bluuebunny/crossref_metadata_2025 huggingface dataset:
Automated High Level Process Planning for Agile Manufacturing
Authors: Gupta S. , Herrmann J. W. , Lam G. , Minis I.
Published: March 2021

Agile manufacturing combines the strengths of qualified partners in a virtual organization to meet a certain market need. High level process planning is a way to aid designers to improve their design with respect to the capabilities of potential partners. An automated high level process planning system for mechanical components has been developed which considers both global and partner-specific manufacturing capabilities so that cost, cycle time, and quality attributes can be derived for a given design. The system generates a set of manufacturing operations and candidate partner plants that can contribute to the manufacture of the candidate design. The most promising process plans resulting from this process may be used be used to select the most suitable partners for the virtual enterprise.
The Development of a Real Time Recursive Frequency Based Active Chatter Controller
Authors: Kim Sun , Ousterhout Karl B.
Published: March 2021

In most machining processes, large amounts of energy are needed to accomplish the machining operation. When this energy is transmitted through a structure that has minimal damping characteristics, such as a lathe or a milling machine, self sustained oscillations (chatter) can develop. When chatter develops, it can be viewed as a basic performance limitation of the machine tool. In order to suppress the chatter, a real-time controller using digital signal processing techniques has been implemented. This paper discusses a novel method for the real time computation of the transfer function of the machine tool-workpiece combination and illustrates how a real-time active chatter controller can be designed and integrated into existing machine tools to overcome this performance limitation.
Parametric Resonances of a Cantilevered Pipe Conveying Fluid: A Nonlinear Analysis
Authors: Semler C. , Païdoussis M. P.
Published: March 2021

This paper deals with the nonlinear dynamics and the stability of cantilevered pipes conveying fluid, where the fluid has a harmonic component of flow velocity, assumed to be small, superposed on a constant mean value. The mean flow velocity is near the critical value for which the pipe becomes unstable by flutter through a Hopf bifurcation. The partial differential equation is transformed into a set of ordinary differential equations (ODEs) using the Galerkin method. The equations of motion contain nonlinear inertial terms, and hence cannot be put into standard form for numerical integration. Various approaches are adopted to tackle the problem: (a) a perturbation method via which the nonlinear inertial terms are removed by finding an equivalent term using the linear equation; the system is then put into first-order form and integrated using a Runge-Kutta scheme; (b) a finite difference method based on Houbolt’s scheme, which leads to a set of nonlinear algebraic equations that is solved with a Newton-Raphson approach; (c) the stability boundaries are obtained using an incremental harmonic balance method as proposed by S.L. Lau. Using the three methods, the dynamics of the pipe conveying fluid is investigated in detail. For example, the effects of (i) the forcing frequency, (ii) the perturbation amplitude, and (iii) the flow velocity are considered. Particular attention is paid to the effects of the nonlinear terms. These results are compared with experiments undertaken in our laboratory, utilizing elastomer pipes conveying water. The pulsating component of the flow is generated by a plunger pump, and the motions are monitored by a noncontacting optical follower system. It is shown, both numerically and experimentally, that periodic and quasiperiodic oscillations can exist, depending on the parameters.
On the Analysis of Time-Periodic Nonlinear Hamiltonian Dynamical Systems
Authors: Butcher Eric A. , Sinha S. C.
Published: March 2021

In this paper, some analysis techniques for general time-periodic nonlinear Hamiltonian dynamical systems have been presented. Unlike the traditional perturbation or averaging methods, these techniques are applicable to systems whose Hamiltonians contain ‘strong’ parametric excitation terms. First, the well-known Liapunov-Floquet (L-F) transformation is utilized to convert the time-periodic dynamical system to a form in which the linear pan is time invariant. At this stage two viable alternatives are suggested. In the first approach, the resulting dynamical system is transformed to a Hamiltonian normal form through an application of permutation matrices. It is demonstrated that this approach is simple and straightforward as opposed to the traditional methods where a complicated set of algebraic manipulations are required. Since these operations yield Hamiltonians whose quadratic parts are integrable and time-invariant, further analysis can be carried out by the application of action-angle coordinate transformation and Hamiltonian perturbation theory.

In the second approach, the resulting quasilinear time-periodic system (with a time-invariant linear part) is directly analyzed via time-dependent normal form theory. In many instances, the system can be analyzed via time-independent normal form theory or by the method of averaging. Examples of a nonlinear Mathieu’s equation and coupled nonlinear Mathieu’s equations are included and some preliminary results are presented.
Nonlinear Structural Damping Described by the Masing Model and the Method of Slowly Varying Amplitude and Phase
Authors: Gutzer Ulrich , Seemann Wolfgang , Hagedorn Peter
Published: March 2021

