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As a new generation of photovoltaic devices, organic polymer solar cell (Organic Solar Cell, OSC) have attracted wide attention of researchers in recent years because of their unique advantages such as simple process, low energy consumption, low cost and large area preparation. However, the development of OSC has encountered bottlenecks: the low carrier mobility of photovoltaic materials forces the thickness of the active layer of OSC to be reduced as much as possible to meet the requirements of effective collection of photogenerated carriers, while the thinner absorption layer will lead to serious optical absorption loss and device performance degradation. Therefore, how to enhance the optical absorptivity of OSC on the premise of effective carrier collection has become a research hot-spot. Based on this characteristic, with the help of finite element method, the structure model of OSC with multi-tip metal nanoparticles is established, and the effects of metal nanospheres and star particles on OSC light absorption factors are studied systematically. Firstly, the effects of introducing metal nanoparticles into different functional layers of OSC (active layer and buffer layer) are compared and analyzed to determine the introduction location of metal nanoparticles in OSC. Secondly, the localized resonance enhancement rules of spherical and cubic metal nanoparticles in the functional layer are discussed. Combined with the theoretical model, the optimal design method of metal nanoparticles structure parameters (size and period) is established. The results show that the absorption enhancement of metal nanoparticles in the active layer of OSC is higher than that in the buffer layer. On the one hand, it can stimulate more electron hole pair separation, improve the separation rate of electron hole pair, on the other hand, it can also make the separated electron hole to obtain more energy, recombination becomes relatively difficult, and the arrival rate of the battery electrode is improved.

The AlCrFeNi high entropy coating was successfully prepared by mechanical alloying and vacuum hot pressing sintering technique on Q235 steel substrate, and the microstructures and microhardness, wear resistance and corrosion resistance were characterized in detail. Results showed that single body-centered cubic solid solution phase appears when the blended powder is ball milled for 30 h. The vacuum hot pressing sintered AlCrFeNi high entropy coating with single BCC solid solution is about 500 μm in thickness, which metallurgically bonded to substrate. The microhardness of the AlCrFeNi high entropy coating is about 520 HV, more than three times larger than that of the substrate. The wear resistance and corrosion resistance of the coating in 3.5% NaCl solution are greatly improved compared with the substrate, showing a dramatic reduction in average corrosion rate and wider passive range.

High alumina foam ceramics products with low density, high specific surface area, low thermal conductivity, corrosion resistance and other excellent physical and chemical properties are suitable for chemical, metallurgy and other related fields [1-4]. Alumina foam ceramics that compression strength increased by 200%, was prepared by Rizwan Ahmad through impregnation process using foamed rubber [5]. However foamed rubber was expensive and could be decomposed creating poisonous gases at high temperature. Zhou l z [6] prepared mullite porous ceramics with high strength by gel-casting method. Gel-casting is an effective method for preparation of ceramics products with large size and complicated shape. Fiber reinforced dense ceramics composite materials with excellent performance have been studied widely [7-10], it is also an important issue to adequately investigate the reinforcement of porous ceramics with fiber.

The sliding mode control approach based on double power exponential reaching law is proposed for the hydraulic servo system. With the example of the hydraulic servo system in the lab, the mathematic model is established and the new controller is presented and simulated. Simulation results show that: the proposed approach has high track precision, fast response, small chattering and ensures dynamic quality of the system.

In recent years, with the development of modern technologies and safety science, catastrophic accidents tend to be avoided successfully. However, general accidents which cause minor loss or casualties still occur occasionally and hence become main part of all accidents. Therefore, to make effective control of general accidents, fault trees are established based on the analysis of historical general accidents. The influencing factors are roughly divided into human factors and equipment system factors. This paper focuses on human factors and the relationships between the factors and general accidents are analyzed using the improved analytic hierarchy process (AHP) and methods of risk identification. The importance of the factors is thus evaluated. Results of the evaluation are helpful to management.

Engine intake system is one of the important parts of the engine which affects the engine’s volume efficiency and the uniformity of air entering to each cylinder directly Wherein the intake manifold with variable length is the important part of the intake system , has great significance value to research. Due to the structure of the manifold is complex, considering the manifold structure which affects the simulation accuracy, the principle of reverse engineering was used in this paper. Firstly, the laser scanning technology was used to obtain the point cloud data of the intake manifold.And then the cloud data was dealed by software Geomagic Studio12、NX Imageware13.The software UG8.0 was used to reconstructure the 3d intake manifold with variable length model.

