Table of Content

20 January 2009, Volume 45 Issue 1

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Effect of Environment Volume Change upon the Richness of Species：A Case Study of Qilihai Wetland of Tianjin

XIE Zhenglei

2009, 45(1):  183-188. 

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Researches on species extinction caused by the shrink or loss of habitat are one of the hottest points of biological study, in which numerous biological scientists have been involved. The Tianjin Qilihai Wetland was set to example to simulate the mechanism between habitat destruction and species richness. This research combined theoretical research with numeral simulation and set up the evolutional model of exponent upon the effect of human activities. 1) The exponent value of dis defined as the coefficient value of the interaction between species and environment and it can be applied to research the evolutional mechanism of different meta-population. When the condition of d<1 is met, the effect of environment on meta-population is beneficial to the development of species and habitat destruction will not lead to species extinction. While the condition of d>1 is met, the strongest species will be driven to extinguish owing to the decrease of content of habitat and the system will reach new state in a short time. The bigger the value of d is, the shorter of time system reach new state is. 2) The third mechanism of extinction of meta-population, the coordinate law of evolution and degradation of species in the restoration of destruction habitat are also found, which is the same evolutional trait of different species. The evolutional law between the restoration and destruction of habitat has same points and differences.

A Linearly Tunable Quadrature Sinusoidal Oscillator

WANG Zhanfei,LU Wengao,LI Feng,LI Zhihong

2009, 45(1):  49-53. 

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A linearly tunable quadrature sinusoidal oscillator for capacitive MEMS sensors detection circuitry is presented. The principle is based on the OTA-C techniques. The frequency is linearly tunable by tuning the Vds of the transistor operating on the triode region, and the oscillator have four outputs with different phase at 90, 180, 270, 360 degrees, respectively. The oscillator is prototyped on a 0.5μm 2P3M CMOS process, and experimental results show that the frequency can be linearly tuned from 0.18MHz to 1.2MHz and the sensitivity to VDD is 8.1%/V.

Searching for Differentially Expressed Genes by PLS-VIP Method

HAN Fang,WU Jingchen,XU Jiangfeng,DENG Minghua

2009, 45(1):  1-5. 

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A new approach called PLS-VIP based on variables' importance of projection (VIP) for detecting differentially expressed genes is proposed. It is a new method to sum up the contribution of components based on Partial Least Square method (PLS). As it takes the correlation of different genes into consideration, it is more suitable than those classification methods based on reviewing distinct genes separately. The effect of genes extracted by ordinary PLS, discriminant PLS and proposed method to classify multi-class tumors is compared. Results show that the error rate of the new method is obviously lower than the other two methods in most cases.

Finite n-Normalizer Groups

LIU Yanjun,ZHU Yixin

2009, 45(1):  6-10. 

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Based on Ashrafi's idea,n-normalizer groups are defined and investigated.First,some elementary properties about n-normalizer groups are given.Secondly,the existence of finite n-normalizer groups for every positive integer n are proved.Thirdly,the nilpotency and derived lengths of 2,3-normalizer groups are investigated. In particular,it is shown that G″=1 if # Norm(G)=2, and G?=1 if # Norm (G)=3 and G has abelian Sylow 2-subgroups.

On the Monotonicity of Autocorrelation Function for Finite State Markov Processes

CHEN Yong

2009, 45(1):  11-14. 

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By using the Jordan decomposition of the generator (transition rate matrix), the difference in terms of the autocorrelation function between the reversibility and the irreversibility is shown. For a finite state Markov process with continuous time, its irreversibility implies that there exists an observable function on its state space such that its autocorrelation function is nonmonotonic over ［0,∞) and negative at certain time interval; its reversibility implies that all the autocorrelation functions are monotonic and positive over ［0，∞).

An Arbitration Approach of Efficient BandwidthAllocation and Low Latency for SoC Communication

LU Junlin,LIU Dan,TONG Dong,CHENG Xu

2009, 45(1):  20-28. 

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A novel arbitration approach for SoC communication is presented. It provides fine-grained bandwidth allocation which is based on dynamically updated records of communication status. The arbiters in NoC routers, multi-port DRAM controllers and shared buses can adopt this approach to improve system performance. This proposed approach is evaluated with a metric called bandwidth shortage, which reflects the closeness of the actual bandwidth allocation to an optimal one. Experimental results reveal that this arbitration approach can reduce the bandwidth shortage decreases by 13%, and shorten the communication latency by 37.5%. Furthermore, the results of hardware implementation show that it is efficient in area and timing for large-and medium-scale SoC designs.

