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t is a tough work to select accurate web pages for search engine. This paper applied a semantic parsing model into search engine by comparing the conceptual structures between users input and text. The words, sentences and sentence groups can be mapped into conceptual symbols, semantic categories, and contextual elements based on the theory of Hierarchical Network of Concepts. The approach will improve the intelligence and flexibility of the search engine in future.

Recently, wireless sensor networks (WSNs) have attracted a lot of attention from the network research community, especially in the aspect of event-driven wireless sensor networks (EWSNs), such as adversary locating, fire detection and so on.As the nature of importance of event monitoring, security has to be assured in both of communication and processing. However, due to the inherent resource constraints, security inEWSNs is faceddifferent issues and challenges than traditional WSNs.In this paper, we attempt to give an outline on the security issuesin the EWSNs. And then we propose a new secure architecture for it, which covers potential security issues. In this architecture, we analyze the possible threats and give out the correspondingcountermeasures.

With the rapid developing of wireless communication technology and the growing user service, the demand on the system capacity from users is growing. In the LTE network, the uneven load distribution makes that network resource is not fully utilized, which results that the capacity is limited. In this paper, a novel optimizing mechanism of network load balancing based on the network manager is proposed. The eNBs in the network will broadcast the current load status by the way of adapting a new message format with the life cycle bit when the load of the cell is changed, then the serving eNB can decide which part of users in the cell should transfer to the neighboring cells and send a request to the network manager. The network manager will calculate whether the transferred users make the neighboring cell load exceed the threshold. If not, the users can be transferred to the neighboring cell and release the serving cells load burdon. Otherwise, the serving cell will search other neighboring cells to transfer the users. The simulation results show that the proposed mechanism will not consume more network resource and improve the network throughput significantly.

Traditionally, enterprises have approached IT modernization and back office process enhancement in silos, by introducing multiple vendors with different technologies, platforms and operating systems, which limits process integrity and leads to disseminated responsibilities. In contrast, the Cloud revolution has made it much easier for enterprises to approach business transformation in a holistic manner, leading to a quantum leap in their business and IT practices and performance. In other words, Cloud-based workflow (which is shorted for cloud workflow) technology is now regarded as a pretty good solution: Cloud workflow helps organizations in process harmonization, optimal organization design and change management offering benefits beyond cost reduction, it enables a complex application instance to be abstractly defined, flexibly configured and auto-operated. This paper introduces shortly the technology of both cloud computing and workflow and then presents the concepts and features of cloud workflow. Meanwhile, the following part discusses the application scenario and the application cases of cloud workflow. Lastly a possible trend of workflow in the future is proposed.

Cellular automaton (CA) has been widely investigated as random number generators (RNGs). However, the CA rule and the number of neighbors must be chosen carefully for good randomness. In Ref. [11], non-uniform CA with next nearest neighborhood was applied to generate a pseudo-random sequence. Considering that non-uniform CA has more complex implementation in hardware and needs lager memory to store different rules than uniform CA. In this paper, we propose new RNGs based on uniform CA with next nearest neighborhood. Time spacing technique and NIST statistical test suite are used to find optimal rules for uniform CA. Experiment results show that the sequences generated by uniform CA with optimal rules successfully passed all tests in the NIST suite.

Semantic Web application is the application of semantic Web technology, of which the data containing semantic, thus is able to support the knowledge understanding and the knowledge processing. It can share information and refine information dynamically through the Internet access, which makes more full use of the existing Web resource on the Internet. In this paper, the definitions of semantic Web application as well as the structure and properties are formulated. A semantic Web development model is constructed with reference to the Web application development model.

The aliasing due to subsampling and the blur from the finite detector size can decrease quality of the images and make fine details and structures difficult to interpret. High resolution images can be reconstructed from several adjacent frames in a sequence by reconstruction process. This paper describes the high resolution image reconstruction method based on wavelet domain. In this approach both the image sequences and the degradation operator are presented by orthogonal wavelet with compact support. Experimental results demonstrate that the proposed method is effective to improve image details.

