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81.
Individual digit-tip forces and moments during torque production on a mechanically fixed circular object were studied. During the experiments, subjects positioned each digit on a 6-dimensional force/moment sensor attached to a circular handle and produced a maximum voluntary torque on the handle. The torque direction and the orientation of the torque axis were varied. From this study, it is concluded that: (1) the maximum torque in the closing (clockwise) direction was larger than in the opening (counter clockwise) direction; (2) the thumb and little finger had the largest and the smallest share of both total normal force and total moment, respectively; (3) the sharing of total moment between individual digits was not affected by the orientation of the torque axis or by the torque direction, while the sharing of total normal force between the individual digit varied with torque direction; (4) the normal force safety margins were largest and smallest in the thumb and little finger, respectively.  相似文献   
82.
Xiong  Lizhi  Xia  Zhihua  Chen  Xianyi  Shim  Hiuk Jae 《Multimedia Tools and Applications》2019,78(21):30297-30313

Recently, cloud computing becomes a main platform for the distribution of multimedia content. The paradigm of multimedia distribution has been shifted from the models in traditional ways to the one in cloud computing. Security and privacy are two most important issues in multimedia distribution. The new model in cloud computing concerns the following issues. Firstly, outsourced content should be confidential except a data owner (DO). Secondly, the CSP is semi-trusted in the public cloud computing environment. A malicious data user (DU) may collude with the CSP to harm the DO’s rights and interests. Thirdly, the rights and interests of DU, including anonymity and unlinkability, should be protected. Based on the above problems, we propose and analyze a Multimedia Distribution based Re-encryption and Fingerprinting (MDRF) scheme in cloud computing. The proposed scheme 1) allows efficient distribution of the content while preserving security and privacy of copyright holders and end users, 2) resolve the problems of piracy tracing, collusion resistance, and dispute resolution, and 3) protect the rights and interests of DU, including anonymity and unlinkability. The analysis part demonstrates that the security of DO and DU are well provided in the proposed scheme. The experimental results evaluate the performance of our framework in terms of collusion resistance of the fingerprint and imperceptibility of fingerprint embedding.

  相似文献   
83.
Pressure fluctuations in a three phase bubble column reactor operating at relatively low pressure (92 KPa) have been analyzed by adopting the spectral and fractal analyses to get the engineering informations for the on-line control and fault diagnosis of the reactors. The mean value, standard deviation, skewness and kurtosis of the pressure fluctuations have been obtained. The local fractal dimension has been determined from the Pox diagram obtained by means of the rescaled range analysis of the pressure fluctuations based on the fractional Brownian motion. The local fractal dimension of pressure fluctuations has increased and thus the pressure fluctuation signals have become less persistent and irregular, with increases in the gas flow rate reaction temperature, particle size and solid content in the slurry phase. The local fractal dimension has been well correlated in terms of the operating variables.  相似文献   
84.
The plastic-collapse load and post-collapse behaviour of ductile, thin-walled tubes compressed between cylindrical indenters are analyzed for a complete range of indenter radii; experiments on steel, brass and aluminium alloy tubes show the usefulness of this analysis when deflections are large. The effect of shear force is considered; shear can develop when the sides of the tube are constrained against lateral expansion. While crushing by diametrically opposed indenters results in symmetrical modes of deformation, any shear in addition to the normally applied forces results in an asymmetrical mode of deformation which is more compliant than the symmetrical mode. The asymmetrical mode of deformation is initially unstable.  相似文献   
85.
Choe JH  Jang A  Lee ES  Choi JH  Choi YS  Han DJ  Kim HY  Lee MA  Shim SY  Kim CJ 《Meat science》2011,87(1):12-18
This study aimed to evaluate the oxidative and color stability of cooked ground pork containing lotus leaf powder at 0.1 (LP1) and 0.5% (LP2) as well as barley leaf powder at 0.1 (BP1) and 0.5% (BP2) during refrigerated storage for 10 days. The oxidative stability of these powders was compared with butylhydroxytoluene (BHT). LP1 had higher a* and lower b* values than the control (-) over 4 days (p<0.05). The pH values of the ground pork samples made with addition of LP and BHT decreased until day 4 and then increased. Thiobarbituric acid-reactive substance (TBARS) values were lowest in LP2 on day 10 (p<0.05). The ground pork samples containing LP and BP had lower peroxide values (POVs) and conjugated dienes (CD) compared to the control (-).These results indicate that LP or BP can be incorporated into ground pork to effectively retard oxidation after cooking.  相似文献   
86.
Abstract

