Hull Type Research Articles

Design and Experiment of a Soil-Covering and -Pressing Device for Planters

In response to the practical production challenges posed by the unreliable operation of the V-shaped squeezing soil-covering and -pressing device (VCP) for planters under clay soil conditions in Northeast China, incomplete seed furrow closure, and severe soil adhesion on pressing wheels, this study proposes a device with star-toothed concave discs for soil-covering and -pressing (STCP) with the aim of enhancing the soil-covering quality of planters. The main working principles of STCP were expounded, and its main structural and installation parameters were determined and designed. Based on bionics, with the dung beetle’s protruding head structure as the research object and UHMWPE as the material, an optimized protuberance-type bionic pressing wheel was designed. A Box–Behnken experiment was conducted by taking the width of the compression wheel, the spring deformation, and the installation angle as experimental factors, as well as the weight of the soil adhered to the surface of the pressing wheel (SW) and the soil compactness (SC) as the evaluation indicators. The optimal structural parameters of the pressing device were determined as follows: the width of the pressing wheel was 60.57 mm, the spring deformation was 55.19 mm, and the installation angle was 10.70°. The field comparison tests of soil covering performance showed that the star-tooth concave disc soil-covering device can effectively solve the problem of seed “hanging” and “drying”. The average covered soil weight of the star-tooth concave disc soil-covering device was 241.46 g, and the average covered soil weight of VCP was 223.56 g. Compared with VCP, the average covered soil weight of STCP increased by 8.01%. The variation coefficient of covered soil weight after the operation of the star-tooth concave disc soil-covering device was 3.71%, which was more uniform than VCP. The field comparison tests of soil-covering thickness showed that the uniformity of soil-covering thickness can be significantly improved by adding a star-tooth concave disc soil-covering device to VCP. The comparative tests of soil anti-adhesive showed that the convex hull type pressing wheels optimized by bionics had better soil anti-adhesive performance, and the soil adhesion weight was reduced by 43.68% compared with VCP. The field comparative tests of seedling emergence showed that the seedling emergence rate after STCP operation was 3.9% higher than that of VCP.

Effectiveness of Crew Boat Hull Form on Manouvering Performance

The condition of the crew boat is good hull shape with good operational conditions when maneuvering. In this case, the condition of the waveform at sea will have a significant impact on the ship’s motion. To provide the optimal type of hull, it was developed by conducting several simulations on the ship’s motion. Several simulation conditions were carried out, including analyses of ship speed, the shape of the waves formed, and ship maneuvering. At the simulation stage, several types of hulls were carried out, including the single U-hull, the single V-hull, the trimaran, and the catamaran. The simulation limits the length of the ship but not the width of the ship because the conditions in the multi-hull require sufficient space for its width, so that it can be ascertained that it provides effective and efficient results for the selection of the shape of the hull. The simulation analysis carried out provides a recommendation that the single V hull model gives good results compared to other types of hull selection for crew boat hulls.

Numerical Study on Resistance of Stepped Planing Hull

A stepped planing hull, also known as a step hull, is a hull modification that reduces the wetted surface area. Although this type of hull has proven effective in several ships, it is still rarely used. The step hull possesses numerous advantages that make it ideal for activities involving small and fast boats. However, regrettably, its full potential remains untapped at present. The purpose of this study was to identify the effect of variations in the angle of the step hull on resistance or drag. The study utilized the CFD method, and three hull configuration models were used at each change in hull step angle of 180º, 210º, 240º, and 270º. Configurations 1 and 2 have similarities in terms of rear hull length (600 mm), hull height (20 mm for configuration 1 and 30 mm for configuration 2), and deadrise angle (15° for configuration 1 and 20° for configuration 2). Configuration 3 has similarities with an 800 mm rear hull, 20 mm hull height, and 15° deadrise angle. It was found that as the Froude number increases, the coefficient of total resistance decreases. Conversely, as the Froude number increases, the resulting resistance also increases. The configuration with the highest resistance value corresponds to the alteration from configuration 2 with a hull step of 180°, and that the alteration from configuration 2 with a hull step of 270° corresponds to the configuration with the lowest resistance value. This study concludes that deadrise angle and the height of the step hull are the main factors that require careful consideration when designing ships that use a step hull. Therefore, this research provides an understanding of the step hull and can serve as a basis for the development of the step hull.

