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Multiple three-phase machines have become popular in recent due to their reliability, especially in the ship and airplane propulsions. These systems benefit greatly from the robustness and efficiency provided by such machines. However, a notable challenge presented by these machines is the growth of harmonics with an increase in the number of phases, affecting control precision and inducing torque oscillations. The phase shift angles between winding sets are one of the most important causes of harmonics in the stator currents and machine torque. Traditional approaches in the study of triple-three-phase or nine-phase machines mostly focus on specific phase shift, lacking a comprehensive analysis across a range of phase shifts. This paper discusses the current and torque harmonics of triple-three-phase permanent magnet synchronous machines (PMSM) with different phase shifts. It aims to analyze and compare the impacts of different phase shifts on harmonic levels.

Abstract For taking counter measures in advance to prevent accidental risks, it is of significance to explore the causes and evolutionary mechanism of ship collisions. This article collects 70 ship collision accidents in Zhejiang coastal waters, where 60 cases are used for modeling while 10 cases are used for verification (testing). By analyzing influencing factors (IFs) and causal chains of accidents, a Bayesian network (BN) model with 19 causal nodes and 1 consequential node is constructed. Parameters of the BN model, namely the conditional probability tables (CPTs), are determined by mathematical statistics methods and Bayesian formulas. Regarding each testing case, the BN model’s prediction on probability of occurrence is above 80% (approaching 100% indicates the certainty of occurrence), which verifies the availability of the model. Causal analysis based on the backward reasoning process shows that H (Human error) is the main IF resulting in ship collisions.

Electrified vehicles represent mobility’s future, but they impose challenging and diverse requirements like range and performance. To meet these requirements, various components, such as battery cells, electric drives, fuel cells, and hydrogen vessels need to be integrated into a drive and storage system that optimizes the key performance indicators (KPI). However, finding the best combination of components is a multifaceted problem in the early phases of development. Therefore, advanced simulation tools and processes are essential for satisfying the customer´s expectation. EDAG Engineering GmbH has developed a flat storage platform, which is suitable for both, BEV and FCEV. The platform allows for the flexible and modular integration of batteries and hydrogen vessels. However, package space is limited and the impact of the design choices regarding the vehicle’s KPI need to be considered.

With the increasing demand for efficient & clean transport solutions, applications such as road transport vehicles, aerospace and marine are seeing a rise in electrification at a significant rate. Irrespective of industries, the main source of power that enables electrification in mobility applications like electric vehicles (EV), electric ships and electrical vertical take-off & landing (e-VTOL) is primarily a battery making it fundamentally a DC system. Fast charging solutions for EVs & e-VTOLs are also found to be DC in nature because of several advantages like ease of integration, higher efficiency, etc. Likewise, the key drivers of the electric grid are resulting in an energy transition towards renewable sources, that are also essentially DC in nature. Overall, these different business trends with their drivers appear to be converging towards DC power systems, making it pertinent.

The purpose of this SAE Recommended Practice is to provide guides toward standard conditions for operating marine hydraulic transmissions where push-pull cable control is applicable. For control cable information see SAE J917.

The purpose of this SAE Recommended Practice is to provide guides toward standard conditions for operating marine engine throttles (gasoline or diesel) where push-pull cable control is applicable. For control cable information see SAE J917.

Mild steel and AISI 304 L have gained widespread usage across diverse industries, such as naval vessels, boilers, aviation, and automobile sector, due to their ready availability and distinct attributes. Fusion welding techniques have been employed to join this alloy, which is known for its specific qualities. The strength of welded joints is directly proportional to a certain percentage of the strength exhibited by the base materials. However, the welding process becomes intricate when dissimilar steels need to be joined. In such cases, achieving consistent and reliable welding become a challenge. Therefore, meticulous attention is required in the selection of electrodes, filler wires, and other operational parameters, such as current, voltage, and shielding gas. Among the solid-state joining methods, FW (Friction Welding) stands out as an excellent approach to achieving robust joints. This technique ensures strong joint formation.

SDVs redefine OEM, supplier relation- ships and deliver new feature CES 2024 offers a busy look at the software-defined-vehicle future Tuning-up AI's 'understanding' to make safer ADAS, AVs Kognic's advanced interpretation of sensor data helps artificial intelligence and machine learning recognize the human thing to do. Tremec-trification Tremec cranks up electric-drive innovation as the logical extension of its transmission-making expertise.

