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Development of analytical methods for polycyclic aromatic hydrocarbons (PAHs) in airborne particulates: A review

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Journal of Environmental Sciences 2007年第1期19卷 1-11页

作者： liu li-bin liu Yan liN Jin-ming TANG Ning HAYAKAWA Kazuichi MAEDA Tsuneaki State Key Laboratory of Environmental Chemistry and Ecotoxicology. Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085. China Graduate School of Natural Science and Technology Faculty of Pharmaceutical Sciences Kanazawa University Kakuma-machi. Kanazawa 920-1192. Japan Innovation Center for Start-ups （INCS）. National Institute of Advanced Industrial Science and Technology. 2-2-2 Marunouchi ChiyodakuTokyo 100-0005 Japan

In the present work, the different sample collection, pretreatment and analytical methods for polycyclic aromatic hydrocarbons （PAHs） in airborne particulates is systematacially reviewed, and the applications of these pretreatment and analytical methods for PAHs are compared in detail. Some comments on the future expectation are also presented.

关键词： polycyclic aromatic hydrocarbons (PAHs) airborne particulates analytical methods review

An Image Encryption Method Based on Bit Plane Hiding Technology

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Wuhan University Journal of Natural Sciences 2006年第5期11卷 1283-1286页

作者： liu bin li Zhitang TU Hao Network and Computing Center Huazhong Universityof Science and Technology Wuhan 430074 Hubei China

A novel image hiding method based on the correlation analysis of bit plane is described in this paper. Firstly, based on the correlation analysis, different bit plane of a secret image is hided in different bit plane of several different open images. And then a new hiding image is acquired by a nesting ＂Exclusive-OR＂ operation on those images obtained from the first step. At last, by employing image fusion technique, the final hiding result is achieved. The experimental result shows that the method proposed in this paper is effec rive.

关键词： image hiding image fusion bit plane correlation analysis

Estimating aboveground biomass using Pléiades satellite image in a karst watershed of Guizhou Province,Southwestern China

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Journal of Mountain Science 2018年第5期15卷 1020-1034页

作者： GUO Yin-ming NI Jian liu li-bin WU Yang-yang GUO Chun-zi XU Xin ZHONG Qiao-lian State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550081 China Puding Karst Ecosystem Research Station Chinese Academy of Sciences Puding 562100 China University of Chinese Academy of Sciences Beijing 100049 China College of Chemistry and life Sciences Zhejiang Normal University Jinhua 321004 China

Biomass in karst terrain has rarely been measured because the steep mountainous limestone terrain has limited the ability to sample woody *** observation, especially at high spatial resolution, is an important surrogate for the quantification of the biomass of karst forests and shrublands. In this study, an artificial neural network(ANN) model was built using Pléiades satellite imagery and field biomass measurements to estimate the aboveground biomass(AGB) in the Houzhai River Watershed, which is a typical plateau karst basin in Central Guizhou Province, Southwestern China. A back-propagation ANN model was also *** vegetation indices, two spectral bands of Pléiades imagery, one geomorphological parameter,and land use/land cover were selected as model inputs. AGB was chosen as an output. The AGB estimated by the allometric functions in 78 quadrats was utilized as training data(54 quadrats, 70%),validation data(12 quadrats, 15%), and testing data(12 quadrats, 15%). Data-model comparison showed that the ANN model performed well with an absolute root mean square error of 11.85 t/ha, which was 9.88%of the average AGB. Based on the newly developed ANN model, an AGB map of the Houzhai River Watershed was produced. The average predicted AGB of the secondary evergreen and deciduous broadleaved mixed forest, which is the dominant forest type in the watershed, was 120.57 t/ha. The average AGBs of the large distributed shrubland,tussock, and farmland were 38.27, 9.76, and 11.69 t/ha, respectively. The spatial distribution pattern ofthe AGB estimated by the new ANN model in the karst basin was consistent with that of the field investigation. The model can be used to estimate the regional AGB of karst landscapes that are distributed widely over the Yun-Gui Plateau.

