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31.
Don Kelleher 《Information Systems Journal》1995,5(2):137-157
Abstract. An Information Systems Methodology is usually presented as a sequential set of tasks — planning, analysis, design and construction — resulting in a new business application. This classical 'forward-engineering' approach must be adapted to changing business needs — business process redesign, quality management, process and systems templates, advanced technologies, application packages, the reuse of existing information systems resources, and rapid delivery cycles. Using the most general concept of a Business Programme, this paper describes a methodological approach incorporating these modern themes that is qualitatively and quantitatively different from the classical model. It provides a framework for the integration of otherwise independent methodologies, and shows how an entire programme can be formulated, planned and executed. An example is provided, and the approach is justified. 相似文献
32.
Although reticulocyte counts can be reliably performed for up to 48 h after storage in EDTA, it is unclear whether this is applicable to the pediatric age group. In order to evaluate this, manual reticulocyte counts were performed on 20 specimens from pediatric patients stored at 4 degrees C for up to 24 h post collection. Samples were evaluated at 1-3, 6, 12, 18, and 24 h after storage in EDTA vacutainer tubes at 4 degrees C. The age of the subjects ranged from 1 day to 9 years with a median age of 3 years. Patients' reticulocyte counts ranged from 0 to 27% (5.89 +/- 7.21). No clinically significant changes were evident in the reticulocyte count over 24 h after specimen collection. The mean of the 20 specimens at 1-3 h was 5.50 and at 24 h was 5.40 (P > .05). The standard deviation of the mean values ranged from 7.03 to 7.26 (P > .05). The results indicate that reticulocyte counts may be performed on previously drawn blood held at 4 degrees C for up to 24 h post collection in a pediatric population without significant difference from baseline values. 相似文献
33.
Riedel S.A. Harris G.F. Jizzine H.A. 《IEEE engineering in medicine and biology magazine》1992,11(4):42-47
Results of tests undertaken to identify which measures of seated posture control are most effective in two areas, distinguishing differences in the x and y direction control strategies for a given task and distinguishing differences in overall control strategies for pairs of different tasks, are presented. The test platform, calibration tests, test protocol, and data analysis method are described. The results of statistical analyses performed on the data are summarized 相似文献
34.
The reaction of LaNi5 with Cu powder during sintering at high temperature was examined in order to obtain better conductivity and ductility. Pressurized and forged copper-LaNi5 pellets were investigated by optical metallography, DTA, XRD and TEM. The need for heat treatment after pressing and/or forging is vital to obtain good diffusion bonding between the copper particles and to improve the material strength. No interaction between La, Ni and Cu were observed after heating at 1173 K but a very stable La2O3 phase was created around the LaNi5 particle. Rolling up to 85% reduction showed good ductility. 相似文献
35.
36.
Low-temperature interface reaction in aluminium-silicon carbide particulate composites produced by mechanical alloying 总被引:1,自引:0,他引:1
An experimental investigation has been carried out on the reaction that takes place between 3 and 20 μm SiC particles and
the aluminium alloy 1050 matrix of composite materials prepared by a mechanical alloying process. The work is different from
that undertaken by other researchers in that the SiC-Al interface reaction has been studied in the temperature range 853–933
K, i.e., with the matrix initially in the solid state. Differential thermal analysis, X-ray diffraction and scanning electron
microscopy all show that the SiC-Al reaction initiates in the solid state at temperatures as low as 883 K. The reaction produces
Al4C3 and Si, the latter entering into solid solution in the aluminium matrix. At temperatures exceeding 903 K, the reaction
produces a liquid phase and at this stage the speed of the interface reaction increases significantly. The results are discussed
in terms of Al-Si-C metastable equilibrium and the kinetics of the reaction.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
37.
Tempest Philip R.; White Patricia; Williamson E.Diane; Titball Richard W.; Kelly David C.; Kemp Graham J.L.; Gray Peter M.D.; Forster Simon J.; Carr Frank J.; Harris William J. 《Protein engineering, design & selection : PEDS》1994,7(12):1501-1507
We have used the technique of antibody reshaping to producea humanized antibody specific for the a toxin of Clostridiumperfringens. The starting antibody was from a mouse hybridomafrom which variable (V) region nucleo-tide sequences were determined.The complementarity-determining regions (CDRs) from these Vregions were then inserted into human heavy and light chainV region genes with human constant region gene fragments subsequentlyadded. The insertion of CDRs alone into human frameworks didnot produce a functional reshaped antibody and modificationsto the V region framework were required. With minor frameworkmodifications, the affinity of the original murine mAb was restoredand even exceeded. Where affinity was increased, an alteredbinding profile to overlapping peptides was observed. Computermodelling of the reshaped heavy chain V regions suggested thatamino acids adjacent to CDRs can either contribute to, or distort,CDR loop conformation and must be adjusted to achieve high bindingaffinity. 相似文献
38.