Different microstructures having acicular ferrite as the major phase but with various types and amounts of microphases were obtained by applying different cooling processes to C–Mn steels containing fine non-metallic inclusions. Optical and electron microscopy were carried out to identify the various microphases in the acicular ferrite microstructure, and their mechanical properties were measured and compared to study the effect of the microphases on the microstructure–properties relationship in C–Mn wrought steels. The existence and increase of the fraction of small isolated martensite between the acicular ferrite laths were found to play an important role in determining the tensile strength and low temperature impact toughness of the steels. However, the elongation and room temperature impact toughness were rather insensitive to the microphases. This may be attributed to the uniform distribution and isolation of relatively small martensite due to the fine interlocking character of the acicular ferrite microstructure.  相似文献   
87.
Wave field synthesis (WFS) has been gathering more and more attention recently due to its ability to perfectly reproduce an original sound field. However, to realize theoretically perfect WFS, a four‐sided loudspeaker array that encloses the listener is required. However, it is difficult to build such a system except in large listening spaces, such as a theater or concert hall. In other words, if the listening space is a home, installing a side loudspeaker array is impractical. If the two side walls located to the left and right of the listener can be omitted, a setup using only front and rear loudspeaker arrays may be a solution. In this letter, we present a subjective listening experiment of sound localization/distance based on a WFS using a front and rear loudspeaker array system which is conducted on two listening points and shows average localization errors of 6.1° and 9.18°, while the average distance errors are –27% (0.5 m) and –29% (0.6 m), respectively.  相似文献   
88.
Ankylosing spondylitis (AS) results in disease-specific inflammation at the site of ligamentous insertion into the bone. Atlantoaxial joint subluxation and vertical subluxation of the axis may occur as a consequence of instability resulting from the inflammatory process. Spontaneous anterior atlantoaxial subluxation is a well recognized complication in about 2% of patients with AS, and presents with or without signs of spinal cord compression. Vertical subluxation may follow anterior or posterior subluxation. It was noted in 3-8% of patients with rheumatoid arthritis, but is an exceedingly rare complication of AS. Moreover, it has never been reported that multiple cerebellar infarction and bulbar symptoms developed spontaneously due to atlanto-occipital subluxation and vertical subluxation in a patient with a long [corrected] history of AS. We describe a man with AS who developed multiple cerebellar infarction due to vertebral artery obstruction and bulbar symptoms associated with atlanto-occipital subluxation and vertical subluxation.  相似文献   
89.

Recently, pedestrian detection systems have become an important technology in the development of the advanced driver assistance system (ADAS) for the autonomous car. The histogram of oriented gradients (HOG) is currently the most basic algorithm for detecting pedestrians, but it treats the entire body of the pedestrian as one single feature. In other words, if the entire body of the pedestrian is not visible, the detection rate under HOG decreases markedly. To solve this problem, we propose a detection system using a deformable part model (DPM) that divides the pedestrian data into two parts using a latent support vector machine (SVM)-based machine-learning technique. Experimental results show that our approach achieves better performance in a detection system than the existing method. In practice, there are many occlusions in the environment in front of the vehicle. For example, the surrounding transport facilities, such as a car or another obstacle, can occlude a pedestrian. These occlusions can increase the false detection rate and cause difficulties during the detection process. Our proposed method uses a different approach and can easily be applied in real-world scenarios, regardless of occlusions.

  相似文献   
90.
We demonstrate a gain-clamped semiconductor optical amplifier (GC-SOA) which has gratings under both end regions of an active waveguide. Two gratings of the new GC-SOA are fabricated in different lengths. Their lasing modes and gain characteristics are measured and analyzed with different combinations of grating lengths. It shows different gain and noise characteristics according to the measurement direction in asymmetric grating combinations.  相似文献   
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