996 resultados para Military engineering
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An optical technique is proposed for obtaining multiple excitation spots. Phase-matched counter propagating extended depth-of-focus fields were superimposed along the optical axis for generating multiple localized excitation spots. Moreover, the filtering effect due to the optical mask increases the lateral resolution. Proposed technique introduces the concept of simultaneous multiplane excitation and improves three-dimensional resolution. (C) 2010 American Institute of Physics.
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Design creativity involves developing novel and useful solutions to design problems The research in this article is an attempt to understand how novelty of a design resulting from a design process is related to the kind of outcomes. described here as constructs, involved in the design process A model of causality, the SAPPhIRE model, is used as the basis of the analysis The analysis is based on previous research that shows that designing involves development and exploration of the seven basic constructs of the SAPPhIRE model that constitute the causal connection between the various levels of abstraction at which a design can be described The constructs am state change, action, parts. phenomenon. input. organs. and effect The following two questions are asked. Is there a relationship between novelty and the constructs? If them is a relationship, what is the degree of this relationship? A hypothesis is developed to answer the questions an increase in the number and variety of ideas explored while designing should enhance the variety of concept space. leading to an increase in the novelty of the concept space Eight existing observational studies of designing sessions are used to empirically validate the hypothesis Each designing session involves an individual designer. experienced or novice. solving a design problem by producing concepts and following a think-aloud protocol. The results indicate dependence of novelty of concept space on variety of concept space and dependence of variety of concept space on variety of idea space. thereby validating the hypothesis The Jesuits also reveal a strong correlation between novelty and the constructs, correlation value decreases as the abstraction level of the constructs reduces. signifying the importance of using constructs at higher abstraction levels for enhancing novelty
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In the recent time CFD tools have become increasingly useful in the engineering design studies especially in the area of aerospace vehicles. This is largely due to the advent of high speed computing platforms in addition to the development of new efficient algorithms. The algorithms based on kinetic schemes have been shown to be very robust and further meshless methods offer certain advantages over the other methods. Preliminary investigations of blood flow visualization through artery using CFD tool have shown encouraging results which further needs to be verified and validated.
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This paper develops a model for military conflicts where the defending forces have to determine an optimal partitioning of available resources to counter attacks from an adversary from n different fronts. The problem of optimally partitioning the defending forces against the attacking forces is addressed. The Lanchester square law model is used to develop the dynamical equations governing the variation in force strength. Two different allocation schemes-Time-ZeroAllocation (TZA) and Continuous Constant Allocation (CCA) are considered and the optimal solutions for both are obtained analytically. These results generalize other results available in the literature. Numerical examples are given to support the analytical results.
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In this paper, the work that has been done in several laboratories and academic institutions in India in the area of wind engineering in the past 20–30 years has been reviewed. Studies on extreme and mean hourly winds, philosophies adopted in model studies in wind tunnels and some of the important results that have been obtained are described. Suggestions for future studies are indicated.
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Thirteen host guest compounds of 3,5-dihydroxybenzoic acid (DHBA) have been structurally characterized. Water molecules occupy the peripheries of a hexagonal void, created with DHBA molecules, and act as ``hooks'' to connect the guest molecules with the host-framework via hydrogen bonding. The ``water hook'' is an OH group acting as a donor. Consequently, the guest molecules were chosen so that they contain good hydrogen bond acceptor functionalities. A number of multicomponent hydrates were isolated with stoichiometries (DHBA)(x)(H2O). (guest),. Of these, compounds with the following as guests were obtained as crystals that were good enough for single crystal work: ethyl acetate (EtOAc), diethyl oxalate, dimethyl oxalate, di(n-propyl) oxalate, diethyl malonate, diethyl succinate, chloroacetonitrile, N,N-dimethyl formamide (DMF), acetone, dimethyl sulfoxide (DMSO), 1-propanol, and 2-butanol. From 2-butanol, a hemihydrate, (DHBA)(2)(H2O), was also obtained concomitantly. Further to guest stabilization, water acts as a good mediator of effective crystal packing and also determines the topology of the host framework. En the present series of compounds, the role of water is wide ranging, and it is not easy to classify it specifically as a host or as a guest.