Amphibious vehicles with both land and water navigation functions have extremely high application value in the military and civilian fields. In order to fully utilize the wheel driving force and ensure the smooth landing of the amphibious vehicle driven by four wheel hub motor, an acceleration slip regulation (ASR) is designed under the condition of landing from water. First, the road friction coefficient is identified based on the back propagation neural network (BPNN). Then, utilizing the improved Burckhardt model, the current optimal slip ratio is calculated from the identified road friction coefficient. Finally, the ASR under the condition of landing from water is designed based on radial basis function (RBF) single neuron adaptive PID control algorithm. By analyzing the process of amphibious vehicles transitioning from water to land, a typical working condition for amphibious vehicles landing is established, and a joint simulation is conducted using CarSim/Simulink.

This SAE Standard establishes a uniform test procedure and performance requirement for limiting the maximum speed of a personal watercraft.

This SAE Standard specifies basic tolerances and dimensions for inboard propeller-shaft ends, propeller hubs and keyways for shaft sizes 3/4 in (19 mm) through 8 in (203 mm).

Abstract The sinking and trimming of the hull in the channel would directly affect the handling and navigation safety of the ship. In view of the ship sinking, a series of empirical formulas to estimate the subsidence have been put forward for vessel in spacious shallow water areas. However, most of the equations are based on seagoing vessels. They are not suitable for inland ships with small scales, shallow drafts, and narrow navigation width. Till now, research on ship squat in intermediate channel has not yielded more practical results. Here, a generalized physical model is used to study the sinking of 500t class ships in restricted intermediate channel under different channel widths, water depths, and speeds. The main factors affecting the squat are analyzed, the empirical relation is compared with the measured squat. The Barrass equation is modified, and the calculation relation of the settlement suitable for inland river ships is proposed.

This document defines a set of standard application layer interfaces called JAUS Mobility Services. JAUS Services provide the means for software entities in an unmanned system or system of unmanned systems to communicate and coordinate their activities. The Mobility Services represent the vehicle platform-independent capabilities commonly found across all domains and types of unmanned systems (referred to as UxVs). At present, over 15 services are defined in this document many of which were updated in this revision to support Unmanned Underwater Vehicles (UUVs).

To understand the effect of discharge frequency and discharge energy of dielectric barrier discharges (DBD) on the flame kernel development process, the observation of the discharges and ignition trials were performed in a constant volume vessel. Results showed that the energy of DBD released during a single cycle of discharge decreases, but the power of the discharges increases with the frequency increases. The ignition probability improved and the time for the flame propagation decreased under high frequency because the power of the discharges efficiently rises the local gas temperature near the electrodes.

This study is performed to experimentally examine the effects of hydrogen addition and turbulence on the ignition and the flame-kernel development characteristics in isotropic and homogeneous turbulence for methane or propane mixtures. First, in order to investigate the ignition and flame-kernel development in quiescence, the minimum ignition energy MIE and the relationship between the flame radius and the burning velocity of meso-scale laminar flames are examined by using sequential schlieren photography in a constant volume vessel. Then, the properties of MIE are examined for three turbulence level. Additionally, the transition region of MIE could be summarized by using the proposed turbulent Karlovitz number based on the burning velocity of the meso-scale flame in quiescence.

As an efficient hydrogen carrier, ammonia itself is also a promising zero-carbon fuel that is drawing more and more attention. As the combustion of pure ammonia is hard to achieve on SI engines, in this study, spark- ignited micro-gasoline-jet was utilized to ignite the premixed ammonia/air mixture in a constant volume combustible vessel at different premixed ammonia/air excess air coefficient and backpressure (represented by ammonia partial pressure). The flame image was captured by a high-speed camera and the transient pressure change in the vessel was measured by an engine cylinder pressure sensor.

This SAE Aerospace Standard (AS) defines a set of standard application layer interfaces called JAUS UMV Services. JAUS Services provide the means for software entities in an unmanned system or system of unmanned systems to communicate and coordinate their activities. The UMV Services represent the platform-specific capabilities commonly found in UMVs and augment the Mobility Service Set (refer to AS6009) which is platform-agnostic. At present, 12 services are defined in this document. While these services are presented alphabetically within this document, they also can be logically categorized as: Platform Description Services: This service provides information about the vehicle platform, including mobility limits and geometric properties: ○ Platform Specification Service. Propulsion and Driver Services: These services provide the control and monitoring capabilities to the vehicle’s propulsion system(s).