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This paper investigates the system security problem of cyber-physical systems (CPSs), which is not only more practical but also more significant to deal with than the detecting faults problem. The purpose of this paper is to find an optimal attack strategy that maximizes the output error of the attacked system with low energy consumption. Based on a general model of linear time-invariant systems and a key technical lemma, a new optimal attack strategy for the meticulously designed false data injection attack is constructed. It is worth mentioning that compared with the existing model-based attack strategies, the designed one is more general and the corresponding attack strategy is more easily implemented when system states and external input are inaccessible. Key to overcoming the inaccessible information, a dynamic observer in the form of Luenberger is constructed. Finally, a networked magnetic levitation steel ball movement system is applied to illustrate the effectiveness of the proposed scheme.

Different indices have been used to reflect, or monitor the ionospheric scintillation, e.g. the detrended carrier phase, σφ, S4, the rate of change of the vertical total electron content index (vROTI), as well as the ionosphere‐free linear combination (IFLC) of two carrier phases. However, few studies have been performed to investigate the refractive and diffractive contributions to these indices, especially during geomagnetic storms. In this study, we analyze the high-resolution (50 Hz) phase and amplitude measurements from four high-latitude stations in Svalbard, Norway during the geomagnetic storm on 7–8 September 2017. Our results show that at high latitudes, the high-pass filter with a standard cutoff frequency of 0.1 Hz sometimes cannot effectively remove the refraction-driven phase variations, especially during the geomagnetic storm, leading to a remaining refraction contribution to the detrended carrier phase and σφ when scintillation happens. In the meanwhile, as vROTI is sensitive to the TEC gradients, regardless of small- or large-scale ionospheric structures, both refraction and diffraction effects can cause visible fluctuations of vROTI. For most of the scintillation events, the phase indices (including detrended carrier phase, σφ, and vROTI), IFLC, and S4 show consistent fluctuations, indicating that diffraction usually occurs simultaneously with refraction during scintillation. One interesting feature is that although the IFLC and S4 are thought to be both related to the diffraction effect, they do not always show simultaneous correspondence during scintillations. The IFLC is enhanced during the geomagnetic storm, while such a feature is not seen in S4. We suggest that the enhanced IFLC during the geomagnetic storm is caused by the increased high-frequency phase power, which should be related to the enhanced density of small-scale irregularities during storm periods.

Due to the particularity of raw materials and the complexity of processes, the petroleum and petrochemical industry involves a variety of disaster risks in production, transportation, storage and etc. However, there are three barriers in the emergency rescue of the petroleum and petrochemical industry, scene separation, data isolation and inefficient coordination. No matter the application of existing technology or the proposed method and concept, the situation cannot be broken quickly. By analyzing these problems existing in 5G communication technology, artificial intelligence and petroleum and petrochemical emergency rescue, this paper puts forward the concept of petroleum and petrochemical remote collaborative emergency technology, analyzes the development trend of remote collaborative emergency technology, and prospects the petroleum and petrochemical emergency rescue technology.

The purpose of this paper is to study consumer service-oriented APP and try to build a theoretical framework of its impact on urban space. The Physical space space when consumers use APP is defined as “window space”. Based on constructing the dynamic mechanism for the reorganization and diffusion of consumer service-oriented APP, this paper puts forward the hypothesis that “window space” gathers the physical space of service industry. Focusing on the spatial development in the Internet era, this paper predicts the transformation of urban space from “business center” to “crowd center”.

The setting direction of the evaluation indicators in the current research and the differences of the research methods in terms of principles, advantages and disadvantages and applicability are compared and analyzed. The results show that the current well-facilitated farmland construction has achieved remarkable results. In the suitability evaluation research before project construction, the setting of evaluation indicators focuses more on the natural endowment conditions of regional cultivated land; in the benefit evaluation research after project construction, from The early focus on economic benefit evaluation has gradually developed into an equal emphasis on economic, social and ecological benefit evaluation; in the analysis of influencing factors, the current research is still relatively weak, and there are still few explanations for the differences in the level of benefit improvement in different construction areas. Regarding research methods, future research should comprehensively consider the advantages, disadvantages and applicability of different methods. This study can provide a useful reference for scientifically promoting well-facilitated farmland construction.

The occurrence and development of erosion gully will increase the area of soil erosion and continuously erode the cultivated land. The treatment of erosion gully is swing in the black soil region of Northeast China. However, they are all directed at the typical black soil area, while the soil erosion caused by the erosion gully in the semi-arid area of Northeast is less concerned. The study uses a combination of RS and census data. Exploring the number of erosion gully and the status of development, The survey results show that :the number of erosion gully is large, and most of them are developmental erosion gully. If the governance measures are not taken in time, the erosion ditch may continue to develop.

The Spectre attacks exploit the speculative execution vulnerabilities to exfiltrate private information by building a leakage channel. Creation of a leakage channel is the basic element for spectre attacks, among which the cache-tag side channel is considered to be the most serious one. To block the leakage channels, a novel cache applies Dynamic Mapping technology, named DmCache, is presented in this paper. DmCache applies a dynamic mapping mechanism to temporarily store all the cache lines polluted by speculative execution and keep invisible when accessing. Then it monitors the head of the reorder buffer to determine which polluted cache line can become visible. In this paper, we demonstrated that Spectre attacks exerted no impact on a processor system equipped with DmCache based on the analysis of the processor’s circuit behaviour, which equipped with the DmCache and under the Spectre attack.

