Search results for: partial vibration

Authors: Chao-Qing Dai

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In modern nonlinear science and textile engineering, nonlinear differential-difference equations are often used to describe some nonlinear phenomena. In this paper, we extend the variable coefficient Jacobian elliptic function method, which was used to find new exact travelling wave solutions of nonlinear partial differential equations, to nonlinear differential-difference equations. As illustration, we derive two series of Jacobian elliptic function solutions of the discrete sine-Gordon equation.

Keywords: discrete sine-Gordon equation, variable coefficient Jacobian elliptic function method, exact solutions, equation

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Authors: Eric S. Parilla, Marc Edward Abadilla

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The study aims to determine the effect of awareness of business students towards cryptocurrencies and the readiness of universities and colleges to accept cryptocurrencies as a medium of exchange, considering the mediation of business students’ attitudes. The research used partial least squares structural equation modeling (PLS-SEM) and deployed a questionnaire attuned to the awareness and attitudes of business students towards cryptocurrencies and readiness and compatibility of use in universities and colleges in Ilocos Norte. The output of the investigation revealed that awareness of business students is not correlated to the readiness of universities and colleges, which means that even though students understand cryptocurrencies, it is not an assurance that universities and colleges are ready to accept them as the medium of exchange. The study proposes that training and seminars for business students and professionals should be conducted to expand understanding and acceptance of cryptocurrencies.

Keywords: cryptocurrencies, awareness, readiness, attitudes

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Authors: Djermani Farouk, Sri Rahayu Hijrah Hati, Fenitra Maminirin, Permata Wulandari

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This study investigates the implications of Artificial Intelligence Marketing (AIM) marketing mix (PRD) Product, (PRC) Price, (PRM), Promotion and (PLC) Place on consumption patterns of halal food (CPHF). A quantitative approach was adopted in this study and responses were obtained from 350 Indonesian consumers. Using Partial Least Squares-Structural Equation Modeling (PLS-SEM), the results show that there is a direct support of marketing mix (PRD, PRC, PLC) to AIM and CPHF, while PRM does not play a significant role in CPHF. In addition, the findings reveal that AIM mediates significantly the relationship between PLC, PRC and PRM and CPHF, while AIM indicates no mediation between PRD and CPHF. Indonesian consumer’s exhibit serious concerns with consumption patterns of halal food. it is recommended that managers focus their attention on marketing strategies to predict consumer behavior in terms of consumption patterns of halal food through the integration of AIM.

Keywords: marketing mix, consumption patterns, artificial intelligence marketing, Halal food

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Authors: Anne C. Okwedadi, Samson Ng’ambi, Ian Jefferson

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Collapsible soils go through radical rearrangement of their particles when triggered by water, stress or/and vibration, causing loss of volume. This loss of volume in soil as seen in foundation failures has caused millions of dollars’ worth of damages to public facilities and infrastructure and so has an adverse effect on the society and people. Despite these consequences and the several studies that are available, more research is still required in the study of soil collapsibility. Discerning the pedogenesis (formation) of soils and investigating the combined effects of the different geological soil properties is key to elucidating and quantifying soils collapsibility. This study presents a novel laboratory testing regime that would be undertaken on soil samples where the effects of soil type, compactive variables (moisture content, density, void ratio, degree of saturation) and loading are analyzed. It is anticipated that results obtained would be useful in mapping the trend of the combined effect thus the basis for evaluating soil collapsibility or collapse potentials encountered in construction with volume loss problems attributed to collapse.

