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In social media, useful data information is mined to identify hot topics and predict the development direction of hot topics. The research method is to use web crawler to obtain relevant data, find new hot topics in media, get the original data, use Jieba to segment words, generate word segmentation results, obtain eigenvalues through Term Frequency - Inverse Document Frequency (TF-IDF) word frequency statistics, and use k-means algorithm to complete the clustering of eigenvalues, obtain the cluster results, and judge the hot topics in the cluster. In the experiment of advanced optimization hot topic, Linear Discriminant Analysis (LDA) method is used to classify the topic model, Gibbs sampling is used to sample and train the model, and K-means algorithm is used to achieve the purpose of clustering. The recall rate, accuracy rate and F value are calculated, and the experimental results of hot topics are summarized and analyzed to obtain the LDA model results of current hot topics in network media.

In this paper, a low-cost SDR hardware platform is proposed. The hardware platform can carry out experiments using amplitude-comparison method, phase Interferometer, time difference of arrival and hybrid direction finding and locating techniques. By integrating with artificial intelligence algorithm of amplitude-comparison method is designed and is also implemented to complement the hardware platform. The outfield test show that accuracy of detecting UAV is about 10 degree with hardware platform with amplitude-comparison method.

In view of the complexity and low accuracy of existing fault diagnosis methods for transmission network, this paper proposes a novel transmission network fault diagnosis method combining simplified Bayesian network and fault decision table. First, using the information from Supervisory Control and Data Acquisition (SCADA) system, there develop a fault area identification method, which utilizes circuit breaker (CB) information to isolate the components to build a fault area. In fault area, there creates the simplified Bayesian network to associate components with CBs. Further, the paper proposes a calculation method to calculate the fault probability of components in fault area, which is able to determine the suspicious component set. According to the sequence of relay actions, a fault decision table for the suspicious component set can be established. Finally, the fault condition of components, CBs and protection devices are diagnosed by comparing the local fault decision table. The above method greatly simplifies the complexity of Bayesian network, and the test results show that the speed and accuracy of its fault diagnosis have been significantly improved.

The failure of the fiber channel of the measurement and protection device of power system may lead to protection failure and system out of control. This greatly affects the safety and reliability of system operating. First, this paper discusses the fiber communication method and its channel fault diagnosis method of fiber pilot protection devices, and designs an online monitoring method that cooperates with the physical links and communication status of those devices. Second, using uncertainty communication fingerprint detection technology, it can diagnose some uncertain issues of protection information mis-transmitted, protection device refusing to move and mis-operation. Finally, taking a certain transmission line protection system equipped with optical fiber communication as test case, the experimental results verify that the proposed diagnosis method has good effectiveness and accuracy in diagnosing fiber channel faults. Keywords—fiber pilot protection, protection device failure, fiber channel fault location, communication fingerprint

The setting of traditional distance zone-II protection is very complicated, which is due to the difficulty in determining the operating mode and its branch coefficient under the cooperation of multiple lines. So this paper proposes a novel simplified setting method of distance backup protection. This method simplifies the calculation of setting value and accelerates the action time of protection device, which makes the distance zone-II protection only cooperate with the protection of zone-I of local line and only consider the sensitivity coefficient. To further ensure the selectivity of relay protection, the paper develops a fault line detection to match the above method based on random matrix spectral analysis, whose matrix formed by the measured lines current. Then the paper designs a feasible simplified setting process of distance zone-II backup protection by integrating the above methods. Finally, the example analysis shows the simplified setting method of distance backup protection can ensure the selectivity of relay protection, correctly identify the faulty line and speed up the action time.

This paper presents an ultra-low power digitally-assisted analog ring phase-locked loop (PLL) with a tunable switched capacitor loop filter. The PLL achieves a power efficiency of 0.213mW/GHz and FoM of -234.4dB at. 08V supply with only 200ns lock time at 100MHz reference clock. All the components are using a single supply voltage and it can operate from 0.5V to 0.9V supply with a wide output clock frequency range from 0.2GHz to 5GHz. At 0.5V supply, it can support 1.6GHz operation with very high power efficiency of 0.08m W/GHz. It can also support a wide reference clock frequency range from 20MHz to 200MHz. This low power design is suitable for System-on-Chip (SoC) and Internet-of- Things (IoT) processors.

