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BACKGROUND Noise exposures are associated with a host of adverse health effects, yet these exposures remain inadequately characterized in many industrial operations, including paper mills. We assessed noise at four paper mills using three measures: (i) personal noise dosimetry, (ii) area noise measurements, and (iii) questionnaire items addressing several different aspects of perceived noise exposure. METHODS We assessed exposures to noise characterized using the three measures and compared the relationships between them. We also estimated the validity of each of the three measures using a novel application of the Method of Triads, which does not appear to have been used previously in the occupational health literature. RESULTS We collected 209 valid dosimetry measurements and collected perceived noise exposure survey items from 170 workers, along with 100 area measurements. We identified exposures in excess of 85 dBA at all mills. The dosimetry and area noise measurements assigned to individual subjects generally showed good agreement, but for some operations within mill, large differences between the two measures were observed, and a substantial fraction of paired measures differed by >5 dB. Perceived noise exposures varied greatly between the mills, particularly for an item related to difficulty speaking in noise. One perceived noise exposure item related to difficulty hearing due to noise showed strong and significant correlations with both dosimetry and area measurements. The Method of Triads analysis showed that dosimetry measures had the highest estimated validity coefficient (0.70), and that the best performing perceived exposure measure had validity that exceeded that of area measurements (0.48 versus 0.40, respectively). CONCLUSIONS Workers in Swedish pulp mills have the potential for exposures to high levels of noise. Our results suggest that, while dosimetry remains the preferred approach to exposure assessment, perceived noise exposures can be used to evaluate potential exposures to noise in epidemiological studies.

Noise optimization for FET low noise amplifiers (LNAs) are demonstrated through insights gained from analytical formulations derived using noise transformation matrix. The invited paper reviews the status of analytical noise optimization of FET LNAs including single-/dual-band FET LNAs with the lossless/lossy input match networks and broadband FET LNAs with the lossless input networks.

Noise is one of the problems that often occur in urban areas due to the traffic condition. Noise in a building design depends on the choice of materials as sound absorbers. The type of sound dampening material that already exists is a porous material, a resonator, and a panel. The material often used as an absorber is porous materials, because it is relatively cheaper and lighter, especially to reduce the noise in the narrow spaces such as housing and offices. Various substitutes are made from cheap materials, such as the use of recycled materials of egg tray paper with the size of 40 x 40 centimeters. This is a quantitative research that will measure the place of egg tray paper in reducing noise, using a Sound Level Meter. The use of the egg tray paper is able to show an adequate acoustic quality as noise absorbers, with the average value of NR 22-26 dB.

This paper presents an analysis of the sensitivity function and complementary sensitivity function for stock consistency process models using Particle Swarm Optimization-(PSO) based conventional Proportional-Integral (PI) and Proportional-Integral-Derivative (PID) controllers. The analysis of these functions is required to test the effect of disturbances, noise, and variation in process dynamics on the process output, i.e., to check the robustness of the controllers. The PI controller has been designed using a fuzzy login-based PSO algorithm. The objective is to determine the optimal controller tuning parameters using a proposed algorithm such that the effect of process variations and disturbances is minimum on the process output. The peak values of sensitivity and complementary sensitivity functions have been obtained through MATLAB along with the closed-loop bandwidth of the proposed control system. Also, the time taken by proposed controllers to suppress the effect of disturbance and noise has also been evaluated. The comparison has been done between PSO–PI and PID controllers on the basis of the above-mentioned criterion. From the comparative analysis, it has been observed that the PSO–PI controller exhibits better robustness as compared to the PSO–PID controller.

