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When applying artificial intelligence technology to quantitative trading, high noise and unpredictability of market environment are the first practical problems to be considered. Therefore, how to select the learning features of the market based on rapidly changing financial data is particularly important. In this paper, the real time financial data are first processed by K-line theory, which uses candlesticks as a generalization of price movements over a period of time, so this process can play the role of de-noising. Then, the candlesticks are decomposed into different subparts by mean of a specified spatio-temporal relationship, based on which cluster analysis of the subparts to get the learning features. Further, the learning features that are clustered by the above K-lines are put into the model, and the online adaptive control of the parameters in the unknown environment is realized by the deep reinforcement learning method, so as to realize the high frequency transaction strategy. In order to verify the performance of the model, the data on different financial derivatives transactions such as stocks, financial futures and commodity futures are used. The proposal approach is compared with other methods which are based on price, fuzzified price and K-lines for features learning. In order to verify the accuracy of the proposal approach, prediction-based methods such as recurrent neural network and fuzzy neural network are used for comparison. Experimental results show that the proposed method has higher robustness and prediction accuracy.

In real applications, noises are often present in the obtained data, which would considerably affect the performance of machine learning models. Although support vector machine (SVM) is a classic and efficient learning model, however, it is sensitive to noises in the training data. In this paper, a novel support vector machine named as reconstructed training-set SVM (RTS-SVM) is proposed to implement classification for high-noise data, where the roulette cooperative coevolution algorithm (R-CC) is used to optimize the parameters of RTS-SVM. The proposed SVM model is applicable to make the classification of high-noise data by tackling with the sensitive effect of the ``soft margin'' of SVM on the original training set. By means of the hierarchical relations existing in feature sets, hierarchical grouping (HG) algorithm is applied to construct feature subsets, based on which R-CC coordinates the parameters of RTS-SVM to achieve the optimization of the whole model. The application of the proposed scheme in the classification of financial time series is mainly discussed. Besides, the proposed model is also verified by using synthetic data with high noises and daily life data sets. Examples are provided to illustrate the effectiveness and practicability of the proposed algorithm.

Since the existence of fuzziness in the real world, uncertainty could be always present in the reasoning results. Therefore, how to tackle with the hesitation existing in the process of reasoning is a meaningful issue for the construction of the inference system. In this paper, a novel interval type-2 intuitionistic fuzzy neural network based on long-short term mechanism is proposed (LSTM-IT2IFNN). By means of interval type-2 intuitionistic set, the hesitation of reasoning is described and involved to determine fuzzy rules in inference system, by which the chosen of fuzzy rules not only considers the membership value but also non-membership degree. In order to handle the regression problems with long-term time dependency, long-short term mechanism is introduced into fuzzy neural networks, which can effectively improve the memory ability of long-term knowledge. Furthermore, by means of intuitionistic sets, an extended metacognitive learning mechanism is proposed for the adaptively online learning of network structure, where it achieves when, what, and how to learn from the sequential data. The performance of the LSTM-IT2IFNN is evaluated on different regression problems, including synthetic and real-world data. By comparing to existing algorithms, the experimental results show the efficiency and accuracy of the proposed scheme.

To examine the efficacy and safety ofpersonalized tongxie formulas; to decrease type II errors to minimum.Patients were randomized (1:1:1) into three groups given tongxie, placebo, or pinaverium 3 times daily for 4 weeks. Patients in the tongxie group were treated with personalized formulas based on TCM differential diagnosis, i.e., basic type of IBS, IBS due to liver depression and qi stagnation, excess heat in the liver, deficient spleen function, deficient kidney function, and others (groups 1-6). Primary endpoints were significantly greater reductions in abdominal pain and Bristol stool score. Secondary endpoints were reductions in pain and stool frequencies and abdominal discomfort and its frequency.There were significantly more patients whose stool consistencies were improved than pains were relieved in the entire population (p0.001), but there was no significantly difference in subpopulation group 3 (p0.05). There were significantly more patients whose stool frequencies were reduced than pain frequencies were reduced in the entire population (p0.001), but there were no significantly difference in the subpopulation Groups 1, 3, 4, and 6 (p0.05). Multiple active ingredients and their mechanisms of actions to relieve IBS symptoms were identified.The outcomes in subpopulations may be different from those of the entire population, indicating that personalized formulas are important to achieve optimal outcomes; the active ingredients and innovative mechanisms identified in this study can be the candidates for developing new IBS drugs, and used to manage IBS, respectively.NCT01641224 (www.ClinicalTrials.gov).

