滑翔增程弹导航系统误差修正方法研究

为了提高滑翔增程制导炮弹的姿态测量精度,分析了单GPS天线测量弹体姿态角的计算方法,应用GPS和INS全组合的方式,采用INS和GPS的位置、速度和姿态误差信息作为观测量,设计了卡尔曼滤波器,将滤波估计的结果反馈给INS,实现对测量系统全参数的误差修正.数值计算和仿真结果表明,采用基于GPS姿态测量信息的Kalman滤波方法,对INS惯导系统测量误差进行修正,降低了3个姿态角的测量误差,加快了系统误差收敛速度,提高了滑翔控制系统的控制精度,增加了制导炮弹滑翔增程的效果.     

一种鱼雷俯仰角出现±900°时的姿态仿真方法

摘要：随着鱼雷发射平台的多样化,火箭助飞鱼雷、空投鱼雷、自导水雷以及高空反潜鱼雷在发射和运动过程中会出现俯仰角在±900°附近的情况。当鱼雷俯仰角为±900°时,立式三轴转台的内环轴与外环轴重合,无法提供3个自由度的运动,致使鱼雷姿态仿真无法进行。通过改变敏感元件安装方式,建立在该种安装方式下三轴转台的驱动方程以及转台转角与鱼雷姿态角的转换表达式,解决了鱼雷俯仰角出现±±900°时的姿态仿真。数学仿真和半实物仿真结果表明,该方法正确可行,适用于鱼雷垂直发射、垂直入水以及俯仰角出现±900°时的半实物仿真试验。     

基于二维表格法的课程目标设置——以绿色可持续建筑教学的认知层面为例

随着绿色建筑设计教学改革的深入开展,在关注于将绿色建筑类课程融入到现有教学体系的过程中,相应的教学内容的选择以及课程设置成为了教学改革的主要内容之一。通过建筑教学方式与教育学原理的结合,以绿色建筑设计的认知层面为例展开讨论,以列出行为目标与行为方式的手段形成具体的教育目标,并按照据此构成的二维表格选择各教学层面的具体教学目标,以期通过教育目标的二维表格形式来指导绿色可持续类课程设置以及教学内容的选择,为未来绿色建筑教学改革提供参考。     

The attitudes of French and Spanish winegrowers towards the use of cover crops in vineyards

Vineyards are an intensive cultivation system and expose the soil to long-lasting stress. Many vineyard areas already show high degrees of soil degradation. To prevent further soil erosion, cover crops, which have various positive effects on the environment, are highly recommended. But, depending on the climatic conditions, cover crops can reduce grape yields and are sometimes more work intensive than bare soil management. In some areas cover crops are already widespread while in others bare soil is dominant. In this qualitative study, we explore the attitudes of European winegrowers towards cover crops and determine the background for differences in the adoption of greened vineyards. Thus, we conducted focus groups with winegrowers in two different regions, namely Coteaux du Layon in France and Montilla-Moriles in Spain. In this setting, the transregional differences are mainly based on the climatic conditions but also on different business structures and knowledge levels. Direct sellers seem to be more attentive to the environment and use cover crops more often than farmers which sell their grapes to cooperatives.     

基于相机的转台稳定性检测方法研究

高精密转台常用于高精度测量仪器的性能测试,或作为激光扫描仪的稳定平台使用,而转台的稳定性直接影响仪器的测量精度.提出一种利用数码相机对转台稳定性进行标定的方法,在转台运动时,安装在转台上的相机连续获取相片,基于摄影测量原理,计算相机的空间位置和姿态,从而确定转台的运动轨迹.实验结果表明,该方法可以有效地检测转台运动的稳定性.     