An on-chip debugging method based on the RISC-V processor is introduced, which simplifies the complicated debugging operation into instructions and improves the debugging efficiency effectively. The method adopts a JTAG interface to realize the debugging functions of the processor, such as running control, software breakpoint, hardware breakpoint and single-step execution. The method was verified by simulation at the RTL level, and the logic synthesis was carried out in SMIC 180nm process library.

In recent years, the safe and stable operation of natural gas pipeline has become the focus of the whole society. Long distance natural gas pipelines are mostly large-diameter and high pressure pipelines, so their safe operation is particularly critical. In the high-pressure natural gas pipeline transportation industry, the wall thickness of key points (elbows and tees) will be thinned due to long-term erosion of gas, resulting in serious consequences. Therefore, its wall thickness monitoring is a key work of long-distance natural gas pipeline operation units. At present, most of them adopt off-line monitoring, but the standardized monitoring cycle cannot be effectively determined, and there are no relevant standards in the industry. The author uses fluent simulation software to establish the model, and then modifies the model combined with the field data. Then, the model is used to analyze the influencing factors of key points (elbow and TEE) one by one, and select more important influencing factors to formulate the monitoring cycle of different points. The monitoring cycle can provide reference for the daily work of on-site operators, and then ensure the safe and stable operation of long-distance natural gas pipeline.

Warm air supply is widely used to condition indoor environment in winter. It has been proved that stratum ventilation (SV), as a novel air distribution, has potentials to be applied for heating. The outlet location may affect indoor air quality (IAQ) due to interaction between thermal plumes from heat sources and room airflows. In this study, the effect of outlet location on IAQ for SV was investigated for 9 cases under heating mode. The outlets were located at the heights of 0.4 m on the same side wall as the inlet, 0.4, and 1.3 m on the opposite side wall, respectively. The concentration of carbon dioxide was measured in an experimental chamber with dimensions of 5850 mm(L) × 5057 mm(W) × 2554 mm(H). The average concentration of carbon dioxide and carbon dioxide removal efficiency (εCRE) were used as the evaluation indexes. The results showed that the concentration of carbon dioxide in the breathing zone with the outlet located on the same wall as the inlet was lower than those with the outlets located on the opposite side wall. At this scenario, εCRE was greater than one, showing a good ventilation performance.

An optofluidic laser based on a hollow-core negative-curvature fiber (HC-NCF) is proposed and demonstrated. The submicron-thick circular capillary tubes embedded in the cladding of the HC-NCF act as antiresonant elements and are used as both a resonator and dye microfluidic channels. A stable optofluidic dye laser with a low threshold of 15.14 nJ/mm2 is achieved. The laser is compact and robust and exhibits directional output.

An ultra-wideband metal antenna with low radar cross section is proposed. The antenna adopts the metal Vivaldi as the radiation element, and utilizes a new-type frequency selective surface structure to reduce the radar cross section within the working frequency band. The frequency selective surface structure is composed of three layers of periodic planar structure and double layer medium, which has the characteristics of ultra wide bandwidth and controllable bandwidth. By changing the slot width and the width of the middle layer metal structure, can adjust the working frequency bandwidth and center frequency of the frequency selective surface structure, so as to realize the frequency bandwidth is adjustable, which can be used to reduce radar cross section of the antenna in different working frequencies.

A theoretical model of a vibrating electret electrostatic energy harvester for a double-ended fixed beam was established herein for a low-frequency vibration energy in the environment. The key parameters of the electrostatic energy harvester were optimized by a MATLAB/Simulink numerical analysis. The relationship between the output power, resonant frequency, and half-power bandwidth and the electret surface potential, air gap, and load resistance was also studied. The magnitude of the external excitation acceleration and the size of the electret remained constant. The numerical results are as follows:(1) the existence of an optimal surface potential makes the output power of the electrostatic energy harvester reach the maximum value. The soft spring effect gradually increases with the increase of the surface potential, making the resonant frequency of the energy harvester device shift. The bandwidth also gradually increases. (2) An optimal initial air gap maximizes the power when the surface potential is constant. The half-power bandwidth decreases as the gap increases. (3) An optimal load maximizes the power when the surface potential and the air gap remains constant. The resonant frequency is offset as the load decreases. (4) An optimal load is used to maximize the half-power bandwidth when the air gap is constant. The larger the surface potential, the greater the half-power bandwidth under the same load. Experiments show that the output characteristics of the energy harvester under different load resistances have the following characteristics:with the increase of the load resistance, the output power and the half-power bandwidth increase at the beginning, then decrease. The maximum output power is 0.188 mW when the load resistance is 90 MΩ. In addition, the half-power bandwidth reaches the maximum value of 4.7 Hz when the load resistance is 330 MΩ.