The volatility is one of the essential characteristics of financial time series, which is vital for the knowledge acquisition from financial data. However, since the high noise and nonsteady features, the volatility identification of financial time series is still a challenging problem. In this paper, from a perspective of granule complex network, a novel approach is proposed to study this problem. First, numeric time series is structured into fuzzy information granules (FIGs), where the segments of time series in each granule would own similar volatility features. Second, by using the transfer relations among granules, granule complex network is to be constructed, which intuitively describes the transfer processes among the different volatility patterns. Third, a novel community detection algorithm is applied to divide the granule complex networks, where granules with frequent mutual transfers would belong to the same granule community. Finally, Markov chain model is carried out to analyze the higher level of transfer processes among different granule communities, which would further describe the larger-scale transitions of volatility in overall financial time series. An empirical study of the proposed system is applied in the Shanghai stock index market, where volatility patterns of financial data can be effectively acquired and the corresponding transfer processes can be analyzed by means of the granule communities.

The paper presents the effect of exhaust gas and inlet air temperature on thermal efficiency for boiler system. Based on the numerical model, the performance indexes of boiler system are calculated at different conditions using EES (Engineering Equation Software). The results show that when the exhausted gas or inlet air temperature increases 10-15°C, the heat loss of exhaust gas decreases 0.8%-1% and thermal efficiency of boiler system increases 0.8%-1%; The crucial factors that can affect thermal efficiency are exhaust gas temperature and fuel volatile ratio; seven optimized schemes are designed for a case of boiler system. A new methodology is provided for evaluating the efficiency of boiler system.

The paper presents different kinds of optimization scheme of air-condition system based on equipment technologies and variable parameters in Guangzhou. Coefficients of performance (COP) and energy efficiency of rate (EER) are the main index of air-condition system. The results show that the percentage of optimized air-condition systems are of different weight ratio based on analytic hierarchy process method. Pump and compressor frequency conversion technologies and higher indoor temperature are the main energy efficiency measurements for air-condition system. The results provide a new methodology for evaluating the air conditioning system construction.

To mitigate the frequently over-threshold subsynchronous oscillation (FOSSO) phenomenon which occurred in Hulunbuir power plant in the northeast of China, a novel equipment based on voltage source converter (VSC), named subsynchronous oscillation dynamic suppressor (SSODS) is developed and installed. In this study, the root cause of FOSSO is revealed by analysing the response characteristics of the system. Then the control strategy of the developed SSODS is presented. Damping characteristics of SSODS are analysed by the complex torque coefficient method. To verify the effectiveness of the control strategy and the physical controller of VSC, as well as provide initially optimised controller parameters for the field tests, real-time closed-loop tests are carried out. A novel method of torsional modal frequency measure for onsite commissioning test is proposed. The operation and field verification test of SSODS is introduced, and test results demonstrate that SSODS can mitigate the new SSO phenomenon dramatically, proving the validity of SSODS.

This paper presents an approach to investigate the influence of metamaterial to radio-frequency (RF) magnetic field in magnetic resonance imaging (MRI) at 3T. The variety of magnetic fields of RF receiving coil was calculated using the commercial electromagnetic simulation software (CST). The simulation results demonstrate that the transmitting and receiving magnetic field (B1+ and B1-) can be enhanced when the metamaterial is inserted into the RF coil, suggesting that the metamaterial has potential in MRI applications at 3T.

Recently, a new oscillation phenomenon—intermittent subsynchronous oscillation (ISSO)—has been observed in a large interconnected power grid. Rather than leading to oscillatory instability, ISSO causes cumulative fatigue damage and reduces the shaft life of the generator. The existing phase-compensation-based damping technologies are found to be limited in mitigating these types of oscillations. To mitigate ISSO, a subsynchronous modulation of reactive current (SMRC) approach is established and implemented in the voltage-source converters (VSCs) at the generator terminals. The contribution of SMRC to system damping has been analyzed in order to select control parameters for the VSC. The SMRC controller has been prototyped and extensively tested on a real-time closed-loop simulation platform equipped with a newly developed speed sensor module for precisely interfacing the real-time digital simulator with the rotating speed-acquisition board. Extensive experiments on the input and output characteristics of the VSC have been carried out to test and validate the damping current generating module. The effective damping areas are obtained from test observations to fine tune the parameters of the VSC controller for adapting to various system operating conditions, resulting in the common optimal damping region. Real-time simulations, onsite commissioning, and statistics have demonstrated the ability of the SMRC to mitigate ISSO and subsynchronous oscillation in power plants.

