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The jack-up rig is the most widely applied mobile platform in the shallow-water offshore drilling. Since several predetermined target wells are in the soil stratum of sand overlying clay, the punch-through accidents occur frequently during the jack-up rig spudcan penetration leading to disastrous consequences and sometimes even casualties. Although a few centrifugal model experiments and indoor large-scale experiments have been conducted to simulate the spudcan penetration, these experiments expose significant knowledge gaps that deviate from the actual field operations due to the limitations of a constant displacement speed plan instead of multi-stage preloading plan. In this study, seventeen (17) field experiments simulating spudcan installation in sand overlying clay in in-situ soil strata in the intertidal sea of the Bohai Bay are reported to address the knowledge gaps. A systematic study of the spudcan penetration is presented through key influencing factors such as soil strength ratio of upper sand to lower clay, geometric ratio of spudcan diameter to upper sand thickness, ballasting speed and holding period time. Results indicate that the ultimate (peak) soil bearing capacity increases almost quadratically with the increase in strength ratio of upper sand to lower clay; the final spudcan penetration resistance decreases as a power law relationship with the increase in geometric ratio of spudcan diameter to upper sand thickness; the instantaneous spudcan penetration velocity increases as a logarithmic function with the increase in ballasting speed and the pore water pressure decreases as an exponential function with the increase in holding period time. From these experiments, three novel schemes are proposed to prevent the punch-through. Lastly, this study provides a design basis and theoretical guidance for precise calculations of the ultimate bearing capacity, accurate analysis of punch-through risk and effective prevention of the punch-through accidents in the real jack-up rig.

The number of visible satellites has significantly increased, which provides a possibility for high-precision positioning of global navigation satellite systems (GNSSs). However, GNSS receivers with higher computing power will be required owing to the usage of a large number of visible satellites, and selection of partial satellites with better spatial geometry is required for obtaining high positioning precision schemes for a variety of applications. The geometric dilution of precision (GDOP) is related to the geometrical arrangement of the user and the satellites and computationally intensive, involving matrix multiplication and inversion operations. Various intelligent algorithms for satellite selection have been suggested recently, such as genetic algorithms (GAs). the computation number of GDOP was reduced, owing to the adoption and optimization of these algorithms. However, the algorithms suffer from two issues: 1) the computation process is complex, and significant parametric tuning is required. 2) the algorithms may fall into local optima, instead of the global optimum, owing to the stochasticity of the optimization process. In the paper, we have proposed a novel algorithm for satellite selection, based on chaotic particle swarm optimization (CPSO), which has the advantages of faster convergence, a smaller number of adjustable parameters, and stronger adaptability, compared with the existing algorithms. Firstly, the visible satellites received by the GNSS receiver are continuously encoded and randomly grouped, form the initial population. Afterward, the positions of the particles are updated by the PSO’s velocitydisplacement model. Finally, the CPSO-based algorithm for selection of satellites is designed to replace poor-performing particles with particles in the initial population, which helps to effectively avoid sub-optimal solutions. The proposed algorithm was compared with the traversal method. The simulation results demonstrated that if more than five satellites are selected, the satellite selection time amounts to 37.5% of the time required by the traversal method, and the GDOP error is in the 0.7 range. The proposed algorithm was further validated on the BDS/GPS integrated navigation satellite selection, suggesting the effectiveness of the application in the multiple GNSSs integrated navigation.

High-pressure and high-temperature (HPHT) deepwater oil and gas wells are under the influence of high-temperature formation fluid after putting into production. The thermal expansion pressure of sealed annular fluids caused by the annulus temperature change has large effect on the safety of strings among dual packers. This study presented a casing-cement sheath-formation model which take into account the effect of the sealed annulus temperature and volume changes between dual packers, established a displacement function of the sealed annular fluid, the free tubing and the cemented casing that based on the thermo-elastic mechanics, analysed the influence factors of sealed annular pressure, including the expansion coefficient and elasticity modulus of annular fluid, the wall thickness of casing and tubing stings. An example of a HPHT deepwater gas well was analysed. The results show that the sealed annular pressure has a positive linear correlation with the annulus temperature difference, and annular pressure buildup with the increase of thermal expansion coefficient and elasticity modulus of the annulus fluid, decreases with the casing wall thickness. To prevent the potential risk associated with annular pressure, high-compressibility and thermal-insulated materials could be developed to control sealed annulus thermal expansion pressure.

