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Big Problem (big + problem)
Selected AbstractsSteam, hot air, and small change: Matthew Boulton and the reform of Britain's coinageECONOMIC HISTORY REVIEW, Issue 3 2003George Selgin This article challenges the claim that Great Britain solved its ,big problem of small change' (the problem of keeping decent low-denomination coins in circulation) by embracing Matthew Boulton's steam-based coining technology. Evidence from Great Britain's commercial token episode (1787,97) shows that a successful small change system depended, not on the motive power employed in coining, but on the quality and consistency of coin engravings and on having means for systematically withdrawing worn coins. The Tower Mint failed to solve Great Britain's small change problem, not because its equipment was old-fashioned, but because its policies and constitution were flawed. [source] Experimental study of a doubly-fed rotary frequency converterELECTRICAL ENGINEERING IN JAPAN, Issue 4 2010Yasutoshi Takemoto Abstract Wind power generation using an unlimited, natural energy has been getting attention regarding environmental issues in recent years, and the installed capacity of wind power generation system is increasing at a rapid pace, resulting in deterioration of power quality especially in frequency and voltage. This fact will be a big problem in restricting large capacity of wind farms. This paper proposes a new frequency converter: rotary frequency converter (RFC) to moderate the electric output from wind generation, which is to be installed between a set of wind generators and a grid, providing a smoothed electric output, promoting the wind power generation introduction. This mainly consists of a synchronous machine and the adjustable-speed machine. Independent controls of input/output voltage, active power, and reactive power offer electrical separation between the two networks. Experimental study of a prototype model and its characteristics, especially dynamic control, is discussed in this paper. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 170(4): 26,34, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20922 [source] How to prevent inventory fraudJOURNAL OF CORPORATE ACCOUNTING & FINANCE, Issue 4 2003J. Ralph Byington Inventory fraud is a big problem. And it's tough to uncover. So how can you prevent and detect inventory fraud? Are you confident that the inventory count and amount are actually the same? © 2003 Wiley Periodicals, Inc. [source] Quantitative analysis of the microscale of auxetic foamsPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 3 2005N. Gaspar Abstract The auxetic foams first produced by Lakes have been modelled in a variety of ways, each model trying to reproduce some observed feature of the microscale of the foams. Such features include bent or broken ribs or inverted angles between ribs. These models can reproduce the Poisson's ratio or Poisson's function of auxetic foam if the model parameters are carefully chosen. However these model parameters may not actually reflect the internal structure of the foams. A big problem is that measurement of parameters such as lengths and angles is not straightforward within a 3-d sample. In this work a sample of auxetic foam has been imaged by 3-d X-ray computed tomography. The resulting image is translated to a form that emphasises the geometrical structure of connected ribs. This connected rib data are suitably analysed to describe both the microstructural construction of auxetic foams and the statistical spread of structure, that is, the heterogeneity of an auxetic foam. From the analysis of the microstructure, observations are made about the requirements for microstructural models and comparisons made to previous existing models. From the statistical data, measures of heterogeneity are made that will help with future modelling that includes the heterogeneous aspect of auxetic foams. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] BSE still a big problem -EU had 3000 cases in 1999AUSTRALIAN VETERINARY JOURNAL, Issue 4 2000Jouko Koppinen No abstract is available for this article. [source] Analyzing sales for better cash flow managementJOURNAL OF CORPORATE ACCOUNTING & FINANCE, Issue 1 2003Rob Reider Do you sometimes get the feeling that your sales function is in business for itself,instead of supporting the company? That means big problems for managing cash flow, warn the authors of this article. What steps must you take to make sales an integral part of cash flow planning? The authors provide a detailed how-to guide for you to use. © 2003 Wiley Periodicals, Inc. [source] The limitations of randomized controlled trials in predicting effectivenessJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 2 2010Nancy Cartwright PhD FBA Abstract What kinds of evidence reliably support predictions of effectiveness for health and social care interventions? There is increasing reliance, not only for health care policy and practice but also for more general social and economic policy deliberation, on evidence that comes from studies whose basic logic is that of JS Mill's method of difference. These include randomized controlled trials, case,control studies, cohort studies, and some uses of causal Bayes nets and counterfactual-licensing models like ones commonly developed in econometrics. The topic of this paper is the ,external validity' of causal conclusions from these kinds of studies. We shall argue two claims. Claim, negative: external validity is the wrong idea; claim, positive: ,capacities' are almost always the right idea, if there is a right idea to be had. If we are right about these claims, it makes big problems for policy decisions. Many advice guides for grading policy predictions give top grades to a proposed policy if it has two good Mill's-method-of difference studies that support it. But if capacities are to serve as the conduit for support from a method-of-difference study to an effectiveness prediction, much more evidence, and much different in kind, is required. We will illustrate the complexities involved with the case of multisystemic therapy, an internationally adopted intervention to try to diminish antisocial behaviour in young people. [source] Design, Preparation, and Characterization of Graded YSZ/La2Zr2O7 Thermal Barrier CoatingsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 6 2010Hongfei Chen Large-area spallation and crack formation during service are big problems of plasma-sprayed thermal barrier coatings (TBCs), owing to their weak bond strengths and high residual stresses. Functional gradient TBCs with a gradual compositional variation along the thickness direction are proposed to mitigate these problems. In this paper, a six-layer structured TBC composed of Y2O3 partially stabilized ZrO2 (YSZ) and La2Zr2O7 (LZ), was prepared by plasma spraying with dual powder feeding ports. This coating had a gradient composition and function. Thermal conductivity of the coating was comparable with that of a single LZ coating while the coefficient of thermal expansion was nearly equal to that of YSZ single coating. The experiment was conducted to compare the thermal shock resistance of a graded coating with a conventional YSZ/LZ double-layer system. Changes in weight and morphology of specimens before and after thermal shock tests were analyzed. Results demonstrated that the thermal shock resistance of the graded coating was superior to the double-layer coating. Typically, a barely visible pimple-like spallation was present on the surface of the graded coating after 21 cycles. On the other hand, obvious delamination was observed for a double-layer coating after six to seven cycles. Special focus was also placed on a comparative investigation of stresses that are closely related to spallation via the use of numerical simulation. [source] | ||||||||||