In this paper we investigate vibrations of discrete and continuous systems with damping of the MASING type. For free vibrations the method of the slowly varying amplitude and phase shows good agreement with numerical results, especially if the damping is small. The equations resulting from this method allow a faster identification of the parameters of a physical model. First, a single degree of freedom system is studied. Explicit formulae are obtained for the changing amplitude and frequency. The results are useful since damping laws of the type under consideration are well suited to describe the energy dissipation in a variety of real structures. In the second part we consider a one dimensional continuum with a distributed MASING model. An explicit formula is found for the dissipated energy per cycle and wavelength in standing waves.
Chaos of Nonlinear Vibratory System With Single Well Potential
Authors: Zhang Wei
Published: March 2021

In this paper we study chaotic dynamics of nonlinear vibratory system under combined parametric and forcing excitations with single well potential. Especially we focus on chaos of a centrifugal pendulum vibration absorber. The centrifugal pendulum vibration absorber is an efficient device that is used to reduce torsional vibration in crank shaft of internal combustion engine. Because reduced dynamical model of the centrifugal pendulum vibration absorber is a nonlinear system, there is very rich dynamical behavior in this system. We use Meknikov’s method and numerical method to study chaotic dynamics of the centrifugal pendulum vibration absorber and discuss the route from bifurcations of T2 torus to chaotic motion.
Experimental Correlation of Dynamic Finite Element Models
Authors: Martin Raymond E. , O’Brien David M.
Published: March 2021

Finite element models used in the dynamic analysis of structures benefit from correlation with experimental data at each step in the analytical development. The steps Aircraft Landing Systems has followed in obtaining both modal and operational data for the validation of aircraft wheel, brake, and strut FEA models are discussed in this paper. These steps include the creation of a valid experimental modal model for major components in the structure, correlation of the modal results to tie FE model results, testing of sub-assemblies, and collecting data from dynamometer tests of the system and their correlation to the assembled FE model of the system. Various procedures are described which have been developed and adapted by Aircraft Landing Systems and which enable practical correlation to frequencies as high as 2000 Hz. The application of the procedures are demonstrated with examples from recent testing.
Optimal Windows for the Time-Frequency Analysis of Arbitrary Swept Frequency Signals
Authors: Mooney James A. , Soom Andres
Published: March 2021

In noise and vibration analysis, as well as in many other engineering applications, it may be necessary to extract or analyze signals with time-varying frequency components. Examples include start-up and shut-down of rotating machinery, transient structural vibrations, vehicle passing noise, and speech analysis. Both Short-Time Fourier Transforms (STFT), representing a set of non-causal filters of constant bandwidth, and Wavelet Transforms, representing a set of non-causal filters of constant Q or constant percent bandwidth, have been used for such Joint Time Frequency Analysis (JTFA). In the present work, an arbitrary swept frequency signal is approximated locally, in time, by a linearized frequency sweep. We show that an optimal time window can be identified which, at a given frequency, is inversely proportional to the square root of the instantaneous rate of change of frequency. We find that the constant bandwidth of the STFT and the constant-Q of the Wavelet transform represent extreme cases which are each optimal for certain types of signals. In between the two extremes there lies a continuous range of variation of the effective bandwidth with frequency. Many important types of signals require analysis window variation in this range between STFT and Wavelet analysis. The paper concludes with some simple rules for optimizing the variation of the analysis window with frequency for various types of signals.
A Coupling of FEM-BEM for Elastic Structure in a Transient Acoustic Field
Authors: Filipe M. , Ha-Duong T.
Published: March 2021

We propose in this paper a space-time variational formulation for the scattering problem of transient acoustic waves in a fluid medium with a submerged elastic object. The problem is first reduced to a coupling problem between partial differential equations and boundary integral equations and an energy formula given in terms of the unknowns of this coupling problem. The variational formulation follows then. A space-time finite element method based on this formulation gives rise to a time-stepping scheme with both volume and surface spatial elements as variables.
Studies of Acoustic Characteristics and Their Comparison With Vibration Ones
Authors: Ekimov Alexander E.
Published: March 2021

The present paper gives the methods, schemes and results of experiments based on direct and reciprocal methods of measurements. The use of the reciprocity method made it possible to solve the problem of determining the acoustic characteristics of the distributed system model where vibroactive sources are represented in the form of passive models. It has been shown that the normalized transfer coefficient characterizing a link between force and acoustic fields has the same value both for the model and in nature (in case of their full similarity) that can be used:

- to improve the methods of designing and technological manufacturing of models based on the comparison of normalized transfer coefficients obtained for full-scale and physical models;

- to forecast the acoustic radiation of some vibroactive mechanisms using the assigned force characteristics and normalized transfer coefficients obtained for a model with the modelling scale taken into account.
Resonance Low Frequency Sound Source With Extended Frequency Band
Authors: Donskoy Dimitri M. , Nazalewicz Jan
Published: March 2021

A new concept of a low-frequency (< 1000-Hz) underwater sound source has been proposed and tested (Donskoy and Blue, 1994). The present work is a further development of the source. A full scale reaction force driver to power the source was developed, built, and tested. In order to extend frequency band of the source, a double resonance approach (resonating reaction mass and resonating radiation piston) was employed. This approach allows for a significant extension (up to 400%) of the frequency band without an increase in a vibromotive force.

