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On a narrow warship platform, the coordinated use of shipborne weapon systems may cause firepower conflicts, which seriously endangers the ship safety. Meanwhile, with directed-energy weapons mounted on ships, firepower conflicts between weapons become a “high probability event”. Aiming at the problem of firepower safety control, based on the research about the collision probability model of air crafts and space targets and according to the cone of fire model of conventional weapons and directed-energy weapons, this paper solved the firepower conflict probabilities between conventional weapons as well as between conventional weapons and directed-energy weapons respectively using the methods of probability theory, and established the firepower safety control model. Then the calculation of firepower conflict probability was carried out using the dimensionality reduction method based on the equivalent conversion of polar coordinates and the power series method based on Laplace transform. The simulation results revealed that the proposed model and calculation methods are effective and reliable, which can provide theoretical basis and technical support for resolution of firepower conflicts between weapons.

Effective prediction of atmosphere pollutant concentration is an essential and vital activity, for the benefit of conducting preventive measures to protect public health in advance. This significant activity has attracted extensive researches, of which the majority focus on addressing the prediction of specific value in the time series. Considering the imprecision of point prediction caused by the violent fluctuation in pollutant concentration, and the fact that the precise value is not as good as the degree of pollution adaptable for human perception and decision-making, a novel multifactor fuzzy time series (FTS) forecasting model for air quality level forecast is proposed in this paper. In this model, the fuzzy derivation mechanism of conventional FTS model is implemented by support vector machine (SVM), which enhances the systematization of the FTS model and overcomes its disability in simultaneously considering other influencing factors. Besides, to further improve the accuracy of our model, random forest (RF) and fuzzy information granulation (FIG) are employed to construct the optimal combination of influential variables. Finally, to verify the effectiveness of the proposed model, a case study and three kinds of contrastive models are performed, so as to further highlight the superior performance of the proposed model.

This study was to investigate the inotropic effect of atractylodin and its underlying mechanism. The cardiac pressure-volume loop (P-V loop), Langendroff-perfused isolated rat heart, patch-clamp, Ca2+ transient and western blot techniques were used. The results demonstrated that atractylodin (3 mg/kg, ip) remarkably increased the left ventricular stroke work, cardiac output, stroke volume, heart rate, ejection fraction, end-systolic pressure, peak rates of rise and fall of left ventricular pressures (+dP/dtmax , -dP/dtmax ), the slopes of end-systolic pressure-volume relationship (also named as end-systolic elastance, Ees) and reducing end-systolic volume and end-diastolic volume in the in vivo rat study. Also, atractylodin (3 mg/kg, ip) significantly decreased diastolic blood pressure and the arterial elastance (Ea) without significant systolic blood pressure change. In addition, atractylodin (0.1, 1, 10 µmol/L) also increased the isolated rat heart left ventricular developed pressure which is the difference between the systolic and diastolic pressure in non-pacing and pacing modes. Furthermore, JMV-2959 (1 μmol/L), a ghrelin receptor unbiased antagonist, blocked the increased left ventricular developed pressure of atractylodin in isolated rat hearts. Finally, atractylodin (5 µmol/L) increased the amplitude of Ca2+ transient by enhancing SERCA2a activity, the sarcoplasmic reticulum Ca2+ content and the phosphorylation of phospholamban at 16-serine. These results demonstrated that atractylodin had a positive inotropic effect by enhancing SERCA2a activity which might be mediated by acting ghrelin receptor in myocardium. In conclusion, atractylodin which had the positive inotropic effect and decreased diastolic blood pressure might serve as an agent for the treatment of heart failure in clinical settings.

In order to meet the operational requirements of modern naval warfare, naval ships are equipped with growing types and quantities of weapons, but their overall combat effectiveness has not increased correspondingly. The reason is that different shipborne weapon systems have overlapping fields of fire on the relatively narrow ship platform, thus interfering with each other, which seriously endangers the ship safety. Therefore, it is critical to solve the major problem of firepower compatibility, namely, how to turn from increasing the firepower density of shipborne weapons to improving the strike-defense capabilities of the ship. Firepower compatibility is an important technology to give full play to the overall combat effectiveness of the weapon systems in the complex environment of the ship platform under the principle of ensuring the ship and crew safety. This paper summarizes the theoretical basis of the firepower compatibility technology of operations research, including the design of the intrinsic field of fire, fixed safety field of fire and active safety field of fire, and collates information about the development of the firepower compatibility technology for conventional weapons, such as firepower compatibility between conventional weapons and ship deck facilities, and firepower compatibility between conventional weapons. The firepower compatibility technology for conventional weapons contains four methods: firepower compatibility priority analysis, firepower conflict judgment for the satefty distance of vertically fired weapons, firepower conflict judgment for the safety distance of inclined revolving weapons and airspace resources occupation. The advantages and disadvantages of the above four operations research methods are compared and analyzed to obtain their commonalities and key points for improvement. In terms of the differences between the directed-energy weapons and conventional weapons, this paper introduces the technical characteristics and advantages of directed-energy weapons and compares the possible solutions to firepower compatibility of the two catagories of weapons. Then the key firepower compatibility technologies for directed-energy weapons are discussed and analyzed from three aspects: the construction of the cone of fire, firepower conflict judgment and dynamic firepower compatibility control. Finally, the paper points out the key and difficult problems in the firepower compatibility technology for directed-energy weapons, gives where research breakthroughs can be made in this area, and maps out the next development plan for this technology.

