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11.
In this paper I describe how confidence in a software inspection can be obtained through calculating an estimate of its effectiveness. The method uses a Bayesian Belief Network to model the software inspection process and calculates the inference on how effective a particular inspection was. This technique was selected as it provides a means of initialising the model with inspectors' experience and has the ability to learn and optimise performance. This technique provides answers to some of the questions and limitations raised by current models used to predict inspection effectiveness. The application of the model to a major software project is discussed, covering the initial practitioner survey, model initialisation, model calibration and verification results obtained.  相似文献   
12.
There has been much talk of the need to build intermediate models of the expertise required preparatory to constructing a knowledge-based system in the legal domain. Such models offer advantages for verification, validation, maintenance and reuse. As yet, however, few such models have been reported at a useful level of detail. In this paper we describe a method for conceptualising legal domains as well as its application to a substantial fragment of the Dutch Unemployment Benefits Act (DUBA).We first discuss the intermediate models (called expertise models), then present a three-stage method for their construction, drawing on the CommonKADS work in knowledge acquisition, conceptual models of statute law, and the KANT method of knowledge analysis. Subsequently, we describe how these techniques were applied to the DUBA, and provide detailed examples of the resulting model. Finally, conclusions on the framework and guidelines are given as well as means of recording and presenting the various design choices.  相似文献   
13.
In this paper we present two simple, reliable and readily applicable methods for calibrating cantilevers and measuring the thickness of thin gold films. The spring constant calibration requires knowledge of the Young's modulus, density of the cantilever and resonant frequency. The thickness of thin gold layers was determined by measuring changes in the resonant frequency and Q-factor of beam shaped AFM cantilevers before and after coating.The techniques for measuring the spring constant and thin film thickness provide accuracy on the order of 10-15%.  相似文献   
14.
Alport syndrome (AS) is a hereditary renal disorder with no etiological therapy. In the preclinical Col4a3-/- model of AS, disease progression and severity vary depending on mouse strain. The sodium-glucose cotransporter 2 (SGLT2) is emerging as an attractive therapeutic target in cardiac/renal pathologies, but its application to AS remains untested. This study investigates cardiorespiratory function and SGLT2 renal expression in Col4a3-/- mice from three different genetic backgrounds, 129x1/SvJ, C57Bl/6 and Balb/C. male Col4a3-/- 129x1/SvJ mice displayed alterations consistent with heart failure with preserved ejection fraction (HFpEF). Female, but not male, C57Bl/6 and Balb/C Col4a3-/- mice exhibited mild changes in systolic and diastolic function of the heart by echocardiography. Male C57Bl/6 Col4a3-/- mice presented systolic dysfunction by invasive hemodynamic analysis. All strains except Balb/C males demonstrated alterations in respiratory function. SGLT2 expression was significantly increased in AS compared to WT mice from all strains. However, cardiorespiratory abnormalities and SGLT2 over-expression were significantly less in AS Balb/C mice compared to the other two strains. Systolic blood pressure was significantly elevated only in mutant 129x1/SvJ mice. The results provide further evidence for strain-dependent cardiorespiratory and hypertensive phenotype variations in mouse AS models, corroborated by renal SGLT2 expression, and support ongoing initiatives to develop SGLT2 inhibitors for the treatment of AS.  相似文献   
15.
ABSTRACT

Electric heat pumps feature prominently in projected energy transitions in the UK and elsewhere. Owing to their high electricity consumption, heat pumps are viewed as important targets for demand-side response (DSR). Findings are presented from a field trial of a new control system that aims to optimize heat pump performance, including under time-varying tariff conditions. The trial involved monitoring 76 properties with heat pumps, but without dedicated heat storage; 31 of these received the control system. Interviews were conducted with a subsample of 12 participants. The controller successfully evened out electricity demand over the day (reducing the evening peak), but this was associated with increased late night and daytime temperatures. Interview participants reported some disturbance owing to overnight heating and noise, as well as usability issues with the controller interface and hardware. These issues present risks to the future acceptability of such systems. While the system delivered short-term demand reductions successfully, longer-term demand shifting risked causing unacceptable disturbance to occupants. Future control systems could overcome some of the issues identified in this pioneering trial through more effective zoning, using temperature caps or installing dedicated heat storage, but these may either limit the available flexibility or be challenging to achieve.  相似文献   
16.
