计算机测控光的偏振教学实验系统     

朱昊  高永丰  劳维旻  孙利群  谭峭峰  郭宏 《实验室研究与探索》2014,33(10):125-128

针对传统偏振光与波片实验需人工调节偏振片和波片转角并记录数据,过程繁琐、数据量大、耗时过长的问题,开发出计算机测控的教学实验系统。以半导体固体激光器为光源,PC机通过USB接口和控制器驱动步进电机,带动中心有透光孔的精密电控旋转台按设定步距角转动。激光束与转台中心同轴,偏振片或波片同心安装在旋转台上同步旋转,透射光经过检偏器,由数字式光功率计检测通过各元件后光强的变化;信号经另一USB接口传输至PC机。计算机控制偏振片或波片旋转,同时自动采集对应转角的透射光强值并存储。实验结束后检测结果可通过数据文件导出,由学生在课后自行处理。新教学实验系统可完成1/4和1/2波片实验,验证马吕斯定律,能大幅度节省实验时间并提高精度。  相似文献   

工作搜寻偏好、心理资本与工作搜寻绩效的关系研究——基于地方应用型本科高校2013届毕业生的调查     

王勇 《扬州大学学报(高教研究版)》2014,(2):34-40

工作搜寻偏好是指工作搜寻者在面对几个或者多个工作搜寻方式或工作搜寻结果时,选择其中某一个方式或结果的倾向性。以江苏地方应用型本科高校2013届毕业生为对象,探讨工作搜寻偏好对工作搜寻绩效的影响,并分析心理资本在工作搜寻偏好和工作搜寻绩效间的调节作用。结果表明工作搜寻偏好对工作搜寻绩效存在不同程度的影响,心理资本在工作搜寻偏好和工作搜寻绩效间起着部分调节作用。  相似文献   

Overlaps of multiple database retrieval and citation tracking in dementia care research: a methodological study     

Julian Hirt  Johannes Bergmann  Melanie Karrer 《Journal of the Medical Library Association》2021,109(2):275

Objective:We aimed to determine overlaps and optimal combination of multiple database retrieval and citation tracking for evidence synthesis, based on a previously conducted scoping review on facilitators and barriers to implementing nurse-led interventions in dementia care.Methods:In our 2019 scoping review, we performed a comprehensive literature search in eight databases (CENTRAL, CINAHL, Embase, Emcare, MEDLINE, Ovid Nursing Database, PsycINFO, and Web of Science Core Collection) and used citation tracking. We retrospectively analyzed the coverage and overlap of 10,527 retrieved studies published between 2015 and 2019. To analyze database overlap, we used cross tables and multiple correspondence analysis (MCA).Results:Of the retrieved studies, 6,944 were duplicates and 3,583 were unique references. Using our search strategies, considerable overlaps can be found in some databases, such as between MEDLINE and Web of Science Core Collection or between CINAHL, Emcare, and PsycINFO. Searching MEDLINE, CINAHL, and Web of Science Core Collection and using citation tracking were necessary to retrieve all included studies of our scoping review.Conclusions:Our results can contribute to enhancing future search practice related to database selection in dementia care research. However, due to limited generalizability, researchers and librarians should carefully choose databases based on the research question. More research on optimal database retrieval in dementia care research is required for the development of methodological standards.  相似文献   

Who is blocking access to PubMed? Educational ‘Escape Room’ for medical residents     

Noelia lvarez‐Díaz  Eullia Grifol‐Clar 《Health information and libraries journal》2021,38(1):72-76

Teaching students how to conduct bibliographic searches in health sciences’ databases is essential training. One of the challenges librarians face is how to motivate students during classroom learning. In this article, two hospital libraries, in Spain, used Escape rooms as a method of bringing creativity, teamwork, communication and critical thinking into bibliographic search instruction. Escape rooms are a series of puzzles that must be solved to exit the game. This article explores the methods used for integrating escape rooms into training programmes and evaluates the results. Escape Rooms are a useful tool that can be integrated into residents’ training to support their instruction on bibliographic searches. This kind of learning stablishes competences like logical thinking and deductive approaching. These aspects aid participants to make their own decision and to develop social and intellectual skills.  相似文献   

基于Hessian矩阵的多结构光条纹中心快速提取方法     

贾卫平  王邦国 《大连大学学报》2014,(6):34-37

使用结构光方法对物体进行三维检测时,需要对图像中结构光条纹中心快速、准确提取。为提高检测速度,可向待测物体同时投射多结构光条。为实现多结构光条纹识别和亚像素中心快速提取,本文提出一种基于Hessian的多结构光条纹亚像素中心提取方法。该方法首先对多结构光条纹进行识别,根据识别的结构光条纹计算各条纹上的极值点,最后在极值点像素位置附近区域确定结构光条纹的亚像素中心。实验表明,该方法减小了Hessian矩阵算法的运算量,提高了结构光亚像素中心提取速度,能满足多结构光条纹识别和亚像素中心快速提取的需要。  相似文献   