The driver consists of a brushless servomotor, a brushless resolver for feedback, a Digital Signal Processor (DSP) based servo amplifier, and an interface with a PC. Vibromotive force is created with an eccentric weight mounted to a resonating mechanical structure. The driver can generate up to 8.000 lbs force, it has a programmable frequency control in the range up to 117 Hz, high power output (3.3 kW), compact size, low weight, and relatively low cost.
Acoustic Shape Optimization Using Parametric Finite Elements
Authors: Huff John E. , Bernhard Robert J.
Published: March 2021

A procedure for shape optimization of acoustic enclosures using parametric finite elements is presented. Use of this method facilitates both design sensitivity calculations and the automation of the optimization process. The parametric finite elements can also be used to achieve a reduction of the computational cost of finding the optimal solution for a design problem. The method is verified using a model of a one dimensional, driven acoustic duct. The optimization technique is then applied to a sample problem of the reduction of the sound pressure level inside a two dimensional model of an automobile interior. The optimization is done for both a single frequency and a frequency band. The novel aspects of the use of parametrically defined finite elements and the merits of the method are discussed.
Structural Acoustic Design
Authors: Nicolas Jean , Atalla Noureddine , Foin Olivier , Berry Alain
Published: March 2021

Nowadays, acoustic quietening of manufactured products is gaining importance. Due to cost, severe weight and operational constraints, classical noise control techniques, although still usable, are becoming less attractive. Nowadays, engineers follow essentially two major approaches (i) reduce noise by passive means, design modifications of structures and systems (ii) reduce noise by active sound and vibration control. This paper is devoted to the structural acoustic design approach for which there are either some simple rules of thumb either huge numerical codes. The main objective of this paper is to bridge the gap between these two extremes.

For the vibration response, the approach is based on a variational method. The basic structure is a plate with several degrees of complexity: added local or distributed masses, added local or distributed stiffeners, added stiffeners, added damping and constrained layer damping, force and moment type of excitations. The general trend has been to model an equivalent plate with two objectives in mind: (i) numerical calculations may be performed on a P.C., (ii) results are as close as possible to the exact solution.

For the acoustic radiation, a novel approach has been used based on Berry’s idea (Berry, 1994) to develop the Green function in terms of a Taylor expansion. Analytical impedance functions may then be calculated for various aspect ratios and then extracted directly from files which allow considerable atime gains over any other rigorous approaches.

The A.D.N.R. (Acoustic Design Noise Reduction) code has been validated through several experimental steps and agreement is revealed to be quite good. Not only is A.D.N.R. precise, but it also covers a wide frequency range (low, medium and high frequencies) which is really an advantage.

The output data are diversified and among them we may cite: modal shape, operating deflection shape, quadratic velocity, radiation factor and overall sound power.

In practice, A.D.N.R. revealed itself to be a great tool at the pre-design stage, when clear and quick trends are needed.
Substructuring: Definition of the Analytical Dynamic Model of a Complex System During its Design Stage
Authors: Llorca Fabrice , Gerard Alain , Hennequin Denis , Brenot Dominique
Published: March 2021

A structure is often an assembly of several components coupled by various joints such as bolted or riveted joints. Component mode synthesis methods are very practical tools to define a dynamic model. But, several points have to be examined and improved in order to give a complet representation of the modal behaviour of the whole structure.

For example, rotational degrees of freedom on connecting points between adjacent substructures should be estimated to give a better representation of the multidirectional connecting forces. These informations may be evaluated through a method based on both interpolation and spatial derivation of the experimental translational displacements of the components.

Unlike many other structural elements, the dynamic properties of a connection are very difficult to evaluate. So, we propose a method of determining joint stiffness characteristics. We consider only the conservative problem so the damping properties of the different components of the considered assembly are not taken into account. The joint characteristics are extracted comparing experimental modal data base and component mode synthesis simulation. The updating procedure is based on a nonlinear iterative least-square method. Results are presented concerning a particular assemblie of rectangular plates. Structural modification is applied for one component. We show that the joint properties stay the same if the connecting interface is not modified. The close correlation between predicted and experimental results demonstrate that this method is well adaptated to the study of structural modifications.
A Comparative Study on the Monitoring and Diagnostics of Machinery Gear Systems
Authors: El-Karmalawy Moataz , Ganesan R. , Sankar T. S.
Published: March 2021

The efficiency and suitability of on-line vibration measurements as a diagnostic signal for condition monitoring and diagnostics of gear systems, are investigated. To this end, representation of a gear system as a single-degree-of-freedom dynamic system is considered. Mathematical models of faults or malfunctions of the gear system for use in the above dynamic system as its system and excitation parameters are synthesized. Further, the sensitivities of vibration signal parameters including time-domain, frequency domain and statistical parameters, to various different faults or malfunctions are identified and explained. Based on this information, the rational basis of using on-line vibration signal parameters as the diagnostic indices of a gear system is established. Experimental results are obtained from real-life gear testers that have different types of faults or malfunctions. On-line vibration signals obtained from these gears tests are analyzed for time-domain, frequency domain, quefrency domain, statistical and time series model parameters. The efficiency and performance levels of each of these indices in diagnosing a particular type of fault are demonstrated. Reliable signal parameters corresponding to various types of faults or malfunctions in the gear system, that serve as best indications of damage development, are identified from the test results. Theoretical predictions and experimental observations of various types of gear system failures are compared in order to establish the confidence levels about the on-line vibration signal parameters.
Identification of Frequency Response Functions and Modal Data From Base Excitation Tests Using Measured Interface Forces
Authors: Schedlinski Carsten , Link Michael
Published: March 2021

