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31.
This paper presents a fuzzy relational approach to human emotion recognition from facial expressions and its control. The proposed scheme uses external stimulus to excite specific emotions in human subjects whose facial expressions are analyzed by segmenting and localizing the individual frames into regions of interest. Selected facial features such as eye opening, mouth opening, and the length of eyebrow constriction are extracted from the localized regions, fuzzified, and mapped onto an emotion space by employing Mamdani-type relational models. A scheme for the validation of the system parameters is also presented. This paper also provides a fuzzy scheme for controlling the transition of emotion dynamics toward a desired state. Experimental results and computer simulations indicate that the proposed scheme for emotion recognition and control is simple and robust, with good accuracy.  相似文献   
32.
Experimentally the real and imaginary parts of the Fourier spectrum are separated and used to detect the nature of the object, i.e., whether the object is an odd or even function or a combination of both. A modified Twyman-Green setup is used for this purpose. This type of splitting of the object function into even and odd parts may become useful in different fields of image processing. As an application the same technique is used for accurate measurement of the grating frequency.  相似文献   
33.
Knowledge and Information Systems - Generalized spherical fuzzy number (GSFN) is an extension of spherical fuzzy number (SFN) which deals the uncertainties involved in the real-life problems in...  相似文献   
34.
Wireless Personal Communications - Compressive Sensing or Compressed sensing (CS) is a latest technique used for compression of medical signals and medical images which benefits both the speed and...  相似文献   
35.
Engineering with Computers - Plate structures are the integral parts of any maritime engineering platform. With the recent focus on composite structures, the need for optimizing their design and...  相似文献   
36.
Microsystem Technologies - Absorptive and dispersive properties of atmospheric hydrometeors, affect the propagation of millimetre-wave and submillimeter wave signals. In adverse weather condition,...  相似文献   
37.
The search for food stimulated by hunger is a common phenomenon in the animal world. Mimicking the concept, recently, an optimization algorithm Hunger Games Search (HGS) has been proposed for global optimization. On the other side, the Whale Optimization Algorithm (WOA) is a commonly utilized nature-inspired algorithm portrayed by a straightforward construction with easy parameters imitating the hunting behavior of humpback whales. However, due to minimum exploration of the search space, WOA has a high chance of trapping into local solutions, and more exploitation leads it towards premature convergence. The concept of hunger from HGS is merged with the food searching techniques of the whale to lessen the inherent drawbacks of WOA. Two weights of HGS are adaptively designed for every whale using the respective hunger level for balancing search strategies. Performance verification of the proposed hunger search-based whale optimization algorithm (HSWOA) is done by comparing it with 10 state-of-the-art algorithms, including three very recently developed algorithms on 30 classical benchmark functions. Comparison with some basic algorithms, recently modified algorithms, and WOA variants is performed using IEEE CEC 2019 function set. Statistical performance of the proposed algorithm is verified with Friedman's test, boxplot analysis, and Nemenyi multiple comparison test. The operating speed of the algorithm is determined and tested with complexity analysis and convergence analysis. Finally, seven real-world engineering problems are solved and compared with a list of metaheuristic algorithms. Numerical and statistical performance comparison with state-of-the-art algorithms confirms the efficacy of the newly designed algorithm.  相似文献   
38.
This article presents the practices of Australian and German financial service providers regarding the implementation of shop-floor control within different types of service systems. The results delivered in this article should serve as a guideline for future research to develop and adapt methods for shop-floor control in financial service systems. Interviews with 25 experts from the Australian and German financial services industry reveal novel insights into the practice of shop-floor control, suggesting that methods and concepts from manufacturing are only used to a limited extent for shop-floor control. Shop-floor control is mostly used to react quickly to unexpected deviations due to a low usage of forecasts and information systems. Thus, there seems to be improvement potential in the financial services industry in comparison with in the manufacturing industry in terms of shop-floor control. Further research within the production research area should use the empirical insights to test and adapt existing methods and to develop new ones, taking cultural differences into account.  相似文献   
39.
The presence of air boundary layer around a grinding wheel impedes the proper entry of cutting fluid into grinding zone and thereby lubrication and cooling are hampered. It leads to the thermal damage to the workpiece and rapid wheel wear. This experimental work is aimed at increasing the lubrication and cooling effects in grinding by a novel method of using scraper board. The experiments are conducted, using the scraper board, to find the critical region where the air pressure is zero. The coolant jet has then impinged into the grinding zone which is maintained within the critical region. The requirement of specific energy, surface texture, and mechanical properties of the ground surface are analyzed and compared with the traditional grinding and the grinding at various positions of scraper board. Results show that the grinding ratio improved by 35.6and 119%, surface roughness decreased by 36 and 54.2%, while the requirement of specific energy is reduced by 50.8 and 57.3% when scraper board is positioned at the critical distance in comparison to the 57.5° position and no scraper board, respectively. The results indicate that the introduction of fluid in the present method can improve the process efficiency and the product quality effectively.  相似文献   
40.
Individuals carrying cancer-predisposing germline mutations are known to be at a higher risk for cancers than those who do not carry them. This is also true of their biological relatives because they have a higher probability of being carriers of such mutant genes than unrelated individuals in the population. Further, there are now sufficient grounds for assuming that cancer-predisposed individuals may also be at a higher risk for cancers induced by ionizing radiation. In our earlier work, we examined the impact of this heterogeneity (with respect to cancer predisposition and radiosensitivity differentials) on risks of radiation-induced cancer at the population level. This paper is focused on the question of risks of radiation-induced cancer in relatives of cancer-predisposed individuals. Using an autosomal dominant model of cancer predisposition and radiosensitivity developed earlier and applying it to breast cancer risks associated with mutations in the BRCA1 gene, we show that: (1) The risk ratio (i.e. the ratio of risk of radiation-induced cancer in relatives to that in unrelated individuals) in the population increases with the degree of biological relatedness of the relative, being higher for close than for distant relatives; incomplete penetrance of the mutant gene "dilutes" this risk ratio. (2) The proportion of excess radiation-induced cancers in relatives (i.e. the attributable fraction) is higher than in unrelated individuals. (3) In relatives, the proportion of excess cancers due to radiosensitivity differentials alone depends on the strength of predisposition, the radiosensitivity differentials assumed, the radiation dose, the proportion of cancers due to predisposition, the mutant gene frequency and the penetrance of the mutant gene. This is in contrast to the situation for unrelated individuals, for whom the above-mentioned proportion is dependent on the first three but not on the last three of these factors. Further, even when the proportion of excess cancers is small, most of it is due to radiosensitivity differential alone both in unrelated individuals and in relatives. (4) For values of predisposition strength and radiosensitivity differential <10, even when the estimated frequency of a mutant BRCA1 gene is 0.0047 and the proportion of breast cancers due to these mutations is 38% (as is the case for Ashkenazi Jewish women under age 30), the increase in breast cancer risks is only marginal even for first-degree relatives. (5) These findings support the conclusion that increases in radiation risks to relatives (compared to those in unrelated individuals), to be detectable epidemiologically, will occur only when the mutant alleles are common and the strength of predisposition and radiosensitivity differentials are conjointly dramatic.  相似文献   
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