Clock Skew Scheduling for Area Optimization

WANG Kui,DONG Haiying,CHENG Xu

2009, 45(1):  29-34. 

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A new clock skew scheduling algorithm is proposed. This algorithm generates timing constraints which can effectively promote the area optimization of logic synthesis. During clock skew scheduling, the slacks are not equally assigned to the arcs in critical cycles. In stead, they are assigned according to the arc weights which are calculated considering the area impact of the corresponding paths. Experiment results show that this approach can efficiently reduce area of logic synthesis results compared with the traditional clock skew scheduling algorithm, without degrading the performance.

Numerical Simulation of Three-Dimensional Pulsatile Flow after Coil Embolization of a Lateral Aneurysm with a Straight Parent Vessel

WEN Gongbi,CAI Qingdong,LIU Aihua,WU Zhongxue

2009, 45(1):  15-19. 

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Blood flow characteristics which are affected by the locations of coil for partially blocked aneurysm for a lateral aneurysm with a straight parent vessel is numerically simulated in order to find the coil locations effective for aneurysm embolization. Supposing blood incompressible，viscous，Newtonian flow, non-elasticity of the wall, three-dimensional N-S equations are solved using artificial compressibility algorithm at pulsatile conditions. The maximum /minimum Reynolds number is set at about 475/152 based on diameter of parent vessel. The Womersley number is set to 2.5. These values are representative of the middle cerebral arteries in vivo data. The velocity, pressure field, mean wall shear stress on the aneurysm and inflow rate are calculated. The results show that velocity, pressure in aneurysm sac, mean shear stress on the aneurysm and inflow rate reduce greatly in the blocked model as compared to the non-blocked model. Inflow rate and mean wall shear stress in the neck blocked models are much lower than that in the dome blocked model and the lowest in the proximal neck blocked model. Since lower wall shear stress and smaller inflow provide hemodynamic environment promoting blood cloting, proximal or distal neck should be the effective coil location for a giant aneurysm embolization.

Capacitor-Less Fast-Response LDO for SoC Applications

SHEN Liangguo,ZHANG Xing,ZHAO Yuanfu

2009, 45(1):  35-41. 

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A low-dropout (LDO) voltage regulator with on-chip output capacitor for SoC applications is presented. The right-half-plane (RHP) zero generated by the gate-drain parasitic capacitance of the LDO pass element can be removed by a novel bi-directional asymmetric buffer (BDAB). This RHP zero removal scheme can enhance the stability, increase the unit-gain frequency (UGF) and improve the transient response performance. Post-layout simulation results of the proposed LDO show that the phase margin is better than 55°, the UGF is up to 1.7 MHz, while the overshoot and undershoot of the output voltages are less than 100 mV when the load current changes at a rate of 50 mA/μs.

The Wide-Band Scattering Characteristics Analysis of Satellite Targets in Different Space Attitude Conditions

ZENG Rui,ZHOU Ｌezhu,LI Mingzhi,WANG Wei

2009, 45(1):  42-48. 

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Wide-band scattering characteristics of typical spin stabilized satellite and triaxial stabilized satellite are computed by using finite-difference time-domain (FDTD). Compacts of the attitudes on scattering properties are investigated. The scattering properties of typical satellite targets in frequency domain are compared with the scattering properties in time domain. The results show that the satellite scattering properties in frequency domain are propitious to get the large-scale attitude information and the properties in time domain are propitious to get the small-scale attitude information. In addition, the change of rolling attitude more easily arouses the variety of scattering characteristics of typical satellite target than pitch attitude change does. The conclusions are valuable to the attitude identification of satellite and the design of ground based wide-band radar.

A Front-End ASIC for Semiconductor Radiation Detectors with Pile-up Rejection Capability

ZHANG Yacong,CHEN Zhongjian,LU Wengao,JI Lijiu,ZHAO Baoying

2009, 45(1):  54-58. 