This paper describes a cycle in which organizational learning and software development serve each other, presents the concept of organizational learning cycle method. Experience in a real software development project has led us to identify several key challenges for software design and development through organizational learning. A discussion of these challenges presents steps taken toward addressing them, as well as barriers remaining. Keywords-Organizational learning, Group memory, Systems design, Collaborative work

In this paper, through specific description of the concept of virtual private network VPN, operating principles and the IPSec protocol, and using the OPNET software for performance simulation of IPSec VPN network, we get the result of IPSec VPN throughput of the network, which is unstable. o though IPSec VPN has improved the safety performance of data transmission, it at the same time affects the transmission efficiency. By analyzing the problems of IPSec VPN, in terms of improving safety performance, the combination of PKI and IPSec VPN program was proposed. Theoretical analysis shows that such program can indeed solve the problem of authentication imperfect, thus improving the safety performance of the network.

With the development of component technology, component granularity plays a very import role on the complexity of component composition. How to assemble the component of big granularity? How to make the component in the same domain integrated? Application framework brings the new era of software-reused technology. But how to construct application framework to make it higher reuse? According to the current research of application framework, the paper gives a hierarchy model; The model divides application framework into several layers. Different application framework in different layer has different solutions and the higher the application framework stands in, the lower the probability of change is.

This paper presents a hybrid algorithm for the hot rolling scheduling problem, which is derived from the actual steel production, and some features make the solution methodology more difficult. The hybrid strategy is based on the solution construction mechanism of estimation of distribution algorithm (EDA) with path relinking (PR), an evolutionary method, which results in a novel approach that we call EDA_PR. Moreover, a decision support system in which the algorithm has been embedded for the hot rolling scheduling is designed. The computational experiments show that the EDA_PR method has more potential for improvement to solve the hot rolling scheduling problem compared with the manual scheduling method.

Android is one of the most popular smart phone and tablet platforms; Zigbee is the standard for home automation and will play an important role on future WPAN. Enabling the Zigbee communication on Android can exploit the rich network and nice display power of the Android phone in Zigbee applications. In this paper we present our work on integrating CC2530 into an Android smart phone. Based on JNI library, the software is developed to enable Android system can control the CC2530 module insides. The firmware in CC2530 is also discussed. The test is carried on with the configuration that an Android smart phone communicates with a standalone CC2530 node via Zigbee radio. The test verified the design feasibility. Keywords-Android devices, zigbee networks; JNI library; wireless networks

The parameter bw is a distance bandwidth between 0 and 1 in harmony search algorithm, which helps the algorithm in finding globally and locally improved solution. In this paper, a new harmony search algorithm is proposed in order to improve the convergence speed and the global search algorithm of the harmony search algorithm. The parameter bw is adjusted based on cloud theory in this new algorithm. The new algorithm is tested on some benchmark functions and the results are compared with the result of the traditional harmony search. Experimental results indicate that the new harmony search algorithm has a good performance in the global search ability and convergent speed.

Network externality is a vital characteristic of the products in economics of networks. Network congestion will lead to negative network externality when digital products are communicated in the net. It will effectively decrease the negative network externality via developing a suitable pricing mechanism. This paper begins with the utility of a single user and that of the whole network to build a network congestion utility model to analyze it. As TCP connection has an autonomous congestion-detecting mechanism which can increase the utilization of network resources, we regard the TCP connection pricing as the basis of our research.

The form of fruit fly optimization algorithm (FOA) is easy to learn and has the characteristics of quick convergence and not readily dropping into local optimum. This paper presents the optimization of RBF neural network by means of FOA and establishment of network model, adopting it with the combination of the evaluation of the mean impact value(MIV) to select variables. The validity of this model is tested by two actual examples, furthermore, it is simpler to learn, more stable and practical. Keywords-FOA; RBF neural network; Parameter optimization; MIV; Variables screen

Server virtualization is to create and run several independent operation systems at the same time to maximize the utilization efficiency and flexibility of IT resource, the most serious security problem of which, however, is the unauthorized access of unsafe virtual machines. This paper presents a SELinux-based secure server virtualization method against the issue. With SELinux access control, virtual machine process is isolated from system processes by setting up different type labels and access control policies. Whats more, different virtual machine processes can be independent with each other by introducing Multi Category Security (MCS) protection mechanism, thus to achieve secure access of server virtualization. Finally the realization of the method is presented.

One fundamental task of wireless sensor networks (WSNs) is to save sensor power, and try to prolong the lifetime of WSNs. Traditional routing protocols are almost based on homogeneous WSNs, all sensors are use single hop or multi-hop to transmit data to base station, which lead to overload sensors next to base station, thus appear energy hole and made WSN outwork. In this paper, we use a new novel mobile collectors mobile strategy method to prolong network lifetime, and reduce hot-spot effect around base station. We propose the routing method can effectively balance the network sensors energy depletion, more save energy and longer whole network lifetime compare to LEACH.