[Objectives] One-way periodic stiffened plates are widely used in ship structures, and their vibro-acoustic characteristics provide a theoretical reference for the analysis and optimization of the sound and vibration characteristics of stiffened plates.[Methods] Considering the force and torque of the stiffeners to the plate, along with the coupling effect between the fluid acoustic medium and the plate, a structural dynamic model of infinite one-dimensional and two-dimensional periodically stiffened plates is established. The spatial domain is transformed into a space wave number domain using the Fourier transforms method. The vibration equation of the stiffened structure is deduced using the constructor, Poisson's formula and periodic function. The analytical solution of the motion equations of typical periodic stiffened plates is obtained and calculated under a time-harmonic point force or harmonic excitation. Combined with the stationary phase method, the far field radiated sound pressure can be obtained. The influence of the torque of the stiffener, excitation types, excitation locations, plate thickness, periodicity spacing and parameters of stiffeners on the sound radiation characteristics of three different models of periodic stiffened plates are numerically quantified.[Results] The torque of the stiffener has a lesser effect on structural vibration characteristics. The influence of the stiffener parameters on the phonon crystal band gap can be used to attenuate the vibration at certain peak frequencies. The excitation load on the strong structural components can effectively weaken the vibration. The periodicity spacing and parameters of the stiffeners have obvious effects on structural vibration characteristics.[Conclusion] The underwater acoustic vibration characteristics of reinforced plate structures can be effectively optimized by the reasonable setting of the excitation types and parameters of the stiffeners.

In order to achieve home intelligence, this paper introduces an interactive system of intelligent cloud home based on CC3200 Wi-Fi microcontroller unit(MCU), WeChat official account and Ali cloud server. Users can not only control household equipment by WeChat official account remotely，but also get the status of sensors. The paper provides an overall design scheme and introduces the hardware component of system. It also gives the software design of CC3200 MCU, WeChat official account and Ali cloud server. Experiments results show that the proposed system runs steadily, has better user experiences，and has high application value.

In order to analyze the stability of the thin-walled milling system, a continuous beam model of spindle tool workpiece system is established, from which, the equivalent mass and stiffness are obtained from the end of cutter and workpiece, respectively. The influences of workpiece sizes on milling stability of the system are researched consequently. The results show that the cross sectional width and height of thin walled workpiece has non-negligible influences on the milling stability. Among them, the height has greater impact, for a small height value pulls down the critical cutting depth severely. With the increase of the cross sectional height of workpiece, critical milling depth improves obviously. It is also noted that as the first natural frequency of the workpiece is close to or even greater than that of the spindle-cutter system, the workpiece’ shape has not significant influence on the milling stability. These above results can provide a theoretical basis for the stability machining for thin-walled parts.

Halogen bond, as hydrogen bond, is a non-covalent bond. Dynamic nuclear polarization (DNP) technique has been used previously to study hydrogen bonds-mediated intermolecular interactions. However, no study has been carried out so far to study the halogen bond-mediated intermolecular interactions with DNP. In this work, 19F DNP polarization efficiency of the halogen bonds existing in supramolecular assembling by 4-OH-TEMPO and 1,4-diiodotetrafluorobenzene (DITFB) was studied on a home-made DNP system. The formation of intermolecular halogen bonds appeared to increase 19F DNP polarization efficiency, suggesting that the spin-spin interactions among electrons were weakened by the halogen bonds, resulting in an increased T2e and a larger saturation factor.

Two new zinc complexes, [Zn(Ppd)I]ClO ( I) and [Zn(Ped)I]ClO ( II), where Ppd and Ped are the Schiff bases N, N′-bis[(1-(2-pyridyl)ethylidene)propane-1,3-diamine and N, N′-bis[(1-(2-pyridyl)ethylidene)ethane-1,2-diamine, respectively, have been synthesized and characterized by means of elemental analysis, infrared spectroscopic, molar conductivity, and single crystal X-ray diffraction. The crystal of I is tri-clinic: space group $$P\bar 1$$ a = 8.421(2), b = 9.143(2), c = 13.166(3) Å, α = 92.521(5)°, β = 94.498(3)°, γ = 94.232(4)°, V = 1006.6(4) Å, Z = 2. The crystal of II is triclinic: space group $$P\bar 1$$, a = 8.219(1), b = 8.483(1), c = 14.733(2) Å, α = 80.058(1)°, β = 81.960(1)°, γ = 89.300(1)°, V = 1001.8(2) Å, Z = 2. The zinc atom in the complexes assumes a distorted square pyramidal geometry through coordination by two pyridine N atoms and two imine N atoms of the Schiff base at the basal plane, and by a I atom at the apical position. [ABSTRACT FROM AUTHOR]

By chemical composition analysis, X-ray diffraction (XRD), optical microscopy, scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS) and other measurements, the process mineralogy of Jinchuan nickel slag in a settlement furnace was studied, including the mineral composition, structure, embedded features, distribution of Fe, Ni, Cu, and Co. The results show that the phase composition of the slag includes hortonolite and glass, a few Cu-Ni sulphide, chalcocite and magnetite. The structure of the slag is single, and the Cu-Ni sulphide is distributed in the silicate irregularly. The irons are mainly located in the hortonolite, nickel and copper are mainly located in the Cu-Ni sulphide, and there is no independent minerals about cobalt, which is in the form of isomorphism in other minerals. The recovery of valuable metals from the slag can use deep reduction process or hydrometallurgy.