Keywords: collapsible soil, geomorphological process, soil collapsibility properties, soil test

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Authors: Noura Kichou, Manel Tafergguenit, Nabila Ghechtouli, Zakia Hank

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The aim of this work is to synthesize, characterize and evaluate the biological activity of two Ligands : glyoxime and dimethylglyoxime, and their metal Ni(II) chelates. The newly chelates were characterized by elemental analysis, IR, EPR, nuclear magnetic resonances (1H and 13C), and biological activity. The antibacterial and antifungal activities of the ligands and its metal complexes were screened against bacterial species (Staphylococcus aureus, Bacillus subtilis, and Escherichia coli) and fungi (Candida albicans). Ampicillin and amphotericin were used as references for antibacterial and antifungal studies. The activity data show that the metal complexes have a promising biological activity comparable with parent free ligand against bacterial and fungal species. A structural, energetic, and electronic theoretical study was carried out using the DFT method, with the functional B3LYP and the gaussian program 09. A complete optimization of geometries was made, followed by a calculation of the frequencies of the normal modes of vibration. The UV spectrum was also interpreted. The theoretical results were compared with the experimental data.

Keywords: glyoxime, dimetylglyoxime, nickel, antibacterial activity

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Authors: Noura Kichou, Manel Tafergguenit, Nabila Ghechtouli, Zakia Hank

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The aim of this work is to synthesize, characterize and evaluate the biological activity of two Ligands: glyoxime and dimethylglyoxime, and their metal Ni(II) chelates. The newly chelates were characterized by elemental analysis, IR, EPR, nuclear magnetic resonances (1H and 13C), and biological activity. The antibacterial and antifungal activities of the ligands and its metal complexes were screened against bacterial species (Staphylococcus aureus, Bacillus subtilis, and Escherichia coli) and fungi (Candida albicans). Ampicillin and amphotericin were used as references for antibacterial and antifungal studies. The activity data show that the metal complexes have a promising biological activity comparable with parent free ligand against bacterial and fungal species. A structural, energetic, and electronic theoretical study was carried out using the DFT method, with the functional B3LYP and the gaussian program 09. A complete optimization of geometries was made, followed by a calculation of the frequencies of the normal modes of vibration. The UV spectrum was also interpreted. The theoretical results were compared with the experimental data.

Keywords: glyoxime, dimetylglyoxime, nickel, antibacterial activity

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Authors: Sachin Kumar

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Fuzzy fractional diffusion equation is widely useful to depict different physical processes arising in physics, biology, and hydrology. The motive of this article is to deal with the fuzzy fractional diffusion equation. We study a mathematical model of fuzzy space-time fractional diffusion equation in which unknown function, coefficients, and initial-boundary conditions are fuzzy numbers. First, we find out a fuzzy operational matrix of Legendre polynomial of Caputo type fuzzy fractional derivative having a non-singular Mittag-Leffler kernel. The main advantages of this method are that it reduces the fuzzy fractional partial differential equation (FFPDE) to a system of fuzzy algebraic equations from which we can find the solution of the problem. The feasibility of our approach is shown by some numerical examples. Hence, our method is suitable to deal with FFPDE and has good accuracy.

Keywords: fractional PDE, fuzzy valued function, diffusion equation, Legendre polynomial, spectral method

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Authors: A. Şahinoğlu, R. Gürbüz, A. Güllü, M. Karhan

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This study in production machines, it is aimed that machine will automatically perceive cutting data and alter cutting parameters. The two most important parameters have to be checked in machine control unit are progress feed rate and speeds. These parameters are aimed to be controlled by sounds of machine. Optimum sound’s features introduced to computer. During process, real time data is received and converted by Matlab software. Data is converted into numerical values. According to them progress and speeds decreases/increases at a certain rate and thus optimum sound is acquired. Cutting process is made in respect of optimum cutting parameters. During chip remove progress, features of cutting tools, kind of cut material, cutting parameters and used machine; affects on various parameters. Instead of required parameters need to be measured such as temperature, vibration, and tool wear that emerged during cutting process; detailed analysis of the sound emerged during cutting process will provide detection of various data that included in the cutting process by the much more easy and economic way. The relation between cutting parameters and sound is being identified.