The performance of the engine air intake system directly affect the working performance and fuel consumption, where the intake manifold design is the key.In this paper aimed at L91 Engine intake manifold ,firstly theRE(Reverse Engineering)technology was usedto rebuild the3d model of intake manifold.And then the internal flow zoneof the intake manifoldwas meshedin the pre-processing software ICEMand the internal flow fieldwas analyzedin the softwareof Fluent.The numerical model was verified by comparing the simulated and measured results. And then based on the numerical analysis of the internal flow characteristics of the intake manifold, the structure of variable-length intake manifold was come up with and finally was numerically proved to be better than the normal one.

The purpose of this study was to analyze the existing problems and put forward the corresponding settlement measures with the basic data of road transport facilities, water supply and drainage facilities, energy and power facilities, environmental facilities and communications facilities of 31 provincial capital cities and municipalities directly under the central government of China. AHP was used to get the comprehensive value and orders of overall level of infrastructures’ safety in major big cities. Results of the 31 city infrastructure overall safety level of sorting were summarized, and the existing problems and the reasons were got. Conclusion was drawn that the overall safety level of infrastructure in China needed to be improved and the infrastructure security level of east central area was higher than the western region with a poor gap. The economic development level, the degree of government’s attention, population density together with natural conditions were all important factors which influence the urban infrastructure security level.

Garlic puree turns green easily during the storage. And temperature is one of the greatest affects on degree of greening of garlic puree. The greening of garlic purees was evaluated by sensory analysis. It showed that 35°C was the best temperature to prevent garlic from greening. At the same storage time, different kinds of garlics were at different degree of greening. Organic garlic didn’t show absolutely advantage at preventing garlic from greening.

Composite materials (also called composition materials or shortened to composites) are materials made from two or more constituent materials with significantly different physical or chemical properties, that when combined, produce a material with characteristics different from the individual components. The individual components remain separate and distinct within the finished structure. The new material may be preferred for many reasons: common examples include materials which are stronger, lighter or less expensive when compared to traditional materials. Composite materials are generally used for buildings, bridges and structures. The most advanced examples perform routinely on spacecraft in demanding environments.

Polyether-modified polysiloxane was synthesized by hydrosilylation, using allylic alcohol polyether and polysiloxane as materials, toluene as solvent and chloroplatinic as catalyst. The effect of technology conditions on conversion rate of hydrogenous silicone oil was discussed and chemical structure of product was characterized. The results show that the optimum technology is: the reaction temperature is 95°C, time is 5h, the molar ratio of polysiloxane to polyether is 1:1.2, the dosage of catalyst is 30ug/g and the mass fraction of the toluene is 25% of the system.

Enterprises of freight transport on a special route have to own alliance cooperation system with high efficiency in order to build alliance of freight transport. Selecting cooperative partners is the basis for establishing an efficient transportation system. The paper firstly analyzes the principle of selecting cooperative partners of freight transport alliance on a special route, summarizes the indicator system of selecting cooperative partners of freight transport alliance on a special route, establishes analytic hierarchy process model and finally proves the model with examples.

The farmland soils around three typical livestock farms in Jilin province were studied to elucidate the impact of farms on heavy metal pollution in surrounding farmland soils. The results showed that the average content of Cd was maximal in the soils around cattle farm (0.29 mg kg-1); the average value of Pb was highest in the soils around the pig farm; and Cu, Zn, Ni and Cr were all highest in the soils around the chicken farm. The distribution of heavy metals in the soils around different livestock farms varied greatly. The contents of Cu, Zn, Ni and Cr decreased in the same order: chicken farm> pig farm > cattle farm, but Pb was pig farm> chicken farm> cattle farm, and Cd was cattle farm> pig farm> chicken farm. These results indicated that the livestock farms did not cause significant heavy metal pollution in its surrounding agricultural soils, but the accumulation of heavy metals caused by farms should arouse the attention.

The fire retardants were used in epoxy resin (EP) to get fire retardant EP, whose kinetic parameters activation energies (Ea) were calculated by Ozawa integral method and the Kissinger differential method. The results show that the correlation coefficient (R) is above 0.95, which shows good reliability of the two methods for solving Ea. E for the fire retardant foam is decreased by 40 kJ·mol-1, which shows that the fire retardant can catalyze decomposition and carbonization of EP.