Under the study of Kernel Methods, this paper put forward two improved algorithm which called R-SVM & I-SVDD in order to cope with the imbalanced data sets in closed systems. R-SVM used K-means algorithm clustering space samples while I-SVDD improved the performance of original SVDD by imbalanced sample training. Experiment of two sets of system call data set shows that these two algorithms are more effectively and R-SVM has a lower complexity.

This paper puts forward a model combined cloud computing and P2P, and then achieves chord resource search algorithm in the model. Because chord algorithm one hand, does not consider the problem of node heterogeneity, on the other hand, its routing table has large redundant information. So chord algorithm is improved from the two areas, and last MRC-chord is proposed. The algorithm first defines that the nodes of the same geographical form a ring, and in each ring, the node with strongest overall performance is selected to be super cloud node, all of the super cloud nodes form the master ring , then improves routing table. Experimental results show that: the improved algorithm can reduce average routing hops and average network delay effectively, so improves the efficiency of resource search.

As an important commercial application, E-commerce is widely used with the development of Internet technology. However credit disks block the progress of E-commerce in the non-standard market environment, Analyzing credit management modes such as eBay and Taobao, this paper proposed a new credit calculation formula and construct a credit evaluation framework, in order to improve trading success rate, to avoid commercial fraud, and to contribut information construction of China.

A wireless ad hoc network is a self-configuring infrastructurelessh network of mobile devices connected by wireless. In order to support the basal networking functions like routing and packet forwarding, the nodes in wireless ad hoc network should be cooperate with each other due to the limited range of wireless transmission. However, nodes are unwilling to relay packets for others considering the poor energy and bandwidth especially in the open community environment. Some approaches to stimulate nodes cooperation have been introduced recently. In this paper, we provide a novel method based on cross-layer design to solve the cooperation issues both in Mac and network layer. The method with the help of reputation mechanism and utility function based on game theoretical approach can promote nodes to cooperate and make the whole network to reach Nash equilibrium.

More and more organizations and individuals outsource their storage and computing business into cloud computing, which is a representation of a movement towards the intensive, large scale specialization and economy. Cloud computing brings about convenience and efficiency, but challenges in the areas of data security and privacy protection. This paper identifies the most vulnerable security threats in cloud computing, which will enable both end users and vendors to know about the key security threats associated with cloud computing, and to know about critical analysis about the different security models and tools proposed. Key security strategies from the infrastructure, operation and security incident response relieve the common security issues of cloud computing.

With the integration of informatization and industrialization, the application of software is getting more and more extensive and plays a powerful role in many facilities. At the same time, Software failures cause tremendous losses, thus ensuring the reliability of software becomes increasingly important. The basic conceptions of software reliability are put forward in this paper, and comparative analysis on the research status at home and abroad are studied. Meanwhile, the perspective of the further progress of software reliability is made.

This paper proposed a framework and an algorithm for identifying communities in dynamic social networks. In order to handle the drawbacks of traditional approaches for social network analysis, we utilize the community similarities and infrequent change of community members combined with community structure optimization to develop a Group-based social community identification model to analyze the change of social interaction network with multiple time steps. According to this model ,we introduced a greed-cut algorithm and depthsearch-first approach and combine them to develop a new algorithm for dynamic social interaction network recognition (called ADSIN). In addition, we conduct experiments on the dataset of Southern Women, the experiment results validate the accuracy and effectiveness of ADSIN. Key words-social network; community recognition; time step; φ

Cloud computing has changed people's work, life and learning while more and more collaborative learning based on cloud services are applied to the field of education and teaching. This paper analyzes the collaborative learning characteristics supported by cloud computing and designs collaborative learning programs of College Computer Basis based on cloud services.

This paper combined with computer graphics and related spatial information sciences technologies, made use of the software Vega Prime, On the basis of three-dimensional modeling of Nanchang HangKong University campus, built a campus three-dimensional visual simulation software, which can achieve the campus landscape, zoom, rotation, scaling, flight roaming and static and dynamic simulation capabilities, such as the fountain, lake, pedestrians, vehicles, etc. The use of this technology has great importance on school enrollment, employment, education, alumni relations, showing the school strength and other aspects.

