We present evidences showing that the Be star 3G71, proposed as the optical cou- nterpart of the Be / X-ray binary source 1H2214 + 589, may be a Herbig Ae / Be star. These evidences can be summarized as follows. 1. We...We present evidences showing that the Be star 3G71, proposed as the optical cou- nterpart of the Be / X-ray binary source 1H2214 + 589, may be a Herbig Ae / Be star. These evidences can be summarized as follows. 1. We made spectroscopic observations by using a CCD spectrograph with dispersi- ons 50 A / mm and 195 A / mm at the BAO 2.16m telescope. Analysis of the optical spectra of 3G71 indicates: a. Forbidden lines, such as [OI] 6300 and 6363 A, [FeII] 5527, 4889, 4814, 4415, 4359 and 4304 A, are present in the spectra (Fig.2a, Fig.2b). b. The Hα emission line is unusually strong. Its equivalent width is sometimes more than 100 A (Fig. 1). The photospheric absorption lines of hydrogen are very wide. In the case of Hβ, the distance between two wings amounts to 60 A (Fig.2a, Fig.3). 2. We have performed cross-identification between HST GSC catalogue and IRAS Point Source Catalogue and found the IRAS point souree counterpart of 3G71 to be 2248 + 6058. Its equatorial coordinates (at equinox 1950.0) are 22h24m53s.8 and +60°58′ 15″, while those given by the GSC catalogue are 22h24m53s.37 and +60°58′13″.1. The differences are merely 0.4s and 2″, being less than the uncertainty ellipse (major axis: 11″, minor axis: 6″) given in IRAS PSC. Table 1 lists the flux densities quoted from IRAS GSC and the deduced IRAS IR magnitudes. It is clear from the table that 3G71 has a very large IR color excess, since the V magnitude of 3G71 found from GSC is 12.2 and its V-[25]=+12.47, which is much larger than that expected for classical Be stars and satisfies the criterion for the Herbig Ae / Be stars given by Hu et al., i.e., V-[25] > 7. 3. Using Palomar sky survey map, we have made a search for a nebulosity in the immediate vicinity of 3G71 and actually discovered a bright nebula, at whose center 3G71 is just located. Its diameter is about 1 are-minute. It is concluded from the characteristics of 3G71 mentioned above that 3G71 may be a Herbig Ae / Be star.展开更多
空调热交换器性能异常检测技术是快速判断民机空调系统运行状态并合理安排维修任务的关键,传统的异常检测方法难以有效处理高维时序数据,无法实现系统早期故障预警。为此,本文提出了一种基于长短期记忆网络(LSTM,long-short term memory...空调热交换器性能异常检测技术是快速判断民机空调系统运行状态并合理安排维修任务的关键,传统的异常检测方法难以有效处理高维时序数据,无法实现系统早期故障预警。为此,本文提出了一种基于长短期记忆网络(LSTM,long-short term memory)与自编码器(AE,autoencoder)模型的无监督异常检测方法,用以识别民机空调系统异常运行状态。首先,基于民机空调系统原始传感器参数构建表征空调热交换器性能的特征监测参数;其次,构建LSTM-AE模型进行数据特征重构并计算重构误差;最后,使用孤立森林(iForest, isolation forest)进行无监督异常监测。将本文构建的无监督异常检测方法与传统方法对比,并建立模型评估指标,验证结果表明,所构建的模型方法可以对民机空调热交换器性能异常状态进行有效检测。展开更多
To address the issues of incomplete information,blurred details,loss of details,and insufficient contrast in infrared and visible image fusion,an image fusion algorithm based on a convolutional autoencoder is proposed...To address the issues of incomplete information,blurred details,loss of details,and insufficient contrast in infrared and visible image fusion,an image fusion algorithm based on a convolutional autoencoder is proposed.The region attention module is meant to extract the background feature map based on the distinct properties of the background feature map and the detail feature map.A multi-scale convolution attention module is suggested to enhance the communication of feature information.At the same time,the feature transformation module is introduced to learn more robust feature representations,aiming to preserve the integrity of image information.This study uses three available datasets from TNO,FLIR,and NIR to perform thorough quantitative and qualitative trials with five additional algorithms.The methods are assessed based on four indicators:information entropy(EN),standard deviation(SD),spatial frequency(SF),and average gradient(AG).Object detection experiments were done on the M3FD dataset to further verify the algorithm’s performance in comparison with five other algorithms.The algorithm’s accuracy was evaluated using the mean average precision at a threshold of 0.5(mAP@0.5)index.Comprehensive experimental findings show that CAEFusion performs well in subjective visual and objective evaluation criteria and has promising potential in downstream object detection tasks.展开更多
