Research Methods of Brain-computer Interface Technology

Brain computer interface(BCI) is an EEG based communication and control system between human and computer or other electric devices, which does not depend on the brain's normal output channels of peripheral nerves and muscles. It is a novel kind of human interface, may have applications in rehabilitation, control and other fields. The developming speed of brain computer research in recent years is high. Methods of how to use P300, SSVEP, ERS/ERD, SCP, spontaneous EEG and implanted electrode to realize BCI are introduced. Characteristic and limitation of different methods are discussed. Status, problems and application prospects of BCI technology are also included.     

THE LSP METHOD FOR INTERFACING AUTOCAD WITH HIGH-LEVEL LANGUAGE

On the basis of comparing with usual methods,a method for interfacing AUTOCAD with high-level language by LSP file is proposed in thispaper.It solves the problem that a large number of graphics are drawn continuallywhile DXF and SCR file are not in a condition to use.This method is simple andconvenient to make good use of AUTOCAD graphic functions.     

AC Impedance Study of the Interface between Cement Paste and Crushed Stone

The method of AC impedance spectroscopy has been applied to study the properties of interface between cement paste and crushed stone. The effect of interface between cement paste and crushed stone can be determined by comparison of three parameters in AC impedance spectroscopy.     

The Unified Representation of Interface Conditionsof Electromagnetic Quantities Using Exterior Differential Forms

A continuity condition of p-forms across a p-dimensional submanifold isderived.The,various interface conditions of electromagnetic quantities are obtained through theapplication of the continuity condition to Minkowski manifold of space-time.     

Application of Joint Element in the Stability Analysis of Rock Mass

According to the strongpoint and shortcoming of all kinds of plane joint elements and theirs applicable range, the basic theories of plane joint elements were introduced in brief. An example which utilized different plane joint elements to simulate the different sorts of discontinuity interface in rock mass was given, and the analysis result indicates that if only the constitutive model of a material is confirmed ,and some special element types are adopted,with the basic principle and approach of the finite element to simulate rock materials, a more satisfactory result can be obtained.     

Tree-crop interactions in maize-eucalypt woodlot systems in southern Rwanda

We studied the interaction between Eucalyptus saligna woodlots and maize crop in southern Rwanda. Three sites were selected and in each, a eucalypt woodlot with mature trees and a suitable adjoining crop field of 12.75 m × 30 m was selected. This was split into two plots of 6 m × 12 m and further subdivided into nine sub-plots running parallel to the tree-crop interface. Maize was grown in both 6 m × 12 m plots and one of these received fertiliser. Soil moisture, nutrients and solar radiation were significantly reduced near the woodlots, diminishing grain yield by 80% in the 10.5 m crop-field strip next to the woodlot. This reduction however affects only 10.5% of the maize crop field, leaving 89.5% unaffected. Spreading the loss to a hectare crop field, leads to an actual yield loss of 0.21 t ha⁻¹, equivalent to 8.4%. Expressing yield loss in tree-crop systems usually presented as a percentage of yield recorded near the trees to that obtained in open areas may be misleading. Actual yields should be reported with corresponding crop field areas affected. Variation in grain yield coincided with those for soil moisture, soil N and K; all increasing from the woodlot-maize interface up to 10.5 m and remaining similar to the values in open areas thereafter. Solar radiation continued to increase with distance up to 18 m from the woodlot-maize interface. Harvest index in unfertilised maize exceeded that in the fertilised treatment reflecting the crop’s strategy to allocate resources to grain production under unfavourable conditions. Fertilisation increased maize yield from 1.3–2.6 t ha⁻¹ but the trend in the woodlot effects on maize remained unaltered.     

