scholarly journals Development trends of outboard launchers for unmanned underwater vehicles and marine underwater weapons from underwater carriers (based on materials from open publications)

2020 ◽  
Author(s):  
В.О. Боярчик ◽  
В.Г. Михлин ◽  
А.А. Румянцев ◽  
Р.А. Урусов
Keyword(s):  
Rapid Development ◽  
Underwater Vehicles ◽  
Technical Condition ◽  
Mineral Deposits ◽  
Development Trends ◽  
Unmanned Underwater Vehicles ◽  
Mining Sites ◽  
Special Place ◽  
Wide Range ◽  
Technical Solutions

Принимая во внимание бурное развитие морской подводной техники для разведки и добычи полезных ископаемых со дна Мирового океана, которое невозможны без широкого использования необитаемых подводных аппаратов (НПА), вопросы, связанные с их отделением от носителя, становятся, несомненно, актуальными. Среди широкой номенклатуры подводных аппаратов, используемых для этих целей, особое место занимают НПА торпедообразной формы. К основной их миссии относят вопросы разведки мест залегания полезных ископаемых, освещения подводной обстановки при проведении работ, а также вопросы контроля технического состояния оборудования, оснащения мест добычи ископаемых, а также охраны района. В статье анализируются тенденции развития забортных пусковых установок, на основе открытых зарубежных и отечественных публикаций (статей, патентов, рекламных буклетов). Рассмотрены известные технические решения забортных пусковых установок и намечены наиболее перспективные направления развития пусковых установок. Taking into account the rapid development of marine underwater equipment for exploration and mining from the bottom of the oceans, which is impossible without the widespread use of unmanned underwater vehicles (UUV), issues related to their separation from the carrier are undoubtedly relevant. Among the wide range of underwater vehicles used for these purposes, a special place is occupied by torpedo-shaped UUV. Their main mission includes issues of exploration of mineral deposits, an overview of the underwater situation during work, as well as issues of monitoring the technical condition of equipment, equipping mining sites, as well as protecting the area. The article analyzes the development trends of overboard launchers based on open foreign and domestic publications (articles, patents, advertising booklets). The well-known technical solutions of overboard launchers are considered and the most promising directions for the development of launchers are outlined.

scholarly journals Review on Unmanned Underwater Robotics, Structure Designs, Materials, Sensors, Actuators, and Navigation Control

2021 ◽  
Vol 2021 ◽  
pp. 1-26
Author(s):  
Javier Neira ◽  
Cristhel Sequeiros ◽  
Richard Huamani ◽  
Elfer Machaca ◽  
Paola Fonseca ◽  
...  
Keyword(s):  
Underwater Vehicles ◽  
Research Area ◽  
Underwater Robotics ◽  
Development Trends ◽  
Unmanned Underwater Vehicles ◽  
Control Techniques ◽  
Starting Point ◽  
Navigation Control

Since its beginning, around the 50s decade, until present days, the area of unmanned underwater vehicles (UUV) has considerably grown through time; those have been used for many tasks and applications, from bomb searching and recovery to sea exploration. Initially, these robots were used mainly for military and scientific purposes. However, nowadays, they are very much extended into civils, and it is not hard to find them being used for recreation. In this context, the present research is an effort to make a walkthrough of evolution in this area, showing a diversity of structure designs, used materials, sensor and instrumentation technologies, kinds and the number of actuators employed, navigation control techniques, and what is new in development trends. The paper gives a clear starting point for those who are initializing into this research area; also, it brings some helpful knowledge for those who already have experience.

scholarly journals AN AUTONOMOUS LOW-FREQUENCY BROADBAND HYDROACOUSTIC EMITTING STATION

2020 ◽  
Author(s):  
А.А. Пивоваров ◽  
И.О. Ярощук ◽  
А.Н. Самченко ◽  
А.Н. Швырев
Keyword(s):  
Data Transmission ◽  
Acoustic Pressure ◽  
Low Frequency ◽  
Underwater Vehicles ◽  
Immersion Depth ◽  
Navigation Systems ◽  
Frequency Range ◽  
Electromagnetic Transducer ◽  
Wide Range ◽  
Technical Solutions

