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Aquatic product processing is the process of transforming aquatic raw materials into products with shape, quality, and value, and weighing is the key link. As an important part of the marine industry, the development of aquatic product processing is promoted by marine engineering technology and marine equipment intelligence. With the continuous development of marine engineering technology and the continuous intelligence and automation of marine equipment, the application of dynamic weighing technology is increasingly extensive, and its position in the marine industry is also more and more important. Due to the lack of in-depth research in China, the stability and accuracy of the existing weighing sensors are poor, and there is no corresponding professional marine weighing equipment in our country. There are many challenges, such as the marine environment and ship shaking. This paper mainly introduces the background and types of ship weighing, as well as the advantages and disadvantages of existing equipment, and analyzes the technical characteristics of the weighing compensation algorithm and its application advantages in aquatic product processing. Finally, the relevant research and status quo at home and abroad are summarized. In order to solve the dynamic weighing under complex sea conditions, it is necessary to collect and analyze the weighing data under different sea areas, ship types, loads, and working conditions to provide a basis for the optimization and verification of the weighing compensation algorithm. Establishing a marine weighing database can improve the accuracy and reliability of aquatic product quality and provide data support for the development and utilization of marine resources. In order to look forward to the future aquatic product processing industry and other aspects, the marine ship-borne weighing technology is finally realized. [ABSTRACT FROM AUTHOR]

To obtain the weight information required for weight classification of golden pomfret and realize rapid and non- contact preprocessing. This research is based on the front and back projection images of multiple Golden pomfret, and an image processing algorithm is used to obtain the projected area, perimeter, long and short axes, etc. and is combined with artificially measured body length, body width, fin weight, head fin width, the width of the narrowest point of fishtail and other related data, through linear regression, curve estimation, principal component analysis, RBF neural network, and other methods build a weight prediction model and validate it. The results show that among the 14 weight prediction models established, the multiple linear regression model based on the image area, the proportion of fin weight, and the proportion of finless area have higher prediction accuracy, and the model ' s coefficient of determination is 0. 919. The coefficient of determination of the linear regression model based on the image area, image perimeter, long axis, and short axis is 0. 918. Among the established 9 principal component regression models, the quadratic regression model is the best, with a coefficient of determination of 0. 877 and a standard estimation error of 17. 094. The model is verified by modeling out- of-sample data. The correlation coefficient between the predicted value and the actual value of the regression model based on the image area, the proportion of fin weight, and the proportion of the finless area is 0. 944, the average relative error is 2. 43%, and the standard deviation is 2. 32%. The research results show that the quality prediction model of Golden pomfret based on machine vision technology has high reliability and can be applied to the quality classification of Golden pomfret. [ABSTRACT FROM AUTHOR]

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To improve the development of life-cycle multihazard-based design theory for high-performance structures in China, the research progress of this field was summarized and the research framework was systematically set up. The researches on the probabilistic occurrence models of individual hazard and multiple hazards were elaborated. The analytical models concerning the environmental effects on the time-variant deterioration of materials and structural component were summarized by taking the carbonization corrosion and wind induced fatigue as examples, which were conducive to guide the life-cycle performance assessment of high-performance structures subjected to multiple hazards. Moreover, the research status of the fragility analysis and the life-cycle cost based optimization design approach for high-performance structures were discussed in detail. The combined effects of multiple hazards and the lifetime deterioration of structural performance, which are neglected in the traditional specifications, can be rationally included in the life-cycle multihazard-based structural analysis and design methodology, which is of great significance for the development of building structural design. [ABSTRACT FROM AUTHOR]