The plant species diversity of stands converted from croplands as affected by revegetation approaches and terrains was studied using the transect line plot sampling. The goal of the study was to provide reference for evaluation reforestation effects and forest management in the Loess region of western Shanxi Province. The results showed that revegetation approach had a great influence on plant species diversity in stands. The number of species in the natural restoration forest (NF) was 1.6 times of that of Robinia pseudoacacia plantation (RP), the Shannon index of NF was higher, and the Pielou index of NF was lower. Slope position had significant effect on the species diversity, and the three species diversity indices were all in order of bottom of loess gullymiddle slope of loess gullyslope of loess hilltop of loess hill. The species diversity indices on the shady slope were higher than those on the sunny slope, while the difference was not significant. Integrated effects of terrain and revegetation approach had significant influences on species diversity. The species diversity was highest at the bottom of shady slope of NF, and the species evenness was highest at the bottom of shady slope of RP. For improving the species diversity, the afforestation design in the Loess area must consider terrain position and the natural forest recovery process following the principle of 'selecting suitable tree species for the right site'.运用样带样方调查法,对比不同恢复方式和地形条件下退耕林分的物种多样性,以期为晋西黄土区植被恢复效果评价和经营管理提供参考.结果表明: 恢复方式对退耕林分物种多样性具有显著影响.自然恢复林物种数为刺槐人工林的 1.6倍,Shannon 指数大于刺槐人工林,Pielou 指数小于刺槐人工林.物种多样性受坡位影响显著,各指数均表现为沟底沟坡梁峁坡梁峁顶;坡向对退耕林分物种多样性影响不显著,各指数均表现为阴坡阳坡.物种多样性受地形和恢复方式综合作用影响显著,在自然恢复林阴坡沟底处最高,物种均匀度在刺槐人工林阴坡沟底处最高.从提高物种多样性角度,黄土区植被恢复在遵循适地适树原则的同时,应参照自然恢复林分,在不同地形部位采用不同的造林设计.

Vegetation types restrict soil structure and heterogeneous processes of elements, which result in difference in spatial distribution of soil nutrients. In this study, the differences in contents of soil nutrients, TN, TP, TK, and soil organic matter (SOM) among different vegetation types were analyzed, and the accuracy of ordinary kriging, regression model and regression model based on vegetation type in predicting soil nutrients was compared. The results showed that, TN, TK and SOM were significantly (P0.05) correlated to vegetation type, and TP had no significant correlation with vegetation type (P=0.390). TN and SOM had significant difference between shrubbery and arable land. TK had significant difference between arbor and scrub-grassland, shrubbery and arable land, and scrub-grassland and arable land, respectively. In a non-continuous typical small karst catchment, because of high spatial heterogeneity of terrain, the accuracy of multivariate linear regression model based on the real terrain factors of various points was considerably higher than that of ordinary kriging prediction method considering the locations of the known points and prediction points. Moreover, the regression model based on vegetation type improved the prediction accuracy of the TN.植被类型制约着土壤结构和元素的异质化过程,致使土壤养分空间分布存在差异性.本文研究了典型喀斯特小流域不同植被类型间土壤养分(全氮TN、全磷TP、全钾TK、有机质SOM)含量分布的差异性,分析比较了普通克里金、回归模型、基于植被类型的回归模型对土壤养分预测的精度.结果表明: TN、TK、SOM与植被类型显著相关(

