Showing papers in "Journal of Shenyang Architectural and Civil Engineering Institute in 2005"

Study on Smart Home Network Technology Based on Wireless Sensor Network

Abstract: The research of smart home based on the wireless sensor network is done in view of the speciality of intelligent home and the actuality of intelligent home network.Making use of the speciality and technology of wireless sensor network,the model of smart home based on wireless sensor network is made.The wireless chips based on the technology of IEEE802.15.4 are used to reduce the power-cost in wireless sensor node.The smart home network based on wireless sensor network can control our home timely and availability,which makes our life convenient,comfortable and highly efficient.

Green Space Accessibility Research Based on GIS:Taking Shenyang as an Example

Abstract: Urban population increases quickly along with the fast development of urbanization,and the environment improvement becomes one of the key factors for urban sustainable development.Green space can improve the urban environment and urban population's life quality.A method,assessment in Green space landscape accessibility,is proposed in this study based on potential energy model,taking population density,road distribution,land use and green space spatial patterns as parameters.The method emphasizes the spatial distribution pattern of green space and the valid service for urban people of green space.The green space of Shenyang city area was studied as a case.The result indicated that:①68.08% green space in the study area is in 1st level of the accessibility class,and 2nd,3rd,4th,5th levels of area are 21.64%,7.89%,2.00%,0.33% respectively.The spatial distribution pattern of green space is basically reasonable,and the green space may provide a good service for the people in the city.②The result also points out the construction and the direction of the green space in study area in future.③Green space landscape accessibility provides a useful index in the assessment of current situation and in city green space planning.

Research on the reform of college English teaching

Abstract: Abstrcat After analyzing the present English teaching in universities, there are a great number of teaching problems to be solved promptly, such as teaching guidelines, building of teachers' group, mode, management system and ways of test,etc. Teaching Requirements of English Course in Universities, issued at the beginning of 2004, make the present goal of English course teaching in universities--to meet the desirability of the social development, to meet the subjective demands of both sides of learning and teaching, to equip with technical support whose core is computer network, to possess the essential outside language terms of English study and to make a reservation accurately. In view of this, the English teaching in universities should be researched and practiced firmly on the reform of traditional teaching mode, completion of teaching management system, perfection of teaching evaluation system, optimization of English course system and teacher management and training system.

Wind Load Simulation by Superposition of Harmonic

Abstract: Wind load simulation and the wind vibration responses of a structure by computer numerical simulation are put forward in the paper.The time history of pulse wind velocity and wind pressure on the structure has been simulation based on Davenport wind speed power spectrum and Shinozuka theory.Its power spectrum and the correlation function are calculated out.The wind vibration responses of a 12-story structure are calculated from this method. Comparing its power spectrum and the correlation function with the measurements in the practical test validates the efficiency of the simulation.The example of 12-story structure shows the value for the engineering.

Equivalent Moduli Method in the Finite Element Analysis of Reinforced Concrete Structures

Abstract: When the performance of mega structure is studied,computational efficiency and accuracy are always not compatible.It is usually necessary to simplify the finite element model.Based on the theory of equivalent moduli for fiber reinforced composites proposed by Y.H.Zhao and G.H.Weng,two sets of equations of revised equivalent moduli for reinforced concretes with the rebar orientated in unidirection and in three perpendicular directions are derived in this article. The experimental study was developed to prove the correction of these moduli. In the application of this method RC could be treated as homogenous materials,so the analysis process becomes much easier,especially suitable for the simulating of those huge volume and complicated structures.

The Model of the Cementing Matrix Powder Group Fractal Geometry Denseness Effect

Abstract: This paper uses the fractal theory to analyze the fractal characteristic of cement and superfine powdery mineral grain group.It compares the highest density perfect distribution curves of the conventional powder tightest accumulation classical theory based on the fractal geometry denseness effect model of the cement multiplex material's powder group.The study shows that the fractal models accord with the conventional Andreasen equation U(D_p)=100(D_P/D_(pL))~(1/2)when the fractal dimension is 2.515 and they accord with the conventional Andreasen equation U(D_p)=100(D_p/D_(pL))~(1/3)when the fractal dimension is 2.697.The conventional model is just a special example of the fractal models.Fractal models provide an important theoretic gist for the further exploration of the internal disciplinarian in which the superfine powdery material influences HPC closeness.

