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Mid-late Pleistocene glacial evolution in the Grove Mountains, East Antarctica, constraints from cosmogenic Be-10 surface exposure dating of glacial erratic cobbles 期刊论文 OAI收割
QUATERNARY SCIENCE REVIEWS, 2016, 卷号: 145, 期号: 0, 页码: 71-81
作者: Dong, GC (Dong, Guocheng); Huang, FX (Huang, Feixin); Caffee, MW (Caffee, Marc W.); Huang, FX; Yi, CL (Yi, Chaolu)

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Glacial HisTories From The East Antarctic Ice Sheet (Eais) Provide Keys To UnderstAndIng Correlations Between The Eats And Global Climate. They Are Especially Helpful In The Assessment Of Global Sea Level Change And As a Means Of Quantifying The Magnitude Of pAst Glacial Activity And The RAte At Which Ice Responded To climAte Change. Given The Significance Of Eais Glacial hisTories It Is Imperative That More Glacial Chronologic Data For thIs Region Be Obtained Especially For The Mid-to-lAte Pleistocene. We Report Cosmogenic Be-10 Surface Exposure DAtIng Results From Glacially Transported Cobbles Embedded In Blue-ice moraIne MAterial At Mount hardIng The Grove Mountains Eais. Forty Exotic Cobbles Sampled AlOng Two PrOfiles (a And b) On This Blue-ice MoraIne Present Apparent Exposure-ages RangIng From 7.2 To 542.2 Ka. We Explore This Scattered Dataset By UsIng PrIncipal compOnent Analysis (Pca) To Identify Statistically Significant Trends In The Data. We Identify a correlatiOn betWeen Exposure-age And Distance Of The Cobbles From Mount hardIng. In prOfile a Cobbles Further From Mount HardIng Yield Older Exposure-ages Than Those That Are Relatively Close. In Profile b Cobbles Closer To Mount HardIng Are Found To Have Relatively Older Exposure-ages. In Term Of Glacial hisTory We Suggest That The Direction Of Ice Flow Changed durIng The Period From Similar To 60 To 200 Ka And That Multiple Glacial Fluctuations Occurred In The Mid-late Pleistocene. (c) 2016 Elsevier Ltd. All Rights Reserved.

Research and optimization on media access control delay of CAN (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Information Technology and Management Innovation, ICITMI 2012, November 10, 2012 - November 11, 2012, Guangzhou, China
作者: Zhang H.; Zhang W.; Zhang W.; Zhang H.

收藏 | 浏览/下载：26/0 | 提交时间：2013/03/25

With data quantity increasing dramatically and signal transmission period becoming more and more fast the media access control delay has proved to be one of the main influence factors of CAN network real-time. Firstly an equivalent numerical simulation model of CAN bus network is built to derivate the mathematical expression of media access control delay. Secondly optimization measures are further proposed to improve the data communication real-time. At last the optimization measures tested by experiments are proved to be correct and effective. (2013) Trans Tech Publications Switzerland.

Evaluation of spatial upscaling methods based on remote sensing data with multiple spatial resolutions (EI CONFERENCE) 会议论文 OAI收割
Satellite Data Compression, Communications, and Processing VIII, August 12, 2012 - August 13, 2012, San Diego, CA, United states
Ren R.; Gu L.; Cao J.; Chen H.; Sun J.

收藏 | 浏览/下载：29/0 | 提交时间：2013/03/25

In most applications of remote sensing data special spatial information is required from a finer to a coarser spatial resolution with appropriate upscaling methods. The purpose of this paper is to compare and evaluate current spatial upscaling methods using MODIS remote sensing data with multiple spatial resolutions. In the research Northeast China was selected as the study area. MODIS data with spatial resolutions of 250 m (2 bands) and 500 m (7 bands) were used as the test data. Through using the selected upscaling methods the Band 1 and Band 2 data of MODIS were scaled up from 250 m to 500 m spatial resolution. On the basis of land cover characteristics of Northeast China the MODIS data located in the study area was classified into the five land cover types including water grasslands forests farmlands and bare lands using maximum likelihood method. The land cover classification results were further compared with MODIS Land Cover Type product. Finally Structural Similarity (SSIM) was selected to evaluate the effects of these upscaling methods. The research can provide more useful information for spatial scaling transformation in remote sensing data applications. 2012 SPIE.

