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Key technologies of new malicious code developments and defensive measures in communication networks

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The Journal of China Universities of Posts and Telecommunications 2010年第4期17卷 69-73页

作者： LI Peng,WANG Ru-chuan ,ZHANG Wei College of Computer,nanjing university of Posts and Telecommunications,nanjing 2.0003.China [a] College of Computer Nanjing University of Posts Telecommunications Nanjing 210003 China

This article is focused on analyzing the key technologies of new malicious code and corresponding defensive measures in the large-scale communication networks. Based on description of the concepts and development of the malicious code, the article introduces the anti-analysis technology, splitting and inserting technology, hiding technology, polymorph virus technology, and auto production technology of the malicious code trends with intelligence, diversity and integration. Following that, it summarizes the security vulnerabilities of communication networks from four related layers aspects, according to the mechanisms of malicious code in the communication networks. Finally, it proposes rapid response disposition of malicious code attacks from four correlated steps： building up the network node monitoring system, suspicious code feature automation analysis and extraction, rapid active malicious code response technique for unknown malicious code, and malicious code attack immunity technique. As a result, it actively defenses against the unknown malicious code attacks and enhances the security performance of communication networks.

关键词： network security malicious code network attack and defense malicious code defense

A non-commutative time-frequency tomography

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Chinese Science Bulletin 2007年第17期52卷 2438-2442页

作者： LIU JianCai, XU JiaKai, NING XinBao & TIAN Run Key Laboratory of modern Acoustics, Department of Electronics Science and Engineering Institute of Biological Medical Electronic Engineering, nanjing university,{2., China Key Laboratory of modern Acoustics Department of Electronics Science and Engineering Institute of Biological Medical Electronic Engineering Nanjing University Nanjing 210093 China

The characterization of non-stationary signal requires joint time and frequency information. However, time and frequency are a pair of non-commuting variables that cannot constitute a joint probability density in the time-frequency plane. The time-frequency distributions have difficult interpretation problems arising from negative and complex values or spurious components. In this paper, we get time-frequency information from the marginal distributions in rotated directions in the time-frequency plane. The rigorous probability interpretation of the marginal distributions is without any ambiguities. This time-frequency transformation is similar to the computerized axial tomography (CT or CAT) and is applied to signal analysis and signal detection and reveals a lot of advantages especially in the signal detection of the low signal/noise (S/N).

关键词：非交换时频X线断层摄影术边缘分布医学影像学时频分布

Bibracchial Lariat Ethers(Ⅰ)——The Synthesis and Crystal Structure of the N,N'-bis(2.Methoxy-1-Naphthylmethyl)-4,13.Diaza-18-Crown-6 Sodium Iodide Complex

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Chemical Research in Chinese Universities 1992年第1期8卷 48-52页

作者： Ge Yuhua, Wang Defen and Hu Hongweng (Department of Chemistry, nanjing university, nanjing)Zhou Zhongyuan and Yu Kaibei (Chengdu {2. of {3. and Determination, Academic Sinica, Chengdu)

Diaza Crown ethers are versatile complexing reagents, their complexing abilities are dramatically modified by the electron donating atoms on substituents attached to the nitrogen if they can give a three-dimensional cavity as in cryptates. Hence the synthesis and characterization of bibracchial lariat ethers (BIBLES) have received much attention. In the preparation of new BIBLES, a complex Ⅱ was unexpectedly obtained.

关键词： Bibracchial lariat ether Diaza-18-crown-6 derivative Crystal structure,Sodium iodide complex

Studies on solid state reactions of coordination compounds *** state syntheses of a family of Ag-Mo(W)-S cubane-like cluster compounds:Crystal structures of{Ag_3.oS_3.}(PPh_3._3. and{Ag_3.S_3.l}(PPh_3._3.·0.5P(S)Ph_3.3._2.^+

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Chinese Journal of Chemistry 1993年第2期11卷 126-136页

作者： LANG,Jian-Ping BAO,Shi-An ZHU,Hui-Zhen XIN,Xin-Quan Coordination Chemistry Institute,nanjing university,nanjing 2.0008YU,Kai-Bei Chengdu {3. of analysis and Measurement,Chinese Academy of Sciences,Ckengdu 610015 1Coordination Chemistry Institute Nanjing University Nanjing 2100082Chengdu Center of Analysis and Measurement Chinese Academy of Sciences Chengdu 610015

