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161.
162.
Petr Hájek Radko Mesiar 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2008,12(12):1239-1243
We investigate (quasi)copulas as possible truth functions of fuzzy conjunction which is not necessarily associative and present
some axiom systems for such fuzzy logics. In particular, we study an expansion of Łukasiewicz (infinite valued propositional)
logic by a new connective interpreted as an arbitrary quasicopula (and also by a new connective interpreted as the residuum
of the copula). Main results concern standard completeness. 相似文献
163.
Jaime Ortiz Óscar Palma Natalia González Santiago P. Aubourg 《European Journal of Lipid Science and Technology》2008,110(12):1127-1135
The flow ice system including ozone (OFI condition) was tested for slaughtering and storage (up to 16 days) of farmed rainbow trout (Oncorhynchus mykiss). Lipid damage analyses were carried out and compared to sensory acceptance and instrumental colour changes. Comparison to individuals processed with the flow ice system in the absence of ozone (FI condition) was undertaken. Rainbow trout slaughtered and chilled under FI and OFI conditions showed a low lipid damage development, according to lipid oxidation and hydrolysis events and lipid composition (polyunsaturated fatty acids, phospholipids and endogenous antioxidants) changes. Additionally, both icing conditions led to largely good quality and shelf life times and to the absence of changes in colour properties. It is concluded that flow ice as such, or including the presence of ozone, can be considered as ideal strategy to be employed as slaughtering and storage system during the commercialisation of the actual farmed species. The ozone presence has shown some profitable effects as leading to an extended shelf life time by quality retention of several sensory parameters; in contrast, some negligible negative effects could be observed on the secondary and tertiary lipid oxidation development. However, the oxidation values reached by individuals kept under OFI conditions cannot be considered as particularly high. 相似文献
164.
María Esther Diupotex-Chong Néstor J Cazzaniga Alejandra Hernández-Santoyo José Miguel Betancourt-Rule 《Biocell》2004,28(3):279-285
Mitotic chromosomes of the freshwater snail Pomacea patula catemacensis (Baker 1922) were analyzed on gill tissue of specimens from the type locality (Lake Catemaco, Mexico). The diploid number of chromosomes is 2n = 26, including nine metacentric and four submetacentric pairs; therefore, the fundamental number is FN = 52, No sex chromosomes could be identified. The same chromosome number and morphology were already reported for P. flagellata, i.e., the other species of the genus living in Mexico. The basic haploid number for family Ampullariidae was reported to be n = 14 in the literature; so, its reduction to n = 13 is probably an apomorphy of the Mexican Pomacea snails. Lanistes bolteni, from Egypt, also shows n = 13, but its karyotype is much more asymmetrical, and seems to have evolved independently from P. flagellata and P. patula catemacensis. The nominotypical subspecies, P. patula patula (Reeve 1856), is a poorly known taxon, whose original locality is unknown. A taxonomical account is presented here, and a Mexican origin postulated as the most parsimonious hypothesis. 相似文献
165.
J.L. Fernández-Martínez J.P. Fernández-Alvarez L.M. Pedruelo-González 《Computers & Geosciences》2008,34(3):213-225
A MATLAB®-based computer code that analyses the traveltime distribution and performs quality analysis at the pre-inversion stage for 2D transmission experiments is presented. The core tools of this approach are the so-called mean traveltime curves. For any general recording geometry, the user may select any pair of subsets of contiguous sources and receivers. The portion of the domain swept by the implied rays defines a zone of analysis, and for each source (receiver) the outcoming (incoming) ray fan is named a source (receiver) gather. The empirical mean traveltime curves are constructed, for each zone, by assigning the average and the standard deviation of the traveltimes in the gathers to the positions of the sources (receivers).The theoretical expressions assume isotropic homogeneous velocity inside each zone. The empirical counterparts use the observed traveltimes and make no assumptions. Isotropic velocity in each zone is inferred by least-squares fitting of the empirical mean traveltime curves. The user may refine the analysis considering different zones (multi-zone analysis). Initially the whole domain is modelled as a single zone. The procedure compares empirical versus theoretical curves. In addition, residuals can be plotted using source–receiver positions as plane coordinates. The results are used to unravel the possible presence of anomalous gathers, heterogeneities, anisotropies, etc. Depending on the kind of anomalies, velocity estimation and mean time residuals are different in the source and receiver gather curves.This software helps to grasp a better understanding of the data variability before the inversion and provides to the geophysicist an approximate zonal isotropic model and a range of velocity variation that can be used in the inverse problem as a priori information (regularization term). Its use is described through tutorial examples. A guided user interface leads the user through the algorithm steps. 相似文献
166.
