Authors: Mei Yun , Kong Xinghe , Ke Xinli , Yang Bohan
Published: August 2017

Urbanization has been responsible for the loss of cropland worldwide, especially in China. Since this trend is expected to continue in the near future, China has implemented the strictest cropland protection policies in the world, to guarantee its national food security. However, the negative impact of cropland protection policies on ecosystem services has always been ignored. In this paper, we used LANDSCAPE (Land System Cellular Automata model for Potential Effects) model to assess the ecological lands loss under different scenarios in Wuhan, China during S2010–2020. Our scenarios differ in whether or not the cropland protection policy is imposed. Then, the InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) model was used to calculate the amount of nutrient export under two different scenarios and to analyze the mechanism of impact of Cropland Balance Policy on water purification. Results show that the scenarios with strict cropland protection (CP) will lead to more losses of ecological lands compared with scenarios without cropland protection (NCP). Besides, the nitrogen export in the CP scenario is average 8.6% higher than the NCP scenario, which indicates that the Cropland Balance Policy has a negative impact on water purification. The nitrogen export is transported mainly by subsurface, which is 1.73 times higher than the surface averaged over the two scenarios. Accordingly, this study proposed that reasonable land use planning, and lowering the nutrient delivery ratio would be more beneficial to the ecosystem service of water purification.
On the Origin of the 3.3 μm Unidentified Infrared Emission Feature
Authors: Sadjadi Seyedabdolreza , Zhang Yong , Kwok Sun
Published: August 2017

The 3.3 μm unidentified infrared emission feature is commonly attributed to the C–H stretching band of aromatic molecules. Astronomical observations have shown that this feature is composed of two separate bands at 3.28 and 3.30 μm, and the origin of these two bands is unclear. In this paper, we perform vibrational analyses based on quantum mechanical calculations of 153 organic molecules, including both pure aromatic molecules and molecules with mixed aromatic/olefinic/aliphatic hydridizations. We find that many of the C–H stretching vibrational modes in polycyclic aromatic hydrocarbon (PAH) molecules are coupled. Even considering the uncoupled modes only, the correlation between the band intensity ratios and the structure of the PAH molecule is not observed, and the 3.28 and 3.30 μm features cannot be directly interpreted in the PAH model. Based on these results, the possible aromatic, olefinic, and aliphatic origins of the 3.3 μm feature are discussed. We suggest that the 3.28 μm feature is assigned to aromatic C–H stretch whereas the 3.30 μm feature is olefinic. From the ratio of these two features, the relative olefinic to aromatic content of the carrier can be determined.
A First Comparison of Millimeter Continuum and Mg ii Ultraviolet Line Emission from the Solar Chromosphere
Authors: Bastian T. S. , Chintzoglou G. , De Pontieu B. , Shimojo M. , Schmit D. , Leenaarts J. , Loukitcheva M.
Published: August 2017

We present joint observations of the Sun by the Atacama Large Millimeter/submillimeter Array (ALMA) and the Interface Region Imaging Spectrograph (IRIS). Both millimeter/submillimeter-λ continuum emission and ultraviolet (UV) line emission originate from the solar chromosphere and both have the potential to serve as powerful and complementary diagnostics of physical conditions in this enigmatic region of the solar atmosphere. The observations were made of a solar active region on 2015 December 18 as part of the ALMA science verification effort. A map of the Sun’s continuum emission was obtained by ALMA at a wavelength of 1.25 mm (239 GHz). A contemporaneous map was obtained by IRIS in the Mg ii h doublet line at 2803.5 Å. While a clear correlation between the 1.25 mm brightness temperature T

B
and the Mg ii h line radiation temperature T
rad is observed, the slope is <1, perhaps as a result of the fact that these diagnostics are sensitive to different parts of the chromosphere and that the Mg ii h line source function includes a scattering component. There is a significant difference (35%) between the mean T

B
(1.25 mm) and mean T
rad (Mg ii). Partitioning the maps into “sunspot,” “quiet areas,” and “plage regions” we find the relation between the IRIS Mg ii h line T
rad and the ALMA T

B
region-dependent. We suggest this may be the result of regional dependences of the formation heights of the IRIS and ALMA diagnostics and/or the increased degree of coupling between the UV source function and the local gas temperature in the hotter, denser gas in plage regions.
Effects of Electronic Word-of-Mouth on the Potential Customer's Emotions and Product Image
Authors: Tuisku Outi , Ilves Mirja , Lylykangas Jani , Surakka Veikko , Rytövuori Sanna , Ainasoja Mari , Ruohonen Mikko J.
Published: August 2017

