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Hearing loss at call centres is a major issue all around the world. Exposure to excessive and continuous high levels of noise can result in both temporary and permanent hearing damage. Professor Setsuo Maeda of Kinki University, Japan, has unique experience and expertise in this area, and has carried out research at a small call centre on the Japanese island of Okinawa. Using the latest technology, Dr Maeda has compared the noise exposure risks and speech intelligibility of traditional headsets with the latest bone-conducting devices available.

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Brüel & Kjær’s LDS shakers and vibration test systems are designed and built with a unique blend of global experience, the latest advanced technologies, and a highly motivated workforce that prides itself on making the best vibration test systems in the world.

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石橋製作所は、風力発電用ギヤボックスの製造で多くの企業が直面する課題を抱えています。それは、顧客の投資に対する利益に重大な影響を及ぼす、信頼性と製品寿命の保証です。石橋製作所が使用するPuLseデータ収集システムとトランスデューサは、会社と共に拡張されるであろう総合試験スタンドの一部を担っています。

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The paper describes a commercially available fly-over beamforming system based on methodologies already published, but using an array that was designed for quick and precise deployment on a concrete runway rather than for minimum sidelobe level. Time domain tracking Delay And Sum (DAS) beamforming is the first processing step, followed by Deconvolution in the frequency domain to reduce sidelobes, enhance resolution, and get absolute scaling of the source maps. The system has been used for a series of fly-over measurements on a Business Jet type MU300 from Mitsubishi Heavy Industries. Results from a couple of these measurements are presented: Contribution spectra from selected areas on the aircraft to the sound pressure level at the array are compared against the total sound pressure spectrum measured by the array. One major aim of the paper is to verify that the system performs well although the array was designed with quick deployment as a main criterion. The results are very encouraging. A second aim is to elaborate on the handling of the array shading function in connection with the calculation of the Point Spread Function (PSF) used in deconvolution. Recent publications have used a simple formula to compensate for Doppler effects for the case of flat broadband spectra. A more correct formula is derived in the present paper, covering also a Doppler correction to be made in the shading function, when that function is used in the PSF calculation.

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Ishibashi faces a familiar challenge in manufacturing wind turbine gearboxes – ensuring the reliability and longevity that is critical to their customer’s return on investment. The PULSE data acquisition systems and transducers Ishibashi uses are part of a comprehensive test stand setup that is ready to expand with the company.

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The number of noise source identification (NSI) techniques available to engineers working on noise, vibration and harshness problems has increased considerably in recent years. The choice of the most appropriate technique depends upon the application and the information required. This paper reviews techniques for noise source identification and quantification ranging from simple hand-held sound intensity systems, hand-held array systems to large ground based microphone arrays. The methods include Beamforming, Spherical Beamforming and Acoustic Holography. Guidelines are given to help the engineer choose a suitable technique based on the frequency range of interest, the distance from the measurement array to the test object and the resolution required. Practical application examples ranging from hearing aids to wind turbines are presented to illustrate the various NSI techniques.

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Brüel & Kjær’s permanently mounted accelerometers were developed in close collaboration with AgustaWestland to monitor helicopter gearbox health on the AW139.

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When Brüel & Kjær needed assistance during the beta development phase of the post-processing platform PULSE Reflex, getting Continental’s input was a high priority. For Continental AG’s NVH Engineering department it was an opportunity to ‘try before you buy’, so they set about comparing the results between their existing PULSE LabShop real-time analysis platform and the new post-processing platform PULSE Reflex – which turned out to be even better than they expected.

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ノイズスコープ（PULSE ベースビームフォーミングシステム）は、道路交通騒音の影響を受ける地域の騒音を測定するために、株式 会社高速道路総合研究所（NEXCO 総研）のご要望を満たすように、車載できる可動式の特注アレイを含めて納品されました。その 測定対象は、住居地域、橋梁、インターチェンジ、合流、トンネル、料金所などです。ノイズスコープを使用することによりNEXCO 総研は、交通量の増加に伴う厳しい影響を低減させるために、高速道路とその付帯設備の設計及び建設を最適化させることが可能と なります。

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With component production facilities around the world contributing to the manufacture of exacting measurement equipment, Brüel & Kjær needs detailed and strictly centralised control of production test targets. When a new system was called for to maintain R&D targets in production by tracking and analysing test outcomes around the world, we decided to build our own.

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EEI advises companies on how to fulfil government standards for consumer electronics, helping companies selling into the Thai market and helping Thai businesses exporting to Europe and around the world. They do this through consulting, training and seminars, and performing testing services that include sound power and electromagnetic compatibility.