Data island exists in most of the information system. And the system platform integration could eliminate the existence of the information island. This paper visited database information system through the EJB component technology, and using the metadata way to extracted data information from the heterogeneous database system, and it realized sharing information between the heterogeneous database system. In this system the B/S mode structure and EJB component technology, improve the system usability and expansibility.

Based on the ant colony algorithm analysis and research, this paper proposed an improved ant colony algorithm. Through updating pheromone and optimal search strategy, then applied to the Traveling Salesman Problem (TSP), effectively improved the searching capability of the algorithm. Finally through the simulation testing and analysis, verified that the improved ant colony algorithm is effective, and has good performance.

The monitoring of timber structures exposed to natural climate fluctuations during their service life is an important topic for both their serviceability and safety. Numerical methods based on the recent advances in hygro-thermal modelling of wood can integrate the usual sensor-based monitoring techniques by reducing the maintenance costs for timber structures. In this paper, a 3D full coupled analysis based on the multi-Fickian theory with sorption hysteresis of wood is implemented in Abaqus FEM code by defining a new finite element in a user subroutine. To verify the method, the hygro-thermal behaviour of a glulam beam tested in laboratory under variable humidity within a previous research is analysed and the numerical values of moisture content are found to be in agreement with the experimental data. Furthermore, a numerical case-study of a glulam cross section under real climate variations is presented and the related results show the capability of the method to predict the moisture states in each points of the glulam member under continuously variable humidity and temperature.

Electronic business activities of enterprise are changing the value creation process on every link of enterprise supply chain based on the rapid development of information technology. Constant innovations of electronic business model has had a powerful impact upon the traditional business model, and produced complicated influences on ERP platform interface of the enterprises and suppliers. Based on the value chain perspective, this paper makes data analysis by applying panel data model to electronic business model and enterprise informatization construction situation. The results show that the information construction of the case enterprise has promotive effect in analyzing the profitability of B2B, BMC and B2G models. Enterprise's information construction has limited positive facilitation to B2C mode, and negative effects may emerge because of cost problem. Keywords-Electronic commerce mode; Value chain; Informatization construction

Computer network generate a spatial and temporal separation in teaching activities, the new feature of the online teaching also make it possible to improve students' learning efficiency by using of the theory of interactive activities and appropriate teaching strategies. This paper mainly discuss the problems exist in distance teaching system based on the Internet, and design an prototype model for distance teaching which could achieve a unified and efficient management of curriculums, teachers, students and teaching resource according to the specific requirement of school.

Multi-agent formation control is the process in which the teams formed by multiple agents move to specific target or specific direction. The formation method of the linear formation and circular formation are given in this paper, based on the geometric characteristics of the formation formed by multi-agent. The process in which 5 agents arrived at the designated target point and formed a linear formation is achieved through simulation; and 4 agents formed a circular formation and cooperated to carry heavy weights. The result of the three-dimensional simulation shows the feasibility of the method to form multi-agent formations in different environments and different tasks.

The classical mean shift (MS) algorithm is the best color-based method for object tracking. However, in the real environment it presents some limitations, especially under the presence of noise, objects with partial and full occlusions in complex environments. In order to deal with these problems, this paper proposes a reliable object tracking algorithm using corrected background-weighted histogram (CBWH) and the Kalman filter (KF) based on the MS method. The experimental results show that the proposed method is superior to the traditional MS tracking in the following aspects: 1) it provides consistent object tracking throughout the video; 2) it is not influenced by the objects with partial and full occlusions; 3) it is less prone to the background clutter.

On the analysis of logistics information collecting techniques (including the Unified Information System, The Internet Of Things, Global System for Mobile Communication ), the paper puts forward solutions and innovative ways to operate the system based on Unified Information System (UIS) in The Internet Of Things (IOT). GSM information collection, which is based on the UIS, has integrated the technologies of Radio Frequency Identification (RFID), GSM, and Computer Telecommunication Integration (CTI). With the unique characteristics of business processes of UIS and IOT, the systematic design has carried out the technical construction and interactive system design on the brandboard adjustment program of GSM information collection model, the anti-collision technique as well as Network Communication Program of GMS model controlled by AT command. This design has realized the exchange between the logistics information collection and processing and GSM network by the way of adopting the TC35i Single Chip Processor Control System, as a result, it has formed the distributed link for the logistics information system, and identified the feasibility of GSM information collecting system applied in this system.