地面出入式盾构法隧道施工技术研究综述

地面出入式盾构(GPST)由日本株式会社大林组研发,作为一种新型盾构隧道施工方法,无需传统盾构的端头工作井,明显减小对周围环境的影响,同时缩短工期。该技术目前的实践工程较少,存在多方面工程技术难题。根据已有研究资料,阐述地面出入式盾构的相关技术难题,主要从隧道衬砌、盾构姿态、同步注浆等几个方面进行总结,分析现有研究不足之处,提出需要进一步研究的方向和研究思路。     

Cooperation in the evolutionary iterated prisoner’s dilemma game with risk attitude adaptation

The Iterated Prisoner’s Dilemma (IPD) game has been commonly used to investigate the cooperation among competitors. However, most previous studies on the IPD focused solely on maximizing players’ average payoffs without considering their risk preferences. By introducing the concept of income stream risk into the IPD game, this paper presents a novel evolutionary IPD model with agents seeking to balance between average payoffs and risks with respect to their own risk attitudes. We build a new IPD model of multiple agents, in which agents interact with one another in the pair-wise IPD game while adapting their risk attitudes according to their received payoffs. Agents become more risk averse after their payoffs exceed their aspirations, or become more risk seeking after their payoffs fall short of their aspirations. The aspiration levels of agents are determined based on their historical self-payoff information or the payoff information of the agent population. Simulations are conducted to investigate the emergence of cooperation under these two comparison methods. Results indicate that agents can sustain a highly cooperative equilibrium when they consider only their own historical payoffs as aspirations (called historical comparison) in adjusting their risk attitudes. This holds true even for the IPD with a short game encounter, for which cooperation was previously demonstrated difficult. However, when agents evaluate their payoffs in comparison with the population average payoff (called social comparison), those agents with payoffs below the population average tend to be dissatisfied with the game outcomes. This dissatisfaction will induce more risk-seeking behavior of agents in the IPD game, which will constitute a strong deterrent to the emergence of mutual cooperation in the population.     

Using travel socialization and underlying motivations to better understand motorcycle usage in Taiwan

This study introduces self-determination theory (SDT) to refine previous models of vehicle usage motivation. We add travel socialization theory regarding parental influence on vehicle usage to enhance previous structural models describing motorcycle usage behavior. Our newly developed model was empirically verified in a sample of 721 motorcycle users in Taiwan. In addition to instrumental, symbolic, and affective motivations, perceived parental attitudes (PPAs) towards motorcycle riding were found to have a significant effect on individuals’ motorcycle use habits. Additionally, participants who perceived their parents to have more positive attitudes toward motorcycles were found to have more experience being chauffeured on motorcycles by their parents. Based on these results, we suggest means to confront the challenges brought on by the rapid growth of motorcycle usage, especially serious motorcycle traffic accidents. These results improve our understanding motorcycle usage in Taiwan and can be used by transportation professionals who are seeking solutions to the rapid growth of motorcycle usage.     

Epos – an instrument for the assessment of the ethical position in software development

Digital technology becomes more powerful, intelligent, pervasive and ubiquitous. Ethical aspects of this development have not yet drawn the appropriate attention of researchers and engineers. This paper presents an instrument that aims at measuring the individual ethical position with regard to the design and development of computer software. The development of the Epos tool was based on two data collections. The data of the first survey (n₁ = 147 participants) were used to select items and to determine the factorial structure of the questionnaire. Results show that the Epos instrument reliably assesses peoples’ ethical opinion with respect to five central components: (1) regulation, (2) data privacy, (3) domain specific knowledge, (4) societal responsibility and (5) company responsibility. In the second survey, we determined the stability of the instruments factor structure by assessing a sample of n₂?=?196 participants. A confirmatory factor analysis (CFA) supported the initial factor structure. Next steps and further implications are discussed regarding the final version of the questionnaire.     

A machine-vision inspection system for conveying attitudes of columnar objects in packing processes

This paper is a new study on developing a machine vision system for inspecting the conveying attitudes of columnar objects. The presented system consists of image pre-processing, feature extraction, and attitude diagnosis. First of all, in order to segment the objects from the background (namely image pre-processing), an improved maximum between-class variance method is proposed for searching a histogram peak and calculating a threshold value based on the statistics and probability, to solve the problems caused by the non-uniform brightness in a realistic conveyor belt. Then, an open morphological operation is used to eliminate the noise from the binary images produced in the pre-processing step. In the second step (feature extraction), the features of columnar objects are determined by four methods, edge line detecting method, intercepting method, rectangle locating method and feature statistic method. Finally, the diagnosis for the conveying attitudes of columnar objects is based on a hybrid classifier using random forests, and a fuzzy logic. The proposed system is applied to a realistic process for packing industrial explosives. The results of experiments show that the proposed system allows efficient and accurate 100% inspection for the conveying attitude, which ensures the high speed and steady operation of a packing line.