There is a significant impact of ablation angle on the anti-ablation performance of C/C composites. A self-designed oxygen-kerosene ablation system was employed to study the ablation behavior and mechanism of C/C composites. Typical ablation angle of the experiment was 90°, 60°, 45° respectively, and particle concentration of the gas-solid two-phase ablation flow was 1.37%. The microstructure of post-test samples was observed with the scanning electron microscope(SEM), and the ablation rate of samples was also calculated. The result shows that when the ablation angle is 90°, 60°, 45°,the corresponding mass ablation rate for ablation experiment is 0.146,0.123,0.100g/s respectively. With the decrease of ablation angle, the mass ablation rate of samples is decreased gradually; while for the samples affected by particle erosion, the corresponding mass ablation rate is 0.452,0.455,0.432g/s and the line ablation rate is 1.863,1.323,0.843mm/s. The mass ablation rate is approximately unchanged and the line ablation rate is decreased. The smaller the ablation angle is, the more serious the thermalchemical ablation of gas, and thus increase the erosion area of axial fiber bundle under ablation condition and ablation gradient of radial fiber under ablation/erosion condition.

The large PV medium-voltage (MV) DC power collection system is more efficient than the traditional AC collection system, which provides an alternative for future PV applications. As one of the core components of the PV MVDC power collection system, key techniques of DC transformer are presented here in detail, including the technical requirements, and fault operation analysis in the DC collection system. When part of the PV DC module in the low-voltage (LV) side of DC transformer fails and bypassed, the DC collection system continues working normally with only part of power lost. When the MV side of DC transformer is shorted, all the PV modules exist and the collection system splits without ride-through techniques. The fault operation principle of DC transformer in PV MVDC power collection system is verified by simulations.

Compared with the traditional reactor abnormal state detection method, the acoustic vibration detection method combines the advantages of acoustic detection and vibration detection, which has the advantages of simple installation, strong portability and good signal integrity, and has a broad application prospect. In this paper, the characteristic parameters of reactor acoustic vibration, including sound pressure level, sound power level, acoustic signal spectrum, vibration amplitude, vibration acceleration value, vibration signal spectrum, harmonic proportion and frequency complexity, are obtained to analyze the range and distribution rule of each characteristic parameter under long-term operation condition of reactor, and the weight factor of each characteristic parameter is determined by analytic hierarchy process On the basis of fuzzy reasoning, the state evaluation model of reactor is established.

Although the state evaluation method based on characteristic parameters and weight factors can extract the characteristic quantities in time domain and frequency domain according to the collected acoustic and vibration signals of reactors, it is necessary to analyze a large number of test data to establish the functional relationship between the characteristic quantities and the defect states, and to establish the function relationship between the characteristic quantities and the defect states, and to establish the function relationship between the characteristic quantities and the defect states The method can directly learn the data samples, and self-study the correlation rules of characteristic parameters and defects through the training of neural network. In this paper, the deep learning neural network model is constructed, and the data obtained from reactor defect simulation experiment and field measurement are used as samples to train the deep learning network. Through the training of neural network, the characteristics of acoustic vibration signal are automatically learned, and the characteristics are stored in the parameters of neural network. Finally, the state of reactor is realized by the classifier at the end of the network assessment

The architectural heritage of handcrafts of Zhenjiang has unrepeatable technological and historical values. This paper aims at obtaining a reliable overview of the occurrence of the kiln sites. Their characteristics and values as architectural heritage of handcrafts will be fully understanding, expounds the problems in the protection and utilization of those kiln sites, then gives different utilization strategies on the priority of the kiln site protection is put forward.

In the tunnel projects construction process of our country, there are many crossing karst areas situations. Advanced detection of abnormal geological bodies in karst areas is essential to ensure the safety of tunnel construction. This paper takes Guizhou Provonce Expressway Project—Xinjie Tunnel as an example. By studying the overall karst situation of Xinjie Tunnel, the basic principles of Ground Penetrating Radar detection and tunnel detection principles are explained. The detection methods and effects of the Side Walls and Small Targets are explained by real examples. Advanced detection of the abnormal geological bodies that may be encountered in the tunnel construction and trying to avoid the possible geological disasters in the tunnel construction process, are very important to provide guarantee for the safety of tunnel construction.

The development and key calibration methods of the sensors for the measurement and automatic monitoring of dissolved oxygen in seawater have always been the research focus in the field of Marine monitoring technology. This paper summarizes the measurement methods of dissolved oxygen in seawater, the working principle and advantages and disadvantages of different dissolved oxygen sensors, and the research on calibration methods of mainstream optical dissolved oxygen sensors. Especially for optical dissolved oxygen sensors with better stability, longer service life and stronger anti-interference ability, several laboratory calibration methods which have been developed and applied, as well as in situ calibration methods which are still in the research stage are analyzed.

