Compression of Surface Texture Acceleration Signal Based on Spectrum Characteristics

Background: Adequate-data collection could enhance the realism of surface texture haptic online-rendering or offline-playback. A parallel challenge is how to reduce communication delays and improve storage space utilization. Methods: Based on the similarity of the short-term amplitude spectrumtrend, this paper proposes a frequency-domain compression method. A compression framework is designed, firstly to map the amplitude spectrum into a trend similarity grayscale image, compress it with the stillpicture-compression method, and then to adaptively encode the maximum amplitude and part of the initial phase of each time-window, achieving the final compression. Results: The comparison between the original signal and the recovered signal shows that when the time-frequency similarity is 90%, the average compression ratio of our method is 9.85% in the case of a single interact point. The subjective score for the similarity reached an excellent level, with an average score of 87.85. Conclusions: Our method can be used for offline compression of vibrotactile data. For the case of multi-interact points in space, the trend similarity grayscale image can be reused, and the compression ratio is further reduced

Natural Language Processing and Chinese ComputingThird CCF Conference, NLPCC 2014, Shenzhen, China, December 5-9, 2014. Proceedings /

XVIII, 474 p. 112 illus.online resource

The Influence of FY-4A High-Frequency LST Data on Data Assimilation in a Climate Model

Based on the Beijing Climate Center’s land surface model BCC_AVIM2.0, an ensemble Kalman filter (EnKF) algorithm is developed to assimilate the land surface temperature (LST) product of the first satellite of Fengyun-4 series meteorological satellites of China to study the influence of LST data with different time frequencies on the surface temperature data assimilations. The MODIS daytime and nighttime LST products derived from Terra and Aqua satellites are used as independent validation data to test the assimilation results. The results show that diurnal variation information in the FY-4A LST data has significant effect on the assimilation results. When the time frequencies of the assimilated FY-4A LST data are sufficient, the assimilation scheme can effectively reduce the errors and the assimilation results reflect more reasonable spatial and temporal distributions. The assimilation experiments with a 3 h time frequency show less bias as well as RMSEs and higher temporal correlations than that of the model simulations at both daytime and nighttime periods. As the temporal frequency of assimilated LST observations decreases, the assimilation effects gradually deteriorate. When diurnal variation information is not considered at all in the assimilation, the assimilation with 24 h time frequency showed the largest errors and smallest time correlations in all experiments. The results demonstrate the potential of assimilating high-frequency FY-4A LST data to improve the performance of the BCC_AVIM2.0 land surface model. Furthermore, this study indicates that the diurnal variation information is a necessary factor needed to be considered when assimilating the FY-4A LST

Molecular Characterization and Phylogenetic Analysis of Porcine Epidemic Diarrhea Viruses Associated with Outbreaks of Severe Diarrhea in Piglets in Jiangxi, China 2013

<div><p>Porcine epidemic diarrhea (PED), caused by porcine epidemic diarrhea virus (PEDV), is a highly contagious, acute enteric viral disease of swine characterized by vomiting, watery diarrhea, dehydration and death. To identify and characterize the field PEDVs associated with the outbreaks of severe diarrhea in piglets in Jiangxi, 2013, the complete genome sequences of two representative strains of PEDV, designated CH/JX-1/2013 and CH/JX-2/2013, were determined and analyzed. The genome sequences of both emergent Jiangxi PEDV strains, CH/JX-1/2013 and CH/JX-2/2013, were 28,038 nucleotides in length excluding 3’ poly (A) tail. Compared to the PEDV CV777 strain, CH/JX-1/2013 and CH/JX-2/2013 had some unique genetic characteristics in the proximal region of the 5´-UTRs. Phylogenetic analysis of the complete genomes and the structural proteins revealed that CH/JX-1/2013 and CH/JX-2/2013 had a close relationship with post-2010 Chinese PEDV strains and US strains identified in 2013. The nucleotide identity between the two Jiangxi strains (CH/JX-1/2013 and CH/JX-2/2013) and 30 strains of PEDV identified ante-2010 and post-2010 ranged from 96.3–97.0% and 97.3–99.7%, respectively. Multiple nucleotide and deduced amino acid mutations were observed in the ORF1a/b, S, ORF3, E, M and N genes among the current field PEDV strains when compared to the CV777 strain. Some of the mutations altered the amino acid charge and hydrophilicity, and notably, there was an amino acid substitution in the middle of one neutralizing epitope (L1371I) of the S gene of both CH/JX-1/2013 and CH/JX-2/2013. Taken together, the accumulated genetic variations of the current field PEDV strains might have led to antigenic changes of the viruses, which might confer the less effectiveness or failure of the CV777-based vaccines currently being widely used in Jiangxi, China.</p></div

Summary of the background information of CH/JX-1/2013, CH/JX-2/2013 and 33 reference strains used in this study.

<p>^a The accurate isolation year of LZC is unknown, but it is estimated to be before 2006 according to the GenBank submission date.</p><p>^b cell adapted PEDV strains.</p><p>Summary of the background information of CH/JX-1/2013, CH/JX-2/2013 and 33 reference strains used in this study.</p

Antigenic and hydrophilic analyses of the amino acid sequences of partial S protein of nine PEDV strains.

<p>Antigenic index was calculated by using Protean of DNAStar Lasergene under the Jameson-Wolf method. Hydrophilicity plot was constructed by Kyte-Doolittle method. The arrows indicate the discrepancy of antigenic and hydrophilic plots of partial S protein of PEDV strains between phylogenetic group 1 (CV777, LZC, SM98 and virulent DR13) and group 2 (CH/JX-1/2013, CH/JX-2/2013, BJ-2011-1, GD-B and IA1) PEDV strains. Panel A: antigenic analysis, and panel B: hydrophilic analysis.</p

Comparison of primary sequence of 5´-proximal region (nt 42–133) in 5´UTRs between CH/JX-1/2013, CH/JX-2/2013 and reference strains.

<p>The core sequences (CUAAAC) of leader transcription-regulating sequences (CS-L) are highlighted in gray, nucleotide insertions are highlighted in red, and mutations are highlighted in blue. The stem-loop 2 (SL 2) and stem-loop 4 (SL 4) are marked with braces. An ‘A’ deletion is seen in both CH/JX-1/2013 and CH/JX-2/2013 identified in this study and other strains excluding CV777 and LZC.</p

Phylogenetic trees based on the complete genome, aa sequences of structural proteins and ORF3 of PEDV strains.

<p>The trees were constructed by the distance-based neighbor-joining algorithm using MEGA 5.2.2 software. Bootstrap was set in 1,000 replicates with a value >70% to assess the significance of the tree topology. A bar of 0.002/0.005 indicates nucleotide or amino acid substitutions per site. “●” indicates the strains identified in this study, “○” indicates the strains from China, “◆” indicates the strains from Belgium, “■”indicates the strains from USA, “▲”indicates the strains from South Korea, “▼”indicates the strains from France, “◇”indicates the strains from Japan. 1A: Phylogenetic tree generated on the basis of nucleotide sequences of the complete genome of 33 PEDVs. 1B to 1F: Phylogenetic trees based on deduced amino acid sequences of S glycoprotein genes, ORF3, envelope, membrane, and nucleocapsid genes, respectively.</p

Nucleotide and amino acid mutations in ORF 3 of CH/JX-1/2013 and CH/JX-2/2013 when compared to PEDV CV777.

<p>^a Bold letters indicate the amino acids with changed charge.</p><p>Nucleotide and amino acid mutations in ORF 3 of CH/JX-1/2013 and CH/JX-2/2013 when compared to PEDV CV777.</p