Base excitation testing is used in industry in order to qualify mechanical systems with respect to specified base acceleration levels. This type of excitation only allows to identify eigenfrequencies, mode shapes and modal damping values of the fixed/free system. Modal masses, mass participation factors and effective masses of the fixed/free system as well as the modal data of the free/free system cannot be identified because the excitation forces are unknown.

This paper introduces an approach to identify these modal data as well. For this purpose the reaction forces at the table/structure interface have to be measured also. Furthermore, the verification of the theory using a laboratory test structure will be presented.
Active Vibration Quenching Using Inverse Dynamics
Authors: Trautt Thomas A. , Bayo Eduardo
Published: March 2021

An inverse dynamics algorithm is derived for active vibration quenching of structures. The algorithm uses frequency domain technicques to compute an input function needed to produce a desired response at a particular degree of freedom. The desired response is a transition from the initial vibrating condition to a non-vibrating condition. The algorithm can also be used to modify the input function to correct for system disturbances while the input function is already being applied to the system.

The algorithm is demostrated in a simulation of a simply supported beam controlled by a torque actuator at one end of the beam. The finite element method is used to discretize the equations of motion of the beam.
Vibration Control of Moving Flexible Structure by Repetitive Control
Authors: Mitsuta Shinji , Tsuji Hideki , Itoh Hiroyuki , Ogasawara Yasushi , Seto Kazuto
Published: March 2021

The purpose of this study is to move a flexible structure, such as conveyance equipment that moves periodically, quickly and accurately by controlling its vibration. In order to reduce the vibration of a flexible structure actively, a hydraulic actuator is arranged on the motion transmission path between a drive system and a flexible structure. Generally, it is possible to obtain good effects for reducing a residual vibration by using feedback control. However, the vibration displacement in motion is mainly forced vibration which is caused by motion acceleration, so it is difficult to reduce the vibration displacement by using feedback control. Thus, by considering that the flexible structure is driven periodically, we use the repetitive control method to reduce the vibration displacement in motion. In this study, the repetitive control method with the step response, which does not need model identification, is shown. Furthermore, the validity of this method is examined by simulation and experiment.
The Treatment of Systematic Errors in Model Updating
Authors: Friswell Michael I. , Mottershead John E. , Zhang Youhe
Published: March 2021

In the standard methods, accurate parameter estimates in finite element model updating rely on the model being fully converged in the frequency range of interest. In this paper a method is presented for the estimation of natural frequency discretisation errors in finite element models. The discretisation error is added to the measured data and is shown to reduce the bias in the resulting parameters estimates. The method is demonstrated using a bar and a beam example.
NIH apologizes for ‘structural racism,’ pledges change
Authors: Kaiser Jocelyn
Published: March 2021

Activists fault agency for not directly addressing funding disparity between white and Black grant applicants.
High-Throughput Screen for Inhibitors of the Type IV Pilus Assembly ATPase PilB
Authors: Dye Keane J. , Vogelaar Nancy J. , Sobrado Pablo , Yang Zhaomin
Published: March 2021

Many bacterial pathogens use their type IV pili (T4P) to facilitate and maintain infection of a human host. Small chemical compounds that inhibit the production or assembly of T4P have promise in the treatment and prevention of infections, especially in the era of increasing threats from antibiotic-resistant bacteria.
A Fault Prediction and Cause Identification Approach in Complex Industrial Processes Based on Deep Learning
Authors: Li Yao
Published: March 2021

Faults occurring in the production line can cause many losses. Predicting the fault events before they occur or identifying the causes can effectively reduce such losses. A modern production line can provide enough data to solve the problem. However, in the face of complex industrial processes, this problem will become very difficult depending on traditional methods. In this paper, we propose a new approach based on a deep learning (DL) algorithm to solve the problem. First, we regard these process data as a spatial sequence according to the production process, which is different from traditional time series data. Second, we improve the long short‐term memory (LSTM) neural network in an encoder‐decoder model to adapt to the branch structure, corresponding to the spatial sequence. Meanwhile, an attention mechanism (AM) algorithm is used in fault detection and cause identification. Third, instead of traditional biclassification, the output is defined as a sequence of fault types. The approach proposed in this article has two advantages. On the one hand, treating data as a spatial sequence rather than a time sequence can overcome multidimensional problems and improve prediction accuracy. On the other hand, in the trained neural network, the weight vectors generated by the AM algorithm can represent the correlation between faults and the input data. This correlation can help engineers identify the cause of faults. The proposed approach is compared with some well‐developed fault diagnosing methods in the Tennessee Eastman process. Experimental results show that the approach has higher prediction accuracy, and the weight vector can accurately label the factors that cause faults.
IMA genome - F14
Authors: van der Nest Magriet A. , Chávez Renato , De Vos Lieschen , Duong Tuan A. , Gil-Durán Carlos , Ferreira Maria Alves , Lane Frances A. , Levicán Gloria , Santana Quentin C. , Steenkamp Emma T. , Suzuki Hiroyuki , Tello Mario , Rakoma Jostina R. , Vaca Inmaculada , Valdés Natalia , Wilken P. Markus , Wingfield Michael J. , Wingfield Brenda D.
Published: March 2021