We describe PADUA, a protocol designed to support two agents debating a classification by offering arguments based on association rules mined from individual datasets. We motivate the style of argumentation supported by PADUA, and describe the protocol. We discuss the strategies and tactics that can be employed by agents participating in a PADUA dialogue. PADUA is applied to a typical problem in the classification of routine claims for a hypothetical welfare benefit. We particularly address the problems that arise from the extensive number of misclassified examples typically found in such domains, where the high error rate is a widely recognised problem. We give examples of the use of PADUA in this domain, and explore in particular the effect of intermediate predicates. We have also done a large scale evaluation designed to test the effectiveness of using PADUA to detect misclassified examples, and to provide a comparison with other classification systems.  相似文献   
17.
PCI Express(PCIe)是目前最新的高速串行连接技术之一,短期内将无所不在.由于它继承了全球相当普遍的PCI数据总线,因此这项技术具有快速带动PC及外围配备市场的威力和重大意义,因而受到相当大的重视.因各式各样的需求所致,PCIe足迹已遍布各种应用系统和市场中,未来还会出现在哪些应用上呢?本文将与您共同探讨一二.  相似文献   
18.
手机的使用模式相当简单:用户端口只要离PC数尺的距离,蓝牙手机就能自动进行电子邮件、相片、工作清单、联络人等数据的同步化.但有时用户对蓝牙的同步化与数据传输功能仍存在一些困惑,如PC虽然有蓝牙功能,但却经常无法连上手机如第一次就想让蓝牙功能顺利执行仍需要一些技巧,并不能立马使用等.本文详细为您讲述如何使智能手机实现数据同步化.  相似文献   
19.
Pathogen infection stimulates the fatty acid (FA) metabolism and the production of pro-inflammatory derivatives of FA. Barramundi, Lates calcarifer, was fed on a diet rich in preformed long-chain (?C20) polyunsaturated fatty acids (LC-PUFA) from fish oil (FO), to compare with diets containing high levels of C18 precursors for LC-PUFA – stearidonic (SDA) and γ-linolenic acid (GLA) – from Echium plantagineum (EO), or rapeseed oil (RO) rich in α-linolenic acid (ALA), but a poor source of LC-PUFA and their precursors. After 6 weeks, when growth rates were similar amongst the dietary treatments, a sub-lethal dose of Streptococcus iniae was administered to half of the fish, while the other half were maintained unchallenged and were pair-fed with the infected fish. Under a disease challenge situation, the tissue FA depots depleted at 3 days post-infection (DPI) and were then restored to their previous concentrations at 7 DPI. During the infection period, EO fish had a higher content of n3 and n6 PUFA in their tissues, higher n3:n6 PUFA ratio and reduced levels of the eicosanoids, TXB2 and 6-keto-PGF, in their plasma compared with RO fish. Fish fed on FO and EO had a longer lasting and enduring response in their FA and eicosanoid concentrations, following a week of bacterial infection, compared with those fed on RO. EO, containing SDA and GLA and with a comparatively higher n3:n6 PUFA ratio, proved more effective than RO in compensating for immunity stress.  相似文献   
20.
Kefir, a slightly acidic fermented milk, is produced by adding lactic acid bacteria and yeasts, in the form of grains, to milk. The bacteria and yeasts present in the kefir grains are known to vary widely. Selective growth media and morphological and biochemical characteristics were used for the isolation and identification of the microbes present in the grains from eight different sources in South Africa. The kefir grains were activated in milk for only 24 h to prevent any changes in the microbial population of the grains. The microbial numbers varied between 6.4 × 104 and 8.5 × 10 8  cfu/g on the media selective for the bacterial species and between 1.5 × 10 5 and 3.7 × 10 8   cfu/g on the media selective for the yeast species. The bacterial genera that were identified included Lactobacillus , Leuconostoc and Lactococcus and the yeast genera included Zygosaccharomyces , Candida and Saccharomyces . The distribution frequencies of the microbes in the different grains were determined and most of the grains were dominated by two microbial species. No pediococci, acetic acid bacteria or propionibacteria were detected.  相似文献   
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