Water use strategy in growing seasons plays a great role in the management of riparian poplar plantations in northern China. The research was conducted on a poplar (Populus × euramericana cv. '74/76') plantation located near the floodplain of Chaobai River in the northeastern su-burb of Beijing. The influencing factors of poplar sap flow (SF) were presented based on the measurements on the stem SF with thermal dissipation sap flow probe (TDP), soil volumetric water content (VWC) with time-domain-reflectometer (TDR) and environmental factors with eddy cova-riance system from June to July, 2014, to explore the impact of shallow ground water on SF. The results showed that the diurnal variation of SF presented single or double peaks depending on the varia-tion of solar radiation (R). The SF density decreased in soil water relative deficient period (RDP), and the peak time advanced to 12:30 from 14:00, while the time lag between the SF density and R showed no obvious change. The solar radiation and air vapor pressure deficit were the predominant factors of SF during soil water relative sufficient period (RSP), while soil water became the limiting factor in RDP. During the RDP, the daily water consumption of individual poplar tree was significantly negatively correlated with soil VWC at the depth of 100 cm, and significantly positively correlated with soil VWC of the other depths. The shallow ground water (at the depth of ≥150 cm where the soil water content showed little change) might move to the upper soil layer controlled by the capillary force and supply for poplar growth during the soil water-relatively deficient period.华北地区河岸杨树林生长季的用水特征对杨树人工林经营管理具有重要意义.本文以北京市潮白河畔的杨树人工林为研究对象,采用热扩散式探针(TDP)测定树干液流、管式TDR土壤含水量法测定土壤体积含水量、开路涡度相关系统测定环境因子数据,对2014年6—7月的杨树树干液流及其影响因素进行系统研究,以探究浅层地下水对树干液流的可能影响.结果表明: 杨树树干液流日变化随太阳辐射呈现单峰或双峰变化,在土壤水分相对亏缺时,杨树树干液流密度明显减小,达到峰值的时间从14:00提前到12:30,但树干液流对太阳辐射的时滞效应没有明显变化.在表层土壤水分相对充足时,太阳辐射和空气饱和水汽压差是杨树树干液流变化的主导因子,但在表层土壤水分亏缺时,土壤水会成为杨树树干液流的限制因子;当表层土壤水分相对亏缺时,杨树单株耗水与100 cm土层土壤体积含水量呈显著负相关,与其余各土层体积含水量呈显著正相关.浅层地下水(相对稳定的150 cm及更深处)在土壤表层土壤水分含量相对亏缺时,可在毛管力作用下对上层土壤水进行补充,供给杨树生长需要.

Based on the Forest Ecosystem Services Assessment Standards (LY/T 1721－2008) issued by the State Forestry Administration, this paper evaluated four key functions of forest ecosystems, i.e., water conservation, soil conservation, carbon fixation and oxygen release, and nutrient accumulation. Focusing on the project area of Majiang County in Guizhou Province, this study provided some quantitative evidence that the implementation of the small hydropower substituting fuel project had positive effects on the values and material quantities of ecosystem service functions. The results showed that the small hydropower substituting fuel project had a significant effect on the increase of forest ecosystem services. Water conservation quantity of Pinus massoniana and Cupressus funebris plantations inside project area was 20662.04 m根据国家林业局发布的《森林生态系统服务功能评估规范》(LY/T 1721—2008),从涵养水源、保育土壤、固碳释氧和积累营养物质功能4个方面进行评价,研究小水电代燃料工程的实施对贵州省麻江县项目区森林生态服务功能的物质量及其价值的影响.结果表明: 小水电代燃料工程对森林生态系统服务功能物质量的增加有显著作用.马尾松和柏木人工林在项目区内涵养水源功能的物质量达20662.04 m

This paper presents a new technique of deep sea image mosaic based on SIFT(Scale-invariant feature transform) algorithm. The SIFT algorithm by means of the median filter to the noise processing and itself has a good ability to resist scale changes, It can effectively match the characteristics of the two deep-sea biological images in the case of parallax. In the same coordinate system, the corresponding coordinate transformation is made according to the matching characteristic points. And the neighborhood average algorithm is used to optimize the processing. The whole process of using MATLAB to achieve, The program interface is simplified to enter two images.

The proposed intelligent method, which is based on the pressure data and the spatial location of the adjacent drilled wells, and the spatial continuity of the targeted region, is able to establish the formation pressure profile with credibility, the safe window with credibility of drilling fluid density, the probability profile of drilling risk and the risk interval of drilling operation. As a result, the proposed method achieves the intelligent identification of drilling risk in complex formations. In this intelligent method, the concept of formation pressure matrix is introduced firstly, and an epitaxial stratigraphic pressure migration algorithm is established to calculate the pressure of the targeted wells in the same tectonic region based on the depth adjustment and the inverse distance weighting algorithm. Secondly, the probability of drilling risk is calculated. Thirdly, the membership function of different degree interval is constructed by fuzzy mathematics theory combining with the accident record of drilled wells; and finally, divide the membership degree of drilling operation risk to achieve the intelligent identification of drilling risk. The intelligent method has been successfully applied in BD gas field in Indonesia. Nine drilling accidents such as kicks, collapses, leakages and stickings have been accurately identified in a certain well. The formation pressure of adjacent drilled wells is transplanted to the targeted wells and the pressure prediction is more accurate. Meanwhile, combined with the accident records of drilled wells, the intelligent identification of drilling risk can be carried out. The two issues mentioned above have been the focus of researchers. Under normal circumstances, the designers use stratigraphic comparison method, in which the formation pressure of the drilled wells is directly applied to the targeted well and does not consider the spatial distribution characteristics of the targeted formation. And the designers cannot intuitively determine the possibility of drilling risk according to the numerical drilling risk probability value. This intelligent method gives the transplantation method calculating the formation pressure of the targeted well in the same tectonic region and divides the drilling risk interval. This method has been used to analyze the risks in BD gas field in Indonesia and the LW oil field in South China Sea. Case studies were carried out to verify the method, in which the predicted formation pressure was compared with that derived from the LWD. The results showed that the maximum relative errors were within 2.76%. Example analysis showed that the identifying result of this method agreed with the actual engineering. The identification results of proposed intelligent method agrees with the engineering practical situation, satisfies the need of drilling engineering and can provide basis for identifying risk in drilling design.