There is growing interest in the concepts of listening effort and fatigue associated with hearing loss. However, the theoretical underpinnings and clinical meaning of these concepts are unclear. This lack of clarity reflects both the relative immaturity of the field and the fact that research studies investigating listening effort and fatigue have used a variety of methodologies including self-report, behavioural, and physiological measures.This discussion paper provides working definitions for listening effort and listening-related fatigue. Using these definitions as a framework, methodologies to assess these constructs are reviewed.Although each technique attempts to characterize the same construct (i.e. the clinical presentation of listening effort and fatigue), different assumptions are often made about the nature of these phenomena and their behavioural and physiological manifestations.We suggest that researchers consider these assumptions when interpreting their data and, where possible, make predictions based on current theoretical knowledge to add to our understanding of the underlying mechanisms of listening effort and listening-related fatigue.Following recent interest in the cognitive involvement in hearing, the British Society of Audiology (BSA) established a Special Interest Group on Cognition in Hearing in May 2013. In an exploratory group meeting, the ambiguity surrounding listening effort and fatigue was discussed. To address this problem, the group decided to develop a 'white paper' on listening effort and fatigue. This is a discussion document followed by an international set of commentaries from leading researchers in the field. An approach was made to the editor of the International Journal of Audiology who agreed to this suggestion. This paper, and the associated commentaries that follow, are the result.

This paper gives a review on the various modulation techniques that have been used to eliminate lower-order harmonics in multilevel inverters. The output voltage with high quality can be achieved using multilevel inverters. The selection is based on switching losses, power losses, noise, etc. Many authors proposed different modulation techniques such as sine triangular, selective harmonic selection (SHE), model predictive control techniques, space-vector-based modulation techniques. This paper presents a detailed review of existing harmonic elimination methods as well as concludes with the best method.

Superposition and entanglement, the quintessential characteristics of quantum physics, have been shown to provide communication, computation, and sensing capabilities that go beyond what classical physics will permit. It is natural, therefore, to explore their application to radar, despite the fact that decoherence—caused by the loss and noise encountered in radar sensing—destroys these fragile quantum properties. This paper tells the story of “quantum illumination”, an entanglement-based approach to quantum radar, from its inception to its current understanding. Remarkably, despite loss and noise that destroys its initial entanglement, quantum illumination does offer a target-detection performance improvement over a classical radar of the same transmitted energy. A realistic assessment of that improvement’s utility, however, shows that its value is severely limited. Nevertheless, the fact that entanglement can be of value on an entanglement-breaking channel—the meta-lesson of the quantum illumination story—should spur continued research on quantum radar.

Application of image frequency filtering to elimination of the noise in scanned photographs caused by the embossing of the photographic paper is considered.

As the number of cores grow in HPC systems, so does the effect of system noise on applications running on these systems. With the knowledge that future large-scale parallel computer systems, including exascale systems, will operate under an overall power bound, we claim to have found a solution that can counter the effects of noise. We present two methods that estimate the effects of noise on an application and then optimally redistributes power among nodes, such that the effects of noise are "hidden".

The difference between conventional replicator dynamics and pairwise (PW) nonlinear Fermi dynamics can be discerned by studying the evolutionary dynamics of the interactions between the symmetric cyclic structure in the rock–paper–scissors game and inter- and intraspecific competitions. Often, conventional replicator models presume that the payoff difference among species is a linear function (a linear benefit). This study introduces a PW contrast under the properties of the well-known Fermi rule, where species play against one another in pairs. To model a PW nonlinear evolutionary environment (a nonlinear benefit) within this framework, both analytical and numerical approaches are applied. It is determined that the dynamics of the linear and nonlinear benefits can present the same stability conditions at equilibrium. Moreover, it is also demonstrated that, even in an identical equilibrium condition for both dynamics, the numerical result run by a deterministic approach presents a faster stability state for nonlinear benefit dynamics. This study also suggests that introducing mutation as demographic noise can effectively disrupt the phase regions and show the different relationships between linear and nonlinear dynamics. The symmetric bidirectional mutation among all the species reduced to the stable limit cycle by an arbitrary small mutation rate is also explored. Due to the environmental noise, however, linear and nonlinear exhibit the same steady state. Nevertheless, non-linearity illustrates more stable and faster stability situations. Our result suggests that environmental and demographic noise on the evolutionary dynamic framework can serve as a mechanism for supporting PW nonlinear dynamics in multi-species games.