As the push for low-power, low-jitter, and low-area phase-locked loop (PLL) design [1] continues in the 10nm node and beyond, the leakage from various sources could become an issue in the applications where the reference clock frequency is low and the static phase error is required to be close to zero at all process corners and temperatures. The impacts of leakage currents on analog PLLs are the increase of static phase error, higher jitter and reference spur. To mitigate the leakage sensitivity in analog PLL designs, digital PLLs have been designed [2–3], but they often exhibit higher power consumption and higher jitter due to quantization noise, and require high-performance voltage regulators or supply-noise cancellation techniques [4] due to their high sensitivity to power-supply noise. To compensate for the leakage current in analog PLLs, analog compensation circuits are proposed [5–6], but it is impossible to achieve zero or low phase error across PVT corners.

Regarding the robustness and dynamic response issue of unstable second order process with time delay (USOPTD), a new re-optimized design strategy based on twice-optimal control (TOC) theory is proposed. First, on the basis of the TOC, the system infinite dimensional controller and state observer are constructed, which is verified to eliminate the impact of time delay on the system, so it has strong robustness. Second, a local feedback K F value is increased to eliminate the oscillation during the transition process of TOC system. Then, in order to improve the rapidity of the system, a square-root amplifier (SRA) has been applied to the re-optimized designing system. Finally, simulation-based comparisons of this method and the other regular control approaches have been made. The results show that the new system has not only a fast and more smoothly tracking responses but also strong robustness to load disturbance and parameter perturbation. Moreover, the new method is simple, practical and easy to tune parameters, thus providing guidelines for industrial applications of similar systems.

The dispatching of labor and distribution of tasks among workers are important aspects of corporate operations. Labor dispatch refers to the dispatching of employees to meet with clients; however, dispatches commonly vary with time. This means that any analysis pertaining to labor dispatch and work distribution should also vary with time. In this study, MATLAB was used to analyze data from anonymous caseworkers in central Taiwan in order to identify relationships between the location of their offices and the homes of their clients. Our aim was to determine the rationality behind labor dispatch and work distribution. This led us to develop a novel method by which to dispatch labor in order to achieve a more equitable distribution of work. Simulations demonstrate the efficacy of the proposed scheme in improving labor dispatch and work distribution.

In the network environment with limited network resources, the overall bandwidth is usually competitively shared among various application users. The traffic engineering techniques presented for resolving the bandwidth sharing, e.g. limited traffic rate and traffic blocking, may not be able to satisfy the requirement for all types of services. In this paper, we propose an effective routing mechanism for link congestion avoidance in the software-defined networking (SDN) environment. We use a SDN controller to handle actions and forwarding rules. The bandwidth is dynamically allocated to deal with link congestion using a centralized control mechanism. According to the bandwidth utilization, we redirect the traffic from congested links to enhance the efficiency of link usage. In the experiments of emulating congested traffic, we are capable of getting better network performance of throughput, jitter, and packet loss rate using the proposed traffic rerouting, as opposed to the environment without traffic rerouting.

In this paper, a high gain receiver front-end is proposed. The full-wave analysis method is used to simulate the PCB with box. Combined with electromagnetic field simulation, the front-end circuit electrical specifications are analyzed by ADS. According to the simulation, the receiver front-end is fabricated and tested. The test results are agreed with the simulation. The working bandwidth is about 22MHz. the frontend test gain is more than 80dB, and system noise figure is about 3dB.