Wood has been treated with amino resins and amino resins modified with phosphoric acid to impart flame retardancy. The thermal degradation of samples has been studied by thermogravimetry (TG) in air. From the resulting data, kinetic parameters for different stages of thermal degradation are obtained following the method of Broido. For the decomposition of wood and flame retardant wood, the activation energy is found to decrease from 122 to 72 kJmol-1.

To solve the problem that traditional automatic image clipping method is on the basic of simple principles, such as fixed size and fixed location, an improved arithmetic based on face recognition is proposed. Firstly, the face region is located by face detecting.Then according to the proportion of face area in the selected region on the template image,the clipping region size of the image to cut is matched.At last,through the relative position of the face center in the template image,the cutting position can be got. The experimental results show that this algorithm can achieve better clipping effect.

Text classification presents difficult challenges due to the high dimensionality and sparsity of text data, and to the complex semantics of the natural language. Typically, in text classification the documents are represented in the vector space using the Bag of words (BoW) technique. Despite its ease of use, BoW representation does not consider the semantic similarity between words. In this paper, we overcome the shortage of the BoW approach by applying the exponential kernel, which models semantic similarity by means of a diffusion process on a graph defined by lexicon and co-occurrence information, to enrich the BoW representation. Combined with the support vector machine (SVM), experimental evaluation on real data sets demonstrates that our approach successfully achieves improved classification accuracy with respect to the BoW approach.

Accurately estimating the deformation of high-rise building is a very important work for surveyors, however it is very difficult to get an accurate and reliable predictor. In this paper, artificial neural network has been applied here because of its good ability of nonlinear fitting. On the basis of the high-rise building monitoring data, three prediction models including the BP, RBF and GRNN neural network prediction models were established, the comparative analysis for the prediction accuracy of the three models was obtained. The results show that neural network is capable for prediction, and GRNN possess higher capability in prediction and better adaptability in comparing with other two neural networks.

This study employs a rapid, energy frugal and environmental friendly method to synthesize nitrogen doped titanate nanotubes (NTNTs), and uses TEM, XRD, Raman, Nitrogen adsorption-desorption isotherms analysis, and UV-vis spectroscopy to characterize the obtained NTNTs. TEM results indicate that NTNTs retain a tubular structure with a crystalline multiwall and have a length of several hundred nanometers after nitrogen doping. XRD findings demonstrate that the crystalline structure of NTNTs was dominated by anatase, which is favored for photocatalytic application. The Ti-O-N linkage observed in the XPS N1s spectrum is mainly responsible for narrowing the band gap and eventually enhancing the visible light photoactivity. After sintering at 350 °C, the UVvis absorbance edges of NTNTs significantly shift to the visible-light region, which indicates N atom doping into the nanotubes. Photocatalytic tests conclude that the NTNTs shows good efficiency with visible light response.

With expansion of enrollment scale, many universities make a large-scale expansion of their campus in recent years, which has caused a series of ecological problems, such as excessive occupation of land, destruction of local ecological environment. It is necessary to provide ecological level assessment and guidance for this eco-campus construction. Based upon the present related research at home and abroad and according to the basic principles of ecology, we have given a clear definition of ecological campus after considering the functional requirements for university campus at first, and then build an ecological campus evaluation index system in which the landscape ecology and the ecological footprint theory have been combined and clear the scoring method of each index. The index system includes five aspects: campus environmental quality, pollutant emissions, resource allocation and utilization, humanity landscape and greening, environmental awareness and environmental education. Furthermore, the analytic hierarchy process (AHP) is applied to this system to obtain the relative combined weights of every index which has passed the combined verify of coherence. Then the multi-factor comprehensive evaluation method was adopted to calculate ecological level index of eco-campus. At the end of this paper the main campus of Jinan University has been taken as an example application analysis of the index system.

The paper analyzed the necessity of PPP governmental supervision game on the basis of existed infrastructure government supervision and analyzed the policy, market and public benefit risk of private sectors, whereupon determined the setup of framework for PPP program government supervision. Supervision will mainly cover the following items: market access; service quality; service price; external supervision; social fairness etc. Lastly, the paper established ethnic risk model of private sector, and came to the following conclusion: degree of ethnic risk is positive correlated with the additional revenue from evil conduct y and market interest rate r, and is negative correlated with the reward from franchised business W, possibility of discovering evil conduct Po, fines derived from punishment of evil conduct D, term of franchised operation t, period of default i and reward declining amount x.