Keywords: cutting process, sound processing, intelligent late, sound analysis

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Authors: Emmanuel Omokhuale

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A mathematical model is presented to study free convective boundary layer flow in a semi-infinite vertical cylinder with heat sink effect in a porous medium. The governing dimensional governing partial differential equations (PDEs) with corresponding initial and boundary conditions are approximated and solved numerically employing finite difference method (FDM) the implicit type. Stability and convergence of the scheme are also established. Furthermore, the influence of significant physical parameters on the flow characteristics was analysed and shown graphically. The obtained results are benchmarked with previously published works in order to access the accuracy of the numerical method and found to be in good agreement.

Keywords: free convection flow, vertical cylinder, implicit finite difference method, heat sink and porous medium

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Authors: S. S. P. M. Isa, N. M. Arifin, R. Nazar, N. Bachok, F. M. Ali, I. Pop

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A theoretical study has been presented to describe the boundary layer flow and heat transfer on an exponentially shrinking sheet with a variable wall temperature and suction, in the presence of magnetic field. The governing nonlinear partial differential equations are converted into ordinary differential equations by similarity transformation, which are then solved numerically using the shooting method. Results for the skin friction coefficient, local Nusselt number, velocity profiles as well as temperature profiles are presented through graphs and tables for several sets of values of the parameters. The effects of the governing parameters on the flow and heat transfer characteristics are thoroughly examined.

Keywords: exponentially shrinking sheet, magnetic field, mixed convection, suction

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Authors: Shweta Dhindhwal

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Dopamine is an essential neurotransmitter in the central nervous system of all vertebrates and plays an important role in many processes such as motor function, learning and behavior, and sensory activity. One of the important functions of dopamine is release of pituitary hormones. It is synthesized from the amino acid tyrosine. Two types of dopamine receptors, D1-like and D2-like, have been reported in fish. The dopamine containing neurons are located in the olfactory bulbs, the ventral regions of the pre-optic area and tuberal hypothalamus. Distribution of the dopaminergic system has not been studied in the murrel, Channa punctatus. The present study deals with identification of D2 receptors in the brain of murrel. A phylogenetic tree has been constructed using partial sequence of D2 receptor. Distribution of putative dopaminergic neurons in the brain has been investigated. Also, formalin induced hypertrophy of neurosecretory cells in murrel has been studied.

Keywords: dopamine, fish, pre-optic area, murrel

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Authors: A.Zitouni, S.Bentata, B.Bouadjemi, T.Lantri, W. Benstaali, Z.Aziz, S.Cherid, A. Sefir

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Using the first-principles method, we investigate the structural, electronic, and magnetic properties of the diluted magnetic semiconductors CdCoTe and CdMnTe in the zinc blende phase with 12.5% of Cr. The calculations are performed by a developed full potential augmented plane wave (FP-L/APW) method within the spin density functional theory (DFT). As exchange–correlation potential, we used the new generalized gradient approximation GGA. Structural properties are determined from the total energy calculations and we found that these compounds are stable in the ferromagnetic phase. We discuss the electronic structures, total and partial densities of states and local moments. Finally, CdCoTe and CdMnTe in the zinc-blend phase show the half-metallic ferromagnetic nature and are expected to be potential materials for spintronic devices.

Keywords: DFT, GGA, band structures, half-metallic, spintronics

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Authors: Edén Bojórquez, Victor Baca, Alfredo Reyes-Salazar, Jorge González

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In this paper, simplified equations to predict maximum inter-story drift demands of steel framed buildings are proposed in terms of two ground motion intensity measures based on the acceleration spectral shape. For this aim, the maximum inter-story drifts of steel frames with 4, 6, 8 and 10 stories subjected to narrow-band ground motion records are estimated and compared with the spectral acceleration at first mode of vibration Sa(T1) which is commonly used in earthquake engineering and seismology, and with a new parameter related with the structural response known as INp. It is observed that INp is the parameter best related with the structural response of steel frames under narrow-band motions. Finally, equations to compute maximum inter-story drift demands of steel frames as a function of spectral acceleration and INp are proposed.