关键词： Aboveground biomass Secondary karstforest Artificial neural network Vegetation indices Very high resolution satellite image

Novel modified min-sum decoding algorithm for low-density parity-check codes

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The Journal of China Universities of Posts and Telecommunications 2010年第4期17卷 1-5,46页

作者： liu Hai-yang , QU Wen-ze, liu bin, li Jiang-peng, LUO Shi-dong, CHEN Jie Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029, China Institute of Microelectronics Chinese Academy of Sciences Beijing 100029 China

The problem of improving the performance of min-sum decoding of low-density parity-check （LDPC） codes is considered in this paper. Based on min-sum algorithm, a novel modified min-sum decoding algorithm for LDPC codes is proposed. The proposed algorithm modifies the variable node message in the iteration process by averaging the new message and previous message if their signs are different. Compared with the standard min-sum algorithm, the modification is achieved with only a small increase in complexity, but significantly improves decoding performance for both regular and irregular LDPC codes. Simulation results show that the performance of our modified decoding algorithm is very close to that of the standard sum-product algorithm for moderate length LDPC codes.

关键词： LDPC codes sum-product algorithm min-sum algorithm modified min-sum algorithm

Monthly Seasonality in the Top 50 Australian Stocks

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Journal of Modern Accounting and Auditing 2011年第4期7卷 380-390页

作者： liu Benjamin li bin Griffith University Australia

We studied monthly seasonality in the top 50 Australian stocks across different industry sectors. Unlike other Australian studies, we examined monthly seasonality using stock return data of individual companies for the period of January 1980 through to August 2010. We found that stock returns of over half of the 50 companies are significantly positive in April and December, and most companies have low stock returns in October. Seven companies have higher returns in April than in other months of the year, most of which are banking and financial services companies, while six companies have lower returns in February than in other months. Although Australia has a July-June taxation cycle, we found that only three stocks have a July anomaly. The findings are inconsistent with the tax-loss selling hypothesis and other studies on the Australian equity markets （e.g., Brown, Keim, Kleidon, ＆ Marsh, 1983; Brailsford ＆ Easton, 1991）. However, our findings are generally consistent with Bonin and Moses （1974） on individual stock seasonality

关键词： Australian stock market market efficiency market anomaly monthly effect January effect seasonality

An improved Gaussian frequency domain sparse inversion method based on compressed sensing

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Applied Geophysics 2020年第3期17卷 443-452页

作者： liu Yang Zhang Jun-Hua Wang Yan-Guang liu li-bin li Hong-Mei School of Geosciences China University of Petroleum(East China)Qingdao 266580China Geophysical Research Institute of Shengli Oilfi eld Branch Company SinopecDongying 257022China.

The traditional compressed sensing method for improving resolution is realized in the frequency *** method is aff ected by noise,which limits the signal-to-noise ratio and resolution,resulting in poor *** solve this problem,we improved the objective function that extends the frequency domain to the Gaussian frequency domain having denoising and smoothing ***,the reconstruction of the sparse refl ection coeffi cient is implemented by the mixed L1_L2 norm algorithm,which converts the L0 norm problem into an L1 norm ***,a fast threshold iterative algorithm is introduced to speed up convergence and the conjugate gradient algorithm is used to achieve debiasing for eliminating the threshold constraint and amplitude *** model test indicates that the proposed method is superior to the conventional OMP and BPDN *** not only has better denoising and smoothing eff ects but also improves the recognition accuracy of thin *** actual data application also shows that the new method can eff ectively expand the seismic frequency band and improve seismic data resolution,so the method is conducive to the identifi cation of thin interbeds for beach-bar sand reservoirs.