The aim of the current study was to confirm the effect and elucidate the mechanism of bone marrow mesenchymal stem cells (BMSCs) in acute myocardial infarction (AMI). AMI was induced in mini‑swine by ligating the left anterior descending coronary artery, and BMSCs (1x107) were injected via a sterile microinjection into the ischemic area. Six months postoperatively, electrocardiograph‑gated single photon emission computed tomography revealed that the myocardial filling defect was reduced and the left ventricular ejection fraction was improved in the BMSC group compared with the control group (P

Background: Ischemic stroke is one of the most common causes of death worldwide. Early and accurate prediction of outcome in acute ischemic stroke (AIS) is important and influences risk-optimized therapeutic strategies. We investigated the changes in high-sensitivity C-reactive protein (Hs-CRP) and homocysteine (HCY) levels, two of the risk factors, during the acute period of AIS and evaluated the relationship between these levels and short-term prognosis. Methods: We prospectively studied 189 patients with AIS who were admitted within 24 hours after the onset of symptoms. Serum Hs-CRP, HCY levels, and National Institutes of Health Stroke Scale (NIHSS) were measured at the time of admission. Short-term functional outcome was measured by the modified Rankin scale (mRS), 90 days after admission. Results: The median serum Hs-CRP and HCY levels were significantly higher in AIS patients as compared to normal controls (P , 0.0001, respectively). High-sensitivity C-reactive protein and HCY were independent prognostic markers of functional outcome and death (adjusted for age and the NIHSS) in patients with AIS. In receiver operating characteristic curve analysis, the prognostic accuracy of the combined model (HCY and Hs-CRP) was higher compared to all measured biomarkers individually and the NIHSS score. Conclusion: High-sensitivity C-reactive protein and HCY are independent predictors of short-term outcome and mortality after AIS. The combined model may provide additional general prognostic information.

The aim of the present study was to investigate the protective effect of baicalin (BA) against ischemia-reperfusion (I/R) injury in isolated rat hearts. Sprague-Dawley rat hearts were rapidly removed, mounted on a Langendorff apparatus and subjected to 30 min ischemia followed by 30 min reperfusion with Krebs-Henseleit (K-H) solution at 37°C to establish the isolated I/R injury model. All animals (n=50) were randomly divided into five groups (n=10 in each): I, normal control; II, I/R; III, I/R plus 20 mg/kg BA; IV, I/R plus 40 mg/kg BA; and V, I/R plus 80 mg/kg BA. The degree of heart injury caused by the I/R was assessed by evaluating left ventricular function and by detecting the levels of lactate dehydrogenase (LDH) and creatine kinase (CK) in the coronary effluent and the myocardial superoxide dismutase (SOD) and malondialdehyde (MDA) levels in the isolated rat hearts. Myocardial infarct size and vascular density were assessed using histology and immunohistochemistry. The apoptotic cardiomyocytes were determined using flow cytometry (FCM). Compared with group II, the BA groups demonstrated improved left ventricular function, reduced CK and LDH release in the coronary effluent and increased SOD and MDA activity (P

A new measurement of surface reflection index distribution is introduced. Using walk-off induced by return laser pulse power variation, which usually should be eliminated in LADAR system, relative reflection index distribution of material surface could be deduced from the 3D point-cloud data. Detection of actual pulse waveform is the first step, and then the mapping of time walk-off and amplitude is obtained. According to this relationship, amplitude distribution could be deduced from the angle/angle/time data of LADAR. After detaching the influence of detect direction based on the ladar detection range function, the reflection index distribution is acquired finally. The experimental result of this method is shown in the last of paper.

