Defence against an amphibious assault is an extremely difficult endeavour as is evident by the long line of successful amphibious assaults undertaken throughout history. Field fortifications has to a large extent been present in defences, yet little research has been done on the effects of field fortifications in preventing successful landing operations. Therefore, this thesis examines the specific role of field fortifications in defence against amphibious assaults. The purpose is to combine theories about amphibious operations with concepts of field fortifications to add depth to existing theories as two historical examples are examined.  Results show that the existing theories’ notions, especially regarding the devastating effects of indirect fire and pre-bombardment, are not true for the two cases of study. It is furthermore shown that avoiding terrain where the enemy’s defence is focused was of little consequence for whether the assault was successful or not. Of greater importance was the power imbalance of attacker versus defender. Lastly, it is argued that the development of advanced weaponry plausibly levels out the power imbalance as effects of pre-bombardment is more likely to be successful.

Approved for public release; distribution in unlimited. / In Littoral Warfare (LW), naval operations face a whole new range of missions and types of threats. In such situations, Electronic Warfare (EW) systems are extremely important, yet constantly challenged to perform faster and more accurate detection and recognition of potential threats. However, meteorological and oceanographic (METOC) factors can severely modify the effectiveness of EW systems, particularly against low detectable targets in warm waters. Therefore, this thesis analyzes the effects of tropical littoral environments in the expected performance of generic RF and IR systems when used under these scenarios. It analyzes the outputs of propagation models included in the software suites AREPS and TAWS when using actual data from different sources in the Yucatan Channel. The results of this study demonstrated how radically the environmental conditions can change, clearly modifying the efficiency of surveillance and detection systems in shipborne platforms. Further, several issues related to the need of valuable data and additional research are addressed, while providing useful insights to operational commanders and decision makers for the use of EW systems and available Tactical Decision Aids (TDAs) at the typical scenarios of Littoral Warfare in tropical waters. / Lieutenant Commander, Mexican Navy

The goal of this work was to evaluate an electronic warfare system from a human factors engineering perspective. The evaluation began by looking at the top-level system requirements and included a functional analysis of critical components of the man-machine interface. Once a critical operator task was identified, two separate trade-off studies provided objective data for redesign recommendations. The first section of this work defines the operational requirements and maintenance concept for an electronic warfare system. This is the first step in defining the human interface requirements for the system. The second section provides a brief history of the U.S. Navy's AN/SLQ-32(V) Electronic Warfare System. Although recognized as an integral part of the U.S. Navy's defense against low-flying anti-ship missiles, several incidents indicate a need for system improvement. The next section of this work defines the AN/SLQ-32(V). The definition starts from a macro-level and, then, discusses the system to the level necessary to understand the system. The goal was to conduct and document a task analysis of the interface between the operator and the AN/SLQ-32(V). This task analysis was used as a tool to compare system redesign options. The final section of the work involved the acquisition of information from naval operators and the assessment of existing system design features from actual and simulated Display Control Consoles (DCC). The critique of these data considered operator task requirements in actual and simulated electronic warfare scenarios. This included the time required to detect, analyze, and act-upon radar intercepts in anti-ship missile defense. From this evaluation, recommendations were developed and justified for DCC system design changes. / Master of Science

Approved for public release, distribution is unlimited / This thesis will address the planned configuration of Lockheed Martin's Flight Zero, Module Spiral Alpha Littoral Combat Ship (LCS) and the ongoing development of the SPARTAN SCOUT, one of the Navy's Unmanned Surface Vessels (USV). Technology currently available as well as developmental technologies will be recommended for implementation in order to make the LCS and SCOUT assets to Information Operations (IO) objectives. Specific technology will include Outboard, TARBS, HPM, Loudspeakers, LRAD and Air Magnet. This thesis will include an evaluation of the current policy for authorizing Information Operations missions, specifically in the areas of Psychological Operations (PSYOP) and Electronic Warfare (EW). / Lieutenant, United States Navy