关键词： Compressed sensing Gaussian frequency domain L1-L2 norm thin interbeds beach-bar sand resolution signal-to-noise ratio

VTI介质角度域Kirchhoff叠前时间偏移方法

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中国石油大学学报（自然科学版） 2012年第5期36卷 51-55页

作者：刘立彬中国科学院地质与地球物理研究所北京100029 中国石化胜利油田分公司物探研究院山东东营257022

为了支持VTI介质下的振幅随偏移距/入射角变化(AVO/AVA)技术,提出一种基于射线追踪的VTI介质角度域Kirchhoff叠前时间偏移方法。从VTI介质反射波时距关系出发,通过稳健的射线追踪算法建立反射走时和界面上入射角的数值表,进而估算射线... 详细信息

为了支持VTI介质下的振幅随偏移距/入射角变化(AVO/AVA)技术,提出一种基于射线追踪的VTI介质角度域Kirchhoff叠前时间偏移方法。从VTI介质反射波时距关系出发,通过稳健的射线追踪算法建立反射走时和界面上入射角的数值表,进而估算射线路径对应的双程走时及入射角,利用脉冲响应叠加方法实现叠前时间偏移,得到构造图像和角度域共成像点道集。由于在振幅加权因子求取时考虑射线弯曲效应的影响,因此成像保幅性更好。所提方法获得的角度域共成像点道集同相轴平直,且有效入射角度范围更宽,有利于后续的AVO/AVA或反演处理。理论模型合成数据和实际地震资料测试结果展示了方法的优越性与实用性。

关键词： VTI介质射线追踪角度域成像叠前时间偏移

CoTCPP integrates with BiOBr microspheres for improved solar-driven CO_(2)reduction performance

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Green Energy & Environment 2025年第1期10卷 193-202页

作者： lina li Yi Zhang Gaopeng liu Tiange Wei Junze Zhao bin Wang Mengxia Ji Yuanbin She Jiexiang Xia Huaming li School of Chemistry and Chemical Engineering Institute for Energy ResearchJiangsu University301 Xuefu RoadZhenjiang212013China State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology College of Chemical EngineeringZhejiang University of TechnologyHangzhou310014China

CO_(2) photoreduction into carbon-based chemicals has been considered as an appropriate way to alleviate the energy issue and greenhouse ***,the 5,10,15,20-tetra(4-carboxyphenyl)porphyrin cobalt(II)(CoTCPP)has been integrated with BiOBr microspheres and formed the CoTCPP/BiOBr *** as-prepared CoTCPP/BiOBr-2 composite shows optimized photocatalytic performance for CO_(2) conversion into CO and CH_(4) upon irradiation with 300 W Xe lamp,which is 2.03 and 2.58 times compared to that of BiOBr,*** introduced CoTCPP significantly enhanced light absorption properties,promoted rapid separation of photogenerated carriers and boosted the chemisorption of CO_(2) *** metal Co^(2+) at the center of the porphyrin molecules also acts as adsorption center for CO_(2) molecules,accelerating the CO_(2) conversion into CO and *** possible mechanism of CO_(2) photoreduction was explored by in-situ FT-IR *** work offers a new possibility for the preparation of advanced photocatalysts.

关键词： BiOBr CoTCPP CO_(2)photoreduction Carriers transfer CO_(2)adsorption-activation

A Scalable Intrusion Detection System for IPv6

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Wuhan University Journal of Natural Sciences 2006年第6期11卷 1723-1726页

作者： liu bin li Zhitang li Zhanchun Network and Computing Center Huazhong University of Science and Technology Wuhan 430074 Hubei China

The next generation protocol IPv6 brings the new challenges to the information security. This paper presents the design and implementation of a network based intrusion detection system that support both IPv6 protocol and IPv4 protocol. This system＇s architecture is focused on performance, simplicity, and scalability. There are four primary subsystems that make it up： the packet capture, the packet decoder, the detection engine, and the logging and alerting subsystem. This paper further describes a new approach to packet capture whose goal is to improve the performance of the capture process at high speeds. The evaluation shows that the system has a good performance to detect IPv6 attacks and IPv4 attacks, and achieves 61% correct detection rate with 20% false detection rate at the speed of 100 Mb·s^-1.

关键词： intrusion detection system ipv6 packet capture