Data from the Cancer Registry of Slovenia were used in a cohort study to determine whether the incidence of second primary cancers in patients with first primary breast cancer differs from the incidence expected in the general population. Special interest was given to long-term survivors. The expected numbers of second primary cancers were calculated by multiplying the number of appropriate person-years at risk by the corresponding age- and calendar-period-specific cancer incidence rates for women in Slovenia. The risk of a second primary cancer was expressed as the standardized incidence ratio (SIR). Of the 8,917 patients newly diagnosed in the period 1961-85 and followed-up to the end of 1994, 547 (6.2 percent) developed second primary cancers, whereas 410 (4.7 percent) were expected (SIR = 1.3, 95 percent confidence interval [CI] = 1.2-1.4). The risk was higher among younger patients. In long-term survivors, the risk was increased significantly for second primary cancer of the breast (SIR = 1.4, CI = 1.1-1.7), lung cancer (SIR = 1.6, CI = 1.1-2.3), melanoma (SIR = 2.7, CI = 1.5-4.4) and non-melanoma skin cancers(SIR = 2.0, CI = 1.6-2.4), corpus uteri cancer(SIR = 1.6, CI = 1.2-2.1), ovarian cancer(SIR = 2.3, CI = 1.7-3.0), and thyroid cancer (SIR = 2.5, CI = 1.2-4.6). Our results confirm the findings of several cohort studies carried out in Europe, the United States, and Japan, indicating that breast cancer patients should be monitored carefully for the occurrence of second primary cancers. 相似文献
39.
Tucker Don M.; Luu Phan; Frishkoff Gwen; Quiring Jason; Poulsen Catherine 《Canadian Metallurgical Quarterly》2003,112(4):667
Functional neuroimaging suggests that limbic regions of the medial frontal cortex may be abnormally active in individuals with depression. These regions, including the anterior cingulate cortex, are engaged in both action regulation, such as monitoring errors and conflict, and affect regulation, such as responding to pain. The authors examined whether clinically depressed subjects would show abnormal sensitivity of frontolimbic networks as they evaluated negative feedback. Depressed subjects and matched control subjects performed a video game in the laboratory as a 256-channel EEG was recorded. Speed of performance on each trial was graded with a feedback signal of A, C, or F. By 350 ms after the feedback signal, depressed subjects showed a larger medial frontal negativity for all feedback compared with control subjects with a particularly striking response to the F grade. This response was strongest for moderately depressed subjects and was attenuated for subjects who were more severely depressed. Localization analyses suggested that negative feedback engaged sources in the anterior cingulate and insular cortices. These results suggest that moderate depression may sensitize limbic networks to respond strongly to aversive events. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
S. P. Ashburn M. C. Öztürk J. J. Wortman G. Harris J. Honeycutt D. M. Maher 《Journal of Electronic Materials》1992,21(1):81-86
Titanium and cobalt germanides have been formed on Si (100) substrates using rapid thermal processing. Germanium was deposited
by rapid thermal chemical vapor deposition prior to metal evaporation. Solid phase reactions were then performed using rapid
thermal annealing in either Ar or N2 ambients. Germanide formation has been found to occur in a manner similar to the formation of corresponding silicides. The
sheet resistance was found to be dependent on annealing ambient (Ar or N2) for titanium germanide formation, but not for cobalt germanide formation. The resistivities of titanium and cobalt germanides
were found to be 20 μΩ-cm and 35.3μΩ-cm, corresponding to TiGe2 and Co2Ge, respectively. During solid phase reactions of Ti with Ge, we have found that the Ti6Ge5 phase forms prior to TiGe2. The TiGe2 phase was found to form approximately at 800° C. Cobalt germanide formation was found to occur at relatively low temperatures
(425° C); however, the stability of the material is poor at elevated temperatures. 相似文献