固体火箭发动机粘接界面湿热老化实验

对固体火箭发动机粘接界面试验件进行了不同湿热条件下的加速老化试验,并测量了不同老化时间粘接界面的扯离强度,描述了湿热老化试验和性能测试中的试验现象,结合复合材料微粘接结构吸湿规律对试验现象和撤离强度随老化时间变化曲线进行了分析。研究结果表明:衬层-推进剂粘接界面是固体火箭发动机粘接结构中最薄弱环节,应予以重点考虑;湿热老化促进了环境水分从衬层–推进剂界面向推进剂内部的扩散和渗透,致使弱边界层向推进剂内部扩展,导致了衬层-推进剂界面粘接强度的降低。试验件平均扯离强度随老化时间呈下降趋势,中间有一个强度趋于稳定的平台期。      

Target-based Security Management Architecture Applied to Management Information System

In order to implement the security management of management information system (MIS), a target-based security management architecture is proposed. For MIS users, the user interface (UI) is the only way to interact with the MIS system, so all the objects (targets) which need to be managed on UI is registered first, thus for every target the state such as enabled, not enabled, visible, not visible, readonly etc., is assigned. For some users, a set of targets with some state is assigned so that the management granularity in MIS can reach any degree. This approach provides a very flexible way to the security management in MIS.     

IMPROVING ULTRA-HIGH MOLECULAR WEIGHT POLYETHYENE(UHMW-PE)FIBRE SURFACE ADHESION BY PLASMA TREATMENT

It's very difficult to study high-strenth compositesbecause of the poor adhesion of polyethylene fibres caused by its specialstructural qualities.This paper reports a study of changing the surfacequalities of ultra high molecular weight polyethyene(UHMW-PE)fibres of different draw ratios by plasma and acid treatment.It alsodevotes to the experiments of measuring the fibre resin adhesion bythe pull out technigue,and studies the mechanism of the interface failureby SEM.The experimental results show that there's a significant impr-ovement in the adhesion between the UHMW-PE fibres and the resinafter the plasma treatment and it can be four times stronger,dependingupon the draw ratios of fibres and plasma parameters,The interfacefailure in the pull-out test involved developes along the fibre-resininterface within the fibre,and the skin of the fibre is peeled off.Theadhesion can be improved by combining the plasma etching technique andother methods of treating the surface of UHMW-PE fibre.     

COMPUTER RESIMULATES ON THE FCC:BCC PARTIALLY COHERENT INTERFACE

The structure of FCC: BCC boundary, which is expected to be partially coherent and to be defined by Nishiyama-Wasserman orientation relationship,is resimulated by computer. The results show that the misfit dislocation is not the necessary structural element on the partially coherent FCC:BCC boundary,and introducing the structural ledges in two directions brings about an increase in the interfacial coherency and a decrease in the interfacial energy. A structural model of FCC:BCC partially coherent interface is made,which replenishes with and amends the R-A model.     

A METHOD FOR THE ORIENTATION OF CHINESE CHARACTERS IN THE INTERFACE PROGRAMMING OF AUTO CAD DXF DOCUMENT

The orientation of Chinese characters is very importantin the interface programming design of Auto CAD DXF documents.Beca-use some parameters are automatically computed by the Auto CADsystem,it is very difficult for Chinese characters to be oriented in DXFinterface programmings.This paper reports the calculating method of ori-ented parameters and the orientation method of Chinese characters in theinterface programming of DXF documents,and gives a general Fortran 77subroutine for the orientation of Chinese characters.The method solves thedifficulty of the orientation of Chinese characters in the interface program-mings of DXF documents,and makes it convenient for various CAD pic-tures to be oriented in Chinese Characters.     

Study and Design on S5933 Special Chip Data Acquisition System Based on PCI Bus

The paper explains the data transfer mechanism based on the PASS-THRU channel of S5933, and gives a method to develop data acquisition system based on PCI bus, the problem of designing the PCI interface controller is avoided, saving time and cost of development production. The use of CPLD makes the stucture of the system more integrated. The 32-bit data acquisition system,the speed of data transmission is faster,the CPU resource and PCI bus resource are spared.     