This study aimed to explore the positive inotropic effect of phosphodiesterase type 9 (PDE9) inhibitor PF-04449613 in ratsand its cellular and molecular mechanisms. The heart pressure-volume loop (P-V loop) analysis was used to detect the effects of PF-04449613 on rat left ventricular pressure-volume relationship, aortic pressures and peripheral vessel resistance in healthy rats. The Langendorff perfusion of isolated rat heart was used to explore the effects of PF-04449613 on heart contractility. The cardiomyocyte sarcoplasmic reticulum (SR) Ca

Booming technological advances and turbulent military reforms have promoted the continuous advancement of weapons and equipment. High-power microwave (HPM) weapons have changed the damage modes of traditional guns, missiles and other kinetic energy weapons, as well as having the huge advantage of "changing the rules of the game." The study of exterior ballistics of high-power microwave weapons has theoretical support for the design and development of weapons and the verification of performance indicators, and is also an important basis in the firing application of high-power microwave weapons. By studying the coupling mechanism between HPM weapons and targets, an exterior ballistics description of HPM weapons is given According to the description of exterior ballistics, the differences between HPM and traditional weapons in definitions, accuracies, space trajectories, space descriptions and "end points" are summarized and the exterior ballistics space transmission is established. This study reveals the nine major transmission laws of the exterior ballistics of HPM weapons. The constructed model and related theories of the transmission laws for exterior ballistics lay a theoretical foundation for the in-depth study of key technologies of HPM weapons, such as fire control and damage assessment.

This study investigated the hemodynamic effect of Bay 60-7550, a phosphodiesterase type 2 (PDE2) inhibitor, in healthy rat hearts both in vivo and ex vivo and its underlying mechanisms. In vivo rat left ventricular pressure-volume loop, Langendorff isolated rat heart, Ca2+ transient of left ventricular myocyte and Western blot experiments were used in this study. The results demonstrated that Bay 60-7550 (1.5 mg/kg, i. p.) increased the in vivo rat heart contractility by enhancing stroke work, cardiac output, stroke volume, end-diastolic volume, heart rate, and ejection fraction. The simultaneous aortic pressure recording indicated that the systolic blood pressure was increased and diastolic blood pressure was decreased by Bay 60-7550. Also, the arterial elastance which is proportional to the peripheral vessel resistance was significantly decreased. Bay 60-7550 (0.001, 0.01, 0.1, 1 μmol/l) also enhanced the left ventricular development pressure in non-paced and paced modes with a decrease of heart rate in non-paced model. Bay 60-7550 (1 μmol/l) increased SERCA2a activity and SR Ca2+ content and reduced SR Ca2+ leak rate. Furthermore, Bay 60-7550 (0.1 μmol/l) increased the phosphorylation of phospholamban at 16-serine without significantly changing the phosphorylation levels of phospholamban at 17-threonine and RyR2. Bay 60-7550 increased the rat heart contractility and reduced peripheral arterial resistance may be mediated by increasing the phosphorylation of phospholamban and dilating peripheral vessels. PDE2 inhibitors which result in a positive inotropic effect and a decrease in peripheral resistance might serve as a target for developing agents for the treatment of heart failure in clinical settings.

A method to reconstruct the acoustic far-field using a semi-circular sensor array is proposed. Firstly, the pressures in the acoustic far-field are measured by a semi-circular sensor array; then, the acoustic far-field is reconstructed based on the theory of acoustic radiation modes. The numerical simulations for reconstructing the acoustic far-field of a baffled rectangular plate are conducted. The results show that the acoustic far-field of the baffled rectangular plate can be reconstructed accurately by a few sensors on the semi-circular array. The influence of noise to the reconstruction of acoustic field is analyzed, and the robustness of the proposed method is proved. This paper provides a method for the reconstruction of acoustic far-field through a simple measuring array. The method can be applied to the acoustic field reconstruction of large structures, and has good engineering application prospects.