Draft genomes of Penicillium roqueforti, Fusarium sororula, Chalaropsis populi, and Chrysoporthe puriensis are presented. Penicillium roqueforti is a model fungus for genetics, physiological and metabolic studies, as well as for biotechnological applications. Fusarium sororula and Chrysoporthe puriensis are important tree pathogens, and Chalaropsis populi is a soil-borne root-pathogen. The genome sequences presented here thus contribute towards a better understanding of both the pathogenicity and biotechnological potential of these species.
A concerted probiotic activity to inhibit periodontitis-associated bacteria
Authors: Jansen Paul Mathias , Abdelbary Mohamed M. H. , Conrads Georg
Published: March 2021

Periodontitis can result in tooth loss and the associated chronic inflammation can provoke several severe systemic health risks. Adjunctive to mechanical treatment of periodontitis and as alternatives to antibiotics, the use of probiotic bacteria was suggested. In this study, the inhibitory effect of the probiotic Streptococcus salivarius subsp. salivarius strains M18 and K12, Streptococcus oralis subsp. dentisani 7746, and Lactobacillus reuteri ATCC PTA 5289 on anaerobic periodontal bacteria and Aggregatibacter actinomycetemcomitans was tested. Rarely included in other studies, we also quantified the inverse effect of pathogens on probiotic growth. Probiotics and periodontal pathogens were co-incubated anaerobically in a mixture of autoclaved saliva and brain heart infusion broth. The resulting genome numbers of the pathogens and of the probiotics were measured by quantitative real-time PCR. Mixtures of the streptococcal probiotics were also used to determine their synergistic, additive, or antagonistic effects. The overall best inhibitor of the periodontal pathogens was L. reuteri ATCC PTA 5289, but the effect is coenzyme B12-, anaerobiosis-, as well as glycerol-dependent, and further modulated by L. reuteri strain DSM 17938. Notably, in absence of glycerol, the pathogen-inhibitory effect could even turn into a growth spurt. Among the streptococci tested, S. salivarius M18 had the most constant inhibitory potential against all pathogens, followed by K12 and S. dentisani 7746, with the latter still having significant inhibitory effects on P. intermedia and A. actinomycetemcomitans. Overall, mixtures of the streptococcal probiotics did inhibit the growth of the pathogens equally or–in the case of A. actinomycetemcomitans- better than the individual strains. P. gingivalis and F. nucleatum were best inhibited by pure cultures of S. salivarius K12 or S. salivarius M18, respectively. Testing inverse effects, the growth of S. salivarius M18 was enhanced when incubated with the periodontal pathogens minus/plus other probiotics. In contrast, S. oralis subsp. dentisani 7746 was not much influenced by the pathogens. Instead, it was significantly inhibited by the presence of other streptococcal probiotics. In conclusion, despite some natural limits such as persistence, the full potential for probiotic treatment is by far not utilized yet. Especially, further exploring concerted activity by combining synergistic strains, together with the application of oral prebiotics and essential supplements and conditions, is mandatory.
Investigation of Stability Limits of a Premixed Counter Flame
Authors: Abdul Wahhab H.A.
Published: March 2021

In combustion operations, flame fronts are often spread in an irregular. Therefore, the temperature and flame speed varies along the flame's front and depend on the asymmetry of the composition of the mixture and the conditions of the local flow before the flame, especially this behavior is evident in double counter flames. This paper describes an analytical study of stability limits of premixed counter flame. The investigation is based on experiments carried out to identify the effect of varying the distance between upper and lower burner edges on the stability limits at different equivalence ratio values; liquid petroleum gas (LPG) was used as fuel in experiments. The blow-off limit, disc flame limit, and double flame limit were investigated. Under the change of fuel gas-air flow velocity, in this type of flames, the conical flame is transformed into mushroom-shaped tented flame attached to the widened convex apex in the medial distance between the upper and lower burner edges. The experimental data and numerical analysis obtained show that high-stability for double flame, fuel-rich premixed flame operate over narrow range of equivalence ratio φ from 0.43 to 1.41. The ANSYS 17.0 FLUENT Premixed Flamelet Module with pre-processing was used. The results appear that increasing distance between burner edges decreases the flame stability efficiency.
COVID-19 Outbreak Effects on Leadership, Job Satisfaction and Turnover Intention: A Mediating Model of Indonesian Banking Sector
Authors: Hidayat Tedi , Fahmy Rahmi , Sari Dessy Kurnia , Mergeresa Fineke , Fernando Yudi
Published: March 2021