Quantaloidal Completions of Order-enriched Categories and Their Applications

By introducing the concept of quantaloidal completions for an order-enriched category, relationships between the category of quantaloids and the category of order-enriched categories are studied. It is proved that quantaloidal completions for an order-enriched category can be fully characterized as compatible quotients of the power-set completion. As applications, we show that a special type of injective hull of an order-enriched category is the MacNeille completion; the free quantaloid over an order-enriched category is the Down-set completion.

EFFECT OF CATAMARAN HULL TYPE ON OCEAN WASTE COLLECTION BEHAVIOR

In this paper an attempt has been made to assess how effective waste-collecting use catamaran ship with conveyor in the front. Numerical investigation based on Reynolds Averaged Navier Stokes (RANS) for predicting the flow pattern characteristics, velocity contour, and ship resistance. The focus of the present study is the impact of catamaran ship hull front shape on waste collection in calm water through the numerical methods. The three variations of the front of the hull used are symmetrical hull type, inner flat, and outer flat. It is done using speed variations of 1 to 4 knots. The results show inner flat hull catamaran has the smallest total resistance value than others. In addition, analysis of the flow pattern in front of catamaran shows that outer flat hull catamaran is the easiest to make waste closer to conveyor. From analysis of velocity contours shows that outer flat hull catamaran also has fastest to make the waste close to conveyor.

Study of Purse Seine Fishing Ship Trimaran Seakeeping with Axe-Bow and Without Axe-Bow Model Using Computational Fluids Dynamics

Maluku waters are dominated by extreme weather conditions with wave heights of 1-5 meters. Purse seine fishingvessel is one type of fishing vessel that has very poor transverse stability. One way to improve the stability of theship is to change the shape of the monohull ship to a ship with a trimaran hull type. This research was focused onexamining the movement characteristics of purse seine fishing vessels with trimaran hull type with Axe-Bowmodification on the bow and without Axe-bow, through computational fluid dynamics. The use of Axe-bow ontrimaran is able to significantly reduce RMS Pitch, which is an average of 13.35% smaller when compared to Trimaranwithout Axe-bow. On the RMS Heave Trimaran Axe-bow can reduce an average of 5.27% if the Trimaran is withoutAxe-bow. Furthermore, the Trimaran Axe-bow is also able to reduce the RMS Roll by an average of 3.98% comparedto the Trimaran without Axe-bow. The results of this study can provide an initial description of the advantages ofusing the Axe-Bow on the Purse seine fishing trimaran ship.

Identifying physical, chemical and biological characteristics to assess grain processing responses of barley as a trait for the selection of feed varieties for cattle

This study was conducted to evaluate the effects of barley hull type (hulled vs. hulless) and head type (two- vs. six-row) on kernel characteristics, particle size distribution (PSD), gas production (GP) kinetics and in vitro dry matter disappearance (DMD) in batch cultures. All barley grain was dry-rolled to a processing index (PI) of 0.80 and barley types were evenly distributed within each in vitro run. Kernel uniformity and PSD on 3.35-, 2.36-, 1.18-, 0.85-mm sieves, GP kinetics and DMD at 6 and 48 h of incubation were measured. For both hulless and hulled barley, two-row types tended to exhibit higher test weight, plumpness, ether extract, starch and β-glucan contents than six-row types. A hull type × head type interaction (P < 0.01) was noted for kernel uniformity and particles retained on 3.35- and 2.36 mm sieves. For both hulled and hulless barley, more (P < 0.05) kernels were retained on the 3.35 mm sieve for two- vs. six-row, but this pattern was the opposite on the 2.36-mm sieve, where six-row exceeded two-row. For rolled-hulled barley, more particles (P < 0.05) were captured on 3.35-mm sieve for two- vs. six row, whereas the opposite response was observed for the 2.36-mm sieve. In contrast, for rolled- hulless barley, more (P < 0.01) particles were captured on the 1.18 and 2.36 mm sieves, with a similar distribution between head types. The accumulative gas volume (GV, mL/g OM), GP rate, and average gas production rate (AGPR) were higher (P < 0.01) for hulless than hulled barley. However, the time when half of GV occurred (T1/2) was higher (P < 0.01) for hulled than hulless varieties. The DMD at 6 and 48 h of incubation were also higher (P < 0.01) for hulless than hulled barley. In general, GP kinetics and DMD at 6 and 48 h were lower (P < 0.01) for six- than two-row types, with the exception of T1/2 which was greater (P < 0.01) for six-row. The GP and DMD at 6 and 48 h were strongly correlated with finer particles. The results suggest that hull and head types can have a significant impact on the rate and extent of barley grain digestion. Differences in PSD of rolled barley along with the positive correlation between fine particles and rumen fermentation, presents an opportunity to select barley varieties that could enhance rumen function responses in addition to agronomic traits.