Approved for public release; distribution in unlimited. / This is a study of abnormal refractive layer occurrence over the Amazon region and possible effects on radar and ESM systems, ground or airborne based. Climatologic data from three stations in that region are analyzed using computations from the Global Tropospheric Experiment (GTE), soundings and satellite imagery. The GTE data provide monthly occurrences and seasonality of atmospheric ducts and superrefractive layers. Further, individual soundings from the March-June 2003 period and the Advanced Refractive Effects Prediction Systems (AREPS) 2.1 software are used in a case study that analyzed these layers and, in addition, subrefractive and multiple layers. Selected soundings were used in simulations to explain the effects of different types of abnormal layers on the electromagnetic propagation. Although abnormal layers did not affect ground systems, airborne ones were. For radar, a region with low or no detection is created when an abnormal layer refracts the electromagnetic energy upwards or downwards. Some combinations of multiple layers may cause effects even stronger. It is concluded that knowledge of the abnormal layers occurrence is important for operations in the Amazon region. Further, airborne radar platforms should measure local refractive conditions, if possible. A comprehensive study in time and space is recommended to provide forecasting. / Lieutenant Colonel, Brazilian Air Force

Thesis (M.S. in Joint Campaign Planning and Strategy)--Joint Forces Staff College, Joint Advanced Warfighting School, 2007. / "5 April 2007." AD-A468 869. Includes bibliographical references. Also available via the World Wide Web.

Force deployment and optimal resource allocation has been an area of considerable research interest in conventional warfare. In the modern scenario, with significant advances in technology related to communication and computation, sophisticated decision-making in these situations has become feasible. This has generated renewed interest in formulating decision-making problems in these areas and seeking optimal solutions to them. This thesis addresses one such problem in which the defending forces need to optimally Partition their resources between several attacking forces of differing strengths. The basic model considered for resource allocation is Lanchester attrition models. Lanchester models are deterministic differential equations that model attrition to forces in convict. In this thesis we address a resource allocation problem where the resource allocation is done using different approaches. First, we developed a (2,1) model using the Lanchester square law model for attrition. For this model we assumed that the attacking force consists of two types of forces and the defending force consists of only one type of force. The objective is to optimally partition the defending force against the two attacking forces so as to maximize the surviving defending force strength and to minimize the attacking force strength. The objective function considered in this thesis is the weighted sum of the surviving defending force strength and the destroyed attacking force strength. We considered a resource allocation problem in which allocation of resources are done using four different approaches. The simplest is the case when allocation is done initially and no further action is taken Iv Abstract v (Time Zero Allocation (TZA)). For the TZA allocation scheme, when any of attacking forces gets destroyed, the corresponding defending force which was engaging that attacking force will stop interacting further. This situation rarely happens in reality. Hence to make this scenario more realistic, we considered another allocation scheme in which allocation is followed by redistribution of resources depending on certain decisive events (Time Zero Allocation with Redistribution (TZAR)). In TZA and TZAR schemes, the allocation of defending force is done only at the initial time. Deviating from this assumption, we considered another allocation scheme in which a constant allocation ratio is used continuously over time till the end of the convict (Continuous Constant Allocation (CCA). To account for the redistribution of resources we extended this allocation scheme to the case in which continuous constant allocation is followed by redistribution of the resources (Continuous Constant Allocation with Redistribution (CCAR)). In each of these formulations we define the conditions for an optimal resource partitioning and allocation. We were able to obtain analytical expression for resource partitioning in almost all of these cases. Next, in order to consider situations in which area fire is required, we developed a (2,1) model using Lanchester linear law model for attrition. Here we considered a resource allocation problem in which the resource allocation is done using ideas similar to the square law case. In the Linear law, the resources will get destroyed completely only at infinite time, hence a situation for redistribution of resources does not arise for this law. We considered Time Zero Allocation and Continuous Constant Allocation schemes for this law. We obtained analytical results for the TZA scheme. For the CCA scheme, closed form solutions are difficult to obtain but numerical solutions were obtained. The above schemes were extended to an (n, 1) model for resource allocation using Lanchester square and linear laws. Here the defending forces have to determine an optimal partitioning of available resources to counter attacks from an adversary from n different fronts. For the square law model, we considered both TZA and CCA schemes for resource allocation. As the number of force types increases, the equations becomes much more complicated and the analytical solutions are difficult to obtain. We were able to obtain analytical solutions for some of the situations that occurs during the conflict. For the linear law, we considered only the TZA scheme since, even for the simpler (2,1) model, the analytical solutions are difficult to obtain for the CCA scheme. The resource allocation strategies developed in this thesis contribute to the growing research in the field of conflicts. The thesis concludes with a discussion on some future Extensions of this work.