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Enzymes offer many advantages in industrial processes, such as high specificity, mild treatment conditions and low energy requirements. Therefore, the industry has exploited them in many sectors including food processing. Enzymes can modify food properties by acting on small molecules or on polymers such as carbohydrates or proteins. Crosslinking enzymes such as tyrosinases and sulfhydryl oxidases catalyse the formation of novel covalent bonds between specific residues in proteins and/or peptides, thus forming or modifying the protein network of food. In this study, novel secreted fungal proteins with sequence features typical of tyrosinases and sulfhydryl oxidases were iden-tified through a genome mining study. Representatives of both of these enzyme families were selected for heterologous produc-tion in the filamentous fungus Trichoderma reesei and biochemical characterisation. Firstly, a novel family of putative tyrosinases carrying a shorter sequence than the previously characterised tyrosinases was discovered. These proteins lacked the whole linker and C-terminal domain that possibly play a role in cofactor incorporation, folding or protein activity. One of these proteins, AoCO4 from Aspergillus oryzae, was produced in T. reesei with a production level of about 1.5 g/l. The enzyme AoCO4 was correctly folded and bound the copper cofactors with a type-3 copper centre. However, the enzyme had only a low level of activity with the phenolic substrates tested. Highest activity was obtained with 4-tert-butylcatechol. Since tyrosine was not a substrate for AoCO4, the enzyme was classified as catechol oxidase. Secondly, the genome analysis for secreted proteins with sequence features typical of flavin-dependent sulfhydryl oxidases pinpointed two previously uncharacterised proteins AoSOX1 and AoSOX2 from A. oryzae. These two novel sulfhydryl oxidases were produced in T. reesei with production levels of 70 and 180 mg/l, respectively, in shake flask cultivations. AoSOX1 and AoSOX2 were FAD-dependent enzymes with a dimeric tertiary structure and they both showed activity on small sulfhydryl compounds such as glutathione and dithiothreitol, and were drastically inhibited by zinc sulphate. AoSOX2 showed good stabil-ity to thermal and chemical denaturation, being superior to AoSOX1 in this respect. Thirdly, the suitability of AoSOX1 as a possible baking improver was elucidated. The effect of AoSOX1, alone and in combi-nation with the widely used improver ascorbic acid was tested on yeasted wheat dough, both fresh and frozen, and on fresh water-flour dough. In all cases, AoSOX1 had no effect on the fermentation properties of fresh yeasted dough. AoSOX1 nega-tively affected the fermentation properties of frozen doughs and accelerated the damaging effects of the frozen storage, i.e. giving a softer dough with poorer gas retention abilities than the control. In combination with ascorbic acid, AoSOX1 gave harder doughs. In accordance, rheological studies in yeast-free dough showed that the presence of only AoSOX1 resulted in weaker and more extensible dough whereas a dough with opposite properties was obtained if ascorbic acid was also used. Doughs containing ascorbic acid and increasing amounts of AoSOX1 were harder in a dose-dependent manner. Sulfhydryl oxidase AoSOX1 had an enhancing effect on the dough hardening mechanism of ascorbic acid. This was ascribed mainly to the produc-tion of hydrogen peroxide in the SOX reaction which is able to convert the ascorbic acid to the actual improver dehydroascorbic acid. In addition, AoSOX1 could possibly oxidise the free glutathione in the dough and thus prevent the loss of dough strength caused by the spontaneous reduction of the disulfide bonds constituting the dough protein network. Sulfhydryl oxidase AoSOX1 is therefore able to enhance the action of ascorbic acid in wheat dough and could potentially be applied in wheat dough baking.
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States regularly deploy elements of their armed forces abroad. When that happens, the military personnel concerned largely remain governed by the penal law of the State that they serve. This extraterritorial extension of national criminal law, which has been treated as axiomatic in domestic law and ignored by international law scholarship, is the subject of this dissertation. The first part of the study considers the ambit of national criminal law without any special regard to the armed forces. It explores the historical development of the currently prevailing system of territorial law and looks at the ambit that national legal systems claim today. Turning then to international law, the study debunks the oddly persistent belief that States enjoy a freedom to extend their laws to extraterritorial conduct as they please, and that they are in this respect constrained only by some specific prohibitions in international law. Six arguments historical, empirical, ideological, functional, doctrinal and systemic are advanced to support a contrary view: that States are prohibited from extending the reach of their legal systems abroad, unless they can rely on a permissive principle of international law for doing so. The second part of the study deals specifically with State jurisdiction in a military context, that is to say, as applied to military personnel in the strict sense (service members) and various civilians serving with or accompanying the forces (associated civilians). While the status of armed forces on foreign soil has transformed from one encapsulated in the customary concept of extraterritoriality to a modern regulation of immunities granted by treaties, elements of armed forces located abroad usually do enjoy some degree of insulation from the legal system of the host State. As a corollary, they should generally remain covered by the law of their own State. The extent of this extraterritorial extension of national law is revealed in a comparative review of national legislation, paying particular attention to recent legal reforms in the United States and the United Kingdom two states that have sought to extend the scope of their national law to cover the conduct of military contractor personnel. The principal argument of the dissertation is that applying national criminal law to service members and associated civilians abroad is distinct from other extraterritorial claims of jurisdiction (in particular, the nationality principle or the protective principle of jurisdiction). The service jurisdiction over the armed forces has a distinct aim: ensuring the coherence and indivisibility of the forces and maintaining discipline. Furthermore, the exercise of service jurisdiction seeks to reduce the chances of the State itself becoming internationally liable for the conduct of its service members and associated civilians. Critically, the legal system of the troop-deploying State, by extending its reach abroad, seeks to avoid accountability gaps that might result from immunities from host State law.