Continuous wave (CW) radar and global positioning system (GPS) is the main equipment of trajectory measurement in range. Based on range test background, propose a method to fuse GPS pseudo-range and CW radar range to provide complete trajectory positioning parameters, effectively reduce the impact of the systematic error of the measuring element to improve positioning precision of aircraft orbit solving. Through research on the measurement principle and the practice calculated data is given in this paper. Finally, several famous practical examples and simulation results are presented to illustrate our method efficiently.

The paper discusses the time-domain blind seperation applied to communication signals, using an ICA algorithm EFICA together with a wavelet de-noising processing method. In the Blind source separation system, regardless of the mixed signals and separated signals, noise pollution occurs frequently, it increases the complexity of BSS and the difficulty of dealing with the aftermath. So an automatic method of and wavelet de-noising processing is proposed finally. It yields good results in the experiment and improves the performance of BSS system.

Local image information is crucial for accurate segmentation of images with intensity inhomogeneity which usually occurs in medical images. However, image information in local region is not incorporated in popular region-based active contour models, such as piecewise constant models and piecewise smooth models. In this paper, a method which is able to use local information is proposed. The main point is the introduction of the local fitting information expressed by a kernel function which is crucial for segmentation. Our method is based on piecewise constant Chan-Vese model, and compare with different methods for several synthetic images and medical images. KeywordsGACM, mediccal image segmentation, intensity imhomogeneity, C-V model.

In order to develop more energy-saving control algorithm, an electric vehicle air conditioning system model is established. Electric air conditioning system compressor model, compartment thermal load model, heat transfer model, controller model and temperature calculation model are built based on certain pure electric commercial vehicle air conditioning system. A compound control method applying fuzzy and PID theory is put forward in this paper. A secondary development of EV model is established in ADVISOR. As the result shows, the Fuzzy-PID control method is more accuracy and consuming less energy. Optimized control algorithm for air conditioning is realized.

in order to solve the access control system loopholes, can appear the problem of chaotic management, security failure and conflict of competence, this paper studies the access control model, on the basis of the design of a SSL VPN oriented access control system, the authentication module, access control module, role access module and security detection module design. The realization technology of system user identity. This has practical reference significance to the personnel security technology research network.

Currently, mine safety is the focal point in mining activity. As a new and advanced approach for geophysical prospecting, the ground penetrating radar (GPR) is used in the mine disaster detection. Aiming to solve the restriction of low resolution and limited depth of the GPR in the deep coal seam detection, the computed tomography (CT) technology is employed for deep disaster detection in this paper. A large number of coal seam digital simulation model, including different internal diseases, are established, and the simulation data are processed by using the Least Square QR-factorization (LSQR) inversion algorithm, which has the good performance in saving computational time and memory space. Additionally, the influences of iteration precision and grid size on the effect of inversion are analyzed. The inversion results show good agreements with simulation model feature configurations, and the diseases objects can be detected.

The work of the gear transmission is very complex, and its failure in the form and features tend to show non-linear mapping. Fault signal is often submerged in conventional vibration signal and noise, it is not easy using traditional signal processing methods to extract fault features which in a difficult to gear fault diagnosis. This paper based on the genetic algorithm to optimize the structure of the BP neural network model for the intelligent diagnosis system which is used in gear fault diagnosis.The experimental results show that this method can be effectively used for the diagnosis and identification of the gears common fault type. Keywords-Artificial Neural; BP neural network; Gear fault intelligent diagnosis; Vibration Signal

Along with the development of facility agriculture technology, the greenhouse industry constantly upgraded. Applying sensor technology, electronic technology, communication technology and network technology to regulate and control the greenhouse environmental factors will greatly boost greenhouse industry economic benefit. This paper do some research and analysis of monitoring and controlling on greenhouse environment in facility agriculture. Keywords-temperature control; environmental factors; sensors; mode of controlling

Nowadays, microblog has emerged as the most promising social networking service in the Web2.0 age with diverse features for information dissemination, interpersonal communication and many other aspects. Chinese microblog shows great potential owing to the rich marketing source and powerful media influence brought by the huge user population. As the microblog community is largely influenced by some authoritative users, identifying these users and understanding the information dissemination pattern are theoretically and practically significant for us to promote user services, develop further applications and seek commerce opportunities. In this paper, we proposed a modified method for user authority ranking. A user-message graph modified according to Chinese microblog was applied to our study, and an algorithm based on ObjectRank was used to calculate ueser authority scores. We analyzed Sina microblog, as it was the most widely adopted Chinese microblog and more resources for research was accessible.

