|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Attribute-Based Access Control for Multi-Authority Systems with Constant Size Ciphertext in Cloud Computing显示文摘In most existing CP-ABE schemes, there is only one authority in the system and all the public keys and private keys are issued by this authority, which incurs ciphertext size and computation costs in the encryption and decryption operations that depend at least linearly on the number of attributes involved in the access policy. We propose an efficient multi-authority CP-ABE scheme in which the authorities need not interact to generate public information during the system initialization phase. Our scheme has constant ciphertext length and a constant number of pairing computations. Our scheme can be proven CPA-secure in random oracle model under the decision q-BDHE assumption. When user's attributes revocation occurs, the scheme transfers most re-encryption work to the cloud service provider, reducing the data owner's computational cost on the premise of security. Finally the analysis and simulation result show that the schemes proposed in this thesis ensure the privacy and secure access of sensitive data stored in the cloud server, and be able to cope with the dynamic changes of users' access privileges in large-scale systems. Besides, the multi-authority ABE eliminates the key escrow problem, achieves the length of ciphertext optimization and enhances the effi ciency of the encryption and decryption operations. | CHEN Yanli SONG Lingling YANG Geng | 2016 | China Communications2016,13,2: | 15 |
| 2 | Intent Pattern Recognition of Lower-limb Motion Based on Mechanical Sensors显示文摘Based on the regularity nature of lower-limb motion,an intent pattern recognition approach for above-knee prosthesis is proposed in this paper. To remedy the defects of recognizer based on electromyogram(EMG), we develop a pure mechanical sensor architecture for intent pattern recognition of lower-limb motion. The sensor system is composed of an accelerometer, a gyroscope mounted on the prosthetic socket, and two pressure sensors mounted under the sole. To compensate the delay in the control of prosthesis, the signals in the stance phase are used to predict the terrain and speed in the swing phase. Specifically, the intent pattern recognizer utilizes intraclass correlation coefficient(ICC) according to the Cartesian product of walking speed and terrain. Moreover, the sensor data are fused via DempsterShafer's theory. And hidden Markov model(HMM) is used to recognize the realtime motion state with the reference of the prior step. The proposed method can infer the prosthesis user's intent of walking on different terrain, which includes level ground,stair ascent, stair descent, up and down ramp. The experiments demonstrate that the intent pattern recognizer is capable of identifying five typical terrain-modes with the rate of 95.8%. The outcome of this investigation is expected to substantially improve the control performance of powered above-knee prosthesis. | Zuojun Liu Wei Lin Yanli Geng Peng Yang | 2017 | IEEE/CAA Journal of Automatica Sinica2017,4,4: | 15 |
| 3 | Expression of CDC42 in cervical squamous cell carcinoma and its correlation with clinicopathologic characteristics显示文摘Objective:The high expression of cell division cycle 42 protein(CDC42)may be involved in the occurrence and progression of several tumors.However,the expression and function of CDC42 in cervical squamous cell carcinoma remains unclear.This study aimed to investigate the expression of CDC42 in cervical squamous cell carcinoma and its correlation with clinicopathologic characteristics.Methods:The expression of CDC42 in 162 cervical squamous cell carcinoma tissue samples and 33 normal cervical tissue samples was investigated by immunohistochemistry.The CDC42 mRNA expression was detected by reverse transcription-polymerase chain reaction(RT-PCR).Results:ThecervicalsquamouscellcarcinomagroupshowedasignificantlyhigherCDC42positiverate,compared to the normal cervical tissues(P<0.05).Furthermore,the tissues of stage II-IV carcinoma patients showed higher CDC42 expression levels compared to stage I patients(P=0.05).In addition,the expression of CDC42 was not correlated to age of patients,differentiation degree of cancer cells,or lymph node metastasis(P>0.05).Furthermore,compare with normal cervical tissues,the CDC42 mRNAexpressionincervicalcancerhadnosignificantdifference.Conclusions:CDC42 was up-regulated at protein level,but not mRNA level,in cervical squamous cell carcinoma.The high expression of CDC42 was correlated to the clinical stage of the patients,indicating that CDC42 might contribute to the progression of cervical squamous cell carcinoma. | Ding Ma Yuan Cheng Youyi Zhang Yanli Guo Zijian Li Geng Li | 2013 | Chinese Journal of Cancer Research2013,25,6: | 3 |