This study investigated how potential customers (N = 28) respond to two types of electronic word-of-mouth (eWOM) regarding the same product. The study simulated reality by having participants read either mainly negative comments from an independent discussion forum (n = 14) or mainly positive comments from a marketer's website (n=14). The results showed that the participants' valence ratings were positive after reading eWOM on the marketer's website and negative after reading eWOM on the independent forum. Although this seems obvious, it is interesting that even though the comments on the independent forum were not considered trustworthy or expert, reading these comments negatively influenced the product image. Participants who read the independent forum rated the product image significantly lower than participants who read the marketer's website. After watching commercial videos, both groups rated the product image higher; however, the difference between the groups remained significant. The results suggest that the emotions evoked by eWOM play a key role in product image. A practical implication for companies may be purchasing targeted advertising on discussion forums to manage potential customers' negative affective reactions.
Game-Based Learning and Information Literacy
Authors: Wilson Scott Neal , Engler Caroline E. , Black Jessica E. , Yager-Elorriaga Derik K. , Thompson William Michael , McConnell Andrae , Cecena Javier Elizondo , Ralston Ryan , Terry Robert A.
Published: August 2017

In the 21st century, students have access to a plethora of information. As such, the skills required to access and effectively sort through this information (information literacy skills) become ever more important for success in both academic and non-academic settings. This study sought to assess the efficacy of two educational games designed to increase high school students' information literacy skills. Using a randomized controlled trial in a high school setting, the games were integrated into a standard curriculum and tested for efficacy. Post-test results indicated that both games effectively transmit targeted skills. Additionally, improved performance (relative to controls) on end-of-instruction testing (EOI; end-of-year state testing) suggest that these skills transfer across important academic domains. The study provides strong evidence to support the use of these two educational games to supplement and enhance information literacy instruction.
Mitigation of Cognitive Bias with a Serious Game
Authors: Dunbar Norah E. , Jensen Matthew L. , Miller Claude H. , Bessarabova Elena , Lee Yu-Hao , Wilson Scott N. , Elizondo Javier , Adame Bradley J. , Valacich Joseph , Straub Sara , Burgoon Judee K. , Lane Brianna , Piercy Cameron W. , Wilson David , King Shawn , Vincent Cindy , Schuetzler Ryan M.
Published: August 2017

One of the benefits of using digital games for education is that games can provide feedback for learners to assess their situation and correct their mistakes. We conducted two studies to examine the effectiveness of different feedback design (timing, duration, repeats, and feedback source) in a serious game designed to teach learners about cognitive biases. We also compared the digital game-based learning condition to a professional training video. Overall, the digital game was significantly more effective than the video condition. Longer durations and repeats improve the effects on bias-mitigation. Surprisingly, there was no significant difference between just-in-time feedback and delayed feedback, and computer-generated feedback was more effective than feedback from other players.
The Effects of Vertical Stress on the Liquefaction Potential Originated from Buildings in The Urban Areas
Authors: Ozcelik Mehmet
Published: August 2017

Main purpose of this paper is to study the influence of vertical stress on soil liquefaction in urban areas. The literature provides limited information on vertical stress analysis of multiple footings, and, as a result, there is no accurate way to account for the effect of the foundation depth on liquefaction. Additionally, practical methods do not exist for considering the interaction between the neighboring foundations vertical stress and seismic forces in the urban area. Vertical stress distribution was calculated in examining the soil liquefaction potential exhibited by building foundations as a case study. The vertical stresses were chosen randomly for some buildings with foundation depths of 3.00 m; 4.50 and 6.00 m at the Burkent site (Burdur-Turkey). The influence of 5-storey buildings on the liquefaction potential of sandy soils was evaluated in terms of the safety factor (FS) against liquefaction along soil profile depths for different earthquakes. Standard Penetration Test (SPT) results were used based on simplified empirical procedure.
A New Intelligent Optimization Network Online Learning Behavior in Multimedia Big Data Environment
Authors: Heng Shao
Published: August 2017