Разработана и изготовлена автономная низкочастотная широкополосная гидроакустическая излучающая станция с электромагнитным преобразователем, развивающая акустическое давление до 2400 Па (188 дБ), приведенное к расстоянию 1 метра от оси излучателя, в диапазоне частот 420–520 Гц (по уровню −3 дБ) и глубиной погружения до 500 м. Примененные технические решения позволяют использовать станцию для широкого круга океанологических исследований, а также при построении систем навигации подводных аппаратов и передачи данных по гидроакустическому каналу. An autonomous low-frequency broadband hydroacoustic emitting station with electromagnetic transducer has been developed and manufactured, for developing acoustic pressure up to 2400 Pa (188 dB) measured a distance of 1 meter from the axis of the emitter in the frequency range 420–520 Hz (at −3 dB level) and immersion depth up to 500 m. The applied technical solutions allow to use the station for a wide range of oceanographic studies, as well as when construction of navigation systems for underwater vehicles and data transmission on the hydroacoustic channel.

scholarly journals Advanced Functional Materials Based on Nanocellulose for Pharmaceutical/Medical Applications

Pharmaceutics ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1125
Author(s):  
Raluca Nicu ◽  
Florin Ciolacu ◽  
Diana E. Ciolacu
Keyword(s):  
Rapid Development ◽  
Cellulose Nanofibrils ◽  
Functional Materials ◽  
Medical Applications ◽  
Bacterial Nanocellulose ◽  
Green Materials ◽  
Wide Range ◽  
In Vivo Cytotoxicity

Nanocelluloses (NCs), with their remarkable characteristics, have proven to be one of the most promising “green” materials of our times and have received special attention from researchers in nanomaterials. A diversity of new functional materials with a wide range of biomedical applications has been designed based on the most desirable properties of NCs, such as biocompatibility, biodegradability, and their special physicochemical properties. In this context and under the pressure of rapid development of this field, it is imperative to synthesize the successes and the new requirements in a comprehensive review. The first part of this work provides a brief review of the characteristics of the NCs (cellulose nanocrystals—CNC, cellulose nanofibrils—CNF, and bacterial nanocellulose—BNC), as well as of the main functional materials based on NCs (hydrogels, nanogels, and nanocomposites). The second part presents an extensive review of research over the past five years on promising pharmaceutical and medical applications of nanocellulose-based materials, which have been discussed in three important areas: drug-delivery systems, materials for wound-healing applications, as well as tissue engineering. Finally, an in-depth assessment of the in vitro and in vivo cytotoxicity of NCs-based materials, as well as the challenges related to their biodegradability, is performed.

scholarly journals Design of 3D Additively Manufactured Hybrid Structures for Cranioplasty

Materials ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 181
Author(s):  
Roberto De Santis ◽  
Teresa Russo ◽  
Julietta V. Rau ◽  
Ida Papallo ◽  
Massimo Martorelli ◽  
...  
Keyword(s):  
Physical Models ◽  
Cranial Bone ◽  
Head Model ◽  
Rigid Sphere ◽  
Element Analysis ◽  
Aliphatic Polyesters ◽  
Hybrid Device ◽  
Wide Range ◽  
Hybrid Devices ◽  
Technical Solutions

A wide range of materials has been considered to repair cranial defects. In the field of cranioplasty, poly(methyl methacrylate) (PMMA)-based bone cements and modifications through the inclusion of copper doped tricalcium phosphate (Cu-TCP) particles have been already investigated. On the other hand, aliphatic polyesters such as poly(ε-caprolactone) (PCL) and polylactic acid (PLA) have been frequently investigated to make scaffolds for cranial bone regeneration. Accordingly, the aim of the current research was to design and fabricate customized hybrid devices for the repair of large cranial defects integrating the reverse engineering approach with additive manufacturing, The hybrid device consisted of a 3D additive manufactured polyester porous structures infiltrated with PMMA/Cu-TCP (97.5/2.5 w/w) bone cement. Temperature profiles were first evaluated for 3D hybrid devices (PCL/PMMA, PLA/PMMA, PCL/PMMA/Cu-TCP and PLA/PMMA/Cu-TCP). Peak temperatures recorded for hybrid PCL/PMMA and PCL/PMMA/Cu-TCP were significantly lower than those found for the PLA-based ones. Virtual and physical models of customized devices for large cranial defect were developed to assess the feasibility of the proposed technical solutions. A theoretical analysis was preliminarily performed on the entire head model trying to simulate severe impact conditions for people with the customized hybrid device (PCL/PMMA/Cu-TCP) (i.e., a rigid sphere impacting the implant region of the head). Results from finite element analysis (FEA) provided information on the different components of the model.

scholarly journals Single and Double Infections with Wolbachia in the Parasitic Wasp Nasonia vitripennis Effects on Compatibility

