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排序方式: 共有29条查询结果,搜索用时 15 毫秒
11.
基于单片机的IP113F光纤收发器的监控与采集   总被引:1,自引:0,他引:1  
目前,在数据网络业务中以太网光纤收发器已大量应用,网络规模越来越大,远端和局端光纤以太网设备越来越多,其维护、管理和控制等问题也越发突出。针对光纤收发器的应用和管理现状,提出一种基于单片机的IP113F光纤收发器的监控与采集系统设计方案。详细介绍了监控系统的体系结构以及软硬件组成,同时对系统的设计与实现进行详细说明,并介绍了系统的软件设计程序。最后指出该系统的不足之处且监控距离比较短。  相似文献   
12.
In order to overcome the difficulty brought by the circling charged tracks with transverse momentum less than 120 MeV in the BESⅢ Main Drift Chamber(MDC),a specialized method called TCurlFinder was developed.This tracking method focuses on the charged track reconstruction under 120 MeV and possesses a special mechanism to reject background noise hits.The performance of the package has been carefully checked and tuned by both Monte Carlo data and real data.The study shows that this tracking method could obviously enhance the reconstruction efficiency in the low transverse momentum region,providing physics analysis with more and reliable data.  相似文献   
13.
为了改善现有的航空弹射救生系统,提高飞行员安全逃生的成功率,提出了微爆索切割技术在航空穿盖弹射救生系统中的应用。采用非线性动力显式程序LS-DYNA3D,对有机玻璃平板元件、航空舱盖的微爆索切割过程进行了数值计算分析,得到了不同装药量下有机玻璃平板元件、航空舱盖的切割深度,对比了有机玻璃的几何形状对微爆索切割深度的影响。模拟结果表明:有机玻璃平板切割实验对航空舱盖切割实验具有一定的指导意义,研究结果也可为微爆索线性切割航空舱盖的实验设计提供依据。  相似文献   
14.
Although water supplies are prominently dependent on desalination technology, desalination plant facing severe issues of discharged brine concentrate. Membrane distillation crystallization is an emerging synergistic technology that resolves the issue of brine concentrate by recovering clean water and value-added minerals simultaneously. In the present study, properties of polyvinylidene fluoride (PVDF) membrane were modified by incorporation of exfoliated fillers of hexagonal boron nitride and polyethylene glycol. The changes in morphology, surface roughness, hydrophobicity, thermal stability, and chemical composition of the prepared membranes were evaluated by scanning electron microscopy, atomic force microscopy, contact angle, thermogravimetric analysis, Fourier-transform infrared spectroscopy, respectively. Membrane distillation crystallization experiments were conducted to observe the effect of modified membranes on the permeate flux and salts recovery at different feed temperatures. The results showed a significant improvement in the permeate flux with modified membranes compared with pure PVDF membrane. It was found that hexagonal boron nitride/polyethylene glycol200 incorporated PVDF membrane gave the higher permeate flux (3.41 kg/m2 h for K2SO4 and 2.62 kg/m2 h for KNO3) at a temperature of 80 °C along with higher salts recovery than pure PVDF membranes. A 100 h long run test was conducted on modified membranes, which showed consistency in permeate flux with a marginal increase in conductivity.  相似文献   
15.
In order to overcome the difficulty brought by the circling charged tracks with transverse momentum less than 120 MeV in the BESⅢ Main Drift Chamber (MDC), a specialized method called TCurlFinder was developed. This tracking method focuses on the charged track reconstruction under 120 MeV and possesses a special mechanism to reject background noise hits. The performance of the package has been carefully checked and tuned by both Monte Carlo data and real data. The study shows that this tracking method could obviously enhance the reconstruction efficiency in the low transverse momentum region, providing physics analysis with more and reliable data.  相似文献   
16.
Polyopes affinis is a red algal species commonly found on the South coast and near Jeju Island, Korea. This study aimed to determine whether P. affinis extracts can inhibit the pathogenesis of T-helper-2 (Th2)-mediated inflammation in a human keratinocyte cell line of atopic dermatitis (AD). Cells were incubated with 10 ng/mL of interferon gamma (IFN-γ) and 10 ng/mL of tumor necrosis factor-alpha (TNF-α) at various concentrations of PAB (10, 30, and 60 µg/mL) and PAA (100, 500, and 1000 µg/mL) extracts. A gene-ontology (GO)-enrichment analysis revealed that PAB significantly enriched the genes associated with biological processes such as cell adhesion, immune response, inflammation, and chemokine-mediated pathways. PAB suppressed the expression of the secretory proteins and mRNAs that are associated with the thymus and the production of activation-regulated chemokines (TARC/CCL17) and macrophage-derived chemokines (MDC/CCL22). The effect of the extract on mitogen-activated protein kinases (MAPKs) was related to its inhibition of TARC/CCL17 and MDC/CCL22 production by blocking NF-κB and STAT1 activation. These results suggest that seaweed extract may improve AD by regulating pro-inflammatory chemokines. In conclusion, we first confirmed the existence of phloroglucinol, a polyphenol formed from a precursor called phlorotannin, which is present in PAB, and this result proved the possibility of PAB being used as a treatment for AD.  相似文献   
17.
This paper will demonstrate a method for determining the micellar dissociation concentration (MDC) of polyoxyethylene mono n-decylether nonionic surfactants in water. Turbidity and surface tension measurements were applied to commercial samples without further purification. Complicated curves containing turbidity maxima and surface tension minima were obtained for some impure samples. It is difficult to determine the critical micellar concentration (CMC) for impure surfactants. Explanations are given for all curves obtained for pure and impure samples and the method of identifying the MDC values is illustrated. It is more practical for surfactant users to determine the MDC values in their own laboratory than to search for the CMC values in the literature when the surfactants arc impure.  相似文献   
18.
Multimedia transport has stringent bandwidth, delay, and loss requirements. It is a great challenge to support such applications in reconfigurable wireless networks (RWNs). Using multiple paths in parallel for multimedia transport provides a new degree of freedom in designing robust multimedia transport systems. In this paper, we provide a multi-path extension to zone routing protocol (ZRP) to support video transmission over RWNs. We compare ZRP and our multi-path routing scheme by using NS-2 simulator. The experiments show that our method is effective in improving the robustness of video transport over RWNs.
Shiwei YeEmail:
  相似文献   
19.
20.
A fast software one-way hash function   总被引:4,自引:0,他引:4  
One way hash functions are an important cryptographic primitive, and can be used to solve a wide variety of problems involving authentication and integrity. It would be useful to adopt a standard one-way hash function for use in a wide variety of systems throughout the world. Such a standard one-way hash function should be easy to implement, use, and understand; resistant to cryptographic attack, and should be fast when implemented in software. We present a candidate one-way hash function which appears to have these desirable properties. Further analysis of its cryptographic security is required before it can be considered for widespread use.  相似文献   
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