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This paper reviews the current state of industry with regard to the introduction of software metrics. It discusses the benefits that organizations have derived from metrication, it looks at why organizations have sought to introduce metrics programmes, how they have gone about introducing those programmes and the problems that they have encountered during implementation. The review found that, on the whole, only the sanitized aspects of metrics experiences have actually been published. This seems to be especially the case with respect to practitioner resistance. Very few organizations admit to having encountered resistance during the introduction of a metrics programme. The paper also includes the results of a pilot study, conducted by the first author, which examines the attitudes that developers hold towards the introduction of software metrics. The key findings of this pilot study are that positive attitudes to metrics correlate highly with levels of education and to job satisfaction. 相似文献
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AM De Mattos MA Head J Everett J Hosenpud R Hershberger A Cobanoglu G Ott R Ratkovec DJ Norman 《Canadian Metallurgical Quarterly》1994,57(4):626-630
To determine if cardiac allograft outcome is improved among patients with fewer HLA-DR mismatches with their donors, we studied 132 recipients of a primary cardiac allograft who were transplanted between December 1985 and December 1991. These recipients and their donors all had high-confidence-level serological HLA-DR typing, previously shown to correlate highly with DNA DR typing. Patients were divided in two groups based on the HLA-DR mismatch with their donors. Group I consisted of 78 patients with 1 or zero DR mismatch and group II of 54 patients with 2 DR mismatches. Allograft outcome measurements included incidence of moderate rejection, incidence of allograft vasculopathy at 12 months, cardiac function measured as left ventricular ejection fraction (LVEF) and cardiac index (CI), and actuarial graft survival up to 7 years. Groups I and group II were not different with regard to recipient age, donor age, ischemia time, pulmonary vascular resistance, sex, or PRA greater than 0%. Group II had a higher incidence of moderate rejection on the first-week biopsy (47% vs. 25%, P = 0.019), and during the first month (84% vs. 58%, P = 0.006), but no difference was found in frequency of rejection from months 2 to 12. LVEF was not different in the groups at any point. CI was better in group I at 12 months (2.76 vs. 2.5, P = 0.03). No statistically significant difference was found in incidence of allograft vasculopathy (17% vs. 26%, P = 0.204). Actual graft survival at 1 year was better for group I (91% vs. 74%, P = 0.008), and actuarial graft survival at 6 years also favored group I (76% vs. 56%, P = 0.04). Using high-confidence-level serological HLA-DR typing assignments we demonstrated that HLA-DR mismatching correlates highly with cardiac allograft outcome. Implications are that heart transplant survival could be improved if prospective matching were feasible and prioritized or if immunosuppression were tailored to the HLA-DR match. 相似文献
4.
N. R. Bohidar Norman R. Bohidar Nicholas R. Bohidar 《Drug development and industrial pharmacy》1994,20(5):815-839
A discordant observation is a data point whose value is drastically different from that of the rest of the members in the data set. In the context of content uniformity experiments, however, a discordant observation arises in two ways: (i) when the value of an observation is markedly distant from that of the other data points even though it is within the required compendial range, and (ii) when the value of an observation is outside the permissible compendial range. Several statistical tests for detecting one or more discordant observations are presented. Since discordancy distorts the symmetricity of the data, several tests of symmetricity are provided. Tests for detection of group discordancy induced by discordant samples are also included. The compendial requirements are explained in statistical terms. The impact of discordant observations on compendial compliance requirements is assessed. The statistical basis of the construction of compendial limits as well as the assumptions implicit in the construction is elaborated. The results of the statistical analysis of three content uniformity studies are appropriately interpreted. 相似文献
5.
Norman F. Haard Nancy Kariel Gene Herzberg L. A. Woodrow Feltham Karl Winter 《Journal of the science of food and agriculture》1985,36(4):229-241
Fish silage was prepared from 96.5% offal obtained from Atlantic cod fillet processing and 3.5% (by wt) formic acid. The fish silage became an homogeneous liquid of low viscosity in 36–58 h at 20°C; however, the oil and protein components continued to be hydrolysed for several months. Addition of formaldehyde to fish silage (0.25 or 0.39% by wt) after liquefaction was complete, served to prevent continued protein hydrolysis and oxidative rancidity of the oil. It also decreased the development of ‘off-odours’, and the formation of total volatile bases. Fish silage was readily absorbed by hay at a ratio of 1.5 parts silage to 1.0 parts hay by weight; the product is referred to as ‘haylage’. Voluntary intake by wethers of ‘haylage’ prepared from de-oiled, formaldehyde-treated fish silage was better than for ‘haylage’ prepared from untreated fish silage. The crude protein content of ‘haylage’ rations was more than satisfactory for fattening lambs, although the energy content of ‘haylage’ rations may be a limiting factor. Retention of fish oil in the silage to increase the energy content of rations was unsuccessful because voluntary feed intake was depressed. The addition of formaldehyde to fish silage is advantageous when the product is to be fed to ruminant livestock since protein and lipid degradation in the feed, and also possibly in the rumen, are minimised and voluntary intake of ‘haylage’ by sheep is increased. 相似文献
6.
