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Pilot spoofing attack (PSA) is a kind of active eavesdropping, which launches the identical training sequence to manipulate the channel estimation outcome during the pilot training phase. The newly proposed intelligent reflecting surface (IRS) system is vulnerable to the PSA because it relies on the pilot-assisted channel estimation methods to obtain channel statement information (CSI). To combat PSA in IRS-assisted systems, we consider two significant challenges: 1) channel distribution information (CDI) is uncertain, which will make the PSA detection methods based on the statistic feature (SF) invalid; 2) the noise is uncertain when detecting PSA in practical scenarios, which would impair the popular energy-based detectors. In this paper, we design a three-step training (TST) scheme. The effective detector could achieve reliable detection performance by examining the transmitter's received signal power levels when PSA occurs. The proposed method does not require the prior knowledge of noise variance and could obtain the CSI of both legitimate and illegitimate dyadic backscatter channels. Theoretical analysis and numerical simulations are presented further to demonstrate the efficiency of our proposed TST scheme.

Aiming at the problem that optical coherence tomography (OCT) images with low contrast and layer structure blur are difficult to be automatically layered, a new OCT detection method based on complex shearlet transform is proposed. The method utilises nearly optimal sparse approximation singular curves of multi-scale shearlet transform, and the contrast invariance of the phase congruence method. Compared with the Canny edge detector and wavelet methods, the complex shearlet-based method achieved the highest Pratt figure of merit (PFOM) value. The PFOM value of a step type edge is 0.92, and that of a pulse type edge is 0.98. Three types of OCT images were tested, including normal retinal macula area, dry age-related macular degeneration, and Stargardt disease. The experimental results show that the complex shearlet-based method can detect more layered structures of OCT images, especially the boundary between the ganglion cell layer and the inner plexiform layer that is difficult to detect, and it can detect various types of OCT images. The complex shearlet-based transform method provides an effective and general way to measure retinal OCT images.

In order to reveal the process of insulation destruction of circuit breaker in GIS under lightning impulse voltage, a new method of transient insulation numerical analysis is described in this paper. A combination of the electromagnetic transient analysis method and optimised charge simulation method (CSM) was put forward to calculate and analyse the transient insulation characteristics of 550 kV circuit breaker in GIS under lightning impulse voltage. The results show that, within 0–15 μ, though the voltage of circuit breaker did not reach its peak, there is severe electric field distortion caused by sharp change of voltage with a high probability of circuit breaker insulation breakdown. In addition, as for the circuit breaker insulation structure optimisation design, it is advisable to restrain the change rate of electric field strength amplitude so as to reduce the probability of insulation breakdown, rather than simply verify insulation structure by using maxi-mum electric field strength as the voltage input parameters of the electrostatic field under the power frequency in accordance with the traditional insulation analysis method, with the purpose of ensuring the circuit breaker can operate safely and reliably for a long time.

This letter proposes a novel pilot spoofing attack detection scheme by introducing an auxiliary node as a trusted user, which also participates in the uplink training process and assists to detect pilot spoofing in multiple-input single-output systems. To do so, we design an efficient three-phase uplink training method, with which a malicious user can be reliably detected. In contrast to the existing methods involving two-stage uplink–downlink training, our method relies only on the uplink training stage. Meanwhile, our new scheme detects spoofing attack without altering pilot signals, which is also beyond the competence of the existing methods. Numerical results show that our method improves the detection probability significantly.

In this paper, an dual linearly orthogonal polarized antenna based on turnstile orthomode transducer (OMT) is presented. The unified impedance bandwidth of the proposed antenna is 29.3% from 122GHz to $164\text{GHz}(\mathrm{S}11 . Moreover, the isolation of transceiver and receiver is above 75dB. The proposed antenna realizes dual orthogonal polarized radiation, and the far-field cross-polarized gain is below −50dB. The proposed antenna can be used as feed for single station RCS measurement system. And it can be applied in Compact Antenna Test Range.

