三相异步电动机Y-△降压起动的PLC控制线路设计

针对三相交流异步电动机在额定电压下直接起动时存在的弊端,通过PLC中的定时器及互锁、连锁等保护手段对电动机Y-△降压起动加以控制,从而避免操作不当或误操作而引起事故。这里主要讨论改进后的继电器接触控制电气原理图,对应的I/O配置接线图,PLC梯形图,部分程序,并对改进后的原理进行分析,从而得出采用PLC控制的Y-△降压起动的优越性。     

浅谈高校交往空间设计

文章首先对我国高校交往空间的基本状况做了简要的介绍,探讨了从空间形态的整体性、多样性、可生长性等方面塑造高等学校交往空间的可能性。     

Bringing together acculturation theory and intergroup contact theory: Predictors of Flemings’ expectations of Turks’ acculturation behavior

The present paper explores Flemish majority members’ expectations concerning the acculturation of Turkish minorities. We studied two kinds of antecedents: majority members’ perceptions of Turkish minorities’ acculturation behavior and their experiences of intergroup contact. The possible mediating role of outgroup affect was also investigated. 247 Flemish high school students completed a survey. Data were analyzed using path analyses. Results show that positive contact experiences and perceiving that Turkish immigrants make efforts to engage in contact with the host group and/or to adopt the host culture are associated with less negative affective reactions towards Turkish migrants. Perceiving that Turkish immigrants maintain their heritage culture is associated with more negative affective reactions. Our results further revealed that increased negative affective reactions are associated with less support for culture maintenance and for contact with the host group but with a higher demand for host culture adoption. The present results also show that expectations of contact engagement and expectations of host culture adoption cannot be considered as equivalent. This implies that results from studies using Berry's conceptualization of acculturation expectations (Berry, 2001) and results from studies using Bourhis’ conceptualization of acculturation expectations (Bourhis, Moïse, Perreault, & Senécal, 1997) are not directly comparable. Our data also clearly disconfirm the orthogonal structure of the fourfold acculturation model for majority members’ acculturation expectations, suggesting that relying on the specific dimensions defining acculturation expectations may constitute a more valid approach to understand ongoing acculturation processes.     

高速铁路运营过程中的关键问题：轮轨磨耗等

随着高速铁路运营里程和列车运营速度的不断增长,出现了一些和列车轨道耦合大系统密切相关的关键科学和技术问题。这些问题不仅影响到列车的运行品质,甚至威胁到安全运行,是当前高速铁路运用和发展中急需解决的问题。本文系统描述了高速铁路在运营过程中所出现的一些关键科学和技术问题,并述评了全世界有关这些问题的研究进展、现状和不足之处,提出了今后有利于认识和解决这些问题的发展方向。在长期高速运营的铁路大系统环境中,这些问题的形成的机理、发生、发展过程和预防措施的研究,需要从列车／轨道耦合大系统运营环境（速度、路况、气候和运用维修）、系统的自身参数匹配、材料选用和运营成本等全面系统考虑,并从理论、技术、工艺、监控和维修等方面解决。     

Exploring the Relations between In-service Training,Prior Contacts and Teachers’ Attitudes towards Persons with Intellectual Disability

This study investigates the relations between teachers’ attitudes towards persons with intellectual disability (ID), in-service training on ID, and prior contacts with persons with ID. A sample of Canadian elementary school teachers (N?=?118) completed the Attitudes Toward Intellectual Disability Questionnaire, which measures cognitive, affective and behavioural components of attitudes towards persons with ID. Correlational and multivariate regression analyses were performed. Frequent contacts with persons with ID and experience of including a child with ID increased the likelihood of reporting prior positive contacts with persons with ID. In turn, this was associated with less discomfort towards persons with ID and more willingness towards interactions. In-service training on ID was related to better knowledge of rights and capabilities of persons with ID. Experience of including a child with ID in general education classrooms increased the likelihood to report feeling competent in teaching children with ID, which predicted more willingness to include children with ID.     

商州丧葬方言词及其文化内涵探微

陕西商州的丧葬方言词语真实地记录了农村丧葬习俗的全过程,再现了古朴醇厚的地域文化踪迹。商州农村丧葬礼俗极具地方特色,丧葬习俗中出现的方言俗语数量繁多、内涵丰富。联系商州自然地理状况、历史人文背景,选取有代表意义的方言俗语进行研究,分析此类词语反映的思想内涵,进而揭示商州的地域文化和民众的文化心理。     

职业教育中学生的能力培养研究

当代大学生的能力包括认知能力、操作能力和社交能力三种,我们通过分析教学过程中知识、技能和能力之间的关系,提出了通过知识传授培养学生认知能力和社交能力、通过技能训练培养学生实践操作能力的方法和途径,提高了学生适应各种不同工作岗位的综合素质,增强了学生从容面对新岗位、新问题挑战的自信。     

斜拉桥主梁施工底板局部承压安全验算方法

混凝土斜拉桥采用挂篮施工主梁时,挂篮底部行走轮对主梁底板产生巨大的竖向反力.混凝土底板、肋板可能在此反力作用下发生局部承压开裂破坏,需进行安全验算.行走轮与底板的接触区域是未知的,混凝土的受力变形均由接触区域决定.为寻求简单适用的计算方法,采用弹性接触Hertz理论,求解行走轮与混凝土板接触区域大小及应力分布,在此基础上应用规范推荐公式进行底板及肋板的抗裂安全验算.算例表明,该方法是可行的,可以简便地进行主梁底板的局部承压安全验算.     

在交往中实施英语教学创新

英语教学在师生的交往中进行创新，一是要有师生友好交往，共同活动的观念，在和谐、民主、平等的交往与合作中以教促学，互教互学。二是形成一个尊重、理解、促动学生的过程，用师生的创造性思想和学生自己的发现，充实教学活力。三是建立“多元目标——激情导趣——实践探索——应用创新”的开放教学结构。四是综合运用空间法、感受法、表现——理解法、竞争法、二课堂备课制作法，创新课堂教学形式。     

热仿真软件在电子设备设计应用中的优缺点

热仿真在目前的设计流程中大量使用,本文描述了此类软件相比传统热设计在计算扩散热阻和对流换热系数时的优点,也描述了其无法解决非线性问题和尺度差异问题的缺点。描述的同时提出了几个相关的实例进行了分析阐述。在文章的最后提出了解决这些问题可能的途径,强调了在使用这些软件的同时必须清楚掌握相关物理事实,才能有利于指导设计实践。