Keywords: intensity measures, spectral shape, steel frames, peak demands

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Authors: Tarul Garg, P. N. Agrawal

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We propose to define the q-analogue of the α-Bernstein Kantorovich operators and then introduce the q-bivariate generalization of these operators to study the approximation of functions of two variables. We obtain the rate of convergence of these bivariate operators by means of the total modulus of continuity, partial modulus of continuity and the Peetre’s K-functional for continuous functions. Further, in order to study the approximation of functions of two variables in a space bigger than the space of continuous functions, i.e. Bögel space; the GBS (Generalized Boolean Sum) of the q-bivariate operators is considered and degree of approximation is discussed for the Bögel continuous and Bögel differentiable functions with the aid of the Lipschitz class and the mixed modulus of smoothness.

Keywords: Bögel continuous, Bögel differentiable, generalized Boolean sum, K-functional, mixed modulus of smoothness

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Authors: Khalil Khanafer

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This study emphasizes on analyzing the effect of flow conditions and the geometric variation of the microcantilever’s bluff body on the microcantilever detection capabilities within a fluidic device using a finite element fluid-structure interaction model. Such parameters include inlet velocity, flow direction, and height of the microcantilever’s supporting system within the fluidic cell. The transport equations are solved using a finite element formulation based on the Galerkin method of weighted residuals. For a flexible microcantilever, a fully coupled fluid-structure interaction (FSI) analysis is utilized and the fluid domain is described by an Arbitrary-Lagrangian–Eulerian (ALE) formulation that is fully coupled to the structure domain. The results of this study showed a profound effect on the magnitude and direction of the inlet velocity and the height of the bluff body on the deflection of the microcantilever. The vibration characteristics were also investigated in this study. This work paves the road for researchers to design efficient microcantilevers that display least errors in the measurements.

Keywords: fluidic cell, FSI, microcantilever, flow direction

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Authors: Clairecynth Yu, Geminne Manzano

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The mariculture potential of the Philippine blue sponge, Xestospongia sp. was assessed through the pilot sponge culture in the open-sea at two different biogeographic regions in the Philippines. Thirty explants were randomly allocated for the Puerto Galera, Oriental Mindoro culture setup and the other nine were transported to Lucero, Bolinao, Pangasinan. Two different sponge culture methods of the sponge explants- the lantern and the wall method, were employed to assess the production of the Renieramycin M. Both methods have shown to be effective in growing the sponge explants and that the Thin Layer Chromatography (TLC) results have shown that Renieramycin M is present on the sponges. The effect of partial harvesting in the growth and survival rates of the blue sponge in the Puerto Galera setup was also determined. Results showed that a higher growth rate was observed on the partially harvested explants on both culture methods as compared to the unharvested explants.

Keywords: chemical ecology, porifera, sponge, Xestospongia sp.

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Authors: Jayden R. Hunter, Alexander J. MacQuarrie, Samantha C. Sheridan, Richard High, Carolyn Waite