Higher noise level in heavy industries is harmful for workers. It causes ill effects like hearing loss, tired, weakness, higher blood pressure on health of industrial workers. Therefore, to improve the environment of the workplace and reduce unwanted noise in industries it is very important to find out effective and harmless noise control methods. The research work was conducted to investigate use of natural materials for industrial noise reduction to give effective solution for existing industrial noise problem .specimens having size of 75 mm (dia.) and 12.5mm, 25mm (thick.) were cast. Noise reduction coefficients of prepared specimens were calculated by using an experimental set-up. Experimental set-up consisted Noise level meter, function generator, speaker. Noise reduction capacity of materials was calculated by using Noise reduction coefficient (NRC). Effectiveness of natural materials for industrial noise reduction is discussed in this paper.

This paper shows how a standard proportional-integral-plus controller, based on a non-minimal state space (NMSS) design, can be extended to reduce the effects of measurement noise and so yield smoother control inputs for automated drug delivery control applications. Use of a NMSS model for state variable feedback control design, in which all the states are based on the directly measured input and output variables, removes the need for state estimation. Nonetheless, a stochastic NMSS form, with a Kalman filter, can optionally be introduced to reduce the effect of measurement noise and so yield smoother control inputs. In this case, the Kalman filter attenuates measurement noise but does not address state disturbances. In this article, we propose a modification to the stochastic NMSS control system to enable the elimination of such state disturbances. This involves further extending the non–minimal state vector to include additional terms based on the innovations. We compare the deterministic, stochastic and extended stochastic NMSS controllers via a simulation of the control of anaesthesia using propofol.

Multi-sensor object detection and tracking on a highway scene with radar measurements is presented. The estimation algorithm is the random finite set based Bernoulli filter, working in the Bayesian framework. The recursion for calculating the Bayes estimation is implemented as a particle filter. A method is presented for calculating the likelihoods, suitable for particle filtering performed with moving sensors, assuming additive Gaussian measurement noise. In our approach, for calculating the posterior estimate of the object state, the measurement likelihoods are computed in the state space, instead of the measurement space, by mapping each measurement to the global coordinate system. The map consists of a nonlinear and an affine part. While the affine transformation trivially preserves the Gaussian nature, the nonlinear is well-proven to be approximated as affine too. This approach allows the particles to be drawn directly from the state space, hence the evaluation of the measurement model is not needed, which saves computational power.

Emerging non-volatile memory (NVM) technologies are being aggressively explored to replace and/or assist conventional CMOS technology. Although NVMs can cut down leakage power, achieve low footprint and allow compute capability along with storage, they suffer from new sources of variability. We review the noise sources associated with NVMs and describe resilience enhancement techniques for both memory and computing. We also present security applications where noise and variability is desirable.

Purpose: In developing new products, reducing performance variation is important for competitiveness factors such as quality, cost, and delivery. This paper aims at evaluating three performance variations; measurement, performance evaluation, and manufacturing variations, and then improving product and process design, focused on paper helicopter making case study. Methods: For measurement system analysis, gage R&R (repeatability and reproducibility), linearity, stability are evaluated. Since gage R&R are not satisfactory, the measurement system is improved by adopting voice memos application of iPhone and providing standard measurement procedure. To evaluate performance varia- tion, product deterioration and environment factor (wind speed) is considered. Since the existing design is sensitive to these noise factors, a new product design is developed, which is proven to be robust to the noise factors. Finally, manufacturing variations are evaluated with five factors which can cause variation in flight time. To reduce the impact of three significant factors, three improvement methods are applied. Results: Three performance variations are evaluated and robust paper helicopter design is presented. Conclusion: To reduce measurement and process variations, improved measurement method and paper heli- copter making procedure are proposed. A new product design is also presented which is robust to deterioration

In controlling uncertain processes, it is decisive to utilize information provided by measurements in order to estimate parameters and states. Nonlinear Model Predictive Control (NMPC) is a popular method to implement feedback control and deal with uncertainties. Conventional NMPC or nominal control, however, sometimes does not provide enough information for system estimation, leading to unsatisfactory performance. Dual control attempts to strike a balance between the two goals of enhancing system estimation and optimizing the nominal objective function. In this paper, we analyze the performance of these strategies through the interplay between the performance control task and the information gain task in connection with Optimal Experimental Design. Examples illustrate the conflict and agreement between the two tasks and explain why in some cases nominal control performs well. It is also observed that measurement noise provides excitation helping to improve the quality of estimates.

