Naval Warship Research Articles

Towards a Reflective Stance of Honor and Dignity – An Inquiry into the Use of Force by Analyzing the US Navy’s Crossing the Line Ritual

ABSTRACT In this article, I examine the meaning of the use of force for military professionals by analyzing the US Navy’s Crossing the Line ceremony. Ambiguity surrounds the initiation ritual for crossing the equator onboard naval warships, especially as it comes to its form prior to the late 1990s. All the while, the US Navy has maintained that the ceremony is part of a long tradition for teaching the values of honor, commitment and courage. Inspired by Max van Manen’s approach to phenomenological writing ([1984]. “Practicing Phenomenological Writing.” Phenomenology + Pedagogy 2 (1): 36–69; [2016]. Writing in the Dark: Phenomenological Studies in Interpretive Inquiry. London: Routledge), I explicate the idea that the ceremony, in its former form, did indeed teach the value of honor, but through inversion, acting out the worst possible behavior imaginable for military professionals in the form of a black mass, while the ceremony in its current form teaches the value of individual dignity as a professional obligation. The inquiry concludes with a reflective stance of honor and dignity as moral principles for enabling and constraining the use of force. Derived from the experience of a particular military practice, the stance also has general significance, helping navigate the line between thoughtlessness and thoughtful actions within a social framework, not unlike the just war tradition.

Liquor Rations and Labour Management in the Nineteenth-Century Atlantic World

Abstract A striking yet underexamined system of labour management circulated between land and sea in the nineteenth-century Atlantic world: the use of liquor rations to stimulate worker productivity. Turning to the British naval warship and the American slave plantation, this article depicts how labour supervisors in both settings relied on carefully regulated quantities of alcohol to extract more labour from their workforces. Even as Anglo-American temperance activists called for sobering up the working classes, many naval commanders and slaveholders held firm to the belief that managed intemperance was an essential tool for mobilizing workers. The study of liquor rations and the arguments endorsing their distribution helps to reveal how a spectrum of coercive labour practices swept through the Atlantic world amid the emergence of an industrial capitalist order. Zooming in on the history of these rations enables us to discern labour extraction strategies that operated between the poles of violent coercion and market-based exploitation, and that animated vital sectors of the Atlantic economy during the nineteenth century.

Team orienteering with possible multiple visits: Mathematical model and solution algorithms

This study addresses a new team orienteering problem in which each point can be visited possibly multiple times with decreasing scores. The problem is to determine a set of routes from a starting to a finishing point within an allowed travel time limit for the objective of maximizing the total collected score. A mixed integer programming model is developed to represent the problem mathematically. Then, due to the complexity of the problem, a basic iterated local search (ILS) algorithm is proposed that incorporates the ordinary perturbation and local search operators. Then, it is improved in two ways: (a) an extended ILS algorithm with multi-visit based local search operators and (b) a hybrid ILS algorithm with a simulated annealing technique to permit non-improving moves in the local search step. To test the performance of the ILS algorithms, computational experiments were done on modified benchmark instances under the cases of linear, convex and concave score decreases, and the results show that the hybrid ILS algorithm improves the others significantly and also gives near optimal solutions for small sized test instances. Finally, a case study was done for a naval warship reconnaissance operation, and the results are reported.

Efficiency Improvement of Friction Stir Welding Parameters on AZ91 Magnesium Alloy Joints

Abstract: Friction Stir Welding (FSW) is a solid-state welding that permits an intensive formof parts and geometries to be welded with great nature of joints. The use of high-quality Magnesium alloys is extending in shipbuilding industry, particularly for the advancementof naval warships, cruise ships, littoral surface craft and merchant ships. FSW advancementhas been seemed to have various focal points for the exploitation of Magnesium alloys structures, as it is a minimal effort welding process. The objective is to come across the optimum levels of the process parameters in which it yields maximum tensile strength andbetter hardness. A three-factor, three-level design is utilized for optimizing the FSW process parameters and a Taguchi L9 orthogonal array experimental set up is used to anticipate the responses. The system parameters considered are Rotational speed, Transverse speed and the Tool tilt angle. The Friction stir welding is processed for butt joining of Magnesium alloys (AZ91) plates with 6 mm thickness. Tensile testing is attempted on dog-bone kind test specimen for Magnesium alloys. Analysis of Variance (ANOVA) has been used to analyze the effect of different parameters regarding the responses. The microstructural attributes of the welded segments, including base metal, heat affected zone (HAZ), Thermo Mechanically Affected Zone (TMAZ) and Stir Zone (SZ) are examined through Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX) analysis carried out to quantify the chemical element allocation at the weld interface. The observed optimum condition for Magnesium alloys (AZ91) is 560 rpm, 60 mm/min and 1 degree.