A Primary objective of the present research is the development of robust CAE (Computer-Aided Engineering)-based approaches for designing armour plates subjected to ballistic impact by small-calibre hardened peojectiles with or without a protective sheath. Amongst the challenges in simulation is the capturing of target plate material behaviour at high strain rates with possibilities of adiabatic heating. A comprehensive numerical study carried out has resulted in the identification of simulation guidelines using a commercially available explicit finite element anlaysis solver (viz. LS_DYNA). The interferences thus drawn in terms of modeling approach 9I.e. shell, solid or axisymmetric or a mixed representation). Mesh density and element type, contact condition, and constitutive model 9I.e. discrete strain-rate based, Cowper-Symonds, or Johnson-Cook) with failure criteria are verifiable and greatly beneficial for armour plate design. Confidence in the suggested procedures has been obtained through extensive correlation of numerical results with experimental residual velocities and ballistic limits as well as projectile and target plate failure modes. A wide range of impact velocities has been considered (from a low velocity of about 5m/s to an ordnance range velocity of 800+ m/s). Target plates made of variants of mild steel and aluminium alloys have been studied. The simulation approaches have been applied to single-layered as well as multi-layered target plates. Although a majority of the comparisons has been made against published test results, a new ballistic impact testing facility has been set up in course of the current research and excellent correlation of numerically predicted residual velocities and failure modes has been obtained against the tests carried out for aluminium plate using the latter facility. A unique feature of the current experimental effort is the capturing of the complete trajectory of projectile beginning with oblique impact through subsequent perforation/ricochet. Furthermore, projectiles of various nose-shapes such as ogival, conical, hemispherical and blunt have been employed. The power of simulation has been demonstrated with the help of a number of parametric studies with variables such as plate thickness and material properties, as well as projectile mass and diameter, and obtaining physically consistent results. Additionally, existing semi empirical models for residual velocity and ballistic limit prediction have been reviewed, and new user-friendly models have been proposed based on energy conservation and predominant shear plugging failure mode of target plate. Finally, the goal of applying the present research work as a design tool can be well-served by packaging the knowledge gathered here in the form of a user-friendly guide with a graphical user interface(GUI). To this end, an application using MS windows VC++ utilities has been created with the functionalities of: (a) viewing reference LS-DYNA input data files for selecting typical problems of impact on steel and aluminium plates; (b) computing complete lists of strain rate-based material quantities required in LS-DYNA material models like discrete strain rate-based, Cowper-Symonds and Johnson-Cook by specifying the minimum number of easily available quasi-static properties (such as elastic modulus, yield and ultimate strengths, etc.), and (c) estimating residual velocities using the semi-empirical relations for steel and aluminium plates derived in the current work.

Thesis (M.S. in Systems Engineering (Electronic Warfare))--Naval Postgraduate School, September 1990. / Thesis Advisor(s): Davidson, Kenneth L. ; Powell, James R. "September 1990." Description based on title screen as viewed on December 29, 2009. DTIC Descriptor(s): Frequency, Electronic Warfare, Aircraft, Airborne, Electronic Equipment, Microwave Equipment, Radar, Profiles, Ducts, Meteorology, Communication And Radio Systems, Refraction, Arabian Sea, Refractometers, Military Operations. DTIC Identifier(s): Radar interference, meteorological phenomena, theses. Author(s) subject terms: Refractivity, Arabian Sea refractive conditions, ESM airborne radar, airborne microwave refractometer (AMR), IREPS, EREPS. Includes bibliographical references (p. 96-97). Also available in print.