This paper proposes a high performance frequency synthesizer system featured by ultra-broadband, low phase noise. In order to achieve frequency synthesizer covering 0.4∼18GHz with 10MHz step, two PLL (Phase Locked Loop), mixer, microwave switch, multiplier, frequency divider, and band-pass filter are been used. The three-section frequency VCO is use to generate 4.5∼9GHz frequency signal. The 0.4∼0.45GHz frequency signal is obtained by division of 4.5∼9GHz frequency signal, and the 9∼18GHz signal is obtained by frequency doubler of 4.5∼9GHz frequency signal. The frequency synthesizer's output power level is −50dBm∼0dBm, the phase noise is better than −85dBc/Hz@1KHz, and the suppression to spurious is better than −55dBc.

The transmission properties of the light through the glass convex lens can be analyzed by classical theory. In quasi-optical technology, the Gaussian beam transmitting through the dielectric convex lens can be analyzed by the paraxial theory. The lens can convert a divergent Gaussian beam into convergent and the beam waist radius of the output beam can be determined by the incident beam and the focal distance of the lens. In this paper, the transmission properties of the zero-order Bessel beam through the dielectric convex lens are discussed. Some simulated results are given.

In millimeter wave and THz band, the wave always propagates in the form of beams, such as Gaussian beam, Bessel beam. The generation, control, and transform of these beams are very important. This paper proposed a reflectarray to transform these beams at millimeter wave length. By properly design the reflect phase shift at each position on the reflectarray, a quasi-Gaussian beam is transformed into Gaussian beam and a Gaussian beam is transformed into zero-order Bessel beam. The simulated results show that the beam transformation efficiency of the reflectarray is approaching the transparent transformation technology.

With the rapid development of modern communication technology, the communication network environment becomes more and more complex. Aiming to meet the requirement of identifying the wireless signal, which is located in the same frequency band of WCDMA defining as an intelligent monitoring method based on spectral correlation has been identified effectively. Firstly, the power spectrum of the frequency band is used for the identification of the initial alignment, then spectrum correlation method is used to extract the feature of the strong anti-interference. By analyzing and extracting characteristics of the received signal, our method presents an efficient monitoring framework which is robust to identify the WCDMA signal. The experimental results show that these features can maintain a certain stability when low SNR and multipath channel change. Experimental results validate the reliability and validity of our method.

With the rapid development of modern communication technology, communication networks become increasingly complex environment. In order to monitor if the wireless signal with the same frequency is illegal, this paper proposes a method of intelligent recognition to CDMA2000 based on spectral correlation. First, the power spectrum is used for initial comparison, then, we use spectral correlation to extract the characteristics of strong anti-jamming capability, cross correlation coefficient γ1 between the sections of cycle frequency and frequency, cross correlation coefficient m between the sections of cycle frequency and projection of cyclic spectrum on the surface of the frequency α = m / T, cross correlation coefficient Rxα(τ) between the sections of frequency and projection of cyclic spectrum on the surface of the frequency α, so as to compare features. The experimental results show that these features can maintain a certain stability when low SNR and multipath channel change, and can effectively identify whether the signal is CDMA2000. Therefore requirements of CDMA2000 signal intelligent recognition is satisfied.

In this paper, we generate the zero-order Bessel beam at W band using a diagonal horn, a convex lens, and an axicon. The generated Bessel beam has smaller beam spot size than the Gaussian beam. Some imaging experiments with the generated zero-order Bessel beam are done. The results show that the millimeter wave imaging with the zero-order Bessel beam can get an imaging resolution of about 1mm to 2mm.

This paper reports the first on-chip demonstration of GHz range real time spectrum analysis (RTSA) using an integrated dispersive delay line (IDDL). The IDDL is implemented in a standard 0.13 μm CMOS process and can operate from 0.4 GHz to 4 GHz with 1.2 ns dispersion. The IDDL provides a frequency-to-time mapping which can be utilized to generate a time domain representation of the frequency components. We demonstrate that the IDDL is capable of real time spectrum analysis of signals within the frequency range of 0.4 GHz to 4 GHz.