AIMS: Statin-related myopathy (SRM), which includes rhabdomyolysis, is an uncommon but important adverse drug reaction because the number of people prescribed statins world-wide is large. Previous association studies of common genetic variants have had limited success in identifying a genetic basis for this adverse drug reaction. We conducted a multi-site whole-exome sequencing study to investigate whether rare coding variants confer an increased risk of SRM.METHODS AND RESULTS: SRM 3-5 cases (N = 505) and statin treatment-tolerant controls (N = 2047) were recruited from multiple sites in North America and Europe. SRM 3-5 was defined as symptoms consistent with muscle injury and an elevated creatine phosphokinase level >4 times upper limit of normal without another likely cause of muscle injury. Whole-exome sequencing and variant calling was coordinated from two analysis centres, and results of single-variant and gene-based burden tests were meta-analysed. No genome-wide significant associations were identified. Given the large number of cases, we had 80% power to identify a variant with minor allele frequency of 0.01 that increases the risk of SRM 6-fold at genome-wide significance.CONCLUSIONS: In this large whole-exome sequencing study of severe statin-related muscle injury conducted to date, we did not find evidence that rare coding variants are responsible for this adverse drug reaction. Larger sample sizes would be required to identify rare variants with small effects, but it is unclear whether such findings would be clinically actionable.

How to describe the compression creep behavior of gangue is very essential for the design of gangue backfilling mining. In this paper, compression tests of two kinds of gangue are studied, finding that logarithmic function is suitable for describing its equal-time stress–strain relationship. Stress–strain–time relationship is proposed through modifying the Singh–Mitchell creep model based on the analysis of the test result, and this model can provide a design basis for gangue backfilling technology. Back analysis indicates that this model can basically describe the creep behavior of gangue with a few parameters that are easy to be determined. This research can provide a reference on the design of gangue backfilling mining, and on the subsidence value estimation.

A flexible, stable and controllable real-time algorithm of Auto-Regressive and Moving Average based on Swing Door Trending (ARMA-SDT) is proposed for the compression of impact-type signals in gear fault detection systems. The Auto-Regressive and Moving Average (ARMA) model is used to predict the variation trend of signal features. To guarantee the adaptability, an empirical equation is proposed to calculate the compression threshold of the Swing Door Trending (SDT). Based on the empirical equation and prediction results, dynamic self-regulation of compression threshold is realized, and the compression error always stays around a preconfigured value. Moreover, an experimental setup and an engineering solution are proposed to verify the usefulness, reliability, and stability of the proposed ARMA-SDT algorithm in data compression.

A number of problems may arise from architectural requirements modeling, including alignment of it with business strategy, model integration and handling the uncertain and vague information. The paper introduces a method for modeling architectural requirements in a way of ontology-based and capability-oriented requirements elicitation. The requirements can be modeled within a three-layer framework. The Capability Meta-concept Framework is provided at the top level. The domain experts can capture the domain knowledge within the framework, forming the domain ontology at the second level. The domain concepts can be used for extending the UML to produce a domain-specific modeling language. A fuzzy UML is introduced to model the vague and uncertain features of the capability requirements. An algorithm is provided to transform the fuzzy UML models into the fuzzy Description Logics ontology for model verification. A case study is given to demonstrate the applicability of the method.

Ongoing advances in digital-array technology have led to the development in fields such as radio astronomy, radar, and deep-space exploration. In this paper, we introduce the world's largest synthesis radio telescope, the Square Kilometer Array (SKA), and new-generation radio-telescope devices. We analyze the characteristics and performance advantages of digital-array system architecture in radio telescopes. We discuss in detail three kinds of low-frequency aperture-array system architecture based on the SKA work package in KLAASA, and we present a practical system scheme.

