基于齿轮形修磨轮的蜗杆与齿轮传动齿面接触分析

基于齿轮形金钢面修磨轮 ,TI蜗杆才能被精修磨 ,由此形成一种 TI蜗杆与渐开线斜齿轮的啮合传动型式 .本文对于这种新型传动副 ,建立了数学模型 ,推导出了若干基本方程式 ,并且进行了齿面接触分析 .理论分析表明这种蜗杆传动具有许多优点 .     

AMC视角下多市场接触对企业研发强度的影响--基于全球医药行业的实证研究

以往对多市场接触的研究大多集中于考察多市场接触对下游产品市场竞争强度的影响，本文将研究的注意力转向上游要素市场。基于多市场接触理论和动态竞争的意识—动机—能力 (awareness-motivation-capability, AMC) 框架，探讨了多市场接触对企业研发强度的影响。对全球最大的38家制药企业2007—2016年期间的面板数据分析表明，把企业间竞争的范围延伸到上游研发市场时，多市场接触会表现出显著的竞争效应，即多市场接触会正向影响企业的研发强度，从而说明经典的相互克制效应并不适用于要素市场。此外，本文检验了多市场接触和研发强度关系的边界条件，焦点企业专利存量和现金持有比会削弱多市场接触和研发强度之间的正向关系，而销量下降产品比例会强化二者之间关系。     

Gardnerella vaginalis infection and sexual contact in female children

Gardnerella vaginalis (GV) infection has been reported as being acquired via sexual contact in adults and as an indicator of sexual contact in female children (DeJong, 1985). The purpose of this study was to determine if GV infection was more commonly found in 191 female children who gave a history of sexual contact and/or were infected with Neisseria gonorrhoeae (GC) or Chlamydia trachomatis (CT) (Group 1), compared with 144 female children evaluated for possible sexual abuse and found to have no such history or infection with GC or CT (Group 2), or 31 female children (friends of the authors) without such a history or GC or CT infection (Group 3). Vaginal GV was found in 5.3% of Group 1, 4.9% of Group 2 and 6.4% of Group 3 (p > .05). Also, vaginal GV infection was not related to the type of sexual contact or race, but did increase with age in white female children. Because vaginal GV infection is not more commonly found in children with a history of sexual contact than those without such a history, the finding of GV in a vaginal culture in an individual case would not be a reliable marker of sexual contact. Routine culturing for GV is not recommended as part of a sexual abuse workup.     

Young adults’ contact experiences and attitudes toward aging: age salience and intergroup anxiety in South Korea*

From the theoretical perspectives of communication accommodation and intergroup contact, this study examined South Korean young adults’ (N?=?301) perceptions of their communication experiences with a frequently-contacted grandparent, as well as attitudes toward older adults and own aging. Findings from structural equation modeling indicated that the participants’ attitudes towards older adults were positively predicted by contact frequency with the grandparent and negatively predicted by perceptions of the grandparent’s non-accommodative communication. Analyses of indirect effects revealed that young adults’ intergroup anxiety explained these associations. Although the direct effects of contact frequency and the grandparent’s non-accommodation on attitudes toward own aging were nonsignificant, the indirect effects through intergroup anxiety were significant. Moderation analysis indicated that these direct and indirect associations between non-accommodation and aging attitudes were significant only when age salience was low – a finding contrary to existing theory and research. Results are discussed in terms of intergenerational communication and culture, and theories of intergroup contact.     

Exploring the de-stigmatizing effect of social media on homosexuality in China: an interpersonal-mediated contact versus parasocial-mediated contact perspective

The subject of homosexuality remains taboo in contemporary China, given that the public maintains a considerably negative attitude toward the subject. Recent Pew Research indicates that, on average, 21% of Chinese respondents believe that homosexuality should be accepted. However, parallel surveys of Internet users paint a different picture, as online surveys found a more liberal atmosphere toward homosexuality and same-sex marriage. The online and offline discrepancy in attitudes toward homosexuality begs the question of whether the Internet carries a stigma-reducing function in terms of views on sexual minority groups. Guided by the contact hypothesis and parasocial contact theory, the current study investigates the de-stigmatizing effect of the social media on homosexuality in China. A web-based survey with 980 social media users with a heterosexual orientation confirmed the positive role of interpersonal-mediated contact with lesbian and gay celebrities via social media venues in stigma reduction; but findings did not lend support to the parasocial-mediated contact hypothesis.     

Study on properties of residue-residue contacts in protein

INTRODUCTION Recognition of protein folding from aminoacid sequence is a challenging task. The structureand stability of proteins from different fold aremainly dictated by inter-residue interactions. In-formation on the distribution of contacts shown by20 amino acid residues can be used to predict thefolding type of each protein (Chan and Dill, 1998;Zhang and Kim, 2000; Gromiha, 2001; Gromihaand Selvaraj, 1999; Miyazawa and Jernigan, 1985;1996; Bahar et al., 1997; McDonald and …     

西宁方言中SOV句式浅析

本文简要论述了西宁方言中SOV句式，着重从历史、文化、语言本身的特质等方面进行论述，认为西宁方言是汉语与其他民族语言交融的结果。     

略论网络用语中的语词接触现象

网络的迅猛发展,为网络用语的产生提供了条件。由于现代汉语与外界接触时存在着语词缺项等原因,网络用语中出现了大量的语词接触现象。网络空间已经形成了一个不同于现实空间的言语社区,出现了语码转换、语码混杂、语词借用和语言干扰等现象。这种语词接触现象是由于语词结构缺项等原因而产生的。     

核桃苗地金龟子防治试验初报

经过我们连续两年的大田及室内试验,结果表明,对金龟子幼虫(蛴螬)的防治应以触杀为主,合理的土壤化学药剂处理均能收到很好的防治效果.