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Crystal structures of organic and metal-organic compounds have been determined in enormous numbers over the past century, and at the time of writing this review, the Cambridge Structural Database has just crossed the half million mark. The possibility of designing a particular crystal packing is, however, of more recent origin and the subject of crystal engineering has addressed this possibility, more or less systematically, during the past 30 years. Crystal engineering demands a detailed and thorough knowledge of intermolecular interactions, which act as the supramolecular glue that binds molecules into crystals. It also requires systematic strategies for the design of a crystal, the architectural blueprint as it were. Finally, this enterprise needs to be geared towards a useful property in that the crystal that is being designed is a functional one. All these features of the subject are directly or indirectly connected with the fact that there is a very large database of known crystal structures that is available to the crystal engineer. This review attempts to briefly survey the current scenario in this expanding subject.
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Studies in crystal engineering. Photochemical and crystallographic investigations of bromocoumarins and (±)-7-(p-bromobenzylidene)piperitone
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The present study aims to assess whether the smectite-rich Cochin and Mangalore clays, which were deposited in a marine medium and subsequently uplifted, exhibit consistency limits response typical of expanding lattice or nonexpanding (fixed) lattice-type clays on artificially changing the chemical environment. The chemical and engineering behaviors of Cochin and Mangalore marine clays are also compared with those of the smectite-rich Ariake Bay marine clay from Japan. Although Cochin, Mangalore, and Ariake clays contain comparable amounts of smectite (32-45%), Ariake clay exhibits lower consistency limits and much higher ranges of liquidity indices than the Indian marine clays. The lower consistency limits of the Ariake clay are attributed to the absence of well-developed, long-range, interparticle forces associated with the clay. Also, Ariake clay exhibits a significantly large (48-714 times) decrease in undrained strength on remolding in comparison to Cochin and Mangalore clays (sensitivity ranges between 1 and 4). A preponderance of long-range, interparticle forces reflected in the high consistency limits of Cochin and Mangalore clays (wL range from 75 to 180%) combined with low natural water contents yield low liquidity indices (typically <1) and high, remolded, undrained strengths and are considered to be responsible for the low sensitivity of the Indian marine clays.
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The dissertation examines aspects of asymmetrical warfare in the war-making of the German military entrepreneur Ernst von Mansfeld during his involvement in the Thirty Years War. Due to the nature of the inquiry, which combines history with military-political theory, the methodological approach of the dissertation is interdisciplinary. The theoretical framework used is that of asymmetrical warfare. The primary sources used in the dissertation are mostly political pamphlets and newsletters. Other sources include letters, documents, and contemporaneous chronicles. The secondary sources are divided into two categories, literature on the history of the Thirty Years War and textbooks covering the theory of asymmetrical warfare. The first category includes biographical works on Ernst von Mansfeld, as well as general histories of the Thirty Years War and seventeenth-century warfare. The second category combines military theory and political science. The structure of the dissertation consists of eight lead chapters, including an introduction and conclusion. The introduction covers the theoretical approach and aims of the dissertation, and provides a brief overlook of the sources and previous research on Ernst von Mansfeld and asymmetrical warfare in the Thirty Years War. The second chapter covers aspects of Mansfeld s asymmetrical warfare from the perspective of operational art. The third chapter investigates the illegal and immoral aspects of Mansfeld s war-making. The fourth chapter compares the differing methods by which Mansfeld and his enemies raised and financed their armies. The fifth chapter investigates Mansfeld s involvement in indirect warfare. The sixth chapter presents Mansfeld as an object and an agent of image and information war. The seventh chapter looks into the counter-reactions, which Mansfeld s asymmetrical warfare provoked from his enemies. The eighth chapter offers a conclusion of the findings. The dissertation argues that asymmetrical warfare presented itself in all the aforementioned areas of Mansfeld s conduct during the Thirty Years War. The operational asymmetry arose from the freedom of movement that Mansfeld enjoyed, while his enemies were constrained by the limits of positional warfare. As a non-state operator Mansfeld was also free to flout the rules of seventeenth-century warfare, which his enemies could not do with equal ease. The raising and financing of military forces was another source of asymmetry, because the nature of early seventeenth-century warfare favoured private military entrepreneurs rather than embryonic fiscal-military states. The dissertation also argues that other powers fought their own asymmetrical and indirect wars against the Habsburgs through Mansfeld s agency. Image and information were asymmetrical weapons, which were both aimed against Mansfeld and utilized by him. Finally, Mansfeld s asymmetrical threat forced the Habsburgs to adapt to his methods, which ultimately lead to the formation of a subcontracted Imperial Army under the management and leadership of Albrecht von Wallenstein. Therefore Mansfeld s asymmetrical warfare ultimately paved way for the kind of state-monopolized, organised, and symmetrical warfare that has prevailed from 1648 onwards. The conclusion is that Mansfeld s conduct in the Thirty Years War matched the criteria for asymmetrical warfare. While traditional historiography treated Mansfeld as an anomaly in the age of European state formation, his asymmetrical warfare has begun to bear resemblance to the contemporary conflicts, where nation states no longer hold the monopoly of violence.