The highly ordered mesoporous MCM-41 was synthesized and modified with various content of aluminum (0-15%) using an incipient wetness impregnation technique. The prepared Al modified MCM-41 materials were characterized by XRD, and explored as adsorbents for arsenic(V) removal. Al loading and calcination temperature played significant roles in the absorbents structures and adsorption capacities. The maximal arsenic(V) adsorption capacity of 16.3 mgAs/gAl was obtained when Al loading of 10 wt% and calcination temperature of 400 °C were used.

The surface tension, CMC, HLB, emulsifying ability and hydrolytic stability of the polyether-modified trisiloxane surfactants were tested. The hydrolytic stability of different products was compared.

In this paper, based on the ultrasonic dispersion principle, the grafting reaction of maleic anhydride (MAH) onto solid PP in water was studied with acetone as the phase physiognomy solvent, ammonium persulfate [(NH4)2S2O8] as the initiator. The influence of specific surface area on the graft ratio was also studied. The results showed that the grafting reaction had obvious relationship with the specific surface area of original PP particles.

In order to solve the problem that the traditional cooling system cannot adjust the cooling water temperature to the different operation conditions of diesel engine, the auto-control cooling system is designed. Using it, the coolant temperature can be adjusted automatically by the single-chip which controls the transducer-controlled pump and the electronic dividing valve which replaces the thermostat. We use the thermal equilibrium bench to verify the figures, and the result is show that using the exhaust of generator heats the cooling water can shorten 13 minutes in starting process and the cooling water temperature adjusted automatically to the changing operation conditions of iesel can decrease the fuel consumption remarkably, the highest fuel saving rate reached 5.4%, the averagely fuel saving rate reached 3.6%.

In order to prepare special alcohol-soluble polyvinyl butyral (PVB), the reaction condition was explored in this paper after analyzing the molecular structure of PVB. Under a simple and economical condition, PVB with 14.2% of butyraldehyde group and good alcohol-solubility were prepared, the PVB film forms quickly after the volatilization of ethyl alcohol, and it has good diaphaneity, high tensile strength, and excellent mechanical properties. The highest tensile strength of the PVB film reaches 50.9MPa, which can meet some requirements of many applications.

This research presented the kinetic performance of arsenic absorption by mesostructure SBA-15 functionalized with Al2O3. The SBA-15 was previously synthesised and subsequently functionalized via impregnation of alumina oxides. The absorption of arsenic(V) was studied as a function of absorbent dosage and contact time. The experimental data were fitted to kinetic pseudo-first order, pseudo-second order and the intra-particle diffusion model. The pseudo-second order model presented the best correlation with the experimental data. Both surface absorption and intra-particle diffusion were acting during arsenic uptake, except for absorbent dosage of 0.1g, which was mainly controlled by the intra-particle diffusion.

A basic engineering cost management system is basis about the engineering cost management for national or regional. As the main basis of engineering cost is determined by two factors are engineering quantity and unit price, so the basic engineering cost management system should reflect the management and control model in the project of "quantity" and "price" of these two aspects in any country or region.

The change law of gel time of calcium carbonate-acid water glass grouting material with the content of calcium carbonate is researched in this paper. But the gel time does not increase evenly with reduction calcium carbonic reducing. It increases suddenly because there is sudden exceeding range with the solution pH value increasing. Meanwhile, the change relation of strength of pure gelation with suitable gel time and time is measured. Firming sand strength experiment is conducted by the better mixture ratio. The strength of pure gelation body increases with the time and the content of calcium carbonate increasing. It is closely related with the reaction mechanism of calcium carbonate-acid water glass. The active Ca2+in this system can react with a series of silicate ion to form silicate precipitate which is filled with colloid and forming skeletonation. And the correlation between firming sand strength and the calcium carbonic acid content is non-significant. Finally, the contrast test of the water glass-glyoxal is done, which is the preparation for the subsequent engineering application.

Based on the PLC control technique and WinCC configuration technology,the control system for the liquid level of the tank was designed. After receiving liquid level signal that transferred from radar tester,the PLC process it ,and then output related control signal to the actuator.The actuator is composed of two AC motors,one is for the main pump ,and another for the auxiliary pump.The function of human-machine interface is achieved with the help of Smart700 touch screen of Siemens.Communication functions between the WinCC project and the PLC site and pictures of the control process which enabals real-time monitoring of the entire system are finished by designing configuration.Finally,the validity of the system and the feasibility of the design have been proved by debugging and the use of enterprises.