High noise and strong volatility are the typical characteristics of financial time series. Combined with pseudo-randomness, nonsteady and self-similarity exhibiting in different time scales, it is a challenging issue for the pattern analysis of financial time series. Different from the existing works, in this paper, financial time series are converted into granular complex networks, based on which the structure and dynamics of network models are revealed. By using variable-length division, an extended polar fuzzy information granule (FIGs) method is used to construct granular complex networks from financial time series. Considering the temporal characteristics of sequential data, static networks and temporal networks are studied, respectively. As to the static network model, some features of topological structures of granular complex networks, such as distribution, clustering and betweenness centrality are discussed. Besides, by using the Markov chain model, the transfer processes among different granules are investigated, where the fluctuation pattern of data in the coming step can be evaluated from the transfer probability of two consecutive granules. Shanghai composite index and foreign exchange data as two examples in real life are applied to carry out the related discussion.

For high speed ultra-wideband (UWB) communication systems, the multipath interference exhibits a primary obstacle to improve transmission performance. In order to enhance the signal to interference plus noise ratio (SINR) in the receiver, a partial template receiver is proposed in this paper. Instead of using the conventional template, the model in this paper adopts a partial template to demodulate signals. To analyze the performance of the proposed receiver, bit error rate (BER) formulation of IR-UWB systems in the presence of multipath interference, multiuser interference and addictive white Gaussian noise (AWGN) is derived in IEEE 802.15.4a channel models. Simulation results show that, compared with the conventional correlation receiver, the proposed receiver can achieve a better BER performance for high Eb/N0, which falls in the conventional used Eb/N0 range., 4 pages, 5 figures, Communications and Networking in China (CHINACOM), 2011 6th International ICST Conference on

This paper proposes a novel day-ahead dynamic economic dispatch model for the wind integrated power system, aiming to minimize the total cost of generation and reserve capacity of all units. The proposed model is formulated as a chance-constrained stochastic nonlinear programming (CSNLP) problem, in which the constraints of regulating characteristics of units are taken into account. A two-stage iterative algorithm, based on sequential quadratic programming (SQP) method and chance-constraint checking, is developed to solve the CSNLP efficiently. Finally, the proposed dispatch strategy is illustrated in an IEEE30 power system with six generators and a wind farm.

The capability to damp sub-synchronous oscillations of single-phase TCSC, two-phase TCSC, three-phase TCSC is comparatively studied in this paper. SVR (Synchronous Voltage Reversal) is used as the control strategy of these three schemes. And IEEE first benchmark model is taken as the simulation example. Generator power, torques and LVUR (Line Voltage Unbalanced Voltage) are simulated. The results show that all the three schemes can effectively suppress SSO, but compared with single-phase and three-phase TCSC, the convergence rate of generator torques in the two-phase TCSC scheme is slower, thus its damping effect is worse, while single-phase and three-phase nearly has equal damping capacity. After the three-phase fault, the steady value of LVUR under three schemes can all meet the requirements of national standard in China. Through the comparison between these three schemes, it can be concluded that single-phase TCSC is a new structure which has great potential to apply to practical projects, but further theoretical analysis and much more simulation should be done to verify.

The methods for subsynchronous oscillation mitigation based on SVC and STATCOM are analyzed in this paper. According to the IEEE first benchmark model, the electrical damping coefficients respectively provided by SVC and STATCOM connected at the generator terminal, as well as positive damping condition, are deduced by complex torque coefficient approach. Correlative factors which influence the two positive dampings are compared. The analysis results indicate that the positive damping provided by SVC is proportional to the size of system voltage. The positive damping provided by STATCOM is not affected by the size of system voltage, which is mostly proportional to the subsynchronous voltage produced itself. The controllers of SVC and STATCOM are designed and the positive dampings separately offered by SVC and STATCOM are optimized by phase compensation with test signal method. The time domain simulation reveals that STATCOM has stronger damping ability than SVC in the case of short circuit fault.

