bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of sulfuric and hydrochloric acid on the resistance of geopolymer cement with nano-silica additive for oil well cement application
Authors: Ridha Syahrir , Abd Hamid Afif Izwan , Setiawan Riau Andriana , Shahari Ahmad Radzi
Published: August 2018

Purpose

The purpose of this paper is to investigate the resistivity of geopolymer cement with nano-silica additive toward acid exposure for oil well cement application.

Design/methodology/approach

An experimental study was conducted to assess the acid resistance of fly ash-based geopolymer cement with nano-silica additive at a concentration of 0 and 1 wt.% to understand its effect on the strength and microstructural development. Geopolymer cement of Class C fly ash and API Class G cement were used. The alkaline activator was prepared by mixing the proportion of sodium hydroxide (NaOH) solutions of 8 M and sodium silicate (Na2SiO3) using ratio of 1:2.5 by weight. After casting, the specimens were subjected to elevated curing condition at 3,500 psi and 130°C for 24 h. Durability of cement samples was assessed by immersing them in 15 wt.% of hydrochloric acid and 15 wt.% sulfuric acid for a period of 14 days. Evaluation of its resistance in terms of compressive strength and microstructural behavior were carried out by using ELE ADR 3000 and SEM, respectively.

Findings

The paper shows that geopolymer cement with 1 wt.% addition of nano-silica were highly resistant to sulfuric and hydrochloric acid. The strength increase was contributed by the densification of the microstructure with the addition of nano-silica.

Originality/value

This paper investigates the mechanical property and microstructure behavior of emerging geopolymer cement due to hydrochloric and sulfuric acids exposure. The results provide potential application of fly ash-based geopolymer cement as oil well cementing.
Why do listed companies delist themselves voluntarily?
Authors: Konno Yukiko , Itoh Yuki
Published: August 2018

Purpose

This study aims to analyse, from a corporate finance and governance perspective, the reasons why managers decide to delist their companies from a stock exchange. On the basis of the five hypotheses of voluntary delisting, this study examines why listed companies delist themselves voluntarily in the construction and real estate sectors.

Design/methodology/approach

By using actual data to examine contractors and real estate companies listed on the Tokyo Stock Exchange between 2004 and 2014, this study analyses whether these companies delist themselves voluntarily. The pooled binary logit model is used as the statistical method.

Findings

In both the construction and real estate sectors, the concentration of shareholders has a significantly positive effect on voluntary delisting, thus supporting the transfer of wealth effect hypothesis. In construction, market capitalisation has a significantly negative effect on voluntary delisting, thus supporting the maintenance cost reduction hypothesis. In the real estate sector, the ratio of market capitalisation to total assets has a significantly negative effect on voluntary delisting, thus supporting the undervalue elimination hypothesis.

Originality/value

By comparing the construction and real estate sectors, this study reveals both unique and common reasons for voluntary delisting in each sector. It also offers valuable insights to managers, regulators setting standards in securities markets and investors.
Infrastructure financing and economic growth in India: an empirical investigation
Authors: Chotia Varun , Rao N.V.M.
Published: August 2018

Purpose

This paper aims to suggest the preferred mode of financing for major sub-sectors of infrastructure: roads, seaports, telecommunication and energy by examining which mode of infrastructure financing – public, private or public–private partnership (PPP) – has the maximum positive impact on the overall GDP of India. The same exercise was carried out for the overall infrastructure sector by integrating data from all the four sub-sectors.

Design/methodology/approach

The structural vector autoregressive approach was used with the period of analysis taken from 1995 to 2014. The stationary properties of the variables were checked by the Phillips–Perron unit root.

Findings

The PPP mode of financing was found to make the maximum positive impact on the GDP of India. Considering the four sub-sectors individually, it was concluded that the private mode of financing in roads, energy and telecom sectors has the maximum positive impact on the GDP, while the PPP gives optimal benefit to the seaports sector.

Practical implications

Results will aid the Indian Government and policymakers to efficiently design and develop their economic policies accordingly.

Originality/value

The study is novel in a sense that it helps to address the lack of research into the area of infrastructure financing in India.
Female accounting students and their academic performance: evidence from Kuwait
Authors: Alanzi Khalid A.
Published: August 2018

Purpose

This study aims to compare the academic performance of female accounting students with their male counterparts and to assess the impact and association between gender and the academic performance of accounting students graduating from the College of Business Studies (CBS) in Kuwait.

Design/methodology/approach

The sample consisted of 141 accounting students, who graduated during 2015 from CBS. Independent samples test, correlation and linear least squares regression analyses tested the hypotheses.

Findings

The results indicate that there was a statistically significant association between gender and accounting students’ performance, which explained the superiority of the performance of the female students’ group over the performance of the male students’ group and explained the significant impact of gender on accounting students’ performance, with and without controls for other factors.

Practical implications

The findings have practical implications for how the administration of CBS and similar educational institutions should take action. The findings suggest that the administration of CBS should adopt policies that impose and encourage the acceptance of more female accounting students, as they perform well in accounting and their academic performance is better than their male counterparts.