Research on energy characteristics of aerospace relay mirror system (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Electronic and Mechanical Engineering and Information Technology, EMEIT 2011, August 12, 2011 - August 14, 2011, Harbin, China
Liu C.; Zhong X.; Piao Y.; Jin G.

收藏 | 浏览/下载：28/0 | 提交时间：2013/03/25

Aerospace Relay Mirror System (ARMS) as a new concept weapon used in reflection of High Energy Laser (HEL) in space is studied. It extends the attacking range of Ground Based Laser (GBL) weapons enormously. Relevant researches have been carried out for many years. The structures and operating theory of the entire system consists of ground-based high energy laser weapon and space-based relay mirror. The main work of this study is focused on the analysis of relay mirror energy characteristics to deduce the relationship among the attacking range of weapon and diameter of ARMS and target irradiance. Calculation examples are also given. The results proved the strong points and feasibility of ARMS theoretically further. It is summarized that more importance should be attached to ARMS development. The results given in this paper can be reference of an actual ARMS system to some extends. 2011 IEEE.

The effectiveness of real-time embedded software testing (EI CONFERENCE) 会议论文 OAI收割
2011 9th International Conference on Reliability, Maintainability and Safety: Safety First, Reliability Primary, ICRMS'2011, June 12, 2011 - June 15, 2011, Guiyang, China
Zhang B.; Shen X.

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Real-time embedded software is widely applied in the fields with high reliability and security like aviation and space flight etc. In those systems software quality is of vital importance and software testing as a means of guaranteeing the quality of software is gaining increasingly more attention. The effectiveness of software testing enables people to gain confidence in software correctness. The real-time and embedding features of embedded software lead to the particularity in real-time embedded software testing. On the basis of particularity analysis of embedded software testing the author of this thesis further conducted research on the effective Software Testing and proved that it is valid to adopt testing techniques and strategies through experiments. 2011 IEEE.

Design of compound Fresnel-R lenses for new high-efficient photovoltaic concentrator (EI CONFERENCE) 会议论文 OAI收割
Nonimaging Optics: Efficient Design for Illumination and Solar Concentration VII, August 1, 2010 - August 4, 2010, San Diego, CA, United states
作者: Liu H.; Liu H.; Liu H.

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A new design of compound Fresnel-R concentrator is presented which is composed of two lenses: a primary lens (Fresnel lens) that works by total internal reflection at outer facets but refraction at inner facets and a secondary lens that works by refraction. In contrast to previous Fresnel lens concentrator this design increases the acceptance angle improves the irradiance uniformity on the solar cell and reduces the aspect ratio significantly. Another outstanding advantage of this concentrator is the fact that it mainly works by performing total internal reflection reducing chromatic dependence as well as Fresnel losses. An optical efficiency more than 80% can be achieved. Moreover in order to reduce the influence of manufacture accuracy and to increase the optical efficiency further the central part of the bottom of the secondary lens which directly adhered to the solar cell is designed as a cone-shaped prism to collect the sunlight that doesn't reach the solar cell. 2010 SPIE.

Optical transmission system based on 10GBASE-X (EI CONFERENCE) 会议论文 OAI收割
2010 3rd International Conference on Advanced Computer Theory and Engineering, ICACTE 2010, August 20, 2010 - August 22, 2010, Chengdu, China
作者: Gao S.-J.

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In order to further enhance the bandwidth of the data communication system in theodolite The whole design of the PMD is realized by using Xenpak optical module. Its duty is responsible for converting 4-channel parallel 3.125Gbps data stream into a serial 10.3126Gbps data stream a single channel serial optical transmission system was designed based on the studying of the 10BASE-X Gigabit Ethernet physical layer technology which meets the IEEE standard. The conversion between the 64-bit 156.25MHz TTL signals and the 4 channel 3.125Gbps PCML differential signals is carried out by FPGA and sending out it in the form of light signals. The experimental results show that data transmission capacity was achieved a 10Gbps in the single-channel optical transmission system. It can conduct short distance transmission. The system delay is about 31lns. The bit error rates no more than 10-12 which satisfies the system demand. 2010 IEEE.