Reactions of[NH_4]_2.MS_4](M=Mo,W),AgX(X=Cl,Br,I,CN,SCN)and PPh_3.in the solid state produced six new mixed-metal sulfur containing cluster compounds,two of which,{Ag_3.oS_3.}(PPh_3._3.(1)and{Ag_3.S_3.l}(PPh_3._3.·0.5P(S)Ph_3.3._2.(2.,were determined by single crystal X-ray *** crystal data:1,triclinic,P(?),a=12.114(2.,b=13.42.(2., c=2..3.6(3.(?),α=74.53.1),β=86.73.1),γ=63.74(1)°,Z=2.R=0.043.for 4805 independent data;2.hexagonal,R3.a=b=16.2.1(3.,c=45.091(10)(?),Z=6,R=0.042.for 2.2. independent *** central unit{Ag_3.S_3.}(M=Mo,W;X=Cl,I)of the two compounds can be des- cribed as a slightly distorted cube,four corners being formed by the MS_4^(2.) ligand(with a ter- minal S atom).The remaining corners are occupied by one X(Cl or I)atom and three Ag atoms(with one PPh_3.ligand bound to each of the latter).The generation of different types of Ag-Mo(W)-S cluster compounds prepared from solid state reactions under different reaction temperatues is discussed.

关键词： Ag CI Mo WS

Crystal and Molecular Structure of Copper (Ⅱ) Dimeric Complex of S-Methyl-β-N-(Pyridine N-Oxide-2.ylmethylidene) Dithiocarbazate with Acetonitrile

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Chemical Research in Chinese Universities 1990年第4期6卷 262-265页

作者： Yu Kaibei and Zhou Zhongyuan (Chengdu center of analysis and Determination, Academia Sinica, Chengdu)Gou Shaohua, You Xiaozeng and Xu Zheng (Coordination Chemistry Institute,{2., {3.)

The crystal and molecular structure of copper(Ⅱ) dimeric complex of S-methyl-B-N-(pyridine N-oxide-2.ylmethylidene) dithiocarbazate with acetonitrile, [CuL (CH3.N)]2.(ClO4)2. was determined by X-ray diffraction. The complex crystalizes in monoclinic system with space group P2./n, a= 7. 685(2., 6=2..160(6), c= 10. 847(5) A ,B = 107.89(3., Z=2.Dc=1.788 g/cm3. F(000) = 83.. 8, u= 18. 17 cm-1(Moka,R= 0. *** Cu(Ⅱ) ion in the complex is surrounded by a distorted square pyramidal. The basal plane is comprised of S, N and O atoms of one ligand together with a N atom of the solvent--acetonitrile, while the axial position is occupied by the S atom of the other ligand. The bond length of Cu-S(bridging) is 3. 03.A . and Cu-Cu distance is 3. 700A.

关键词： Complex of Cu (Ⅱ) Crystal and molecular structure Dimeric complex S-methyl-β-N-(pyridine N-oxide-2.ylmethyndene)dithiocarbazate

Synthesis and Crystal Structure of (E)-[1-Ferrocenyl-2.(4-Chlorophenyl) ethylene]

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Chinese Journal of Structural Chemistry 1997年第4期16卷 315-319页

作者： QIAN Ying SUN Yue-Ming LIU Ju-Zheng(Department of Chemistry, Southeast university, nanjing, 2.0018)CHEN Jian HU Chun-Hua ZHENG Pei-Ju(Research {2. of {3. and Measurement, Fudan university, Shanghai, 2.O43.) 东南大学化学系江苏南京复旦大学分析测试中心上海

The single crystal structure of the donor-acceptor ferrocenyl derivativeC18H15ClFe (Mr = 3.2. 62.) has been determined, belonging to orthorhombic crystalsystem, space group P2.2.2. with lattice parameters a= 11. 3.7 (2., b= 8. 471 (2.), c=15. 42.(3. A, V= 1477. 7(9) A3. Z=4, D.= 1. 45 g. cm-3. λ(MoKα) =0. 71073.,μ= 11. 9 cm-1, F(000) = 664. The final R value for 153. observed [I>3.(I)] reflec-tions is 0. 060. The configuration of the C =C double bond is trans. The C5H4CH =CHC6H4Cl fragrnent is almost planar. The rings of ferrocene are almost in the eclipsedpositions with each other.