S. Thió-Henestrosa J.J. Egozcue V. Pawlowsky-Glahn L.Ó. Kovács G.P. Kovács 《Computers & Geosciences》2008,34(12):1682-1696
A statistical analysis of compositional data based on the Aitchison geometry of the simplex requires an appropriate basis for representing the data. A simple and intuitive way of building such a basis employs a sequential binary partition of the compositional vector. The partition, together with some statistical summaries of the coordinates, or balances, can be represented in a dendrogram-type graph. In this paper we introduce an implementation of this methodology inside CoDaPack, which is freeware. An example with real data illustrates the use of the Balance-Dendrogram routine. 相似文献
167.
T Juhás 《Canadian Metallurgical Quarterly》1993,49(6):368-373
The very first experiences with implantation of 3 phakic anterior chamber lenses for high myopia correction are presented. After average 4 month follow up good stability and transparation of concave lenses type ZB5M were observed with accurately achieved correction postoperatively. 相似文献
168.
The health-care workers are known to be at risk of occupational transmission of blood-borne viruses. The goal of the investigation was to determine the prevalence of hepatitis C virus (HCV) antibody and the occupational risk of HCV transmission among personnel at the Central. Hospital for Infectious Diseases, Budapest, Hungary. Serum samples of 409 health-care workers were tested for antibody to HCV with second and third generation ELISA-s and anti-HCV positive samples were confirmed with Western Blot Line EIA. A total of 10 (2.4%) of the health-care workers were confirmed to be anti-HCV positive. The prevalence of anti-HCV increased with advancing age: zero under 20 yr age group (N = 0/15), 0.9% in 21-30 yr age group (N = 1/112), 1.8% in 31-40 yr age group (N = 2/111), 3.1% in 41-50 yr age group (N = 3/96) and 4.0% in above 50 yr age group (N = 3/75). We found anti-HCV positive hospital worker in 9 out of 17 departments. The prevalence of hepatitis C antibody was 7.1-1.9% among the personnel of internal departments, pathology, intensive care unit and pediatric departments. No anti-HCV positive health-care worker was found in the surgery and laboratories. None of the physicians tested was seropositive for HCV. Eight of the nurses, one of the sanitary personnel and one pathological technician were seropositive for HCV. Two nurses developed a chronic C hepatitis after a needlestick accident. CONCLUSIONS: 1. The hospital personnel is at risk for HCV infection. 2. The occupational risk of HCV infection increases with age but the risk is considerable lower than that of hepatitis B infection. 3. The occupational risk is highest among the workers of the chronic internal department, pathology and intensive care unit. 4. The nurses are at higher risk of HCV infection than the physicians. 5. The needlestick injury is associated with an increased risk for acquiring HCV infection. 相似文献
169.
170.
Twenty-eight experienced handlers, considered the best in two transport companies, were interviewed using a questionnaire consisting of partially closed-ended questions. They had to assess 20 videotape handling sequences showing two different handling methods to determine, for 10 factors and overall, which one was the best. They were asked about the inportance of these factors in their choices of the best method. The aims of the study were to verify whether there was a consensus among experienced handlers as to what was a good handling method and to identify the factors taken into consideration by them. Results show the lack of consensus on the best methods. Handlers favor different strategies depending on the worjk context and their own priorities. 相似文献