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Workplace exercise programs have been recommended to improve the musculoskeletal fitness of paramedics with the aim of reducing injury rates, and while they have shown efficacy in other occupations, they have not been delivered and evaluated in Australian paramedics to our best knowledge. This study investigated the effectiveness of a 6-month workplace exercise program (MedicFit; MF) to improve paramedic fitness with or without health coach (HC) support. A group of regional Australian paramedics (n=76; 43 male; mean ± SD 36.5 ± 9.1 years; BMI 28.0 ± 5.4 kg/m²) were randomised at the station level to either exercise with remote health coach support (MFHC; n=30), exercise without health coach support (MF; n=23), or no-exercise control (CON; n=23) groups. MFHC and MF participants received a 6-month, low-moderate intensity resistance and flexibility exercise program to be performed ƒ on station without direct supervision. Available exercise equipment included dumbbells, resistance bands, Swiss balls, medicine balls, kettlebells, BOSU balls, yoga mats, and foam rollers. MFHC and MF participants were also provided with a comprehensive exercise manual including sample exercise sessions aimed at improving musculoskeletal strength and flexibility which included exercise prescription (i.e. sets, reps, duration, load). Changes to upper-body (push-ups), lower-body (wall squat) and core (plank hold) strength and flexibility (back scratch and sit-reach tests) after the 6-month intervention were analysed using repeated measures ANOVA to compare changes between groups and over time. Upper-body (+20.6%; p < 0.01; partial eta squared = 0.34 [large effect]) and lower-body (+40.8%; p < 0.05; partial eta squared = 0.08 (moderate effect)) strength increased significantly with no interaction or group effects. Changes to core strength (+1.4%; p=0.17) and both upper-body (+19.5%; p=0.56) and lower-body (+3.3%; p=0.15) flexibility were non-significant with no interaction or group effects observed. While upper- and lower-body strength improved over the course of the intervention, providing a 6-month workplace exercise program with or without health coach support did not confer any greater strength or flexibility benefits than exercise testing alone (CON). Although exercise adherence was not measured, it is possible that participants require additional methods of support such as face-to-face exercise instruction and guidance and individually-tailored exercise programs to achieve adequate participation and improvements in musculoskeletal fitness. This presents challenges for more remote paramedic stations without regular face-to-face access to suitably qualified exercise professionals, and future research should investigate the effectiveness of other forms of exercise delivery and guidance for these paramedic officers such as remotely-facilitated digital exercise prescription and monitoring.

Keywords: workplace exercise, paramedic health, strength training, flexibility training

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Authors: Mohamed A. Alsharif, Peter A. Wallace, Donald M. Hepburn, Chengke Zhou

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Worldwide, most PILC MV underground cables in use are approaching the end of their design life; hence, failures are likely to increase. This paper studies the electric field and potential distributions within the PILC insulted cable containing common void-defect. The finite element model of the performance of the belted PILC MV underground cable is presented. The variation of the electric field stress within the cable using the Finite Element Method (FEM) is concentrated. The effects of the void-defect within the insulation are given. Outcomes will lead to deeper understanding of the modeling of Paper Insulated Lead Covered (PILC) and electric field response of belted PILC insulted cable containing void defect.

Keywords: MV PILC cables, finite element model/COMSOL multiphysics, electric field stress, partial discharge degradation

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Authors: M. Derayatifar, M. Packirisamy, R.B. Bhat

Abstract:

Role of piezoelectric energy harvesters has gained interest in supplying power for micro devices such as health monitoring sensors. In this study, in order to enhance the piezoelectric energy harvesting in capturing energy from broader range of excitation and to improve the mechanical and electrical responses, bimorph piezoelectric energy harvester beam with magnetic mass attached at the end is presented. In view of overcoming the brittleness of piezo-ceramics, functionally graded piezoelectric layers comprising of both piezo-ceramic and piezo-polymer is employed. The nonlinear equations of motions are derived using energy method and then solved analytically using perturbation scheme. The frequency responses of the forced vibration case are obtained for the near resonance case. The nonlinear dynamic responses of the MEMS scaled functionally graded piezoelectric energy harvester in this paper may be utilized in different design scenarios to increase the efficiency of the harvester.

Keywords: energy harvesting, functionally graded piezoelectric material, magnetic force, MEMS (micro-electro-mechanical systems) piezoelectric, perturbation method

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Authors: Touka Nassim, Tabli Dalila

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In this study, CuO thin films synthesized via simple sol-gel method, have been deposited on glass substrates by the spin coating technique and annealed at various temperatures. Samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier-transform infrared (FT-IR) and Raman spectroscopy, and UV-visible spectroscopy. The structural characterization by XRD reveals that the as prepared films were tenorite phase and have a high level of purity and crystallinity. The crystallite size of the CuO films was affected by the annealing temperature and was estimated in the range 20-31.5 nm. SEM images show a homogeneous distribution of spherical nanoparticles over the surface of the annealed films at 350 and 450 °C. Vibrational Spectroscopy revealed vibration modes specific to CuO with monolithic structure on the Raman spectra at 289 cm−1 and on FT-IR spectra around 430-580 cm−1. Electronic investigation performed by UV–Visible spectroscopy showed that the films have high absorbance in the visible region and their optical band gap increases from 2.40 to 2.66 eV (blue shift) with increasing annealing temperature from 350 to 550 °C.