Subsynchronous oscillation (SSO) with low amplitude that exceeds cumulative fatigue threshold of the generator shaft frequently could significantly reduce the shaft’s service life, which is a new SSO problem that emerges in recent years. According to the real recording oscillograph, the basic reason for frequently over-threshold SSO with low amplitude at multi-power plants was analyzed based on Hulunbuir League system. The sensitivities of the electrical damping to the main electrical parameters in the contributing loop of subsynchronous torsional interaction were calculated. Based on the sensitivities, a simulation method was presented, which was used to excite the same oscillation as the actual case by exerting disturbance on the firing angle. The limitation of wide-band and narrow-band supplementary subsynchronous damping controller (SSDC) for mitigating this kind of SSO was analyzed based on the electromagnetic transient simulation model of Hulunbuir League system. The difference of supplementary excitation damping controller (SEDC) and parallel-form FACTS connected to the generator terminal was compared from the aspects of response time and the ability of damping torque supplying. The analysis indicates that their response time is similar but FACTS has stronger ability of damping torque supplying than SEDC. Time-domain simulation method was used to compare the mitigation effects of SEDC, static var compensator (SVC) and static synchronous compensator (STATCOM). Considering the mitigation effect, the floor space limit of the power plant and so on, STATCOM was considered as the best mitigation measure. A control strategy of cascaded STATCOM for engineering application was presented and the capacity for SSO mitigation as well as output characteristics was analyzed. The analysis indicates that STATCOM using the proposed control strategy has better mitigation effect and output characteristics with smaller capacity.

Background: It has been demonstrated that hypertrophic scar fibroblasts (HSFs) overexpress collagen messenger ribonucleic acid (mRNA) and protein, especially α1 collagen. Antisense nucleic acids are effective in inhibiting harmful or uncontrolled gene expression, suggesting that antisense ribonucleic acid (RNA) can effectively downregulate the expression of α1 collagen gene and attenuate the scars. Aims: This study was conducted to observe the effect of recombinant plasmid pREP9-COL1 on α1 collagen expression in HSFs and clarify the prospect of antisense RNA on scar treatment. Methods: The α1 collagen gene fragment including the region of 5′ UTR to exon (229 bp) was cloned in the eukaryotic expression plasmid pREP9 in the antisense orientation relative to the RSV-LTR promoter to reconstruct the pREP9- COL1 plasmid. Then it was transferred into HSFs through lipofectamine. The expression of α1 collagen was examined by immunostaining, reverse-transcriptase polymerase chain reaction, and Western blots. Results: The recombinant plasmid pREP9-COL1 with a correct sequence was constructed successfully; pREP9-COL1 consistently inhibited human α1 collagen gene expression at both mRNA and protein levels. Conclusions: Antisense RNA was effective in downregulating α1 collagen expression of HSFs. Therefore, this approach offered a prospect of scar treatment by attenuation of α1 collagen production with antisense RNA.

According to the phase space reconstruction techniques from one-dimensional time series and the quantitative criteria of chaotic system, analyses and computations are conducted on Electroencephalogram (EEG) signals of piglets resulted from HAI (hypoxic–asphyxic injury) experiments. Based on the comparative studies of the phase graph, the power spectra, the correlation dimension, and the Lyapunov exponent of EEG signals of piglets, under normal and injury conditions, the following conclusions are shown: (1) the analyses of phase graph, power spectra, correlation dimension and Lyapunov exponent of EEG signals manifest the whole dynamic characteristics of cerebrum, and they may be used as new quantitative methods for early diagnosis of brain injuries. (2) Under normal physiological conditions, EEG signals are chaotic; while under pathologic conditions, EEG signals approach regularity.

The physical model of this paper is an irregular enclosure with double flexible plates. The primary source is the vibration of Plate A excited by a point force. The secondary source is the vibration of Plate B excited by a polyvinylidene fluoride (PVDF) actuator. First, the interaction of the PVDF actuator and a thin plate is analyzed and the distribution of strain and stress is gained. Based on the hypothesis of linear distribution of strain on two sections of the plate–film system, a formula is deduced to calculate the rate of the strain distribution. Then an experiment is proposed to test the sound pressure response in an irregular enclosure under the excitation of the PVDF actuator. Second, the theoretical formulas of the mode contributions of the two plates and the cavity are deduced. Then the formulas are converted into compact matrix equations. Thus the expression of sound response of one point in the enclosure is gained under the excitation of both the primary and the secondary sources. Based on these results, the sound pressure square is taken as the control aim function. At last the optimized curves of control voltage and control phase are achieved.