Effects of Admixtures and SRA on Early Age Shrinkage of Concrete

Abstract: Effects and mechanics of superplasticizer,pulverized fly-ash and blast furnace slag on the early age shrinkage of concrete were studied to reduce the early age shrinkage and control the early age shrinkage crack.The early age shrinkage of 12 different part mixture of concrete was measured by means of self-designed and manufactured early self-shrinkage testing plant.Testing results indicated that the early age shrinkage of concrete with superplasticizer was about 4 times more than that without superplasticizer.It reduce by 5%～15% and 8%～20% for fly-ash and slag respectively.And the shrinkage reducer agent could reduced the early age shrinkage of concrete by more than 45%.The early age shrinkage of concrete increased greatly with superplasticizer and reduced when fly-ash or blast furnace slag were added as the replacement of cement.The compatibility of shrinkage reducer agent with superplasticizer and slag powder and fly-ash was preferable.The shrinkage reducer agent could reduce the early age shrinkage,so it was one of the effective methods to control the early age shrinkage crack of concrete.

Failure Mode Analysis for RC Slab under Explosive Loads

Abstract: Explosion is a kind of load acted on the buildings with powerful energy and short duration compared with normal loads.RC slabs are the very common members for buildings and they will have different failure modes,which usually include flexural and direct shear ones,with the changes of peak pressure and duration time of explosive load.At first the explosive load on buildings can be simplified into triangle impulse pressure in order to make the simulation easier and then a one-way RC slab under the explosive load can be used as an example to be analyzed by the powerful FEM software-ABAQUS to simulate numerically the behaviors of the slab.The dynamic increasing factor (DIF) and strain rate effect on concrete and reinforcement materials are used.Flexural and shear failure modes as well as strength rules are also applied in the paper.At last the failure modes for the RC slab under the different loads are given by the comparison of analysis results for the same impulsive but different peak pressures and duration time of explosive loading.

College English teaching reform based on college English Curriculum Requirements

Abstract: Based on the newly-issued College English Curriculum Requirements, this article mainly discusses the college English course reform in Shenyang Jianzhu University from such aspects as teaching conception, teaching methods, teaching techniques, and teaching evaluation. It aims to, through analysis and summarization, discover an optimized path of college English course reform to suit the case of universities alike and cater the needs of social demands.

Analysis of the Thermal Characteristic of PCM Wallboard Including Fatty Acid

Abstract: The study is to carry out an analysis of the thermal performance of phase change wallboard including fatty acid PCM,and probe into the possibility of using its thermal performance to reduce building energy consumption as well as the load of the air conditioner.Considering climatic conditions,and day and night length in the Northern summer and differential prices of electricity at the peak-valley,DSC is utilized to test and analyze the material function of phase change energy storage,select two kinds of fatty acid as phase change material,make phase change wallboard,and carry out a thermal functional analysis of performance of the wallboard.Through the analysis of DSC,two suitable fatty acid kinds of PCM mixture are selected for areas with cold winter and hot summer.Their phase change temperatures are in the range of real indoor air design temperature,at the same time they have high latent thermal capabilitu.The mixed PCM into gypsum board can have latent and relatively high heat after dissolution of PCM.Its suitable phase changes temperature range and peak function as a prerequisite for utilizing natural cold wind at the electricity peak and valley.Phase change wallboards not only remove the peak and fill out the valley,reduce building energy consumption,reduce air conditioning load,but also increase economic efficiency and meanwhile improve comfort of indoor room,and explore a new space for air conditioner in Northern China.