Vertical compensation friction stir welding (VCFSW) was proposed in order to solve the adverse effect caused by a big gap at the interface between two welded workpieces. VCFSW was successfully applied to weld 6061-T6 aluminum alloy with the thickness of 4 mm, while 2024-T4 aluminum alloy was selected as a rational compensation material. The results show that VCFSW is difficult to get a sound joint when the width of strip is no less than 1.5 mm. Decreasing the welding speed is beneficial to break compensation strip into pieces and then get higher quality joint. When the width of strip is 1 mm, the tensile strength and elongation of joint at the welding speed of 50 mm/min and rotational velocity of 1,800 rpm reach the maximum values of 203 MPa and 5.2%, respectively. Moreover, the addition of 2024-T4 alloy plays a strengthening effect on weld zone (WZ) of VCFSW joint. The fracture surface morphology of joint consisting of amounts of dimples exhibits ductile fracture.

A self-designed oxygen-kerosene ablation system was employed to study the ablation mechanism and performance of the carbon-carbon composites. Particle concentrations of the gas-solid two-phase ablation flow were 0, 1.37%, 2.22%, and 2.64% respectively. The microstructure of post-test samples was analysed through the scanning electron microscope (SEM), and the ablation rate was calculated. The influence principle of particle concentrations on the ablation rate of the carbon-carbon composites was studied, and the mechanism of ablation was analysed. Experiment results show that with no particles involved the mass ablation rate is 0.159g/s and the linear ablation rate is 0.175mm/s, while with particles introduced, the minimum mass ablation rate and linear ablation rate are 0.432g/s and 0.843mm/s respectively, with the increase of particle concentrations, the ablation rate becomes accelerated. Particle erosion makes the ablation of sample seriously intensified, and the ablation gradient of radial fiber on erosion surface is increased with the increase of particle concentrations as well.

In order to eliminate the flash, arc corrugation and concave in weld zone, level compensation friction stir welding (LCFSW) was put forward and successfully applied to weld 6061-T6 aluminum alloy with varied welding speed at a constant tool rotational speed of 1,800 rpm in the present study. The glossy joint with equal thickness of base material can be attained, and the shoulder affected zone (SAZ) was obviously reduced. The results of transverse tensile test indicate that the tensile strength and elongation reach the maximum values of 248 MPa and 7.1% when the welding speed is 600 mm/min. The microhardness of weld nugget (WN) is lower than that of base material. The tensile fracture position locates at the heat affected zone (HAZ) of the advancing side (AS), where the microhardness is the minimum. The fracture surface morphology represents the typical ductile fracture.

Failure assessment diagram（ FAD） is usually used to evaluate the safety of welded structures containing cracks.There are three assessment levels in BS7910. As the assessment level increases,accuracy is improved and more data is required.This standard is widely used in safety assessment of pressure vessels and pipelines. The working level of offshore crane is relatively high and fatigue cracks can be found on it during the routine inspection. However,due to its high cost and long cycle of maintenance,the productivity is seriously affected. Therefore it is vital to commence safety evaluation on the cracked structure. This paper utilized Shao Yongbo’s experimental data to establish the 3C curves of the cracked structure of offshore crane,and compared it with the 2A curves of the BS7910 standard. The result shows that the tendencies of both curves are the same and 2A curve is more conservative. Thus the structure can be evaluated according to BS7910. This paper offers the critical load of T-plate that contains certain dimension of crack according to level 2A evaluation.

Taking the 2F2R macro micro manipulator as study object,its model is established by using the finite element method. Based on the cam curve theory,the equations of motion curve such as the acceleration,the 5 degree polynomial,the deformed trapezoid,the cycloid,the synthetic sine,and the deformed sine are derived in detail. Based on the above two aspects of works,the effect and rule of different motion curves on the elastic vibration of manipulator end are studied,which has a good reference value for the trajectory planning of this type of manipulator.

Accurate flatness measurement of silicon wafers is affected greatly by the gravity-induced deflection (GID) of the wafers, especially for large and thin wafers. The three-point-support method is a preferred method for the measurement, in which the GID uniquely determined by the positions of the supports could be calculated and subtracted. The accurate calculation of GID is affected by the initial stress of the wafer and the positioning errors of the supports. In this paper, a finite element model (FEM) including the effect of initial stress was developed to calculate GID. The influence of the initial stress of the wafer on GID calculation was investigated and verified by experiment. A systematic study of the effects of positioning errors of the support ball and the wafer on GID calculation was conducted. The results showed that the effect of the initial stress could not be neglected for ground wafers. The wafer positioning error and the circumferential error of the support were the most influential factors while the effect of the vertical positioning error was negligible in GID calculation.