In Inner Mongolia of China, the generators in several power plants are experiencing a new subsynchronous interaction problem. It belongs to subsynchronous torsional interaction (SSTI) between the generators and HVDC, but has many different characteristics from conventional SSTI. This paper describes the different characteristics according to the actual recording. Preliminary analysis is made for the root cause as well as the probable disturbance source. PSCAD/EMTDC is used to build up equivalent model of the power system and complex torque coefficient approach is utilized to scan the electrical damping characteristics of the system. A stimulation method is presented to simulate the similar disturbance as actual condition. The feasibilities of several mitigation countermeasures are analysed in detail and finally the countermeasure that STATCOM at the generator terminal is recommended.

How to develop students' capacity for computational thinking during the teaching process of computer programming, is one of the basic goals of computer fundamental education. Using C program language as example, this paper discusses how to train thinking capability of students during the programming language teaching. Computer programming languages have the features of mass content and practical techniques, and it is difficult for students to master one in short period of time. We provide some advices about how to organize the teaching content and experiments are proposed for improving the teaching results, and human thinking characters are exploited for increasing creative capability. The teaching methods proposed have proved effective for training thinking capability of students.

The 3DTown project is focused on the development of a distributed system for sensing, interpreting and visualizing the real-time dynamics of urban life within the 3D context of a city. At the heart of this technology lies a core of algorithms that automatically integrate 3D urban models with data from pan/tilt video cameras, environmental sensors and other real-time information sources. A key challenge is the "three-dimensionalization" of pedestrians and vehicles tracked in 2D camera video, which requires automatic real-time computation of camera pose relative to the 3D urban environment. In this paper we report preliminary results from a prototype system we call 3DTown, which is composed of discrete modules connected through pre-determined communication protocols. Currently, these modules consist of: 1) A 3D modeling module that allows for the efficient reconstruction of building models and integration with indoor architectural plans, 2) A GeoWeb server that indexes a 3D urban database to render perspective views of both outdoor and indoor environments from any requested vantage, 3) Sensor modules that receive and distribute real-time data, 4) Tracking modules that detect and track pedestrians and vehicles in urban spaces and access highways, 5) Camera pose modules that automatically estimate camera pose relative to the urban environment, 6) Three-dimensionalization modules that receive information from the GeoWeb server, tracking and camera pose modules in order to back-project image tracks to geolocate pedestrians and vehicles within the 3D model, 7) An animation module that represents geo-located dynamic agents as sprites, and 8) A web-based visualization module that allows a user to explore the resulting dynamic 3D visualization in a number of interesting ways. To demonstrate our system we have used a blend of automatic and semi-automatic methods to construct a rich and accurate 3D model of a university campus, including both outdoor and indoor detail. The demonstration allows web-based 3D visualization of recorded patterns of pedestrian and vehicle traffic on streets and highways, estimations of vehicle speed, and real-time (live) visualization of pedestrian traffic and temperature data at a particular test site. Having demonstrated the system for hundreds of people, we report our informal observations on the user reaction, potential application areas and on the main challenges that must be addressed to bring the system closer to deployment.

In this work the goal is to develop a distributed system for sensing, interpreting and visualizing the real-time dynamics of urban life within the 3D context of a city focusing on typical, useful dynamic information such as walking pedestrians and moving vehicles captured by pan-tilt-zoom (PTZ) video cameras. Three-dimensionalization of the data extracted from video cameras is achieved by an algorithm that uses the Manhattan structure of the urban scene to automatically estimate the camera pose. Thus, if the pose of the video camera changes, our system will automatically update the corresponding projection matrix to maintain accurate geo-location of the scene dynamics.

Bit error rate (BER) performance of impulse radio Ultra-Wideband (UWB) systems in the presence of intrasymbol interference, inter-symbol interference, multiuser interference and addictive white Gaussian noise (AWGN) is presented in this paper. By analyzing the indoor office LOS channel model defined by IEEE 802.15.4a Task Group and deducing the variance for intra-symbol interference (IASI), inter-symbol interference (ISI) and multiuser interference (MUI), the system BER expression is obtained and verified by MATLAB simulations. Through comparing the simulation results with and without intra-symbol interference, the conclusion that intra-symbol interference cannot be neglected is drawn-moreover, such interference will significantly decrease performance of UWB based wireless sensor networks (WSN). Then, the BER performance of UWB systems in multiuser environment is also analyzed and analysis results show that multiuser interference will further worsen the transmission performance of UWB systems., Comment: 5 pages, 2 figures, Communications and Networking in China (CHINACOM), 2011 6th International ICST Conference on