This article presents a review of current aircraft noises. Noise is a fascinating area of research combining statistics, applied mathematics, and engineering. Aircraft noises are an impact of enormous financial, environmental, and technological issue. Aircraft noise remains the key inhibitor of the growth of air transportation and remains an acute environmental problem that requires advanced solutions. To advance our understanding of the sound source mechanisms, it should be noted that predominant noise sources of aircraft engines are from the exhaust (referred to as the jet) and fan (including the stator). The noise generated in these two areas during takeoff and landing has a strong influence on the communities around the airports. One of the most important sources of aircraft noises in modern jet aircraft is the turbulence that occurs in the shear layers around the engine’s exhaust. But this is not just an academic issue also jet noise is highly relevant to the aviation industry and on a wider scale, has been related to economic, social, and subsequently political. To deal with this problem, aircraft manufacturers and public establishments are engaged in research on technical and theoretical approaches for noise reduction concepts that should be applied to new aircraft. This review paper discusses a selection of enabling technologies and their implications on acoustics and noise and gives a perspective on future trends and new directions in aeroacoustics required to address the challenges.

In this paper, a practical multiple input multiple output Dirty paper coding (MIMO-DPC) scheme is designed to cancel the effect of additive interference that is known perfectly to the transmitter. The proposed system uses a trio of encoders — a LDPC code, a vector quantizer implemented as a convolutional decoder and an Orthogonal space time block code (STBC) to achieve temporal coding gain, interference cancelation and spatial diversity, respectively. First, we derive the equivalent noise seen by the receiver using an equivalent lattice based dirty paper code. Then the optimal value of the power inflation factor, which is one of the key system parameters used to minimize the equivalent noise seen by the receiver is derived. Furthermore, we analytically prove that the equivalent noise seen by the receiver tends to 0 for large number of receive antennas. Performance results in the case of various number of receiver antennas are presented and show that significant reduction in bit error probabilities can be obtained over a system that uses no interference cancelation.

In this work we have studied a stochastic predator-prey model where the prey grows logistically in the absence of predator. All parameters but carrying capacity have been perturbed with telephone noise. The prey’s growth rate and the predator’s death rate have also been perturbed with white noises. Both of these noises have been proved extremely useful to model rapidly fluctuating phenomena Dimentberg (1988). The conditions under which extinction of predator and prey populations occur have been established. We also give sufficient conditions for positive recurrence and the existence of an ergodic stationary distribution of the positive solution, red which in stochastic predator-prey systems means that the predator and prey populations can be persistent, that is to say, the predator and prey populations can be sustain a quantity that is neither too much nor too little. In our analysis, it is found that the environmental noise plays an important role in extinction as well as coexistence of prey and predator populations. It is shown in numerical simulation that larger white noise intensity will lead to the extinction of the population, while telephone noise may delay or reduce the risk of species extinction.

Jai-Hyun Byun ․Yong Tae Kim․Min Ji LeeDepartment of Industrial and Systems Engineering and Engineering Research Institute Gyeongsang National University, Jinju, 660-701Robust design method developed by Genichi Taguchi has been very popular since the 1980s and there have been many academic and applied research works on this topic. However, college students and engineers in companies have had difficulty in understanding the method. This paper presents a procedure to implement the robust design method by an easy-to-execute paper helicopter experiment. A crossed array was adopted, which consists of a resolution IV fractional factorial design with 6 control factors and a factorial design with 3 noise factors. Three performance measures were analyzed; signal-to-noise ratio, mean, and standard deviation of the falling time of the paper helicopter that is to be maximized. Control-noise interaction plots are also given to evaluate the degree of the sensitivity of each level of the control factors to the noise factors. The procedure presented in this paper can be helpful to those who want to have basic knowledge in the robust design method.