Grid connection of distributed generation would have a certain impact on safe and stable operation of receiving-end network, so systematic analysis on it would be significant. The method for comprehensive assessment on effects caused by grid connection of distributed generation on power grid is presented. The assessment system is divided into steady-state operation assessment, reliability assessment, and power quality assessment. Steady-state operation assessment is consisted of reactive power demand analysis, delivery capacity analysis, and voltage level analysis. The effects of grid connection of wind farm, different schemes comparison, penetration power, and average wind speed to grid reliability are analyzed. Voltage deviation, voltage fluctuation flicker, harmonic, and three-phase voltage imbalance indexes are used to evaluate the effect to power quality. Specific indexes values are used to measure extent of impact are given and relevant assessment software is developed. Impacts of distributed wind power on Qingdao power grid is analyzed, by taking grid connection of Qingdao Jimo Wind Farm as an example, from the aspects of stable operation, reliability and power quality, etc. and its extent of impact is assessed in a quantitative way, therefore it has guiding significance on power grid planning and operation.

A new approach for the computation of electric fields is described, based on the response surface methodology(RSM) and geometric feature charge simulation method (GFCSM). And the novel combination of RSM and GFCSM is applied to calculate the electric field of the high voltage SF6 arc quenching chamber in this paper. The electric field distribution with higher calculation precision has been achieved. The results of the comparison between the conventional and proposed techniques are presented. Moreover, the new approach proves to be more efficient, minimizing computation of the electric field with multi dielectric medium.

This paper presents a non-contact manipulation method using rotational flow generated by high speed motion of a glass needle. In order to generate an applicable motion that can precisely control the speed and position of a target object around an end effector, a manipulator actuated by three piezoelectric actuators is proposed. A compact parallel link produces precise three-dimensional motions. To reach the required end-effector frequency and amplitude, which is necessary for generating the rotational flow that can make rotational movement of microbeads having patterned data, the end effector motion is generated by controlling the three piezoelectric actuators at high speed. In this paper, we focus on rotational flow created by two-dimensional circular motion of the end effector mounted on the parallel link. By changing the amplitude and frequency of the circular motion, the generated swirl flow is analyzed in 3D space using 9.6-μm microbeads. We analyzed the velocity toward to the root of the end effector and angular velocity around the end effector by formulating models. From the analyzed data, we verified that the rotational flow has potential to manipulate micro-objects precisely in 3D space.

A new approach for the computation of electic fields is described, based on the response surface methodology (RSM) and geometric feature charge simulation method (GFCSM). And the novel combination of RSM and GFCSM is applied to calculate the electric field of the high voltage SF 6 arc quenching chamber in this paper. The electric field distribution with higher calculation precision has been achieved. The results of the comparison between the conventional and proposed techniques are presented. Moreover, the new approach proves to be more efficient, minimizing computation of the electric field with multi dielectric medium.

We present a real-time error-compensation method which is used to improve the measurement precision of a Scheimpflug range sensor. Based on this method a Scheimpflug range sensor is fabricated. It only takes 3.21 ms to complete one distance measurement in a hardware test. Furthermore, by using this range sensor, an altitude-holding application is performed on a proof-of-concept flight test platform in the lab environment. The hardware-in-loop (HIL) simulation result shows that approximately 10 mm control accuracy is achieved by implementing the error compensation.

The purpose of this paper is to exploit compressive sensing (CS) method in dealing with electrocardiography (ECG) and electroencephalography (EEG) signals at a high compression ratio. In order to get sparse data of ECG and EEG signals before being compressed, a combined scheme was presented by using wavelet transform and iterative threshold method; then, compressive sensing is executed to make the data compressed. After doing compressive sensing, Bayesian compressive sensing (BCS) is used to reconstruct the original signals. The simulation results show that compressive sensing is an effective method to make data compressed for ECG and EEG signals with high compression ratio and good quality of reconstruction. Furthermore, it shows that the proposed scheme has good denoising effects.

A number of recent epidemiologic and experimental studies have enhanced our knowledge of the etiology and pathogenesis of chronic urticaria (CU), a disease that imposes profound impairment on patient's quality of life. Our study was performed to explore the relation between autoimmunity (CU) and the levels of plasma prothrombin F1+2. Thirty four (CU) patients with positive autologous serum skin test (APST) their F1+2 were measured by ELISA at pre and post therapy. The levels of F1+2 in autoimmunity (CU) patients have been decreased obviously after treatment (3.34±2.87vs 0.94±0.58, p 0.05).