In the era of multimedia big data, the online learning behavior of users becomes rich and colorful. This paper proposes a hybrid clonal selection differential evolution optimization algorithm based on clonal selection algorithm and differential evolution in multimedia big data environment. The proposed intelligent optimization algorithm treats each e-learning behavior of the user as an antibody, and gets the best results of multimedia big data mining by a number of iterative searches. Experimental results show the feasibility and effectiveness of the proposed intelligent optimization algorithm.
A Novel Fast Hierarchical Projection Algorithm for Skew Detection in Multimedia Big Data Environment
Authors: Cheng Li , Wu Gongping
Published: August 2017

Optical character recognition is an effective way for information input of paper media and skew detection of document images is a key stage of it. An algorithm for skew detection employing hierarchical projection is proposed in this paper. Projection histograms at various directions in a given range are acquired according to an initial angle step length. Then variances of it and absolute difference of the variances are calculated respectively and the angle corresponding to the maximum difference is served as rough skew estimate. The similar work above is implemented in which the projection angle range is two times the initial step length and symmetric about the estimate. Finally, the maximum value of the variances is found and the angle corresponding to it is served as skew angle. Experimental results show the algorithm has such advantages as fast processing speed, high detection accuracy, insensitivity to noise and suitable for complex layout.
Empirical Study on the Determinants of Industrial Research and Development Expenditures
Authors: Yamada Hirokazu
Published: August 2017

This study focuses on the wide range of manufacturing industries in Japan and hypothesized the numerous factors external to a corporation particularly for abstracting the determinants of research and development (R&D) expenditures. Previous studies primarily dealt with internal corporate factors such as sales, operating profits, or diversification. This study selected, integrated, and performed multiple regression analyses for nine industries based on the panel data concerning R&D expenditures. This resulted in the abstraction of statistically significant factors. R&D expenditures in the preceding term are an internal factor. This could be considered a comprehensive and continuous indicator of the scale of a corporation, its performance, its fixed R&D expenditures and corporate strategies. External factors cited are growth of the market, competitiveness, export dependency, labor intensity, and whether products are directed toward end-customers. This study would especially aid in deciding the R&D strategy as an aspect of the company expenses.
Prediction of Crater Size in Drilling and Texturing by Pulsed Laser Ablation
Authors: Stathatos Emmanuel , Vosniakos George Christopher , Pantelis Dimitris
Published: August 2017

In laser processing of surfaces, typically to impart some texture or to drill shallow holes, it is necessary to correlate pulse properties (wavelength, power, beam radius and quality, duration) and material properties (reflectivity, melting temperature, conductivity, diffusivity) mainly with the depth of the formed crater. Crater shape is assumed to be paraboloidal and its maximum diameter is assumed to be uniquely related to its depth. An empirical and an analytical model are suggested to this end. The former entails construction of Artificial Neural Networks from experimental measurements, whilst the latter entails modification of established models from literature. Both types of models are exemplified in this paper drawing on data from available literature.
Making Twist-Free Surfaces by Magnetic Assisted Ball Burnishing
Authors: Kovács Zsolt Ferenc , Viharos Zsolt János , Kodácsy János
Published: August 2017

As a well-known conventional finishing process, the grinding is commonly used to manufacture seal mating surfaces and bearing surfaces. It would lead to generate another finishing machining, which more cost-and energy-efficient, so the grinding process could be replaced by machining with roller burnishing or special type of polishing. The machined surfaces by turning or grinding usually have twist structure on the surfaces, which can convey lubricants such as conveyor screw. To avoid this phenomenon have to use special kind of techniques or machine, for example, rotation turning, tangential turning, ultrasonic protection or special toll geometries. All of these solutions have a high cost and difficult usability. In this paper, the authors describe a system and summarize the results of the experimental research carried out mainly in the field of Magnetic Abrasive Polishing (MAP) and Magnetic Roller Burnishing (MRB). These technologies are simple and also cheap while result the twist-free surfaces. During the tests, C45 normalized steel was used as workpiece material which was machined by simple and Wiper geometrical turning inserts in a CNC turning lathe. After the turning was used the MAP and MRB technologies to reduce the twist of surfaces. The evaluation was completed by advanced measuring and IT equipment.
Influence of Ultrasound on Delamination during Machining of GFRP Composite Material
Authors: Kuruc Marcel , Šimna Vladimír , Necpal Martin , Vopát Tomáš , Peterka Jozef
Published: August 2017