Precise short-term atmospheric pollutant concentration forecasting is significant for providing early warning information against harmful pollutants. Many studies on pollutant concentration prediction have proven the excellence of decomposition and ensemble models. However, in most of those studies, the training and test sets are divided based on the decomposition results rather than the original time series. In such decomposition and ensemble framework, future information is used for prediction, which is impractical. Furthermore, a significant boundary effect in the decomposition results is also a serious problem. Thus, this study develops an adaptive forecasting scheme aiming at ensuring the model practicality and adapting to the boundary effect. This study also introduces independent component analysis (ICA) to help extract the hidden information of the original series and improves the ability to screen influential variables. Finally, an adaptive decomposition and ensemble model combined with ICA is developed. Using data collected from Beijing Shunyi station, a case study and two comparative experiments are conducted, through which the contribution of the methods used in the proposed model and the superior performance of the model are demonstrated.

In this paper, we investigate the main characteristics of oblique water entry of high-speed cylindrical projectiles, which involves multiphase flows due to cavitation. Numerical simulations are performed by solving Reynolds-averaged Navier–Stokes (RANS) equations coupled with 6-degree of freedom (DOF) rigid-body motion equations. The model is validated firstly by comparing with previous results. Then the studies of different entry conditions are performed, and we find that the velocity attenuation during the entry process is mainly affected by the projectile geometric parameters such as its head shape and length, rather than the entry angles and velocities. The drag coefficient is also dominated by the head shape. Furthermore, the time of surface closure of cavity is linear with the entry velocity of the projectile.

This letter develops a novel, ultracompact, insulated, and refined fiber-optic device that is based on a pair of tapered fiber plugs that are bridged in a tiny section of a hollow-core fiber (HCF). The proposed fiber plugs are fabricated by a single-mode fiber taper and are inserted into the HCF. Two taper plugs are bridged with each other inside the section of HCF by fusion splicing. The two ends of the HCF are fused to close the hollow core and form a rigid structure. When the fabricated sensor is utilized to sense acoustic vibrations, the tiny vibration sensing element is insulated and protected against the robust HCF, so it not easily damaged or polluted. The experimental results demonstrated favorable responses to vibrations.

In order to explore the method of collaborative decision of command and control, first of all, the relationship between chaotic decision and collaborative decision is compared, the complexity and chaos of the system of collaborative decision is discussed from the theoretical level, on this basis, chaos characteristics of decision system is described bytheorem.

Based on the theory of information and structure entropy, this paper analyses the influence of collaborative command and control system on information flow. Two concepts, time-effect and equality of information flow, are introduced, and the time-effect quality model is established, which can be used for evaluating the order degree of collaborative command and control system. Centralized, recursive and network cooperative structure and its time and space complexity respectively discussed. Study has shown that the recursive cooperative structure under the control of the command center is a relatively good structure.

Pot experiment was conducted with the cutting seedlings of Ilex kudingcha C. J. Tseng. By adding lead, copper solution and self-exist zinc in soil, we conducted the research for the phytoavailability of heavy metal in the different soil situation. The characterization methods of the phytoavailability were investigated. Results show that lead, copper and zinc are the strong absorption elements from BAC (Biological Absorption Coefficient) averages of 13 groups experiment. The order of BAC averages is lead > copper > zinc. 0.05mol/L EDTA-2Na can be used as the extracting agent of lead or copper, 0.1mol/L HCl can be used as the extracting agent of zinc. They can be used for the characterization methods about the phytoavailability of lead, copper, zinc in soil by the single extraction method. 0.1mol/L HC1 is adopted to extract soil, and weighted ion impulse of the lead, copper, zinc in the extraction fluid is calculated, which can well simultaneously characterize the phytoavailability of heavy metal lead, copper, zinc in kudingcha soil.

Based on the field investigation and sampling, seven dominant wild plants and relative soil samples in Hainan Shilu iron mines area were collected. To analyze and study the contents of heavy metals Pb, Cd, Cu, Fe, Mn and Zn in these samples and the characteristics of enriching heavy metals of these dominant plants. Results of this study showed that the contents of the same heavy metal in the soils around roots system of seven dominant plants had a large range of variation, to a certain extent, it reflected the difference of the enriched characteristics of different plants to the same heavy metal. All seven dominant plants had endurance and enriched characteristics to Fe. Bothriochloa root hoarded up abundant Fe, Cu, Zn and its stored characteristics to Mn, Pb, Cd also stood out from the seven dominant plants, so it could be used as good plant which absorbed a large amount of heavy metals but mainly held in the roots, this result had a good consistance with the finding that the enriched and transferred characteristics of Bothriochloa to heavy metals in soil. In the soil of low cadmium pollution, Calopo and Bothriochloa had higher concentration factors of cadmium, this indicated they had a good potential in high cadmium pollution soil. White tephrosia and Cyperus alternifolius had the higher metastasis ability to Mn, Zn, Cd, which had the potential of phytoremediation.