During the process of establishing the capacitivmicro-accelerometer PSPICE Simulation Model, consider in the precise electrical model of the capacitance, According tthe characteristics of MEMS capacitance, established micraccelerometer PSPICE simulation model. In the model, thelectrical and mechanical coupling process of Capacitiv MEMS sensor was analyzed. By using this simulation mode the closed-loop detection circuit was simulated by PSPICE The simulation results show that the closed-loop capacitanc detection circuit can effectively improve the linearity and thmeasure range of the capacitive micro-accelerometer, it caeliminate mechanical resonance. But the closed-loop system' stability and response speed must be ensured. Therefore, the stablishment of capacitive micro-accelerometer PSPIC simulation model is very valuable to the design and simulatio of the closed-loop capacitive detection circuit.

Traditionally, for a cotton spinning corporation, its quality data acquisition, analysis, and monitoring were separated. In order to improve the quality management of the enterprise, this paper completes and depicts the framework construction of integrative system of quality data acquisition, analysis, and monitoring oriented to the cotton spinning corporations. It also elaborates the technology of quality data acquisition, analysis, and monitoring in the process of production management of this enterprise. The executive results shows that this system has enhanced the quality awareness, significantly increased the products quality, and reinforced the core competitiveness of the enterprise.

AODV is an on-demand routing protocol for mobile ad hoc network, with advantages of low load of control, low power consumption as well as low-bandwidth overhead. The routing table in AODV, however, maintains only one route to the specified node. Therefore, the source node needs to re-initiate route discovery process as a route fails. To solve this problem, an improved method is presented in this paper. The proposed scheme suggests that each source node maintains an alternative route to the specified destination node. When the primary route fails, the source node will use the backup route to send packets. Simulation results show that this modification can not only improve the packet delivery fraction but also reduce the average end to end delay, the routing overhead and the route discovery frequency.

RFID technology is considered as one of the most influential information technologies, since the transmission between reader and other equipments is completely opened through wireless channel, this has potential risks. This paper analyzes RFID system's hidden danger, designs an RFID authentication protocol based on shared key and proves its advantages compared with the other protocols. In order to reducing the calculation burden of tag and reader, this protocol gives full play to the role of RFID middleware and database ,and makes effort to achieve system's security ultimately.

Dendritic cell(DC) is a kind of natural immunocyte, and also is a kind of typical antigen presenting cell, which can stimulate and inhibit immune system. The function of the dendritic cell in the human body can be abstractly extracted as an dendritic cell algorithm(DCA). In this paper we try to extract a new immune algorithm based on the dendritic cell. Through the simulation experiment, an new anomaly detection based on DCA shows more advantages, compared with the conventional anomaly detections.

E-business is an advanced commerce pattern, which is centered on electronic trade, and takes actualizing buddy benefit and information share together such as customers, suppliers, sellers, and logistic distribution enterprises as the target. The integrated e-business is an advanced e-business, which is based upon collaboration and effective approaches to solve the problems in the enterprise such as ldquoinformation islandrdquo and ldquoresource islandrdquo. CPC is a kind of advanced business management idea and a kind of advanced commerce solution based on the Web, which conforms to the requirement of the mass customization. It locates customers and services at the center, and realizes cooperation and intercommunication between the related people in the whole lifecycle. According to the actual development of the CPC theory and the domestic e-business, the integrated e-business and some relative problems based on CPC are researched in this paper. The workflow and the system framework of the integrated e-business system based on CPC are proposed. Finally, the characteristics of the integrated e-business system based on CPC are summarized briefly.

Semi-insulating GaAs substrates doped with chromium were implanted with 120-160 ke V28Si+ ions (1012-1013 cm-2 at room temperature. After thermal annealing, the carrier concentration and mobility profiles, residual damage and impurity levels of implanted wafer were determined by C-V method, back scattering technique and photo-1uminescence spectra. The results showed that the semi-insulating GaAs substrate selection and 28Si+ beam purity control are necessary to obtain reproducible and high activation implantation. Fabricated with multiple localized silicon implantation for both active and contact layer, GaAs dual-gate MES FET applicated in UHF TV tuner reached a noise figure of 0.9 dB and an associated gain of 10 dB at 1 GHz. The mobility profile and appropriate annealing temperature are discussed on the basis of the present experimental results.