Experimental study on concentrically compressed stub columns reinforced by concrete filled CFRP-steel tube

Abstract: The process of making stub columns reinforced by concrete filled circular CFRP-steel tube was introduced.The characteristics of stub columns reinforced by concrete filled circular CFRP-steel tube was disdcussed based on the strength tests of 8 concentrically compressed stub columns reinforced by concrete filled circular CFRP-steel tube and 4 concentrically compressed stub columns reinforced by concrete filled circular steel tube.The load-strain curves of the two columns when compressed concentrically were compared.The enhancement curves of the outer concreter to ward the ultimate strength of concrete filled circular CFRP-steel tubular stub columns as well as the load-strain curves of CFRP and steel tube were demonstrated.It was found that steel tube and CFRP could work well together.

Tactics of sustainable development of little-size town based on the conceptual frame of PSR

Abstract: Based on the preliminary discussion of connotation of sustainable development of little-size town, we use the conceptual frame of Pressure-State-Response to put forward an index system of sustainable development of little-size town. Through analyzing various indexes, we advance some tactics which promote the development of little-size town: establish conception of scientific and developmental; make the way of scientific economic development, change from straightforward to intensivism. Assort population, environment, ecosystem with the development of economical; try for overall improvement of society.

The Research about Affecting Factors of Resistant Freezing Critical Strength of Low-temperature Concrete

Abstract: This paper explores the effects of different curings W/C and ages on the infant strength and the infant resistant freezing critical strength of concrete 30 and attains the infant strengths under different temperature curings and the resistant freezing critical strengths of the different kinds of W/C concrete with the dry and wet face state by use of the once artificial freezing method according to the standard-95% of strength cured under standard condition.In conclusion,the time to attain the resistant freezing critical strength of concrete with dry face and wet face increases from 12h to 26h and from 36h to 70h with the increase of W/C from 0.4 to 0.6.The resistant freezing critical strength of wet face concrete is 8.5～9MPa and the resistant freezing critical strength of concrete with dry face is 2.5～3MPa.

Influence of Crystal Stabilization on the Strength of high B-lite Sulphate-aluminate Cement

Abstract: In order to create high B-lite sulphate-aluminate cement and make use of industry hyproduct and the influence of some crystal stabilization on the strength of high B-lite sulphate-aluminate cement usder different temperature system,by mixing crystal stabilization into cement by means of single or compound mode and burning,grinding,determinate W/C,moulding and measure strength,the authors carried out experiments which proved that mixed cement by means of single or compound mode has different degree development,in addition in the influence of temperature system on strength of the cement is marked,and therefore drew the conclusion that the influence degree of single mode to the cement from big the smal one by one in order is B_2O_3,SO_3,TiO_2The effect of compound mode is obviously good to single modeThe late strentth develops fast in (1250℃) and the early strength goes up in (1300℃),because β-C_2S is easy to form in (1250℃) and anhydrate sulphur aluminum calcium in (1300℃)

Application of the DEM on the Nonlinear Analysis of Reinforced Concrete Members

Abstract: In this paper,the distinct element method (DEM) is applied to analyze the nonlinear static analysis of RC members,and the distinct element model for reinforced concrete members is developed,which is named as segment-multi-spring model (SMSM).A program is also developed in this paper for the nonlinear static analysis of RC columns on the basis of SMSM,to analyse the response of reinforced concrete columns under monotonic and cyclic horizontal loads.The numerical results prove that the SMSM is reliable,and the application of the DEM on RC structures is practicable.The application range of DEM is greatly enlarged in this paper.

Performance Analysis and Evaluation of CAN and Ethernet

Abstract: CAN and Ethernet,based on event-triggered,are the two of typical networks that are applied in industrial computer-controlled systems widely.The analysis of their network performance is studied in this paper,which will set up a good basis for further improvement and realization of control network.Firstly,a discussion about the features of the CSMA/CA based CAN and the CSMA/CD based Ethernet is presented in this paper.Secondly,the quantitative and the qualitative analyses of CAN and Ethernet are conducted and compared in the following performance aspects: the message frame format,data coding efficient,deterministic and bounded characteristic of messages,and the relation of throughout,average message delay,collision probability,network utilization,network efficiency and message finish rate with arriving interval of messages.Finally,the analysis results indicate that CAN is superior to Ethernet in application in which message traffic has stringent time constraints and the direct transmission distance between two nodes is short.