Keywords: Sol-gel, Spin coating method, Copper oxide, Thin films

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Authors: Pandiyarajan Thangaraj, Mangalaraja Ramalinga Viswanathan, Karthikeyan Balasubramanian, Héctor D. Mansilla, José Ruiz, David Contreras

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We report a systematic study of structural and optical properties of Pr-doped ZnO nanostructures and PVA:Zn98Pr2O polymer matrix nanocomposites free standing films are performed. These particles are synthesized through simple wet chemical route and solution casting technique at room temperature, respectively. Structural studies carried out by X-ray diffraction method, confirms that the prepared pure ZnO and Pr-doped ZnO nanostructures are in hexagonal wurtzite structure and the microstrain is increased upon doping. TEM analysis reveals that the prepared materials are in the sheet-like nature. Absorption spectra show free excitonic absorption band at 370 nm and red shift for the Pr-doped ZnO nanostructures. The PVA:Zn98Pr2O composite film exhibits both free excitonic and PVA absorption bands at 282 nm. Fourier transform infrared spectral studies confirm the presence of A1 (TO) and E1 (TO) modes of Zn-O bond vibration and the formation of polymer composite materials.

Keywords: Pr doped ZnO, polymer nanocomposites, optical properties, free standing film

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Authors: Keita Nishio, Takashi Kaburagi, Yosuke Kurihara

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Recent advances in medical technology have served to enhance average life expectancy. However, the total time for which the patients are prescribed complete bedrest has also increased. With patients being required to maintain a constant lying posture- also called bedsore- development of a system to detect patient roll-over becomes imperative. For this purpose, extant studies have proposed the use of cameras, and favorable results have been reported. Continuous on-camera monitoring, however, tends to violate patient privacy. We have proposed unconstrained bio-signal measurement system that could detect body-motion during sleep and does not violate patient’s privacy. Therefore, in this study, we propose a roll-over detection method by the date obtained from the bi-signal measurement system. Signals recorded by the sensor were assumed to comprise respiration, pulse, body motion, and noise components. Compared the body-motion and respiration, pulse component, the body-motion, during roll-over, generate large vibration. Thus, analysis of the body-motion component facilitates detection of the roll-over tendency. The large vibration associated with the roll-over motion has a great effect on the Root Mean Square (RMS) value of time series of the body motion component calculated during short 10 s segments. After calculation, the RMS value during each segment was compared to a threshold value set in advance. If RMS value in any segment exceeded the threshold, corresponding data were considered to indicate occurrence of a roll-over. In order to validate the proposed method, we conducted experiment. A bi-directional microphone was adopted as a high-sensitivity pressure sensor and was placed between the mattress and bedframe. Recorded signals passed through an analog Band-pass Filter (BPF) operating over the 0.16-16 Hz bandwidth. BPF allowed the respiration, pulse, and body-motion to pass whilst removing the noise component. Output from BPF was A/D converted with the sampling frequency 100Hz, and the measurement time was 480 seconds. The number of subjects and data corresponded to 5 and 10, respectively. Subjects laid on a mattress in the supine position. During data measurement, subjects—upon the investigator's instruction—were asked to roll over into four different positions—supine to left lateral, left lateral to prone, prone to right lateral, and right lateral to supine. Recorded data was divided into 48 segments with 10 s intervals, and the corresponding RMS value for each segment was calculated. The system was evaluated by the accuracy between the investigator’s instruction and the detected segment. As the result, an accuracy of 100% was achieved. While reviewing the time series of recorded data, segments indicating roll-over tendencies were observed to demonstrate a large amplitude. However, clear differences between decubitus and the roll-over motion could not be confirmed. Extant researches possessed a disadvantage in terms of patient privacy. The proposed study, however, demonstrates more precise detection of patient roll-over tendencies without violating their privacy. As a future prospect, decubitus estimation before and after roll-over could be attempted. Since in this paper, we could not confirm the clear differences between decubitus and the roll-over motion, future studies could be based on utilization of the respiration and pulse components.