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For identifying feedback due to leakage or vibration in hearing aids, a special turnkey solution using robot-controlled measurements and Statistically Optimised Near-field Acoustic Holography (SONAH) has stabilised development time requirements and provided improved insights to build GN ReSound’s knowledge base.

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A Desktop NVH Simulator has vastly improved Commercial Vehicle Group’s customer relations and jury testing capabilities. The simulator was the latest addition to their range of Brüel & Kjær products that began when their R&D facility was commissioned in 2008. Back then, when it came to setting up a new lab, the combined experience of their commercial and construction vehicle experts led them to choose Brüel & Kjær to provide the equipment they need for world-leading NVH development of their automotive solutions.

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In 2007 Global Renewables was awarded a contract worth £2bn over 25 years to process the household waste of 1.4m people in Lancashire in the North of England.
Driven by the increasing costs and environmental damage of landfill, the contract required building two waste recycling facilities at Farrington and Thornton at a cost of £125M together. Each facility converts 530,000 tonnes of household waste into high quality compost per year.
Whilst the sites were located away from densely populated areas and intended to operate 24 hours per day, environmental issues around odour, air quality and particularly noise were key concerns to local residents.As a consequence noise limits were agreed and form part of the operating licence for each plant.

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Noise from large construction projects can be a nuisance for nearby communities. Vibration from activities like pile driving, concrete crushing and tunneling can also create nuisance but may also risk structural damage. Increasingly, both noise and vibration are significant factors surrounding a construction project. If not managed properly they can lead to project delays, further prolonging the nuisance and significantly increasing project cost. To help mitigate these risks, contractors are now using continuous noise and vibration monitoring to ensure that the impact from construction activity is kept within guidelines.

This paper looks at how continuous real time monitoring of noise and vibration can be used to help manage community impact and reduce the risk of structural damage. It will look at legislation and best practice both in Canada and in other parts of the world. Presenting the concept of environmental capacity it also shows how engaging communities, setting expectations and building trust can be effective way of mitigating impact.

The paper goes on to highlight new technology that is in use in Canadian construction sites which uses the approaches discussed above to help manage compliance and reduce risk.

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Ensuring the reliability of heating and refrigeration circuits, the Valliant Group’s Center of Competence uses vibration diagnostics to understand and predict damaging resonances in systems and components such as piping and compressors.

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Pusarpedal is an environmental laboratory under the Indonesian Environment Ministry, performing environmental quality testing and monitoring. It also verifies data from other laboratories and works to develop environmental laboratories at the provincial level.

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The object of this publication is to give the prospectives train gauge user a simple explanation of the basic theory and practice of measurement using strain gauges. lt will show how various factors, such as type of gauge,gauge material, measuring conditions and type of instrumentation can influence the results obtained.

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The Sound Answers/Brüel & Kjær partnership started in November 2006 when Sound Answers selected Brüel & Kjær as its hardware and software strategic partner. Sound Answers wanted to partner with a software/hardware manufacturer in the sound and vibration domain through which they could offer their services while enabling the partner to provide total solutions to customers. Brüel & Kjær was chosen for its test focus, reputation, best-in-class products, sales network, its strength in all its relevant markets and, most importantly, the management vision to provide a complete solution by leveraging consulting for pull-through product sales. Sound Answers President, Dr. Gabriella Cerrato, says, “Partnering with Brüel & Kjær was the best choice for both companies because of our similar vision and goals.”

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Linamar’s more than 45 years of experience as a manufacturer of precision metallic components and systems for the automotive industry has served them well. As a manufacturer and supplier of highly engineered solutions for the automotive market their design and manufacturing base numbers 39 plants and some 17000 employees worldwide. Based in Guelph, Ontario, Linamar is one of Canada’s largest automotive parts company. Linamar has partnered with Brüel & Kjær and works closely with us in the development of
Linamar’s products and automotive engineering solutions.

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Heat stress is a major problem in several working environments. Although technology has brought about remote control of industrial processes from airconditioned cabins, there are still many people who have to work in hot environments. Several methods for evaluation of heat stress have been presented In the literature.

This article describes the method of evaluation of heat stress by means of the WBGT -index, which has been standardized recently in the International Standard ISO 7243. Physiological reactions in hot environments are shortly described. Through the years several heat stress indices (both empirical and analytical) have been developed and used. The most common are also presented here.