分布式显示控制系统(以下简称分布式)被广泛应用于指挥调度、视频会议、信息发布等领域,是高清视频信号传输和调度的核心,也担负着大量音频信号的传输和调度任务。分布式在与音频扩声系统之间相互传输音频信号时,通常需要通过非平衡模...分布式显示控制系统(以下简称分布式)被广泛应用于指挥调度、视频会议、信息发布等领域,是高清视频信号传输和调度的核心,也担负着大量音频信号的传输和调度任务。分布式在与音频扩声系统之间相互传输音频信号时,通常需要通过非平衡模拟信号线缆实现,存在多次数模(Digital to Analog,D/A)和模数(Analog to Digital,A/D)转换,造成音频信号质量显著下降和精度损失。针对该问题,提出将AES67音频网关作为分布式和音频扩声系统之间的桥梁,在2个系统之间通过AES67实现网际互连协议(Internet Protocol,IP)全数字方式转换与传输,保证高质量的音频传输和性能。展开更多
文摘We present evidences showing that the Be star 3G71, proposed as the optical cou- nterpart of the Be / X-ray binary source 1H2214 + 589, may be a Herbig Ae / Be star. These evidences can be summarized as follows. 1. We made spectroscopic observations by using a CCD spectrograph with dispersi- ons 50 A / mm and 195 A / mm at the BAO 2.16m telescope. Analysis of the optical spectra of 3G71 indicates: a. Forbidden lines, such as [OI] 6300 and 6363 A, [FeII] 5527, 4889, 4814, 4415, 4359 and 4304 A, are present in the spectra (Fig.2a, Fig.2b). b. The Hα emission line is unusually strong. Its equivalent width is sometimes more than 100 A (Fig. 1). The photospheric absorption lines of hydrogen are very wide. In the case of Hβ, the distance between two wings amounts to 60 A (Fig.2a, Fig.3). 2. We have performed cross-identification between HST GSC catalogue and IRAS Point Source Catalogue and found the IRAS point souree counterpart of 3G71 to be 2248 + 6058. Its equatorial coordinates (at equinox 1950.0) are 22h24m53s.8 and +60°58′ 15″, while those given by the GSC catalogue are 22h24m53s.37 and +60°58′13″.1. The differences are merely 0.4s and 2″, being less than the uncertainty ellipse (major axis: 11″, minor axis: 6″) given in IRAS PSC. Table 1 lists the flux densities quoted from IRAS GSC and the deduced IRAS IR magnitudes. It is clear from the table that 3G71 has a very large IR color excess, since the V magnitude of 3G71 found from GSC is 12.2 and its V-[25]=+12.47, which is much larger than that expected for classical Be stars and satisfies the criterion for the Herbig Ae / Be stars given by Hu et al., i.e., V-[25] > 7. 3. Using Palomar sky survey map, we have made a search for a nebulosity in the immediate vicinity of 3G71 and actually discovered a bright nebula, at whose center 3G71 is just located. Its diameter is about 1 are-minute. It is concluded from the characteristics of 3G71 mentioned above that 3G71 may be a Herbig Ae / Be star.
文摘空调热交换器性能异常检测技术是快速判断民机空调系统运行状态并合理安排维修任务的关键,传统的异常检测方法难以有效处理高维时序数据,无法实现系统早期故障预警。为此,本文提出了一种基于长短期记忆网络(LSTM,long-short term memory)与自编码器(AE,autoencoder)模型的无监督异常检测方法,用以识别民机空调系统异常运行状态。首先,基于民机空调系统原始传感器参数构建表征空调热交换器性能的特征监测参数;其次,构建LSTM-AE模型进行数据特征重构并计算重构误差;最后,使用孤立森林(iForest, isolation forest)进行无监督异常监测。将本文构建的无监督异常检测方法与传统方法对比,并建立模型评估指标,验证结果表明,所构建的模型方法可以对民机空调热交换器性能异常状态进行有效检测。
文摘To address the issues of incomplete information,blurred details,loss of details,and insufficient contrast in infrared and visible image fusion,an image fusion algorithm based on a convolutional autoencoder is proposed.The region attention module is meant to extract the background feature map based on the distinct properties of the background feature map and the detail feature map.A multi-scale convolution attention module is suggested to enhance the communication of feature information.At the same time,the feature transformation module is introduced to learn more robust feature representations,aiming to preserve the integrity of image information.This study uses three available datasets from TNO,FLIR,and NIR to perform thorough quantitative and qualitative trials with five additional algorithms.The methods are assessed based on four indicators:information entropy(EN),standard deviation(SD),spatial frequency(SF),and average gradient(AG).Object detection experiments were done on the M3FD dataset to further verify the algorithm’s performance in comparison with five other algorithms.The algorithm’s accuracy was evaluated using the mean average precision at a threshold of 0.5(mAP@0.5)index.Comprehensive experimental findings show that CAEFusion performs well in subjective visual and objective evaluation criteria and has promising potential in downstream object detection tasks.
文摘分布式显示控制系统(以下简称分布式)被广泛应用于指挥调度、视频会议、信息发布等领域,是高清视频信号传输和调度的核心,也担负着大量音频信号的传输和调度任务。分布式在与音频扩声系统之间相互传输音频信号时,通常需要通过非平衡模拟信号线缆实现,存在多次数模(Digital to Analog,D/A)和模数(Analog to Digital,A/D)转换,造成音频信号质量显著下降和精度损失。针对该问题,提出将AES67音频网关作为分布式和音频扩声系统之间的桥梁,在2个系统之间通过AES67实现网际互连协议(Internet Protocol,IP)全数字方式转换与传输,保证高质量的音频传输和性能。