Keywords: bedsore, high-sensitivity pressure sensor, roll-over, unconstrained bio-signal measurement

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Authors: M. Najafi

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In the present paper, a large turbo-generator shaft train including a heavy-duty gas turbine engine, a coupling, and a generator is established. The method of analysis is based on finite element simplified model for lateral and torsional vibration calculation. The basic elements of rotor are the shafts and the disks which are represented as circular cross section flexible beams and rigid body elements, respectively. For more accurate results, the gyroscopic effect and bearing dynamics coefficients and function of rotation are taken into account, and for the influence of shear effect, rotor has been modeled in the form of Timoshenko beam. Lateral critical speeds, critical speed map, damped mode shapes, Campbell diagram, zones of instability, amplitudes, phase angles response due to synchronous forces of excitation and amplification factor are calculated. Also, in the present paper, the effect of imbalanced rotor and effects of changing in internal force and temperature are studied.

Keywords: rotor dynamic analysis, finite element method, shaft train, Campbell diagram

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Authors: M. S. Ahmed, F. A. Mohammad

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The aim of this paper is to perform experimental modal analysis (EMA) of reinforced concrete (RC) square slabs. EMA is the process of determining the modal parameters (Natural Frequencies, damping factors, modal vectors) of a structure from a set of frequency response functions FRFs (curve fitting). Although experimental modal analysis (or modal testing) has grown steadily in popularity since the advent of the digital FFT spectrum analyzer in the early 1970’s, studying all members and materials using such method have not yet been well documented. Therefore, in this work, experimental tests were conducted on RC square specimens (0.6m x 0.6m with 40 mm). Experimental analysis is based on freely supported boundary condition. Moreover, impact testing as a fast and economical means of finding the modes of vibration of a structure was used during the experiments. In addition, Pico Scope 6 device and MATLAB software were used to acquire data, analyze and plot Frequency Response Function (FRF). The experimental natural frequencies which were extracted from measurements exhibit good agreement with analytical predictions. It is showed that EMA method can be usefully employed to perform the dynamic behavior of RC slabs.

Keywords: natural frequencies, mode shapes, modal analysis, RC slabs

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Authors: Marcin Maslowski, Marian Zaborski

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The aim of the study was to receive magnetorheological elastomer composites (MRE) with the best mechanical characteristics. MRE based on different magnetoactive fillers in ethylene-octene rubber are reported and studied. To improve mechanical properties of polymer mixtures, also carbon black (N550) was added during the composites preparation process. Micro and nan-sized magnetites (Fe3O4), as well as gamma iron oxide (gamma-Fe2O3) and carbonyl iron powder (CIP) are added together with carbon black (N550) were found to be an active fillers systems improving both static and dynamic mechanical properties of elastomers. They also changed magnetic properties of composites. Dynamic-mechanical analysis (DMA) indicates the presence of strongly developed secondary structure in vulcanizates. Reinforcing character of applied different fillers systems results in an increased stress at 100% elongation, tensile strength and cross-linking density of the vulcanizates. Studies investigated by vibration sample magnetometer (VSM) proved that all composites exhibit good magnetic properties.

Keywords: carbon black, mechanical properties, magnetorheological composites, magnetic fillers

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Authors: Fatima S. Rodriguez, Victorino T. Taylan, Manolito C. Bulaong, Helen F. Gavino, Vitaliana U. Malamug

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In sundrying, the quality of the grains are greatly reduced when paddy grains were caught by the rain unsacked and unstored resulting to reduced profit. The objectives of this study were to design and fabricate a quick covering machine for grain drying pavement to test and evaluate the operating characteristics of the machine according to its deployment speed, recovery speed, deployment time, recovery time, power consumption, aesthetics of laminated sack, conducting partial budget, and cost curve analysis. The machine was able to cover the grains in a 12.8 m x 22.5 m grain drying pavement at an average time of 17.13 s. It consumed 0 .53 W-hr for the deployment and recovery of the cover. The machine entailed an investment cost of $1,344.40 and an annual cost charge of $647.32. Moreover, the savings per year using the quick covering machine was $101.83.