In many present applications is requested decreasing of weight of components and increasing of their strength. Often unique properties are required. These properties could be solved by using of composite materials. However, different material properties of matrix and reinforcing material cause issues during machining, such as rapid tool wear and delamination of composite. Therefore there is afford to enhance machining process by different ways to decrease tool wear as well as delamination of composite. This article deals with comparison of conventional milling and ultrasonic assisted milling of glass fibre reinforced polymer (GFRP) composite material by special designed cutting tool.
An Intelligent Prediction of Surface Roughness on Precision Grinding
Authors: Ding Ning , Zhao Chang Long , Luo Xi Chun , Li Qing Hua , Shi Yao Chen
Published: August 2017

Precision grinding is generally used as the final finishing process, and it determines the surface quality of the machined component. It’s very difficult to achieve on-line measurement of the surface roughness. The purpose of this research was to study the surface roughness prediction and avoid the defect happening in the grinding process. A surface roughness prediction model was proposed in this paper, which presented the relationship between surface roughness and the wear condition of grinding wheel and grinding parameters. An AE sensor was used to collect the grinding signals during the grinding process to obtain the grinding wheel wear condition. Besides, a fuzzy neural network was used to obtain the prediction surface roughness. Grinding trials were performed on a high precision CNC cylindrical grinder (MGK1420) to evaluate the surface roughness prediction model. Experiment verified that the developed prediction system was feasible and had high prediction accuracy.
Effect of Substrate Bias and Coating Thickness on the Properties of nc-AlCrN/a-SixNy Hard Coating and Determination of Cutting Parameters
Authors: Vopát Tomáš , Haršáni Marián , Kuruc Marcel , Šimna Vladimír , Zaujec Rudolf , Peterka Jozef , Čaplovič Ľubomír
Published: August 2017

Nitride hard coatings Al25.5Cr21Si3.5N were deposited on WC-Co substrates with a different thickness and a negative substrate bias voltage by the LAteral Rotating Cathodes Arc technology. The nanoindentation tests were performed for analysis of AlCrSiN coatings in order to determine the most promising combination of parameters for subsequent machining. On the basis of results of nanohardness measurement and Ratio H/E*, which represents the resistance to plastic deformation and cracking, deposition conditions were selected for coating of turning cemented carbide inserts. For the evaluation of coating adhesion to substrate, Mercedes adhesion test was used. Chip forming tests and long-term tool life tests were performed for determination of cutting parameters (cutting speed, feed rate and depth of cut) for AlCrSiN coated cemented carbide inserts when machining austenitic stainless steel material.
Application of Neuro-Fuzzy Systems for Modeling Surface Roughness Parameters for Difficult-to-Cut-Steel
Authors: Kovač Pavel , Savković Borislav , Rodić Dragan , Gostimirović Marin , Sekulić Milenko , Ješić Dušan
Published: August 2017

The objective of this study is to examine the influence of machining parameters on surface finish in turning difficult-to-cut-steel. A new approach in modeling surface roughness which uses design of experiments is described in this paper. The values of surface roughness predicted by different models are then compared. Adaptive-neuro-fuzzy-inference system (ANFIS) was used. The results showed that the proposed system can significantly increase the accuracy of the product profile when compared to the conventional approaches. The results indicate that the design of experiments with central composition plan modeling technique can be effectively used for the prediction of the surface roughness for difficult-to-cut-steel.
Selection Criteria of Optimal Characteristic Material and Technologies for Precision Processing of Basic Working Surface of Human Hip-Joint Implant
Authors: Turmanidze Raul , Popkhadze Giorgi
Published: August 2017

In view of the fact that the endo-prosthesis heads of human hip-joint are operated in extreme conditions, in respect of load, the selection of corresponding material and also increase of precision and quality of machining of spherical surfaces is rather topical task.In the submitted work are reviewed the problems connected with definition of the influence degree of orientation of the sapphire crystal on its workability during diamond grinding with a butt of the ring and elaboration of the perspective, original scheme of formation of the incomplete spherical surface, particularly, of the sapphire head of endo-prosthesis of the human hip-joint.
Effects of Technological Parameters on Surface Characteristics in Face Milling
Authors: Varga Gyula , Kundrák János
Published: August 2017

The experimental and theoretic examination of conventional manufacturing procedures continue to be a topic of modern research. It is assisted, to a great extent, by the spread and the possibility of the application of high level software and more accurate measuring equipment. The research results obtained by the use of new equipment can open new ways for further development of conventional manufacturing procedures and their more intensive, more productive application. In this paper, an experimental method is used for examination of the surface features (e.g. flatness, 2D and 3D surface roughness parameters) of face milled aluminium parts. The aim of experiments was to determine the effect of change of the technological parameters (feed rate and cutting speed) on flatness and surface roughness features in of face milling of aluminium parts.
A New Strategy in Face Milling - Inverse Cutting Technology
Authors: Karpuschewski Bernhard , Kundrák János , Emmer Thomas , Borysenko Dmytro
Published: August 2017

