无人机飞行训练资源配置效率的AHP-Arena综合评价方法

为降低传统层次分析法(analytic hierarchy process,AHP)赋权过程主观片面性影响,提出了一种综合AHP与Arena仿真建模技术的无人机训练资源配置效率评价方法。基于飞行训练流程分析,确定了训练资源配置效率影响因素和效率评价指标,建立了层次型综合评价体系,概括了AHP-Arena综合评价步骤。利用Arena建模软件构建训练流程动态仿真系统并验证有效性,采用单变量数值仿真法、均方差决策法完成了影响因素客观赋权,通过线性加权综合法得出综合评价系数,实现资源配置效率评价与方案优选。实例应用说明了该方法的有效性,同时,该方法可推广至其他类似的训练过程中,亦可为其他多因素、多指标评价决策过程提供借鉴。     

浅谈变声期声乐教学的要求与方法

对于许多高等院校的音乐教育专业来说,培养目标的主要在于培养合格的中小学音乐教师。而这对于即将成为音乐教师的学生来说,如何掌握青少年变声期前后的声音特征,心理特征;并能运用科学的方法,适当的要求来进行教学,具有非常重要的意义。     

Rigid elliptical cross-section ogive-nose projectiles penetration into concrete targets

The elliptical cross-section ogive-nose projectile (ECOP) has recently attracted attention because it is well suited to the flattened shape of earth-penetrating weapons. However, the penetration performance of ECOPs has not been completely understood. The objective of this study was to investigate the pene-tration performance of ECOPs into concrete targets using a theoretical method. A general geometric model of ECOPs was introduced, and closed-form penetration equations were derived according to the dynamic cavity-expansion theory. The model was validated by comparing the predicted penetration depths with test data, and the maximum deviation was 15.8％. The increment in the penetration depth of the ECOP was evaluated using the proposed model, and the effect of the major—minor axis ratio on the increment was examined. Additionally, the mechanism of the penetration-depth increment was inves-tigated with respect to the caliber radius head, axial stress, and resistance.     

Supercritical carbon dioxide as a new working medium for pneumatic launch: A theoretical study

Compared with the conventionally gaseous or liquid working media, the specific internal energy of supercritical carbon dioxide (SCD) is higher at the same temperature and pressure, and the critical temperature of carbon dioxide is close to room temperature, making SCD a potential new working medium for pneumatic launch. To analyze the feasibility of this conception, an analytical model of a pneumatic catapult is established on basis of the conservations of mass and energy. The model consists of a high-pressure chamber and a low-pressure chamber connected by multiple valves, and there is a movable piston in the low-pressure chamber that can push an aircraft to accelerate. The effects of the launch readiness state of SCD in the high-pressure chamber, the initial volume of the low-pressure chamber and the valve control on the movement of the aircraft are analyzed. It is found that there is a restrictive relation between the temperature and pressure of the launch readiness state of SCD, i.e., there is a maximum allowable launch readiness pressure when the launch readiness temperature is fixed. If this restrictive relation is not satisfied, the working medium in the low-pressure chamber will drop to its triple point within a few milliseconds, leading to a launch failure. Owing to this restrictive relation, there is an optimal launch readiness state of SCD with the highest working capacity for any allowable launch readiness temperature. The pressure of the low-pressure chamber will decrease significantly as the initial volume increases, leading to a decreased acceleration of the aircraft. The ac-celeration can be controlled below a critical value by a designed sequential blasting technique of multiple valves. The calculated results show that a 500 kg aircraft can be accelerated from 0 to 58 m/s in 0.9 s with 36 kg of carbon dioxide. This research provides a new technique for the controllable cold launch of an aircraft.     

Reluctant guerrillas in early nineteenth century China: the White Lotus insurgents and their suppressors

ABSTRACT

At the turn of the nineteenth century, China’s Qing dynasty (1644–1912) was hit by a sectarian rebellion. Commonly considered a breakpoint marking the end of the dynasty’s golden age spanning most of the eighteenth century, the war to suppress the rebels, referred to as the White Lotus War (1796–1804) in this article (‘White Lotus’ was the umbrella name used by both the authorities and some sectarians for their teaching), exposed many structural drawbacks of the Qing political and military systems and depleted the dynasty’s financial resources, which had never been recovered. Reluctant in embracing guerrilla warfare in the beginning, the insurgents quickly turned themselves into master guerrillas. Shuttling in two massive mountain ranges in central China, they managed to prolong their rebellion and fought some successful battles against their suppressors. Superior in manpower, weaponry, and logistical support, the government forces had to adapt to guerrilla warfare, albeit passively and ineptly. This article gives a brief introduction to this little-known episode of guerrilla war at the turn of the nineteenth century in Qing China, expounds the strengths and weaknesses of both sides, and sheds light on the roots of the war’s long duration and the grim consequences to the Qing state.     

网络舆论智能引导仿真推演模型与系统构建

传统马甲机械发帖的网络舆论引导方式存在智能水平不高、效果不佳的缺点。人工智能的快速发展为网络舆论智能引导奠定了坚实的理论与技术基础。本文突破新闻传播学的思维定式，利用智能体、系统建模与仿真等理论技术，研究网络舆论智能引导，提出“态势感知-仿真推演-舆论引导”的网络舆论智能引导思路，构建网络舆论智能引导仿真推演模型，明确仿真推演工具，进而构建网络舆论智能引导系统，在仿真推演的基础上实施网络舆论引导，从而颠覆传统马甲的机械式发帖引导方式，破解难以在真实网络环境中直接尝试各种引导策略的困局。本文的研究成果对于丰富网络舆论斗争理论，占领网络舆论制高点，具有重要理论意义和参考价值。