| 4 | Seasonal differences in sources and formation processes of PM2.5 nitrate in an urban environment of North China显示文摘Nitrate(NO_(3)^(−))has been the dominant ion of secondary inorganic aerosols(SIAs)in PM_(2.5) in North China.Tracking the formation mechanisms and sources of particulate nitrate are vital to mitigate air pollution.In this study,PM_(2.5) samples in winter(January 2020)and in summer(June 2020)were collected in Jiaozuo,China,andwater-soluble ions and(δ_(15)N,δ_(18)O)-NO_(3)^(−)were analyzed.The results showed that the increase of NO_(3)^(−)concentrations was the most remarkable with increasing PM_(2.5) pollution level.δ_(18)O-NO_(3)^(−)values for winter samples(82.7‰ to 103.9‰)were close to calculated δ_(18)O-HNO_(3)(103‰±0.8‰)values by N_(2)O_(5) pathway,while δ_(18)O-NO_(3)^(−)values(67.8‰ to 85.7‰)for summer samples were close to calculated δ_(18)O-HNO_(3) values(61‰±0.8‰)by OH oxidation pathway,suggesting that PM_(2.5) nitrate is largely from N_(2)O_(5) pathway inwinter,while is largely from OH pathway in summer.Averaged fractional contributions of P_(N2O5+H2O) were 70% and 39% in winter and summer sampling periods,respectively,those of POH were 30% and 61%,respectively.Higher δ_(15)N-NO_(3)−values for winter samples(3.0‰to 14.4‰)than those for summer samples(-3.7‰to 8.6‰)might be due to more contributions from coal combustion in winter.Coal combustion(31%±9%,25%±9%in winter and summer,respectively)and biomass burning(30%±12%,36%±12%in winter and summer,respectively)were the main sources using Bayesian mixing model.These results provided clear evidence of particulate nitrate formation and sources under different PM_(2.5) levels,and aided in reducing atmospheric nitrate in urban environments. | Yanli Li Yaping Geng Xiaomian Hu Xijie Yin | 2022 | Journal of Environmental Sciences2022,34,10: | 2 |
| 5 | EBS-Based Collusion Resistant Group Key Management Using Attribute-Based Enc ryption显示文摘The major advantages of EBS-based key management scheme are its enhanced network survivability, high dynamic performance, and better support for network expansion. But it suffers from the collusion problem, which means it is prone to the cooperative attack of evicted members. A novel EBS-based collusion resistant group management scheme utilizing the construction of Ciphertext-Policy Attribute-Based Encryption (CP-ABE) is proposed. The new scheme satisfies the desired security properties, such as forward secrecy, backward secrecy and collusion secrecy. Compared with existing EBS-based key management scheme, the new scheme can resolve EBS collusion problem completely. Even all evicted members work together, and share their individual piece of information, they could not access to the new group key. In addition, our scheme is more efficient in terms of communication and computation overhead when the group size is large. It can be well controlled even in the case of large-scale application scenarios. | Chen Yanli Yang Geng | 2012 | China Communications2012,9,1: | 1 |
| 6 | A high-power and high-efficiency mini generator for scavenging energy from human foot movement显示文摘Harvesting energy from human movement and converting it into electricity is a promising method to address the issue of sustainable power supply for wearable electronic devices.Using traditional energy harvesters for practical applications is difficult due to their low output power.In this paper,an energy harvester with high power and efficiency is reported based on the principle of electromagnetic induction.It adopts a tiny compound mechanism comprising symmetrical lever-sector gear,which can amplify the vertical displacement of the human heel of 1.44 times without affecting the flexibility and comfort of human movement.The lever-sector gear and gear acceleration mechanism can achieve high output power from the tiny vertical movements of the heel.The results demonstrated that the average power and energy harvesting efficiency of the device are 1 W and 63%,respectively.Moreover,combining a novel controllable electric switch and energy management circuit allows the energy harvester to be worn by individuals with different weights and functions as a continuous real-time power supply for various electronic devices(mobile phones,smartwatches,etc.).Therefore,this research provides a new approach for the highly efficient harvesting of human motion energy and sustainable power supply of wearable electronics. | WU Hui QIAN Shuo HOU XiaoJuan ZHAO JuanHong ZHANG Jie SONG XiaoGuang LIU YanLi SHI ShuZheng GENG WenPing MU JiLiang HE Jian CHOU XiuJian | 2023 | Science China(Technological Sciences)2023,66,12: | 0 |