This peper aims to determine and analyze the direct effect of transformational and transactional leadership on turnover intention, and indirect effect which is mediated by job satisfaction amid COVID 19 Pandemic at the banking sector. As many 153 permanent employees, including staff, supervisors, ass. manager, and division manager were participated. The results showed that transformational leadership has a positive but insignificant effect on turnover intention, while transactional leadership has a negative and significant affect turnover Intention. Furthermore, through mediating impact of job satisfaction, the effect of transformational leadership became negative and significant on turnover intention. Meanwhile, job satisfaction was significantly in line and strengthens the effect of transactional leadership on turnover intention at the banking sector amid COVID 19 Pandemic.
Comparison of Lipid Components, Iron and Zinc Levels in Chicken and Quail Eggs Available on the Market
Authors: Czerwonka Małgorzata , Białek Agnieszka , Skrajnowska Dorota , Bobrowska-Korczak Barbara
Published: March 2021

All over the world birds’ eggs are an important and valuable component of the human diet. The study aimed to compare the content of lipid components and their nutritional value as well as iron and zinc levels in chicken and quail eggs commonly available on the market. In egg lipids, unsaturated acids were dominated, especially oleic acid, the content of which was about 40% of total fatty acids (TFA). Linoleic acid was the major polyunsaturated fatty acid. Compared to other products of animal origin, eggs were characterized by favourable values of lipid quality indices, especially index of atherogenicity, thrombogenicity and hypocholesterolemic to hypercholesterolemic ratio. In the present study, no differences in the content of tested nutrients between eggs from different production methods (organic, free-range, barn, cages), as well as inter-breed differences were noticed. Cluster analysis showed that eggs enriched in n3 PUFA (according to producers’ declaration) differ from other groups of chicken eggs. However, only in eggs from one producer, the amount of EPA and DHA exceed 80 mg per 100 g, entitling to use the nutrition claim on the package. Quail eggs differed from chicken eggs in FA profile; they also had much higher iron and cholesterol levels.
Aymara Communities in the Lluta River Basin and Precordillera of the Arica and Parinacota Region: Agricultural Activities and Economic Projections
Authors: Sepúlveda-Chavera Germán , Muñoz Iván , Cifuentes Denise , Muñoz Patricio
Published: March 2021

The Region of Arica and Parinacota is characterized as an agricultural region located in Atacama Desert at the extreme north of Chile. Its agriculture has allow developing the economy of pre- and post-Hispanic communities, which have been settled since colonial times at different locations in the region. This article is focused on how Aymara communities of Lluta Valley and Precordillera of Arica and Parinacota Region have been included as part of Chilean population, particularly, from social and economic point of view. Furthermore, a characterization of agronomic aspects of the main towns of this zone, and commercialization of agricultural and livestock is included. It must be considered that the evolution of this region would have an important impact in the safeguard on endemic flora and fauna so that it is imperative to protect the genetic heritage of local species and to promote new technologies which allow the production of commercial products from Arica and Parinacota Region.
Comparison of Different Convolutional Neural Network Activation Functions and Methods for Building Ensembles
Authors: Nanni Loris , Brahnam Sheryl , Paci Michelangelo , Maguolo Gianluca
Published: March 2021

Recently, much attention has been devoted to finding highly efficient and powerful activation functions for CNN layers. Because activation functions inject different nonlinearities between layers that affect performance, varying them is one method for building robust ensembles of CNNs. The objective of this study is to examine the performance of CNN ensembles made with different activation functions, including six new ones presented here: 2D Mexican ReLU, TanELU, MeLU+GaLU, Symmetric MeLU, Symmetric GaLU, and Flexible MeLU. The highest performing ensemble was built with CNNs having different activation layers that randomly replaced the standard ReLU. A comprehensive evaluation of the proposed approach was conducted across fifteen biomedical data sets representing various classification tasks. The proposed method was tested on two basic CNN architectures: Vgg16 and ResNet50. Results demonstrate the superiority in performance of this approach. The MATLAB source code for this study will be available at https://github.com/LorisNanni.
Experimental melt inclusion homogenization in a hydrothermal diamond-anvil cell: Comparison with homogenization at one atmosphere
Authors: Li Shenghu , Li Jiankang , Chou I-Ming
Published: March 2021

Melt inclusion (MI) homogenization experiments are essential for determining the pressure-volume-temperature-composition (P-V-T-X) parameters of magma systems. The hydrothermal diamond-anvil cell (HDAC) is currently the only equipment that can exert external pressure on MIs while allowing in situ observation of MI phase changes during heating. The HDAC’s pressure potentially prevents the MI diffusion that, under heating at one atmosphere, produces artificially elevated measurements of phase transition temperatures. It is important to compare the phase transition temperatures measured using HDAC at elevated external pressure with those obtained using conventional equipment at one atmosphere. Such a comparison not only helps assess the reliability of HDAC phase transition temperatures but also helps determine phase transition temperatures that are naturally occurring in MI during the natural history of cooling.