Originality/value

The study makes significant contributions to the existing knowledge in the area of students’ performance by empirically supporting the theoretical expectation of the impact of gender on accounting students’ performance. It provides a foundation for future comparative studies, potentially leading to the harmonization of international accounting education. It also addresses some of the shortfalls in the existing regional accounting education literature resulting from the scarcity of prior studies, where little has been published.
The influence of ethical leadership on academic employees’ organizational citizenship behavior and turnover intention
Authors: Shareef Raad Abdulkareem , Atan Tarik
Published: August 2018

Purpose

The purpose of this paper is to examine the effect of ethical leadership on followers’ organizational citizenship behavior (OCB) and turnover intention and to examine the mediating role of intrinsic motivation in the relationships.

Design/methodology/approach

The study employed a quantitative research method with a sample of 351 supervisor–subordinate dyads in three large public universities in the Kurdistan Region of Iraq. The statistical analysis was conducted using Statistical Package for Social Science software, through multiple regression analyses to test the research hypotheses.

Findings

The results indicated that ethical leadership positively related to OCB and negatively related to turnover intentions. The results also showed that intrinsic motivation fully mediates the relationship between ethical leadership, OCB, and turnover intentions.

Originality/value

This study recognized the gap in the literature, and it contributes to the body of knowledge through an examination of the mediating role of intrinsic motivation between ethical leadership, OCB and turnover intention, relying on the cognitive evaluation theory.
Factors Affecting the Price of Commercial Housing in Haikou Housing
Authors: Wu Ji-Yan , Zheng Wan-Yin , Zeng Xu-You
Published: August 2018

This paper uses the grey correlation degree and factor analysis method to carry out empirical research on the main influencing factors of residential price extraction in Haikou City according to the data of Haikou City from 2013 to 2018 as a sample. The research results show that the factors affecting housing prices can be divided into two aspects. From the economic level, the impact of population, regional GDP and per capita disposable income are positive effects. They promote economic growth to increase housing prices. From the perspective of expenditure levels, expected housing prices, investment costs, and consumer price index will affect housing prices by influencing consumers and investors spending decisions. On the whole, the key factors affecting house prices are mainly policies, population movements, economic growth, and total investment costs.
On Rate Boundary Conditions for Soft Tissue Bifurcation Analysis
Authors: Emuna Nir , Durban David
Published: August 2018

Mechanical instability of soft tissues can either risk their normal function or alternatively trigger patterning mechanisms during growth and morphogenesis processes. Unlike standard stability analysis of linear elastic bodies, for soft tissues undergoing large deformations it is imperative to account for the nonlinearities induced by the coupling between load and surface changes at onset of instability. The related issue of boundary conditions, in context of soft tissues, has hardly been addressed in the literature, with most of available research employing dead-load conditions. This paper is concerned with the influence of imposed homogeneous rate (incremental) surface data on critical loads and associated modes in soft tissues, within the context of linear bifurcation analysis. Material behavior is modeled by compressible isotropic hyperelastic strain energy functions (SEFs), with experimentally validated material parameters for the Fung–Demiray SEF, over a range of constitutive response (including brain and liver tissues). For simplicity, we examine benchmark problems of basic spherical patterns: full sphere, spherical cavity, and thick spherical shell. Limiting the analysis to primary hydrostatic states we arrive at universal closed-form solutions, thus providing insight on the role of imposed boundary data. Influence of selected rate boundary conditions (RBCs) like dead-load and fluid-pressure (FP), coupled with constitutive parameters, on the existence and levels of bifurcation loads is compared and discussed. It is argued that the selection of the appropriate type of homogeneous RBC can have a critical effect on the level of bifurcation loads and even exclude the emergence of bifurcation instabilities.
Real-Time Trajectory Generation for Haptic Feedback Manipulators in Virtual Cockpit Systems
Authors: Zhang Shiyu , Dai Shuling
Published: August 2018

To obtain real-time interactions in the virtual cockpit system (VCS), a real-time trajectory generation method based on dynamical nonlinear optimization and regression prediction for the haptic feedback manipulator (HFM) is presented in this paper. First, a haptic feedback system based on servoserial manipulator is constructed. Then, the trajectory planning problem for the HFM is formulated as a nonlinear optimization problem to balance the motion time and power consumption and ensure the safety of physical human–robot interactions (pHRI). Multiple optimization problems are solved to generate the optimal database off-line. Finally, the classified multivariate (CM) regression method is presented to learn the database and generate optimal trajectories with arbitrary initial and objective positions on-line. Results show that trajectories with rapidity, safety, and lower power consumption can be generated in real-time by this method, which lay a basis of haptic interactions in the VCS.
Passive, Consultative, and Coconstructive Methods: A Framework to Facilitate Community Participation in Design for Development
Authors: Mazzurco Andrea , Leydens Jon A. , Jesiek Brent K.
Published: August 2018