Genetics ◽  
1996 ◽  
Vol 143 (2) ◽  
pp. 961-972 ◽  
Author(s):  
Marie-Jeanne Perrot-Minnot ◽  
Li Rong Guo ◽  
John H Werren
Keyword(s):  
Genomic Dna ◽  
Rapid Development ◽  
Parasitic Wasp ◽  
Pcr Amplification ◽  
Bacterial Strains ◽  
Nasonia Vitripennis ◽  
Larval Diapause ◽  
Wide Range ◽  
Reproductive Incompatibility ◽  
Infected Line

Abstract Wolbachia are cytoplasmically inherited bacteria responsible for reproductive incompatibility in a wide range of insects. There has been little exploration, however, of within species Wolbachia polymorphisms and their effects on compatibility. Here we show that some strains of the parasitic wasp Nasonia vitripennis are infected with two distinct bacterial strains (A and B) whereas others are singly infected (A or B). Double and single infections are confirmed by both PCR amplification and Southern analysis of genomic DNA. Furthermore, it is shown that prolonged larval diapause (the overwintering stage of the wasp) of a double-infected strain can lead to stochastic loss of one or both bacterial strains. After diapause of a double-infected line, sublines were produced with AB, A only, B only or no Wolbachia. A and B sublines are bidirectionally incompatible, whereas males from AB lines are unidirectionally incompatible with females of A and B sublines. Results therefore show rapid development of bidirectional incompatibility within a species due to segregation of associated symbiotic bacteria.

Cassava Processing in Sub-Saharan Africa: the Implications for Expanding Cassava Production

1994 ◽  
Vol 23 (3) ◽  
pp. 197-205 ◽  
Author(s):  
Felix Izu Nweke
Keyword(s):  
Food Security ◽  
Water Supply ◽  
Sub Saharan Africa ◽  
Wide Range ◽  
Intensive Use ◽  
Cassava Production ◽  
Sub Saharan ◽  
Processing Techniques ◽  
Technical Solutions ◽  
Poor Soil

Cassava makes an important contribution to improving food security and rural incomes in sub-Saharan Africa, as it is tolerant of drought and poor soil and its cultivation does not require much labour. However, the fresh roots are bulky and perishable and need to be processed before they can be marketed; processing also removes the cyanogens which make many varieties poisonous in their raw form. Cassava roots are turned into granules, flours, pastes and chips, with a wide range of flavours and appearances for different areas and markets. Many different processing techniques are used, some of which make intensive use of fuelwood while others require a plentiful water supply. These requirements, as well as the need for a good transport and marketing infrastructure, limit the expansion of cassava production in sub-Saharan Africa, but technical solutions are being found.

Experimental Study of Command Governor Adaptive Control for Unmanned Underwater Vehicles

2019 ◽  
Vol 27 (1) ◽  
pp. 332-345 ◽  
Author(s):  
Charita Darshana Makavita ◽  
Shantha Gamini Jayasinghe ◽  
Hung Duc Nguyen ◽  
Dev Ranmuthugala
Keyword(s):  
Experimental Study ◽  
Adaptive Control ◽  
Underwater Vehicles ◽  
Unmanned Underwater Vehicles

scholarly journals Comparative investigations in the effect of angle of attack profile on hydrodynamic performance of bio-inspired foil, (corrected)

2013 ◽  
Vol 10 (2) ◽  
pp. 99-108 ◽  
Author(s):  
J. A. Esfahani ◽  
E. Barati ◽  
Hamid Reza Karbasian
Keyword(s):  
Angle Of Attack ◽  
Underwater Vehicles ◽  
Hydrodynamic Performance ◽  
Profile Function ◽  
Flapping Foil ◽  
Propulsive Performance ◽  
Wide Range ◽  
Effective Angle ◽  
Thrust Production ◽  
Optimum Profile

In flapping underwater vehicles the propulsive performance of harmonically sinusoidal heaving and pitching foil will be degraded by some awkward changes in effective angle of attack profile, as the Strouhal number increases. This paper surveys different angle of attack profiles (Sinusoidal, Square, Sawtooth and Cosine) and considers their thrust production ability. In the wide range of Strouhal numbers, thrust production of Square profile is considerable but it has a discontinuity in heave velocity profile, in which an infinite acceleration exists. This problem poses a significant defect in control of flapping foil. A novel profile function is proposed to omit sharp changes in heave velocity and acceleration. Furthermore, an optimum profile is found for different Strouhal numbers with respect to Square angle of attack profile.DOI: http://dx.doi.org/10.3329/jname.v10i2.14229

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