This paper proposes the classification algorithm of news pages based on domain Ontology. In order to improve the shortage of current classification algorithm that only considers the content similarity, this paper presents the semantic classification method which considers both content similarity and structural correlation. Firstly, it parses the Ontology to get Ontology category vector, extracts keywords of news pages texts and drops semantic dimension. At this time, finding out the same vocabulary and ontology category vector in page texts to constitute the text expectation vector, and then calculating the content similarity between ontology category vector and expectation vector of text by using the law of cosines. Secondly, the common vocabularies are mapped to the ontology hierarchy chart, and the structural relevancy is obtained by calculating weighted path of this directed acyclic graph. Finally, it calculates the correlation degree of the news pages and Ontology by combining both, and determines the category of news pages by judging the size relationship between the result and the initial threshold value.

We demonstrate a swept-source OCT system based on a polorization-dependent semiconductor optical amplifier (SOA)-enabled Fourier Domain Mode Locked laser (FDML). The broad bandwidth and high saturation power of the semiconductor optical amplifier enables single semiconductor optical amplifier operation with enough bandwidth and output power. The FDML generates ~32mW output power at 45kHz sweep rates, with a tuning range of 115 nm centered at 1326 nm. Using the SOA-enabled FDML laser, ~12.9μm axial resolution,9μm transverse spot size and 105dB sensitivity are achieved. OCT imaging of biological sample is also demonstrated.

After background modeling and segmenting of moving object for surveillance video, this paper firstly presented a noninteractive matting algorithm of video moving object based on GrabCut. These matted moving objects then were placed in a background image on the condition of nonoverlapping arrangement, so a frame could be obtained with several moving objects placed in a background image. Finally, a series of these frame images could be achieved in timeline and a single camera surveillance video synopsis could be formed. The experimental results show that this video synopsis has the features of conciseness and readable concentrated form and the efficiency of browsing and retrieval can be improved.

This paper introduces a traditional method of concept extraction. Considered some defects which this method will miss some concepts having synonyms and the relationship of “is-a”. It gives the improved algorithm to extract them. The result of the experiment shows the feasibility of this method.

The offshore wind turbine (OWT) tower is the important support of the whole wind turbine components, it is necessary to design and research the tower reasonably in order to ensure reliable operation of the OWT. In this paper, 3MW OWT tower is chosen as the object of study. A gas-liquid-solid model of the OWT tower and its external environment is built using COMSOL Multiphysics software. Combined with the two-phase flow theory of gas-liquid, loads of the tower under the coupling action of wind and wave are computed, which provides a new direction for the load analysis of the tower. The results calculated by this method are closer to the physical truth, which provides a more reliable basis for analyzing the fatigue life of the tower further.

In this information society, the traditional method of ontology construction can’t meet the demand for researchers. Because it’s a difficult task to build ontology by hands. The research of automatical construction of ontology is still in the primary stage, especially in the law field. Considering the above condition, this paper gives a Research on Ontology Construction Automatically in the Law Field; we put forward the method of using LLR formula in the step of term abstraction to improve the precision and applying K-means clustering algorithm to obtain better relations of concepts hierarchy. Compared with the approach of constructing ontology by hands, it gets better effect on the law ontology.

The adsorbent was prepared from peanut shell by using Zncl2as activating agent, copper in aqueous solution was used as the adsorbate, the influence of pH, adsorbent dosage, temperature, contact time were investigated through dynamic tests. Then the kinetics of modified peanut shell was studied. The results showed that the modified peanut shell had maximum adsorption efficiencies when the pH was 6; the dosage was 0.2g; the temperature was 25°C and the contact time was 12h.By substituting experimental data into kinetics models, quasi-second-order kinetics model could better describe the kinetics of modified peanut shell adsorbing Cu2+.

The photovoltaic(PV) generation model and the wind power generation model are introduced in this paper. Taking the best economy and reliability of system operation as the objective functions and the system power balance and battery storage performance indices as the constraints, the optimal capacity of battery energy storage can be determined with the Tabu search algorithm. With the example system, the simulation results show that the proposed models and the algorithm are correct.

Based on the proposed efficient cyclic correlation estimator by exploiting normalized infinite norm, this paper develops a robust adaptive time delay estimation method which provides additional robustness against heavy-tailed noise and when the noise statistics are not fully known. Simulations demonstrate the reliable and robust performance of the proposed cyclic correlation estimator and its corresponding time delay estimation algorithm.

