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11.
GripSee: A Gesture-Controlled Robot for Object Perception and Manipulation   总被引:3,自引:0,他引:3  
We have designed a research platform for a perceptually guided robot, which also serves as a demonstrator for a coming generation of service robots. In order to operate semi-autonomously, these require a capacity for learning about their environment and tasks, and will have to interact directly with their human operators. Thus, they must be supplied with skills in the fields of human-computer interaction, vision, and manipulation. GripSee is able to autonomously grasp and manipulate objects on a table in front of it. The choice of object, the grip to be used, and the desired final position are indicated by an operator using hand gestures. Grasping is performed similar to human behavior: the object is first fixated, then its form, size, orientation, and position are determined, a grip is planned, and finally the object is grasped, moved to a new position, and released. As a final example for useful autonomous behavior we show how the calibration of the robot's image-to-world coordinate transform can be learned from experience, thus making detailed and unstable calibration of this important subsystem superfluous. The integration concepts developed at our institute have led to a flexible library of robot skills that can be easily recombined for a variety of useful behaviors.  相似文献   
12.
Disposal of worn tires poses a major problem worldwide. In Greece more than 50,000 tons of worn automobile tires are stockpiled annually. This paper presents the results of laboratory research that examines the incorporation of tire rubber granules as a partial replacement for the sand in cement mortars. Physical and mechanical properties of these rubber mixtures are studied while, for the first time, resistance to chloride ion penetration is measured.Results showed a decrease in mechanical properties, whereas an increase in chloride ion penetration resistance has been observed. This implies that cement-based mortar and concrete products, modified with tire rubber granules as a partial replacement for the sand, can be used in applications where mechanical properties are not of prime importance but where high resistance to chloride ion penetration is demanded.  相似文献   
13.
Evaluation of shelf life was made of cured, cooked, sliced turkey breast fillets and a type of cooked pork sausage called 'piroski', stored in vacuum and in six different modified atmospheres (MA) at +4 and +10?°C. Total viable count, lactic acid bacteria, pH changes, colour attributes and the presence of pathogenic bacteria (listeriae, staphylococci) were monitored during the storage. The results of the study showed that the average shelf life for both products was 2 and 1 week at 4 and 10?°C, respectively. By the end of these periods, the bacterial population consisting of only lactic acid bacteria reached 10(8) cfu g(-1). Macroscopical (colour, drip loss and slime) and organoleptical changes (sour odours) were not related to pH and observed already at pH values >5.5. It is concluded that the use of MA packaging in these tests did not extend and not reduce the product shelf life in comparison to vacuum packaging.  相似文献   
14.
Peroxisome proliferator-activated receptors (PPAR) are nuclear hormone receptors that control the expression of genes involved in lipid homeostasis in mammals. We searched for PPAR in sea bass, a marine fish of particular interest to aquaculture, after hypothesizing that the physiological and molecular processes that regulate lipid metabolism in fish are similar to those in mammals. Here, we report the identification of complementary DNA and corresponding genomic sequences that encode three distinct PPAR from sea bass. The sea bass PPAR are the structural homologs of the mammalian PPARα, β/δ and γ isotypes. As revealed by RNase protection, the tissue expression profile of the fish PPAR appears to be very similar to that of the mammalian PPAR homologs. Thus, PPARα is mainly expressed in the liver, PPARγ in adipose tissue, and PPARβ in all tissues tested, with its highest levels in the liver, where it is also the dominant isotype expressed. Like mammalian PPAR, the sea bass isotypes recognize and bind to PPAR response elements of both mammalian and piscine origin, as heterodimers with the 9-cis retinoic acid receptor. Through the coactivator-dependent receptor ligand assay, we also demonstrated that natural FA and synthetic hypolipidemic compounds can act as ligands of the sea bass PPARα and β isotypes. This suggests that the sea bass PPAR act through similar mechanisms and perform the same critical lipid metabolism functions as mammalian PPAR.  相似文献   
15.
Mass customization systems aim to receive customer preferences in order to facilitate personalization of products and services. Current online configuration systems are unable to efficiently identify real customer affective needs because they offer an excess variety of products that usually confuse customers. On the other hand, mining affective customer needs may result in recommender systems, which can enhance existing configuration systems by recommending initial configurations according to customer affective needs. This paper introduces a mass customization recommender system that exploits data mining techniques on automotive industry customer data aiming at revealing associations between user affective needs and the design parameters of automotive products. One key novelty of the presented approach is that it deploys the Citarasa engineering, a methodology that focuses on the provision of the appropriate characterizations on customer data in order to associate them with customer affective needs. Based on the application of classification techniques we build a recommendation engine, which is evaluated in terms of user satisfaction, tool’s effectiveness, usefulness and reliability among other parameters.  相似文献   
16.