In order to meet the needs of linear long distance wireless sensor network environment, a linear long distance wireless sensor network communication protocol is designed. In this paper, we design a architecture of "port number mapping method", analyze and study the discrete asymmetry of linear network energy consumption. Linear long distance frequency hopping algorithm for wireless sensor network is researched. Ultimately, we achieve a linear long-distance wireless sensor network system which can provide more applications.

This paper utilizes a new frequency hopping algorithm based on the long distance of wireless sensor network. Frequency hopping sequences will be controlled through the self-designed clock synchronization mode. By adding clock synchronous information within the network control commands, the energy consumption of clock synchronization can be reduced. We can control the frequency hopping sequences according to the design of frequency hopping sequences table. In complex interference environment, high quality communication will be guaranteed by using the adaptive frequency hopping and artificial intervention frequency hopping algorithm. This algorithm can greatly improve the integrity and reliability of wireless sensor network data transmission, which means long distance data transport will be more safety.

Lateral friction against surface conductor plays an important role in the stability of subsea wellhead. It changes during jetting process and increases with soaking time. But the change rule and mechanism remain unclear. Therefore, the purpose of this paper is to explore the change mechanism of lateral friction during and after conductor jetting process by field experiment and numerical simulation. Firstly, a field experiment was conducted to simulate actual surface conductor jetting process. The time- dependent change rule of radial pressure, pore water pressure and effective skeleton pressure were obtained. Then, the stress states of soil bodies during this process were analyzed. Based on experiment and analysis results, the primary reason that causes the change of lateral friction was found. After that, to explore the specific change features of bearing capacity of seabed soil for surface conductor, another field experiment was conducted. Finally, finite element method was adopted to simulate the conductor jetting process and to verify the research conclusions. The field simulation experiment showed that the sensor at the base of surface conductor suffers conspicuous higher value of radial pressure than other sensors above. Meanwhile, the effective pressure of each layer has a tendency of declining as time increasing and then gradually adds after reaching a certain value. These regularities matches the change rule of radial pressure on piles during driving process. Based on the stress analysis, it is certain that the soil compaction effect does exist in conductor jetting process, caused by which, the formation and dissipation of pore water pressure during jetting process would be highly related to the change of lateral resistance against surface conductor. After jetting into position, soil lateral friction would increase with time non-linearly. The change rate would gradually rise at the first 10 hours. After 72 hours, the added values of friction are small and the change rate turns to flat. According to the numerical modeling results, under the action of jetting force, on one hand, soil bodies that are closed to bit are cut into grains and flow out from wellbore with drilling fluid; on the other, soil bodies that are farther from bit would be squeezed down and then pushed around. Previous studies mainly considered the soaking time and bearing capacity of surface conductor, focused on specific values. This research designed a system to simulate surface conductor jetting process to explore the change mechanism of lateral friction against surface conductor by combining the method of numerical modeling and field experiment.

Top tension plays an important role in stability of riser system. Either excessive or insufficient value of it tends to cause negative effects on risers' proper function and then pose a threat on drilling operation. But there is no unified calculation method about the setting value of riser top tension. Therefore, the purpose of this paper is to establish a calculation method of riser top tension that both meets the requirements of theory and engineering. The improved method is based on the theory of effective axial force in tubing mechanics. It considers the requirement of risers stability and over-pull force to lower marine riser package (LMRP) in field drilling operation. Take three deepwater wells in South China Sea as examples. Utilizing finite element analysis software ANSYS to model the riser, subsea wellhead and conductor systems respectively, then exerting the calculated top tension and environment load, the analysis results can be used to check the accuracy of the proposed calculation method. After analyzing the related methods proposed by American Petroleum Institute[1] (API) and Institute of French Petroleum[2] (IFP), it is found that both of them have their limitations. The former one only concentrates on stability but ignores the over-pull force required by LMRP in field operation. The latter one takes the requirement of overpull into consideration though, it regards this force as effective tension rather than true tension. According to the related theories of tubing mechanics, the effects of true axial force and effective axial force on the riser mechanical behavior is analyzed. The results show that, the bottom tensile force to LMRP is determined by true axial force, and the risers' stability depends on effective axial force. Through the force analysis of risers which simultaneously bear the inside and outside pressure, the correspondent mechanical model was established, and a new calculation method of top tension was derived, which modifies the deficiencies of algorithms proposed by API and IFP. The accuracy of this method is verified by the values if field operating and numerical simulation of ANSYS. The novelty of this method is to propose a calculation method of riser top tension that could improve the deficiencies of API and IFP and meet the requirement of stability and bottom over-pull force to LMRP in field operation.

