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Hannes Verlinde Martine De Cock Raymond Boute 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2006,36(3):679-684
As opposed to quantitative association rule mining, fuzzy association rule mining is said to prevent the overestimation of boundary cases, as can be shown by small examples. Rule mining, however, becomes interesting in large databases, where the problem of boundary cases is less apparent and can be further suppressed by using sensible partitioning methods. A data-driven approach is used to investigate if there is a significant difference between quantitative and fuzzy association rules in large databases. The influence of the choice of a particular triangular norm in this respect is also examined. 相似文献
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Martine Decloux Manuel Dornier & Isabelle Gratius 《International Journal of Food Science & Technology》1996,31(2):153-166
Gum arabic is a natural gum exuded mainly by the trees Acacia senegal , currently used in the food industries for its emulsifying, thickening and stabilizing properties. Its present processing includes various operations providing a quite turbid product. Crossflow microfiltration could be interesting for the clarification and the cold-pasteurization of the gum arabic solutions. Several experiments were therefore made with the crossflow microfiltration unit at ENSIA, using two different systems: the classical one (without permeate circulation), and the co-current permeate flow system (CCPF) allowing the exploration of the low transmembrane pressures range. With gum arabic solutions of 0.17g solids g−1 solution and 70°C, the best results after 60 min of filtration (105.7 L h−1 m−2 , 4.4% of solids retention and 83.4% of clarification) were obtained with the CCPF system at low transmembrane pressure and high crossflow velocity (0.3 bar and 7.5ms−1 ). 相似文献
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Electron Spin Resonance, Differential Scanning Calorimetry and rheological techniques have been used to study the physical
changes induced by temperature in lard and in the solid and liquid fractions obtained by fractionation of lard at 15 C. The
mobilization process of a C18 fatty acid nitroxide derivative dispersed in the molten fat has been observed in the temperature
range −50 to +70 C.
The mobilization of the probe seemed to be concomitant with the melting of the low melting point glycerides. Above this temperature,
all the probes were in the liquid phase and their mobility reflected the viscosity of their liquid environment, or the viscosity
of the bulk fat when crystal was no longer present.
Probe mobility was temperature dependent, and it was identical for the three fats at the same temperature, despite their different
triglyceride compositions. 相似文献
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This article is concerned with the l2-approximation of a given transfer function f by a rational one whose order is prescribed. We show that the sum of the indices of the critical points of the criterion is generically equal to 1, and in particular does not depend on f. 相似文献
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Juice-extracted grass pellets and sodium bicarbonate for cows fed timothy silage of two chop lengths
Eighteen multiparous Holstein cows in midlactation were used in a switchback design trial to evaluate the effect of chop length (3 or 30 mm) of timothy grass silage, containing less than 30% ADF and treated with formic acid, on DMI and cow performance. Within chop length, addition of NaHCO3 (2% of DMI) or the replacement of 30% of silage DM with juice-extracted grass pellets was also evaluated. Cows were fed a TMR composed of 90% silage and 10% concentrate. Silage preservation characteristics were not different between chop lengths. The DMI and apparent digestibility were similar among treatments. Yields of 4% FCM (24.9 vs. 22.7 kg/d), fat (1.03 vs. .93 kg/d), and protein (.83 vs .77 kg/d) were higher with the short chopped silage. Milk protein, milk NPN content, and serum urea were higher for cows fed long chopped silage. Yields of milk and milk constituents were not affected by the addition of juice-extracted grass pellets or NaHCO3. Fat percentage and fatty acid composition of milk remained unchanged by treatments. Reduction of particle size, from 30 to 3 mm, of timothy grass, treated with formic acid at harvest and using compaction at ensiling in bag silos, did not affect silage conservation characteristics but did improve milk, fat, and protein yields when cows were fed high silage diets. 相似文献
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Social support and survival among women with breast cancer 总被引:1,自引:0,他引:1
BACKGROUND: Two recently reported randomized trials, one among patients with advanced breast cancer and the other among patients with early stage melanoma, suggested that social support may affect survival favorably. This study assesses relationships of social support indicators with 7-year survival among women diagnosed with localized or regional stage breast cancer. METHODS: All newly diagnosed patients with surgically treated localized or regional disease in seven Quebec City hospitals in 1984 were considered for this analysis. Among 235 eligible patients, 224 (95%) participated in a home interview 3 months after surgery. This interview provided information on the use of confidants in the 3 months after surgery. Data on disease and treatment characteristics were abstracted from patients' medical records. RESULTS: Compared with women who used no confidant in the 3 months after surgery, the hazard ratio for the 7-year period was 0.61 (95% confidence interval [CI], 0.33-1.12) among those who had used at least one confidant, 0.54 (95% CI, 0.28-1.06) in women who used two or more types of confidant, and 0.51 (95% CI, 0.22-1.18) among those whose confidants included either physician or nurse. These results were adjusted for age, presence of invaded axillary lymph nodes, adjuvant radiotherapy, and adjuvant systemic therapy (hormone or chemotherapy). CONCLUSION: These results support the view that social support may be associated with longer survival among women with localized or regional stage breast cancer. 相似文献
10.
BACKGROUND: Despite numerous studies of partial mastectomy and psychologic morbidity in the first 24 months following surgery, little is known about the long term psychosocial repercussions of partial and total mastectomy. METHODS: The effect of the type of mastectomy on psychologic adjustment was assessed among 124 breast carcinoma survivors, 47 of whom underwent partial mastectomy and 77 of whom underwent total mastectomy, 8 years after initial treatment. Interviews were also conducted 3 and 18 months after surgery. Psychologic distress was assessed using the Psychiatric Symptom Index. Other outcomes included physical symptoms, patients' perceptions of their own health, satisfaction with the type of surgery performed and with the appearance of the scar, and marital and sexual adjustments. RESULTS: No statistically significant differences between partial and total mastectomy were observed with respect to long term quality of life. Age at diagnosis modified the relation between the type of mastectomy and psychologic distress in both the short term and the long term (P = 0.04). Among women younger than 50 years, partial mastectomy appeared to be protective against distress when compared with total mastectomy. In contrast, among women age 50 years or older, partial mastectomy was associated with higher psychologic distress levels at all interviews. CONCLUSIONS: Assessed globally, partial and total mastectomy appear to be equivalent treatments in terms of patients' long term quality of life. However, both short term and long term distress levels after partial and total mastectomy may depend on patients' age at diagnosis. The findings of this study suggest that the increased use of partial mastectomy may lessen the negative effects of breast carcinoma on younger survivors' quality of life. Nevertheless, total mastectomy may be an appropriate initial treatment for some women who truly choose it. 相似文献