This paper describes the cold rolling database system based on Web platform and the relevant technology of this system. Adopt tree-tier B/S architecture,ASP.NET technology, C# programming language. By communicating in different data storage of application , a dynamic, execute, interactive, highly efficient network application software has been built. KeywordsCold Rolling Materials; Web Database; ASP.NET; Internet

The paper focuses on the intelligent logistics pallet, networking, traceability information technology and unified logistics information system, and puts forward unified traceability information system of intelligent logistics pallet based on the Internet of things (IOT), displaying innovative system realization method and technical system. IOT intelligent logistic pallet traceability system is an integrated fusion application of RFID, GIS, GPS, computer telecommunication integration together with Internet technology; in system design and implementation, TOT and RFID coupling mechanism, CTI and API interface programming are adopted for construction of three intelligent system service architecture of logistics pallet traceability system including application, business and physics; in the logistics pallet regular operation, reading and writing RFID equipments, labels and telecommunications network, Internet, and other unified information communication mode are fused into the intelligent logistics information system, so as to realize the intelligent logistics pallet identity identification and traceability function. The system test output results indicate that, intelligent logistics pallet unified information system is equipped with intelligent recognition, management and tracing function and business process reengineering capacity including production promotion, distribution, transport logistics and allocation.

In this paper we intend to apply a new method to predict tertiary structure. Several feature extraction methods adopted are physicochemical composition, recurrence quantification analysis (RQA) , pseudo amino acid composition (PseAA) and Distance frequency. We construct the binary tree Classification model, and adopt flexible neural tree models as the classifiers. We will train a number of based classifiers through different features extraction methods for every node of binary tree, then employ the selective ensemble method to ensemble them. 640 dataset is selected to our experiment. The predict accuracy with our method on this data set is 63.58%, higher than some other methods on the 640 datasets. So, our method is feasible and effective in some extent.

Anomaly detection has been a field of intensive research over the last years. Along with that several works to evaluate anomaly detectors have been proposed. In this paper we argue four properties regarding ideal evaluation methodologies that cannot be answered by single current evaluation technique employed today. We therefore present an framework of an evaluation methodology that leverages traces from operational networks, simulation and emulation to satisfy the four properties.

Improved color channel comparison method (ICCCM) is an effective method to transformcolor images into gray-scale ones. Based on the ICCCM, black or white insects could be effectively extracted and recognized from the real color images with bright background. Howeverit is difficult to use the ICCCM to extract and recognize the black insects from the realcolorimage with dark background. In this paper, the ICCCM is modified to transformthe color images into the gray ones, extracting and recognizing the black insectson the dark background. The ICCCM is modified as follows: (1) A threshold of the gray image is an average brightness value ofred (R), green (G) and blue (B) in all the image pixels.(2) The bright pixels and the color pixels have the highest brightness value 255 in the gray image.(3) A pixel brightness value of the dark area in the gray image equals to a minimum of R, G and B in the pixel. (4) After deleted all the pixels with a brightness value of 255, a threshold of the binary image is determined by Otsus theory. The modified ICCCM more effectively extracts and recognizes the black insects from the realcolorimages with dark background compared with the ICCCM.

In this paper, we propose a novel real-time 3D hand gesture recognition algorithm based on depth information. We segment out the hand region from depth image and convert it to a point cloud. Then, 3D moment invariant features are computed at the point cloud. Finally, support vector machine (SVM) is employed to classify the shape of hand into different categories. We collect a benchmark dataset using Microsoft Kinect for Xbox and test the propose algorithm on it. Experimental results prove the robustness of our proposed algorithm.

in this paper, we attempted to find an effective method to resolve multi-satellite observation scheduling problems. Firstly, an acyclic directed graph model for multi-satellite observation scheduling was constructed. Secondly, based on the graph model, we presented a novel hybrid ant colony optimization mixed with the iteration local search algorithm (ACO-ILS) to produce high quality schedules. At last, extensive experimental simulations demonstrated that the proposed ACO-ILS algorithm is very efficient.