This paper presents a novel approach and its application to the modelling of non-linear unknown systems via B-spline neural networks. The system is assumed to be described by a NARMAX model, which is subjected to coloured noise. A new regression formula is constructed and it has been shown that the generalised RLS algorithm can be directly applied to train the weights and produce a desirable estimate on the various modes of the noise. The selection of the knots distribution of B-spline neural networks is also considered. An algorithm has been developed which produces an optimal knot distribution for an input axis using training data. Finally, the method developed is applied to build up a local model for a paper machine wet end, which represents the relationship between added chemicals (rosin and alum) and the sizing of the resulting paper. Desired results are obtained.

A modified paper clock timescale weighted after removing the linearized frequency drift of each cesium clock in TL's 12-cesium-clock ensemble is used to be the mid-term prediction reference before the next coming BIPM Circular T announcement. After removing the frequency drift pattern according to Circular T announcements, the noise type of each cesium clock in ensemble is dominated by white noise when the average time was less than about 100 days. To achieve approximately equal weighting and rational upper limit, an inversely exponential weighting procedure is also used to weight each cesium clock according to the inversely exponential function of their Allan variance; for our 12-cesium-clock ensemble, a 4 years test shows the phase error of the paper clock time scale is less than 10 ns in 45 days prediction.

A simple wind speed measurement device, a paper anemometer, is fabricated based on the theory of standing waves. In providing the working profile of the paper anemometer, an experimental device is established, which consists of an anemometer sensor, a sound sensor, a microphone, paper strips, a paper cup, and sonic acquisition software. It shows that the sound wave detected in the paper cup has a larger amplitude and the noise is depressed, though the frequency of the sound is twice that detected directly from the strip. From the experiments, we find that the frequency of the sonic wave does not change with wind speed; however, its amplitude increases with wind speed. To predict the wind speed, a correlation is established from the sound wave amplitude.

The strapping machine for Paper Bills typically was designed to reduce labor intensity and enhance production automation level. The machines structure and working principle were described. There are three work posts in this equipment, they work continuously. This approach makes it very easy to split up a complex transformation into a series of simple transformations arranged in a loop line. The machine includes currency count/counterfeit distinguishing system, conveying system and strapping system. In the same time, the machine control system that adopts the PLC programmable controller can simplify the control system, and its reliability strengthens further. Practices show that the strapping machine has the advantages of simple structure, high efficiency, low cost and small vibrating noise.

Surface roughness is one of the most important attributes of paper and its measurement is normally used in quality control applications. Currently, measurement of surface roughness is done by using air leakage, optical, or subjective methods. In this article, an acoustical method for the determination of surface roughness of papers is described. The method is applied off-line and uses the friction noise recorded when a small brush slide over the surface of the paper. The analysis is done consider the friction noise ranging from 300 Hz to 10 kHz. Considering that friction noise is associated to surface roughness, a signal analysis algorithm was developed to take advantage of this fact. The algorithm consists of a frequency-domain feature extraction routine and an artificial neural network that represents the variation of the spectral features in a roughness scale. The results show that an affordable and efficient friction noise based system can be used for measuring surface roughness of tissue papers and other soft surfaces as an alternative to other methods.

This field study aimed to evaluate the prevalence of annoyance and disturbance and the subjective perception of the sound environment due to noise, in an old and a new control room at a large paper mill. Working in a control room requires sustained attention and concentration and, in the case of error messages, rapid and correct decisions. In this study, the personnel's responses were collected by questionnaire, and detailed sound measurements were taken in both control rooms. The A-weighted sound pressure level in the new control room was 54.9 dB, a reduction from the 63.5 dB measured in the old room, and the C-weighted sound pressure level was 66.8 dB, a reduction from the 75.2 dB measured in the old room. The new control room was rated as being a less noisy environment; however, the personnel did complain about noise from other computers/equipment, radios, and the new laboratory.