Thesis (MComm)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: Defence forces around the world are experiencing a period of dynamic change with new force structures being combined with new technologies in an effort to enhance effectiveness. Present day resources and technology available to the modern society, have facilitated the evolution of warfare as a technologically advanced enterprise, with the decided emphasis on the digitisation of the battlefield. With rapid development in the field of battlefield digitisation there is an increasing need to address the important issues and challenges facing the military. In order to meet strategic defence guidelines, it is necessary to integrate the capabilities of defence forces with modern technology. In this regard the South African Defence Force is striving towards the digitisation of the battlefield. This digitisation can potentially satisfy the many requirements set for the Defence Force, in a more timely and cost-effective manner than traditional methods of functioning and training would be able to achieve. Effective situational awareness and command and control structures are essential for any military operation, especially with increasingly complex military demands. Key areas of importance are the collection, dissemination and management of information, which if executed skilfully, will result in forces capable of operating more effectively and with greater flexibility. Decision makers on the battlefield continually suffer from information overload due to the extremely rapid inflow of information. This is likely to worsen with the continued introduction of new information technologies. The technology level of any defence force should therefore be appropriate, driven by usefulness and cost-effectiveness. The digitised battlefield allows for the execution of near realistic military exercises, while conserving material and reducing the detrimental impact on environment and personnel, as is the case with traditional exercises. A key issue of focus is the usability and integration of related technologies within the digital battlefield. Promoting optimal usability through continuous and comprehensive user-based evaluation is crucial and will result in increased human performance through interaction with technology. Optimal usability must be engineered into any product (defined as something produced by means of either human or mechanical work) from the inception of the product's life cycle. Within today's technology orientated society, the digitisation of the battlefield and the usability thereof have become increasingly important issues. Most research has investigated the concepts of battlefield digitisation and usability in isolation, and little co-ordinated effort has been made to integrate digitisation and usability, even though the relation is important and necessary. A study of this nature has not hitherto been conducted within the South African military context. The purpose of this study is to provide a theoretical background of the issues of military digitisation and usability, in order to determine the significance of this relation. This research aims specifically to promote the viewpoint that usability is central to military digitisation, as well as to emphasise the importance of user-centred approaches to system development and utilization. The result will be enhanced human performance and satisfaction when interacting with digital battlefield applications. The theoretical perspective is provided by way of a literature review of the relevant military and usability concepts. Military functioning is discussed, highlighting the importance of situational awareness and effective command and control capabilities. The digitisation in the military is examined with specific reference to Virtual Reality and simulation. An overview of usability (within a human-computer interaction and user-centred design context) and usability evaluation methods are provided. This research was conducted during a military exercise conducted by the South African National Defence Force. A usability inquiry approach was followed with questionnaires distributed to participants involved with the Command and Control Digital Battlefield System. Information was obtained concerning participants' characteristics, likes, dislikes, needs, and understanding of the digital battlefield system. The analyses of the information consisted of descriptive statistics as the research aimed to illustrate the attitudes concerning usability and the digital battlefield. The results provide an understanding of the perceptions of the users regarding the digital battlefield system and its usability. Conclusions are drawn from results obtained and recommendations are made for future research. / AFRIKAANSE OPSOMMING: Moderne weermagte deur die wereld ervaar tans 'n peri ode