THERMAL BEHAVIOR OF COATED BIO-POLYMERS

When it comes to designing a mini-submarine, the most important questions are what it should look like to achieve the purpose for which it was built and what propulsion force is required to operate it at expected parameters. This paper aims to answer some of these questions using a numerical analysis designed to optimize the body shape using the Ansys CFX software package. The mini-submarine understudy is research one and it is equipped with eight thrusters. The optimization aims to choose an optimal body shape between the frame type which is the simplest, cheapest, easiest to execute and offers easy access to all components, and the closed hull type which is more compact has lower hydrodynamic resistance, but is difficult to execute, is expensive and difficult to access inside for interventions and inspection. The cases of study are incompressible turbulent flow for a complete submerged body, distinguished by the complexity of the form and the conditions under which the computation must be performed. The simulation will be done at several speeds, according to the known power of the thrusters in steady-state conditions. The results will be compared whit measuring data, analyzed, and presented comparatively base on hydrodynamic resistance and speed, but will be discussed the other criteria as well.

Design of a Semi-Submersible Tourism Ship for Bunaken Underwater Recreation in Manado, Indonesia

With a rapid increase in various number of marine tourism destinations, especially in The Bunaken National Park with the amount of tourists that has increased throughout the year rising by 23% for domestic tourists and 12% for international tourists between 2002 and 2018. Unfortunately, to enjoy the underwater scenery of The Bunaken National Park can access by diving and snorkeling which is not all tourist can do that. Furthermore, in order to support the marine tourism industry in Indonesia, a semi-submersible tourism ship was developed with a glass at the hull's bottom based on the standard spiral design and the safety standard established by the rules so the tourists can easily enjoy the underwater ecosystem. The concept design of bottom-glass ship with trimaran hull type is offered as a problem-solving in this paper. The final design of the main dimensions are length of overall (LOA): 23,1 meters, width (B): 8 meters, Draft (T): 2.22 meters but the maximum submerged up to 2,5 meters, speed of 10 knots, and passenger capacity of 44 persons.

Analysis of The Effect of Speed on Seakeeping and Ship Motion

Ship motion is the ability of a ship to survive at sea under any conditions. Therefore this capability is an essential aspect in terms of ship design. The shape of the hull dramatically influences the characteristics of the movement and operability of the ship itself. Vessel operability is the time at sea when the structure can still operate according to the established criteria and its correlation to the wave height where the requirements will be exceeded. In this study, an analysis of 3 degrees of freedom of translational movement and rotation of heave roll and pitch was carried out on the planing hull type fast boat model at regular waves with the parameters of body mass, gyration radius, damping, and others presented in the form of a Response Amplitude Operator (RAO) graphic image.

Analysis of The Effect of Speed on Seakeeping and Ship Motion

Ship motion is the ability of a ship to survive at sea under any conditions. Therefore this capability is an essential aspect in terms of ship design. The shape of the hull dramatically influences the characteristics of the movement and operability of the ship itself. Vessel operability is the time at sea when the structure can still operate according to the established criteria and its correlation to the wave height where the requirements will be exceeded. In this study, an analysis of 3 degrees of freedom of translational movement and rotation of heave roll and pitch was carried out on the planing hull type fast boat model at regular waves with the parameters of body mass, gyration radius, damping, and others presented in the form of a Response Amplitude Operator (RAO) graphic image.