In order to solve the problems followed mechanical seal leakage of the side entering agitator in wangtan power plant limestone - gypsum FGD, a magnetic drive technology was introduced, compared the characteristics of mechanical transmission to the magnetic drive technology. Magnetic drive technology was used in the desulfurization side entering agitator, and it’s an effective solution to the desulfurization side entering agitator mechanical seal leakage problem, the effect is significant.

We experimentally demonstrate a tunable fiber ring laser with narrow linewidth and fine tuning resolution based on Er3+-doped fiber(EDF) laser material. A tunable fiber Bragg grating(FBG) filter is used in the system as the frequency selecting element, and a stepping motor together with a single chip acts as the precise tuning mechanism. The fiber ring laser has a narrow linewidth of ~0.07nm, a tuning resolution of ~1.5pm/pulse, an output power of ~25 mW, and a slope efficiency of ~17.9%.

As development of laser technology, the characteristic of laser atmospheric propagation is always hot spot in laser domain. Using theoretical models of laser atmospheric propagation, a simulation system is researched by implementing a scientific method of software development. This simulation system can simulate the radiate property of laser propagation in atmosphere, and demonstrate the course of laser propagation. This theoretical model of atmospheric propagation is based on Lambert-Beer law, combined with other classic theoretical model such as Rayleigh scattering and Mie scattering. Multiple scattering theories are used when simulating the laser propagation in smoke or fog. In calculation, the atmosphere is divided into layer. An appropriate model will be selected for calculation in each layer in order to enhance the stimulation precision. Lastly, the figure of light spot is drawn along with transmission space. Laser atmospheric propagation is demonstrated.

An aperiodic fiber grating with asymmetric reflection spectrum structure is studied, and its spectrum characteristics are described by an introduced parameter, the spectrum profile slope, which can measure the spectrum asymmetric property. Based on the fiber gratings with asymmetric reflection spectra, a new sort of tunable narrow band-pass fiber grating filter is designed as its application, whose characteristics, namely working wavelength, band width, and tunable range, are analyzed as well.

One kind of scanning distance-imaging system based on time-of-flight measurement is reported in this paper. With Nd:YAG Laser for light source, oscillating mirror for light beam scanning, SR620 for fly time measuring, the target tridimensional image is traced out through the software. This prototype has great distance-resolution as 15cm, angle-resolution as 1mrad ×1mrad, scan scale as 10×10°, and the detective range as 1km. The mathematical model of sampling, data mapping and coordinate transform are discussed, which used for system design. And the final range images are also given as follow

A novel ferrofluid-based microvalve adopting an electromagnetic actuation is presented. In the device, ferrofluid controlled by magnetic force is used as a microactuator. The deflection of the diaphragm caused by the ferrofluid-based actuator opens or closes the fluid flow in the microchannel. A detailed description of the design and working principle of the microvalve is presented. The driving force generated by the ferrofluid under applied magnetic field has been measured by a microforce sensor. And the deflection of the diaphragm has been simulated by ANSYS software.

In the case of two mismatches observed in alleged parent-offspring pairs, there is doubt as to whether there is an exclusion of the putative parent or the existence of two mutations. Here, we report on four cases with two mismatches in paternal/maternal duos based on capillary electrophoresis (CE) results. The analyzed next generation sequencing (NGS) results were compared with 20 autosomal STRs derived from previous CE-based analysis. In summary, the NGS samples used offered comprehensive information of different types of markers that can improve resolutions for paternal/maternal duos analysis.