van dinamiese verandering met nuwe magstrukture wat met nuwe tegnologiee gekombineer word ter bevordering van doeltreffendheid. Die hedendaagse hulpbronne en tegnologie tot die moderne samelewing se beskikking, het meegebring dat oorlogvoering ontwikkel het in 'n tegnologies gevorderde aksie met die klem op gevegsterrein-digitalisering. Die betreding van 'n era van tegnologies gevorderde oorlogvoering met die gepaardgaande snelle ontwikkelings in die veld van gevegsterrein digitalisering, het 'n toenemend groeiende behoefte laat ontstaan vir die indringende aanspreking van belangrike strydvrae en uitdagings wat 'n moderne weermag in die gesig staar.Tiit is noodsaaklik dat die vermoens van weermagte geintegreer word met moderne tegnologie ten einde aan strategiese verdedigingsvereistes te kan voldoen. Die Suid-Afrikaanse Nasionale Weermag het digitalisering van die gevegsterrein ten doel. Sodanige digitalisering kan potensieel die talle vereistes gestel aan 'n weermag op 'n meer tydige en koste-effektiewe wyse bevredig as wat met tradisionele metodes van funksionering en opleiding gedoen kan word. Effektiewe situasionele bewustheid en bevel en beheer strukture, is onontbeerlik in enige militere operasie, veral in die lig van toenemende komplekse eise gestel aan die moderne weermag. Sleutelareas van belang is die insameling, disseminasie en bestuur van inligting, wat as dit met die nodige insig en kundigheid uitgevoer word, aanleiding sal gee tot die verhoogde doeltreffendheid en buigsaamheid van 'n weermag. Die tegnologiese vlak van enige weermag behoort dus toepaslik en bruikbaar te wees, sowel as koste-effektief gedrewe. Die gedigitaliseerde gevegsterrein maak vcorsiening vir die uitvoering van bykans-realistiese militere oefeninge met behoud van material en grootskaalse uitskakeling van die negatiewe invloede op die omgewing en personeel, meer so as wat andersins die geval sou wees met tradisionele oefeninge. 'n Sleutel-aspek is die bruikbaarheid en integrasie van verwante tegnologiee in 'n gedigitaliseerde gevegsterrein. Die bevordering van optimale bruikbaarheid deur aaneenlopende en omvattende gebruikersbaseerde evaluasies, is deurslaggewend en sal lei tot verhoogde gebruiker prestasie betreffende interaksie met tegnologie. Optimale bruikbaarheid moet reeds vanaf die aanvang van 'n produk se lewenssiklus, bewerkstellig word. In die hedendaagse tegnologie-gebaseerde moderne same lewing, het digitalisering van die gevegsterrein en die bruikbaarheid daarvan, toenemend belangrik geword. In die meeste navorsmg word gevegsterrein digitalisering, asook bruikbaarheid, afsonderlik ondersoek, onafgesien van die belangrike verwantskap daartussen, en slegs geringe gekoordineerde pogings is van stapel gestuur om digitalisering en bruikbaarheid te integreer. In die Suid-Afrikaanse rnilitere konteks is so 'n studie nog nie uitgevoer nie en derhalwe het hierdie studie ten doel om 'n teoretiese agtergrond te voorsien van militere digitalisering- en bruikbaarheidskwessies, asook die vasstelling van die verwantskap daartussen. Hierdie navorsing het spesifiek ten doel om die standpunt te bevorder dat bruikbaarheid sentraal staan tot militere digitalisering sowel as om die gebruiker-gebaseerde benadering tot sisteem ontwikkeling en benutbaarheid, te bevorder. Die resultaat sal verhoogde gebruikerprestasie en tevredenheid wees wanneer interaksie met gedigitaliseerde gevegsterrein toepassings plaasvind. Die teoretiese perspektief word voorsien deur 'n literatuur-oorsig van die relevante rnilitere- en bruikbaarheidskonsepte. Militere funksionering word bespreek met beklemtoning van die belang van situasionele bewustheid en doeltreffende bevel en beheer vermoens, Militere digitalisering word ondersoek met spesifieke verwysing na virtuele realiteit en simulasie. 'n Oorsig van bruikbaarheid (binne die konteks van mens-rekenaar interaksie en gebruikersgeorienteerde ontwerp) sowel as bruikbaarheidsevaluasie-metodes word voorsien. Hierdie navorsing is uitgevoer tydens 'n militere oefening van die Suid-Afrikaanse Nasionale Weermag. 'n Bruikbaarheidsondersoek-benadering is gevolg deur vraelyste uit te deel aan die deelnemers wat betrokke was by die gedigitaliseerde bevel en beheer stelsel. Informasie is ingewin betreffende die deelnemers se kenmerke, persepsies, voorkeure, afkeure, behoeftes en begrip van die gedigitaliseerde gevegsterrein-stelsel. Die analise van die informasie het beskrywende statistieke behels omdat die navorsing ten doe I gehad het om ingesteldhede betreffende bruikbaarheid en die gedigitaliseerde gevegsterrein, uit te lig. Die resultate voorsien 'n begrip van die persepsies van die gebruikers rakende die gedigitaliseerde gevegsterrein, en die bruikbaarheid daarvan. Gevolgtrekkings word gemaak vanuit die resultate verkry en aanbevelings word voorsien vir verdere toekomstige navorsing.