The complexity of design for development (D4D), humanitarian engineering (HE), and similar projects emerges from multiple sources, including the overarching requirement to address complex sociotechnical problems by effectively engaging community members. However, missing from the literature on enacting D4D/HE projects is a clear framework that classifies extant community participation methods based on key characteristics, especially vis-à-vis level of community participation in problem definition and solution processes. To address this lack of a classification framework, we first conducted a systematized literature search to identify methods used in D4D/HE projects. This literature search resulted in 64 identified methods. Following an iterative, inductive, and systematic process to develop classification systems combined with content analysis, a bidimensional framework emerged to classify the methods. The first dimension of the framework organizes methods according to a spectrum of three levels of community engagement: (1) passive, (2) consultative, and (3) coconstructive. The second dimension classifies methods based on the part of the design process in which it is most appropriate to use them. We conclude the paper by discussing considerations engineers should reflect upon when using the framework to inform their projects, as well as opportunities for future research.
Reliability-Based Design Optimization on Qualitative Objective With Limited Information
Authors: Meselhy Khaldon T. , Wang G. Gary
Published: August 2018

Reliability-based design optimization (RBDO) algorithms typically assume a designer's prior knowledge of the objective function along with its explicit mathematical formula and the probability distributions of random design variables. These assumptions may not be valid in many industrial cases where there is limited information on variable variability and the objective function is subjective without mathematical formula. A new methodology is developed in this research to model and solve problems with qualitative objective functions and limited information about random variables. Causal graphs and design structure matrix are used to capture designer's qualitative knowledge of the effects of design variables on the objective. Maximum entropy theory and Monte Carlo simulation are used to model random variables' variability and derive reliability constraint functions. A new optimization problem based on a meta-objective function and transformed deterministic constraints is formulated, which leads close to the optimum of the original mathematical RBDO problem. The developed algorithm is tested and validated with the Golinski speed reducer design case. The results show that the algorithm finds a near-optimal reliable design with less initial information and less computation effort as compared to other RBDO algorithms that assume full knowledge of the problem.
Working
Fluid Selection and Technoeconomic Optimization of a Turbocompression Cooling
System
Authors: Young Derek , Gibson Spencer
C. , Bandhauer Todd
M.
Published: August 2018

Low grade waste heat recovery presents an opportunity to utilize typically wasted energy to reduce overall energy consumption and improve system efficiencies. In this work, the technoeconomic performance of a turbocompression cooling system (TCCS) driven by low grade waste heat in the engine coolant of a large marine diesel generator set is investigated. Five different working fluids were examined to better understand the effects of fluid characteristics on system performance: R134a, R245fa, R1234ze(E), R152a, and R600a. A coupled thermodynamic, heat exchanger, and economic simulation was developed to calculate the simple payback period of the waste heat recovery system, which was minimized using a search and find optimization routine with heat exchanger effectiveness as the optimization parameter. A sensitivity study was performed to understand which heat exchanger effectiveness had the largest impact on payback period. Of the five working fluids examined, a TCCS with R152a as the working fluid had the lowest payback period of 1.46 years with an initial investment of $181,846. The R152a system was most sensitive to the two-phase region of the power cycle condenser. The R1234ze(E) system provided the largest return on investment over a ten year lifetime of $1,399,666.
Post-Buckling Failure Modes of X65 Steel Pipe: An Experimental and Numerical Study
Authors: Mohajer Rahbari Nima , Xia Mengying , Liu Xiaoben , Cheng J. J. Roger , Sen Millan , Adeeb Samer
Published: August 2018

In service pipelines exhibit bending loads in a variety of in-field situation. These bending loads can induce large longitudinal strains, which may trigger local buckling on the pipe's compressive side and/or lead to rupture of the pipe's tensile side. In this article, the post-buckling failure modes of pressurized X65 steel pipelines under monotonic bending loading conditions are studied via both experimental and numerical investigations. Through the performed full-scale bending test, it is shown that the post-buckling rupture is only plausible to occur in the pipe wall on the tensile side of the wrinkled cross section under the increased bending. Based on the experimental results, a finite element (FE)-based numerical model with a calibrated cumulative fracture criterion was proposed to conduct a parametric analysis on the effects of the internal pressure on the pipe's failure modes. The results show that the internal pressure is the most crucial variable that controls the ultimate failure mode of a wrinkled pipeline under monotonic bending load. And the post-buckling rupture of the tensile wall can only be reached in highly pressurized pipes (hoop stress no less than 70% SMYS for the investigated X65 pipe). That is, no postwrinkling rupture is likely to happen below a certain critical internal pressure even after an abrupt distortion of the wrinkled wall on the compressive side of the cross section.
Parametric Reduced Order Models for Bladed Disks With Mistuning and Varying Operational Speed
Authors: Kurstak Eric , Wilber Ryan , D'Souza Kiran
Published: August 2018