Antarctic krill is not only rich in biological resources, but also has high utilization value. As a new protein resource, Antarctic krill will get more and more attention as the offshore fishery resources dwindle. But Antarctic krill is very small and grows in the distant Antarctic seas. Krill is rich in active enzymes and tends to deteriorate. As a result, it needs to be processed quickly on board. Therefore, the fishing and processing of Antarctic krill require higher cost and have more difficulty. In the 1960s, the development of krill industry was started from abroad, and China has begun the research on krill processing technology in recent years. Some preliminary research results have been obtained in process and equipment. Krill is often used to produce shrimp meat or to extract shrimp oil. Peeling is another effective method for the utilization of Antarctic krill. Previous research has shown that roller extrusion is one of the effective methods for the peeling of Antarctic krill. There are many factors that influence the effect of peeling in actual production, such as rotation speed, extrusion distance, and roller clearance. It is also affected by the wind and waves of the sea. The wind and waves sway the ship and affect the safety of navigation. These include the impact on personnel and the impact on equipment. The influence of sway on the equipment is reflected in the change of stability and processing effect. A composite laminates peeling equipment is developed to explore the effect of waves on the peeling results of krill. The performance of the equipment under different swing conditions in the sea was analyzed. Ships would have varying degrees of lateral sway and vertical sway during the voyage. The yield rate and residual rate of shrimp shells were measured and recorded. The roller was divided into 4 areas according to the length. The completion rate of peeling in different regions was analyzed. The experimental results show that the swing of the ship affects the yield rate and the residual rate of the shell. But the difference is not significant. Krill shell residue ratio rises to 1.07% when the longitudinal swing reaches 7°. And it rises to 1.64% when the lateral oscillation reaches 5°. The swing of the ship also has a certain effect on the completion rate of the peeling. The completion rate of peeling in the same area shows a decreasing trend, with the increase of swing amplitude. It is found that increasing the length of the roller can effectively alleviate the problem of the decrease of the peeling completion rate caused by the swing. The completion rate is greater than 95% when the roller length is about 1200 mm. The retention time has a great effect on the peeling effect. The completion rate of peeling of the krill that is stored for 2 h decreases significantly after being caught. And peeling completion rate reduces to 94% in the regional Ⅳ. The residual rate of shrimp shells increases correspondingly. The results can provide reference for the application and industrialization of Antarctic krill peeler. [ABSTRACT FROM AUTHOR]

The Antarctic krill is a marine organism with a large number. It has great value of development and utilization. As a new protein resource, Antarctic krill will get more and more attention since the offshore fishery resources are dwindling. Although the Antarctic krill has a high value of nutrition, it is hard to process because of its high fluorine content and strong enzyme activity. The krill has to be processed within 2 h on the ship after fishing in order to maintain its quality. Shelling is one of the effective methods to improve the quality of krill product. In previous studies peeling method was researched in order to get integral meat of Antarctic krill. Parameters such as body length and body weight of Antarctic krill that was just caught up were also measured. And we know that the peeling process conditions got from the response surface for Antarctic krill had a certain value in use and the method could be used on the ship. So the shelling prototype was developed and tested on the ship. In order to verify the krill shelling equipment and improve the production process, the research focused on the impacts of feeding rate, storage time and pre-cooling on shelling yield and residual rate, which would provide the bases for the practical production. The production process was considered carefully. Feeding speed was controlled by manpower in order to put the krill into a trough evenly. Then the krill would be pumped to the shelling machine after evenly mixing with water. The shrimp was put on the gauze for 2 min to filter the water after shelling, and then residual shells in shrimp were removed by manpower. The last processes were weighing, packaging and frozen. Test equipment unit was designed as 8 groups of rollers with reciprocating rotation. Yield was one of the most important indices for the evaluation of equipment ability, and residual rate was the other. The product quality of shrimp meat needed to be judged by sensory evaluation. The sensory evaluation team was made up of 5 seafarers who had a lot of experience of krill production on board. The comprehensive point was based on the integrity of shrimp, shell residue, plumpness and cleanliness. The results showed that the yield was about 24% and the residual rate was about 5%, and the shelling equipment was reliable. The yield of shelling from fresh Antarctic krill reduced slowly with the increasing of the feeding speed. It was relatively stable when the feeding speed was under 50 kg/h. And the residual rate was on the rise with the increasing of the feeding speed. When the feeding speed was higher than 60 kg/h, the residual rate of shrimp shell increased significantly. The krill with the storage time of less than 120 min could be used for production. Freshness is the most important factor in the quality of shrimp meat. Pre-cooling is an effective way to maintain shrimp quality. Frozen shrimp is not recommended to be used because the yield of shrimp meat will become lower significantly. [ABSTRACT FROM AUTHOR]