Design of the Bengawan Unmanned Vehicle (UV) Roboboat: Mandakini Neo

Mandakini Neo is an autonomous vehicle that was designed and built by the students of the Universitas Sebelas Maret, which was included in the Bengawan Unmanned Vehicle (UV) Roboboat Team to compete in the annual international Roboboat competition of 2021. This competition requires participants to complete several missions; one of the main missions is to move through two gates made from four poles using full automatic navigation, in order to continue on with the other missions. To complete the course, we used Pixhawk and GPS to allow the ship to run automatically, while minimizing the ship’s movement tolerance. The use of Mission Planner software for monitoring, and also for color and shape image processing to help with the reading of objects, along with a sensor fitted on the ship, allowed the mission to be completed. Mandakini Neo was made with the capacity, speed, and comfort of the ship in mind, as well as the ship’s hydrodynamic performance, stability, volume, structural integrity, and construction cost. Following its development we conducted tests of stability, maneuverability, and seakeeping in order to achieve the smallest possible resistance rate; for this purpose, we used the Savitsky method. The manufacture of the ship also required the choosing of the material, the use of the sensor, and also selection of an appropriate system. Finally, the design that we developed was a ship with a catamaran hull type, for which the dimensions had already been calculated, and the proper materials decided, and simple electrical components were able to be obtained for the sensor and the system.

Effect of Monohull Type and Catamaran Hull Type on Ocean Waste Collection Behavior Using OpenFOAM

Ocean waste that continues moving in the water has been a problem until now. This has stimulated marine debris cleaning technology to emerge. This research sought to evaluate the effectiveness of waste collection using a monohull and catamaran fitted with a forward conveyor. The Reynolds Average Navier Stokes (RANS)-based numerical simulation research is used to predict flow pattern characteristics, velocity contour, wave pattern, pressure distribution, and ship resistance. The current research focuses on the impact of a round-bilge-type monohull and inner flat-type catamaran hull front shape on waste collection behavior by applying numerical methods. The multiphase solver numerical configuration supplied with OpenFOAM v2112 has been verified and validated using the Delft catamaran 372 with Froude numbers 0.3. The effect of free surface on resistance and flow characteristics was evaluated by comparing these two models. The results show the behavior of marine debris collection due to the flow characteristics of both models. The marine debris flows much more conveniently through the conveyor fitted in front of the catamaran model than in the monohull model. In addition, considering the front-side hull flow, the catamaran model is superior since marine debris is able to approach the ship easily. However, the monohull model is faster at bringing marine debris closer to the conveyor, particularly at the location in front of the conveyor.

3D Reconstruction &amp; Modeling of the Traditional Greek Trechadiri: “Aghia Varvara”

3D modeling techniques have grown increasingly prevalent in a variety of disciplines, including cultural heritage and ship design. The methodology used in the 3D reconstruction of a traditional Greek boat with the Trechadiri hull type named “Aghia Varvara” is presented in this study. The original boat was built in 1925 and is characterized as a modern cultural heritage monument by the Greek Ministry of Culture. The digital reconstruction of the boat is explained in detail, including 3D laser scanning and computer aided geometric design (CAGD), as well as the description of the 3D printing process. The boat’s 3D digital model has been used for the enrichment of the NAVS Project’s digital library, demonstrating the unique geometrical, typological, and cultural characteristics of Greek traditional shipbuilding, a living craft which listed on Greece’s National Inventory of Intangible Cultural Heritage.

CFD Analysis into the Resistance of Trimaran with Longitudinal Sidehull Adjustments

There has recently been a surge in demand for multi-hull vessels for military and commercial purposes. The need for multi-hull ships increase from the necessity to balance speed and cargo requirements. Among others, the trimaran is one such hull type. The current study performs a CFD resistance analysis for trimaran as a parameter range of feasible hull forms based on the NPL systematic series. The resistance of trimaran hull shapes are calculated using CFXTM, a commercial CFD code that belongs to ANSYS. The trimaran model was tested at one fixed transverse separation (S/L=0.2) together with 3 longitudinal separations, R/L=0, 0.25, and 0.5, at different Froude numbers (based on length) from 0.2 to 0.6. Testing on the individual hull is also carried out to quantify the effect of resistance interference on the trimaran configuration. The CFD simulation results indicate that the trimaran model with side hulls parallel to the stern (R/L=0) has the least resistance. The interference effect of resistance on Trimaran with R/L=0, 0.25, 0.5 are 2.8%, 4.6%, 6.8% as opposed to non-interference trimaran model, respectively. These findings provide an approach for appropriately selecting the trimaran model with longitudinal side hull configurations.