A considerable amount of research has been conducted to develop reduced order models (ROMs) of bladed disks that can be constructed using single sector calculations when there is mistuning present. A variety of methods have been developed to efficiently handle different types of mistuning ranging from small frequency mistuning, which can be modeled using a variety of methods including component mode mistuning (CMM), to large geometric mistuning, which can be modeled using multiple techniques including pristine rogue interface modal expansion (PRIME). Research has also been conducted on developing ROMs that can accommodate the variation of specific parameters in the reduced space; these models are referred to as parametric reduced order models (PROMs). This work introduces a PROM for bladed disks that allows for the variation of rotational speed in the reduced space. These PROMs are created by extracting information from sector models at three rotational speeds, and then the appropriate ROM is efficiently constructed in the reduced space at any other desired speed. This work integrates these new PROMs for bladed disks with two existing mistuning methods, CMM and PRIME, to illustrate how the method can be readily applied for a variety of mistuning methods. Frequencies and forced response calculations using these new PROMs are compared to the full order finite element calculations to demonstrate the effectiveness of the method.
Large Eddy Simulation of a Premixed Flame in Hot Vitiated Crossflow With Analytically Reduced Chemistry
Authors: Schulz Oliver , Noiray Nicolas
Published: August 2018

This numerical study deals with a premixed ethylene–air jet at 300 K injected into a hot vitiated crossflow at 1500 K and atmospheric pressure. The reactive jet in crossflow (RJICF) was simulated with compressible 3D large eddy simulations (LES) with an analytically reduced chemistry (ARC) mechanism and the dynamic thickened flame (DTF) model. ARC enables simulations of mixed combustion modes, such as autoignition and flame propagation, that are both present in this RJICF. 0D and 1D simulations provide a comparison with excellent agreement between ARC and detailed chemistry in terms of autoignition time and laminar flame speed. The effect of the DTF model on autoignition was investigated for varying species compositions and mesh sizes. Comparisons between LES and experiments are in good agreement for average velocity distributions and jet trajectories; LES remarkably capture experimentally observed flame dynamics. An analysis of the simulated RJICF shows that the leeward propagating flame has a stable flame root close to the jet exit. The lifted windward flame, on the contrary, is anchored in an intermittent fashion due to autoignition flame stabilization. The windward flame base convects downstream and is “brought back” by autoignition alternately. These autoignition events occur close to a thin layer that is associated with radical build-up and that stretches down to the jet exit.
Effect of Soybean Biodiesel Addition on Tribological Performance of Ultra-Low Sulfur Diesel
Authors: Alves Salete Martins , de Farias Aline Cristina Mendes , Mello Valdicleide Silva , Oliveira Junior José J.
Published: August 2018

The purpose of this work was to study the influence of soybean biodiesel addition in ultra-low sulfur diesel (ULSD) on its tribological behavior under low-amplitude reciprocating conditions, simulating the operation of a fuel injector system. The methodology was divided into three parts: the first was the fuel preparation and its physicochemical characterization, where were studied four fuels (diesel, soybean biodiesel, and mixtures of them).The following step was the evaluation of the fuel tribological properties, using the high-frequency reciprocating rig (HFRR) test. These tests were carried out by steel ball-on-disk lubricated contact, on which the friction coefficient of friction (COF), the film percentage, and the wear scar diameter (WSD) were measured, according to ASTM D6079-11. In the end, the analysis of the damages presented on the worn disk surfaces was characterized by scanning electronic microscopy (SEM) and atomic force microscopy (AFM) techniques. Results showed that the addition of biodiesel to ULSD is an excellent option to restore the lubricating ability of this fuel. The biodiesel incorporation reduces the friction coefficient and improves the film formation. Besides, the evaluation of worn disk surfaces using SEM and AFM techniques showed that biodiesel avoids damages to surface through protective film formation and reduces the superficial roughness.
Synthetic lethality with cisplatin
Authors: Ferrarelli Leslie K.
Published: August 2018

Blocking the kinase MAST1 with lestaurtinib prevents cisplatin resistance in cancers driven by Raf-MEK signaling.
IL-1 plays backup
Authors: Foley John F.
Published: August 2018

Signaling by the cytokine IL-1 provides a backup mechanism to maintain barrier defense during infection by immune-evasive viruses.
Reduced-Particle-Size Wheat Bran Is Efficiently Colonized by a Lactic Acid-Producing Community and Reduces Levels of Enterobacteriaceae in the Cecal Microbiota of Broilers
Authors: Vermeulen Karen , Verspreet Joran , Courtin Christophe M. , Haesebrouck Freddy , Baeyen Steve , Haegeman Annelies , Ducatelle Richard , Van Immerseel Filip
Published: August 2018

Prebiotic dietary fibers are known to improve the gastrointestinal health of both humans and animals in many different ways. They can increase the bulking capacity, improve transit times, and, depending on the fiber, even stimulate the growth and activity of resident beneficial bacteria. Wheat bran is a readily available by-product of flour processing and is a highly concentrated source of (in)soluble dietary fiber. The intake of fiber-rich diets has been associated with increased
Firmicutes
and decreased
Proteobacteria
numbers. Here, we show that applying only 1% of a relatively simple substrate which was technically modified using relatively simple techniques reduces the concentration of
Enterobacteriaceae
. This could imply that in future intervention studies, one should take the particle size of dietary fibers into account.
Characterization of the Widely Distributed Novel ECF42 Group of Extracytoplasmic Function σ Factors in Streptomyces venezuelae
Authors: Liu Qiang , Pinto Daniela , Mascher Thorsten
Published: August 2018

