In this paper, the forming principle, meshing features and tooth surface equation were introduced. And the modal parameters distribution of cylindrical gears with arcuate tooth trace was researched. The results show: 1. The modulus was the biggest impact factor for modal and natural frequency of cylindrical gears with arcuate tooth trace, then tooth width, and the radius of tooth line have the ...

Japanese Spanish mackerel ( Scomberomorus niphonius ) is an important fish species in the China Seas with wide distribution, extensive migration, and high economic value. This has been yielding fisheries production despite experiencing continuously fishing pressure conversion from gillnet to trawl harvesting. Meanwhile, changes life-history traits have observed, including earlier maturation sma...

The importance of plastic gears for modern industry is growing every year. The engineer sizing plastic gears has a very difficult task. There is no international standard available for the strength analysis. The only method publicly accepted is the German guideline VDI2545. In addition to a lack of calculation methods there is a need for measuring material properties. This paper shall give an o...

The tooth flanks of bevel gears with involute teeth are still cut using approximations such as Tredgold’s and octoid curves, while the geometry of the exact spherical involute is well known. The modeling of the tooth flanks of gears with skew axes, however, still represents a challenge to geometers. Hence, there is a need to develop algorithms for the geometric modeling of these gears. As a mat...

In the Norwegian oceanic fleet, whitefish onboard processing creates a great amount of rest raw materials. Cod heads are nutritious and good source for production high-quality marine peptides. Frozen cod heads, captured by trawl or longline, were evaluated based on lightness redness in neck cut to compare quality from different fishing gears. The subjected enzymatic hydrolysis. hydrolysates hav...

The recently available capability for the free-form milling of gears of various gear types and sizes — all within one manufacturing system — is becoming increasingly recognized as a flexible machining process for gears. This paper addresses the manufacturing and quality of gears made by free-form milling, with an added focus on the specific process properties of the parts. Finally, the potentia...

Based on the characteristics of fishing sector (multispecies and multi-gears) stock status main resources (overfishing overexploitation), some suggestions to improve sustainability demersal small pelagic fisheries in Mediterranean are proposed. In exploiting single or few species, such as pelagics deep-water red shrimps, adoption a management system based catch quota approaches is suggested. ca...

The Bizerte lagoon is characterized by its biological diversity and wealth of species with high commercial values such as cuttlefish, seabass, seabream, mussels, prawn, sole, fisheries provide employment for fishermen in the area. Indeed, artisanal fishing has been practiced decades using traps, nets, mobile gears straight nets lines. present paper focuses on diagnosis fisheries’ status this Th...

The length-weight relationships (LWRs) are one of the most useful parameters for fishery management and have importance in fisheries science. present study describes four freshwater fish species from Asi River system (Hatay, Turkey), namely Cobitis anabelae Freyhof, Bayçelebi & Geiger, 2018, levantina Krupp Moubayed, 1992, Oxynamecheilus hamvii (Krupp Schneider, 1991) namiri 1991). A total ...

Abstract Climate change and deoxygenation are affecting fish stocks on a global scale, but disentangling the impacts of these stressors from effects overfishing is challenge. This study was conducted to distinguish between climate mismanagement as possible causes for drastic decline in spawning stock size reproductive success cod ( Gadus morhua ) herring Clupea harengus Western Baltic Sea, when...