关键词： ferrocenyl derivative crystal structure donor-acceptor compound transconfiguration

The structure of adducts of benzaldoxime and m-chlorobenzaldoxime dehydrodimers with styrene

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Chinese Journal of Chemistry 1992年第3期10卷 278-284页

作者： HU, Hong-Wen WEI, Xu-Dong LI, Cun SUN, Hong-Zhe YAO, Yi-Ming ZHOU, Zhong-Yuan YU, Kai-Bei Department of Chemistry, nanjing university, nanjing 2.0008 Chengdu {2. of {3. and Measurment, Chinese Academy of Sciences, Chengdu 610005 1Department of Chemistry Nanjing University Nanjing 2100082Chengdu Center of Analysis and Measurment Chinese Academy of Sciences Chengdu 610005

The reaction of m-chlorobenzaldoxime dehydrodimer with styrene gives two 1:1 adducts. The main product 7 is a bisnitrone. The minor product 8 has been shown by X-ray diffraction anal- ysis to possess the structure: ArCH(N=O)CH_2.H (Ph)O--N=CHAr. The two C=N bonds are all in Z configuration. The structure of the adducts from benzaldoxime dehydrodimer and styrene is also assigned.

关键词： The structure of adducts of benzaldoxime and m-chlorobenzaldoxime dehydrodimers with styrene

Environmental archaeology of the Dachang region in the Daning Valley,the Three Gorges reservoir region of the Yangtze River,China

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Chinese Science Bulletin 2008年第S1期53卷 140-152页

作者： ZHANG Yun 1 &ZHU Cheng 2.1 State Key Laboratory of Vegetation and Environmental Change,Institute of Botany,Chinese Academy of Sciences,Beijing 100093. China 2.School of Geographic and Oceanographic Sciences,nanjing {2.,nanjing {3.,China 1. State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China 2. School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China

Environmental archaeology of archaeological sites on both sides of the Dachang section in the Daning River,the Three Gorges of the Yangtze River,shows that riverbed evolution has a great influence on the distribution of archaeological sites during the prehistorical and historical period,and it restricts human activity and the development of ancient *** investigation,dating data,paleocurrent analysis of 100 gravels on the riverbed and archaeological excavation reveal that the riverbed of the Dachang section developed in the Shuangyantang region during the early stage,after about 3. kaBP it shifted westward gradually and reached the present *** with the westward shift,the focus of ancient culture changed for several *** the Western Zhou Dynasty's period,the east riverbank of the Daning River was the main residential *** the Han Dynasty,along with the westward shift,the living space of ancient people was no longer confined to the east riverbank and the focus of culture moved *** the Zhangjiawan site became the main dwelling *** the late Han Dynasty, the villages were flooded and the ancients had to immigrate to a high *** of the Han and the Jin Dynasties outcropped on the flood plain of the east bank because their surface sediments were eroded by several flood events and the westward shift of the riverbed.

关键词： the Daning River environmental archaeology the Shuangyantang site the Zhangjiawan site tombs of the Han and the Jin Dynasties

Solar release time of solar energetic particles and associated acceleration source in corona

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Chinese Science Bulletin 2008年第2期53卷 161-168页

作者： LE GuiMing1,2.3.4, TANG YuHua1 & HAN YanBen4 1 Department of Astronomy, nanjing university,{2., China 2.Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites, China Meteorological Administration, Beijing 100081, China 3.National {2. for Space Weather, China Meteorological Administration, Beijing 100081, China 4 National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012. China Department of Astronomy Nanjing University Nanjing China Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites China Meteorological Administration Beijing China National center for Space Weather China Meteorological Administration Beijing China National Astronomical Observatories Chinese Academy of Sciences Beijing China

Solar energetic particles (SEPs) are accelerated in corona at an early phase of solar energetic particle events (SEPE). The acceleration mechanism of SEPs in corona can only be inferred from an analysis of multi-band observational data, as the observation of SEPs is usually made around 1AU. In this context, people have investigated spectrums, charge state, solar release time (SRT), and multi-band data of SEPEs, in an attempt to judge the acceleration mechanism of SEPs. The SRT computation of SEPs is an important and commonly used approach to study the acceleration mechanism of SEPs in corona. This paper reviews some important findings concerning the SRT computation of SEPs, and analyzes different merits of each approach for such calculation, based on a range of SEPE case studies. This paper also analyzes and discusses both possible and actual acceleration mechanisms of a number of SEPEs, by calculating the SRT of the SEPEs. Finally, the paper summarizes the possible problems in studying an acceleration mechanism of SEPEs inferred from the SRT of SEP.

关键词：阳光释放时间加速度电晕太阳耀斑