Tagging ocean soundscapes with machine learning and topological approaches

With a multitude of sources simultaneously contributing to the ambient ocean soundscape, it is important to disaggregate noise source contributions for better monitoring and assessing noise impacts. Our work adopts a modular set of neural networks and topological pipelines to analyze multiple representations of time-series samples of the ambient ocean noise. Specifically, a convolutional neural network (CNN) is used to broadly tag the presence of local shipping and marine mammal vocalizations from spectrogram representations. Multiple approaches are investigated using topological data analysis to predict a class label of the ship hull type or specific marine mammal species using the audio data as input. The datasets used in training, testing, and validation comprise hydrophone recordings across varying sensors and ocean environments to address the wide variation in ambient background noise and propagation paths. Algorithm performance is characterized by classification accuracy on labeled data. This approach demonstrates a generalized tagging cabilitility of the presence of marine mammals and local shipping activity.

Вплив промислових очищувальних рідин на анодно-окисне захисно-декоративне покриття отримане у розчині хромового ангідриду

The subject of research in this article is the anode-oxide coating of aluminum parts of the hull type of aircraft engine units and aircraft units under the influence of cleaning fluids of different nature and chemical compositions. The purpose of this work is to experimentally test, the effect of different cleaning fluids, under different operating conditions and on different equipment for the stability of the anode-oxide protective coating. Many experiments have been performed on three types of washing machines: jet and immersion washing machine, which works on all types of water-soluble detergents, washing machine cleaning in vacuum or low-pressure environment, uses modified alcohols or hydrocarbon solvents as a washing liquid, and specialized stand for cleaning parts with aviation kerosene, aviation fuel TS-1 or jet A-1. Flushing modes were, covered throughout the range of operation of this equipment. The operating conditions of engines and units and the need to use an anode-oxide coating of parts are determined. The main types of liquids for washing parts are considered. For each of the experiments a special technology of these studies was determined, as technological parameters, parameters that can change and affect the stability of the coating, were set the following temperature, detergent concentration, operating time, operating pressure in the detergent supply system. The change of each of these parameters was, carried out with the fixation of other technological parameters to determine the direct indicators of the impact of each of the parameters and to establish the growth of their impact on the anode-oxide coating. The conditions under which the coating is destroyed and the percentage of its damage from the total surface of the part are determined, and the quality of cleaning the part by particle size distribution and visual method was, also determined. It is determined that the greatest negative effects on the anodic oxide coating in the solution of chromic anhydride are acidic and alkaline water-soluble pore cleaning liquids, so they have the best quality of cleaning from contaminants, for which a range of indicators is determined at which the coating does not deteriorate.