Layered E-R Model Based Input Technology

The traditional E-R's model can abstract the real world strongly, but the relationship among entities in E-R's model is very mixed and disorderly .In order to improve the productivity of the module of data input,the layered E-R model based input technology is presented. The logic model( relational model) produced by the traditional E-R model is layered by primary keys. According to the layered model ,the input interface is produced .First the input interface of 1th-tier entity is produced .By using the input interface of 1th-tier entity ,the input interface of 2rd-tier entity is produced ,until the input interface of the last tier is produced.     

The Ledge Structural Models of FCC:BCC Partially Coherent Interface

The structure of FCC: BCC partially coherent interface is simulated by computer. The results show that the interface structure is varied with the orientation relationships. The structural models of varied orientations are made, which are defined by the lattice parameter ratio afcc/abcc= 1. 26 and ranged from K-S to N-W orientation relationship. The amount of deviation of the apparent habit plane from atomic habit plane {111}fcc is a function of orientation,and ranges from ca. 12 degrees to ca. 30 degrees. Computer simulations also found that the misfit dislocations could not be certain to exiet on the FCC:CC partially coherent interface.     

春季生物膜对营养盐在水-沉积物界面扩散的影响

为了明确春季大沽河河口潮滩养殖功能的退化是否由食物（底栖藻类）匮乏所致,2009年5月在大沽河河口潮滩采集柱状沉积物样,利用氯化汞抑制沉积物表层生物膜的活性,研究生物膜对营养盐在水-沉积物界面迁移扩散的影响程度。结果表明,沉积物既可以是水体中营养盐的“源”也可以是其“汇”;在河道的近海侧,沉积物表面的生物膜会促进磷酸盐自沉积物向水体扩散;在其余区域,沉积物表面的生物膜会抑制营养盐自沉积物向水体扩散;在该河口潮滩,沉积物表层的生物膜均会抑制营养盐自沉积物向水体扩散。研究表明,春季大沽河河口潮滩贝类底播养殖功能的退化,并非食物短缺所致。     

Status Quo of WearComp-based Output Interface

It emphasizes human-centered and robot collaborating with human when robot is employed in dynamic, unstructured environments or those tasks which can not be fulfilled without human. To achieve constancy interaction, WearComp-based interface devices should be adopted. This paper analyzes and compares the status quo of multiple output modalities, interfaces and devices including display, sound, vibration, tactile and force, and sums up the character and limitation of multiple WearComp-based output technologies and devices and the methods to avoid it. To prevent VR from shielding local environment and monopolizing the bandwidth of transmission and the resources of WearComp-based output devices, AR should be introduced to enhance human awareness of local environment with filtrated information of tele-environmental and tele-robot.     

Effect of surface defects on anodic oxidation coating of7075 aluminum alloy

The interface interaction between geogrid and soil is one of the key issues on geosynthetic reinforced soil structures. Comparative analysis of properties of geogrid clay interface under the different normal stresses and water contents of clay were conducted by medium sized pullout tests. The results show that ultimate pullout force of geogrid, interfacial cohesion and frictional coefficient are significantly affected by water content of clay. Ultimate pullout force of geogrid tends to be remarkably different when subjecting to different normal stresses at a lower water content. And frictional coefficient of interface decreases with the increase of water content, and interfacial cohesion has a tendency to increase followed by decrease with the increase of water content. Moreover, aforementioned three parameters can keep constant when water content is close to value at plasticity limit. The curves of load and displacement possess three stages: linear increase, non linear increase and ultimate pullout. As water content increases, the interval nonlinear changing stage is not conspicuous. Furthermore, it is found that geogrid strains in transversal ribs tend to increase but to reduce in longitudinal ribs when last level load is kept for given hours and then followed by unloading pullout force.     

NEW PROGRESS OF IN SITU X-RAY DIFFRACTION ELECTROCHEMICAL STUDIES

This paper reviews the progress of in situ X-ray diffraction electrochemical study for the formation and transformation of electrode surface film;and the dynamic structure of electrode/solution interface at Chongqing University.