Zeeland Privateering Captains During the Fourth Anglo-Dutch War, 1780–1784

During the Fourth Anglo-Dutch War (1780–4) the fleet of the Dutch Republic was no match for the numerically far greater British navy. Her merchant ships were taken and the navy was forced to protect the home waters and stay in their own ports. In their own numbers as well as those of their captured prizes, Zeeland privateer captains lagged far behind the successes of earlier wars. Nevertheless, they received a heroic reception; something that had not occurred in previous wars to such an extent. Only 16 privateering captains were commissioned by the Zeeland Admiralty, yet in less than two years they captured 72 prizes and ransomed another 51 ships. The proceeds of the part which is known amounted to 514,389 guilders, making the total an estimated 2.44 million guilders. The omnipresence of British privateers and naval warships in the English Channel and North Sea made it a dire necessity for Dutch privateers to ransom, rather than capture prizes; this was something never done before on such a large scale. For decades the Dutch Republic had lived in peace, so the Zeeland privateering captains lacked experience. Nearly 30 per cent of them were of foreign origin, mainly French and American.

Identification of Multiple “Space Cohorts” Based on Ventilation Parameters: A Novel Strategy to Combat Airborne Pathogens on Naval Warships

Identification of Multiple “Space Cohorts” Based on Ventilation Parameters: A Novel Strategy to Combat Airborne Pathogens on Naval Warships

A computational study on air-entrainment and pressure distribution for natural convection cooling of a hybrid IRS device

The infrared suppression (IRS) device is an essential component of a naval warship, which passively cools the hot flue gas issuing out of the engine exhaust so as to suppress the infrared emissions. In this work, the natural convection cooling of the hot funnels of a hybrid-type IRS device has been numerically investigated in a finite volume framework by varying the diameter ratio (DR) and the Rayleigh number (Ra) in the range of 1.025 ≤ DR ≤ 1.5, and 1010≤Ra≤1012, respectively. It is observed that the Nusselt number as well the air entrainment ratio augments with the Rayleigh number. However, we noticed an initial increment in the Nusselt number with DR, and thereafter decreases marginally with a further increase in diameter ratio after attaining a peak. An optimum diameter ratio (DR = 1.1) has been obtained for the maximum heat transfer from the funnel walls. At the entry of the base and third funnel, intense suction pressure is induced, whereas the pressure recovers throughout the remaining portions of the IRS device. The influence of air entrainment on the flow and heat transfer phenomenon has been explained by delineating temperature contours, velocity vectors, and streamlines for different representative cases of the computational study. In addition, we nonlinearly regressed the computational data to propose an empirical correlation for the average Nusselt number. Furthermore, the estimation of cooling time has been done through lumped capacitance model.

Analysis Of Fuel Installation System Design At The Enviromental Of Naval Base

The fuel installation system is necessary to support the Indonesian Naval ships to carry out operations. The current condition in the field is that Second Fleet Command does not yet have a fuel installation system. So far, to support Indonesian Naval Warship in carrying out operations using Pertamina's fuel installation pipes which are directly distributed from Pertamina's bunker. As a result, the Navy has become very dependent on Pertamina's performance and this is quite an obstacle. Therefore, the author has an idea to design a fuel installation system that must be owned by the Navy, especially in the Second Fleet Command work area. In this final project, the fuel pipe installation system planning is first carried out starting from the bunker, piping, fittings, and support as a support for the installation based on a standard pipe installation design with a flow capacity of 100 kL/hour. The next stage is the calculation of the head which includes the head loss along the pipe due to friction between the fuel and the surface along the pipe and the head loss due to fittings in the installation so that the total head value of the installation will be obtained. In addition to manual calculations, numerical calculations were also carried out using pipe flow expert v5.12 software. The next step is to determine the power required for both pumps and motors to overcome the installation head and flow capacity designed and select the appropriate pump.