Keywords: quick, covering machine, grain, drying pavement

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Authors: Jiří Klečka, Dagmar Čámská

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This paper is focused on the investigation of productivity (total productivity and partial productivity). The value productivity is an indicator of level and changes in technical economic efficiency of production factors. It represents an important factor in achieving corporate objectives. This text works with the contemporary concept of value productivity that means that indicators of the productivity express the effect of economic efficiency not only of inputs consumption, but also of inputs binding efficiency. This approach is based on principles of the economic profit, respectively the economic value added (EVA). The research is done on the sample of Czech enterprises operating in the automotive industry in the regions of Liberec and the Central Bohemia. The data sample covers the time period 2006-2011 which allows the comparison of development before crisis and during crisis period. It enables to discover the companies' reaction during crises and the regional comparison allows to showing if there are significant differences between regions.

Keywords: automotive industry, Czech Republic, economic efficiency, regional comparison, value productivity

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Authors: Emine Öğüt, Mehtap Öztürk, Adem Öğüt

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Affective commitment is defined as a strong belief in and acceptance of the organization’s goals and values. Organizational justice is an antecedent of the organizational commitment and it has the potential to create powerful benefits for organizations and employees alike. When perceived unfairness among employees increases, affective commitment decreases and absenteeism increases accordingly. In this research, relationships between organizational justice perception, affective commitment and absenteeism is analysed. In this regard, a field study has been conducted over the physicians working in the hospitals of the Health Ministry and University Hospitals in the province of Konya. The partial least squares (PLS) method is used to analyse the survey data. The findings of the research shows that there is a positive statistically significant relationship between organizational justice perception and affective commitment while there is a negative statistically significant relationship between organizational justice and absenteeism.

Keywords: organizational justice, affective commitment, absenteeism, healthcare management

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Authors: Jui-Pui Hung, Yong-Run Chen, Wei-Cheng Shih, Chun-Wei Lin

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This study was aimed to assess the variations of the modal characteristics of the feeding stage with different linear guide modulus. The dynamic characteristics of the feeding stage were characterized in terms of the modal stiffness, modal frequency and modal damping, which are assessed from the vibration tests. According to the experimental measurements, the actual preload of the linear guide modulus was found to deviate from the rated values as setting in factory. This may be due to the assemblage errors of guide modules. For the stage with linear guides, the dynamic stiffness was affected to change by the preload set on the rolling balls. The variation of the dynamic stiffness at first and second modes is 20.8 and 10.5%, respectively when the linear guide preload is adjusted from medium and high amount. But the modal damping ratio is reduced by 8.97 and 9.65%, respectively. For high-frequency mode, the modal stiffness increases by 171.2% and the damping ratio reduced by 34.4%. Current results demonstrate the importance in the determining the preloaded amount of linear guide modulus in practical application.

Keywords: contact stiffness, feeding stage, linear guides, modal characteristics, pre-load

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Authors: Sachin Nagargoje

Abstract:

Complete labeled data is often difficult to obtain in a practical scenario. Even if one manages to obtain the data, the quality of the data is always in question. In shopping vertical, offers are the input data, which is given by advertiser with or without a good quality of information. In this paper, an author investigated the possibility of using a very simple Semi-supervised learning approach to increase the recall of unhealthy offers (has badly written Offer Title or partial product details) in shopping vertical domain. The author found that the semisupervised learning method had improved the recall in the Smart Phone category by 30% on A=B testing on 10% traffic and increased the YoY (Year over Year) number of impressions per month by 33% at production. This also made a significant increase in Revenue, but that cannot be publicly disclosed.

Keywords: semi-supervised learning, clustering, recall, coverage

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