Design Approach of Stiffeners in Extended End Plate Connections and Finite Element Analysis

Abstract: End plate stiffener failures occur in a number of tests in recent years,which shows an inadequacy of the knowledge about the role of stiffeners in this type of connectionsNo relevant rule is given in design codes for steel structuresA strength requirement for the stiffeners from two aspects is proposed to avoid the abrupt stress transmission from the beam flanges to stiffeners and from the stiffeners to the end plate and to assure uniformity of forces in bolts inside and outside of the flangesThe effectiveness of a triangular stiffener relative to a long rectangular plate in transmitting stresses is taken into accountA balance between the force transmitted by the stiffener and that by the beam flange is consideredFE analysis using contact element in ANSYS is carried out to compare the behavior of connections without stiffeners and those with stiffeners of different configurations and thicknessesIt is found that:(1)the common stiffeners often yield or/and buckle prematurely;(2)stiffeners designed in this study can reduce the end plate deformation,increase arm length of the connection against the bending moment,assure uniformity in bolt forces,and postpone the buckling of the compressed flange efficiently

Finite Element Analysis of Castellated Beam Maximum Moment Capacity

Abstract: In order to further get to know maximum moment capacity of castellated beams,this paper will use finite element analysis program-ANSY here to analyze the circular and polygon holes' castellated beams with the same span and the same number of openings,and then to obtain different opening section and different ratio's influence on the castellated steel beam's moment capacity.As to the two different kinds of sections,the strength of circular castellated beams will be huger than that of polygon castellated beams with the same condition.The result shows that the influence of the opening ratio's and section on the castellated beams can be simulated by use of the finite element analysis program.At the same opening ratio's,beams will reach the elastic phase ,then the elastic-plastic at the last phase of plasticity.At the same time,plasticity will develop the opening section and circumference.The web shows the bulking phenomenon.It expresses that the beam reaches the ultimate failure,and then causes the lateral tort at the middle of beam and loses the overall stability.There are stress concentrations on the corner of the opening.The finite element maximum moment capacity of circular castellated beams are higher than that of the polygon castellated beams with the increasing of opening ratio.

The Vibration-proof Research under the Wind Load of Random in the High-rise Structure in Tower

Abstract: This essay brings out a new type of damper——gyroscope vibration-proof damper in order to restrain vibration in high-rise structures in tower under the wind load of random.Based on the theorem of gyroscope dynamics and random vibration,mechanism of damper that restrains vibration is studied and the model test of this kind of damper is carried out.The result shows that it can effectively prevent the vibration in both the theorem and the model test.The higher strength of the wind load,the more obvious the efficiency.This damper can also prevent the development of galloping in high-rise structure in tower.

Mechanical Property Analysis about the Concentrically Compressed Concrete Filled Circular CFRP-Steel Tubular Stub Columns

Abstract: Based on the experimental study,mechanical property of the concentrically compressed concrete filled circular CFRP-steel tubular stub columns is analysed. First,mechanization of this kind of structures was analysed according to different stages,and then,stress developments of concrete,steel tube and CFRP tube are given. Second,the stress-strain curve of this kind of structures is determined based on the above-mentioned,and several stages are defined: elastic stage,elastic-plastic stage,strengthening stage and descending stage. The most important distinctive feature of the stress-strain curve,compared with that of the concentrically compressed concrete filled circular steel tubular stub columns,is that there must exist a descending stage after the ultimate load bearing capacity was reached. Third,the simple calculation method of load bearing capacity is studied and the ultimate equilibrium method is recommended.

