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41.
地方时与区时在电离层研究中的差异 总被引:2,自引:0,他引:2
本文指出混淆地时与区时两个时间概念在电离层研究中带来的差异的严重性,建议使用地方与区时这两个名词,而抛弃“本地时”和“当地时”等容易引起混淆的名词。 相似文献
42.
Yanyun Jiang Yuanjie Zheng Xiaodan Sui Wanzhen Jiao Yunlong He Weikuan Jia 《计算机系统科学与工程》2021,36(3):537-549
Multispectral imaging (MSI) technique is often used to capture images of the fundus by illuminating it with different wavelengths of light. However, these images are taken at different points in time such that eyeball movements can cause misalignment between consecutive images. The multispectral image sequence reveals important information in the form of retinal and choroidal blood vessel maps, which can help ophthalmologists to analyze the morphology of these blood vessels in detail. This in turn can lead to a high diagnostic accuracy of several diseases. In this paper, we propose a novel semi-supervised end-to-end deep learning framework called “Adversarial Segmentation and Registration Nets” (ASRNet) for the simultaneous estimation of the blood vessel segmentation and the registration of multispectral images via an adversarial learning process. ASRNet consists of two subnetworks: (i) A segmentation module S that fulfills the blood vessel segmentation task, and (ii) A registration module R that estimates the spatial correspondence of an image pair. Based on the segmention-driven registration network, we train the segmentation network using a semi-supervised adversarial learning strategy. Our experimental results show that the proposed ASRNet can achieve state-of-the-art accuracy in segmentation and registration tasks performed with real MSI datasets. 相似文献
43.
Jiao Feng Naixue Xiong Laurence T. Yang Yan Yang 《Multimedia Tools and Applications》2012,56(2):227-243
With the advent of Next Generation Network (NGN), services that are currently provided by multiple specific network-centric
architectures. NGN provides AAA (Anytime, Anywhere and Always on) access to users from different service providers with consistent
and ubiquitous provision of services as necessary. This special issue of NGN includes pervasive, grid, and peer-to-peer computing
to provide computing and communication services at anytime and anywhere. In fact, the application of NGN includes digital
image processing, multimedia systems/services, and so on. Here we focus on the digital image processing technology in NGN
environments. Low-contrast structure and heavy noise in NGN environments can be found in many kinds of digital images, which
makes the images vague and uncertainly, especially in x-ray images. As result, some useful tiny characteristic are weakened—which
are difficult to distinguish even by naked eyes. Based on the combination of no-linear grad-contrast operator and multi-resolution
wavelet analysis, a kind of image enhancement processing algorithm for useful tiny characters is presented. The algorithm
can enhance the tiny characters while confine amplifying noise. The analysis of the results shows that local regions of the
image are enhanced by using the concept of the grad contrast to make image clearer adaptively. Experiments were conducted
on real pictures, and the results show that the algorithm is flexible and convenient. 相似文献
44.
Jian-Min Jiao 《国际自动化与计算杂志》2012,9(1):8-15
The robust stability and robust stabilization problems for discrete singular systems with interval time-varying delay and linear fractional uncertainty are discussed. A new delay-dependent criterion is established for the nominal discrete singular delay systems to be regular, causal and stable by employing the linear matrix inequality (LMI) approach. It is shown that the newly proposed criterion can provide less conservative results than some existing ones. Then, with this criterion, the problems of robust stability and robust stabilization for uncertain discrete singular delay systems are solved, and the delay-dependent LMI conditions are obtained. Finally, numerical examples are given to illustrate the e?ectiveness of the proposed approach. 相似文献
45.
从飞机制造的角度出发,以IETM技术为基础,以带Windows 7操作系统的便携式终端为硬件平台,研究开发应用于某机机载机电设备装配指导的交互式电子工卡系统。文中主要介绍了系统设计的背景知识、开发架构和软硬件实现方法,结合XML和SQL数据库技术创作符合GJB6600标准的应用系统。该系统的成功研制和投入使用可将电子信息技术的最新研究成果用于生产实践,既可有效地减轻生产一线工作人员的劳动强度,又能极大地提高飞机数字化制造效率。 相似文献
46.
47.
