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Human-induced marine environmental noise, such as commercial shipping and seismic exploration, is concentrated in the low-frequency range. Meanwhile, low-frequency sound signals can achieve long-distance propagation in water. To meet the requirements of long-distance underwater detection and communication, this paper aims to propose an micro-electro-mechanical system (MEMS) flexible conformal hydrophone for low-frequency underwater acoustic signals. The substrate of the proposed hydrophone is polyimide, with silicon as the piezoresistive unit.

This paper proposes a MEMS heterojunction integration process for preparing flexible conformal hydrophones. In addition, sensors prepared based on this process are non-contact flexible sensors that can detect weak signals or small deformations.

The experimental results indicate that making devices with this process cannot only achieve heterogeneous integration of silicon film, metal wire and polyimide, but also allow for customized positions of the silicon film as needed. The success rate of silicon film transfer printing is over 95%. When a stress of 1 Pa is applied on the x-axis or y-axis, the maximum stress on Si as a pie-zoresistive material is above, and the average stress on the Si film is around.

The flexible conformal vector hydrophone prepared by heterogeneous integration technology provides ideas for underwater acoustic communication and signal acquisition of biomimetic flexible robotic fish.

The purpose of this paper is to improve the hydraulic efficiency without changing the overall dimension. The blade profile optimization design of the aero-centrifugal pump based on the biharmonic equation surrogate model has been studied.

First of all, Bezier curves and linear function are used to control the annular angle distribution and the stacking angle of blade profile under the MATLAB platform. Grid independence analysis has been studied to find the finest mesh scheme. After the precision comparison of test data and computation fluid dynamics 15 sets of design parameters are carried out as the boundary condition of the biharmonic equation. The efficiency surrogate model of the biharmonic equation is constructed via iteratively solving of a discrete difference equation. The other two surrogate models of response surface model (RSM) and radial basis function neural network surrogate model (RBFNNSM) are compared with the biharmonic equation surrogate model by the standard of modified complex correlation coefficient R² and root mean square deviation (RSME). Finally, the artificial fish swarm algorithm has been used to find the global optimal design parameters with the objective function of highest efficiency.

The results show that the design parameters code conversion method can reduce the number of optimization parameters from five to three, makes the design space become a cube, and compared with RSM and RBFNNSM, the biharmonic equation surrogate model has higher precision with R² is 0.8958, RSME is 0.1382. The final optimum result of AFSA is at the point of [1 −1 −1]. The internal flow field analysis shows that after optimization the outlet relative velocity becomes more uniform and the wake effect has been significantly decreased. The hydraulic efficiency of the optimized pump is about 59.45 per cent increasing 5.4 per cent compared with a prototype pump.

This study developed a new method to optimize the design parameters of aero-centrifugal pump impeller based on biharmonic equation surrogate model, which had a good agreement with experimental values within just 15 sets of the original design. The optimization results shows that the method can improve the hydraulic efficiency significantly.

Language may be a treasured heritage of small comunities, all that is left to bind them together. It is often a matter of national or regional pride, keeping alive a tongue dead centuries past everywhere else; in an area of the Grisons forty thousand Swiss speak the Latin Romansch, the tongue spoken by the citizens of ancient Rome, and nowhere else in the world is it heard. There are so‐called official languages; in the councils of Europe, it has always been French, which is the official language of the European Economic Community; this means, of course, that all EEC Directives and in due course, judgments of its courts, will be first delivered in French.

A practical fisherman or fishmonger has no difficulty in recognising the different members of the cod family. To the layman (and most public analysts and inspectors of food and drugs are perhaps to be included in this category) the problem is less easy. But if a sample includes (or consists of) a thick sectional slice complete with skin, its identification will be assisted by reference to the following table. Special importance should be attached to the black and strongly marked lateral line of the haddock, and to the “specks” to be seen with the aid of a small lens, or even with the naked eye, on each of the scales of the hake.

Contemporary literature reveals that, to date, the poultry livestock sector has not received sufficient research attention. This particular industry suffers from unstructured supply chain practices, lack of awareness of the implications of the sustainability concept and failure to recycle poultry wastes. The current research thus attempts to develop an integrated supply chain model in the context of poultry industry in Bangladesh. The study considers both sustainability and supply chain issues in order to incorporate them in the poultry supply chain. By placing the forward and reverse supply chains in a single framework, existing problems can be resolved to gain economic, social and environmental benefits, which will be more sustainable than the present practices.