In contrast to the one- and two-component signal transduction systems in bacteria, the importance and diversity of ECFs have only recently been recognized in the course of comprehensive phylogenetic and comparative genomics studies. Thus, most of the ECFs still have not been experimentally characterized regarding their physiological functions and regulation mechanisms so far. The physiological roles, target promoter, and target regulons of a novel group of ECFs, ECF42, in
S. venezuelae
have been investigated in this work. More importantly, members of this group are characterized by a C-terminal extension, which has been verified to harbor a regulatory role in ECF42s. Hence, our work provides an important source for further research on such C-terminal extension containing ECFs.
Comparison of the ‘11+ Kids’ injury prevention programme and a regular warmup in children’s football (soccer): a cost effectiveness analysis
Authors: Rössler Roland , Verhagen Evert , Rommers Nikki , Dvorak Jiri , Junge Astrid , Lichtenstein Eric , Donath Lars , Faude Oliver
Published: August 2018

Objective

To evaluate a potential reduction in injury related healthcare costs when using the ‘11+ Kids’ injury prevention programme compared with a usual warmup in children’s football.

Methods

This cost effectiveness analysis was based on data collected in a cluster randomised controlled trial over one season from football teams (under-9 to under-13 age groups) in Switzerland. The intervention group (INT) replaced their usual warmup with ‘11+ Kids’, while the control group (CON) warmed up as usual. Injuries, healthcare resource use and football exposure (in hours) were collected prospectively. We calculated the mean injury related costs in Swiss Francs (CHF) per 1000 hours of football. We calculated the cost effectiveness (the direct net healthcare costs divided by the net health effects of the ‘11+ Kids’ intervention) based on the actual data in our study (trial based) and for a countrywide implementation scenario (model based).

Results

Costs per 1000 hours of exposure were CHF228.34 (95% CI 137.45, 335.77) in the INT group and CHF469.00 (95% CI 273.30, 691.11) in the CON group. The cost difference per 1000 hours of exposure was CHF−240.66 (95%CI −406.89, −74.32). A countrywide implementation would reduce healthcare costs in Switzerland by CHF1.48 million per year. 1002 players with a mean age of 10.9 (SD 1.2) years participated. During 76 373 hours of football, 99 injuries occurred.

Conclusion

The ‘11+ Kids’ programme reduced the healthcare costs by 51% and was dominant (ie, the INT group had lower costs and a lower injury risk) compared with a usual warmup. This provides a compelling case for widespread implementation.
The presence of companions during emergency department evaluation and its impact on perceptions of clinician–patient communication
Authors: Cornelius Talea , Moise Nathalie , Birk Jeffrey L , Edmondson Donald , Chang Bernard P
Published: August 2018

Objectives

Research in outpatient setting suggests that the presence of companions during a medical encounter can improve clinician–patient communication. It is not known if the presence of companions has a similar effect in the acutely stressful context of the ED. This study tested whether the presence of companions in the ED relate to stronger clinician–patient communication. We further explored effect modification by demographic factors (race/ethnicity, education and language) thought to compromise communication.

Methods

Participants were drawn from an observational cohort study of patients with suspected acute coronary syndrome (n=876) recruited from an urban academic medical centre between 2013 and 2016. Patient interviews occurred both in the ED and post-ED discharge; communication was assessed using the Interpersonal Processes of Care Survey with possible range of scores of 14–70. Companions were categorised as close others (ie, partner/spouse or child), non-close others (eg, neighbour) or no one.

Results

Perceptions of clinician–patient communication were high (mean=57.1,SD=10.6;). There was no association between companions (close/non-close/no one) and clinician–patient communication, p=0.262. Demographic factors were unrelated to communication. There was a significant interaction between education and companions. Having a close other in the ED was associated with stronger clinician–patient communication only for patients with high school education or less, p=0.027.

Conclusions

Neither the presence of companions nor demographic factors were related to clinician–patient communication. The interaction effect suggesting that patients completing high school or less have the most to gain from the presence of close others warrants further exploration.
Performance, carcass characteristics, and centesimal composition of meat from Santa Inês lambs and Texel crossbred lambs (Santa Inês × Texel)
Authors: Nunes Iolanda Aparecida , Brito Ricardo Alessandro Martins , de Morais Letícia Aparecida , Silva Vanessa Souza , da Silva Marco Antônio Pereira , do Carmo Ruthele Moraes
Published: August 2018

This study evaluated the performance, carcass characteristics, and centesimal composition of the meat of intact and castrated lambs of the Santa Inês breed and of the crossbred animals: one-half Santa Inês × one-half Texel. Thirty-four lambs were used, nine intact and nine castrated males of the Santa Inês breed, and seven intact and nine castrated crossbred males, all aged between 6 and 7 mo and with an average live weight of 18.2 kg. The design was completely randomized in a 2 × 2 factorial (two crossing and two sexual conditions), with statistical analyses performed in the STAT version 9.4 program. There was a significant difference the Santa Inês and the Texel and Santa Inês crossbred animals in feed conversion and average daily gain, with superiority of the latter group. Castration of animals aged <12 mo had no significant effect on the performance and on the carcass traits of the Texel and Santa Inês crossbred animals, whereas the genotype had a great influence on weight gain and on subjective and quantitative carcass characteristics, demonstrating that crosses in sheep are needed to explore the complementarity of breeds, and heterosis is needed to achieve better performances and carcass characteristics.
Effect of a single dose of subcutaneous meloxicam before knife castration alone or combined with hot-iron branding on scrotal healing, inflammatory response, and behaviour in 2-mo-old beef calves over 42 d post procedure
Authors: Marti S. , Meléndez D.M. , Pajor E.A. , Moya D. , Gellatly D. , Janzen E.D. , Schwartzkopf-Genswein K.S.
Published: August 2018