The article describes a new technology in milling of the flat surfaces - Inverse Cutting Technology. The theoretical basics of the inverse cutting are formulated. The boundary conditions of the process depending on the cutting parameters are presented. The chip formation and chip flow by inverse milling are simulated. The comparison of cutting forces by conventional and inverse face milling is shown. Finally, cutting experiments were conducted to confirm the results of the 3D-FEM-simulation.
Finite Element Analysis of Tool Stresses, Temperature and Prediction of Cutting Forces in Turning Process
Authors: Necpal Martin , Pokorný Peter , Kuruc Marcel
Published: August 2017

The paper presents the simulation model of turning the process of C45 non-alloy steel with a tool made of carbide insert. A 3D final element model used a lagrangian incremental type and re-meshing chip separation criterion was experimentally verified by measure cutting forces using piezoelectric dynamometer. In addition, stresses and temperature in the tooltip were predicted and examine. This work could investigate failure the tooltip, which would be great interest to predict wear and damage of cutting tool.
Analysis of Helical Torsion Spring for Epicyclic Traction Drive
Authors: Nemeth Geza
Published: August 2017

Let us consider a simple epicyclic traction drive containing a sun wheel, an annular wheel, planetary wheels and a planet carrier. The annular wheel is substituted by a helical torsion spring with rectangular cross section. The spring has initial tensioning, tightened to the planetary wheels. When the number of coils is z and the number of planet wheels is N, there are zN piece of concentrated forces acting to the spring from inside towards outside. The main load of the spring is bending, it is computable along the spring wire. The bending moment is limited by the spring material and the cross section of spring. The radial forces acting to the spring are governed by the constraint of stress equality, the deflections of the contacting parts are determined by the radial (and slightly the tangential) forces. An initial shape of the spring that assures the proper operation of the drive after the assembly, is calculated by elementary mechanical calculation methods. The main goal is the developing of a traction drive in which the clamping force is proportional to the torque which should be transmitted, for the sake of the favourable life rating and the efficiency.
Effect of X-Ray µCT Scanning on the Growth and Activity of Microorganisms in a Heap Bioleaching System
Authors: Ghadiri Mehdi , Harrison Susan T.L. , Fagan-Endres Marijke A.
Published: August 2017

In heap bioleaching, a process in which microorganisms are required for the regeneration of leach reagents and control of reaction products, inaccessibility of non-surface mineral grains is a key cause of low recovery and long extraction times. High resolution, non-destructive 3D X-ray micro-computed tomography (μCT) is an imaging technique that has been successfully demonstrated for the study of abiotic leaching of non-surface minerals. For this technique to be applied to biotic leaching, it is required that the iron and sulphur oxidizing abilities of the microorganisms are not affected by the irradiation experienced. In the current study, the feasibility of investigating biotic leaching by X-ray μCT is explored by examining the relative energies required to achieve the high image resolution needed for mineral grain mapping while avoiding microbial deactivation. A mixed mesophilic and moderately thermophilic culture in solution was used and exposed to various X-ray energy doses. Direct microscopic cell counting and redox potential were measured to quantify the microbial activity and growth. The results showed that exposure to X-ray does not affect microbial activity at 35-90 kV, 200-280 μA and a distance of 7.2 cm between energy source and sample, however, it has an influence at 120 and 150 kV. This indicates that while X-ray μCT does influence the microbial cultures, it can be used for bioleaching studies at lower energy doses.
The Use of Heap Bioleaching as a Pre-Treatment for Platinum Group Metal Leaching
Authors: Mwase James M. , Petersen Jochen
Published: August 2017