On-Line Signature Handwritten Verification Algorithm Based on Stroke Matching

Abstract: On-line signature handwritten verification is a topic in the field of biometric authentication nowBy comparing the picture,stroke,speed and pressure of input signaturs with genuine signatures in database,the computer can distinguish the true or false of a handwritten signature real-timelyStroke-matching and result judgment are the keys to this problemThis paper presents a stroke-matching algorithm of handwritten signature verificationThe algorithm is effectual to be examined by signature data from SVC 2004(First International Signature Verification Competition)The FRR(False Reject Ratio) is 20% and all forgeries are rejectedThe paper also introduces distance calculation formula based on weighting H′ module to calculate the difference between input signatures and true signaturesOn-line signature handwritten verification is very convenient,quick-made,suitable to verification and its effectiveness has been illustrated by practical examples

Theoretical Analysis of Curved Beam with Fixed Simple Ends

Abstract: This paper is to offer a kind of convenient and effective method to the unmentioned transverse displacement problem of the simple fixed ends,at the same time,offer new theoretical basis for the curved beam design.The paper applies the theory of structural mechanics to resolving the supportive forces of the hyperstatic structure,after then,to resolving the internal forces and the displacement according to the static structure.Ultimately,the analytical expressions for internal forces at an arbitrary position and displacement in loading direction are derived for a transverse point load acting at an arbitrary position,and the expressions are simplified ulterior for the convenience of the engineering application.The correctness of the results is validated by the corresponding straight beam.In addition,the results of present theory are compared with the finite element method data for further illustrating its correctness.The theoretical application testifies that the results accord with the fact,so they may be used in the design and the analysis of the curved beam.The theory supplies a new attempt to the analysis of the structure.It has the theoretical and applicable significance of actual engineering.

The Improvement of Laplace Operator in Image Edgedetection

Abstract: This paper is done in order to improve the precision and clarity of old Laplace operaror in edge detection so that the basic characteristics of image can be studied more precisely.The effect of edge detection can be greatly improved by means of extending the old Laplace operator from the 3×3 matrix to 7×7 matrix,adding some non-special detection direction to some special detection and setting the different coefficient according to the distance of each point from the center point.The experimental comparison of the old Laplace operator with the improved operator has shown that the edge becomes much more continuous,more accurate and clearer,and the fake edge can be avoided effectively when the new Laplace operator is used in edge detection.At the same time,it can detect the edge that the old operator cannot detect and remedy the limitation of the old operator and the result is very good. So it can be concluded that by means of improving the Laplace operator,the effect of edge detection can be boosted,the continuity of edge can be well maintained and the edge can be detected precisely.

Data Fusion Technique in Structural Health Monitoring

Abstract: In order to make full use of different time-space multi-sensors information resources and to obtain the coincidence decision-making and assessment task of the objective from large-type structural health monitoring system,this paper,firstly,introduced the basic concepts and principals of multi-sensors data fusion.Secondly,the feasibility of the multi-sensors data fusion technique applied to the structural health monitoring was discussed.Thirdly,the method of data fusion-based structural health monitoring and diagnosis was emphasized and,the wavelet probabilistic neural network data fusion damage detection technique was proposed.Finally,it was investigated and discussed for data fusion technique to be applied in structural damage detection.The result showed that the method of data fusion-based structural health monitoring is feasible and effective.

Online Measurement of Roundness Errors of Parts Based on PMAC

Abstract: In order to pursue the perfect combination of precision,cost and efficiency,the study on the corresponding test equipment is necessaryWe designed and integrated an online measurement and machining system for cylindrical surface grinding of parts,whose central parts are IPC and PMAC-PC which together constitute the main computer and the follow computerBy use of PMAC,the dynamic link library of Pcomm32 is provided for users to complete the link of the main computer with the follow computerMultimedia timer technique adopted to real-timely gather data and double buffer memory technique works out real-time gatheringdata in great memory and display,and so onSoftware and hardware of the main computer MACSYM are finished based on the above techniquesThat provides the foundation for the application of open CNC in the precise processing as well as the integration of processing and measurement

The Quantitative Analysis of Microstructure Parameter of Soft Soil

Abstract: In order to analyze the consolidation creep law of soft soil,the Scanning Electronic Micro-scope(SEM) and Video-lab Image Processing System were employed to observe the changing conditions of microstructure of soft soils distributed in Yingkou area,Liaoning Province of China.The microstructure parameters which can be used to explain the law of creep deformation are determined,and the results show that there are numerous micro-structure parameters which will alter with change of the creep stress.Among them the parameters which show the ordering extent of microstructure units have close relation with the development of compressive creep,such as the probability entropy(H_m)and fractal dimension value(D_d).So both probability entropy and fractal dimension value can be used to study the problems of creep of soft soils.