In this study, we homogenized MIs hosted in quartz from the granitic porphyry in the Yixingzhai Au deposit, China, using HDAC at an elevated pressure of ~(140–230) MPa. We compared our experimental results with published data measured using a Linkam TS1500 stage at one atmosphere. The experiments show that the initial melting temperature (TIniM), total melting temperature (TTotM), and total homogenization temperature (ThTot) of the MIs are 695 ± 20, 780 ± 15, and 833 ± 17 °C, respectively. These phase transition temperatures are as much as 374 °C lower than the corresponding values measured at one atmosphere using the Linkam stage. Moreover, the temperatures measured using HDAC agree with actual values estimated using the linear extrapolation method based on correlations of MI size with phase transition temperatures measured using the Linkam stage. Based on the experimental HDAC results, we estimate that MIs in the Yixingzhai Au deposit were trapped at ~140 Ma and contained ~2 wt% H2O. These values are consistent with previously estimated emplacement pressures and H2O contents of granitic magmas in granitic porphyry-type Cu-Au deposits. Our results demonstrate that MI-homogenization experiments using HDAC at suitably elevated pressures can yield reliable naturally occurring phase transition temperatures in MI during the melt cooling process.
Use of a Telemedicine Risk Assessment Tool to Predict the Risk of Hospitalization of 496 Outpatients With COVID-19: Retrospective Analysis
Authors: O'Keefe James B , Tong Elizabeth J , Taylor Jr Thomas H , O’Keefe Ghazala A Datoo , Tong David C
Published: March 2021

Background

Risk assessment of patients with acute COVID-19 in a telemedicine context is not well described. In settings of large numbers of patients, a risk assessment tool may guide resource allocation not only for patient care but also for maximum health care and public health benefit.

Objective

The goal of this study was to determine whether a COVID-19 telemedicine risk assessment tool accurately predicts hospitalizations.

Methods

We conducted a retrospective study of a COVID-19 telemedicine home monitoring program serving health care workers and the community in Atlanta, Georgia, with enrollment from March 24 to May 26, 2020; the final call range was from March 27 to June 19, 2020. All patients were assessed by medical providers using an institutional COVID-19 risk assessment tool designating patients as Tier 1 (low risk for hospitalization), Tier 2 (intermediate risk for hospitalization), or Tier 3 (high risk for hospitalization). Patients were followed with regular telephone calls to an endpoint of improvement or hospitalization. Using survival analysis by Cox regression with days to hospitalization as the metric, we analyzed the performance of the risk tiers and explored individual patient factors associated with risk of hospitalization.

Results

Providers using the risk assessment rubric assigned 496 outpatients to tiers: Tier 1, 237 out of 496 (47.8%); Tier 2, 185 out of 496 (37.3%); and Tier 3, 74 out of 496 (14.9%). Subsequent hospitalizations numbered 3 out of 237 (1.3%) for Tier 1, 15 out of 185 (8.1%) for Tier 2, and 17 out of 74 (23%) for Tier 3. From a Cox regression model with age of 60 years or older, gender, and reported obesity as covariates, the adjusted hazard ratios for hospitalization using Tier 1 as reference were 3.74 (95% CI 1.06-13.27; P=.04) for Tier 2 and 10.87 (95% CI 3.09-38.27; P<.001) for Tier 3.

Conclusions

A telemedicine risk assessment tool prospectively applied to an outpatient population with COVID-19 identified populations with low, intermediate, and high risk of hospitalization.
Participants’ Engagement and Satisfaction With a Smartphone App Intended to Support Healthy Weight Gain, Diet, and Physical Activity During Pregnancy: Qualitative Study Within the HealthyMoms Trial (Preprint)
Authors: Sandborg Johanna , Henriksson Pontus , Larsen Erica , Lindqvist Anna-Karin , Rutberg Stina , Söderström Emmie , Maddison Ralph , Löf Marie
Published: March 2021

BACKGROUND

Excessive gestational weight gain (GWG) is common and associated with negative health outcomes for both mother and child. Mobile health–delivered lifestyle interventions offer the potential to mitigate excessive GWG. The effectiveness of a smartphone app (HealthyMoms) was recently evaluated in a randomized controlled trial. To explore the users’ experiences of using the app, a qualitative study within the HealthyMoms trial was performed.

OBJECTIVE

This qualitative study explored participants’ engagement and satisfaction with the 6-month usage of the HealthyMoms app.

METHODS

A total of 19 women (mean age: 31.7, SD 4.4 years; mean BMI: 24.6, SD 3.4 kg/m2; university degree attainment: 13/19, 68%; primiparous: 11/19, 58%) who received the HealthyMoms app in a randomized controlled trial completed semistructured exit interviews. The interviews were audiorecorded and fully transcribed, coded, and analyzed using thematic analysis with an inductive approach.