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Carlisle Interconnect Technologies - a wiring and aerospace component manufacturer -  has benefitted greatly from its new range of testing capabilities after investing in a vibration test system, the engineering team at . As well as performing demanding tests for many engineers working in their group, they are now able to offer testing services for affiliated external companies

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A pass-by noise measurement is defined as the method of measuring the noise emission of a road vehicle under acceleration conditions, with various gear positions in a certain measurement range. These measurements are mandatory for automotive manufacturers in terms of product certification. For this reason, ISO (International Organization for Standardization) regulates the measurement and analysis procedures, as well as the reporting format.
Pass-by noise measurements are the most important part of troubleshooting in the mass production of cars, for example in the analysis of engine, intake and exhaust, and tyre noise. The pass-by noise measurement method is designed to meet the requirements of simplicity, as far as it is consistent with the reproducibility of the results.
The pass-by noise measurement should be performed in a large open space, for type approval of commercial vehicles, or measured during the official test station’s manufacturing stage. Therefore, it is very important that the certification of emission noise measurements is performed before mass production starts.
In some cases, however, pass-by noise measurements cannot be taken out in ‘the field’ because of bad weather or poor test-track conditions. In such cases, the indoor simulated pass-by noise measurement is often used. The indoor simulated pass-by noise measurement does offer a number of advantages such as good repeatability, flexibility, ease of use, etc., and is being considered as the conformance test, together with the field pass-by test, by ISO standard.

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Noise Scope, a PULSE-based beamforming system that includes a portable half-wheel array, was delivered to Nippon Expressway Research Institute Company Limited (NEXCO RI). This customised beamforming solution is used to measure noise in areas affected by traffic and road noise. These include residential areas, bridges, intersections, junctions, tunnels and motorway tollbooths. As a result, NEXCO-RI can optimise the design and construction of highways and their facilities to reduce the adverse effects of highdensity traffic.

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ディーゼルエンジンの音質を改善するために、いすゞ自動車はブリュエル・ケアーと共同で音質メトリクスマッピングを開発しまし
た。ラウドネスやシャープネス、ラフネスなど、音の知覚に基づいたパラメータ（音質メトリクス）を用い、音の特徴別に騒音源の
位置を特定できます。同時に、ディーゼルエンジンのどこから衝撃的な騒音が発生しているかを特定するために、「インパルシブネ
ス」の新しい計算アルゴリズムも開発しました。いすゞとブリュエル・ケアーのプロジェクトによって、ビームフォーミングと
SONAH（統計的最適化近距離場音響ホログラフィ）システムで使用できる、世界初の音質メトリクスマッピング用ソフトウェアが
誕生しました

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Using a simulator is unusual for a tier-one automotive supplier and helps to both develop components to exacting specifications, and communicate with customers throughout the development process.

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Volvo is increasingly moving its Noise, Vibration and Harshness (NVH) development into computer simulation and modelling, with less traditional prototyping. A well-established customer of Brüel & Kjær, Volvo benefits greatly from the value added to their systems in terms of the minimised downtime, optimised functionality, and assistance with new applications - thanks to their PULSE Software Maintenance and Support Agreement.

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This article investigates the capability of an array containing two parallel layers with 8 × 8 microphones in each layer and with 3 cm microphone pitch to measure sound intensity at low frequencies in sound fields with strong reactive or diffuse components. This is done basically by extending the concept of pressure-residualintensity (p-RI) index from two-microphone intensity probe measurements to array measurements and by estimation of that index based on both simulated and real measurements. Good agreement is achieved between p-RI indices obtained from simulated measurements and from real measurements in a large standing wave tube. It is shown that for typical array microphones it is essential to correct for the differing frequency responses, typically based on response data stored in the Transducer Electronic Data Sheets (TEDS) of the individual microphones.

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Recent years have seen the rise of vibration problems associated with structures which are more delicate and intricate, and machines which are faster and more complex. The problems have been coupled with demands for lower running costs and increased efficiency. Concern has also arisen about the effects of noise and vibration on people and on the working lifetime of manufactured items. Consequently, there has been a requirement for a greater understanding of the causes of vibration and the dynamic response of structures to vibratory forces. To gain such an understanding an accurate, reliable and versatile vibration transducer is required. In addition, advanced measurement and analysis equipment is often used. However, both the versatility and capability of such equipment would be wasted without an accurate vibration signal from a reliable vibration transducer.

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Les annees recentes ont vu la multiplication des problemes de vibrations associes a des structures plus delicates et a des machines plus rapides et plus complexes. ces probldmes sont ll6s aux exigences du marchd pour un mellleur rapport qualit6/prix. une attention particuligre est aussi portee sur les effets du bruit et des vibrations sur les hommes, et sur la dur6e de vie des produits manufactures. ll s'lmpose donc une meilleure compr€henslon des causes de vibratlons et des reponses dynamiques des structures aux forces vibratoires. A cet eftet, un capteur de vibrations pr6cis, fiable et versatile est requis. De plus, les appareils de mesure et d'analyse trds sophistiques qui sont souvent utilises sont inutiles sans signaux de vibrations precis venant d'un capteur fiable.