Navy En-Route Care in Future Distributed Maritime Operations: A Review of Clinician Capabilities and Roles of Care

Objective As the United States Navy transitions from Operation Iraqi Freedom/Operation Enduring Freedom to preparing for a near-peer competition, an increasing focus of wartime strategy relies upon a network of distributed naval assets for total sea control, known as Distributed Maritime Operations (DMO). Historically, embedded medical personnel have provided care at sea in times of war. Recent reviews of shipboard and evacuated mass casualty incidents have alluded to weaknesses in the existing Navy Medicine approach that will require advances in care provision to sustain high-quality care that would benefit from industry and civilian academic collaboration. To gain input from civilian prehospital expertise and insight, the current DMO and Navy En-Route Care (ERC) systems must be plainly described for non-Navy military and civilian leaders, clinicians, and researchers to understand. Methods N/A Results In this review, we translate US Navy structure and vernacular into common civilian and non-Navy language, describe the maritime role-tiered ERC system, elucidate the medical assets on each naval warship, and discuss clinician levels and capabilities while deployed to help communicate the inherent challenges of US Navy maritime medical care during routine operations, casualty treatment, stabilization, and evacuation. Conclusions We describe the roles of care, clinician levels, and medical assets within the Navy ERC system for researchers and military leaders who aim to mitigate the inherent challenges of future maritime trauma care in the age of Distributed Maritime Operations. This paper lays the framework of the Navy deployed medical system to enable research in maritime en-route care, and prompt inclusion of identified solutions into common use in the US Navy.

OSMANLI İMPARATORLUĞU’NUN BİRİNCİ DÜNYA SAVAŞI’NA GİRİŞİ VE İNGİLİZ BAHRİYE MİSYONU

After the proclamation of the Constitutional Monarchy in 1908, Admiral Arthur Henry Limpus was the last British adviser appointed as the naval adviser and the commander of the navy to the Ottoman Ministry of Marine. This study examines his efforts to establish a new naval base in the Gulf of Izmit and the end of his service period in the Ottoman Government after the outbreak of World War I. As the Imperial Naval Arsenal’s condition was far from meeting the repair and maintenance needs of both the naval warships and of the Reşadiye and Sultan Osman-ı Evvel dreadnoughts under construction in Britain, important steps were taken to realize a project for the establishment of a new naval base in the Gulf of Izmit with the cooperation of Armstrong-Vickers group and the Ministry of Marine. During the process that started with the confiscation of the Reşadiye and Sultan Osman-ı Evvel dreadnoughts by the British Government in July 1914 and the purchase of the German battlecruisers Goeben and Breslau by the Ottoman Government in August 1914, the British naval mission led by Admiral Limpus played an active role in the British Government's diplomatic campaign for the preservation of Ottoman neutrality. Based on Admiral Limpus’ private documents kept in the Caird Archive of the British National Maritime Museum the paper examines these developments.

Acoustic Radiation Characteristics from Shell Structure for Different Depth State

As a naval warship, submarine is a typical complex combined system. The excitation source of its vibration has the characteristics of large amplitude and wide frequency spectrum, and the prediction of vibro-acoustic radiation needs to be carried out in a wide frequency band. How to accurately predict the vibro-acoustic radiation of submarines in the whole frequency band has become a problem of practical significance. Elastic cylindrical shell is the typical structure of underwater vehicle. Studying acoustic radiation characteristics from shell structure for different depth state has a certain significance for studying submarine acoustic stealth characteristics. As an important acoustic performance metrics, the radiation sound power of underwater structure is significant for researching vibration and sound radiation characteristics. In this article, based on the FEM and BEM method, by using ANSYS and SYSNOISE software shell structure for different depth state is modeled and its vibration and radiation characteristics are researched. Numerical calculation shows that with immersed depth increasing, the vibration response and sound radiation power from shell structure gradually tend to the ones from under free field.