In this article we describe a method for determining the elastic constants for paper from a measured displacement field. Our model is based on the finite element method using quadrilateral elements. A method for finding the first and second order derivatives with respect to the unknown parameters plays a crucial role in the optimization process used to solve the inverse problems in this article. To reduce the influence of the noise of the input data, an efficient continuation method is used for the regularization term in the cost function. Some numerical results for synthetic data and measurement will verify the efficiency of our approach.

We study a spatial evolutionary rock-paper-scissors game with synchronized strategy updating. Players gain their payoff from games with their four neighbors on a square lattice and can update their strategies simultaneously according to the logit rule, which is the noisy version of the best-response dynamics. For the synchronized strategy update two types of global oscillations (with an ordered strategy arrangement and periods of three and six generations) can occur in this system in the zero noise limit. At low noise values, all nine oscillating phases are present in the system by forming a self-organizing spatial pattern due to the comprising invasion and speciation processes along the interfaces separating the different domains.

Dose–response relationships of the sort pioneered by Schultz figure prominently in the current European noise regulation policy. A position paper developed by the Working Group on Dose‐effects (part of the EU Expert Network) reviewed a range of potential health effects, but decided that annoyance and sleep disturbance remain the most prevalent and sensitive effects of transportation noise exposure, and those for which the best data were available. A Position paper providing guidance on the dose–effect relations to be used for the assessment of numbers of people annoyed by noise from transportation sources (rail, road and air) may be found at http://europa.eu.int/comm/environment/noise/home.htm This presentation explains the context in which the Paper was developed, outlines the process by which the dose–response relationships were derived and summarizes the key recommendations. Finally some observations are made as the Position Paper is being applied, and related future developments are discussed. The author acknowledges with deep gratitude the assistance of Dr. Henk Miedema of TNO in preparing this paper.

I give a simple analysis of the game that I previously published in Scientific American which shows the paradoxical behavior whereby two losing games randomly combine to form a winning game. The game, modeled on a random walk, requires only two states and is described by a first-order Markov process.

We consider the problem of identifying multivariable finite dimensional linear time-invariant systems from noisy input/output measurements. Apart from the fact that both the measured input and output are corrupted by additive white noise, the output may also be contaminated by a term which is caused by a white input process noise; furthermore, all these noise processes are allowed to be correlated with each other. We shall develop a solution to this problem in the framework of subspace identification and we shall show that our algorithms give consistent estimates when the system is operating in open- or closed-loop. Two realistic simulation studies are presented to demonstrate the practical applicability of the proposed algorithms. © 1997 Elsevier Science Ltd.

Low-frequency noise caused by intestinal gas, bone, or high-contrast subjects on roentgenographs often makes them difficult to read. The plantodorsal projection of the calcaneus taken by the conventional method has low-frequency noise because of its own high contrast for the long axis. Even if a higher X-ray tube voltage is used to reduce the low-frequency noise, middle- or high-frequency signals such as those of bone trabeculae are also reduced. We investigated a new method that takes into consideration the subject contrast between the part of the posterior calcanean articulation and distal part on the calcaneus projection, the spectrum of bone trabeculae, and the scatter fraction. The technique we introduced has some merit compared with the conventional method in that it reduces image distortion, provides low contrast for the long axis, and sharpens trabeculae images and articulations.

Glitches and errors within digital media technology are hardly ever greeted gladly. Hardware failures, signal losses, and corrupt files have the potential to be personally and professionally catast...

Two-phase flow exists in many industrial components. To avoid costly vibration problems, sound technology in the area of two-phase flow-induced vibration is required. This paper is an overview of the principal mechanisms governing vibration in two-phase flow. Dynamic parameters such as hydrodynamic mass and damping are discussed. Vibration excitation mechanisms in axial flow are outlined. These include fluidelastic instability, phase-change noise, and random excitation. Vibration excitation mechanisms in cross-flow, such as fluidelastic instability, periodic wake shedding, and random excitation, are reviewed.