Control a closed-circuit grinding process is a challenging problem due to its complex dynamic characteristics and heavy interactions among the control loops. Especially the various process disturbances and uncertain dynamics have a great influence on the control performances of the closed-loop system. In this paper, a compound control strategy by combining the analytical decoupling control and disturbance observer (DOB) technique is proposed to handle such an intricate multivariable process. The decoupling controller acts as prefiter and is used to generate appropriate control actions such that a desired setpoint tracking response is achieved. The DOB is employed to estimate the various disturbances and suppress them by feedforward compensation design. Control studies have been performed by simulation tests for setpoint tracking and disturbance rejection problems.

In this paper, we report an on-chip implementation of a Ku-band nanosecond scale time-stretching (TS) system in a 130 nm CMOS process. The system employs a linear chirp generator realized by ramping the control voltage of the voltage controlled oscillator (VCO), a broadband amplitude modulation (AM) circuit and an active dispersive delay line (DDL) improved from a previous integrated DDL, showing 1 ns dispersion over the frequency range from 12 GHz to 16 GHz. This work not only shows the experimental demonstration of the time stretching effect on the pulsed signal, but also indicates the potential for implementation of more complicated time scaling signal processing systems on chip.

In view of the blocking problem existing in automatic production line for certain large H-shaped steel at the stage of production, the paper will analyze the cause and put forward optimization method for the motion of stratifying machine. Under the circumstance of no increase of equipment hardware, technical transformation (soft reconstruction) will be made only for the flow procedure of S7–400PLC, which will not only improve the working efficiency, but also resolve the problem of steel blocking thoroughly.

There are multiple theoretically appropriate revolving speeds for grinding mill barrel of cement plant, but to choose which revolving speed is more reasonable shall be adjusted in accordance with various type of cement mill. The discussed object in this paper is a 4> 1.83m × 6.4m cement mill. In the study, records are made for statistics on the course from the beginning of lessening feeding amount, and gradually increasing feeding amount to slightly exceed the output. The comparison was made between before the consumption and after the consumption by slightly accelerating the revolving speed and exceeding the output, and the profits were achieved to some extent, which proves the method is feasible.

International audience; Segmentation and tracking of tagged MR images is a critical component of in vivo understanding for the heart dynamics. In this paper, we propose a novel approach which uses multi-dimensional features and casts the left ventricle (LV) extraction problem as a maximum posteriori estimation process in both the feature and the shape spaces. Exact integration of multi-dimensional boundary and regional statistics is achieved through a global formulation. Prior is enforced through a point-distribution model, where distances between landmark positions are learned and enforced during the segmentation process. The use of divergence theorem leads to an elegant pairwise formulation where image support and prior knowledge are jointly encoded within a pairwise MRF and the segmentation is achieved efficiently by employing MRF inference algorithms. Promising results on numerous examples demonstrate the potentials of our method.

A fully-overlapped multi-mode QC-LDPC decoder architecture, adopting improved TDMP algorithm, is presented in this paper. With symmetrical four-stage pipelining, block column and row permutations, nonzero sub-matrix reordering, sum memory odd-even partition, and read-write bypass, two phases are fully overlapped and each phase scans nonzero sub-matrices one by one in block row-wise order without access conflicts to sum memories. The sum memories store not only variable node sums but also prior messages. In this case, it saves an additional FIFO of 13 440 bits. The decoder attains 248-287 Mb/s at 150 MHz and 15 iterations.

This paper presents a dual-path fully-overlapped QC-LDPC decoder for the WiMAX system. Each phase scans nonzero sub-matrices two by two in block row-wise order, and two phases are fully overlapped. It reduces memory accesses by 24.3–48.8%, and takes only 48–54 clock cycles per iteration. It is fabricated in SMIC 0.13 µm 1P8M CMOS process, which occupies 4.84 mm2, attains 847–955 Mb/s, and consumes 397 mW with power efficiency of 42 pJ per bit per iteration.

In this paper a programmable and area-efficient decoder architecture supporting two main stream decoding algorithms for any Block-LDPC codes is presented. The novel decoder can be configured to decode in either TPMP or TDMP decoding mode according to different Block-LDPC codes. To verify our proposed architecture, a flexible LDPC decoder which supports IEEE 802.16e is implemented using a 0.13um CMOS process with a total area of 6.3 mm2 and maximum clock frequency of 260 MHz. The estimated comsumption is 270 mW when operates at 125 MHz and 1.2V supply.

