Cellulose carbamates (CC) were synthesized with microcrystalline cellulose as raw materials. The Fourier transform infrared spectra of CC with different nitrogen content were recorded. The accurate results of the nitr...Cellulose carbamates (CC) were synthesized with microcrystalline cellulose as raw materials. The Fourier transform infrared spectra of CC with different nitrogen content were recorded. The accurate results of the nitrogen content for CC can be obtained by using the deconvolution method when the nitrogen content is less than 3.5%. The relationship between the nitrogen content and the absorption intensity ratio of the corresponding separated absorption peaks in FTIR spectra has been expressed bg an equation precisely.展开更多
The double pulse sources （DPS） method is presented for linear track estimation in this work. In the field of noise identification of underwater moving target, the Doppler will distort the frequency and amplitude of ...The double pulse sources （DPS） method is presented for linear track estimation in this work. In the field of noise identification of underwater moving target, the Doppler will distort the frequency and amplitude of the radiated noise. To eliminate this, the track estimation is necessary. In the DPS method, we first estimate bearings of two sinusoidal pulse sources installed in the moving target through baseline positioning method. Meanwhile, the emitted and recorded time of each pulse are also acquired. Then the linear track parameters will be achieved based on the geometry pattern with the help of double sources spacing. The simulated results confirm that the DPS improves the performance of the previous double source spacing method. The simulated experiments were carried out using a moving battery car to further evaluate its performance. When the target is 40-60m away, the experiment results show that biases of track azimuth and abeam distance of DPS are under 0.6° and 3.4m, respectively. And the average deviation of estimated velocity is around 0.25m/s.展开更多
This paper presents an unsupervised approach to cluster reviews of products collected from Amazon and then generates its labels of each cluster.Instead of using a complete review,this paper splits a review into senten...This paper presents an unsupervised approach to cluster reviews of products collected from Amazon and then generates its labels of each cluster.Instead of using a complete review,this paper splits a review into sentences and considers all sentences from the reviews as inputs for Clustering.Hierarchical Agglomerative Clustering(HAC)is used to cluster sentences.The approaches of cluster labeling are also unsupervised.For labeling,three different methods have been used to find a limited number of essential words for each cluster.Extracted essential words are used to construct phrases.Constructed phrases are used as labels for each cluster.This paper compares the result of the labeling method with baseline labeling.In the result evaluation,all the labeling methods outperform the baseline method.The aim of this research is cluster labeling that makes a set of labels to describe a cluster content and distinguishes the labels from other cluster labels.展开更多
文摘Cellulose carbamates (CC) were synthesized with microcrystalline cellulose as raw materials. The Fourier transform infrared spectra of CC with different nitrogen content were recorded. The accurate results of the nitrogen content for CC can be obtained by using the deconvolution method when the nitrogen content is less than 3.5%. The relationship between the nitrogen content and the absorption intensity ratio of the corresponding separated absorption peaks in FTIR spectra has been expressed bg an equation precisely.
文摘The double pulse sources （DPS） method is presented for linear track estimation in this work. In the field of noise identification of underwater moving target, the Doppler will distort the frequency and amplitude of the radiated noise. To eliminate this, the track estimation is necessary. In the DPS method, we first estimate bearings of two sinusoidal pulse sources installed in the moving target through baseline positioning method. Meanwhile, the emitted and recorded time of each pulse are also acquired. Then the linear track parameters will be achieved based on the geometry pattern with the help of double sources spacing. The simulated results confirm that the DPS improves the performance of the previous double source spacing method. The simulated experiments were carried out using a moving battery car to further evaluate its performance. When the target is 40-60m away, the experiment results show that biases of track azimuth and abeam distance of DPS are under 0.6° and 3.4m, respectively. And the average deviation of estimated velocity is around 0.25m/s.
文摘This paper presents an unsupervised approach to cluster reviews of products collected from Amazon and then generates its labels of each cluster.Instead of using a complete review,this paper splits a review into sentences and considers all sentences from the reviews as inputs for Clustering.Hierarchical Agglomerative Clustering(HAC)is used to cluster sentences.The approaches of cluster labeling are also unsupervised.For labeling,three different methods have been used to find a limited number of essential words for each cluster.Extracted essential words are used to construct phrases.Constructed phrases are used as labels for each cluster.This paper compares the result of the labeling method with baseline labeling.In the result evaluation,all the labeling methods outperform the baseline method.The aim of this research is cluster labeling that makes a set of labels to describe a cluster content and distinguishes the labels from other cluster labels.