A strong separation of concerns is necessary in order to make the design of domain‐specific functional components independent from cross‐cutting concerns, such as concurrent access to the shared resources of the execution platform. Native coordination mechanisms, such as locks and monitors, allow developers to address these issues. However, such solutions are not modular; they are complex to design, debug, and maintain. We present the JavaBIP framework that allows developers to think on a higher level of abstraction and clearly separate the functional and coordination aspects of the system behavior. It implements the principles of the Behavior, Interaction, and Priority (BIP) component framework rooted in rigorous operational semantics. It allows the coordination of existing concurrent software components in an exogenous manner, relying exclusively on annotations, component APIs, and external specification files. We introduce the annotation and specification syntax of JavaBIP and illustrate its use on realistic examples, present the architecture of our implementation, which is modular and easily extensible, and provide and discuss performance evaluation results. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
17.
This paper describes the numerical evaluation of a novel cross flow tube bundle heat exchanger that combines tubes of different diameter in an inline arrangement for the purpose of reducing gas side particulate fouling rates while preserving acceptable levels of heat transfer and pressure drop performance. Three arrangements are compared: a common inline tube bundle heat exchanger with cylinders of equal diameter and two other arrangements that consist of alternately placed cylinders with a diameter ratio of d/D = 0.5, at two different transverse spacings. Numerical calculations are performed in order to study heat transfer, pressure drop and fouling rates from flue gases with suspended ash particles. The alternating tube sizes achieve a suppression of the vortex shedding mechanism that has previously been shown to enhance downstream particle deposition. Results show that, compared to the standard arrangement, the tube bundle with unequal cylinders placed at the largest transverse spacing achieves a significant (~30%) reduction in particle deposition rate without sacrificing acceptable values of heat transfer per unit volume and low pressure drop.  相似文献   
18.
Uremic polyneuropathy is one of the major complications of long‐term end‐stage renal disease. In the present study, we performed an electrophysiologic evaluation in 17 patients having a mean age of 49 ± 11 years. The patients were divided into two groups according to dialysis method. Group A included 9 patients who were undergoing conventional hemodialysis (mean age, 44.2 ± 12.5 years; mean duration on dialysis, 21.7 ± 4.3 months); group B included 8 patients undergoing hemofiltration (mean age, 55.2 ± 5.2 years; mean duration on treatment, 27 ± 7.6 months). Measurements of the distal latency time of the sensory fibers (median, ulnar, and sural nerves), and measurements of the distal latency time and peripheral conduction velocity of the motor fibers (median and peroneal nerves) were performed. In addition, we recorded somatosensory evoked potentials after peripheral stimulation of the median and peroneal nerves. The electrophysiologic evaluations were repeated two times at intervals of 12 months. In group A, a statistically significant worsening of motor and sensory conductance in the upper and lower limbs was observed; in group B, a statistically significant improvement was found. These findings suggest that hemofiltration has a more beneficial effect on motor and sensory conductivity than does conventional hemodialysis.  相似文献   
19.
20.
Cryptosporidiumparvum is a clinically important eukaryotic parasite that causes the disease cryptosporidiosis, which manifests with gastroenteritis-like symptoms. The protist has mitosomes, which are organelles of mitochondrial origin that have only been partially characterized. The genome encodes a highly reduced set of transport proteins of the SLC25 mitochondrial carrier family of unknown function. Here, we have studied the transport properties of one member of the C. parvum carrier family, demonstrating that it resembles the mitochondrial ADP/ATP carrier of eukaryotes. However, this carrier has a broader substrate specificity for nucleotides, transporting adenosine, thymidine, and uridine di- and triphosphates in contrast to its mitochondrial orthologues, which have a strict substrate specificity for ADP and ATP. Inspection of the putative translocation pathway highlights a cysteine residue, which is a serine in mitochondrial ADP/ATP carriers. When the serine residue is replaced by cysteine or larger hydrophobic residues in the yeast mitochondrial ADP/ATP carrier, the substrate specificity becomes broad, showing that this residue is important for nucleotide base selectivity in ADP/ATP carriers.  相似文献   
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