Surface reconstruction and NURBS surface generation based on 3D surface mesh partitioning are more essential today. In this paper, we present a new method of automatic partitioning complex surface meshes into the bounded regions with four corner points (quadrilateral regions) based on using control points (notches) for NURBS surface generation. The procedure of this method consists of 4 major steps: (1) the 3D polygons mapping into 2D polygons; (2) convex decomposition of the polygons in the 2D space; (3) subdivision of each polygons into quadrilateral regions; (4) mapping the received 2D regions onto the 3D original surface mesh. Main contribution in this paper is automatic partitioning of the 3D segmented parts of complex surfaces into quadrilateral regions based on combination of segmentation, mapping, and subdivision techniques. Automatic partitioning allows us to create not rectangular but quadrilateral regions without using any user-dependent parameters for further NURBS surface generation.

The influence of vehicle platform deformation on the measuring errors of a theodolite was analyzed,then the platform deformation was divided into two types of translation and rotation.A numerical simulation was performed to demonstrate that the platform rotation deformation was the main factors to affect the measuring error of the platform.A simulation model of vehicle theodolite between measuring error and rotation deformation was established,and the influence of the target location and rotation deformation on measuring errors was simulated based on the model.Furthermore,the platform angular deviation was measured by a self-collimation measurement system based on Moire fringe and the platform angular rotation was measured by a inclinometer,which then was validated by experiments.Obtained data show that this method can effectively compensate static angle measuring errors come from the deformation of vehicle platform,and can improve the azimuth precision to 103.7″and elevation precision to 89.4″.It provides a theoretical reference and technical support for the high-precision measurement of vehicle theodolites.

An optical frequency shift keying (FSK) transmitter performed by the cross gain modulation (XGM) in a semiconductor optical amplifier (SOA) is used in an optical label switching (OLS) system with 622 Mbit/s FSK label and 10 Gbit/s amplitude shift keying (ASK) payload. The key parameters in this system are optimized to achieve the best performance of FSK/ASK signal, including the input power of LD, the extinction ratio (ER) of the control light and that of the ASK payload. Besides, the transmission performance of ASK payload and FSK label is also investigated after propagating in the 50 km single-mode fiber (SMF).

This work was aimed at preparing polypropylene grafted acrylic acid (PP-g-AA) with high grafted content and small gel percent by using a supercritical carbon dioxide (scCO2)-assisted solid-state free radical grafting process. The effects of various factors on both the grafted acrylic acid content and gel percent in PP-g-AA were investigated. Those factors included the reaction time, reaction temperature, CO2 pressure, monomer and initiator concentrations. Results showed that self-polymerization of acrylic acid resulted in crosslinking of PP chains and production of gel in PP-g-AA. There exists an optimal reaction time to produce PP-g-AA with high grafted content and small gel percent at a certain temperature. Both the initial AA/PP mass ratio and CO2 pressure constituted very sensitive process parameters that could control the gel percent and grafted content in PP-g-AA to a significant extent and with ease. The crystallization temperature, melting temperature and crystallinity increased with the increasing of the grafted content of PP-g-AA. Moreover, the PP-g-AA removal of gel has a higher thermal stability than the blank PP.

This paper reports that Nd2O3 nanoparticles modified by AOT(sodium bis(2-ethylhexyl) sulfosuccinate) were prepared using microemulsion method in the system of water and propanol/AOT/toluene. Transmission electron microscopy shows that the Nd2O3 nanoparticles take the shape of sphere with 18 nm and 31 nm with different preparation. The organic sol of Nd2O3 nanoparticles is very stable at room temperature. X-ray diffraction results show that the product has hexagonal phase structure. Two ultraviolet emission band at 344 nm and 361 nm corresponding to the transition of 4D3/2 → 4 I9/2 and 2P3 /2 →4 I11/2 or 4D3/2 → 4 I13/2 were observed.

3-D rotation interaction is an indispensable function of 3-D imaging system of laser scanning, therefore it is also a hot topic of 3-D interaction research. The drag of mouse can be reflected by the on-screen movement of the cursor however, when the dragged object is a 3-D object, the contradiction between it and the 2-D screen exposes. Aiming to resolve this problem, we establish a new rotation algorithm basing on quaternion, called the “arcball”, which we will elaborate in more details later in this article. In order to get a comprehensive understanding of the “arcball”, we will first illustrate the mathematical bases of using quaternion to describe rotations, and then move onto the mathematical foundation of the “arcball” algorithm, with the provision of pseudo code of it. At last, we try to apply this algorithm into research projects and provide of an analysis of the results obtained in our researches.