This paper presents a high efficiency feedforward power amplifier with Doherty technique for multi-carrier GSM base-station. The main Doherty power amplifier (DPA) was designed with third-order intermodulation distortion (IMD3) cancellation technique and tunable power division for optimized linearity and efficiency. The error amplifier was selected based on IMD3 analysis for higher efficiency. Two tone test show the amplifier has an efficiency of 27.2% and an IMD3 below −62.5dBc at 80W overall output power, the efficiency is much higher than traditional feedforward amplifiers.

Based on the Min-Sum algorithm, this paper proposes an LDPC decoder integrating the TDMP schedule, which could achieve low complexity as well as good performance. The LDPC decoder is for DVB-S2, which includes 11 kinds of code rates with a block size of 64800. Based on SMIC 0.13µm standard CMOS process, the LDPC decoder has an estimation area of 14mm2, a throughput of 135Mbps with a frequency of 105MHz and maximum iteration number of 30,which shows advantage over previous DVB-S2 LDPC decoders1.

Since Low-Density Parity-Check codes have near-capacity decoding performance and very high decoding throughput, they have been employed as FEC coding scheme in many transmission standards for wireless communication, such as IEEE 802.22n, IEEE 802.16e, DVB-S2, and DTMB. This trend triggers the need for so-called multi-standard LDPC decoders. In this paper, a flexible architecture that supports multiple code rates, variable block sizes and is code independent for block-LDPC codes is proposed, based on rearranged TPMP algorithm,. By implementing a dynamically reconfigurable RPPU, our proposed architecture can be configured into row update or column update mode by time-division multiplexing. Consequently, the decoder achieves a high area and power efficiency. To verify our proposed architecture, a novel LDPC decoder which supports IEEE802.16e standard has been implemented. The results on a 0.18 um CMOS process show that the decoder occupies an area of approximately 13.7 mm2 and runs correctly at an maximum operating frequency of 110 MHz, resulting in 98 Mbps decoding throughput1.

For the complex development process of media broadcasting demodulator chip, it is proposed that a low cost, high reliability verification and test scheme at system level in this paper. This scheme emphasizes the collaboration of algorithm simulation, RTL description, FPGA verification, ASIC realization and any other stages of chip development. All these stages constitute an organic, closely interconnected whole. And for the particularity of communication chip, this scheme can solve function verification and performance test, ensure the accuracy, completeness and reliability of the test and verification. Then both the development time and the cost of the product are significantly reduced. This verification and test scheme has been applied to the demodulation chip of the receiver of Chinese broadcasting standard DTMB system.

In this paper, the design and experimental results of a multi-beam antenna for communications link are presented. The proposed antenna has 16 circular waveguide ports around a constant permittivity dielectric spherical lens. By controlling the feeding network of the waveguide, the radiation pattern of the antenna can switch from one beam to another. The gain of each beam of the designed multi-beam antenna is about 28dB, the sidelobe levels of all the 16 beams are lower than −15dB, and the adjacent beam overlap is about at −5dB. The measured radiation performances of the multi-beam antenna have good agreements with the simulations.