ANALISA TITIK KRITIS GERAKAN ROLL KAPAL TRIMARAN UNTUK DIAPLIKASI PADA KAPAL IKAN PURSE SEINE

The marine fisheries catching and processing industry are considered vulnerable to the effects of extreme weather at sea. Global warming effects and El Nino and La Nina have a significant impact on the upwelling process, which impacts the lifestyle and environment of marine biota, including pelagic fish, which is one of the most important contributors to the shipping industry. Extreme weather conditions, with wave heights ranging from 1 to 5 meters, dominate the waters of Maluku. In extreme sea conditions, most fishers choose not to go fishing, not because there are no fish at the fishing grounds, but to avoid mishaps at sea. This research aimed to analyze the critical point of ship roll motion and ship stability. The hull shape employed in this study was a monohull fishing vessel and a trimaran fishing vessel with the same displacement of 21,1 tons. In extreme weather conditions, the Maxsurf software was used to analyze the ship's response, especially the critical point of the ship's roll motion. The I.M.O. Standard was utilized to calculate the ship's stability. The operational speed of the ship was v = 3 knots, with fluctuations in wave angle of incidence between 00 - 1800. Wave heights of 1,0; 2,0; 3,0, and 0,4 meters represent extreme weather conditions in Maluku waters' fishing grounds. The findings revealed that the trimaran hull type had better stability where the inclination angle of trimaran vessel stability was 480 while the monohull was 410. The trimaran fishing vessel was able to withstand a wave height of 3 meters with an inclination angle of 32,560. In comparison, the monohull fishing vessel was able to survive at a wave height of 2 meters with an inclination angle of 24,690. Monohull fishing vessel had a maximum limit of roll motion at wave directions 82 and 99 with a wave height of 3 m, and it reached at the critical point at angles of 43 and 138, at the height of 4 m. Meanwhile, the trimaran fishing vessel had a critical point at a wave angle of 760 and 1000 with a wave height of 4 meters. In the area between those two angles, monohull and trimaran fishing vessels will lose the balance (stability) of the roll motion, resulting in capsize.

Mapping QTLs for 1000-grain weight and genes controlling hull type using SNP marker in Tartary buckwheat (Fagopyrum tataricum)

BackgroundTartary buckwheat (Fagopyrum tataricum), an important pseudocereal crop, has high economic value due to its nutritional and medicinal properties. However, dehulling of Tartary buckwheat is difficult owing to its thick and tough hull, which has greatly limited the development of the Tartary buckwheat processing industry. The construction of high-resolution genetic maps serves as a basis for identifying quantitative trait loci (QTLs) and qualitative trait genes for agronomic traits. In this study, a recombinant inbred lines (XJ-RILs) population derived from a cross between the easily dehulled Rice-Tartary type and Tartary buckwheat type was genotyped using restriction site-associated DNA (RAD) sequencing to construct a high-density SNP genetic map. Furthermore, QTLs for 1000-grain weight (TGW) and genes controlling hull type were mapped in multiple environments.ResultsIn total, 4151 bin markers comprising 122,185 SNPs were used to construct the genetic linkage map. The map consisted of 8 linkage groups and covered 1444.15 cM, with an average distance of 0.35 cM between adjacent bin markers. Nine QTLs for TGW were detected and distributed on four loci on chromosome 1 and 4. A major locus detected in all three trials was mapped in 38.2–39.8 cM region on chromosome 1, with an LOD score of 18.1–37.0, and explained for 23.6–47.5% of the phenotypic variation. The genes controlling hull type were mapped to chromosome 1 between marker Block330 and Block331, which was closely followed by the major locus for TGW. The expression levels of the seven candidate genes controlling hull type present in the region between Block330 and Block336 was low during grain development, and no significant difference was observed between the parental lines. Six non-synonymous coding SNPs were found between the two parents in the region.ConclusionsWe constructed a high-density SNP genetic map for the first time in Tartary buckwheat. The mapped major loci controlling TGW and hull type will be valuable for gene cloning and revealing the mechanism underlying grain development and easy dehulling, and marker-assisted selection in Tartary buckwheat.

A 3 Ft Gurindam Unmanned Surface Vehicle (USV) Stability Hullform Performance

3 ft Gurindam Unmanned Surface Vehicle (USV) showed unmaximal performance when it tested on the water. Uncalm movement, unmaximal speed indicated that something need to be checked and make sure to the USV so that it can maximize the performance. The USV is owned by Politeknik Negeri Batam, it’s 3 feet long, with single hull type, fuel engine motor and almost 8kg weight. This research aims is to get the stability analytical data so that the researche can collected some data which is will used to maximize the USV performance. From the research it can concluded that the USV has a maximal GZ 9,56cm at 48.2 deg in mimimal weight and maximal GZ 8.88cm at 48.2 deg at the maximall weight of the ship. From this result, it can concluded that the more weight added on the fuel tank (front position) the more unstable condition of the ship. Or, it’s need a fixed ballast on the AP area to get the more stability on the USV. Hopefully this reasearh followed by the owner and tested so that the performace of the ship will be maximal.&#x0D;