Two samples, a Platreef flotation concentrate and coarse ore (<6 mm), were column bioleached at 65°C using a culture dominated by Metallosphaera hakonensis. Based on solution assays, extractions in excess of 90% Cu and Ni were achieved from the flotation concentrate, while from the coarse ore 96% Cu and 67% Ni extractions were achieved. The difference in extraction levels and leaching patterns despite identical conditions used for both samples is discussed, as is the performance of the samples during a follow-up leach step using cyanide to extract the PGMs in a separate column leach experiment. While the recovery of Pd and Au was excellent during these steps, recovery of Pt was limited to 35% after 45 days for the concentrate and 56% after 60 days for the whole ore material, primarily due to the presence of a refractory Pt mineral. Recovery from a concentrate without pre-treatment was substantially lower.
Effect of Marmatite on Bioleaching Behaviors of Chalcopyrite
Authors: Liao Rui , Wang Jun , Zhao Hong Bo , Wang Xing Xing , Huang Xiao Tao , Hong Mao Xin
Published: August 2017

Bioleaching experiments were used in this experiment to study the interaction between marmatite and chalcopyrite. In the sterile system, the copper extraction rate of single chalcopyrite was only 20%, much lower than the copper extraction rate of L. ferriphilum system, which is 95%. The addition of L. ferriphilum can improve the copper extraction rate to a substantial level. In both the sterile and L. ferriphilum system, the single chalcopyrite got a higher copper extraction rate than the mixture minerals of chalcopyrite and marmatite, and with the increase of marmatite, the copper extraction rate decreased. So marmatite may inhibit the dissolution of chalcopyrite. The reason may be that the redox potential of mixture mineral was not in the optimum range.
Method for the Recovery of Indium from Diluted Bioleaching Solutions
Authors: Vostal Radek , Šingliar Ute , Bertau Martin
Published: August 2017

Using a commercially available solvent impregnated resin, Lewatit TP272, in an ion exchange process, it was possible to extract up to 90 % indium from a feed containing as little as 1 mg/L indium in the presence of high amounts of impurities, i.e. 1000 mg/L iron and zinc each. It was demonstrated that through gradient regeneration of obtained loaded ion-exchange resin, it is possible to yield a solution containing as much as 400 mg/L indium along with 400 mg/L iron, thereby upgrading its purity more than 600 times. Moreover, it was shown that this solution can be fed into an existing solvent extraction procedure which would yield an indium oxide with more than 99 % purity.
Mechanism of Silver-Catalyzed Bioleaching of Enargite Concentrate
Authors: Oyama Keishi , Hirajima Tsuyoshi , Sasaki Keiko , Miki Hajime , Okibe Naoko
Published: August 2017

Silver-catalyzed bioleaching of enargite concentrate with three bacteria (Acidimicrobium ferrooxidans ICP, Sulfobacillus sibiricus N1, Acidithiobacillus caldus KU) and one archaeon (Ferroplasma acidiphilum Y) was conducted in order to elucidate the catalytic mechanism of silver sulfide in enargite bioleaching. Whereas Cu recovery remained relatively low (43%) and Fe dissolved completely without silver sulfide, Cu recovery was greatly enhanced (96%) and Fe dissolution was suppressed (29%) in the presence of 0.04% silver sulfide. In the latter case, 52% of the solubilized As was re-immobilized, in contrast to only 14% As re-immobilization in the former. The silver-catalyzed bioleaching (at 0.04% silver sulfide) proceeded at low redox potentials within the optimal range, which likely promoted enargite dissolution via formation of intermediate Cu2S. XAFS analysis revealed that As was mainly immobilized as As (V), which was in agreement with the EPMA results detecting ferric arsenate passivation on some enargite grains. Furthermore, formation of trisilver arsenic sulfide (Ag3AsS4) was detected by XRD and EPMA, covering the surface of enargite particles. An intermediate layer, consisting of (Cu,Ag)3AsS4, was also observed between the enargite grain and trisilver arsenic sulfide layer, implying that Cu in enargite may be gradually substituted by solubilized Ag. The overall mechanism of silver-catalyzed bioleaching of enargite concentrate will be proposed.
Proteins Binding to Immobilized Rusticyanin Detected by Affinity Chromatography
Authors: Kucera Jiri , Janiczek Oldrich , Smoldas Jan , Mandl Martin
Published: August 2017