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A CMOS front-end ASIC for semiconductor radiation detectors is proposed. The ASIC comprises a charge sensitive amplifier (CSA), a gm-C type shaper, a peak detect and hold circuit (PDH), and two discriminators. The PDH and the discriminators, together with some logic circuits, provide the capability to reject trailing edge pile-up. The circuit has been designed in a 0.5μm DPTM CMOS technology and verified by simulation. The most noise-sensitive blocks, the CSA and the shaper, have been manufactured and measured. The simulation and measurement results show that the ASIC is capable of pile-up rejection.

Petrogenesis of the Late Paleozoic Diorites-Granitoids in Fengshan Area, Northern Hebei Province: Constraints from Petrochemistry, Zircon U-Pb Chronology and Hf Isotope

FENG Yonggang,LIU Shuwen,L? Yongjun,TIAN Wei,LIU Xiaoming

2009, 45(1):  59-70. 

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The late Paleozoic diorites-granitoids emplaced into Precambrian lithological assembleges in Fengshan area, Northern Hebei province are characterized by enrichment in sodium (Na_2O/K_2O>1.0), high Sr, low Y and HREE contents, and their Sr/Y values change from 37.15 to 151.22. Most samples also show positive Eu anomalies and their Eu^* ranges from 0.92 to 1.53. LA-ICP-MS zircon dating and zircon Hf isotope analyses for samples diorite (sample JB6024) and monzogranite (sample JB6037-1) reveal that the diorite and the monzogranite were produced at 315±2.8Ma and 306.6±6Ma, respectively, namely, indicated the two late Paleozoic magmatic episodes in the Fengshan area. Whole rock petrochemistry, Sr-Nd isotopes and zircon Hf isotope indicate that the late Paleozoic Fengshan diorite was produced by the magmatic mixing between mafic magma derived from an EMI-type enriched mantle and felsic magma derived from partial melting of the ancient lower crust, and the granitoids derived from fractional crystallization of the dioritic magma that was obviously contaminated by upper crustal materials during their emplacement.

Study on Paleogene Alluvial Fan at Liujing, Guangxi Province, South China

LIU Jiang,BAI Zhiqiang

2009, 45(1):  97-103. 

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In comparison with the modern and ancient alluvial fan analogues, the matrix-supported carbonatite boulders and pebbles discretely cropping out to the northeast of Liujing town in Guangxi province, where they unconformably overlie the Lower Devonian Moding and Najiao formations, were described and studied. These discrete red coarse deposits represent the remains of different parts of one Paleogene alluvial fan respectively rather than isolated Devonian collapse in carbonatite cave or other depositions presumed by some related scholars. Based on the causer analysis, the Paleogene alluvial fan is proposed as piedmont alluvial fan sourced by the carbonate hinterland under a dry climate.

Analysis on Correlation and Concentration Variation of Atmospheric PAN and PPN in Beijing

YANG Guang,ZHANG Jianbo,WANG Bin

2009, 45(1):  144-150. 

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The concentrations of atmospheric PAN and PPN were measured by online instrument in Beijing from Aug.15 to Sep.12, 2006, and the correlation and concentration variation of PANs were analyzed. The results show that there was a high concentration of PAN and PPN in urban and rural atmosphere in Beijing. The highest concentrations of PAN and PPN were 11219×10^-12 and 1953×10^-12 L/L respectively at Zhongguancun site and 2505×10^-12 and 413×10^-12 L/L at Yufa site. PAN had a good correlation with PPN, also correlated with O_3. Thermal decomposition of PAN (TDPAN) accounted for 10%-70% of the total PAN (the measured PAN+TDPAN).

Electron Spin Resonance Dating and Strike-Slip Characteristics of the Daquan Fault in the Beishan Area on the Border between Xingjiang and Gansu Provinces

ZHANG Yu,PAN Jinhua,LIU Chang,GUO Zhaojie

2009, 45(1):  71-78. 

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The left lateral characteristics of Daquan fault was confirmed by: 1) remote sense images of the left-distortional drainage system; 2) statistics of scratches on the fault plane and cleavages in the fault zone; 3) micro-characteristics of fault rocks. ESR age of fault gouge indicated the fault movement occurred in early Pleistocene (1.2-1.5 Ma), whereas the branch faults movement occurred in ca. 300 ka. These data support that the formation of Daquan fault is closely related to the uplift process of Tibet, meanwhile it is also a long-distance effect of the continuous collision between Indian and Eurasia Plate and the uplift of Tibet during late Cenozoic.