Snakebites from Taiwan habus (Protobothrops mucrosquamatus) and green bamboo vipers (Viridovipera stejnegeri) account for two-thirds of all venomous snakebites in Taiwan. While there has been ongoing optimization of antivenin therapy, the proper management of superimposed bacterial wound infections is not well studied. In this Bacteriology of Infections in Taiwanese snake Envenomation (BITE) study, we investigated the prevalence of wound infection, bacteriology, and corresponding antibiotic usage in patients presenting with snakebites from these two snakes. We further developed a BITE score to evaluate the probability of wound infections and guide antibiotic usage in this patient population. All snakebite victims who presented to the emergency departments of seven training and research hospitals and received at least one vial of freeze-dried hemorrhagic antivenin between January 2001 and January 2017 were identified. Patient biodata, laboratory investigation results, and treatment modalities were retrieved. We developed our BITE score via univariate and multiple logistic regression analyses. The receiver operating characteristic (ROC) curve was plotted to evaluate the predictive performance of the BITE score. Out of 8,295,497 emergency department visits, 726 patients presented with snakebites from a Taiwan habu or a green bamboo viper. The wound infection rate was 22.45%, with seven positive wound cultures, including six polymicrobial infections. Morganella morganii, Enterococcus spp., Bacteroides fragilis, and Aeromonas hydrophila were most frequently cultured. There were no positive blood cultures. A total of 33.0% (n = 106) of snakebite patients who received prophylactic antibiotics nevertheless developed wound infections, while 44.8% (n = 73) of wound infection patients were satisfactorily treated with one of the following antibiotics: amoxicillin/clavulanic acid, oxacillin, cefazolin, and ampicillin/sulbactam. With the addition of gentamicin, the success of antibiotic therapy increased by up to 66.54%. The prognostic factors for the secondary bacterial infection of snakebites were white blood cell counts, the neutrophil lymphocyte ratio, and the need for hospital admission. The area under the ROC curve for the BITE score was 0.839. At the optimal cut-off point of 5, the BITE score had a 79.58% accuracy, 82.31% sensitivity, and 79.71% specificity when predicting infection in snakebite patients. Our BITE score may help with antibiotic stewardship by guiding appropriate antibiotic use in patients presenting with snakebites. It may also be employed in further studies into antibiotic prophylaxis in snakebite patients for the prevention of superimposed bacterial wound infections.

We report a novel T-XRD and Rietveld-refinement investigation of pyrolytic-graphite samples with high degree of graphene-layer-orientation and misfit-rotational-angle of ∼0.8° in the T-range from 12 K to 298 K. An anomalous variation of the graphitic c -axis which involves firstly negative-thermal-expansion (from 12 K to ∼50 K), a saturation-effect (from 50 K to ∼160 K) and then a positive expansion (from ∼180 K to 298 K) is evidenced. The reported trend is significantly different with respect to that expected by considering the standard-thermal-expansion α -parameter where no saturation-effect is present. SQUID-magnetometry revealed further presence of superconducting-like hysteresis which resemble those observed by Scheike et al.

Observation of ferromagnetic and granular superconductive features in highly-oriented-pyrolytic-graphite (HOPG) has recently attracted an important attention. We report a novel temperature dependent XRD and SQUID investigation of HOPG in the temperature range from 300.15 to 77.15 K. Unusual hysteresis features indicate the possible presence of vortex states in conditions of magnetic field approximately perpendicular to the HOPG layers. This interpretation is further supported by additional measurements performed on intermediate lamellae extracted by exfoliation. Evidence of a possible structural-transition in the c -axis of HOPG in the temperature range between 77 K and 100K is also provided by using the Rietveld refinement method. ZFC and FC measurements performed at high field values of 5000–10000 Oe, together with mFC-mZFC subtraction, highlight absence of a sharp depletion of the difference between magnetization signals towards zero. These observations may indicate the possible presence of additional unsaturated weak features, which are ascribed to superconductive signals as previously predicted by Scheike et al (Scheike et al 2013 Carbon ; 59 :140).

Objective: This article plans to investigate Fbxw8 protein expression in esophageal squamous cell carcinoma tissues. And its effect on the proliferation ability of esophageal squamous cancer KYSE70 cells is analyzed. Methods: We can detect Fbxw8 protein expression in esophageal squamous cell carcinoma tissues with IHC and analysis the expression with the sex, age, lymph node metastasis and tumor stage. We alsodetect the proliferation of KYSE70 cells with CCK 8. Result: Most esophageal squamous carcinoma tissues highly expressed Fbxw8 protein, and the expression was positively correlated with lymph node metastasis and tumor staging (P < 0.05). Fbxw8 siRNAs can significantly cut FBXW8 protein expression, while lowering the cell cycle related protein expression of Cyclin A, Cyclin B1, and inhibiting KYSE70 cell proliferation. Conclusion: Fbxw8 protein highly expressed in esophageal squamous carcinoma tissues, and closely related to tumor staging. Targeted inhibition Fbxw8 protein expression could significantly inhibit the proliferation of esophageal squamous carcinoma cells.

In view of the lack of coordination or guidance of green road concept and relevant evaluation to encourage sustainability, we redefined the concept of green road and its characteristics, and then reviewed some cross-sector targets of various departments related to green development. The history of green road related policies and studies were reviewed, and a green road evaluation indices system were established with 2 broad categories-compulsory and selective. The compulsory category contains 8 indices; and the selective category includes 76 indices, which are divided into 7 categories and 31 subcategories, covering design, construction and operation. In order to improve the evaluation continually, rating principles, grading methods and main reference literature were given. Then we selected 30 indices and design in a questionnaire to trial evaluation, and 11 projects of Hubei province were collected and used for analysis. Finally, based on the long-term and complexity of the evaluation system, we suggest some key improving strategies of green road evaluation in China. The establishment of the green road system is an attempt to bridge the requirements of different departments, and to stimulate the progressing technology to meet various challenges.