Triethylenetetramine(TETA) was reacted with carbon bisulfide in an alkaline medium in order to prepare a bisdithiocarbamate chelator, namely sodion triethylenetetramine- bisdithiocarbamate(DTC-TETA). The chelator was characterized and examined by FTIR, UV spectroscopy and elemental analysis. Its complexes with heavy metal ions were also checked by UV spectroscopy. Comparison of heavy metal ions' stability for DTC- TETA with that for sodium diethyldithiocarbamate (DDTC) was accomplished using flame atomic absorption spectrometry (FAAS) coupled with flow-injection. By introducing NCS groups onto the TETA terminals, the FTIR spectrum shows strong absorption peaks at 1461~1388 cm -1 and 1174 ~ 996 cm -1 which were attributed to partly double bonds of C - .... N and C - .... S, respectively, representing the formation of DTC-TETA. The UV spectrum of DTC-TETA has two absorption peaks at 265 nm and 290 nm, assigned to pi-pi* transition of NhellipChellipS radical and nonbonding electron n-pi* transition of ShellipChellipS radical to conjugated system, respectively. The elemental analysis results demonstrate that the mol ratio of C, H, N and S in DTC-TETA was about 2:4:1:1. As for UV spectra of its Complexes with Cu (II) , Cd (II) , Zn (II) and Ni (II) , there are new four absorption peaks at 321 nm, 310 nm, 311 nm and 325 nm, respectively, confirming the formation of metal complexes. Coupled with flow- injection, FAAS determination shows that the complexation properties ofCu 2+ , Cd 2+ , Ni 2+ and Zn 2+ complexes of DTC-TETA are all better than those of DDTC at the same concentration.

Thermal power plants dominate electric power generation in Taiwan, which are also the major contributor to Green House gases (GHG). CO2 is the most important greenhouse gas that cause global warming and sea-level rising. This paper pierces the relationship between GHG reduction and power generation expansion planning (GEP) problem for the utility. Refined Immune Algorithm (RIA) is presented to determine the generation expansion planning strategy of the utility with independent power providers (IPPs). The utility has to take both the IPPs' participation and environment impact into account when a new generation unit is expanded. This problem also takes into account the GHG reduction and reliability issues, while satisfying all electrical constraints simultaneously from view of supply side. RIA was conducted by an improved crossover and mutation mechanism with a competition and auto-adjust scheme to avoid prematurity. Testing results shows that RIA can offer an efficient way in determining the generation expansion planning.

Recently the concern about network security has been increasing rapidly, certain malicious programs like Trojan horses are highly hazardous to the Internet security. In this paper, we firstly discuss the current research and developing trend to anti-Trojan approach on behavioral analysis. Moreover the behavioral features of Trojan at the stage of installation will be analyzed and summarized. Further we propose an anti-Trojan approach in Windows platform, which can interpret and remove Trojans effectively at the stage of installation. By using this method, we can detect not only the known Trojan horses accurately, but also the novel ones. This approach has been implemented in Window system. We have evaluated our method with many experiments and the experiment results demonstrate the effectiveness of the approach.

This paper experimentally demonstrates error-free all-optical contention resolution of asynchronous, variable-length, and mix-data rate packets in optical-label-switching router networks. Time-to-live information triggers selective 3R regeneration in the router.

The extensive clayization of Dexing copper mine is responsible for water and soil pollutions because of the oxidation of sulfide minerals. During the clayization, harmful elements such as As, S, Sb and Pb could be effectively released into the clay and water. Using the abundant spectral information of short wave infrared (SWIR), combining with the spectral absorbed index, SAM (Spectrum Angle Mapper) which based on spectral matching, subtly compartmentalizes the degree of clay and distribution in copper mine.

We present an approach to decomposing branching volume data into sub-branches. First, a metric is proposed for evaluating local convexities in volumetric data, and it is a criterion for global selection of tip points. Second, a multi-path growing strategy is adopted to segment the volumes based on a DFS transformation starting from the tips. Experiments show that this approach is capable of generating desirable components and reasonable segmentation boundaries of a volume.

We demonstrate an all-optical clock-and-data recovery technology for 10-Gb/s NRZ-DPSK signals. With a relatively simple configuration, the clock-recovery scheme achieves less than 1.5-ps RMS jitter for signals after fiber transmission. The pattern-dependence of data-recovery is within 0.5-dB at BER10-9.

We propose and experimentally demonstrate an optical-TTL-based selective-3R regeneration scheme in an OLS testbed with fiber transmission. This scheme cognitively employs 3R when necessary. The experiment achieves burst mode clock recovery and error free operation.

We demonstrate optical-TTL-based selective-3R regeneration in an OLS testbed with OLS routers, which intelligently apply 3R only when necessary. The experiment achieves error-free operation with all-optical burst-mode clock recovery.