The objective of this study was to evaluate the effect of a single subcutaneous injection of meloxicam on scrotal healing, inflammatory response, and behaviour in castrated or castrated and branded beef calves for 42 d post procedure. Seventy-two 2-mo-old Angus crossbred bull calves were used to assess the effects of procedure (Trt): (1) sham control, (2) knife castration, and (3) knife castration and hot-iron branding; and pain mitigation (Med): (1) nonmedicated and (2) medicated with meloxicam according to a 3 × 2 factorial design. Body weight, scrotal circumference (SC), and healing scores were collected weekly until day 42. Blood samples were collected weekly until day 42 to assess haptoglobin, serum amyloid-A, and complete blood cell count. Hair was collected on day −1 and day 42 to assess cortisol concentrations. Lying and standing behaviour were recorded for 42 d, whereas pain-related behaviours were recorded on days 7, 15, 22, 29, and 34 post procedure. The inflammatory response (SC) and duration of standing was greater (P < 0.05) in calves castrated and branded than those only castrated. However, meloxicam did not reduce inflammation or improve wound healing in either castrated or castrated and branded calves.
Genome-wide identification, evolution, and expression analysis of theKT/HAK/KUPfamily in pear
Authors: Wang Yingzhen , Lü Jiahong , Chen Dan , Zhang Jun , Qi Kaijie , Cheng Rui , Zhang Huping , Zhang Shaoling
Published: August 2018

The K+transporter/high-affinity K+/K+uptake (KT/HAK/KUP) family, as one of the largest K+transporter families in higher plants, plays an essential role in plant growth, mineral element absorption, salt stress tolerance, and other physiological processes. However, little is known about this family in pear (Pyrus). Here, we identified 20 K+transporter genes in pear (P. bretschneideri) using genome-wide analysis. Their gene structure, chromosomal distribution, conserved motifs, phylogenetics, duplication events, and expression patterns were also examined. The results of phylogenetic analysis showed that PbrKT/HAK/KUP genes were clustered into three major groups (Groups I–III). Among the 20 PbrKT/HAK/KUP genes, 18 were mapped to nine chromosomes and two to scaffolds. Four WGD/segmental gene pairs were identified, indicating that WGD/segmental duplication may have contributed to the expansion of the KT/HAK/KUP family in pear. Among the four pairs of WGD/segmentally duplicated genes, both members of three pairs had been subjected to purifying selection, whereas the fourth pair had been subjected to positive selection. Furthermore, phenotypic experiments showed that the growth of pear seedlings was affected by potassium deficiency treatment. Expression patterns of 20 PbrKT/HAK/KUP genes in roots were further assayed with qRT-PCR. PbrHAK1 and PbrHAK12/16 were significantly expressed in response to K+deficiency, suggesting that these genes are crucial for K+uptake in pear, especially under the condition of K+starvation. Our results provide a foundation for further study on the function of KT/HAK/KUP genes in pear.
A lower limb exoskeleton based on recognition of lower limb walking intention
Authors: Cha Dowan , Kim Kab Il
Published: August 2018

Recognition of walking intention and assistance in the load-carrying driver’s walking capability are key challenging areas in lower limb exoskeletons. We present a lower limb exoskeleton called the unmanned technology research centre exoskeleton (UTRCEXO). It recognizes walking intention, including step initiation, step velocity (acceleration and deceleration), and step termination of drivers using only insole-type FSRs and three axis F/T sensors. UTRCEXO recognizes the driver’s intention of step initiation using insole-type FSRs and recognizes the intention of step velocity and step termination using three axis F/T sensors. UTRCEXO makes use of four DC motors, two at each knee and hip joint, to assist the driver. The the driver can carry a 20 kg payload comfortably with muscle activity reduction. In this paper, we evaluate muscle activity reduction in walking drivers equipped with UTRCEXO carrying a 20 kg payload.
Complementation of Branching Automata for Scattered and Countable N-Free Posets
Authors: Bedon Nicolas
Published: August 2018

We prove the effective closure under complementation of the class of languages of scattered and countable [Formula: see text]-free posets recognized by branching automata.
Aperiodic String Transducers
Authors: Dartois Luc , Jecker Ismaël , Reynier Pierre-Alain
Published: August 2018