The distance of information transmission in fiber system can be affected by Line width Enhancement Factor. In this paper, the influence of chirp parameter in optical fiber communication system on fiber dispersion is analyzed as emphases. Taking Gaussian pulse as signal source, the impact of frequency chirp together with the Line width Enhancement Factor on the performance of optical fiber communication system is studied by solving nonlinear Schrodinger equation. Finally, it is concluded that the efficiency of transmission is improved dramatically by reducing the Line width of laser.

3-D rotation interaction is an indispensable function of 3-D imaging system of laser scanning, therefore it is also a hot topic of 3-D interaction research. The drag of mouse can be reflected by the on-screen movement of the cursor, when the dragged object is a 3-D object, the contradiction between it and the 2-D screen exposes. Aiming to resolve this problem, arc ball algorithm was used basing on quaternion. In this paper, the mathematical bases of using quaternion to describe rotations was illustrated firstly, secondly, the mathematical foundation of the arc ball algorithm was discussed, and then pseudo code of algorithm were provided. Lastly, this algorithm was applied into research projects and some research results were obtained.

Cavernous sinus hemangiomas (CaSHs) are rare vascular lesions in the cavernous sinus(CS). Gamma Knife radiosurgery (GKS) provides a treatment modality alternative to microsurgery. This study was conducted to describe a new classification of CaSHs based on their magnetic resonance (MR) imaging findings and determine the efficacy and safety of GKS in a large series of CaSH patients. From April 2007 to November 2012, 53 patients harboring CaSHs were treated using Leksell Gamma Knife model C (before April 2012) or Perfexion (from May 2012 ) at the Gamma Knife Center of Huashan Hospital. Of the 53 patients, 15 with definitive histopathologic diagnoses after surgery, 38 were diagnosed based on their MR imaging findings. There were 15 male and 38 female patients with a mean age of 52 (range, 25–76) years old. The characteristics of MR images of CaSHs were their extremely high homogeneous intensity on T2-weighted and FLAIR images: as bright as cerebrospinal fluid signal. According to the relationship between the carotid line and their location, CaSHs were classified into three types: the intrasellar, parasellar and mixed type. The mean volume of the tumors was 13.2 ± 8.2 cm3 (range, 1–41 cm3). A mean marginal dose of 13.3 Gy (range, 8–15 Gy) was directed to the 49 %–64 % isodose line (mean 53 %). Of the 53 tumors, 6 (11 %) were classified as intrasellar type. Eight (15 %) were parasellar type and the other 39 cases(74 %) mixed type. The mean radiological and clinical follow-up time of this study was 24 (range, 2–67 months) and 34 months (range, 2–73 months), respectively. The tumor control rate was 100 %. The mean tumor volume reduction was 79.5 % (range, 16.5 %–100 %) compared with the pre-GKS volume. Six months after GKS, MR imaging revealed an average of 60.2 % tumor volume reduction (range, 16.5 %–89.2 %). Twenty-nine cases (55 %) showed a >80 % tumor volume decrease. Neurologically, only two of these patients showed clinical deterioration, and 33 patients demonstrated an obvious improvement in ocular or endocrine disorders. At last follow-up, there were no more complications related to GKS, and none of the tumors progressed. Our study showed that GKS is a useful and safe therapeutic method for CaSHs as both a primary and adjuvant treatment. The new classification of CaSHs may help predict their clinical course during tumor development and treatment response after GKS. Further studies with long-term follow-up and larger numbers of cases are necessary to optimize the treatment conditions and verify the benefit of this treatment.

This study aimed to evaluate the effects of cantharidins, a traditional Chinese medicine, in chemotherapy for the treatment of hepatoma. From August 2011 to December 2012, 96 patients with hepatoma, who were eligible for transcatheter hepatic arterial chemoembolization and received cantharidins, were selected for comparison with the control group of 95 patients without cantharidins. The treatment effect, clinical symptoms and adverse effects were analyzed. The results of the study showed that the cantharidins group had a higher overall efficient rate than the control group (p < 0.001). The improvement rate of the Karnofsky score in the cantharidins group was significantly higher than that of the control group (p = 0.014). In the cantharidins group, there was a decrease in white blood cell (WBC) count and gastrointestinal response rates were lower than those of the control group (p < 0.05). Therefore, the traditional Chinese medicine cantharidins showed effects of easing the progress of liver cancer, relieving side effects of chemotherapy and improving the quality of life in the treatment of hepatoma.