The government’s supervision of power grid enterprises will gradually focus on the transmission and distribution price, and the investment and income will be more strictly supervised. Under the new management requirements, the company must pay more attention to the compliance of the investment process, further strengthen the investment risk control, put an end to inefficient or invalid investment, strengthen the all-round and whole process supervision, and scientifically and accurately determine and carry out effective project cost control and management. It is the key to achieve project management objectives, and also an important measure of investment fine management and control. This paper takes historical cost data as the research object, constructs the whole process intelligent prediction and analysis model of power grid project cost, assists investment decision-making, reduces the balance rate, and improves the efficiency and efficiency of the company’s investment and lean management level.

With the rapid development of network technology, the electric power Internet of Things needs to face a large number of electronic texts and a large number of distributed data access and analysis requirements. If the system wants to complete accurate and efficient data analysis and build an existing data and service standard system covering the entire chain of energy and power business on the existing basis, it must implement massive electronic text retrieval, information extraction and classification in the power grid system. In order to achieve this purpose, a DNN neural network classification model is constructed to classify the text information of the power grid, and the effectiveness of the method is verified by experiments based on data from the substation information system.

Text classification is a common application in natural language processing. We proposed a multi-label text classification model based on ELMo and attention mechanism which help solve the problem for the sentiment classification task that there is no grammar or writing convention in power supply related text and the sentiment related information disperses in the text. Firstly, we use pre-trained word embedding vector to extract the feature of text from the Internet. Secondly, the analyzed deep information features are weighted according to the attention mechanism. Finally, an improved ELMo model in which we replace the LSTM module with GRU module is used to characterize the text and information is classified. The experimental results on Kaggle’s toxic comment classification data set show that the accuracy of sentiment classification is as high as 98%.

Masses of chlorine salts in the oceans engender a badly electrochemical erosion on the concrete since cross- sea bridge and harbor construction has been intensified in recent years, which has aroused a wide concern. This paper aims to study the corrosion mechanism of seawater chloride ion on the concrete with upper and lower two layers of intertidal zones set up according to different positions. A test is designed to make a comparative analysis on the resistance of marine biofilm to chloride permeability in two cases that the biofilm is active and inactive. The results show that chloride ion takes place electrochemical reaction and plays dual roles of anodic depolarization and conductivity. For its permeability to chloride ions, active biofilm shows stronger, which may be correlated to the halophilic bacteria contained in biofilm and the surface bonding effect of concrete. In relation to the upper intertidal zone, the resistance to chloride penetration in the lower layer of concrete is superior, which reveals that the lower biofilm has a better adhesion effect on the surface and plays a certain role in preventing the erosion of harmful substances.

This paper introduces a double-walled hollow pipe (DWHP) that demonstrates good corrosion resistance and mechanical properties and that can be used in pipeline transportation and structural stress components in marine, freshwater, and corrosive environments. We designed and machined the specimens to meet the bending bearing capacity using a cross section method. We conducted low-cycle loading tests of the specimens to investigate the energy dissipation capacity of the DWHP, the effects of different geometrical parameters, and the concrete-filled strength of the DWHP on energy dissipation capacity. The results show that the failure forms of the specimens are similar. The geometrical characteristics of the specimens, the cohesive function between the concrete and the steel plate, and the strength of the concrete-filled pipe showed a significant influence on the mechanical properties of the specimens. Hysteretic curves are plump and possess a high capacity for energy dissipation. The energy dissipation capacity of the specimen decreases with an increase in the slenderness ratio. The slope of strength degradation decreases with any increase in the strength of the concrete-filled pipe. We optimized the section design of the component by improving the constraint effect coefficient, and we effectively improved its stability by adding stiffeners to the inner side of the outer wall of steel.

The pitting corrosion of 304 L austenitic stainless steel joints with 308 L austenitic stainless steel as welding sticks was investigated in simulated concrete pore solutions with different chloride ion concentrations by potentiodynamic polarization curves, electrochemical impedance spectroscopy and Mott-Schottky curves. It is found that chloride ions play an important role in the corrosion behavior of the joints. When the chloride ion concentration increases, the corrosion potential, breakdown potential and charge transfer resistance of the joints at three different weld zones, i. e., base metal (BM), weld metal (WM) and heat affected zone (HAZ), in the simulated solutions decrease, but the charge carrier density and the number of pitting sites in the joints increase. In the same simu-lated solution, the weld metal shows a better corrosion resistance, followed by the heat affected zone, and the base metal has the lowest corrosion resistance due to its much lower charge transfer resistance and higher doping content.

According to impedance measurement method, a detection system of resonance frequency for magnetostrictive material based on AD5933 was designed. The hardware circuit and software design of the detection system were presented in details. The detection system uses impedance measurement module based on AD5933, microcontroller processing module based on MSP430F169, display module based on LCD 12864 and power supply module to realize data collection, processing, storage of resonance frequency of magnetostrictive material and impedance spectrum display. The test results show that the detection system has characteristics of low measurement error, strong anti-interference and high real-time performance, and average detection error is as low as 7 Hz.