Tectonic and Environmental Evolution of Gyirong Basin, and its Relationship to the Uplift of Tibetan Plateau

WANG Dechao,ZHANG Jinjiang,YANG Xiongying,QI Guowei

2009, 45(1):  79-89. 

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The Gyirong faulted basin, located in the northern slope of Himalayas, received over 300m thick sediments of lacustrine and fluvial facies scince late Miocene to early Pleistocene. Based on the analyses of the sedimentology, carbon-oxygen isotope and basin-controlling structures, integrated with previous studies of paleontology and palynology, this paper gave reconstructions on the controlling structures, sedimentary environment, climate changes and the evolutionary processes of this basin in the late Cenozoic. The coupling relationship between tectonic evolution and climate changes was also discussed. This study shows that the Gyirong basin underwent a evolution successively from a half-closed faulted lake basin in the early stage，to an open lake basin in the middle stage, and to a closed lake basin in the final stage.

Structural Characteristics and Geological Significance of Karayulgun Fault in Northern Tarim Basin

HE Dian,LI Jianghai,LI Baishou

2009, 45(1):  90-96. 

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Karayulgun fault located in Northern Tarim Basin is one of northwest-trending faults of Northern Tarim Basin. Based on field investigation and interpretation of seismic profiles, it is found that Karayulgun fault is a right-lateral strike-slip fault accompanied with North-Ka, Mid-Ka, and South-Ka en echelon folds and secondary faults that are consistent with classical theoretical model of strike-slip fault. Karayulgun fault belt developed on the basis of NW-trending reverse faults in Paleozoic, which experienced compression in Paleozoic, calm sedimentation in Mesozoic, and compression and strike-slip movement in Cenozoic. The location between Wushi-Wensu and Kuqa-Tabei units makes the fault regulate the differential deformation of the two regions. The fault and associated structures provide a favorable condition for hydrocarbon migration and accumulation.

Triggering Factors Susceptibility of Earthquake-Induced Landslides in 1976 Longling Earthquake

CHEN Xiaoli,RAN Hongliu,QI Shengwen

2009, 45(1):  104-110. 

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Based on GIS, the susceptibility of earthquake-induced landslide triggering factors of Longling Earthquake in 1976 is analyzed by means of the slope certainty factors (CF). The factors contributing the landslide occurrence include lithology, faults，earthquake intensity, epicenter distance, slope angle，slope aspect, elevation，river etc．The results show that different factor contribution to landslide is due to its value, and the most numerical intervals of each factor which are inclined to landslides are determined. This work is the basement for further study of earthquake-induced landslide susceptibility analysis.

Constructing Three-Dimensional Geological StructureModel of Cenozoic Erathem in Beijing

MING Jing,PAN Mao,QU Honggang,LIU Xueqing,GUO Gaoxuan,WU Zixing

2009, 45(1):  111-119. 

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To solve the increasingly outstanding urban geological problems and help researchers with visual analysis to urban geological survey data, three-dimensional geological structure model of Cenozoic erathem in Beijing was constructed for the first time. Due to the difference of precision in source data, the Cenozoic model was divided into two parts to be constructed respectively. Quaternary, the first part, was constructed via a former algorithm, the three-dimensional geological multi-body modeling algorithm from netlike cross-sections with topology. The stretching strategy was utilized to improve the solution of the algorithm to multivalue problem. Paleogene and Neogene, the second part, were modeled by using vertical addition of DEM. The constructed model deepened the cognition of geological researchers to the Cenozoic geological setting in Beijing. It also provided data support to the increase of exploiting efficiency of underground water and the rationalization of engineering planning.

Construction and Application of 3D Engineering Investigation Information System

CONG Weiqing,CHEN Lei,PAN Mao ,SUN Zhidong,ZHAO Guiqing,ZHANG Fang,TIAN Tian

2009, 45(1):  120-128. 

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A set of three-dimensional engineering investigation information system was built based on the practical engineering investigation application need and preliminary work. The system was composed by two major parts, two-dimensional subsystem and three-dimensional modeling subsystem.Many functions were achieved such as the fast flexible 3D construction of geological interfaces, internal attributes of geological bodies and engineering structures. And the data conversion interfaces to other calculation and simulation analysis software were also provided. Through practical test the system proved efficient during the engineering investigation.