Regular string-to-string functions enjoy a nice triple characterization through deterministic two-way transducers (2DFT), streaming string transducers (SST) and MSO definable functions. This result has recently been lifted to FO definable functions, with equivalent representations by means of aperiodic 2DFT and aperiodic 1-bounded SST, extending a well-known result on regular languages. In this paper, we give three direct transformations: [Formula: see text] from 1-bounded SST to 2DFT, [Formula: see text] from 2DFT to copyless SST, and [Formula: see text] from [Formula: see text]-bounded to [Formula: see text]-bounded SST. We give the complexity of each construction and also prove that they preserve the aperiodicity of transducers. As corollaries, we obtain that FO definable string-to-string functions are equivalent to SST whose transition monoid is finite and aperiodic, and to aperiodic copyless SST.
Degrees of Infinite Words, Polynomials and Atoms
Authors: Endrullis Jörg , Karhumäki Juhani , Klop Jan Willem , Saarela Aleksi
Published: August 2018

We study finite-state transducers and their power for transforming infinite words. Infinite sequences of symbols are of paramount importance in a wide range of fields, from formal languages to pure mathematics and physics. While finite automata for recognising and transforming languages are well-understood, very little is known about the power of automata to transform infinite words.

The word transformation realised by finite-state transducers gives rise to a complexity comparison of words and thereby induces equivalence classes, called (transducer) degrees, and a partial order on these degrees. The ensuing hierarchy of degrees is analogous to the recursion-theoretic degrees of unsolvability, also known as Turing degrees, where the transformational devices are Turing machines. However, as a complexity measure, Turing machines are too strong: they trivialise the classification problem by identifying all computable words. Finite-state transducers give rise to a much more fine-grained, discriminating hierarchy. In contrast to Turing degrees, hardly anything is known about transducer degrees, in spite of their naturality.

We use methods from linear algebra and analysis to show that there are infinitely many atoms in the transducer degrees, that is, minimal non-trivial degrees.
Square-Free Partial Words with Many Wildcards
Authors: Gasnikov Daniil , Shur Arseny M.
Published: August 2018

We contribute to the study of square-free words. The classical notion of a square-free word has a natural generalization to partial words, studied in several papers since 2008. We prove that the maximal density of wildcards in the ternary infinite square-free partial word is surprisingly big: [Formula: see text]. Further we show that the density of wildcards in a finitary infinite square-free partial words is at most [Formula: see text] and this bound is reached by a quaternary word. We demonstrate that partial square-free words can be viewed as “usual” square-free words with some letters replaced by wildcards and introduce the corresponding characteristic of infinite square-free words, called flexibility. The flexibility is estimated for some important words and classes of words; an interesting phenomenon is the existence of “rigid” square-free words, having no room for wildcards at all.
Search for vector-like quarks in a fermionic dark matter model with pseudoscalar: A resonance case
Authors: Ayazi Seyed Yaser , Mohamadnejad Ahmad , Zakeri S. Peyman
Published: August 2018

We propose a minimal model of a fermionic dark matter with a pseudoscalar mediator and N generation of vector-like quarks. We calculate the relic density and obtain a new constraint on the generation of the vector-like quarks. From the viewpoint of phenomenology, we probe the proposed model via direct and indirect approaches. Finally, as an illustrative example, we evaluate a resonance case — the subject of major experiments designed for detection of new particles. Our analysis results in significant constraints on the coupling strength of vector-like quarks.
Research on Management System of Automatic Driver Decision-Making Knowledge Base for Unmanned Vehicle
Authors: Zhang Zhaoxia , Jiang Qing , Wang Rujing , Song Liangtu , Zhang Zhengyong , Wei Yuanyuan , Mei Tao , Yu Biao
Published: August 2018

The acquisition, presentation and management of autonomous driving decision-making knowledge of unmanned vehicles are the key and difficult issues in the autonomous driving decision-making system of unmanned vehicles. This paper presents a knowledge model, which includes problem description layer and problem-solving knowledge layer. The automatic driving decision knowledge base of unmanned vehicle is composed of a set of knowledge models. Knowledge model supports knowledge representation and reasoning. Based on the WEB visualization knowledge modeling tool and visualization knowledge service tool, we construct the decision-making knowledge base management system for autonomous driving of unmanned vehicles and then construct the autonomous driving decision-making system of unmanned vehicles. The reasoning example shows that the knowledge base management system can effectively improve the knowledge acquisition, representation and maintenance efficiency of autonomous driving decision-making system, which is of great significance in enhancing the intelligence level of autonomous driving decision-making system.
Digital Estimation and Compensation of Analog Errors in Frequency-Interleaved ADCs
Authors: Song Jinpeng , Tian Shulin , Hu Yu-Hen , Ye Peng , Yang Kuojun , Guo Lianping , Wei Wentao
Published: August 2018