The HIV/AIDS epidemic has affected the world over the past two decades reveals the significant role of socio-cultural beliefs and attitudes in the shaping of people’s lifestyles and approaches to the control and prevention of epidemics. A descriptive analysis of Voluntary Counseling and Testing (VCT) in the 2005–2006 which is the key Hubei provincial science and technology project that studies about HIV status in Hubei province, investigates relevance among common STD and HIV regional population, explores about HIV from the STD patient to the general population’s diffuse pattern and transfer rule, promulgates the epidemic status of AIDS in Hubei province, formulates the practical feasible strategies for the government to guard against AIDS and provide policy-making basis, further promotes the improvement and development of VCT services. To carry out statistical analysis for AIDS amongst Voluntary Counseling and Testing personnel, and HIV/AIDS patients epidemic and clinical data. Voluntary Counseling and Testing of the 1,553 cases detected 37 cases of HIV/AIDS patients in those volunteers, there is high proportion of unhealthy sexual contact, blood/blood products transfusion and the history intravenous drug abuse.

Accurate evaluation of the failure evolution of the overlying strata after multiple mining actions is of great importance both for the prevention of water disasters and the mining designs. To ensure the safety of mining multiple coal seams, the fracture criterions of overlying strata after mining actions were established on the basis of beam theory as well as the influences of coal seam spacing, face size, and lithology on the increased heights of failure zones after each consecutive mining sequence. A newly developed device, named electric controlled water flow detector, and its detecting procedure, was introduced. In situ investigations were performed in the Gaojialiang and Jinhuagong Mines, China. Results showed that the mining of a lower coal seam does not change the failure evolution of the roof strata of the upper coal seam when the coal seam spacing is large. The larger the mining height of the lower coal seam is, the more fractures the overlying strata of the upper coal seam have, and the larger the height of the failure zone. In addition, the failure extent of overlying strata caused by coal face mining increased with their hardness. It was found that the electric controlled water flow detector can effectively detect the failure evolution during multiple mining actions, with high water plugging effectiveness and detection accuracy.

A cloud computing virtual resource leasing algorithm considering about extreme price filtering has been proposed in this paper, which realises optimal selection for handling leasing price for task virtual machine. First, three-function module cloud composed of virtual resource provider, cloud service provider and final user has been adopted to calculate environment and list calculation target for virtual resource leasing profit; second, distribution and task urgency of price has been fully considered. For weakly stationary price sequence, outlier detection method has been adopted to make extreme price filtering. At the same time, weak equilibrium operator has been designed, exponential function has been used to control the overall shape of curve, non-uniform mutation operator has been used to make local operating adjusting, realise effective prediction for price in the future and optimal selection and make optimal selection for handling leasing price of task virtual machine.

The addition of graphite powder in conventional asphalt mixture can produced asphalt concrete with excellent electrical performance. Percolation theory was employed to discuss the relation between the conductivity and graphite content of graphite-modified asphalt concrete. It was found that the results of percolation model are consistent with experimental values. The percolation threshold of graphite-modified asphalt concrete is 10.94% graphite content account for the total volume of the binder phase consisting of asphalt and graphite. The critical exponent is 3.16, beyond the range of 1.6–2.1 for the standard lattice continuous percolation problem. Its reason is that the tunnel conduction mechanism originates near the critical percent content, which causes this system to be not universal. Tunnel mechanism is demonstrated by the nonlinear voltage-current characteristic near percolation threshold. The percolation model is able to well predict the formation and development of conductive network in graphite-modified asphalt concrete.

Compared with the mode of information interaction among command and control (C2) deciders in the traditional high centralized hierarchical structure, the mode of information sharing and fusion in distributed structure has many different features to adapt the information grid environment. The key problems are information visualization, decision preference aggregation and information exchange. Accordingly, a concept of information component, an aggregating algorithm based on linguistic methods, and a way of information exchange through SNS (Social Network Services) are proposed to solve above problems.