Spatio-Temporal Variation of Landscape Patterns during Rapid Urbanization in Guangzhou City

GUO Luo,DU Shihong ,XUE Dayuan,JIANG Xueding

2009, 45(1):  129-136. 

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Using 3S technique, surveying and statistical analysis, this study took landscape pattern changes of Guangzhou City as a case study. The study examined the relationship between the process of a typical rapid urbanization and landscape spatio-temporal patterns during the period from 1985 to 2005, and compared the landscape and class-level pattern indices in Guangzhou City. The results show that the complexity of landscape structure and the fragmentation of the landscape increase from 1985 to 2005, whereas, the intensity and tendency of the landscape changes varied during the four comparative periods: 1985-1990, 1990-1995, 1995-2000, and 2000-2005. It is a rapid development period from 1985 to 2005 in Guangzhou. Spatio-temporal landscape patterns of the ten districts are different due to different development and planning motives. The intensity and extent of disturbance is strong and happen frequently in Urban, Panyu and Huadu districts. Conghua and Zengcheng districts represent slight disturbance, and their urbanization process mainly take place during 1990-2000. Urbanization in urban begin early while it mainly happens after 1990 in Panyu and Huadu districts ,showing the effect of frequent disturbance and severe intensity. The trend of urbanization in urban is similar to total study zone, showing frequent disturbance, multi-period and characteristics of long-term urbanization.

Land Surface Temperature Anomalies and Monitoring through Thermal Remote Sensing： A Case of Coal Bed Methane Area at Jiaozuo， Henan Province

NAN Peng,QIN Qiming,YAO Yunjun

2009, 45(1):  137-143. 

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Based on the analysis of land surface energy-radiation balance theory, the process of underground heat conduction is analyzed from aspects of rock/soil heat conduction capability and influence over rock thermal conductivity caused by coal-bed methane (CBM). The reasons of land surface temperature (LST) anomalies caused by the heat conduction from the depth of earth are discussed. LST at coal bed methane district is retrieved based on the ASTER data acquired over high CBM density area of Jiaozuo, Henan Province. The retrieved steps is as following: Firstly the atmosphere transmittance is simulated through MODTRAN 4 and land surface emissivity is calculated from NDVI. Then LST of study area is retrieved through split-window algorithm. The result demonstrates that the maximum LST is 302.67Ｋ and the minimum is 296.62Ｋ. LST anomalies can be easily identified in some area. The causes of LST anomalies area are analyzed and it can be deduced that the main reason of LST anomalies of study area is underground thermal conductivity anomalies caused by high CBM density. The conclusion needs further verification through other methods.

Evaluating the Ecological Service Function of Soil Conservation Based on RUSLE and GIS

GAO Jiangbo,ZHOU Qiaofu,CHANG Qing,LI Shuangcheng

2009, 45(1):  151-157. 

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Under the support of GIS technique, the authors evaluated the capital stocks of the ecosystem's soil conservation with a case study in Beijing, Tianjin and Hebei Province. On the basis of the data of daily rainfall, NDVI, DEM, LUCC, and soil types of the study area, according to the Revised Universal Soil Loss Equation, the maximum amount of potential soil erosion and its actual quantities were calculated. The deviation between them was the conserved amount, which was converted into capital stocks with the methods of Shadow Price and Market Price. The result show that the value of the soil conservation in the study area was about 176.832 billion RMB yuan, which approximately equaled to the 21.41 percent of the total GDP in 2000, of which the preserved nutrient was about 167.797 billion RMB yuan and the alluvial bedload was 9.035 billion RMB yuan respectively. The contributing percent of individual ecosystems was as follows: the forest occupies 44.34%, cropland 44.91%, grassland and water 10.75%.

Study on Net Primary Production Variations in the Central Part of Inner-Mongolia during 1981-2000

WANG Jun,MENG Jijun

2009, 45(1):  158-164. 