Influence of Stiffness of Glass Panels and Joint Constraints on Dynamic Properties of Monolayer Cable Net for Point-supported Facade

Abstract: Monolayer cable net system for point-supported glass facade has become more and more popular in recent yearsThe characteristics of dynamic property analysis on pretressed structures are presented in this paper,and finite element program is developed to obtain the frequencies of self-vibration of cable netsThe contributions of mass and stiffness of glass panels to dynamic performance are analyzed by comparison of variations of frequencies of self-vibration before and after the installation of glass panelsMeanwhile,four types of joint connection between cable and glass are introduced to simulate the realistic connections,and their influences on the frequencies of vibration are comparedExperimental study on the dynamic characteristics of a one-tenth scale model of monolayer cable net for glazing in New Poly Plaza of Beijing has also been carried out in this studyThe frequencies of cable nets decrease owing to the inclusion of the mass of glass panels,which is in contrast with the effect of the stiffnessGenerally,the influence of mass on the frequency of structure is greater than that of the stiffnessThe fluctuating amplitude of frequencies due to the influence of mass and stiffness of glass panel is larger for thicker glass panel than for thinner oneTranslational constraints between nodes of cable and glass have few effects on dynamic characteristics of planar cable nets,contrary to rotational constraints that are devised to simulate the silicon joint by rotational springResults of the constraining connection mode by using translational spring agree with those obtained from the experiment

The Comprehensive Evaluation of HVAC Facility Management Based on AHP

Abstract: This paper starts from the development of facility management of HVAC system,combined with the development status quo home and abroad to set up the comprehensive assessment index system of HVAC facility management.The purpose is to find an impersonal and logical comprehensive assessment index system of HVAC facility management by means of a questionnaire.It deals with the collected data by use of Analytic Hierarchy Process in order to set up a comprehensive assessment model of HVAC facility management,find the authority of every index in the assessment system and check up the coincidence indicator.As a result,the AHP is applicable to the comprehensive evaluation of HVAC facility management.It also needs to make the comprehensive assessment index system of HVAC facility management as perfect as possible.It is certain to make sense of interrelated codes of HVAC facility management through the investigation of the system.

A Method of Lateral Earth Pressure Calculation Consequent upon Displacement for Excavation

Abstract: For calculation of earth pressure on condition that retaining structure,lateral displacement is within limiting values,and a formula for earth pressure consequent upon displacement of retaining structure is to be built.According to general characteristics of earth pressure variation,the relationship between the pressure and lateral displacement of support structure is expressed by a hyperbola,and the soil on both sides of retaining structure is simulated by nonlinear spring partly in imitation of Winkler Foundation model.The result shows that the formula for earth pressure according to lateral is placement is developed,and therefore we draw the conclusion that it is proved by the sample that the calculation results of presented formula well tally with field dates,and the formula is plain and practical.

Optimum Installation of the MR Dampers for the High-rise Structures by Genetic Algorithm

Abstract: An optimal installation method of MR dampers using genetic algorithm(GA)is put forward in order to reduce the vibration responses of high-rise building under wind loadThe dynamic model and equation of motion of the structural system are firstly set up and some parameters are determinedMoreover,an optimal installation model based on genetic algorithm is set up and some weight coefficients for safety and economy are inducedSo variety of installation plans are derived numerically from different standard levelsIn order to illustrate the simulating procedures,a 12-story reinforced concrete frame structure is used numerically as an example to show the optimal steps and main ideas and the optimal placement schemes are suggested at the endThe results of the simulation show that GA can be used effectively and economically in the optimal installation design of MR dampers in high-rise buildings to decrease the structural vibration responses