Jianli Reach has long been exposed to labile main flow and the frequent translocation between the main channel and the lateral branch. To investigate how the long-term process of flow-sediment influences the adjustment of river channel pattern, monthly time series (1951-2009) of runoff and sediment load at Jianli hydrological station of Yangtze River were analyzed using three methods: R/S analysis to estimate Hurst exponent, Mann-Kendall method and the time series anomaly analysis. The result shows that on 1 year time scale, the values of Hurst exponent are indicating persistence, that is to say, the trend of runoff and sediment in the future will generally be the same as the past, and the persistence in runoff series is stronger than that in the sediment load. The period of oscillation in annual runoff and in sediment load is about 30 years. The result of Mann-Kendall test shows an abrupt change point of runoff time-series at 1967 and an abrupt change point of sediment load time-series at 2003. And during the flood season, the values of Hurst exponent still indicate persistence, which is weaker than that in whole year correspondingly.

Kernel is a key component of the support vector machines (SVMs) and other kernel methods. Based on the data distributions of classes in the feature space, this paper proposed a model selection criterion to evaluate the goodness of a kernel in multiclass classification scenario. This criterion is computationally efficient and is differentiable with respect to the kernel parameters. Compared with the k-fold cross validation technique which is often regarded as a benchmark, this criterion is found to yield about the same performance with much less computational overhead.

This paper reports the adsorption of Cr(VI) ions from aqueous solution by organic-inorganic hybrid mesoporous material. Adsorbents were prepared with the DTAB,TTAB,CTAB and STAB for organic component synthesis organic-inorganic hybrid mesoporous material(HM), namely HMD, HMT, HMC and HMS. The best adsorption hexavalent chromium experimental conditions is obtained after having orthogonal experiment.

In real estate industry, there exist some contradictions, including less land supply and higher residential demand, high residential vacancy rate and growing residential demand, resource waste owing to short-term investment and limited resources, high prices and low purchasing power. The paradox matter-element extension theory is fit for the contradictive study, and consistent with the sustainable development of the real estate industry in terms of research subject, logic theory, and variability. On basis of these, this Study establishes extension-theory-based evaluation index system for sustainable development of real estate industry, in which the indices are categorized into five groups: economy and finance, social equality, ecological environment, resources utilization, and government management.

This paper addresses the stabilization problem for a class of switched nonlinear systems with Lipschitz nonlinearities using the multiple Lyapunov functions (MLFs) approach. A state feedback controller and a state dependent switching law are proposed to asymptotic stabilization the switched system via linear matrix inequalities (LMI). The developed control strategy ensures asymptotic stability of the closed-loop system even if the nonlinear part . Finally, the feasibility of the proposed method is illustrated through a simulation example

This paper studies the speech enhancement technology. A Lyapunov function of the tracking error systems is defined, and the adaptive filter based on FXLMS algorithm can make the error converge to zero asymptotically. It is shown to be suitable to solve the problem of the speech enhancement from computer simulations

This paper describes the procedure of a hybrid approach based on grey model and artificial neural network (GM&ANN) to analysis and forecast of deformation data. The GM&ANN is formulated into three steps:(1)according to the monotonously increasing characteristics and the nonlinear characteristics of deformation time series, total deformation can be divided into tendency part and stochastic part.(2) use GM(1,1)to fit the trend of the data and obtain the residual series, on this basis by using artificial neural network to fit the stochastic part (residual series) .Then the forecasting value of deformation is obtained by adding the calculated predictive displacement value of each sub-stack. (3) validate the model. The results of experiments show that this hybrid has higher performances not only on model fitting but also on forecasting and therefore can be applied to deformation data processing.

In this paper the hydroxyapatite fibers reinforced chitosan nanocomposites with high hydroxyapatite dosage (70~90 wt%) were synthesized by in-situ hybridization. The semi-permeable membrane was used to control the process of hybridization and morphology of hydroxyapatite. The compositional and morphological properties of nanocomposites were investigated by FTIR spectroscopy, X-ray diffraction, and transmission electron microscopy. The results showed that the hydroxyapatite were carbonated nanometer crystalline fibers with high aspect ratio (about 25) and dispersed uniformly in the nanocomposites. The high-resolution image indicated that the growth of nano-hydroxyapatite crystallites in the chitosan matrix preferred in the c-axis. The mechanical properties of these nanocomposites were enhanced dramatically and the compressive strength increases almost to 170MPa when the hydroxyapatite content is 70 wt%. The in vitro tests indicated that the composites have high bioactivity and degradation. These properties illustrated the potential application of this kind of nanocomposites for bone tissue engineering.