Сравнительный анализ сопротивления и мореходных качеств водоизмещающих однокорпусных кораблей при изменении носовой оконечности с традиционной на инвертированную

The paper primarily includes comparative performance analyses (i.e. changes/improvements in Resistance & Seakeeping characteristics) of a warship monohull (with a conventional bow), operating in displacement mode, when modified to various inverted bow forms. The work presented in the paper has been inspired by various research works already published worldwide and available literature regarding the same. For the research problem, a naval warship hull with conventional bow was taken as the benchmark and was suitably modified to a number of different hull form variants with inverted bow forms (i.e. Axe bow, Uistein X-bow, Sword bow and typical Inverted Bow forms), preserving sufficient characteristics for a meaningful comparison, yet making enough changes in various hull form parameters to obtain sufficient variations in hydrodynamic characteristics. Based on the analyses, it was possible to undertake multistage screening of the hull variants, as well as to obtain a considerable overview which enabled to make definitive comments regarding the research questions formulated.

Selective Engagement of US Naval Power in Maritime Conflicts: The Guardian of Freedom of Navigation

Since the Second World War, the United States has deterred conflictual behaviors over maritime claims that can impede the freedom of navigation, because it is essential for maintaining its leading position in the global system. Basically, many US naval warships operating in the sea clearly shows the US intention to maintain status quo and to prevent the occurrence of any types of disruptions in disputed maritime areas. However, it does not necessarily mean that the pacifying effect of US naval power is homogeneous to all maritime claims. When considering the vast area of the sea and the limited number of US naval warships, it is impossible to deploy an equal number of naval warships to all maritime areas. Therefore, the influence of US naval power in maintaining order in the sea is conditional based on the characteristic of maritime claims which can determine the US priority to use its naval power. This research finds that when maritime claims are related to the freedom of navigation, the pacifying effect of US naval power to maintain stability in the sea is increased.

Self-reported sleep and sleep deficiency: Results from a large initiative of sailors attached to U.S. Navy warships.

SummaryChronic insufficient sleep is known to lead to a broad range of negative consequences (e.g. poor health and cognitive performance). While insufficient sleep and associated fatigue are present in many diverse populations, it is of special concern in high‐risk military environments, where a mishap can result in catastrophic outcomes. Although many studies have been conducted to characterise sleep in general military populations, relatively few have been conducted using a large representative sample of sailors assigned to United States Naval warships. The present cross‐sectional study characterises self‐reported sleep parameters in sailors (N = 11,738) and explores the role of possible contributors to insufficient sleep. The results indicate that sailors, across a variety of different subgroups, do not obtain the amount of sleep that they report requiring for feeling well‐rested. Of the many potential factors thwarting sleep, workload and an uncomfortable mattress are the most promising candidates to target for improvement.

The conceptual of re-design propulsion system and ship electricity management to reduce waste emission

Climate change is a serious threat to the environment and socioeconomic globally. Climate change is caused by natural processes and due to human activities that have resulted in long-term climate fluctuations and even globally over the past few decades, the climate has experienced a fairly rapid rise in average temperatures. Climate change is mainly caused due to ozone depletion which results in changes in greenhouse effect conditions. The International Maritime Organization (IMO) has adopted standards to reduce sulfur pollution from ships. The majority of naval warships today use conventional mechanical propulsion systems where the power from the main propulsion is transmitted to the propeller through gearboxes. The ships owned by the Navy almost all still use conventional thrust systems with diesel engine starters. With a conventional support system. The latest innovation in the support system that has been carried out, namely on the United States Navy warship TAKE-1 (the destroyer ship), whereby changing the support system from conventional to electricity with the concept of Integrated Fully Electric Propulsion (IFEP) can reduce fuel use by 10% to 25%. IFEP application if applied to ships of the Navy, will obtain a very large benefit in overcoming environmental problems namely reducing air pollution.

