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11.
This paper presents several randomised algorithms for generating paths in large models according to a given coverage criterion. Using methods for counting combinatorial structures, these algorithms can efficiently explore very large models, based on a graphical representation by an automaton or by a product of several automata. This new approach can be applied to random exploration in order to optimise path coverage and can be generalised to take into account other coverage criteria, via the definition of a notion of randomised coverage satisfaction. Our main contributions are a method for drawing paths uniformly at random in composed models, i.e. models that are given as products of automata, first without and then with synchronisation; a new efficient approach to draw paths at random taking into account some other coverage criterion. Experimental results show promising agreement with theoretical predictions and significant improvement over previous randomised approaches. This work opens new perspectives for future studies of statistical testing and model checking, mainly to fight the combinatorial explosion problem.  相似文献   
12.
The antioxidative activity of α-tocopherol in oil is necessary for the inhibition of lipid peroxidation. If no regeneration of antioxidants is possible in foods, oxidation products are formed to a measurable extent. The aim of this study was to investigate oxidation products of α-tocopherol in plant oil. The oxidation of α-tocopherol in plant oil leads to α-tocopherolquinone and to two epoxides (α-tocopherolquinone-2,3-epoxide, α-tocopherolquinone-5,6-epoxide). These three reaction products were identified and quantified in plant oil. The 2,3-epoxide is formed at lower temperatures (90°C) whereas at high temperatures (180–220°C) only the 5,6-epoxide appears. The kinetics show that the 5,6-epoxide is produced as long as α-tocopherol is present. With longer reaction times the concentration of the 5,6-epoxide starts to decrease. α-Tocopherolquinone is found at substantially lower concentrations.  相似文献   
13.
In new approaches based on adaptive neuro-fuzzy systems (ANFIS) and analytical method, heart rate (HR) measurements were used to estimate oxygen consumption (VO2). Thirty-five participants performed Meyer and Flenghi's step-test (eight of which performed regeneration release work), during which heart rate and oxygen consumption were measured. Two individualized models and a General ANFIS model that does not require individual calibration were developed. Results indicated the superior precision achieved with individualized ANFIS modelling (RMSE = 1.0 and 2.8 ml/kg min in laboratory and field, respectively). The analytical model outperformed the traditional linear calibration and Flex-HR methods with field data. The General ANFIS model's estimates of VO2 were not significantly different from actual field VO2 measurements (RMSE = 3.5 ml/kg min). With its ease of use and low implementation cost, the General ANFIS model shows potential to replace any of the traditional individualized methods for VO2 estimation from HR data collected in the field.  相似文献   
14.
The ability to predict and control organic decomposition of a material under arbitrary thermal treatments is one of the main objectives of thermogravimetric studies. The development of this ability provides significant potential to ensure reliability and reproducibility for a given processing method and can be used in planning optimized thermal treatment strategies. Based on this report, the master sintering curve theory has been successfully extended to similar kinetically controlled phenomena. The theory has been applied to organic decomposition reaction kinetics to develop a master organic decomposition curve. The fundamental kinetics are assumed to be governed by an Arrhenius-type reaction rate, making master sintering and decomposition curves analogous to one another. The formulation and construction of a master decomposition curve are given in this paper. Simultaneous thermogravimetric and differential thermal analysis of a low-temperature co-fire glass/ceramic dielectric tape (Dupont 951 Green TapeTM) is analyzed and used to demonstrate this new concept. The results reveal two independent organic decomposition reactions, the first occurring at ≈245°C and the second at ≈365°C. The analysis is used to produce a master decomposition curve and to calculate the activation energy for these reactions, at 86±6 and 142±4 kJ/mol, respectively. In addition, the weight loss of product and the rate of decomposition can be predicted under varying thermal paths (time–temperature trajectories) following a minimal set of preliminary experiments.  相似文献   
15.
Although libraries maintain collections of material on computer disks in climate controlled environments, a significant amount of digital heritage is in private collections. In this study we compared the outcomes of creating disk images of the State Library of South Australia’s born digital collections with those of a private collector to gauge the effect of long term storage conditions. The failure rates of both collections give cause for concern, and the results from the private collection are alarming.  相似文献   
16.
Image cytometry is an important technique in affordable healthcare and cellular research. Some efforts toward establishing a personal, low-cost cytometer have been described in the literature. However, a self-assembled fluorescence microscope requires software for cytometric analysis. There are some open-source image-based software analysis applications available. However, for a quantitative analysis of images, software that can generate data comparable to those of previously evaluated cytometric analyses programs is required. Hence, the aim of this study is to compare results of a commercially available image cytometry program to data obtained using the open-source software CellProfiler (CP). Leukocytes and fluorescent bead images obtained using a Laser Scanning Cytometer were analyzed by CP and the results compared with those of conventional cytometric analyses' programs. Algorithms were developed enabling the analysis of leukocytes and beads by CP. CP provided similar results to those obtained by the cytometer software. Hallmark parameters, including cell count and fluorescence intensity, revealed a high correlation in the analysis of both programs. Therefore, CP is appropriate for cellular analysis on a self-assembled microscope, thereby enabling affordable cytometry.  相似文献   
17.
18.
We propose a navigational aid approach for the blind that relies on active optical profilometry with real-time electrotactile interfacing on the skin. Here we are concerned with the optical parts of this system. We point out the particular requirements the profilometer must meet to meet the needs of blind people. We show experimentally that an adequate compromise is possible that consists of a compact class I IR laser-diode triangulation profilometer with the following characteristics: 30-cm to 30-m range, 1-deg angular resolution, 20-ms acquisition time per measure of distance, 60° angular scanning field.  相似文献   
19.
Research using Internet surveys is an emerging field, yet research on the legitimacy of using Internet studies, particularly those targeting sensitive topics, remains under-investigated. The current study builds on the existing literature by exploring the demographic differences between Internet panel and RDD telephone survey samples, as well as differences in responses with regard to experiences of intimate partner violence perpetration and victimization, alcohol and substance use/abuse, PTSD symptomatology, and social support. Analyses indicated that after controlling for demographic differences, there were few differences between the samples in their disclosure of sensitive information, and that the online sample was more socially isolated than the phone sample. Results are discussed in terms of their implications for using Internet samples in research on sensitive topics.  相似文献   
20.
A DSS integrating empty and full containers transshipment operations is presented, addressing the typically unbalanced export/import containers trading problem. The problem is modeled as a network, where nodes represent customers, leasing companies, harbors and warehouses, while arcs represent transportation routes. The underlying mathematical model operates in stages, first prioritizing and adjusting full containers demands considering available empty containers supplies, and then statically optimizing costs. Transportation routes are registered and dynamically controlled, cyclically, for a given time horizon. The DSS is flexible, allowing several parameters to be configured. Experimental examples using randomly generated parameters were conducted to evaluate the effectiveness of the system.  相似文献   
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