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Based on AVHRR GLOPEM NPP dataset and climate data in the corresponding period, the authors analyzed the situation of the net primary production degradation in the central part of Inner-Mongolia and its correlation relationship with climate change during 1981-2000. The results show that: 1) from the eastern to the western part, the spatial distribution of net primary production had a descending tendency, and the inter-annual variation of net primary production in the whole area was apparent, especially during 1990-2000, and the variation rate could be due to 10.32gC/m²?a; 2) the inter-annual variation of net primary production had apparent spatial differentiation; 3) correlation coefficients between inter-annual variation of net primary production and inter-annual variations of climate factors had apparent spatial differentiations; 4) various vegetation types had various responses to climate change, and the inter-annual variation of precipitation had more significant impact on vegetation dynamics than the inter-annual variation of temperature in the study area. This study displays the situation of the net primary production degradation in the central part of Inner-Mongolia and the correlation ralationship between climate change and the net primary production degradation. Moreover, it will provide scientific references for the restoration and reconstruction of the degraded vegetation.

Analysis and Simulation of Cultivated Land Conversion and Distribution in Beijing Mountainous Areas Based on GIS and Logistic Regression Model

ZENG Lingyun,WANG Jun,WANG Hongya

2009, 45(1):  165-170. 

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Taking Beijing mountainous areas as a study case, this paper analyzes and simulates the cultivated land change between 1996 and 2004 using ARCGIS and Logistic regression model with the data of land use map, DEM, population, GDP, and so on. The results show that: 1) during the year of 1996-2004, one third of cultivated land lost and mainly transited to built-up land and forest land; 2) by spatial Logistic regression, sople, elevation, GDP density, population density, and distance to the nearest road were the most influential factors in controling cultivated land distribution in the Beijing mountainous areas; 3) the total correction percentage of the results simulated by the spatial Logistic regression model was 78%, the correction percentage of cultivated land was 70%, and the non-cultivated land was 79%.

Analysis to Temporal Characteristics of Tourist Flows on Jiuzhaigou World Natural Heritage

YAN Lei,XU Xuegong,ZHANG Xiaoping

2009, 45(1):  171-177. 

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This paper introduces the wavelet tool and 4 indexes to quantify the temporal characteristics of tourist flows. Based on the monthly visitor data from 1994-2006 and daily visitor data from 2003-2006 which were mainly collected through JDS (Jiuzhaigou digital system), the multi-time scales characteristics of tourist flow along the time series were analyzed by using the morlet wavelet transform. The complex structure of multi-time scales are exhibited, also, the periodic oscillation and the main periods of tourist flows at different scales are identified through Wavelet Toolbox in MATALAB 7.3. The results show that 1) during 1994-2006, the number of tourists increased rapidly in the way of cubic function and curve of tourists had apparently 3 peaks in July-August, October, and May respectively; 2) at the month scale, the trend of tourist fluctuation decreased overtime; 3) in the past 13 years, there was an approximately 1 year period in the tourist time series. Furthermore, 50-70 days was another period in 2003-2006. After applying wavelet tool to analysis tourist flows, this article argues that the localization characteristics of time-frequency for wavelet analysis can effectively demonstrate the detailed structures of tourist flows. Wavelet is a promising method to analyze temporal characteristics of tourist flows, and the findings can provide a scientific guideline for adjusting and controlling tourist flows.

Preliminary Analysis on Algal Inhibition by Rice Straw Extract and Allelopathic Components

ZHU Qing,FENG Jing,WU Weizhong,RUI Kejian,GAO Hang

2009, 45(1):  178-182. 

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A laboratory study was conducted to investigate the inhibitory components in the rice straw extracts under different degradation manners and time, and their corresponding effects on algae inhibition. It was found that there were algae inhibitory chemicals in rice straw. The inhabitation ratio of rice straw extract to Microcystis was 69.3% when stored at a low temperature of -4℃ for 4 days with a concentration of 2.5g/L. Both anaerobic and aerobic decomposing rice straw extract can be useful for algal inhibition. If stored for 15 days with the concentration of 1.5g/L under anaerobic and aerobic conditions, the inhabitation ratio of rice straw to Microcystis was 83% and 81% respectively. The allelopathic substances were analyzed by using GC-MS, and then the possible mechanism was proposed. The results show that the allelopathic components in the rice straw extracts were mainly naphthylamine, esters and phenols, typically phthalic acid esters (PAEs). The allelppathic components and their concentration in the rice straw extracts decreased along with the straw decomposition time, especially for aerobically decomposed extract. There was a good relationship between the inhibitory effects and the allelppathic components in the rice straw extracts.