A Model for the Optimal Mission Allocation of Naval Warship Based on Absorbing Markov Chain Simulation

A Model for the Optimal Mission Allocation of Naval Warship Based on Absorbing Markov Chain Simulation

Development of Interlocking Signal Simulator for Verification of Naval Warship Engineering Control Logics

Development of Interlocking Signal Simulator for Verification of Naval Warship Engineering Control Logics

Numerical analysis of air entrainment and exit temperature of a real scale conical infrared suppression (IRS) device

A numerical analysis has been performed on a real-scale infrared suppression device to estimate the air entrainment and corresponding temperature drop of the exhaust gases flowing through it. The analysis of the IRS device is done for the exhaust of a gas turbine plant installed on a naval warship. The operational data used in the analysis has been taken from LM2500 series gas turbine from GE. The numerical method solves the three dimensional, incompressible Navier-Stokes equations, the mass continuity equation and the two-equation based eddy viscosity model for the turbulent k-epsilon equations along with the energy equation in the flow field. The effect of using different number of nozzles at the gas turbine exit on the air entrainment and the exit plume temperature has been discussed. The results show that the maximum air entrainment and minimum plume temperature can be achieved by using four to six numbers of nozzles. The air entrainment and the exit plume temperature are also affected by the pitch circle diameter of the nozzle placement. The maximum air entrainment and minimum exit temperature is achieved at a pitch circle diameter of 1.6 m. The air entrainment considerably increases with the nozzle-exit Reynolds number (Re). The higher Reynolds number also ensures the minimum plume temperature at the exit of IRS device. Air entrainment gradually reduces with the nozzle protrusion. The highest entrainment is observed when the nozzles are flush with the bottom plane of the IRS device. However, the nozzle protrusion does not affect the exit plume temperature significantly. The funnel overlap height adversely affects the performance of the IRS device i.e. the air entrainment continuously decreases with increasing funnel overlap height. Moreover, increasing funnel overlap also causes the exit plume temperature to rise considerably.

Ingress of Threshold Voltage-Triggered Hardware Trojan in the Modern FPGA Fabric–Detection Methodology and Mitigation

The ageing phenomenon of negative bias temperature instability (NBTI) continues to challenge the dynamic thermal management of modern FPGAs. Increased transistor density leads to thermal accumulation and propagates higher and non-uniform temperature variations across the FPGA. This aggravates the impact of NBTI on key PMOS transistor parameters such as threshold voltage and drain current. Where it ages the transistors, with a successive reduction in FPGA lifetime and reliability, it also challenges its security. The ingress of threshold voltage-triggered hardware Trojan, a stealthy and malicious electronic circuit, in the modern FPGA, is one such potential threat that could exploit NBTI and severely affect its performance. The development of an effective and efficient countermeasure against it is, therefore, highly critical. Accordingly, we present a comprehensive FPGA security scheme, comprising novel elements of hardware Trojan infection, detection, and mitigation, to protect FPGA applications against the hardware Trojan. Built around the threat model of a naval warship's integrated self-protection system (ISPS), we propose a threshold voltage-triggered hardware Trojan that operates in a threshold voltage region of 0.45V to 0.998V, consuming ultra-low power (10.5nW), and remaining stealthy with an area overhead as low as 1.5% for a 28 nm technology node. The hardware Trojan detection sub-scheme provides a unique lightweight threshold voltage-aware sensor with a detection sensitivity of 0.251mV/nA. With fixed and dynamic ring oscillator-based sensor segments, the precise measurement of frequency and delay variations in response to shifts in the threshold voltage of a PMOS transistor is also proposed. Finally, the FPGA security scheme is reinforced with an online transistor dynamic scaling (OTDS) to mitigate the impact of hardware Trojan through run-time tolerant circuitry capable of identifying critical gates with worst-case drain current degradation.

Influence of Traverse Speed in Self-Reacting FSW of AA6061-T6

Influence of Traverse Speed in Self-Reacting FSW of AA6061-T6