Recombinant rusticyanin was produced in Pichia pastoris, then purified and immobilized on Sepharose CL-4B with periodate activation. Cellular lysate of acidophilic Acidithiobacillus ferrooxidans was applied to an affinity column with immobilized rusticyanin. Rusticyanin-binding proteins, separated using 1D PAGE and identified by mass spectrometry, included anticipated interacting partners, such as cytochromes Cyc1 and Cyc2, which are involved in the downhill electron pathway from ferrous iron to oxygen. However, the results indicate that rusticyanin’s functional protein-protein interaction (PPI) network could be more complex than expected, including various proteins involved in different cellular processes. Although affinity purification coupled to mass spectrometry should mostly detect proteins that bind stably, and thus are likely participants in functional in vivo PPIs, further verification is needed to exclude non-functional interactants. Nevertheless, our preliminary PPI data confirm some previous experimental findings and indicate potentially fruitful directions for probing additional roles of rusticyanin in sulfur metabolism, copper resistance, anaerobic iron reduction, iron transport, and oxidative stress in extreme acidophiles.
Bioleaching of Pyrite by Iron-Oxidizing Acidophiles under the Influence of Reactive Oxygen Species
Authors: Huynh Dieu , Bellenberg Sören , Vera Véliz Mario , Poetsch Ansgar , Sand Wolfgang
Published: August 2017

After 24h of exposure to acidic media, pyrite generates reactive oxygen species (ROS). Freshly-crushed pyrite with grain sizes between 50-100 μm at a 5 % (w/v), pulp density generated 0.17 ± 0.01 mM H2O2, while 10% pyrite generated 0.29 ± 0.01 mM and 30 % pyrite generated approximately 0.83 ± 0.06 mM. These levels of H2O2 inhibit iron oxidation in iron-grown cells of AcidithiobacillusferrooxidansT but not in pyrite-grown cells. ROS originating from pyrite, which was incubated for 24 h in acidic medium, prohibited pyrite dissolution by iron-grown cells, while pyrite-grown cells were adapted to these concentrations of ROS. Periodical addition of 100 μM H2O2 to pyrite cultures inoculated with pyrite-grown cells did not lower iron dissolution as it was observed with iron-grown cells. By high throughput proteomics analysis, an increased expression of proteins related to oxidative stress management, iron-and sulfur oxidation systems, carbon fixation and biofilm formation was observed in biofilm cells grown on pyrite compared to iron-grown cells.
Use of Specific Metal Binding of Self-Assembling S-Layer Proteins for Metal Bioremediation and Recycling
Authors: Vogel Manja , Matys Sabine , Lehmann Falk , Drobot Björn , Günther Tobias , Pollmann Katrin , Raff Johannes
Published: August 2017

Most bacteria and all archaea possess as outermost cell envelope so called surface-layers (S-layers). These layers were formed by self-assembling proteins having a number of habitat depending interesting intrinsic properties. As example, S-layers from bacterial isolates recovered from heavy metal contaminated environments have outstanding metal binding properties and are highly stable. Thus they selectively bind several metals with different affinity. For using S-layer proteins for metal bioremediation and recycling three aspects of the metal-interactions with S-layer proteins must be taken into account. First, S-layers possess different functionalities, e.g. carboxyl, phosphoryl groups, binding toxic metals and metalloids, like U(VI) and As(V), nonspecifically depending on pH. Second, precious metals like Au and Pd are likewise nonspecifically bound to functional groups, but presumably covalently, making the binding irreversible. Third, intrinsic specifically bound metals, e.g. Ca2+, are needed for native protein folding, self-assembly, and the formation of highly-ordered lattices. Their binding sites also allow selective binding of chemical-equal elements including the trivalent rare earth elements, possessing comparable ionic radii. Thus this study combines older and recently generated results regarding the metal dependent binding behavior of the S-layer proteins. It enables the development of biohybrid materials for the separation, removal or recovery of strategic relevant metals from natural occurring or industrial waste waters using pH-value as regulating parameter for selective metal binding and also conceivably release.
The Mechanism of Skutterudite Acid Leaching: A DFT Study of H+ Effect on CoO (010) Surface
Authors: Xu Jia Ning , Yang Hong Ying , Tong Lin Lin , Jin Zhe Nan , Song Yan
Published: August 2017

A DFT study of H+ effect on CoO(0 1 0) surface was carried out. What could be seen from the inter atomic distance and the density of states (DOS) was: Co-O bonds were broken strongly and H-O bonds formed strongly when one H+ was adsorbed on the O atom, and Co-O bonds were not broken and H-O bond not formed strongly when two H+ were adsorbed on the O atom, so the Skutterudite acid leaching process cannot be described as two H+ were adsorbed on the O atom and formed the H2O molecules to enter the solution. But that can be described as one H+ was adsorbed on the O atom and formed the OH- to enter the solution, the OH- was combined with the H+ in the solution to form the H2O molecule.