In the microwave system it is very important to the manufacture of MEMS microstrip array antennas, microstrip array antenna's geometrical parameters are closely related to its electrical parameters. In the manufacturing process of MEMS, it is very difficult to measure the geometry parameters. However, currently it is easy to test the electrical parameters of microwave systems. The real geometry parameters of the microstrip array antenna were obtained through the simulation results of HFSS software and the testing results of microstrip array antenna's electrical parameters. The geometrical dimension error of the microstrip antenna's structure is determined. In this paper, according to the analysis and test results of C-band microstrip array antenna, the inversion law in the microstrip array antenna manufacturing is obtained.

Status of wind power's development and accommodation is introduced in Shandong power grid. Available capability of accommodating wind power in spring of 2013 is analyzed under the condition of load, power interchange, generation and power grid prediction. Based on wind power prediction, actual wind power accommodation capability is carried out through wind power restriction caused by constraint of power transfer and peak-load regulation. Finally, the corresponding countermeasures are proposed in aspects of technology, management and planning according to the actual condition of Shandong power grid.

The developing trend of the electrical vehicle recharging service network is analyzed in a reasoning calculation method for the coming several years. To simulate the developing conditions of related factors, some fitting prediction models are proposed based on the statistical data of the last several years. They are China's automobile increasing model, China's electrical vehicle increasing model, electricity price prediction model, and so on. Also, the configuration, investment, and revenue model of the electrical vehicle recharging service networks are proposed. We select Jinan as a typical city to make a calculation for service networks' development. And we draw the conclusion that the service network will get refunding till 2017 to 2020.

Background: Postherpetic neuralgia (PHN) is often refractory to existing treatments. Pulsed radiofrequency (PRF) is known to be effective for treating neuropathic pain. In common, the targets of PRF treatment were the segmental dorsal root ganglion (DRG) neurons responsible for the pain. A potential complication that can occasionally occur with PRF treatment is damage to the adjacent tissue and organ. The effectiveness of the angulus costae as a puncture site for PRF has not been tested in thoracic PHN treatment. Objective: The goal of this study was to investigate the therapeutic efficacy and safety of PRF for treating thoracic PHN through the puncture of the angulus costae. Study Design: Prospective, randomized, double-blinded study. Setting: Department of Anesthesiology, Xinhua Hospital, Shanghai Jiaotong University School of Medicine. Methods: Ninety-six patients with thoracic (T2-11) PHN were equally randomized assigned into 2 groups. The electrode needle punctured through the angulus costae of each patient guided by x-ray; PRF at 42°C for 120 seconds was applied after inducing paresthesia involving the affected dermatome area. PRF was applied in the PRF group (n = 48) twice. It was also applied in the sham group (n = 48) twice without radiofrequency energy output. The treatment was done once a week for 3 weeks. Tramadol was used for flare pain when the visual analog scale (VAS) ≥ 3. Outcomes Assessment: The therapeutic effect was evaluated by VAS, SF-36 health survey questionnaire, side effects (type, frequency, and onset time) before treatment, at days 3, 7, and 14, and at months one, 2, 3 and 6 after PRF. The average of tramadol (mg/d) administrated within the first month after treatment was also recorded. Results: The postprocedure VAS scores in the PRF group were significantly lower than those in the sham group and lasted for 6 months after treatment (P < 0.05). The SF-36 score, such as physical functioning, physical role, bodily pain, general health perceptions, social function, emotional role, and mental health index were significantly improved until 6 months after treatment in the PRF group compared to the sham group (P < 0.01-0.05). The average dosage of tramadol administered (mg/d) within the first month after treatment was also significantly reduced in the PRF group compared to the sham group (P < 0.05). There were no obvious signs of pneumothorax, bleeding, infection, or other severe side effects in either group (P > 0.05). Limitations: Single center study, relatively small number of patients. Conclusions: The strategy that the angulus costae be used as the PRF puncture point of an electrode needle and the final localization of the needle tip as determined by sensory testing is an effective and safe therapeutic alternative for thoracic PHN treatment. Benefits include that the procedure is minimally invasive, provides short-term pain relief, and improves quality of life. Clinical Trial Registration: NO ISRCTN25588650. Key words: Thoracic, postherpetic neuralgia, pulsed radiofrequency, angulus costae