Boundary control of a linear distributed parameter bioprocess

This paper is concerned with boundary control of a linear distributed parameter bioprocess. Huang's result (Ann. Differential Equations 1(1) (1985) 43) on the spectrum determined growth assumption is applied to prove that the closed-loop system becomes exponentially stable under a certain condition with respect to the feedback gain. Moreover, it is shown that the decay rate of the open-loop system is given by letting the feedback gain tend to zero.     

利用全息技术构建图书馆数字资源新的存储平台

存储技术和存储设备的建设是构造现代化数字图书馆的基础组成部分。全息存储是一种利用激光干涉原理将图文等信息记录在感光介质上的大容量信息存储技术，它可以在不改变激光波长的情况下，极大的提高存储密度。随着仝息存储技术和相关标准的不断发展和完善，这种存储解决方案将会给图书馆存储基础设施的建设带来极大的益处。     

Optimization of some factors affecting the performance of query expansion

This paper examines the factors affecting the performance of global query expansion based on term co-occurrence data and suggests a way to maximize the retrieval effectiveness. Major parameters to be optimized through experiments are term similarity measure and the weighting scheme of additional terms. The evaluation of four similarity measures tested in query expansion reveal that mutual information and Yule's Y, which emphasize low frequency terms, achieve better performance than cosine and Jaccard coefficients that have the reverse tendency. In the evaluation of three weighting schemes, similarity weight performs well only with short queries, whereas fixed weights of approximately 0.5 and similarity rank weights were effective with queries of any length. Furthermore, the optimal similarity rank weight achieving the best overall performance seems to be the least affected by test collections and the number of additional terms. For the efficiency of retrieval, the number of additional terms needs not exceed 70 in our test collections, but the optimal number may vary according to the characteristics of the similarity measure employed.     

在基因-脑-行为的框架下探索果蝇面对竞争的视觉线索的抉择行为

2001年11月16日出版的Science [1] 发表了唐世明和郭爱克的“果蝇面对竞争的视觉线索的抉择行为”的研究论文,在相关领域引起了广泛兴趣,已陆续被国际权威学者引用。主要介绍了其研究内容、研究方法及所取得的进展,并简单介绍了论文发表后国际上的引用情况以及新的进展。     

组织即兴、组织学习和组织记忆三者关系的研究

在回顾组织即兴、组织记忆和组织学习相关文献的基础上,指出现有文献只是研究了组织即兴与组织记忆,组织即兴与组织学习的两两关系,没能进一步探究组织即兴、组织学习和组织记忆三者之间的关系。因此,提出了组织即兴与组织学习和组织记忆三者之间的动态关系模型。     

Prostate specific antigen in patients of benign prostate hypertrophy and carcinoma prostate

Prostate Specific Antigen (PSA) has emerged as the most applicable and important tumor marker for carcinoma prostate. In the present study PSA was determined in serum of healthy subjects, patients of benign prostate hypertrophy (BPH) and Carcinoma Prostate (Ca−P) to evaluate its diagnostic efficiency in day to day management of prostate cancer patients and in differentiating patients of early prostate cancer from those with BPH. Receiver operating characteristic curve (ROC) revealed 2 ng/ml and 10 ng/ml cut off serum PSA level for BPH and untreated carcinoma prostate patients (Ca−P). An extremely significant increase (P<0.0001) was observed in mean PSA concentration in BPH patients and adenocarcinoma prostate patients when compared to healthy males. Clinical relevance of PSA was highlighted by a case study of cancer patient prior to any therapy till death.     

新时期档案机构参与非遗保护的反思与再定位

21世纪以来,在社会参与非遗保护的热潮中,档案学界对档案机构的参与寄予厚望,但本文通过文献调查发现,实践中档案机构的参与状况并不理想,呈现小规模和自发性的参与特点;参与方式虽体现出专业化优势,但存在较大的局限性;参与效果呈现边缘化和形式化窘境。作者认为缺乏动力、缺乏魄力、缺乏实力是造成档案机构参与状况不理想的主要原因。最后,文章提出在新时期档案机构应重新定位参与非遗保护的角色,把握文化治理趋势彰显档案馆的人文关怀,抓住记忆建构趋势开展非遗档案资源库建设,紧追人文研究趋势拓展非遗数字人文服务,重视文化服务趋势参与非遗专题资源整合共享,关注文化传播趋势加强非遗文化知识传播,正视文化传承趋势开展非遗档案知识服务。     

我国档案社会记忆研究的文献计量及可视化分析

对档案学核心期刊中244篇档案社会记忆研究论文进行文献计量及双聚类分析,可以直观、科学地反映我国档案社会记忆研究的发展状况。我国档案社会记忆研究目前已趋于成熟发展阶段,研究主体呈现出多元化趋势,研究主题主要集中在后保管时代档案社会记忆价值构建、档案记忆和权力与身份认同的关系、非物质文化遗产及边缘弱势群体的档案记忆、数字档案记忆资源的整合和开发等方面。建议在档案社会记忆范式构建期继续深化理论研究深度,将档案社会记忆的学理性与应用性相结合,发挥理论研究的现实指导和发展预测功能。     

Component skills of text comprehension in less competent Chinese comprehenders

The present study examined the role of verbal working memory (memory span and tongue-twister), two-character Chinese pseudoword reading (two tasks), rapid automatized naming (RAN) (letters and numbers), and phonological segmentation (deletion of rimes and onsets) in inferential text comprehension in Chinese in 31 less competent comprehenders compared with 37 reading comprehension control students and 23 chronological age controls. It was hypothesized that the target students would perform poorly on these cognitive and linguistic tasks as compared with their controls. Furthermore, verbal working memory and pseudoword reading would explain a considerable amount of individual variation in Chinese text comprehension. RAN would have a nonsignificant role in text comprehension. Structural equation analyses and hierarchical multiple regression analyses generally upheld these hypotheses. Our findings support current literature of the role of verbal working memory in reading comprehension found in English. The results, however, suggest differential role of the constructs and the tasks in reading comprehension and provide some answers for comprehension impairment in Chinese students.     

Phonological processing and emergent literacy in younger and older preschool children

Phonological awareness, phonological memory, and phonological access to lexical storage play important roles in acquiring literacy. We examined the convergent, discriminant, and predictive validity of these phonological processing abilities (PPA) in 389 3-, 4-, and 5-year-old children. Confirmatory factor analysis supported the validity of each PPA as separate from general cognitive ability and separate from each other. Multigroup structural equation modeling (SEM) with mean structure demonstrated that older preschoolers have better developed latent PPA than younger preschoolers but that the structure of PPA is equivalent. RAN was found uniquely associated with letter knowledge and text discrimination in younger preschoolers, and PA was found uniquely associated with word reading skills in older preschoolers. Finally, general cognitive ability was only indirectly associated with emergent literacy via PPA. These results highlight the importance of PPA in the early literacy development of English-speaking preschool children.