The theoretical underpinning of this research is ‘sustainability’ and the ‘supply chain processes’ in order to examine possible improvements in the poultry production process along with waste management. The research adopts the positivist paradigm and ‘design science’ methods with the support of system dynamics (SD) and the case study methods. Initially, a mental model is developed followed by the causal loop diagram based on in-depth interviews, focus group discussions and observation techniques. The causal model helps to understand the linkages between the associated variables for each issue. Finally, the causal loop diagram is transformed into a stock and flow (quantitative) model, which is a prerequisite for SD-based simulation modelling. A decision support system (DSS) is then developed to analyse the complex decision-making process along the supply chains.

The findings reveal that integration of the supply chain can bring economic, social and environmental sustainability along with a structured production process. It is also observed that the poultry industry can apply the model outcomes in the real-life practices with minor adjustments. This present research has both theoretical and practical implications. The proposed model’s unique characteristics in mitigating the existing problems are supported by the sustainability and supply chain theories. As for practical implications, the poultry industry in Bangladesh can follow the proposed supply chain structure (as par the research model) and test various policies via simulation prior to its application. Positive outcomes of the simulation study may provide enough confidence to implement the desired changes within the industry and their supply chain networks.

The Commission appointed jointly by the World Health Organization and the Food and Agricultural Organization continues to plod its weary way towards the establishment of Codex standards for all foods, which it is hoped will eventually be adopted by all countries, to end the increasing chaos of present national standards. We have to go back to 1953, when the Sixth World Health Assembly showed signs of a stirring of international conscience at trends in food industry; and particularly expressed “the view that the increasing use of various chemical substances had … , created a new public health problem”. Joint WHO/FAO Conferences which followed initiated inter alia international consultations and the setting up of the Joint FAO/WHO Codex Alimentarius Commission.

Three events of significance to this country took place in 1899 – the British Food Journal was launched, Australia retained the Ashes, and the Boer War hostilities commenced. If challenged on the order of their importance, cricketers and Empire‐builders may be excused their preference. However, looking at it purely from the standpoint of pro bono publico, the dispassionate observer must surely opt for the birth of a certain publication as being ultimately the most beneficial of the three.

Those who move among the people with their eyes open will not doubt that the number of non‐smokers is increasing, but mostly among older adults. Sales of cigarettes, despite the ban on advertising and the grim warning printed on packets, do not reflect this however, which can only mean that those who still smoke are the heavy smokers. This is a bad sign; as is the fact that youngsters, including a high percentage of those at school, openly flaunt the habit. The offence of using tobacco or any other smoking mixture or snuff while handling food or in any food room in which there is open food (Reg. 10(e)), remains one of the common causes of prosecutions under the Food Hygiene Regulations; it has not diminished over the years. The commonest offenders are men and especially those in the butchery trade, fishmongers and stall‐holders, but, here again, to those who move around, the habit seems fairely widespread. Parts of cigarettes continue to be a common finding especially in bread and flour confectionery, but also in fresh meat, indicating that an offence has been committed, and only a few of the offenders end up in court. Our purpose in returning to the subject of smoking, however, is not to relate it to food hygiene but to discuss measures of control being suggested by the Government now that advertising bans and printed health warnings have patently failed to achieve their object.

The earliest law of the adulteration of food imposed divisions among the local authorities of the day in functions and enforcements; most of the urban and rural sanitary authorities possessed no power under the law. Provisions dealing with unfit food — diseased, unsound, unwholesome or unfit for human food — were not in the first sale of food and drugs measure and there duties were wholly discharged by all local authorities. Rural sanitary authorities were excluded from food and drugs law and boroughs and urban authorities severly restricted. Enforcement in the rural areas was by the county council, although local officers were empowered to take samples of food and submit them for analysis to the public analyst. Power to appoint the public analyst for the area was the main criterion of a “food and drugs authority”. The Minister had power to direct an authority with a population of less than 40,000 but more than 20,000 to enforce the law of adulteration.