Ma Xin Zhang Guoqiang Li Fengting Jiao Mingyang Yao Shunyu Chen Zhipeng Liu Ziyong Zhang Yongyu Lv Ming Liu Licheng 《Catalysis Letters》2021,151(10):2939-2949
Catalysis Letters - Microbial electrosynthesis (MES) is an effective approach to driving the CO2 reduction to multi-carbon organic products using renewable energy. In this work, the MES of acetate... 相似文献
48.
Asako Yamamoto Lingli Yang Yasutaka Kuroda Jiao Guo Lanting Teng Daisuke Tsuruta Ichiro Katayama 《International journal of molecular sciences》2021,22(1)
As the outermost barrier of the body, skin is a major target of oxidative stress. In the brain, estrogen has been reported synthesized locally and protects neurons from oxidative stress. Here, we explored whether estrogen is also locally synthesized in the skin to protect from oxidative stress and whether aberrant local estrogen synthesis is involved in skin disorders. Enzymes and estrogen receptor expression in skin cells were examined first by quantitative real-time PCR and Western blot analyses. Interestingly, the estrogen synthesis enzyme was mainly localized in epidermal keratinocytes and estrogen receptors were mainly expressed in melanocytes among 13 kinds of cultured human skin cells. The most abundant estrogen synthesis enzyme expressed in the epidermis was 17β-hydroxysteroid dehydrogenase 1 (HSD17β1) localized in keratinocytes, and the most dominant estrogen receptor expressed in the epidermis was G protein-coupled estrogen receptor 1 (GPER1) in melanocytes. To investigate whether keratinocyte-derived estradiol could protect melanocytes from oxidative stress, cultured human primary epidermal melanocytes (HEMn-MPs) were treated with H2O2 in the presence or absence of 17β estradiol or co-cultured with HSD17β1 siRNA-transfected keratinocytes. Keratinocyte-derived estradiol exhibited protective effects against H2O2-induced cell death. Further, reduced expression of HSD17β1 in the epidermis of skin from vitiligo patients was observed compared to the skin from healthy donors or in the normal portions of the skin in vitiligo patients. Our results suggest a possible new target for interventions that may be used in combination with current therapies for patients with vitiligo. 相似文献
49.
Nabieu Kamara Yamin Jiao Zijun Lu Kelvin Dodzi Aloryi Jinwen Wu Xiangdong Liu Muhammad Qasim Shahid 《International journal of molecular sciences》2021,22(2)
Neo-tetraploid rice with high fertility is a useful germplasm for polyploid rice breeding, which was developed from the crossing of different autotetraploid rice lines. However, little information is available on the molecular mechanism underlying the fertility of neo-tetraploid rice. Here, two contrasting populations of tetraploid rice, including one with high fertility (hereafter referred to as JG) and another with low fertility (hereafter referred to as JD), were generated by crossing Huaduo 3 (H3), a high fertility neo-tetraploid rice that was developed by crossing Jackson-4x with 96025-4x, and Huajingxian74-4x (T452), a low fertility autotetraploid rice parent. Cytological, global genome sequencing-based bulked-segregant (BSA-seq) and CRISPR/Cas9 technology were employed to study the genes associated with pollen fertility in neo-tetraploid rice. The embryo sacs of JG and JD lines were normal; however, pollen fertility was low in JD, which led to scarce fertilization and low seed setting. Cytological observations displayed low pollen fertility (25.1%) and approximately 31.3 and 27.2% chromosome lagging at metaphase I and II, and 28.8 and 24.8% chromosome straggling at anaphase I and II in JD, respectively. BSA-seq of F2–3 generations and RNA-seq of F4 generation detected a common fragment, i.e., 18,915,234–19,500,000, at chromosome 7, which was comprised of 78 genes associated with fertility. Among 78 genes, 9 genes had been known to be involved in meiosis and pollen development. Two mutants ny1 (LOC_Os07g32406) and ny2 (LOC_Os07g32040) were generated by CRISPR/Cas9 knockout in neo-tetraploid rice, and which exhibited low pollen fertility and abnormal chromosome behavior. Our study revealed that two unknown genes, LOC_Os07g32406 (NY1) and LOC_Os07g32040 (NY2) play an important role in pollen development of neo-tetraploid rice and provides a new perspective about the genetic mechanisms of fertility in polyploid rice. 相似文献
50.