Experiments of second harmonic generation output in pulsed TEA CO 2 laser (EI CONFERENCE) 会议论文 OAI收割
High-Power Lasers and Applications V, October 18, 2010 - October 19, 2010, Beijing, China
作者: Li D.

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It is always the hot subject to realize the output of high-power laser in the range of 3-5m wavelength. This rang of wave band has greatly important applications in military because it located in the atmosphere window. Generally there are two ways to obtain this range of laser wavelength. One way is through optical parameter oscillation (OPO) from shorter laser wavelength and the other is through second harmonic generation (SHG) from longer laser wavelength. Firstly the comparison between tow nonlinear crystals ZnGeP2 and AgGaSe2 is conducted for their nonlinear coefficient and damaging threshold in theory. The theoretical results show that the crystal AgGaSe 2 is more suitable for the SHG of pulsed TEA CO2 laser. When using pulsed TEA CO2 laser with wavelength of 9.3m to pumping AgGaSe2 SHG crystal the wavelength of 4.65m is obtained. In the condition of repetition rate 100Hz the upmost output power of single pulse is up to level of 1W which corresponding efficiency of SHG is about 6%. The experimental results show that the polarization of laser beam has greatly influence on the SHG output of the crystal. Under the radiation of 3MW/cm 2 from fundamental wave and the right position for maximal SHG output in the crystal when polarization of laser beam rotates 4.5 the SHG output of energy decrease about 30%. The research of this paper will make a foundation for further development of mid-infrared laser. 2010 Copyright SPIE - The International Society for Optical Engineering.

Using bidirectional binary particle swarm optimization for feature selection in feature-level fusion recognition system (EI CONFERENCE) 会议论文 OAI收割
2009 4th IEEE Conference on Industrial Electronics and Applications, ICIEA 2009, May 25, 2009 - May 27, 2009, Xi'an, China
作者: Wang D.; Wang Y.; Wang Y.; Wang Y.; Wang Y.

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In feature-level fusion recognition system the other is optimizing system sensor design to get outstanding cost performance. So feature selection become usually necessary to reduce dimensionality of the combination of multi-sensor features and improve system performance in system design. In general there are two main missions. One is improving the recognition correct rate as soon as possible the optimization is usually applied to feature selection because of its computational feasibility and validity. For further improving recognition accuracy and reducing selected feature dimensions this paper presents a more rational and accurate optimization Bidirectional Binary Particle Swarm Optimization (BBPSO) algorithm for feature selection in feature-level fusion target recognition system. In addition we introduce a new evaluating function as criterion function in BBPSO feature selection method. At the last we utilized Leave-One-Out method to validate the proposed method. The experiment results show that the proposed algorithm improves classification accuracy by two percentage points while the selected feature dimensions are less one dimension than original Particle Swarm Optimization approach with 16 original feature dimensions. 2009 IEEE.

Analysis of spectrum narrowing of diode laser bar (EI CONFERENCE) 会议论文 OAI收割
Semiconductor Lasers and Applications III, November 12, 2007 - November 13, 2007, Beijing, China
作者: Liu Y.; Wang L.; Wang L.; Wang L.; Liu Y.

收藏 | 浏览/下载：18/0 | 提交时间：2013/03/25

Laser diode bar (LDB) are used increasingly often for many applications but spectral bandwidth of LDB are generally approximately 2-4nm far too wide for many demanding applications e.g. spin-exchange optical pumping terahertz generation and lidar. External-cavity feedback can improve the spectral properties of LD or LDB. However spectrum narrowing of LDB is more difficult than that of LD. Bar curvature (i.e. "smile") produced in the manufacturing process affects the spectrum narrowing greatly. By geometrical optics approach and ORIGIN software smile which can be corrected by plano-convex cylindrical lens is simulated and the result is in good agreement with experiment. The selection of grating which is also a critical factor of spectrum narrowing will be stated. Finally an external cavity consisting of fast axis collimator two plano-convex cylindrical lens and a diffraction grating is used. The scheme is implemented on a 19-element LDB and yields 3-fold reduction in spectral linewidth under the situation that all optical elements in the system which are not optimized. Further we use a slit in the experiment and analyze the spectrum narrowing of each element in LDB.