A novel digital compensation scheme for measuring, estimating and correcting linear weakly time-varying analog errors in frequency-interleaved analog-to-digital converters (FI-ADCs) is presented. This method features three important improvements over existing approaches: First, the Wigner–Ville distribution (WVD) is used to better estimate the nonstationary analog channel frequency response (ACFR) spectrum. Secondly, the estimated ACFR spectrum is approximated with a rational polynomial model using the [Formula: see text]-norm metric. The corresponding [Formula: see text]-norm minimization problem is solved using a primal-relaxed dual global optimization (PRD-GOP) method. Thirdly, the digital compensation circuitry is designed utilizing a preconditioned biconjugate gradient stabilized (BICGSTAB) algorithm that yields a computationally efficient solution. Numerical experimentations have been conducted and the outcomes validate the feasibility and superior performance of this proposed method.
Klein–Gordon field from the XXZ Heisenberg model
Authors: Bilski Jakub , Brahma Suddhasattwa , Marcianò Antonino , Mielczarek Jakub
Published: August 2018

We examine the recently introduced idea of Spin-Field Correspondence (SFC) focusing on the example of the spin system described by the XXZ Heisenberg model with external magnetic field. The Hamiltonian of the resulting nonlinear scalar field theory is derived for arbitrary value of the anisotropy parameter [Formula: see text]. We show that the linear scalar field theory is reconstructed in the large spin limit. For [Formula: see text], a nonrelativistic scalar field theory satisfying the Born reciprocity principle is recovered. As expected, for the vanishing anisotropy parameter [Formula: see text], the standard relativistic Klein–Gordon field is obtained. Various aspects of the obtained class of the scalar fields are studied, including the fate of the relativistic symmetries and the properties of the emerging interaction terms. We show that, in a certain limit, the so-called polymer quantization of the field variables is recovered. This and other discussed properties suggest a possible relevance of the considered framework in the context of quantum gravity.
Improved Adaptive Particle Swarm Optimization for Optimization Functions and Clustering Fuzzy Modeling System
Authors: Houcine Lassad , Bouzbida Mohamed , Chaari Abdelkader
Published: August 2018

In this paper, a new PSO algorithm with a new adaptive weight of inertia and time acceleration coefficients (TVAC) is proposed; this algorithm called IAPSO is introduced for global optimization. The objective of this proposition is to initialize the weight of inertia to a high value, giving priority to the global exploration of the research space and gradually decreasing the new inertia adaptable to the weight in order to obtain refined solutions. The test of our algorithm is performed on three standard reference functions (Schwefel’s (unimodal), Ackley (multimodal) and Griewank (Multimodal)). The proposed IAPSO algorithm combined with the Fuzzy Clustering NPCM algorithm for modeling and identifying a non-linear system. The new NPCM-IAPSO grouping algorithm also solves the problems of the classical clustering algorithm (FCM, GK, PCM, EPCM, FCM-PSO, EPCM-PSO …etc.), such as convergence towards local optimization and sensitivity to initialization. The effectiveness of the proposed NPCM-IAPSO algorithm was tested on the furnace gas Box and Jenkins, dryer system and two other nonlinear systems described by differential equations.
A Stock Market Prediction System Based on High-Level Fuzzy Petri Nets
Authors: Shen Rong-Kuan , Yang Cheng-Ying , Shen Victor R. L. , Li Wei-Chen , Chen Tzer-Shyong
Published: August 2018

As information technology advances dramatically and the stock market in Taiwan turns out to be active, the management of financial investment has already become very important. To facilitate the rapid development of the stock market, the application of information technology to financial investment becomes a hot issue. In this paper, a support vector regression (SVR) machine for stock prices in Taiwan is adopted to simulate the approximate trading trend by using the daily data sets. Then the learned data model is used to analyze technical indices, to draw a trend diagram, and to make a prediction. Finally, the business behavior of financial investment systems has been modeled by using a high-level fuzzy Petri net (HLFPN) for the purpose of making a decision on appropriate investment. Based on the HLFPN model, the proposed approach provides each investor with relevant information to understand the investment trend. As a result, a practical market stock prediction system is presented to enhance the investment benefits and help investors achieve the desired investment goal.
On-Line Fault-Tolerant Fuzzy-Based Path Planning and Obstacles Avoidance Approach for Manipulator Robots
Authors: Maoudj Abderraouf , Hentout Abdelfetah , Bouzouia Brahim , Toumi Redouane
Published: August 2018

Manipulator robots are widely used in many fields to replace humans in complex and risky environments. However, in some particular environments the robot is prone to failure, resulting in decreased performance. In such environments, it is extremely difficult to repair the robot which interrupts the execution process. Therefore, fault tolerance plays an important role in industrial manipulators applications. In this paper, the key problems related to fault-tolerance and path planning of manipulator robots under joints failures are handled within an on-line fault-tolerant fuzzy-logic based path planning approach for high degree-of-freedom robots. This approach provides an alternative to using mathematical models to control such robots, and improves tolerance to certain faults and mechanical failures. The controller consists of two fuzzy units (i) the first unit, Fuzzy_Path_Planner, is responsible of path planning; (ii) the second unit, Fuzzy_Obstacle_Avoidance, is conceived for obstacles avoidance. Moreover, the proposed approach is capable of repelling the manipulator away from both local minima and limit cycle problems. Finally, to validate the proposed approach and show its performances and effectiveness, different tests are carried out on two six degree-of-freedom manipulator robots (ULM and PUMA560 robots), accomplishing point-to-point tasks, with and without considering some joints failures.