First available appraisals for 67,644 Jersey cows were used to estimate relative magnitudes of additive and selected sources of nonadditive genetic variance and covariance for 13 type traits scored linearly from 50 to 99 points. Covariances among four types of relatives were used to estimate components of genetic variance and covariance for each of the 13 traits. Direct additive, direct dominance, and additive maternal genetic variances and the direct-maternal additive genetic covariance were estimated using covariances among paternal half-sibs, full-sibs, daughters and dams, and maternal half-sibs. Estimates of additive genetic variance were 11 to 36% of variance within herd-appraiser subclasses with largest values for stature, strength, rump angle, rump width, and udder depth. Dominance components were two to four times the magnitude of additive components for dairy character, rump width, fore udder, rear udder height, rear udder width, and suspensory ligament but much smaller for other traits. Maternal effects and the direct-maternal additive genetic covariance appeared small for all linear type traits. 相似文献
7.
Blair J.D. Correale A. Jr. Cranford H.C. Dombrowski D.A. Erdelyi C.K. Hoffman C.R. Lamphere J.L. Lang K.W. Lee J.K. Mullen J.M. Norman V.R. Oakland S.F. 《Solid-State Circuits, IEEE Journal of》1989,24(6):1647-1655
The authors describe a 9.02×9.02-mm chip built in 1-μm CMOS with two levels of metal and an additional mask level for fabricating capacitors. It contains both analog and digital circuits and has provisions for self-test. The function includes the transmitter, receiver, protocol handler, an microprocessor, as well as interfaces for RAM/ROM storage, IBM PC bus, IBM PS/2 bus, IBM 3174 bus, and Motorola 68000 bus. The physical design terrains are formed by 24K circuits of standard cell gates, a 10K-circuit equivalent hand-honed custom microprocessor, and an analog macro. The chip operates from a single 5-V supply, and the power consumption is 0.8 W nominal at 16 Mb/s. The chip can also be operated at 4 Mb/s 相似文献
8.
K M Cooper L Ribeiro P Alves V Vozikis S Tsitsamis G Alfredsson T L?vgren M Tuomola H Takalo A Iitia S S Sterk M Blokland D G Kennedy 《Food Additives & Contaminants》2003,20(9):804-812
Many zeranol immunoassay test kits cross-react with toxins formed by naturally occurring Fusarium spp. fungi, leading to false-positive screening results. This paper describes the evaluation and application of recently published, dry reagent time-resolved fluoroimmunoassays (TR-FIA) for zeranol and the toxin alpha-zearalenol. A ring test of bovine urine fortified with zeranol and/or alpha-zearalenol in four European Union National Reference Laboratories demonstrated that the TR-FIA tests were accurate and robust. The alpha-zearalenol TR-FIA satisfactorily quantified alpha-zearalenol in urine fortified at 10-30 ng ml(-1). The specificity-enhanced zeranol TR-FIA accurately quantified zeranol in the range 2-5 ng ml(-1) and gave no false-positive results in blank urine, even in the presence of 30 ng ml(-1) alpha-zearalenol. Zeranol TR-FIA specificity was demonstrated further by analysing incurred zeranol-free urine samples containing natural Fusarium spp. toxins. The TR-FIA yielded no false-positive results in the presence of up to 22 ng ml(-1) toxins. The performance of four commercially available zeranol immunoassay test kits was more variable. Three kits produced many false-positive results. One kit produced only one potential false-positive using a protocol that was longer than that of the TR-FIA. These TR-FIAs will be valuable tools to develop inspection criteria to distinguish illegal zeranol abuse from contamination arising from in vivo metabolism of Fusarium spp. toxins. 相似文献
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