RESULTS

Thematic analysis revealed a main theme and 2 subthemes. The main theme, “One could suit many: a multifunctional tool to strengthen women’s health during pregnancy,” and the 2 subthemes, “Factors within and beyond the app influence app engagement” and “Trust, knowledge, and awareness: aspects that can motivate healthy habits,” illustrated that a trustworthy and appreciated health and pregnancy app that is easy to use can inspire a healthy lifestyle during pregnancy. The first subtheme discussed how factors within the app (eg, regular updates and feedback) were perceived to motivate both healthy habits and app engagement. Additionally, factors beyond the app were described to both motivate (eg, interest, motivation, and curiosity) and limit (eg, pregnancy-related complications, lack of time) app engagement. The second subtheme reflected important aspects, such as high trustworthiness of the app, increased knowledge, and awareness from using the app, which motivated participants to improve or maintain healthy habits during pregnancy.

CONCLUSIONS

The HealthyMoms app was considered a valuable and trustworthy tool to mitigate excessive GWG, with useful features and relevant information to initiate and maintain healthy habits during pregnancy.

CLINICALTRIAL

ClinicalTrials.gov NCT03298555; https://clinicaltrials.gov/ct2/show/NCT03298555

INTERNATIONAL REGISTERED REPORT

RR2-10.2196/13011
Fitness Profile among Malaysian Netball Players
Authors: SOH Kim Geok , HUSAIN Ruby , SOH Kim Lam
Published: March 2021

LANGUAGE NOTE | Document text in English; abstract also in Chinese.The purpose of the study was to determine the fitness performance among Malaysia top netball players, and to compare this study result with others studies or norm. The fitness variables measured were aerobic and anaerobic capacity, leg strength, agility, leg power and sprint ability. Besides that, this study was also carried out to determine whether there was any significant difference in these variables among netball players at different playing positions. A total of 52 Malaysian national netball players were chosen to be the subjects in this study. The 12-minute run, 8 x 35-metre runs, isokinetic leg strength test, SEMO agility test, and the 25-metre sprint test were used to measure the above fitness parameters. Malaysian netball players were reported to have lower aerobic and anaerobic capacity, leg strength, agility, and 25-metre sprint as compared to other countries' netball players. Nevertheless, Malaysian netball players were found to have better leg power and acceleration as compared to other countries' netball players. The center netball players were reported to be superior in V02 max, anaerobic, and agility tests, while the defenders were found to be superior in leg strength, leg power, and sprint tests.本文旨在探討馬來西亞女子投球選手的體能狀況，並與同類研究進行比較及分析。
Decomposition of orthogonal matrix and synthesis of two-qubit and three-qubit orthogonal gates
Authors: Wei Hai-Rui , Di Yao-Min
Published: March 2021

The decomposition of matrices associated to two-qubit and three-qubit orthogonal gates is studied, and based on the decomposition the synthesis of these gates is investigated. The optimal synthesis of general two-qubit orthogonal gate is obtained. For two-qubit unimodular orthogonal gate, it requires at most 2 CNOT gates and 6 one-qubit R_y gates. For the general three-qubit unimodular orthogonal gate, it can be synthesized by 16 CNOT gates and 36 one-qubit R_y and R_z gates in the worst case.
An intuitive proof of the data processing inequality
Authors: Beaudry Normand J. , Renner Renato
Published: March 2021

The data processing inequality (DPI) is a fundamental feature of information theory. Informally it states that you cannot increase the information content of a quantum system by acting on it with a local physical operation. When the smooth min-entropy is used as the relevant information measure, then the DPI follows immediately from the definition of the entropy. The DPI for the von Neumann entropy is then obtained by specializing the DPI for the smooth min-entropy by using the quantum asymptotic equipartition property (QAEP). We provide a short proof of the QAEP and therefore obtain a self-contained proof of the DPI for the von Neumann entropy.
Successfulness of BIM application – reality or wishful thinking?
Authors: Samec Vanja , Lopes Nuno , Strekelj Gregor
Published: March 2021

BIM application in bridge engineering is becoming more and more popular and authorities are worldwide starting to request BIM as a prerequisite for contract awarding. However, some 20 years after the first mention of the term BIM, the postulated processes are to a great extent still piecemeal in this industry.

The heart of the BIM process is hereby a sophisticated digital model of the bridge. The quality of this model,

i.e. the integrity and completeness of its data structure, essentially governs the straight-forward usability for differing purposes, and thus the effectiveness of the BIM process. The advantage of end-to-end data management is often lost, when the dataset is confined to geometric data with ignoring the time as 4thdimension, and when applications like structural analyses require laborious data conversion and supplementation.

A strictly parametric model description is a key-point in this context. I.e. the description contains planning criteria and development rules as part of the model. This data structure allows the direct use for many different applications like visualization, quantity take-off, detailing, draft production, structural analysis and strength assessment. Other key-points are an intelligent and self-explaining user interface and an open structure allowing easy communication over different platforms.

To check the potential savings due to BIM we investigated effectivity issues cropped up in the planning process of a typical concrete bridge. Difficulties and backlashes encountered in the BIM process have been explored. In addition, a pilot project was used for testing an alternative process with a new software tool. By this means we checked, whether the detected problems concerning data conversion and learning phases for using different tools can be avoided by using an approach combining geometric BIM model and analytic model for static analyses.