This paper aims to present some aspects associated with the life prediction of structures with fatigue cracks growing from small natural discontinuities in aluminium alloy…
This paper aims to present some aspects associated with the life prediction of structures with fatigue cracks growing from small natural discontinuities in aluminium alloy (AA)7050‐T7451 for a surface condition that is present in F/A‐18 A/B aircraft critical structure.
Fatigue results are presented for thick section AA7050 plate coupons loaded with a representative fighter aircraft wing root bending moment loading spectrum. Detailed quantitative fractography (QF) was used to gain a deeper understanding of issues relevant to an improved fatigue life predictive capacity for this material by using the QF results to investigate the “effectiveness” of the fatigue initiating discontinuities.
Estimates of the “effectiveness” of the fatigue initiating discontinuities as quasi pre‐existing fatigue cracks (“equivalent pre‐crack size” (EPS) here) were made with the aid of a simple crack growth model. This model, based on experience, was found to be valid for the applied spectrum and stress levels used. These stress levels were chosen to represent those that may be found in highly stressed locations of fighter aircraft; and as such would usually lead to the limiting fatigue life of such a structure.
The method has been extended to other crack growth situations and is being used to build a database large enough to determine the best probability distribution of the “effectiveness” of the fatigue initiating discontinuities for not only the surface condition reported here but several other surface conditions typical of aircraft metallic structure.
The EPS of the discontinuities from which the cracks grew were used to investigate distributions that may be used in a risk‐based assessment using deterministic crack growth measurements from such discontinuities. Some of the problems that remain to be resolved in such an analysis, prior to its use in a risk‐based assessment are discussed.
This work improves the understanding of the interaction of small fatigue cracks generated by representative loading spectra with the small discontinuities from which they grow and shows that the fatigue process is remarkably consistent down to very small sizes.
Moldova is one of the smallest constituent Republics of the C.I.S., with a population of just 4.3 million inhabitants. In agrifood terms however, Moldova has traditionally…
Moldova is one of the smallest constituent Republics of the C.I.S., with a population of just 4.3 million inhabitants. In agrifood terms however, Moldova has traditionally been one of the key “food baskets” for the rest of the former Soviet Union. Nowhere is this more marked than in the production of wine, with Moldova still supplying 20% of the total wine production of the former Soviet Union. In Central and East European terms the Moldovan wine industry is substantial; producing annually as much wine as Hungary and “Czechoslovakia” combined. This paper provides an overview of the Moldovan wine industry, highlighting key production and structural difficulties facing it as it attempts to gain access to hard currency earning markets outside the former Soviet Union. In particular, the problems caused by the recent reversion to the traditional monopoly‐monopsony structure within the Moldovan wine marketing channel are analysed. Suggestions are made for true liberalisation of the Moldovan wine marketing system, based upon three elements:‐ (i) De‐nationalisation, and a move to new private structures of ownership of Moldovan wineries; (ii) Modernisation of vineyard practices and production methods, driven by private incentive. (iii) The establishment of effective networks of marketing and distribution, based upon private wineries pursuing real markets.
This is the second set of lecture notes from courses in public finance published in an archival volume in this series. Volume 19-C (2001) was entirely devoted to notes…
This is the second set of lecture notes from courses in public finance published in an archival volume in this series. Volume 19-C (2001) was entirely devoted to notes from lectures by E. R. A. Seligman at Columbia University. Two differences mark Seligman’s lectures and the lectures by Henry C. Simons at Chicago, as reported below. Seligman seems to have been lecturing primarily to students in tax administration, hence he presented very little economic theory; whereas Simons was lecturing to graduate students in economics, and presented relatively more theory. Seligman did not refrain from some passing of judgment but his lectures were largely descriptive and non-judgmental; whereas Simons has no hesitation in presenting his own normative approach on various issues. These issues tended strongly to focus on inequality, tax justice, and progressivity.
Core economy is defined as the economic activity, which is mostly underestimated as the non-market economy. As a result of certain concurrent studies, it is however estimated to be 25% of the economy of the USA with 1.91 trillion USD for the year 1998, which can’t be measured directly in spite of generating direct benefits. District bazaars and marketplaces and the street economy, an intersection point of the ones tired of suppression and tyranny of the Landowners and Sheikhdom, snowed under the sectarian conflicts, the ones feeling outcasted from the society, who would like to enjoy the benefits of modern life, the ones without the sufficient capital to establish a business or a regular business, the ones who would like to contribute to their families, the ones who are outside and excluded from the professional life; some of the ones are thugs and ramblers and lumpen, and the ones with no jobs and got nothing as defined as ‘Bosiacs’ by Maxim Gorki.
This paper attempts to trace and describe the role played by the government sector – the state – in promoting economic growth in Western societies since the Renaissance. One important conclusion is that the antagonism between state and market, which has characterised the twentieth century, is a relatively new phenomenon. Since the Renaissance one very important task of the state has been to create well‐functioning markets by providing a legal framework, standards, credit, physical infrastructure and – if necessary – to function temporarily as an entrepreneur of last resort. Early economists were acutely aware that national markets did not occur spontaneously, and they used “modern” ideas like synergies, increasing returns, and innovation theory when arguing for the right kind of government policy. In fact, mercantilist economics saw it as a main task to extend the synergetic economic effects observed within cities to the territory of a nation‐state. The paper argues that the classical Anglo‐Saxon tradition in economics – fundamentally focused on barter and distribution, rather than on production and knowledge – systematically fails to grasp these wider issues in economic development, and it brings in and discusses the role played by the state in alternative traditions of non‐equilibrium economics.
IT IS AXIOMATIC that journals like WORK STUDY leave politics severely alone. This is but sensible: whichever you praise, you will most certainly offend some of your readers. They are a cross‐section of the population and how they think (or vote) is their own business. It is not ours to inquire, nor, most certainly not to condemn.
The relationship between the size of state audit budgets, audit responsibilities, professional characteristics of staff, risk, and tax and expenditure limitations is…
The relationship between the size of state audit budgets, audit responsibilities, professional characteristics of staff, risk, and tax and expenditure limitations is explored. Bivariate relationships are examined and then a model is estimated which controls for size, complexity, financial risk factors, and political risk factors. This provides a framework for considering the incremental influence of specialized audit inputs. Both "brand names" and size have been used in past research to proxy for quality dimensions intended to differentiate the audit product provided by different suppliers. This research extends such work by considering characteristics of the auditing services as reflected by specific inputs and by using cost data rather than audit fee data. The states are observed to differ in their responses to financial and political factors by spending resources on peer review, continuing professional education, certifications of professional staff, and expertise in both the computer science area and in law. A positive association of cost and auditor differentiation, implicit in past audit fee literature is corroborated.