37,286 research outputs found
Chinese and North American Culture: a New Perspective in Linguistics Studies
We explored the two cultures in the two countries. There has been discussed on Chinese culture and North American culture. Chinese language, ceramics, architecture, music, dance, literature, martial arts, cuisine, visual arts, philosophy, business etiquette, religion, politics, and history have global influence, while its traditions and festivals are also celebrated, instilled, and practiced by people around the world. The culture of North America refers to the arts and other manifestations of human activities and achievements from the continent of North America. The American way of life or simply the American way is the unique lifestyle of the people of the United States of America. It refers to a nationalist ethos that adheres to the principle of life, liberty and the pursuit of happiness
A novel fast fractal image compression method based on distance clustering in high dimensional sphere surface
Fractal encoding method becomes an effective image compression method because of its high compression ratio and short decompressing time. But one problem of known fractal compression method is its high computational complexity and consequent long compressing time. To address this issue, in this paper, distance clustering in high dimensional sphere surface is applied to speed up the fractal compression method. Firstly, as a preprocessing strategy, an image is divided into blocks, which are mapped on high dimensional sphere surface. Secondly, a novel image matching method is presented based on distance clustering on high dimensional sphere surface. Then, the correctness and effectiveness properties of the mentioned method are analyzed. Finally, experimental results validate the positive performance gain of the method
Behavior modelling and individual recognition of sonar transmitter for secure communication in UASNs
It is necessary to improve the safety of the underwater acoustic sensor networks (UASNs) since it is mostly used in the military industry. Specific emitter identification is the process of identifying different transmitters based on the radio frequency fingerprint extracted from the received signal. The sonar transmitter is a typical low-frequency radiation source and is an important part of the UASNs. Class D Power Amplifier, a typical non-linear amplifier, is usually used in sonar transmitters. The inherent nonlinearity of
power amplifiers provides fingerprint features that can be distinguished without transmitters for specific emitter recognition. Firstly, the non-linearity of the sonar transmitter is studied in depth, and the nonlinearity of the power amplifier is modeled and its non-linearity characteristics are analyzed. After obtaining the nonlinear model of an amplifier, a similar amplifier in practical application is obtained by changing its model parameters as the research object. The output signals are collected by giving the same input of different models, and then the output signals are extracted and classified. In this paper, the memory polynomial model is used to model the amplifier. The power spectrum features of the output signals are extracted as fingerprint features. Then the dimensionality of the high-dimensional features is reduced. Finally, the classifier is used to recognize the amplifier. The experimental results show that the individual sonar transmitter can be well identified by using the non-linear characteristics of the signal. By this way, this method can enhance the communication safety of UASNs
Efficient identity-based broadcast encryption without random oracles.
We propose a new efficient identity-based broadcast encryption scheme without random oracles and prove that it achieves selective identity, chosen plaintext security. Our scheme is constructed based on bilinear Diffie-Hellman inversion assumption and it is a good efficient hybrid encryption scheme, which achieves O(1)-size ciphertexts, public parameters and constant size private keys. In our scheme, either ciphertexts or public parameters has no relation with the number of receivers, moreover, both the encryption and decryption only require one pairing computation. Compared with other identity-based broadcast encryption schemes, our scheme has comparable properties, but with a better efficiency
Editorial: Security of cloud service for the manufacturing industry
With the rapid development of the industrial Internet, cloud service-based manufacturing has emerged as a next generation manufacturing paradigm that has potential to revolutionize the manufacturing industry. It is foreseeable that cloud services will be popular in the next generation manufacturing industry. In recent years, more and more manufacturing companies have recognized the benefits of cloud service and have developed cloud-based manufacturing models. However, the security problems need to be researched and solved for the cloud services in the manufacturing industry, especially the data security issues are important, and restrict the cloud application in the manufacturing industry. Regarding the security of data, some people believe that when data are stored in the cloud, manufacturing companies lose control of the data. The manufacturing companies focus on how to secure the data from the top-level management and how to minimize the security risks, such as those caused by data security or service migration challenges. The manufacturing companies select the reliable cloud service while consider function and budget feasibility. How to ensure security in cloud service for the manufacturing industry has become a topic of increasing interest for both academic researchers and developers from the industry. This special issue addresses this emerging and fast developing research area on cloud security in manufacturing industry. The summary of these papers is as follows. [...
Reliability analysis of an air traffic network: from network structure to transport function
To scientifically evaluate the reliability of air traffic networks, a definition of air traffic network reliability is proposed in this paper. Calculation models of the connectivity reliability, travel-time reliability, and capacity reliability of the air traffic network are constructed based on collected historical data, considering the current status and the predicted future evolution trends. Considering the randomness and fuzziness of factors affecting reliability, a comprehensive evaluation model of air traffic networks based on the uncertainty transformation model is established. Finally, the reliability of the US air traffic network is analyzed based on data published by the Transportation Statistics Bureau of the US Department of Transportation. The results show that the connectivity reliability is 0.4073, the capacity reliability is 0.8300, the travel-time reliability is 0.9180, and the overall reliability evaluated is “relatively reliable”. This indicates that although the US structural reliability is relatively low, the US air traffic management is very efficient, and the overall reliability is strong. The reliability in nonpeak hours is much higher than that in peak hours. The method can identify air traffic network reliability efficiently. The main factors affecting reliability can be found in the calculation process, and are beneficial for air traffic planning and management. The empirical analysis also reflects that the evaluation model based on the uncertainty transformation model can transform the quantitative data of network structure and traffic function into the qualitative language of reliability
Time Quantified Monte Carlo Algorithm for Interacting Spin Array Micromagnetic Dynamics
In this paper, we reexamine the validity of using time quantified Monte Carlo
(TQMC) method [Phys. Rev. Lett. 84, 163 (2000); Phys. Rev. Lett. 96, 067208
(2006)] in simulating the stochastic dynamics of interacting magnetic
nanoparticles. The Fokker-Planck coefficients corresponding to both TQMC and
Langevin dynamical equation (Landau-Lifshitz-Gilbert, LLG) are derived and
compared in the presence of interparticle interactions. The time quantification
factor is obtained and justified. Numerical verification is shown by using TQMC
and Langevin methods in analyzing spin-wave dispersion in a linear array of
magnetic nanoparticles.Comment: Accepted for publication in Phys. Rev.
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