The increasing applications of 3D point clouds require efficient compression techniques to achieve high-quality and low-delay services. However, the computational efficiency and rate-distortion ...performance for large-scale dense point clouds are still challenging, and the phenomenon of reconstruction ability degradation also exists when the network is deep. To solve these challenges, we propose a novel fully end-to-end point cloud compression model based on sparse convolution. Specifically, we adopt a long-range-residual aided architecture to avoid the reconstruction degradation and high computational complexity of deep networks. Further, we propose a multi-scale geometry compression module to construct an end-to-end network that avoids the accumulation of reconstruction distortion during decoding. Experiments on the large-scale Moving Picture Experts Group (MPEG) PCC benchmarks show that our model outperforms the latest Video-based Point Cloud Compression (V-PCC) scheme in terms of lossy geometry compression by 50.4% in D1 BD-rate and 50.8% in D2 BD-rate, while maintaining affordable processing speed and memory consumption.
This paper tries the first attempt in GNSS related fields, the signal emitted by four different static navigation satellites on the ground, passed the latest self-research four-channel navigation ...satellite link emulator, which emulating the relative motion between the satellite and the user, and adding signal transmission channel time-varying parameters (group delay, phase shift, Doppler, fading), finally, the navigation receiver receives signal to complete positioning. Essence of satellite navigation and positioning is aligning the satellite and user time, and measuring signal transmission delay. This paper has established the positioning principle model based on four-channel satellite link emulator, designed the positioning implementation process, analyzed the errors generated model, proposed a delay parameters leading simulation control method. The measured results show that it could effectively reduce the positioning error caused by the navigation satellite channel emulator. It provides an effective way to fully verify its signal performance indicators, before the navigation satellite launched.
Study on isolation and identification of Aspergillus oryzae from bovine rumen and analysis of its effect on corn straw degradation Wang Ping, Henan Agricultural University,Zhengzhou(China), Engineering College of Animal Husbandry and Veterinary Science; Wang Pengpeng, Henan Agricultural University,Zhengzhou(China), Engineering College of Animal Husbandry and Veterinary Science; Zuo Ruiyu, Henan Agricultural University,Zhengzhou(China), Engineering College of Animal Husbandry and Veterinary Science
Henan nongye daxue xuebao,
May. 2010, Letnik:
44, Številka:
3
Journal Article
为提高玉米秸秆中纤维素的降解率,从牛瘤胃内容物中筛选出高效的纤维素降解菌,并研究该菌对玉米秸秆的发酵效果.经选择性培养基初筛和固体发酵培养复筛,筛选出1株纤维素酶活性相对较高的菌株（No.3）,经形态特征观察和26S rDNAITS区序列分析确定其为米曲霉（Aspergillus ...oryzae）.对其酶学特性及发酵效果进行了研究.结果表明,该菌所产纤维素酶的最适pH值为5.5~6.0,最适温度为50℃.其羧甲基纤维素酶活性和滤纸糖酶活性分别达到6.01,1.15 U.g-1.与发酵前相比,发酵后的玉米秸秆中还原糖和可溶性蛋白含量分别提高123.53%,48.98%（P〈0.05）;纤维素和半纤维素的降解率分别为25.01%,45.99%（P〈0.05）.说明该菌株具有较高的应用价值,可以作为开发和利用农作物秸秆的优良菌株.著者文摘
In order to increase cellulose degradation of corn straw by microorganisms,the aim of this study was to isolate cellulose-degrading microorganism from bovine rumen and analyse its effect on straw utilization.The microorganism was first screened in selective culture medium for cellulase detection,and then cultured in corn straw medium.One superior cellulose decomposing strain（No.3） was isolated from bovine rumen and identified as Aspergillus oryzae by morphological and 26S rDNA technique,which was used for solid fermentation of corn straw to determine cellulase characteristics and fermentation results.The results showed that the optimum pH and
The paper presents the application of the gas path electrostatic monitoring technology for monitoring of carbon deposition in combustion chamber of a turbojet engine. In order to obtain the accurate ...charge signal, the Least Mean Square (LMS) fitting method is adopted in electrostatic monitoring signal calculus. By the comparison of the data from the 101 st and 13 0th stage, we observer the active level of the signal from the 13 0th stage is significantly higher than that from the 101 st stage, but no evident difference can be detected in the positive (negative) event rate. The change in the active level of the signal can be contributed to the carbon depositions in combustion chamber found in the disassembly of the engine after the 13 0th stage test. So, we can conclude that the electrostatic monitoring system can detect the carbon depositions in the combustion chamber of a turbojet engine.
Protein resources are severely short around the world, especially for the requirement of animal production. How to solve this problem has become more and more important. The production of ...high-quality protein stuffs from the low-quality unconventional protein resources by microbial fermentation is the main research direction all over the world. In this study, the low-quality protein stuffs such as cottonseed, blood and feather meals were fermented by Aspergillus oryzae (A. oryzae), which was isolated from bovine rumen and identified by 26S rDNA. The orthogonal experiment and single factor analysis of variance method was used to select the optimal fermentation nutrient media and conditions. The results showed that the optimum medium compositions of raw materials for replacing soybean meal were 30% blood meal, 26% cottonseed meal, 4% feather meal, 35% wheat bran, 5% corn flour; the best fermentation conditions were initial pH 6, 40% moisture, 2% fungal inoculation volume, and 60 h fermentation. Under the best conditions of solid-state fermentation (SSF), the soluble protein content, amino nitrogen content, crude protein content, free amino acids in the fermented products were 173.72 mg/g, 34.75 mg/g, 48.97%, 100.95 mg/g, which were increased by 82.68%, 379.97%, 12.91%, 570.00%, compared with the unfermented product, respectively (P<;0.05). The activities of protease, amylase and cellulase in the fermented products were 2341.83 U/g, 36780.8 U/g and 6835.43 U/g, respectively. It can be concluded that the unconventional protein resources can be significantly improved by using the method of SSF of A. oryzae. The experiment result will provide an important theoretical basis for solving current shortage of protein feed resources.