A new cementing agent, RSGC, designed for filling was prepared with red mud, blast furnace slag, flue gas desulphurization gypsum and a little cement clinker. The adaptability of RSGC used in different mines was studied and the early hydration including microstructure and structural changes of silicates and aluminates were investigated by scanning electron microscopy and nuclear magnetic resonance techniques. It is found that RSGC applies not only to iron ore mines but also to copper mines, gold mines and lead——zinc mines which generally adopt the filling mining method. Filling materials used RSGC exhibit significant strength and water retention advantages over traditional cement filling materials. The RSGC paste hardens at 2.5 h. Ettringite generated before 2.5 h makes important contributions to the setting and hardening. After 4 h, parts of the tetrahedrally-coordinated aluminium turn into an octahedrally-coordinated state, and polymerization of silicates increases. This phenomenon means that ettringite, C——S——H gels and zeolites generate continuously. The combination of these hydration products in various sizes and shapes forms a compact arrangement and a dense structure, which is probably the reason why the RSGC paste obtains strength from 4 h and the strength increases dramatically from that time.

Hydration reactions of samples made from skarn-type copper tailings, blast furnace slag, quartz sand, cement clinker and natural gypsum during the process of pre-curing, autoclaving and re-curing were investigated by strength testing, X-ray diffraction analysis and scanning electron microscopy. The influences of calcium and silicon contents on the amount and variety of hydration products generated in the reactions were analyzed and the effects of hydration products on the strength of the samples were discussed. It is found that the strength of autoclaved products in different curing stages depends on the amount and variety of hydration products generated in the curing process, while the amount and variety of them hinge on the amount and existence form of calcium and silicon.

On the purpose of improving the utilization level of mine solid wastes and reducing the cost of backfill mining, this article reports an experimental study on preparing cementitious materials for backfilling by using water-granulated nickel slag. Mechanical and chemical activation methods were adopted to improve the cementitious activity of the slag. Taking the strength of backfill bodies as evaluation standards, the hydration activity and cementitious performance of the slag were investigated by changing the grinding fineness and activated agents, and the chemical activation mechanism was analyzed. The results indicate that the cementing agent prepared from the slag (occupying 85% of the total raw materials) can be used to replace cement and meet the production requirements of back-filling materials.

The purpose of this study is to confirm the effect of ambient temperature, airspeed, and wind direction on the heat transfer around the human body. A fixed surface temperature (33 °C) thermal manikin (TM) with 16 segments was employed. First, the manikin was placed in a climate chamber with ambient temperatures of 20 °C, 24 °C, and 28 °C, at airspeeds of less than 0.1 m/s to represent calm condition. Higher ambient temperatures led to a decrease in the convective heat transfer coefficient. The convective heat transfer coefficients for the sitting posture were higher than those of the standing posture. The same TM was then put in a wind tunnel with airspeeds ranging from 0.25 m/s to 1.4 m/s to represent forced convection. The TM was set to face upwind, downwind, and perpendicular to the wind (i.e., its right side facing the wind). Regression models for the convective heat transfer coefficient and airspeed for different wind directions and postures were derived. In contrast to the calm condition, the convective heat transfer coefficients for the sitting posture were lower than those for the standing posture. The convective heat transfer coefficients for the standing posture were largest when the TM was facing downwind, and smallest when the right side of the TM was facing the wind. To verify the results of the experiment, computational fluid dynamics (CFD) analysis was performed with conditions matching those of the experiment by using a computational TM with the same shape as that used in the experiment. The boundary conditions of the CFD analysis were set from the experiment. The CFD analysis results were consistent with the experimental data.

Whether or not the tight oil in the Triassic Yanchang Formation of the Ordos Basin is controlled by structural factors is a controversial issue, the relationship between the structural factors of the strata and the distribution of tight oil is limited to the study of current structures. The traditional view is that structural factors have no obvious control over the formation and distribution of the oil reservoir. Taking the Chang 8 member of the Triassic Yanchang Formation in the Ordos Basin as an example, this paper studies respectively the burial of strata-hydrocarbon generation history of the individual well and the structural evolution history of strata in the basin by using software tools of the Genex burial-hydrocarbon generation history restoration and TemisFlow evolution of stratigraphic structures. It is considered that the hydrocarbon generation period of the source rock of the Triassic Yanchang Formation in the Ordos Basin is from early Middle Jurassic to end of Early Cretaceous. By reconstructing the evolution and structure of the Chang 8 member during the hydrocarbon accumulation period, combined with a comprehensive analysis on the distributional characteristics of the Chang 8 oil reservoir, we found the palaeoslopes and palaeohighs of the Chang 8 reservoir to represent areas in which tight oils were distributed. Palaeo-structural characteristics of the target layer exhibit control over the Chang 8 reservoir. The new theory underlying tight oil exploration, which is based on the recovery of the palaeogeomorphology of the target layer during the hydrocarbon generation period, incorporates the vital roles of key controlling factors over tight oil accumulation, so that the mind-set on tight oil exploration in the Ordos Basin has evolved.

This paper puts forward a short-baseline dual-antenna BDS/MIMU integrated navigation, constructs the carrier phase double difference model of BDS (BeiDou Navigation Satellite System), and presents a 2-position initial orientation method on BDS. The Extended Kalman-filter has been applied for the integrated navigation system. The differences between MIMU and BDS position, velocity and carrier phase information are used as measurements. The experiment results indicate that the position error is less than 1m, the pitch angle error and roll angle error are less than 0.1°, and the heading angle error is about 1°. It shows that the new integrated navigation system has good performance and can be applied in various fields including USV and UAV.