YCbCr色彩空间的彩色图像光线补偿方法研究     

周虹 《柳州职业技术学院学报》2014,(3):50-53

在进行人脸检测过程中,自然光源光照条件和取景设备对图像原本色彩存在干扰影响,这样很难满足人脸识别系统的要求。从图像进行光照补偿处理的方法和效果的研究出发,实验证明:在图像背景相当简单的情况下,采用参考白光线补偿方法可以很好地对色温差图像进行光照补偿处理,消除了光照的影响力,使后续的处理更适合进行人脸识别性能。  相似文献   

A prospective,randomized crossover study comparing direct inspection by light microscopy versus projected images for teaching of hematopathology to medical students          下载免费PDF全文

Aaron M. Carlson  Ellen D. McPhail  Vilmarie Rodriguez  Georgene Schroeder  Alexandra P. Wolanskyj 《Anatomical sciences education》2014,7(2):130-134

Instruction in hematopathology at Mayo Medical School has evolved from instructor‐guided direct inspection under the light microscope (laboratory method), to photomicrographs of glass slides with classroom projection (projection method). These methods have not been compared directly to date. Forty‐one second‐year medical students participated in this pilot study, a prospective, randomized, crossover study measuring educational performance during a hematology pathophysiology course. The students were randomized to one of two groups. All students received the same didactic lectures in the classroom and subsequent case‐based review of peripheral blood smears using either laboratory or projection methods, on day one with a crossover to the other method on day two. Pre‐ and post‐test examinations centered on morphology recognition measured educational performance on each day, followed by a questionnaire identifying the student's favored method. There was no significant difference in the pre‐test and post‐test scores between the two teaching methods (rank‐sum P = 0.43). Students overwhelmingly preferred the projection method and perceived it as superior (76%), although post‐test scores were not significantly different. Student's recommended method was split with 50% favoring the projection method, 43% favoring a combined approach, and 23% noting logistical challenges to the laboratory. In this study, the laboratory and projection method were equivalent in terms of educational performance for hematopathology among medicals students. A classroom‐based approach such as the projection method is favored, given the large class sizes in undergraduate medical education, as well as the ergonomic challenges and additional resources required for large group instruction in a laboratory setting. Anat Sci Educ 7: 130–134. © 2013 American Association of Anatomists.  相似文献   

基于Hysys的LNG轻烃分离流程模拟及参数优化     

何友祥  王晓丹  聂子豪  张永虎  王聚才 《兰州石化职业技术学院学报》2014,(3):1-3

为了充分利用进口LNG中所潜藏的巨大资源——冷能及C2+轻烃,以流程软件Hysys为工具,按照冷能梯级利用原理,设计了一种LNG轻烃分离流程;并以我国典型进口LNG组分为例,通过模拟计算和优化,乙烷及LPG回收率均在95%左右,而系统能耗仅为1.8MW。  相似文献   

彭学明《娘》文学现象三论     

杨华丽 《绵阳师范学院学报》2014,(1):51-55

土家族作家彭学明的长篇纪实散文《娘》引发了不同层次、不同领域、不同性别人群的阅读、传播和言说兴趣,其热销和持续发酵,反映了我们这个时代的某些精神症候。首先,《娘》个人性与普世性相融汇的特质,使得它成了不同读者观照历史、政治以及自身家庭伦理关系的一面镜子,也是照亮与作家有着不同生存经历的读者走近历史、探究真相的一盏灯;其次,《娘》提出了如何爱、如何孝顺,以及如何重建家庭伦理的社会问题;此外,《娘》反映了"我"接受现代意识的规训这一深层原因,"我"努力寻求他者认同、终于失效以至返回娘代表的传统意识的过程,是现代社会中我们的共同境遇。故而,《娘》成为一种文学现象,是一种必然。  相似文献   

A passion for portraits: Elizabeth Cay's pastels     

Thea Burns  Ashok Roy 《文物保护研究》2014,59(5):279-288

Elizabeth Cay (1771–1831), the grandmother of the Scottish physicist James Clerk Maxwell (1831–1879), was a talented amateur pastellist; several of her pastel portraits survive as does her set of pastels. She studied with Archibald Skirving (1749–1819), a Scottish miniature painter who later in life turned to larger-scale portraiture in pastel and served as drawing master to the Edinburgh elite. Cay's pastels are not fabricated sticks but consist of powdered pigment housed in various glass and ceramic containers and were apparently applied by stumps, still in her workbox, or brushes. The Cay color samples were identified by spectrographic analysis, polarized light microscopy, and microchemical tests which, in addition, indicated that a number of pigment mixtures present gave specific hues in keeping with earlier treatise accounts of the preparation of a pastel gamut for practical use. Elizabeth Cay's pastel workbox may be rare surviving evidence of one way, more common that we appreciate today, in which amateurs, and perhaps professionals, practiced pastel painting.  相似文献